1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Copyright (C) 2017-2018 HUAWEI, Inc.
4 * https://www.huawei.com/
5 * Copyright (C) 2021, Alibaba Cloud
7 #ifndef __EROFS_INTERNAL_H
8 #define __EROFS_INTERNAL_H
11 #include <linux/dcache.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>
22 /* redefine pr_fmt "erofs: " */
24 #define pr_fmt(fmt) "erofs: " fmt
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
38 #define erofs_dbg(x, ...) ((void)0)
39 #define DBG_BUGON(x) ((void)(x))
40 #endif /* !CONFIG_EROFS_FS_DEBUG */
42 /* EROFS_SUPER_MAGIC_V1 to represent the whole file system */
43 #define EROFS_SUPER_MAGIC EROFS_SUPER_MAGIC_V1
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;
50 struct erofs_fs_context {
51 #ifdef CONFIG_EROFS_FS_ZIP
52 /* current strategy of how to use managed cache */
53 unsigned char cache_strategy;
54 /* strategy of sync decompression (false - auto, true - force on) */
55 bool readahead_sync_decompress;
57 /* threshold for decompression synchronously */
58 unsigned int max_sync_decompress_pages;
60 unsigned int mount_opt;
63 /* all filesystem-wide lz4 configurations */
64 struct erofs_sb_lz4_info {
65 /* # of pages needed for EROFS lz4 rolling decompression */
66 u16 max_distance_pages;
67 /* maximum possible blocks for pclusters in the filesystem */
71 struct erofs_sb_info {
72 #ifdef CONFIG_EROFS_FS_ZIP
73 /* list for all registered superblocks, mainly for shrinker */
74 struct list_head list;
75 struct mutex umount_mutex;
77 /* managed XArray arranged in physical block number */
78 struct xarray managed_pslots;
80 unsigned int shrinker_run_no;
81 u16 available_compr_algs;
83 /* pseudo inode to manage cached pages */
84 struct inode *managed_cache;
86 struct erofs_sb_lz4_info lz4;
87 #endif /* CONFIG_EROFS_FS_ZIP */
88 struct dax_device *dax_dev;
91 #ifdef CONFIG_EROFS_FS_XATTR
95 /* inode slot unit size in bit shift */
96 unsigned char islotbits;
98 u32 sb_size; /* total superblock size */
102 /* what we really care is nid, rather than ino.. */
103 erofs_nid_t root_nid;
104 /* used for statfs, f_files - f_favail */
107 u8 uuid[16]; /* 128-bit uuid for volume */
108 u8 volume_name[16]; /* volume name */
110 u32 feature_incompat;
112 struct erofs_fs_context ctx; /* options */
115 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
116 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)
118 /* Mount flags set via mount options or defaults */
119 #define EROFS_MOUNT_XATTR_USER 0x00000010
120 #define EROFS_MOUNT_POSIX_ACL 0x00000020
121 #define EROFS_MOUNT_DAX_ALWAYS 0x00000040
122 #define EROFS_MOUNT_DAX_NEVER 0x00000080
124 #define clear_opt(ctx, option) ((ctx)->mount_opt &= ~EROFS_MOUNT_##option)
125 #define set_opt(ctx, option) ((ctx)->mount_opt |= EROFS_MOUNT_##option)
126 #define test_opt(ctx, option) ((ctx)->mount_opt & EROFS_MOUNT_##option)
129 EROFS_ZIP_CACHE_DISABLED,
130 EROFS_ZIP_CACHE_READAHEAD,
131 EROFS_ZIP_CACHE_READAROUND
134 #ifdef CONFIG_EROFS_FS_ZIP
135 #define EROFS_LOCKED_MAGIC (INT_MIN | 0xE0F510CCL)
137 /* basic unit of the workstation of a super_block */
138 struct erofs_workgroup {
139 /* the workgroup index in the workstation */
142 /* overall workgroup reference count */
146 #if defined(CONFIG_SMP)
147 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
151 if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) {
158 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
162 * other observers should notice all modifications
163 * in the freezing period.
