fs/erofs/inode.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2017-2018 HUAWEI, Inc.
   4  *             https://www.huawei.com/
   5  * Copyright (C) 2021, Alibaba Cloud
   6  */
   7 #include "xattr.h"
   8
   9 #include <trace/events/erofs.h>
  10
  11 static void *erofs_read_inode(struct erofs_buf *buf,
  12                               struct inode *inode, unsigned int *ofs)
  13 {
  14         struct super_block *sb = inode->i_sb;
  15         struct erofs_sb_info *sbi = EROFS_SB(sb);
  16         struct erofs_inode *vi = EROFS_I(inode);
  17         const erofs_off_t inode_loc = erofs_iloc(inode);
  18
  19         erofs_blk_t blkaddr, nblks = 0;
  20         void *kaddr;
  21         struct erofs_inode_compact *dic;
  22         struct erofs_inode_extended *die, *copied = NULL;
  23         unsigned int ifmt;
  24         int err;
  25
  26         blkaddr = erofs_blknr(sb, inode_loc);
  27         *ofs = erofs_blkoff(sb, inode_loc);
  28
  29         kaddr = erofs_read_metabuf(buf, sb, blkaddr, EROFS_KMAP);
  30         if (IS_ERR(kaddr)) {
  31                 erofs_err(sb, "failed to get inode (nid: %llu) page, err %ld",
  32                           vi->nid, PTR_ERR(kaddr));
  33                 return kaddr;
  34         }
  35
  36         dic = kaddr + *ofs;
  37         ifmt = le16_to_cpu(dic->i_format);
  38
  39         if (ifmt & ~EROFS_I_ALL) {
  40                 erofs_err(inode->i_sb, "unsupported i_format %u of nid %llu",
  41                           ifmt, vi->nid);
  42                 err = -EOPNOTSUPP;
  43                 goto err_out;
  44         }
  45
  46         vi->datalayout = erofs_inode_datalayout(ifmt);
  47         if (vi->datalayout >= EROFS_INODE_DATALAYOUT_MAX) {
  48                 erofs_err(inode->i_sb, "unsupported datalayout %u of nid %llu",
  49                           vi->datalayout, vi->nid);
  50                 err = -EOPNOTSUPP;
  51                 goto err_out;
  52         }
  53
  54         switch (erofs_inode_version(ifmt)) {
  55         case EROFS_INODE_LAYOUT_EXTENDED:
  56                 vi->inode_isize = sizeof(struct erofs_inode_extended);
  57                 /* check if the extended inode acrosses block boundary */
  58                 if (*ofs + vi->inode_isize <= sb->s_blocksize) {
  59                         *ofs += vi->inode_isize;
  60                         die = (struct erofs_inode_extended *)dic;
  61                 } else {
  62                         const unsigned int gotten = sb->s_blocksize - *ofs;
  63
  64                         copied = kmalloc(vi->inode_isize, GFP_NOFS);
  65                         if (!copied) {
  66                                 err = -ENOMEM;
  67                                 goto err_out;
  68                         }
  69                         memcpy(copied, dic, gotten);
  70                         kaddr = erofs_read_metabuf(buf, sb, blkaddr + 1,
  71                                                    EROFS_KMAP);
  72                         if (IS_ERR(kaddr)) {
  73                                 erofs_err(sb, "failed to get inode payload block (nid: %llu), err %ld",
  74                                           vi->nid, PTR_ERR(kaddr));
  75                                 kfree(copied);
  76                                 return kaddr;
  77                         }
  78                         *ofs = vi->inode_isize - gotten;
  79                         memcpy((u8 *)copied + gotten, kaddr, *ofs);
  80                         die = copied;
  81                 }
  82                 vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount);
  83
  84                 inode->i_mode = le16_to_cpu(die->i_mode);
  85                 switch (inode->i_mode & S_IFMT) {
  86                 case S_IFREG:
  87                 case S_IFDIR:
  88                 case S_IFLNK:
  89                         vi->raw_blkaddr = le32_to_cpu(die->i_u.raw_blkaddr);
  90                         break;
  91                 case S_IFCHR:
  92                 case S_IFBLK:
  93                         inode->i_rdev =
