xref: /linux/fs/erofs/internal.h (revision 5c40d2e9e3ce9e81d76773c68756e9b07cce802c)
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 typedef u64 erofs_blk_t;
41 
42 struct erofs_device_info {
43 	char *path;
44 	struct erofs_fscache *fscache;
45 	struct file *file;
46 	struct dax_device *dax_dev;
47 	u64 fsoff, dax_part_off;
48 
49 	erofs_blk_t blocks;
50 	erofs_blk_t uniaddr;
51 };
52 
53 enum {
54 	EROFS_SYNC_DECOMPRESS_AUTO,
55 	EROFS_SYNC_DECOMPRESS_FORCE_ON,
56 	EROFS_SYNC_DECOMPRESS_FORCE_OFF
57 };
58 
59 struct erofs_mount_opts {
60 	/* current strategy of how to use managed cache */
61 	unsigned char cache_strategy;
62 	unsigned int mount_opt;
63 };
64 
65 struct erofs_dev_context {
66 	struct idr tree;
67 	struct rw_semaphore rwsem;
68 
69 	unsigned int extra_devices;
70 	bool flatdev;
71 };
72 
73 /* all filesystem-wide lz4 configurations */
74 struct erofs_sb_lz4_info {
75 	/* # of pages needed for EROFS lz4 rolling decompression */
76 	u16 max_distance_pages;
77 	/* maximum possible blocks for pclusters in the filesystem */
78 	u16 max_pclusterblks;
79 };
80 
81 struct erofs_domain {
82 	refcount_t ref;
83 	struct list_head list;
84 	struct fscache_volume *volume;
85 	char *domain_id;
86 };
87 
88 struct erofs_fscache {
89 	struct fscache_cookie *cookie;
90 	struct inode *inode;	/* anonymous inode for the blob */
91 
92 	/* used for share domain mode */
93 	struct erofs_domain *domain;
94 	struct list_head node;
95 	refcount_t ref;
96 	char *name;
97 };
98 
99 struct erofs_xattr_prefix_item {
100 	struct erofs_xattr_long_prefix *prefix;
101 	u8 infix_len;
102 };
103 
104 struct erofs_sb_info {
105 	struct erofs_device_info dif0;
106 	struct erofs_mount_opts opt;	/* options */
107 #ifdef CONFIG_EROFS_FS_ZIP
108 	/* list for all registered superblocks, mainly for shrinker */
109 	struct list_head list;
110 	struct mutex umount_mutex;
111 
112 	/* managed XArray arranged in physical block number */
113 	struct xarray managed_pslots;
114 
115 	unsigned int sync_decompress;	/* strategy for sync decompression */
116 	unsigned int shrinker_run_no;
117 
118 	/* pseudo inode to manage cached pages */
119 	struct inode *managed_cache;
120 
121 	struct erofs_sb_lz4_info lz4;
122 #endif	/* CONFIG_EROFS_FS_ZIP */
123 	struct inode *packed_inode;
124 	struct inode *metabox_inode;
125 	struct erofs_dev_context *devs;
126 	u64 total_blocks;
127 
128 	u32 meta_blkaddr;
129 #ifdef CONFIG_EROFS_FS_XATTR
130 	u32 xattr_blkaddr;
131 	u32 xattr_prefix_start;
132 	u8 xattr_prefix_count;
133 	u8 ishare_xattr_prefix_id;
134 	struct erofs_xattr_prefix_item *xattr_prefixes;
135 	unsigned int xattr_filter_reserved;
136 #endif
137 	u16 device_id_mask;	/* valid bits of device id to be used */
138 
139 	unsigned char islotbits;	/* inode slot unit size in bit shift */
140 	unsigned char blkszbits;	/* filesystem block size in bit shift */
141 
142 	u32 sb_size;			/* total superblock size */
143 	u32 fixed_nsec;
144 	s64 epoch;
145 
146 	/* what we really care is nid, rather than ino.. */
147 	erofs_nid_t root_nid;
148 	erofs_nid_t packed_nid;
149 	erofs_nid_t metabox_nid;
150 	/* used for statfs, f_files - f_favail */
151 	u64 inos;
152 
153 	char *volume_name;
154 	u32 feature_compat;
155 	u32 feature_incompat;
156 	u16 available_compr_algs;
157 
158 	/* sysfs support */
159 	struct kobject s_kobj;		/* /sys/fs/erofs/<devname> */
160 	struct completion s_kobj_unregister;
161 	erofs_off_t dir_ra_bytes;
162 
163 	/* fscache support */
164 	struct fscache_volume *volume;
