fs/ntfs3/inode.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *
   4  * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
   5  *
   6  */
   7
   8 #include <linux/buffer_head.h>
   9 #include <linux/fs.h>
  10 #include <linux/mpage.h>
  11 #include <linux/namei.h>
  12 #include <linux/nls.h>
  13 #include <linux/uio.h>
  14 #include <linux/writeback.h>
  15
  16 #include "debug.h"
  17 #include "ntfs.h"
  18 #include "ntfs_fs.h"
  19
  20 /*
  21  * ntfs_read_mft - Read record and parse MFT.
  22  */
  23 static struct inode *ntfs_read_mft(struct inode *inode,
  24                                    const struct cpu_str *name,
  25                                    const struct MFT_REF *ref)
  26 {
  27         int err = 0;
  28         struct ntfs_inode *ni = ntfs_i(inode);
  29         struct super_block *sb = inode->i_sb;
  30         struct ntfs_sb_info *sbi = sb->s_fs_info;
  31         mode_t mode = 0;
  32         struct ATTR_STD_INFO5 *std5 = NULL;
  33         struct ATTR_LIST_ENTRY *le;
  34         struct ATTRIB *attr;
  35         bool is_match = false;
  36         bool is_root = false;
  37         bool is_dir;
  38         unsigned long ino = inode->i_ino;
  39         u32 rp_fa = 0, asize, t32;
  40         u16 roff, rsize, names = 0, links = 0;
  41         const struct ATTR_FILE_NAME *fname = NULL;
  42         const struct INDEX_ROOT *root;
  43         struct REPARSE_DATA_BUFFER rp; // 0x18 bytes
  44         u64 t64;
  45         struct MFT_REC *rec;
  46         struct runs_tree *run;
  47         struct timespec64 ts;
  48
  49         inode->i_op = NULL;
  50         /* Setup 'uid' and 'gid' */
  51         inode->i_uid = sbi->options->fs_uid;
  52         inode->i_gid = sbi->options->fs_gid;
  53
  54         err = mi_init(&ni->mi, sbi, ino);
  55         if (err)
  56                 goto out;
  57
  58         if (!sbi->mft.ni && ino == MFT_REC_MFT && !sb->s_root) {
  59                 t64 = sbi->mft.lbo >> sbi->cluster_bits;
  60                 t32 = bytes_to_cluster(sbi, MFT_REC_VOL * sbi->record_size);
  61                 sbi->mft.ni = ni;
  62                 init_rwsem(&ni->file.run_lock);
  63
  64                 if (!run_add_entry(&ni->file.run, 0, t64, t32, true)) {
  65                         err = -ENOMEM;
  66                         goto out;
  67                 }
  68         }
  69
  70         err = mi_read(&ni->mi, ino == MFT_REC_MFT);
  71
  72         if (err)
  73                 goto out;
  74
  75         rec = ni->mi.mrec;
  76
  77         if (sbi->flags & NTFS_FLAGS_LOG_REPLAYING) {
  78                 ;
  79         } else if (ref->seq != rec->seq) {
  80                 err = -EINVAL;
  81                 ntfs_err(sb, "MFT: r=%lx, expect seq=%x instead of %x!", ino,
  82                          le16_to_cpu(ref->seq), le16_to_cpu(rec->seq));
  83                 goto out;
  84         } else if (!is_rec_inuse(rec)) {
  85                 err = -ESTALE;
  86                 ntfs_err(sb, "Inode r=%x is not in use!", (u32)ino);
  87                 goto out;
  88         }
  89
  90         if (le32_to_cpu(rec->total) != sbi->record_size) {
  91                 /* Bad inode? */
  92                 err = -EINVAL;
  93                 goto out;
  94         }
  95
  96         if (!is_rec_base(rec)) {
  97                 err = -EINVAL;
  98                 goto out;
  99         }
 100
 101         /* Record should contain $I30 root. */
 102         is_dir = rec->flags & RECORD_FLAG_DIR;
 103
 104         /* MFT_REC_MFT is not a dir */
 105         if (is_dir && ino == MFT_REC_MFT) {
 106                 err = -EINVAL;
 107                 goto out;
 108         }
 109
 110         inode->i_generation = le16_to_cpu(rec->seq);
 111
 112         /* Enumerate all struct Attributes MFT. */
 113         le = NULL;
 114         attr = NULL;
 115
 116         /*
 117          * To reduce tab pressure use goto instead of
 118          * while( (attr = ni_enum_attr_ex(ni, attr, &le, NULL) ))
 119          */
 120 next_attr:
 121         run = NULL;
 122         err = -EINVAL;
 123         attr = ni_enum_attr_ex(ni, attr, &le, NULL);
 124         if (!attr)
 125                 goto end_enum;
 126
 127         if (le && le->vcn) {
 128                 /* This is non primary attribute segment. Ignore if not MFT. */
 129                 if (ino != MFT_REC_MFT || attr->type != ATTR_DATA)
 130                         goto next_attr;
 131
 132                 run = &ni->file.run;
 133                 asize = le32_to_cpu(attr->size);
 134                 goto attr_unpack_run;
 135         }
 136
 137         roff = attr->non_res ? 0 : le16_to_cpu(attr->res.data_off);
 138         rsize = attr->non_res ? 0 : le32_to_cpu(attr->res.data_size);
 139         asize = le32_to_cpu(attr->size);
 140
 141         /*
 142          * Really this check was done in 'ni_enum_attr_ex' -> ... 'mi_enum_attr'.
 143          * There not critical to check this case again
 144          */
 145         if (attr->name_len &&
 146             sizeof(short) * attr->name_len + le16_to_cpu(attr->name_off) >
 147                     asize)
 148                 goto out;
 149
 150         if (attr->non_res) {
 151                 t64 = le64_to_cpu(attr->nres.alloc_size);
 152                 if (le64_to_cpu(attr->nres.data_size) > t64 ||
 153                     le64_to_cpu(attr->nres.valid_size) > t64)
 154                         goto out;
 155         }
 156
 157         switch (attr->type) {
 158         case ATTR_STD:
 159                 if (attr->non_res ||
 160                     asize < sizeof(struct ATTR_STD_INFO) + roff ||
 161                     rsize < sizeof(struct ATTR_STD_INFO))
 162                         goto out;
 163
 164                 if (std5)
 165                         goto next_attr;
 166
 167                 std5 = Add2Ptr(attr, roff);
 168
 169 #ifdef STATX_BTIME
 170                 nt2kernel(std5->cr_time, &ni->i_crtime);
 171 #endif
 172                 nt2kernel(std5->a_time, &ts);
 173                 inode_set_atime_to_ts(inode, ts);
 174                 nt2kernel(std5->c_time, &ts);
 175                 inode_set_ctime_to_ts(inode, ts);
 176                 nt2kernel(std5->m_time, &ts);
 177                 inode_set_mtime_to_ts(inode, ts);
 178
 179                 ni->std_fa = std5->fa;
 180
 181                 if (asize >= sizeof(struct ATTR_STD_INFO5) + roff &&
 182                     rsize >= sizeof(struct ATTR_STD_INFO5))
 183                         ni->std_security_id = std5->security_id;
 184                 goto next_attr;
 185
 186         case ATTR_LIST:
 187                 if (attr->name_len || le || ino == MFT_REC_LOG)
 188                         goto out;
 189
 190                 err = ntfs_load_attr_list(ni, attr);
 191                 if (err)
 192                         goto out;
 193
 194                 le = NULL;
 195                 attr = NULL;
 196                 goto next_attr;
 197
 198         case ATTR_NAME:
 199                 if (attr->non_res || asize < SIZEOF_ATTRIBUTE_FILENAME + roff ||
 200                     rsize < SIZEOF_ATTRIBUTE_FILENAME)
 201                         goto out;
 202
 203                 names += 1;
 204                 fname = Add2Ptr(attr, roff);
 205                 if (fname->type == FILE_NAME_DOS)
 206                         goto next_attr;
 207
 208                 links += 1;
 209                 if (name && name->len == fname->name_len &&
 210                     !ntfs_cmp_names_cpu(name, (struct le_str *)&fname->name_len,
 211                                         NULL, false))
 212                         is_match = true;
 213
 214                 goto next_attr;
 215
 216         case ATTR_DATA:
 217                 if (is_dir) {
 218                         /* Ignore data attribute in dir record. */
 219                         goto next_attr;
 220                 }
 221
 222                 if (ino == MFT_REC_BADCLUST && !attr->non_res)
 223                         goto next_attr;
 224
 225                 if (attr->name_len &&
 226                     ((ino != MFT_REC_BADCLUST || !attr->non_res ||
 227                       attr->name_len != ARRAY_SIZE(BAD_NAME) ||
 228                       memcmp(attr_name(attr), BAD_NAME, sizeof(BAD_NAME))) &&
 229                      (ino != MFT_REC_SECURE || !attr->non_res ||
 230                       attr->name_len != ARRAY_SIZE(SDS_NAME) ||
 231                       memcmp(attr_name(attr), SDS_NAME, sizeof(SDS_NAME))))) {
 232                         /* File contains stream attribute. Ignore it. */
 233                         goto next_attr;
 234                 }
 235
 236                 if (is_attr_sparsed(attr))
 237                         ni->std_fa |= FILE_ATTRIBUTE_SPARSE_FILE;
 238                 else
 239                         ni->std_fa &= ~FILE_ATTRIBUTE_SPARSE_FILE;
 240
 241                 if (is_attr_compressed(attr))
 242                         ni->std_fa |= FILE_ATTRIBUTE_COMPRESSED;
 243                 else
 244                         ni->std_fa &= ~FILE_ATTRIBUTE_COMPRESSED;
 245
 246                 if (is_attr_encrypted(attr))
 247                         ni->std_fa |= FILE_ATTRIBUTE_ENCRYPTED;
 248                 else
 249                         ni->std_fa &= ~FILE_ATTRIBUTE_ENCRYPTED;
 250
 251                 if (!attr->non_res) {
 252                         ni->i_valid = inode->i_size = rsize;
 253                         inode_set_bytes(inode, rsize);
 254                 }
 255
 256                 mode = S_IFREG | (0777 & sbi->options->fs_fmask_inv);
 257
 258                 if (!attr->non_res) {
 259                         ni->ni_flags |= NI_FLAG_RESIDENT;
 260                         goto next_attr;
 261                 }
 262
 263                 inode_set_bytes(inode, attr_ondisk_size(attr));
 264
 265                 ni->i_valid = le64_to_cpu(attr->nres.valid_size);
 266                 inode->i_size = le64_to_cpu(attr->nres.data_size);
 267                 if (!attr->nres.alloc_size)
 268                         goto next_attr;
 269
 270                 run = ino == MFT_REC_BITMAP ? &sbi->used.bitmap.run :
 271                                               &ni->file.run;
 272                 break;
 273
 274         case ATTR_ROOT:
 275                 if (attr->non_res)
 276                         goto out;
 277
 278                 root = Add2Ptr(attr, roff);
 279
 280                 if (attr->name_len != ARRAY_SIZE(I30_NAME) ||
 281                     memcmp(attr_name(attr), I30_NAME, sizeof(I30_NAME)))
 282                         goto next_attr;
 283
 284                 if (root->type != ATTR_NAME ||
 285                     root->rule != NTFS_COLLATION_TYPE_FILENAME)
 286                         goto out;
 287
 288                 if (!is_dir)
 289                         goto next_attr;
 290
 291                 is_root = true;
 292                 ni->ni_flags |= NI_FLAG_DIR;
 293
 294                 err = indx_init(&ni->dir, sbi, attr, INDEX_MUTEX_I30);
 295                 if (err)
 296                         goto out;
 297
 298                 mode = sb->s_root ?
