xref: /openbmc/linux/fs/erofs/internal.h (revision 1edd0337)
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/magic.h>
16 #include <linux/slab.h>
17 #include <linux/vmalloc.h>
18 #include <linux/iomap.h>
19 #include "erofs_fs.h"
20 
21 /* redefine pr_fmt "erofs: " */
22 #undef pr_fmt
23 #define pr_fmt(fmt) "erofs: " fmt
24 
25 __printf(3, 4) void _erofs_err(struct super_block *sb,
26 			       const char *function, const char *fmt, ...);
27 #define erofs_err(sb, fmt, ...)	\
28 	_erofs_err(sb, __func__, fmt "\n", ##__VA_ARGS__)
29 __printf(3, 4) void _erofs_info(struct super_block *sb,
30 			       const char *function, const char *fmt, ...);
31 #define erofs_info(sb, fmt, ...) \
32 	_erofs_info(sb, __func__, fmt "\n", ##__VA_ARGS__)
33 #ifdef CONFIG_EROFS_FS_DEBUG
34 #define erofs_dbg(x, ...)       pr_debug(x "\n", ##__VA_ARGS__)
35 #define DBG_BUGON               BUG_ON
36 #else
37 #define erofs_dbg(x, ...)       ((void)0)
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 block_device *bdev;
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 #ifdef CONFIG_EROFS_FS_ZIP
68 	/* current strategy of how to use managed cache */
69 	unsigned char cache_strategy;
70 	/* strategy of sync decompression (0 - auto, 1 - force on, 2 - force off) */
71 	unsigned int sync_decompress;
72 
73 	/* threshold for decompression synchronously */
74 	unsigned int max_sync_decompress_pages;
75 #endif
76 	unsigned int mount_opt;
77 };
78 
79 struct erofs_dev_context {
80 	struct idr tree;
81 	struct rw_semaphore rwsem;
82 
83 	unsigned int extra_devices;
84 };
85 
86 struct erofs_fs_context {
87 	struct erofs_mount_opts opt;
88 	struct erofs_dev_context *devs;
89 	char *fsid;
90 	char *domain_id;
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_domain {
102 	refcount_t ref;
103 	struct list_head list;
104 	struct fscache_volume *volume;
105 	char *domain_id;
106 };
107 
108 struct erofs_fscache {
109 	struct fscache_cookie *cookie;
110 	struct inode *inode;	/* anonymous inode for the blob */
111 
112 	/* used for share domain mode */
113 	struct erofs_domain *domain;
114 	struct list_head node;
115 	refcount_t ref;
116 	char *name;
117 };
118 
119 struct erofs_sb_info {
120 	struct erofs_mount_opts opt;	/* options */
121 #ifdef CONFIG_EROFS_FS_ZIP
122 	/* list for all registered superblocks, mainly for shrinker */
123 	struct list_head list;
124 	struct mutex umount_mutex;
125 
126 	/* managed XArray arranged in physical block number */
127 	struct xarray managed_pslots;
128 
129 	unsigned int shrinker_run_no;
130 	u16 available_compr_algs;
131 
132 	/* pseudo inode to manage cached pages */
133 	struct inode *managed_cache;
134 
135 	struct erofs_sb_lz4_info lz4;
136 	struct inode *packed_inode;
137 #endif	/* CONFIG_EROFS_FS_ZIP */
138 	struct erofs_dev_context *devs;
139 	struct dax_device *dax_dev;
140 	u64 dax_part_off;
141 	u64 total_blocks;
142 	u32 primarydevice_blocks;
143 
144 	u32 meta_blkaddr;
145 #ifdef CONFIG_EROFS_FS_XATTR
146 	u32 xattr_blkaddr;
147 #endif
148 	u16 device_id_mask;	/* valid bits of device id to be used */
149 
150 	/* inode slot unit size in bit shift */
151 	unsigned char islotbits;
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 	/* used for statfs, f_files - f_favail */
160 	u64 inos;
161 
162 	u8 uuid[16];                    /* 128-bit uuid for volume */
163 	u8 volume_name[16];             /* volume name */
164 	u32 feature_compat;
165 	u32 feature_incompat;
166 
167 	/* sysfs support */
168 	struct kobject s_kobj;		/* /sys/fs/erofs/<devname> */
169 	struct completion s_kobj_unregister;
170 
171 	/* fscache support */
172 	struct fscache_volume *volume;
