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 block_device *bdev; 53 struct dax_device *dax_dev; 54 55 u32 blocks; 56 u32 mapped_blkaddr; 57 }; 58 59 struct erofs_mount_opts { 60 #ifdef CONFIG_EROFS_FS_ZIP 61 /* current strategy of how to use managed cache */ 62 unsigned char cache_strategy; 63 /* strategy of sync decompression (false - auto, true - force on) */ 64 bool readahead_sync_decompress; 65 66 /* threshold for decompression synchronously */ 67 unsigned int max_sync_decompress_pages; 68 #endif 69 unsigned int mount_opt; 70 }; 71 72 struct erofs_dev_context { 73 struct idr tree; 74 struct rw_semaphore rwsem; 75 76 unsigned int extra_devices; 77 }; 78 79 struct erofs_fs_context { 80 struct erofs_mount_opts opt; 81 struct erofs_dev_context *devs; 82 }; 83 84 /* all filesystem-wide lz4 configurations */ 85 struct erofs_sb_lz4_info { 86 /* # of pages needed for EROFS lz4 rolling decompression */ 87 u16 max_distance_pages; 88 /* maximum possible blocks for pclusters in the filesystem */ 89 u16 max_pclusterblks; 90 }; 91 92 struct erofs_sb_info { 93 struct erofs_mount_opts opt; /* options */ 94 #ifdef CONFIG_EROFS_FS_ZIP 95 /* list for all registered superblocks, mainly for shrinker */ 96 struct list_head list; 97 struct mutex umount_mutex; 98 99 /* managed XArray arranged in physical block number */ 100 struct xarray managed_pslots; 101 102 unsigned int shrinker_run_no; 103 u16 available_compr_algs; 104 105 /* pseudo inode to manage cached pages */ 106 struct inode *managed_cache; 107 108 struct erofs_sb_lz4_info lz4; 109 #endif /* CONFIG_EROFS_FS_ZIP */ 110 struct erofs_dev_context *devs; 111 struct dax_device *dax_dev; 112 u64 total_blocks; 113 u32 primarydevice_blocks; 114 115 u32 meta_blkaddr; 116 #ifdef CONFIG_EROFS_FS_XATTR 117 u32 xattr_blkaddr; 118 #endif 119 u16 device_id_mask; /* valid bits of device id to be used */ 120 121 /* inode slot unit size in bit shift */ 122 unsigned char islotbits; 123 124 u32 sb_size; /* total superblock size */ 125 u32 build_time_nsec; 126 u64 build_time; 127 128 /* what we really care is nid, rather than ino.. */ 129 erofs_nid_t root_nid; 130 /* used for statfs, f_files - f_favail */ 131 u64 inos; 132 133 u8 uuid[16]; /* 128-bit uuid for volume */ 134 u8 volume_name[16]; /* volume name */ 135 u32 feature_compat; 136 u32 feature_incompat; 137 }; 138 139 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info) 140 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info) 141 142 /* Mount flags set via mount options or defaults */ 143 #define EROFS_MOUNT_XATTR_USER 0x00000010 144 #define EROFS_MOUNT_POSIX_ACL 0x00000020 145 #define EROFS_MOUNT_DAX_ALWAYS 0x00000040 146 #define EROFS_MOUNT_DAX_NEVER 0x00000080 147 148 #define clear_opt(opt, option) ((opt)->mount_opt &= ~EROFS_MOUNT_##option) 149 #define set_opt(opt, option) ((opt)->mount_opt |= EROFS_MOUNT_##option) 150 #define test_opt(opt, option) ((opt)->mount_opt & EROFS_MOUNT_##option) 151 152 enum { 153 EROFS_ZIP_CACHE_DISABLED, 154 EROFS_ZIP_CACHE_READAHEAD, 155 EROFS_ZIP_CACHE_READAROUND 156 }; 157 158 #ifdef CONFIG_EROFS_FS_ZIP 159 #define EROFS_LOCKED_MAGIC (INT_MIN | 0xE0F510CCL) 160 161 /* basic unit of the workstation of a super_block */ 162 struct erofs_workgroup { 163 /* the workgroup index in the workstation */ 164 pgoff_t index; 165 166 /* overall workgroup reference count */ 167 atomic_t refcount; 168 }; 169 170 #if defined(CONFIG_SMP) 171 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp, 172 int val) 173 { 174 preempt_disable(); 175 if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) { 176 preempt_enable(); 177 return false; 178 } 179 return true; 180 } 181 182 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp, 183 int orig_val) 184 { 185 /* 186 * other observers should notice all modifications 187 * in the freezing period. 