xref: /linux/fs/erofs/internal.h (revision 8de4ed75bd14ed197119ac509c6902a8561e0c1c)
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 /* redefine pr_fmt "erofs: " */
24 #undef pr_fmt
25 #define pr_fmt(fmt) "erofs: " fmt
26 
27 __printf(3, 4) void _erofs_err(struct super_block *sb,
28 			       const char *function, const char *fmt, ...);
29 #define erofs_err(sb, fmt, ...)	\
30 	_erofs_err(sb, __func__, fmt "\n", ##__VA_ARGS__)
31 __printf(3, 4) void _erofs_info(struct super_block *sb,
32 			       const char *function, const char *fmt, ...);
33 #define erofs_info(sb, fmt, ...) \
34 	_erofs_info(sb, __func__, fmt "\n", ##__VA_ARGS__)
35 #ifdef CONFIG_EROFS_FS_DEBUG
36 #define DBG_BUGON               BUG_ON
37 #else
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_device_info {
50 	char *path;
51 	struct erofs_fscache *fscache;
52 	struct file *bdev_file;
53 	struct dax_device *dax_dev;
54 	u64 dax_part_off;
55 
56 	u32 blocks;
57 	u32 mapped_blkaddr;
58 };
59 
60 enum {
61 	EROFS_SYNC_DECOMPRESS_AUTO,
62 	EROFS_SYNC_DECOMPRESS_FORCE_ON,
63 	EROFS_SYNC_DECOMPRESS_FORCE_OFF
64 };
65 
66 struct erofs_mount_opts {
67 	/* current strategy of how to use managed cache */
68 	unsigned char cache_strategy;
69 	/* strategy of sync decompression (0 - auto, 1 - force on, 2 - force off) */
70 	unsigned int sync_decompress;
71 	/* threshold for decompression synchronously */
72 	unsigned int max_sync_decompress_pages;
73 	unsigned int mount_opt;
74 };
75 
76 struct erofs_dev_context {
77 	struct idr tree;
78 	struct rw_semaphore rwsem;
79 
80 	unsigned int extra_devices;
81 	bool flatdev;
82 };
83 
84 /* all filesystem-wide lz4 configurations */
85 struct erofs_sb_lz4_info {
86 	/* # of pages needed for EROFS lz4 rolling decompression */
87 	u16 max_distance_pages;
88 	/* maximum possible blocks for pclusters in the filesystem */
89 	u16 max_pclusterblks;
90 };
91 
92 struct erofs_domain {
93 	refcount_t ref;
94 	struct list_head list;
95 	struct fscache_volume *volume;
96 	char *domain_id;
97 };
98 
99 struct erofs_fscache {
100 	struct fscache_cookie *cookie;
101 	struct inode *inode;	/* anonymous inode for the blob */
102 
103 	/* used for share domain mode */
104 	struct erofs_domain *domain;
105 	struct list_head node;
106 	refcount_t ref;
107 	char *name;
108 };
109 
110 struct erofs_xattr_prefix_item {
111 	struct erofs_xattr_long_prefix *prefix;
112 	u8 infix_len;
113 };
114 
115 struct erofs_sb_info {
116 	struct erofs_mount_opts opt;	/* options */
117 #ifdef CONFIG_EROFS_FS_ZIP
118 	/* list for all registered superblocks, mainly for shrinker */
119 	struct list_head list;
120 	struct mutex umount_mutex;
121 
122 	/* managed XArray arranged in physical block number */
123 	struct xarray managed_pslots;
124 
125 	unsigned int shrinker_run_no;
126 	u16 available_compr_algs;
127 
128 	/* pseudo inode to manage cached pages */
129 	struct inode *managed_cache;
130 
131 	struct erofs_sb_lz4_info lz4;
132 #endif	/* CONFIG_EROFS_FS_ZIP */
133 	struct inode *packed_inode;
134 	struct erofs_dev_context *devs;
135 	struct dax_device *dax_dev;
136 	u64 dax_part_off;
137 	u64 total_blocks;
138 	u32 primarydevice_blocks;
139 
140 	u32 meta_blkaddr;
141 #ifdef CONFIG_EROFS_FS_XATTR
142 	u32 xattr_blkaddr;
143 	u32 xattr_prefix_start;
144 	u8 xattr_prefix_count;
145 	struct erofs_xattr_prefix_item *xattr_prefixes;
146 	unsigned int xattr_filter_reserved;
147 #endif