 299                                (S_IFDIR | (0777 & sbi->options->fs_dmask_inv)) :
 300                                (S_IFDIR | 0777);
 301                 goto next_attr;
 302
 303         case ATTR_ALLOC:
 304                 if (!is_root || attr->name_len != ARRAY_SIZE(I30_NAME) ||
 305                     memcmp(attr_name(attr), I30_NAME, sizeof(I30_NAME)))
 306                         goto next_attr;
 307
 308                 inode->i_size = le64_to_cpu(attr->nres.data_size);
 309                 ni->i_valid = le64_to_cpu(attr->nres.valid_size);
 310                 inode_set_bytes(inode, le64_to_cpu(attr->nres.alloc_size));
 311
 312                 run = &ni->dir.alloc_run;
 313                 break;
 314
 315         case ATTR_BITMAP:
 316                 if (ino == MFT_REC_MFT) {
 317                         if (!attr->non_res)
 318                                 goto out;
 319 #ifndef CONFIG_NTFS3_64BIT_CLUSTER
 320                         /* 0x20000000 = 2^32 / 8 */
 321                         if (le64_to_cpu(attr->nres.alloc_size) >= 0x20000000)
 322                                 goto out;
 323 #endif
 324                         run = &sbi->mft.bitmap.run;
 325                         break;
 326                 } else if (is_dir && attr->name_len == ARRAY_SIZE(I30_NAME) &&
 327                            !memcmp(attr_name(attr), I30_NAME,
 328                                    sizeof(I30_NAME)) &&
 329                            attr->non_res) {
 330                         run = &ni->dir.bitmap_run;
 331                         break;
 332                 }
 333                 goto next_attr;
 334
 335         case ATTR_REPARSE:
 336                 if (attr->name_len)
 337                         goto next_attr;
 338
 339                 rp_fa = ni_parse_reparse(ni, attr, &rp);
 340                 switch (rp_fa) {
 341                 case REPARSE_LINK:
 342                         /*
 343                          * Normal symlink.
 344                          * Assume one unicode symbol == one utf8.
 345                          */
 346                         inode->i_size = le16_to_cpu(rp.SymbolicLinkReparseBuffer
 347                                                             .PrintNameLength) /
 348                                         sizeof(u16);
 349                         ni->i_valid = inode->i_size;
 350                         /* Clear directory bit. */
 351                         if (ni->ni_flags & NI_FLAG_DIR) {
 352                                 indx_clear(&ni->dir);
 353                                 memset(&ni->dir, 0, sizeof(ni->dir));
 354                                 ni->ni_flags &= ~NI_FLAG_DIR;
 355                         } else {
 356                                 run_close(&ni->file.run);
 357                         }
 358                         mode = S_IFLNK | 0777;
 359                         is_dir = false;
 360                         if (attr->non_res) {
 361                                 run = &ni->file.run;
 362                                 goto attr_unpack_run; // Double break.
 363                         }
 364                         break;
 365
 366                 case REPARSE_COMPRESSED:
 367                         break;
 368
 369                 case REPARSE_DEDUPLICATED:
 370                         break;
 371                 }
 372                 goto next_attr;
 373
 374         case ATTR_EA_INFO:
 375                 if (!attr->name_len &&
 376                     resident_data_ex(attr, sizeof(struct EA_INFO))) {
 377                         ni->ni_flags |= NI_FLAG_EA;
 378                         /*
 379                          * ntfs_get_wsl_perm updates inode->i_uid, inode->i_gid, inode->i_mode
 380                          */
 381                         inode->i_mode = mode;
 382                         ntfs_get_wsl_perm(inode);
 383                         mode = inode->i_mode;
 384                 }
 385                 goto next_attr;
 386
 387         default:
 388                 goto next_attr;
 389         }
 390
 391 attr_unpack_run:
 392         roff = le16_to_cpu(attr->nres.run_off);
 393
 394         if (roff > asize) {
 395                 err = -EINVAL;
 396                 goto out;
 397         }
 398
 399         t64 = le64_to_cpu(attr->nres.svcn);
 400
 401         err = run_unpack_ex(run, sbi, ino, t64, le64_to_cpu(attr->nres.evcn),
 402                             t64, Add2Ptr(attr, roff), asize - roff);
 403         if (err < 0)
 404                 goto out;
 405         err = 0;
 406         goto next_attr;
 407
 408 end_enum:
 409
 410         if (!std5)
 411                 goto out;
 412
 413         if (!is_match && name) {
 414                 err = -ENOENT;
 415                 goto out;
 416         }
 417
 418         if (std5->fa & FILE_ATTRIBUTE_READONLY)
 419                 mode &= ~0222;
 420
 421         if (!names) {
 422                 err = -EINVAL;
 423                 goto out;
 424         }
 425
 426         if (names != le16_to_cpu(rec->hard_links)) {
 427                 /* Correct minor error on the fly. Do not mark inode as dirty. */
 428                 ntfs_inode_warn(inode, "Correct links count -> %u.", names);
 429                 rec->hard_links = cpu_to_le16(names);
 430                 ni->mi.dirty = true;
 431         }
 432
 433         set_nlink(inode, links);
 434
 435         if (S_ISDIR(mode)) {
 436                 ni->std_fa |= FILE_ATTRIBUTE_DIRECTORY;
 437
 438                 /*
 439                  * Dot and dot-dot should be included in count but was not
 440                  * included in enumeration.
 441                  * Usually a hard links to directories are disabled.
 442                  */
 443                 inode->i_op = &ntfs_dir_inode_operations;
 444                 inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
 445                                        &ntfs_legacy_dir_operations :
 446                                        &ntfs_dir_operations;
 447                 ni->i_valid = 0;
 448         } else if (S_ISLNK(mode)) {
 449                 ni->std_fa &= ~FILE_ATTRIBUTE_DIRECTORY;
 450                 inode->i_op = &ntfs_link_inode_operations;
 451                 inode->i_fop = NULL;
 452                 inode_nohighmem(inode);
 453         } else if (S_ISREG(mode)) {
 454                 ni->std_fa &= ~FILE_ATTRIBUTE_DIRECTORY;
 455                 inode->i_op = &ntfs_file_inode_operations;
 456                 inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
 457                                        &ntfs_legacy_file_operations :
 458                                        &ntfs_file_operations;
 459                 inode->i_mapping->a_ops = is_compressed(ni) ? &ntfs_aops_cmpr :
 460                                                               &ntfs_aops;
 461                 if (ino != MFT_REC_MFT)
 462                         init_rwsem(&ni->file.run_lock);
 463         } else if (S_ISCHR(mode) || S_ISBLK(mode) || S_ISFIFO(mode) ||
 464                    S_ISSOCK(mode)) {
 465                 inode->i_op = &ntfs_special_inode_operations;
 466                 init_special_inode(inode, mode, inode->i_rdev);
 467         } else if (fname && fname->home.low == cpu_to_le32(MFT_REC_EXTEND) &&
 468                    fname->home.seq == cpu_to_le16(MFT_REC_EXTEND)) {
 469                 /* Records in $Extend are not a files or general directories. */
 470                 inode->i_op = &ntfs_file_inode_operations;
 471         } else {
 472                 err = -EINVAL;
 473                 goto out;
 474         }
 475
 476         if ((sbi->options->sys_immutable &&
 477              (std5->fa & FILE_ATTRIBUTE_SYSTEM)) &&
 478             !S_ISFIFO(mode) && !S_ISSOCK(mode) && !S_ISLNK(mode)) {
 479                 inode->i_flags |= S_IMMUTABLE;
 480         } else {
 481                 inode->i_flags &= ~S_IMMUTABLE;
 482         }
 483
 484         inode->i_mode = mode;
 485         if (!(ni->ni_flags & NI_FLAG_EA)) {
 486                 /* If no xattr then no security (stored in xattr). */
 487                 inode->i_flags |= S_NOSEC;
 488         }
 489
 490         if (ino == MFT_REC_MFT && !sb->s_root)
 491                 sbi->mft.ni = NULL;
 492
 493         unlock_new_inode(inode);
 494
 495         return inode;
 496
 497 out:
 498         if (ino == MFT_REC_MFT && !sb->s_root)
 499                 sbi->mft.ni = NULL;
 500
 501         iget_failed(inode);
 502         return ERR_PTR(err);
 503 }
 504
 505 /*
 506  * ntfs_test_inode
 507  *
 508  * Return: 1 if match.