188 */ 189 smp_mb(); 190 atomic_set(&grp->refcount, orig_val); 191 preempt_enable(); 192 } 193 194 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp) 195 { 196 return atomic_cond_read_relaxed(&grp->refcount, 197 VAL != EROFS_LOCKED_MAGIC); 198 } 199 #else 200 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp, 201 int val) 202 { 203 preempt_disable(); 204 /* no need to spin on UP platforms, let's just disable preemption. */ 205 if (val != atomic_read(&grp->refcount)) { 206 preempt_enable(); 207 return false; 208 } 209 return true; 210 } 211 212 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp, 213 int orig_val) 214 { 215 preempt_enable(); 216 } 217 218 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp) 219 { 220 int v = atomic_read(&grp->refcount); 221 222 /* workgroup is never freezed on uniprocessor systems */ 223 DBG_BUGON(v == EROFS_LOCKED_MAGIC); 224 return v; 225 } 226 #endif /* !CONFIG_SMP */ 227 #endif /* !CONFIG_EROFS_FS_ZIP */ 228 229 /* we strictly follow PAGE_SIZE and no buffer head yet */ 230 #define LOG_BLOCK_SIZE PAGE_SHIFT 231 232 #undef LOG_SECTORS_PER_BLOCK 233 #define LOG_SECTORS_PER_BLOCK (PAGE_SHIFT - 9) 234 235 #undef SECTORS_PER_BLOCK 236 #define SECTORS_PER_BLOCK (1 << SECTORS_PER_BLOCK) 237 238 #define EROFS_BLKSIZ (1 << LOG_BLOCK_SIZE) 239 240 #if (EROFS_BLKSIZ % 4096 || !EROFS_BLKSIZ) 241 #error erofs cannot be used in this platform 242 #endif 243 244 #define ROOT_NID(sb) ((sb)->root_nid) 245 246 #define erofs_blknr(addr) ((addr) / EROFS_BLKSIZ) 247 #define erofs_blkoff(addr) ((addr) % EROFS_BLKSIZ) 248 #define blknr_to_addr(nr) ((erofs_off_t)(nr) * EROFS_BLKSIZ) 249 250 static inline erofs_off_t iloc(struct erofs_sb_info *sbi, erofs_nid_t nid) 251 { 252 return blknr_to_addr(sbi->meta_blkaddr) + (nid << sbi->islotbits); 253 } 254 255 #define EROFS_FEATURE_FUNCS(name, compat, feature) \ 256 static inline bool erofs_sb_has_##name(struct erofs_sb_info *sbi) \ 257 { \ 258 return sbi->feature_##compat & EROFS_FEATURE_##feature; \ 259 } 260 261 EROFS_FEATURE_FUNCS(lz4_0padding, incompat, INCOMPAT_LZ4_0PADDING) 262 EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS) 263 EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER) 264 EROFS_FEATURE_FUNCS(device_table, incompat, INCOMPAT_DEVICE_TABLE) 265 EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM) 266 267 /* atomic flag definitions */ 268 #define EROFS_I_EA_INITED_BIT 0 269 #define EROFS_I_Z_INITED_BIT 1 270 271 /* bitlock definitions (arranged in reverse order) */ 272 #define EROFS_I_BL_XATTR_BIT (BITS_PER_LONG - 1) 273 #define EROFS_I_BL_Z_BIT (BITS_PER_LONG - 2) 274 275 struct erofs_inode { 276 erofs_nid_t nid; 277 278 /* atomic flags (including bitlocks) */ 279 unsigned long flags; 280 281 unsigned char datalayout; 282 unsigned char inode_isize; 283 unsigned short xattr_isize; 284 285 unsigned int xattr_shared_count; 286 unsigned int *xattr_shared_xattrs; 287 288 union { 289 erofs_blk_t raw_blkaddr; 290 struct { 291 unsigned short chunkformat; 292 unsigned char chunkbits; 293 }; 294 #ifdef CONFIG_EROFS_FS_ZIP 295 struct { 296 unsigned short z_advise; 297 unsigned char z_algorithmtype[2]; 298 unsigned char z_logical_clusterbits; 299 }; 300 #endif /* CONFIG_EROFS_FS_ZIP */ 301 }; 302 /* the corresponding vfs inode */ 303 struct inode vfs_inode; 304 }; 305 306 #define EROFS_I(ptr) \ 307 container_of(ptr, struct erofs_inode, vfs_inode) 308 309 static inline unsigned long erofs_inode_datablocks(struct inode *inode) 310 { 311 /* since i_size cannot be changed */ 312 return DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ); 313 } 314 315 static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit, 316 unsigned int bits) 317 { 318 319 return (value >> bit) & ((1 << bits) - 1); 320 } 321 322 323 static inline unsigned int erofs_inode_version(unsigned int value) 324 { 325 return erofs_bitrange(value, EROFS_I_VERSION_BIT, 326 EROFS_I_VERSION_BITS); 327 } 328 329 static inline unsigned int erofs_inode_datalayout(unsigned int value) 330 { 331 return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT, 332 EROFS_I_DATALAYOUT_BITS); 333 } 334 335 /* 336 * Different from grab_cache_page_nowait(), reclaiming is never triggered 337 * when allocating new pages. 