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                 /*
 540                  * Sequence number is not expected.
 541                  * Looks like inode was reused but caller uses the old reference
 542                  */
 543                 iput(inode);
 544                 inode = ERR_PTR(-ESTALE);
 545         }
 546
 547         if (IS_ERR(inode))
 548                 ntfs_set_state(sb->s_fs_info, NTFS_DIRTY_ERROR);
 549
 550         return inode;
 551 }
 552
 553 enum get_block_ctx {
 554         GET_BLOCK_GENERAL = 0,
 555         GET_BLOCK_WRITE_BEGIN = 1,
 556         GET_BLOCK_DIRECT_IO_R = 2,
 557         GET_BLOCK_DIRECT_IO_W = 3,
 558         GET_BLOCK_BMAP = 4,
 559 };
 560
 561 static noinline int ntfs_get_block_vbo(struct inode *inode, u64 vbo,
 562                                        struct buffer_head *bh, int create,
 563                                        enum get_block_ctx ctx)
 564 {
 565         struct super_block *sb = inode->i_sb;
 566         struct ntfs_sb_info *sbi = sb->s_fs_info;
 567         struct ntfs_inode *ni = ntfs_i(inode);
 568         struct folio *folio = bh->b_folio;
 569         u8 cluster_bits = sbi->cluster_bits;
 570         u32 block_size = sb->s_blocksize;
 571         u64 bytes, lbo, valid;
 572         u32 off;
 573         int err;
 574         CLST vcn, lcn, len;
 575         bool new;
 576
 577         /* Clear previous state. */
 578         clear_buffer_new(bh);
 579         clear_buffer_uptodate(bh);
 580
 581         if (is_resident(ni)) {
 582                 bh->b_blocknr = RESIDENT_LCN;
 583                 bh->b_size = block_size;
 584                 if (!folio) {
 585                         /* direct io (read) or bmap call */
 586                         err = 0;
 587                 } else {
 588                         ni_lock(ni);
 589                         err = attr_data_read_resident(ni, folio);
 590                         ni_unlock(ni);
 591
 592                         if (!err)
 593                                 set_buffer_uptodate(bh);
 594                 }
 595                 return err;
 596         }
 597
 598         vcn = vbo >> cluster_bits;
 599         off = vbo & sbi->cluster_mask;
 600         new = false;
 601
 602         err = attr_data_get_block(ni, vcn, 1, &lcn, &len, create ? &new : NULL,
 603                                   create && sbi->cluster_size > PAGE_SIZE);
 604         if (err)
 605                 goto out;
 606
 607         if (!len)
 608                 return 0;
 609
 610         bytes = ((u64)len << cluster_bits) - off;
 611
 612         if (lcn >= sbi->used.bitmap.nbits) {
 613                 /* This case includes resident/compressed/sparse. */
 614                 if (!create) {
 615                         if (bh->b_size > bytes)
 616                                 bh->b_size = bytes;
 617                         return 0;
 618                 }
 619                 WARN_ON(1);
 620         }
 621
 622         if (new)
 623                 set_buffer_new(bh);
 624
 625         lbo = ((u64)lcn << cluster_bits) + off;
 626
 627         set_buffer_mapped(bh);
 628         bh->b_bdev = sb->s_bdev;
 629         bh->b_blocknr = lbo >> sb->s_blocksize_bits;
 630
 631         valid = ni->i_valid;
 632
 633         if (ctx == GET_BLOCK_DIRECT_IO_W) {
 634                 /* ntfs_direct_IO will update ni->i_valid. */
 635                 if (vbo >= valid)
 636                         set_buffer_new(bh);
 637         } else if (create) {
 638                 /* Normal write. */
 639                 if (bytes > bh->b_size)
 640                         bytes = bh->b_size;
 641
 642                 if (vbo >= valid)
 643                         set_buffer_new(bh);
 644
 645                 if (vbo + bytes > valid) {
 646                         ni->i_valid = vbo + bytes;
 647                         mark_inode_dirty(inode);
 648                 }
 649         } else if (vbo >= valid) {
 650                 /* Read out of valid data. */
 651                 clear_buffer_mapped(bh);
 652         } else if (vbo + bytes <= valid) {
 653                 /* Normal read. */
 654         } else if (vbo + block_size <= valid) {
 655                 /* Normal short read. */
 656                 bytes = block_size;
 657         } else {
 658                 /*
 659                  * Read across valid size: vbo < valid && valid < vbo + block_size
 660                  */
 661                 bytes = block_size;
 662
 663                 if (folio) {
 664                         u32 voff = valid - vbo;
 665
 666                         bh->b_size = block_size;
 667                         off = vbo & (PAGE_SIZE - 1);
 668                         folio_set_bh(bh, folio, off);
 669
 670                         if (bh_read(bh, 0) < 0) {
 671                                 err = -EIO;
 672                                 goto out;
 673                         }
 674                         folio_zero_segment(folio, off + voff, off + block_size);
 675                 }
 676         }
 677
 678         if (bh->b_size > bytes)
 679                 bh->b_size = bytes;
 680
 681 #ifndef __LP64__
 682         if (ctx == GET_BLOCK_DIRECT_IO_W || ctx == GET_BLOCK_DIRECT_IO_R) {
 683                 static_assert(sizeof(size_t) < sizeof(loff_t));
 684                 if (bytes > 0x40000000u)
 685                         bh->b_size = 0x40000000u;
 686         }
 687 #endif
 688
 689         return 0;
 690
 691 out:
 692         return err;
 693 }
 694
 695 int ntfs_get_block(struct inode *inode, sector_t vbn,
 696                    struct buffer_head *bh_result, int create)
 697 {
 698         return ntfs_get_block_vbo(inode, (u64)vbn << inode->i_blkbits,
 699                                   bh_result, create, GET_BLOCK_GENERAL);
 700 }
 701
 702 static int ntfs_get_block_bmap(struct inode *inode, sector_t vsn,
 703                                struct buffer_head *bh_result, int create)
 704 {
 705         return ntfs_get_block_vbo(inode,
 706                                   (u64)vsn << inode->i_sb->s_blocksize_bits,
 707                                   bh_result, create, GET_BLOCK_BMAP);
 708 }
 709
 710 static sector_t ntfs_bmap(struct address_space *mapping, sector_t block)
 711 {
 712         return generic_block_bmap(mapping, block, ntfs_get_block_bmap);
 713 }
 714
 715 static int ntfs_read_folio(struct file *file, struct folio *folio)
 716 {
 717         int err;
 718         struct address_space *mapping = folio->mapping;
 719         struct inode *inode = mapping->host;
 720         struct ntfs_inode *ni = ntfs_i(inode);
 721
 722         if (is_resident(ni)) {
 723                 ni_lock(ni);
 724                 err = attr_data_read_resident(ni, folio);
 725                 ni_unlock(ni);
 726                 if (err != E_NTFS_NONRESIDENT) {
 727                         folio_unlock(folio);
 728                         return err;
 729                 }
 730         }
 731
 732         if (is_compressed(ni)) {
 733                 ni_lock(ni);
 734                 err = ni_readpage_cmpr(ni, folio);
 735                 ni_unlock(ni);
 736                 return err;
 737         }
 738
 739         /* Normal + sparse files. */
 740         return mpage_read_folio(folio, ntfs_get_block);
 741 }
 742
 743 static void ntfs_readahead(struct readahead_control *rac)
