1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2017-2018 HUAWEI, Inc. 4 * http://www.huawei.com/ 5 * Created by Gao Xiang <gaoxiang25@huawei.com> 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 "erofs_fs.h" 20 21 /* redefine pr_fmt "erofs: " */ 22 #undef pr_fmt 23 #define pr_fmt(fmt) "erofs: " fmt 24 25 __printf(3, 4) void _erofs_err(struct super_block *sb, 26 const char *function, const char *fmt, ...); 27 #define erofs_err(sb, fmt, ...) \ 28 _erofs_err(sb, __func__, fmt "\n", ##__VA_ARGS__) 29 __printf(3, 4) void _erofs_info(struct super_block *sb, 30 const char *function, const char *fmt, ...); 31 #define erofs_info(sb, fmt, ...) \ 32 _erofs_info(sb, __func__, fmt "\n", ##__VA_ARGS__) 33 #ifdef CONFIG_EROFS_FS_DEBUG 34 #define erofs_dbg(x, ...) pr_debug(x "\n", ##__VA_ARGS__) 35 #define DBG_BUGON BUG_ON 36 #else 37 #define erofs_dbg(x, ...) ((void)0) 38 #define DBG_BUGON(x) ((void)(x)) 39 #endif /* !CONFIG_EROFS_FS_DEBUG */ 40 41 /* EROFS_SUPER_MAGIC_V1 to represent the whole file system */ 42 #define EROFS_SUPER_MAGIC EROFS_SUPER_MAGIC_V1 43 44 typedef u64 erofs_nid_t; 45 typedef u64 erofs_off_t; 46 /* data type for filesystem-wide blocks number */ 47 typedef u32 erofs_blk_t; 48 49 struct erofs_sb_info { 50 #ifdef CONFIG_EROFS_FS_ZIP 51 /* list for all registered superblocks, mainly for shrinker */ 52 struct list_head list; 53 struct mutex umount_mutex; 54 55 /* managed XArray arranged in physical block number */ 56 struct xarray managed_pslots; 57 58 /* threshold for decompression synchronously */ 59 unsigned int max_sync_decompress_pages; 60 61 unsigned int shrinker_run_no; 62 63 /* current strategy of how to use managed cache */ 64 unsigned char cache_strategy; 65 66 /* pseudo inode to manage cached pages */ 67 struct inode *managed_cache; 68 #endif /* CONFIG_EROFS_FS_ZIP */ 69 u32 blocks; 70 u32 meta_blkaddr; 71 #ifdef CONFIG_EROFS_FS_XATTR 72 u32 xattr_blkaddr; 73 #endif 74 75 /* inode slot unit size in bit shift */ 76 unsigned char islotbits; 77 78 u32 build_time_nsec; 79 u64 build_time; 80 81 /* what we really care is nid, rather than ino.. */ 82 erofs_nid_t root_nid; 83 /* used for statfs, f_files - f_favail */ 84 u64 inos; 85 86 u8 uuid[16]; /* 128-bit uuid for volume */ 87 u8 volume_name[16]; /* volume name */ 88 u32 feature_compat; 89 u32 feature_incompat; 90 91 unsigned int mount_opt; 92 }; 93 94 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info) 95 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info) 96 97 /* Mount flags set via mount options or defaults */ 98 #define EROFS_MOUNT_XATTR_USER 0x00000010 99 #define EROFS_MOUNT_POSIX_ACL 0x00000020 100 101 #define clear_opt(sbi, option) ((sbi)->mount_opt &= ~EROFS_MOUNT_##option) 102 #define set_opt(sbi, option) ((sbi)->mount_opt |= EROFS_MOUNT_##option) 103 #define test_opt(sbi, option) ((sbi)->mount_opt & EROFS_MOUNT_##option) 104 105 #ifdef CONFIG_EROFS_FS_ZIP 106 enum { 107 EROFS_ZIP_CACHE_DISABLED, 108 EROFS_ZIP_CACHE_READAHEAD, 109 EROFS_ZIP_CACHE_READAROUND 110 }; 111 112 #define EROFS_LOCKED_MAGIC (INT_MIN | 0xE0F510CCL) 113 114 /* basic unit of the workstation of a super_block */ 115 struct erofs_workgroup { 116 /* the workgroup index