xref: /linux/fs/ext4/ext4.h (revision aaa44952bbd1d4db14a4d676bf9595bb5db7e7b0)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  ext4.h
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/include/linux/minix_fs.h
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  */
16 
17 #ifndef _EXT4_H
18 #define _EXT4_H
19 
20 #include <linux/types.h>
21 #include <linux/blkdev.h>
22 #include <linux/magic.h>
23 #include <linux/jbd2.h>
24 #include <linux/quota.h>
25 #include <linux/rwsem.h>
26 #include <linux/rbtree.h>
27 #include <linux/seqlock.h>
28 #include <linux/mutex.h>
29 #include <linux/timer.h>
30 #include <linux/wait.h>
31 #include <linux/sched/signal.h>
32 #include <linux/blockgroup_lock.h>
33 #include <linux/percpu_counter.h>
34 #include <linux/ratelimit.h>
35 #include <crypto/hash.h>
36 #include <linux/falloc.h>
37 #include <linux/percpu-rwsem.h>
38 #include <linux/fiemap.h>
39 #ifdef __KERNEL__
40 #include <linux/compat.h>
41 #endif
42 
43 #include <linux/fscrypt.h>
44 #include <linux/fsverity.h>
45 
46 #include <linux/compiler.h>
47 
48 /*
49  * The fourth extended filesystem constants/structures
50  */
51 
52 /*
53  * with AGGRESSIVE_CHECK allocator runs consistency checks over
54  * structures. these checks slow things down a lot
55  */
56 #define AGGRESSIVE_CHECK__
57 
58 /*
59  * with DOUBLE_CHECK defined mballoc creates persistent in-core
60  * bitmaps, maintains and uses them to check for double allocations
61  */
62 #define DOUBLE_CHECK__
63 
64 /*
65  * Define EXT4FS_DEBUG to produce debug messages
66  */
67 #undef EXT4FS_DEBUG
68 
69 /*
70  * Debug code
71  */
72 #ifdef EXT4FS_DEBUG
73 #define ext4_debug(f, a...)						\
74 	do {								\
75 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
76 			__FILE__, __LINE__, __func__);			\
77 		printk(KERN_DEBUG f, ## a);				\
78 	} while (0)
79 #else
80 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
81 #endif
82 
83  /*
84   * Turn on EXT_DEBUG to enable ext4_ext_show_path/leaf/move in extents.c
85   */
86 #define EXT_DEBUG__
87 
88 /*
89  * Dynamic printk for controlled extents debugging.
90  */
91 #ifdef CONFIG_EXT4_DEBUG
92 #define ext_debug(ino, fmt, ...)					\
93 	pr_debug("[%s/%d] EXT4-fs (%s): ino %lu: (%s, %d): %s:" fmt,	\
94 		 current->comm, task_pid_nr(current),			\
95 		 ino->i_sb->s_id, ino->i_ino, __FILE__, __LINE__,	\
96 		 __func__, ##__VA_ARGS__)
97 #else
98 #define ext_debug(ino, fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
99 #endif
100 
101 #define ASSERT(assert)						\
102 do {									\
103 	if (unlikely(!(assert))) {					\
104 		printk(KERN_EMERG					\
105 		       "Assertion failure in %s() at %s:%d: '%s'\n",	\
106 		       __func__, __FILE__, __LINE__, #assert);		\
107 		BUG();							\
108 	}								\
109 } while (0)
110 
111 /* data type for block offset of block group */
112 typedef int ext4_grpblk_t;
113 
114 /* data type for filesystem-wide blocks number */
115 typedef unsigned long long ext4_fsblk_t;
116 
117 /* data type for file logical block number */
118 typedef __u32 ext4_lblk_t;
119 
120 /* data type for block group number */
121 typedef unsigned int ext4_group_t;
122 
123 enum SHIFT_DIRECTION {
124 	SHIFT_LEFT = 0,
125 	SHIFT_RIGHT,
126 };
127 
128 /*
129  * Flags used in mballoc's allocation_context flags field.
130  *
131  * Also used to show what's going on for debugging purposes when the
132  * flag field is exported via the traceport interface
133  */
134 
135 /* prefer goal again. length */
136 #define EXT4_MB_HINT_MERGE		0x0001
137 /* blocks already reserved */
138 #define EXT4_MB_HINT_RESERVED		0x0002
139 /* metadata is being allocated */
140 #define EXT4_MB_HINT_METADATA		0x0004
141 /* first blocks in the file */
142 #define EXT4_MB_HINT_FIRST		0x0008
143 /* search for the best chunk */
144 #define EXT4_MB_HINT_BEST		0x0010
145 /* data is being allocated */
146 #define EXT4_MB_HINT_DATA		0x0020
147 /* don't preallocate (for tails) */
148 #define EXT4_MB_HINT_NOPREALLOC		0x0040
149 /* allocate for locality group */
150 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
151 /* allocate goal blocks or none */
152 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
153 /* goal is meaningful */
154 #define EXT4_MB_HINT_TRY_GOAL		0x0200
155 /* blocks already pre-reserved by delayed allocation */
156 #define EXT4_MB_DELALLOC_RESERVED	0x0400
157 /* We are doing stream allocation */
158 #define EXT4_MB_STREAM_ALLOC		0x0800
159 /* Use reserved root blocks if needed */
160 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
161 /* Use blocks from reserved pool */
162 #define EXT4_MB_USE_RESERVED		0x2000
163 /* Do strict check for free blocks while retrying block allocation */
164 #define EXT4_MB_STRICT_CHECK		0x4000
165 /* Large fragment size list lookup succeeded at least once for cr = 0 */
166 #define EXT4_MB_CR0_OPTIMIZED		0x8000
167 /* Avg fragment size rb tree lookup succeeded at least once for cr = 1 */
168 #define EXT4_MB_CR1_OPTIMIZED		0x00010000
169 /* Perform linear traversal for one group */
170 #define EXT4_MB_SEARCH_NEXT_LINEAR	0x00020000
171 struct ext4_allocation_request {
172 	/* target inode for block we're allocating */
173 	struct inode *inode;
174 	/* how many blocks we want to allocate */
175 	unsigned int len;
176 	/* logical block in target inode */
177 	ext4_lblk_t logical;
178 	/* the closest logical allocated block to the left */
179 	ext4_lblk_t lleft;
180 	/* the closest logical allocated block to the right */
181 	ext4_lblk_t lright;
182 	/* phys. target (a hint) */
183 	ext4_fsblk_t goal;
184 	/* phys. block for the closest logical allocated block to the left */
185 	ext4_fsblk_t pleft;
186 	/* phys. block for the closest logical allocated block to the right */
187 	ext4_fsblk_t pright;
188 	/* flags. see above EXT4_MB_HINT_* */
189 	unsigned int flags;
190 };
191 
192 /*
193  * Logical to physical block mapping, used by ext4_map_blocks()
194  *
195  * This structure is used to pass requests into ext4_map_blocks() as
196  * well as to store the information returned by ext4_map_blocks().  It
197  * takes less room on the stack than a struct buffer_head.
198  */
199 #define EXT4_MAP_NEW		BIT(BH_New)
200 #define EXT4_MAP_MAPPED		BIT(BH_Mapped)
201 #define EXT4_MAP_UNWRITTEN	BIT(BH_Unwritten)
202 #define EXT4_MAP_BOUNDARY	BIT(BH_Boundary)
203 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
204 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
205 
206 struct ext4_map_blocks {
207 	ext4_fsblk_t m_pblk;
208 	ext4_lblk_t m_lblk;
209 	unsigned int m_len;
210 	unsigned int m_flags;
211 };
212 
213 /*
214  * Block validity checking, system zone rbtree.
215  */
216 struct ext4_system_blocks {
217 	struct rb_root root;
218 	struct rcu_head rcu;
219 };
220 
221 /*
222  * Flags for ext4_io_end->flags
223  */
224 #define	EXT4_IO_END_UNWRITTEN	0x0001
225 
226 struct ext4_io_end_vec {
227 	struct list_head list;		/* list of io_end_vec */
228 	loff_t offset;			/* offset in the file */
229 	ssize_t size;			/* size of the extent */
230 };
231 
232 /*
233  * For converting unwritten extents on a work queue. 'handle' is used for
234  * buffered writeback.