 509  */
 510 static int ntfs_test_inode(struct inode *inode, void *data)
 511 {
 512         struct MFT_REF *ref = data;
 513
 514         return ino_get(ref) == inode->i_ino;
 515 }
 516
 517 static int ntfs_set_inode(struct inode *inode, void *data)
 518 {
 519         const struct MFT_REF *ref = data;
 520
 521         inode->i_ino = ino_get(ref);
 522         return 0;
 523 }
 524
 525 struct inode *ntfs_iget5(struct super_block *sb, const struct MFT_REF *ref,
 526                          const struct cpu_str *name)
 527 {
 528         struct inode *inode;
 529
 530         inode = iget5_locked(sb, ino_get(ref), ntfs_test_inode, ntfs_set_inode,
 531                              (void *)ref);
 532         if (unlikely(!inode))
 533                 return ERR_PTR(-ENOMEM);
 534
 535         /* If this is a freshly allocated inode, need to read it now. */
 536         if (inode->i_state & I_NEW)
 537                 inode = ntfs_read_mft(inode, name, ref);
 538         else if (ref->seq != ntfs_i(inode)->mi.mrec->seq) {
 539                 /* Inode overlaps? */
 540                 _ntfs_bad_inode(inode);
 541         }
 542
 543         if (IS_ERR(inode) && name)
 544                 ntfs_set_state(sb->s_fs_info, NTFS_DIRTY_ERROR);
 545
 546         return inode;
 547 }
 548
 549 enum get_block_ctx {
 550         GET_BLOCK_GENERAL = 0,
 551         GET_BLOCK_WRITE_BEGIN = 1,
 552         GET_BLOCK_DIRECT_IO_R = 2,
 553         GET_BLOCK_DIRECT_IO_W = 3,
 554         GET_BLOCK_BMAP = 4,
 555 };
 556
 557 static noinline int ntfs_get_block_vbo(struct inode *inode, u64 vbo,
 558                                        struct buffer_head *bh, int create,
 559                                        enum get_block_ctx ctx)
 560 {
 561         struct super_block *sb = inode->i_sb;
 562         struct ntfs_sb_info *sbi = sb->s_fs_info;
 563         struct ntfs_inode *ni = ntfs_i(inode);
 564         struct folio *folio = bh->b_folio;
 565         u8 cluster_bits = sbi->cluster_bits;
 566         u32 block_size = sb->s_blocksize;
 567         u64 bytes, lbo, valid;
 568         u32 off;
 569         int err;
 570         CLST vcn, lcn, len;
 571         bool new;
 572
 573         /* Clear previous state. */
 574         clear_buffer_new(bh);
 575         clear_buffer_uptodate(bh);
 576
 577         if (is_resident(ni)) {
 578                 bh->b_blocknr = RESIDENT_LCN;
 579                 bh->b_size = block_size;
 580                 if (!folio) {
 581                         /* direct io (read) or bmap call */
 582                         err = 0;
 583                 } else {
 584                         ni_lock(ni);
 585                         err = attr_data_read_resident(ni, folio);
 586                         ni_unlock(ni);
 587
 588                         if (!err)
 589                                 set_buffer_uptodate(bh);
 590                 }
 591                 return err;
 592         }
 593
 594         vcn = vbo >> cluster_bits;
 595         off = vbo & sbi->cluster_mask;
 596         new = false;
 597
 598         err = attr_data_get_block(ni, vcn, 1, &lcn, &len, create ? &new : NULL,
 599                                   create && sbi->cluster_size > PAGE_SIZE);
 600         if (err)
 601                 goto out;
 602
 603         if (!len)
 604                 return 0;
 605
 606         bytes = ((u64)len << cluster_bits) - off;
 607
 608         if (lcn == SPARSE_LCN) {
 609                 if (!create) {
 610                         if (bh->b_size > bytes)
 611                                 bh->b_size = bytes;
 612                         return 0;
 613                 }
 614                 WARN_ON(1);
 615         }
 616
 617         if (new)
 618                 set_buffer_new(bh);
 619
 620         lbo = ((u64)lcn << cluster_bits) + off;
 621
 622         set_buffer_mapped(bh);
 623         bh->b_bdev = sb->s_bdev;
 624         bh->b_blocknr = lbo >> sb->s_blocksize_bits;
 625
 626         valid = ni->i_valid;
 627
 628         if (ctx == GET_BLOCK_DIRECT_IO_W) {
 629                 /* ntfs_direct_IO will update ni->i_valid. */
 630                 if (vbo >= valid)
 631                         set_buffer_new(bh);
 632         } else if (create) {
 633                 /* Normal write. */
 634                 if (bytes > bh->b_size)
 635                         bytes = bh->b_size;
 636
 637                 if (vbo >= valid)
 638                         set_buffer_new(bh);
 639
 640                 if (vbo + bytes > valid) {
 641                         ni->i_valid = vbo + bytes;
 642                         mark_inode_dirty(inode);
 643                 }
 644         } else if (vbo >= valid) {
 645                 /* Read out of valid data. */
 646                 clear_buffer_mapped(bh);
 647         } else if (vbo + bytes <= valid) {
 648                 /* Normal read. */
 649         } else if (vbo + block_size <= valid) {
 650                 /* Normal short read. */
 651                 bytes = block_size;
 652         } else {
 653                 /*
 654                  * Read across valid size: vbo < valid && valid < vbo + block_size
 655                  */
 656                 bytes = block_size;
 657
 658                 if (folio) {
 659                         u32 voff = valid - vbo;
 660
 661                         bh->b_size = block_size;
 662                         off = vbo & (PAGE_SIZE - 1);
 663                         folio_set_bh(bh, folio, off);
 664
 665                         if (bh_read(bh, 0) < 0) {
 666                                 err = -EIO;
 667                                 goto out;
 668                         }
 669                         folio_zero_segment(folio, off + voff, off + block_size);
 670                 }
 671         }
 672
 673         if (bh->b_size > bytes)
 674                 bh->b_size = bytes;
 675
 676 #ifndef __LP64__
 677         if (ctx == GET_BLOCK_DIRECT_IO_W || ctx == GET_BLOCK_DIRECT_IO_R) {
 678                 static_assert(sizeof(size_t) < sizeof(loff_t));
 679                 if (bytes > 0x40000000u)
 680                         bh->b_size = 0x40000000u;
 681         }
 682 #endif
 683
 684         return 0;
 685
 686 out:
 687         return err;
 688 }
 689
 690 int ntfs_get_block(struct inode *inode, sector_t vbn,
 691                    struct buffer_head *bh_result, int create)
 692 {
 693         return ntfs_get_block_vbo(inode, (u64)vbn << inode->i_blkbits,
 694                                   bh_result, create, GET_BLOCK_GENERAL);
 695 }
 696
 697 static int ntfs_get_block_bmap(struct inode *inode, sector_t vsn,
 698                                struct buffer_head *bh_result, int create)
 699 {
 700         return ntfs_get_block_vbo(inode,
 701                                   (u64)vsn << inode->i_sb->s_blocksize_bits,
 702                                   bh_result, create, GET_BLOCK_BMAP);
 703 }
 704
 705 static sector_t ntfs_bmap(struct address_space *mapping, sector_t block)
 706 {
 707         return generic_block_bmap(mapping, block, ntfs_get_block_bmap);
 708 }
 709
 710 static int ntfs_read_folio(struct file *file, struct folio *folio)
 711 {
 712         int err;
 713         struct address_space *mapping = folio->mapping;
 714         struct inode *inode = mapping->host;
 715         struct ntfs_inode *ni = ntfs_i(inode);
 716
 717         if (is_resident(ni)) {
 718                 ni_lock(ni);
 719                 err = attr_data_read_resident(ni, folio);
 720                 ni_unlock(ni);
 721                 if (err != E_NTFS_NONRESIDENT) {
 722                         folio_unlock(folio);
 723                         return err;
 724                 }
 725         }
 726
 727         if (is_compressed(ni)) {
 728                 ni_lock(ni);
 729                 err = ni_readpage_cmpr(ni, folio);
 730                 ni_unlock(ni);
 731                 return err;
 732         }
 733
 734         /* Normal + sparse files. */
 735         return mpage_read_folio(folio, ntfs_get_block);
 736 }
 737
 738 static void ntfs_readahead(struct readahead_control *rac)
 739 {
 740         struct address_space *mapping = rac->mapping;
 741         struct inode *inode = mapping->host;
 742         struct ntfs_inode *ni = ntfs_i(inode);
 743         u64 valid;
 744         loff_t pos;
 745
 746         if (is_resident(ni)) {
 747                 /* No readahead for resident. */
 748                 return;
 749         }
 750
 751         if (is_compressed(ni)) {
 752                 /* No readahead for compressed. */
 753                 return;
 754         }
 755
 756         valid = ni->i_valid;
 757         pos = readahead_pos(rac);
 758
 759         if (valid < i_size_read(inode) && pos <= valid &&
 760             valid < pos + readahead_length(rac)) {
 761                 /* Range cross 'valid'. Read it page by page. */
 762                 return;
 763         }
 764
 765         mpage_readahead(rac, ntfs_get_block);
 766 }
 767
 768 static int ntfs_get_block_direct_IO_R(struct inode *inode, sector_t iblock,
 769                                       struct buffer_head *bh_result, int create)
 770 {
 771         return ntfs_get_block_vbo(inode, (u64)iblock << inode->i_blkbits,
 772                                   bh_result, create, GET_BLOCK_DIRECT_IO_R);
 773 }
 774
 775 static int ntfs_get_block_direct_IO_W(struct inode *inode, sector_t iblock,
 776                                       struct buffer_head *bh_result, int create)
 777 {
 778         return ntfs_get_block_vbo(inode, (u64)iblock << inode->i_blkbits,
 779                                   bh_result, create, GET_BLOCK_DIRECT_IO_W);
 780 }
 781
 782 static ssize_t ntfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 783 {
 784         struct file *file = iocb->ki_filp;
 785         struct address_space *mapping = file->f_mapping;
 786         struct inode *inode = mapping->host;
 787         struct ntfs_inode *ni = ntfs_i(inode);
 788         loff_t vbo = iocb->ki_pos;
 789         loff_t end;
 790         int wr = iov_iter_rw(iter) & WRITE;
 791         size_t iter_count = iov_iter_count(iter);
 792         loff_t valid;
 793         ssize_t ret;
 794
 795         if (is_resident(ni)) {
 796                 /* Switch to buffered write. */
 797                 ret = 0;
 798                 goto out;
 799         }
 800
 801         ret = blockdev_direct_IO(iocb, inode, iter,
 802                                  wr ? ntfs_get_block_direct_IO_W :
 803                                       ntfs_get_block_direct_IO_R);
 804
 805         if (ret > 0)
 806                 end = vbo + ret;
 807         else if (wr && ret == -EIOCBQUEUED)
 808                 end = vbo + iter_count;
 809         else
 810                 goto out;
 811
 812         valid = ni->i_valid;
 813         if (wr) {
 814                 if (end > valid && !S_ISBLK(inode->i_mode)) {
 815                         ni->i_valid = end;
 816                         mark_inode_dirty(inode);
