xref: /openbmc/linux/fs/erofs/internal.h (revision 5085e036)
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/dcache.h>
12 #include <linux/mm.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>
20 #include "erofs_fs.h"
21 
22 /* redefine pr_fmt "erofs: " */
23 #undef pr_fmt
24 #define pr_fmt(fmt) "erofs: " fmt
25 
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
37 #else
38 #define erofs_dbg(x, ...)       ((void)0)
39 #define DBG_BUGON(x)            ((void)(x))
40 #endif	/* !CONFIG_EROFS_FS_DEBUG */
41 
42 /* EROFS_SUPER_MAGIC_V1 to represent the whole file system */
43 #define EROFS_SUPER_MAGIC   EROFS_SUPER_MAGIC_V1
44 
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;
49 
50 struct erofs_device_info {
51 	char *path;
52 	struct erofs_fscache *fscache;
53 	struct block_device *bdev;
54 	struct dax_device *dax_dev;
55 	u64 dax_part_off;
56 
57 	u32 blocks;
58 	u32 mapped_blkaddr;
59 };
60 
61 enum {
62 	EROFS_SYNC_DECOMPRESS_AUTO,
63 	EROFS_SYNC_DECOMPRESS_FORCE_ON,
64 	EROFS_SYNC_DECOMPRESS_FORCE_OFF
65 };
66 
67 struct erofs_mount_opts {
68 #ifdef CONFIG_EROFS_FS_ZIP
69 	/* current strategy of how to use managed cache */
70 	unsigned char cache_strategy;
71 	/* strategy of sync decompression (0 - auto, 1 - force on, 2 - force off) */
72 	unsigned int sync_decompress;
73 
74 	/* threshold for decompression synchronously */
75 	unsigned int max_sync_decompress_pages;
76 #endif
77 	unsigned int mount_opt;
78 	char *fsid;
79 };
80 
81 struct erofs_dev_context {
82 	struct idr tree;
83 	struct rw_semaphore rwsem;
84 
85 	unsigned int extra_devices;
86 };
87 
88 struct erofs_fs_context {
89 	struct erofs_mount_opts opt;
90 	struct erofs_dev_context *devs;
91 };
92 
93 /* all filesystem-wide lz4 configurations */
94 struct erofs_sb_lz4_info {
95 	/* # of pages needed for EROFS lz4 rolling decompression */
96 	u16 max_distance_pages;
97 	/* maximum possible blocks for pclusters in the filesystem */
98 	u16 max_pclusterblks;
99 };
100 
101 struct erofs_fscache {
102 	struct fscache_cookie *cookie;
103 	struct inode *inode;
104 };
105 
106 struct erofs_sb_info {
107 	struct erofs_mount_opts opt;	/* options */
108 #ifdef CONFIG_EROFS_FS_ZIP
109 	/* list for all registered superblocks, mainly for shrinker */
110 	struct list_head list;
111 	struct mutex umount_mutex;
112 
113 	/* managed XArray arranged in physical block number */
114 	struct xarray managed_pslots;
115 
116 	unsigned int shrinker_run_no;
117 	u16 available_compr_algs;
118 
119 	/* pseudo inode to manage cached pages */
120 	struct inode *managed_cache;
121 
122 	struct erofs_sb_lz4_info lz4;
123 #endif	/* CONFIG_EROFS_FS_ZIP */
124 	struct erofs_dev_context *devs;
125 	struct dax_device *dax_dev;
126 	u64 dax_part_off;
127 	u64 total_blocks;
128 	u32 primarydevice_blocks;
129 
130 	u32 meta_blkaddr;
131 #ifdef CONFIG_EROFS_FS_XATTR
132 	u32 xattr_blkaddr;
133 #endif
134 	u16 device_id_mask;	/* valid bits of device id to be used */
135 
