tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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/dax.h>
12#include <linux/dcache.h>
13#include <linux/mm.h>
14#include <linux/module.h>
15#include <linux/pagemap.h>
16#include <linux/bio.h>
17#include <linux/magic.h>
18#include <linux/slab.h>
19#include <linux/vmalloc.h>
20#include <linux/iomap.h>
21#include "erofs_fs.h"
22
23__printf(2, 3) void _erofs_printk(struct super_block *sb, const char *fmt, ...);
24#define erofs_err(sb, fmt, ...) \
25 _erofs_printk(sb, KERN_ERR fmt "\n", ##__VA_ARGS__)
26#define erofs_info(sb, fmt, ...) \
27 _erofs_printk(sb, KERN_INFO fmt "\n", ##__VA_ARGS__)
28
29#ifdef CONFIG_EROFS_FS_DEBUG
30#define DBG_BUGON BUG_ON
31#else
32#define DBG_BUGON(x) ((void)(x))
33#endif /* !CONFIG_EROFS_FS_DEBUG */
34
35/* EROFS_SUPER_MAGIC_V1 to represent the whole file system */
36#define EROFS_SUPER_MAGIC EROFS_SUPER_MAGIC_V1
37
38typedef u64 erofs_nid_t;
39typedef u64 erofs_off_t;
40typedef u64 erofs_blk_t;
41
42struct erofs_device_info {
43 char *path;
44 struct erofs_fscache *fscache;
45 struct file *file;
46 struct dax_device *dax_dev;
47 u64 dax_part_off;
48
49 erofs_blk_t blocks;
50 erofs_blk_t uniaddr;
51};
52
53enum {
54 EROFS_SYNC_DECOMPRESS_AUTO,
55 EROFS_SYNC_DECOMPRESS_FORCE_ON,
56 EROFS_SYNC_DECOMPRESS_FORCE_OFF
57};
58
59struct erofs_mount_opts {
60 /* current strategy of how to use managed cache */
61 unsigned char cache_strategy;
62 /* strategy of sync decompression (0 - auto, 1 - force on, 2 - force off) */
63 unsigned int sync_decompress;
64 /* threshold for decompression synchronously */
65 unsigned int max_sync_decompress_pages;
66 unsigned int mount_opt;
67};
68
69struct erofs_dev_context {
70 struct idr tree;
71 struct rw_semaphore rwsem;
72
73 unsigned int extra_devices;
74 bool flatdev;
75};
76
77/* all filesystem-wide lz4 configurations */
78struct erofs_sb_lz4_info {
79 /* # of pages needed for EROFS lz4 rolling decompression */
80 u16 max_distance_pages;
81 /* maximum possible blocks for pclusters in the filesystem */
82 u16 max_pclusterblks;
83};
84
85struct erofs_domain {
86 refcount_t ref;
87 struct list_head list;
88 struct fscache_volume *volume;
89 char *domain_id;
90};
91
92struct erofs_fscache {
93 struct fscache_cookie *cookie;
94 struct inode *inode; /* anonymous inode for the blob */
95
96 /* used for share domain mode */
97 struct erofs_domain *domain;
98 struct list_head node;
99 refcount_t ref;
100 char *name;
101};
102
103struct erofs_xattr_prefix_item {
104 struct erofs_xattr_long_prefix *prefix;
105 u8 infix_len;
106};
107
108struct erofs_sb_info {
109 struct erofs_device_info dif0;
110 struct erofs_mount_opts opt; /* options */
111#ifdef CONFIG_EROFS_FS_ZIP
112 /* list for all registered superblocks, mainly for shrinker */
113 struct list_head list;
114 struct mutex umount_mutex;
115
116 /* managed XArray arranged in physical block number */
117 struct xarray managed_pslots;
118
119 unsigned int shrinker_run_no;
120 u16 available_compr_algs;
121
122 /* pseudo inode to manage cached pages */
123 struct inode *managed_cache;
124
125 struct erofs_sb_lz4_info lz4;
126#endif /* CONFIG_EROFS_FS_ZIP */
127 struct inode *packed_inode;
128 struct erofs_dev_context *devs;
129 u64 total_blocks;
130
131 u32 meta_blkaddr;
