fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card ([email protected])
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller ([email protected]), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/uaccess.h>
  43 #include <linux/iversion.h>
  44 #include <linux/unicode.h>
  45 #include <linux/part_stat.h>
  46 #include <linux/kthread.h>
  47 #include <linux/freezer.h>
  48 #include <linux/fsnotify.h>
  49 #include <linux/fs_context.h>
  50 #include <linux/fs_parser.h>
  51
  52 #include "ext4.h"
  53 #include "ext4_extents.h"       /* Needed for trace points definition */
  54 #include "ext4_jbd2.h"
  55 #include "xattr.h"
  56 #include "acl.h"
  57 #include "mballoc.h"
  58 #include "fsmap.h"
  59
  60 #define CREATE_TRACE_POINTS
  61 #include <trace/events/ext4.h>
  62
  63 static struct ext4_lazy_init *ext4_li_info;
  64 static DEFINE_MUTEX(ext4_li_mtx);
  65 static struct ratelimit_state ext4_mount_msg_ratelimit;
  66
  67 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  68                              unsigned long journal_devnum);
  69 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  70 static void ext4_update_super(struct super_block *sb);
  71 static int ext4_commit_super(struct super_block *sb);
  72 static int ext4_mark_recovery_complete(struct super_block *sb,
  73                                         struct ext4_super_block *es);
  74 static int ext4_clear_journal_err(struct super_block *sb,
  75                                   struct ext4_super_block *es);
  76 static int ext4_sync_fs(struct super_block *sb, int wait);
  77 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  78 static int ext4_unfreeze(struct super_block *sb);
  79 static int ext4_freeze(struct super_block *sb);
  80 static inline int ext2_feature_set_ok(struct super_block *sb);
  81 static inline int ext3_feature_set_ok(struct super_block *sb);
  82 static void ext4_destroy_lazyinit_thread(void);
  83 static void ext4_unregister_li_request(struct super_block *sb);
  84 static void ext4_clear_request_list(void);
  85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  86                                             unsigned int journal_inum);
  87 static int ext4_validate_options(struct fs_context *fc);
  88 static int ext4_check_opt_consistency(struct fs_context *fc,
  89                                       struct super_block *sb);
  90 static int ext4_apply_options(struct fs_context *fc, struct super_block *sb);
  91 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param);
  92 static int ext4_get_tree(struct fs_context *fc);
  93 static int ext4_reconfigure(struct fs_context *fc);
  94 static void ext4_fc_free(struct fs_context *fc);
  95 static int ext4_init_fs_context(struct fs_context *fc);
  96 static const struct fs_parameter_spec ext4_param_specs[];
  97
  98 /*
  99  * Lock ordering
 100  *
 101  * page fault path:
 102  * mmap_lock -> sb_start_pagefault -> invalidate_lock (r) -> transaction start
 103  *   -> page lock -> i_data_sem (rw)
 104  *
 105  * buffered write path:
 106  * sb_start_write -> i_mutex -> mmap_lock
 107  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 108  *   i_data_sem (rw)
 109  *
 110  * truncate:
 111  * sb_start_write -> i_mutex -> invalidate_lock (w) -> i_mmap_rwsem (w) ->
 112  *   page lock
 113  * sb_start_write -> i_mutex -> invalidate_lock (w) -> transaction start ->
 114  *   i_data_sem (rw)
 115  *
 116  * direct IO:
 117  * sb_start_write -> i_mutex -> mmap_lock
 118  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 119  *
 120  * writepages:
 121  * transaction start -> page lock(s) -> i_data_sem (rw)
 122  */
 123
 124 static const struct fs_context_operations ext4_context_ops = {
 125         .parse_param    = ext4_parse_param,
 126         .get_tree       = ext4_get_tree,
 127         .reconfigure    = ext4_reconfigure,
 128         .free           = ext4_fc_free,
 129 };
 130
 131
 132 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 133 static struct file_system_type ext2_fs_type = {
 134         .owner                  = THIS_MODULE,
 135         .name                   = "ext2",
 136         .init_fs_context        = ext4_init_fs_context,
 137         .parameters             = ext4_param_specs,
 138         .kill_sb                = kill_block_super,
 139         .fs_flags               = FS_REQUIRES_DEV,
 140 };
 141 MODULE_ALIAS_FS("ext2");
 142 MODULE_ALIAS("ext2");
 143 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 144 #else
 145 #define IS_EXT2_SB(sb) (0)
 146 #endif
 147
 148
 149 static struct file_system_type ext3_fs_type = {
 150         .owner                  = THIS_MODULE,
 151         .name                   = "ext3",
 152         .init_fs_context        = ext4_init_fs_context,
 153         .parameters             = ext4_param_specs,
 154         .kill_sb                = kill_block_super,
 155         .fs_flags               = FS_REQUIRES_DEV,
 156 };
 157 MODULE_ALIAS_FS("ext3");
 158 MODULE_ALIAS("ext3");
 159 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 160
 161
 162 static inline void __ext4_read_bh(struct buffer_head *bh, int op_flags,
 163                                   bh_end_io_t *end_io)
 164 {
 165         /*
 166          * buffer's verified bit is no longer valid after reading from
 167          * disk again due to write out error, clear it to make sure we
 168          * recheck the buffer contents.
 169          */
 170         clear_buffer_verified(bh);
 171
 172         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
 173         get_bh(bh);
 174         submit_bh(REQ_OP_READ, op_flags, bh);
 175 }
 176
 177 void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
 178                          bh_end_io_t *end_io)
 179 {
 180         BUG_ON(!buffer_locked(bh));
 181
 182         if (ext4_buffer_uptodate(bh)) {
 183                 unlock_buffer(bh);
 184                 return;
 185         }
 186         __ext4_read_bh(bh, op_flags, end_io);
 187 }
 188
 189 int ext4_read_bh(struct buffer_head *bh, int op_flags, bh_end_io_t *end_io)
 190 {
 191         BUG_ON(!buffer_locked(bh));
 192
 193         if (ext4_buffer_uptodate(bh)) {
 194                 unlock_buffer(bh);
 195                 return 0;
 196         }
 197
 198         __ext4_read_bh(bh, op_flags, end_io);
 199
 200         wait_on_buffer(bh);
 201         if (buffer_uptodate(bh))
 202                 return 0;
 203         return -EIO;
 204 }
 205
 206 int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait)
 207 {
 208         if (trylock_buffer(bh)) {
 209                 if (wait)
 210                         return ext4_read_bh(bh, op_flags, NULL);
 211                 ext4_read_bh_nowait(bh, op_flags, NULL);
 212                 return 0;
 213         }
 214         if (wait) {
 215                 wait_on_buffer(bh);
 216                 if (buffer_uptodate(bh))
 217                         return 0;
 218                 return -EIO;
 219         }
 220         return 0;
 221 }
 222
 223 /*
 224  * This works like __bread_gfp() except it uses ERR_PTR for error
 225  * returns.  Currently with sb_bread it's impossible to distinguish
 226  * between ENOMEM and EIO situations (since both result in a NULL
 227  * return.
 228  */
 229 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 230                                                sector_t block, int op_flags,
 231                                                gfp_t gfp)
 232 {
 233         struct buffer_head *bh;
 234         int ret;
 235
 236         bh = sb_getblk_gfp(sb, block, gfp);
 237         if (bh == NULL)
 238                 return ERR_PTR(-ENOMEM);
 239         if (ext4_buffer_uptodate(bh))
 240                 return bh;
 241
 242         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
 243         if (ret) {
 244                 put_bh(bh);
 245                 return ERR_PTR(ret);
 246         }
 247         return bh;
 248 }
 249
 250 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 251                                    int op_flags)
 252 {
 253         return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
 254 }
 255
 256 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 257                                             sector_t block)
 258 {
 259         return __ext4_sb_bread_gfp(sb, block, 0, 0);
 260 }
 261
 262 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
 263 {
 264         struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
 265
 266         if (likely(bh)) {
 267                 ext4_read_bh_lock(bh, REQ_RAHEAD, false);
 268                 brelse(bh);
 269         }
 270 }
 271
 272 static int ext4_verify_csum_type(struct super_block *sb,
 273                                  struct ext4_super_block *es)
 274 {
 275         if (!ext4_has_feature_metadata_csum(sb))
 276                 return 1;
 277
 278         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 279 }
 280
 281 __le32 ext4_superblock_csum(struct super_block *sb,
 282                             struct ext4_super_block *es)
 283 {
 284         struct ext4_sb_info *sbi = EXT4_SB(sb);
 285         int offset = offsetof(struct ext4_super_block, s_checksum);
 286         __u32 csum;
 287
 288         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 289
 290         return cpu_to_le32(csum);
 291 }
 292
 293 static int ext4_superblock_csum_verify(struct super_block *sb,
 294                                        struct ext4_super_block *es)
 295 {
 296         if (!ext4_has_metadata_csum(sb))
 297                 return 1;
 298
 299         return es->s_checksum == ext4_superblock_csum(sb, es);
 300 }
 301
 302 void ext4_superblock_csum_set(struct super_block *sb)
 303 {
 304         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 305
 306         if (!ext4_has_metadata_csum(sb))
 307                 return;
 308
 309         es->s_checksum = ext4_superblock_csum(sb, es);
 310 }
 311
 312 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 313                                struct ext4_group_desc *bg)
 314 {
 315         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 316                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 317                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 318 }
 319
 320 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 321                                struct ext4_group_desc *bg)
 322 {
 323         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 324                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 325                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 326 }
 327
 328 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 329                               struct ext4_group_desc *bg)
 330 {
 331         return le32_to_cpu(bg->bg_inode_table_lo) |
 332                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 333                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 334 }
 335
 336 __u32 ext4_free_group_clusters(struct super_block *sb,
 337                                struct ext4_group_desc *bg)
 338 {
 339         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 340                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 341                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 342 }
 343
 344 __u32 ext4_free_inodes_count(struct super_block *sb,
 345                               struct ext4_group_desc *bg)
 346 {
 347         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 348                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 349                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 350 }
 351
 352 __u32 ext4_used_dirs_count(struct super_block *sb,
 353                               struct ext4_group_desc *bg)
 354 {
 355         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 356                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 357                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 358 }
 359
 360 __u32 ext4_itable_unused_count(struct super_block *sb,
 361                               struct ext4_group_desc *bg)
 362 {
 363         return le16_to_cpu(bg->bg_itable_unused_lo) |
 364                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 365                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 366 }
 367
 368 void ext4_block_bitmap_set(struct super_block *sb,
 369                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 370 {
 371         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 372         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 373                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 374 }
 375
 376 void ext4_inode_bitmap_set(struct super_block *sb,
 377                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 378 {
 379         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 380         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 381                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 382 }
 383
 384 void ext4_inode_table_set(struct super_block *sb,
 385                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 386 {
 387         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 388         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 389                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 390 }
 391
 392 void ext4_free_group_clusters_set(struct super_block *sb,
 393                                   struct ext4_group_desc *bg, __u32 count)
 394 {
 395         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 396         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 397                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 398 }
 399
 400 void ext4_free_inodes_set(struct super_block *sb,
 401                           struct ext4_group_desc *bg, __u32 count)
 402 {
 403         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 404         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 405                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 406 }
 407
 408 void ext4_used_dirs_set(struct super_block *sb,
 409                           struct ext4_group_desc *bg, __u32 count)
 410 {
 411         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 412         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 413                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 414 }
 415
 416 void ext4_itable_unused_set(struct super_block *sb,
 417                           struct ext4_group_desc *bg, __u32 count)
 418 {
 419         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 420         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 421                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 422 }
 423
 424 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi, time64_t now)
 425 {
 426         now = clamp_val(now, 0, (1ull << 40) - 1);
 427
 428         *lo = cpu_to_le32(lower_32_bits(now));
 429         *hi = upper_32_bits(now);
 430 }
 431
 432 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 433 {
 434         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 435 }
 436 #define ext4_update_tstamp(es, tstamp) \
 437         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi, \
 438                              ktime_get_real_seconds())
 439 #define ext4_get_tstamp(es, tstamp) \
 440         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 441
 442 /*
 443  * The del_gendisk() function uninitializes the disk-specific data
 444  * structures, including the bdi structure, without telling anyone
 445  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 446  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 447  * This is a kludge to prevent these oops until we can put in a proper
 448  * hook in del_gendisk() to inform the VFS and file system layers.
 449  */
 450 static int block_device_ejected(struct super_block *sb)
 451 {
 452         struct inode *bd_inode = sb->s_bdev->bd_inode;
 453         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 454
 455         return bdi->dev == NULL;
 456 }
 457
 458 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 459 {
 460         struct super_block              *sb = journal->j_private;
 461         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 462         int                             error = is_journal_aborted(journal);
 463         struct ext4_journal_cb_entry    *jce;
 464
 465         BUG_ON(txn->t_state == T_FINISHED);
 466
 467         ext4_process_freed_data(sb, txn->t_tid);
 468
 469         spin_lock(&sbi->s_md_lock);
 470         while (!list_empty(&txn->t_private_list)) {
 471                 jce = list_entry(txn->t_private_list.next,
 472                                  struct ext4_journal_cb_entry, jce_list);
 473                 list_del_init(&jce->jce_list);
 474                 spin_unlock(&sbi->s_md_lock);
 475                 jce->jce_func(sb, jce, error);
 476                 spin_lock(&sbi->s_md_lock);
 477         }
 478         spin_unlock(&sbi->s_md_lock);
 479 }
 480
 481 /*
 482  * This writepage callback for write_cache_pages()
 483  * takes care of a few cases after page cleaning.
 484  *
 485  * write_cache_pages() already checks for dirty pages
 486  * and calls clear_page_dirty_for_io(), which we want,
 487  * to write protect the pages.
 488  *
 489  * However, we may have to redirty a page (see below.)
 490  */
 491 static int ext4_journalled_writepage_callback(struct page *page,
 492                                               struct writeback_control *wbc,
 493                                               void *data)
 494 {
 495         transaction_t *transaction = (transaction_t *) data;
 496         struct buffer_head *bh, *head;
 497         struct journal_head *jh;
 498
 499         bh = head = page_buffers(page);
 500         do {
 501                 /*
 502                  * We have to redirty a page in these cases:
 503                  * 1) If buffer is dirty, it means the page was dirty because it
 504                  * contains a buffer that needs checkpointing. So the dirty bit
 505                  * needs to be preserved so that checkpointing writes the buffer
 506                  * properly.
 507                  * 2) If buffer is not part of the committing transaction
 508                  * (we may have just accidentally come across this buffer because
 509                  * inode range tracking is not exact) or if the currently running
 510                  * transaction already contains this buffer as well, dirty bit
 511                  * needs to be preserved so that the buffer gets writeprotected
 512                  * properly on running transaction's commit.
 513                  */
 514                 jh = bh2jh(bh);
 515                 if (buffer_dirty(bh) ||
 516                     (jh && (jh->b_transaction != transaction ||
 517                             jh->b_next_transaction))) {
 518                         redirty_page_for_writepage(wbc, page);
 519                         goto out;
 520                 }
 521         } while ((bh = bh->b_this_page) != head);
 522
 523 out:
 524         return AOP_WRITEPAGE_ACTIVATE;
 525 }
 526
 527 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
 528 {
 529         struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
 530         struct writeback_control wbc = {
 531                 .sync_mode =  WB_SYNC_ALL,
 532                 .nr_to_write = LONG_MAX,
 533                 .range_start = jinode->i_dirty_start,
 534                 .range_end = jinode->i_dirty_end,
 535         };
 536
 537         return write_cache_pages(mapping, &wbc,
 538                                  ext4_journalled_writepage_callback,
 539                                  jinode->i_transaction);
 540 }
 541
 542 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
 543 {
 544         int ret;
 545
 546         if (ext4_should_journal_data(jinode->i_vfs_inode))
 547                 ret = ext4_journalled_submit_inode_data_buffers(jinode);
 548         else
 549                 ret = jbd2_journal_submit_inode_data_buffers(jinode);
 550
 551         return ret;
 552 }
 553
 554 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
 555 {
 556         int ret = 0;
 557
 558         if (!ext4_should_journal_data(jinode->i_vfs_inode))
 559                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
 560
 561         return ret;
 562 }
 563
 564 static bool system_going_down(void)
 565 {
 566         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 567                 || system_state == SYSTEM_RESTART;
 568 }
 569
 570 struct ext4_err_translation {
 571         int code;
 572         int errno;
 573 };
 574
 575 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
 576
 577 static struct ext4_err_translation err_translation[] = {
 578         EXT4_ERR_TRANSLATE(EIO),
 579         EXT4_ERR_TRANSLATE(ENOMEM),
 580         EXT4_ERR_TRANSLATE(EFSBADCRC),
 581         EXT4_ERR_TRANSLATE(EFSCORRUPTED),
 582         EXT4_ERR_TRANSLATE(ENOSPC),
 583         EXT4_ERR_TRANSLATE(ENOKEY),
 584         EXT4_ERR_TRANSLATE(EROFS),
 585         EXT4_ERR_TRANSLATE(EFBIG),
 586         EXT4_ERR_TRANSLATE(EEXIST),
 587         EXT4_ERR_TRANSLATE(ERANGE),
 588         EXT4_ERR_TRANSLATE(EOVERFLOW),
 589         EXT4_ERR_TRANSLATE(EBUSY),
 590         EXT4_ERR_TRANSLATE(ENOTDIR),
 591         EXT4_ERR_TRANSLATE(ENOTEMPTY),
 592         EXT4_ERR_TRANSLATE(ESHUTDOWN),
 593         EXT4_ERR_TRANSLATE(EFAULT),
 594 };
 595
 596 static int ext4_errno_to_code(int errno)
 597 {
 598         int i;
 599
 600         for (i = 0; i < ARRAY_SIZE(err_translation); i++)
 601                 if (err_translation[i].errno == errno)
 602                         return err_translation[i].code;
 603         return EXT4_ERR_UNKNOWN;
 604 }
 605
 606 static void save_error_info(struct super_block *sb, int error,
 607                             __u32 ino, __u64 block,
 608                             const char *func, unsigned int line)
 609 {
 610         struct ext4_sb_info *sbi = EXT4_SB(sb);
 611
 612         /* We default to EFSCORRUPTED error... */
 613         if (error == 0)
 614                 error = EFSCORRUPTED;
 615
 616         spin_lock(&sbi->s_error_lock);
 617         sbi->s_add_error_count++;
 618         sbi->s_last_error_code = error;
 619         sbi->s_last_error_line = line;
 620         sbi->s_last_error_ino = ino;
 621         sbi->s_last_error_block = block;
 622         sbi->s_last_error_func = func;
 623         sbi->s_last_error_time = ktime_get_real_seconds();
 624         if (!sbi->s_first_error_time) {
 625                 sbi->s_first_error_code = error;
 626                 sbi->s_first_error_line = line;
 627                 sbi->s_first_error_ino = ino;
 628                 sbi->s_first_error_block = block;
 629                 sbi->s_first_error_func = func;
 630                 sbi->s_first_error_time = sbi->s_last_error_time;
 631         }
 632         spin_unlock(&sbi->s_error_lock);
 633 }
 634
 635 /* Deal with the reporting of failure conditions on a filesystem such as
 636  * inconsistencies detected or read IO failures.
 637  *
 638  * On ext2, we can store the error state of the filesystem in the
 639  * superblock.  That is not possible on ext4, because we may have other
 640  * write ordering constraints on the superblock which prevent us from
 641  * writing it out straight away; and given that the journal is about to
 642  * be aborted, we can't rely on the current, or future, transactions to
 643  * write out the superblock safely.
 644  *
 645  * We'll just use the jbd2_journal_abort() error code to record an error in
 646  * the journal instead.  On recovery, the journal will complain about
 647  * that error until we've noted it down and cleared it.
 648  *
 649  * If force_ro is set, we unconditionally force the filesystem into an
 650  * ABORT|READONLY state, unless the error response on the fs has been set to
 651  * panic in which case we take the easy way out and panic immediately. This is
 652  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
 653  * at a critical moment in log management.
 654  */
 655 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
 656                               __u32 ino, __u64 block,
 657                               const char *func, unsigned int line)
 658 {
 659         journal_t *journal = EXT4_SB(sb)->s_journal;
 660         bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
 661
 662         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 663         if (test_opt(sb, WARN_ON_ERROR))
 664                 WARN_ON_ONCE(1);
 665
 666         if (!continue_fs && !sb_rdonly(sb)) {
 667                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
 668                 if (journal)
 669                         jbd2_journal_abort(journal, -EIO);
 670         }
 671
 672         if (!bdev_read_only(sb->s_bdev)) {
 673                 save_error_info(sb, error, ino, block, func, line);
 674                 /*
 675                  * In case the fs should keep running, we need to writeout
 676                  * superblock through the journal. Due to lock ordering
 677                  * constraints, it may not be safe to do it right here so we
 678                  * defer superblock flushing to a workqueue.
 679                  */
 680                 if (continue_fs && journal)
 681                         schedule_work(&EXT4_SB(sb)->s_error_work);
 682                 else
 683                         ext4_commit_super(sb);
 684         }
 685
 686         /*
 687          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 688          * could panic during 'reboot -f' as the underlying device got already
 689          * disabled.
 690          */
 691         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 692                 panic("EXT4-fs (device %s): panic forced after error\n",
 693                         sb->s_id);
 694         }
 695
 696         if (sb_rdonly(sb) || continue_fs)
 697                 return;
 698
 699         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 700         /*
 701          * Make sure updated value of ->s_mount_flags will be visible before
 702          * ->s_flags update
 703          */
 704         smp_wmb();
 705         sb->s_flags |= SB_RDONLY;
 706 }
 707
 708 static void flush_stashed_error_work(struct work_struct *work)
 709 {
 710         struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
 711                                                 s_error_work);
 712         journal_t *journal = sbi->s_journal;
 713         handle_t *handle;
 714
 715         /*
 716          * If the journal is still running, we have to write out superblock
 717          * through the journal to avoid collisions of other journalled sb
 718          * updates.
 719          *
 720          * We use directly jbd2 functions here to avoid recursing back into
 721          * ext4 error handling code during handling of previous errors.
 722          */
 723         if (!sb_rdonly(sbi->s_sb) && journal) {
 724                 struct buffer_head *sbh = sbi->s_sbh;
 725                 handle = jbd2_journal_start(journal, 1);
 726                 if (IS_ERR(handle))
 727                         goto write_directly;
 728                 if (jbd2_journal_get_write_access(handle, sbh)) {
 729                         jbd2_journal_stop(handle);
 730                         goto write_directly;
 731                 }
 732                 ext4_update_super(sbi->s_sb);
 733                 if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
 734                         ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
 735                                  "superblock detected");
 736                         clear_buffer_write_io_error(sbh);
 737                         set_buffer_uptodate(sbh);
 738                 }
 739
 740                 if (jbd2_journal_dirty_metadata(handle, sbh)) {
 741                         jbd2_journal_stop(handle);
 742                         goto write_directly;
 743                 }
 744                 jbd2_journal_stop(handle);
 745                 ext4_notify_error_sysfs(sbi);
 746                 return;
 747         }
 748 write_directly:
 749         /*
 750          * Write through journal failed. Write sb directly to get error info
 751          * out and hope for the best.
 752          */
 753         ext4_commit_super(sbi->s_sb);
 754         ext4_notify_error_sysfs(sbi);
 755 }
 756
 757 #define ext4_error_ratelimit(sb)                                        \
 758                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 759                              "EXT4-fs error")
 760
 761 void __ext4_error(struct super_block *sb, const char *function,
 762                   unsigned int line, bool force_ro, int error, __u64 block,
 763                   const char *fmt, ...)
 764 {
 765         struct va_format vaf;
 766         va_list args;
 767
 768         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 769                 return;
 770
 771         trace_ext4_error(sb, function, line);
 772         if (ext4_error_ratelimit(sb)) {
 773                 va_start(args, fmt);
 774                 vaf.fmt = fmt;
 775                 vaf.va = &args;
 776                 printk(KERN_CRIT
 777                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 778                        sb->s_id, function, line, current->comm, &vaf);
 779                 va_end(args);
 780         }
 781         fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
 782
 783         ext4_handle_error(sb, force_ro, error, 0, block, function, line);
 784 }
 785
 786 void __ext4_error_inode(struct inode *inode, const char *function,
 787                         unsigned int line, ext4_fsblk_t block, int error,
 788                         const char *fmt, ...)
 789 {
 790         va_list args;
 791         struct va_format vaf;
 792
 793         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 794                 return;
 795
 796         trace_ext4_error(inode->i_sb, function, line);
 797         if (ext4_error_ratelimit(inode->i_sb)) {
 798                 va_start(args, fmt);
 799                 vaf.fmt = fmt;
 800                 vaf.va = &args;
 801                 if (block)
 802                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 803                                "inode #%lu: block %llu: comm %s: %pV\n",
 804                                inode->i_sb->s_id, function, line, inode->i_ino,
 805                                block, current->comm, &vaf);
 806                 else
 807                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 808                                "inode #%lu: comm %s: %pV\n",
 809                                inode->i_sb->s_id, function, line, inode->i_ino,
 810                                current->comm, &vaf);
 811                 va_end(args);
 812         }
 813         fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
 814
 815         ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
 816                           function, line);
 817 }
 818
 819 void __ext4_error_file(struct file *file, const char *function,
 820                        unsigned int line, ext4_fsblk_t block,
 821                        const char *fmt, ...)
 822 {
 823         va_list args;
 824         struct va_format vaf;
 825         struct inode *inode = file_inode(file);
 826         char pathname[80], *path;
 827
 828         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 829                 return;
 830
 831         trace_ext4_error(inode->i_sb, function, line);
 832         if (ext4_error_ratelimit(inode->i_sb)) {
 833                 path = file_path(file, pathname, sizeof(pathname));
 834                 if (IS_ERR(path))
 835                         path = "(unknown)";
 836                 va_start(args, fmt);
 837                 vaf.fmt = fmt;
 838                 vaf.va = &args;
 839                 if (block)
 840                         printk(KERN_CRIT
 841                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 842                                "block %llu: comm %s: path %s: %pV\n",
 843                                inode->i_sb->s_id, function, line, inode->i_ino,
 844                                block, current->comm, path, &vaf);
 845                 else
 846                         printk(KERN_CRIT
 847                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 848                                "comm %s: path %s: %pV\n",
 849                                inode->i_sb->s_id, function, line, inode->i_ino,
 850                                current->comm, path, &vaf);
 851                 va_end(args);
 852         }
 853         fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
 854
 855         ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
 856                           function, line);
 857 }
 858
 859 const char *ext4_decode_error(struct super_block *sb, int errno,
 860                               char nbuf[16])
 861 {
 862         char *errstr = NULL;
 863
 864         switch (errno) {
 865         case -EFSCORRUPTED:
 866                 errstr = "Corrupt filesystem";
 867                 break;
 868         case -EFSBADCRC:
 869                 errstr = "Filesystem failed CRC";
 870                 break;
 871         case -EIO:
 872                 errstr = "IO failure";
 873                 break;
 874         case -ENOMEM:
 875                 errstr = "Out of memory";
 876                 break;
 877         case -EROFS:
 878                 if (!sb || (EXT4_SB(sb)->s_journal &&
 879                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 880                         errstr = "Journal has aborted";
 881                 else
 882                         errstr = "Readonly filesystem";
 883                 break;
 884         default:
 885                 /* If the caller passed in an extra buffer for unknown
 886                  * errors, textualise them now.  Else we just return
 887                  * NULL. */
 888                 if (nbuf) {
 889                         /* Check for truncated error codes... */
 890                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 891                                 errstr = nbuf;
 892                 }
 893                 break;
 894         }
 895
 896         return errstr;
 897 }
 898
 899 /* __ext4_std_error decodes expected errors from journaling functions
 900  * automatically and invokes the appropriate error response.  */
 901
 902 void __ext4_std_error(struct super_block *sb, const char *function,
 903                       unsigned int line, int errno)
 904 {
 905         char nbuf[16];
 906         const char *errstr;
 907
 908         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 909                 return;
 910
 911         /* Special case: if the error is EROFS, and we're not already
 912          * inside a transaction, then there's really no point in logging
 913          * an error. */
 914         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 915                 return;
 916
 917         if (ext4_error_ratelimit(sb)) {
 918                 errstr = ext4_decode_error(sb, errno, nbuf);
 919                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 920                        sb->s_id, function, line, errstr);
 921         }
 922         fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
 923
 924         ext4_handle_error(sb, false, -errno, 0, 0, function, line);
 925 }
 926
 927 void __ext4_msg(struct super_block *sb,
 928                 const char *prefix, const char *fmt, ...)
 929 {
 930         struct va_format vaf;
 931         va_list args;
 932
 933         if (sb) {
 934                 atomic_inc(&EXT4_SB(sb)->s_msg_count);
 935                 if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state),
 936                                   "EXT4-fs"))
 937                         return;
 938         }
 939
 940         va_start(args, fmt);
 941         vaf.fmt = fmt;
 942         vaf.va = &args;
 943         if (sb)
 944                 printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 945         else
 946                 printk("%sEXT4-fs: %pV\n", prefix, &vaf);
 947         va_end(args);
 948 }
 949
 950 static int ext4_warning_ratelimit(struct super_block *sb)
 951 {
 952         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 953         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 954                             "EXT4-fs warning");
 955 }
 956
 957 void __ext4_warning(struct super_block *sb, const char *function,
 958                     unsigned int line, const char *fmt, ...)
