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 #ifndef __EROFS_INTERNAL_H 8 #define __EROFS_INTERNAL_H 9 10 #include <linux/fs.h> 11 #include <linux/dcache.h> 12 #include <linux/mm.h> 13 #include <linux/pagemap.h> 14 #include <linux/bio.h> 15 #include <linux/buffer_head.h> 16 #include <linux/magic.h> 17 #include <linux/slab.h> 18 #include <linux/vmalloc.h> 19 #include <linux/iomap.h> 20 #include "erofs_fs.h" 21 22 /* redefine pr_fmt "erofs: " */ 23 #undef pr_fmt 24 #define pr_fmt(fmt) "erofs: " fmt 25 26 __printf(3, 4) void _erofs_err(struct super_block *sb, 27 const char *function, const char *fmt, ...); 28 #define erofs_err(sb, fmt, ...) \ 29 _erofs_err(sb, __func__, fmt "\n", ##__VA_ARGS__) 30 __printf(3, 4) void _erofs_info(struct super_block *sb, 31 const char *function, const char *fmt, ...); 32 #define erofs_info(sb, fmt, ...) \ 33 _erofs_info(sb, __func__, fmt "\n", ##__VA_ARGS__) 34 #ifdef CONFIG_EROFS_FS_DEBUG 35 #define erofs_dbg(x, ...) pr_debug(x "\n", ##__VA_ARGS__) 36 #define DBG_BUGON BUG_ON 37 #else 38 #define erofs_dbg(x, ...) ((void)0) 39 #define DBG_BUGON(x) ((void)(x)) 40 #endif /* !CONFIG_EROFS_FS_DEBUG */ 41 42 /* EROFS_SUPER_MAGIC_V1 to represent the whole file system */ 43 #define EROFS_SUPER_MAGIC EROFS_SUPER_MAGIC_V1 44 45 typedef u64 erofs_nid_t; 46 typedef u64 erofs_off_t; 47 /* data type for filesystem-wide blocks number */ 48 typedef u32 erofs_blk_t; 49 50 struct erofs_device_info { 51 char *path; 52 struct erofs_fscache *fscache; 53 struct block_device *bdev; 54 struct dax_device *dax_dev; 55 u64 dax_part_off; 56 57 u32 blocks; 58 u32 mapped_blkaddr; 59 }; 60 61 enum { 62 EROFS_SYNC_DECOMPRESS_AUTO, 63 EROFS_SYNC_DECOMPRESS_FORCE_ON, 64 EROFS_SYNC_DECOMPRESS_FORCE_OFF 65 }; 66 67 struct erofs_mount_opts { 68 #ifdef CONFIG_EROFS_FS_ZIP 69 /* current strategy of how to use managed cache */ 70 unsigned char cache_strategy; 71 /* strategy of sync decompression (0 - auto, 1 - force on, 2 - force off) */ 72 unsigned int sync_decompress; 73 74 /* threshold for decompression synchronously */ 75 unsigned int max_sync_decompress_pages; 76 #endif 77 unsigned int mount_opt; 78 }; 79 80 struct erofs_dev_context { 81 struct idr tree; 82 struct rw_semaphore rwsem; 83 84 unsigned int extra_devices; 85 }; 86 87 struct erofs_fs_context { 88 struct erofs_mount_opts opt; 89 struct erofs_dev_context *devs; 90 char *fsid; 91 char *domain_id; 92 }; 93 94 /* all filesystem-wide lz4 configurations */ 95 struct erofs_sb_lz4_info { 96 /* # of pages needed for EROFS lz4 rolling decompression */ 97 u16 max_distance_pages; 98 /* maximum possible blocks for pclusters in the filesystem */ 99 u16 max_pclusterblks; 100 }; 101 102 struct erofs_domain { 103 refcount_t ref; 104 struct list_head list; 105 struct fscache_volume *volume; 106 char *domain_id; 107 }; 108 109 struct erofs_fscache { 110 struct fscache_cookie *cookie; 111 struct inode *inode; 112 struct inode *anon_inode; 113 struct erofs_domain *domain; 114 char *name; 115 }; 116 117 struct erofs_sb_info { 118 struct erofs_mount_opts opt; /* options */ 119 #ifdef CONFIG_EROFS_FS_ZIP 120 /* list for all registered superblocks, mainly for shrinker */ 121 struct list_head list; 122 struct mutex umount_mutex; 123 124 /* managed XArray arranged in physical