xref: /linux/fs/erofs/internal.h (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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 
38 typedef u64 erofs_nid_t;
39 typedef u64 erofs_off_t;
40 /* data type for filesystem-wide blocks number */
41 typedef u32 erofs_blk_t;
42 
43 struct erofs_device_info {
44 	char *path;
45 	struct erofs_fscache *fscache;
46 	struct file *file;
47 	struct dax_device *dax_dev;
48 	u64 dax_part_off;
49 
50 	u32 blocks;
51 	u32 mapped_blkaddr;
52 };
53 
54 enum {
55 	EROFS_SYNC_DECOMPRESS_AUTO,
56 	EROFS_SYNC_DECOMPRESS_FORCE_ON,
57 	EROFS_SYNC_DECOMPRESS_FORCE_OFF
58 };
59 
60 struct erofs_mount_opts {
61 	/* current strategy of how to use managed cache */
62 	unsigned char cache_strategy;
63 	/* strategy of sync decompression (0 - auto, 1 - force on, 2 - force off) */
64 	unsigned int sync_decompress;
65 	/* threshold for decompression synchronously */
66 	unsigned int max_sync_decompress_pages;
67 	unsigned int mount_opt;
68 };
69 
70 struct erofs_dev_context {
71 	struct idr tree;
72 	struct rw_semaphore rwsem;
73 
74 	unsigned int extra_devices;
75 	bool flatdev;
76 };
77 
78 /* all filesystem-wide lz4 configurations */
79 struct erofs_sb_lz4_info {
80 	/* # of pages needed for EROFS lz4 rolling decompression */
81 	u16 max_distance_pages;
82 	/* maximum possible blocks for pclusters in the filesystem */
83 	u16 max_pclusterblks;
84 };
85 
86 struct erofs_domain {
87 	refcount_t ref;
88 	struct list_head list;
89 	struct fscache_volume *volume;
90 	char *domain_id;
91 };
92 
93 struct erofs_fscache {
94 	struct fscache_cookie *cookie;
95 	struct inode *inode;	/* anonymous inode for the blob */
96 
97 	/* used for share domain mode */
98 	struct erofs_domain *domain;
99 	struct list_head node;
100 	refcount_t ref;
101 	char *name;
102 };
103 
104 struct erofs_xattr_prefix_item {
105 	struct erofs_xattr_long_prefix *prefix;
106 	u8 infix_len;
107 };
108 
109 struct erofs_sb_info {
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 file *fdev;
128 	struct inode *packed_inode;
129 	struct erofs_dev_context *devs;
130 	struct dax_device *dax_dev;
131 	u64 dax_part_off;
132 	u64 total_blocks;
133 	u32 primarydevice_blocks;
134 
135 	u32 meta_blkaddr;
136 #ifdef CONFIG_EROFS_FS_XATTR
137 	u32 xattr_blkaddr;
138 	u32 xattr_prefix_start;
139 	u8 xattr_prefix_count;
140 	struct erofs_xattr_prefix_item *xattr_prefixes;
141 	unsigned int xattr_filter_reserved;
142 #endif
143 	u16 device_id_mask;	/* valid bits of device id to be used */
144 
145 	unsigned char islotbits;	/* inode slot unit size in bit shift */
146 	unsigned char blkszbits;	/* filesystem block size in bit shift */
147 
148 	u32 sb_size;			/* total superblock size */
149 	u32 build_time_nsec;
150 	u64 build_time;
151 
152 	/* what we really care is nid, rather than ino.. */
153 	erofs_nid_t root_nid;
154 	erofs_nid_t packed_nid;
155 	/* used for statfs, f_files - f_favail */
156 	u64 inos;
157 
158 	u8 uuid[16];                    /* 128-bit uuid for volume */
159 	u8 volume_name[16];             /* volume name */
160 	u32 feature_compat;
