2 * linux/fs/ext4/ialloc.c
4 * Copyright (C) 1992, 1993, 1994, 1995
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
9 * BSD ufs-inspired inode and directory allocation by
11 * Big-endian to little-endian byte-swapping/bitmaps by
15 #include <linux/time.h>
17 #include <linux/jbd2.h>
18 #include <linux/stat.h>
19 #include <linux/string.h>
20 #include <linux/quotaops.h>
21 #include <linux/buffer_head.h>
22 #include <linux/random.h>
23 #include <linux/bitops.h>
24 #include <linux/blkdev.h>
25 #include <asm/byteorder.h>
28 #include "ext4_jbd2.h"
32 #include <trace/events/ext4.h>
35 * ialloc.c contains the inodes allocation and deallocation routines
39 * The free inodes are managed by bitmaps. A file system contains several
40 * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
41 * block for inodes, N blocks for the inode table and data blocks.
43 * The file system contains group descriptors which are located after the
44 * super block. Each descriptor contains the number of the bitmap block and
45 * the free blocks count in the block.
49 * To avoid calling the atomic setbit hundreds or thousands of times, we only
50 * need to use it within a single byte (to ensure we get endianness right).
51 * We can use memset for the rest of the bitmap as there are no other users.
53 void mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
57 if (start_bit >= end_bit)
60 ext4_debug("mark end bits +%d through +%d used\n", start_bit, end_bit);
61 for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
62 ext4_set_bit(i, bitmap);
64 memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3);
67 /* Initializes an uninitialized inode bitmap */
68 unsigned ext4_init_inode_bitmap(struct super_block *sb, struct buffer_head *bh,
69 ext4_group_t block_group,
70 struct ext4_group_desc *gdp)
72 struct ext4_sb_info *sbi = EXT4_SB(sb);
74 J_ASSERT_BH(bh, buffer_locked(bh));
76 /* If checksum is bad mark all blocks and inodes use to prevent
77 * allocation, essentially implementing a per-group read-only flag. */
78 if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) {
79 ext4_error(sb, __func__, "Checksum bad for group %u",
81 ext4_free_blks_set(sb, gdp, 0);
82 ext4_free_inodes_set(sb, gdp, 0);
83 ext4_itable_unused_set(sb, gdp, 0);
84 memset(bh->b_data, 0xff, sb->s_blocksize);
88 memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8);
89 mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), sb->s_blocksize * 8,
92 return EXT4_INODES_PER_GROUP(sb);
96 * Read the inode allocation bitmap for a given block_group, reading
97 * into the specified slot in the superblock's bitmap cache.
99 * Return buffer_head of bitmap on success or NULL.
101 static struct buffer_head *
102 ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
104 struct ext4_group_desc *desc;
105 struct buffer_head *bh = NULL;
106 ext4_fsblk_t bitmap_blk;
108 desc = ext4_get_group_desc(sb, block_group, NULL);
111 bitmap_blk = ext4_inode_bitmap(sb, desc);
112 bh = sb_getblk(sb, bitmap_blk);
114 ext4_error(sb, __func__,
115 "Cannot read inode bitmap - "
116 "block_group = %u, inode_bitmap = %llu",
117 block_group, bitmap_blk);
120 if (bitmap_uptodate(bh))
124 if (bitmap_uptodate(bh)) {
128 ext4_lock_group(sb, block_group);
129 if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
130 ext4_init_inode_bitmap(sb, bh, block_group, desc);
131 set_bitmap_uptodate(bh);
132 set_buffer_uptodate(bh);
133 ext4_unlock_group(sb, block_group);
137 ext4_unlock_group(sb, block_group);
138 if (buffer_uptodate(bh)) {
140 * if not uninit if bh is uptodate,
141 * bitmap is also uptodate
143 set_bitmap_uptodate(bh);
148 * submit the buffer_head for read. We can
149 * safely mark the bitmap as uptodate now.
150 * We do it here so the bitmap uptodate bit
151 * get set with buffer lock held.
153 set_bitmap_uptodate(bh);
154 if (bh_submit_read(bh) < 0) {
156 ext4_error(sb, __func__,
157 "Cannot read inode bitmap - "
158 "block_group = %u, inode_bitmap = %llu",
159 block_group, bitmap_blk);
166 * NOTE! When we get the inode, we're the only people
167 * that have access to it, and as such there are no
168 * race conditions we have to worry about. The inode
169 * is not on the hash-lists, and it cannot be reached
170 * through the filesystem because the directory entry
171 * has been deleted earlier.