338 */ 339 static inline 340 struct page *erofs_grab_cache_page_nowait(struct address_space *mapping, 341 pgoff_t index) 342 { 343 return pagecache_get_page(mapping, index, 344 FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT, 345 readahead_gfp_mask(mapping) & ~__GFP_RECLAIM); 346 } 347 348 extern const struct super_operations erofs_sops; 349 350 extern const struct address_space_operations erofs_raw_access_aops; 351 extern const struct address_space_operations z_erofs_aops; 352 353 /* 354 * Logical to physical block mapping 355 * 356 * Different with other file systems, it is used for 2 access modes: 357 * 358 * 1) RAW access mode: 359 * 360 * Users pass a valid (m_lblk, m_lofs -- usually 0) pair, 361 * and get the valid m_pblk, m_pofs and the longest m_len(in bytes). 362 * 363 * Note that m_lblk in the RAW access mode refers to the number of 364 * the compressed ondisk block rather than the uncompressed 365 * in-memory block for the compressed file. 366 * 367 * m_pofs equals to m_lofs except for the inline data page. 368 * 369 * 2) Normal access mode: 370 * 371 * If the inode is not compressed, it has no difference with 372 * the RAW access mode. However, if the inode is compressed, 373 * users should pass a valid (m_lblk, m_lofs) pair, and get 374 * the needed m_pblk, m_pofs, m_len to get the compressed data 375 * and the updated m_lblk, m_lofs which indicates the start 376 * of the corresponding uncompressed data in the file. 377 */ 378 enum { 379 BH_Encoded = BH_PrivateStart, 380 BH_FullMapped, 381 }; 382 383 /* Has a disk mapping */ 384 #define EROFS_MAP_MAPPED (1 << BH_Mapped) 385 /* Located in metadata (could be copied from bd_inode) */ 386 #define EROFS_MAP_META (1 << BH_Meta) 387 /* The extent is encoded */ 388 #define EROFS_MAP_ENCODED (1 << BH_Encoded) 389 /* The length of extent is full */ 390 #define EROFS_MAP_FULL_MAPPED (1 << BH_FullMapped) 391 392 struct erofs_map_blocks { 393 erofs_off_t m_pa, m_la; 394 u64 m_plen, m_llen; 395 396 unsigned short m_deviceid; 397 char m_algorithmformat; 398 unsigned int m_flags; 399 400 struct page *mpage; 401 }; 402 403 /* Flags used by erofs_map_blocks_flatmode() */ 404 #define EROFS_GET_BLOCKS_RAW 0x0001 405 /* 406 * Used to get the exact decompressed length, e.g. fiemap (consider lookback 407 * approach instead if possible since it's more metadata lightweight.) 408 */ 409 #define EROFS_GET_BLOCKS_FIEMAP 0x0002 410 /* Used to map the whole extent if non-negligible data is requested for LZMA */ 411 #define EROFS_GET_BLOCKS_READMORE 0x0004 412 413 enum { 414 Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX, 415 Z_EROFS_COMPRESSION_RUNTIME_MAX 416 }; 417 418 /* zmap.c */ 419 extern const struct iomap_ops z_erofs_iomap_report_ops; 420 421 #ifdef CONFIG_EROFS_FS_ZIP 422 int z_erofs_fill_inode(struct inode *inode); 423 int z_erofs_map_blocks_iter(struct inode *inode, 424 struct erofs_map_blocks *map, 425 int flags); 426 #else 427 static inline int z_erofs_fill_inode(struct inode *inode) { return -EOPNOTSUPP; } 428 static inline int z_erofs_map_blocks_iter(struct inode *inode, 429 struct erofs_map_blocks *map, 430 int flags) 431 { 432 return -EOPNOTSUPP; 433 } 434 #endif /* !CONFIG_EROFS_FS_ZIP */ 435 436 struct erofs_map_dev { 437 struct block_device *m_bdev; 438 struct dax_device *m_daxdev; 439 440 erofs_off_t m_pa; 441 unsigned int m_deviceid; 442 }; 443 444 /* data.c */ 445 extern const struct file_operations erofs_file_fops; 446 struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr); 447 int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *dev); 448 int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, 449 u64 start, u64 len); 450 451 /* inode.c */ 452 static inline unsigned long erofs_inode_hash(erofs_nid_t nid) 453 { 454 #if BITS_PER_LONG == 32 455 return (nid >> 32) ^ (nid & 0xffffffff); 456 #else 457 return nid; 458 #endif 459 } 460 461 extern const struct