235  */
236 typedef struct ext4_io_end {
237 	struct list_head	list;		/* per-file finished IO list */
238 	handle_t		*handle;	/* handle reserved for extent
239 						 * conversion */
240 	struct inode		*inode;		/* file being written to */
241 	struct bio		*bio;		/* Linked list of completed
242 						 * bios covering the extent */
243 	unsigned int		flag;		/* unwritten or not */
244 	atomic_t		count;		/* reference counter */
245 	struct list_head	list_vec;	/* list of ext4_io_end_vec */
246 } ext4_io_end_t;
247 
248 struct ext4_io_submit {
249 	struct writeback_control *io_wbc;
250 	struct bio		*io_bio;
251 	ext4_io_end_t		*io_end;
252 	sector_t		io_next_block;
253 };
254 
255 /*
256  * Special inodes numbers
257  */
258 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
259 #define EXT4_ROOT_INO		 2	/* Root inode */
260 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
261 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
262 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
263 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
264 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
265 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
266 
267 /* First non-reserved inode for old ext4 filesystems */
268 #define EXT4_GOOD_OLD_FIRST_INO	11
269 
270 /*
271  * Maximal count of links to a file
272  */
273 #define EXT4_LINK_MAX		65000
274 
275 /*
276  * Macro-instructions used to manage several block sizes
277  */
278 #define EXT4_MIN_BLOCK_SIZE		1024
279 #define	EXT4_MAX_BLOCK_SIZE		65536
280 #define EXT4_MIN_BLOCK_LOG_SIZE		10
281 #define EXT4_MAX_BLOCK_LOG_SIZE		16
282 #define EXT4_MAX_CLUSTER_LOG_SIZE	30
283 #ifdef __KERNEL__
284 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
285 #else
286 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
287 #endif
288 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
289 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
290 					 EXT4_SB(s)->s_cluster_bits)
291 #ifdef __KERNEL__
292 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
293 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
294 #else
295 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
296 #endif
297 #ifdef __KERNEL__
298 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
299 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
300 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
301 #else
302 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
303 				 EXT4_GOOD_OLD_INODE_SIZE : \
304 				 (s)->s_inode_size)
305 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
306 				 EXT4_GOOD_OLD_FIRST_INO : \
307 				 (s)->s_first_ino)
308 #endif
309 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
310 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
311 	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
312 								  blkbits))
313 
314 /* Translate a block number to a cluster number */
315 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
316 /* Translate a cluster number to a block number */
317 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
318 /* Translate # of blks to # of clusters */
319 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
320 				 (sbi)->s_cluster_bits)
321 /* Mask out the low bits to get the starting block of the cluster */
322 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
323 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
324 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
325 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
326 /* Fill in the low bits to get the last block of the cluster */
327 #define EXT4_LBLK_CFILL(sbi, lblk) ((lblk) |				\
328 				    ((ext4_lblk_t) (sbi)->s_cluster_ratio - 1))
329 /* Get the cluster offset */
330 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
331 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
332 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
333 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
334 
335 /*
336  * Structure of a blocks group descriptor
337  */
338 struct ext4_group_desc
339 {
340 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
341 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
342 	__le32	bg_inode_table_lo;	/* Inodes table block */
343 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
344 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
345 	__le16	bg_used_dirs_count_lo;	/* Directories count */
346 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
347 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
348 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
349 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
350 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
351 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
352 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
353 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
354 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
355 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
356 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
357 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
358 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
359 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
360 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
361 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
362 	__u32   bg_reserved;
363 };
364 
365 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
366 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
367 	 sizeof(__le16))
368 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
369 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
370 	 sizeof(__le16))
371 
372 /*
373  * Structure of a flex block group info
374  */
375 
376 struct flex_groups {
377 	atomic64_t	free_clusters;
378 	atomic_t	free_inodes;
379 	atomic_t	used_dirs;
380 };
381 
382 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
383 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
384 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
385 
386 /*
387  * Macro-instructions used to manage group descriptors
388  */
389 #define EXT4_MIN_DESC_SIZE		32
390 #define EXT4_MIN_DESC_SIZE_64BIT	64
391 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
392 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
393 #ifdef __KERNEL__
394 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
395 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
396 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
397 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
398 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
399 #else
400 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
401 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
402 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
403 #endif
404 
405 /*
406  * Constants relative to the data blocks
407  */
408 #define	EXT4_NDIR_BLOCKS		12
409 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
410 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
411 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
412 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
413 
414 /*
415  * Inode flags
416  */
417 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
418 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
419 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
420 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
421 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
422 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
423 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
424 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
425 /* Reserved for compression usage... */
426 #define EXT4_DIRTY_FL			0x00000100
427 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
428 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
429 	/* nb: was previously EXT2_ECOMPR_FL */
430 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
431 /* End compression flags --- maybe not all used */
432 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
433 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
434 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
435 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
436 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
437 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
438 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
439 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
440 #define EXT4_VERITY_FL			0x00100000 /* Verity protected inode */
441 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
442 /* 0x00400000 was formerly EXT4_EOFBLOCKS_FL */
443 
444 #define EXT4_DAX_FL			0x02000000 /* Inode is DAX */
445 
446 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
447 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
448 #define EXT4_CASEFOLD_FL		0x40000000 /* Casefolded directory */
449 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
450 
451 /* User modifiable flags */
452 #define EXT4_FL_USER_MODIFIABLE		(EXT4_SECRM_FL | \
453 					 EXT4_UNRM_FL | \
454 					 EXT4_COMPR_FL | \
455 					 EXT4_SYNC_FL | \
456 					 EXT4_IMMUTABLE_FL | \
457 					 EXT4_APPEND_FL | \
458 					 EXT4_NODUMP_FL | \
459 					 EXT4_NOATIME_FL | \
460 					 EXT4_JOURNAL_DATA_FL | \
461 					 EXT4_NOTAIL_FL | \
462 					 EXT4_DIRSYNC_FL | \
463 					 EXT4_TOPDIR_FL | \
464 					 EXT4_EXTENTS_FL | \
465 					 0x00400000 /* EXT4_EOFBLOCKS_FL */ | \
466 					 EXT4_DAX_FL | \
467 					 EXT4_PROJINHERIT_FL | \
468 					 EXT4_CASEFOLD_FL)
469 
470 /* User visible flags */
471 #define EXT4_FL_USER_VISIBLE		(EXT4_FL_USER_MODIFIABLE | \
472 					 EXT4_DIRTY_FL | \
473 					 EXT4_COMPRBLK_FL | \
474 					 EXT4_NOCOMPR_FL | \
475 					 EXT4_ENCRYPT_FL | \
476 					 EXT4_INDEX_FL | \
477 					 EXT4_VERITY_FL | \
478 					 EXT4_INLINE_DATA_FL)
479 
480 /* Flags that should be inherited by new inodes from their parent. */
481 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
482 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
483 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
484 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
485 			   EXT4_PROJINHERIT_FL | EXT4_CASEFOLD_FL |\
486 			   EXT4_DAX_FL)
487 
488 /* Flags that are appropriate for regular files (all but dir-specific ones). */
489 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL | EXT4_CASEFOLD_FL |\
490 			   EXT4_PROJINHERIT_FL))
491 
492 /* Flags that are appropriate for non-directories/regular files. */
493 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
494 
495 /* The only flags that should be swapped */
496 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
497 
498 /* Flags which are mutually exclusive to DAX */
499 #define EXT4_DAX_MUT_EXCL (EXT4_VERITY_FL | EXT4_ENCRYPT_FL |\
500 			   EXT4_JOURNAL_DATA_FL | EXT4_INLINE_DATA_FL)
501 
502 /* Mask out flags that are inappropriate for the given type of inode. */
503 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
504 {
505 	if (S_ISDIR(mode))
506 		return flags;
507 	else if (S_ISREG(mode))
508 		return flags & EXT4_REG_FLMASK;
509 	else
510 		return flags & EXT4_OTHER_FLMASK;
511 }
512 
513 /*
514  * Inode flags used for atomic set/get
515  */
516 enum {
517 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
518 	EXT4_INODE_UNRM		= 1,	/* Undelete */
519 	EXT4_INODE_COMPR	= 2,	/* Compress file */
520 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
521 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
522 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
523 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
524 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
525 /* Reserved for compression usage... */
526 	EXT4_INODE_DIRTY	= 8,
527 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
528 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
529 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
530 /* End compression flags --- maybe not all used */
531 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
532 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
533 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
534 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
535 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
536 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
537 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
538 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
539 	EXT4_INODE_VERITY	= 20,	/* Verity protected inode */
540 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
541 /* 22 was formerly EXT4_INODE_EOFBLOCKS */
542 	EXT4_INODE_DAX		= 25,	/* Inode is DAX */
543 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
544 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
545 	EXT4_INODE_CASEFOLD	= 30,	/* Casefolded directory */
546 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
547 };
548 
549 /*
550  * Since it's pretty easy to mix up bit numbers and hex values, we use a
551  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
552  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
553  * any extra space in the compiled kernel image, otherwise, the build will fail.
554  * It's important that these values are the same, since we are using
555  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
556  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
557  * values found in ext2, ext3 and ext4 filesystems, and of course the values
558  * defined in e2fsprogs.