132#ifdef CONFIG_EROFS_FS_XATTR
133 u32 xattr_blkaddr;
134 u32 xattr_prefix_start;
135 u8 xattr_prefix_count;
136 struct erofs_xattr_prefix_item *xattr_prefixes;
137 unsigned int xattr_filter_reserved;
138#endif
139 u16 device_id_mask; /* valid bits of device id to be used */
140
141 unsigned char islotbits; /* inode slot unit size in bit shift */
142 unsigned char blkszbits; /* filesystem block size in bit shift */
143
144 u32 sb_size; /* total superblock size */
145 u32 fixed_nsec;
146 s64 epoch;
147
148 /* what we really care is nid, rather than ino.. */
149 erofs_nid_t root_nid;
150 erofs_nid_t packed_nid;
151 /* used for statfs, f_files - f_favail */
152 u64 inos;
153
154 u32 feature_compat;
155 u32 feature_incompat;
156
157 /* sysfs support */
158 struct kobject s_kobj; /* /sys/fs/erofs/<devname> */
159 struct completion s_kobj_unregister;
160
161 /* fscache support */
162 struct fscache_volume *volume;
163 struct erofs_domain *domain;
164 char *fsid;
165 char *domain_id;
166};
167
168#define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
169#define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)
170
171/* Mount flags set via mount options or defaults */
172#define EROFS_MOUNT_XATTR_USER 0x00000010
173#define EROFS_MOUNT_POSIX_ACL 0x00000020
174#define EROFS_MOUNT_DAX_ALWAYS 0x00000040
175#define EROFS_MOUNT_DAX_NEVER 0x00000080
176#define EROFS_MOUNT_DIRECT_IO 0x00000100
177
178#define clear_opt(opt, option) ((opt)->mount_opt &= ~EROFS_MOUNT_##option)
179#define set_opt(opt, option) ((opt)->mount_opt |= EROFS_MOUNT_##option)
180#define test_opt(opt, option) ((opt)->mount_opt & EROFS_MOUNT_##option)
181
182static inline bool erofs_is_fileio_mode(struct erofs_sb_info *sbi)
183{
184 return IS_ENABLED(CONFIG_EROFS_FS_BACKED_BY_FILE) && sbi->dif0.file;
185}
186
187static inline bool erofs_is_fscache_mode(struct super_block *sb)
188{
189 return IS_ENABLED(CONFIG_EROFS_FS_ONDEMAND) &&
190 !erofs_is_fileio_mode(EROFS_SB(sb)) && !sb->s_bdev;
191}
192
193enum {
194 EROFS_ZIP_CACHE_DISABLED,
195 EROFS_ZIP_CACHE_READAHEAD,
196 EROFS_ZIP_CACHE_READAROUND
197};
198
199struct erofs_buf {
200 struct address_space *mapping;
201 struct file *file;
202 struct page *page;
203 void *base;
204};
205#define __EROFS_BUF_INITIALIZER ((struct erofs_buf){ .page = NULL })
206
207#define erofs_blknr(sb, pos) ((erofs_blk_t)((pos) >> (sb)->s_blocksize_bits))
208#define erofs_blkoff(sb, pos) ((pos) & ((sb)->s_blocksize - 1))
209#define erofs_pos(sb, blk) ((erofs_off_t)(blk) << (sb)->s_blocksize_bits)
210#define erofs_iblks(i) (round_up((i)->i_size, i_blocksize(i)) >> (i)->i_blkbits)
211
212#define EROFS_FEATURE_FUNCS(name, compat, feature) \
213static inline bool erofs_sb_has_##name(struct erofs_sb_info *sbi) \
214{ \
215 return sbi->feature_##compat & EROFS_FEATURE_##feature; \
216}
217
218EROFS_FEATURE_FUNCS(zero_padding, incompat, INCOMPAT_ZERO_PADDING)
219EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS)
220EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER)
221EROFS_FEATURE_FUNCS(chunked_file, incompat, INCOMPAT_CHUNKED_FILE)
222EROFS_FEATURE_FUNCS(device_table, incompat, INCOMPAT_DEVICE_TABLE)
223EROFS_FEATURE_FUNCS(compr_head2, incompat, INCOMPAT_COMPR_HEAD2)
224EROFS_FEATURE_FUNCS(ztailpacking, incompat, INCOMPAT_ZTAILPACKING)