166 atomic_set(&grp->refcount, orig_val);
170 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
172 return atomic_cond_read_relaxed(&grp->refcount,
173 VAL != EROFS_LOCKED_MAGIC);
176 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
180 /* no need to spin on UP platforms, let's just disable preemption. */
181 if (val != atomic_read(&grp->refcount)) {
188 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
194 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
196 int v = atomic_read(&grp->refcount);
198 /* workgroup is never freezed on uniprocessor systems */
199 DBG_BUGON(v == EROFS_LOCKED_MAGIC);
202 #endif /* !CONFIG_SMP */
203 #endif /* !CONFIG_EROFS_FS_ZIP */
205 /* we strictly follow PAGE_SIZE and no buffer head yet */
206 #define LOG_BLOCK_SIZE PAGE_SHIFT
208 #undef LOG_SECTORS_PER_BLOCK
209 #define LOG_SECTORS_PER_BLOCK (PAGE_SHIFT - 9)
211 #undef SECTORS_PER_BLOCK
212 #define SECTORS_PER_BLOCK (1 << SECTORS_PER_BLOCK)
214 #define EROFS_BLKSIZ (1 << LOG_BLOCK_SIZE)
216 #if (EROFS_BLKSIZ % 4096 || !EROFS_BLKSIZ)
217 #error erofs cannot be used in this platform
220 #define ROOT_NID(sb) ((sb)->root_nid)
222 #define erofs_blknr(addr) ((addr) / EROFS_BLKSIZ)
223 #define erofs_blkoff(addr) ((addr) % EROFS_BLKSIZ)
224 #define blknr_to_addr(nr) ((erofs_off_t)(nr) * EROFS_BLKSIZ)
226 static inline erofs_off_t iloc(struct erofs_sb_info *sbi, erofs_nid_t nid)
228 return blknr_to_addr(sbi->meta_blkaddr) + (nid << sbi->islotbits);
231 #define EROFS_FEATURE_FUNCS(name, compat, feature) \
232 static inline bool erofs_sb_has_##name(struct erofs_sb_info *sbi) \
234 return sbi->feature_##compat & EROFS_FEATURE_##feature; \
237 EROFS_FEATURE_FUNCS(lz4_0padding, incompat, INCOMPAT_LZ4_0PADDING)
238 EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS)
239 EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER)
240 EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
242 /* atomic flag definitions */
243 #define EROFS_I_EA_INITED_BIT 0
244 #define EROFS_I_Z_INITED_BIT 1
246 /* bitlock definitions (arranged in reverse order) */
247 #define EROFS_I_BL_XATTR_BIT (BITS_PER_LONG - 1)
248 #define EROFS_I_BL_Z_BIT (BITS_PER_LONG - 2)
253 /* atomic flags (including bitlocks) */
256 unsigned char datalayout;
257 unsigned char inode_isize;
258 unsigned short xattr_isize;
260 unsigned int xattr_shared_count;
261 unsigned int *xattr_shared_xattrs;
264 erofs_blk_t raw_blkaddr;
266 unsigned short chunkformat;
267 unsigned char chunkbits;
269 #ifdef CONFIG_EROFS_FS_ZIP
271 unsigned short z_advise;
272 unsigned char z_algorithmtype[2];
273 unsigned char z_logical_clusterbits;
275 #endif /* CONFIG_EROFS_FS_ZIP */
277 /* the corresponding vfs inode */
278 struct inode vfs_inode;
281 #define EROFS_I(ptr) \
282 container_of(ptr, struct erofs_inode, vfs_inode)
284 static inline unsigned long erofs_inode_datablocks(struct inode *inode)
286 /* since i_size cannot be changed */
287 return DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ);
290 static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit,
294 return (value >> bit) & ((1 << bits) - 1);
298 static inline unsigned int erofs_inode_version(unsigned int value)
300 return erofs_bitrange(value, EROFS_I_VERSION_BIT,
301 EROFS_I_VERSION_BITS);
304 static inline unsigned int erofs_inode_datalayout(unsigned int value)
306 return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT,
307 EROFS_I_DATALAYOUT_BITS);
310 extern const struct super_operations erofs_sops;
312 extern const struct address_space_operations erofs_raw_access_aops;
313 extern const struct address_space_operations z_erofs_aops;
316 * Logical to physical block mapping
318 * Different with other file systems, it is used for 2 access modes:
320 * 1) RAW access mode:
322 * Users pass a valid (m_lblk, m_lofs -- usually 0) pair,
323 * and get the valid m_pblk, m_pofs and the longest m_len(in bytes).
325 * Note that m_lblk in the RAW access mode refers to the number of
326 * the compressed ondisk block rather than the uncompressed
327 * in-memory block for the compressed file.
329 * m_pofs equals to m_lofs except for the inline data page.
331 * 2) Normal access mode:
333 * If the inode is not compressed, it has no difference with
334 * the RAW access mode. However, if the inode is compressed,
335 * users should pass a valid (m_lblk, m_lofs) pair, and get
336 * the needed m_pblk, m_pofs, m_len to get the compressed data
337 * and the updated m_lblk, m_lofs which indicates the start
338 * of the corresponding uncompressed data in the file.