161 	u32 feature_incompat;
162 
163 	/* sysfs support */
164 	struct kobject s_kobj;		/* /sys/fs/erofs/<devname> */
165 	struct completion s_kobj_unregister;
166 
167 	/* fscache support */
168 	struct fscache_volume *volume;
169 	struct erofs_fscache *s_fscache;
170 	struct erofs_domain *domain;
171 	char *fsid;
172 	char *domain_id;
173 };
174 
175 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
176 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)
177 
178 /* Mount flags set via mount options or defaults */
179 #define EROFS_MOUNT_XATTR_USER		0x00000010
180 #define EROFS_MOUNT_POSIX_ACL		0x00000020
181 #define EROFS_MOUNT_DAX_ALWAYS		0x00000040
182 #define EROFS_MOUNT_DAX_NEVER		0x00000080
183 
184 #define clear_opt(opt, option)	((opt)->mount_opt &= ~EROFS_MOUNT_##option)
185 #define set_opt(opt, option)	((opt)->mount_opt |= EROFS_MOUNT_##option)
186 #define test_opt(opt, option)	((opt)->mount_opt & EROFS_MOUNT_##option)
187 
188 static inline bool erofs_is_fileio_mode(struct erofs_sb_info *sbi)
189 {
190 	return IS_ENABLED(CONFIG_EROFS_FS_BACKED_BY_FILE) && sbi->fdev;
191 }
192 
193 static inline bool erofs_is_fscache_mode(struct super_block *sb)
194 {
195 	return IS_ENABLED(CONFIG_EROFS_FS_ONDEMAND) &&
196 			!erofs_is_fileio_mode(EROFS_SB(sb)) && !sb->s_bdev;
197 }
198 
199 enum {
200 	EROFS_ZIP_CACHE_DISABLED,
201 	EROFS_ZIP_CACHE_READAHEAD,
202 	EROFS_ZIP_CACHE_READAROUND
203 };
204 
205 enum erofs_kmap_type {
206 	EROFS_NO_KMAP,		/* don't map the buffer */
207 	EROFS_KMAP,		/* use kmap_local_page() to map the buffer */
208 };
209 
210 struct erofs_buf {
211 	struct address_space *mapping;
212 	struct file *file;
213 	struct page *page;
214 	void *base;
215 };
216 #define __EROFS_BUF_INITIALIZER	((struct erofs_buf){ .page = NULL })
217 
218 #define erofs_blknr(sb, addr)	((erofs_blk_t)((addr) >> (sb)->s_blocksize_bits))
219 #define erofs_blkoff(sb, addr)	((addr) & ((sb)->s_blocksize - 1))
220 #define erofs_pos(sb, blk)	((erofs_off_t)(blk) << (sb)->s_blocksize_bits)
221 #define erofs_iblks(i)	(round_up((i)->i_size, i_blocksize(i)) >> (i)->i_blkbits)
222 
223 #define EROFS_FEATURE_FUNCS(name, compat, feature) \
224 static inline bool erofs_sb_has_##name(struct erofs_sb_info *sbi) \
225 { \
226 	return sbi->feature_##compat & EROFS_FEATURE_##feature; \
227 }
228 
229 EROFS_FEATURE_FUNCS(zero_padding, incompat, INCOMPAT_ZERO_PADDING)
230 EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS)
231 EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER)
232 EROFS_FEATURE_FUNCS(chunked_file, incompat, INCOMPAT_CHUNKED_FILE)
233 EROFS_FEATURE_FUNCS(device_table, incompat, INCOMPAT_DEVICE_TABLE)
234 EROFS_FEATURE_FUNCS(compr_head2, incompat, INCOMPAT_COMPR_HEAD2)
235 EROFS_FEATURE_FUNCS(ztailpacking, incompat, INCOMPAT_ZTAILPACKING)
236 EROFS_FEATURE_FUNCS(fragments, incompat, INCOMPAT_FRAGMENTS)
237 EROFS_FEATURE_FUNCS(dedupe, incompat, INCOMPAT_DEDUPE)
238 EROFS_FEATURE_FUNCS(xattr_prefixes, incompat, INCOMPAT_XATTR_PREFIXES)
239 EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
