1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Copyright (C) 2017-2018 HUAWEI, Inc.
4 * https://www.huawei.com/
6 #ifndef __EROFS_INTERNAL_H
7 #define __EROFS_INTERNAL_H
10 #include <linux/dcache.h>
12 #include <linux/pagemap.h>
13 #include <linux/bio.h>
14 #include <linux/buffer_head.h>
15 #include <linux/magic.h>
16 #include <linux/slab.h>
17 #include <linux/vmalloc.h>
20 /* redefine pr_fmt "erofs: " */
22 #define pr_fmt(fmt) "erofs: " fmt
24 __printf(3, 4) void _erofs_err(struct super_block *sb,
25 const char *function, const char *fmt, ...);
26 #define erofs_err(sb, fmt, ...) \
27 _erofs_err(sb, __func__, fmt "\n", ##__VA_ARGS__)
28 __printf(3, 4) void _erofs_info(struct super_block *sb,
29 const char *function, const char *fmt, ...);
30 #define erofs_info(sb, fmt, ...) \
31 _erofs_info(sb, __func__, fmt "\n", ##__VA_ARGS__)
32 #ifdef CONFIG_EROFS_FS_DEBUG
33 #define erofs_dbg(x, ...) pr_debug(x "\n", ##__VA_ARGS__)
34 #define DBG_BUGON BUG_ON
36 #define erofs_dbg(x, ...) ((void)0)
37 #define DBG_BUGON(x) ((void)(x))
38 #endif /* !CONFIG_EROFS_FS_DEBUG */
40 /* EROFS_SUPER_MAGIC_V1 to represent the whole file system */
41 #define EROFS_SUPER_MAGIC EROFS_SUPER_MAGIC_V1
43 typedef u64 erofs_nid_t;
44 typedef u64 erofs_off_t;
45 /* data type for filesystem-wide blocks number */
46 typedef u32 erofs_blk_t;
48 struct erofs_fs_context {
49 #ifdef CONFIG_EROFS_FS_ZIP
50 /* current strategy of how to use managed cache */
51 unsigned char cache_strategy;
52 /* strategy of sync decompression (false - auto, true - force on) */
53 bool readahead_sync_decompress;
55 /* threshold for decompression synchronously */
56 unsigned int max_sync_decompress_pages;
58 unsigned int mount_opt;
61 /* all filesystem-wide lz4 configurations */
62 struct erofs_sb_lz4_info {
63 /* # of pages needed for EROFS lz4 rolling decompression */
64 u16 max_distance_pages;
65 /* maximum possible blocks for pclusters in the filesystem */
69 struct erofs_sb_info {
70 #ifdef CONFIG_EROFS_FS_ZIP
71 /* list for all registered superblocks, mainly for shrinker */
72 struct list_head list;
73 struct mutex umount_mutex;
75 /* managed XArray arranged in physical block number */
76 struct xarray managed_pslots;
78 unsigned int shrinker_run_no;
79 u16 available_compr_algs;
81 /* pseudo inode to manage cached pages */
82 struct inode *managed_cache;
84 struct erofs_sb_lz4_info lz4;
85 #endif /* CONFIG_EROFS_FS_ZIP */
88 #ifdef CONFIG_EROFS_FS_XATTR
92 /* inode slot unit size in bit shift */
93 unsigned char islotbits;
95 u32 sb_size; /* total superblock size */
99 /* what we really care is nid, rather than ino.. */
100 erofs_nid_t root_nid;
101 /* used for statfs, f_files - f_favail */
104 u8 uuid[16]; /* 128-bit uuid for volume */
105 u8 volume_name[16]; /* volume name */
107 u32 feature_incompat;
109 struct erofs_fs_context ctx; /* options */
112 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
113 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)
115 /* Mount flags set via mount options or defaults */
116 #define EROFS_MOUNT_XATTR_USER 0x00000010
117 #define EROFS_MOUNT_POSIX_ACL 0x00000020
119 #define clear_opt(ctx, option) ((ctx)->mount_opt &= ~EROFS_MOUNT_##option)
120 #define set_opt(ctx, option) ((ctx)->mount_opt |= EROFS_MOUNT_##option)
121 #define test_opt(ctx, option) ((ctx)->mount_opt & EROFS_MOUNT_##option)
124 EROFS_ZIP_CACHE_DISABLED,
125 EROFS_ZIP_CACHE_READAHEAD,
126 EROFS_ZIP_CACHE_READAROUND
129 #ifdef CONFIG_EROFS_FS_ZIP
130 #define EROFS_LOCKED_MAGIC (INT_MIN | 0xE0F510CCL)
132 /* basic unit of the workstation of a super_block */
133 struct erofs_workgroup {
134 /* the workgroup index in the workstation */
137 /* overall workgroup reference count */
141 #if defined(CONFIG_SMP)
142 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
146 if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) {
153 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
157 * other observers should notice all modifications
158 * in the freezing period.