173 	struct erofs_fscache *s_fscache;
174 	struct erofs_domain *domain;
175 	char *fsid;
176 	char *domain_id;
177 };
178 
179 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
180 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)
181 
182 /* Mount flags set via mount options or defaults */
183 #define EROFS_MOUNT_XATTR_USER		0x00000010
184 #define EROFS_MOUNT_POSIX_ACL		0x00000020
185 #define EROFS_MOUNT_DAX_ALWAYS		0x00000040
186 #define EROFS_MOUNT_DAX_NEVER		0x00000080
187 
188 #define clear_opt(opt, option)	((opt)->mount_opt &= ~EROFS_MOUNT_##option)
189 #define set_opt(opt, option)	((opt)->mount_opt |= EROFS_MOUNT_##option)
190 #define test_opt(opt, option)	((opt)->mount_opt & EROFS_MOUNT_##option)
191 
192 static inline bool erofs_is_fscache_mode(struct super_block *sb)
193 {
194 	return IS_ENABLED(CONFIG_EROFS_FS_ONDEMAND) && !sb->s_bdev;
195 }
196 
197 enum {
198 	EROFS_ZIP_CACHE_DISABLED,
199 	EROFS_ZIP_CACHE_READAHEAD,
200 	EROFS_ZIP_CACHE_READAROUND
201 };
202 
203 #define EROFS_LOCKED_MAGIC     (INT_MIN | 0xE0F510CCL)
204 
205 /* basic unit of the workstation of a super_block */
206 struct erofs_workgroup {
207 	/* the workgroup index in the workstation */
208 	pgoff_t index;
209 
210 	/* overall workgroup reference count */
211 	atomic_t refcount;
212 };
213 
214 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
215 						 int val)
216 {
217 	preempt_disable();
218 	if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) {
219 		preempt_enable();
220 		return false;
221 	}
222 	return true;
223 }
224 
225 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
226 					    int orig_val)
227 {
228 	/*
229 	 * other observers should notice all modifications
230 	 * in the freezing period.
231 	 */
232 	smp_mb();
233 	atomic_set(&grp->refcount, orig_val);
234 	preempt_enable();
235 }
236 
237 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
238 {
239 	return atomic_cond_read_relaxed(&grp->refcount,
240 					VAL != EROFS_LOCKED_MAGIC);
241 }
242 
243 /* we strictly follow PAGE_SIZE and no buffer head yet */
244 #define LOG_BLOCK_SIZE		PAGE_SHIFT
245 
246 #undef LOG_SECTORS_PER_BLOCK
247 #define LOG_SECTORS_PER_BLOCK	(PAGE_SHIFT - 9)
248 
249 #undef SECTORS_PER_BLOCK
250 #define SECTORS_PER_BLOCK	(1 << SECTORS_PER_BLOCK)
251 
252 #define EROFS_BLKSIZ		(1 << LOG_BLOCK_SIZE)
253 
254 #if (EROFS_BLKSIZ % 4096 || !EROFS_BLKSIZ)
255 #error erofs cannot be used in this platform
256 #endif
257 
258 enum erofs_kmap_type {
259 	EROFS_NO_KMAP,		/* don't map the buffer */
260 	EROFS_KMAP,		/* use kmap_local_page() to map the buffer */
261 };
262 
263 struct erofs_buf {
264 	struct page *page;
265 	void *base;
266 	enum erofs_kmap_type kmap_type;
267 };
268 #define __EROFS_BUF_INITIALIZER	((struct erofs_buf){ .page = NULL })
269 
270 #define ROOT_NID(sb)		((sb)->root_nid)
271 
272 #define erofs_blknr(addr)       ((addr) / EROFS_BLKSIZ)
273 #define erofs_blkoff(addr)      ((addr) % EROFS_BLKSIZ)
274 #define blknr_to_addr(nr)       ((erofs_off_t)(nr) * EROFS_BLKSIZ)
275 
276 #define EROFS_FEATURE_FUNCS(name, compat, feature) \
277 static inline bool erofs_sb_has_##name(struct erofs_sb_info *sbi) \
278 { \
279 	return sbi->feature_##compat & EROFS_FEATURE_##feature; \
280 }
281 
282 EROFS_FEATURE_FUNCS(zero_padding, incompat, INCOMPAT_ZERO_PADDING)
283 EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS)
284 EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER)
285 EROFS_FEATURE_FUNCS(chunked_file, incompat, INCOMPAT_CHUNKED_FILE)
286 EROFS_FEATURE_FUNCS(device_table, incompat, INCOMPAT_DEVICE_TABLE)
287 EROFS_FEATURE_FUNCS(compr_head2, incompat, INCOMPAT_COMPR_HEAD2)