341 BH_Zipped = BH_PrivateStart,
345 /* Has a disk mapping */
346 #define EROFS_MAP_MAPPED (1 << BH_Mapped)
347 /* Located in metadata (could be copied from bd_inode) */
348 #define EROFS_MAP_META (1 << BH_Meta)
349 /* The extent has been compressed */
350 #define EROFS_MAP_ZIPPED (1 << BH_Zipped)
351 /* The length of extent is full */
352 #define EROFS_MAP_FULL_MAPPED (1 << BH_FullMapped)
354 struct erofs_map_blocks {
355 erofs_off_t m_pa, m_la;
358 unsigned int m_flags;
363 /* Flags used by erofs_map_blocks_flatmode() */
364 #define EROFS_GET_BLOCKS_RAW 0x0001
366 * Used to get the exact decompressed length, e.g. fiemap (consider lookback
367 * approach instead if possible since it's more metadata lightweight.)
369 #define EROFS_GET_BLOCKS_FIEMAP 0x0002
372 extern const struct iomap_ops z_erofs_iomap_report_ops;
374 #ifdef CONFIG_EROFS_FS_ZIP
375 int z_erofs_fill_inode(struct inode *inode);
376 int z_erofs_map_blocks_iter(struct inode *inode,
377 struct erofs_map_blocks *map,
380 static inline int z_erofs_fill_inode(struct inode *inode) { return -EOPNOTSUPP; }
381 static inline int z_erofs_map_blocks_iter(struct inode *inode,
382 struct erofs_map_blocks *map,
387 #endif /* !CONFIG_EROFS_FS_ZIP */
390 extern const struct file_operations erofs_file_fops;
391 struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr);
392 int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
396 static inline unsigned long erofs_inode_hash(erofs_nid_t nid)
398 #if BITS_PER_LONG == 32
399 return (nid >> 32) ^ (nid & 0xffffffff);
405 extern const struct inode_operations erofs_generic_iops;
406 extern const struct inode_operations erofs_symlink_iops;
407 extern const struct inode_operations erofs_fast_symlink_iops;
409 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid, bool dir);
410 int erofs_getattr(struct user_namespace *mnt_userns, const struct path *path,
411 struct kstat *stat, u32 request_mask,
412 unsigned int query_flags);
415 extern const struct inode_operations erofs_dir_iops;
417 int erofs_namei(struct inode *dir, struct qstr *name,
418 erofs_nid_t *nid, unsigned int *d_type);
421 extern const struct file_operations erofs_dir_fops;
423 static inline void *erofs_vm_map_ram(struct page **pages, unsigned int count)
428 void *p = vm_map_ram(pages, count, -1);
430 /* retry two more times (totally 3 times) */
431 if (p || ++retried >= 3)
439 void *erofs_get_pcpubuf(unsigned int requiredpages);
440 void erofs_put_pcpubuf(void *ptr);
441 int erofs_pcpubuf_growsize(unsigned int nrpages);
442 void erofs_pcpubuf_init(void);
443 void erofs_pcpubuf_exit(void);
445 /* utils.c / zdata.c */
446 struct page *erofs_allocpage(struct list_head *pool, gfp_t gfp);
448 #ifdef CONFIG_EROFS_FS_ZIP
449 int erofs_workgroup_put(struct erofs_workgroup *grp);
450 struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb,
452 struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb,
453 struct erofs_workgroup *grp);
454 void erofs_workgroup_free_rcu(struct erofs_workgroup *grp);
455 void erofs_shrinker_register(struct super_block *sb);
456 void erofs_shrinker_unregister(struct super_block *sb);
457 int __init erofs_init_shrinker(void);
458 void erofs_exit_shrinker(void);
459 int __init z_erofs_init_zip_subsystem(void);
460 void z_erofs_exit_zip_subsystem(void);
461 int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
462 struct erofs_workgroup *egrp);
463 int erofs_try_to_free_cached_page(struct page *page);
464 int z_erofs_load_lz4_config(struct super_block *sb,
465 struct erofs_super_block *dsb,
466 struct z_erofs_lz4_cfgs *lz4, int len);
468 static inline void erofs_shrinker_register(struct super_block *sb) {}
469 static inline void erofs_shrinker_unregister(struct super_block *sb) {}
470 static inline int erofs_init_shrinker(void) { return 0; }
471 static inline void erofs_exit_shrinker(void) {}
472 static inline int z_erofs_init_zip_subsystem(void) { return 0; }
473 static inline void z_erofs_exit_zip_subsystem(void) {}
474 static inline int z_erofs_load_lz4_config(struct super_block *sb,
475 struct erofs_super_block *dsb,
476 struct z_erofs_lz4_cfgs *lz4, int len)
478 if (lz4 || dsb->u1.lz4_max_distance) {
479 erofs_err(sb, "lz4 algorithm isn't enabled");
484 #endif /* !CONFIG_EROFS_FS_ZIP */
486 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
488 #endif /* __EROFS_INTERNAL_H */