559  *
560  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
561  */
562 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
563 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
564 
565 static inline void ext4_check_flag_values(void)
566 {
567 	CHECK_FLAG_VALUE(SECRM);
568 	CHECK_FLAG_VALUE(UNRM);
569 	CHECK_FLAG_VALUE(COMPR);
570 	CHECK_FLAG_VALUE(SYNC);
571 	CHECK_FLAG_VALUE(IMMUTABLE);
572 	CHECK_FLAG_VALUE(APPEND);
573 	CHECK_FLAG_VALUE(NODUMP);
574 	CHECK_FLAG_VALUE(NOATIME);
575 	CHECK_FLAG_VALUE(DIRTY);
576 	CHECK_FLAG_VALUE(COMPRBLK);
577 	CHECK_FLAG_VALUE(NOCOMPR);
578 	CHECK_FLAG_VALUE(ENCRYPT);
579 	CHECK_FLAG_VALUE(INDEX);
580 	CHECK_FLAG_VALUE(IMAGIC);
581 	CHECK_FLAG_VALUE(JOURNAL_DATA);
582 	CHECK_FLAG_VALUE(NOTAIL);
583 	CHECK_FLAG_VALUE(DIRSYNC);
584 	CHECK_FLAG_VALUE(TOPDIR);
585 	CHECK_FLAG_VALUE(HUGE_FILE);
586 	CHECK_FLAG_VALUE(EXTENTS);
587 	CHECK_FLAG_VALUE(VERITY);
588 	CHECK_FLAG_VALUE(EA_INODE);
589 	CHECK_FLAG_VALUE(INLINE_DATA);
590 	CHECK_FLAG_VALUE(PROJINHERIT);
591 	CHECK_FLAG_VALUE(CASEFOLD);
592 	CHECK_FLAG_VALUE(RESERVED);
593 }
594 
595 /* Used to pass group descriptor data when online resize is done */
596 struct ext4_new_group_input {
597 	__u32 group;		/* Group number for this data */
598 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
599 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
600 	__u64 inode_table;	/* Absolute block number of inode table start */
601 	__u32 blocks_count;	/* Total number of blocks in this group */
602 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
603 	__u16 unused;
604 };
605 
606 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
607 struct compat_ext4_new_group_input {
608 	u32 group;
609 	compat_u64 block_bitmap;
610 	compat_u64 inode_bitmap;
611 	compat_u64 inode_table;
612 	u32 blocks_count;
613 	u16 reserved_blocks;
614 	u16 unused;
615 };
616 #endif
617 
618 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
619 struct ext4_new_group_data {
620 	__u32 group;
621 	__u64 block_bitmap;
622 	__u64 inode_bitmap;
623 	__u64 inode_table;
624 	__u32 blocks_count;
625 	__u16 reserved_blocks;
626 	__u16 mdata_blocks;
627 	__u32 free_clusters_count;
628 };
629 
630 /* Indexes used to index group tables in ext4_new_group_data */
631 enum {
632 	BLOCK_BITMAP = 0,	/* block bitmap */
633 	INODE_BITMAP,		/* inode bitmap */
634 	INODE_TABLE,		/* inode tables */
635 	GROUP_TABLE_COUNT,
636 };
637 
638 /*
639  * Flags used by ext4_map_blocks()
640  */
641 	/* Allocate any needed blocks and/or convert an unwritten
642 	   extent to be an initialized ext4 */
643 #define EXT4_GET_BLOCKS_CREATE			0x0001
644 	/* Request the creation of an unwritten extent */
645 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
646 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
647 						 EXT4_GET_BLOCKS_CREATE)
648 	/* Caller is from the delayed allocation writeout path
649 	 * finally doing the actual allocation of delayed blocks */
650 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
651 	/* caller is from the direct IO path, request to creation of an
652 	unwritten extents if not allocated, split the unwritten
653 	extent if blocks has been preallocated already*/
654 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
655 #define EXT4_GET_BLOCKS_CONVERT			0x0010
656 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
657 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
658 	/* Convert extent to initialized after IO complete */
659 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
660 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
661 	/* Eventual metadata allocation (due to growing extent tree)
662 	 * should not fail, so try to use reserved blocks for that.*/
663 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
664 	/* Don't normalize allocation size (used for fallocate) */
665 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
666 	/* Convert written extents to unwritten */
667 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
668 	/* Write zeros to newly created written extents */
669 #define EXT4_GET_BLOCKS_ZERO			0x0200
670 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
671 					EXT4_GET_BLOCKS_ZERO)
672 	/* Caller will submit data before dropping transaction handle. This
673 	 * allows jbd2 to avoid submitting data before commit. */
674 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
675 
676 /*
677  * The bit position of these flags must not overlap with any of the
678  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
679  * read_extent_tree_block(), ext4_split_extent_at(),
680  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
681  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
682  * caching the extents when reading from the extent tree while a
683  * truncate or punch hole operation is in progress.
684  */
685 #define EXT4_EX_NOCACHE				0x40000000
686 #define EXT4_EX_FORCE_CACHE			0x20000000
687 #define EXT4_EX_NOFAIL				0x10000000
688 
689 /*
690  * Flags used by ext4_free_blocks
691  */
692 #define EXT4_FREE_BLOCKS_METADATA		0x0001
693 #define EXT4_FREE_BLOCKS_FORGET			0x0002
694 #define EXT4_FREE_BLOCKS_VALIDATED		0x0004
695 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE		0x0008
696 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
697 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
698 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
699 
700 /*
701  * ioctl commands
702  */
703 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
704 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
705 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
706 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
707 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
708 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
709 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
710 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
711 #define EXT4_IOC_MIGRATE		_IO('f', 9)
712  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
713  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
714 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
715 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
716 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
717 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
718 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
719 /* ioctl codes 19--39 are reserved for fscrypt */
720 #define EXT4_IOC_CLEAR_ES_CACHE		_IO('f', 40)
721 #define EXT4_IOC_GETSTATE		_IOW('f', 41, __u32)
722 #define EXT4_IOC_GET_ES_CACHE		_IOWR('f', 42, struct fiemap)
723 
724 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
725 
726 /*
727  * Flags for going down operation
728  */
729 #define EXT4_GOING_FLAGS_DEFAULT		0x0	/* going down */
730 #define EXT4_GOING_FLAGS_LOGFLUSH		0x1	/* flush log but not data */
731 #define EXT4_GOING_FLAGS_NOLOGFLUSH		0x2	/* don't flush log nor data */
732 
733 /*
734  * Flags returned by EXT4_IOC_GETSTATE
735  *
736  * We only expose to userspace a subset of the state flags in
737  * i_state_flags
738  */
739 #define EXT4_STATE_FLAG_EXT_PRECACHED	0x00000001
740 #define EXT4_STATE_FLAG_NEW		0x00000002
741 #define EXT4_STATE_FLAG_NEWENTRY	0x00000004
742 #define EXT4_STATE_FLAG_DA_ALLOC_CLOSE	0x00000008
743 
744 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
745 /*
746  * ioctl commands in 32 bit emulation
747  */
748 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
749 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
750 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
751 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
752 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
753 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
754 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
755 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
756 #endif
757 
758 /*
759  * Returned by EXT4_IOC_GET_ES_CACHE as an additional possible flag.
760  * It indicates that the entry in extent status cache is for a hole.
761  */
762 #define EXT4_FIEMAP_EXTENT_HOLE		0x08000000
763 
764 /* Max physical block we can address w/o extents */
765 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
766 
767 /* Max logical block we can support */
768 #define EXT4_MAX_LOGICAL_BLOCK		0xFFFFFFFE
769 
770 /*
771  * Structure of an inode on the disk
772  */
773 struct ext4_inode {
774 	__le16	i_mode;		/* File mode */
775 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
776 	__le32	i_size_lo;	/* Size in bytes */
777 	__le32	i_atime;	/* Access time */
778 	__le32	i_ctime;	/* Inode Change time */
779 	__le32	i_mtime;	/* Modification time */
780 	__le32	i_dtime;	/* Deletion Time */
781 	__le16	i_gid;		/* Low 16 bits of Group Id */
782 	__le16	i_links_count;	/* Links count */
783 	__le32	i_blocks_lo;	/* Blocks count */
784 	__le32	i_flags;	/* File flags */
785 	union {
786 		struct {
787 			__le32  l_i_version;
788 		} linux1;
789 		struct {
790 			__u32  h_i_translator;
791 		} hurd1;
792 		struct {
793 			__u32  m_i_reserved1;
794 		} masix1;
795 	} osd1;				/* OS dependent 1 */
796 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
797 	__le32	i_generation;	/* File version (for NFS) */
798 	__le32	i_file_acl_lo;	/* File ACL */
799 	__le32	i_size_high;
800 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
801 	union {
802 		struct {
803 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
804 			__le16	l_i_file_acl_high;
805 			__le16	l_i_uid_high;	/* these 2 fields */
806 			__le16	l_i_gid_high;	/* were reserved2[0] */
807 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
808 			__le16	l_i_reserved;
809 		} linux2;
810 		struct {
811 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
812 			__u16	h_i_mode_high;
813 			__u16	h_i_uid_high;
814 			__u16	h_i_gid_high;
815 			__u32	h_i_author;
816 		} hurd2;
817 		struct {
818 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
819 			__le16	m_i_file_acl_high;
820 			__u32	m_i_reserved2[2];
821 		} masix2;
822 	} osd2;				/* OS dependent 2 */
823 	__le16	i_extra_isize;
824 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
825 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
826 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
827 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
828 	__le32  i_crtime;       /* File Creation time */
829 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
830 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
831 	__le32	i_projid;	/* Project ID */
832 };
833 
834 struct move_extent {
835 	__u32 reserved;		/* should be zero */
836 	__u32 donor_fd;		/* donor file descriptor */
837 	__u64 orig_start;	/* logical start offset in block for orig */
838 	__u64 donor_start;	/* logical start offset in block for donor */
839 	__u64 len;		/* block length to be moved */
840 	__u64 moved_len;	/* moved block length */
841 };
842 
843 #define EXT4_EPOCH_BITS 2
844 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
845 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
846 
847 /*
848  * Extended fields will fit into an inode if the filesystem was formatted
849  * with large inodes (-I 256 or larger) and there are not currently any EAs
850  * consuming all of the available space. For new inodes we always reserve
851  * enough space for the kernel's known extended fields, but for inodes
852  * created with an old kernel this might not have been the case. None of
853  * the extended inode fields is critical for correct filesystem operation.