288 EROFS_FEATURE_FUNCS(ztailpacking, incompat, INCOMPAT_ZTAILPACKING)
289 EROFS_FEATURE_FUNCS(fragments, incompat, INCOMPAT_FRAGMENTS)
290 EROFS_FEATURE_FUNCS(dedupe, incompat, INCOMPAT_DEDUPE)
291 EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
292 
293 /* atomic flag definitions */
294 #define EROFS_I_EA_INITED_BIT	0
295 #define EROFS_I_Z_INITED_BIT	1
296 
297 /* bitlock definitions (arranged in reverse order) */
298 #define EROFS_I_BL_XATTR_BIT	(BITS_PER_LONG - 1)
299 #define EROFS_I_BL_Z_BIT	(BITS_PER_LONG - 2)
300 
301 struct erofs_inode {
302 	erofs_nid_t nid;
303 
304 	/* atomic flags (including bitlocks) */
305 	unsigned long flags;
306 
307 	unsigned char datalayout;
308 	unsigned char inode_isize;
309 	unsigned short xattr_isize;
310 
311 	unsigned int xattr_shared_count;
312 	unsigned int *xattr_shared_xattrs;
313 
314 	union {
315 		erofs_blk_t raw_blkaddr;
316 		struct {
317 			unsigned short	chunkformat;
318 			unsigned char	chunkbits;
319 		};
320 #ifdef CONFIG_EROFS_FS_ZIP
321 		struct {
322 			unsigned short z_advise;
323 			unsigned char  z_algorithmtype[2];
324 			unsigned char  z_logical_clusterbits;
325 			unsigned long  z_tailextent_headlcn;
326 			union {
327 				struct {
328 					erofs_off_t    z_idataoff;
329 					unsigned short z_idata_size;
330 				};
331 				erofs_off_t z_fragmentoff;
332 			};
333 		};
334 #endif	/* CONFIG_EROFS_FS_ZIP */
335 	};
336 	/* the corresponding vfs inode */
337 	struct inode vfs_inode;
338 };
339 
340 #define EROFS_I(ptr)	container_of(ptr, struct erofs_inode, vfs_inode)
341 
342 static inline erofs_off_t erofs_iloc(struct inode *inode)
343 {
344 	struct erofs_sb_info *sbi = EROFS_I_SB(inode);
345 
346 	return blknr_to_addr(sbi->meta_blkaddr) +
347 		(EROFS_I(inode)->nid << sbi->islotbits);
348 }
349 
350 static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit,
351 					  unsigned int bits)
352 {
353 
354 	return (value >> bit) & ((1 << bits) - 1);
355 }
356 
357 
358 static inline unsigned int erofs_inode_version(unsigned int value)
359 {
360 	return erofs_bitrange(value, EROFS_I_VERSION_BIT,
361 			      EROFS_I_VERSION_BITS);
362 }
363 
364 static inline unsigned int erofs_inode_datalayout(unsigned int value)
365 {
366 	return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT,
367 			      EROFS_I_DATALAYOUT_BITS);
368 }
369 
370 /*
371  * Different from grab_cache_page_nowait(), reclaiming is never triggered
372  * when allocating new pages.
373  */
374 static inline
375 struct page *erofs_grab_cache_page_nowait(struct address_space *mapping,
376 					  pgoff_t index)
377 {
378 	return pagecache_get_page(mapping, index,
379 			FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT,
380 			readahead_gfp_mask(mapping) & ~__GFP_RECLAIM);
381 }
382 
383 /* Has a disk mapping */
384 #define EROFS_MAP_MAPPED	0x0001
385 /* Located in metadata (could be copied from bd_inode) */
386 #define EROFS_MAP_META		0x0002
387 /* The extent is encoded */
388 #define EROFS_MAP_ENCODED	0x0004
389 /* The length of extent is full */
390 #define EROFS_MAP_FULL_MAPPED	0x0008
391 /* Located in the special packed inode */
392 #define EROFS_MAP_FRAGMENT	0x0010
393 /* The extent refers to partial decompressed data */
394 #define EROFS_MAP_PARTIAL_REF	0x0020
395 
396 struct erofs_map_blocks {
397 	struct erofs_buf buf;
398 
399 	erofs_off_t m_pa, m_la;
400 	u64 m_plen, m_llen;
401 
402 	unsigned short m_deviceid;
403 	char m_algorithmformat;
404 	unsigned int m_flags;
405 };
406 
407 /*
408  * Used to get the exact decompressed length, e.g. fiemap (consider lookback
409  * approach instead if possible since it's more metadata lightweight.)
