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 };
79 
80 struct erofs_dev_context {
81 	struct idr tree;
82 	struct rw_semaphore rwsem;
83 
84 	unsigned int extra_devices;
85 };
86 
87 struct erofs_fs_context {
88 	struct erofs_mount_opts opt;
89 	struct erofs_dev_context *devs;
90 	char *fsid;
91 	char *domain_id;
92 };
93 
94 /* all filesystem-wide lz4 configurations */
95 struct erofs_sb_lz4_info {
96 	/* # of pages needed for EROFS lz4 rolling decompression */
97 	u16 max_distance_pages;
98 	/* maximum possible blocks for pclusters in the filesystem */
99 	u16 max_pclusterblks;
100 };
101 
102 struct erofs_domain {
103 	refcount_t ref;
104 	struct list_head list;
105 	struct fscache_volume *volume;
106 	char *domain_id;
107 };
108 
109 struct erofs_fscache {
110 	struct fscache_cookie *cookie;
111 	struct inode *inode;
112 	struct inode *anon_inode;
113 	struct erofs_domain *domain;
114 	char *name;
115 };
116 
117 struct erofs_sb_info {
118 	struct erofs_mount_opts opt;	/* options */
119 #ifdef CONFIG_EROFS_FS_ZIP
120 	/* list for all registered superblocks, mainly for shrinker */
121 	struct list_head list;
122 	struct mutex umount_mutex;
123 
124 	/* managed XArray arranged in physical block number */
125 	struct xarray managed_pslots;
126 
127 	unsigned int shrinker_run_no;
128 	u16 available_compr_algs;
129 
130 	/* pseudo inode to manage cached pages */
131 	struct inode *managed_cache;
132 
133 	struct erofs_sb_lz4_info lz4;
134 	struct inode *packed_inode;
135 #endif	/* CONFIG_EROFS_FS_ZIP */
136 	struct erofs_dev_context *devs;
137 	struct dax_device *dax_dev;
138 	u64 dax_part_off;
139 	u64 total_blocks;
140 	u32 primarydevice_blocks;
141 
142 	u32 meta_blkaddr;
143 #ifdef CONFIG_EROFS_FS_XATTR
144 	u32 xattr_blkaddr;
145 #endif
146 	u16 device_id_mask;	/* valid bits of device id to be used */
147 
148 	/* inode slot unit size in bit shift */
149 	unsigned char islotbits;
150 
151 	u32 sb_size;			/* total superblock size */
152 	u32 build_time_nsec;
153 	u64 build_time;
154 
155 	/* what we really care is nid, rather than ino.. */
156 	erofs_nid_t root_nid;
157 	/* used for statfs, f_files - f_favail */
158 	u64 inos;
159 
160 	u8 uuid[16];                    /* 128-bit uuid for volume */
161 	u8 volume_name[16];             /* volume name */
162 	u32 feature_compat;
163 	u32 feature_incompat;
164 
165 	/* sysfs support */
166 	struct kobject s_kobj;		/* /sys/fs/erofs/<devname> */
167 	struct completion s_kobj_unregister;
168 
169 	/* fscache support */
170 	struct fscache_volume *volume;
171 	struct erofs_fscache *s_fscache;
172 	struct erofs_domain *domain;
173 	char *fsid;
174 	char *domain_id;
175 };
176 
177 #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
178 #define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)
179 
180 /* Mount flags set via mount options or defaults */
181 #define EROFS_MOUNT_XATTR_USER		0x00000010
182 #define EROFS_MOUNT_POSIX_ACL		0x00000020
183 #define EROFS_MOUNT_DAX_ALWAYS		0x00000040
184 #define EROFS_MOUNT_DAX_NEVER		0x00000080
185 
186 #define clear_opt(opt, option)	((opt)->mount_opt &= ~EROFS_MOUNT_##option)