136 	/* inode slot unit size in bit shift */
137 	unsigned char islotbits;
138 
139 	u32 sb_size;			/* total superblock size */
140 	u32 build_time_nsec;
141 	u64 build_time;
142 
143 	/* what we really care is nid, rather than ino.. */
144 	erofs_nid_t root_nid;
145 	/* used for statfs, f_files - f_favail */
146 	u64 inos;
147 
148 	u8 uuid[16];                    /* 128-bit uuid for volume */
149 	u8 volume_name[16];             /* volume name */
150 	u32 feature_compat;
151 	u32 feature_incompat;
152 
153 	/* sysfs support */
154 	struct kobject s_kobj;		/* /sys/fs/erofs/<devname> */
155 	struct completion s_kobj_unregister;
156 
157 	/* fscache support */
158 	struct fscache_volume *volume;
159 	struct erofs_fscache *s_fscache;
160 };
161 
162 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
163 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)
164 
165 /* Mount flags set via mount options or defaults */
166 #define EROFS_MOUNT_XATTR_USER		0x00000010
167 #define EROFS_MOUNT_POSIX_ACL		0x00000020
168 #define EROFS_MOUNT_DAX_ALWAYS		0x00000040
169 #define EROFS_MOUNT_DAX_NEVER		0x00000080
170 
171 #define clear_opt(opt, option)	((opt)->mount_opt &= ~EROFS_MOUNT_##option)
172 #define set_opt(opt, option)	((opt)->mount_opt |= EROFS_MOUNT_##option)
173 #define test_opt(opt, option)	((opt)->mount_opt & EROFS_MOUNT_##option)
174 
175 static inline bool erofs_is_fscache_mode(struct super_block *sb)
176 {
177 	return IS_ENABLED(CONFIG_EROFS_FS_ONDEMAND) && !sb->s_bdev;
178 }
179 
180 enum {
181 	EROFS_ZIP_CACHE_DISABLED,
182 	EROFS_ZIP_CACHE_READAHEAD,
183 	EROFS_ZIP_CACHE_READAROUND
184 };
185 
186 #ifdef CONFIG_EROFS_FS_ZIP
187 #define EROFS_LOCKED_MAGIC     (INT_MIN | 0xE0F510CCL)
188 
189 /* basic unit of the workstation of a super_block */
190 struct erofs_workgroup {
191 	/* the workgroup index in the workstation */
192 	pgoff_t index;
193 
194 	/* overall workgroup reference count */
195 	atomic_t refcount;
196 };
197 
198 #if defined(CONFIG_SMP)
199 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
200 						 int val)
201 {
202 	preempt_disable();
203 	if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) {
204 		preempt_enable();
205 		return false;
206 	}
207 	return true;
208 }
209 
210 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
211 					    int orig_val)
212 {
213 	/*
214 	 * other observers should notice all modifications
215 	 * in the freezing period.
216 	 */
217 	smp_mb();
218 	atomic_set(&grp->refcount, orig_val);
219 	preempt_enable();
220 }
221 
222 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
223 {
224 	return atomic_cond_read_relaxed(&grp->refcount,
225 					VAL != EROFS_LOCKED_MAGIC);
226 }
227 #else
228 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
229 						 int val)
230 {
231 	preempt_disable();
232 	/* no need to spin on UP platforms, let's just disable preemption. */
233 	if (val != atomic_read(&grp->refcount)) {
234 		preempt_enable();
235 		return false;
236 	}
237 	return true;
