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 /* the dedicated workstation for compression */ 56 struct radix_tree_root workstn_tree; 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_incompat; 89 90 unsigned int mount_opt; 91 }; 92 93 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info) 94 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info) 95 96 /* Mount flags set via mount options or defaults */ 97 #define EROFS_MOUNT_XATTR_USER 0x00000010 98 #define EROFS_MOUNT_POSIX_ACL 0x00000020 99 100 #define clear_opt(sbi, option) ((sbi)->mount_opt &= ~EROFS_MOUNT_##option) 101 #define set_opt(sbi, option) ((sbi)->mount_opt |= EROFS_MOUNT_##option) 102 #define test_opt(sbi, option) ((sbi)->mount_opt & EROFS_MOUNT_##option) 103 104 #ifdef CONFIG_EROFS_FS_ZIP 105 enum { 106 EROFS_ZIP_CACHE_DISABLED, 107 EROFS_ZIP_CACHE_READAHEAD, 108 EROFS_ZIP_CACHE_READAROUND 109 }; 110 111 #define EROFS_LOCKED_MAGIC (INT_MIN | 0xE0F510CCL) 112 113 /* basic unit of the workstation of a super_block */ 114 struct erofs_workgroup { 115 /* the workgroup index in the workstation */ 116 pgoff_t index; 117 118 /* overall workgroup reference count */ 119 atomic_t refcount; 120 }; 121 122 #if defined(CONFIG_SMP) 123 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp, 124 int val) 125 { 126 preempt_disable(); 127 if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) { 128 preempt_enable(); 129 return false; 130 } 131 return true; 132 } 133 134 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp, 135 int orig_val) 136 { 137 /* 138 * other observers should notice all modifications 139 * in the freezing period. 140 */ 141 smp_mb(); 142 atomic_set(&grp->refcount, orig_val); 143 preempt_enable(); 144 } 145 146 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp) 147 { 148 return atomic_cond_read_relaxed(&grp->refcount, 149 VAL != EROFS_LOCKED_MAGIC); 150 } 151 #else 152 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp, 153 int val) 154 { 155 preempt_disable(); 156 /* no need to spin on UP platforms, let's just disable preemption. */ 157 if (val != atomic_read(&grp->refcount)) { 158 preempt_enable(); 159 return false; 160 } 161 return true; 162 } 163 164 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp, 165 int orig_val) 166 { 167 preempt_enable(); 168 } 169 170 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp) 171 { 172 int v = atomic_read(&grp->refcount); 173 174 /* workgroup is never freezed on uniprocessor systems */ 175 DBG_BUGON(v == EROFS_LOCKED_MAGIC); 176 return v; 177 } 178 #endif /* !CONFIG_SMP */ 179 180 /* hard limit of pages per compressed cluster */ 181 #define Z_EROFS_CLUSTER_MAX_PAGES (CONFIG_EROFS_FS_CLUSTER_PAGE_LIMIT) 182 #define EROFS_PCPUBUF_NR_PAGES Z_EROFS_CLUSTER_MAX_PAGES 183 #else 184 #define EROFS_PCPUBUF_NR_PAGES 0 185 #endif /* !CONFIG_EROFS_FS_ZIP */ 186 187 /* we strictly follow PAGE_SIZE and no buffer head yet */ 188 #define LOG_BLOCK_SIZE PAGE_SHIFT 189 190 #undef LOG_SECTORS_PER_BLOCK 191 #define LOG_SECTORS_PER_BLOCK (PAGE_SHIFT - 9) 192 193 #undef SECTORS_PER_BLOCK 194 #define SECTORS_PER_BLOCK (1 << SECTORS_PER_BLOCK) 195 196 #define EROFS_BLKSIZ (1 << LOG_BLOCK_SIZE) 197 198 #if (EROFS_BLKSIZ % 4096 || !EROFS_BLKSIZ) 199 #error erofs cannot be used in this platform 200 #endif 201 202 #define ROOT_NID(sb) ((sb)->root_nid) 203 204 #define erofs_blknr(addr) ((addr) / EROFS_BLKSIZ) 205 #define erofs_blkoff(addr) ((addr) % EROFS_BLKSIZ) 206 #define blknr_to_addr(nr) ((erofs_off_t)(nr) * EROFS_BLKSIZ) 207 208 static inline erofs_off_t iloc(struct erofs_sb_info *sbi, erofs_nid_t nid) 209 { 210 return blknr_to_addr(sbi->meta_blkaddr) + (nid << sbi->islotbits); 211 } 212 213 /* atomic flag definitions */ 214 #define EROFS_I_EA_INITED_BIT 0 215 #define EROFS_I_Z_INITED_BIT 1 216 217 /* bitlock definitions (arranged in reverse order) */ 218 #define EROFS_I_BL_XATTR_BIT (BITS_PER_LONG - 1) 219 #define EROFS_I_BL_Z_BIT (BITS_PER_LONG - 2) 220 221 struct erofs_inode { 222 erofs_nid_t nid; 223 224 /* atomic flags (including bitlocks) */ 225 unsigned long flags; 226 227 unsigned char datalayout; 228 unsigned char inode_isize; 229 unsigned short xattr_isize; 230 231 unsigned int xattr_shared_count; 232 unsigned int *xattr_shared_xattrs; 233 234 union { 235 erofs_blk_t raw_blkaddr; 236 #ifdef CONFIG_EROFS_FS_ZIP 237 struct { 238 unsigned short z_advise; 239 unsigned char z_algorithmtype[2]; 240 unsigned char z_logical_clusterbits; 241 unsigned char z_physical_clusterbits[2]; 242 }; 243 #endif /* CONFIG_EROFS_FS_ZIP */ 244 }; 245 /* the corresponding vfs inode */ 246 struct inode vfs_inode; 247 }; 248 249 #define EROFS_I(ptr) \ 250 container_of(ptr, struct erofs_inode, vfs_inode) 251 252 static inline unsigned long erofs_inode_datablocks(struct inode *inode) 253 { 254 /* since i_size cannot be changed */ 255 return DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ); 256 } 257 258 static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit, 259 unsigned int bits) 260 { 261 262 return (value >> bit) & ((1 << bits) - 1); 263 } 264 265 266 static inline unsigned int erofs_inode_version(unsigned int value) 267 { 268 return erofs_bitrange(value, EROFS_I_VERSION_BIT, 269 EROFS_I_VERSION_BITS); 270 } 271 272 static inline unsigned int erofs_inode_datalayout(unsigned int value) 273 { 274 return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT, 275 EROFS_I_DATALAYOUT_BITS); 276 } 277 278 extern const struct super_operations erofs_sops; 279 280 extern const struct address_space_operations erofs_raw_access_aops; 281 #ifdef CONFIG_EROFS_FS_ZIP 282 extern const struct address_space_operations z_erofs_vle_normalaccess_aops; 283 #endif 284 285 /* 286 * Logical to physical block mapping, used by erofs_map_blocks() 287 * 288 * Different with other file systems, it is used for 2 access modes: 289 * 290 * 1) RAW access mode: 291 * 292 * Users pass a valid (m_lblk, m_lofs -- usually 0) pair, 293 * and get the valid m_pblk, m_pofs and the longest m_len(in bytes). 294 * 295 * Note that m_lblk in the RAW access mode refers to the number of 296 * the compressed ondisk block rather than the uncompressed 297 * in-memory block for the compressed file. 298 * 299 * m_pofs equals to m_lofs except for the inline data page. 300 * 301 * 2) Normal access mode: 302 * 303 * If the inode is not compressed, it has no difference with 304 * the RAW access mode. However, if the inode is compressed, 305 * users should pass a valid (m_lblk, m_lofs) pair, and get 306 * the needed m_pblk, m_pofs, m_len to get the compressed data 307 * and the updated m_lblk, m_lofs which indicates the start 308 * of the corresponding uncompressed data in the file. 309 */ 310 enum { 311 BH_Zipped = BH_PrivateStart, 312 BH_FullMapped, 313 }; 314 315 /* Has a disk mapping */ 316 #define EROFS_MAP_MAPPED (1 << BH_Mapped) 317 /* Located in metadata (could be copied from bd_inode) */ 318 #define EROFS_MAP_META (1 << BH_Meta) 319 /* The extent has been compressed */ 320 #define EROFS_MAP_ZIPPED (1 << BH_Zipped) 321 /* The length of extent is full */ 322 #define EROFS_MAP_FULL_MAPPED (1 << BH_FullMapped) 323 324 struct erofs_map_blocks { 325 