block number */ 125 struct xarray managed_pslots; 126 127 unsigned int shrinker_run_no; 128 u16 available_compr_algs; 129 130 /* pseudo inode to manage cached pages */ 131 struct inode *managed_cache; 132 133 struct erofs_sb_lz4_info lz4; 134 struct inode *packed_inode; 135 #endif /* CONFIG_EROFS_FS_ZIP */ 136 struct erofs_dev_context *devs; 137 struct dax_device *dax_dev; 138 u64 dax_part_off; 139 u64 total_blocks; 140 u32 primarydevice_blocks; 141 142 u32 meta_blkaddr; 143 #ifdef CONFIG_EROFS_FS_XATTR 144 u32 xattr_blkaddr; 145 #endif 146 u16 device_id_mask; /* valid bits of device id to be used */ 147 148 /* inode slot unit size in bit shift */ 149 unsigned char islotbits; 150 151 u32 sb_size; /* total superblock size */ 152 u32 build_time_nsec; 153 u64 build_time; 154 155 /* what we really care is nid, rather than ino.. */ 156 erofs_nid_t root_nid; 157 /* used for statfs, f_files - f_favail */ 158 u64 inos; 159 160 u8 uuid[16]; /* 128-bit uuid for volume */ 161 u8 volume_name[16]; /* volume name */ 162 u32 feature_compat; 163 u32 feature_incompat; 164 165 /* sysfs support */ 166 struct kobject s_kobj; /* /sys/fs/erofs/<devname> */ 167 struct completion s_kobj_unregister; 168 169 /* fscache support */ 170 struct fscache_volume *volume; 171 struct erofs_fscache *s_fscache; 172 struct erofs_domain *domain; 173 char *fsid; 174 char *domain_id; 175 }; 176 177 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info) 178 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info) 179 180 /* Mount flags set via mount options or defaults */ 181 #define EROFS_MOUNT_XATTR_USER 0x00000010 182 #define EROFS_MOUNT_POSIX_ACL 0x00000020 183 #define EROFS_MOUNT_DAX_ALWAYS 0x00000040 184 #define EROFS_MOUNT_DAX_NEVER 0x00000080 185 186 #define clear_opt(opt, option) ((opt)->mount_opt &= ~EROFS_MOUNT_##option) 187 #define set_opt(opt, option) ((opt)->mount_opt |= EROFS_MOUNT_##option) 188 #define test_opt(opt, option) ((opt)->mount_opt & EROFS_MOUNT_##option) 189 190 static inline bool erofs_is_fscache_mode(struct super_block *sb) 191 { 192 return IS_ENABLED(CONFIG_EROFS_FS_ONDEMAND) && !sb->s_bdev; 193 } 194 195 enum { 196 EROFS_ZIP_CACHE_DISABLED, 197 EROFS_ZIP_CACHE_READAHEAD, 198 EROFS_ZIP_CACHE_READAROUND 199 }; 200 201 #define EROFS_LOCKED_MAGIC (INT_MIN | 0xE0F510CCL) 202 203 /* basic unit of the workstation of a super_block */ 204 struct erofs_workgroup { 205 /* the workgroup index in the workstation */ 206 pgoff_t index; 207 208 /* overall workgroup reference count */ 209 atomic_t refcount; 210 }; 211 212 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp, 213 int val) 214 { 215 preempt_disable(); 216 if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) { 217 preempt_enable(); 218 return false; 219 } 220 return true; 221 } 222 223 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp, 224 int orig_val) 225 { 226 /* 227 * other observers should notice all modifications 228 * in the freezing period. 