 817                 }
 818         } else if (vbo < valid && valid < end) {
 819                 /* Fix page. */
 820                 iov_iter_revert(iter, end - valid);
 821                 iov_iter_zero(end - valid, iter);
 822         }
 823
 824 out:
 825         return ret;
 826 }
 827
 828 int ntfs_set_size(struct inode *inode, u64 new_size)
 829 {
 830         struct super_block *sb = inode->i_sb;
 831         struct ntfs_sb_info *sbi = sb->s_fs_info;
 832         struct ntfs_inode *ni = ntfs_i(inode);
 833         int err;
 834
 835         /* Check for maximum file size. */
 836         if (is_sparsed(ni) || is_compressed(ni)) {
 837                 if (new_size > sbi->maxbytes_sparse) {
 838                         err = -EFBIG;
 839                         goto out;
 840                 }
 841         } else if (new_size > sbi->maxbytes) {
 842                 err = -EFBIG;
 843                 goto out;
 844         }
 845
 846         ni_lock(ni);
 847         down_write(&ni->file.run_lock);
 848
 849         err = attr_set_size(ni, ATTR_DATA, NULL, 0, &ni->file.run, new_size,
 850                             &ni->i_valid, true, NULL);
 851
 852         up_write(&ni->file.run_lock);
 853         ni_unlock(ni);
 854
 855         mark_inode_dirty(inode);
 856
 857 out:
 858         return err;
 859 }
 860
 861 static int ntfs_resident_writepage(struct folio *folio,
 862                                    struct writeback_control *wbc, void *data)
 863 {
 864         struct address_space *mapping = data;
 865         struct inode *inode = mapping->host;
 866         struct ntfs_inode *ni = ntfs_i(inode);
 867         int ret;
 868
 869         if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
 870                 return -EIO;
 871
 872         ni_lock(ni);
 873         ret = attr_data_write_resident(ni, folio);
 874         ni_unlock(ni);
 875
 876         if (ret != E_NTFS_NONRESIDENT)
 877                 folio_unlock(folio);
 878         mapping_set_error(mapping, ret);
 879         return ret;
 880 }
 881
 882 static int ntfs_writepages(struct address_space *mapping,
 883                            struct writeback_control *wbc)
 884 {
 885         struct inode *inode = mapping->host;
 886
 887         if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
 888                 return -EIO;
 889
 890         if (is_resident(ntfs_i(inode)))
 891                 return write_cache_pages(mapping, wbc, ntfs_resident_writepage,
 892                                          mapping);
 893         return mpage_writepages(mapping, wbc, ntfs_get_block);
 894 }
 895
 896 static int ntfs_get_block_write_begin(struct inode *inode, sector_t vbn,
 897                                       struct buffer_head *bh_result, int create)
 898 {
 899         return ntfs_get_block_vbo(inode, (u64)vbn << inode->i_blkbits,
 900                                   bh_result, create, GET_BLOCK_WRITE_BEGIN);
 901 }
 902
 903 int ntfs_write_begin(struct file *file, struct address_space *mapping,
 904                      loff_t pos, u32 len, struct page **pagep, void **fsdata)
 905 {
 906         int err;
 907         struct inode *inode = mapping->host;
 908         struct ntfs_inode *ni = ntfs_i(inode);
 909
 910         if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
 911                 return -EIO;
 912
 913         *pagep = NULL;
 914         if (is_resident(ni)) {
 915                 struct folio *folio = __filemap_get_folio(
 916                         mapping, pos >> PAGE_SHIFT, FGP_WRITEBEGIN,
 917                         mapping_gfp_mask(mapping));
 918
 919                 if (IS_ERR(folio)) {
 920                         err = PTR_ERR(folio);
 921                         goto out;
 922                 }
 923
 924                 ni_lock(ni);
 925                 err = attr_data_read_resident(ni, folio);
 926                 ni_unlock(ni);
 927
 928                 if (!err) {
 929                         *pagep = &folio->page;
 930                         goto out;
 931                 }
 932                 folio_unlock(folio);
 933                 folio_put(folio);
 934
 935                 if (err != E_NTFS_NONRESIDENT)
 936                         goto out;
 937         }
 938
 939         err = block_write_begin(mapping, pos, len, pagep,
 940                                 ntfs_get_block_write_begin);
 941
 942 out:
 943         return err;
 944 }
 945
 946 /*
 947  * ntfs_write_end - Address_space_operations::write_end.
 948  */
 949 int ntfs_write_end(struct file *file, struct address_space *mapping, loff_t pos,
 950                    u32 len, u32 copied, struct page *page, void *fsdata)
 951 {
 952         struct folio *folio = page_folio(page);
 953         struct inode *inode = mapping->host;
 954         struct ntfs_inode *ni = ntfs_i(inode);
 955         u64 valid = ni->i_valid;
 956         bool dirty = false;
 957         int err;
 958
 959         if (is_resident(ni)) {
 960                 ni_lock(ni);
 961                 err = attr_data_write_resident(ni, folio);
 962                 ni_unlock(ni);
 963                 if (!err) {
 964                         struct buffer_head *head = folio_buffers(folio);
 965                         dirty = true;
 966                         /* Clear any buffers in folio. */
 967                         if (head) {
 968                                 struct buffer_head *bh = head;
 969
 970                                 do {
 971                                         clear_buffer_dirty(bh);
 972                                         clear_buffer_mapped(bh);
 973                                         set_buffer_uptodate(bh);
 974                                 } while (head != (bh = bh->b_this_page));
 975                         }
 976                         folio_mark_uptodate(folio);
 977                         err = copied;
 978                 }
 979                 folio_unlock(folio);
 980                 folio_put(folio);
 981         } else {
 982                 err = generic_write_end(file, mapping, pos, len, copied, page,
 983                                         fsdata);
 984         }
 985
 986         if (err >= 0) {
 987                 if (!(ni->std_fa & FILE_ATTRIBUTE_ARCHIVE)) {
 988                         inode_set_mtime_to_ts(inode,
 989                                               inode_set_ctime_current(inode));
 990                         ni->std_fa |= FILE_ATTRIBUTE_ARCHIVE;
 991                         dirty = true;
 992                 }
 993
 994                 if (valid != ni->i_valid) {
 995                         /* ni->i_valid is changed in ntfs_get_block_vbo. */
 996                         dirty = true;
 997                 }
 998
 999                 if (pos + err > inode->i_size) {
1000                         i_size_write(inode, pos + err);
1001                         dirty = true;
1002                 }
1003
1004                 if (dirty)
1005                         mark_inode_dirty(inode);
1006         }
1007
1008         return err;
1009 }
1010
1011 int reset_log_file(struct inode *inode)
1012 {
1013         int err;
1014         loff_t pos = 0;
1015         u32 log_size = inode->i_size;
1016         struct address_space *mapping = inode->i_mapping;
1017
1018         for (;;) {
1019                 u32 len;
1020                 void *kaddr;
1021                 struct page *page;
1022
1023                 len = pos + PAGE_SIZE > log_size ? (log_size - pos) : PAGE_SIZE;
1024
1025                 err = block_write_begin(mapping, pos, len, &page,
1026                                         ntfs_get_block_write_begin);
1027                 if (err)
1028                         goto out;
1029
1030                 kaddr = kmap_atomic(page);
1031                 memset(kaddr, -1, len);
1032                 kunmap_atomic(kaddr);
1033                 flush_dcache_page(page);
1034
1035                 err = block_write_end(NULL, mapping, pos, len, len, page, NULL);
1036                 if (err < 0)
1037                         goto out;
1038                 pos += len;
1039
1040                 if (pos >= log_size)
1041                         break;
1042                 balance_dirty_pages_ratelimited(mapping);
1043         }
1044 out:
1045         mark_inode_dirty_sync(inode);
1046
1047         return err;
1048 }
1049
1050 int ntfs3_write_inode(struct inode *inode, struct writeback_control *wbc)
1051 {
1052         return _ni_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1053 }
1054
1055 int ntfs_sync_inode(struct inode *inode)
1056 {
1057         return _ni_write_inode(inode, 1);
1058 }
1059
1060 /*
1061  * writeback_inode - Helper function for ntfs_flush_inodes().
1062  *
1063  * This writes both the inode and the file data blocks, waiting
1064  * for in flight data blocks before the start of the call.  It
1065  * does not wait for any io started during the call.
1066  */
1067 static int writeback_inode(struct inode *inode)
1068 {
1069         int ret = sync_inode_metadata(inode, 0);
1070
1071         if (!ret)
1072                 ret = filemap_fdatawrite(inode->i_mapping);
1073         return ret;
1074 }
1075
1076 /*
1077  * ntfs_flush_inodes
1078  *
1079  * Write data and metadata corresponding to i1 and i2.  The io is
1080  * started but we do not wait for any of it to finish.
1081  *
1082  * filemap_flush() is used for the block device, so if there is a dirty
1083  * page for a block already in flight, we will not wait and start the
1084  * io over again.
1085  */
1086 int ntfs_flush_inodes(struct super_block *sb, struct inode *i1,
1087                       struct inode *i2)
1088 {
1089         int ret = 0;
1090
1091         if (i1)
1092                 ret = writeback_inode(i1);
1093         if (!ret && i2)
1094                 ret = writeback_inode(i2);
1095         if (!ret)
1096                 ret = filemap_flush(sb->s_bdev_file->f_mapping);
1097         return ret;
1098 }
1099
1100 /*
1101  * Helper function to read file.
1102  */
1103 int inode_read_data(struct inode *inode, void *data, size_t bytes)
1104 {
1105         pgoff_t idx;
1106         struct address_space *mapping = inode->i_mapping;
1107
1108         for (idx = 0; bytes; idx++) {
1109                 size_t op = bytes > PAGE_SIZE ? PAGE_SIZE : bytes;
1110                 struct page *page = read_mapping_page(mapping, idx, NULL);
1111                 void *kaddr;
1112
1113                 if (IS_ERR(page))
1114                         return PTR_ERR(page);
1115
1116                 kaddr = kmap_atomic(page);
1117                 memcpy(data, kaddr, op);
1118                 kunmap_atomic(kaddr);
1119
1120                 put_page(page);
1121
1122                 bytes -= op;
1123                 data = Add2Ptr(data, PAGE_SIZE);
1124         }
1125         return 0;
1126 }
1127
1128 /*
1129  * ntfs_reparse_bytes
1130  *
1131  * Number of bytes for REPARSE_DATA_BUFFER(IO_REPARSE_TAG_SYMLINK)
1132  * for unicode string of @uni_len length.