erofs_off_t m_pa, m_la; 326 u64 m_plen, m_llen; 327 328 unsigned int m_flags; 329 330 struct page *mpage; 331 }; 332 333 /* Flags used by erofs_map_blocks() */ 334 #define EROFS_GET_BLOCKS_RAW 0x0001 335 336 /* zmap.c */ 337 #ifdef CONFIG_EROFS_FS_ZIP 338 int z_erofs_fill_inode(struct inode *inode); 339 int z_erofs_map_blocks_iter(struct inode *inode, 340 struct erofs_map_blocks *map, 341 int flags); 342 #else 343 static inline int z_erofs_fill_inode(struct inode *inode) { return -EOPNOTSUPP; } 344 static inline int z_erofs_map_blocks_iter(struct inode *inode, 345 struct erofs_map_blocks *map, 346 int flags) 347 { 348 return -EOPNOTSUPP; 349 } 350 #endif /* !CONFIG_EROFS_FS_ZIP */ 351 352 /* data.c */ 353 struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr); 354 355 int erofs_map_blocks(struct inode *, struct erofs_map_blocks *, int); 356 357 /* inode.c */ 358 static inline unsigned long erofs_inode_hash(erofs_nid_t nid) 359 { 360 #if BITS_PER_LONG == 32 361 return (nid >> 32) ^ (nid & 0xffffffff); 362 #else 363 return nid; 364 #endif 365 } 366 367 extern const struct inode_operations erofs_generic_iops; 368 extern const struct inode_operations erofs_symlink_iops; 369 extern const struct inode_operations erofs_fast_symlink_iops; 370 371 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid, bool dir); 372 int erofs_getattr(const struct path *path, struct kstat *stat, 373 u32 request_mask, unsigned int query_flags); 374 375 /* namei.c */ 376 extern const struct inode_operations erofs_dir_iops; 377 378 int erofs_namei(struct inode *dir, struct qstr *name, 379 erofs_nid_t *nid, unsigned int *d_type); 380 381 /* dir.c */ 382 extern const struct file_operations erofs_dir_fops; 383 384 /* utils.c / zdata.c */ 385 struct page *erofs_allocpage(struct list_head *pool, gfp_t gfp, bool nofail); 386 387 #if (EROFS_PCPUBUF_NR_PAGES > 0) 388 void *erofs_get_pcpubuf(unsigned int pagenr); 389 #define erofs_put_pcpubuf(buf) do { \ 390 (void)&(buf); \ 391 preempt_enable(); \ 392 } while (0) 393 #else 394 static inline void *erofs_get_pcpubuf(unsigned int pagenr) 395 { 396 return ERR_PTR(-EOPNOTSUPP); 397 } 398 399 #define erofs_put_pcpubuf(buf) do {} while (0) 400 #endif 401 402 #ifdef CONFIG_EROFS_FS_ZIP 403 int erofs_workgroup_put(struct erofs_workgroup *grp); 404 struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb, 405 pgoff_t index, bool *tag); 406 int erofs_register_workgroup(struct super_block *sb, 407 struct erofs_workgroup *grp, bool tag); 408 void erofs_workgroup_free_rcu(struct erofs_workgroup *grp); 409 void erofs_shrinker_register(struct super_block *sb); 410 void erofs_shrinker_unregister(struct super_block *sb); 411 int __init erofs_init_shrinker(void); 412 void erofs_exit_shrinker(void); 413 int __init z_erofs_init_zip_subsystem(void); 414 void z_erofs_exit_zip_subsystem(void); 415 int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi, 416 struct erofs_workgroup *egrp); 417 int erofs_try_to_free_cached_page(struct address_space *mapping, 418 struct page *page); 419 #else 420 static inline void erofs_shrinker_register(struct super_block *sb) {} 421 static inline void erofs_shrinker_unregister(struct super_block *sb) {} 422 static inline int erofs_init_shrinker(void) { return 0; } 423 static inline void erofs_exit_shrinker(void) {} 424 static inline int z_erofs_init_zip_subsystem(void) { return 0; } 425 static inline void z_erofs_exit_zip_subsystem(void) {} 426 #endif /* !CONFIG_EROFS_FS_ZIP */ 427 428 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 429 430 #endif /* __EROFS_INTERNAL_H */ 431 432