165 	struct erofs_domain *domain;
166 	char *fsid;
167 	char *domain_id;
168 };
169 
170 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
171 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)
172 
173 /* Mount flags set via mount options or defaults */
174 #define EROFS_MOUNT_XATTR_USER		0x00000010
175 #define EROFS_MOUNT_POSIX_ACL		0x00000020
176 #define EROFS_MOUNT_DAX_ALWAYS		0x00000040
177 #define EROFS_MOUNT_DAX_NEVER		0x00000080
178 #define EROFS_MOUNT_DIRECT_IO		0x00000100
179 #define EROFS_MOUNT_INODE_SHARE		0x00000200
180 
181 #define clear_opt(opt, option)	((opt)->mount_opt &= ~EROFS_MOUNT_##option)
182 #define set_opt(opt, option)	((opt)->mount_opt |= EROFS_MOUNT_##option)
183 #define test_opt(opt, option)	((opt)->mount_opt & EROFS_MOUNT_##option)
184 
185 static inline bool erofs_is_fileio_mode(struct erofs_sb_info *sbi)
186 {
187 	return IS_ENABLED(CONFIG_EROFS_FS_BACKED_BY_FILE) && sbi->dif0.file;
188 }
189 
190 extern struct file_system_type erofs_anon_fs_type;
191 
192 static inline bool erofs_is_fscache_mode(struct super_block *sb)
193 {
194 	return IS_ENABLED(CONFIG_EROFS_FS_ONDEMAND) &&
195 			!erofs_is_fileio_mode(EROFS_SB(sb)) && !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 struct erofs_buf {
205 	struct address_space *mapping;
206 	struct file *file;
207 	u64 off;
208 	struct page *page;
209 	void *base;
210 };
211 #define __EROFS_BUF_INITIALIZER	((struct erofs_buf){ .page = NULL })
212 
213 #define erofs_blknr(sb, pos)	((erofs_blk_t)((pos) >> (sb)->s_blocksize_bits))
214 #define erofs_blkoff(sb, pos)	((pos) & ((sb)->s_blocksize - 1))
215 #define erofs_pos(sb, blk)	((erofs_off_t)(blk) << (sb)->s_blocksize_bits)
216 #define erofs_iblks(i)	(round_up((i)->i_size, i_blocksize(i)) >> (i)->i_blkbits)
217 
218 #define EROFS_FEATURE_FUNCS(name, compat, feature) \
219 static inline bool erofs_sb_has_##name(struct erofs_sb_info *sbi) \
220 { \
221 	return sbi->feature_##compat & EROFS_FEATURE_##feature; \
222 }
223 
224 EROFS_FEATURE_FUNCS(lz4_0padding, incompat, INCOMPAT_LZ4_0PADDING)
225 EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS)
226 EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER)
227 EROFS_FEATURE_FUNCS(chunked_file, incompat, INCOMPAT_CHUNKED_FILE)
228 EROFS_FEATURE_FUNCS(device_table, incompat, INCOMPAT_DEVICE_TABLE)
229 EROFS_FEATURE_FUNCS(compr_head2, incompat, INCOMPAT_COMPR_HEAD2)
230 EROFS_FEATURE_FUNCS(ztailpacking, incompat, INCOMPAT_ZTAILPACKING)
231 EROFS_FEATURE_FUNCS(fragments, incompat, INCOMPAT_FRAGMENTS)
232 EROFS_FEATURE_FUNCS(dedupe, incompat, INCOMPAT_DEDUPE)
233 EROFS_FEATURE_FUNCS(xattr_prefixes, incompat, INCOMPAT_XATTR_PREFIXES)
234 EROFS_FEATURE_FUNCS(48bit, incompat, INCOMPAT_48BIT)
235 EROFS_FEATURE_FUNCS(metabox, incompat, INCOMPAT_METABOX)
236 EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
237 EROFS_FEATURE_FUNCS(xattr_filter, compat, COMPAT_XATTR_FILTER)
238 EROFS_FEATURE_FUNCS(shared_ea_in_metabox, compat, COMPAT_SHARED_EA_IN_METABOX)
239 EROFS_FEATURE_FUNCS(plain_xattr_pfx, compat, COMPAT_PLAIN_XATTR_PFX)
240 EROFS_FEATURE_FUNCS(ishare_xattrs, compat, COMPAT_ISHARE_XATTRS)
241 
242 static inline u64 erofs_nid_to_ino64(struct erofs_sb_info *sbi, erofs_nid_t nid)
243 {
244 	if (!erofs_sb_has_metabox(sbi))
245 		return nid;
246 
247 	/*
248 	 * When metadata compression is enabled, avoid generating excessively
249 	 * large inode numbers for metadata-compressed inodes.  Shift NIDs in
250 	 * the 31-62 bit range left by one and move the metabox flag to bit 31.