1133  */
1134 static inline u32 ntfs_reparse_bytes(u32 uni_len)
1135 {
1136         /* Header + unicode string + decorated unicode string. */
1137         return sizeof(short) * (2 * uni_len + 4) +
1138                offsetof(struct REPARSE_DATA_BUFFER,
1139                         SymbolicLinkReparseBuffer.PathBuffer);
1140 }
1141
1142 static struct REPARSE_DATA_BUFFER *
1143 ntfs_create_reparse_buffer(struct ntfs_sb_info *sbi, const char *symname,
1144                            u32 size, u16 *nsize)
1145 {
1146         int i, err;
1147         struct REPARSE_DATA_BUFFER *rp;
1148         __le16 *rp_name;
1149         typeof(rp->SymbolicLinkReparseBuffer) *rs;
1150
1151         rp = kzalloc(ntfs_reparse_bytes(2 * size + 2), GFP_NOFS);
1152         if (!rp)
1153                 return ERR_PTR(-ENOMEM);
1154
1155         rs = &rp->SymbolicLinkReparseBuffer;
1156         rp_name = rs->PathBuffer;
1157
1158         /* Convert link name to UTF-16. */
1159         err = ntfs_nls_to_utf16(sbi, symname, size,
1160                                 (struct cpu_str *)(rp_name - 1), 2 * size,
1161                                 UTF16_LITTLE_ENDIAN);
1162         if (err < 0)
1163                 goto out;
1164
1165         /* err = the length of unicode name of symlink. */
1166         *nsize = ntfs_reparse_bytes(err);
1167
1168         if (*nsize > sbi->reparse.max_size) {
1169                 err = -EFBIG;
1170                 goto out;
1171         }
1172
1173         /* Translate Linux '/' into Windows '\'. */
1174         for (i = 0; i < err; i++) {
1175                 if (rp_name[i] == cpu_to_le16('/'))
1176                         rp_name[i] = cpu_to_le16('\\');
1177         }
1178
1179         rp->ReparseTag = IO_REPARSE_TAG_SYMLINK;
1180         rp->ReparseDataLength =
1181                 cpu_to_le16(*nsize - offsetof(struct REPARSE_DATA_BUFFER,
1182                                               SymbolicLinkReparseBuffer));
1183
1184         /* PrintName + SubstituteName. */
1185         rs->SubstituteNameOffset = cpu_to_le16(sizeof(short) * err);
1186         rs->SubstituteNameLength = cpu_to_le16(sizeof(short) * err + 8);
1187         rs->PrintNameLength = rs->SubstituteNameOffset;
1188
1189         /*
1190          * TODO: Use relative path if possible to allow Windows to
1191          * parse this path.
1192          * 0-absolute path 1- relative path (SYMLINK_FLAG_RELATIVE).
1193          */
1194         rs->Flags = 0;
1195
1196         memmove(rp_name + err + 4, rp_name, sizeof(short) * err);
1197
1198         /* Decorate SubstituteName. */
1199         rp_name += err;
1200         rp_name[0] = cpu_to_le16('\\');
1201         rp_name[1] = cpu_to_le16('?');
1202         rp_name[2] = cpu_to_le16('?');
1203         rp_name[3] = cpu_to_le16('\\');
1204
1205         return rp;
1206 out:
1207         kfree(rp);
1208         return ERR_PTR(err);
1209 }
1210
1211 /*
1212  * ntfs_create_inode
1213  *
1214  * Helper function for:
1215  * - ntfs_create
1216  * - ntfs_mknod
1217  * - ntfs_symlink
1218  * - ntfs_mkdir
1219  * - ntfs_atomic_open
1220  *
1221  * NOTE: if fnd != NULL (ntfs_atomic_open) then @dir is locked
1222  */
1223 int ntfs_create_inode(struct mnt_idmap *idmap, struct inode *dir,
1224                       struct dentry *dentry, const struct cpu_str *uni,
1225                       umode_t mode, dev_t dev, const char *symname, u32 size,
1226                       struct ntfs_fnd *fnd)
1227 {
1228         int err;
1229         struct super_block *sb = dir->i_sb;
1230         struct ntfs_sb_info *sbi = sb->s_fs_info;
1231         const struct qstr *name = &dentry->d_name;
1232         CLST ino = 0;
1233         struct ntfs_inode *dir_ni = ntfs_i(dir);
1234         struct ntfs_inode *ni = NULL;
1235         struct inode *inode = NULL;
1236         struct ATTRIB *attr;
1237         struct ATTR_STD_INFO5 *std5;
1238         struct ATTR_FILE_NAME *fname;
1239         struct MFT_REC *rec;
1240         u32 asize, dsize, sd_size;
1241         enum FILE_ATTRIBUTE fa;
1242         __le32 security_id = SECURITY_ID_INVALID;
1243         CLST vcn;
1244         const void *sd;
1245         u16 t16, nsize = 0, aid = 0;
1246         struct INDEX_ROOT *root, *dir_root;
1247         struct NTFS_DE *e, *new_de = NULL;
1248         struct REPARSE_DATA_BUFFER *rp = NULL;
1249         bool rp_inserted = false;
1250
1251         /* New file will be resident or non resident. */
1252         const bool new_file_resident = 1;
1253
1254         if (!fnd)
1255                 ni_lock_dir(dir_ni);
1256
1257         dir_root = indx_get_root(&dir_ni->dir, dir_ni, NULL, NULL);
1258         if (!dir_root) {
1259                 err = -EINVAL;
1260                 goto out1;
1261         }
1262
1263         if (S_ISDIR(mode)) {
1264                 /* Use parent's directory attributes. */
1265                 fa = dir_ni->std_fa | FILE_ATTRIBUTE_DIRECTORY |
1266                      FILE_ATTRIBUTE_ARCHIVE;
1267                 /*
1268                  * By default child directory inherits parent attributes.
1269                  * Root directory is hidden + system.
1270                  * Make an exception for children in root.
1271                  */
1272                 if (dir->i_ino == MFT_REC_ROOT)
1273                         fa &= ~(FILE_ATTRIBUTE_HIDDEN | FILE_ATTRIBUTE_SYSTEM);
1274         } else if (S_ISLNK(mode)) {
1275                 /* It is good idea that link should be the same type (file/dir) as target */
1276                 fa = FILE_ATTRIBUTE_REPARSE_POINT;
1277
1278                 /*
1279                  * Linux: there are dir/file/symlink and so on.
1280                  * NTFS: symlinks are "dir + reparse" or "file + reparse"
1281                  * It is good idea to create:
1282                  * dir + reparse if 'symname' points to directory
1283                  * or
1284                  * file + reparse if 'symname' points to file
1285                  * Unfortunately kern_path hangs if symname contains 'dir'.
1286                  */
1287
1288                 /*
1289                  *      struct path path;
1290                  *
1291                  *      if (!kern_path(symname, LOOKUP_FOLLOW, &path)){
1292                  *              struct inode *target = d_inode(path.dentry);
1293                  *
1294                  *              if (S_ISDIR(target->i_mode))
1295                  *                      fa |= FILE_ATTRIBUTE_DIRECTORY;
1296                  *              // if ( target->i_sb == sb ){
1297                  *              //      use relative path?
1298                  *              // }
1299                  *              path_put(&path);
1300                  *      }
1301                  */
1302         } else if (S_ISREG(mode)) {
1303                 if (sbi->options->sparse) {
1304                         /* Sparsed regular file, cause option 'sparse'. */
1305                         fa = FILE_ATTRIBUTE_SPARSE_FILE |
1306                              FILE_ATTRIBUTE_ARCHIVE;
1307                 } else if (dir_ni->std_fa & FILE_ATTRIBUTE_COMPRESSED) {
1308                         /* Compressed regular file, if parent is compressed. */
1309                         fa = FILE_ATTRIBUTE_COMPRESSED | FILE_ATTRIBUTE_ARCHIVE;
1310                 } else {
1311                         /* Regular file, default attributes. */
1312                         fa = FILE_ATTRIBUTE_ARCHIVE;
1313                 }
1314         } else {
1315                 fa = FILE_ATTRIBUTE_ARCHIVE;
1316         }
1317
1318         /* If option "hide_dot_files" then set hidden attribute for dot files. */
1319         if (sbi->options->hide_dot_files && name->name[0] == '.')