187 #define set_opt(opt, option)	((opt)->mount_opt |= EROFS_MOUNT_##option)
188 #define test_opt(opt, option)	((opt)->mount_opt & EROFS_MOUNT_##option)
189 
erofs_is_fscache_mode(struct super_block * sb)190 static inline bool erofs_is_fscache_mode(struct super_block *sb)
191 {
192 	return IS_ENABLED(CONFIG_EROFS_FS_ONDEMAND) && !sb->s_bdev;
193 }
194 
195 enum {
196 	EROFS_ZIP_CACHE_DISABLED,
197 	EROFS_ZIP_CACHE_READAHEAD,
198 	EROFS_ZIP_CACHE_READAROUND
199 };
200 
201 #define EROFS_LOCKED_MAGIC     (INT_MIN | 0xE0F510CCL)
202 
203 /* basic unit of the workstation of a super_block */
204 struct erofs_workgroup {
205 	/* the workgroup index in the workstation */
206 	pgoff_t index;
207 
208 	/* overall workgroup reference count */
209 	atomic_t refcount;
210 };
211 
erofs_workgroup_try_to_freeze(struct erofs_workgroup * grp,int val)212 static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
213 						 int val)
214 {
215 	preempt_disable();
216 	if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) {
217 		preempt_enable();
218 		return false;
219 	}
220 	return true;
221 }
222 
erofs_workgroup_unfreeze(struct erofs_workgroup * grp,int orig_val)223 static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
224 					    int orig_val)
225 {
226 	/*
227 	 * other observers should notice all modifications
228 	 * in the freezing period.
229 	 */
230 	smp_mb();
231 	atomic_set(&grp->refcount, orig_val);
232 	preempt_enable();
233 }
234 
erofs_wait_on_workgroup_freezed(struct erofs_workgroup * grp)235 static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
236 {
237 	return atomic_cond_read_relaxed(&grp->refcount,
238 					VAL != EROFS_LOCKED_MAGIC);
239 }
240 
241 /* we strictly follow PAGE_SIZE and no buffer head yet */
242 #define LOG_BLOCK_SIZE		PAGE_SHIFT
243 
244 #undef LOG_SECTORS_PER_BLOCK
245 #define LOG_SECTORS_PER_BLOCK	(PAGE_SHIFT - 9)
246 
247 #undef SECTORS_PER_BLOCK
248 #define SECTORS_PER_BLOCK	(1 << SECTORS_PER_BLOCK)
249 
250 #define EROFS_BLKSIZ		(1 << LOG_BLOCK_SIZE)
251 
252 #if (EROFS_BLKSIZ % 4096 || !EROFS_BLKSIZ)
253 #error erofs cannot be used in this platform
254 #endif
255 
256 enum erofs_kmap_type {
257 	EROFS_NO_KMAP,		/* don't map the buffer */
258 	EROFS_KMAP,		/* use kmap() to map the buffer */
259 	EROFS_KMAP_ATOMIC,	/* use kmap_atomic() to map the buffer */
260 };
261 
262 struct erofs_buf {
263 	struct page *page;
264 	void *base;
265 	enum erofs_kmap_type kmap_type;
266 };
267 #define __EROFS_BUF_INITIALIZER	((struct erofs_buf){ .page = NULL })
268 
269 #define ROOT_NID(sb)		((sb)->root_nid)
270 
271 #define erofs_blknr(addr)       ((addr) / EROFS_BLKSIZ)
272 #define erofs_blkoff(addr)      ((addr) % EROFS_BLKSIZ)
273 #define blknr_to_addr(nr)       ((erofs_off_t)(nr) * EROFS_BLKSIZ)
274 
iloc(struct erofs_sb_info * sbi,erofs_nid_t nid)275 static inline erofs_off_t iloc(struct erofs_sb_info *sbi, erofs_nid_t nid)
276 {
277 	return blknr_to_addr(sbi->meta_blkaddr) + (nid << sbi->islotbits);
278 }
279 
280 #define EROFS_FEATURE_FUNCS(name, compat, feature) \
281 static inline bool erofs_sb_has_##name(struct erofs_sb_info *sbi) \