238 }
239 
240 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
241 					    int orig_val)
242 {
243 	preempt_enable();
244 }
245 
246 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
247 {
248 	int v = atomic_read(&grp->refcount);
249 
250 	/* workgroup is never freezed on uniprocessor systems */
251 	DBG_BUGON(v == EROFS_LOCKED_MAGIC);
252 	return v;
253 }
254 #endif	/* !CONFIG_SMP */
255 #endif	/* !CONFIG_EROFS_FS_ZIP */
256 
257 /* we strictly follow PAGE_SIZE and no buffer head yet */
258 #define LOG_BLOCK_SIZE		PAGE_SHIFT
259 
260 #undef LOG_SECTORS_PER_BLOCK
261 #define LOG_SECTORS_PER_BLOCK	(PAGE_SHIFT - 9)
262 
263 #undef SECTORS_PER_BLOCK
264 #define SECTORS_PER_BLOCK	(1 << SECTORS_PER_BLOCK)
265 
266 #define EROFS_BLKSIZ		(1 << LOG_BLOCK_SIZE)
267 
268 #if (EROFS_BLKSIZ % 4096 || !EROFS_BLKSIZ)
269 #error erofs cannot be used in this platform
270 #endif
271 
272 enum erofs_kmap_type {
273 	EROFS_NO_KMAP,		/* don't map the buffer */
274 	EROFS_KMAP,		/* use kmap() to map the buffer */
275 	EROFS_KMAP_ATOMIC,	/* use kmap_atomic() to map the buffer */
276 };
277 
278 struct erofs_buf {
279 	struct page *page;
280 	void *base;
281 	enum erofs_kmap_type kmap_type;
282 };
283 #define __EROFS_BUF_INITIALIZER	((struct erofs_buf){ .page = NULL })
284 
285 #define ROOT_NID(sb)		((sb)->root_nid)
286 
287 #define erofs_blknr(addr)       ((addr) / EROFS_BLKSIZ)
288 #define erofs_blkoff(addr)      ((addr) % EROFS_BLKSIZ)
289 #define blknr_to_addr(nr)       ((erofs_off_t)(nr) * EROFS_BLKSIZ)
290 
291 static inline erofs_off_t iloc(struct erofs_sb_info *sbi, erofs_nid_t nid)
292 {
293 	return blknr_to_addr(sbi->meta_blkaddr) + (nid << sbi->islotbits);
294 }
295 
296 #define EROFS_FEATURE_FUNCS(name, compat, feature) \
297 static inline bool erofs_sb_has_##name(struct erofs_sb_info *sbi) \
298 { \
299 	return sbi->feature_##compat & EROFS_FEATURE_##feature; \
300 }
301 
302 EROFS_FEATURE_FUNCS(zero_padding, incompat, INCOMPAT_ZERO_PADDING)
303 EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS)
304 EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER)
305 EROFS_FEATURE_FUNCS(chunked_file, incompat, INCOMPAT_CHUNKED_FILE)
306 EROFS_FEATURE_FUNCS(device_table, incompat, INCOMPAT_DEVICE_TABLE)
307 EROFS_FEATURE_FUNCS(compr_head2, incompat, INCOMPAT_COMPR_HEAD2)
308 EROFS_FEATURE_FUNCS(ztailpacking, incompat, INCOMPAT_ZTAILPACKING)
309 EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
310 
311 /* atomic flag definitions */
312 #define EROFS_I_EA_INITED_BIT	0
313 #define EROFS_I_Z_INITED_BIT	1
314 
315 /* bitlock definitions (arranged in reverse order) */
316 #define EROFS_I_BL_XATTR_BIT	(BITS_PER_LONG - 1)
317 #define EROFS_I_BL_Z_BIT	(BITS_PER_LONG - 2)
318 
319 struct erofs_inode {
320 	erofs_nid_t nid;
321 
322 	/* atomic flags (including bitlocks) */
323 	unsigned long flags;
324 
325 	unsigned char datalayout;
326 	unsigned char inode_isize;
327 	unsigned short xattr_isize;
328 
329 	unsigned int xattr_shared_count;