1320                 fa |= FILE_ATTRIBUTE_HIDDEN;
1321
1322         if (!(mode & 0222))
1323                 fa |= FILE_ATTRIBUTE_READONLY;
1324
1325         /* Allocate PATH_MAX bytes. */
1326         new_de = __getname();
1327         if (!new_de) {
1328                 err = -ENOMEM;
1329                 goto out1;
1330         }
1331
1332         if (unlikely(ntfs3_forced_shutdown(sb))) {
1333                 err = -EIO;
1334                 goto out2;
1335         }
1336
1337         /* Mark rw ntfs as dirty. it will be cleared at umount. */
1338         ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
1339
1340         /* Step 1: allocate and fill new mft record. */
1341         err = ntfs_look_free_mft(sbi, &ino, false, NULL, NULL);
1342         if (err)
1343                 goto out2;
1344
1345         ni = ntfs_new_inode(sbi, ino, S_ISDIR(mode) ? RECORD_FLAG_DIR : 0);
1346         if (IS_ERR(ni)) {
1347                 err = PTR_ERR(ni);
1348                 ni = NULL;
1349                 goto out3;
1350         }
1351         inode = &ni->vfs_inode;
1352         inode_init_owner(idmap, inode, dir, mode);
1353         mode = inode->i_mode;
1354
1355         ni->i_crtime = current_time(inode);
1356
1357         rec = ni->mi.mrec;
1358         rec->hard_links = cpu_to_le16(1);
1359         attr = Add2Ptr(rec, le16_to_cpu(rec->attr_off));
1360
1361         /* Get default security id. */
1362         sd = s_default_security;
1363         sd_size = sizeof(s_default_security);
1364
1365         if (is_ntfs3(sbi)) {
1366                 security_id = dir_ni->std_security_id;
1367                 if (le32_to_cpu(security_id) < SECURITY_ID_FIRST) {
1368                         security_id = sbi->security.def_security_id;
1369
1370                         if (security_id == SECURITY_ID_INVALID &&
1371                             !ntfs_insert_security(sbi, sd, sd_size,
1372                                                   &security_id, NULL))
1373                                 sbi->security.def_security_id = security_id;
1374                 }
1375         }
1376
1377         /* Insert standard info. */
1378         std5 = Add2Ptr(attr, SIZEOF_RESIDENT);
1379
1380         if (security_id == SECURITY_ID_INVALID) {
1381                 dsize = sizeof(struct ATTR_STD_INFO);
1382         } else {
1383                 dsize = sizeof(struct ATTR_STD_INFO5);
1384                 std5->security_id = security_id;
1385                 ni->std_security_id = security_id;
1386         }
1387         asize = SIZEOF_RESIDENT + dsize;
1388
1389         attr->type = ATTR_STD;
1390         attr->size = cpu_to_le32(asize);
1391         attr->id = cpu_to_le16(aid++);
1392         attr->res.data_off = SIZEOF_RESIDENT_LE;
1393         attr->res.data_size = cpu_to_le32(dsize);
1394
1395         std5->cr_time = std5->m_time = std5->c_time = std5->a_time =
1396                 kernel2nt(&ni->i_crtime);
1397
1398         std5->fa = ni->std_fa = fa;
1399
1400         attr = Add2Ptr(attr, asize);
1401
1402         /* Insert file name. */
1403         err = fill_name_de(sbi, new_de, name, uni);
1404         if (err)
1405                 goto out4;
1406
1407         mi_get_ref(&ni->mi, &new_de->ref);
1408
1409         fname = (struct ATTR_FILE_NAME *)(new_de + 1);
1410
1411         if (sbi->options->windows_names &&
1412             !valid_windows_name(sbi, (struct le_str *)&fname->name_len)) {
1413                 err = -EINVAL;
1414                 goto out4;
1415         }
1416
1417         mi_get_ref(&dir_ni->mi, &fname->home);
1418         fname->dup.cr_time = fname->dup.m_time = fname->dup.c_time =
1419                 fname->dup.a_time = std5->cr_time;
1420         fname->dup.alloc_size = fname->dup.data_size = 0;
1421         fname->dup.fa = std5->fa;
1422         fname->dup.ea_size = fname->dup.reparse = 0;
1423
1424         dsize = le16_to_cpu(new_de->key_size);
1425         asize = ALIGN(SIZEOF_RESIDENT + dsize, 8);
1426
1427         attr->type = ATTR_NAME;
1428         attr->size = cpu_to_le32(asize);
1429         attr->res.data_off = SIZEOF_RESIDENT_LE;
1430         attr->res.flags = RESIDENT_FLAG_INDEXED;
1431         attr->id = cpu_to_le16(aid++);
1432         attr->res.data_size = cpu_to_le32(dsize);
1433         memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), fname, dsize);
1434
1435         attr = Add2Ptr(attr, asize);
1436
1437         if (security_id == SECURITY_ID_INVALID) {
1438                 /* Insert security attribute. */
1439                 asize = SIZEOF_RESIDENT + ALIGN(sd_size, 8);
1440
1441                 attr->type = ATTR_SECURE;
1442                 attr->size = cpu_to_le32(asize);
1443                 attr->id = cpu_to_le16(aid++);
1444                 attr->res.data_off = SIZEOF_RESIDENT_LE;
1445                 attr->res.data_size = cpu_to_le32(sd_size);
1446                 memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), sd, sd_size);
1447
1448                 attr = Add2Ptr(attr, asize);
1449         }
1450
1451         attr->id = cpu_to_le16(aid++);
1452         if (fa & FILE_ATTRIBUTE_DIRECTORY) {
1453                 /*
1454                  * Regular directory or symlink to directory.
1455                  * Create root attribute.
1456                  */
1457                 dsize = sizeof(struct INDEX_ROOT) + sizeof(struct NTFS_DE);
1458                 asize = sizeof(I30_NAME) + SIZEOF_RESIDENT + dsize;
1459
1460                 attr->type = ATTR_ROOT;
1461                 attr->size = cpu_to_le32(asize);
1462
1463                 attr->name_len = ARRAY_SIZE(I30_NAME);
1464                 attr->name_off = SIZEOF_RESIDENT_LE;
1465                 attr->res.data_off =
1466                         cpu_to_le16(sizeof(I30_NAME) + SIZEOF_RESIDENT);
1467                 attr->res.data_size = cpu_to_le32(dsize);
1468                 memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), I30_NAME,
1469                        sizeof(I30_NAME));
1470
1471                 root = Add2Ptr(attr, sizeof(I30_NAME) + SIZEOF_RESIDENT);
1472                 memcpy(root, dir_root, offsetof(struct INDEX_ROOT, ihdr));
1473                 root->ihdr.de_off = cpu_to_le32(sizeof(struct INDEX_HDR));
1474                 root->ihdr.used = cpu_to_le32(sizeof(struct INDEX_HDR) +
1475                                               sizeof(struct NTFS_DE));
1476                 root->ihdr.total = root->ihdr.used;
1477
1478                 e = Add2Ptr(root, sizeof(struct INDEX_ROOT));
1479                 e->size = cpu_to_le16(sizeof(struct NTFS_DE));
1480                 e->flags = NTFS_IE_LAST;
1481         } else if (S_ISLNK(mode)) {
1482                 /*
1483                  * Symlink to file.
1484                  * Create empty resident data attribute.
1485                  */
1486                 asize = SIZEOF_RESIDENT;
1487
1488                 /* Insert empty ATTR_DATA */
1489                 attr->type = ATTR_DATA;
1490                 attr->size = cpu_to_le32(SIZEOF_RESIDENT);
1491                 attr->name_off = SIZEOF_RESIDENT_LE;
1492                 attr->res.data_off = SIZEOF_RESIDENT_LE;
1493         } else if (!new_file_resident && S_ISREG(mode)) {
1494                 /*
1495                  * Regular file. Create empty non resident data attribute.
1496                  */
1497                 attr->type = ATTR_DATA;
1498                 attr->non_res = 1;
1499                 attr->nres.evcn = cpu_to_le64(-1ll);
1500                 if (fa & FILE_ATTRIBUTE_SPARSE_FILE) {
1501                         attr->size = cpu_to_le32(SIZEOF_NONRESIDENT_EX + 8);
1502                         attr->name_off = SIZEOF_NONRESIDENT_EX_LE;
1503                         attr->flags = ATTR_FLAG_SPARSED;
1504                         asize = SIZEOF_NONRESIDENT_EX + 8;
1505                 } else if (fa & FILE_ATTRIBUTE_COMPRESSED) {
1506                         attr->size = cpu_to_le32(SIZEOF_NONRESIDENT_EX + 8);
1507                         attr->name_off = SIZEOF_NONRESIDENT_EX_LE;
1508                         attr->flags = ATTR_FLAG_COMPRESSED;
1509                         attr->nres.c_unit = NTFS_LZNT_CUNIT;
1510                         asize = SIZEOF_NONRESIDENT_EX + 8;
1511                 } else {
1512                         attr->size = cpu_to_le32(SIZEOF_NONRESIDENT + 8);
1513                         attr->name_off = SIZEOF_NONRESIDENT_LE;
1514                         asize = SIZEOF_NONRESIDENT + 8;
1515                 }
1516                 attr->nres.run_off = attr->name_off;
1517         } else {
1518                 /*
1519                  * Node. Create empty resident data attribute.
1520                  */
1521                 attr->type = ATTR_DATA;
1522                 attr->size = cpu_to_le32(SIZEOF_RESIDENT);
1523                 attr->name_off = SIZEOF_RESIDENT_LE;
1524                 if (fa & FILE_ATTRIBUTE_SPARSE_FILE)
1525                         attr->flags = ATTR_FLAG_SPARSED;
1526                 else if (fa & FILE_ATTRIBUTE_COMPRESSED)
1527                         attr->flags = ATTR_FLAG_COMPRESSED;
1528                 attr->res.data_off = SIZEOF_RESIDENT_LE;
1529                 asize = SIZEOF_RESIDENT;
1530                 ni->ni_flags |= NI_FLAG_RESIDENT;
1531         }
1532
1533         if (S_ISDIR(mode)) {
1534                 ni->ni_flags |= NI_FLAG_DIR;
1535                 err = indx_init(&ni->dir, sbi, attr, INDEX_MUTEX_I30);
1536                 if (err)
1537                         goto out4;
1538         } else if (S_ISLNK(mode)) {
1539                 rp = ntfs_create_reparse_buffer(sbi, symname, size, &nsize);
1540
1541                 if (IS_ERR(rp)) {
1542                         err = PTR_ERR(rp);
1543                         rp = NULL;
1544                         goto out4;
1545                 }
1546
1547                 /*
1548                  * Insert ATTR_REPARSE.
1549                  */
1550                 attr = Add2Ptr(attr, asize);
1551                 attr->type = ATTR_REPARSE;
1552                 attr->id = cpu_to_le16(aid++);
1553
1554                 /* Resident or non resident? */
1555                 asize = ALIGN(SIZEOF_RESIDENT + nsize, 8);
1556                 t16 = PtrOffset(rec, attr);
1557
1558                 /*
1559                  * Below function 'ntfs_save_wsl_perm' requires 0x78 bytes.
1560                  * It is good idea to keep extended attributes resident.