173 * HOWEVER: we must make sure that we get no aliases,
174 * which means that we have to call "clear_inode()"
175 * _before_ we mark the inode not in use in the inode
176 * bitmaps. Otherwise a newly created file might use
177 * the same inode number (not actually the same pointer
178 * though), and then we'd have two inodes sharing the
179 * same inode number and space on the harddisk.
181 void ext4_free_inode(handle_t *handle, struct inode *inode)
183 struct super_block *sb = inode->i_sb;
186 struct buffer_head *bitmap_bh = NULL;
187 struct buffer_head *bh2;
188 ext4_group_t block_group;
190 struct ext4_group_desc *gdp;
191 struct ext4_super_block *es;
192 struct ext4_sb_info *sbi;
193 int fatal = 0, err, count, cleared;
195 if (atomic_read(&inode->i_count) > 1) {
196 printk(KERN_ERR "ext4_free_inode: inode has count=%d\n",
197 atomic_read(&inode->i_count));
200 if (inode->i_nlink) {
201 printk(KERN_ERR "ext4_free_inode: inode has nlink=%d\n",
206 printk(KERN_ERR "ext4_free_inode: inode on "
207 "nonexistent device\n");
213 ext4_debug("freeing inode %lu\n", ino);
214 trace_ext4_free_inode(inode);
217 * Note: we must free any quota before locking the superblock,
218 * as writing the quota to disk may need the lock as well.
221 ext4_xattr_delete_inode(handle, inode);
222 vfs_dq_free_inode(inode);
225 is_directory = S_ISDIR(inode->i_mode);
227 /* Do this BEFORE marking the inode not in use or returning an error */
230 es = EXT4_SB(sb)->s_es;
231 if (ino < EXT4_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
232 ext4_error(sb, "ext4_free_inode",
233 "reserved or nonexistent inode %lu", ino);
236 block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
237 bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
238 bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
242 BUFFER_TRACE(bitmap_bh, "get_write_access");
243 fatal = ext4_journal_get_write_access(handle, bitmap_bh);
247 /* Ok, now we can actually update the inode bitmaps.. */
248 cleared = ext4_clear_bit_atomic(ext4_group_lock_ptr(sb, block_group),
249 bit, bitmap_bh->b_data);
251 ext4_error(sb, "ext4_free_inode",
252 "bit already cleared for inode %lu", ino);
254 gdp = ext4_get_group_desc(sb, block_group, &bh2);
256 BUFFER_TRACE(bh2, "get_write_access");
257 fatal = ext4_journal_get_write_access(handle, bh2);
258 if (fatal) goto error_return;
261 ext4_lock_group(sb, block_group);
262 count = ext4_free_inodes_count(sb, gdp) + 1;
263 ext4_free_inodes_set(sb, gdp, count);
265 count = ext4_used_dirs_count(sb, gdp) - 1;
266 ext4_used_dirs_set(sb, gdp, count);
267 if (sbi->s_log_groups_per_flex) {
270 f = ext4_flex_group(sbi, block_group);
271 atomic_dec(&sbi->s_flex_groups[f].free_inodes);
275 gdp->bg_checksum = ext4_group_desc_csum(sbi,
277 ext4_unlock_group(sb, block_group);
278 percpu_counter_inc(&sbi->s_freeinodes_counter);
280 percpu_counter_dec(&sbi->s_dirs_counter);
282 if (sbi->s_log_groups_per_flex) {
285 f = ext4_flex_group(sbi, block_group);
286 atomic_inc(&sbi->s_flex_groups[f].free_inodes);
289 BUFFER_TRACE(bh2, "call ext4_handle_dirty_metadata");
290 err = ext4_handle_dirty_metadata(handle, NULL, bh2);
291 if (!fatal) fatal = err;
293 BUFFER_TRACE(bitmap_bh, "call ext4_handle_dirty_metadata");
294 err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh);
300 ext4_std_error(sb, fatal);
304 * There are two policies for allocating an inode. If the new inode is
305 * a directory, then a forward search is made for a block group with both
306 * free space and a low directory-to-inode ratio; if that fails, then of
307 * the groups with above-average free space, that group with the fewest
308 * directories already is chosen.
310 * For other inodes, search forward from the parent directory\'s block
311 * group to find a free inode.