148 	u16 device_id_mask;	/* valid bits of device id to be used */
149 
150 	unsigned char islotbits;	/* inode slot unit size in bit shift */
151 	unsigned char blkszbits;	/* filesystem block size in bit shift */
152 
153 	u32 sb_size;			/* total superblock size */
154 	u32 build_time_nsec;
155 	u64 build_time;
156 
157 	/* what we really care is nid, rather than ino.. */
158 	erofs_nid_t root_nid;
159 	erofs_nid_t packed_nid;
160 	/* used for statfs, f_files - f_favail */
161 	u64 inos;
162 
163 	u8 uuid[16];                    /* 128-bit uuid for volume */
164 	u8 volume_name[16];             /* volume name */
165 	u32 feature_compat;
166 	u32 feature_incompat;
167 
168 	/* sysfs support */
169 	struct kobject s_kobj;		/* /sys/fs/erofs/<devname> */
170 	struct completion s_kobj_unregister;
171 
172 	/* fscache support */
173 	struct fscache_volume *volume;
174 	struct erofs_fscache *s_fscache;
175 	struct erofs_domain *domain;
176 	char *fsid;
177 	char *domain_id;
178 };
179 
180 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
181 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)
182 
183 /* Mount flags set via mount options or defaults */
184 #define EROFS_MOUNT_XATTR_USER		0x00000010
185 #define EROFS_MOUNT_POSIX_ACL		0x00000020
186 #define EROFS_MOUNT_DAX_ALWAYS		0x00000040
187 #define EROFS_MOUNT_DAX_NEVER		0x00000080
188 
189 #define clear_opt(opt, option)	((opt)->mount_opt &= ~EROFS_MOUNT_##option)
190 #define set_opt(opt, option)	((opt)->mount_opt |= EROFS_MOUNT_##option)
191 #define test_opt(opt, option)	((opt)->mount_opt & EROFS_MOUNT_##option)
192 
193 static inline bool erofs_is_fscache_mode(struct super_block *sb)
194 {
195 	return IS_ENABLED(CONFIG_EROFS_FS_ONDEMAND) && !sb->s_bdev;
196 }
197 
198 enum {
199 	EROFS_ZIP_CACHE_DISABLED,
200 	EROFS_ZIP_CACHE_READAHEAD,
201 	EROFS_ZIP_CACHE_READAROUND
202 };
203 
204 /* basic unit of the workstation of a super_block */
205 struct erofs_workgroup {
206 	pgoff_t index;
207 	struct lockref lockref;
208 };
209 
210 enum erofs_kmap_type {
211 	EROFS_NO_KMAP,		/* don't map the buffer */
212 	EROFS_KMAP,		/* use kmap_local_page() to map the buffer */
213 };
214 
215 struct erofs_buf {
216 	struct address_space *mapping;
217 	struct page *page;
218 	void *base;
219 	enum erofs_kmap_type kmap_type;
220 };
221 #define __EROFS_BUF_INITIALIZER	((struct erofs_buf){ .page = NULL })
222 
223 #define erofs_blknr(sb, addr)	((addr) >> (sb)->s_blocksize_bits)
224 #define erofs_blkoff(sb, addr)	((addr) & ((sb)->s_blocksize - 1))
225 #define erofs_pos(sb, blk)	((erofs_off_t)(blk) << (sb)->s_blocksize_bits)
226 #define erofs_iblks(i)	(round_up((i)->i_size, i_blocksize(i)) >> (i)->i_blkbits)
227 
228 #define EROFS_FEATURE_FUNCS(name, compat, feature) \
229 static inline bool erofs_sb_has_##name(struct erofs_sb_info *sbi) \
230 { \
231 	return sbi->feature_##compat & EROFS_FEATURE_##feature; \
232 }
233 
234 EROFS_FEATURE_FUNCS(zero_padding, incompat, INCOMPAT_ZERO_PADDING)
235 EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS)
236 EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER)
237 EROFS_FEATURE_FUNCS(chunked_file, incompat, INCOMPAT_CHUNKED_FILE)
238 EROFS_FEATURE_FUNCS(device_table, incompat, INCOMPAT_DEVICE_TABLE)
239 EROFS_FEATURE_FUNCS(compr_head2, incompat, INCOMPAT_COMPR_HEAD2)
240 EROFS_FEATURE_FUNCS(ztailpacking, incompat, INCOMPAT_ZTAILPACKING)
241 EROFS_FEATURE_FUNCS(fragments, incompat, INCOMPAT_FRAGMENTS)