1561                  */
1562                 if (asize + t16 + 0x78 + 8 > sbi->record_size) {
1563                         CLST alen;
1564                         CLST clst = bytes_to_cluster(sbi, nsize);
1565
1566                         /* Bytes per runs. */
1567                         t16 = sbi->record_size - t16 - SIZEOF_NONRESIDENT;
1568
1569                         attr->non_res = 1;
1570                         attr->nres.evcn = cpu_to_le64(clst - 1);
1571                         attr->name_off = SIZEOF_NONRESIDENT_LE;
1572                         attr->nres.run_off = attr->name_off;
1573                         attr->nres.data_size = cpu_to_le64(nsize);
1574                         attr->nres.valid_size = attr->nres.data_size;
1575                         attr->nres.alloc_size =
1576                                 cpu_to_le64(ntfs_up_cluster(sbi, nsize));
1577
1578                         err = attr_allocate_clusters(sbi, &ni->file.run, 0, 0,
1579                                                      clst, NULL, ALLOCATE_DEF,
1580                                                      &alen, 0, NULL, NULL);
1581                         if (err)
1582                                 goto out5;
1583
1584                         err = run_pack(&ni->file.run, 0, clst,
1585                                        Add2Ptr(attr, SIZEOF_NONRESIDENT), t16,
1586                                        &vcn);
1587                         if (err < 0)
1588                                 goto out5;
1589
1590                         if (vcn != clst) {
1591                                 err = -EINVAL;
1592                                 goto out5;
1593                         }
1594
1595                         asize = SIZEOF_NONRESIDENT + ALIGN(err, 8);
1596                         /* Write non resident data. */
1597                         err = ntfs_sb_write_run(sbi, &ni->file.run, 0, rp,
1598                                                 nsize, 0);
1599                         if (err)
1600                                 goto out5;
1601                 } else {
1602                         attr->res.data_off = SIZEOF_RESIDENT_LE;
1603                         attr->res.data_size = cpu_to_le32(nsize);
1604                         memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), rp, nsize);
1605                 }
1606                 /* Size of symlink equals the length of input string. */
1607                 inode->i_size = size;
1608
1609                 attr->size = cpu_to_le32(asize);
1610
1611                 err = ntfs_insert_reparse(sbi, IO_REPARSE_TAG_SYMLINK,
1612                                           &new_de->ref);
1613                 if (err)
1614                         goto out5;
1615
1616                 rp_inserted = true;
1617         }
1618
1619         attr = Add2Ptr(attr, asize);
1620         attr->type = ATTR_END;
1621
1622         rec->used = cpu_to_le32(PtrOffset(rec, attr) + 8);
1623         rec->next_attr_id = cpu_to_le16(aid);
1624
1625         inode->i_generation = le16_to_cpu(rec->seq);
1626
1627         if (S_ISDIR(mode)) {
1628                 inode->i_op = &ntfs_dir_inode_operations;
1629                 inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
1630                                        &ntfs_legacy_dir_operations :
1631                                        &ntfs_dir_operations;
1632         } else if (S_ISLNK(mode)) {
1633                 inode->i_op = &ntfs_link_inode_operations;
1634                 inode->i_fop = NULL;
1635                 inode->i_mapping->a_ops = &ntfs_aops;
1636                 inode->i_size = size;
1637                 inode_nohighmem(inode);
1638         } else if (S_ISREG(mode)) {
1639                 inode->i_op = &ntfs_file_inode_operations;
1640                 inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
1641                                        &ntfs_legacy_file_operations :
1642                                        &ntfs_file_operations;
1643                 inode->i_mapping->a_ops = is_compressed(ni) ? &ntfs_aops_cmpr :
1644                                                               &ntfs_aops;
1645                 init_rwsem(&ni->file.run_lock);
1646         } else {
1647                 inode->i_op = &ntfs_special_inode_operations;
1648                 init_special_inode(inode, mode, dev);
1649         }
1650
1651 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
1652         if (!S_ISLNK(mode) && (sb->s_flags & SB_POSIXACL)) {
1653                 err = ntfs_init_acl(idmap, inode, dir);
1654                 if (err)
1655                         goto out5;
1656         } else
1657 #endif
1658         {
1659                 inode->i_flags |= S_NOSEC;
1660         }
1661
1662         /*
1663          * ntfs_init_acl and ntfs_save_wsl_perm update extended attribute.
1664          * The packed size of extended attribute is stored in direntry too.
1665          * 'fname' here points to inside new_de.
1666          */
1667         err = ntfs_save_wsl_perm(inode, &fname->dup.ea_size);
1668         if (err)
1669                 goto out6;
1670
1671         /*
1672          * update ea_size in file_name attribute too.
1673          * Use ni_find_attr cause layout of MFT record may be changed
1674          * in ntfs_init_acl and ntfs_save_wsl_perm.
1675          */
1676         attr = ni_find_attr(ni, NULL, NULL, ATTR_NAME, NULL, 0, NULL, NULL);
1677         if (attr) {
1678                 struct ATTR_FILE_NAME *fn;
1679
1680                 fn = resident_data_ex(attr, SIZEOF_ATTRIBUTE_FILENAME);
1681                 if (fn)
1682                         fn->dup.ea_size = fname->dup.ea_size;
1683         }
1684
1685         /* We do not need to update parent directory later */
1686         ni->ni_flags &= ~NI_FLAG_UPDATE_PARENT;
1687
1688         /* Step 2: Add new name in index. */
1689         err = indx_insert_entry(&dir_ni->dir, dir_ni, new_de, sbi, fnd, 0);
1690         if (err)
1691                 goto out6;
1692
1693         /*
1694          * Call 'd_instantiate' after inode->i_op is set
1695          * but before finish_open.
1696          */
1697         d_instantiate(dentry, inode);
1698
1699         /* Set original time. inode times (i_ctime) may be changed in ntfs_init_acl. */
1700         inode_set_atime_to_ts(inode, ni->i_crtime);
1701         inode_set_ctime_to_ts(inode, ni->i_crtime);
1702         inode_set_mtime_to_ts(inode, ni->i_crtime);
1703         inode_set_mtime_to_ts(dir, ni->i_crtime);
1704         inode_set_ctime_to_ts(dir, ni->i_crtime);
1705
1706         mark_inode_dirty(dir);
1707         mark_inode_dirty(inode);
1708
1709         /* Normal exit. */
1710         goto out2;
1711
1712 out6:
1713         attr = ni_find_attr(ni, NULL, NULL, ATTR_EA, NULL, 0, NULL, NULL);
1714         if (attr && attr->non_res) {
1715                 /* Delete ATTR_EA, if non-resident. */
1716                 attr_set_size(ni, ATTR_EA, NULL, 0, NULL, 0, NULL, false, NULL);
1717         }
1718
1719         if (rp_inserted)
1720                 ntfs_remove_reparse(sbi, IO_REPARSE_TAG_SYMLINK, &new_de->ref);
1721
1722 out5:
1723         if (!S_ISDIR(mode))
1724                 run_deallocate(sbi, &ni->file.run, false);
1725
1726 out4:
1727         clear_rec_inuse(rec);
1728         clear_nlink(inode);
1729         ni->mi.dirty = false;
1730         discard_new_inode(inode);
1731 out3:
1732         ntfs_mark_rec_free(sbi, ino, false);
1733
1734 out2:
1735         __putname(new_de);
1736         kfree(rp);
1737
1738 out1:
1739         if (!fnd)
1740                 ni_unlock(dir_ni);
1741
1742         if (!err)
1743                 unlock_new_inode(inode);
1744
1745         return err;
1746 }
1747
1748 int ntfs_link_inode(struct inode *inode, struct dentry *dentry)
1749 {
1750         int err;
1751         struct ntfs_inode *ni = ntfs_i(inode);
1752         struct ntfs_sb_info *sbi = inode->i_sb->s_fs_info;
1753         struct NTFS_DE *de;
1754
1755         /* Allocate PATH_MAX bytes. */
1756         de = __getname();
1757         if (!de)
1758                 return -ENOMEM;
1759
1760         /* Mark rw ntfs as dirty. It will be cleared at umount. */
1761         ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
1762
1763         /* Construct 'de'. */
1764         err = fill_name_de(sbi, de, &dentry->d_name, NULL);
1765         if (err)
1766                 goto out;
1767
1768         err = ni_add_name(ntfs_i(d_inode(dentry->d_parent)), ni, de);
1769 out:
1770         __putname(de);
1771         return err;
1772 }
1773
1774 /*
1775  * ntfs_unlink_inode
1776  *
1777  * inode_operations::unlink
1778  * inode_operations::rmdir
1779  */
1780 int ntfs_unlink_inode(struct inode *dir, const struct dentry *dentry)
1781 {
1782         int err;
1783         struct ntfs_sb_info *sbi = dir->i_sb->s_fs_info;
1784         struct inode *inode = d_inode(dentry);
1785         struct ntfs_inode *ni = ntfs_i(inode);
1786         struct ntfs_inode *dir_ni = ntfs_i(dir);
1787         struct NTFS_DE *de, *de2 = NULL;
1788         int undo_remove;
1789
1790         if (ntfs_is_meta_file(sbi, ni->mi.rno))
1791                 return -EINVAL;
1792
1793         /* Allocate PATH_MAX bytes. */
1794         de = __getname();
1795         if (!de)
1796                 return -ENOMEM;
1797
1798         ni_lock(ni);
1799
1800         if (S_ISDIR(inode->i_mode) && !dir_is_empty(inode)) {
1801                 err = -ENOTEMPTY;
1802                 goto out;
1803         }
1804
1805         err = fill_name_de(sbi, de, &dentry->d_name, NULL);
1806         if (err < 0)
1807                 goto out;
1808
1809         undo_remove = 0;
1810         err = ni_remove_name(dir_ni, ni, de, &de2, &undo_remove);
1811
1812         if (!err) {
1813                 drop_nlink(inode);
1814                 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
1815                 mark_inode_dirty(dir);
1816                 inode_set_ctime_to_ts(inode, inode_get_ctime(dir));
1817                 if (inode->i_nlink)
1818                         mark_inode_dirty(inode);
1819         } else if (!ni_remove_name_undo(dir_ni, ni, de, de2, undo_remove)) {
1820                 _ntfs_bad_inode(inode);
1821         } else {
1822                 if (ni_is_dirty(dir))
1823                         mark_inode_dirty(dir);
1824                 if (ni_is_dirty(inode))
1825                         mark_inode_dirty(inode);
1826         }
1827
1828 out:
1829         ni_unlock(ni);
1830         __putname(de);
1831         return err;
1832 }
1833
1834 void ntfs_evict_inode(struct inode *inode)
1835 {
1836         truncate_inode_pages_final(&inode->i_data);
1837
1838         invalidate_inode_buffers(inode);
1839         clear_inode(inode);
1840
1841         ni_clear(ntfs_i(inode));
1842 }
1843
1844 /*
1845  * ntfs_translate_junction
1846  *
1847  * Translate a Windows junction target to the Linux equivalent.
1848  * On junctions, targets are always absolute (they include the drive
1849  * letter). We have no way of knowing if the target is for the current
1850  * mounted device or not so we just assume it is.