330 	unsigned int *xattr_shared_xattrs;
331 
332 	union {
333 		erofs_blk_t raw_blkaddr;
334 		struct {
335 			unsigned short	chunkformat;
336 			unsigned char	chunkbits;
337 		};
338 #ifdef CONFIG_EROFS_FS_ZIP
339 		struct {
340 			unsigned short z_advise;
341 			unsigned char  z_algorithmtype[2];
342 			unsigned char  z_logical_clusterbits;
343 			unsigned long  z_tailextent_headlcn;
344 			erofs_off_t    z_idataoff;
345 			unsigned short z_idata_size;
346 		};
347 #endif	/* CONFIG_EROFS_FS_ZIP */
348 	};
349 	/* the corresponding vfs inode */
350 	struct inode vfs_inode;
351 };
352 
353 #define EROFS_I(ptr)	\
354 	container_of(ptr, struct erofs_inode, vfs_inode)
355 
356 static inline unsigned long erofs_inode_datablocks(struct inode *inode)
357 {
358 	/* since i_size cannot be changed */
359 	return DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ);
360 }
361 
362 static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit,
363 					  unsigned int bits)
364 {
365 
366 	return (value >> bit) & ((1 << bits) - 1);
367 }
368 
369 
370 static inline unsigned int erofs_inode_version(unsigned int value)
371 {
372 	return erofs_bitrange(value, EROFS_I_VERSION_BIT,
373 			      EROFS_I_VERSION_BITS);
374 }
375 
376 static inline unsigned int erofs_inode_datalayout(unsigned int value)
377 {
378 	return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT,
379 			      EROFS_I_DATALAYOUT_BITS);
380 }
381 
382 /*
383  * Different from grab_cache_page_nowait(), reclaiming is never triggered
384  * when allocating new pages.
385  */
386 static inline
387 struct page *erofs_grab_cache_page_nowait(struct address_space *mapping,
388 					  pgoff_t index)
389 {
390 	return pagecache_get_page(mapping, index,
391 			FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT,
392 			readahead_gfp_mask(mapping) & ~__GFP_RECLAIM);
393 }
394 
395 extern const struct super_operations erofs_sops;
396 
397 extern const struct address_space_operations erofs_raw_access_aops;
398 extern const struct address_space_operations z_erofs_aops;
399 
400 enum {
401 	BH_Encoded = BH_PrivateStart,
402 	BH_FullMapped,
403 };
404 
405 /* Has a disk mapping */
406 #define EROFS_MAP_MAPPED	(1 << BH_Mapped)
407 /* Located in metadata (could be copied from bd_inode) */
408 #define EROFS_MAP_META		(1 << BH_Meta)
409 /* The extent is encoded */
410 #define EROFS_MAP_ENCODED	(1 << BH_Encoded)
411 /* The length of extent is full */
412 #define EROFS_MAP_FULL_MAPPED	(1 << BH_FullMapped)
413 
414 struct erofs_map_blocks {
415 	struct erofs_buf buf;
416 
417 	erofs_off_t m_pa, m_la;
418 	u64 m_plen, m_llen;
419 
420 	unsigned short m_deviceid;
421 	char m_algorithmformat;
422 	unsigned int m_flags;
423 };
424 
425 /* Flags used by erofs_map_blocks_flatmode() */
426 #define EROFS_GET_BLOCKS_RAW    0x0001
427 /*
428  * Used to get the exact decompressed length, e.g. fiemap (consider lookback
429  * approach instead if possible since it's more metadata lightweight.)