161 atomic_set(&grp->refcount, orig_val);
165 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
167 return atomic_cond_read_relaxed(&grp->refcount,
168 VAL != EROFS_LOCKED_MAGIC);
171 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
175 /* no need to spin on UP platforms, let's just disable preemption. */
176 if (val != atomic_read(&grp->refcount)) {
183 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
189 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
191 int v = atomic_read(&grp->refcount);
193 /* workgroup is never freezed on uniprocessor systems */
194 DBG_BUGON(v == EROFS_LOCKED_MAGIC);
197 #endif /* !CONFIG_SMP */
198 #endif /* !CONFIG_EROFS_FS_ZIP */
200 /* we strictly follow PAGE_SIZE and no buffer head yet */
201 #define LOG_BLOCK_SIZE PAGE_SHIFT
203 #undef LOG_SECTORS_PER_BLOCK
204 #define LOG_SECTORS_PER_BLOCK (PAGE_SHIFT - 9)
206 #undef SECTORS_PER_BLOCK
207 #define SECTORS_PER_BLOCK (1 << SECTORS_PER_BLOCK)
209 #define EROFS_BLKSIZ (1 << LOG_BLOCK_SIZE)
211 #if (EROFS_BLKSIZ % 4096 || !EROFS_BLKSIZ)
212 #error erofs cannot be used in this platform
215 #define ROOT_NID(sb) ((sb)->root_nid)
217 #define erofs_blknr(addr) ((addr) / EROFS_BLKSIZ)
218 #define erofs_blkoff(addr) ((addr) % EROFS_BLKSIZ)
219 #define blknr_to_addr(nr) ((erofs_off_t)(nr) * EROFS_BLKSIZ)
221 static inline erofs_off_t iloc(struct erofs_sb_info *sbi, erofs_nid_t nid)
223 return blknr_to_addr(sbi->meta_blkaddr) + (nid << sbi->islotbits);
226 #define EROFS_FEATURE_FUNCS(name, compat, feature) \
227 static inline bool erofs_sb_has_##name(struct erofs_sb_info *sbi) \
229 return sbi->feature_##compat & EROFS_FEATURE_##feature; \
232 EROFS_FEATURE_FUNCS(lz4_0padding, incompat, INCOMPAT_LZ4_0PADDING)
233 EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS)
234 EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER)
235 EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
237 /* atomic flag definitions */
238 #define EROFS_I_EA_INITED_BIT 0
239 #define EROFS_I_Z_INITED_BIT 1
241 /* bitlock definitions (arranged in reverse order) */
242 #define EROFS_I_BL_XATTR_BIT (BITS_PER_LONG - 1)
243 #define EROFS_I_BL_Z_BIT (BITS_PER_LONG - 2)
248 /* atomic flags (including bitlocks) */
251 unsigned char datalayout;
252 unsigned char inode_isize;
253 unsigned short xattr_isize;
255 unsigned int xattr_shared_count;
256 unsigned int *xattr_shared_xattrs;
259 erofs_blk_t raw_blkaddr;
260 #ifdef CONFIG_EROFS_FS_ZIP
262 unsigned short z_advise;
263 unsigned char z_algorithmtype[2];
264 unsigned char z_logical_clusterbits;
266 #endif /* CONFIG_EROFS_FS_ZIP */
268 /* the corresponding vfs inode */
269 struct inode vfs_inode;
272 #define EROFS_I(ptr) \
273 container_of(ptr, struct erofs_inode, vfs_inode)
275 static inline unsigned long erofs_inode_datablocks(struct inode *inode)
277 /* since i_size cannot be changed */
278 return DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ);
281 static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit,
285 return (value >> bit) & ((1 << bits) - 1);
289 static inline unsigned int erofs_inode_version(unsigned int value)
291 return erofs_bitrange(value, EROFS_I_VERSION_BIT,
292 EROFS_I_VERSION_BITS);
295 static inline unsigned int erofs_inode_datalayout(unsigned int value)
297 return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT,
298 EROFS_I_DATALAYOUT_BITS);
301 extern const struct super_operations erofs_sops;
303 extern const struct address_space_operations erofs_raw_access_aops;
304 extern const struct address_space_operations z_erofs_aops;
307 * Logical to physical block mapping
309 * Different with other file systems, it is used for 2 access modes:
311 * 1) RAW access mode:
313 * Users pass a valid (m_lblk, m_lofs -- usually 0) pair,
314 * and get the valid m_pblk, m_pofs and the longest m_len(in bytes).
316 * Note that m_lblk in the RAW access mode refers to the number of
317 * the compressed ondisk block rather than the uncompressed
318 * in-memory block for the compressed file.
320 * m_pofs equals to m_lofs except for the inline data page.