1851  */
1852 static int ntfs_translate_junction(const struct super_block *sb,
1853                                    const struct dentry *link_de, char *target,
1854                                    int target_len, int target_max)
1855 {
1856         int tl_len, err = target_len;
1857         char *link_path_buffer = NULL, *link_path;
1858         char *translated = NULL;
1859         char *target_start;
1860         int copy_len;
1861
1862         link_path_buffer = kmalloc(PATH_MAX, GFP_NOFS);
1863         if (!link_path_buffer) {
1864                 err = -ENOMEM;
1865                 goto out;
1866         }
1867         /* Get link path, relative to mount point */
1868         link_path = dentry_path_raw(link_de, link_path_buffer, PATH_MAX);
1869         if (IS_ERR(link_path)) {
1870                 ntfs_err(sb, "Error getting link path");
1871                 err = -EINVAL;
1872                 goto out;
1873         }
1874
1875         translated = kmalloc(PATH_MAX, GFP_NOFS);
1876         if (!translated) {
1877                 err = -ENOMEM;
1878                 goto out;
1879         }
1880
1881         /* Make translated path a relative path to mount point */
1882         strcpy(translated, "./");
1883         ++link_path; /* Skip leading / */
1884         for (tl_len = sizeof("./") - 1; *link_path; ++link_path) {
1885                 if (*link_path == '/') {
1886                         if (PATH_MAX - tl_len < sizeof("../")) {
1887                                 ntfs_err(sb,
1888                                          "Link path %s has too many components",
1889                                          link_path);
1890                                 err = -EINVAL;
1891                                 goto out;
1892                         }
1893                         strcpy(translated + tl_len, "../");
1894                         tl_len += sizeof("../") - 1;
1895                 }
1896         }
1897
1898         /* Skip drive letter */
1899         target_start = target;
1900         while (*target_start && *target_start != ':')
1901                 ++target_start;
1902
1903         if (!*target_start) {
1904                 ntfs_err(sb, "Link target (%s) missing drive separator",
1905                          target);
1906                 err = -EINVAL;
1907                 goto out;
1908         }
1909
1910         /* Skip drive separator and leading /, if exists */
1911         target_start += 1 + (target_start[1] == '/');
1912         copy_len = target_len - (target_start - target);
1913
1914         if (PATH_MAX - tl_len <= copy_len) {
1915                 ntfs_err(sb, "Link target %s too large for buffer (%d <= %d)",
1916                          target_start, PATH_MAX - tl_len, copy_len);
1917                 err = -EINVAL;
1918                 goto out;
1919         }
1920
1921         /* translated path has a trailing / and target_start does not */
1922         strcpy(translated + tl_len, target_start);
1923         tl_len += copy_len;
1924         if (target_max <= tl_len) {
1925                 ntfs_err(sb, "Target path %s too large for buffer (%d <= %d)",
1926                          translated, target_max, tl_len);
1927                 err = -EINVAL;
1928                 goto out;
1929         }
1930         strcpy(target, translated);
1931         err = tl_len;
1932
1933 out:
1934         kfree(link_path_buffer);
1935         kfree(translated);
1936         return err;
1937 }
1938
1939 static noinline int ntfs_readlink_hlp(const struct dentry *link_de,
1940                                       struct inode *inode, char *buffer,
1941                                       int buflen)
1942 {
1943         int i, err = -EINVAL;
1944         struct ntfs_inode *ni = ntfs_i(inode);
1945         struct super_block *sb = inode->i_sb;
1946         struct ntfs_sb_info *sbi = sb->s_fs_info;
1947         u64 size;
1948         u16 ulen = 0;
1949         void *to_free = NULL;
1950         struct REPARSE_DATA_BUFFER *rp;
1951         const __le16 *uname;
1952         struct ATTRIB *attr;
1953
1954         /* Reparse data present. Try to parse it. */
1955         static_assert(!offsetof(struct REPARSE_DATA_BUFFER, ReparseTag));
1956         static_assert(sizeof(u32) == sizeof(rp->ReparseTag));
1957
1958         *buffer = 0;
1959
1960         attr = ni_find_attr(ni, NULL, NULL, ATTR_REPARSE, NULL, 0, NULL, NULL);
1961         if (!attr)
1962                 goto out;
1963
1964         if (!attr->non_res) {
1965                 rp = resident_data_ex(attr, sizeof(struct REPARSE_DATA_BUFFER));
1966                 if (!rp)
1967                         goto out;
1968                 size = le32_to_cpu(attr->res.data_size);
1969         } else {
1970                 size = le64_to_cpu(attr->nres.data_size);
1971                 rp = NULL;
1972         }
1973
1974         if (size > sbi->reparse.max_size || size <= sizeof(u32))
1975                 goto out;
1976
1977         if (!rp) {
1978                 rp = kmalloc(size, GFP_NOFS);
1979                 if (!rp) {
1980                         err = -ENOMEM;
1981                         goto out;
1982                 }
1983                 to_free = rp;
1984                 /* Read into temporal buffer. */
1985                 err = ntfs_read_run_nb(sbi, &ni->file.run, 0, rp, size, NULL);
1986                 if (err)
1987                         goto out;
1988         }
1989
1990         /* Microsoft Tag. */
1991         switch (rp->ReparseTag) {
1992         case IO_REPARSE_TAG_MOUNT_POINT:
1993                 /* Mount points and junctions. */
1994                 /* Can we use 'Rp->MountPointReparseBuffer.PrintNameLength'? */
1995                 if (size <= offsetof(struct REPARSE_DATA_BUFFER,
1996                                      MountPointReparseBuffer.PathBuffer))
1997                         goto out;
1998                 uname = Add2Ptr(rp,
1999                                 offsetof(struct REPARSE_DATA_BUFFER,
2000                                          MountPointReparseBuffer.PathBuffer) +
2001                                         le16_to_cpu(rp->MountPointReparseBuffer
2002                                                             .PrintNameOffset));
2003                 ulen = le16_to_cpu(rp->MountPointReparseBuffer.PrintNameLength);
2004                 break;
2005
2006         case IO_REPARSE_TAG_SYMLINK:
2007                 /* FolderSymbolicLink */
2008                 /* Can we use 'Rp->SymbolicLinkReparseBuffer.PrintNameLength'? */
2009                 if (size <= offsetof(struct REPARSE_DATA_BUFFER,
2010                                      SymbolicLinkReparseBuffer.PathBuffer))
2011                         goto out;
2012                 uname = Add2Ptr(
2013                         rp, offsetof(struct REPARSE_DATA_BUFFER,
2014                                      SymbolicLinkReparseBuffer.PathBuffer) +
2015                                     le16_to_cpu(rp->SymbolicLinkReparseBuffer
2016                                                         .PrintNameOffset));
2017                 ulen = le16_to_cpu(
2018                         rp->SymbolicLinkReparseBuffer.PrintNameLength);
2019                 break;
2020
2021         case IO_REPARSE_TAG_CLOUD:
2022         case IO_REPARSE_TAG_CLOUD_1:
2023         case IO_REPARSE_TAG_CLOUD_2:
2024         case IO_REPARSE_TAG_CLOUD_3:
2025         case IO_REPARSE_TAG_CLOUD_4:
2026         case IO_REPARSE_TAG_CLOUD_5:
2027         case IO_REPARSE_TAG_CLOUD_6:
2028         case IO_REPARSE_TAG_CLOUD_7:
2029         case IO_REPARSE_TAG_CLOUD_8:
2030         case IO_REPARSE_TAG_CLOUD_9:
2031         case IO_REPARSE_TAG_CLOUD_A:
2032         case IO_REPARSE_TAG_CLOUD_B:
2033         case IO_REPARSE_TAG_CLOUD_C:
2034         case IO_REPARSE_TAG_CLOUD_D:
2035         case IO_REPARSE_TAG_CLOUD_E:
2036         case IO_REPARSE_TAG_CLOUD_F:
2037                 err = sizeof("OneDrive") - 1;
2038                 if (err > buflen)
2039                         err = buflen;
2040                 memcpy(buffer, "OneDrive", err);
2041                 goto out;
2042
2043         default:
2044                 if (IsReparseTagMicrosoft(rp->ReparseTag)) {
2045                         /* Unknown Microsoft Tag. */
2046                         goto out;
2047                 }
2048                 if (!IsReparseTagNameSurrogate(rp->ReparseTag) ||
2049                     size <= sizeof(struct REPARSE_POINT)) {
2050                         goto out;
2051                 }
2052
2053                 /* Users tag. */
2054                 uname = Add2Ptr(rp, sizeof(struct REPARSE_POINT));
2055                 ulen = le16_to_cpu(rp->ReparseDataLength) -
2056                        sizeof(struct REPARSE_POINT);
2057         }
2058
2059         /* Convert nlen from bytes to UNICODE chars. */
2060         ulen >>= 1;
2061
2062         /* Check that name is available. */
2063         if (!ulen || uname + ulen > (__le16 *)Add2Ptr(rp, size))
2064                 goto out;
2065
2066         /* If name is already zero terminated then truncate it now. */
2067         if (!uname[ulen - 1])
2068                 ulen -= 1;
2069
2070         err = ntfs_utf16_to_nls(sbi, uname, ulen, buffer, buflen);
2071
2072         if (err < 0)
2073                 goto out;
2074
2075         /* Translate Windows '\' into Linux '/'. */
2076         for (i = 0; i < err; i++) {
2077                 if (buffer[i] == '\\')
2078                         buffer[i] = '/';
2079         }
2080
2081         /* Always set last zero. */
2082         buffer[err] = 0;
2083
2084         /* If this is a junction, translate the link target. */
2085         if (rp->ReparseTag == IO_REPARSE_TAG_MOUNT_POINT)
2086                 err = ntfs_translate_junction(sb, link_de, buffer, err, buflen);
2087
2088 out:
2089         kfree(to_free);
2090         return err;
2091 }
2092
2093 static const char *ntfs_get_link(struct dentry *de, struct inode *inode,
2094                                  struct delayed_call *done)
2095 {
2096         int err;
2097         char *ret;
2098
2099         if (!de)
2100                 return ERR_PTR(-ECHILD);
2101
2102         ret = kmalloc(PAGE_SIZE, GFP_NOFS);
2103         if (!ret)
2104                 return ERR_PTR(-ENOMEM);
2105
2106         err = ntfs_readlink_hlp(de, inode, ret, PAGE_SIZE);
2107         if (err < 0) {
2108                 kfree(ret);
2109                 return ERR_PTR(err);
2110         }
2111
2112         set_delayed_call(done, kfree_link, ret);
2113
2114         return ret;
2115 }
2116
2117 // clang-format off
2118 const struct inode_operations ntfs_link_inode_operations = {
2119         .get_link       = ntfs_get_link,
2120         .setattr        = ntfs3_setattr,
2121         .listxattr      = ntfs_listxattr,
2122 };
2123
2124 const struct address_space_operations ntfs_aops = {
2125         .read_folio     = ntfs_read_folio,
2126         .readahead      = ntfs_readahead,
2127         .writepages     = ntfs_writepages,
2128         .write_begin    = ntfs_write_begin,
2129         .write_end      = ntfs_write_end,
2130         .direct_IO      = ntfs_direct_IO,
2131         .bmap           = ntfs_bmap,
2132         .dirty_folio    = block_dirty_folio,
2133         .migrate_folio  = buffer_migrate_folio,
2134         .invalidate_folio = block_invalidate_folio,
2135 };
2136
2137 const struct address_space_operations ntfs_aops_cmpr = {
2138         .read_folio     = ntfs_read_folio,
2139         .readahead      = ntfs_readahead,
2140         .dirty_folio    = block_dirty_folio,
2141 };
2142 // clang-format on