242 EROFS_FEATURE_FUNCS(dedupe, incompat, INCOMPAT_DEDUPE)
243 EROFS_FEATURE_FUNCS(xattr_prefixes, incompat, INCOMPAT_XATTR_PREFIXES)
244 EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
245 EROFS_FEATURE_FUNCS(xattr_filter, compat, COMPAT_XATTR_FILTER)
246 
247 /* atomic flag definitions */
248 #define EROFS_I_EA_INITED_BIT	0
249 #define EROFS_I_Z_INITED_BIT	1
250 
251 /* bitlock definitions (arranged in reverse order) */
252 #define EROFS_I_BL_XATTR_BIT	(BITS_PER_LONG - 1)
253 #define EROFS_I_BL_Z_BIT	(BITS_PER_LONG - 2)
254 
255 struct erofs_inode {
256 	erofs_nid_t nid;
257 
258 	/* atomic flags (including bitlocks) */
259 	unsigned long flags;
260 
261 	unsigned char datalayout;
262 	unsigned char inode_isize;
263 	unsigned int xattr_isize;
264 
265 	unsigned int xattr_name_filter;
266 	unsigned int xattr_shared_count;
267 	unsigned int *xattr_shared_xattrs;
268 
269 	union {
270 		erofs_blk_t raw_blkaddr;
271 		struct {
272 			unsigned short	chunkformat;
273 			unsigned char	chunkbits;
274 		};
275 #ifdef CONFIG_EROFS_FS_ZIP
276 		struct {
277 			unsigned short z_advise;
278 			unsigned char  z_algorithmtype[2];
279 			unsigned char  z_logical_clusterbits;
280 			unsigned long  z_tailextent_headlcn;
281 			union {
282 				struct {
283 					erofs_off_t    z_idataoff;
284 					unsigned short z_idata_size;
285 				};
286 				erofs_off_t z_fragmentoff;
287 			};
288 		};
289 #endif	/* CONFIG_EROFS_FS_ZIP */
290 	};
291 	/* the corresponding vfs inode */
292 	struct inode vfs_inode;
293 };
294 
295 #define EROFS_I(ptr)	container_of(ptr, struct erofs_inode, vfs_inode)
296 
297 static inline erofs_off_t erofs_iloc(struct inode *inode)
298 {
299 	struct erofs_sb_info *sbi = EROFS_I_SB(inode);
300 
301 	return erofs_pos(inode->i_sb, sbi->meta_blkaddr) +
302 		(EROFS_I(inode)->nid << sbi->islotbits);
303 }
304 
305 static inline unsigned int erofs_inode_version(unsigned int ifmt)
306 {
307 	return (ifmt >> EROFS_I_VERSION_BIT) & EROFS_I_VERSION_MASK;
308 }
309 
310 static inline unsigned int erofs_inode_datalayout(unsigned int ifmt)
311 {
312 	return (ifmt >> EROFS_I_DATALAYOUT_BIT) & EROFS_I_DATALAYOUT_MASK;
313 }
314 
315 /*
316  * Different from grab_cache_page_nowait(), reclaiming is never triggered
317  * when allocating new pages.
318  */
319 static inline
320 struct page *erofs_grab_cache_page_nowait(struct address_space *mapping,
321 					  pgoff_t index)
322 {
323 	return pagecache_get_page(mapping, index,
324 			FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT,
325 			readahead_gfp_mask(mapping) & ~__GFP_RECLAIM);
326 }
327 
328 /* Has a disk mapping */
329 #define EROFS_MAP_MAPPED	0x0001
330 /* Located in metadata (could be copied from bd_inode) */
331 #define EROFS_MAP_META		0x0002
332 /* The extent is encoded */
333 #define EROFS_MAP_ENCODED	0x0004
334 /* The length of extent is full */
335 #define EROFS_MAP_FULL_MAPPED	0x0008
336 /* Located in the special packed inode */
337 #define EROFS_MAP_FRAGMENT	0x0010
338 /* The extent refers to partial decompressed data */
339 #define EROFS_MAP_PARTIAL_REF	0x0020
340 
341 struct erofs_map_blocks {
342 	struct erofs_buf buf;
343 
344 	erofs_off_t m_pa, m_la;
345 	u64 m_plen, m_llen;
346 
347 	unsigned short m_deviceid;
348 	char m_algorithmformat;
349 	unsigned int m_flags;
350 };
351 
352 /*
353  * Used to get the exact decompressed length, e.g. fiemap (consider lookback
354  * approach instead if possible since it's more metadata lightweight.)