322 * 2) Normal access mode:
324 * If the inode is not compressed, it has no difference with
325 * the RAW access mode. However, if the inode is compressed,
326 * users should pass a valid (m_lblk, m_lofs) pair, and get
327 * the needed m_pblk, m_pofs, m_len to get the compressed data
328 * and the updated m_lblk, m_lofs which indicates the start
329 * of the corresponding uncompressed data in the file.
332 BH_Zipped = BH_PrivateStart,
336 /* Has a disk mapping */
337 #define EROFS_MAP_MAPPED (1 << BH_Mapped)
338 /* Located in metadata (could be copied from bd_inode) */
339 #define EROFS_MAP_META (1 << BH_Meta)
340 /* The extent has been compressed */
341 #define EROFS_MAP_ZIPPED (1 << BH_Zipped)
342 /* The length of extent is full */
343 #define EROFS_MAP_FULL_MAPPED (1 << BH_FullMapped)
345 struct erofs_map_blocks {
346 erofs_off_t m_pa, m_la;
349 unsigned int m_flags;
354 /* Flags used by erofs_map_blocks_flatmode() */
355 #define EROFS_GET_BLOCKS_RAW 0x0001
358 #ifdef CONFIG_EROFS_FS_ZIP
359 int z_erofs_fill_inode(struct inode *inode);
360 int z_erofs_map_blocks_iter(struct inode *inode,
361 struct erofs_map_blocks *map,
364 static inline int z_erofs_fill_inode(struct inode *inode) { return -EOPNOTSUPP; }
365 static inline int z_erofs_map_blocks_iter(struct inode *inode,
366 struct erofs_map_blocks *map,
371 #endif /* !CONFIG_EROFS_FS_ZIP */
374 struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr);
377 static inline unsigned long erofs_inode_hash(erofs_nid_t nid)
379 #if BITS_PER_LONG == 32
380 return (nid >> 32) ^ (nid & 0xffffffff);
386 extern const struct inode_operations erofs_generic_iops;
387 extern const struct inode_operations erofs_symlink_iops;
388 extern const struct inode_operations erofs_fast_symlink_iops;
390 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid, bool dir);
391 int erofs_getattr(struct user_namespace *mnt_userns, const struct path *path,
392 struct kstat *stat, u32 request_mask,
393 unsigned int query_flags);
396 extern const struct inode_operations erofs_dir_iops;
398 int erofs_namei(struct inode *dir, struct qstr *name,
399 erofs_nid_t *nid, unsigned int *d_type);
402 extern const struct file_operations erofs_dir_fops;
404 static inline void *erofs_vm_map_ram(struct page **pages, unsigned int count)
409 void *p = vm_map_ram(pages, count, -1);
411 /* retry two more times (totally 3 times) */
412 if (p || ++retried >= 3)
420 void *erofs_get_pcpubuf(unsigned int requiredpages);
421 void erofs_put_pcpubuf(void *ptr);
422 int erofs_pcpubuf_growsize(unsigned int nrpages);
423 void erofs_pcpubuf_init(void);
424 void erofs_pcpubuf_exit(void);
426 /* utils.c / zdata.c */
427 struct page *erofs_allocpage(struct list_head *pool, gfp_t gfp);
429 #ifdef CONFIG_EROFS_FS_ZIP
430 int erofs_workgroup_put(struct erofs_workgroup *grp);
431 struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb,
433 struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb,
434 struct erofs_workgroup *grp);
435 void erofs_workgroup_free_rcu(struct erofs_workgroup *grp);
436 void erofs_shrinker_register(struct super_block *sb);
437 void erofs_shrinker_unregister(struct super_block *sb);
438 int __init erofs_init_shrinker(void);
439 void erofs_exit_shrinker(void);
440 int __init z_erofs_init_zip_subsystem(void);
441 void z_erofs_exit_zip_subsystem(void);
442 int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
443 struct erofs_workgroup *egrp);
444 int erofs_try_to_free_cached_page(struct address_space *mapping,
446 int z_erofs_load_lz4_config(struct super_block *sb,
447 struct erofs_super_block *dsb,
448 struct z_erofs_lz4_cfgs *lz4, int len);
450 static inline void erofs_shrinker_register(struct super_block *sb) {}
451 static inline void erofs_shrinker_unregister(struct super_block *sb) {}
452 static inline int erofs_init_shrinker(void) { return 0; }
453 static inline void erofs_exit_shrinker(void) {}
454 static inline int z_erofs_init_zip_subsystem(void) { return 0; }
455 static inline void z_erofs_exit_zip_subsystem(void) {}
456 static inline int z_erofs_load_lz4_config(struct super_block *sb,
457 struct erofs_super_block *dsb,
458 struct z_erofs_lz4_cfgs *lz4, int len)
460 if (lz4 || dsb->u1.lz4_max_distance) {
461 erofs_err(sb, "lz4 algorithm isn't enabled");
466 #endif /* !CONFIG_EROFS_FS_ZIP */
468 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
470 #endif /* __EROFS_INTERNAL_H */