 744 {
 745         struct address_space *mapping = rac->mapping;
 746         struct inode *inode = mapping->host;
 747         struct ntfs_inode *ni = ntfs_i(inode);
 748         u64 valid;
 749         loff_t pos;
 750
 751         if (is_resident(ni)) {
 752                 /* No readahead for resident. */
 753                 return;
 754         }
 755
 756         if (is_compressed(ni)) {
 757                 /* No readahead for compressed. */
 758                 return;
 759         }
 760
 761         valid = ni->i_valid;
 762         pos = readahead_pos(rac);
 763
 764         if (valid < i_size_read(inode) && pos <= valid &&
 765             valid < pos + readahead_length(rac)) {
 766                 /* Range cross 'valid'. Read it page by page. */
 767                 return;
 768         }
 769
 770         mpage_readahead(rac, ntfs_get_block);
 771 }
 772
 773 static int ntfs_get_block_direct_IO_R(struct inode *inode, sector_t iblock,
 774                                       struct buffer_head *bh_result, int create)
 775 {
 776         return ntfs_get_block_vbo(inode, (u64)iblock << inode->i_blkbits,
 777                                   bh_result, create, GET_BLOCK_DIRECT_IO_R);
 778 }
 779
 780 static int ntfs_get_block_direct_IO_W(struct inode *inode, sector_t iblock,
 781                                       struct buffer_head *bh_result, int create)
 782 {
 783         return ntfs_get_block_vbo(inode, (u64)iblock << inode->i_blkbits,
 784                                   bh_result, create, GET_BLOCK_DIRECT_IO_W);
 785 }
 786
 787 static ssize_t ntfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 788 {
 789         struct file *file = iocb->ki_filp;
 790         struct address_space *mapping = file->f_mapping;
 791         struct inode *inode = mapping->host;
 792         struct ntfs_inode *ni = ntfs_i(inode);
 793         loff_t vbo = iocb->ki_pos;
 794         loff_t end;
 795         int wr = iov_iter_rw(iter) & WRITE;
 796         size_t iter_count = iov_iter_count(iter);
 797         loff_t valid;
 798         ssize_t ret;
 799
 800         if (is_resident(ni)) {
 801                 /* Switch to buffered write. */
 802                 ret = 0;
 803                 goto out;
 804         }
 805
 806         ret = blockdev_direct_IO(iocb, inode, iter,
 807                                  wr ? ntfs_get_block_direct_IO_W :
 808                                       ntfs_get_block_direct_IO_R);
 809
 810         if (ret > 0)
 811                 end = vbo + ret;
 812         else if (wr && ret == -EIOCBQUEUED)
 813                 end = vbo + iter_count;
 814         else
 815                 goto out;
 816
 817         valid = ni->i_valid;
 818         if (wr) {
 819                 if (end > valid && !S_ISBLK(inode->i_mode)) {
 820                         ni->i_valid = end;
 821                         mark_inode_dirty(inode);
 822                 }
 823         } else if (vbo < valid && valid < end) {
 824                 /* Fix page. */
 825                 iov_iter_revert(iter, end - valid);
 826                 iov_iter_zero(end - valid, iter);
 827         }
 828
 829 out:
 830         return ret;
 831 }
 832
 833 int ntfs_set_size(struct inode *inode, u64 new_size)
 834 {
 835         struct super_block *sb = inode->i_sb;
 836         struct ntfs_sb_info *sbi = sb->s_fs_info;
 837         struct ntfs_inode *ni = ntfs_i(inode);
 838         int err;
 839
 840         /* Check for maximum file size. */
 841         if (is_sparsed(ni) || is_compressed(ni)) {
 842                 if (new_size > sbi->maxbytes_sparse) {
 843                         err = -EFBIG;
 844                         goto out;
 845                 }
 846         } else if (new_size > sbi->maxbytes) {
 847                 err = -EFBIG;
 848                 goto out;
 849         }
 850
 851         ni_lock(ni);
 852         down_write(&ni->file.run_lock);
 853
 854         err = attr_set_size(ni, ATTR_DATA, NULL, 0, &ni->file.run, new_size,
 855                             &ni->i_valid, true, NULL);
 856
 857         up_write(&ni->file.run_lock);
 858         ni_unlock(ni);
 859
 860         mark_inode_dirty(inode);
 861
 862 out:
 863         return err;
 864 }
 865
 866 static int ntfs_resident_writepage(struct folio *folio,
 867                                    struct writeback_control *wbc, void *data)
 868 {
 869         struct address_space *mapping = data;
 870         struct inode *inode = mapping->host;
 871         struct ntfs_inode *ni = ntfs_i(inode);
 872         int ret;
 873
 874         if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
 875                 return -EIO;
 876
 877         ni_lock(ni);
 878         ret = attr_data_write_resident(ni, folio);
 879         ni_unlock(ni);
 880
 881         if (ret != E_NTFS_NONRESIDENT)
 882                 folio_unlock(folio);
 883         mapping_set_error(mapping, ret);
 884         return ret;
 885 }
 886
 887 static int ntfs_writepages(struct address_space *mapping,
 888                            struct writeback_control *wbc)
 889 {
 890         struct inode *inode = mapping->host;
 891
 892         if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
 893                 return -EIO;
 894
 895         if (is_resident(ntfs_i(inode)))
 896                 return write_cache_pages(mapping, wbc, ntfs_resident_writepage,
 897                                          mapping);
 898         return mpage_writepages(mapping, wbc, ntfs_get_block);
 899 }
 900
 901 static int ntfs_get_block_write_begin(struct inode *inode, sector_t vbn,
 902                                       struct buffer_head *bh_result, int create)
 903 {
 904         return ntfs_get_block_vbo(inode, (u64)vbn << inode->i_blkbits,
 905                                   bh_result, create, GET_BLOCK_WRITE_BEGIN);
 906 }
 907
 908 int ntfs_write_begin(struct file *file, struct address_space *mapping,
 909                      loff_t pos, u32 len, struct folio **foliop, void **fsdata)
 910 {
 911         int err;
 912         struct inode *inode = mapping->host;
 913         struct ntfs_inode *ni = ntfs_i(inode);
 914
 915         if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
 916                 return -EIO;
 917
 918         if (is_resident(ni)) {
 919                 struct folio *folio = __filemap_get_folio(
 920                         mapping, pos >> PAGE_SHIFT, FGP_WRITEBEGIN,
 921                         mapping_gfp_mask(mapping));
 922
 923                 if (IS_ERR(folio)) {
 924                         err = PTR_ERR(folio);
 925                         goto out;
 926                 }
 927
 928                 ni_lock(ni);
 929                 err = attr_data_read_resident(ni, folio);
 930                 ni_unlock(ni);
 931
 932                 if (!err) {
 933                         *foliop = folio;
 934                         goto out;
 935                 }
 936                 folio_unlock(folio);
 937                 folio_put(folio);
 938
 939                 if (err != E_NTFS_NONRESIDENT)
 940                         goto out;
 941         }
 942
 943         err = block_write_begin(mapping, pos, len, foliop,
 944                                 ntfs_get_block_write_begin);
 945
 946 out:
 947         return err;
 948 }
 949
 950 /*
 951  * ntfs_write_end - Address_space_operations::write_end.