854  * This macro checks if a certain field fits in the inode. Note that
855  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
856  */
857 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
858 	((offsetof(typeof(*ext4_inode), field) +	\
859 	  sizeof((ext4_inode)->field))			\
860 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
861 	    (einode)->i_extra_isize))			\
862 
863 /*
864  * We use an encoding that preserves the times for extra epoch "00":
865  *
866  * extra  msb of                         adjust for signed
867  * epoch  32-bit                         32-bit tv_sec to
868  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
869  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
870  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
871  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
872  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
873  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
874  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
875  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
876  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
877  *
878  * Note that previous versions of the kernel on 64-bit systems would
879  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
880  * 1970.  e2fsck will correct this, assuming that it is run on the
881  * affected filesystem before 2242.
882  */
883 
884 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
885 {
886 	u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
887 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
888 }
889 
890 static inline void ext4_decode_extra_time(struct timespec64 *time,
891 					  __le32 extra)
892 {
893 	if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK)))
894 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
895 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
896 }
897 
898 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)				\
899 do {										\
900 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
901 		(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	\
902 		(raw_inode)->xtime ## _extra =					\
903 				ext4_encode_extra_time(&(inode)->xtime);	\
904 		}								\
905 	else	\
906 		(raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (inode)->xtime.tv_sec, S32_MIN, S32_MAX));	\
907 } while (0)
908 
909 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
910 do {									       \
911 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
912 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
913 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
914 		(raw_inode)->xtime ## _extra =				       \
915 				ext4_encode_extra_time(&(einode)->xtime);      \
916 } while (0)
917 
918 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)				\
919 do {										\
920 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);	\
921 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {	\
922 		ext4_decode_extra_time(&(inode)->xtime,				\
923 				       raw_inode->xtime ## _extra);		\
924 		}								\
925 	else									\
926 		(inode)->xtime.tv_nsec = 0;					\
927 } while (0)
928 
929 
930 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
931 do {									       \
932 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
933 		(einode)->xtime.tv_sec = 				       \
934 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
935 	else								       \
936 		(einode)->xtime.tv_sec = 0;				       \
937 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
938 		ext4_decode_extra_time(&(einode)->xtime,		       \
939 				       raw_inode->xtime ## _extra);	       \
940 	else								       \
941 		(einode)->xtime.tv_nsec = 0;				       \
942 } while (0)
943 
944 #define i_disk_version osd1.linux1.l_i_version
945 
946 #if defined(__KERNEL__) || defined(__linux__)
947 #define i_reserved1	osd1.linux1.l_i_reserved1
948 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
949 #define i_blocks_high	osd2.linux2.l_i_blocks_high
950 #define i_uid_low	i_uid
951 #define i_gid_low	i_gid
952 #define i_uid_high	osd2.linux2.l_i_uid_high
953 #define i_gid_high	osd2.linux2.l_i_gid_high
954 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
955 
956 #elif defined(__GNU__)
957 
958 #define i_translator	osd1.hurd1.h_i_translator
959 #define i_uid_high	osd2.hurd2.h_i_uid_high
960 #define i_gid_high	osd2.hurd2.h_i_gid_high
961 #define i_author	osd2.hurd2.h_i_author
962 
963 #elif defined(__masix__)
964 
965 #define i_reserved1	osd1.masix1.m_i_reserved1
966 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
967 #define i_reserved2	osd2.masix2.m_i_reserved2
968 
969 #endif /* defined(__KERNEL__) || defined(__linux__) */
970 
971 #include "extents_status.h"
972 #include "fast_commit.h"
973 
974 /*
975  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
976  *
977  * These are needed to avoid lockdep false positives when we need to
978  * allocate blocks to the quota inode during ext4_map_blocks(), while
979  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
980  * do quota tracking for the quota inode, this avoids deadlock (as
981  * well as infinite recursion, since it isn't turtles all the way
982  * down...)
983  *
984  *  I_DATA_SEM_NORMAL - Used for most inodes
985  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
986  *			  where the second inode has larger inode number
987  *			  than the first
988  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
989  */
990 enum {
991 	I_DATA_SEM_NORMAL = 0,
992 	I_DATA_SEM_OTHER,
993 	I_DATA_SEM_QUOTA,
994 };
995 
996 
997 /*
998  * fourth extended file system inode data in memory
999  */
1000 struct ext4_inode_info {
1001 	__le32	i_data[15];	/* unconverted */
1002 	__u32	i_dtime;
1003 	ext4_fsblk_t	i_file_acl;
1004 
1005 	/*
1006 	 * i_block_group is the number of the block group which contains
1007 	 * this file's inode.  Constant across the lifetime of the inode,
1008 	 * it is used for making block allocation decisions - we try to
1009 	 * place a file's data blocks near its inode block, and new inodes
1010 	 * near to their parent directory's inode.
1011 	 */
1012 	ext4_group_t	i_block_group;
1013 	ext4_lblk_t	i_dir_start_lookup;
1014 #if (BITS_PER_LONG < 64)
1015 	unsigned long	i_state_flags;		/* Dynamic state flags */
1016 #endif
1017 	unsigned long	i_flags;
1018 
1019 	/*
1020 	 * Extended attributes can be read independently of the main file
1021 	 * data. Taking i_mutex even when reading would cause contention
1022 	 * between readers of EAs and writers of regular file data, so
1023 	 * instead we synchronize on xattr_sem when reading or changing
1024 	 * EAs.
1025 	 */
1026 	struct rw_semaphore xattr_sem;
1027 
1028 	struct list_head i_orphan;	/* unlinked but open inodes */
1029 
1030 	/* Fast commit related info */
1031 
1032 	struct list_head i_fc_list;	/*
1033 					 * inodes that need fast commit
1034 					 * protected by sbi->s_fc_lock.
1035 					 */
1036 
1037 	/* Start of lblk range that needs to be committed in this fast commit */
1038 	ext4_lblk_t i_fc_lblk_start;
1039 
1040 	/* End of lblk range that needs to be committed in this fast commit */
1041 	ext4_lblk_t i_fc_lblk_len;
1042 
1043 	/* Number of ongoing updates on this inode */
1044 	atomic_t  i_fc_updates;
1045 
1046 	/* Fast commit wait queue for this inode */
1047 	wait_queue_head_t i_fc_wait;
1048 
1049 	/* Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len */
1050 	struct mutex i_fc_lock;
1051 
1052 	/*
1053 	 * i_disksize keeps track of what the inode size is ON DISK, not
1054 	 * in memory.  During truncate, i_size is set to the new size by
1055 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
1056 	 * set i_disksize to 0 until the truncate is actually under way.
1057 	 *
1058 	 * The intent is that i_disksize always represents the blocks which
1059 	 * are used by this file.  This allows recovery to restart truncate
1060 	 * on orphans if we crash during truncate.  We actually write i_disksize
1061 	 * into the on-disk inode when writing inodes out, instead of i_size.
1062 	 *
1063 	 * The only time when i_disksize and i_size may be different is when
1064 	 * a truncate is in progress.  The only things which change i_disksize
1065 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
1066 	 */
1067 	loff_t	i_disksize;
1068 
1069 	/*
1070 	 * i_data_sem is for serialising ext4_truncate() against
1071 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
1072 	 * data tree are chopped off during truncate. We can't do that in
1073 	 * ext4 because whenever we perform intermediate commits during
1074 	 * truncate, the inode and all the metadata blocks *must* be in a
1075 	 * consistent state which allows truncation of the orphans to restart
1076 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
1077 	 * by other means, so we have i_data_sem.
1078 	 */
1079 	struct rw_semaphore i_data_sem;
1080 	/*
1081 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
1082 	 * operations. We have to make sure that new page cannot be faulted in
1083 	 * a section of the inode that is being punched. We cannot easily use
1084 	 * i_data_sem for this since we need protection for the whole punch
1085 	 * operation and i_data_sem ranks below transaction start so we have
1086 	 * to occasionally drop it.
1087 	 */
1088 	struct rw_semaphore i_mmap_sem;
1089 	struct inode vfs_inode;
1090 	struct jbd2_inode *jinode;
1091 
1092 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
1093 
1094 	/*
1095 	 * File creation time. Its function is same as that of
1096 	 * struct timespec64 i_{a,c,m}time in the generic inode.