313 static int find_group_dir(struct super_block *sb, struct inode *parent,
314 ext4_group_t *best_group)
316 ext4_group_t ngroups = ext4_get_groups_count(sb);
317 unsigned int freei, avefreei;
318 struct ext4_group_desc *desc, *best_desc = NULL;
322 freei = percpu_counter_read_positive(&EXT4_SB(sb)->s_freeinodes_counter);
323 avefreei = freei / ngroups;
325 for (group = 0; group < ngroups; group++) {
326 desc = ext4_get_group_desc(sb, group, NULL);
327 if (!desc || !ext4_free_inodes_count(sb, desc))
329 if (ext4_free_inodes_count(sb, desc) < avefreei)
332 (ext4_free_blks_count(sb, desc) >
333 ext4_free_blks_count(sb, best_desc))) {
342 #define free_block_ratio 10
344 static int find_group_flex(struct super_block *sb, struct inode *parent,
345 ext4_group_t *best_group)
347 struct ext4_sb_info *sbi = EXT4_SB(sb);
348 struct ext4_group_desc *desc;
349 struct flex_groups *flex_group = sbi->s_flex_groups;
350 ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
351 ext4_group_t parent_fbg_group = ext4_flex_group(sbi, parent_group);
352 ext4_group_t ngroups = ext4_get_groups_count(sb);
353 int flex_size = ext4_flex_bg_size(sbi);
354 ext4_group_t best_flex = parent_fbg_group;
355 int blocks_per_flex = sbi->s_blocks_per_group * flex_size;
356 int flexbg_free_blocks;
357 int flex_freeb_ratio;
358 ext4_group_t n_fbg_groups;
361 n_fbg_groups = (ngroups + flex_size - 1) >>
362 sbi->s_log_groups_per_flex;
364 find_close_to_parent:
365 flexbg_free_blocks = atomic_read(&flex_group[best_flex].free_blocks);
366 flex_freeb_ratio = flexbg_free_blocks * 100 / blocks_per_flex;
367 if (atomic_read(&flex_group[best_flex].free_inodes) &&
368 flex_freeb_ratio > free_block_ratio)
371 if (best_flex && best_flex == parent_fbg_group) {
373 goto find_close_to_parent;
376 for (i = 0; i < n_fbg_groups; i++) {
377 if (i == parent_fbg_group || i == parent_fbg_group - 1)
380 flexbg_free_blocks = atomic_read(&flex_group[i].free_blocks);
381 flex_freeb_ratio = flexbg_free_blocks * 100 / blocks_per_flex;
383 if (flex_freeb_ratio > free_block_ratio &&
384 (atomic_read(&flex_group[i].free_inodes))) {
389 if ((atomic_read(&flex_group[best_flex].free_inodes) == 0) ||
390 ((atomic_read(&flex_group[i].free_blocks) >
391 atomic_read(&flex_group[best_flex].free_blocks)) &&
392 atomic_read(&flex_group[i].free_inodes)))
396 if (!atomic_read(&flex_group[best_flex].free_inodes) ||
397 !atomic_read(&flex_group[best_flex].free_blocks))
401 for (i = best_flex * flex_size; i < ngroups &&
402 i < (best_flex + 1) * flex_size; i++) {
403 desc = ext4_get_group_desc(sb, i, NULL);
404 if (ext4_free_inodes_count(sb, desc)) {
422 * Helper function for Orlov's allocator; returns critical information
423 * for a particular block group or flex_bg. If flex_size is 1, then g
424 * is a block group number; otherwise it is flex_bg number.
426 void get_orlov_stats(struct super_block *sb, ext4_group_t g,
427 int flex_size, struct orlov_stats *stats)
429 struct ext4_group_desc *desc;
430 struct flex_groups *flex_group = EXT4_SB(sb)->s_flex_groups;
433 stats->free_inodes = atomic_read(&flex_group[g].free_inodes);
434 stats->free_blocks = atomic_read(&flex_group[g].free_blocks);
435 stats->used_dirs = atomic_read(&flex_group[g].used_dirs);
439 desc = ext4_get_group_desc(sb, g, NULL);
441 stats->free_inodes = ext4_free_inodes_count(sb, desc);
442 stats->free_blocks = ext4_free_blks_count(sb, desc);
443 stats->used_dirs = ext4_used_dirs_count(sb, desc);
445 stats->free_inodes = 0;
446 stats->free_blocks = 0;
447 stats->used_dirs = 0;
452 * Orlov's allocator for directories.