355  */
356 #define EROFS_GET_BLOCKS_FIEMAP		0x0001
357 /* Used to map the whole extent if non-negligible data is requested for LZMA */
358 #define EROFS_GET_BLOCKS_READMORE	0x0002
359 /* Used to map tail extent for tailpacking inline or fragment pcluster */
360 #define EROFS_GET_BLOCKS_FINDTAIL	0x0004
361 
362 enum {
363 	Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX,
364 	Z_EROFS_COMPRESSION_INTERLACED,
365 	Z_EROFS_COMPRESSION_RUNTIME_MAX
366 };
367 
368 struct erofs_map_dev {
369 	struct erofs_fscache *m_fscache;
370 	struct block_device *m_bdev;
371 	struct dax_device *m_daxdev;
372 	u64 m_dax_part_off;
373 
374 	erofs_off_t m_pa;
375 	unsigned int m_deviceid;
376 };
377 
378 extern const struct super_operations erofs_sops;
379 
380 extern const struct address_space_operations erofs_raw_access_aops;
381 extern const struct address_space_operations z_erofs_aops;
382 extern const struct address_space_operations erofs_fscache_access_aops;
383 
384 extern const struct inode_operations erofs_generic_iops;
385 extern const struct inode_operations erofs_symlink_iops;
386 extern const struct inode_operations erofs_fast_symlink_iops;
387 extern const struct inode_operations erofs_dir_iops;
388 
389 extern const struct file_operations erofs_file_fops;
390 extern const struct file_operations erofs_dir_fops;
391 
392 extern const struct iomap_ops z_erofs_iomap_report_ops;
393 
394 /* flags for erofs_fscache_register_cookie() */
395 #define EROFS_REG_COOKIE_SHARE		0x0001
396 #define EROFS_REG_COOKIE_NEED_NOEXIST	0x0002
397 
398 void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf,
399 			  erofs_off_t *offset, int *lengthp);
400 void erofs_unmap_metabuf(struct erofs_buf *buf);
401 void erofs_put_metabuf(struct erofs_buf *buf);
402 void *erofs_bread(struct erofs_buf *buf, erofs_off_t offset,
403 		  enum erofs_kmap_type type);
404 void erofs_init_metabuf(struct erofs_buf *buf, struct super_block *sb);
405 void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,
406 			 erofs_off_t offset, enum erofs_kmap_type type);
407 int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *dev);
408 int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
409 		 u64 start, u64 len);
410 int erofs_map_blocks(struct inode *inode, struct erofs_map_blocks *map);
411 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid);
412 int erofs_getattr(struct mnt_idmap *idmap, const struct path *path,
413 		  struct kstat *stat, u32 request_mask,
414 		  unsigned int query_flags);
415 int erofs_namei(struct inode *dir, const struct qstr *name,
416 		erofs_nid_t *nid, unsigned int *d_type);
417 
418 static inline void *erofs_vm_map_ram(struct page **pages, unsigned int count)
419 {
420 	int retried = 0;
421 
422 	while (1) {
423 		void *p = vm_map_ram(pages, count, -1);
424 
425 		/* retry two more times (totally 3 times) */
426 		if (p || ++retried >= 3)
427 			return p;
428 		vm_unmap_aliases();
429 	}
430 	return NULL;
431 }
432 
433 int erofs_register_sysfs(struct super_block *sb);
434 void erofs_unregister_sysfs(struct super_block *sb);
435 int __init erofs_init_sysfs(void);
436 void erofs_exit_sysfs(void);
437 
438 struct page *__erofs_allocpage(struct page **pagepool, gfp_t gfp, bool tryrsv);
439 static inline struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp)
440 {
441 	return __erofs_allocpage(pagepool, gfp, false);
442 }
443 static inline void erofs_pagepool_add(struct page **pagepool, struct page *page)
444 {
445 	set_page_private(page, (unsigned long)*pagepool);
446 	*pagepool = page;
447 }
448 void erofs_release_pages(struct page **pagepool);
449 
450 #ifdef CONFIG_EROFS_FS_ZIP
451 void erofs_workgroup_put(struct erofs_workgroup *grp);
452 struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb,