1097 	 */
1098 	struct timespec64 i_crtime;
1099 
1100 	/* mballoc */
1101 	atomic_t i_prealloc_active;
1102 	struct list_head i_prealloc_list;
1103 	spinlock_t i_prealloc_lock;
1104 
1105 	/* extents status tree */
1106 	struct ext4_es_tree i_es_tree;
1107 	rwlock_t i_es_lock;
1108 	struct list_head i_es_list;
1109 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1110 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1111 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1112 					   extents to shrink. Protected by
1113 					   i_es_lock  */
1114 
1115 	/* ialloc */
1116 	ext4_group_t	i_last_alloc_group;
1117 
1118 	/* allocation reservation info for delalloc */
1119 	/* In case of bigalloc, this refer to clusters rather than blocks */
1120 	unsigned int i_reserved_data_blocks;
1121 
1122 	/* pending cluster reservations for bigalloc file systems */
1123 	struct ext4_pending_tree i_pending_tree;
1124 
1125 	/* on-disk additional length */
1126 	__u16 i_extra_isize;
1127 
1128 	/* Indicate the inline data space. */
1129 	u16 i_inline_off;
1130 	u16 i_inline_size;
1131 
1132 #ifdef CONFIG_QUOTA
1133 	/* quota space reservation, managed internally by quota code */
1134 	qsize_t i_reserved_quota;
1135 #endif
1136 
1137 	/* Lock protecting lists below */
1138 	spinlock_t i_completed_io_lock;
1139 	/*
1140 	 * Completed IOs that need unwritten extents handling and have
1141 	 * transaction reserved
1142 	 */
1143 	struct list_head i_rsv_conversion_list;
1144 	struct work_struct i_rsv_conversion_work;
1145 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1146 
1147 	spinlock_t i_block_reservation_lock;
1148 
1149 	/*
1150 	 * Transactions that contain inode's metadata needed to complete
1151 	 * fsync and fdatasync, respectively.
1152 	 */
1153 	tid_t i_sync_tid;
1154 	tid_t i_datasync_tid;
1155 
1156 #ifdef CONFIG_QUOTA
1157 	struct dquot *i_dquot[MAXQUOTAS];
1158 #endif
1159 
1160 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1161 	__u32 i_csum_seed;
1162 
1163 	kprojid_t i_projid;
1164 };
1165 
1166 /*
1167  * File system states
1168  */
1169 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1170 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1171 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1172 #define EXT4_FC_REPLAY			0x0020	/* Fast commit replay ongoing */
1173 
1174 /*
1175  * Misc. filesystem flags
1176  */
1177 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1178 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1179 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1180 
1181 /*
1182  * Mount flags set via mount options or defaults
1183  */
1184 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1185 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1186 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1187 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1188 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1189 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1190 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1191 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1192 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1193 #ifdef CONFIG_FS_DAX
1194 #define EXT4_MOUNT_DAX_ALWAYS		0x00200	/* Direct Access */
1195 #else
1196 #define EXT4_MOUNT_DAX_ALWAYS		0
1197 #endif
1198 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1199 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1200 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1201 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1202 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1203 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1204 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1205 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1206 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1207 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1208 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1209 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1210 						 * enable enforcement for hidden
1211 						 * quota files */
1212 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1213 						  * enforcement for hidden quota
1214 						  * files */
1215 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1216 						  * enforcement */
1217 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1218 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1219 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1220 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
1221 #define EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS 0x4000000
1222 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1223 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1224 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1225 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1226 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1227 
1228 /*
1229  * Mount flags set either automatically (could not be set by mount option)
1230  * based on per file system feature or property or in special cases such as
1231  * distinguishing between explicit mount option definition and default.
1232  */
1233 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1234 						      specified delalloc */
1235 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1236 						      size of blocksize * 8
1237 						      blocks */
1238 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1239 						      file systems */
1240 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1241 						specified journal checksum */
1242 
1243 #define EXT4_MOUNT2_JOURNAL_FAST_COMMIT	0x00000010 /* Journal fast commit */
1244 #define EXT4_MOUNT2_DAX_NEVER		0x00000020 /* Do not allow Direct Access */
1245 #define EXT4_MOUNT2_DAX_INODE		0x00000040 /* For printing options only */
1246 #define EXT4_MOUNT2_MB_OPTIMIZE_SCAN	0x00000080 /* Optimize group
1247 						    * scanning in mballoc
1248 						    */
1249 
1250 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1251 						~EXT4_MOUNT_##opt
1252 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1253 						EXT4_MOUNT_##opt
1254 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1255 					 EXT4_MOUNT_##opt)
1256 
1257 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1258 						~EXT4_MOUNT2_##opt
1259 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1260 						EXT4_MOUNT2_##opt
1261 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1262 					 EXT4_MOUNT2_##opt)
1263 
1264 #define ext4_test_and_set_bit		__test_and_set_bit_le
1265 #define ext4_set_bit			__set_bit_le
1266 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1267 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1268 #define ext4_clear_bit			__clear_bit_le
1269 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1270 #define ext4_test_bit			test_bit_le
1271 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1272 #define ext4_find_next_bit		find_next_bit_le
1273 
1274 extern void ext4_set_bits(void *bm, int cur, int len);
1275 
1276 /*
1277  * Maximal mount counts between two filesystem checks
1278  */
1279 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1280 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1281 
1282 /*
1283  * Behaviour when detecting errors
1284  */
1285 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1286 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1287 #define EXT4_ERRORS_PANIC		3	/* Panic */
1288 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1289 
1290 /* Metadata checksum algorithm codes */
1291 #define EXT4_CRC32C_CHKSUM		1
1292 
1293 /*
1294  * Structure of the super block
1295  */
1296 struct ext4_super_block {
1297 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1298 	__le32	s_blocks_count_lo;	/* Blocks count */
1299 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1300 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1301 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1302 	__le32	s_first_data_block;	/* First Data Block */
1303 	__le32	s_log_block_size;	/* Block size */
1304 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1305 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1306 	__le32	s_clusters_per_group;	/* # Clusters per group */
1307 	__le32	s_inodes_per_group;	/* # Inodes per group */
1308 	__le32	s_mtime;		/* Mount time */
1309 /*30*/	__le32	s_wtime;		/* Write time */
1310 	__le16	s_mnt_count;		/* Mount count */
1311 	__le16	s_max_mnt_count;	/* Maximal mount count */
1312 	__le16	s_magic;		/* Magic signature */
1313 	__le16	s_state;		/* File system state */
1314 	__le16	s_errors;		/* Behaviour when detecting errors */
1315 	__le16	s_minor_rev_level;	/* minor revision level */
1316 /*40*/	__le32	s_lastcheck;		/* time of last check */
1317 	__le32	s_checkinterval;	/* max. time between checks */
1318 	__le32	s_creator_os;		/* OS */
1319 	__le32	s_rev_level;		/* Revision level */
1320 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1321 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1322 	/*
1323 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1324 	 *
1325 	 * Note: the difference between the compatible feature set and
1326 	 * the incompatible feature set is that if there is a bit set
1327 	 * in the incompatible feature set that the kernel doesn't
1328 	 * know about, it should refuse to mount the filesystem.
1329 	 *
1330 	 * e2fsck's requirements are more strict; if it doesn't know
1331 	 * about a feature in either the compatible or incompatible
1332 	 * feature set, it must abort and not try to meddle with
1333 	 * things it doesn't understand...