 959 {
 960         struct va_format vaf;
 961         va_list args;
 962
 963         if (!ext4_warning_ratelimit(sb))
 964                 return;
 965
 966         va_start(args, fmt);
 967         vaf.fmt = fmt;
 968         vaf.va = &args;
 969         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 970                sb->s_id, function, line, &vaf);
 971         va_end(args);
 972 }
 973
 974 void __ext4_warning_inode(const struct inode *inode, const char *function,
 975                           unsigned int line, const char *fmt, ...)
 976 {
 977         struct va_format vaf;
 978         va_list args;
 979
 980         if (!ext4_warning_ratelimit(inode->i_sb))
 981                 return;
 982
 983         va_start(args, fmt);
 984         vaf.fmt = fmt;
 985         vaf.va = &args;
 986         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 987                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 988                function, line, inode->i_ino, current->comm, &vaf);
 989         va_end(args);
 990 }
 991
 992 void __ext4_grp_locked_error(const char *function, unsigned int line,
 993                              struct super_block *sb, ext4_group_t grp,
 994                              unsigned long ino, ext4_fsblk_t block,
 995                              const char *fmt, ...)
 996 __releases(bitlock)
 997 __acquires(bitlock)
 998 {
 999         struct va_format vaf;
1000         va_list args;
1001
1002         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
1003                 return;
1004
1005         trace_ext4_error(sb, function, line);
1006         if (ext4_error_ratelimit(sb)) {
1007                 va_start(args, fmt);
1008                 vaf.fmt = fmt;
1009                 vaf.va = &args;
1010                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1011                        sb->s_id, function, line, grp);
1012                 if (ino)
1013                         printk(KERN_CONT "inode %lu: ", ino);
1014                 if (block)
1015                         printk(KERN_CONT "block %llu:",
1016                                (unsigned long long) block);
1017                 printk(KERN_CONT "%pV\n", &vaf);
1018                 va_end(args);
1019         }
1020
1021         if (test_opt(sb, ERRORS_CONT)) {
1022                 if (test_opt(sb, WARN_ON_ERROR))
1023                         WARN_ON_ONCE(1);
1024                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
1025                 if (!bdev_read_only(sb->s_bdev)) {
1026                         save_error_info(sb, EFSCORRUPTED, ino, block, function,
1027                                         line);
1028                         schedule_work(&EXT4_SB(sb)->s_error_work);
1029                 }
1030                 return;
1031         }
1032         ext4_unlock_group(sb, grp);
1033         ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1034         /*
1035          * We only get here in the ERRORS_RO case; relocking the group
1036          * may be dangerous, but nothing bad will happen since the
1037          * filesystem will have already been marked read/only and the
1038          * journal has been aborted.  We return 1 as a hint to callers
1039          * who might what to use the return value from
1040          * ext4_grp_locked_error() to distinguish between the
1041          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1042          * aggressively from the ext4 function in question, with a
1043          * more appropriate error code.
1044          */
1045         ext4_lock_group(sb, grp);
1046         return;
1047 }
1048
1049 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1050                                      ext4_group_t group,
1051                                      unsigned int flags)
1052 {
1053         struct ext4_sb_info *sbi = EXT4_SB(sb);
1054         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1055         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1056         int ret;
1057
1058         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1059                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1060                                             &grp->bb_state);
1061                 if (!ret)
1062                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1063                                            grp->bb_free);
1064         }
1065
1066         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1067                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1068                                             &grp->bb_state);
1069                 if (!ret && gdp) {
1070                         int count;
1071
1072                         count = ext4_free_inodes_count(sb, gdp);
1073                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1074                                            count);
1075                 }
1076         }
1077 }
1078
1079 void ext4_update_dynamic_rev(struct super_block *sb)
1080 {
1081         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1082
1083         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1084                 return;
1085
1086         ext4_warning(sb,
1087                      "updating to rev %d because of new feature flag, "
1088                      "running e2fsck is recommended",
1089                      EXT4_DYNAMIC_REV);
1090
1091         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1092         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1093         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1094         /* leave es->s_feature_*compat flags alone */
1095         /* es->s_uuid will be set by e2fsck if empty */
1096
1097         /*
1098          * The rest of the superblock fields should be zero, and if not it
1099          * means they are likely already in use, so leave them alone.  We
1100          * can leave it up to e2fsck to clean up any inconsistencies there.
1101          */
1102 }
1103
1104 /*
1105  * Open the external journal device
1106  */
1107 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1108 {
1109         struct block_device *bdev;
1110
1111         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1112         if (IS_ERR(bdev))
1113                 goto fail;
1114         return bdev;
1115
1116 fail:
1117         ext4_msg(sb, KERN_ERR,
1118                  "failed to open journal device unknown-block(%u,%u) %ld",
1119                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1120         return NULL;
1121 }
1122
1123 /*
1124  * Release the journal device
1125  */
1126 static void ext4_blkdev_put(struct block_device *bdev)
1127 {
1128         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1129 }
1130
1131 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1132 {
1133         struct block_device *bdev;
1134         bdev = sbi->s_journal_bdev;
1135         if (bdev) {
1136                 ext4_blkdev_put(bdev);
1137                 sbi->s_journal_bdev = NULL;
1138         }
1139 }
1140
1141 static inline struct inode *orphan_list_entry(struct list_head *l)
1142 {
1143         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1144 }
1145
1146 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1147 {
1148         struct list_head *l;
1149
1150         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1151                  le32_to_cpu(sbi->s_es->s_last_orphan));
1152
1153         printk(KERN_ERR "sb_info orphan list:\n");
1154         list_for_each(l, &sbi->s_orphan) {
1155                 struct inode *inode = orphan_list_entry(l);
1156                 printk(KERN_ERR "  "
1157                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1158                        inode->i_sb->s_id, inode->i_ino, inode,
1159                        inode->i_mode, inode->i_nlink,
1160                        NEXT_ORPHAN(inode));
1161         }
1162 }
1163
1164 #ifdef CONFIG_QUOTA
1165 static int ext4_quota_off(struct super_block *sb, int type);
1166
1167 static inline void ext4_quota_off_umount(struct super_block *sb)
1168 {
1169         int type;
1170
1171         /* Use our quota_off function to clear inode flags etc. */
1172         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1173                 ext4_quota_off(sb, type);
1174 }
1175
1176 /*
1177  * This is a helper function which is used in the mount/remount
1178  * codepaths (which holds s_umount) to fetch the quota file name.
1179  */
1180 static inline char *get_qf_name(struct super_block *sb,
1181                                 struct ext4_sb_info *sbi,
1182                                 int type)
1183 {
1184         return rcu_dereference_protected(sbi->s_qf_names[type],
1185                                          lockdep_is_held(&sb->s_umount));
1186 }
1187 #else
1188 static inline void ext4_quota_off_umount(struct super_block *sb)
1189 {
1190 }
1191 #endif
1192
1193 static void ext4_put_super(struct super_block *sb)
1194 {
1195         struct ext4_sb_info *sbi = EXT4_SB(sb);
1196         struct ext4_super_block *es = sbi->s_es;
1197         struct buffer_head **group_desc;
1198         struct flex_groups **flex_groups;
1199         int aborted = 0;
1200         int i, err;
1201
1202         ext4_unregister_li_request(sb);
1203         ext4_quota_off_umount(sb);
1204
1205         flush_work(&sbi->s_error_work);
1206         destroy_workqueue(sbi->rsv_conversion_wq);
1207         ext4_release_orphan_info(sb);
1208
1209         /*
1210          * Unregister sysfs before destroying jbd2 journal.
1211          * Since we could still access attr_journal_task attribute via sysfs
1212          * path which could have sbi->s_journal->j_task as NULL
1213          */
1214         ext4_unregister_sysfs(sb);
1215
1216         if (sbi->s_journal) {
1217                 aborted = is_journal_aborted(sbi->s_journal);
1218                 err = jbd2_journal_destroy(sbi->s_journal);
1219                 sbi->s_journal = NULL;
1220                 if ((err < 0) && !aborted) {
1221                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1222                 }
1223         }
1224
1225         ext4_es_unregister_shrinker(sbi);
1226         del_timer_sync(&sbi->s_err_report);
1227         ext4_release_system_zone(sb);
1228         ext4_mb_release(sb);
1229         ext4_ext_release(sb);
1230
1231         if (!sb_rdonly(sb) && !aborted) {
1232                 ext4_clear_feature_journal_needs_recovery(sb);
1233                 ext4_clear_feature_orphan_present(sb);
1234                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1235         }
1236         if (!sb_rdonly(sb))
1237                 ext4_commit_super(sb);
1238
1239         rcu_read_lock();
1240         group_desc = rcu_dereference(sbi->s_group_desc);
1241         for (i = 0; i < sbi->s_gdb_count; i++)
1242                 brelse(group_desc[i]);
1243         kvfree(group_desc);
1244         flex_groups = rcu_dereference(sbi->s_flex_groups);
1245         if (flex_groups) {
1246                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1247                         kvfree(flex_groups[i]);
1248                 kvfree(flex_groups);
1249         }
1250         rcu_read_unlock();
1251         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1252         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1253         percpu_counter_destroy(&sbi->s_dirs_counter);
1254         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1255         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1256         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1257 #ifdef CONFIG_QUOTA
1258         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1259                 kfree(get_qf_name(sb, sbi, i));
1260 #endif
1261
1262         /* Debugging code just in case the in-memory inode orphan list
1263          * isn't empty.  The on-disk one can be non-empty if we've
1264          * detected an error and taken the fs readonly, but the
1265          * in-memory list had better be clean by this point. */
1266         if (!list_empty(&sbi->s_orphan))
1267                 dump_orphan_list(sb, sbi);
1268         ASSERT(list_empty(&sbi->s_orphan));
1269
1270         sync_blockdev(sb->s_bdev);
1271         invalidate_bdev(sb->s_bdev);
1272         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1273                 /*
1274                  * Invalidate the journal device's buffers.  We don't want them
1275                  * floating about in memory - the physical journal device may
1276                  * hotswapped, and it breaks the `ro-after' testing code.
1277                  */
1278                 sync_blockdev(sbi->s_journal_bdev);
1279                 invalidate_bdev(sbi->s_journal_bdev);
1280                 ext4_blkdev_remove(sbi);
1281         }
1282
1283         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1284         sbi->s_ea_inode_cache = NULL;
1285
1286         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1287         sbi->s_ea_block_cache = NULL;
1288
1289         ext4_stop_mmpd(sbi);
1290
1291         brelse(sbi->s_sbh);
1292         sb->s_fs_info = NULL;
1293         /*
1294          * Now that we are completely done shutting down the
1295          * superblock, we need to actually destroy the kobject.
1296          */
1297         kobject_put(&sbi->s_kobj);
1298         wait_for_completion(&sbi->s_kobj_unregister);
1299         if (sbi->s_chksum_driver)
1300                 crypto_free_shash(sbi->s_chksum_driver);
1301         kfree(sbi->s_blockgroup_lock);
1302         fs_put_dax(sbi->s_daxdev);
1303         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1304 #ifdef CONFIG_UNICODE
1305         utf8_unload(sb->s_encoding);
1306 #endif
1307         kfree(sbi);
1308 }
1309
1310 static struct kmem_cache *ext4_inode_cachep;
1311
1312 /*
1313  * Called inside transaction, so use GFP_NOFS
1314  */
1315 static struct inode *ext4_alloc_inode(struct super_block *sb)
1316 {
1317         struct ext4_inode_info *ei;
1318
1319         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1320         if (!ei)
1321                 return NULL;
1322
1323         inode_set_iversion(&ei->vfs_inode, 1);
1324         spin_lock_init(&ei->i_raw_lock);
1325         INIT_LIST_HEAD(&ei->i_prealloc_list);
1326         atomic_set(&ei->i_prealloc_active, 0);
1327         spin_lock_init(&ei->i_prealloc_lock);
1328         ext4_es_init_tree(&ei->i_es_tree);
1329         rwlock_init(&ei->i_es_lock);
1330         INIT_LIST_HEAD(&ei->i_es_list);
1331         ei->i_es_all_nr = 0;
1332         ei->i_es_shk_nr = 0;
1333         ei->i_es_shrink_lblk = 0;
1334         ei->i_reserved_data_blocks = 0;
1335         spin_lock_init(&(ei->i_block_reservation_lock));
1336         ext4_init_pending_tree(&ei->i_pending_tree);
1337 #ifdef CONFIG_QUOTA
1338         ei->i_reserved_quota = 0;
1339         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1340 #endif
1341         ei->jinode = NULL;
1342         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1343         spin_lock_init(&ei->i_completed_io_lock);
1344         ei->i_sync_tid = 0;
1345         ei->i_datasync_tid = 0;
1346         atomic_set(&ei->i_unwritten, 0);
1347         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1348         ext4_fc_init_inode(&ei->vfs_inode);
1349         mutex_init(&ei->i_fc_lock);
1350         return &ei->vfs_inode;
1351 }
1352
1353 static int ext4_drop_inode(struct inode *inode)
1354 {
1355         int drop = generic_drop_inode(inode);
1356
1357         if (!drop)
1358                 drop = fscrypt_drop_inode(inode);
1359
1360         trace_ext4_drop_inode(inode, drop);
1361         return drop;
1362 }
1363
1364 static void ext4_free_in_core_inode(struct inode *inode)
1365 {
1366         fscrypt_free_inode(inode);
1367         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1368                 pr_warn("%s: inode %ld still in fc list",
1369                         __func__, inode->i_ino);
1370         }
1371         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1372 }
1373
1374 static void ext4_destroy_inode(struct inode *inode)
1375 {
1376         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1377                 ext4_msg(inode->i_sb, KERN_ERR,
1378                          "Inode %lu (%p): orphan list check failed!",
1379                          inode->i_ino, EXT4_I(inode));
1380                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1381                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1382                                 true);
1383                 dump_stack();
1384         }
1385
1386         if (EXT4_I(inode)->i_reserved_data_blocks)
1387                 ext4_msg(inode->i_sb, KERN_ERR,
1388                          "Inode %lu (%p): i_reserved_data_blocks (%u) not cleared!",
1389                          inode->i_ino, EXT4_I(inode),
1390                          EXT4_I(inode)->i_reserved_data_blocks);
1391 }
1392
1393 static void init_once(void *foo)
1394 {
1395         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1396
1397         INIT_LIST_HEAD(&ei->i_orphan);
1398         init_rwsem(&ei->xattr_sem);
1399         init_rwsem(&ei->i_data_sem);
1400         inode_init_once(&ei->vfs_inode);
1401         ext4_fc_init_inode(&ei->vfs_inode);
1402 }
1403
1404 static int __init init_inodecache(void)
1405 {
1406         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1407                                 sizeof(struct ext4_inode_info), 0,
1408                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1409                                         SLAB_ACCOUNT),
1410                                 offsetof(struct ext4_inode_info, i_data),
1411                                 sizeof_field(struct ext4_inode_info, i_data),
1412                                 init_once);
1413         if (ext4_inode_cachep == NULL)
1414                 return -ENOMEM;
1415         return 0;
1416 }
1417
1418 static void destroy_inodecache(void)
1419 {
1420         /*
1421          * Make sure all delayed rcu free inodes are flushed before we
1422          * destroy cache.
1423          */
1424         rcu_barrier();
1425         kmem_cache_destroy(ext4_inode_cachep);
1426 }
1427
1428 void ext4_clear_inode(struct inode *inode)
1429 {
1430         ext4_fc_del(inode);
1431         invalidate_inode_buffers(inode);
1432         clear_inode(inode);
1433         ext4_discard_preallocations(inode, 0);
1434         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1435         dquot_drop(inode);
1436         if (EXT4_I(inode)->jinode) {
1437                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1438                                                EXT4_I(inode)->jinode);
1439                 jbd2_free_inode(EXT4_I(inode)->jinode);
1440                 EXT4_I(inode)->jinode = NULL;
1441         }
1442         fscrypt_put_encryption_info(inode);
1443         fsverity_cleanup_inode(inode);
1444 }
1445
1446 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1447                                         u64 ino, u32 generation)
1448 {
1449         struct inode *inode;
1450
1451         /*
1452          * Currently we don't know the generation for parent directory, so
1453          * a generation of 0 means "accept any"
1454          */
1455         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1456         if (IS_ERR(inode))
1457                 return ERR_CAST(inode);
1458         if (generation && inode->i_generation != generation) {
1459                 iput(inode);
1460                 return ERR_PTR(-ESTALE);
1461         }
1462
1463         return inode;
1464 }
1465
1466 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1467                                         int fh_len, int fh_type)
1468 {
1469         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1470                                     ext4_nfs_get_inode);
1471 }
1472
1473 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1474                                         int fh_len, int fh_type)
1475 {
1476         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1477                                     ext4_nfs_get_inode);
1478 }
1479
1480 static int ext4_nfs_commit_metadata(struct inode *inode)
1481 {
1482         struct writeback_control wbc = {
1483                 .sync_mode = WB_SYNC_ALL
1484         };
1485
1486         trace_ext4_nfs_commit_metadata(inode);
1487         return ext4_write_inode(inode, &wbc);
1488 }
1489
1490 #ifdef CONFIG_FS_ENCRYPTION
1491 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1492 {
1493         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1494                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1495 }
1496
1497 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1498                                                         void *fs_data)
1499 {
1500         handle_t *handle = fs_data;
1501         int res, res2, credits, retries = 0;
1502
1503         /*
1504          * Encrypting the root directory is not allowed because e2fsck expects
1505          * lost+found to exist and be unencrypted, and encrypting the root
1506          * directory would imply encrypting the lost+found directory as well as
1507          * the filename "lost+found" itself.
1508          */
1509         if (inode->i_ino == EXT4_ROOT_INO)
1510                 return -EPERM;
1511
1512         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1513                 return -EINVAL;
1514
1515         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1516                 return -EOPNOTSUPP;
1517
1518         res = ext4_convert_inline_data(inode);
1519         if (res)
1520                 return res;
1521
1522         /*
1523          * If a journal handle was specified, then the encryption context is
1524          * being set on a new inode via inheritance and is part of a larger
1525          * transaction to create the inode.  Otherwise the encryption context is
1526          * being set on an existing inode in its own transaction.  Only in the
1527          * latter case should the "retry on ENOSPC" logic be used.
1528          */
1529
1530         if (handle) {
1531                 res = ext4_xattr_set_handle(handle, inode,
1532                                             EXT4_XATTR_INDEX_ENCRYPTION,
1533                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1534                                             ctx, len, 0);
1535                 if (!res) {
1536                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1537                         ext4_clear_inode_state(inode,
1538                                         EXT4_STATE_MAY_INLINE_DATA);
1539                         /*
1540                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1541                          * S_DAX may be disabled
1542                          */
1543                         ext4_set_inode_flags(inode, false);
1544                 }
1545                 return res;
1546         }
1547
1548         res = dquot_initialize(inode);
1549         if (res)
1550                 return res;
1551 retry:
1552         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1553                                      &credits);
1554         if (res)
1555                 return res;
1556
1557         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1558         if (IS_ERR(handle))
1559                 return PTR_ERR(handle);
1560
1561         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1562                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1563                                     ctx, len, 0);
1564         if (!res) {
1565                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1566                 /*
1567                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1568                  * S_DAX may be disabled
1569                  */
1570                 ext4_set_inode_flags(inode, false);
1571                 res = ext4_mark_inode_dirty(handle, inode);
1572                 if (res)
1573                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1574         }
1575         res2 = ext4_journal_stop(handle);
1576
1577         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1578                 goto retry;
1579         if (!res)
1580                 res = res2;
1581         return res;
1582 }
1583
1584 static const union fscrypt_policy *ext4_get_dummy_policy(struct super_block *sb)
1585 {
1586         return EXT4_SB(sb)->s_dummy_enc_policy.policy;
1587 }
1588
1589 static bool ext4_has_stable_inodes(struct super_block *sb)
1590 {
1591         return ext4_has_feature_stable_inodes(sb);
1592 }
1593
1594 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1595                                        int *ino_bits_ret, int *lblk_bits_ret)
1596 {
1597         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1598         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1599 }
1600
1601 static const struct fscrypt_operations ext4_cryptops = {
1602         .key_prefix             = "ext4:",
1603         .get_context            = ext4_get_context,
1604         .set_context            = ext4_set_context,
1605         .get_dummy_policy       = ext4_get_dummy_policy,
1606         .empty_dir              = ext4_empty_dir,
1607         .has_stable_inodes      = ext4_has_stable_inodes,
1608         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1609 };
1610 #endif
1611
1612 #ifdef CONFIG_QUOTA
1613 static const char * const quotatypes[] = INITQFNAMES;
1614 #define QTYPE2NAME(t) (quotatypes[t])
1615
1616 static int ext4_write_dquot(struct dquot *dquot);
1617 static int ext4_acquire_dquot(struct dquot *dquot);
1618 static int ext4_release_dquot(struct dquot *dquot);
1619 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1620 static int ext4_write_info(struct super_block *sb, int type);
1621 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1622                          const struct path *path);
1623 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1624                                size_t len, loff_t off);
1625 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1626                                 const char *data, size_t len, loff_t off);
1627 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1628                              unsigned int flags);
1629
1630 static struct dquot **ext4_get_dquots(struct inode *inode)
1631 {
1632         return EXT4_I(inode)->i_dquot;
1633 }
1634
1635 static const struct dquot_operations ext4_quota_operations = {
1636         .get_reserved_space     = ext4_get_reserved_space,
1637         .write_dquot            = ext4_write_dquot,
1638         .acquire_dquot          = ext4_acquire_dquot,
1639         .release_dquot          = ext4_release_dquot,
1640         .mark_dirty             = ext4_mark_dquot_dirty,
1641         .write_info             = ext4_write_info,
1642         .alloc_dquot            = dquot_alloc,
1643         .destroy_dquot          = dquot_destroy,
1644         .get_projid             = ext4_get_projid,
1645         .get_inode_usage        = ext4_get_inode_usage,
1646         .get_next_id            = dquot_get_next_id,
1647 };
1648
1649 static const struct quotactl_ops ext4_qctl_operations = {
1650         .quota_on       = ext4_quota_on,
1651         .quota_off      = ext4_quota_off,
1652         .quota_sync     = dquot_quota_sync,
1653         .get_state      = dquot_get_state,
1654         .set_info       = dquot_set_dqinfo,
1655         .get_dqblk      = dquot_get_dqblk,
1656         .set_dqblk      = dquot_set_dqblk,
1657         .get_nextdqblk  = dquot_get_next_dqblk,
1658 };
1659 #endif
1660
1661 static const struct super_operations ext4_sops = {
1662         .alloc_inode    = ext4_alloc_inode,
1663         .free_inode     = ext4_free_in_core_inode,
1664         .destroy_inode  = ext4_destroy_inode,
1665         .write_inode    = ext4_write_inode,
1666         .dirty_inode    = ext4_dirty_inode,
1667         .drop_inode     = ext4_drop_inode,
1668         .evict_inode    = ext4_evict_inode,
1669         .put_super      = ext4_put_super,
1670         .sync_fs        = ext4_sync_fs,
1671         .freeze_fs      = ext4_freeze,
1672         .unfreeze_fs    = ext4_unfreeze,
1673         .statfs         = ext4_statfs,
1674         .show_options   = ext4_show_options,
1675 #ifdef CONFIG_QUOTA
1676         .quota_read     = ext4_quota_read,
1677         .quota_write    = ext4_quota_write,
1678         .get_dquots     = ext4_get_dquots,
1679 #endif
1680 };
1681
1682 static const struct export_operations ext4_export_ops = {
1683         .fh_to_dentry = ext4_fh_to_dentry,
1684         .fh_to_parent = ext4_fh_to_parent,
1685         .get_parent = ext4_get_parent,
1686         .commit_metadata = ext4_nfs_commit_metadata,
1687 };
1688
1689 enum {
1690         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1691         Opt_resgid, Opt_resuid, Opt_sb,
1692         Opt_nouid32, Opt_debug, Opt_removed,
1693         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1694         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1695         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1696         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1697         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1698         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1699         Opt_inlinecrypt,
1700         Opt_usrjquota, Opt_grpjquota, Opt_quota,
1701         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1702         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1703         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1704         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1705         Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
1706         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1707         Opt_inode_readahead_blks, Opt_journal_ioprio,
1708         Opt_dioread_nolock, Opt_dioread_lock,
1709         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1710         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1711         Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1712         Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
1713 #ifdef CONFIG_EXT4_DEBUG
1714         Opt_fc_debug_max_replay, Opt_fc_debug_force
1715 #endif
1716 };
1717
1718 static const struct constant_table ext4_param_errors[] = {
1719         {"continue",    EXT4_MOUNT_ERRORS_CONT},
1720         {"panic",       EXT4_MOUNT_ERRORS_PANIC},
1721         {"remount-ro",  EXT4_MOUNT_ERRORS_RO},
1722         {}
1723 };
1724
1725 static const struct constant_table ext4_param_data[] = {
1726         {"journal",     EXT4_MOUNT_JOURNAL_DATA},
1727         {"ordered",     EXT4_MOUNT_ORDERED_DATA},
1728         {"writeback",   EXT4_MOUNT_WRITEBACK_DATA},
1729         {}
1730 };
1731
1732 static const struct constant_table ext4_param_data_err[] = {
1733         {"abort",       Opt_data_err_abort},
1734         {"ignore",      Opt_data_err_ignore},
1735         {}
1736 };
1737
1738 static const struct constant_table ext4_param_jqfmt[] = {
1739         {"vfsold",      QFMT_VFS_OLD},
1740         {"vfsv0",       QFMT_VFS_V0},
1741         {"vfsv1",       QFMT_VFS_V1},
1742         {}
1743 };
1744
1745 static const struct constant_table ext4_param_dax[] = {
1746         {"always",      Opt_dax_always},
1747         {"inode",       Opt_dax_inode},
1748         {"never",       Opt_dax_never},
1749         {}
1750 };
1751
1752 /* String parameter that allows empty argument */
1753 #define fsparam_string_empty(NAME, OPT) \
1754         __fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
1755
1756 /*
1757  * Mount option specification
1758  * We don't use fsparam_flag_no because of the way we set the
1759  * options and the way we show them in _ext4_show_options(). To
1760  * keep the changes to a minimum, let's keep the negative options
1761  * separate for now.