454 * We always try to spread first-level directories.
456 * If there are blockgroups with both free inodes and free blocks counts
457 * not worse than average we return one with smallest directory count.
458 * Otherwise we simply return a random group.
460 * For the rest rules look so:
462 * It's OK to put directory into a group unless
463 * it has too many directories already (max_dirs) or
464 * it has too few free inodes left (min_inodes) or
465 * it has too few free blocks left (min_blocks) or
466 * Parent's group is preferred, if it doesn't satisfy these
467 * conditions we search cyclically through the rest. If none
468 * of the groups look good we just look for a group with more
469 * free inodes than average (starting at parent's group).
472 static int find_group_orlov(struct super_block *sb, struct inode *parent,
473 ext4_group_t *group, int mode,
474 const struct qstr *qstr)
476 ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
477 struct ext4_sb_info *sbi = EXT4_SB(sb);
478 ext4_group_t real_ngroups = ext4_get_groups_count(sb);
479 int inodes_per_group = EXT4_INODES_PER_GROUP(sb);
480 unsigned int freei, avefreei;
481 ext4_fsblk_t freeb, avefreeb;
483 int max_dirs, min_inodes;
484 ext4_grpblk_t min_blocks;
485 ext4_group_t i, grp, g, ngroups;
486 struct ext4_group_desc *desc;
487 struct orlov_stats stats;
488 int flex_size = ext4_flex_bg_size(sbi);
489 struct dx_hash_info hinfo;
491 ngroups = real_ngroups;
493 ngroups = (real_ngroups + flex_size - 1) >>
494 sbi->s_log_groups_per_flex;
495 parent_group >>= sbi->s_log_groups_per_flex;
498 freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
499 avefreei = freei / ngroups;
500 freeb = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
502 do_div(avefreeb, ngroups);
503 ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
506 ((parent == sb->s_root->d_inode) ||
507 (EXT4_I(parent)->i_flags & EXT4_TOPDIR_FL))) {
508 int best_ndir = inodes_per_group;
512 hinfo.hash_version = DX_HASH_HALF_MD4;
513 hinfo.seed = sbi->s_hash_seed;
514 ext4fs_dirhash(qstr->name, qstr->len, &hinfo);
517 get_random_bytes(&grp, sizeof(grp));
518 parent_group = (unsigned)grp % ngroups;
519 for (i = 0; i < ngroups; i++) {
520 g = (parent_group + i) % ngroups;
521 get_orlov_stats(sb, g, flex_size, &stats);
522 if (!stats.free_inodes)
524 if (stats.used_dirs >= best_ndir)
526 if (stats.free_inodes < avefreei)
528 if (stats.free_blocks < avefreeb)
532 best_ndir = stats.used_dirs;
537 if (flex_size == 1) {
543 * We pack inodes at the beginning of the flexgroup's
544 * inode tables. Block allocation decisions will do
545 * something similar, although regular files will
546 * start at 2nd block group of the flexgroup. See
547 * ext4_ext_find_goal() and ext4_find_near().
550 for (i = 0; i < flex_size; i++) {
551 if (grp+i >= real_ngroups)
553 desc = ext4_get_group_desc(sb, grp+i, NULL);
554 if (desc && ext4_free_inodes_count(sb, desc)) {
562 max_dirs = ndirs / ngroups + inodes_per_group / 16;
563 min_inodes = avefreei - inodes_per_group*flex_size / 4;
566 min_blocks = avefreeb - EXT4_BLOCKS_PER_GROUP(sb)*flex_size / 4;
569 * Start looking in the flex group where we last allocated an
570 * inode for this parent directory
572 if (EXT4_I(parent)->i_last_alloc_group != ~0) {
573 parent_group = EXT4_I(parent)->i_last_alloc_group;
575 parent_group >>= sbi->s_log_groups_per_flex;
578 for (i = 0; i < ngroups; i++) {
579 grp = (parent_group + i) % ngroups;
580 get_orlov_stats(sb, grp, flex_size, &stats);
581 if (stats.used_dirs >= max_dirs)
583 if (stats.free_inodes < min_inodes)
585 if (stats.free_blocks < min_blocks)
591 ngroups = real_ngroups;
592 avefreei = freei / ngroups;
594 parent_group = EXT4_I(parent)->i_block_group;
595 for (i = 0; i < ngroups; i++) {
596 grp = (parent_group + i) % ngroups;
597 desc = ext4_get_group_desc(sb, grp, NULL);
598 if (desc && ext4_free_inodes_count(sb, desc) &&
599 ext4_free_inodes_count(sb, desc) >= avefreei) {
607 * The free-inodes counter is approximate, and for really small
608 * filesystems the above test can fail to find any blockgroups
617 static int find_group_other(struct super_block *sb, struct inode *parent,
618 ext4_group_t *group, int mode)
620 ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
621 ext4_group_t i, last, ngroups = ext4_get_groups_count(sb);
622 struct ext4_group_desc *desc;
623 int flex_size = ext4_flex_bg_size(EXT4_SB(sb));
626 * Try to place the inode is the same flex group as its
627 * parent. If we can't find space, use the Orlov algorithm to
628 * find another flex group, and store that information in the
629 * parent directory's inode information so that use that flex
630 * group for future allocations.