251 	 *
252 	 * Note: on-disk NIDs remain unchanged as they are primarily used for
253 	 * compatibility with non-LFS 32-bit applications.
254 	 */
255 	return ((nid << 1) & GENMASK_ULL(63, 32)) | (nid & GENMASK(30, 0)) |
256 		((nid >> EROFS_DIRENT_NID_METABOX_BIT) << 31);
257 }
258 
259 /* atomic flag definitions */
260 #define EROFS_I_EA_INITED_BIT	0
261 #define EROFS_I_Z_INITED_BIT	1
262 
263 /* bitlock definitions (arranged in reverse order) */
264 #define EROFS_I_BL_XATTR_BIT	(BITS_PER_LONG - 1)
265 #define EROFS_I_BL_Z_BIT	(BITS_PER_LONG - 2)
266 
267 /* default readahead size of directories */
268 #define EROFS_DIR_RA_BYTES	16384
269 
270 struct erofs_inode_fingerprint {
271 	u8 *opaque;
272 	int size;
273 };
274 
275 struct erofs_inode {
276 	erofs_nid_t nid;
277 
278 	/* atomic flags (including bitlocks) */
279 	unsigned long flags;
280 
281 	unsigned char datalayout;
282 	unsigned char inode_isize;
283 	bool dot_omitted;
284 	unsigned int xattr_isize;
285 
286 	unsigned int xattr_name_filter;
287 	unsigned int xattr_shared_count;
288 	unsigned int *xattr_shared_xattrs;
289 
290 	union {
291 		erofs_blk_t startblk;
292 		struct {
293 			unsigned short	chunkformat;
294 			unsigned char	chunkbits;
295 		};
296 #ifdef CONFIG_EROFS_FS_ZIP
297 		struct {
298 			unsigned short z_advise;
299 			unsigned char  z_algorithmtype[2];
300 			unsigned char  z_lclusterbits;
301 			union {
302 				u64    z_tailextent_headlcn;
303 				u64    z_extents;
304 			};
305 			erofs_off_t    z_fragmentoff;
306 			unsigned short z_idata_size;
307 		};
308 #endif	/* CONFIG_EROFS_FS_ZIP */
309 	};
310 #ifdef CONFIG_EROFS_FS_PAGE_CACHE_SHARE
311 	struct list_head ishare_list;
312 	union {
313 		/* for each anon shared inode */
314 		struct {
315 			struct erofs_inode_fingerprint fingerprint;
316 			spinlock_t ishare_lock;
317 		};
318 		/* for each real inode */
319 		struct inode *sharedinode;
320 	};
321 #endif
322 	/* the corresponding vfs inode */
323 	struct inode vfs_inode;
324 };
325 
326 #define EROFS_I(ptr)	container_of(ptr, struct erofs_inode, vfs_inode)
327 
328 static inline bool erofs_inode_in_metabox(struct inode *inode)
329 {
330 	return EROFS_I(inode)->nid & BIT_ULL(EROFS_DIRENT_NID_METABOX_BIT);
331 }
332 
333 static inline erofs_off_t erofs_iloc(struct inode *inode)
334 {
335 	struct erofs_sb_info *sbi = EROFS_I_SB(inode);
336 	erofs_nid_t nid_lo = EROFS_I(inode)->nid & EROFS_DIRENT_NID_MASK;
337 
338 	if (erofs_inode_in_metabox(inode))
339 		return nid_lo << sbi->islotbits;
340 	return erofs_pos(inode->i_sb, sbi->meta_blkaddr) +
341 		(nid_lo << sbi->islotbits);
342 }
343 
344 static inline unsigned int erofs_inode_version(unsigned int ifmt)
345 {
346 	return (ifmt >> EROFS_I_VERSION_BIT) & EROFS_I_VERSION_MASK;
347 }
348 
349 static inline unsigned int erofs_inode_datalayout(unsigned int ifmt)
350 {
351 	return (ifmt >> EROFS_I_DATALAYOUT_BIT) & EROFS_I_DATALAYOUT_MASK;
352 }
353 
354 /* reclaiming is never triggered when allocating new folios. */
355 static inline struct folio *erofs_grab_folio_nowait(struct address_space *as,
356 						    pgoff_t index)
357 {
358 	return __filemap_get_folio(as, index,
359 			FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT,