240 EROFS_FEATURE_FUNCS(xattr_filter, compat, COMPAT_XATTR_FILTER)
241 
242 /* atomic flag definitions */
243 #define EROFS_I_EA_INITED_BIT	0
244 #define EROFS_I_Z_INITED_BIT	1
245 
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)
249 
250 struct erofs_inode {
251 	erofs_nid_t nid;
252 
253 	/* atomic flags (including bitlocks) */
254 	unsigned long flags;
255 
256 	unsigned char datalayout;
257 	unsigned char inode_isize;
258 	unsigned int xattr_isize;
259 
260 	unsigned int xattr_name_filter;
261 	unsigned int xattr_shared_count;
262 	unsigned int *xattr_shared_xattrs;
263 
264 	union {
265 		erofs_blk_t raw_blkaddr;
266 		struct {
267 			unsigned short	chunkformat;
268 			unsigned char	chunkbits;
269 		};
270 #ifdef CONFIG_EROFS_FS_ZIP
271 		struct {
272 			unsigned short z_advise;
273 			unsigned char  z_algorithmtype[2];
274 			unsigned char  z_logical_clusterbits;
275 			unsigned long  z_tailextent_headlcn;
276 			union {
277 				struct {
278 					erofs_off_t    z_idataoff;
279 					unsigned short z_idata_size;
280 				};
281 				erofs_off_t z_fragmentoff;
282 			};
283 		};
284 #endif	/* CONFIG_EROFS_FS_ZIP */
285 	};
286 	/* the corresponding vfs inode */
287 	struct inode vfs_inode;
288 };
289 
290 #define EROFS_I(ptr)	container_of(ptr, struct erofs_inode, vfs_inode)
291 
292 static inline erofs_off_t erofs_iloc(struct inode *inode)
293 {
294 	struct erofs_sb_info *sbi = EROFS_I_SB(inode);
295 
296 	return erofs_pos(inode->i_sb, sbi->meta_blkaddr) +
297 		(EROFS_I(inode)->nid << sbi->islotbits);
298 }
299 
300 static inline unsigned int erofs_inode_version(unsigned int ifmt)
301 {
302 	return (ifmt >> EROFS_I_VERSION_BIT) & EROFS_I_VERSION_MASK;
303 }
304 
305 static inline unsigned int erofs_inode_datalayout(unsigned int ifmt)
306 {
307 	return (ifmt >> EROFS_I_DATALAYOUT_BIT) & EROFS_I_DATALAYOUT_MASK;
308 }
309 
310 /* reclaiming is never triggered when allocating new folios. */
311 static inline struct folio *erofs_grab_folio_nowait(struct address_space *as,
312 						    pgoff_t index)
313 {
314 	return __filemap_get_folio(as, index,
315 			FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT,
316 			readahead_gfp_mask(as) & ~__GFP_RECLAIM);
317 }
318 
319 /* Has a disk mapping */
320 #define EROFS_MAP_MAPPED	0x0001
321 /* Located in metadata (could be copied from bd_inode) */
322 #define EROFS_MAP_META		0x0002
323 /* The extent is encoded */
324 #define EROFS_MAP_ENCODED	0x0004
325 /* The length of extent is full */
326 #define EROFS_MAP_FULL_MAPPED	0x0008
327 /* Located in the special packed inode */
328 #define EROFS_MAP_FRAGMENT	0x0010
329 /* The extent refers to partial decompressed data */
330 #define EROFS_MAP_PARTIAL_REF	0x0020
331 
332 struct erofs_map_blocks {
333 	struct erofs_buf buf;
334 
335 	erofs_off_t m_pa, m_la;
336 	u64 m_plen, m_llen;
337 
338 	unsigned short m_deviceid;
339 	char m_algorithmformat;
340 	unsigned int m_flags;
341 };
342 
343 /*
344  * Used to get the exact decompressed length, e.g. fiemap (consider lookback
345  * approach instead if possible since it's more metadata lightweight.)