1762  */
1763 static const struct fs_parameter_spec ext4_param_specs[] = {
1764         fsparam_flag    ("bsddf",               Opt_bsd_df),
1765         fsparam_flag    ("minixdf",             Opt_minix_df),
1766         fsparam_flag    ("grpid",               Opt_grpid),
1767         fsparam_flag    ("bsdgroups",           Opt_grpid),
1768         fsparam_flag    ("nogrpid",             Opt_nogrpid),
1769         fsparam_flag    ("sysvgroups",          Opt_nogrpid),
1770         fsparam_u32     ("resgid",              Opt_resgid),
1771         fsparam_u32     ("resuid",              Opt_resuid),
1772         fsparam_u32     ("sb",                  Opt_sb),
1773         fsparam_enum    ("errors",              Opt_errors, ext4_param_errors),
1774         fsparam_flag    ("nouid32",             Opt_nouid32),
1775         fsparam_flag    ("debug",               Opt_debug),
1776         fsparam_flag    ("oldalloc",            Opt_removed),
1777         fsparam_flag    ("orlov",               Opt_removed),
1778         fsparam_flag    ("user_xattr",          Opt_user_xattr),
1779         fsparam_flag    ("nouser_xattr",        Opt_nouser_xattr),
1780         fsparam_flag    ("acl",                 Opt_acl),
1781         fsparam_flag    ("noacl",               Opt_noacl),
1782         fsparam_flag    ("norecovery",          Opt_noload),
1783         fsparam_flag    ("noload",              Opt_noload),
1784         fsparam_flag    ("bh",                  Opt_removed),
1785         fsparam_flag    ("nobh",                Opt_removed),
1786         fsparam_u32     ("commit",              Opt_commit),
1787         fsparam_u32     ("min_batch_time",      Opt_min_batch_time),
1788         fsparam_u32     ("max_batch_time",      Opt_max_batch_time),
1789         fsparam_u32     ("journal_dev",         Opt_journal_dev),
1790         fsparam_bdev    ("journal_path",        Opt_journal_path),
1791         fsparam_flag    ("journal_checksum",    Opt_journal_checksum),
1792         fsparam_flag    ("nojournal_checksum",  Opt_nojournal_checksum),
1793         fsparam_flag    ("journal_async_commit",Opt_journal_async_commit),
1794         fsparam_flag    ("abort",               Opt_abort),
1795         fsparam_enum    ("data",                Opt_data, ext4_param_data),
1796         fsparam_enum    ("data_err",            Opt_data_err,
1797                                                 ext4_param_data_err),
1798         fsparam_string_empty
1799                         ("usrjquota",           Opt_usrjquota),
1800         fsparam_string_empty
1801                         ("grpjquota",           Opt_grpjquota),
1802         fsparam_enum    ("jqfmt",               Opt_jqfmt, ext4_param_jqfmt),
1803         fsparam_flag    ("grpquota",            Opt_grpquota),
1804         fsparam_flag    ("quota",               Opt_quota),
1805         fsparam_flag    ("noquota",             Opt_noquota),
1806         fsparam_flag    ("usrquota",            Opt_usrquota),
1807         fsparam_flag    ("prjquota",            Opt_prjquota),
1808         fsparam_flag    ("barrier",             Opt_barrier),
1809         fsparam_u32     ("barrier",             Opt_barrier),
1810         fsparam_flag    ("nobarrier",           Opt_nobarrier),
1811         fsparam_flag    ("i_version",           Opt_i_version),
1812         fsparam_flag    ("dax",                 Opt_dax),
1813         fsparam_enum    ("dax",                 Opt_dax_type, ext4_param_dax),
1814         fsparam_u32     ("stripe",              Opt_stripe),
1815         fsparam_flag    ("delalloc",            Opt_delalloc),
1816         fsparam_flag    ("nodelalloc",          Opt_nodelalloc),
1817         fsparam_flag    ("warn_on_error",       Opt_warn_on_error),
1818         fsparam_flag    ("nowarn_on_error",     Opt_nowarn_on_error),
1819         fsparam_u32     ("debug_want_extra_isize",
1820                                                 Opt_debug_want_extra_isize),
1821         fsparam_flag    ("mblk_io_submit",      Opt_removed),
1822         fsparam_flag    ("nomblk_io_submit",    Opt_removed),
1823         fsparam_flag    ("block_validity",      Opt_block_validity),
1824         fsparam_flag    ("noblock_validity",    Opt_noblock_validity),
1825         fsparam_u32     ("inode_readahead_blks",
1826                                                 Opt_inode_readahead_blks),
1827         fsparam_u32     ("journal_ioprio",      Opt_journal_ioprio),
1828         fsparam_u32     ("auto_da_alloc",       Opt_auto_da_alloc),
1829         fsparam_flag    ("auto_da_alloc",       Opt_auto_da_alloc),
1830         fsparam_flag    ("noauto_da_alloc",     Opt_noauto_da_alloc),
1831         fsparam_flag    ("dioread_nolock",      Opt_dioread_nolock),
1832         fsparam_flag    ("nodioread_nolock",    Opt_dioread_lock),
1833         fsparam_flag    ("dioread_lock",        Opt_dioread_lock),
1834         fsparam_flag    ("discard",             Opt_discard),
1835         fsparam_flag    ("nodiscard",           Opt_nodiscard),
1836         fsparam_u32     ("init_itable",         Opt_init_itable),
1837         fsparam_flag    ("init_itable",         Opt_init_itable),
1838         fsparam_flag    ("noinit_itable",       Opt_noinit_itable),
1839 #ifdef CONFIG_EXT4_DEBUG
1840         fsparam_flag    ("fc_debug_force",      Opt_fc_debug_force),
1841         fsparam_u32     ("fc_debug_max_replay", Opt_fc_debug_max_replay),
1842 #endif
1843         fsparam_u32     ("max_dir_size_kb",     Opt_max_dir_size_kb),
1844         fsparam_flag    ("test_dummy_encryption",
1845                                                 Opt_test_dummy_encryption),
1846         fsparam_string  ("test_dummy_encryption",
1847                                                 Opt_test_dummy_encryption),
1848         fsparam_flag    ("inlinecrypt",         Opt_inlinecrypt),
1849         fsparam_flag    ("nombcache",           Opt_nombcache),
1850         fsparam_flag    ("no_mbcache",          Opt_nombcache), /* for backward compatibility */
1851         fsparam_flag    ("prefetch_block_bitmaps",
1852                                                 Opt_removed),
1853         fsparam_flag    ("no_prefetch_block_bitmaps",
1854                                                 Opt_no_prefetch_block_bitmaps),
1855         fsparam_s32     ("mb_optimize_scan",    Opt_mb_optimize_scan),
1856         fsparam_string  ("check",               Opt_removed),   /* mount option from ext2/3 */
1857         fsparam_flag    ("nocheck",             Opt_removed),   /* mount option from ext2/3 */
1858         fsparam_flag    ("reservation",         Opt_removed),   /* mount option from ext2/3 */
1859         fsparam_flag    ("noreservation",       Opt_removed),   /* mount option from ext2/3 */
1860         fsparam_u32     ("journal",             Opt_removed),   /* mount option from ext2/3 */
1861         {}
1862 };
1863
1864 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1865 #define DEFAULT_MB_OPTIMIZE_SCAN        (-1)
1866
1867 static const char deprecated_msg[] =
1868         "Mount option \"%s\" will be removed by %s\n"
1869         "Contact [email protected] if you think we should keep it.\n";
1870
1871 #define MOPT_SET        0x0001
1872 #define MOPT_CLEAR      0x0002
1873 #define MOPT_NOSUPPORT  0x0004
1874 #define MOPT_EXPLICIT   0x0008
1875 #ifdef CONFIG_QUOTA
1876 #define MOPT_Q          0
1877 #define MOPT_QFMT       0x0010
1878 #else
1879 #define MOPT_Q          MOPT_NOSUPPORT
1880 #define MOPT_QFMT       MOPT_NOSUPPORT
1881 #endif
1882 #define MOPT_NO_EXT2    0x0020
1883 #define MOPT_NO_EXT3    0x0040
1884 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1885 #define MOPT_SKIP       0x0080
1886 #define MOPT_2          0x0100
1887
1888 static const struct mount_opts {
1889         int     token;
1890         int     mount_opt;
1891         int     flags;
1892 } ext4_mount_opts[] = {
1893         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1894         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1895         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1896         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1897         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1898         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1899         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1900          MOPT_EXT4_ONLY | MOPT_SET},
1901         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1902          MOPT_EXT4_ONLY | MOPT_CLEAR},
1903         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1904         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1905         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1906          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1907         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1908          MOPT_EXT4_ONLY | MOPT_CLEAR},
1909         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1910         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1911         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1912          MOPT_EXT4_ONLY | MOPT_CLEAR},
1913         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1914          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1915         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1916                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1917          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1918         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1919         {Opt_data_err, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_NO_EXT2},
1920         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1921         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1922         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1923         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1924         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1925         {Opt_dax_type, 0, MOPT_EXT4_ONLY},
1926         {Opt_journal_dev, 0, MOPT_NO_EXT2},
1927         {Opt_journal_path, 0, MOPT_NO_EXT2},
1928         {Opt_journal_ioprio, 0, MOPT_NO_EXT2},
1929         {Opt_data, 0, MOPT_NO_EXT2},
1930         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1931         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1932 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1933         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1934         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1935 #else
1936         {Opt_acl, 0, MOPT_NOSUPPORT},
1937         {Opt_noacl, 0, MOPT_NOSUPPORT},
1938 #endif
1939         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1940         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1941         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1942         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1943                                                         MOPT_SET | MOPT_Q},
1944         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1945                                                         MOPT_SET | MOPT_Q},
1946         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1947                                                         MOPT_SET | MOPT_Q},
1948         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1949                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1950                                                         MOPT_CLEAR | MOPT_Q},
1951         {Opt_usrjquota, 0, MOPT_Q},
1952         {Opt_grpjquota, 0, MOPT_Q},
1953         {Opt_jqfmt, 0, MOPT_QFMT},
1954         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1955         {Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
1956          MOPT_SET},
1957 #ifdef CONFIG_EXT4_DEBUG
1958         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1959          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1960 #endif
1961         {Opt_err, 0, 0}
1962 };
1963
1964 #ifdef CONFIG_UNICODE
1965 static const struct ext4_sb_encodings {
1966         __u16 magic;
1967         char *name;
1968         unsigned int version;
1969 } ext4_sb_encoding_map[] = {
1970         {EXT4_ENC_UTF8_12_1, "utf8", UNICODE_AGE(12, 1, 0)},
1971 };
1972
1973 static const struct ext4_sb_encodings *
1974 ext4_sb_read_encoding(const struct ext4_super_block *es)
1975 {
1976         __u16 magic = le16_to_cpu(es->s_encoding);
1977         int i;
1978
1979         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1980                 if (magic == ext4_sb_encoding_map[i].magic)
1981                         return &ext4_sb_encoding_map[i];
1982
1983         return NULL;
1984 }
1985 #endif
1986
1987 static int ext4_set_test_dummy_encryption(struct super_block *sb, char *arg)
1988 {
1989 #ifdef CONFIG_FS_ENCRYPTION
1990         struct ext4_sb_info *sbi = EXT4_SB(sb);
1991         int err;
1992
1993         err = fscrypt_set_test_dummy_encryption(sb, arg,
1994                                                 &sbi->s_dummy_enc_policy);
1995         if (err) {
1996                 ext4_msg(sb, KERN_WARNING,
1997                          "Error while setting test dummy encryption [%d]", err);
1998                 return err;
1999         }
2000         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2001 #endif
2002         return 0;
2003 }
2004
2005 #define EXT4_SPEC_JQUOTA                        (1 <<  0)
2006 #define EXT4_SPEC_JQFMT                         (1 <<  1)
2007 #define EXT4_SPEC_DATAJ                         (1 <<  2)
2008 #define EXT4_SPEC_SB_BLOCK                      (1 <<  3)
2009 #define EXT4_SPEC_JOURNAL_DEV                   (1 <<  4)
2010 #define EXT4_SPEC_JOURNAL_IOPRIO                (1 <<  5)
2011 #define EXT4_SPEC_DUMMY_ENCRYPTION              (1 <<  6)
2012 #define EXT4_SPEC_s_want_extra_isize            (1 <<  7)
2013 #define EXT4_SPEC_s_max_batch_time              (1 <<  8)
2014 #define EXT4_SPEC_s_min_batch_time              (1 <<  9)
2015 #define EXT4_SPEC_s_inode_readahead_blks        (1 << 10)
2016 #define EXT4_SPEC_s_li_wait_mult                (1 << 11)
2017 #define EXT4_SPEC_s_max_dir_size_kb             (1 << 12)
2018 #define EXT4_SPEC_s_stripe                      (1 << 13)
2019 #define EXT4_SPEC_s_resuid                      (1 << 14)
2020 #define EXT4_SPEC_s_resgid                      (1 << 15)
2021 #define EXT4_SPEC_s_commit_interval             (1 << 16)
2022 #define EXT4_SPEC_s_fc_debug_max_replay         (1 << 17)
2023 #define EXT4_SPEC_s_sb_block                    (1 << 18)
2024
2025 struct ext4_fs_context {
2026         char            *s_qf_names[EXT4_MAXQUOTAS];
2027         char            *test_dummy_enc_arg;
2028         int             s_jquota_fmt;   /* Format of quota to use */
2029         int             mb_optimize_scan;
2030 #ifdef CONFIG_EXT4_DEBUG
2031         int s_fc_debug_max_replay;
2032 #endif
2033         unsigned short  qname_spec;
2034         unsigned long   vals_s_flags;   /* Bits to set in s_flags */
2035         unsigned long   mask_s_flags;   /* Bits changed in s_flags */
2036         unsigned long   journal_devnum;
2037         unsigned long   s_commit_interval;
2038         unsigned long   s_stripe;
2039         unsigned int    s_inode_readahead_blks;
2040         unsigned int    s_want_extra_isize;
2041         unsigned int    s_li_wait_mult;
2042         unsigned int    s_max_dir_size_kb;
2043         unsigned int    journal_ioprio;
2044         unsigned int    vals_s_mount_opt;
2045         unsigned int    mask_s_mount_opt;
2046         unsigned int    vals_s_mount_opt2;
2047         unsigned int    mask_s_mount_opt2;
2048         unsigned int    vals_s_mount_flags;
2049         unsigned int    mask_s_mount_flags;
2050         unsigned int    opt_flags;      /* MOPT flags */
2051         unsigned int    spec;
2052         u32             s_max_batch_time;
2053         u32             s_min_batch_time;
2054         kuid_t          s_resuid;
2055         kgid_t          s_resgid;
2056         ext4_fsblk_t    s_sb_block;
2057 };
2058
2059 static void ext4_fc_free(struct fs_context *fc)
2060 {
2061         struct ext4_fs_context *ctx = fc->fs_private;
2062         int i;
2063
2064         if (!ctx)
2065                 return;
2066
2067         for (i = 0; i < EXT4_MAXQUOTAS; i++)
2068                 kfree(ctx->s_qf_names[i]);
2069
2070         kfree(ctx->test_dummy_enc_arg);
2071         kfree(ctx);
2072 }
2073
2074 int ext4_init_fs_context(struct fs_context *fc)
2075 {
2076         struct ext4_fs_context *ctx;
2077
2078         ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2079         if (!ctx)
2080                 return -ENOMEM;
2081
2082         fc->fs_private = ctx;
2083         fc->ops = &ext4_context_ops;
2084
2085         return 0;
2086 }
2087
2088 #ifdef CONFIG_QUOTA
2089 /*
2090  * Note the name of the specified quota file.
2091  */
2092 static int note_qf_name(struct fs_context *fc, int qtype,
2093                        struct fs_parameter *param)
2094 {
2095         struct ext4_fs_context *ctx = fc->fs_private;
2096         char *qname;
2097
2098         if (param->size < 1) {
2099                 ext4_msg(NULL, KERN_ERR, "Missing quota name");
2100                 return -EINVAL;
2101         }
2102         if (strchr(param->string, '/')) {
2103                 ext4_msg(NULL, KERN_ERR,
2104                          "quotafile must be on filesystem root");
2105                 return -EINVAL;
2106         }
2107         if (ctx->s_qf_names[qtype]) {
2108                 if (strcmp(ctx->s_qf_names[qtype], param->string) != 0) {
2109                         ext4_msg(NULL, KERN_ERR,
2110                                  "%s quota file already specified",
2111                                  QTYPE2NAME(qtype));
2112                         return -EINVAL;
2113                 }
2114                 return 0;
2115         }
2116
2117         qname = kmemdup_nul(param->string, param->size, GFP_KERNEL);
2118         if (!qname) {
2119                 ext4_msg(NULL, KERN_ERR,
2120                          "Not enough memory for storing quotafile name");
2121                 return -ENOMEM;
2122         }
2123         ctx->s_qf_names[qtype] = qname;
2124         ctx->qname_spec |= 1 << qtype;
2125         ctx->spec |= EXT4_SPEC_JQUOTA;
2126         return 0;
2127 }
2128
2129 /*
2130  * Clear the name of the specified quota file.
2131  */
2132 static int unnote_qf_name(struct fs_context *fc, int qtype)
2133 {
2134         struct ext4_fs_context *ctx = fc->fs_private;
2135
2136         if (ctx->s_qf_names[qtype])
2137                 kfree(ctx->s_qf_names[qtype]);
2138
2139         ctx->s_qf_names[qtype] = NULL;
2140         ctx->qname_spec |= 1 << qtype;
2141         ctx->spec |= EXT4_SPEC_JQUOTA;
2142         return 0;
2143 }
2144 #endif
2145
2146 #define EXT4_SET_CTX(name)                                              \
2147 static inline void ctx_set_##name(struct ext4_fs_context *ctx,          \
2148                                   unsigned long flag)                   \
2149 {                                                                       \
2150         ctx->mask_s_##name |= flag;                                     \
2151         ctx->vals_s_##name |= flag;                                     \
2152 }                                                                       \
2153 static inline void ctx_clear_##name(struct ext4_fs_context *ctx,        \
2154                                     unsigned long flag)                 \
2155 {                                                                       \
2156         ctx->mask_s_##name |= flag;                                     \
2157         ctx->vals_s_##name &= ~flag;                                    \
2158 }                                                                       \
2159 static inline unsigned long                                             \
2160 ctx_test_##name(struct ext4_fs_context *ctx, unsigned long flag)        \
2161 {                                                                       \
2162         return (ctx->vals_s_##name & flag);                             \
2163 }                                                                       \
2164
2165 EXT4_SET_CTX(flags);
2166 EXT4_SET_CTX(mount_opt);
2167 EXT4_SET_CTX(mount_opt2);
2168 EXT4_SET_CTX(mount_flags);
2169
2170 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
2171 {
2172         struct ext4_fs_context *ctx = fc->fs_private;
2173         struct fs_parse_result result;
2174         const struct mount_opts *m;
2175         int is_remount;
2176         kuid_t uid;
2177         kgid_t gid;
2178         int token;
2179
2180         token = fs_parse(fc, ext4_param_specs, param, &result);
2181         if (token < 0)
2182                 return token;
2183         is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2184
2185         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2186                 if (token == m->token)
2187                         break;
2188
2189         ctx->opt_flags |= m->flags;
2190
2191         if (m->flags & MOPT_EXPLICIT) {
2192                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2193                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_EXPLICIT_DELALLOC);
2194                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2195                         ctx_set_mount_opt2(ctx,
2196                                        EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM);
2197                 } else
2198                         return -EINVAL;
2199         }
2200
2201         if (m->flags & MOPT_NOSUPPORT) {
2202                 ext4_msg(NULL, KERN_ERR, "%s option not supported",
2203                          param->key);
2204                 return 0;
2205         }
2206
2207         switch (token) {
2208 #ifdef CONFIG_QUOTA
2209         case Opt_usrjquota:
2210                 if (!*param->string)
2211                         return unnote_qf_name(fc, USRQUOTA);
2212                 else
2213                         return note_qf_name(fc, USRQUOTA, param);
2214         case Opt_grpjquota:
2215                 if (!*param->string)
2216                         return unnote_qf_name(fc, GRPQUOTA);
2217                 else
2218                         return note_qf_name(fc, GRPQUOTA, param);
2219 #endif
2220         case Opt_noacl:
2221         case Opt_nouser_xattr:
2222                 ext4_msg(NULL, KERN_WARNING, deprecated_msg, param->key, "3.5");
2223                 break;
2224         case Opt_sb:
2225                 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2226                         ext4_msg(NULL, KERN_WARNING,
2227                                  "Ignoring %s option on remount", param->key);
2228                 } else {
2229                         ctx->s_sb_block = result.uint_32;
2230                         ctx->spec |= EXT4_SPEC_s_sb_block;
2231                 }
2232                 return 0;
2233         case Opt_removed:
2234                 ext4_msg(NULL, KERN_WARNING, "Ignoring removed %s option",
2235                          param->key);
2236                 return 0;
2237         case Opt_abort:
2238                 ctx_set_mount_flags(ctx, EXT4_MF_FS_ABORTED);
2239                 return 0;
2240         case Opt_i_version:
2241                 ext4_msg(NULL, KERN_WARNING, deprecated_msg, param->key, "5.20");
2242                 ext4_msg(NULL, KERN_WARNING, "Use iversion instead\n");
2243                 ctx_set_flags(ctx, SB_I_VERSION);
2244                 return 0;
2245         case Opt_inlinecrypt:
2246 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2247                 ctx_set_flags(ctx, SB_INLINECRYPT);
2248 #else
2249                 ext4_msg(NULL, KERN_ERR, "inline encryption not supported");
2250 #endif
2251                 return 0;
2252         case Opt_errors:
2253                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_ERRORS_MASK);
2254                 ctx_set_mount_opt(ctx, result.uint_32);
2255                 return 0;
2256 #ifdef CONFIG_QUOTA
2257         case Opt_jqfmt:
2258                 ctx->s_jquota_fmt = result.uint_32;
2259                 ctx->spec |= EXT4_SPEC_JQFMT;
2260                 return 0;
2261 #endif
2262         case Opt_data:
2263                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2264                 ctx_set_mount_opt(ctx, result.uint_32);
2265                 ctx->spec |= EXT4_SPEC_DATAJ;
2266                 return 0;
2267         case Opt_commit:
2268                 if (result.uint_32 == 0)
2269                         ctx->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE;
2270                 else if (result.uint_32 > INT_MAX / HZ) {
2271                         ext4_msg(NULL, KERN_ERR,
2272                                  "Invalid commit interval %d, "
2273                                  "must be smaller than %d",
2274                                  result.uint_32, INT_MAX / HZ);
2275                         return -EINVAL;
2276                 }
2277                 ctx->s_commit_interval = HZ * result.uint_32;
2278                 ctx->spec |= EXT4_SPEC_s_commit_interval;
2279                 return 0;
2280         case Opt_debug_want_extra_isize:
2281                 if ((result.uint_32 & 1) || (result.uint_32 < 4)) {
2282                         ext4_msg(NULL, KERN_ERR,
2283                                  "Invalid want_extra_isize %d", result.uint_32);
2284                         return -EINVAL;
2285                 }
2286                 ctx->s_want_extra_isize = result.uint_32;
2287                 ctx->spec |= EXT4_SPEC_s_want_extra_isize;
2288                 return 0;
2289         case Opt_max_batch_time:
2290                 ctx->s_max_batch_time = result.uint_32;
2291                 ctx->spec |= EXT4_SPEC_s_max_batch_time;
2292                 return 0;
2293         case Opt_min_batch_time:
2294                 ctx->s_min_batch_time = result.uint_32;
2295                 ctx->spec |= EXT4_SPEC_s_min_batch_time;
2296                 return 0;
2297         case Opt_inode_readahead_blks:
2298                 if (result.uint_32 &&
2299                     (result.uint_32 > (1 << 30) ||
2300                      !is_power_of_2(result.uint_32))) {
2301                         ext4_msg(NULL, KERN_ERR,
2302                                  "EXT4-fs: inode_readahead_blks must be "
2303                                  "0 or a power of 2 smaller than 2^31");
2304                         return -EINVAL;
2305                 }
2306                 ctx->s_inode_readahead_blks = result.uint_32;
2307                 ctx->spec |= EXT4_SPEC_s_inode_readahead_blks;
2308                 return 0;
2309         case Opt_init_itable:
2310                 ctx_set_mount_opt(ctx, EXT4_MOUNT_INIT_INODE_TABLE);
2311                 ctx->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
2312                 if (param->type == fs_value_is_string)
2313                         ctx->s_li_wait_mult = result.uint_32;
2314                 ctx->spec |= EXT4_SPEC_s_li_wait_mult;
2315                 return 0;
2316         case Opt_max_dir_size_kb:
2317                 ctx->s_max_dir_size_kb = result.uint_32;
2318                 ctx->spec |= EXT4_SPEC_s_max_dir_size_kb;
2319                 return 0;
2320 #ifdef CONFIG_EXT4_DEBUG
2321         case Opt_fc_debug_max_replay:
2322                 ctx->s_fc_debug_max_replay = result.uint_32;
2323                 ctx->spec |= EXT4_SPEC_s_fc_debug_max_replay;
2324                 return 0;
2325 #endif
2326         case Opt_stripe:
2327                 ctx->s_stripe = result.uint_32;
2328                 ctx->spec |= EXT4_SPEC_s_stripe;
2329                 return 0;
2330         case Opt_resuid:
2331                 uid = make_kuid(current_user_ns(), result.uint_32);
2332                 if (!uid_valid(uid)) {
2333                         ext4_msg(NULL, KERN_ERR, "Invalid uid value %d",
2334                                  result.uint_32);
2335                         return -EINVAL;
2336                 }
2337                 ctx->s_resuid = uid;
2338                 ctx->spec |= EXT4_SPEC_s_resuid;
2339                 return 0;
2340         case Opt_resgid:
2341                 gid = make_kgid(current_user_ns(), result.uint_32);
2342                 if (!gid_valid(gid)) {
2343                         ext4_msg(NULL, KERN_ERR, "Invalid gid value %d",
2344                                  result.uint_32);
2345                         return -EINVAL;
2346                 }
2347                 ctx->s_resgid = gid;
2348                 ctx->spec |= EXT4_SPEC_s_resgid;
2349                 return 0;
2350         case Opt_journal_dev:
2351                 if (is_remount) {
2352                         ext4_msg(NULL, KERN_ERR,
2353                                  "Cannot specify journal on remount");
2354                         return -EINVAL;
2355                 }
2356                 ctx->journal_devnum = result.uint_32;
2357                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2358                 return 0;
2359         case Opt_journal_path:
2360         {
2361                 struct inode *journal_inode;
2362                 struct path path;
2363                 int error;
2364
2365                 if (is_remount) {
2366                         ext4_msg(NULL, KERN_ERR,
2367                                  "Cannot specify journal on remount");
2368                         return -EINVAL;
2369                 }
2370
2371                 error = fs_lookup_param(fc, param, 1, &path);
2372                 if (error) {
2373                         ext4_msg(NULL, KERN_ERR, "error: could not find "
2374                                  "journal device path");
2375                         return -EINVAL;
2376                 }
2377
2378                 journal_inode = d_inode(path.dentry);
2379                 ctx->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2380                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2381                 path_put(&path);
2382                 return 0;
2383         }
2384         case Opt_journal_ioprio:
2385                 if (result.uint_32 > 7) {
2386                         ext4_msg(NULL, KERN_ERR, "Invalid journal IO priority"
2387                                  " (must be 0-7)");
2388                         return -EINVAL;
2389                 }
2390                 ctx->journal_ioprio =
2391                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, result.uint_32);
2392                 ctx->spec |= EXT4_SPEC_JOURNAL_IOPRIO;
2393                 return 0;
2394         case Opt_test_dummy_encryption:
2395 #ifdef CONFIG_FS_ENCRYPTION
2396                 if (param->type == fs_value_is_flag) {
2397                         ctx->spec |= EXT4_SPEC_DUMMY_ENCRYPTION;
2398                         ctx->test_dummy_enc_arg = NULL;
2399                         return 0;
2400                 }
2401                 if (*param->string &&
2402                     !(!strcmp(param->string, "v1") ||
2403                       !strcmp(param->string, "v2"))) {
2404                         ext4_msg(NULL, KERN_WARNING,
2405                                  "Value of option \"%s\" is unrecognized",
2406                                  param->key);
2407                         return -EINVAL;
2408                 }
2409                 ctx->spec |= EXT4_SPEC_DUMMY_ENCRYPTION;
2410                 ctx->test_dummy_enc_arg = kmemdup_nul(param->string, param->size,
2411                                                       GFP_KERNEL);
2412 #else
2413                 ext4_msg(NULL, KERN_WARNING,
2414                          "Test dummy encryption mount option ignored");
2415 #endif
2416                 return 0;
2417         case Opt_dax:
2418         case Opt_dax_type:
2419 #ifdef CONFIG_FS_DAX
2420         {
2421                 int type = (token == Opt_dax) ?
2422                            Opt_dax : result.uint_32;
2423
2424                 switch (type) {
2425                 case Opt_dax:
2426                 case Opt_dax_always:
2427                         ctx_set_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2428                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2429                         break;
2430                 case Opt_dax_never:
2431                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2432                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2433                         break;
2434                 case Opt_dax_inode:
2435                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2436                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2437                         /* Strictly for printing options */
2438                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE);
2439                         break;
2440                 }
2441                 return 0;
2442         }
2443 #else
2444                 ext4_msg(NULL, KERN_INFO, "dax option not supported");
2445                 return -EINVAL;
2446 #endif
2447         case Opt_data_err:
2448                 if (result.uint_32 == Opt_data_err_abort)
2449                         ctx_set_mount_opt(ctx, m->mount_opt);
2450                 else if (result.uint_32 == Opt_data_err_ignore)
2451                         ctx_clear_mount_opt(ctx, m->mount_opt);
2452                 return 0;
2453         case Opt_mb_optimize_scan:
2454                 if (result.int_32 != 0 && result.int_32 != 1) {
2455                         ext4_msg(NULL, KERN_WARNING,
2456                                  "mb_optimize_scan should be set to 0 or 1.");
2457                         return -EINVAL;
2458                 }
2459                 ctx->mb_optimize_scan = result.int_32;
2460                 return 0;
2461         }
2462
2463         /*
2464          * At this point we should only be getting options requiring MOPT_SET,
2465          * or MOPT_CLEAR. Anything else is a bug
2466          */
2467         if (m->token == Opt_err) {
2468                 ext4_msg(NULL, KERN_WARNING, "buggy handling of option %s",
2469                          param->key);
2470                 WARN_ON(1);
2471                 return -EINVAL;
2472         }
2473
2474         else {
2475                 unsigned int set = 0;
2476
2477                 if ((param->type == fs_value_is_flag) ||
2478                     result.uint_32 > 0)
2479                         set = 1;
2480
2481                 if (m->flags & MOPT_CLEAR)
2482                         set = !set;
2483                 else if (unlikely(!(m->flags & MOPT_SET))) {
2484                         ext4_msg(NULL, KERN_WARNING,
2485                                  "buggy handling of option %s",
2486                                  param->key);
2487                         WARN_ON(1);
2488                         return -EINVAL;
2489                 }
2490                 if (m->flags & MOPT_2) {
2491                         if (set != 0)
2492                                 ctx_set_mount_opt2(ctx, m->mount_opt);
2493                         else
2494                                 ctx_clear_mount_opt2(ctx, m->mount_opt);
2495                 } else {
2496                         if (set != 0)
2497                                 ctx_set_mount_opt(ctx, m->mount_opt);
2498                         else
2499                                 ctx_clear_mount_opt(ctx, m->mount_opt);
2500                 }
2501         }
2502
2503         return 0;
2504 }
2505
2506 static int parse_options(struct fs_context *fc, char *options)
2507 {
2508         struct fs_parameter param;
2509         int ret;
2510         char *key;
2511
2512         if (!options)
2513                 return 0;
2514
2515         while ((key = strsep(&options, ",")) != NULL) {
2516                 if (*key) {
2517                         size_t v_len = 0;
2518                         char *value = strchr(key, '=');
2519
2520                         param.type = fs_value_is_flag;
2521                         param.string = NULL;
2522
2523                         if (value) {
2524                                 if (value == key)
2525                                         continue;
2526
2527                                 *value++ = 0;
2528                                 v_len = strlen(value);
2529                                 param.string = kmemdup_nul(value, v_len,
2530                                                            GFP_KERNEL);
2531                                 if (!param.string)
2532                                         return -ENOMEM;
2533                                 param.type = fs_value_is_string;
2534                         }
2535
2536                         param.key = key;
2537                         param.size = v_len;
2538
2539                         ret = ext4_parse_param(fc, &param);
2540                         if (param.string)
2541                                 kfree(param.string);
2542                         if (ret < 0)
2543                                 return ret;
2544                 }
2545         }
2546
2547         ret = ext4_validate_options(fc);
2548         if (ret < 0)
2549                 return ret;
2550
2551         return 0;
2552 }
2553
2554 static int parse_apply_sb_mount_options(struct super_block *sb,
2555                                         struct ext4_fs_context *m_ctx)
2556 {
2557         struct ext4_sb_info *sbi = EXT4_SB(sb);
2558         char *s_mount_opts = NULL;
2559         struct ext4_fs_context *s_ctx = NULL;
2560         struct fs_context *fc = NULL;
2561         int ret = -ENOMEM;
2562
2563         if (!sbi->s_es->s_mount_opts[0])
2564                 return 0;
2565
2566         s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
2567                                 sizeof(sbi->s_es->s_mount_opts),
2568                                 GFP_KERNEL);
2569         if (!s_mount_opts)
2570                 return ret;
2571
2572         fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
2573         if (!fc)
2574                 goto out_free;
2575
2576         s_ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2577         if (!s_ctx)
2578                 goto out_free;
2579
2580         fc->fs_private = s_ctx;
2581         fc->s_fs_info = sbi;
2582
2583         ret = parse_options(fc, s_mount_opts);
2584         if (ret < 0)
2585                 goto parse_failed;
2586
2587         ret = ext4_check_opt_consistency(fc, sb);
2588         if (ret < 0) {
2589 parse_failed:
2590                 ext4_msg(sb, KERN_WARNING,
2591                          "failed to parse options in superblock: %s",
2592                          s_mount_opts);
2593                 ret = 0;
2594                 goto out_free;
2595         }
2596
2597         if (s_ctx->spec & EXT4_SPEC_JOURNAL_DEV)
2598                 m_ctx->journal_devnum = s_ctx->journal_devnum;
2599         if (s_ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)
2600                 m_ctx->journal_ioprio = s_ctx->journal_ioprio;
2601
2602         ret = ext4_apply_options(fc, sb);
2603
2604 out_free:
2605         kfree(s_ctx);
2606         kfree(fc);
2607         kfree(s_mount_opts);
2608         return ret;
2609 }
2610
2611 static void ext4_apply_quota_options(struct fs_context *fc,
2612                                      struct super_block *sb)
2613 {
2614 #ifdef CONFIG_QUOTA
2615         bool quota_feature = ext4_has_feature_quota(sb);
2616         struct ext4_fs_context *ctx = fc->fs_private;
2617         struct ext4_sb_info *sbi = EXT4_SB(sb);
2618         char *qname;
2619         int i;
2620
2621         if (quota_feature)
2622                 return;
2623
2624         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2625                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2626                         if (!(ctx->qname_spec & (1 << i)))
2627                                 continue;
2628
2629                         qname = ctx->s_qf_names[i]; /* May be NULL */
2630                         if (qname)
2631                                 set_opt(sb, QUOTA);
2632                         ctx->s_qf_names[i] = NULL;
2633                         qname = rcu_replace_pointer(sbi->s_qf_names[i], qname,
2634                                                 lockdep_is_held(&sb->s_umount));
2635                         if (qname)
2636                                 kfree_rcu(qname);
2637                 }
2638         }
2639
2640         if (ctx->spec & EXT4_SPEC_JQFMT)
2641                 sbi->s_jquota_fmt = ctx->s_jquota_fmt;
2642 #endif
2643 }
2644
2645 /*
2646  * Check quota settings consistency.