360 			readahead_gfp_mask(as) & ~__GFP_RECLAIM);
361 }
362 
363 /* Allocated on disk at @m_pa (e.g. NOT a fragment extent) */
364 #define EROFS_MAP_MAPPED		0x0001
365 /* Located in metadata (could be copied from bd_inode) */
366 #define EROFS_MAP_META			0x0002
367 /* @m_llen may be truncated by the runtime compared to the on-disk record */
368 #define EROFS_MAP_PARTIAL_MAPPED	0x0004
369 /* The on-disk @m_llen may cover only part of the encoded data */
370 #define EROFS_MAP_PARTIAL_REF		0x0008
371 /* Located in the special packed inode */
372 #define EROFS_MAP_FRAGMENT		0x0010
373 /* The encoded on-disk data will be fully handled (decompressed) */
374 #define EROFS_MAP_FULL(f)	(!((f) & (EROFS_MAP_PARTIAL_MAPPED | \
375 					  EROFS_MAP_PARTIAL_REF)))
376 
377 struct erofs_map_blocks {
378 	struct erofs_buf buf;
379 
380 	erofs_off_t m_pa, m_la;
381 	u64 m_plen, m_llen;
382 
383 	unsigned short m_deviceid;
384 	char m_algorithmformat;
385 	unsigned int m_flags;
386 };
387 
388 /*
389  * Used to get the exact decompressed length, e.g. fiemap (consider lookback
390  * approach instead if possible since it's more metadata lightweight.)
391  */
392 #define EROFS_GET_BLOCKS_FIEMAP		0x0001
393 /* Used to map the whole extent if non-negligible data is requested for LZMA */
394 #define EROFS_GET_BLOCKS_READMORE	0x0002
395 /* Used to map tail extent for tailpacking inline or fragment pcluster */
396 #define EROFS_GET_BLOCKS_FINDTAIL	0x0004
397 
398 enum {
399 	Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX,
400 	Z_EROFS_COMPRESSION_INTERLACED,
401 	Z_EROFS_COMPRESSION_RUNTIME_MAX
402 };
403 
404 struct erofs_map_dev {
405 	struct super_block *m_sb;
406 	struct erofs_device_info *m_dif;
407 	struct block_device *m_bdev;
408 
409 	erofs_off_t m_pa;
410 	unsigned int m_deviceid;
411 };
412 
413 extern const struct super_operations erofs_sops;
414 
415 extern const struct address_space_operations erofs_aops;
416 extern const struct address_space_operations erofs_fileio_aops;
417 extern const struct address_space_operations z_erofs_aops;
418 extern const struct address_space_operations erofs_fscache_access_aops;
419 
420 extern const struct inode_operations erofs_generic_iops;
421 extern const struct inode_operations erofs_symlink_iops;
422 extern const struct inode_operations erofs_fast_symlink_iops;
423 extern const struct inode_operations erofs_dir_iops;
424 
425 extern const struct file_operations erofs_file_fops;
426 extern const struct file_operations erofs_dir_fops;
427 extern const struct file_operations erofs_ishare_fops;
428 
429 extern const struct iomap_ops z_erofs_iomap_report_ops;
430 
431 /* flags for erofs_fscache_register_cookie() */
432 #define EROFS_REG_COOKIE_SHARE		0x0001
433 #define EROFS_REG_COOKIE_NEED_NOEXIST	0x0002
434 
435 void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf,
436 			  erofs_off_t *offset, int *lengthp);
437 void erofs_unmap_metabuf(struct erofs_buf *buf);
438 void erofs_put_metabuf(struct erofs_buf *buf);
439 void *erofs_bread(struct erofs_buf *buf, erofs_off_t offset, bool need_kmap);
440 int erofs_init_metabuf(struct erofs_buf *buf, struct super_block *sb,
441 		       bool in_metabox);
442 void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,