 952  */
 953 int ntfs_write_end(struct file *file, struct address_space *mapping, loff_t pos,
 954                    u32 len, u32 copied, struct folio *folio, void *fsdata)
 955 {
 956         struct inode *inode = mapping->host;
 957         struct ntfs_inode *ni = ntfs_i(inode);
 958         u64 valid = ni->i_valid;
 959         bool dirty = false;
 960         int err;
 961
 962         if (is_resident(ni)) {
 963                 ni_lock(ni);
 964                 err = attr_data_write_resident(ni, folio);
 965                 ni_unlock(ni);
 966                 if (!err) {
 967                         struct buffer_head *head = folio_buffers(folio);
 968                         dirty = true;
 969                         /* Clear any buffers in folio. */
 970                         if (head) {
 971                                 struct buffer_head *bh = head;
 972
 973                                 do {
 974                                         clear_buffer_dirty(bh);
 975                                         clear_buffer_mapped(bh);
 976                                         set_buffer_uptodate(bh);
 977                                 } while (head != (bh = bh->b_this_page));
 978                         }
 979                         folio_mark_uptodate(folio);
 980                         err = copied;
 981                 }
 982                 folio_unlock(folio);
 983                 folio_put(folio);
 984         } else {
 985                 err = generic_write_end(file, mapping, pos, len, copied, folio,
 986                                         fsdata);
 987         }
 988
 989         if (err >= 0) {
 990                 if (!(ni->std_fa & FILE_ATTRIBUTE_ARCHIVE)) {
 991                         inode_set_mtime_to_ts(inode,
 992                                               inode_set_ctime_current(inode));
 993                         ni->std_fa |= FILE_ATTRIBUTE_ARCHIVE;
 994                         dirty = true;
 995                 }
 996
 997                 if (valid != ni->i_valid) {
 998                         /* ni->i_valid is changed in ntfs_get_block_vbo. */
 999                         dirty = true;
1000                 }
1001
1002                 if (pos + err > inode->i_size) {
1003                         i_size_write(inode, pos + err);
1004                         dirty = true;
1005                 }
1006
1007                 if (dirty)
1008                         mark_inode_dirty(inode);
1009         }
1010
1011         return err;
1012 }
1013
1014 int ntfs3_write_inode(struct inode *inode, struct writeback_control *wbc)
1015 {
1016         return _ni_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
1017 }
1018
1019 int ntfs_sync_inode(struct inode *inode)
1020 {
1021         return _ni_write_inode(inode, 1);
1022 }
1023
1024 /*
1025  * writeback_inode - Helper function for ntfs_flush_inodes().
1026  *
1027  * This writes both the inode and the file data blocks, waiting
1028  * for in flight data blocks before the start of the call.  It
1029  * does not wait for any io started during the call.
1030  */
1031 static int writeback_inode(struct inode *inode)
1032 {
1033         int ret = sync_inode_metadata(inode, 0);
1034
1035         if (!ret)
1036                 ret = filemap_fdatawrite(inode->i_mapping);
1037         return ret;
1038 }
1039
1040 /*
1041  * ntfs_flush_inodes
1042  *
1043  * Write data and metadata corresponding to i1 and i2.  The io is
1044  * started but we do not wait for any of it to finish.
1045  *
1046  * filemap_flush() is used for the block device, so if there is a dirty
1047  * page for a block already in flight, we will not wait and start the
1048  * io over again.
1049  */
1050 int ntfs_flush_inodes(struct super_block *sb, struct inode *i1,
1051                       struct inode *i2)
1052 {
1053         int ret = 0;
1054
1055         if (i1)
1056                 ret = writeback_inode(i1);
1057         if (!ret && i2)
1058                 ret = writeback_inode(i2);
1059         if (!ret)
1060                 ret = filemap_flush(sb->s_bdev_file->f_mapping);
1061         return ret;
1062 }
1063
1064 /*
1065  * Helper function to read file.
1066  */
1067 int inode_read_data(struct inode *inode, void *data, size_t bytes)
1068 {
1069         pgoff_t idx;
1070         struct address_space *mapping = inode->i_mapping;
1071
1072         for (idx = 0; bytes; idx++) {
1073                 size_t op = bytes > PAGE_SIZE ? PAGE_SIZE : bytes;
1074                 struct page *page = read_mapping_page(mapping, idx, NULL);
1075                 void *kaddr;
1076
1077                 if (IS_ERR(page))
1078                         return PTR_ERR(page);
1079
1080                 kaddr = kmap_atomic(page);
1081                 memcpy(data, kaddr, op);
1082                 kunmap_atomic(kaddr);
1083
1084                 put_page(page);
1085
1086                 bytes -= op;
1087                 data = Add2Ptr(data, PAGE_SIZE);
1088         }
1089         return 0;
1090 }
1091
1092 /*
1093  * ntfs_reparse_bytes
1094  *
1095  * Number of bytes for REPARSE_DATA_BUFFER(IO_REPARSE_TAG_SYMLINK)
1096  * for unicode string of @uni_len length.
1097  */
1098 static inline u32 ntfs_reparse_bytes(u32 uni_len)
1099 {
1100         /* Header + unicode string + decorated unicode string. */
1101         return sizeof(short) * (2 * uni_len + 4) +
1102                offsetof(struct REPARSE_DATA_BUFFER,
1103                         SymbolicLinkReparseBuffer.PathBuffer);
1104 }
1105
1106 static struct REPARSE_DATA_BUFFER *
1107 ntfs_create_reparse_buffer(struct ntfs_sb_info *sbi, const char *symname,
1108                            u32 size, u16 *nsize)
1109 {
1110         int i, err;
1111         struct REPARSE_DATA_BUFFER *rp;
1112         __le16 *rp_name;
1113         typeof(rp->SymbolicLinkReparseBuffer) *rs;
1114
1115         rp = kzalloc(ntfs_reparse_bytes(2 * size + 2), GFP_NOFS);
1116         if (!rp)
1117                 return ERR_PTR(-ENOMEM);
1118
1119         rs = &rp->SymbolicLinkReparseBuffer;
1120         rp_name = rs->PathBuffer;
1121
1122         /* Convert link name to UTF-16. */
1123         err = ntfs_nls_to_utf16(sbi, symname, size,
1124                                 (struct cpu_str *)(rp_name - 1), 2 * size,
1125                                 UTF16_LITTLE_ENDIAN);
1126         if (err < 0)
1127                 goto out;
1128
1129         /* err = the length of unicode name of symlink. */
1130         *nsize = ntfs_reparse_bytes(err);
1131
1132         if (*nsize > sbi->reparse.max_size) {
1133                 err = -EFBIG;
1134                 goto out;
1135         }
1136
1137         /* Translate Linux '/' into Windows '\'. */
1138         for (i = 0; i < err; i++) {
1139                 if (rp_name[i] == cpu_to_le16('/'))
1140                         rp_name[i] = cpu_to_le16('\\');
1141         }
1142
1143         rp->ReparseTag = IO_REPARSE_TAG_SYMLINK;
1144         rp->ReparseDataLength =
1145                 cpu_to_le16(*nsize - offsetof(struct REPARSE_DATA_BUFFER,
1146                                               SymbolicLinkReparseBuffer));
1147
1148         /* PrintName + SubstituteName. */
1149         rs->SubstituteNameOffset = cpu_to_le16(sizeof(short) * err);
1150         rs->SubstituteNameLength = cpu_to_le16(sizeof(short) * err + 8);
1151         rs->PrintNameLength = rs->SubstituteNameOffset;
1152
1153         /*
1154          * TODO: Use relative path if possible to allow Windows to
1155          * parse this path.
1156          * 0-absolute path 1- relative path (SYMLINK_FLAG_RELATIVE).