636 parent_group &= ~(flex_size-1);
637 last = parent_group + flex_size;
640 for (i = parent_group; i < last; i++) {
641 desc = ext4_get_group_desc(sb, i, NULL);
642 if (desc && ext4_free_inodes_count(sb, desc)) {
647 if (!retry && EXT4_I(parent)->i_last_alloc_group != ~0) {
649 parent_group = EXT4_I(parent)->i_last_alloc_group;
653 * If this didn't work, use the Orlov search algorithm
654 * to find a new flex group; we pass in the mode to
655 * avoid the topdir algorithms.
657 *group = parent_group + flex_size;
658 if (*group > ngroups)
660 return find_group_orlov(sb, parent, group, mode, 0);
664 * Try to place the inode in its parent directory
666 *group = parent_group;
667 desc = ext4_get_group_desc(sb, *group, NULL);
668 if (desc && ext4_free_inodes_count(sb, desc) &&
669 ext4_free_blks_count(sb, desc))
673 * We're going to place this inode in a different blockgroup from its
674 * parent. We want to cause files in a common directory to all land in
675 * the same blockgroup. But we want files which are in a different
676 * directory which shares a blockgroup with our parent to land in a
677 * different blockgroup.
679 * So add our directory's i_ino into the starting point for the hash.
681 *group = (*group + parent->i_ino) % ngroups;
684 * Use a quadratic hash to find a group with a free inode and some free
687 for (i = 1; i < ngroups; i <<= 1) {
689 if (*group >= ngroups)
691 desc = ext4_get_group_desc(sb, *group, NULL);
692 if (desc && ext4_free_inodes_count(sb, desc) &&
693 ext4_free_blks_count(sb, desc))
698 * That failed: try linear search for a free inode, even if that group
699 * has no free blocks.
701 *group = parent_group;
702 for (i = 0; i < ngroups; i++) {
703 if (++*group >= ngroups)
705 desc = ext4_get_group_desc(sb, *group, NULL);
706 if (desc && ext4_free_inodes_count(sb, desc))
714 * claim the inode from the inode bitmap. If the group
715 * is uninit we need to take the groups's ext4_group_lock
716 * and clear the uninit flag. The inode bitmap update
717 * and group desc uninit flag clear should be done
718 * after holding ext4_group_lock so that ext4_read_inode_bitmap
719 * doesn't race with the ext4_claim_inode
721 static int ext4_claim_inode(struct super_block *sb,
722 struct buffer_head *inode_bitmap_bh,
723 unsigned long ino, ext4_group_t group, int mode)
725 int free = 0, retval = 0, count;
726 struct ext4_sb_info *sbi = EXT4_SB(sb);
727 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
729 ext4_lock_group(sb, group);
730 if (ext4_set_bit(ino, inode_bitmap_bh->b_data)) {
731 /* not a free inode */
736 if ((group == 0 && ino < EXT4_FIRST_INO(sb)) ||
737 ino > EXT4_INODES_PER_GROUP(sb)) {
738 ext4_unlock_group(sb, group);
739 ext4_error(sb, __func__,
740 "reserved inode or inode > inodes count - "
741 "block_group = %u, inode=%lu", group,
742 ino + group * EXT4_INODES_PER_GROUP(sb));
745 /* If we didn't allocate from within the initialized part of the inode
746 * table then we need to initialize up to this inode. */
747 if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
749 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
750 gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
751 /* When marking the block group with
752 * ~EXT4_BG_INODE_UNINIT we don't want to depend
753 * on the value of bg_itable_unused even though
754 * mke2fs could have initialized the same for us.