2647  */
2648 static int ext4_check_quota_consistency(struct fs_context *fc,
2649                                         struct super_block *sb)
2650 {
2651 #ifdef CONFIG_QUOTA
2652         struct ext4_fs_context *ctx = fc->fs_private;
2653         struct ext4_sb_info *sbi = EXT4_SB(sb);
2654         bool quota_feature = ext4_has_feature_quota(sb);
2655         bool quota_loaded = sb_any_quota_loaded(sb);
2656         bool usr_qf_name, grp_qf_name, usrquota, grpquota;
2657         int quota_flags, i;
2658
2659         /*
2660          * We do the test below only for project quotas. 'usrquota' and
2661          * 'grpquota' mount options are allowed even without quota feature
2662          * to support legacy quotas in quota files.
2663          */
2664         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_PRJQUOTA) &&
2665             !ext4_has_feature_project(sb)) {
2666                 ext4_msg(NULL, KERN_ERR, "Project quota feature not enabled. "
2667                          "Cannot enable project quota enforcement.");
2668                 return -EINVAL;
2669         }
2670
2671         quota_flags = EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2672                       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA;
2673         if (quota_loaded &&
2674             ctx->mask_s_mount_opt & quota_flags &&
2675             !ctx_test_mount_opt(ctx, quota_flags))
2676                 goto err_quota_change;
2677
2678         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2679
2680                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2681                         if (!(ctx->qname_spec & (1 << i)))
2682                                 continue;
2683
2684                         if (quota_loaded &&
2685                             !!sbi->s_qf_names[i] != !!ctx->s_qf_names[i])
2686                                 goto err_jquota_change;
2687
2688                         if (sbi->s_qf_names[i] && ctx->s_qf_names[i] &&
2689                             strcmp(get_qf_name(sb, sbi, i),
2690                                    ctx->s_qf_names[i]) != 0)
2691                                 goto err_jquota_specified;
2692                 }
2693
2694                 if (quota_feature) {
2695                         ext4_msg(NULL, KERN_INFO,
2696                                  "Journaled quota options ignored when "
2697                                  "QUOTA feature is enabled");
2698                         return 0;
2699                 }
2700         }
2701
2702         if (ctx->spec & EXT4_SPEC_JQFMT) {
2703                 if (sbi->s_jquota_fmt != ctx->s_jquota_fmt && quota_loaded)
2704                         goto err_jquota_change;
2705                 if (quota_feature) {
2706                         ext4_msg(NULL, KERN_INFO, "Quota format mount options "
2707                                  "ignored when QUOTA feature is enabled");
2708                         return 0;
2709                 }
2710         }
2711
2712         /* Make sure we don't mix old and new quota format */
2713         usr_qf_name = (get_qf_name(sb, sbi, USRQUOTA) ||
2714                        ctx->s_qf_names[USRQUOTA]);
2715         grp_qf_name = (get_qf_name(sb, sbi, GRPQUOTA) ||
2716                        ctx->s_qf_names[GRPQUOTA]);
2717
2718         usrquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2719                     test_opt(sb, USRQUOTA));
2720
2721         grpquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) ||
2722                     test_opt(sb, GRPQUOTA));
2723
2724         if (usr_qf_name) {
2725                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2726                 usrquota = false;
2727         }
2728         if (grp_qf_name) {
2729                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2730                 grpquota = false;
2731         }
2732
2733         if (usr_qf_name || grp_qf_name) {
2734                 if (usrquota || grpquota) {
2735                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2736                                  "format mixing");
2737                         return -EINVAL;
2738                 }
2739
2740                 if (!(ctx->spec & EXT4_SPEC_JQFMT || sbi->s_jquota_fmt)) {
2741                         ext4_msg(NULL, KERN_ERR, "journaled quota format "
2742                                  "not specified");
2743                         return -EINVAL;
2744                 }
2745         }
2746
2747         return 0;
2748
2749 err_quota_change:
2750         ext4_msg(NULL, KERN_ERR,
2751                  "Cannot change quota options when quota turned on");
2752         return -EINVAL;
2753 err_jquota_change:
2754         ext4_msg(NULL, KERN_ERR, "Cannot change journaled quota "
2755                  "options when quota turned on");
2756         return -EINVAL;
2757 err_jquota_specified:
2758         ext4_msg(NULL, KERN_ERR, "%s quota file already specified",
2759                  QTYPE2NAME(i));
2760         return -EINVAL;
2761 #else
2762         return 0;
2763 #endif
2764 }
2765
2766 static int ext4_check_opt_consistency(struct fs_context *fc,
2767                                       struct super_block *sb)
2768 {
2769         struct ext4_fs_context *ctx = fc->fs_private;
2770         struct ext4_sb_info *sbi = fc->s_fs_info;
2771         int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2772
2773         if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2774                 ext4_msg(NULL, KERN_ERR,
2775                          "Mount option(s) incompatible with ext2");
2776                 return -EINVAL;
2777         }
2778         if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2779                 ext4_msg(NULL, KERN_ERR,
2780                          "Mount option(s) incompatible with ext3");
2781                 return -EINVAL;
2782         }
2783
2784         if (ctx->s_want_extra_isize >
2785             (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2786                 ext4_msg(NULL, KERN_ERR,
2787                          "Invalid want_extra_isize %d",
2788                          ctx->s_want_extra_isize);
2789                 return -EINVAL;
2790         }
2791
2792         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DIOREAD_NOLOCK)) {
2793                 int blocksize =
2794                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2795                 if (blocksize < PAGE_SIZE)
2796                         ext4_msg(NULL, KERN_WARNING, "Warning: mounting with an "
2797                                  "experimental mount option 'dioread_nolock' "
2798                                  "for blocksize < PAGE_SIZE");
2799         }
2800
2801 #ifdef CONFIG_FS_ENCRYPTION
2802         /*
2803          * This mount option is just for testing, and it's not worthwhile to
2804          * implement the extra complexity (e.g. RCU protection) that would be
2805          * needed to allow it to be set or changed during remount.  We do allow
2806          * it to be specified during remount, but only if there is no change.
2807          */
2808         if ((ctx->spec & EXT4_SPEC_DUMMY_ENCRYPTION) &&
2809             is_remount && !sbi->s_dummy_enc_policy.policy) {
2810                 ext4_msg(NULL, KERN_WARNING,
2811                          "Can't set test_dummy_encryption on remount");
2812                 return -1;
2813         }
2814 #endif
2815
2816         if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2817                 if (!sbi->s_journal) {
2818                         ext4_msg(NULL, KERN_WARNING,
2819                                  "Remounting file system with no journal "
2820                                  "so ignoring journalled data option");
2821                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2822                 } else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2823                            test_opt(sb, DATA_FLAGS)) {
2824                         ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2825                                  "on remount");
2826                         return -EINVAL;
2827                 }
2828         }
2829
2830         if (is_remount) {
2831                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2832                     (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2833                         ext4_msg(NULL, KERN_ERR, "can't mount with "
2834                                  "both data=journal and dax");
2835                         return -EINVAL;
2836                 }
2837
2838                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2839                     (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2840                      (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2841 fail_dax_change_remount:
2842                         ext4_msg(NULL, KERN_ERR, "can't change "
2843                                  "dax mount option while remounting");
2844                         return -EINVAL;
2845                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2846                          (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2847                           (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2848                         goto fail_dax_change_remount;
2849                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2850                            ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2851                             (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2852                             !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2853                         goto fail_dax_change_remount;
2854                 }
2855         }
2856
2857         return ext4_check_quota_consistency(fc, sb);
2858 }
2859
2860 static int ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2861 {
2862         struct ext4_fs_context *ctx = fc->fs_private;
2863         struct ext4_sb_info *sbi = fc->s_fs_info;
2864         int ret = 0;
2865
2866         sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2867         sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2868         sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2869         sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2870         sbi->s_mount_flags &= ~ctx->mask_s_mount_flags;
2871         sbi->s_mount_flags |= ctx->vals_s_mount_flags;
2872         sb->s_flags &= ~ctx->mask_s_flags;
2873         sb->s_flags |= ctx->vals_s_flags;
2874
2875         /*
2876          * i_version differs from common mount option iversion so we have
2877          * to let vfs know that it was set, otherwise it would get cleared
2878          * on remount
2879          */
2880         if (ctx->mask_s_flags & SB_I_VERSION)
2881                 fc->sb_flags |= SB_I_VERSION;
2882
2883 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2884         APPLY(s_commit_interval);
2885         APPLY(s_stripe);
2886         APPLY(s_max_batch_time);
2887         APPLY(s_min_batch_time);
2888         APPLY(s_want_extra_isize);
2889         APPLY(s_inode_readahead_blks);
2890         APPLY(s_max_dir_size_kb);
2891         APPLY(s_li_wait_mult);
2892         APPLY(s_resgid);
2893         APPLY(s_resuid);
2894
2895 #ifdef CONFIG_EXT4_DEBUG
2896         APPLY(s_fc_debug_max_replay);
2897 #endif
2898
2899         ext4_apply_quota_options(fc, sb);
2900
2901         if (ctx->spec & EXT4_SPEC_DUMMY_ENCRYPTION)
2902                 ret = ext4_set_test_dummy_encryption(sb, ctx->test_dummy_enc_arg);
2903
2904         return ret;
2905 }
2906
2907
2908 static int ext4_validate_options(struct fs_context *fc)
2909 {
2910 #ifdef CONFIG_QUOTA
2911         struct ext4_fs_context *ctx = fc->fs_private;
2912         char *usr_qf_name, *grp_qf_name;
2913
2914         usr_qf_name = ctx->s_qf_names[USRQUOTA];
2915         grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2916
2917         if (usr_qf_name || grp_qf_name) {
2918                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2919                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2920
2921                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2922                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2923
2924                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2925                     ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2926                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2927                                  "format mixing");
2928                         return -EINVAL;
2929                 }
2930         }
2931 #endif
2932         return 1;
2933 }
2934
2935 static inline void ext4_show_quota_options(struct seq_file *seq,
2936                                            struct super_block *sb)
2937 {
2938 #if defined(CONFIG_QUOTA)
2939         struct ext4_sb_info *sbi = EXT4_SB(sb);
2940         char *usr_qf_name, *grp_qf_name;
2941
2942         if (sbi->s_jquota_fmt) {
2943                 char *fmtname = "";
2944
2945                 switch (sbi->s_jquota_fmt) {
2946                 case QFMT_VFS_OLD:
2947                         fmtname = "vfsold";
2948                         break;
2949                 case QFMT_VFS_V0:
2950                         fmtname = "vfsv0";
2951                         break;
2952                 case QFMT_VFS_V1:
2953                         fmtname = "vfsv1";
2954                         break;
2955                 }
2956                 seq_printf(seq, ",jqfmt=%s", fmtname);
2957         }
2958
2959         rcu_read_lock();
2960         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2961         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2962         if (usr_qf_name)
2963                 seq_show_option(seq, "usrjquota", usr_qf_name);
2964         if (grp_qf_name)
2965                 seq_show_option(seq, "grpjquota", grp_qf_name);
2966         rcu_read_unlock();
2967 #endif
2968 }
2969
2970 static const char *token2str(int token)
2971 {
2972         const struct fs_parameter_spec *spec;
2973
2974         for (spec = ext4_param_specs; spec->name != NULL; spec++)
2975                 if (spec->opt == token && !spec->type)
2976                         break;
2977         return spec->name;
2978 }
2979
2980 /*
2981  * Show an option if
2982  *  - it's set to a non-default value OR
2983  *  - if the per-sb default is different from the global default
2984  */
2985 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2986                               int nodefs)
2987 {
2988         struct ext4_sb_info *sbi = EXT4_SB(sb);
2989         struct ext4_super_block *es = sbi->s_es;
2990         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2991         const struct mount_opts *m;
2992         char sep = nodefs ? '\n' : ',';
2993
2994 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2995 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2996
2997         if (sbi->s_sb_block != 1)
2998                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2999
3000         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
3001                 int want_set = m->flags & MOPT_SET;
3002                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
3003                     m->flags & MOPT_SKIP)
3004                         continue;
3005                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
3006                         continue; /* skip if same as the default */
3007                 if ((want_set &&
3008                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
3009                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
3010                         continue; /* select Opt_noFoo vs Opt_Foo */
3011                 SEQ_OPTS_PRINT("%s", token2str(m->token));
3012         }
3013
3014         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
3015             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
3016                 SEQ_OPTS_PRINT("resuid=%u",
3017                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
3018         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
3019             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
3020                 SEQ_OPTS_PRINT("resgid=%u",
3021                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
3022         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
3023         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
3024                 SEQ_OPTS_PUTS("errors=remount-ro");
3025         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
3026                 SEQ_OPTS_PUTS("errors=continue");
3027         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
3028                 SEQ_OPTS_PUTS("errors=panic");
3029         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
3030                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
3031         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
3032                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
3033         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
3034                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
3035         if (sb->s_flags & SB_I_VERSION)
3036                 SEQ_OPTS_PUTS("i_version");
3037         if (nodefs || sbi->s_stripe)
3038                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
3039         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
3040                         (sbi->s_mount_opt ^ def_mount_opt)) {
3041                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3042                         SEQ_OPTS_PUTS("data=journal");
3043                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3044                         SEQ_OPTS_PUTS("data=ordered");
3045                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
3046                         SEQ_OPTS_PUTS("data=writeback");
3047         }
3048         if (nodefs ||
3049             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
3050                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
3051                                sbi->s_inode_readahead_blks);
3052
3053         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
3054                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
3055                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
3056         if (nodefs || sbi->s_max_dir_size_kb)
3057                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
3058         if (test_opt(sb, DATA_ERR_ABORT))
3059                 SEQ_OPTS_PUTS("data_err=abort");
3060
3061         fscrypt_show_test_dummy_encryption(seq, sep, sb);
3062
3063         if (sb->s_flags & SB_INLINECRYPT)
3064                 SEQ_OPTS_PUTS("inlinecrypt");
3065
3066         if (test_opt(sb, DAX_ALWAYS)) {
3067                 if (IS_EXT2_SB(sb))
3068                         SEQ_OPTS_PUTS("dax");
3069                 else
3070                         SEQ_OPTS_PUTS("dax=always");
3071         } else if (test_opt2(sb, DAX_NEVER)) {
3072                 SEQ_OPTS_PUTS("dax=never");
3073         } else if (test_opt2(sb, DAX_INODE)) {
3074                 SEQ_OPTS_PUTS("dax=inode");
3075         }
3076         ext4_show_quota_options(seq, sb);
3077         return 0;
3078 }
3079
3080 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
3081 {
3082         return _ext4_show_options(seq, root->d_sb, 0);
3083 }
3084
3085 int ext4_seq_options_show(struct seq_file *seq, void *offset)
3086 {
3087         struct super_block *sb = seq->private;
3088         int rc;
3089
3090         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
3091         rc = _ext4_show_options(seq, sb, 1);
3092         seq_puts(seq, "\n");
3093         return rc;
3094 }
3095
3096 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3097                             int read_only)
3098 {
3099         struct ext4_sb_info *sbi = EXT4_SB(sb);
3100         int err = 0;
3101
3102         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3103                 ext4_msg(sb, KERN_ERR, "revision level too high, "
3104                          "forcing read-only mode");
3105                 err = -EROFS;
3106                 goto done;
3107         }
3108         if (read_only)
3109                 goto done;
3110         if (!(sbi->s_mount_state & EXT4_VALID_FS))
3111                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3112                          "running e2fsck is recommended");
3113         else if (sbi->s_mount_state & EXT4_ERROR_FS)
3114                 ext4_msg(sb, KERN_WARNING,
3115                          "warning: mounting fs with errors, "
3116                          "running e2fsck is recommended");
3117         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3118                  le16_to_cpu(es->s_mnt_count) >=
3119                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3120                 ext4_msg(sb, KERN_WARNING,
3121                          "warning: maximal mount count reached, "
3122                          "running e2fsck is recommended");
3123         else if (le32_to_cpu(es->s_checkinterval) &&
3124                  (ext4_get_tstamp(es, s_lastcheck) +
3125                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3126                 ext4_msg(sb, KERN_WARNING,
3127                          "warning: checktime reached, "
3128                          "running e2fsck is recommended");
3129         if (!sbi->s_journal)
3130                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3131         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3132                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3133         le16_add_cpu(&es->s_mnt_count, 1);
3134         ext4_update_tstamp(es, s_mtime);
3135         if (sbi->s_journal) {
3136                 ext4_set_feature_journal_needs_recovery(sb);
3137                 if (ext4_has_feature_orphan_file(sb))
3138                         ext4_set_feature_orphan_present(sb);
3139         }
3140
3141         err = ext4_commit_super(sb);
3142 done:
3143         if (test_opt(sb, DEBUG))
3144                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3145                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3146                         sb->s_blocksize,
3147                         sbi->s_groups_count,
3148                         EXT4_BLOCKS_PER_GROUP(sb),
3149                         EXT4_INODES_PER_GROUP(sb),
3150                         sbi->s_mount_opt, sbi->s_mount_opt2);
3151         return err;
3152 }
3153
3154 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3155 {
3156         struct ext4_sb_info *sbi = EXT4_SB(sb);
3157         struct flex_groups **old_groups, **new_groups;
3158         int size, i, j;
3159
3160         if (!sbi->s_log_groups_per_flex)
3161                 return 0;
3162
3163         size = ext4_flex_group(sbi, ngroup - 1) + 1;
3164         if (size <= sbi->s_flex_groups_allocated)
3165                 return 0;
3166
3167         new_groups = kvzalloc(roundup_pow_of_two(size *
3168                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3169         if (!new_groups) {
3170                 ext4_msg(sb, KERN_ERR,
3171                          "not enough memory for %d flex group pointers", size);
3172                 return -ENOMEM;
3173         }
3174         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3175                 new_groups[i] = kvzalloc(roundup_pow_of_two(
3176                                          sizeof(struct flex_groups)),
3177                                          GFP_KERNEL);
3178                 if (!new_groups[i]) {
3179                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
3180                                 kvfree(new_groups[j]);
3181                         kvfree(new_groups);
3182                         ext4_msg(sb, KERN_ERR,
3183                                  "not enough memory for %d flex groups", size);
3184                         return -ENOMEM;
3185                 }
3186         }
3187         rcu_read_lock();
3188         old_groups = rcu_dereference(sbi->s_flex_groups);
3189         if (old_groups)
3190                 memcpy(new_groups, old_groups,
3191                        (sbi->s_flex_groups_allocated *
3192                         sizeof(struct flex_groups *)));
3193         rcu_read_unlock();
3194         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3195         sbi->s_flex_groups_allocated = size;
3196         if (old_groups)
3197                 ext4_kvfree_array_rcu(old_groups);
3198         return 0;
3199 }
3200
3201 static int ext4_fill_flex_info(struct super_block *sb)
3202 {
3203         struct ext4_sb_info *sbi = EXT4_SB(sb);
3204         struct ext4_group_desc *gdp = NULL;
3205         struct flex_groups *fg;
3206         ext4_group_t flex_group;
3207         int i, err;
3208
3209         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3210         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3211                 sbi->s_log_groups_per_flex = 0;
3212                 return 1;
3213         }
3214
3215         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3216         if (err)
3217                 goto failed;
3218
3219         for (i = 0; i < sbi->s_groups_count; i++) {
3220                 gdp = ext4_get_group_desc(sb, i, NULL);
3221
3222                 flex_group = ext4_flex_group(sbi, i);
3223                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3224                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3225                 atomic64_add(ext4_free_group_clusters(sb, gdp),
3226                              &fg->free_clusters);
3227                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3228         }
3229
3230         return 1;
3231 failed:
3232         return 0;
3233 }
3234
3235 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3236                                    struct ext4_group_desc *gdp)
3237 {
3238         int offset = offsetof(struct ext4_group_desc, bg_checksum);
3239         __u16 crc = 0;
3240         __le32 le_group = cpu_to_le32(block_group);
3241         struct ext4_sb_info *sbi = EXT4_SB(sb);
3242
3243         if (ext4_has_metadata_csum(sbi->s_sb)) {
3244                 /* Use new metadata_csum algorithm */
3245                 __u32 csum32;
3246                 __u16 dummy_csum = 0;
3247
3248                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
3249                                      sizeof(le_group));
3250                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
3251                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
3252                                      sizeof(dummy_csum));
3253                 offset += sizeof(dummy_csum);
3254                 if (offset < sbi->s_desc_size)
3255                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
3256                                              sbi->s_desc_size - offset);
3257
3258                 crc = csum32 & 0xFFFF;
3259                 goto out;
3260         }
3261
3262         /* old crc16 code */
3263         if (!ext4_has_feature_gdt_csum(sb))
3264                 return 0;
3265
3266         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3267         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3268         crc = crc16(crc, (__u8 *)gdp, offset);
3269         offset += sizeof(gdp->bg_checksum); /* skip checksum */
3270         /* for checksum of struct ext4_group_desc do the rest...*/
3271         if (ext4_has_feature_64bit(sb) &&
3272             offset < le16_to_cpu(sbi->s_es->s_desc_size))
3273                 crc = crc16(crc, (__u8 *)gdp + offset,
3274                             le16_to_cpu(sbi->s_es->s_desc_size) -
3275                                 offset);
3276
3277 out:
3278         return cpu_to_le16(crc);
3279 }
3280
3281 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3282                                 struct ext4_group_desc *gdp)
3283 {
3284         if (ext4_has_group_desc_csum(sb) &&
3285             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3286                 return 0;
3287
3288         return 1;
3289 }
3290
3291 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3292                               struct ext4_group_desc *gdp)
3293 {
3294         if (!ext4_has_group_desc_csum(sb))
3295                 return;
3296         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3297 }
3298
3299 /* Called at mount-time, super-block is locked */
3300 static int ext4_check_descriptors(struct super_block *sb,
3301                                   ext4_fsblk_t sb_block,
3302                                   ext4_group_t *first_not_zeroed)
3303 {
3304         struct ext4_sb_info *sbi = EXT4_SB(sb);
3305         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3306         ext4_fsblk_t last_block;
3307         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3308         ext4_fsblk_t block_bitmap;
3309         ext4_fsblk_t inode_bitmap;
3310         ext4_fsblk_t inode_table;
3311         int flexbg_flag = 0;
3312         ext4_group_t i, grp = sbi->s_groups_count;
3313
3314         if (ext4_has_feature_flex_bg(sb))
3315                 flexbg_flag = 1;
3316
3317         ext4_debug("Checking group descriptors");
3318
3319         for (i = 0; i < sbi->s_groups_count; i++) {
3320                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3321
3322                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
3323                         last_block = ext4_blocks_count(sbi->s_es) - 1;
3324                 else
3325                         last_block = first_block +
3326                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
3327
3328                 if ((grp == sbi->s_groups_count) &&
3329                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3330                         grp = i;
3331
3332                 block_bitmap = ext4_block_bitmap(sb, gdp);
3333                 if (block_bitmap == sb_block) {
3334                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3335                                  "Block bitmap for group %u overlaps "
3336                                  "superblock", i);
3337                         if (!sb_rdonly(sb))
3338                                 return 0;
3339                 }
3340                 if (block_bitmap >= sb_block + 1 &&
3341                     block_bitmap <= last_bg_block) {
3342                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3343                                  "Block bitmap for group %u overlaps "
3344                                  "block group descriptors", i);
3345                         if (!sb_rdonly(sb))
3346                                 return 0;
3347                 }
3348                 if (block_bitmap < first_block || block_bitmap > last_block) {
3349                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3350                                "Block bitmap for group %u not in group "
3351                                "(block %llu)!", i, block_bitmap);
3352                         return 0;
3353                 }
3354                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
3355                 if (inode_bitmap == sb_block) {
3356                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3357                                  "Inode bitmap for group %u overlaps "
3358                                  "superblock", i);
3359                         if (!sb_rdonly(sb))
3360                                 return 0;
3361                 }
3362                 if (inode_bitmap >= sb_block + 1 &&
3363                     inode_bitmap <= last_bg_block) {
3364                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3365                                  "Inode bitmap for group %u overlaps "
3366                                  "block group descriptors", i);
3367                         if (!sb_rdonly(sb))
3368                                 return 0;
3369                 }
3370                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
3371                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3372                                "Inode bitmap for group %u not in group "
3373                                "(block %llu)!", i, inode_bitmap);
3374                         return 0;
3375                 }
3376                 inode_table = ext4_inode_table(sb, gdp);
3377                 if (inode_table == sb_block) {
3378                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3379                                  "Inode table for group %u overlaps "
3380                                  "superblock", i);
3381                         if (!sb_rdonly(sb))
3382                                 return 0;
3383                 }
3384                 if (inode_table >= sb_block + 1 &&
3385                     inode_table <= last_bg_block) {
3386                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3387                                  "Inode table for group %u overlaps "
3388                                  "block group descriptors", i);
3389                         if (!sb_rdonly(sb))
3390                                 return 0;
3391                 }
3392                 if (inode_table < first_block ||
3393                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
3394                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3395                                "Inode table for group %u not in group "
3396                                "(block %llu)!", i, inode_table);
3397                         return 0;
3398                 }
3399                 ext4_lock_group(sb, i);
3400                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3401                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3402                                  "Checksum for group %u failed (%u!=%u)",
3403                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3404                                      gdp)), le16_to_cpu(gdp->bg_checksum));
3405                         if (!sb_rdonly(sb)) {
3406                                 ext4_unlock_group(sb, i);
3407                                 return 0;
3408                         }
3409                 }
3410                 ext4_unlock_group(sb, i);
3411                 if (!flexbg_flag)
3412                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
3413         }
3414         if (NULL != first_not_zeroed)
3415                 *first_not_zeroed = grp;
3416         return 1;
3417 }
3418
3419 /*
3420  * Maximal extent format file size.
3421  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3422  * extent format containers, within a sector_t, and within i_blocks
3423  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3424  * so that won't be a limiting factor.