in the workstation */ 117 pgoff_t index; 118 119 /* overall workgroup reference count */ 120 atomic_t refcount; 121 }; 122 123 #if defined(CONFIG_SMP) 124 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp, 125 int val) 126 { 127 preempt_disable(); 128 if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) { 129 preempt_enable(); 130 return false; 131 } 132 return true; 133 } 134 135 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp, 136 int orig_val) 137 { 138 /* 139 * other observers should notice all modifications 140 * in the freezing period. 141 */ 142 smp_mb(); 143 atomic_set(&grp->refcount, orig_val); 144 preempt_enable(); 145 } 146 147 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp) 148 { 149 return atomic_cond_read_relaxed(&grp->refcount, 150 VAL != EROFS_LOCKED_MAGIC); 151 } 152 #else 153 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp, 154 int val) 155 { 156 preempt_disable(); 157 /* no need to spin on UP platforms, let's just disable preemption. */ 158 if (val != atomic_read(&grp->refcount)) { 159 preempt_enable(); 160 return false; 161 } 162 return true; 163 } 164 165 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp, 166 int orig_val) 167 { 168 preempt_enable(); 169 } 170 171 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp) 172 { 173 int v = atomic_read(&grp->refcount); 174 175 /* workgroup is never freezed on uniprocessor systems */ 176 DBG_BUGON(v == EROFS_LOCKED_MAGIC); 177 return v; 178 } 179 #endif /* !CONFIG_SMP */ 180 181 /* hard limit of pages per compressed cluster */ 182 #define Z_EROFS_CLUSTER_MAX_PAGES (CONFIG_EROFS_FS_CLUSTER_PAGE_LIMIT) 183 #define EROFS_PCPUBUF_NR_PAGES Z_EROFS_CLUSTER_MAX_PAGES 184 #else 185 #define EROFS_PCPUBUF_NR_PAGES 0 186 #endif /* !CONFIG_EROFS_FS_ZIP */ 187 188 /* we strictly follow PAGE_SIZE and no buffer head yet */ 189 #define LOG_BLOCK_SIZE PAGE_SHIFT 190 191 #undef LOG_SECTORS_PER_BLOCK 192 #define LOG_SECTORS_PER_BLOCK (PAGE_SHIFT - 9) 193 194 #undef SECTORS_PER_BLOCK 195 #define SECTORS_PER_BLOCK (1 << SECTORS_PER_BLOCK) 196 197 #define EROFS_BLKSIZ (1 << LOG_BLOCK_SIZE) 198 199 #if (EROFS_BLKSIZ % 4096 || !EROFS_BLKSIZ) 200 #error erofs cannot be used in this platform 201 #endif 202 203 #define ROOT_NID(sb) ((sb)->root_nid) 204 205 #define erofs_blknr(addr) ((addr) / EROFS_BLKSIZ) 206 #define erofs_blkoff(addr) ((addr) % EROFS_BLKSIZ) 207 #define blknr_to_addr(nr) ((erofs_off_t)(nr) * EROFS_BLKSIZ) 208 209 static inline erofs_off_t iloc(struct erofs_sb_info *sbi, erofs_nid_t nid) 210 { 211 return blknr_to_addr(sbi->meta_blkaddr) + (nid << sbi->islotbits); 212 } 213 214 /* atomic flag definitions */ 215 #define EROFS_I_EA_INITED_BIT 0 216 #define EROFS_I_Z_INITED_BIT 1 217 218 /* bitlock definitions (arranged in reverse order) */ 219 #define EROFS_I_BL_XATTR_BIT (BITS_PER_LONG - 1) 220 #define EROFS_I_BL_Z_BIT (BITS_PER_LONG - 2) 221 222 struct erofs_inode { 223 erofs_nid_t nid; 224 225 /* atomic flags (including bitlocks) */ 226 unsigned long flags; 227 228 unsigned char datalayout; 229 unsigned char inode_isize; 230 unsigned short xattr_isize; 231 232 unsigned int xattr_shared_count; 233 unsigned int *xattr_shared_xattrs; 234 235 union { 236 erofs_blk_t raw_blkaddr; 237 #ifdef CONFIG_EROFS_FS_ZIP 238 struct { 239 unsigned short z_advise; 240 unsigned char z_algorithmtype[2]; 241 unsigned char z_logical_clusterbits; 242 unsigned char z_physical_clusterbits[2]; 243 }; 244 #endif /* CONFIG_EROFS_FS_ZIP */ 245 }; 246 /* the corresponding vfs inode */ 247 struct inode vfs_inode; 248 }; 249 250 #define EROFS_I(ptr) \ 251 container_of(ptr, struct erofs_inode, vfs_inode) 252 253 static inline unsigned long erofs_inode_datablocks(struct inode *inode) 254 { 255 /* since i_size cannot be changed */ 256 return DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ); 257 } 258 259 static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit, 260 unsigned int bits) 261 { 262 263 return (value >> bit) & ((1 << bits) - 1); 264 } 265 266 267 static inline unsigned int erofs_inode_version(unsigned int value) 268 { 269 return erofs_bitrange(value, EROFS_I_VERSION_BIT, 270 EROFS_I_VERSION_BITS); 271 } 272 273 static inline unsigned int erofs_inode_datalayout(unsigned int value) 274 { 275 return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT, 276 EROFS_I_DATALAYOUT_BITS); 277 } 278 279 extern const struct super_operations erofs_sops; 280 281 extern const struct address_space_operations erofs_raw_access_aops; 282 extern const struct address_space_operations z_erofs_aops; 283 284 /* 285 * Logical to physical block mapping, used by erofs_map_blocks() 286 * 287 * Different with other file systems, it is used for 2 access modes: 288 * 289 * 1) RAW access mode: 290 * 291 * Users pass a valid (m_lblk, m_lofs -- usually 0) pair, 292 * and get the valid m_pblk, m_pofs and the longest m_len(in bytes). 293 * 294 * Note that m_lblk in the RAW access mode refers to the number of 295 * the compressed ondisk block rather than the uncompressed 296 * in-memory block for the compressed file. 297 * 298 * m_pofs equals to m_lofs except for the inline data page. 299 * 300 * 2) Normal access mode: 301 * 302 * If the inode is not compressed, it has no difference with 303 * the RAW access mode. However, if the inode is compressed, 304 * users should pass a valid (m_lblk, m_lofs) pair, and get 305 * the needed m_pblk, m_pofs, m_len to get the compressed data 306 * and the updated m_lblk, m_lofs which indicates the start 307 * of the corresponding uncompressed data in the file. 308 */ 309 enum { 310 BH_Zipped = BH_PrivateStart, 311 BH_FullMapped, 312 }; 313 314 /* Has a disk mapping */ 315 #define EROFS_MAP_MAPPED (1 << BH_Mapped) 316 /* Located in metadata (could be copied from bd_inode) */ 317 #define EROFS_MAP_META (1 << BH_Meta) 318 /* The extent has been compressed */ 319 #define EROFS_MAP_ZIPPED (1 << BH_Zipped) 320 /* The length of extent is full */ 321 #define EROFS_MAP_FULL_MAPPED (1 << BH_FullMapped) 322 323 struct erofs_map_blocks { 324 erofs_off_t m_pa, m_la; 325 u64 m_plen, m_llen; 326 327 unsigned int m_flags; 328 329 struct page *mpage; 330 }; 331 332 /* Flags used by erofs_map_blocks() */ 333 #define EROFS_GET_BLOCKS_RAW 0x0001 334 335 /* zmap.c */ 336 #ifdef CONFIG_EROFS_FS_ZIP 337 int z_erofs_fill_inode(struct inode *inode); 338 int z_erofs_map_blocks_iter(struct inode *inode, 339 struct