1157          */
1158         rs->Flags = 0;
1159
1160         memmove(rp_name + err + 4, rp_name, sizeof(short) * err);
1161
1162         /* Decorate SubstituteName. */
1163         rp_name += err;
1164         rp_name[0] = cpu_to_le16('\\');
1165         rp_name[1] = cpu_to_le16('?');
1166         rp_name[2] = cpu_to_le16('?');
1167         rp_name[3] = cpu_to_le16('\\');
1168
1169         return rp;
1170 out:
1171         kfree(rp);
1172         return ERR_PTR(err);
1173 }
1174
1175 /*
1176  * ntfs_create_inode
1177  *
1178  * Helper function for:
1179  * - ntfs_create
1180  * - ntfs_mknod
1181  * - ntfs_symlink
1182  * - ntfs_mkdir
1183  * - ntfs_atomic_open
1184  *
1185  * NOTE: if fnd != NULL (ntfs_atomic_open) then @dir is locked
1186  */
1187 int ntfs_create_inode(struct mnt_idmap *idmap, struct inode *dir,
1188                       struct dentry *dentry, const struct cpu_str *uni,
1189                       umode_t mode, dev_t dev, const char *symname, u32 size,
1190                       struct ntfs_fnd *fnd)
1191 {
1192         int err;
1193         struct super_block *sb = dir->i_sb;
1194         struct ntfs_sb_info *sbi = sb->s_fs_info;
1195         const struct qstr *name = &dentry->d_name;
1196         CLST ino = 0;
1197         struct ntfs_inode *dir_ni = ntfs_i(dir);
1198         struct ntfs_inode *ni = NULL;
1199         struct inode *inode = NULL;
1200         struct ATTRIB *attr;
1201         struct ATTR_STD_INFO5 *std5;
1202         struct ATTR_FILE_NAME *fname;
1203         struct MFT_REC *rec;
1204         u32 asize, dsize, sd_size;
1205         enum FILE_ATTRIBUTE fa;
1206         __le32 security_id = SECURITY_ID_INVALID;
1207         CLST vcn;
1208         const void *sd;
1209         u16 t16, nsize = 0, aid = 0;
1210         struct INDEX_ROOT *root, *dir_root;
1211         struct NTFS_DE *e, *new_de = NULL;
1212         struct REPARSE_DATA_BUFFER *rp = NULL;
1213         bool rp_inserted = false;
1214
1215         /* New file will be resident or non resident. */
1216         const bool new_file_resident = 1;
1217
1218         if (!fnd)
1219                 ni_lock_dir(dir_ni);
1220
1221         dir_root = indx_get_root(&dir_ni->dir, dir_ni, NULL, NULL);
1222         if (!dir_root) {
1223                 err = -EINVAL;
1224                 goto out1;
1225         }
1226
1227         if (S_ISDIR(mode)) {
1228                 /* Use parent's directory attributes. */
1229                 fa = dir_ni->std_fa | FILE_ATTRIBUTE_DIRECTORY |
1230                      FILE_ATTRIBUTE_ARCHIVE;
1231                 /*
1232                  * By default child directory inherits parent attributes.
1233                  * Root directory is hidden + system.
1234                  * Make an exception for children in root.
1235                  */
1236                 if (dir->i_ino == MFT_REC_ROOT)
1237                         fa &= ~(FILE_ATTRIBUTE_HIDDEN | FILE_ATTRIBUTE_SYSTEM);
1238         } else if (S_ISLNK(mode)) {
1239                 /* It is good idea that link should be the same type (file/dir) as target */
1240                 fa = FILE_ATTRIBUTE_REPARSE_POINT;
1241
1242                 /*
1243                  * Linux: there are dir/file/symlink and so on.
1244                  * NTFS: symlinks are "dir + reparse" or "file + reparse"
1245                  * It is good idea to create:
1246                  * dir + reparse if 'symname' points to directory
1247                  * or
1248                  * file + reparse if 'symname' points to file
1249                  * Unfortunately kern_path hangs if symname contains 'dir'.
1250                  */
1251
1252                 /*
1253                  *      struct path path;
1254                  *
1255                  *      if (!kern_path(symname, LOOKUP_FOLLOW, &path)){
1256                  *              struct inode *target = d_inode(path.dentry);
1257                  *
1258                  *              if (S_ISDIR(target->i_mode))
1259                  *                      fa |= FILE_ATTRIBUTE_DIRECTORY;
1260                  *              // if ( target->i_sb == sb ){
1261                  *              //      use relative path?
1262                  *              // }
1263                  *              path_put(&path);
1264                  *      }
1265                  */
1266         } else if (S_ISREG(mode)) {
1267                 if (sbi->options->sparse) {
1268                         /* Sparsed regular file, cause option 'sparse'. */
1269                         fa = FILE_ATTRIBUTE_SPARSE_FILE |
1270                              FILE_ATTRIBUTE_ARCHIVE;
1271                 } else if (dir_ni->std_fa & FILE_ATTRIBUTE_COMPRESSED) {
1272                         /* Compressed regular file, if parent is compressed. */
1273                         fa = FILE_ATTRIBUTE_COMPRESSED | FILE_ATTRIBUTE_ARCHIVE;
1274                 } else {
1275                         /* Regular file, default attributes. */
1276                         fa = FILE_ATTRIBUTE_ARCHIVE;
1277                 }
1278         } else {
1279                 fa = FILE_ATTRIBUTE_ARCHIVE;
1280         }
1281
1282         /* If option "hide_dot_files" then set hidden attribute for dot files. */
1283         if (sbi->options->hide_dot_files && name->name[0] == '.')
1284                 fa |= FILE_ATTRIBUTE_HIDDEN;
1285
1286         if (!(mode & 0222))
1287                 fa |= FILE_ATTRIBUTE_READONLY;
1288
1289         /* Allocate PATH_MAX bytes. */
1290         new_de = __getname();
1291         if (!new_de) {
1292                 err = -ENOMEM;
1293                 goto out1;
1294         }
1295
1296         if (unlikely(ntfs3_forced_shutdown(sb))) {
1297                 err = -EIO;
1298                 goto out2;
1299         }
1300
1301         /* Mark rw ntfs as dirty. it will be cleared at umount. */
1302         ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
1303
1304         /* Step 1: allocate and fill new mft record. */
1305         err = ntfs_look_free_mft(sbi, &ino, false, NULL, NULL);
1306         if (err)
1307                 goto out2;
1308
1309         ni = ntfs_new_inode(sbi, ino, S_ISDIR(mode) ? RECORD_FLAG_DIR : 0);
1310         if (IS_ERR(ni)) {
1311                 err = PTR_ERR(ni);
1312                 ni = NULL;
1313                 goto out3;
1314         }
1315         inode = &ni->vfs_inode;
1316         inode_init_owner(idmap, inode, dir, mode);
1317         mode = inode->i_mode;
1318
1319         ni->i_crtime = current_time(inode);
1320
1321         rec = ni->mi.mrec;
1322         rec->hard_links = cpu_to_le16(1);
1323         attr = Add2Ptr(rec, le16_to_cpu(rec->attr_off));
1324
1325         /* Get default security id. */
1326         sd = s_default_security;
1327         sd_size = sizeof(s_default_security);
1328
1329         if (is_ntfs3(sbi)) {
1330                 security_id = dir_ni->std_security_id;
1331                 if (le32_to_cpu(security_id) < SECURITY_ID_FIRST) {
1332                         security_id = sbi->security.def_security_id;
1333
1334                         if (security_id == SECURITY_ID_INVALID &&
1335                             !ntfs_insert_security(sbi, sd, sd_size,
1336                                                   &security_id, NULL))
1337                                 sbi->security.def_security_id = security_id;
1338                 }
1339         }
1340
1341         /* Insert standard info. */
1342         std5 = Add2Ptr(attr, SIZEOF_RESIDENT);
1343
1344         if (security_id == SECURITY_ID_INVALID) {
1345                 dsize = sizeof(struct ATTR_STD_INFO);
1346         } else {
1347                 dsize = sizeof(struct ATTR_STD_INFO5);
1348                 std5->security_id = security_id;
1349                 ni->std_security_id = security_id;
1350         }
1351         asize = SIZEOF_RESIDENT + dsize;
1352
1353         attr->type = ATTR_STD;
1354         attr->size = cpu_to_le32(asize);
1355         attr->id = cpu_to_le16(aid++);
1356         attr->res.data_off = SIZEOF_RESIDENT_LE;
1357         attr->res.data_size = cpu_to_le32(dsize);
1358
1359         std5->cr_time = std5->m_time = std5->c_time = std5->a_time =
1360                 kernel2nt(&ni->i_crtime);
1361
1362         std5->fa = ni->std_fa = fa;
1363
1364         attr = Add2Ptr(attr, asize);
1365
1366         /* Insert file name. */
1367         err = fill_name_de(sbi, new_de, name, uni);
1368         if (err)
1369                 goto out4;
1370
1371         mi_get_ref(&ni->mi, &new_de->ref);
1372
1373         fname = (struct ATTR_FILE_NAME *)(new_de + 1);
1374
1375         if (sbi->options->windows_names &&
1376             !valid_windows_name(sbi, (struct le_str *)&fname->name_len)) {
1377                 err = -EINVAL;
1378                 goto out4;
1379         }
1380
1381         mi_get_ref(&dir_ni->mi, &fname->home);
1382         fname->dup.cr_time = fname->dup.m_time = fname->dup.c_time =
1383                 fname->dup.a_time = std5->cr_time;
1384         fname->dup.alloc_size = fname->dup.data_size = 0;
1385         fname->dup.fa = std5->fa;
1386         fname->dup.ea_size = fname->dup.reparse = 0;
1387
1388         dsize = le16_to_cpu(new_de->key_size);
1389         asize = ALIGN(SIZEOF_RESIDENT + dsize, 8);
1390
1391         attr->type = ATTR_NAME;
1392         attr->size = cpu_to_le32(asize);
1393         attr->res.data_off = SIZEOF_RESIDENT_LE;
1394         attr->res.flags = RESIDENT_FLAG_INDEXED;
1395         attr->id = cpu_to_le16(aid++);
1396         attr->res.data_size = cpu_to_le32(dsize);
1397         memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), fname, dsize);
1398
1399         attr = Add2Ptr(attr, asize);
1400
1401         if (security_id == SECURITY_ID_INVALID) {
1402                 /* Insert security attribute. */
1403                 asize = SIZEOF_RESIDENT + ALIGN(sd_size, 8);
1404
1405                 attr->type = ATTR_SECURE;
1406                 attr->size = cpu_to_le32(asize);
1407                 attr->id = cpu_to_le16(aid++);
1408                 attr->res.data_off = SIZEOF_RESIDENT_LE;
1409                 attr->res.data_size = cpu_to_le32(sd_size);
1410                 memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), sd, sd_size);
1411
1412                 attr = Add2Ptr(attr, asize);
1413         }
1414
1415         attr->id = cpu_to_le16(aid++);
1416         if (fa & FILE_ATTRIBUTE_DIRECTORY) {
1417                 /*
1418                  * Regular directory or symlink to directory.