225EROFS_FEATURE_FUNCS(fragments, incompat, INCOMPAT_FRAGMENTS)
226EROFS_FEATURE_FUNCS(dedupe, incompat, INCOMPAT_DEDUPE)
227EROFS_FEATURE_FUNCS(xattr_prefixes, incompat, INCOMPAT_XATTR_PREFIXES)
228EROFS_FEATURE_FUNCS(48bit, incompat, INCOMPAT_48BIT)
229EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
230EROFS_FEATURE_FUNCS(xattr_filter, compat, COMPAT_XATTR_FILTER)
231
232/* atomic flag definitions */
233#define EROFS_I_EA_INITED_BIT 0
234#define EROFS_I_Z_INITED_BIT 1
235
236/* bitlock definitions (arranged in reverse order) */
237#define EROFS_I_BL_XATTR_BIT (BITS_PER_LONG - 1)
238#define EROFS_I_BL_Z_BIT (BITS_PER_LONG - 2)
239
240struct erofs_inode {
241 erofs_nid_t nid;
242
243 /* atomic flags (including bitlocks) */
244 unsigned long flags;
245
246 unsigned char datalayout;
247 unsigned char inode_isize;
248 bool dot_omitted;
249 unsigned int xattr_isize;
250
251 unsigned int xattr_name_filter;
252 unsigned int xattr_shared_count;
253 unsigned int *xattr_shared_xattrs;
254
255 union {
256 erofs_blk_t startblk;
257 struct {
258 unsigned short chunkformat;
259 unsigned char chunkbits;
260 };
261#ifdef CONFIG_EROFS_FS_ZIP
262 struct {
263 unsigned short z_advise;
264 unsigned char z_algorithmtype[2];
265 unsigned char z_lclusterbits;
266 union {
267 u64 z_tailextent_headlcn;
268 u64 z_extents;
269 };
270 erofs_off_t z_fragmentoff;
271 unsigned short z_idata_size;
272 };
273#endif /* CONFIG_EROFS_FS_ZIP */
274 };
275 /* the corresponding vfs inode */
276 struct inode vfs_inode;
277};
278
279#define EROFS_I(ptr) container_of(ptr, struct erofs_inode, vfs_inode)
280
281static inline erofs_off_t erofs_iloc(struct inode *inode)
282{
283 struct erofs_sb_info *sbi = EROFS_I_SB(inode);
284
285 return erofs_pos(inode->i_sb, sbi->meta_blkaddr) +
286 (EROFS_I(inode)->nid << sbi->islotbits);
287}
288
289static inline unsigned int erofs_inode_version(unsigned int ifmt)
290{
291 return (ifmt >> EROFS_I_VERSION_BIT) & EROFS_I_VERSION_MASK;
292}
293
294static inline unsigned int erofs_inode_datalayout(unsigned int ifmt)
295{
296 return (ifmt >> EROFS_I_DATALAYOUT_BIT) & EROFS_I_DATALAYOUT_MASK;
297}
298
299/* reclaiming is never triggered when allocating new folios. */
300static inline struct folio *erofs_grab_folio_nowait(struct address_space *as,
301 pgoff_t index)
302{
303 return __filemap_get_folio(as, index,
304 FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT,
305 readahead_gfp_mask(as) & ~__GFP_RECLAIM);
306}
307
308/* Has a disk mapping */
309#define EROFS_MAP_MAPPED 0x0001
310/* Located in metadata (could be copied from bd_inode) */
311#define EROFS_MAP_META 0x0002
312/* The extent is encoded */
313#define EROFS_MAP_ENCODED 0x0004
314/* The length of extent is full */
315#define EROFS_MAP_FULL_MAPPED 0x0008
316/* Located in the special packed inode */
317#define EROFS_MAP_FRAGMENT 0x0010
318/* The extent refers to partial decompressed data */
319#define EROFS_MAP_PARTIAL_REF 0x0020
320
321struct erofs_map_blocks {
322 struct erofs_buf buf;
323
324 erofs_off_t m_pa, m_la;
325 u64 m_plen, m_llen;
326
327 unsigned short m_deviceid;
328 char m_algorithmformat;
329 unsigned int m_flags;
330};
331
332/*
333 * Used to get the exact decompressed length, e.g. fiemap (consider lookback
334 * approach instead if possible since it's more metadata lightweight.)