3425  *
3426  * However there is other limiting factor. We do store extents in the form
3427  * of starting block and length, hence the resulting length of the extent
3428  * covering maximum file size must fit into on-disk format containers as
3429  * well. Given that length is always by 1 unit bigger than max unit (because
3430  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3431  *
3432  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3433  */
3434 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3435 {
3436         loff_t res;
3437         loff_t upper_limit = MAX_LFS_FILESIZE;
3438
3439         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3440
3441         if (!has_huge_files) {
3442                 upper_limit = (1LL << 32) - 1;
3443
3444                 /* total blocks in file system block size */
3445                 upper_limit >>= (blkbits - 9);
3446                 upper_limit <<= blkbits;
3447         }
3448
3449         /*
3450          * 32-bit extent-start container, ee_block. We lower the maxbytes
3451          * by one fs block, so ee_len can cover the extent of maximum file
3452          * size
3453          */
3454         res = (1LL << 32) - 1;
3455         res <<= blkbits;
3456
3457         /* Sanity check against vm- & vfs- imposed limits */
3458         if (res > upper_limit)
3459                 res = upper_limit;
3460
3461         return res;
3462 }
3463
3464 /*
3465  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3466  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3467  * We need to be 1 filesystem block less than the 2^48 sector limit.
3468  */
3469 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3470 {
3471         unsigned long long upper_limit, res = EXT4_NDIR_BLOCKS;
3472         int meta_blocks;
3473
3474         /*
3475          * This is calculated to be the largest file size for a dense, block
3476          * mapped file such that the file's total number of 512-byte sectors,
3477          * including data and all indirect blocks, does not exceed (2^48 - 1).
3478          *
3479          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3480          * number of 512-byte sectors of the file.
3481          */
3482         if (!has_huge_files) {
3483                 /*
3484                  * !has_huge_files or implies that the inode i_block field
3485                  * represents total file blocks in 2^32 512-byte sectors ==
3486                  * size of vfs inode i_blocks * 8
3487                  */
3488                 upper_limit = (1LL << 32) - 1;
3489
3490                 /* total blocks in file system block size */
3491                 upper_limit >>= (bits - 9);
3492
3493         } else {
3494                 /*
3495                  * We use 48 bit ext4_inode i_blocks
3496                  * With EXT4_HUGE_FILE_FL set the i_blocks
3497                  * represent total number of blocks in
3498                  * file system block size
3499                  */
3500                 upper_limit = (1LL << 48) - 1;
3501
3502         }
3503
3504         /* indirect blocks */
3505         meta_blocks = 1;
3506         /* double indirect blocks */
3507         meta_blocks += 1 + (1LL << (bits-2));
3508         /* tripple indirect blocks */
3509         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3510
3511         upper_limit -= meta_blocks;
3512         upper_limit <<= bits;
3513
3514         res += 1LL << (bits-2);
3515         res += 1LL << (2*(bits-2));
3516         res += 1LL << (3*(bits-2));
3517         res <<= bits;
3518         if (res > upper_limit)
3519                 res = upper_limit;
3520
3521         if (res > MAX_LFS_FILESIZE)
3522                 res = MAX_LFS_FILESIZE;
3523
3524         return (loff_t)res;
3525 }
3526
3527 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3528                                    ext4_fsblk_t logical_sb_block, int nr)
3529 {
3530         struct ext4_sb_info *sbi = EXT4_SB(sb);
3531         ext4_group_t bg, first_meta_bg;
3532         int has_super = 0;
3533
3534         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3535
3536         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3537                 return logical_sb_block + nr + 1;
3538         bg = sbi->s_desc_per_block * nr;
3539         if (ext4_bg_has_super(sb, bg))
3540                 has_super = 1;
3541
3542         /*
3543          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3544          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3545          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3546          * compensate.
3547          */
3548         if (sb->s_blocksize == 1024 && nr == 0 &&
3549             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3550                 has_super++;
3551
3552         return (has_super + ext4_group_first_block_no(sb, bg));
3553 }
3554
3555 /**
3556  * ext4_get_stripe_size: Get the stripe size.
3557  * @sbi: In memory super block info
3558  *
3559  * If we have specified it via mount option, then
3560  * use the mount option value. If the value specified at mount time is
3561  * greater than the blocks per group use the super block value.
3562  * If the super block value is greater than blocks per group return 0.
3563  * Allocator needs it be less than blocks per group.
3564  *
3565  */
3566 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3567 {
3568         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3569         unsigned long stripe_width =
3570                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3571         int ret;
3572
3573         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3574                 ret = sbi->s_stripe;
3575         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3576                 ret = stripe_width;
3577         else if (stride && stride <= sbi->s_blocks_per_group)
3578                 ret = stride;
3579         else
3580                 ret = 0;
3581
3582         /*
3583          * If the stripe width is 1, this makes no sense and
3584          * we set it to 0 to turn off stripe handling code.
3585          */
3586         if (ret <= 1)
3587                 ret = 0;
3588
3589         return ret;
3590 }
3591
3592 /*
3593  * Check whether this filesystem can be mounted based on
3594  * the features present and the RDONLY/RDWR mount requested.
3595  * Returns 1 if this filesystem can be mounted as requested,
3596  * 0 if it cannot be.
3597  */
3598 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3599 {
3600         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3601                 ext4_msg(sb, KERN_ERR,
3602                         "Couldn't mount because of "
3603                         "unsupported optional features (%x)",
3604                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3605                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3606                 return 0;
3607         }
3608
3609 #ifndef CONFIG_UNICODE
3610         if (ext4_has_feature_casefold(sb)) {
3611                 ext4_msg(sb, KERN_ERR,
3612                          "Filesystem with casefold feature cannot be "
3613                          "mounted without CONFIG_UNICODE");
3614                 return 0;
3615         }
3616 #endif
3617
3618         if (readonly)
3619                 return 1;
3620
3621         if (ext4_has_feature_readonly(sb)) {
3622                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3623                 sb->s_flags |= SB_RDONLY;
3624                 return 1;
3625         }
3626
3627         /* Check that feature set is OK for a read-write mount */
3628         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3629                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3630                          "unsupported optional features (%x)",
3631                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3632                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3633                 return 0;
3634         }
3635         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3636                 ext4_msg(sb, KERN_ERR,
3637                          "Can't support bigalloc feature without "
3638                          "extents feature\n");
3639                 return 0;
3640         }
3641
3642 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3643         if (!readonly && (ext4_has_feature_quota(sb) ||
3644                           ext4_has_feature_project(sb))) {
3645                 ext4_msg(sb, KERN_ERR,
3646                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3647                 return 0;
3648         }
3649 #endif  /* CONFIG_QUOTA */
3650         return 1;
3651 }
3652
3653 /*
3654  * This function is called once a day if we have errors logged
3655  * on the file system
3656  */
3657 static void print_daily_error_info(struct timer_list *t)
3658 {
3659         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3660         struct super_block *sb = sbi->s_sb;
3661         struct ext4_super_block *es = sbi->s_es;
3662
3663         if (es->s_error_count)
3664                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3665                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3666                          le32_to_cpu(es->s_error_count));
3667         if (es->s_first_error_time) {
3668                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3669                        sb->s_id,
3670                        ext4_get_tstamp(es, s_first_error_time),
3671                        (int) sizeof(es->s_first_error_func),
3672                        es->s_first_error_func,
3673                        le32_to_cpu(es->s_first_error_line));
3674                 if (es->s_first_error_ino)
3675                         printk(KERN_CONT ": inode %u",
3676                                le32_to_cpu(es->s_first_error_ino));
3677                 if (es->s_first_error_block)
3678                         printk(KERN_CONT ": block %llu", (unsigned long long)
3679                                le64_to_cpu(es->s_first_error_block));
3680                 printk(KERN_CONT "\n");
3681         }
3682         if (es->s_last_error_time) {
3683                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3684                        sb->s_id,
3685                        ext4_get_tstamp(es, s_last_error_time),
3686                        (int) sizeof(es->s_last_error_func),
3687                        es->s_last_error_func,
3688                        le32_to_cpu(es->s_last_error_line));
3689                 if (es->s_last_error_ino)
3690                         printk(KERN_CONT ": inode %u",
3691                                le32_to_cpu(es->s_last_error_ino));
3692                 if (es->s_last_error_block)
3693                         printk(KERN_CONT ": block %llu", (unsigned long long)
3694                                le64_to_cpu(es->s_last_error_block));
3695                 printk(KERN_CONT "\n");
3696         }
3697         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3698 }
3699
3700 /* Find next suitable group and run ext4_init_inode_table */
3701 static int ext4_run_li_request(struct ext4_li_request *elr)
3702 {
3703         struct ext4_group_desc *gdp = NULL;
3704         struct super_block *sb = elr->lr_super;
3705         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3706         ext4_group_t group = elr->lr_next_group;
3707         unsigned int prefetch_ios = 0;
3708         int ret = 0;
3709         u64 start_time;
3710
3711         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3712                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3713                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3714                 if (prefetch_ios)
3715                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3716                                               prefetch_ios);
3717                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3718                                             prefetch_ios);
3719                 if (group >= elr->lr_next_group) {
3720                         ret = 1;
3721                         if (elr->lr_first_not_zeroed != ngroups &&
3722                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3723                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3724                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3725                                 ret = 0;
3726                         }
3727                 }
3728                 return ret;
3729         }
3730
3731         for (; group < ngroups; group++) {
3732                 gdp = ext4_get_group_desc(sb, group, NULL);
3733                 if (!gdp) {
3734                         ret = 1;
3735                         break;
3736                 }
3737
3738                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3739                         break;
3740         }
3741
3742         if (group >= ngroups)
3743                 ret = 1;
3744
3745         if (!ret) {
3746                 start_time = ktime_get_real_ns();
3747                 ret = ext4_init_inode_table(sb, group,
3748                                             elr->lr_timeout ? 0 : 1);
3749                 trace_ext4_lazy_itable_init(sb, group);
3750                 if (elr->lr_timeout == 0) {
3751                         elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3752                                 EXT4_SB(elr->lr_super)->s_li_wait_mult);
3753                 }
3754                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3755                 elr->lr_next_group = group + 1;
3756         }
3757         return ret;
3758 }
3759
3760 /*
3761  * Remove lr_request from the list_request and free the
3762  * request structure. Should be called with li_list_mtx held
3763  */
3764 static void ext4_remove_li_request(struct ext4_li_request *elr)
3765 {
3766         if (!elr)
3767                 return;
3768
3769         list_del(&elr->lr_request);
3770         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3771         kfree(elr);
3772 }
3773
3774 static void ext4_unregister_li_request(struct super_block *sb)
3775 {
3776         mutex_lock(&ext4_li_mtx);
3777         if (!ext4_li_info) {
3778                 mutex_unlock(&ext4_li_mtx);
3779                 return;
3780         }
3781
3782         mutex_lock(&ext4_li_info->li_list_mtx);
3783         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3784         mutex_unlock(&ext4_li_info->li_list_mtx);
3785         mutex_unlock(&ext4_li_mtx);
3786 }
3787
3788 static struct task_struct *ext4_lazyinit_task;
3789
3790 /*
3791  * This is the function where ext4lazyinit thread lives. It walks
3792  * through the request list searching for next scheduled filesystem.
3793  * When such a fs is found, run the lazy initialization request
3794  * (ext4_rn_li_request) and keep track of the time spend in this
3795  * function. Based on that time we compute next schedule time of
3796  * the request. When walking through the list is complete, compute
3797  * next waking time and put itself into sleep.
3798  */
3799 static int ext4_lazyinit_thread(void *arg)
3800 {
3801         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3802         struct list_head *pos, *n;
3803         struct ext4_li_request *elr;
3804         unsigned long next_wakeup, cur;
3805
3806         BUG_ON(NULL == eli);
3807
3808 cont_thread:
3809         while (true) {
3810                 next_wakeup = MAX_JIFFY_OFFSET;
3811
3812                 mutex_lock(&eli->li_list_mtx);
3813                 if (list_empty(&eli->li_request_list)) {
3814                         mutex_unlock(&eli->li_list_mtx);
3815                         goto exit_thread;
3816                 }
3817                 list_for_each_safe(pos, n, &eli->li_request_list) {
3818                         int err = 0;
3819                         int progress = 0;
3820                         elr = list_entry(pos, struct ext4_li_request,
3821                                          lr_request);
3822
3823                         if (time_before(jiffies, elr->lr_next_sched)) {
3824                                 if (time_before(elr->lr_next_sched, next_wakeup))
3825                                         next_wakeup = elr->lr_next_sched;
3826                                 continue;
3827                         }
3828                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3829                                 if (sb_start_write_trylock(elr->lr_super)) {
3830                                         progress = 1;
3831                                         /*
3832                                          * We hold sb->s_umount, sb can not
3833                                          * be removed from the list, it is
3834                                          * now safe to drop li_list_mtx
3835                                          */
3836                                         mutex_unlock(&eli->li_list_mtx);
3837                                         err = ext4_run_li_request(elr);
3838                                         sb_end_write(elr->lr_super);
3839                                         mutex_lock(&eli->li_list_mtx);
3840                                         n = pos->next;
3841                                 }
3842                                 up_read((&elr->lr_super->s_umount));
3843                         }
3844                         /* error, remove the lazy_init job */
3845                         if (err) {
3846                                 ext4_remove_li_request(elr);
3847                                 continue;
3848                         }
3849                         if (!progress) {
3850                                 elr->lr_next_sched = jiffies +
3851                                         (prandom_u32()
3852                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3853                         }
3854                         if (time_before(elr->lr_next_sched, next_wakeup))
3855                                 next_wakeup = elr->lr_next_sched;
3856                 }
3857                 mutex_unlock(&eli->li_list_mtx);
3858
3859                 try_to_freeze();
3860
3861                 cur = jiffies;
3862                 if ((time_after_eq(cur, next_wakeup)) ||
3863                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3864                         cond_resched();
3865                         continue;
3866                 }
3867
3868                 schedule_timeout_interruptible(next_wakeup - cur);
3869
3870                 if (kthread_should_stop()) {
3871                         ext4_clear_request_list();
3872                         goto exit_thread;
3873                 }
3874         }
3875
3876 exit_thread:
3877         /*
3878          * It looks like the request list is empty, but we need
3879          * to check it under the li_list_mtx lock, to prevent any
3880          * additions into it, and of course we should lock ext4_li_mtx
3881          * to atomically free the list and ext4_li_info, because at
3882          * this point another ext4 filesystem could be registering
3883          * new one.
3884          */
3885         mutex_lock(&ext4_li_mtx);
3886         mutex_lock(&eli->li_list_mtx);
3887         if (!list_empty(&eli->li_request_list)) {
3888                 mutex_unlock(&eli->li_list_mtx);
3889                 mutex_unlock(&ext4_li_mtx);
3890                 goto cont_thread;
3891         }
3892         mutex_unlock(&eli->li_list_mtx);
3893         kfree(ext4_li_info);
3894         ext4_li_info = NULL;
3895         mutex_unlock(&ext4_li_mtx);
3896
3897         return 0;
3898 }
3899
3900 static void ext4_clear_request_list(void)
3901 {
3902         struct list_head *pos, *n;
3903         struct ext4_li_request *elr;
3904
3905         mutex_lock(&ext4_li_info->li_list_mtx);
3906         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3907                 elr = list_entry(pos, struct ext4_li_request,
3908                                  lr_request);
3909                 ext4_remove_li_request(elr);
3910         }
3911         mutex_unlock(&ext4_li_info->li_list_mtx);
3912 }
3913
3914 static int ext4_run_lazyinit_thread(void)
3915 {
3916         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3917                                          ext4_li_info, "ext4lazyinit");
3918         if (IS_ERR(ext4_lazyinit_task)) {
3919                 int err = PTR_ERR(ext4_lazyinit_task);
3920                 ext4_clear_request_list();
3921                 kfree(ext4_li_info);
3922                 ext4_li_info = NULL;
3923                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3924                                  "initialization thread\n",
3925                                  err);
3926                 return err;
3927         }
3928         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3929         return 0;
3930 }
3931
3932 /*
3933  * Check whether it make sense to run itable init. thread or not.
3934  * If there is at least one uninitialized inode table, return
3935  * corresponding group number, else the loop goes through all
3936  * groups and return total number of groups.
3937  */
3938 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3939 {
3940         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3941         struct ext4_group_desc *gdp = NULL;
3942
3943         if (!ext4_has_group_desc_csum(sb))
3944                 return ngroups;
3945
3946         for (group = 0; group < ngroups; group++) {
3947                 gdp = ext4_get_group_desc(sb, group, NULL);
3948                 if (!gdp)
3949                         continue;
3950
3951                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3952                         break;
3953         }
3954
3955         return group;
3956 }
3957
3958 static int ext4_li_info_new(void)
3959 {
3960         struct ext4_lazy_init *eli = NULL;
3961
3962         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3963         if (!eli)
3964                 return -ENOMEM;
3965
3966         INIT_LIST_HEAD(&eli->li_request_list);
3967         mutex_init(&eli->li_list_mtx);
3968
3969         eli->li_state |= EXT4_LAZYINIT_QUIT;
3970
3971         ext4_li_info = eli;
3972
3973         return 0;
3974 }
3975
3976 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3977                                             ext4_group_t start)
3978 {
3979         struct ext4_li_request *elr;
3980
3981         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3982         if (!elr)
3983                 return NULL;
3984
3985         elr->lr_super = sb;
3986         elr->lr_first_not_zeroed = start;
3987         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3988                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3989                 elr->lr_next_group = start;
3990         } else {
3991                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3992         }
3993
3994         /*
3995          * Randomize first schedule time of the request to
3996          * spread the inode table initialization requests
3997          * better.
3998          */
3999         elr->lr_next_sched = jiffies + (prandom_u32() %
4000                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
4001         return elr;
4002 }
4003
4004 int ext4_register_li_request(struct super_block *sb,
4005                              ext4_group_t first_not_zeroed)
4006 {
4007         struct ext4_sb_info *sbi = EXT4_SB(sb);
4008         struct ext4_li_request *elr = NULL;
4009         ext4_group_t ngroups = sbi->s_groups_count;
4010         int ret = 0;
4011
4012         mutex_lock(&ext4_li_mtx);
4013         if (sbi->s_li_request != NULL) {
4014                 /*
4015                  * Reset timeout so it can be computed again, because
4016                  * s_li_wait_mult might have changed.
4017                  */
4018                 sbi->s_li_request->lr_timeout = 0;
4019                 goto out;
4020         }
4021
4022         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
4023             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
4024              !test_opt(sb, INIT_INODE_TABLE)))
4025                 goto out;
4026
4027         elr = ext4_li_request_new(sb, first_not_zeroed);
4028         if (!elr) {
4029                 ret = -ENOMEM;
4030                 goto out;
4031         }
4032
4033         if (NULL == ext4_li_info) {
4034                 ret = ext4_li_info_new();
4035                 if (ret)
4036                         goto out;
4037         }
4038
4039         mutex_lock(&ext4_li_info->li_list_mtx);
4040         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
4041         mutex_unlock(&ext4_li_info->li_list_mtx);
4042
4043         sbi->s_li_request = elr;
4044         /*
4045          * set elr to NULL here since it has been inserted to
4046          * the request_list and the removal and free of it is
4047          * handled by ext4_clear_request_list from now on.
4048          */
4049         elr = NULL;
4050
4051         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
4052                 ret = ext4_run_lazyinit_thread();
4053                 if (ret)
4054                         goto out;
4055         }
4056 out:
4057         mutex_unlock(&ext4_li_mtx);
4058         if (ret)
4059                 kfree(elr);
4060         return ret;
4061 }
4062
4063 /*
4064  * We do not need to lock anything since this is called on
4065  * module unload.
4066  */
4067 static void ext4_destroy_lazyinit_thread(void)
4068 {
4069         /*
4070          * If thread exited earlier
4071          * there's nothing to be done.
4072          */
4073         if (!ext4_li_info || !ext4_lazyinit_task)
4074                 return;
4075
4076         kthread_stop(ext4_lazyinit_task);
4077 }
4078
4079 static int set_journal_csum_feature_set(struct super_block *sb)
4080 {
4081         int ret = 1;
4082         int compat, incompat;
4083         struct ext4_sb_info *sbi = EXT4_SB(sb);
4084
4085         if (ext4_has_metadata_csum(sb)) {
4086                 /* journal checksum v3 */
4087                 compat = 0;
4088                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4089         } else {
4090                 /* journal checksum v1 */
4091                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4092                 incompat = 0;
4093         }
4094
4095         jbd2_journal_clear_features(sbi->s_journal,
4096                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4097                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4098                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
4099         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4100                 ret = jbd2_journal_set_features(sbi->s_journal,
4101                                 compat, 0,
4102                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4103                                 incompat);
4104         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4105                 ret = jbd2_journal_set_features(sbi->s_journal,
4106                                 compat, 0,
4107                                 incompat);
4108                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4109                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4110         } else {
4111                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4112                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4113         }
4114
4115         return ret;
4116 }
4117
4118 /*
4119  * Note: calculating the overhead so we can be compatible with
4120  * historical BSD practice is quite difficult in the face of
4121  * clusters/bigalloc.  This is because multiple metadata blocks from
4122  * different block group can end up in the same allocation cluster.
4123  * Calculating the exact overhead in the face of clustered allocation
4124  * requires either O(all block bitmaps) in memory or O(number of block
4125  * groups**2) in time.  We will still calculate the superblock for
4126  * older file systems --- and if we come across with a bigalloc file
4127  * system with zero in s_overhead_clusters the estimate will be close to
4128  * correct especially for very large cluster sizes --- but for newer
4129  * file systems, it's better to calculate this figure once at mkfs
4130  * time, and store it in the superblock.  If the superblock value is
4131  * present (even for non-bigalloc file systems), we will use it.
4132  */
4133 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4134                           char *buf)
4135 {
4136         struct ext4_sb_info     *sbi = EXT4_SB(sb);
4137         struct ext4_group_desc  *gdp;
4138         ext4_fsblk_t            first_block, last_block, b;
4139         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
4140         int                     s, j, count = 0;
4141
4142         if (!ext4_has_feature_bigalloc(sb))
4143                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
4144                         sbi->s_itb_per_group + 2);
4145
4146         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4147                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
4148         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4149         for (i = 0; i < ngroups; i++) {
4150                 gdp = ext4_get_group_desc(sb, i, NULL);
4151                 b = ext4_block_bitmap(sb, gdp);
4152                 if (b >= first_block && b <= last_block) {
4153                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4154                         count++;
4155                 }
4156                 b = ext4_inode_bitmap(sb, gdp);
4157                 if (b >= first_block && b <= last_block) {
4158                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4159                         count++;
4160                 }
4161                 b = ext4_inode_table(sb, gdp);
4162                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4163                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4164                                 int c = EXT4_B2C(sbi, b - first_block);
4165                                 ext4_set_bit(c, buf);
4166                                 count++;
4167                         }
4168                 if (i != grp)
4169                         continue;
4170                 s = 0;
4171                 if (ext4_bg_has_super(sb, grp)) {
4172                         ext4_set_bit(s++, buf);
4173                         count++;
4174                 }
4175                 j = ext4_bg_num_gdb(sb, grp);
4176                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4177                         ext4_error(sb, "Invalid number of block group "
4178                                    "descriptor blocks: %d", j);
4179                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4180                 }
4181                 count += j;
4182                 for (; j > 0; j--)
4183                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4184         }
4185         if (!count)
4186                 return 0;
4187         return EXT4_CLUSTERS_PER_GROUP(sb) -
4188                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4189 }
4190
4191 /*
4192  * Compute the overhead and stash it in sbi->s_overhead
4193  */
4194 int ext4_calculate_overhead(struct super_block *sb)
4195 {
4196         struct ext4_sb_info *sbi = EXT4_SB(sb);
4197         struct ext4_super_block *es = sbi->s_es;
4198         struct inode *j_inode;
4199         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4200         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4201         ext4_fsblk_t overhead = 0;
4202         char *buf = (char *) get_zeroed_page(GFP_NOFS);
4203
4204         if (!buf)
4205                 return -ENOMEM;
4206
4207         /*
4208          * Compute the overhead (FS structures).  This is constant
4209          * for a given filesystem unless the number of block groups
4210          * changes so we cache the previous value until it does.
4211          */
4212
4213         /*
4214          * All of the blocks before first_data_block are overhead
4215          */
4216         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4217
4218         /*
4219          * Add the overhead found in each block group
4220          */
4221         for (i = 0; i < ngroups; i++) {
4222                 int blks;
4223
4224                 blks = count_overhead(sb, i, buf);
4225                 overhead += blks;
4226                 if (blks)
4227                         memset(buf, 0, PAGE_SIZE);
4228                 cond_resched();
4229         }
4230
4231         /*
4232          * Add the internal journal blocks whether the journal has been
4233          * loaded or not
4234          */
4235         if (sbi->s_journal && !sbi->s_journal_bdev)
4236                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4237         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4238                 /* j_inum for internal journal is non-zero */
4239                 j_inode = ext4_get_journal_inode(sb, j_inum);
4240                 if (j_inode) {
4241                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4242                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
4243                         iput(j_inode);
4244                 } else {
4245                         ext4_msg(sb, KERN_ERR, "can't get journal size");
4246                 }
4247         }
4248         sbi->s_overhead = overhead;
4249         smp_wmb();
4250         free_page((unsigned long) buf);
4251         return 0;
4252 }
4253
4254 static void ext4_set_resv_clusters(struct super_block *sb)
4255 {
4256         ext4_fsblk_t resv_clusters;
4257         struct ext4_sb_info *sbi = EXT4_SB(sb);
4258
4259         /*
4260          * There's no need to reserve anything when we aren't using extents.
4261          * The space estimates are exact, there are no unwritten extents,
4262          * hole punching doesn't need new metadata... This is needed especially
4263          * to keep ext2/3 backward compatibility.
4264          */
4265         if (!ext4_has_feature_extents(sb))
4266                 return;
4267         /*
4268          * By default we reserve 2% or 4096 clusters, whichever is smaller.
4269          * This should cover the situations where we can not afford to run
4270          * out of space like for example punch hole, or converting
4271          * unwritten extents in delalloc path. In most cases such
4272          * allocation would require 1, or 2 blocks, higher numbers are
4273          * very rare.
4274          */
4275         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4276                          sbi->s_cluster_bits);
4277
4278         do_div(resv_clusters, 50);
4279         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4280
4281         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4282 }
4283
4284 static const char *ext4_quota_mode(struct super_block *sb)
4285 {
4286 #ifdef CONFIG_QUOTA
4287         if (!ext4_quota_capable(sb))
4288                 return "none";
4289
4290         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4291                 return "journalled";
4292         else
4293                 return "writeback";
4294 #else
4295         return "disabled";
4296 #endif
4297 }
4298
4299 static void ext4_setup_csum_trigger(struct super_block *sb,
4300                                     enum ext4_journal_trigger_type type,
4301                                     void (*trigger)(
4302                                         struct jbd2_buffer_trigger_type *type,
4303                                         struct buffer_head *bh,
4304                                         void *mapped_data,
4305                                         size_t size))
4306 {
4307         struct ext4_sb_info *sbi = EXT4_SB(sb);
4308
4309         sbi->s_journal_triggers[type].sb = sb;
4310         sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4311 }
4312
4313 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4314 {
4315         if (!sbi)
4316                 return;
4317
4318         kfree(sbi->s_blockgroup_lock);
4319         fs_put_dax(sbi->s_daxdev);
4320         kfree(sbi);
4321 }
4322
4323 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4324 {
4325         struct ext4_sb_info *sbi;
4326
4327         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4328         if (!sbi)
4329                 return NULL;
4330
4331         sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off);
4332
4333         sbi->s_blockgroup_lock =
4334                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4335
4336         if (!sbi->s_blockgroup_lock)
4337                 goto err_out;
4338
4339         sb->s_fs_info = sbi;
4340         sbi->s_sb = sb;
4341         return sbi;
4342 err_out:
4343         fs_put_dax(sbi->s_daxdev);
4344         kfree(sbi);
4345         return NULL;
4346 }
4347
4348 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
4349 {
4350         struct buffer_head *bh, **group_desc;
4351         struct ext4_super_block *es = NULL;
4352         struct ext4_sb_info *sbi = EXT4_SB(sb);
4353         struct flex_groups **flex_groups;
4354         ext4_fsblk_t block;
4355         ext4_fsblk_t logical_sb_block;
4356         unsigned long offset = 0;
4357         unsigned long def_mount_opts;
4358         struct inode *root;
4359         int ret = -ENOMEM;
4360         int blocksize, clustersize;
4361         unsigned int db_count;
4362         unsigned int i;
4363         int needs_recovery, has_huge_files;
4364         __u64 blocks_count;
4365         int err = 0;
4366         ext4_group_t first_not_zeroed;
4367         struct ext4_fs_context *ctx = fc->fs_private;
4368         int silent = fc->sb_flags & SB_SILENT;
4369
4370         /* Set defaults for the variables that will be set during parsing */
4371         ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4372         ctx->mb_optimize_scan = DEFAULT_MB_OPTIMIZE_SCAN;
4373
4374         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
4375         sbi->s_sectors_written_start =
4376                 part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
4377
4378         /* -EINVAL is default */
4379         ret = -EINVAL;
4380         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4381         if (!blocksize) {
4382                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4383                 goto out_fail;
4384         }
4385
4386         /*
4387          * The ext4 superblock will not be buffer aligned for other than 1kB
4388          * block sizes.  We need to calculate the offset from buffer start.