1419                  * Create root attribute.
1420                  */
1421                 dsize = sizeof(struct INDEX_ROOT) + sizeof(struct NTFS_DE);
1422                 asize = sizeof(I30_NAME) + SIZEOF_RESIDENT + dsize;
1423
1424                 attr->type = ATTR_ROOT;
1425                 attr->size = cpu_to_le32(asize);
1426
1427                 attr->name_len = ARRAY_SIZE(I30_NAME);
1428                 attr->name_off = SIZEOF_RESIDENT_LE;
1429                 attr->res.data_off =
1430                         cpu_to_le16(sizeof(I30_NAME) + SIZEOF_RESIDENT);
1431                 attr->res.data_size = cpu_to_le32(dsize);
1432                 memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), I30_NAME,
1433                        sizeof(I30_NAME));
1434
1435                 root = Add2Ptr(attr, sizeof(I30_NAME) + SIZEOF_RESIDENT);
1436                 memcpy(root, dir_root, offsetof(struct INDEX_ROOT, ihdr));
1437                 root->ihdr.de_off = cpu_to_le32(sizeof(struct INDEX_HDR));
1438                 root->ihdr.used = cpu_to_le32(sizeof(struct INDEX_HDR) +
1439                                               sizeof(struct NTFS_DE));
1440                 root->ihdr.total = root->ihdr.used;
1441
1442                 e = Add2Ptr(root, sizeof(struct INDEX_ROOT));
1443                 e->size = cpu_to_le16(sizeof(struct NTFS_DE));
1444                 e->flags = NTFS_IE_LAST;
1445         } else if (S_ISLNK(mode)) {
1446                 /*
1447                  * Symlink to file.
1448                  * Create empty resident data attribute.
1449                  */
1450                 asize = SIZEOF_RESIDENT;
1451
1452                 /* Insert empty ATTR_DATA */
1453                 attr->type = ATTR_DATA;
1454                 attr->size = cpu_to_le32(SIZEOF_RESIDENT);
1455                 attr->name_off = SIZEOF_RESIDENT_LE;
1456                 attr->res.data_off = SIZEOF_RESIDENT_LE;
1457         } else if (!new_file_resident && S_ISREG(mode)) {
1458                 /*
1459                  * Regular file. Create empty non resident data attribute.
1460                  */
1461                 attr->type = ATTR_DATA;
1462                 attr->non_res = 1;
1463                 attr->nres.evcn = cpu_to_le64(-1ll);
1464                 if (fa & FILE_ATTRIBUTE_SPARSE_FILE) {
1465                         attr->size = cpu_to_le32(SIZEOF_NONRESIDENT_EX + 8);
1466                         attr->name_off = SIZEOF_NONRESIDENT_EX_LE;
1467                         attr->flags = ATTR_FLAG_SPARSED;
1468                         asize = SIZEOF_NONRESIDENT_EX + 8;
1469                 } else if (fa & FILE_ATTRIBUTE_COMPRESSED) {
1470                         attr->size = cpu_to_le32(SIZEOF_NONRESIDENT_EX + 8);
1471                         attr->name_off = SIZEOF_NONRESIDENT_EX_LE;
1472                         attr->flags = ATTR_FLAG_COMPRESSED;
1473                         attr->nres.c_unit = NTFS_LZNT_CUNIT;
1474                         asize = SIZEOF_NONRESIDENT_EX + 8;
1475                 } else {
1476                         attr->size = cpu_to_le32(SIZEOF_NONRESIDENT + 8);
1477                         attr->name_off = SIZEOF_NONRESIDENT_LE;
1478                         asize = SIZEOF_NONRESIDENT + 8;
1479                 }
1480                 attr->nres.run_off = attr->name_off;
1481         } else {
1482                 /*
1483                  * Node. Create empty resident data attribute.
1484                  */
1485                 attr->type = ATTR_DATA;
1486                 attr->size = cpu_to_le32(SIZEOF_RESIDENT);
1487                 attr->name_off = SIZEOF_RESIDENT_LE;
1488                 if (fa & FILE_ATTRIBUTE_SPARSE_FILE)
1489                         attr->flags = ATTR_FLAG_SPARSED;
1490                 else if (fa & FILE_ATTRIBUTE_COMPRESSED)
1491                         attr->flags = ATTR_FLAG_COMPRESSED;
1492                 attr->res.data_off = SIZEOF_RESIDENT_LE;
1493                 asize = SIZEOF_RESIDENT;
1494                 ni->ni_flags |= NI_FLAG_RESIDENT;
1495         }
1496
1497         if (S_ISDIR(mode)) {
1498                 ni->ni_flags |= NI_FLAG_DIR;
1499                 err = indx_init(&ni->dir, sbi, attr, INDEX_MUTEX_I30);
1500                 if (err)
1501                         goto out4;
1502         } else if (S_ISLNK(mode)) {
1503                 rp = ntfs_create_reparse_buffer(sbi, symname, size, &nsize);
1504
1505                 if (IS_ERR(rp)) {
1506                         err = PTR_ERR(rp);
1507                         rp = NULL;
1508                         goto out4;
1509                 }
1510
1511                 /*
1512                  * Insert ATTR_REPARSE.
1513                  */
1514                 attr = Add2Ptr(attr, asize);
1515                 attr->type = ATTR_REPARSE;
1516                 attr->id = cpu_to_le16(aid++);
1517
1518                 /* Resident or non resident? */
1519                 asize = ALIGN(SIZEOF_RESIDENT + nsize, 8);
1520                 t16 = PtrOffset(rec, attr);
1521
1522                 /*
1523                  * Below function 'ntfs_save_wsl_perm' requires 0x78 bytes.