335 */
336#define EROFS_GET_BLOCKS_FIEMAP 0x0001
337/* Used to map the whole extent if non-negligible data is requested for LZMA */
338#define EROFS_GET_BLOCKS_READMORE 0x0002
339/* Used to map tail extent for tailpacking inline or fragment pcluster */
340#define EROFS_GET_BLOCKS_FINDTAIL 0x0004
341
342enum {
343 Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX,
344 Z_EROFS_COMPRESSION_INTERLACED,
345 Z_EROFS_COMPRESSION_RUNTIME_MAX
346};
347
348struct erofs_map_dev {
349 struct super_block *m_sb;
350 struct erofs_device_info *m_dif;
351 struct block_device *m_bdev;
352
353 erofs_off_t m_pa;
354 unsigned int m_deviceid;
355};
356
357extern const struct super_operations erofs_sops;
358
359extern const struct address_space_operations erofs_aops;
360extern const struct address_space_operations erofs_fileio_aops;
361extern const struct address_space_operations z_erofs_aops;
362extern const struct address_space_operations erofs_fscache_access_aops;
363
364extern const struct inode_operations erofs_generic_iops;
365extern const struct inode_operations erofs_symlink_iops;
366extern const struct inode_operations erofs_fast_symlink_iops;
367extern const struct inode_operations erofs_dir_iops;
368
369extern const struct file_operations erofs_file_fops;
370extern const struct file_operations erofs_dir_fops;
371
372extern const struct iomap_ops z_erofs_iomap_report_ops;
373
374/* flags for erofs_fscache_register_cookie() */
375#define EROFS_REG_COOKIE_SHARE 0x0001
376#define EROFS_REG_COOKIE_NEED_NOEXIST 0x0002
377
378void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf,
379 erofs_off_t *offset, int *lengthp);
380void erofs_unmap_metabuf(struct erofs_buf *buf);
381void erofs_put_metabuf(struct erofs_buf *buf);
382void *erofs_bread(struct erofs_buf *buf, erofs_off_t offset, bool need_kmap);
383void erofs_init_metabuf(struct erofs_buf *buf, struct super_block *sb);
384void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,
385 erofs_off_t offset, bool need_kmap);
386int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *dev);
387int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
388 u64 start, u64 len);
389int erofs_map_blocks(struct inode *inode, struct erofs_map_blocks *map);
390void erofs_onlinefolio_init(struct folio *folio);
391void erofs_onlinefolio_split(struct folio *folio);
392void erofs_onlinefolio_end(struct folio *folio, int err);
393struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid);
394int erofs_getattr(struct mnt_idmap *idmap, const struct path *path,
395 struct kstat *stat, u32 request_mask,
396 unsigned int query_flags);
397int erofs_namei(struct inode *dir, const struct qstr *name,
398 erofs_nid_t *nid, unsigned int *d_type);
399
400static inline void *erofs_vm_map_ram(struct page **pages, unsigned int count)
401{
402 int retried = 0;
403
404 while (1) {
405 void *p = vm_map_ram(pages, count, -1);
406
407 /* retry two more times (totally 3 times) */
408 if (p || ++retried >= 3)
409 return p;
410 vm_unmap_aliases();
411 }
412 return NULL;
413}
414
415int erofs_register_sysfs(struct super_block *sb);
416void erofs_unregister_sysfs(struct super_block *sb);
417int __init erofs_init_sysfs(void);
418void erofs_exit_sysfs(void);
419
420struct page *__erofs_allocpage(struct page **pagepool, gfp_t gfp, bool tryrsv);