430  */
431 #define EROFS_GET_BLOCKS_FIEMAP	0x0002
432 /* Used to map the whole extent if non-negligible data is requested for LZMA */
433 #define EROFS_GET_BLOCKS_READMORE	0x0004
434 /* Used to map tail extent for tailpacking inline pcluster */
435 #define EROFS_GET_BLOCKS_FINDTAIL	0x0008
436 
437 enum {
438 	Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX,
439 	Z_EROFS_COMPRESSION_RUNTIME_MAX
440 };
441 
442 /* zmap.c */
443 extern const struct iomap_ops z_erofs_iomap_report_ops;
444 
445 #ifdef CONFIG_EROFS_FS_ZIP
446 int z_erofs_fill_inode(struct inode *inode);
447 int z_erofs_map_blocks_iter(struct inode *inode,
448 			    struct erofs_map_blocks *map,
449 			    int flags);
450 #else
451 static inline int z_erofs_fill_inode(struct inode *inode) { return -EOPNOTSUPP; }
452 static inline int z_erofs_map_blocks_iter(struct inode *inode,
453 					  struct erofs_map_blocks *map,
454 					  int flags)
455 {
456 	return -EOPNOTSUPP;
457 }
458 #endif	/* !CONFIG_EROFS_FS_ZIP */
459 
460 struct erofs_map_dev {
461 	struct erofs_fscache *m_fscache;
462 	struct block_device *m_bdev;
463 	struct dax_device *m_daxdev;
464 	u64 m_dax_part_off;
465 
466 	erofs_off_t m_pa;
467 	unsigned int m_deviceid;
468 };
469 
470 /* data.c */
471 extern const struct file_operations erofs_file_fops;
472 void erofs_unmap_metabuf(struct erofs_buf *buf);
473 void erofs_put_metabuf(struct erofs_buf *buf);
474 void *erofs_bread(struct erofs_buf *buf, struct inode *inode,
475 		  erofs_blk_t blkaddr, enum erofs_kmap_type type);
476 void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,
477 			 erofs_blk_t blkaddr, enum erofs_kmap_type type);
478 int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *dev);
479 int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
480 		 u64 start, u64 len);
481 int erofs_map_blocks(struct inode *inode,
482 		     struct erofs_map_blocks *map, int flags);
483 
484 /* inode.c */
485 static inline unsigned long erofs_inode_hash(erofs_nid_t nid)
486 {
487 #if BITS_PER_LONG == 32
488 	return (nid >> 32) ^ (nid & 0xffffffff);
489 #else
490 	return nid;
491 #endif
492 }
493 
494 extern const struct inode_operations erofs_generic_iops;
495 extern const struct inode_operations erofs_symlink_iops;
496 extern const struct inode_operations erofs_fast_symlink_iops;
497 
498 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid, bool dir);
499 int erofs_getattr(struct user_namespace *mnt_userns, const struct path *path,
500 		  struct kstat *stat, u32 request_mask,
501 		  unsigned int query_flags);
502 
503 /* namei.c */
504 extern const struct inode_operations erofs_dir_iops;
505 
506 int erofs_namei(struct inode *dir, const struct qstr *name,
507 		erofs_nid_t *nid, unsigned int *d_type);
508 
509 /* dir.c */
510 extern const struct file_operations erofs_dir_fops;
511 
512 static inline void *erofs_vm_map_ram(struct page **pages, unsigned int count)
513 {
514 	int retried = 0;
515 
516 	while (1) {
517 		void *p = vm_map_ram(pages, count, -1);
518 
519 		/* retry two more times (totally 3 times) */
520 		if (p || ++retried >= 3)
521 			return p;
522 		vm_unmap_aliases();
523 	}
524 	return NULL;
525 }
526 
527 /* pcpubuf.c */
528 void *erofs_get_pcpubuf(unsigned int requiredpages);
529 void erofs_put_pcpubuf(void *ptr);
530 int erofs_pcpubuf_growsize(unsigned int nrpages);
531 void erofs_pcpubuf_init(void);
532 void erofs_pcpubuf_exit(void);
533 
534 /* sysfs.c */
535 int erofs_register_sysfs(struct super_block *sb);
536 void erofs_unregister_sysfs(struct super_block *sb);
537 int __init erofs_init_sysfs(void);
538 void erofs_exit_sysfs(void);
539 
540 /* utils.c / zdata.c */
541 struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp);