346  */
347 #define EROFS_GET_BLOCKS_FIEMAP		0x0001
348 /* Used to map the whole extent if non-negligible data is requested for LZMA */
349 #define EROFS_GET_BLOCKS_READMORE	0x0002
350 /* Used to map tail extent for tailpacking inline or fragment pcluster */
351 #define EROFS_GET_BLOCKS_FINDTAIL	0x0004
352 
353 enum {
354 	Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX,
355 	Z_EROFS_COMPRESSION_INTERLACED,
356 	Z_EROFS_COMPRESSION_RUNTIME_MAX
357 };
358 
359 struct erofs_map_dev {
360 	struct erofs_fscache *m_fscache;
361 	struct block_device *m_bdev;
362 	struct dax_device *m_daxdev;
363 	struct file *m_fp;
364 	u64 m_dax_part_off;
365 
366 	erofs_off_t m_pa;
367 	unsigned int m_deviceid;
368 };
369 
370 extern const struct super_operations erofs_sops;
371 
372 extern const struct address_space_operations erofs_aops;
373 extern const struct address_space_operations erofs_fileio_aops;
374 extern const struct address_space_operations z_erofs_aops;
375 extern const struct address_space_operations erofs_fscache_access_aops;
376 
377 extern const struct inode_operations erofs_generic_iops;
378 extern const struct inode_operations erofs_symlink_iops;
379 extern const struct inode_operations erofs_fast_symlink_iops;
380 extern const struct inode_operations erofs_dir_iops;
381 
382 extern const struct file_operations erofs_file_fops;
383 extern const struct file_operations erofs_dir_fops;
384 
385 extern const struct iomap_ops z_erofs_iomap_report_ops;
386 
387 /* flags for erofs_fscache_register_cookie() */
388 #define EROFS_REG_COOKIE_SHARE		0x0001
389 #define EROFS_REG_COOKIE_NEED_NOEXIST	0x0002
390 
391 void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf,
392 			  erofs_off_t *offset, int *lengthp);
393 void erofs_unmap_metabuf(struct erofs_buf *buf);
394 void erofs_put_metabuf(struct erofs_buf *buf);
395 void *erofs_bread(struct erofs_buf *buf, erofs_off_t offset,
396 		  enum erofs_kmap_type type);
397 void erofs_init_metabuf(struct erofs_buf *buf, struct super_block *sb);
398 void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,
399 			 erofs_off_t offset, enum erofs_kmap_type type);
400 int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *dev);
401 int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
402 		 u64 start, u64 len);
403 int erofs_map_blocks(struct inode *inode, struct erofs_map_blocks *map);
404 void erofs_onlinefolio_init(struct folio *folio);
405 void erofs_onlinefolio_split(struct folio *folio);
406 void erofs_onlinefolio_end(struct folio *folio, int err);
407 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid);
408 int erofs_getattr(struct mnt_idmap *idmap, const struct path *path,
409 		  struct kstat *stat, u32 request_mask,
410 		  unsigned int query_flags);
411 int erofs_namei(struct inode *dir, const struct qstr *name,
412 		erofs_nid_t *nid, unsigned int *d_type);
413 
414 static inline void *erofs_vm_map_ram(struct page **pages, unsigned int count)
415 {
416 	int retried = 0;
417 
418 	while (1) {
419 		void *p = vm_map_ram(pages, count, -1);
420 
421 		/* retry two more times (totally 3 times) */
422 		if (p || ++retried >= 3)
423 			return p;
424 		vm_unmap_aliases();
425 	}
426 	return NULL;
427 }
428 
429 int erofs_register_sysfs(struct super_block *sb);
430 void erofs_unregister_sysfs(struct super_block *sb);