4389          */
4390         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4391                 logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
4392                 offset = do_div(logical_sb_block, blocksize);
4393         } else {
4394                 logical_sb_block = sbi->s_sb_block;
4395         }
4396
4397         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4398         if (IS_ERR(bh)) {
4399                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4400                 ret = PTR_ERR(bh);
4401                 goto out_fail;
4402         }
4403         /*
4404          * Note: s_es must be initialized as soon as possible because
4405          *       some ext4 macro-instructions depend on its value
4406          */
4407         es = (struct ext4_super_block *) (bh->b_data + offset);
4408         sbi->s_es = es;
4409         sb->s_magic = le16_to_cpu(es->s_magic);
4410         if (sb->s_magic != EXT4_SUPER_MAGIC)
4411                 goto cantfind_ext4;
4412         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
4413
4414         /* Warn if metadata_csum and gdt_csum are both set. */
4415         if (ext4_has_feature_metadata_csum(sb) &&
4416             ext4_has_feature_gdt_csum(sb))
4417                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4418                              "redundant flags; please run fsck.");
4419
4420         /* Check for a known checksum algorithm */
4421         if (!ext4_verify_csum_type(sb, es)) {
4422                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4423                          "unknown checksum algorithm.");
4424                 silent = 1;
4425                 goto cantfind_ext4;
4426         }
4427         ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4428                                 ext4_orphan_file_block_trigger);
4429
4430         /* Load the checksum driver */
4431         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4432         if (IS_ERR(sbi->s_chksum_driver)) {
4433                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4434                 ret = PTR_ERR(sbi->s_chksum_driver);
4435                 sbi->s_chksum_driver = NULL;
4436                 goto failed_mount;
4437         }
4438
4439         /* Check superblock checksum */
4440         if (!ext4_superblock_csum_verify(sb, es)) {
4441                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4442                          "invalid superblock checksum.  Run e2fsck?");
4443                 silent = 1;
4444                 ret = -EFSBADCRC;
4445                 goto cantfind_ext4;
4446         }
4447
4448         /* Precompute checksum seed for all metadata */
4449         if (ext4_has_feature_csum_seed(sb))
4450                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4451         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4452                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4453                                                sizeof(es->s_uuid));
4454
4455         /* Set defaults before we parse the mount options */
4456         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4457         set_opt(sb, INIT_INODE_TABLE);
4458         if (def_mount_opts & EXT4_DEFM_DEBUG)
4459                 set_opt(sb, DEBUG);
4460         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4461                 set_opt(sb, GRPID);
4462         if (def_mount_opts & EXT4_DEFM_UID16)
4463                 set_opt(sb, NO_UID32);
4464         /* xattr user namespace & acls are now defaulted on */
4465         set_opt(sb, XATTR_USER);
4466 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4467         set_opt(sb, POSIX_ACL);
4468 #endif
4469         if (ext4_has_feature_fast_commit(sb))
4470                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4471         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4472         if (ext4_has_metadata_csum(sb))
4473                 set_opt(sb, JOURNAL_CHECKSUM);
4474
4475         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4476                 set_opt(sb, JOURNAL_DATA);
4477         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4478                 set_opt(sb, ORDERED_DATA);
4479         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4480                 set_opt(sb, WRITEBACK_DATA);
4481
4482         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4483                 set_opt(sb, ERRORS_PANIC);
4484         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4485                 set_opt(sb, ERRORS_CONT);
4486         else
4487                 set_opt(sb, ERRORS_RO);
4488         /* block_validity enabled by default; disable with noblock_validity */
4489         set_opt(sb, BLOCK_VALIDITY);
4490         if (def_mount_opts & EXT4_DEFM_DISCARD)
4491                 set_opt(sb, DISCARD);
4492
4493         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4494         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4495         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4496         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4497         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4498
4499         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4500                 set_opt(sb, BARRIER);
4501
4502         /*
4503          * enable delayed allocation by default
4504          * Use -o nodelalloc to turn it off
4505          */
4506         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4507             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4508                 set_opt(sb, DELALLOC);
4509
4510         /*
4511          * set default s_li_wait_mult for lazyinit, for the case there is
4512          * no mount option specified.
4513          */
4514         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4515
4516         if (le32_to_cpu(es->s_log_block_size) >
4517             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4518                 ext4_msg(sb, KERN_ERR,
4519                          "Invalid log block size: %u",
4520                          le32_to_cpu(es->s_log_block_size));
4521                 goto failed_mount;
4522         }
4523         if (le32_to_cpu(es->s_log_cluster_size) >
4524             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4525                 ext4_msg(sb, KERN_ERR,
4526                          "Invalid log cluster size: %u",
4527                          le32_to_cpu(es->s_log_cluster_size));
4528                 goto failed_mount;
4529         }
4530
4531         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4532
4533         if (blocksize == PAGE_SIZE)
4534                 set_opt(sb, DIOREAD_NOLOCK);
4535
4536         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4537                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4538                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4539         } else {
4540                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4541                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4542                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4543                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4544                                  sbi->s_first_ino);
4545                         goto failed_mount;
4546                 }
4547                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4548                     (!is_power_of_2(sbi->s_inode_size)) ||
4549                     (sbi->s_inode_size > blocksize)) {
4550                         ext4_msg(sb, KERN_ERR,
4551                                "unsupported inode size: %d",
4552                                sbi->s_inode_size);
4553                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4554                         goto failed_mount;
4555                 }
4556                 /*
4557                  * i_atime_extra is the last extra field available for
4558                  * [acm]times in struct ext4_inode. Checking for that
4559                  * field should suffice to ensure we have extra space
4560                  * for all three.
4561                  */
4562                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4563                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4564                         sb->s_time_gran = 1;
4565                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4566                 } else {
4567                         sb->s_time_gran = NSEC_PER_SEC;
4568                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4569                 }
4570                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4571         }
4572         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4573                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4574                         EXT4_GOOD_OLD_INODE_SIZE;
4575                 if (ext4_has_feature_extra_isize(sb)) {
4576                         unsigned v, max = (sbi->s_inode_size -
4577                                            EXT4_GOOD_OLD_INODE_SIZE);
4578
4579                         v = le16_to_cpu(es->s_want_extra_isize);
4580                         if (v > max) {
4581                                 ext4_msg(sb, KERN_ERR,
4582                                          "bad s_want_extra_isize: %d", v);
4583                                 goto failed_mount;
4584                         }
4585                         if (sbi->s_want_extra_isize < v)
4586                                 sbi->s_want_extra_isize = v;
4587
4588                         v = le16_to_cpu(es->s_min_extra_isize);
4589                         if (v > max) {
4590                                 ext4_msg(sb, KERN_ERR,
4591                                          "bad s_min_extra_isize: %d", v);
4592                                 goto failed_mount;
4593                         }
4594                         if (sbi->s_want_extra_isize < v)
4595                                 sbi->s_want_extra_isize = v;
4596                 }
4597         }
4598
4599         err = parse_apply_sb_mount_options(sb, ctx);
4600         if (err < 0)
4601                 goto failed_mount;
4602
4603         sbi->s_def_mount_opt = sbi->s_mount_opt;
4604
4605         err = ext4_check_opt_consistency(fc, sb);
4606         if (err < 0)
4607                 goto failed_mount;
4608
4609         err = ext4_apply_options(fc, sb);
4610         if (err < 0)
4611                 goto failed_mount;
4612
4613 #ifdef CONFIG_UNICODE
4614         if (ext4_has_feature_casefold(sb) && !sb->s_encoding) {
4615                 const struct ext4_sb_encodings *encoding_info;
4616                 struct unicode_map *encoding;
4617                 __u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4618
4619                 encoding_info = ext4_sb_read_encoding(es);
4620                 if (!encoding_info) {
4621                         ext4_msg(sb, KERN_ERR,
4622                                  "Encoding requested by superblock is unknown");
4623                         goto failed_mount;
4624                 }
4625
4626                 encoding = utf8_load(encoding_info->version);
4627                 if (IS_ERR(encoding)) {
4628                         ext4_msg(sb, KERN_ERR,
4629                                  "can't mount with superblock charset: %s-%u.%u.%u "
4630                                  "not supported by the kernel. flags: 0x%x.",
4631                                  encoding_info->name,
4632                                  unicode_major(encoding_info->version),
4633                                  unicode_minor(encoding_info->version),
4634                                  unicode_rev(encoding_info->version),
4635                                  encoding_flags);
4636                         goto failed_mount;
4637                 }
4638                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4639                          "%s-%u.%u.%u with flags 0x%hx", encoding_info->name,
4640                          unicode_major(encoding_info->version),
4641                          unicode_minor(encoding_info->version),
4642                          unicode_rev(encoding_info->version),
4643                          encoding_flags);
4644
4645                 sb->s_encoding = encoding;
4646                 sb->s_encoding_flags = encoding_flags;
4647         }
4648 #endif
4649
4650         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4651                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!\n");
4652                 /* can't mount with both data=journal and dioread_nolock. */
4653                 clear_opt(sb, DIOREAD_NOLOCK);
4654                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4655                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4656                         ext4_msg(sb, KERN_ERR, "can't mount with "
4657                                  "both data=journal and delalloc");
4658                         goto failed_mount;
4659                 }
4660                 if (test_opt(sb, DAX_ALWAYS)) {
4661                         ext4_msg(sb, KERN_ERR, "can't mount with "
4662                                  "both data=journal and dax");
4663                         goto failed_mount;
4664                 }
4665                 if (ext4_has_feature_encrypt(sb)) {
4666                         ext4_msg(sb, KERN_WARNING,
4667                                  "encrypted files will use data=ordered "
4668                                  "instead of data journaling mode");
4669                 }
4670                 if (test_opt(sb, DELALLOC))
4671                         clear_opt(sb, DELALLOC);
4672         } else {
4673                 sb->s_iflags |= SB_I_CGROUPWB;
4674         }
4675
4676         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4677                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4678
4679         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4680             (ext4_has_compat_features(sb) ||
4681              ext4_has_ro_compat_features(sb) ||
4682              ext4_has_incompat_features(sb)))
4683                 ext4_msg(sb, KERN_WARNING,
4684                        "feature flags set on rev 0 fs, "
4685                        "running e2fsck is recommended");
4686
4687         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4688                 set_opt2(sb, HURD_COMPAT);
4689                 if (ext4_has_feature_64bit(sb)) {
4690                         ext4_msg(sb, KERN_ERR,
4691                                  "The Hurd can't support 64-bit file systems");
4692                         goto failed_mount;
4693                 }
4694
4695                 /*
4696                  * ea_inode feature uses l_i_version field which is not
4697                  * available in HURD_COMPAT mode.
4698                  */
4699                 if (ext4_has_feature_ea_inode(sb)) {
4700                         ext4_msg(sb, KERN_ERR,
4701                                  "ea_inode feature is not supported for Hurd");
4702                         goto failed_mount;
4703                 }
4704         }
4705
4706         if (IS_EXT2_SB(sb)) {
4707                 if (ext2_feature_set_ok(sb))
4708                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4709                                  "using the ext4 subsystem");
4710                 else {
4711                         /*
4712                          * If we're probing be silent, if this looks like
4713                          * it's actually an ext[34] filesystem.
4714                          */
4715                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4716                                 goto failed_mount;
4717                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4718                                  "to feature incompatibilities");
4719                         goto failed_mount;
4720                 }
4721         }
4722
4723         if (IS_EXT3_SB(sb)) {
4724                 if (ext3_feature_set_ok(sb))
4725                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4726                                  "using the ext4 subsystem");
4727                 else {
4728                         /*
4729                          * If we're probing be silent, if this looks like
4730                          * it's actually an ext4 filesystem.
4731                          */
4732                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4733                                 goto failed_mount;
4734                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4735                                  "to feature incompatibilities");
4736                         goto failed_mount;
4737                 }
4738         }
4739
4740         /*
4741          * Check feature flags regardless of the revision level, since we
4742          * previously didn't change the revision level when setting the flags,
4743          * so there is a chance incompat flags are set on a rev 0 filesystem.
4744          */
4745         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4746                 goto failed_mount;
4747
4748         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4749                 ext4_msg(sb, KERN_ERR,
4750                          "Number of reserved GDT blocks insanely large: %d",
4751                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4752                 goto failed_mount;
4753         }
4754
4755         if (sbi->s_daxdev) {
4756                 if (blocksize == PAGE_SIZE)
4757                         set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4758                 else
4759                         ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
4760         }
4761
4762         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4763                 if (ext4_has_feature_inline_data(sb)) {
4764                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4765                                         " that may contain inline data");
4766                         goto failed_mount;
4767                 }
4768                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4769                         ext4_msg(sb, KERN_ERR,
4770                                 "DAX unsupported by block device.");
4771                         goto failed_mount;
4772                 }
4773         }
4774
4775         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4776                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4777                          es->s_encryption_level);
4778                 goto failed_mount;
4779         }
4780
4781         if (sb->s_blocksize != blocksize) {
4782                 /*
4783                  * bh must be released before kill_bdev(), otherwise
4784                  * it won't be freed and its page also. kill_bdev()
4785                  * is called by sb_set_blocksize().
4786                  */
4787                 brelse(bh);
4788                 /* Validate the filesystem blocksize */
4789                 if (!sb_set_blocksize(sb, blocksize)) {
4790                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4791                                         blocksize);
4792                         bh = NULL;
4793                         goto failed_mount;
4794                 }
4795
4796                 logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
4797                 offset = do_div(logical_sb_block, blocksize);
4798                 bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4799                 if (IS_ERR(bh)) {
4800                         ext4_msg(sb, KERN_ERR,
4801                                "Can't read superblock on 2nd try");
4802                         ret = PTR_ERR(bh);
4803                         bh = NULL;
4804                         goto failed_mount;
4805                 }
4806                 es = (struct ext4_super_block *)(bh->b_data + offset);
4807                 sbi->s_es = es;
4808                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4809                         ext4_msg(sb, KERN_ERR,
4810                                "Magic mismatch, very weird!");
4811                         goto failed_mount;
4812                 }
4813         }
4814
4815         has_huge_files = ext4_has_feature_huge_file(sb);
4816         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4817                                                       has_huge_files);
4818         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4819
4820         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4821         if (ext4_has_feature_64bit(sb)) {
4822                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4823                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4824                     !is_power_of_2(sbi->s_desc_size)) {
4825                         ext4_msg(sb, KERN_ERR,
4826                                "unsupported descriptor size %lu",
4827                                sbi->s_desc_size);
4828                         goto failed_mount;
4829                 }
4830         } else
4831                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4832
4833         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4834         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4835
4836         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4837         if (sbi->s_inodes_per_block == 0)
4838                 goto cantfind_ext4;
4839         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4840             sbi->s_inodes_per_group > blocksize * 8) {
4841                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4842                          sbi->s_inodes_per_group);
4843                 goto failed_mount;
4844         }
4845         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4846                                         sbi->s_inodes_per_block;
4847         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4848         sbi->s_sbh = bh;
4849         sbi->s_mount_state = le16_to_cpu(es->s_state);
4850         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4851         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4852
4853         for (i = 0; i < 4; i++)
4854                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4855         sbi->s_def_hash_version = es->s_def_hash_version;
4856         if (ext4_has_feature_dir_index(sb)) {
4857                 i = le32_to_cpu(es->s_flags);
4858                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4859                         sbi->s_hash_unsigned = 3;
4860                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4861 #ifdef __CHAR_UNSIGNED__
4862                         if (!sb_rdonly(sb))
4863                                 es->s_flags |=
4864                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4865                         sbi->s_hash_unsigned = 3;
4866 #else
4867                         if (!sb_rdonly(sb))
4868                                 es->s_flags |=
4869                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4870 #endif
4871                 }
4872         }
4873
4874         /* Handle clustersize */
4875         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4876         if (ext4_has_feature_bigalloc(sb)) {
4877                 if (clustersize < blocksize) {
4878                         ext4_msg(sb, KERN_ERR,
4879                                  "cluster size (%d) smaller than "
4880                                  "block size (%d)", clustersize, blocksize);
4881                         goto failed_mount;
4882                 }
4883                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4884                         le32_to_cpu(es->s_log_block_size);
4885                 sbi->s_clusters_per_group =
4886                         le32_to_cpu(es->s_clusters_per_group);
4887                 if (sbi->s_clusters_per_group > blocksize * 8) {
4888                         ext4_msg(sb, KERN_ERR,
4889                                  "#clusters per group too big: %lu",
4890                                  sbi->s_clusters_per_group);
4891                         goto failed_mount;
4892                 }
4893                 if (sbi->s_blocks_per_group !=
4894                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4895                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4896                                  "clusters per group (%lu) inconsistent",
4897                                  sbi->s_blocks_per_group,
4898                                  sbi->s_clusters_per_group);
4899                         goto failed_mount;
4900                 }
4901         } else {
4902                 if (clustersize != blocksize) {
4903                         ext4_msg(sb, KERN_ERR,
4904                                  "fragment/cluster size (%d) != "
4905                                  "block size (%d)", clustersize, blocksize);
4906                         goto failed_mount;
4907                 }
4908                 if (sbi->s_blocks_per_group > blocksize * 8) {
4909                         ext4_msg(sb, KERN_ERR,
4910                                  "#blocks per group too big: %lu",
4911                                  sbi->s_blocks_per_group);
4912                         goto failed_mount;
4913                 }
4914                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4915                 sbi->s_cluster_bits = 0;
4916         }
4917         sbi->s_cluster_ratio = clustersize / blocksize;
4918
4919         /* Do we have standard group size of clustersize * 8 blocks ? */
4920         if (sbi->s_blocks_per_group == clustersize << 3)
4921                 set_opt2(sb, STD_GROUP_SIZE);
4922
4923         /*
4924          * Test whether we have more sectors than will fit in sector_t,
4925          * and whether the max offset is addressable by the page cache.
4926          */
4927         err = generic_check_addressable(sb->s_blocksize_bits,
4928                                         ext4_blocks_count(es));
4929         if (err) {
4930                 ext4_msg(sb, KERN_ERR, "filesystem"
4931                          " too large to mount safely on this system");
4932                 goto failed_mount;
4933         }
4934
4935         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4936                 goto cantfind_ext4;
4937
4938         /* check blocks count against device size */
4939         blocks_count = sb_bdev_nr_blocks(sb);
4940         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4941                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4942                        "exceeds size of device (%llu blocks)",
4943                        ext4_blocks_count(es), blocks_count);
4944                 goto failed_mount;
4945         }
4946
4947         /*
4948          * It makes no sense for the first data block to be beyond the end
4949          * of the filesystem.
4950          */
4951         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4952                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4953                          "block %u is beyond end of filesystem (%llu)",
4954                          le32_to_cpu(es->s_first_data_block),
4955                          ext4_blocks_count(es));
4956                 goto failed_mount;
4957         }
4958         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4959             (sbi->s_cluster_ratio == 1)) {
4960                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4961                          "block is 0 with a 1k block and cluster size");
4962                 goto failed_mount;
4963         }
4964
4965         blocks_count = (ext4_blocks_count(es) -
4966                         le32_to_cpu(es->s_first_data_block) +
4967                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4968         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4969         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4970                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4971                        "(block count %llu, first data block %u, "
4972                        "blocks per group %lu)", blocks_count,
4973                        ext4_blocks_count(es),
4974                        le32_to_cpu(es->s_first_data_block),
4975                        EXT4_BLOCKS_PER_GROUP(sb));
4976                 goto failed_mount;
4977         }
4978         sbi->s_groups_count = blocks_count;
4979         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4980                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4981         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4982             le32_to_cpu(es->s_inodes_count)) {
4983                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4984                          le32_to_cpu(es->s_inodes_count),
4985                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4986                 ret = -EINVAL;
4987                 goto failed_mount;
4988         }
4989         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4990                    EXT4_DESC_PER_BLOCK(sb);
4991         if (ext4_has_feature_meta_bg(sb)) {
4992                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4993                         ext4_msg(sb, KERN_WARNING,
4994                                  "first meta block group too large: %u "
4995                                  "(group descriptor block count %u)",
4996                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4997                         goto failed_mount;
4998                 }
4999         }
5000         rcu_assign_pointer(sbi->s_group_desc,
5001                            kvmalloc_array(db_count,
5002                                           sizeof(struct buffer_head *),
5003                                           GFP_KERNEL));
5004         if (sbi->s_group_desc == NULL) {
5005                 ext4_msg(sb, KERN_ERR, "not enough memory");
5006                 ret = -ENOMEM;
5007                 goto failed_mount;
5008         }
5009
5010         bgl_lock_init(sbi->s_blockgroup_lock);
5011
5012         /* Pre-read the descriptors into the buffer cache */
5013         for (i = 0; i < db_count; i++) {
5014                 block = descriptor_loc(sb, logical_sb_block, i);
5015                 ext4_sb_breadahead_unmovable(sb, block);
5016         }
5017
5018         for (i = 0; i < db_count; i++) {
5019                 struct buffer_head *bh;
5020
5021                 block = descriptor_loc(sb, logical_sb_block, i);
5022                 bh = ext4_sb_bread_unmovable(sb, block);
5023                 if (IS_ERR(bh)) {
5024                         ext4_msg(sb, KERN_ERR,
5025                                "can't read group descriptor %d", i);
5026                         db_count = i;
5027                         ret = PTR_ERR(bh);
5028                         goto failed_mount2;
5029                 }
5030                 rcu_read_lock();
5031                 rcu_dereference(sbi->s_group_desc)[i] = bh;
5032                 rcu_read_unlock();
5033         }
5034         sbi->s_gdb_count = db_count;
5035         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
5036                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
5037                 ret = -EFSCORRUPTED;
5038                 goto failed_mount2;
5039         }
5040
5041         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5042         spin_lock_init(&sbi->s_error_lock);
5043         INIT_WORK(&sbi->s_error_work, flush_stashed_error_work);
5044
5045         /* Register extent status tree shrinker */
5046         if (ext4_es_register_shrinker(sbi))
5047                 goto failed_mount3;
5048
5049         sbi->s_stripe = ext4_get_stripe_size(sbi);
5050         sbi->s_extent_max_zeroout_kb = 32;
5051
5052         /*
5053          * set up enough so that it can read an inode
5054          */
5055         sb->s_op = &ext4_sops;
5056         sb->s_export_op = &ext4_export_ops;
5057         sb->s_xattr = ext4_xattr_handlers;
5058 #ifdef CONFIG_FS_ENCRYPTION
5059         sb->s_cop = &ext4_cryptops;
5060 #endif
5061 #ifdef CONFIG_FS_VERITY
5062         sb->s_vop = &ext4_verityops;
5063 #endif
5064 #ifdef CONFIG_QUOTA
5065         sb->dq_op = &ext4_quota_operations;
5066         if (ext4_has_feature_quota(sb))
5067                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
5068         else
5069                 sb->s_qcop = &ext4_qctl_operations;
5070         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5071 #endif
5072         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
5073
5074         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5075         mutex_init(&sbi->s_orphan_lock);
5076
5077         /* Initialize fast commit stuff */
5078         atomic_set(&sbi->s_fc_subtid, 0);
5079         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
5080         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
5081         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
5082         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
5083         sbi->s_fc_bytes = 0;
5084         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
5085         ext4_clear_mount_flag(sb, EXT4_MF_FC_COMMITTING);
5086         spin_lock_init(&sbi->s_fc_lock);
5087         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
5088         sbi->s_fc_replay_state.fc_regions = NULL;
5089         sbi->s_fc_replay_state.fc_regions_size = 0;
5090         sbi->s_fc_replay_state.fc_regions_used = 0;
5091         sbi->s_fc_replay_state.fc_regions_valid = 0;
5092         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
5093         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
5094         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
5095
5096         sb->s_root = NULL;
5097
5098         needs_recovery = (es->s_last_orphan != 0 ||
5099                           ext4_has_feature_orphan_present(sb) ||
5100                           ext4_has_feature_journal_needs_recovery(sb));
5101
5102         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
5103                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
5104                         goto failed_mount3a;
5105
5106         /*
5107          * The first inode we look at is the journal inode.  Don't try
5108          * root first: it may be modified in the journal!
5109          */
5110         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5111                 err = ext4_load_journal(sb, es, ctx->journal_devnum);
5112                 if (err)
5113                         goto failed_mount3a;
5114         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5115                    ext4_has_feature_journal_needs_recovery(sb)) {
5116                 ext4_msg(sb, KERN_ERR, "required journal recovery "
5117                        "suppressed and not mounted read-only");
5118                 goto failed_mount_wq;
5119         } else {
5120                 /* Nojournal mode, all journal mount options are illegal */
5121                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
5122                         ext4_msg(sb, KERN_ERR, "can't mount with "
5123                                  "journal_checksum, fs mounted w/o journal");
5124                         goto failed_mount_wq;
5125                 }
5126                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5127                         ext4_msg(sb, KERN_ERR, "can't mount with "
5128                                  "journal_async_commit, fs mounted w/o journal");
5129                         goto failed_mount_wq;
5130                 }
5131                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
5132                         ext4_msg(sb, KERN_ERR, "can't mount with "
5133                                  "commit=%lu, fs mounted w/o journal",
5134                                  sbi->s_commit_interval / HZ);
5135                         goto failed_mount_wq;
5136                 }
5137                 if (EXT4_MOUNT_DATA_FLAGS &
5138                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
5139                         ext4_msg(sb, KERN_ERR, "can't mount with "
5140                                  "data=, fs mounted w/o journal");
5141                         goto failed_mount_wq;
5142                 }
5143                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5144                 clear_opt(sb, JOURNAL_CHECKSUM);
5145                 clear_opt(sb, DATA_FLAGS);
5146                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
5147                 sbi->s_journal = NULL;
5148                 needs_recovery = 0;
5149                 goto no_journal;
5150         }
5151
5152         if (ext4_has_feature_64bit(sb) &&
5153             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
5154                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
5155                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
5156                 goto failed_mount_wq;
5157         }
5158
5159         if (!set_journal_csum_feature_set(sb)) {
5160                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
5161                          "feature set");
5162                 goto failed_mount_wq;
5163         }
5164
5165         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
5166                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
5167                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
5168                 ext4_msg(sb, KERN_ERR,
5169                         "Failed to set fast commit journal feature");
5170                 goto failed_mount_wq;
5171         }
5172
5173         /* We have now updated the journal if required, so we can
5174          * validate the data journaling mode. */
5175         switch (test_opt(sb, DATA_FLAGS)) {
5176         case 0:
5177                 /* No mode set, assume a default based on the journal
5178                  * capabilities: ORDERED_DATA if the journal can
5179                  * cope, else JOURNAL_DATA
5180                  */
5181                 if (jbd2_journal_check_available_features
5182                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
5183                         set_opt(sb, ORDERED_DATA);
5184                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
5185                 } else {
5186                         set_opt(sb, JOURNAL_DATA);
5187                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
5188                 }
5189                 break;
5190
5191         case EXT4_MOUNT_ORDERED_DATA:
5192         case EXT4_MOUNT_WRITEBACK_DATA:
5193                 if (!jbd2_journal_check_available_features
5194                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
5195                         ext4_msg(sb, KERN_ERR, "Journal does not support "
5196                                "requested data journaling mode");
5197                         goto failed_mount_wq;
5198                 }
5199                 break;
5200         default:
5201                 break;
5202         }
5203
5204         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
5205             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5206                 ext4_msg(sb, KERN_ERR, "can't mount with "
5207                         "journal_async_commit in data=ordered mode");
5208                 goto failed_mount_wq;
5209         }
5210
5211         set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
5212
5213         sbi->s_journal->j_submit_inode_data_buffers =
5214                 ext4_journal_submit_inode_data_buffers;
5215         sbi->s_journal->j_finish_inode_data_buffers =
5216                 ext4_journal_finish_inode_data_buffers;
5217
5218 no_journal:
5219         if (!test_opt(sb, NO_MBCACHE)) {
5220                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
5221                 if (!sbi->s_ea_block_cache) {
5222                         ext4_msg(sb, KERN_ERR,
5223                                  "Failed to create ea_block_cache");
5224                         goto failed_mount_wq;
5225                 }
5226
5227                 if (ext4_has_feature_ea_inode(sb)) {
5228                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5229                         if (!sbi->s_ea_inode_cache) {
5230                                 ext4_msg(sb, KERN_ERR,
5231                                          "Failed to create ea_inode_cache");
5232                                 goto failed_mount_wq;
5233                         }
5234                 }
5235         }
5236
5237         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
5238                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
5239                 goto failed_mount_wq;
5240         }
5241
5242         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
5243             !ext4_has_feature_encrypt(sb)) {
5244                 ext4_set_feature_encrypt(sb);
5245                 ext4_commit_super(sb);
5246         }
5247
5248         /*
5249          * Get the # of file system overhead blocks from the
5250          * superblock if present.
5251          */
5252         if (es->s_overhead_clusters)
5253                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5254         else {
5255                 err = ext4_calculate_overhead(sb);
5256                 if (err)
5257                         goto failed_mount_wq;
5258         }
5259
5260         /*
5261          * The maximum number of concurrent works can be high and
5262          * concurrency isn't really necessary.  Limit it to 1.
5263          */
5264         EXT4_SB(sb)->rsv_conversion_wq =
5265                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5266         if (!EXT4_SB(sb)->rsv_conversion_wq) {
5267                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5268                 ret = -ENOMEM;
5269                 goto failed_mount4;
5270         }
5271
5272         /*
5273          * The jbd2_journal_load will have done any necessary log recovery,
5274          * so we can safely mount the rest of the filesystem now.
5275          */
5276
5277         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5278         if (IS_ERR(root)) {
5279                 ext4_msg(sb, KERN_ERR, "get root inode failed");
5280                 ret = PTR_ERR(root);
5281                 root = NULL;
5282                 goto failed_mount4;
5283         }
5284         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5285                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5286                 iput(root);
5287                 goto failed_mount4;
5288         }
5289
5290         sb->s_root = d_make_root(root);
5291         if (!sb->s_root) {
5292                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
5293                 ret = -ENOMEM;
5294                 goto failed_mount4;
5295         }
5296
5297         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
5298         if (ret == -EROFS) {
5299                 sb->s_flags |= SB_RDONLY;
5300                 ret = 0;
5301         } else if (ret)
5302                 goto failed_mount4a;
5303
5304         ext4_set_resv_clusters(sb);
5305
5306         if (test_opt(sb, BLOCK_VALIDITY)) {
5307                 err = ext4_setup_system_zone(sb);
5308                 if (err) {
5309                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
5310                                  "zone (%d)", err);
5311                         goto failed_mount4a;
5312                 }
5313         }
5314         ext4_fc_replay_cleanup(sb);
5315
5316         ext4_ext_init(sb);
5317
5318         /*
5319          * Enable optimize_scan if number of groups is > threshold. This can be
5320          * turned off by passing "mb_optimize_scan=0". This can also be
5321          * turned on forcefully by passing "mb_optimize_scan=1".