229 */ 230 smp_mb(); 231 atomic_set(&grp->refcount, orig_val); 232 preempt_enable(); 233 } 234 235 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp) 236 { 237 return atomic_cond_read_relaxed(&grp->refcount, 238 VAL != EROFS_LOCKED_MAGIC); 239 } 240 241 /* we strictly follow PAGE_SIZE and no buffer head yet */ 242 #define LOG_BLOCK_SIZE PAGE_SHIFT 243 244 #undef LOG_SECTORS_PER_BLOCK 245 #define LOG_SECTORS_PER_BLOCK (PAGE_SHIFT - 9) 246 247 #undef SECTORS_PER_BLOCK 248 #define SECTORS_PER_BLOCK (1 << SECTORS_PER_BLOCK) 249 250 #define EROFS_BLKSIZ (1 << LOG_BLOCK_SIZE) 251 252 #if (EROFS_BLKSIZ % 4096 || !EROFS_BLKSIZ) 253 #error erofs cannot be used in this platform 254 #endif 255 256 enum erofs_kmap_type { 257 EROFS_NO_KMAP, /* don't map the buffer */ 258 EROFS_KMAP, /* use kmap_local_page() to map the buffer */ 259 }; 260 261 struct erofs_buf { 262 struct page *page; 263 void *base; 264 enum erofs_kmap_type kmap_type; 265 }; 266 #define __EROFS_BUF_INITIALIZER ((struct erofs_buf){ .page = NULL }) 267 268 #define ROOT_NID(sb) ((sb)->root_nid) 269 270 #define erofs_blknr(addr) ((addr) / EROFS_BLKSIZ) 271 #define erofs_blkoff(addr) ((addr) % EROFS_BLKSIZ) 272 #define blknr_to_addr(nr) ((erofs_off_t)(nr) * EROFS_BLKSIZ) 273 274 static inline erofs_off_t iloc(struct erofs_sb_info *sbi, erofs_nid_t nid) 275 { 276 return blknr_to_addr(sbi->meta_blkaddr) + (nid << sbi->islotbits); 277 } 278 279 #define EROFS_FEATURE_FUNCS(name, compat, feature) \ 280 static inline bool erofs_sb_has_##name(struct erofs_sb_info *sbi) \ 281 { \ 282 return sbi->feature_##compat & EROFS_FEATURE_##feature; \ 283 } 284 285 EROFS_FEATURE_FUNCS(zero_padding, incompat, INCOMPAT_ZERO_PADDING) 286 EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS) 287 EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER) 288 EROFS_FEATURE_FUNCS(chunked_file, incompat, INCOMPAT_CHUNKED_FILE) 289 EROFS_FEATURE_FUNCS(device_table, incompat, INCOMPAT_DEVICE_TABLE) 290 EROFS_FEATURE_FUNCS(compr_head2, incompat, INCOMPAT_COMPR_HEAD2) 291 EROFS_FEATURE_FUNCS(ztailpacking, incompat, INCOMPAT_ZTAILPACKING) 292 EROFS_FEATURE_FUNCS(fragments, incompat, INCOMPAT_FRAGMENTS) 293 EROFS_FEATURE_FUNCS(dedupe, incompat, INCOMPAT_DEDUPE) 294 EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM) 295 296 /* atomic flag definitions */ 297 #define EROFS_I_EA_INITED_BIT 0 298 #define EROFS_I_Z_INITED_BIT 1 299 300 /* bitlock definitions (arranged in reverse order) */ 301 #define EROFS_I_BL_XATTR_BIT (BITS_PER_LONG - 1) 302 #define EROFS_I_BL_Z_BIT (BITS_PER_LONG - 2) 303 304 struct erofs_inode { 305 erofs_nid_t nid; 306 307 /* atomic flags (including bitlocks) */ 308 unsigned long flags; 309 310 unsigned char datalayout; 311 unsigned char inode_isize; 312 unsigned short xattr_isize; 313 314 unsigned int xattr_shared_count; 315 unsigned int *xattr_shared_xattrs; 316 317 union { 318 erofs_blk_t raw_blkaddr; 319 struct { 320 unsigned short chunkformat; 321 unsigned char chunkbits; 322 }; 323 #ifdef CONFIG_EROFS_FS_ZIP 324 struct { 325 unsigned short z_advise; 326 unsigned char z_algorithmtype[2]; 327 unsigned char z_logical_clusterbits; 328 unsigned long z_tailextent_headlcn; 329 union { 330 struct { 331 erofs_off_t z_idataoff; 332 unsigned short z_idata_size; 333 }; 334 erofs_off_t z_fragmentoff; 335 }; 336 }; 337 #endif /* CONFIG_EROFS_FS_ZIP */ 338 }; 339 /* the corresponding vfs inode */ 340 struct inode vfs_inode; 341 }; 342 343 #define EROFS_I(ptr) \ 344 container_of(ptr, struct erofs_inode, vfs_inode) 345 346 static inline unsigned long erofs_inode_datablocks(struct inode *inode) 347 { 348 /* since i_size cannot be changed */ 349 return DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ); 350 } 351 352 static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit, 353 unsigned int bits) 354 { 355 356 return (value >> bit) & ((1 << bits) - 1); 357 } 358 359 360 static inline unsigned int erofs_inode_version(unsigned int value) 361 { 362 return erofs_bitrange(value, EROFS_I_VERSION_BIT, 363 EROFS_I_VERSION_BITS); 364 } 365 366 static inline unsigned int erofs_inode_datalayout(unsigned int value) 367 { 368 return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT, 369 EROFS_I_DATALAYOUT_BITS); 370 } 371 372 /* 373 * Different from grab_cache_page_nowait(), reclaiming is never triggered 374 * when allocating new pages. 375 */ 376 static inline 377 struct page *erofs_grab_cache_page_nowait(struct address_space *mapping, 378 pgoff_t index) 379 { 380 return pagecache_get_page(mapping, index, 381 FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT, 382 readahead_gfp_mask(mapping) & ~__GFP_RECLAIM); 383 } 384 385 extern const struct super_operations erofs_sops; 386 extern struct file_system_type erofs_fs_type; 387 388 extern const struct address_space_operations erofs_raw_access_aops; 389 extern const struct address_space_operations z_erofs_aops; 390 391 enum { 392 BH_Encoded = BH_PrivateStart, 393 BH_FullMapped, 394 BH_Fragment, 395 BH_Partialref, 396 }; 397 398 /* Has a disk mapping */ 399 #define EROFS_MAP_MAPPED (1 << BH_Mapped) 400 /* Located in metadata (could be copied from bd_inode) */ 401 #define EROFS_MAP_META (1 << BH_Meta) 402 /* The extent is encoded */ 403 #define EROFS_MAP_ENCODED (1 << BH_Encoded) 404 /* The length of extent is full */ 405 #define EROFS_MAP_FULL_MAPPED (1 << BH_FullMapped) 406 /* Located in the special packed inode */ 407 #define EROFS_MAP_FRAGMENT (1 << BH_Fragment) 408 /* The extent refers to partial decompressed data */ 409 #define EROFS_MAP_PARTIAL_REF (1 << BH_Partialref) 410 411 struct erofs_map_blocks { 412 struct erofs_buf buf; 413 414 erofs_off_t m_pa, m_la; 415 u64 m_plen, m_llen; 416 417 unsigned short m_deviceid; 418 char m_algorithmformat; 419 unsigned int m_flags; 420 }; 421 422 /* Flags used by erofs_map_blocks_flatmode() */ 423 #define EROFS_GET_BLOCKS_RAW 0x0001 424 /* 425 * Used to get the exact decompressed length, e.g. fiemap (consider lookback 426 * approach instead if possible since it's more metadata lightweight.) 427 */ 428 #define EROFS_GET_BLOCKS_FIEMAP 0x0002 429 /* Used to map the whole extent if non-negligible data is requested for LZMA */ 430 #define EROFS_GET_BLOCKS_READMORE 0x0004 431 /* Used to map tail extent for tailpacking inline or fragment pcluster */ 432 #define EROFS_GET_BLOCKS_FINDTAIL 0x0008 433 434 enum { 435 Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX, 436 Z_EROFS_COMPRESSION_INTERLACED, 437 Z_EROFS_COMPRESSION_RUNTIME_MAX 438 }; 439 440 /* zmap.c */ 441 extern const struct iomap_ops z_erofs_iomap_report_ops; 442 443 #ifdef CONFIG_EROFS_FS_ZIP 444 int z_erofs_fill_inode(struct inode *inode); 445 int z_erofs_map_blocks_iter(struct inode *inode, 446 struct erofs_map_blocks *map, 447 int flags); 448 #else 449 static inline int z_erofs_fill_inode(struct inode *inode) { return -EOPNOTSUPP; } 450 