1334 	 */
1335 	__le32	s_first_ino;		/* First non-reserved inode */
1336 	__le16  s_inode_size;		/* size of inode structure */
1337 	__le16	s_block_group_nr;	/* block group # of this superblock */
1338 	__le32	s_feature_compat;	/* compatible feature set */
1339 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1340 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1341 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1342 /*78*/	char	s_volume_name[16];	/* volume name */
1343 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
1344 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1345 	/*
1346 	 * Performance hints.  Directory preallocation should only
1347 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1348 	 */
1349 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1350 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1351 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1352 	/*
1353 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1354 	 */
1355 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1356 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1357 	__le32	s_journal_dev;		/* device number of journal file */
1358 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1359 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1360 	__u8	s_def_hash_version;	/* Default hash version to use */
1361 	__u8	s_jnl_backup_type;
1362 	__le16  s_desc_size;		/* size of group descriptor */
1363 /*100*/	__le32	s_default_mount_opts;
1364 	__le32	s_first_meta_bg;	/* First metablock block group */
1365 	__le32	s_mkfs_time;		/* When the filesystem was created */
1366 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1367 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1368 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1369 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1370 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1371 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1372 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1373 	__le32	s_flags;		/* Miscellaneous flags */
1374 	__le16  s_raid_stride;		/* RAID stride */
1375 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1376 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1377 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1378 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1379 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1380 	__u8	s_encryption_level;	/* versioning level for encryption */
1381 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1382 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1383 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1384 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1385 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1386 					      snapshot's future use */
1387 	__le32	s_snapshot_list;	/* inode number of the head of the
1388 					   on-disk snapshot list */
1389 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1390 	__le32	s_error_count;		/* number of fs errors */
1391 	__le32	s_first_error_time;	/* first time an error happened */
1392 	__le32	s_first_error_ino;	/* inode involved in first error */
1393 	__le64	s_first_error_block;	/* block involved of first error */
1394 	__u8	s_first_error_func[32] __nonstring;	/* function where the error happened */
1395 	__le32	s_first_error_line;	/* line number where error happened */
1396 	__le32	s_last_error_time;	/* most recent time of an error */
1397 	__le32	s_last_error_ino;	/* inode involved in last error */
1398 	__le32	s_last_error_line;	/* line number where error happened */
1399 	__le64	s_last_error_block;	/* block involved of last error */
1400 	__u8	s_last_error_func[32] __nonstring;	/* function where the error happened */
1401 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1402 	__u8	s_mount_opts[64];
1403 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1404 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1405 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1406 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1407 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1408 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1409 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1410 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1411 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1412 	__u8	s_wtime_hi;
1413 	__u8	s_mtime_hi;
1414 	__u8	s_mkfs_time_hi;
1415 	__u8	s_lastcheck_hi;
1416 	__u8	s_first_error_time_hi;
1417 	__u8	s_last_error_time_hi;
1418 	__u8	s_first_error_errcode;
1419 	__u8    s_last_error_errcode;
1420 	__le16  s_encoding;		/* Filename charset encoding */
1421 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
1422 	__le32	s_reserved[95];		/* Padding to the end of the block */
1423 	__le32	s_checksum;		/* crc32c(superblock) */
1424 };
1425 
1426 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1427 
1428 #ifdef __KERNEL__
1429 
1430 #ifdef CONFIG_FS_ENCRYPTION
1431 #define DUMMY_ENCRYPTION_ENABLED(sbi) ((sbi)->s_dummy_enc_policy.policy != NULL)
1432 #else
1433 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1434 #endif
1435 
1436 /* Number of quota types we support */
1437 #define EXT4_MAXQUOTAS 3
1438 
1439 #define EXT4_ENC_UTF8_12_1	1
1440 
1441 /*
1442  * fourth extended-fs super-block data in memory
1443  */
1444 struct ext4_sb_info {
1445 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1446 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1447 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1448 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1449 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1450 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1451 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1452 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1453 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1454 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1455 	unsigned long s_overhead;  /* # of fs overhead clusters */
1456 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1457 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1458 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1459 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1460 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1461 	struct buffer_head * __rcu *s_group_desc;
1462 	unsigned int s_mount_opt;
1463 	unsigned int s_mount_opt2;
1464 	unsigned long s_mount_flags;
1465 	unsigned int s_def_mount_opt;
1466 	ext4_fsblk_t s_sb_block;
1467 	atomic64_t s_resv_clusters;
1468 	kuid_t s_resuid;
1469 	kgid_t s_resgid;
1470 	unsigned short s_mount_state;
1471 	unsigned short s_pad;
1472 	int s_addr_per_block_bits;
1473 	int s_desc_per_block_bits;
1474 	int s_inode_size;
1475 	int s_first_ino;
1476 	unsigned int s_inode_readahead_blks;
1477 	unsigned int s_inode_goal;
1478 	u32 s_hash_seed[4];
1479 	int s_def_hash_version;
1480 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1481 	struct percpu_counter s_freeclusters_counter;
1482 	struct percpu_counter s_freeinodes_counter;
1483 	struct percpu_counter s_dirs_counter;
1484 	struct percpu_counter s_dirtyclusters_counter;
1485 	struct percpu_counter s_sra_exceeded_retry_limit;
1486 	struct blockgroup_lock *s_blockgroup_lock;
1487 	struct proc_dir_entry *s_proc;
1488 	struct kobject s_kobj;
1489 	struct completion s_kobj_unregister;
1490 	struct super_block *s_sb;
1491 
1492 	/* Journaling */
1493 	struct journal_s *s_journal;
1494 	struct list_head s_orphan;
1495 	struct mutex s_orphan_lock;
1496 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1497 	unsigned long s_commit_interval;
1498 	u32 s_max_batch_time;
1499 	u32 s_min_batch_time;
1500 	struct block_device *s_journal_bdev;
1501 #ifdef CONFIG_QUOTA
1502 	/* Names of quota files with journalled quota */
1503 	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1504 	int s_jquota_fmt;			/* Format of quota to use */
1505 #endif
1506 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1507 	struct ext4_system_blocks __rcu *s_system_blks;
1508 
1509 #ifdef EXTENTS_STATS
1510 	/* ext4 extents stats */
1511 	unsigned long s_ext_min;
1512 	unsigned long s_ext_max;
1513 	unsigned long s_depth_max;
1514 	spinlock_t s_ext_stats_lock;
1515 	unsigned long s_ext_blocks;
1516 	unsigned long s_ext_extents;
1517 #endif
1518 
1519 	/* for buddy allocator */
1520 	struct ext4_group_info ** __rcu *s_group_info;
1521 	struct inode *s_buddy_cache;
1522 	spinlock_t s_md_lock;
1523 	unsigned short *s_mb_offsets;
1524 	unsigned int *s_mb_maxs;
1525 	unsigned int s_group_info_size;
1526 	unsigned int s_mb_free_pending;
1527 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1528 						   after commit completed */
1529 	struct rb_root s_mb_avg_fragment_size_root;
1530 	rwlock_t s_mb_rb_lock;
1531 	struct list_head *s_mb_largest_free_orders;
1532 	rwlock_t *s_mb_largest_free_orders_locks;
1533 
1534 	/* tunables */
1535 	unsigned long s_stripe;
1536 	unsigned int s_mb_max_linear_groups;
1537 	unsigned int s_mb_stream_request;
1538 	unsigned int s_mb_max_to_scan;
1539 	unsigned int s_mb_min_to_scan;
1540 	unsigned int s_mb_stats;
1541 	unsigned int s_mb_order2_reqs;
1542 	unsigned int s_mb_group_prealloc;
1543 	unsigned int s_mb_max_inode_prealloc;
1544 	unsigned int s_max_dir_size_kb;
1545 	/* where last allocation was done - for stream allocation */
1546 	unsigned long s_mb_last_group;
1547 	unsigned long s_mb_last_start;
1548 	unsigned int s_mb_prefetch;
1549 	unsigned int s_mb_prefetch_limit;
1550 
1551 	/* stats for buddy allocator */
1552 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1553 	atomic_t s_bal_success;	/* we found long enough chunks */
1554 	atomic_t s_bal_allocated;	/* in blocks */
1555 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1556 	atomic_t s_bal_groups_scanned;	/* number of groups scanned */
1557 	atomic_t s_bal_goals;	/* goal hits */
1558 	atomic_t s_bal_breaks;	/* too long searches */
1559 	atomic_t s_bal_2orders;	/* 2^order hits */
1560 	atomic_t s_bal_cr0_bad_suggestions;
1561 	atomic_t s_bal_cr1_bad_suggestions;
1562 	atomic64_t s_bal_cX_groups_considered[4];
1563 	atomic64_t s_bal_cX_hits[4];
1564 	atomic64_t s_bal_cX_failed[4];		/* cX loop didn't find blocks */
1565 	atomic_t s_mb_buddies_generated;	/* number of buddies generated */
1566 	atomic64_t s_mb_generation_time;
1567 	atomic_t s_mb_lost_chunks;
1568 	atomic_t s_mb_preallocated;
1569 	atomic_t s_mb_discarded;
1570 	atomic_t s_lock_busy;
1571 
1572 	/* locality groups */
1573 	struct ext4_locality_group __percpu *s_locality_groups;
1574 
1575 	/* for write statistics */
1576 	unsigned long s_sectors_written_start;
1577 	u64 s_kbytes_written;
1578 
1579 	/* the size of zero-out chunk */
1580 	unsigned int s_extent_max_zeroout_kb;
1581 
1582 	unsigned int s_log_groups_per_flex;
1583 	struct flex_groups * __rcu *s_flex_groups;
1584 	ext4_group_t s_flex_groups_allocated;
1585 
1586 	/* workqueue for reserved extent conversions (buffered io) */
1587 	struct workqueue_struct *rsv_conversion_wq;
1588 
1589 	/* timer for periodic error stats printing */
1590 	struct timer_list s_err_report;
1591 
1592 	/* Lazy inode table initialization info */
1593 	struct ext4_li_request *s_li_request;
1594 	/* Wait multiplier for lazy initialization thread */
1595 	unsigned int s_li_wait_mult;
1596 
1597 	/* Kernel thread for multiple mount protection */
1598 	struct task_struct *s_mmp_tsk;
1599 
1600 	/* record the last minlen when FITRIM is called. */
1601 	atomic_t s_last_trim_minblks;
1602 
1603 	/* Reference to checksum algorithm driver via cryptoapi */
1604 	struct crypto_shash *s_chksum_driver;
1605 
1606 	/* Precomputed FS UUID checksum for seeding other checksums */
1607 	__u32 s_csum_seed;
1608 
1609 	/* Reclaim extents from extent status tree */
1610 	struct shrinker s_es_shrinker;
1611 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1612 	long s_es_nr_inode;
1613 	struct ext4_es_stats s_es_stats;
1614 	struct mb_cache *s_ea_block_cache;
1615 	struct mb_cache *s_ea_inode_cache;
1616 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1617 
1618 	/* Ratelimit ext4 messages. */
1619 	struct ratelimit_state s_err_ratelimit_state;
1620 	struct ratelimit_state s_warning_ratelimit_state;
1621 	struct ratelimit_state s_msg_ratelimit_state;
1622 	atomic_t s_warning_count;
1623 	atomic_t s_msg_count;
1624 
1625 	/* Encryption policy for '-o test_dummy_encryption' */
1626 	struct fscrypt_dummy_policy s_dummy_enc_policy;
1627 
1628 	/*
1629 	 * Barrier between writepages ops and changing any inode's JOURNAL_DATA
1630 	 * or EXTENTS flag.