282 { \
283 	return sbi->feature_##compat & EROFS_FEATURE_##feature; \
284 }
285 
286 EROFS_FEATURE_FUNCS(zero_padding, incompat, INCOMPAT_ZERO_PADDING)
287 EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS)
288 EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER)
289 EROFS_FEATURE_FUNCS(chunked_file, incompat, INCOMPAT_CHUNKED_FILE)
290 EROFS_FEATURE_FUNCS(device_table, incompat, INCOMPAT_DEVICE_TABLE)
291 EROFS_FEATURE_FUNCS(compr_head2, incompat, INCOMPAT_COMPR_HEAD2)
292 EROFS_FEATURE_FUNCS(ztailpacking, incompat, INCOMPAT_ZTAILPACKING)
293 EROFS_FEATURE_FUNCS(fragments, incompat, INCOMPAT_FRAGMENTS)
294 EROFS_FEATURE_FUNCS(dedupe, incompat, INCOMPAT_DEDUPE)
295 EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
296 
297 /* atomic flag definitions */
298 #define EROFS_I_EA_INITED_BIT	0
299 #define EROFS_I_Z_INITED_BIT	1
300 
301 /* bitlock definitions (arranged in reverse order) */
302 #define EROFS_I_BL_XATTR_BIT	(BITS_PER_LONG - 1)
303 #define EROFS_I_BL_Z_BIT	(BITS_PER_LONG - 2)
304 
305 struct erofs_inode {
306 	erofs_nid_t nid;
307 
308 	/* atomic flags (including bitlocks) */
309 	unsigned long flags;
310 
311 	unsigned char datalayout;
312 	unsigned char inode_isize;
313 	unsigned short xattr_isize;
314 
315 	unsigned int xattr_shared_count;
316 	unsigned int *xattr_shared_xattrs;
317 
318 	union {
319 		erofs_blk_t raw_blkaddr;
320 		struct {
321 			unsigned short	chunkformat;
322 			unsigned char	chunkbits;
323 		};
324 #ifdef CONFIG_EROFS_FS_ZIP
325 		struct {
326 			unsigned short z_advise;
327 			unsigned char  z_algorithmtype[2];
328 			unsigned char  z_logical_clusterbits;
329 			unsigned long  z_tailextent_headlcn;
330 			union {
331 				struct {
332 					erofs_off_t    z_idataoff;
333 					unsigned short z_idata_size;
334 				};
335 				erofs_off_t z_fragmentoff;
336 			};
337 		};
338 #endif	/* CONFIG_EROFS_FS_ZIP */
339 	};
340 	/* the corresponding vfs inode */
341 	struct inode vfs_inode;
342 };
343 
344 #define EROFS_I(ptr)	\
345 	container_of(ptr, struct erofs_inode, vfs_inode)
346 
erofs_inode_datablocks(struct inode * inode)347 static inline unsigned long erofs_inode_datablocks(struct inode *inode)
348 {
349 	/* since i_size cannot be changed */
350 	return DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ);
351 }
352 
erofs_bitrange(unsigned int value,unsigned int bit,unsigned int bits)353 static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit,
354 					  unsigned int bits)
355 {
356 
357 	return (value >> bit) & ((1 << bits) - 1);
358 }
359 
360 
erofs_inode_version(unsigned int value)361 static inline unsigned int erofs_inode_version(unsigned int value)
362 {
363 	return erofs_bitrange(value, EROFS_I_VERSION_BIT,
364 			      EROFS_I_VERSION_BITS);
365 }
366 
erofs_inode_datalayout(unsigned int value)367 static inline unsigned int erofs_inode_datalayout(unsigned int value)
368 {
369 	return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT,
370 			      EROFS_I_DATALAYOUT_BITS);
371 }
372 
373 /*
374  * Different from grab_cache_page_nowait(), reclaiming is never triggered
375  * when allocating new pages.