5322          */
5323         if (ctx->mb_optimize_scan == 1)
5324                 set_opt2(sb, MB_OPTIMIZE_SCAN);
5325         else if (ctx->mb_optimize_scan == 0)
5326                 clear_opt2(sb, MB_OPTIMIZE_SCAN);
5327         else if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5328                 set_opt2(sb, MB_OPTIMIZE_SCAN);
5329
5330         err = ext4_mb_init(sb);
5331         if (err) {
5332                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5333                          err);
5334                 goto failed_mount5;
5335         }
5336
5337         /*
5338          * We can only set up the journal commit callback once
5339          * mballoc is initialized
5340          */
5341         if (sbi->s_journal)
5342                 sbi->s_journal->j_commit_callback =
5343                         ext4_journal_commit_callback;
5344
5345         block = ext4_count_free_clusters(sb);
5346         ext4_free_blocks_count_set(sbi->s_es,
5347                                    EXT4_C2B(sbi, block));
5348         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
5349                                   GFP_KERNEL);
5350         if (!err) {
5351                 unsigned long freei = ext4_count_free_inodes(sb);
5352                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
5353                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
5354                                           GFP_KERNEL);
5355         }
5356         /*
5357          * Update the checksum after updating free space/inode
5358          * counters.  Otherwise the superblock can have an incorrect
5359          * checksum in the buffer cache until it is written out and
5360          * e2fsprogs programs trying to open a file system immediately
5361          * after it is mounted can fail.
5362          */
5363         ext4_superblock_csum_set(sb);
5364         if (!err)
5365                 err = percpu_counter_init(&sbi->s_dirs_counter,
5366                                           ext4_count_dirs(sb), GFP_KERNEL);
5367         if (!err)
5368                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5369                                           GFP_KERNEL);
5370         if (!err)
5371                 err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
5372                                           GFP_KERNEL);
5373         if (!err)
5374                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5375
5376         if (err) {
5377                 ext4_msg(sb, KERN_ERR, "insufficient memory");
5378                 goto failed_mount6;
5379         }
5380
5381         if (ext4_has_feature_flex_bg(sb))
5382                 if (!ext4_fill_flex_info(sb)) {
5383                         ext4_msg(sb, KERN_ERR,
5384                                "unable to initialize "
5385                                "flex_bg meta info!");
5386                         ret = -ENOMEM;
5387                         goto failed_mount6;
5388                 }
5389
5390         err = ext4_register_li_request(sb, first_not_zeroed);
5391         if (err)
5392                 goto failed_mount6;
5393
5394         err = ext4_register_sysfs(sb);
5395         if (err)
5396                 goto failed_mount7;
5397
5398         err = ext4_init_orphan_info(sb);
5399         if (err)
5400                 goto failed_mount8;
5401 #ifdef CONFIG_QUOTA
5402         /* Enable quota usage during mount. */
5403         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5404                 err = ext4_enable_quotas(sb);
5405                 if (err)
5406                         goto failed_mount9;
5407         }
5408 #endif  /* CONFIG_QUOTA */
5409
5410         /*
5411          * Save the original bdev mapping's wb_err value which could be
5412          * used to detect the metadata async write error.
5413          */
5414         spin_lock_init(&sbi->s_bdev_wb_lock);
5415         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5416                                  &sbi->s_bdev_wb_err);
5417         sb->s_bdev->bd_super = sb;
5418         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5419         ext4_orphan_cleanup(sb, es);
5420         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5421         if (needs_recovery) {
5422                 ext4_msg(sb, KERN_INFO, "recovery complete");
5423                 err = ext4_mark_recovery_complete(sb, es);
5424                 if (err)
5425                         goto failed_mount9;
5426         }
5427
5428         if (test_opt(sb, DISCARD)) {
5429                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
5430                 if (!blk_queue_discard(q))
5431                         ext4_msg(sb, KERN_WARNING,
5432                                  "mounting with \"discard\" option, but "
5433                                  "the device does not support discard");
5434         }
5435
5436         if (es->s_error_count)
5437                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5438
5439         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5440         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5441         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5442         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5443         atomic_set(&sbi->s_warning_count, 0);
5444         atomic_set(&sbi->s_msg_count, 0);
5445
5446         return 0;
5447
5448 cantfind_ext4:
5449         if (!silent)
5450                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5451         goto failed_mount;
5452
5453 failed_mount9:
5454         ext4_release_orphan_info(sb);
5455 failed_mount8:
5456         ext4_unregister_sysfs(sb);
5457         kobject_put(&sbi->s_kobj);
5458 failed_mount7:
5459         ext4_unregister_li_request(sb);
5460 failed_mount6:
5461         ext4_mb_release(sb);
5462         rcu_read_lock();
5463         flex_groups = rcu_dereference(sbi->s_flex_groups);
5464         if (flex_groups) {
5465                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5466                         kvfree(flex_groups[i]);
5467                 kvfree(flex_groups);
5468         }
5469         rcu_read_unlock();
5470         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5471         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5472         percpu_counter_destroy(&sbi->s_dirs_counter);
5473         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5474         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
5475         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5476 failed_mount5:
5477         ext4_ext_release(sb);
5478         ext4_release_system_zone(sb);
5479 failed_mount4a:
5480         dput(sb->s_root);
5481         sb->s_root = NULL;
5482 failed_mount4:
5483         ext4_msg(sb, KERN_ERR, "mount failed");
5484         if (EXT4_SB(sb)->rsv_conversion_wq)
5485                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5486 failed_mount_wq:
5487         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5488         sbi->s_ea_inode_cache = NULL;
5489
5490         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5491         sbi->s_ea_block_cache = NULL;
5492
5493         if (sbi->s_journal) {
5494                 /* flush s_error_work before journal destroy. */
5495                 flush_work(&sbi->s_error_work);
5496                 jbd2_journal_destroy(sbi->s_journal);
5497                 sbi->s_journal = NULL;
5498         }
5499 failed_mount3a:
5500         ext4_es_unregister_shrinker(sbi);
5501 failed_mount3:
5502         /* flush s_error_work before sbi destroy */
5503         flush_work(&sbi->s_error_work);
5504         del_timer_sync(&sbi->s_err_report);
5505         ext4_stop_mmpd(sbi);
5506 failed_mount2:
5507         rcu_read_lock();
5508         group_desc = rcu_dereference(sbi->s_group_desc);
5509         for (i = 0; i < db_count; i++)
5510                 brelse(group_desc[i]);
5511         kvfree(group_desc);
5512         rcu_read_unlock();
5513 failed_mount:
5514         if (sbi->s_chksum_driver)
5515                 crypto_free_shash(sbi->s_chksum_driver);
5516
5517 #ifdef CONFIG_UNICODE
5518         utf8_unload(sb->s_encoding);
5519 #endif
5520
5521 #ifdef CONFIG_QUOTA
5522         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5523                 kfree(get_qf_name(sb, sbi, i));
5524 #endif
5525         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5526         /* ext4_blkdev_remove() calls kill_bdev(), release bh before it. */
5527         brelse(bh);
5528         ext4_blkdev_remove(sbi);
5529 out_fail:
5530         sb->s_fs_info = NULL;
5531         return err ? err : ret;
5532 }
5533
5534 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5535 {
5536         struct ext4_fs_context *ctx = fc->fs_private;
5537         struct ext4_sb_info *sbi;
5538         const char *descr;
5539         int ret;
5540
5541         sbi = ext4_alloc_sbi(sb);
5542         if (!sbi)
5543                 ret = -ENOMEM;
5544
5545         fc->s_fs_info = sbi;
5546
5547         /* Cleanup superblock name */
5548         strreplace(sb->s_id, '/', '!');
5549
5550         sbi->s_sb_block = 1;    /* Default super block location */
5551         if (ctx->spec & EXT4_SPEC_s_sb_block)
5552                 sbi->s_sb_block = ctx->s_sb_block;
5553
5554         ret = __ext4_fill_super(fc, sb);
5555         if (ret < 0)
5556                 goto free_sbi;
5557
5558         if (sbi->s_journal) {
5559                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5560                         descr = " journalled data mode";
5561                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5562                         descr = " ordered data mode";
5563                 else
5564                         descr = " writeback data mode";
5565         } else
5566                 descr = "out journal";
5567
5568         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5569                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5570                          "Quota mode: %s.", descr, ext4_quota_mode(sb));
5571
5572         return 0;
5573
5574 free_sbi:
5575         ext4_free_sbi(sbi);
5576         fc->s_fs_info = NULL;
5577         return ret;
5578 }
5579
5580 static int ext4_get_tree(struct fs_context *fc)
5581 {
5582         return get_tree_bdev(fc, ext4_fill_super);
5583 }
5584
5585 /*
5586  * Setup any per-fs journal parameters now.  We'll do this both on
5587  * initial mount, once the journal has been initialised but before we've
5588  * done any recovery; and again on any subsequent remount.
5589  */
5590 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5591 {
5592         struct ext4_sb_info *sbi = EXT4_SB(sb);
5593
5594         journal->j_commit_interval = sbi->s_commit_interval;
5595         journal->j_min_batch_time = sbi->s_min_batch_time;
5596         journal->j_max_batch_time = sbi->s_max_batch_time;
5597         ext4_fc_init(sb, journal);
5598
5599         write_lock(&journal->j_state_lock);
5600         if (test_opt(sb, BARRIER))
5601                 journal->j_flags |= JBD2_BARRIER;
5602         else
5603                 journal->j_flags &= ~JBD2_BARRIER;
5604         if (test_opt(sb, DATA_ERR_ABORT))
5605                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5606         else
5607                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5608         write_unlock(&journal->j_state_lock);
5609 }
5610
5611 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5612                                              unsigned int journal_inum)
5613 {
5614         struct inode *journal_inode;
5615
5616         /*
5617          * Test for the existence of a valid inode on disk.  Bad things
5618          * happen if we iget() an unused inode, as the subsequent iput()
5619          * will try to delete it.
5620          */
5621         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5622         if (IS_ERR(journal_inode)) {
5623                 ext4_msg(sb, KERN_ERR, "no journal found");
5624                 return NULL;
5625         }
5626         if (!journal_inode->i_nlink) {
5627                 make_bad_inode(journal_inode);
5628                 iput(journal_inode);
5629                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5630                 return NULL;
5631         }
5632
5633         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5634                   journal_inode, journal_inode->i_size);
5635         if (!S_ISREG(journal_inode->i_mode)) {
5636                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5637                 iput(journal_inode);
5638                 return NULL;
5639         }
5640         return journal_inode;
5641 }
5642
5643 static journal_t *ext4_get_journal(struct super_block *sb,
5644                                    unsigned int journal_inum)
5645 {
5646         struct inode *journal_inode;
5647         journal_t *journal;
5648
5649         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5650                 return NULL;
5651
5652         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5653         if (!journal_inode)
5654                 return NULL;
5655
5656         journal = jbd2_journal_init_inode(journal_inode);
5657         if (!journal) {
5658                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5659                 iput(journal_inode);
5660                 return NULL;
5661         }
5662         journal->j_private = sb;
5663         ext4_init_journal_params(sb, journal);
5664         return journal;
5665 }
5666
5667 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5668                                        dev_t j_dev)
5669 {
5670         struct buffer_head *bh;
5671         journal_t *journal;
5672         ext4_fsblk_t start;
5673         ext4_fsblk_t len;
5674         int hblock, blocksize;
5675         ext4_fsblk_t sb_block;
5676         unsigned long offset;
5677         struct ext4_super_block *es;
5678         struct block_device *bdev;
5679
5680         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5681                 return NULL;
5682
5683         bdev = ext4_blkdev_get(j_dev, sb);
5684         if (bdev == NULL)
5685                 return NULL;
5686
5687         blocksize = sb->s_blocksize;
5688         hblock = bdev_logical_block_size(bdev);
5689         if (blocksize < hblock) {
5690                 ext4_msg(sb, KERN_ERR,
5691                         "blocksize too small for journal device");
5692                 goto out_bdev;
5693         }
5694
5695         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5696         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5697         set_blocksize(bdev, blocksize);
5698         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5699                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5700                        "external journal");
5701                 goto out_bdev;
5702         }
5703
5704         es = (struct ext4_super_block *) (bh->b_data + offset);
5705         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5706             !(le32_to_cpu(es->s_feature_incompat) &
5707               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5708                 ext4_msg(sb, KERN_ERR, "external journal has "
5709                                         "bad superblock");
5710                 brelse(bh);
5711                 goto out_bdev;
5712         }
5713
5714         if ((le32_to_cpu(es->s_feature_ro_compat) &
5715              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5716             es->s_checksum != ext4_superblock_csum(sb, es)) {
5717                 ext4_msg(sb, KERN_ERR, "external journal has "
5718                                        "corrupt superblock");
5719                 brelse(bh);
5720                 goto out_bdev;
5721         }
5722
5723         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5724                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5725                 brelse(bh);
5726                 goto out_bdev;
5727         }
5728
5729         len = ext4_blocks_count(es);
5730         start = sb_block + 1;
5731         brelse(bh);     /* we're done with the superblock */
5732
5733         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5734                                         start, len, blocksize);
5735         if (!journal) {
5736                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5737                 goto out_bdev;
5738         }
5739         journal->j_private = sb;
5740         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5741                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5742                 goto out_journal;
5743         }
5744         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5745                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5746                                         "user (unsupported) - %d",
5747                         be32_to_cpu(journal->j_superblock->s_nr_users));
5748                 goto out_journal;
5749         }
5750         EXT4_SB(sb)->s_journal_bdev = bdev;
5751         ext4_init_journal_params(sb, journal);
5752         return journal;
5753
5754 out_journal:
5755         jbd2_journal_destroy(journal);
5756 out_bdev:
5757         ext4_blkdev_put(bdev);
5758         return NULL;
5759 }
5760
5761 static int ext4_load_journal(struct super_block *sb,
5762                              struct ext4_super_block *es,
5763                              unsigned long journal_devnum)
5764 {
5765         journal_t *journal;
5766         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5767         dev_t journal_dev;
5768         int err = 0;
5769         int really_read_only;
5770         int journal_dev_ro;
5771
5772         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5773                 return -EFSCORRUPTED;
5774
5775         if (journal_devnum &&
5776             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5777                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5778                         "numbers have changed");
5779                 journal_dev = new_decode_dev(journal_devnum);
5780         } else
5781                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5782
5783         if (journal_inum && journal_dev) {
5784                 ext4_msg(sb, KERN_ERR,
5785                          "filesystem has both journal inode and journal device!");
5786                 return -EINVAL;
5787         }
5788
5789         if (journal_inum) {
5790                 journal = ext4_get_journal(sb, journal_inum);
5791                 if (!journal)
5792                         return -EINVAL;
5793         } else {
5794                 journal = ext4_get_dev_journal(sb, journal_dev);
5795                 if (!journal)
5796                         return -EINVAL;
5797         }
5798
5799         journal_dev_ro = bdev_read_only(journal->j_dev);
5800         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5801
5802         if (journal_dev_ro && !sb_rdonly(sb)) {
5803                 ext4_msg(sb, KERN_ERR,
5804                          "journal device read-only, try mounting with '-o ro'");
5805                 err = -EROFS;
5806                 goto err_out;
5807         }
5808
5809         /*
5810          * Are we loading a blank journal or performing recovery after a
5811          * crash?  For recovery, we need to check in advance whether we
5812          * can get read-write access to the device.
5813          */
5814         if (ext4_has_feature_journal_needs_recovery(sb)) {
5815                 if (sb_rdonly(sb)) {
5816                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5817                                         "required on readonly filesystem");
5818                         if (really_read_only) {
5819                                 ext4_msg(sb, KERN_ERR, "write access "
5820                                         "unavailable, cannot proceed "
5821                                         "(try mounting with noload)");
5822                                 err = -EROFS;
5823                                 goto err_out;
5824                         }
5825                         ext4_msg(sb, KERN_INFO, "write access will "
5826                                "be enabled during recovery");
5827                 }
5828         }
5829
5830         if (!(journal->j_flags & JBD2_BARRIER))
5831                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5832
5833         if (!ext4_has_feature_journal_needs_recovery(sb))
5834                 err = jbd2_journal_wipe(journal, !really_read_only);
5835         if (!err) {
5836                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5837                 if (save)
5838                         memcpy(save, ((char *) es) +
5839                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5840                 err = jbd2_journal_load(journal);
5841                 if (save)
5842                         memcpy(((char *) es) + EXT4_S_ERR_START,
5843                                save, EXT4_S_ERR_LEN);
5844                 kfree(save);
5845         }
5846
5847         if (err) {
5848                 ext4_msg(sb, KERN_ERR, "error loading journal");
5849                 goto err_out;
5850         }
5851
5852         EXT4_SB(sb)->s_journal = journal;
5853         err = ext4_clear_journal_err(sb, es);
5854         if (err) {
5855                 EXT4_SB(sb)->s_journal = NULL;
5856                 jbd2_journal_destroy(journal);
5857                 return err;
5858         }
5859
5860         if (!really_read_only && journal_devnum &&
5861             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5862                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5863
5864                 /* Make sure we flush the recovery flag to disk. */
5865                 ext4_commit_super(sb);
5866         }
5867
5868         return 0;
5869
5870 err_out:
5871         jbd2_journal_destroy(journal);
5872         return err;
5873 }
5874
5875 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
5876 static void ext4_update_super(struct super_block *sb)
5877 {
5878         struct ext4_sb_info *sbi = EXT4_SB(sb);
5879         struct ext4_super_block *es = sbi->s_es;
5880         struct buffer_head *sbh = sbi->s_sbh;
5881
5882         lock_buffer(sbh);
5883         /*
5884          * If the file system is mounted read-only, don't update the
5885          * superblock write time.  This avoids updating the superblock
5886          * write time when we are mounting the root file system
5887          * read/only but we need to replay the journal; at that point,
5888          * for people who are east of GMT and who make their clock
5889          * tick in localtime for Windows bug-for-bug compatibility,
5890          * the clock is set in the future, and this will cause e2fsck
5891          * to complain and force a full file system check.
5892          */
5893         if (!(sb->s_flags & SB_RDONLY))
5894                 ext4_update_tstamp(es, s_wtime);
5895         es->s_kbytes_written =
5896                 cpu_to_le64(sbi->s_kbytes_written +
5897                     ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
5898                       sbi->s_sectors_written_start) >> 1));
5899         if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
5900                 ext4_free_blocks_count_set(es,
5901                         EXT4_C2B(sbi, percpu_counter_sum_positive(
5902                                 &sbi->s_freeclusters_counter)));
5903         if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
5904                 es->s_free_inodes_count =
5905                         cpu_to_le32(percpu_counter_sum_positive(
5906                                 &sbi->s_freeinodes_counter));
5907         /* Copy error information to the on-disk superblock */
5908         spin_lock(&sbi->s_error_lock);
5909         if (sbi->s_add_error_count > 0) {
5910                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5911                 if (!es->s_first_error_time && !es->s_first_error_time_hi) {
5912                         __ext4_update_tstamp(&es->s_first_error_time,
5913                                              &es->s_first_error_time_hi,
5914                                              sbi->s_first_error_time);
5915                         strncpy(es->s_first_error_func, sbi->s_first_error_func,
5916                                 sizeof(es->s_first_error_func));
5917                         es->s_first_error_line =
5918                                 cpu_to_le32(sbi->s_first_error_line);
5919                         es->s_first_error_ino =
5920                                 cpu_to_le32(sbi->s_first_error_ino);
5921                         es->s_first_error_block =
5922                                 cpu_to_le64(sbi->s_first_error_block);
5923                         es->s_first_error_errcode =
5924                                 ext4_errno_to_code(sbi->s_first_error_code);
5925                 }
5926                 __ext4_update_tstamp(&es->s_last_error_time,
5927                                      &es->s_last_error_time_hi,
5928                                      sbi->s_last_error_time);
5929                 strncpy(es->s_last_error_func, sbi->s_last_error_func,
5930                         sizeof(es->s_last_error_func));
5931                 es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
5932                 es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
5933                 es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
5934                 es->s_last_error_errcode =
5935                                 ext4_errno_to_code(sbi->s_last_error_code);
5936                 /*
5937                  * Start the daily error reporting function if it hasn't been
5938                  * started already
5939                  */
5940                 if (!es->s_error_count)
5941                         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
5942                 le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
5943                 sbi->s_add_error_count = 0;
5944         }
5945         spin_unlock(&sbi->s_error_lock);
5946
5947         ext4_superblock_csum_set(sb);
5948         unlock_buffer(sbh);
5949 }
5950
5951 static int ext4_commit_super(struct super_block *sb)
5952 {
5953         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5954         int error = 0;
5955
5956         if (!sbh)
5957                 return -EINVAL;
5958         if (block_device_ejected(sb))
5959                 return -ENODEV;
5960
5961         ext4_update_super(sb);
5962
5963         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5964                 /*
5965                  * Oh, dear.  A previous attempt to write the
5966                  * superblock failed.  This could happen because the
5967                  * USB device was yanked out.  Or it could happen to
5968                  * be a transient write error and maybe the block will
5969                  * be remapped.  Nothing we can do but to retry the
5970                  * write and hope for the best.
5971                  */
5972                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5973                        "superblock detected");
5974                 clear_buffer_write_io_error(sbh);
5975                 set_buffer_uptodate(sbh);
5976         }
5977         BUFFER_TRACE(sbh, "marking dirty");
5978         mark_buffer_dirty(sbh);
5979         error = __sync_dirty_buffer(sbh,
5980                 REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5981         if (buffer_write_io_error(sbh)) {
5982                 ext4_msg(sb, KERN_ERR, "I/O error while writing "
5983                        "superblock");
5984                 clear_buffer_write_io_error(sbh);
5985                 set_buffer_uptodate(sbh);
5986         }
5987         return error;
5988 }
5989
5990 /*
5991  * Have we just finished recovery?  If so, and if we are mounting (or
5992  * remounting) the filesystem readonly, then we will end up with a
5993  * consistent fs on disk.  Record that fact.
5994  */
5995 static int ext4_mark_recovery_complete(struct super_block *sb,
5996                                        struct ext4_super_block *es)
5997 {
5998         int err;
5999         journal_t *journal = EXT4_SB(sb)->s_journal;
6000
6001         if (!ext4_has_feature_journal(sb)) {
6002                 if (journal != NULL) {
6003                         ext4_error(sb, "Journal got removed while the fs was "
6004                                    "mounted!");
6005                         return -EFSCORRUPTED;
6006                 }
6007                 return 0;
6008         }
6009         jbd2_journal_lock_updates(journal);
6010         err = jbd2_journal_flush(journal, 0);
6011         if (err < 0)
6012                 goto out;
6013
6014         if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6015             ext4_has_feature_orphan_present(sb))) {
6016                 if (!ext4_orphan_file_empty(sb)) {
6017                         ext4_error(sb, "Orphan file not empty on read-only fs.");
6018                         err = -EFSCORRUPTED;
6019                         goto out;
6020                 }
6021                 ext4_clear_feature_journal_needs_recovery(sb);
6022                 ext4_clear_feature_orphan_present(sb);
6023                 ext4_commit_super(sb);
6024         }
6025 out:
6026         jbd2_journal_unlock_updates(journal);
6027         return err;
6028 }
6029
6030 /*
6031  * If we are mounting (or read-write remounting) a filesystem whose journal
6032  * has recorded an error from a previous lifetime, move that error to the
6033  * main filesystem now.
6034  */
6035 static int ext4_clear_journal_err(struct super_block *sb,
6036                                    struct ext4_super_block *es)
6037 {
6038         journal_t *journal;
6039         int j_errno;
6040         const char *errstr;
6041
6042         if (!ext4_has_feature_journal(sb)) {
6043                 ext4_error(sb, "Journal got removed while the fs was mounted!");
6044                 return -EFSCORRUPTED;
6045         }
6046
6047         journal = EXT4_SB(sb)->s_journal;
6048
6049         /*
6050          * Now check for any error status which may have been recorded in the
6051          * journal by a prior ext4_error() or ext4_abort()
6052          */
6053
6054         j_errno = jbd2_journal_errno(journal);
6055         if (j_errno) {
6056                 char nbuf[16];
6057
6058                 errstr = ext4_decode_error(sb, j_errno, nbuf);
6059                 ext4_warning(sb, "Filesystem error recorded "
6060                              "from previous mount: %s", errstr);
6061                 ext4_warning(sb, "Marking fs in need of filesystem check.");
6062
6063                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6064                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6065                 ext4_commit_super(sb);
6066
6067                 jbd2_journal_clear_err(journal);
6068                 jbd2_journal_update_sb_errno(journal);
6069         }
6070         return 0;
6071 }
6072
6073 /*
6074  * Force the running and committing transactions to commit,
6075  * and wait on the commit.
6076  */
6077 int ext4_force_commit(struct super_block *sb)
6078 {
6079         journal_t *journal;
6080
6081         if (sb_rdonly(sb))
6082                 return 0;
6083
6084         journal = EXT4_SB(sb)->s_journal;
6085         return ext4_journal_force_commit(journal);
6086 }
6087
6088 static int ext4_sync_fs(struct super_block *sb, int wait)
6089 {
6090         int ret = 0;
6091         tid_t target;
6092         bool needs_barrier = false;
6093         struct ext4_sb_info *sbi = EXT4_SB(sb);
6094
6095         if (unlikely(ext4_forced_shutdown(sbi)))
6096                 return 0;
6097
6098         trace_ext4_sync_fs(sb, wait);
6099         flush_workqueue(sbi->rsv_conversion_wq);
6100         /*
6101          * Writeback quota in non-journalled quota case - journalled quota has
6102          * no dirty dquots
6103          */
6104         dquot_writeback_dquots(sb, -1);
6105         /*
6106          * Data writeback is possible w/o journal transaction, so barrier must
6107          * being sent at the end of the function. But we can skip it if
6108          * transaction_commit will do it for us.
6109          */
6110         if (sbi->s_journal) {
6111                 target = jbd2_get_latest_transaction(sbi->s_journal);
6112                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6113                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6114                         needs_barrier = true;
6115
6116                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6117                         if (wait)
6118                                 ret = jbd2_log_wait_commit(sbi->s_journal,
6119                                                            target);
6120                 }
6121         } else if (wait && test_opt(sb, BARRIER))
6122                 needs_barrier = true;
6123         if (needs_barrier) {
6124                 int err;
6125                 err = blkdev_issue_flush(sb->s_bdev);
6126                 if (!ret)
6127                         ret = err;
6128         }
6129
6130         return ret;
6131 }
6132
6133 /*
6134  * LVM calls this function before a (read-only) snapshot is created.  This
6135  * gives us a chance to flush the journal completely and mark the fs clean.
6136  *
6137  * Note that only this function cannot bring a filesystem to be in a clean
6138  * state independently. It relies on upper layer to stop all data & metadata
6139  * modifications.
6140  */
6141 static int ext4_freeze(struct super_block *sb)
6142 {
6143         int error = 0;
6144         journal_t *journal;
6145
6146         if (sb_rdonly(sb))
6147                 return 0;
6148
6149         journal = EXT4_SB(sb)->s_journal;
6150
6151         if (journal) {
6152                 /* Now we set up the journal barrier. */
6153                 jbd2_journal_lock_updates(journal);
6154
6155                 /*
6156                  * Don't clear the needs_recovery flag if we failed to
6157                  * flush the journal.
6158                  */
6159                 error = jbd2_journal_flush(journal, 0);
6160                 if (error < 0)
6161                         goto out;
6162
6163                 /* Journal blocked and flushed, clear needs_recovery flag. */
6164                 ext4_clear_feature_journal_needs_recovery(sb);
6165                 if (ext4_orphan_file_empty(sb))
6166                         ext4_clear_feature_orphan_present(sb);
6167         }
6168
6169         error = ext4_commit_super(sb);
6170 out:
6171         if (journal)
6172                 /* we rely on upper layer to stop further updates */
6173                 jbd2_journal_unlock_updates(journal);
6174         return error;
6175 }
6176
6177 /*
6178  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6179  * flag here, even though the filesystem is not technically dirty yet.