410  */
411 #define EROFS_GET_BLOCKS_FIEMAP		0x0001
412 /* Used to map the whole extent if non-negligible data is requested for LZMA */
413 #define EROFS_GET_BLOCKS_READMORE	0x0002
414 /* Used to map tail extent for tailpacking inline or fragment pcluster */
415 #define EROFS_GET_BLOCKS_FINDTAIL	0x0004
416 
417 enum {
418 	Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX,
419 	Z_EROFS_COMPRESSION_INTERLACED,
420 	Z_EROFS_COMPRESSION_RUNTIME_MAX
421 };
422 
423 struct erofs_map_dev {
424 	struct erofs_fscache *m_fscache;
425 	struct block_device *m_bdev;
426 	struct dax_device *m_daxdev;
427 	u64 m_dax_part_off;
428 
429 	erofs_off_t m_pa;
430 	unsigned int m_deviceid;
431 };
432 
433 extern struct file_system_type erofs_fs_type;
434 extern const struct super_operations erofs_sops;
435 
436 extern const struct address_space_operations erofs_raw_access_aops;
437 extern const struct address_space_operations z_erofs_aops;
438 extern const struct address_space_operations erofs_fscache_access_aops;
439 
440 extern const struct inode_operations erofs_generic_iops;
441 extern const struct inode_operations erofs_symlink_iops;
442 extern const struct inode_operations erofs_fast_symlink_iops;
443 extern const struct inode_operations erofs_dir_iops;
444 
445 extern const struct file_operations erofs_file_fops;
446 extern const struct file_operations erofs_dir_fops;
447 
448 extern const struct iomap_ops z_erofs_iomap_report_ops;
449 
450 /* flags for erofs_fscache_register_cookie() */
451 #define EROFS_REG_COOKIE_SHARE		0x0001
452 #define EROFS_REG_COOKIE_NEED_NOEXIST	0x0002
453 
454 void erofs_unmap_metabuf(struct erofs_buf *buf);
455 void erofs_put_metabuf(struct erofs_buf *buf);
456 void *erofs_bread(struct erofs_buf *buf, struct inode *inode,
457 		  erofs_blk_t blkaddr, enum erofs_kmap_type type);
458 void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,
459 			 erofs_blk_t blkaddr, enum erofs_kmap_type type);
460 int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *dev);
461 int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
462 		 u64 start, u64 len);
463 int erofs_map_blocks(struct inode *inode, struct erofs_map_blocks *map);
464 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid);
465 int erofs_getattr(struct mnt_idmap *idmap, const struct path *path,
466 		  struct kstat *stat, u32 request_mask,
467 		  unsigned int query_flags);
468 int erofs_namei(struct inode *dir, const struct qstr *name,
469 		erofs_nid_t *nid, unsigned int *d_type);
470 
471 static inline void *erofs_vm_map_ram(struct page **pages, unsigned int count)
472 {
473 	int retried = 0;
474 
475 	while (1) {
476 		void *p = vm_map_ram(pages, count, -1);
477 
478 		/* retry two more times (totally 3 times) */
479 		if (p || ++retried >= 3)
480 			return p;
481 		vm_unmap_aliases();
482 	}
483 	return NULL;
484 }
485 
486 void *erofs_get_pcpubuf(unsigned int requiredpages);
487 void erofs_put_pcpubuf(void *ptr);
488 int erofs_pcpubuf_growsize(unsigned int nrpages);
489 void __init erofs_pcpubuf_init(void);
490 void erofs_pcpubuf_exit(void);
491 
492 int erofs_register_sysfs(struct super_block *sb);
493 void erofs_unregister_sysfs(struct super_block *sb);
494 int __init erofs_init_sysfs(void);
495 void erofs_exit_sysfs(void);
496 
497 struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp);
498 static inline void erofs_pagepool_add(struct page **pagepool, struct page *page)
499 {
500 	set_page_private(page, (unsigned long)*pagepool);
501 	*pagepool = page;
502 }
503 void erofs_release_pages(struct page **pagepool);
504 