  94                                 new_decode_dev(le32_to_cpu(die->i_u.rdev));
  95                         break;
  96                 case S_IFIFO:
  97                 case S_IFSOCK:
  98                         inode->i_rdev = 0;
  99                         break;
 100                 default:
 101                         goto bogusimode;
 102                 }
 103                 i_uid_write(inode, le32_to_cpu(die->i_uid));
 104                 i_gid_write(inode, le32_to_cpu(die->i_gid));
 105                 set_nlink(inode, le32_to_cpu(die->i_nlink));
 106
 107                 /* extended inode has its own timestamp */
 108                 inode->i_ctime.tv_sec = le64_to_cpu(die->i_mtime);
 109                 inode->i_ctime.tv_nsec = le32_to_cpu(die->i_mtime_nsec);
 110
 111                 inode->i_size = le64_to_cpu(die->i_size);
 112
 113                 /* total blocks for compressed files */
 114                 if (erofs_inode_is_data_compressed(vi->datalayout))
 115                         nblks = le32_to_cpu(die->i_u.compressed_blocks);
 116                 else if (vi->datalayout == EROFS_INODE_CHUNK_BASED)
 117                         /* fill chunked inode summary info */
 118                         vi->chunkformat = le16_to_cpu(die->i_u.c.format);
 119                 kfree(copied);
 120                 copied = NULL;
 121                 break;
 122         case EROFS_INODE_LAYOUT_COMPACT:
 123                 vi->inode_isize = sizeof(struct erofs_inode_compact);
 124                 *ofs += vi->inode_isize;
 125                 vi->xattr_isize = erofs_xattr_ibody_size(dic->i_xattr_icount);
 126
 127                 inode->i_mode = le16_to_cpu(dic->i_mode);
 128                 switch (inode->i_mode & S_IFMT) {
 129                 case S_IFREG:
 130                 case S_IFDIR:
 131                 case S_IFLNK:
 132                         vi->raw_blkaddr = le32_to_cpu(dic->i_u.raw_blkaddr);
 133                         break;
 134                 case S_IFCHR:
 135                 case S_IFBLK:
 136                         inode->i_rdev =
 137                                 new_decode_dev(le32_to_cpu(dic->i_u.rdev));
 138                         break;
 139                 case S_IFIFO:
 140                 case S_IFSOCK:
 141                         inode->i_rdev = 0;
 142                         break;
 143                 default:
 144                         goto bogusimode;
 145                 }
 146                 i_uid_write(inode, le16_to_cpu(dic->i_uid));
 147                 i_gid_write(inode, le16_to_cpu(dic->i_gid));
 148                 set_nlink(inode, le16_to_cpu(dic->i_nlink));
 149
 150                 /* use build time for compact inodes */
 151                 inode->i_ctime.tv_sec = sbi->build_time;
 152                 inode->i_ctime.tv_nsec = sbi->build_time_nsec;
 153
 154                 inode->i_size = le32_to_cpu(dic->i_size);
 155                 if (erofs_inode_is_data_compressed(vi->datalayout))
 156                         nblks = le32_to_cpu(dic->i_u.compressed_blocks);
 157                 else if (vi->datalayout == EROFS_INODE_CHUNK_BASED)
 158                         vi->chunkformat = le16_to_cpu(dic->i_u.c.format);
 159                 break;
 160         default:
 161                 erofs_err(inode->i_sb,
 162                           "unsupported on-disk inode version %u of nid %llu",
 163                           erofs_inode_version(ifmt), vi->nid);
 164                 err = -EOPNOTSUPP;
 165                 goto err_out;
 166         }
 167
 168         if (vi->datalayout == EROFS_INODE_CHUNK_BASED) {
 169                 if (vi->chunkformat & ~EROFS_CHUNK_FORMAT_ALL) {
 170                         erofs_err(inode->i_sb,
 171                                   "unsupported chunk format %x of nid %llu",
 172                                   vi->chunkformat, vi->nid);
 173                         err = -EOPNOTSUPP;
 174                         goto err_out;
 175                 }
 176                 vi->chunkbits = sb->s_blocksize_bits +