542 static inline void erofs_pagepool_add(struct page **pagepool,
543 		struct page *page)
544 {
545 	set_page_private(page, (unsigned long)*pagepool);
546 	*pagepool = page;
547 }
548 void erofs_release_pages(struct page **pagepool);
549 
550 #ifdef CONFIG_EROFS_FS_ZIP
551 int erofs_workgroup_put(struct erofs_workgroup *grp);
552 struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb,
553 					     pgoff_t index);
554 struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb,
555 					       struct erofs_workgroup *grp);
556 void erofs_workgroup_free_rcu(struct erofs_workgroup *grp);
557 void erofs_shrinker_register(struct super_block *sb);
558 void erofs_shrinker_unregister(struct super_block *sb);
559 int __init erofs_init_shrinker(void);
560 void erofs_exit_shrinker(void);
561 int __init z_erofs_init_zip_subsystem(void);
562 void z_erofs_exit_zip_subsystem(void);
563 int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
564 				       struct erofs_workgroup *egrp);
565 int erofs_try_to_free_cached_page(struct page *page);
566 int z_erofs_load_lz4_config(struct super_block *sb,
567 			    struct erofs_super_block *dsb,
568 			    struct z_erofs_lz4_cfgs *lz4, int len);
569 #else
570 static inline void erofs_shrinker_register(struct super_block *sb) {}
571 static inline void erofs_shrinker_unregister(struct super_block *sb) {}
572 static inline int erofs_init_shrinker(void) { return 0; }
573 static inline void erofs_exit_shrinker(void) {}
574 static inline int z_erofs_init_zip_subsystem(void) { return 0; }
575 static inline void z_erofs_exit_zip_subsystem(void) {}
576 static inline int z_erofs_load_lz4_config(struct super_block *sb,
577 				  struct erofs_super_block *dsb,
578 				  struct z_erofs_lz4_cfgs *lz4, int len)
579 {
580 	if (lz4 || dsb->u1.lz4_max_distance) {
581 		erofs_err(sb, "lz4 algorithm isn't enabled");
582 		return -EINVAL;
583 	}
584 	return 0;
585 }
586 #endif	/* !CONFIG_EROFS_FS_ZIP */
587 
588 #ifdef CONFIG_EROFS_FS_ZIP_LZMA
589 int z_erofs_lzma_init(void);
590 void z_erofs_lzma_exit(void);
591 int z_erofs_load_lzma_config(struct super_block *sb,
592 			     struct erofs_super_block *dsb,
593 			     struct z_erofs_lzma_cfgs *lzma, int size);
594 #else
595 static inline int z_erofs_lzma_init(void) { return 0; }
596 static inline int z_erofs_lzma_exit(void) { return 0; }
597 static inline int z_erofs_load_lzma_config(struct super_block *sb,
598 			     struct erofs_super_block *dsb,
599 			     struct z_erofs_lzma_cfgs *lzma, int size) {
600 	if (lzma) {
601 		erofs_err(sb, "lzma algorithm isn't enabled");
602 		return -EINVAL;
603 	}
604 	return 0;
605 }
606 #endif	/* !CONFIG_EROFS_FS_ZIP */
607 
608 /* fscache.c */
609 #ifdef CONFIG_EROFS_FS_ONDEMAND
610 int erofs_fscache_register_fs(struct super_block *sb);
611 void erofs_fscache_unregister_fs(struct super_block *sb);
612 
613 int erofs_fscache_register_cookie(struct super_block *sb,
614 				  struct erofs_fscache **fscache,
615 				  char *name, bool need_inode);
616 void erofs_fscache_unregister_cookie(struct erofs_fscache **fscache);
617 
618 extern const struct address_space_operations erofs_fscache_access_aops;
619 #else
620 static inline int erofs_fscache_register_fs(struct super_block *sb)
621 {
622 	return 0;
623 }
624 static inline void erofs_fscache_unregister_fs(struct super_block *sb) {}
625 
626 static inline int erofs_fscache_register_cookie(struct super_block *sb,
627 						struct erofs_fscache **fscache,
628 						char *name, bool need_inode)
629 {
630 	return -EOPNOTSUPP;
631 }
632 
633 static inline void erofs_fscache_unregister_cookie(struct erofs_fscache **fscache)
634 {
635 }
636 #endif
637 
638 #define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */
639 
640 #endif	/* __EROFS_INTERNAL_H */
641