1631 	 */
1632 	struct percpu_rw_semaphore s_writepages_rwsem;
1633 	struct dax_device *s_daxdev;
1634 #ifdef CONFIG_EXT4_DEBUG
1635 	unsigned long s_simulate_fail;
1636 #endif
1637 	/* Record the errseq of the backing block device */
1638 	errseq_t s_bdev_wb_err;
1639 	spinlock_t s_bdev_wb_lock;
1640 
1641 	/* Information about errors that happened during this mount */
1642 	spinlock_t s_error_lock;
1643 	int s_add_error_count;
1644 	int s_first_error_code;
1645 	__u32 s_first_error_line;
1646 	__u32 s_first_error_ino;
1647 	__u64 s_first_error_block;
1648 	const char *s_first_error_func;
1649 	time64_t s_first_error_time;
1650 	int s_last_error_code;
1651 	__u32 s_last_error_line;
1652 	__u32 s_last_error_ino;
1653 	__u64 s_last_error_block;
1654 	const char *s_last_error_func;
1655 	time64_t s_last_error_time;
1656 	/*
1657 	 * If we are in a context where we cannot update error information in
1658 	 * the on-disk superblock, we queue this work to do it.
1659 	 */
1660 	struct work_struct s_error_work;
1661 
1662 	/* Ext4 fast commit stuff */
1663 	atomic_t s_fc_subtid;
1664 	atomic_t s_fc_ineligible_updates;
1665 	/*
1666 	 * After commit starts, the main queue gets locked, and the further
1667 	 * updates get added in the staging queue.
1668 	 */
1669 #define FC_Q_MAIN	0
1670 #define FC_Q_STAGING	1
1671 	struct list_head s_fc_q[2];	/* Inodes staged for fast commit
1672 					 * that have data changes in them.
1673 					 */
1674 	struct list_head s_fc_dentry_q[2];	/* directory entry updates */
1675 	unsigned int s_fc_bytes;
1676 	/*
1677 	 * Main fast commit lock. This lock protects accesses to the
1678 	 * following fields:
1679 	 * ei->i_fc_list, s_fc_dentry_q, s_fc_q, s_fc_bytes, s_fc_bh.
1680 	 */
1681 	spinlock_t s_fc_lock;
1682 	struct buffer_head *s_fc_bh;
1683 	struct ext4_fc_stats s_fc_stats;
1684 	u64 s_fc_avg_commit_time;
1685 #ifdef CONFIG_EXT4_DEBUG
1686 	int s_fc_debug_max_replay;
1687 #endif
1688 	struct ext4_fc_replay_state s_fc_replay_state;
1689 };
1690 
1691 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1692 {
1693 	return sb->s_fs_info;
1694 }
1695 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1696 {
1697 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1698 }
1699 
1700 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1701 {
1702 	return ino == EXT4_ROOT_INO ||
1703 		(ino >= EXT4_FIRST_INO(sb) &&
1704 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1705 }
1706 
1707 /*
1708  * Returns: sbi->field[index]
1709  * Used to access an array element from the following sbi fields which require
1710  * rcu protection to avoid dereferencing an invalid pointer due to reassignment
1711  * - s_group_desc
1712  * - s_group_info
1713  * - s_flex_group
1714  */
1715 #define sbi_array_rcu_deref(sbi, field, index)				   \
1716 ({									   \
1717 	typeof(*((sbi)->field)) _v;					   \
1718 	rcu_read_lock();						   \
1719 	_v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index];	   \
1720 	rcu_read_unlock();						   \
1721 	_v;								   \
1722 })
1723 
1724 /*
1725  * run-time mount flags
1726  */
1727 enum {
1728 	EXT4_MF_MNTDIR_SAMPLED,
1729 	EXT4_MF_FS_ABORTED,	/* Fatal error detected */
1730 	EXT4_MF_FC_INELIGIBLE,	/* Fast commit ineligible */
1731 	EXT4_MF_FC_COMMITTING	/* File system underoing a fast
1732 				 * commit.
1733 				 */
1734 };
1735 
1736 static inline void ext4_set_mount_flag(struct super_block *sb, int bit)
1737 {
1738 	set_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1739 }
1740 
1741 static inline void ext4_clear_mount_flag(struct super_block *sb, int bit)
1742 {
1743 	clear_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1744 }
1745 
1746 static inline int ext4_test_mount_flag(struct super_block *sb, int bit)
1747 {
1748 	return test_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1749 }
1750 
1751 
1752 /*
1753  * Simulate_fail codes
1754  */
1755 #define EXT4_SIM_BBITMAP_EIO	1
1756 #define EXT4_SIM_BBITMAP_CRC	2
1757 #define EXT4_SIM_IBITMAP_EIO	3
1758 #define EXT4_SIM_IBITMAP_CRC	4
1759 #define EXT4_SIM_INODE_EIO	5
1760 #define EXT4_SIM_INODE_CRC	6
1761 #define EXT4_SIM_DIRBLOCK_EIO	7
1762 #define EXT4_SIM_DIRBLOCK_CRC	8
1763 
1764 static inline bool ext4_simulate_fail(struct super_block *sb,
1765 				     unsigned long code)
1766 {
1767 #ifdef CONFIG_EXT4_DEBUG
1768 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1769 
1770 	if (unlikely(sbi->s_simulate_fail == code)) {
1771 		sbi->s_simulate_fail = 0;
1772 		return true;
1773 	}
1774 #endif
1775 	return false;
1776 }
1777 
1778 static inline void ext4_simulate_fail_bh(struct super_block *sb,
1779 					 struct buffer_head *bh,
1780 					 unsigned long code)
1781 {
1782 	if (!IS_ERR(bh) && ext4_simulate_fail(sb, code))
1783 		clear_buffer_uptodate(bh);
1784 }
1785 
1786 /*
1787  * Error number codes for s_{first,last}_error_errno
1788  *
1789  * Linux errno numbers are architecture specific, so we need to translate
1790  * them into something which is architecture independent.   We don't define
1791  * codes for all errno's; just the ones which are most likely to be the cause
1792  * of an ext4_error() call.
1793  */
1794 #define EXT4_ERR_UNKNOWN	 1
1795 #define EXT4_ERR_EIO		 2
1796 #define EXT4_ERR_ENOMEM		 3
1797 #define EXT4_ERR_EFSBADCRC	 4
1798 #define EXT4_ERR_EFSCORRUPTED	 5
1799 #define EXT4_ERR_ENOSPC		 6
1800 #define EXT4_ERR_ENOKEY		 7
1801 #define EXT4_ERR_EROFS		 8
1802 #define EXT4_ERR_EFBIG		 9
1803 #define EXT4_ERR_EEXIST		10
1804 #define EXT4_ERR_ERANGE		11
1805 #define EXT4_ERR_EOVERFLOW	12
1806 #define EXT4_ERR_EBUSY		13
1807 #define EXT4_ERR_ENOTDIR	14
1808 #define EXT4_ERR_ENOTEMPTY	15
1809 #define EXT4_ERR_ESHUTDOWN	16
1810 #define EXT4_ERR_EFAULT		17
1811 
1812 /*
1813  * Inode dynamic state flags
1814  */
1815 enum {
1816 	EXT4_STATE_JDATA,		/* journaled data exists */
1817 	EXT4_STATE_NEW,			/* inode is newly created */
1818 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1819 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1820 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1821 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1822 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1823 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1824 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1825 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1826 	EXT4_STATE_VERITY_IN_PROGRESS,	/* building fs-verity Merkle tree */
1827 	EXT4_STATE_FC_COMMITTING,	/* Fast commit ongoing */
1828 };
1829 
1830 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1831 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1832 {									\
1833 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1834 }									\
1835 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1836 {									\
1837 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1838 }									\
1839 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1840 {									\
1841 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1842 }
1843 
1844 /* Add these declarations here only so that these functions can be
1845  * found by name.  Otherwise, they are very hard to locate. */
1846 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1847 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1848 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1849 EXT4_INODE_BIT_FNS(flag, flags, 0)
1850 
1851 /* Add these declarations here only so that these functions can be
1852  * found by name.  Otherwise, they are very hard to locate. */
1853 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1854 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1855 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1856 #if (BITS_PER_LONG < 64)
1857 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1858 
1859 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1860 {
1861 	(ei)->i_state_flags = 0;
1862 }
1863 #else
1864 EXT4_INODE_BIT_FNS(state, flags, 32)
1865 
1866 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1867 {
1868 	/* We depend on the fact that callers will set i_flags */
1869 }
1870 #endif
1871 #else
1872 /* Assume that user mode programs are passing in an ext4fs superblock, not
1873  * a kernel struct super_block.  This will allow us to call the feature-test
1874  * macros from user land. */
1875 #define EXT4_SB(sb)	(sb)
1876 #endif
1877 
1878 static inline bool ext4_verity_in_progress(struct inode *inode)
1879 {
1880 	return IS_ENABLED(CONFIG_FS_VERITY) &&
1881 	       ext4_test_inode_state(inode, EXT4_STATE_VERITY_IN_PROGRESS);
1882 }
1883 
1884 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1885 
1886 /*
1887  * Codes for operating systems
1888  */
1889 #define EXT4_OS_LINUX		0
1890 #define EXT4_OS_HURD		1
1891 #define EXT4_OS_MASIX		2
1892 #define EXT4_OS_FREEBSD		3
1893 #define EXT4_OS_LITES		4
1894 
1895 /*
1896  * Revision levels
1897  */
1898 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1899 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1900 
1901 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1902 
1903 #define EXT4_GOOD_OLD_INODE_SIZE 128
1904 
1905 #define EXT4_EXTRA_TIMESTAMP_MAX	(((s64)1 << 34) - 1  + S32_MIN)
1906 #define EXT4_NON_EXTRA_TIMESTAMP_MAX	S32_MAX
1907 #define EXT4_TIMESTAMP_MIN		S32_MIN
1908 
1909 /*
1910  * Feature set definitions
1911  */
1912 
1913 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1914 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1915 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1916 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1917 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1918 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1919 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1920 /*
1921  * The reason why "FAST_COMMIT" is a compat feature is that, FS becomes
1922  * incompatible only if fast commit blocks are present in the FS. Since we
1923  * clear the journal (and thus the fast commit blocks), we don't mark FS as
1924  * incompatible. We also have a JBD2 incompat feature, which gets set when
1925  * there are fast commit blocks present in the journal.