 177                         (vi->chunkformat & EROFS_CHUNK_FORMAT_BLKBITS_MASK);
 178         }
 179         inode->i_mtime.tv_sec = inode->i_ctime.tv_sec;
 180         inode->i_atime.tv_sec = inode->i_ctime.tv_sec;
 181         inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec;
 182         inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec;
 183
 184         inode->i_flags &= ~S_DAX;
 185         if (test_opt(&sbi->opt, DAX_ALWAYS) && S_ISREG(inode->i_mode) &&
 186             (vi->datalayout == EROFS_INODE_FLAT_PLAIN ||
 187              vi->datalayout == EROFS_INODE_CHUNK_BASED))
 188                 inode->i_flags |= S_DAX;
 189
 190         if (!nblks)
 191                 /* measure inode.i_blocks as generic filesystems */
 192                 inode->i_blocks = round_up(inode->i_size, sb->s_blocksize) >> 9;
 193         else
 194                 inode->i_blocks = nblks << (sb->s_blocksize_bits - 9);
 195         return kaddr;
 196
 197 bogusimode:
 198         erofs_err(inode->i_sb, "bogus i_mode (%o) @ nid %llu",
 199                   inode->i_mode, vi->nid);
 200         err = -EFSCORRUPTED;
 201 err_out:
 202         DBG_BUGON(1);
 203         kfree(copied);
 204         erofs_put_metabuf(buf);
 205         return ERR_PTR(err);
 206 }
 207
 208 static int erofs_fill_symlink(struct inode *inode, void *kaddr,
 209                               unsigned int m_pofs)
 210 {
 211         struct erofs_inode *vi = EROFS_I(inode);
 212         unsigned int bsz = i_blocksize(inode);
 213         char *lnk;
 214
 215         /* if it cannot be handled with fast symlink scheme */
 216         if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||
 217             inode->i_size >= bsz || inode->i_size < 0) {
 218                 inode->i_op = &erofs_symlink_iops;
 219                 return 0;
 220         }
 221
 222         lnk = kmalloc(inode->i_size + 1, GFP_KERNEL);
 223         if (!lnk)
 224                 return -ENOMEM;
 225
 226         m_pofs += vi->xattr_isize;
 227         /* inline symlink data shouldn't cross block boundary */
 228         if (m_pofs + inode->i_size > bsz) {
 229                 kfree(lnk);
 230                 erofs_err(inode->i_sb,
 231                           "inline data cross block boundary @ nid %llu",
 232                           vi->nid);
 233                 DBG_BUGON(1);
 234                 return -EFSCORRUPTED;
 235         }
 236         memcpy(lnk, kaddr + m_pofs, inode->i_size);
 237         lnk[inode->i_size] = '\0';
 238
 239         inode->i_link = lnk;
 240         inode->i_op = &erofs_fast_symlink_iops;
 241         return 0;
 242 }
 243
 244 static int erofs_fill_inode(struct inode *inode)
 245 {
 246         struct erofs_inode *vi = EROFS_I(inode);
 247         struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
 248         void *kaddr;
 249         unsigned int ofs;
 250         int err = 0;
 251
 252         trace_erofs_fill_inode(inode);
 253
 254         /* read inode base data from disk */
 255         kaddr = erofs_read_inode(&buf, inode, &ofs);
 256         if (IS_ERR(kaddr))
 257                 return PTR_ERR(kaddr);
 258
 259         /* setup the new inode */
 260         switch (inode->i_mode & S_IFMT) {
 261         case S_IFREG:
 262                 inode->i_op = &erofs_generic_iops;
 263                 if (erofs_inode_is_data_compressed(vi->datalayout))
 264                         inode->i_fop = &generic_ro_fops;
 265                 else
 266                         inode->i_fop = &erofs_file_fops;
 267                 break;
 268         case S_IFDIR:
 269                 inode->i_op = &erofs_dir_iops;
 270                 inode->i_fop = &erofs_dir_fops;
 271                 inode_nohighmem(inode);
 272                 break;
 273         case S_IFLNK:
 274                 err = erofs_fill_symlink(inode, kaddr, ofs);
 275                 if (err)
 276                         goto out_unlock;
 277                 inode_nohighmem(inode);
 278                 break;
 279         case S_IFCHR:
 280         case S_IFBLK:
 281         case S_IFIFO:
 282         case S_IFSOCK:
 283                 inode->i_op = &erofs_generic_iops;
 284                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
 285                 goto out_unlock;
 286         default:
 287                 err = -EFSCORRUPTED;
 288                 goto out_unlock;
 289         }
 290
 291         if (erofs_inode_is_data_compressed(vi->datalayout)) {
 292 #ifdef CONFIG_EROFS_FS_ZIP
 293                 if (!erofs_is_fscache_mode(inode->i_sb) &&
 294                     inode->i_sb->s_blocksize_bits == PAGE_SHIFT) {
 295                         inode->i_mapping->a_ops = &z_erofs_aops;
 296                         err = 0;
 297                         goto out_unlock;
 298                 }
 299 #endif
 300                 err = -EOPNOTSUPP;
 301                 goto out_unlock;
 302         }
 303         inode->i_mapping->a_ops = &erofs_raw_access_aops;
 304         mapping_set_large_folios(inode->i_mapping);
 305 #ifdef CONFIG_EROFS_FS_ONDEMAND
 306         if (erofs_is_fscache_mode(inode->i_sb))
 307                 inode->i_mapping->a_ops = &erofs_fscache_access_aops;
 308 #endif
 309
 310 out_unlock:
 311         erofs_put_metabuf(&buf);
 312         return err;
 313 }
 314
 315 /*
 316  * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
 317  * so that it will fit.
 318  */
 319 static ino_t erofs_squash_ino(erofs_nid_t nid)
 320 {
 321         ino_t ino = (ino_t)nid;
 322
 323         if (sizeof(ino_t) < sizeof(erofs_nid_t))
 324                 ino ^= nid >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8;
 325         return ino;
 326 }
 327
 328 static int erofs_iget5_eq(struct inode *inode, void *opaque)
 329 {
 330         return EROFS_I(inode)->nid == *(erofs_nid_t *)opaque;
 331 }
 332
 333 static int erofs_iget5_set(struct inode *inode, void *opaque)
 334 {
 335         const erofs_nid_t nid = *(erofs_nid_t *)opaque;
 336
 337         inode->i_ino = erofs_squash_ino(nid);
 338         EROFS_I(inode)->nid = nid;
 339         return 0;
 340 }
 341
 342 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid)
 343 {
 344         struct inode *inode;
 345
 346         inode = iget5_locked(sb, erofs_squash_ino(nid), erofs_iget5_eq,
 347                              erofs_iget5_set, &nid);
 348         if (!inode)
 349                 return ERR_PTR(-ENOMEM);
 350
 351         if (inode->i_state & I_NEW) {
 352                 int err = erofs_fill_inode(inode);
 353
 354                 if (err) {
 355                         iget_failed(inode);
 356                         return ERR_PTR(err);
 357                 }
 358                 unlock_new_inode(inode);
 359         }
 360         return inode;
 361 }
 362
 363 int erofs_getattr(struct mnt_idmap *idmap, const struct path *path,
 364                   struct kstat *stat, u32 request_mask,
 365                   unsigned int query_flags)
 366 {
 367         struct inode *const inode = d_inode(path->dentry);
 368
 369         if (erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout))
 370                 stat->attributes |= STATX_ATTR_COMPRESSED;
 371
 372         stat->attributes |= STATX_ATTR_IMMUTABLE;
 373         stat->attributes_mask |= (STATX_ATTR_COMPRESSED |
 374                                   STATX_ATTR_IMMUTABLE);
 375
 376         generic_fillattr(idmap, inode, stat);
 377         return 0;
 378 }
 379
 380 const struct inode_operations erofs_generic_iops = {
 381         .getattr = erofs_getattr,
 382         .listxattr = erofs_listxattr,
 383         .get_inode_acl = erofs_get_acl,
 384         .fiemap = erofs_fiemap,
 385 };
 386
 387 const struct inode_operations erofs_symlink_iops = {
 388         .get_link = page_get_link,
 389         .getattr = erofs_getattr,
 390         .listxattr = erofs_listxattr,
 391         .get_inode_acl = erofs_get_acl,
 392 };
 393
 394 const struct inode_operations erofs_fast_symlink_iops = {
 395         .get_link = simple_get_link,
 396         .getattr = erofs_getattr,
 397         .listxattr = erofs_listxattr,
 398         .get_inode_acl = erofs_get_acl,
 399 };