376  */
377 static inline
erofs_grab_cache_page_nowait(struct address_space * mapping,pgoff_t index)378 struct page *erofs_grab_cache_page_nowait(struct address_space *mapping,
379 					  pgoff_t index)
380 {
381 	return pagecache_get_page(mapping, index,
382 			FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT,
383 			readahead_gfp_mask(mapping) & ~__GFP_RECLAIM);
384 }
385 
386 extern const struct super_operations erofs_sops;
387 extern struct file_system_type erofs_fs_type;
388 
389 extern const struct address_space_operations erofs_raw_access_aops;
390 extern const struct address_space_operations z_erofs_aops;
391 
392 enum {
393 	BH_Encoded = BH_PrivateStart,
394 	BH_FullMapped,
395 	BH_Fragment,
396 	BH_Partialref,
397 };
398 
399 /* Has a disk mapping */
400 #define EROFS_MAP_MAPPED	(1 << BH_Mapped)
401 /* Located in metadata (could be copied from bd_inode) */
402 #define EROFS_MAP_META		(1 << BH_Meta)
403 /* The extent is encoded */
404 #define EROFS_MAP_ENCODED	(1 << BH_Encoded)
405 /* The length of extent is full */
406 #define EROFS_MAP_FULL_MAPPED	(1 << BH_FullMapped)
407 /* Located in the special packed inode */
408 #define EROFS_MAP_FRAGMENT	(1 << BH_Fragment)
409 /* The extent refers to partial decompressed data */
410 #define EROFS_MAP_PARTIAL_REF	(1 << BH_Partialref)
411 
412 struct erofs_map_blocks {
413 	struct erofs_buf buf;
414 
415 	erofs_off_t m_pa, m_la;
416 	u64 m_plen, m_llen;
417 
418 	unsigned short m_deviceid;
419 	char m_algorithmformat;
420 	unsigned int m_flags;
421 };
422 
423 /* Flags used by erofs_map_blocks_flatmode() */
424 #define EROFS_GET_BLOCKS_RAW    0x0001
425 /*
426  * Used to get the exact decompressed length, e.g. fiemap (consider lookback
427  * approach instead if possible since it's more metadata lightweight.)
428  */
429 #define EROFS_GET_BLOCKS_FIEMAP	0x0002
430 /* Used to map the whole extent if non-negligible data is requested for LZMA */
431 #define EROFS_GET_BLOCKS_READMORE	0x0004
432 /* Used to map tail extent for tailpacking inline or fragment pcluster */
433 #define EROFS_GET_BLOCKS_FINDTAIL	0x0008
434 
435 enum {
436 	Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX,
437 	Z_EROFS_COMPRESSION_INTERLACED,
438 	Z_EROFS_COMPRESSION_RUNTIME_MAX
439 };
440 
441 /* zmap.c */
442 extern const struct iomap_ops z_erofs_iomap_report_ops;
443 
444 #ifdef CONFIG_EROFS_FS_ZIP
445 int z_erofs_fill_inode(struct inode *inode);
446 int z_erofs_map_blocks_iter(struct inode *inode,
447 			    struct erofs_map_blocks *map,
448 			    int flags);
449 #else
z_erofs_fill_inode(struct inode * inode)450 static inline int z_erofs_fill_inode(struct inode *inode) { return -EOPNOTSUPP; }
z_erofs_map_blocks_iter(struct inode * inode,struct erofs_map_blocks * map,int flags)451 static inline int z_erofs_map_blocks_iter(struct inode *inode,
452 					  struct erofs_map_blocks *map,
453 					  int flags)
454 {
455 	return -EOPNOTSUPP;
456 }
457 #endif	/* !CONFIG_EROFS_FS_ZIP */
458 
459 struct erofs_map_dev {
460 	struct erofs_fscache *m_fscache;
461 	struct block_device *m_bdev;
462 	struct dax_device *m_daxdev;
463 	u64 m_dax_part_off;
464 
465 	erofs_off_t m_pa;
466 	unsigned int m_deviceid;
467 };
468 
469 /* data.c */
470 extern const struct file_operations erofs_file_fops;
471 void erofs_unmap_metabuf(struct erofs_buf *buf);
472 void erofs_put_metabuf(struct erofs_buf *buf);
473 void *erofs_bread(struct erofs_buf *buf, struct inode *inode,
474 		  erofs_blk_t blkaddr, enum erofs_kmap_type type);