505 #ifdef CONFIG_EROFS_FS_ZIP
506 int erofs_workgroup_put(struct erofs_workgroup *grp);
507 struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb,
508 					     pgoff_t index);
509 struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb,
510 					       struct erofs_workgroup *grp);
511 void erofs_workgroup_free_rcu(struct erofs_workgroup *grp);
512 void erofs_shrinker_register(struct super_block *sb);
513 void erofs_shrinker_unregister(struct super_block *sb);
514 int __init erofs_init_shrinker(void);
515 void erofs_exit_shrinker(void);
516 int __init z_erofs_init_zip_subsystem(void);
517 void z_erofs_exit_zip_subsystem(void);
518 int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
519 				       struct erofs_workgroup *egrp);
520 int erofs_try_to_free_cached_page(struct page *page);
521 int z_erofs_load_lz4_config(struct super_block *sb,
522 			    struct erofs_super_block *dsb,
523 			    struct z_erofs_lz4_cfgs *lz4, int len);
524 int z_erofs_fill_inode(struct inode *inode);
525 int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map,
526 			    int flags);
527 #else
528 static inline void erofs_shrinker_register(struct super_block *sb) {}
529 static inline void erofs_shrinker_unregister(struct super_block *sb) {}
530 static inline int erofs_init_shrinker(void) { return 0; }
531 static inline void erofs_exit_shrinker(void) {}
532 static inline int z_erofs_init_zip_subsystem(void) { return 0; }
533 static inline void z_erofs_exit_zip_subsystem(void) {}
534 static inline int z_erofs_load_lz4_config(struct super_block *sb,
535 				  struct erofs_super_block *dsb,
536 				  struct z_erofs_lz4_cfgs *lz4, int len)
537 {
538 	if (lz4 || dsb->u1.lz4_max_distance) {
539 		erofs_err(sb, "lz4 algorithm isn't enabled");
540 		return -EINVAL;
541 	}
542 	return 0;
543 }
544 static inline int z_erofs_fill_inode(struct inode *inode) { return -EOPNOTSUPP; }
545 #endif	/* !CONFIG_EROFS_FS_ZIP */
546 
547 #ifdef CONFIG_EROFS_FS_ZIP_LZMA
548 int __init z_erofs_lzma_init(void);
549 void z_erofs_lzma_exit(void);
550 int z_erofs_load_lzma_config(struct super_block *sb,
551 			     struct erofs_super_block *dsb,
552 			     struct z_erofs_lzma_cfgs *lzma, int size);
553 #else
554 static inline int z_erofs_lzma_init(void) { return 0; }
555 static inline int z_erofs_lzma_exit(void) { return 0; }
556 static inline int z_erofs_load_lzma_config(struct super_block *sb,
557 			     struct erofs_super_block *dsb,
558 			     struct z_erofs_lzma_cfgs *lzma, int size) {
559 	if (lzma) {
560 		erofs_err(sb, "lzma algorithm isn't enabled");
561 		return -EINVAL;
562 	}
563 	return 0;
564 }
565 #endif	/* !CONFIG_EROFS_FS_ZIP_LZMA */
566 
567 #ifdef CONFIG_EROFS_FS_ONDEMAND
568 int erofs_fscache_register_fs(struct super_block *sb);
569 void erofs_fscache_unregister_fs(struct super_block *sb);
570 
571 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
572 					char *name, unsigned int flags);
573 void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache);
574 #else
575 static inline int erofs_fscache_register_fs(struct super_block *sb)
576 {
577 	return -EOPNOTSUPP;
578 }
579 static inline void erofs_fscache_unregister_fs(struct super_block *sb) {}
580 
581 static inline
582 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
583 					char *name, unsigned int flags)
584 {
585 	return ERR_PTR(-EOPNOTSUPP);
586 }
587 
588 static inline void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache)
589 {
590 }
591 #endif
592 
593 #define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */
594 
595 #endif	/* __EROFS_INTERNAL_H */
596