static inline int z_erofs_map_blocks_iter(struct inode *inode, 451 struct erofs_map_blocks *map, 452 int flags) 453 { 454 return -EOPNOTSUPP; 455 } 456 #endif /* !CONFIG_EROFS_FS_ZIP */ 457 458 struct erofs_map_dev { 459 struct erofs_fscache *m_fscache; 460 struct block_device *m_bdev; 461 struct dax_device *m_daxdev; 462 u64 m_dax_part_off; 463 464 erofs_off_t m_pa; 465 unsigned int m_deviceid; 466 }; 467 468 /* data.c */ 469 extern const struct file_operations erofs_file_fops; 470 void erofs_unmap_metabuf(struct erofs_buf *buf); 471 void erofs_put_metabuf(struct erofs_buf *buf); 472 void *erofs_bread(struct erofs_buf *buf, struct inode *inode, 473 erofs_blk_t blkaddr, enum erofs_kmap_type type); 474 void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb, 475 erofs_blk_t blkaddr, enum erofs_kmap_type type); 476 int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *dev); 477 int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, 478 u64 start, u64 len); 479 int erofs_map_blocks(struct inode *inode, 480 struct erofs_map_blocks *map, int flags); 481 482 /* inode.c */ 483 static inline unsigned long erofs_inode_hash(erofs_nid_t nid) 484 { 485 #if BITS_PER_LONG == 32 486 return (nid >> 32) ^ (nid & 0xffffffff); 487 #else 488 return nid; 489 #endif 490 } 491 492 extern const struct inode_operations erofs_generic_iops; 493 extern const struct inode_operations erofs_symlink_iops; 494 extern const struct inode_operations erofs_fast_symlink_iops; 495 496 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid); 497 int erofs_getattr(struct user_namespace *mnt_userns, const struct path *path, 498 struct kstat *stat, u32 request_mask, 499 unsigned int query_flags); 500 501 /* namei.c */ 502 extern const struct inode_operations erofs_dir_iops; 503 504 int erofs_namei(struct inode *dir, const struct qstr *name, 505 erofs_nid_t *nid, unsigned int *d_type); 506 507 /* dir.c */ 508 extern const struct file_operations erofs_dir_fops; 509 510 static inline void *erofs_vm_map_ram(struct page **pages, unsigned int count) 511 { 512 int retried = 0; 513 514 while (1) { 515 void *p = vm_map_ram(pages, count, -1); 516 517 /* retry two more times (totally 3 times) */ 518 if (p || ++retried >= 3) 519 return p; 520 vm_unmap_aliases(); 521 } 522 return NULL; 523 } 524 525 /* pcpubuf.c */ 526 void *erofs_get_pcpubuf(unsigned int requiredpages); 527 void erofs_put_pcpubuf(void *ptr); 528 int erofs_pcpubuf_growsize(unsigned int nrpages); 529 void erofs_pcpubuf_init(void); 530 void erofs_pcpubuf_exit(void); 531 532 /* sysfs.c */ 533 int erofs_register_sysfs(struct super_block *sb); 534 void erofs_unregister_sysfs(struct super_block *sb); 535 int __init erofs_init_sysfs(void); 536 void erofs_exit_sysfs(void); 537 538 /* utils.c / zdata.c */ 539 struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp); 540 static inline void erofs_pagepool_add(struct page **pagepool, 541 struct page *page) 542 { 543 set_page_private(page, (unsigned long)*pagepool); 544 *pagepool = page; 545 } 546 void erofs_release_pages(struct page **pagepool); 547 548 #ifdef CONFIG_EROFS_FS_ZIP 549 int erofs_workgroup_put(struct erofs_workgroup *grp); 550 struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb, 551 pgoff_t index); 552 struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb, 