475 void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,
476 			 erofs_blk_t blkaddr, enum erofs_kmap_type type);
477 int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *dev);
478 int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
479 		 u64 start, u64 len);
480 int erofs_map_blocks(struct inode *inode,
481 		     struct erofs_map_blocks *map, int flags);
482 
483 /* inode.c */
erofs_inode_hash(erofs_nid_t nid)484 static inline unsigned long erofs_inode_hash(erofs_nid_t nid)
485 {
486 #if BITS_PER_LONG == 32
487 	return (nid >> 32) ^ (nid & 0xffffffff);
488 #else
489 	return nid;
490 #endif
491 }
492 
493 extern const struct inode_operations erofs_generic_iops;
494 extern const struct inode_operations erofs_symlink_iops;
495 extern const struct inode_operations erofs_fast_symlink_iops;
496 
497 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid);
498 int erofs_getattr(struct user_namespace *mnt_userns, const struct path *path,
499 		  struct kstat *stat, u32 request_mask,
500 		  unsigned int query_flags);
501 
502 /* namei.c */
503 extern const struct inode_operations erofs_dir_iops;
504 
505 int erofs_namei(struct inode *dir, const struct qstr *name,
506 		erofs_nid_t *nid, unsigned int *d_type);
507 
508 /* dir.c */
509 extern const struct file_operations erofs_dir_fops;
510 
erofs_vm_map_ram(struct page ** pages,unsigned int count)511 static inline void *erofs_vm_map_ram(struct page **pages, unsigned int count)
512 {
513 	int retried = 0;
514 
515 	while (1) {
516 		void *p = vm_map_ram(pages, count, -1);
517 
518 		/* retry two more times (totally 3 times) */
519 		if (p || ++retried >= 3)
520 			return p;
521 		vm_unmap_aliases();
522 	}
523 	return NULL;
524 }
525 
526 /* pcpubuf.c */
527 void *erofs_get_pcpubuf(unsigned int requiredpages);
528 void erofs_put_pcpubuf(void *ptr);
529 int erofs_pcpubuf_growsize(unsigned int nrpages);
530 void erofs_pcpubuf_init(void);
531 void erofs_pcpubuf_exit(void);
532 
533 /* sysfs.c */
534 int erofs_register_sysfs(struct super_block *sb);
535 void erofs_unregister_sysfs(struct super_block *sb);
536 int __init erofs_init_sysfs(void);
537 void erofs_exit_sysfs(void);
538 
539 /* utils.c / zdata.c */
540 struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp);
erofs_pagepool_add(struct page ** pagepool,struct page * page)541 static inline void erofs_pagepool_add(struct page **pagepool,
542 		struct page *page)
543 {
544 	set_page_private(page, (unsigned long)*pagepool);
545 	*pagepool = page;
546 }
547 void erofs_release_pages(struct page **pagepool);
548 
549 #ifdef CONFIG_EROFS_FS_ZIP
550 int erofs_workgroup_put(struct erofs_workgroup *grp);
551 struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb,
552 					     pgoff_t index);
553 struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb,
554 					       struct erofs_workgroup *grp);
555 void erofs_workgroup_free_rcu(struct erofs_workgroup *grp);
556 void erofs_shrinker_register(struct super_block *sb);
557 void erofs_shrinker_unregister(struct super_block *sb);
558 int __init erofs_init_shrinker(void);
559 void erofs_exit_shrinker(void);
560 int __init z_erofs_init_zip_subsystem(void);
561 void z_erofs_exit_zip_subsystem(void);
562 int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
563 				       struct erofs_workgroup *egrp);
564 int erofs_try_to_free_cached_page(struct page *page);
565 int z_erofs_load_lz4_config(struct super_block *sb,
566 			    struct erofs_super_block *dsb,