1524                  * It is good idea to keep extended attributes resident.
1525                  */
1526                 if (asize + t16 + 0x78 + 8 > sbi->record_size) {
1527                         CLST alen;
1528                         CLST clst = bytes_to_cluster(sbi, nsize);
1529
1530                         /* Bytes per runs. */
1531                         t16 = sbi->record_size - t16 - SIZEOF_NONRESIDENT;
1532
1533                         attr->non_res = 1;
1534                         attr->nres.evcn = cpu_to_le64(clst - 1);
1535                         attr->name_off = SIZEOF_NONRESIDENT_LE;
1536                         attr->nres.run_off = attr->name_off;
1537                         attr->nres.data_size = cpu_to_le64(nsize);
1538                         attr->nres.valid_size = attr->nres.data_size;
1539                         attr->nres.alloc_size =
1540                                 cpu_to_le64(ntfs_up_cluster(sbi, nsize));
1541
1542                         err = attr_allocate_clusters(sbi, &ni->file.run, 0, 0,
1543                                                      clst, NULL, ALLOCATE_DEF,
1544                                                      &alen, 0, NULL, NULL);
1545                         if (err)
1546                                 goto out5;
1547
1548                         err = run_pack(&ni->file.run, 0, clst,
1549                                        Add2Ptr(attr, SIZEOF_NONRESIDENT), t16,
1550                                        &vcn);
1551                         if (err < 0)
1552                                 goto out5;
1553
1554                         if (vcn != clst) {
1555                                 err = -EINVAL;
1556                                 goto out5;
1557                         }
1558
1559                         asize = SIZEOF_NONRESIDENT + ALIGN(err, 8);
1560                         /* Write non resident data. */
1561                         err = ntfs_sb_write_run(sbi, &ni->file.run, 0, rp,
1562                                                 nsize, 0);
1563                         if (err)
1564                                 goto out5;
1565                 } else {
1566                         attr->res.data_off = SIZEOF_RESIDENT_LE;
1567                         attr->res.data_size = cpu_to_le32(nsize);
1568                         memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), rp, nsize);
1569                 }
1570                 /* Size of symlink equals the length of input string. */
1571                 inode->i_size = size;
1572
1573                 attr->size = cpu_to_le32(asize);
1574
1575                 err = ntfs_insert_reparse(sbi, IO_REPARSE_TAG_SYMLINK,
1576                                           &new_de->ref);
1577                 if (err)
1578                         goto out5;
1579
1580                 rp_inserted = true;
1581         }
1582
1583         attr = Add2Ptr(attr, asize);
1584         attr->type = ATTR_END;
1585
1586         rec->used = cpu_to_le32(PtrOffset(rec, attr) + 8);
1587         rec->next_attr_id = cpu_to_le16(aid);
1588
1589         inode->i_generation = le16_to_cpu(rec->seq);
1590
1591         if (S_ISDIR(mode)) {
1592                 inode->i_op = &ntfs_dir_inode_operations;
1593                 inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
1594                                        &ntfs_legacy_dir_operations :
1595                                        &ntfs_dir_operations;
1596         } else if (S_ISLNK(mode)) {
1597                 inode->i_op = &ntfs_link_inode_operations;
1598                 inode->i_fop = NULL;
1599                 inode->i_mapping->a_ops = &ntfs_aops;
1600                 inode->i_size = size;
1601                 inode_nohighmem(inode);
1602         } else if (S_ISREG(mode)) {
1603                 inode->i_op = &ntfs_file_inode_operations;
1604                 inode->i_fop = unlikely(is_legacy_ntfs(sb)) ?
1605                                        &ntfs_legacy_file_operations :
1606                                        &ntfs_file_operations;
1607                 inode->i_mapping->a_ops = is_compressed(ni) ? &ntfs_aops_cmpr :
1608                                                               &ntfs_aops;
1609                 init_rwsem(&ni->file.run_lock);
1610         } else {
1611                 inode->i_op = &ntfs_special_inode_operations;
1612                 init_special_inode(inode, mode, dev);
1613         }
1614
1615 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
1616         if (!S_ISLNK(mode) && (sb->s_flags & SB_POSIXACL)) {
1617                 err = ntfs_init_acl(idmap, inode, dir);
1618                 if (err)
1619                         goto out5;
1620         } else
1621 #endif
1622         {
1623                 inode->i_flags |= S_NOSEC;
1624         }
1625
1626         /*
1627          * ntfs_init_acl and ntfs_save_wsl_perm update extended attribute.
1628          * The packed size of extended attribute is stored in direntry too.
1629          * 'fname' here points to inside new_de.
1630          */
1631         err = ntfs_save_wsl_perm(inode, &fname->dup.ea_size);
1632         if (err)
1633                 goto out6;
1634
1635         /*
1636          * update ea_size in file_name attribute too.
1637          * Use ni_find_attr cause layout of MFT record may be changed
1638          * in ntfs_init_acl and ntfs_save_wsl_perm.
1639          */
1640         attr = ni_find_attr(ni, NULL, NULL, ATTR_NAME, NULL, 0, NULL, NULL);
1641         if (attr) {
1642                 struct ATTR_FILE_NAME *fn;
1643
1644                 fn = resident_data_ex(attr, SIZEOF_ATTRIBUTE_FILENAME);
1645                 if (fn)
1646                         fn->dup.ea_size = fname->dup.ea_size;
1647         }
1648
1649         /* We do not need to update parent directory later */
1650         ni->ni_flags &= ~NI_FLAG_UPDATE_PARENT;
1651
1652         /* Step 2: Add new name in index. */
1653         err = indx_insert_entry(&dir_ni->dir, dir_ni, new_de, sbi, fnd, 0);
1654         if (err)
1655                 goto out6;
1656
1657         /*
1658          * Call 'd_instantiate' after inode->i_op is set
1659          * but before finish_open.