443 			 erofs_off_t offset, bool in_metabox);
444 int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *dev);
445 int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
446 		 u64 start, u64 len);
447 int erofs_map_blocks(struct inode *inode, struct erofs_map_blocks *map);
448 void erofs_onlinefolio_init(struct folio *folio);
449 void erofs_onlinefolio_split(struct folio *folio);
450 void erofs_onlinefolio_end(struct folio *folio, int err, bool dirty);
451 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid);
452 int erofs_getattr(struct mnt_idmap *idmap, const struct path *path,
453 		  struct kstat *stat, u32 request_mask,
454 		  unsigned int query_flags);
455 int erofs_namei(struct inode *dir, const struct qstr *name,
456 		erofs_nid_t *nid, unsigned int *d_type);
457 
458 static inline void *erofs_vm_map_ram(struct page **pages, unsigned int count)
459 {
460 	int retried = 0;
461 
462 	while (1) {
463 		void *p = vm_map_ram(pages, count, -1);
464 
465 		/* retry two more times (totally 3 times) */
466 		if (p || ++retried >= 3)
467 			return p;
468 		vm_unmap_aliases();
469 	}
470 	return NULL;
471 }
472 
473 static inline const struct address_space_operations *
474 erofs_get_aops(struct inode *realinode, bool no_fscache)
475 {
476 	if (erofs_inode_is_data_compressed(EROFS_I(realinode)->datalayout)) {
477 		if (!IS_ENABLED(CONFIG_EROFS_FS_ZIP))
478 			return ERR_PTR(-EOPNOTSUPP);
479 		DO_ONCE_LITE_IF(realinode->i_blkbits != PAGE_SHIFT,
480 			  erofs_info, realinode->i_sb,
481 			  "EXPERIMENTAL EROFS subpage compressed block support in use. Use at your own risk!");
482 		return &z_erofs_aops;
483 	}
484 	if (IS_ENABLED(CONFIG_EROFS_FS_ONDEMAND) && !no_fscache &&
485 	    erofs_is_fscache_mode(realinode->i_sb))
486 		return &erofs_fscache_access_aops;
487 	if (IS_ENABLED(CONFIG_EROFS_FS_BACKED_BY_FILE) &&
488 	    erofs_is_fileio_mode(EROFS_SB(realinode->i_sb)))
489 		return &erofs_fileio_aops;
490 	return &erofs_aops;
491 }
492 
493 int erofs_register_sysfs(struct super_block *sb);
494 void erofs_unregister_sysfs(struct super_block *sb);
495 int __init erofs_init_sysfs(void);
496 void erofs_exit_sysfs(void);
497 
498 struct page *__erofs_allocpage(struct page **pagepool, gfp_t gfp, bool tryrsv);
499 static inline struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp)
500 {
501 	return __erofs_allocpage(pagepool, gfp, false);
502 }
503 static inline void erofs_pagepool_add(struct page **pagepool, struct page *page)
504 {
505 	set_page_private(page, (unsigned long)*pagepool);
506 	*pagepool = page;
507 }
508 void erofs_release_pages(struct page **pagepool);
509 
510 #ifdef CONFIG_EROFS_FS_ZIP
511 #define MNGD_MAPPING(sbi)	((sbi)->managed_cache->i_mapping)
512 
513 extern atomic_long_t erofs_global_shrink_cnt;
514 void erofs_shrinker_register(struct super_block *sb);
515 void erofs_shrinker_unregister(struct super_block *sb);
516 int __init erofs_init_shrinker(void);
517 void erofs_exit_shrinker(void);
518 int __init z_erofs_init_subsystem(void);
519 void z_erofs_exit_subsystem(void);
520 int z_erofs_init_super(struct super_block *sb);
521 unsigned long z_erofs_shrink_scan(struct erofs_sb_info *sbi,
522 				  unsigned long nr_shrink);
523 int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map,