755 * Instead we calculated the value below
760 free = EXT4_INODES_PER_GROUP(sb) -
761 ext4_itable_unused_count(sb, gdp);
765 * Check the relative inode number against the last used
766 * relative inode number in this group. if it is greater
767 * we need to update the bg_itable_unused count
771 ext4_itable_unused_set(sb, gdp,
772 (EXT4_INODES_PER_GROUP(sb) - ino));
774 count = ext4_free_inodes_count(sb, gdp) - 1;
775 ext4_free_inodes_set(sb, gdp, count);
777 count = ext4_used_dirs_count(sb, gdp) + 1;
778 ext4_used_dirs_set(sb, gdp, count);
779 if (sbi->s_log_groups_per_flex) {
780 ext4_group_t f = ext4_flex_group(sbi, group);
782 atomic_inc(&sbi->s_flex_groups[f].free_inodes);
785 gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp);
787 ext4_unlock_group(sb, group);
792 * There are two policies for allocating an inode. If the new inode is
793 * a directory, then a forward search is made for a block group with both
794 * free space and a low directory-to-inode ratio; if that fails, then of
795 * the groups with above-average free space, that group with the fewest
796 * directories already is chosen.
798 * For other inodes, search forward from the parent directory's block
799 * group to find a free inode.
801 struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, int mode,
802 const struct qstr *qstr, __u32 goal)
804 struct super_block *sb;
805 struct buffer_head *inode_bitmap_bh = NULL;
806 struct buffer_head *group_desc_bh;
807 ext4_group_t ngroups, group = 0;
808 unsigned long ino = 0;
810 struct ext4_group_desc *gdp = NULL;
811 struct ext4_inode_info *ei;
812 struct ext4_sb_info *sbi;
818 ext4_group_t flex_group;
820 /* Cannot create files in a deleted directory */
821 if (!dir || !dir->i_nlink)
822 return ERR_PTR(-EPERM);
825 ngroups = ext4_get_groups_count(sb);
826 trace_ext4_request_inode(dir, mode);
827 inode = new_inode(sb);
829 return ERR_PTR(-ENOMEM);
834 goal = sbi->s_inode_goal;
836 if (goal && goal <= le32_to_cpu(sbi->s_es->s_inodes_count)) {
837 group = (goal - 1) / EXT4_INODES_PER_GROUP(sb);
838 ino = (goal - 1) % EXT4_INODES_PER_GROUP(sb);
843 if (sbi->s_log_groups_per_flex && test_opt(sb, OLDALLOC)) {
844 ret2 = find_group_flex(sb, dir, &group);
846 ret2 = find_group_other(sb, dir, &group, mode);
847 if (ret2 == 0 && once) {
849 printk(KERN_NOTICE "ext4: find_group_flex "
850 "failed, fallback succeeded dir %lu\n",
858 if (test_opt(sb, OLDALLOC))
859 ret2 = find_group_dir(sb, dir, &group);
861 ret2 = find_group_orlov(sb, dir, &group, mode, qstr);
863 ret2 = find_group_other(sb, dir, &group, mode);
866 EXT4_I(dir)->i_last_alloc_group = group;
871 for (i = 0; i < ngroups; i++, ino = 0) {
874 gdp = ext4_get_group_desc(sb, group, &group_desc_bh);
878 brelse(inode_bitmap_bh);
879 inode_bitmap_bh = ext4_read_inode_bitmap(sb, group);
880 if (!inode_bitmap_bh)
883 repeat_in_this_group:
884 ino = ext4_find_next_zero_bit((unsigned long *)
885 inode_bitmap_bh->b_data,
886 EXT4_INODES_PER_GROUP(sb), ino);
888 if (ino < EXT4_INODES_PER_GROUP(sb)) {
890 BUFFER_TRACE(inode_bitmap_bh, "get_write_access");
891 err = ext4_journal_get_write_access(handle,
896 BUFFER_TRACE(group_desc_bh, "get_write_access");
897 err = ext4_journal_get_write_access(handle,
901 if (!ext4_claim_inode(sb, inode_bitmap_bh,
904 BUFFER_TRACE(inode_bitmap_bh,
905 "call ext4_handle_dirty_metadata");
906 err = ext4_handle_dirty_metadata(handle,
911 /* zero bit is inode number 1*/
916 ext4_handle_release_buffer(handle, inode_bitmap_bh);
917 ext4_handle_release_buffer(handle, group_desc_bh);
919 if (++ino < EXT4_INODES_PER_GROUP(sb))
920 goto repeat_in_this_group;
924 * This case is possible in concurrent environment. It is very
925 * rare. We cannot repeat the find_group_xxx() call because
926 * that will simply return the same blockgroup, because the
927 * group descriptor metadata has not yet been updated.