6180  */
6181 static int ext4_unfreeze(struct super_block *sb)
6182 {
6183         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
6184                 return 0;
6185
6186         if (EXT4_SB(sb)->s_journal) {
6187                 /* Reset the needs_recovery flag before the fs is unlocked. */
6188                 ext4_set_feature_journal_needs_recovery(sb);
6189                 if (ext4_has_feature_orphan_file(sb))
6190                         ext4_set_feature_orphan_present(sb);
6191         }
6192
6193         ext4_commit_super(sb);
6194         return 0;
6195 }
6196
6197 /*
6198  * Structure to save mount options for ext4_remount's benefit
6199  */
6200 struct ext4_mount_options {
6201         unsigned long s_mount_opt;
6202         unsigned long s_mount_opt2;
6203         kuid_t s_resuid;
6204         kgid_t s_resgid;
6205         unsigned long s_commit_interval;
6206         u32 s_min_batch_time, s_max_batch_time;
6207 #ifdef CONFIG_QUOTA
6208         int s_jquota_fmt;
6209         char *s_qf_names[EXT4_MAXQUOTAS];
6210 #endif
6211 };
6212
6213 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6214 {
6215         struct ext4_fs_context *ctx = fc->fs_private;
6216         struct ext4_super_block *es;
6217         struct ext4_sb_info *sbi = EXT4_SB(sb);
6218         unsigned long old_sb_flags;
6219         struct ext4_mount_options old_opts;
6220         ext4_group_t g;
6221         int err = 0;
6222 #ifdef CONFIG_QUOTA
6223         int enable_quota = 0;
6224         int i, j;
6225         char *to_free[EXT4_MAXQUOTAS];
6226 #endif
6227
6228         ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
6229
6230         /* Store the original options */
6231         old_sb_flags = sb->s_flags;
6232         old_opts.s_mount_opt = sbi->s_mount_opt;
6233         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6234         old_opts.s_resuid = sbi->s_resuid;
6235         old_opts.s_resgid = sbi->s_resgid;
6236         old_opts.s_commit_interval = sbi->s_commit_interval;
6237         old_opts.s_min_batch_time = sbi->s_min_batch_time;
6238         old_opts.s_max_batch_time = sbi->s_max_batch_time;
6239 #ifdef CONFIG_QUOTA
6240         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6241         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6242                 if (sbi->s_qf_names[i]) {
6243                         char *qf_name = get_qf_name(sb, sbi, i);
6244
6245                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6246                         if (!old_opts.s_qf_names[i]) {
6247                                 for (j = 0; j < i; j++)
6248                                         kfree(old_opts.s_qf_names[j]);
6249                                 return -ENOMEM;
6250                         }
6251                 } else
6252                         old_opts.s_qf_names[i] = NULL;
6253 #endif
6254         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6255                 ctx->journal_ioprio =
6256                         sbi->s_journal->j_task->io_context->ioprio;
6257
6258         ext4_apply_options(fc, sb);
6259
6260         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6261             test_opt(sb, JOURNAL_CHECKSUM)) {
6262                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6263                          "during remount not supported; ignoring");
6264                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6265         }
6266
6267         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6268                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6269                         ext4_msg(sb, KERN_ERR, "can't mount with "
6270                                  "both data=journal and delalloc");
6271                         err = -EINVAL;
6272                         goto restore_opts;
6273                 }
6274                 if (test_opt(sb, DIOREAD_NOLOCK)) {
6275                         ext4_msg(sb, KERN_ERR, "can't mount with "
6276                                  "both data=journal and dioread_nolock");
6277                         err = -EINVAL;
6278                         goto restore_opts;
6279                 }
6280         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6281                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6282                         ext4_msg(sb, KERN_ERR, "can't mount with "
6283                                 "journal_async_commit in data=ordered mode");
6284                         err = -EINVAL;
6285                         goto restore_opts;
6286                 }
6287         }
6288
6289         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6290                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6291                 err = -EINVAL;
6292                 goto restore_opts;
6293         }
6294
6295         if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
6296                 ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6297
6298         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6299                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6300
6301         es = sbi->s_es;
6302
6303         if (sbi->s_journal) {
6304                 ext4_init_journal_params(sb, sbi->s_journal);
6305                 set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6306         }
6307
6308         /* Flush outstanding errors before changing fs state */
6309         flush_work(&sbi->s_error_work);
6310
6311         if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6312                 if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
6313                         err = -EROFS;
6314                         goto restore_opts;
6315                 }
6316
6317                 if (fc->sb_flags & SB_RDONLY) {
6318                         err = sync_filesystem(sb);
6319                         if (err < 0)
6320                                 goto restore_opts;
6321                         err = dquot_suspend(sb, -1);
6322                         if (err < 0)
6323                                 goto restore_opts;
6324
6325                         /*
6326                          * First of all, the unconditional stuff we have to do
6327                          * to disable replay of the journal when we next remount
6328                          */
6329                         sb->s_flags |= SB_RDONLY;
6330
6331                         /*
6332                          * OK, test if we are remounting a valid rw partition
6333                          * readonly, and if so set the rdonly flag and then
6334                          * mark the partition as valid again.
6335                          */
6336                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6337                             (sbi->s_mount_state & EXT4_VALID_FS))
6338                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
6339
6340                         if (sbi->s_journal) {
6341                                 /*
6342                                  * We let remount-ro finish even if marking fs
6343                                  * as clean failed...
6344                                  */
6345                                 ext4_mark_recovery_complete(sb, es);
6346                         }
6347                 } else {
6348                         /* Make sure we can mount this feature set readwrite */
6349                         if (ext4_has_feature_readonly(sb) ||
6350                             !ext4_feature_set_ok(sb, 0)) {
6351                                 err = -EROFS;
6352                                 goto restore_opts;
6353                         }
6354                         /*
6355                          * Make sure the group descriptor checksums
6356                          * are sane.  If they aren't, refuse to remount r/w.
6357                          */
6358                         for (g = 0; g < sbi->s_groups_count; g++) {
6359                                 struct ext4_group_desc *gdp =
6360                                         ext4_get_group_desc(sb, g, NULL);
6361
6362                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6363                                         ext4_msg(sb, KERN_ERR,
6364                "ext4_remount: Checksum for group %u failed (%u!=%u)",
6365                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6366                                                le16_to_cpu(gdp->bg_checksum));
6367                                         err = -EFSBADCRC;
6368                                         goto restore_opts;
6369                                 }
6370                         }
6371
6372                         /*
6373                          * If we have an unprocessed orphan list hanging
6374                          * around from a previously readonly bdev mount,
6375                          * require a full umount/remount for now.
6376                          */
6377                         if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6378                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
6379                                        "remount RDWR because of unprocessed "
6380                                        "orphan inode list.  Please "
6381                                        "umount/remount instead");
6382                                 err = -EINVAL;
6383                                 goto restore_opts;
6384                         }
6385
6386                         /*
6387                          * Mounting a RDONLY partition read-write, so reread
6388                          * and store the current valid flag.  (It may have
6389                          * been changed by e2fsck since we originally mounted
6390                          * the partition.)
6391                          */
6392                         if (sbi->s_journal) {
6393                                 err = ext4_clear_journal_err(sb, es);
6394                                 if (err)
6395                                         goto restore_opts;
6396                         }
6397                         sbi->s_mount_state = le16_to_cpu(es->s_state);
6398
6399                         err = ext4_setup_super(sb, es, 0);
6400                         if (err)
6401                                 goto restore_opts;
6402
6403                         sb->s_flags &= ~SB_RDONLY;
6404                         if (ext4_has_feature_mmp(sb))
6405                                 if (ext4_multi_mount_protect(sb,
6406                                                 le64_to_cpu(es->s_mmp_block))) {
6407                                         err = -EROFS;
6408                                         goto restore_opts;
6409                                 }
6410 #ifdef CONFIG_QUOTA
6411                         enable_quota = 1;
6412 #endif
6413                 }
6414         }
6415
6416         /*
6417          * Reinitialize lazy itable initialization thread based on
6418          * current settings
6419          */
6420         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6421                 ext4_unregister_li_request(sb);
6422         else {
6423                 ext4_group_t first_not_zeroed;
6424                 first_not_zeroed = ext4_has_uninit_itable(sb);
6425                 ext4_register_li_request(sb, first_not_zeroed);
6426         }
6427
6428         /*
6429          * Handle creation of system zone data early because it can fail.
6430          * Releasing of existing data is done when we are sure remount will
6431          * succeed.
6432          */
6433         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6434                 err = ext4_setup_system_zone(sb);
6435                 if (err)
6436                         goto restore_opts;
6437         }
6438
6439         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6440                 err = ext4_commit_super(sb);
6441                 if (err)
6442                         goto restore_opts;
6443         }
6444
6445 #ifdef CONFIG_QUOTA
6446         /* Release old quota file names */
6447         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6448                 kfree(old_opts.s_qf_names[i]);
6449         if (enable_quota) {
6450                 if (sb_any_quota_suspended(sb))
6451                         dquot_resume(sb, -1);
6452                 else if (ext4_has_feature_quota(sb)) {
6453                         err = ext4_enable_quotas(sb);
6454                         if (err)
6455                                 goto restore_opts;
6456                 }
6457         }
6458 #endif
6459         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6460                 ext4_release_system_zone(sb);
6461
6462         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6463                 ext4_stop_mmpd(sbi);
6464
6465         return 0;
6466
6467 restore_opts:
6468         sb->s_flags = old_sb_flags;
6469         sbi->s_mount_opt = old_opts.s_mount_opt;
6470         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6471         sbi->s_resuid = old_opts.s_resuid;
6472         sbi->s_resgid = old_opts.s_resgid;
6473         sbi->s_commit_interval = old_opts.s_commit_interval;
6474         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6475         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6476         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6477                 ext4_release_system_zone(sb);
6478 #ifdef CONFIG_QUOTA
6479         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6480         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6481                 to_free[i] = get_qf_name(sb, sbi, i);
6482                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6483         }
6484         synchronize_rcu();
6485         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6486                 kfree(to_free[i]);
6487 #endif
6488         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6489                 ext4_stop_mmpd(sbi);
6490         return err;
6491 }
6492
6493 static int ext4_reconfigure(struct fs_context *fc)
6494 {
6495         struct super_block *sb = fc->root->d_sb;
6496         int ret;
6497
6498         fc->s_fs_info = EXT4_SB(sb);
6499
6500         ret = ext4_check_opt_consistency(fc, sb);
6501         if (ret < 0)
6502                 return ret;
6503
6504         ret = __ext4_remount(fc, sb);
6505         if (ret < 0)
6506                 return ret;
6507
6508         ext4_msg(sb, KERN_INFO, "re-mounted. Quota mode: %s.",
6509                  ext4_quota_mode(sb));
6510
6511         return 0;
6512 }
6513
6514 #ifdef CONFIG_QUOTA
6515 static int ext4_statfs_project(struct super_block *sb,
6516                                kprojid_t projid, struct kstatfs *buf)
6517 {
6518         struct kqid qid;
6519         struct dquot *dquot;
6520         u64 limit;
6521         u64 curblock;
6522
6523         qid = make_kqid_projid(projid);
6524         dquot = dqget(sb, qid);
6525         if (IS_ERR(dquot))
6526                 return PTR_ERR(dquot);
6527         spin_lock(&dquot->dq_dqb_lock);
6528
6529         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6530                              dquot->dq_dqb.dqb_bhardlimit);
6531         limit >>= sb->s_blocksize_bits;
6532
6533         if (limit && buf->f_blocks > limit) {
6534                 curblock = (dquot->dq_dqb.dqb_curspace +
6535                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6536                 buf->f_blocks = limit;
6537                 buf->f_bfree = buf->f_bavail =
6538                         (buf->f_blocks > curblock) ?
6539                          (buf->f_blocks - curblock) : 0;
6540         }
6541
6542         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6543                              dquot->dq_dqb.dqb_ihardlimit);
6544         if (limit && buf->f_files > limit) {
6545                 buf->f_files = limit;
6546                 buf->f_ffree =
6547                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6548                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6549         }
6550
6551         spin_unlock(&dquot->dq_dqb_lock);
6552         dqput(dquot);
6553         return 0;
6554 }
6555 #endif
6556
6557 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6558 {
6559         struct super_block *sb = dentry->d_sb;
6560         struct ext4_sb_info *sbi = EXT4_SB(sb);
6561         struct ext4_super_block *es = sbi->s_es;
6562         ext4_fsblk_t overhead = 0, resv_blocks;
6563         s64 bfree;
6564         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6565
6566         if (!test_opt(sb, MINIX_DF))
6567                 overhead = sbi->s_overhead;
6568
6569         buf->f_type = EXT4_SUPER_MAGIC;
6570         buf->f_bsize = sb->s_blocksize;
6571         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6572         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6573                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6574         /* prevent underflow in case that few free space is available */
6575         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6576         buf->f_bavail = buf->f_bfree -
6577                         (ext4_r_blocks_count(es) + resv_blocks);
6578         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6579                 buf->f_bavail = 0;
6580         buf->f_files = le32_to_cpu(es->s_inodes_count);
6581         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6582         buf->f_namelen = EXT4_NAME_LEN;
6583         buf->f_fsid = uuid_to_fsid(es->s_uuid);
6584
6585 #ifdef CONFIG_QUOTA
6586         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6587             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6588                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6589 #endif
6590         return 0;
6591 }
6592
6593
6594 #ifdef CONFIG_QUOTA
6595
6596 /*
6597  * Helper functions so that transaction is started before we acquire dqio_sem
6598  * to keep correct lock ordering of transaction > dqio_sem
6599  */
6600 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6601 {
6602         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6603 }
6604
6605 static int ext4_write_dquot(struct dquot *dquot)
6606 {
6607         int ret, err;
6608         handle_t *handle;
6609         struct inode *inode;
6610
6611         inode = dquot_to_inode(dquot);
6612         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6613                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6614         if (IS_ERR(handle))
6615                 return PTR_ERR(handle);
6616         ret = dquot_commit(dquot);
6617         err = ext4_journal_stop(handle);
6618         if (!ret)
6619                 ret = err;
6620         return ret;
6621 }
6622
6623 static int ext4_acquire_dquot(struct dquot *dquot)
6624 {
6625         int ret, err;
6626         handle_t *handle;
6627
6628         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6629                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6630         if (IS_ERR(handle))
6631                 return PTR_ERR(handle);
6632         ret = dquot_acquire(dquot);
6633         err = ext4_journal_stop(handle);
6634         if (!ret)
6635                 ret = err;
6636         return ret;
6637 }
6638
6639 static int ext4_release_dquot(struct dquot *dquot)
6640 {
6641         int ret, err;
6642         handle_t *handle;
6643
6644         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6645                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6646         if (IS_ERR(handle)) {
6647                 /* Release dquot anyway to avoid endless cycle in dqput() */
6648                 dquot_release(dquot);
6649                 return PTR_ERR(handle);
6650         }
6651         ret = dquot_release(dquot);
6652         err = ext4_journal_stop(handle);
6653         if (!ret)
6654                 ret = err;
6655         return ret;
6656 }
6657
6658 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6659 {
6660         struct super_block *sb = dquot->dq_sb;
6661
6662         if (ext4_is_quota_journalled(sb)) {
6663                 dquot_mark_dquot_dirty(dquot);
6664                 return ext4_write_dquot(dquot);
6665         } else {
6666                 return dquot_mark_dquot_dirty(dquot);
6667         }
6668 }
6669
6670 static int ext4_write_info(struct super_block *sb, int type)
6671 {
6672         int ret, err;
6673         handle_t *handle;
6674
6675         /* Data block + inode block */
6676         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6677         if (IS_ERR(handle))
6678                 return PTR_ERR(handle);
6679         ret = dquot_commit_info(sb, type);
6680         err = ext4_journal_stop(handle);
6681         if (!ret)
6682                 ret = err;
6683         return ret;
6684 }
6685
6686 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6687 {
6688         struct ext4_inode_info *ei = EXT4_I(inode);
6689
6690         /* The first argument of lockdep_set_subclass has to be
6691          * *exactly* the same as the argument to init_rwsem() --- in
6692          * this case, in init_once() --- or lockdep gets unhappy
6693          * because the name of the lock is set using the
6694          * stringification of the argument to init_rwsem().
6695          */
6696         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6697         lockdep_set_subclass(&ei->i_data_sem, subclass);
6698 }
6699
6700 /*
6701  * Standard function to be called on quota_on
6702  */
6703 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6704                          const struct path *path)
6705 {
6706         int err;
6707
6708         if (!test_opt(sb, QUOTA))
6709                 return -EINVAL;
6710
6711         /* Quotafile not on the same filesystem? */
6712         if (path->dentry->d_sb != sb)
6713                 return -EXDEV;
6714
6715         /* Quota already enabled for this file? */
6716         if (IS_NOQUOTA(d_inode(path->dentry)))
6717                 return -EBUSY;
6718
6719         /* Journaling quota? */
6720         if (EXT4_SB(sb)->s_qf_names[type]) {
6721                 /* Quotafile not in fs root? */
6722                 if (path->dentry->d_parent != sb->s_root)
6723                         ext4_msg(sb, KERN_WARNING,
6724                                 "Quota file not on filesystem root. "
6725                                 "Journaled quota will not work");
6726                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6727         } else {
6728                 /*
6729                  * Clear the flag just in case mount options changed since
6730                  * last time.
6731                  */
6732                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6733         }
6734
6735         /*
6736          * When we journal data on quota file, we have to flush journal to see
6737          * all updates to the file when we bypass pagecache...
6738          */
6739         if (EXT4_SB(sb)->s_journal &&
6740             ext4_should_journal_data(d_inode(path->dentry))) {
6741                 /*
6742                  * We don't need to lock updates but journal_flush() could
6743                  * otherwise be livelocked...
6744                  */
6745                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6746                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal, 0);
6747                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6748                 if (err)
6749                         return err;
6750         }
6751
6752         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6753         err = dquot_quota_on(sb, type, format_id, path);
6754         if (!err) {
6755                 struct inode *inode = d_inode(path->dentry);
6756                 handle_t *handle;
6757
6758                 /*
6759                  * Set inode flags to prevent userspace from messing with quota
6760                  * files. If this fails, we return success anyway since quotas
6761                  * are already enabled and this is not a hard failure.
6762                  */
6763                 inode_lock(inode);
6764                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6765                 if (IS_ERR(handle))
6766                         goto unlock_inode;
6767                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6768                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6769                                 S_NOATIME | S_IMMUTABLE);
6770                 err = ext4_mark_inode_dirty(handle, inode);
6771                 ext4_journal_stop(handle);
6772         unlock_inode:
6773                 inode_unlock(inode);
6774                 if (err)
6775                         dquot_quota_off(sb, type);
6776         }
6777         if (err)
6778                 lockdep_set_quota_inode(path->dentry->d_inode,
6779                                              I_DATA_SEM_NORMAL);
6780         return err;
6781 }
6782
6783 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6784                              unsigned int flags)
6785 {
6786         int err;
6787         struct inode *qf_inode;
6788         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6789                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6790                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6791                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6792         };
6793
6794         BUG_ON(!ext4_has_feature_quota(sb));
6795
6796         if (!qf_inums[type])
6797                 return -EPERM;
6798
6799         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6800         if (IS_ERR(qf_inode)) {
6801                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6802                 return PTR_ERR(qf_inode);
6803         }
6804
6805         /* Don't account quota for quota files to avoid recursion */
6806         qf_inode->i_flags |= S_NOQUOTA;
6807         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6808         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6809         if (err)
6810                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6811         iput(qf_inode);
6812
6813         return err;
6814 }
6815
6816 /* Enable usage tracking for all quota types. */
6817 int ext4_enable_quotas(struct super_block *sb)
6818 {
6819         int type, err = 0;
6820         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6821                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6822                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6823                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6824         };
6825         bool quota_mopt[EXT4_MAXQUOTAS] = {
6826                 test_opt(sb, USRQUOTA),
6827                 test_opt(sb, GRPQUOTA),
6828                 test_opt(sb, PRJQUOTA),
6829         };
6830
6831         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6832         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6833                 if (qf_inums[type]) {
6834                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6835                                 DQUOT_USAGE_ENABLED |
6836                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6837                         if (err) {
6838                                 ext4_warning(sb,
6839                                         "Failed to enable quota tracking "
6840                                         "(type=%d, err=%d). Please run "
6841                                         "e2fsck to fix.", type, err);
6842                                 for (type--; type >= 0; type--) {
6843                                         struct inode *inode;
6844
6845                                         inode = sb_dqopt(sb)->files[type];
6846                                         if (inode)
6847                                                 inode = igrab(inode);
6848                                         dquot_quota_off(sb, type);
6849                                         if (inode) {
6850                                                 lockdep_set_quota_inode(inode,
6851                                                         I_DATA_SEM_NORMAL);
6852                                                 iput(inode);
6853                                         }
6854                                 }
6855
6856                                 return err;
6857                         }
6858                 }
6859         }
6860         return 0;
6861 }
6862
6863 static int ext4_quota_off(struct super_block *sb, int type)
6864 {
6865         struct inode *inode = sb_dqopt(sb)->files[type];
6866         handle_t *handle;
6867         int err;
6868
6869         /* Force all delayed allocation blocks to be allocated.
6870          * Caller already holds s_umount sem */
6871         if (test_opt(sb, DELALLOC))
6872                 sync_filesystem(sb);
6873
6874         if (!inode || !igrab(inode))
6875                 goto out;
6876
6877         err = dquot_quota_off(sb, type);
6878         if (err || ext4_has_feature_quota(sb))
6879                 goto out_put;
6880
6881         inode_lock(inode);
6882         /*
6883          * Update modification times of quota files when userspace can
6884          * start looking at them. If we fail, we return success anyway since
6885          * this is not a hard failure and quotas are already disabled.
6886          */
6887         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6888         if (IS_ERR(handle)) {
6889                 err = PTR_ERR(handle);
6890                 goto out_unlock;
6891         }
6892         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6893         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6894         inode->i_mtime = inode->i_ctime = current_time(inode);
6895         err = ext4_mark_inode_dirty(handle, inode);
6896         ext4_journal_stop(handle);
6897 out_unlock:
6898         inode_unlock(inode);
6899 out_put:
6900         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6901         iput(inode);
6902         return err;
6903 out:
6904         return dquot_quota_off(sb, type);
6905 }
6906
6907 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6908  * acquiring the locks... As quota files are never truncated and quota code
6909  * itself serializes the operations (and no one else should touch the files)
6910  * we don't have to be afraid of races */
6911 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6912                                size_t len, loff_t off)
6913 {
6914         struct inode *inode = sb_dqopt(sb)->files[type];
6915         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6916         int offset = off & (sb->s_blocksize - 1);
6917         int tocopy;
6918         size_t toread;
6919         struct buffer_head *bh;
6920         loff_t i_size = i_size_read(inode);
6921
6922         if (off > i_size)
6923                 return 0;
6924         if (off+len > i_size)
6925                 len = i_size-off;
6926         toread = len;
6927         while (toread > 0) {
6928                 tocopy = sb->s_blocksize - offset < toread ?
6929                                 sb->s_blocksize - offset : toread;
6930                 bh = ext4_bread(NULL, inode, blk, 0);
6931                 if (IS_ERR(bh))
6932                         return PTR_ERR(bh);
6933                 if (!bh)        /* A hole? */
6934                         memset(data, 0, tocopy);
6935                 else
6936                         memcpy(data, bh->b_data+offset, tocopy);
6937                 brelse(bh);
6938                 offset = 0;
6939                 toread -= tocopy;
6940                 data += tocopy;
6941                 blk++;
6942         }
6943         return len;
6944 }
6945
6946 /* Write to quotafile (we know the transaction is already started and has
6947  * enough credits) */
6948 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6949                                 const char *data, size_t len, loff_t off)
6950 {
6951         struct inode *inode = sb_dqopt(sb)->files[type];
6952         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6953         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6954         int retries = 0;
6955         struct buffer_head *bh;
6956         handle_t *handle = journal_current_handle();
6957
6958         if (!handle) {
6959                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6960                         " cancelled because transaction is not started",
6961                         (unsigned long long)off, (unsigned long long)len);
6962                 return -EIO;
6963         }
6964         /*
6965          * Since we account only one data block in transaction credits,
6966          * then it is impossible to cross a block boundary.
6967          */
6968         if (sb->s_blocksize - offset < len) {
6969                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6970                         " cancelled because not block aligned",
6971                         (unsigned long long)off, (unsigned long long)len);
6972                 return -EIO;
6973         }
6974
6975         do {
6976                 bh = ext4_bread(handle, inode, blk,
6977                                 EXT4_GET_BLOCKS_CREATE |
6978                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6979         } while (PTR_ERR(bh) == -ENOSPC &&
6980                  ext4_should_retry_alloc(inode->i_sb, &retries));
6981         if (IS_ERR(bh))
6982                 return PTR_ERR(bh);
6983         if (!bh)
6984                 goto out;
6985         BUFFER_TRACE(bh, "get write access");
6986         err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
6987         if (err) {
6988                 brelse(bh);
6989                 return err;
6990         }
6991         lock_buffer(bh);
6992         memcpy(bh->b_data+offset, data, len);
6993         flush_dcache_page(bh->b_page);
6994         unlock_buffer(bh);
6995         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6996         brelse(bh);
6997 out:
6998         if (inode->i_size < off + len) {
6999                 i_size_write(inode, off + len);
7000                 EXT4_I(inode)->i_disksize = inode->i_size;
7001                 err2 = ext4_mark_inode_dirty(handle, inode);
7002                 if (unlikely(err2 && !err))
7003                         err = err2;
7004         }
7005         return err ? err : len;
7006 }
7007 #endif
7008
7009 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
7010 static inline void register_as_ext2(void)
7011 {
7012         int err = register_filesystem(&ext2_fs_type);
7013         if (err)
7014                 printk(KERN_WARNING
7015                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7016 }
7017
7018 static inline void unregister_as_ext2(void)
7019 {
7020         unregister_filesystem(&ext2_fs_type);
7021 }
7022
7023 static inline int ext2_feature_set_ok(struct super_block *sb)
7024 {
7025         if (ext4_has_unknown_ext2_incompat_features(sb))
7026                 return 0;
7027         if (sb_rdonly(sb))
7028                 return 1;
7029         if (ext4_has_unknown_ext2_ro_compat_features(sb))
7030                 return 0;
7031         return 1;
7032 }
7033 #else
7034 static inline void register_as_ext2(void) { }
7035 static inline void unregister_as_ext2(void) { }
7036 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7037 #endif
7038
7039 static inline void register_as_ext3(void)
7040 {
7041         int err = register_filesystem(&ext3_fs_type);
7042         if (err)
7043                 printk(KERN_WARNING
7044                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7045 }
7046
7047 static inline void unregister_as_ext3(void)
7048 {
7049         unregister_filesystem(&ext3_fs_type);
7050 }
7051
7052 static inline int ext3_feature_set_ok(struct super_block *sb)
7053 {
7054         if (ext4_has_unknown_ext3_incompat_features(sb))
7055                 return 0;
7056         if (!ext4_has_feature_journal(sb))
7057                 return 0;
7058         if (sb_rdonly(sb))
7059                 return 1;
7060         if (ext4_has_unknown_ext3_ro_compat_features(sb))
7061                 return 0;
7062         return 1;
7063 }
7064
7065 static struct file_system_type ext4_fs_type = {
7066         .owner                  = THIS_MODULE,
7067         .name                   = "ext4",
7068         .init_fs_context        = ext4_init_fs_context,
7069         .parameters             = ext4_param_specs,
7070         .kill_sb                = kill_block_super,
7071         .fs_flags               = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
7072 };
7073 MODULE_ALIAS_FS("ext4");
7074
7075 /* Shared across all ext4 file systems */
7076 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
7077
7078 static int __init ext4_init_fs(void)
7079 {
7080         int i, err;
7081
7082         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7083         ext4_li_info = NULL;
7084
7085         /* Build-time check for flags consistency */
7086         ext4_check_flag_values();
7087
7088         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
7089                 init_waitqueue_head(&ext4__ioend_wq[i]);
7090
7091         err = ext4_init_es();
7092         if (err)
7093                 return err;
7094
7095         err = ext4_init_pending();
7096         if (err)
7097                 goto out7;
7098
7099         err = ext4_init_post_read_processing();
7100         if (err)
7101                 goto out6;
7102
7103         err = ext4_init_pageio();
7104         if (err)
7105                 goto out5;
7106
7107         err = ext4_init_system_zone();
7108         if (err)
7109                 goto out4;
7110
7111         err = ext4_init_sysfs();
7112         if (err)
7113                 goto out3;
7114
7115         err = ext4_init_mballoc();
7116         if (err)
7117                 goto out2;
7118         err = init_inodecache();
7119         if (err)
7120                 goto out1;
7121
7122         err = ext4_fc_init_dentry_cache();
7123         if (err)
7124                 goto out05;
7125
7126         register_as_ext3();
7127         register_as_ext2();
7128         err = register_filesystem(&ext4_fs_type);
7129         if (err)
7130                 goto out;
7131
7132         return 0;
7133 out:
7134         unregister_as_ext2();
7135         unregister_as_ext3();
7136         ext4_fc_destroy_dentry_cache();
7137 out05:
7138         destroy_inodecache();
7139 out1:
7140         ext4_exit_mballoc();
7141 out2:
7142         ext4_exit_sysfs();
7143 out3:
7144         ext4_exit_system_zone();
7145 out4:
7146         ext4_exit_pageio();
7147 out5:
7148         ext4_exit_post_read_processing();
7149 out6:
7150         ext4_exit_pending();
7151 out7:
7152         ext4_exit_es();
7153
7154         return err;
7155 }
7156
7157 static void __exit ext4_exit_fs(void)
7158 {
7159         ext4_destroy_lazyinit_thread();
7160         unregister_as_ext2();
7161         unregister_as_ext3();
7162         unregister_filesystem(&ext4_fs_type);
7163         ext4_fc_destroy_dentry_cache();
7164         destroy_inodecache();
7165         ext4_exit_mballoc();
7166         ext4_exit_sysfs();
7167         ext4_exit_system_zone();
7168         ext4_exit_pageio();
7169         ext4_exit_post_read_processing();
7170         ext4_exit_es();
7171         ext4_exit_pending();
7172 }
7173
7174 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7175 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7176 MODULE_LICENSE("GPL");
7177 MODULE_SOFTDEP("pre: crc32c");
7178 module_init(ext4_init_fs)
7179 module_exit(ext4_exit_fs)