1660          */
1661         d_instantiate(dentry, inode);
1662
1663         /* Set original time. inode times (i_ctime) may be changed in ntfs_init_acl. */
1664         inode_set_atime_to_ts(inode, ni->i_crtime);
1665         inode_set_ctime_to_ts(inode, ni->i_crtime);
1666         inode_set_mtime_to_ts(inode, ni->i_crtime);
1667         inode_set_mtime_to_ts(dir, ni->i_crtime);
1668         inode_set_ctime_to_ts(dir, ni->i_crtime);
1669
1670         mark_inode_dirty(dir);
1671         mark_inode_dirty(inode);
1672
1673         /* Normal exit. */
1674         goto out2;
1675
1676 out6:
1677         attr = ni_find_attr(ni, NULL, NULL, ATTR_EA, NULL, 0, NULL, NULL);
1678         if (attr && attr->non_res) {
1679                 /* Delete ATTR_EA, if non-resident. */
1680                 struct runs_tree run;
1681                 run_init(&run);
1682                 attr_set_size(ni, ATTR_EA, NULL, 0, &run, 0, NULL, false, NULL);
1683                 run_close(&run);
1684         }
1685
1686         if (rp_inserted)
1687                 ntfs_remove_reparse(sbi, IO_REPARSE_TAG_SYMLINK, &new_de->ref);
1688
1689 out5:
1690         if (!S_ISDIR(mode))
1691                 run_deallocate(sbi, &ni->file.run, false);
1692
1693 out4:
1694         clear_rec_inuse(rec);
1695         clear_nlink(inode);
1696         ni->mi.dirty = false;
1697         discard_new_inode(inode);
1698 out3:
1699         ntfs_mark_rec_free(sbi, ino, false);
1700
1701 out2:
1702         __putname(new_de);
1703         kfree(rp);
1704
1705 out1:
1706         if (!fnd)
1707                 ni_unlock(dir_ni);
1708
1709         if (!err)
1710                 unlock_new_inode(inode);
1711
1712         return err;
1713 }
1714
1715 int ntfs_link_inode(struct inode *inode, struct dentry *dentry)
1716 {
1717         int err;
1718         struct ntfs_inode *ni = ntfs_i(inode);
1719         struct ntfs_sb_info *sbi = inode->i_sb->s_fs_info;
1720         struct NTFS_DE *de;
1721
1722         /* Allocate PATH_MAX bytes. */
1723         de = __getname();
1724         if (!de)
1725                 return -ENOMEM;
1726
1727         /* Mark rw ntfs as dirty. It will be cleared at umount. */
1728         ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
1729
1730         /* Construct 'de'. */
1731         err = fill_name_de(sbi, de, &dentry->d_name, NULL);
1732         if (err)
1733                 goto out;
1734
1735         err = ni_add_name(ntfs_i(d_inode(dentry->d_parent)), ni, de);
1736 out:
1737         __putname(de);
1738         return err;
1739 }
1740
1741 /*
1742  * ntfs_unlink_inode
1743  *
1744  * inode_operations::unlink
1745  * inode_operations::rmdir
1746  */
1747 int ntfs_unlink_inode(struct inode *dir, const struct dentry *dentry)
1748 {
1749         int err;
1750         struct ntfs_sb_info *sbi = dir->i_sb->s_fs_info;
1751         struct inode *inode = d_inode(dentry);
1752         struct ntfs_inode *ni = ntfs_i(inode);
1753         struct ntfs_inode *dir_ni = ntfs_i(dir);
1754         struct NTFS_DE *de, *de2 = NULL;
1755         int undo_remove;
1756
1757         if (ntfs_is_meta_file(sbi, ni->mi.rno))
1758                 return -EINVAL;
1759
1760         /* Allocate PATH_MAX bytes. */
1761         de = __getname();
1762         if (!de)
1763                 return -ENOMEM;
1764
1765         ni_lock(ni);
1766
1767         if (S_ISDIR(inode->i_mode) && !dir_is_empty(inode)) {
1768                 err = -ENOTEMPTY;
1769                 goto out;
1770         }
1771
1772         err = fill_name_de(sbi, de, &dentry->d_name, NULL);
1773         if (err < 0)
1774                 goto out;
1775
1776         undo_remove = 0;
1777         err = ni_remove_name(dir_ni, ni, de, &de2, &undo_remove);
1778
1779         if (!err) {
1780                 drop_nlink(inode);
1781                 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
1782                 mark_inode_dirty(dir);
1783                 inode_set_ctime_to_ts(inode, inode_get_ctime(dir));
1784                 if (inode->i_nlink)
1785                         mark_inode_dirty(inode);
1786         } else if (!ni_remove_name_undo(dir_ni, ni, de, de2, undo_remove)) {
1787                 _ntfs_bad_inode(inode);
1788         } else {
1789                 if (ni_is_dirty(dir))
1790                         mark_inode_dirty(dir);
1791                 if (ni_is_dirty(inode))
1792                         mark_inode_dirty(inode);
1793         }
1794
1795 out:
1796         ni_unlock(ni);
1797         __putname(de);
1798         return err;
1799 }
1800
1801 void ntfs_evict_inode(struct inode *inode)
1802 {
1803         truncate_inode_pages_final(&inode->i_data);
1804
1805         invalidate_inode_buffers(inode);
1806         clear_inode(inode);
1807
1808         ni_clear(ntfs_i(inode));
1809 }
1810
1811 /*
1812  * ntfs_translate_junction
1813  *
1814  * Translate a Windows junction target to the Linux equivalent.
1815  * On junctions, targets are always absolute (they include the drive
1816  * letter). We have no way of knowing if the target is for the current
1817  * mounted device or not so we just assume it is.
1818  */
1819 static int ntfs_translate_junction(const struct super_block *sb,
1820                                    const struct dentry *link_de, char *target,
1821                                    int target_len, int target_max)
1822 {
1823         int tl_len, err = target_len;
1824         char *link_path_buffer = NULL, *link_path;
1825         char *translated = NULL;
1826         char *target_start;
1827         int copy_len;
1828
1829         link_path_buffer = kmalloc(PATH_MAX, GFP_NOFS);
1830         if (!link_path_buffer) {
1831                 err = -ENOMEM;
1832                 goto out;
1833         }
1834         /* Get link path, relative to mount point */
1835         link_path = dentry_path_raw(link_de, link_path_buffer, PATH_MAX);
1836         if (IS_ERR(link_path)) {
1837                 ntfs_err(sb, "Error getting link path");
1838                 err = -EINVAL;
1839                 goto out;
1840         }
1841
1842         translated = kmalloc(PATH_MAX, GFP_NOFS);
1843         if (!translated) {
1844                 err = -ENOMEM;
1845                 goto out;
1846         }
1847
1848         /* Make translated path a relative path to mount point */
1849         strcpy(translated, "./");
1850         ++link_path; /* Skip leading / */
1851         for (tl_len = sizeof("./") - 1; *link_path; ++link_path) {
1852                 if (*link_path == '/') {
1853                         if (PATH_MAX - tl_len < sizeof("../")) {
1854                                 ntfs_err(sb,
1855                                          "Link path %s has too many components",
1856                                          link_path);
1857                                 err = -EINVAL;
1858                                 goto out;
1859                         }
1860                         strcpy(translated + tl_len, "../");
1861                         tl_len += sizeof("../") - 1;
1862                 }
1863         }
1864
1865         /* Skip drive letter */
1866         target_start = target;
1867         while (*target_start && *target_start != ':')
1868                 ++target_start;
1869
1870         if (!*target_start) {
1871                 ntfs_err(sb, "Link target (%s) missing drive separator",
1872                          target);
1873                 err = -EINVAL;
1874                 goto out;
1875         }
1876
1877         /* Skip drive separator and leading /, if exists */
1878         target_start += 1 + (target_start[1] == '/');
1879         copy_len = target_len - (target_start - target);
1880
1881         if (PATH_MAX - tl_len <= copy_len) {
1882                 ntfs_err(sb, "Link target %s too large for buffer (%d <= %d)",
1883                          target_start, PATH_MAX - tl_len, copy_len);
1884                 err = -EINVAL;
1885                 goto out;
1886         }
1887
1888         /* translated path has a trailing / and target_start does not */
1889         strcpy(translated + tl_len, target_start);
1890         tl_len += copy_len;
1891         if (target_max <= tl_len) {
1892                 ntfs_err(sb, "Target path %s too large for buffer (%d <= %d)",
1893                          translated, target_max, tl_len);
1894                 err = -EINVAL;