928 * So we just go onto the next blockgroup.
930 if (++group == ngroups)
937 /* We may have to initialize the block bitmap if it isn't already */
938 if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
939 gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
940 struct buffer_head *block_bitmap_bh;
942 block_bitmap_bh = ext4_read_block_bitmap(sb, group);
943 BUFFER_TRACE(block_bitmap_bh, "get block bitmap access");
944 err = ext4_journal_get_write_access(handle, block_bitmap_bh);
946 brelse(block_bitmap_bh);
951 ext4_lock_group(sb, group);
952 /* recheck and clear flag under lock if we still need to */
953 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
954 free = ext4_free_blocks_after_init(sb, group, gdp);
955 gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
956 ext4_free_blks_set(sb, gdp, free);
957 gdp->bg_checksum = ext4_group_desc_csum(sbi, group,
960 ext4_unlock_group(sb, group);
962 /* Don't need to dirty bitmap block if we didn't change it */
964 BUFFER_TRACE(block_bitmap_bh, "dirty block bitmap");
965 err = ext4_handle_dirty_metadata(handle,
966 NULL, block_bitmap_bh);
969 brelse(block_bitmap_bh);
973 BUFFER_TRACE(group_desc_bh, "call ext4_handle_dirty_metadata");
974 err = ext4_handle_dirty_metadata(handle, NULL, group_desc_bh);
978 percpu_counter_dec(&sbi->s_freeinodes_counter);
980 percpu_counter_inc(&sbi->s_dirs_counter);
983 if (sbi->s_log_groups_per_flex) {
984 flex_group = ext4_flex_group(sbi, group);
985 atomic_dec(&sbi->s_flex_groups[flex_group].free_inodes);
988 inode->i_uid = current_fsuid();
989 if (test_opt(sb, GRPID))
990 inode->i_gid = dir->i_gid;
991 else if (dir->i_mode & S_ISGID) {
992 inode->i_gid = dir->i_gid;
996 inode->i_gid = current_fsgid();
997 inode->i_mode = mode;
999 inode->i_ino = ino + group * EXT4_INODES_PER_GROUP(sb);
1000 /* This is the optimal IO size (for stat), not the fs block size */
1001 inode->i_blocks = 0;
1002 inode->i_mtime = inode->i_atime = inode->i_ctime = ei->i_crtime =
1003 ext4_current_time(inode);
1005 memset(ei->i_data, 0, sizeof(ei->i_data));
1006 ei->i_dir_start_lookup = 0;
1010 * Don't inherit extent flag from directory, amongst others. We set
1011 * extent flag on newly created directory and file only if -o extent
1012 * mount option is specified
1015 ext4_mask_flags(mode, EXT4_I(dir)->i_flags & EXT4_FL_INHERITED);
1018 ei->i_block_group = group;
1019 ei->i_last_alloc_group = ~0;
1021 ext4_set_inode_flags(inode);
1022 if (IS_DIRSYNC(inode))
1023 ext4_handle_sync(handle);
1024 if (insert_inode_locked(inode) < 0) {
1028 spin_lock(&sbi->s_next_gen_lock);
1029 inode->i_generation = sbi->s_next_generation++;
1030 spin_unlock(&sbi->s_next_gen_lock);
1032 ei->i_state = EXT4_STATE_NEW;
1034 ei->i_extra_isize = EXT4_SB(sb)->s_want_extra_isize;
1037 if (vfs_dq_alloc_inode(inode)) {
1042 err = ext4_init_acl(handle, inode, dir);
1044 goto fail_free_drop;
1046 err = ext4_init_security(handle, inode, dir);
1048 goto fail_free_drop;
1050 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
1051 /* set extent flag only for directory, file and normal symlink*/
1052 if (S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode)) {
1053 EXT4_I(inode)->i_flags |= EXT4_EXTENTS_FL;
1054 ext4_ext_tree_init(handle, inode);
1058 err = ext4_mark_inode_dirty(handle, inode);
1060 ext4_std_error(sb, err);
1061 goto fail_free_drop;
1064 ext4_debug("allocating inode %lu\n", inode->i_ino);
1065 trace_ext4_allocate_inode(inode, dir, mode);
1068 ext4_std_error(sb, err);
1073 brelse(inode_bitmap_bh);
1077 vfs_dq_free_inode(inode);
1081 inode->i_flags |= S_NOQUOTA;
1083 unlock_new_inode(inode);
1085 brelse(inode_bitmap_bh);
1086 return ERR_PTR(err);
1089 /* Verify that we are loading a valid orphan from disk */
1090 struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino)
1092 unsigned long max_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count);
1093 ext4_group_t block_group;
1095 struct buffer_head *bitmap_bh;
1096 struct inode *inode = NULL;
1099 /* Error cases - e2fsck has already cleaned up for us */
1100 if (ino > max_ino) {
1101 ext4_warning(sb, __func__,
1102 "bad orphan ino %lu! e2fsck was run?", ino);
1106 block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
1107 bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
1108 bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
1110 ext4_warning(sb, __func__,
1111 "inode bitmap error for orphan %lu", ino);
1115 /* Having the inode bit set should be a 100% indicator that this
1116 * is a valid orphan (no e2fsck run on fs). Orphans also include
1117 * inodes that were being truncated, so we can't check i_nlink==0.