inode_operations erofs_generic_iops; 462 extern const struct inode_operations erofs_symlink_iops; 463 extern const struct inode_operations erofs_fast_symlink_iops; 464 465 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid, bool dir); 466 int erofs_getattr(struct user_namespace *mnt_userns, const struct path *path, 467 struct kstat *stat, u32 request_mask, 468 unsigned int query_flags); 469 470 /* namei.c */ 471 extern const struct inode_operations erofs_dir_iops; 472 473 int erofs_namei(struct inode *dir, struct qstr *name, 474 erofs_nid_t *nid, unsigned int *d_type); 475 476 /* dir.c */ 477 extern const struct file_operations erofs_dir_fops; 478 479 static inline void *erofs_vm_map_ram(struct page **pages, unsigned int count) 480 { 481 int retried = 0; 482 483 while (1) { 484 void *p = vm_map_ram(pages, count, -1); 485 486 /* retry two more times (totally 3 times) */ 487 if (p || ++retried >= 3) 488 return p; 489 vm_unmap_aliases(); 490 } 491 return NULL; 492 } 493 494 /* pcpubuf.c */ 495 void *erofs_get_pcpubuf(unsigned int requiredpages); 496 void erofs_put_pcpubuf(void *ptr); 497 int erofs_pcpubuf_growsize(unsigned int nrpages); 498 void erofs_pcpubuf_init(void); 499 void erofs_pcpubuf_exit(void); 500 501 /* utils.c / zdata.c */ 502 struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp); 503 static inline void erofs_pagepool_add(struct page **pagepool, 504 struct page *page) 505 { 506 set_page_private(page, (unsigned long)*pagepool); 507 *pagepool = page; 508 } 509 void erofs_release_pages(struct page **pagepool); 510 511 #ifdef CONFIG_EROFS_FS_ZIP 512 int erofs_workgroup_put(struct erofs_workgroup *grp); 513 struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb, 514 pgoff_t index); 515 struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb, 516 struct erofs_workgroup *grp); 517 void erofs_workgroup_free_rcu(struct erofs_workgroup *grp); 518 void erofs_shrinker_register(struct super_block *sb); 519 void erofs_shrinker_unregister(struct super_block *sb); 520 int __init erofs_init_shrinker(void); 521 void erofs_exit_shrinker(void); 522 int __init z_erofs_init_zip_subsystem(void); 523 void z_erofs_exit_zip_subsystem(void); 524 int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi, 525 struct erofs_workgroup *egrp); 526 int erofs_try_to_free_cached_page(struct page *page); 527 int z_erofs_load_lz4_config(struct super_block *sb, 528 struct erofs_super_block *dsb, 529 struct z_erofs_lz4_cfgs *lz4, int len); 530 #else 531 static inline void erofs_shrinker_register(struct super_block *sb) {} 532 static inline void erofs_shrinker_unregister(struct super_block *sb) {} 533 static inline int erofs_init_shrinker(void) { return 0; } 534 static inline void erofs_exit_shrinker(void) {} 535 static inline int z_erofs_init_zip_subsystem(void) { return 0; } 536 static inline void z_erofs_exit_zip_subsystem(void) {} 537 static inline int z_erofs_load_lz4_config(struct super_block *sb, 538 struct erofs_super_block *dsb, 539 struct z_erofs_lz4_cfgs *lz4, int len) 540 { 541 if (lz4 || dsb->u1.lz4_max_distance) { 542 erofs_err(sb, "lz4 algorithm isn't enabled"); 543 return -EINVAL; 544 } 545 return 0; 546 } 547 #endif /* !CONFIG_EROFS_FS_ZIP */ 548 549 #ifdef CONFIG_EROFS_FS_ZIP_LZMA 550 int z_erofs_lzma_init(void); 551 void z_erofs_lzma_exit(void); 552 int z_erofs_load_lzma_config(struct super_block *sb, 553 struct erofs_super_block *dsb, 554 struct z_erofs_lzma_cfgs *lzma, int size); 555 #else 556 static inline int z_erofs_lzma_init(void) { return 0; } 557 static inline int z_erofs_lzma_exit(void) { return 0; } 558 static inline int z_erofs_load_lzma_config(struct super_block *sb, 559 struct erofs_super_block *dsb, 560 struct z_erofs_lzma_cfgs *lzma, int size) { 561 if (lzma) { 562 erofs_err(sb, "lzma algorithm isn't enabled"); 563 return -EINVAL; 564 } 565 return 0; 566 } 567 #endif /* !CONFIG_EROFS_FS_ZIP */ 568 569 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 570 571 #endif /* __EROFS_INTERNAL_H */ 572