1895                 goto out;
1896         }
1897         strcpy(target, translated);
1898         err = tl_len;
1899
1900 out:
1901         kfree(link_path_buffer);
1902         kfree(translated);
1903         return err;
1904 }
1905
1906 static noinline int ntfs_readlink_hlp(const struct dentry *link_de,
1907                                       struct inode *inode, char *buffer,
1908                                       int buflen)
1909 {
1910         int i, err = -EINVAL;
1911         struct ntfs_inode *ni = ntfs_i(inode);
1912         struct super_block *sb = inode->i_sb;
1913         struct ntfs_sb_info *sbi = sb->s_fs_info;
1914         u64 size;
1915         u16 ulen = 0;
1916         void *to_free = NULL;
1917         struct REPARSE_DATA_BUFFER *rp;
1918         const __le16 *uname;
1919         struct ATTRIB *attr;
1920
1921         /* Reparse data present. Try to parse it. */
1922         static_assert(!offsetof(struct REPARSE_DATA_BUFFER, ReparseTag));
1923         static_assert(sizeof(u32) == sizeof(rp->ReparseTag));
1924
1925         *buffer = 0;
1926
1927         attr = ni_find_attr(ni, NULL, NULL, ATTR_REPARSE, NULL, 0, NULL, NULL);
1928         if (!attr)
1929                 goto out;
1930
1931         if (!attr->non_res) {
1932                 rp = resident_data_ex(attr, sizeof(struct REPARSE_DATA_BUFFER));
1933                 if (!rp)
1934                         goto out;
1935                 size = le32_to_cpu(attr->res.data_size);
1936         } else {
1937                 size = le64_to_cpu(attr->nres.data_size);
1938                 rp = NULL;
1939         }
1940
1941         if (size > sbi->reparse.max_size || size <= sizeof(u32))
1942                 goto out;
1943
1944         if (!rp) {
1945                 rp = kmalloc(size, GFP_NOFS);
1946                 if (!rp) {
1947                         err = -ENOMEM;
1948                         goto out;
1949                 }
1950                 to_free = rp;
1951                 /* Read into temporal buffer. */
1952                 err = ntfs_read_run_nb(sbi, &ni->file.run, 0, rp, size, NULL);
1953                 if (err)
1954                         goto out;
1955         }
1956
1957         /* Microsoft Tag. */
1958         switch (rp->ReparseTag) {
1959         case IO_REPARSE_TAG_MOUNT_POINT:
1960                 /* Mount points and junctions. */
1961                 /* Can we use 'Rp->MountPointReparseBuffer.PrintNameLength'? */
1962                 if (size <= offsetof(struct REPARSE_DATA_BUFFER,
1963                                      MountPointReparseBuffer.PathBuffer))
1964                         goto out;
1965                 uname = Add2Ptr(rp,
1966                                 offsetof(struct REPARSE_DATA_BUFFER,
1967                                          MountPointReparseBuffer.PathBuffer) +
1968                                         le16_to_cpu(rp->MountPointReparseBuffer
1969                                                             .PrintNameOffset));
1970                 ulen = le16_to_cpu(rp->MountPointReparseBuffer.PrintNameLength);
1971                 break;
1972
1973         case IO_REPARSE_TAG_SYMLINK:
1974                 /* FolderSymbolicLink */
1975                 /* Can we use 'Rp->SymbolicLinkReparseBuffer.PrintNameLength'? */
1976                 if (size <= offsetof(struct REPARSE_DATA_BUFFER,
1977                                      SymbolicLinkReparseBuffer.PathBuffer))
1978                         goto out;
1979                 uname = Add2Ptr(
1980                         rp, offsetof(struct REPARSE_DATA_BUFFER,
1981                                      SymbolicLinkReparseBuffer.PathBuffer) +
1982                                     le16_to_cpu(rp->SymbolicLinkReparseBuffer
1983                                                         .PrintNameOffset));
1984                 ulen = le16_to_cpu(
1985                         rp->SymbolicLinkReparseBuffer.PrintNameLength);
1986                 break;
1987
1988         case IO_REPARSE_TAG_CLOUD:
1989         case IO_REPARSE_TAG_CLOUD_1:
1990         case IO_REPARSE_TAG_CLOUD_2:
1991         case IO_REPARSE_TAG_CLOUD_3:
1992         case IO_REPARSE_TAG_CLOUD_4:
1993         case IO_REPARSE_TAG_CLOUD_5:
1994         case IO_REPARSE_TAG_CLOUD_6:
1995         case IO_REPARSE_TAG_CLOUD_7:
1996         case IO_REPARSE_TAG_CLOUD_8:
1997         case IO_REPARSE_TAG_CLOUD_9:
1998         case IO_REPARSE_TAG_CLOUD_A:
1999         case IO_REPARSE_TAG_CLOUD_B:
2000         case IO_REPARSE_TAG_CLOUD_C:
2001         case IO_REPARSE_TAG_CLOUD_D:
2002         case IO_REPARSE_TAG_CLOUD_E:
2003         case IO_REPARSE_TAG_CLOUD_F:
2004                 err = sizeof("OneDrive") - 1;
2005                 if (err > buflen)
2006                         err = buflen;
2007                 memcpy(buffer, "OneDrive", err);
2008                 goto out;
2009
2010         default:
2011                 if (IsReparseTagMicrosoft(rp->ReparseTag)) {
2012                         /* Unknown Microsoft Tag. */
2013                         goto out;
2014                 }
2015                 if (!IsReparseTagNameSurrogate(rp->ReparseTag) ||
2016                     size <= sizeof(struct REPARSE_POINT)) {
2017                         goto out;
2018                 }
2019
2020                 /* Users tag. */
2021                 uname = Add2Ptr(rp, sizeof(struct REPARSE_POINT));
2022                 ulen = le16_to_cpu(rp->ReparseDataLength) -
2023                        sizeof(struct REPARSE_POINT);
2024         }
2025
2026         /* Convert nlen from bytes to UNICODE chars. */
2027         ulen >>= 1;
2028
2029         /* Check that name is available. */
2030         if (!ulen || uname + ulen > (__le16 *)Add2Ptr(rp, size))
2031                 goto out;
2032
2033         /* If name is already zero terminated then truncate it now. */
2034         if (!uname[ulen - 1])
2035                 ulen -= 1;
2036
2037         err = ntfs_utf16_to_nls(sbi, uname, ulen, buffer, buflen);
2038
2039         if (err < 0)
2040                 goto out;
2041
2042         /* Translate Windows '\' into Linux '/'. */
2043         for (i = 0; i < err; i++) {
2044                 if (buffer[i] == '\\')
2045                         buffer[i] = '/';
2046         }
2047
2048         /* Always set last zero. */
2049         buffer[err] = 0;
2050
2051         /* If this is a junction, translate the link target. */
2052         if (rp->ReparseTag == IO_REPARSE_TAG_MOUNT_POINT)
2053                 err = ntfs_translate_junction(sb, link_de, buffer, err, buflen);
2054
2055 out:
2056         kfree(to_free);
2057         return err;
2058 }
2059
2060 static const char *ntfs_get_link(struct dentry *de, struct inode *inode,
2061                                  struct delayed_call *done)
2062 {
2063         int err;
2064         char *ret;
2065
2066         if (!de)
2067                 return ERR_PTR(-ECHILD);
2068
2069         ret = kmalloc(PAGE_SIZE, GFP_NOFS);
2070         if (!ret)
2071                 return ERR_PTR(-ENOMEM);
2072
2073         err = ntfs_readlink_hlp(de, inode, ret, PAGE_SIZE);
2074         if (err < 0) {
2075                 kfree(ret);
2076                 return ERR_PTR(err);
2077         }
2078
2079         set_delayed_call(done, kfree_link, ret);
2080
2081         return ret;
2082 }
2083
2084 // clang-format off
2085 const struct inode_operations ntfs_link_inode_operations = {
2086         .get_link       = ntfs_get_link,
2087         .setattr        = ntfs_setattr,
2088         .listxattr      = ntfs_listxattr,
2089 };
2090
2091 const struct address_space_operations ntfs_aops = {
2092         .read_folio     = ntfs_read_folio,
2093         .readahead      = ntfs_readahead,
2094         .writepages     = ntfs_writepages,
2095         .write_begin    = ntfs_write_begin,
2096         .write_end      = ntfs_write_end,
2097         .direct_IO      = ntfs_direct_IO,
2098         .bmap           = ntfs_bmap,
2099         .dirty_folio    = block_dirty_folio,
2100         .migrate_folio  = buffer_migrate_folio,
2101         .invalidate_folio = block_invalidate_folio,
2102 };
2103
2104 const struct address_space_operations ntfs_aops_cmpr = {
2105         .read_folio     = ntfs_read_folio,
2106         .readahead      = ntfs_readahead,
2107         .dirty_folio    = block_dirty_folio,
2108 };
2109 // clang-format on