1119 if (!ext4_test_bit(bit, bitmap_bh->b_data))
1122 inode = ext4_iget(sb, ino);
1127 * If the orphans has i_nlinks > 0 then it should be able to be
1128 * truncated, otherwise it won't be removed from the orphan list
1129 * during processing and an infinite loop will result.
1131 if (inode->i_nlink && !ext4_can_truncate(inode))
1134 if (NEXT_ORPHAN(inode) > max_ino)
1140 err = PTR_ERR(inode);
1143 ext4_warning(sb, __func__,
1144 "bad orphan inode %lu! e2fsck was run?", ino);
1145 printk(KERN_NOTICE "ext4_test_bit(bit=%d, block=%llu) = %d\n",
1146 bit, (unsigned long long)bitmap_bh->b_blocknr,
1147 ext4_test_bit(bit, bitmap_bh->b_data));
1148 printk(KERN_NOTICE "inode=%p\n", inode);
1150 printk(KERN_NOTICE "is_bad_inode(inode)=%d\n",
1151 is_bad_inode(inode));
1152 printk(KERN_NOTICE "NEXT_ORPHAN(inode)=%u\n",
1153 NEXT_ORPHAN(inode));
1154 printk(KERN_NOTICE "max_ino=%lu\n", max_ino);
1155 printk(KERN_NOTICE "i_nlink=%u\n", inode->i_nlink);
1156 /* Avoid freeing blocks if we got a bad deleted inode */
1157 if (inode->i_nlink == 0)
1158 inode->i_blocks = 0;
1163 return ERR_PTR(err);
1166 unsigned long ext4_count_free_inodes(struct super_block *sb)
1168 unsigned long desc_count;
1169 struct ext4_group_desc *gdp;
1170 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
1172 struct ext4_super_block *es;
1173 unsigned long bitmap_count, x;
1174 struct buffer_head *bitmap_bh = NULL;
1176 es = EXT4_SB(sb)->s_es;
1180 for (i = 0; i < ngroups; i++) {
1181 gdp = ext4_get_group_desc(sb, i, NULL);
1184 desc_count += ext4_free_inodes_count(sb, gdp);
1186 bitmap_bh = ext4_read_inode_bitmap(sb, i);
1190 x = ext4_count_free(bitmap_bh, EXT4_INODES_PER_GROUP(sb) / 8);
1191 printk(KERN_DEBUG "group %lu: stored = %d, counted = %lu\n",
1192 (unsigned long) i, ext4_free_inodes_count(sb, gdp), x);
1196 printk(KERN_DEBUG "ext4_count_free_inodes: "
1197 "stored = %u, computed = %lu, %lu\n",
1198 le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
1202 for (i = 0; i < ngroups; i++) {
1203 gdp = ext4_get_group_desc(sb, i, NULL);
1206 desc_count += ext4_free_inodes_count(sb, gdp);
1213 /* Called at mount-time, super-block is locked */
1214 unsigned long ext4_count_dirs(struct super_block * sb)
1216 unsigned long count = 0;
1217 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
1219 for (i = 0; i < ngroups; i++) {
1220 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1223 count += ext4_used_dirs_count(sb, gdp);