553 struct erofs_workgroup *grp); 554 void erofs_workgroup_free_rcu(struct erofs_workgroup *grp); 555 void erofs_shrinker_register(struct super_block *sb); 556 void erofs_shrinker_unregister(struct super_block *sb); 557 int __init erofs_init_shrinker(void); 558 void erofs_exit_shrinker(void); 559 int __init z_erofs_init_zip_subsystem(void); 560 void z_erofs_exit_zip_subsystem(void); 561 int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi, 562 struct erofs_workgroup *egrp); 563 int erofs_try_to_free_cached_page(struct page *page); 564 int z_erofs_load_lz4_config(struct super_block *sb, 565 struct erofs_super_block *dsb, 566 struct z_erofs_lz4_cfgs *lz4, int len); 567 #else 568 static inline void erofs_shrinker_register(struct super_block *sb) {} 569 static inline void erofs_shrinker_unregister(struct super_block *sb) {} 570 static inline int erofs_init_shrinker(void) { return 0; } 571 static inline void erofs_exit_shrinker(void) {} 572 static inline int z_erofs_init_zip_subsystem(void) { return 0; } 573 static inline void z_erofs_exit_zip_subsystem(void) {} 574 static inline int z_erofs_load_lz4_config(struct super_block *sb, 575 struct erofs_super_block *dsb, 576 struct z_erofs_lz4_cfgs *lz4, int len) 577 { 578 if (lz4 || dsb->u1.lz4_max_distance) { 579 erofs_err(sb, "lz4 algorithm isn't enabled"); 580 return -EINVAL; 581 } 582 return 0; 583 } 584 #endif /* !CONFIG_EROFS_FS_ZIP */ 585 586 #ifdef CONFIG_EROFS_FS_ZIP_LZMA 587 int z_erofs_lzma_init(void); 588 void z_erofs_lzma_exit(void); 589 int z_erofs_load_lzma_config(struct super_block *sb, 590 struct erofs_super_block *dsb, 591 struct z_erofs_lzma_cfgs *lzma, int size); 592 #else 593 static inline int z_erofs_lzma_init(void) { return 0; } 594 static inline int z_erofs_lzma_exit(void) { return 0; } 595 static inline int z_erofs_load_lzma_config(struct super_block *sb, 596 struct erofs_super_block *dsb, 597 struct z_erofs_lzma_cfgs *lzma, int size) { 598 if (lzma) { 599 erofs_err(sb, "lzma algorithm isn't enabled"); 600 return -EINVAL; 601 } 602 return 0; 603 } 604 #endif /* !CONFIG_EROFS_FS_ZIP */ 605 606 /* flags for erofs_fscache_register_cookie() */ 607 #define EROFS_REG_COOKIE_NEED_INODE 1 608 #define EROFS_REG_COOKIE_NEED_NOEXIST 2 609 610 /* fscache.c */ 611 #ifdef CONFIG_EROFS_FS_ONDEMAND 612 int erofs_fscache_register_fs(struct super_block *sb); 613 void erofs_fscache_unregister_fs(struct super_block *sb); 614 615 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb, 616 char *name, 617 unsigned int flags); 618 void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache); 619 620 extern const struct address_space_operations erofs_fscache_access_aops; 621 #else 622 static inline int erofs_fscache_register_fs(struct super_block *sb) 623 { 624 return -EOPNOTSUPP; 625 } 626 static inline void erofs_fscache_unregister_fs(struct super_block *sb) {} 627 628 static inline 629 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb, 630 char *name, 631 unsigned int flags) 632 { 633 return ERR_PTR(-EOPNOTSUPP); 634 } 635 636 static inline void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache) 637 { 638 } 639 #endif 640 641 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 642 643 #endif /* __EROFS_INTERNAL_H */ 644