453 					     pgoff_t index);
454 struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb,
455 					       struct erofs_workgroup *grp);
456 void erofs_workgroup_free_rcu(struct erofs_workgroup *grp);
457 void erofs_shrinker_register(struct super_block *sb);
458 void erofs_shrinker_unregister(struct super_block *sb);
459 int __init erofs_init_shrinker(void);
460 void erofs_exit_shrinker(void);
461 int __init z_erofs_init_zip_subsystem(void);
462 void z_erofs_exit_zip_subsystem(void);
463 int erofs_try_to_free_all_cached_folios(struct erofs_sb_info *sbi,
464 					struct erofs_workgroup *egrp);
465 int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map,
466 			    int flags);
467 void *z_erofs_get_gbuf(unsigned int requiredpages);
468 void z_erofs_put_gbuf(void *ptr);
469 int z_erofs_gbuf_growsize(unsigned int nrpages);
470 int __init z_erofs_gbuf_init(void);
471 void z_erofs_gbuf_exit(void);
472 int erofs_init_managed_cache(struct super_block *sb);
473 int z_erofs_parse_cfgs(struct super_block *sb, struct erofs_super_block *dsb);
474 #else
475 static inline void erofs_shrinker_register(struct super_block *sb) {}
476 static inline void erofs_shrinker_unregister(struct super_block *sb) {}
477 static inline int erofs_init_shrinker(void) { return 0; }
478 static inline void erofs_exit_shrinker(void) {}
479 static inline int z_erofs_init_zip_subsystem(void) { return 0; }
480 static inline void z_erofs_exit_zip_subsystem(void) {}
481 static inline int z_erofs_gbuf_init(void) { return 0; }
482 static inline void z_erofs_gbuf_exit(void) {}
483 static inline int erofs_init_managed_cache(struct super_block *sb) { return 0; }
484 #endif	/* !CONFIG_EROFS_FS_ZIP */
485 
486 #ifdef CONFIG_EROFS_FS_ZIP_LZMA
487 int __init z_erofs_lzma_init(void);
488 void z_erofs_lzma_exit(void);
489 #else
490 static inline int z_erofs_lzma_init(void) { return 0; }
491 static inline int z_erofs_lzma_exit(void) { return 0; }
492 #endif	/* !CONFIG_EROFS_FS_ZIP_LZMA */
493 
494 #ifdef CONFIG_EROFS_FS_ZIP_DEFLATE
495 int __init z_erofs_deflate_init(void);
496 void z_erofs_deflate_exit(void);
497 #else
498 static inline int z_erofs_deflate_init(void) { return 0; }
499 static inline int z_erofs_deflate_exit(void) { return 0; }
500 #endif	/* !CONFIG_EROFS_FS_ZIP_DEFLATE */
501 
502 #ifdef CONFIG_EROFS_FS_ZIP_ZSTD
503 int __init z_erofs_zstd_init(void);
504 void z_erofs_zstd_exit(void);
505 #else
506 static inline int z_erofs_zstd_init(void) { return 0; }
507 static inline int z_erofs_zstd_exit(void) { return 0; }
508 #endif	/* !CONFIG_EROFS_FS_ZIP_ZSTD */
509 
510 #ifdef CONFIG_EROFS_FS_ONDEMAND
511 int erofs_fscache_register_fs(struct super_block *sb);
512 void erofs_fscache_unregister_fs(struct super_block *sb);
513 
514 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
515 					char *name, unsigned int flags);
516 void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache);
517 struct bio *erofs_fscache_bio_alloc(struct erofs_map_dev *mdev);
518 void erofs_fscache_submit_bio(struct bio *bio);
519 #else
520 static inline int erofs_fscache_register_fs(struct super_block *sb)
521 {
522 	return -EOPNOTSUPP;
523 }
524 static inline void erofs_fscache_unregister_fs(struct super_block *sb) {}
525 
526 static inline
527 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
528 					char *name, unsigned int flags)
529 {
530 	return ERR_PTR(-EOPNOTSUPP);
531 }
532 
533 static inline void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache)
534 {
535 }
536 static inline struct bio *erofs_fscache_bio_alloc(struct erofs_map_dev *mdev) { return NULL; }
537 static inline void erofs_fscache_submit_bio(struct bio *bio) {}
538 #endif
539 
540 #define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */
541 
542 #endif	/* __EROFS_INTERNAL_H */
543