524 			    int flags);
525 void *z_erofs_get_gbuf(unsigned int requiredpages);
526 void z_erofs_put_gbuf(void *ptr);
527 int z_erofs_gbuf_growsize(unsigned int nrpages);
528 int __init z_erofs_gbuf_init(void);
529 void z_erofs_gbuf_exit(void);
530 #else
531 static inline void erofs_shrinker_register(struct super_block *sb) {}
532 static inline void erofs_shrinker_unregister(struct super_block *sb) {}
533 static inline int erofs_init_shrinker(void) { return 0; }
534 static inline void erofs_exit_shrinker(void) {}
535 static inline int z_erofs_init_subsystem(void) { return 0; }
536 static inline void z_erofs_exit_subsystem(void) {}
537 static inline int z_erofs_init_super(struct super_block *sb) { return 0; }
538 #endif	/* !CONFIG_EROFS_FS_ZIP */
539 int z_erofs_parse_cfgs(struct super_block *sb, struct erofs_super_block *dsb);
540 
541 #ifdef CONFIG_EROFS_FS_BACKED_BY_FILE
542 struct bio *erofs_fileio_bio_alloc(struct erofs_map_dev *mdev);
543 void erofs_fileio_submit_bio(struct bio *bio);
544 #else
545 static inline struct bio *erofs_fileio_bio_alloc(struct erofs_map_dev *mdev) { return NULL; }
546 static inline void erofs_fileio_submit_bio(struct bio *bio) {}
547 #endif
548 
549 #ifdef CONFIG_EROFS_FS_ONDEMAND
550 int erofs_fscache_register_fs(struct super_block *sb);
551 void erofs_fscache_unregister_fs(struct super_block *sb);
552 
553 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
554 					char *name, unsigned int flags);
555 void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache);
556 struct bio *erofs_fscache_bio_alloc(struct erofs_map_dev *mdev);
557 void erofs_fscache_submit_bio(struct bio *bio);
558 #else
559 static inline int erofs_fscache_register_fs(struct super_block *sb)
560 {
561 	return -EOPNOTSUPP;
562 }
563 static inline void erofs_fscache_unregister_fs(struct super_block *sb) {}
564 
565 static inline
566 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
567 					char *name, unsigned int flags)
568 {
569 	return ERR_PTR(-EOPNOTSUPP);
570 }
571 
572 static inline void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache)
573 {
574 }
575 static inline struct bio *erofs_fscache_bio_alloc(struct erofs_map_dev *mdev) { return NULL; }
576 static inline void erofs_fscache_submit_bio(struct bio *bio) {}
577 #endif
578 
579 #ifdef CONFIG_EROFS_FS_PAGE_CACHE_SHARE
580 int __init erofs_init_ishare(void);
581 void erofs_exit_ishare(void);
582 bool erofs_ishare_fill_inode(struct inode *inode);
583 void erofs_ishare_free_inode(struct inode *inode);
584 struct inode *erofs_real_inode(struct inode *inode, bool *need_iput);
585 #else
586 static inline int erofs_init_ishare(void) { return 0; }
587 static inline void erofs_exit_ishare(void) {}
588 static inline bool erofs_ishare_fill_inode(struct inode *inode) { return false; }
589 static inline void erofs_ishare_free_inode(struct inode *inode) {}
590 static inline struct inode *erofs_real_inode(struct inode *inode, bool *need_iput)
591 {
592 	*need_iput = false;
593 	return inode;
594 }
595 #endif
596 
597 long erofs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
598 long erofs_compat_ioctl(struct file *filp, unsigned int cmd,
599 			unsigned long arg);
600 
601 #endif	/* __EROFS_INTERNAL_H */
602