431 int __init erofs_init_sysfs(void);
432 void erofs_exit_sysfs(void);
433 
434 struct page *__erofs_allocpage(struct page **pagepool, gfp_t gfp, bool tryrsv);
435 static inline struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp)
436 {
437 	return __erofs_allocpage(pagepool, gfp, false);
438 }
439 static inline void erofs_pagepool_add(struct page **pagepool, struct page *page)
440 {
441 	set_page_private(page, (unsigned long)*pagepool);
442 	*pagepool = page;
443 }
444 void erofs_release_pages(struct page **pagepool);
445 
446 #ifdef CONFIG_EROFS_FS_ZIP
447 #define MNGD_MAPPING(sbi)	((sbi)->managed_cache->i_mapping)
448 
449 extern atomic_long_t erofs_global_shrink_cnt;
450 void erofs_shrinker_register(struct super_block *sb);
451 void erofs_shrinker_unregister(struct super_block *sb);
452 int __init erofs_init_shrinker(void);
453 void erofs_exit_shrinker(void);
454 int __init z_erofs_init_subsystem(void);
455 void z_erofs_exit_subsystem(void);
456 unsigned long z_erofs_shrink_scan(struct erofs_sb_info *sbi,
457 				  unsigned long nr_shrink);
458 int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map,
459 			    int flags);
460 void *z_erofs_get_gbuf(unsigned int requiredpages);
461 void z_erofs_put_gbuf(void *ptr);
462 int z_erofs_gbuf_growsize(unsigned int nrpages);
463 int __init z_erofs_gbuf_init(void);
464 void z_erofs_gbuf_exit(void);
465 int erofs_init_managed_cache(struct super_block *sb);
466 int z_erofs_parse_cfgs(struct super_block *sb, struct erofs_super_block *dsb);
467 #else
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_subsystem(void) { return 0; }
473 static inline void z_erofs_exit_subsystem(void) {}
474 static inline int erofs_init_managed_cache(struct super_block *sb) { return 0; }
475 #endif	/* !CONFIG_EROFS_FS_ZIP */
476 
477 #ifdef CONFIG_EROFS_FS_BACKED_BY_FILE
478 struct bio *erofs_fileio_bio_alloc(struct erofs_map_dev *mdev);
479 void erofs_fileio_submit_bio(struct bio *bio);
480 #else
481 static inline struct bio *erofs_fileio_bio_alloc(struct erofs_map_dev *mdev) { return NULL; }
482 static inline void erofs_fileio_submit_bio(struct bio *bio) {}
483 #endif
484 
485 #ifdef CONFIG_EROFS_FS_ONDEMAND
486 int erofs_fscache_register_fs(struct super_block *sb);
487 void erofs_fscache_unregister_fs(struct super_block *sb);
488 
489 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
490 					char *name, unsigned int flags);
491 void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache);
492 struct bio *erofs_fscache_bio_alloc(struct erofs_map_dev *mdev);
493 void erofs_fscache_submit_bio(struct bio *bio);
494 #else
495 static inline int erofs_fscache_register_fs(struct super_block *sb)
496 {
497 	return -EOPNOTSUPP;
498 }
499 static inline void erofs_fscache_unregister_fs(struct super_block *sb) {}
500 
501 static inline
502 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
503 					char *name, unsigned int flags)
504 {
505 	return ERR_PTR(-EOPNOTSUPP);
506 }
507 
508 static inline void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache)
509 {
510 }
511 static inline struct bio *erofs_fscache_bio_alloc(struct erofs_map_dev *mdev) { return NULL; }
512 static inline void erofs_fscache_submit_bio(struct bio *bio) {}
513 #endif
514 
515 #define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */
516 
517 #endif	/* __EROFS_INTERNAL_H */
518