erofs_map_blocks *map, 340 int flags); 341 #else 342 static inline int z_erofs_fill_inode(struct inode *inode) { return -EOPNOTSUPP; } 343 static inline int z_erofs_map_blocks_iter(struct inode *inode, 344 struct erofs_map_blocks *map, 345 int flags) 346 { 347 return -EOPNOTSUPP; 348 } 349 #endif /* !CONFIG_EROFS_FS_ZIP */ 350 351 /* data.c */ 352 struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr); 353 354 int erofs_map_blocks(struct inode *, struct erofs_map_blocks *, int); 355 356 /* inode.c */ 357 static inline unsigned long erofs_inode_hash(erofs_nid_t nid) 358 { 359 #if BITS_PER_LONG == 32 360 return (nid >> 32) ^ (nid & 0xffffffff); 361 #else 362 return nid; 363 #endif 364 } 365 366 extern const struct inode_operations erofs_generic_iops; 367 extern const struct inode_operations erofs_symlink_iops; 368 extern const struct inode_operations erofs_fast_symlink_iops; 369 370 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid, bool dir); 371 int erofs_getattr(const struct path *path, struct kstat *stat, 372 u32 request_mask, unsigned int query_flags); 373 374 /* namei.c */ 375 extern const struct inode_operations erofs_dir_iops; 376 377 int erofs_namei(struct inode *dir, struct qstr *name, 378 erofs_nid_t *nid, unsigned int *d_type); 379 380 /* dir.c */ 381 extern const struct file_operations erofs_dir_fops; 382 383 /* utils.c / zdata.c */ 384 struct page *erofs_allocpage(struct list_head *pool, gfp_t gfp); 385 386 #if (EROFS_PCPUBUF_NR_PAGES > 0) 387 void *erofs_get_pcpubuf(unsigned int pagenr); 388 #define erofs_put_pcpubuf(buf) do { \ 389 (void)&(buf); \ 390 preempt_enable(); \ 391 } while (0) 392 #else 393 static inline void *erofs_get_pcpubuf(unsigned int pagenr) 394 { 395 return ERR_PTR(-EOPNOTSUPP); 396 } 397 398 #define erofs_put_pcpubuf(buf) do {} while (0) 399 #endif 400 401 #ifdef CONFIG_EROFS_FS_ZIP 402 int erofs_workgroup_put(struct erofs_workgroup *grp); 403 struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb, 404 pgoff_t index); 405 struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb, 406 struct erofs_workgroup *grp); 407 void erofs_workgroup_free_rcu(struct erofs_workgroup *grp); 408 void erofs_shrinker_register(struct super_block *sb); 409 void erofs_shrinker_unregister(struct super_block *sb); 410 int __init erofs_init_shrinker(void); 411 void erofs_exit_shrinker(void); 412 int __init z_erofs_init_zip_subsystem(void); 413 void z_erofs_exit_zip_subsystem(void); 414 int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi, 415 struct erofs_workgroup *egrp); 416 int erofs_try_to_free_cached_page(struct address_space *mapping, 417 struct page *page); 418 #else 419 static inline void erofs_shrinker_register(struct super_block *sb) {} 420 static inline void erofs_shrinker_unregister(struct super_block *sb) {} 421 static inline int erofs_init_shrinker(void) { return 0; } 422 static inline void erofs_exit_shrinker(void) {} 423 static inline int z_erofs_init_zip_subsystem(void) { return 0; } 424 static inline void z_erofs_exit_zip_subsystem(void) {} 425 #endif /* !CONFIG_EROFS_FS_ZIP */ 426 427 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 428 429 #endif /* __EROFS_INTERNAL_H */ 430 431