421static inline struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp)
422{
423 return __erofs_allocpage(pagepool, gfp, false);
424}
425static inline void erofs_pagepool_add(struct page **pagepool, struct page *page)
426{
427 set_page_private(page, (unsigned long)*pagepool);
428 *pagepool = page;
429}
430void erofs_release_pages(struct page **pagepool);
431
432#ifdef CONFIG_EROFS_FS_ZIP
433#define MNGD_MAPPING(sbi) ((sbi)->managed_cache->i_mapping)
434
435extern atomic_long_t erofs_global_shrink_cnt;
436void erofs_shrinker_register(struct super_block *sb);
437void erofs_shrinker_unregister(struct super_block *sb);
438int __init erofs_init_shrinker(void);
439void erofs_exit_shrinker(void);
440int __init z_erofs_init_subsystem(void);
441void z_erofs_exit_subsystem(void);
442int z_erofs_init_super(struct super_block *sb);
443unsigned long z_erofs_shrink_scan(struct erofs_sb_info *sbi,
444 unsigned long nr_shrink);
445int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map,
446 int flags);
447void *z_erofs_get_gbuf(unsigned int requiredpages);
448void z_erofs_put_gbuf(void *ptr);
449int z_erofs_gbuf_growsize(unsigned int nrpages);
450int __init z_erofs_gbuf_init(void);
451void z_erofs_gbuf_exit(void);
452int z_erofs_parse_cfgs(struct super_block *sb, struct erofs_super_block *dsb);
453#else
454static inline void erofs_shrinker_register(struct super_block *sb) {}
455static inline void erofs_shrinker_unregister(struct super_block *sb) {}
456static inline int erofs_init_shrinker(void) { return 0; }
457static inline void erofs_exit_shrinker(void) {}
458static inline int z_erofs_init_subsystem(void) { return 0; }
459static inline void z_erofs_exit_subsystem(void) {}
460static inline int z_erofs_init_super(struct super_block *sb) { return 0; }
461#endif /* !CONFIG_EROFS_FS_ZIP */
462
463#ifdef CONFIG_EROFS_FS_BACKED_BY_FILE
464struct bio *erofs_fileio_bio_alloc(struct erofs_map_dev *mdev);
465void erofs_fileio_submit_bio(struct bio *bio);
466#else
467static inline struct bio *erofs_fileio_bio_alloc(struct erofs_map_dev *mdev) { return NULL; }
468static inline void erofs_fileio_submit_bio(struct bio *bio) {}
469#endif
470
471#ifdef CONFIG_EROFS_FS_ONDEMAND
472int erofs_fscache_register_fs(struct super_block *sb);
473void erofs_fscache_unregister_fs(struct super_block *sb);
474
475struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
476 char *name, unsigned int flags);
477void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache);
478struct bio *erofs_fscache_bio_alloc(struct erofs_map_dev *mdev);
479void erofs_fscache_submit_bio(struct bio *bio);
480#else
481static inline int erofs_fscache_register_fs(struct super_block *sb)
482{
483 return -EOPNOTSUPP;
484}
485static inline void erofs_fscache_unregister_fs(struct super_block *sb) {}
486
487static inline
488struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
489 char *name, unsigned int flags)
490{
491 return ERR_PTR(-EOPNOTSUPP);
492}
493
494static inline void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache)
495{
496}
497static inline struct bio *erofs_fscache_bio_alloc(struct erofs_map_dev *mdev) { return NULL; }
498static inline void erofs_fscache_submit_bio(struct bio *bio) {}
499#endif
500
501#define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
502
503#endif /* __EROFS_INTERNAL_H */