567 			    struct z_erofs_lz4_cfgs *lz4, int len);
568 #else
erofs_shrinker_register(struct super_block * sb)569 static inline void erofs_shrinker_register(struct super_block *sb) {}
erofs_shrinker_unregister(struct super_block * sb)570 static inline void erofs_shrinker_unregister(struct super_block *sb) {}
erofs_init_shrinker(void)571 static inline int erofs_init_shrinker(void) { return 0; }
erofs_exit_shrinker(void)572 static inline void erofs_exit_shrinker(void) {}
z_erofs_init_zip_subsystem(void)573 static inline int z_erofs_init_zip_subsystem(void) { return 0; }
z_erofs_exit_zip_subsystem(void)574 static inline void z_erofs_exit_zip_subsystem(void) {}
z_erofs_load_lz4_config(struct super_block * sb,struct erofs_super_block * dsb,struct z_erofs_lz4_cfgs * lz4,int len)575 static inline int z_erofs_load_lz4_config(struct super_block *sb,
576 				  struct erofs_super_block *dsb,
577 				  struct z_erofs_lz4_cfgs *lz4, int len)
578 {
579 	if (lz4 || dsb->u1.lz4_max_distance) {
580 		erofs_err(sb, "lz4 algorithm isn't enabled");
581 		return -EINVAL;
582 	}
583 	return 0;
584 }
585 #endif	/* !CONFIG_EROFS_FS_ZIP */
586 
587 #ifdef CONFIG_EROFS_FS_ZIP_LZMA
588 int z_erofs_lzma_init(void);
589 void z_erofs_lzma_exit(void);
590 int z_erofs_load_lzma_config(struct super_block *sb,
591 			     struct erofs_super_block *dsb,
592 			     struct z_erofs_lzma_cfgs *lzma, int size);
593 #else
z_erofs_lzma_init(void)594 static inline int z_erofs_lzma_init(void) { return 0; }
z_erofs_lzma_exit(void)595 static inline int z_erofs_lzma_exit(void) { return 0; }
z_erofs_load_lzma_config(struct super_block * sb,struct erofs_super_block * dsb,struct z_erofs_lzma_cfgs * lzma,int size)596 static inline int z_erofs_load_lzma_config(struct super_block *sb,
597 			     struct erofs_super_block *dsb,
598 			     struct z_erofs_lzma_cfgs *lzma, int size) {
599 	if (lzma) {
600 		erofs_err(sb, "lzma algorithm isn't enabled");
601 		return -EINVAL;
602 	}
603 	return 0;
604 }
605 #endif	/* !CONFIG_EROFS_FS_ZIP */
606 
607 /* flags for erofs_fscache_register_cookie() */
608 #define EROFS_REG_COOKIE_NEED_INODE	1
609 #define EROFS_REG_COOKIE_NEED_NOEXIST	2
610 
611 /* fscache.c */
612 #ifdef CONFIG_EROFS_FS_ONDEMAND
613 int erofs_fscache_register_fs(struct super_block *sb);
614 void erofs_fscache_unregister_fs(struct super_block *sb);
615 
616 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
617 						    char *name,
618 						    unsigned int flags);
619 void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache);
620 
621 extern const struct address_space_operations erofs_fscache_access_aops;
622 #else
erofs_fscache_register_fs(struct super_block * sb)623 static inline int erofs_fscache_register_fs(struct super_block *sb)
624 {
625 	return -EOPNOTSUPP;
626 }
erofs_fscache_unregister_fs(struct super_block * sb)627 static inline void erofs_fscache_unregister_fs(struct super_block *sb) {}
628 
629 static inline
erofs_fscache_register_cookie(struct super_block * sb,char * name,unsigned int flags)630 struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb,
631 						     char *name,
632 						     unsigned int flags)
633 {
634 	return ERR_PTR(-EOPNOTSUPP);
635 }
636 
erofs_fscache_unregister_cookie(struct erofs_fscache * fscache)637 static inline void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache)
638 {
639 }
640 #endif
641 
642 #define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */
643 
644 #endif	/* __EROFS_INTERNAL_H */
645