1926  */
1927 #define EXT4_FEATURE_COMPAT_FAST_COMMIT		0x0400
1928 #define EXT4_FEATURE_COMPAT_STABLE_INODES	0x0800
1929 
1930 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1931 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1932 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1933 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1934 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1935 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1936 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1937 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1938 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1939 /*
1940  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1941  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1942  * all other data structures' checksums.  However, the METADATA_CSUM and
1943  * GDT_CSUM bits are mutually exclusive.
1944  */
1945 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1946 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1947 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1948 #define EXT4_FEATURE_RO_COMPAT_VERITY		0x8000
1949 
1950 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1951 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1952 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1953 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1954 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1955 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1956 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1957 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1958 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1959 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1960 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1961 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1962 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1963 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1964 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1965 #define EXT4_FEATURE_INCOMPAT_CASEFOLD		0x20000
1966 
1967 extern void ext4_update_dynamic_rev(struct super_block *sb);
1968 
1969 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1970 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1971 { \
1972 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1973 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1974 } \
1975 static inline void ext4_set_feature_##name(struct super_block *sb) \
1976 { \
1977 	ext4_update_dynamic_rev(sb); \
1978 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1979 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1980 } \
1981 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1982 { \
1983 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1984 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1985 }
1986 
1987 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1988 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1989 { \
1990 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1991 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1992 } \
1993 static inline void ext4_set_feature_##name(struct super_block *sb) \
1994 { \
1995 	ext4_update_dynamic_rev(sb); \
1996 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1997 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1998 } \
1999 static inline void ext4_clear_feature_##name(struct super_block *sb) \
2000 { \
2001 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
2002 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
2003 }
2004 
2005 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
2006 static inline bool ext4_has_feature_##name(struct super_block *sb) \
2007 { \
2008 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2009 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
2010 } \
2011 static inline void ext4_set_feature_##name(struct super_block *sb) \
2012 { \
2013 	ext4_update_dynamic_rev(sb); \
2014 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
2015 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2016 } \
2017 static inline void ext4_clear_feature_##name(struct super_block *sb) \
2018 { \
2019 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
2020 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2021 }
2022 
2023 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
2024 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
2025 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
2026 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
2027 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
2028 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
2029 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
2030 EXT4_FEATURE_COMPAT_FUNCS(fast_commit,		FAST_COMMIT)
2031 EXT4_FEATURE_COMPAT_FUNCS(stable_inodes,	STABLE_INODES)
2032 
2033 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
2034 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
2035 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
2036 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
2037 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
2038 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
2039 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
2040 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
2041 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
2042 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
2043 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
2044 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
2045 EXT4_FEATURE_RO_COMPAT_FUNCS(verity,		VERITY)
2046 
2047 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
2048 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
2049 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
2050 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
2051 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
2052 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
2053 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
2054 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
2055 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
2056 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
2057 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
2058 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
2059 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
2060 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
2061 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
2062 EXT4_FEATURE_INCOMPAT_FUNCS(casefold,		CASEFOLD)
2063 
2064 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2065 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2066 					 EXT4_FEATURE_INCOMPAT_META_BG)
2067 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2068 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2069 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2070 
2071 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2072 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2073 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
2074 					 EXT4_FEATURE_INCOMPAT_META_BG)
2075 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2076 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2077 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2078 
2079 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2080 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2081 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
2082 					 EXT4_FEATURE_INCOMPAT_META_BG| \
2083 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
2084 					 EXT4_FEATURE_INCOMPAT_64BIT| \
2085 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
2086 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
2087 					 EXT4_FEATURE_INCOMPAT_MMP | \
2088 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
2089 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
2090 					 EXT4_FEATURE_INCOMPAT_CASEFOLD | \
2091 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
2092 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
2093 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2094 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2095 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
2096 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
2097 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
2098 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
2099 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
2100 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
2101 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
2102 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
2103 					 EXT4_FEATURE_RO_COMPAT_PROJECT |\
2104 					 EXT4_FEATURE_RO_COMPAT_VERITY)
2105 
2106 #define EXTN_FEATURE_FUNCS(ver) \
2107 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
2108 { \
2109 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
2110 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
2111 } \
2112 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
2113 { \
2114 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2115 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
2116 } \
2117 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
2118 { \
2119 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2120 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
2121 }
2122 
2123 EXTN_FEATURE_FUNCS(2)
2124 EXTN_FEATURE_FUNCS(3)
2125 EXTN_FEATURE_FUNCS(4)
2126 
2127 static inline bool ext4_has_compat_features(struct super_block *sb)
2128 {
2129 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
2130 }
2131 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
2132 {
2133 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
2134 }
2135 static inline bool ext4_has_incompat_features(struct super_block *sb)
2136 {
2137 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
2138 }
2139 
2140 /*
2141  * Superblock flags
2142  */
2143 #define EXT4_FLAGS_RESIZING	0
2144 #define EXT4_FLAGS_SHUTDOWN	1
2145 #define EXT4_FLAGS_BDEV_IS_DAX	2
2146 
2147 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
2148 {
2149 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
2150 }
2151 
2152 
2153 /*
2154  * Default values for user and/or group using reserved blocks
2155  */
2156 #define	EXT4_DEF_RESUID		0
2157 #define	EXT4_DEF_RESGID		0
2158 
2159 /*
2160  * Default project ID
2161  */
2162 #define	EXT4_DEF_PROJID		0
2163 
2164 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
2165 
2166 /*
2167  * Default mount options
2168  */
2169 #define EXT4_DEFM_DEBUG		0x0001
2170 #define EXT4_DEFM_BSDGROUPS	0x0002
2171 #define EXT4_DEFM_XATTR_USER	0x0004
2172 #define EXT4_DEFM_ACL		0x0008
2173 #define EXT4_DEFM_UID16		0x0010
2174 #define EXT4_DEFM_JMODE		0x0060
2175 #define EXT4_DEFM_JMODE_DATA	0x0020
2176 #define EXT4_DEFM_JMODE_ORDERED	0x0040
2177 #define EXT4_DEFM_JMODE_WBACK	0x0060
2178 #define EXT4_DEFM_NOBARRIER	0x0100
2179 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
2180 #define EXT4_DEFM_DISCARD	0x0400
2181 #define EXT4_DEFM_NODELALLOC	0x0800
2182 
2183 /*
2184  * Default journal batch times
2185  */
2186 #define EXT4_DEF_MIN_BATCH_TIME	0
2187 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
2188 
2189 /*
2190  * Minimum number of groups in a flexgroup before we separate out
2191  * directories into the first block group of a flexgroup
2192  */
2193 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
2194 
2195 /*
2196  * Structure of a directory entry
2197  */
2198 #define EXT4_NAME_LEN 255
2199 
2200 struct ext4_dir_entry {
2201 	__le32	inode;			/* Inode number */
2202 	__le16	rec_len;		/* Directory entry length */
2203 	__le16	name_len;		/* Name length */
2204 	char	name[EXT4_NAME_LEN];	/* File name */
2205 };
2206 
2207 
2208 /*
2209  * Encrypted Casefolded entries require saving the hash on disk. This structure
2210  * followed ext4_dir_entry_2's name[name_len] at the next 4 byte aligned
2211  * boundary.
2212  */
2213 struct ext4_dir_entry_hash {
2214 	__le32 hash;
2215 	__le32 minor_hash;
2216 };
2217 
2218 /*
2219  * The new version of the directory entry.  Since EXT4 structures are
2220  * stored in intel byte order, and the name_len field could never be
2221  * bigger than 255 chars, it's safe to reclaim the extra byte for the
2222  * file_type field.
2223  */
2224 struct ext4_dir_entry_2 {
2225 	__le32	inode;			/* Inode number */
2226 	__le16	rec_len;		/* Directory entry length */
2227 	__u8	name_len;		/* Name length */
2228 	__u8	file_type;		/* See file type macros EXT4_FT_* below */
2229 	char	name[EXT4_NAME_LEN];	/* File name */
2230 };
2231 
2232 /*
2233  * Access the hashes at the end of ext4_dir_entry_2
2234  */
2235 #define EXT4_DIRENT_HASHES(entry) \
2236 	((struct ext4_dir_entry_hash *) \
2237 		(((void *)(entry)) + \
2238 		((8 + (entry)->name_len + EXT4_DIR_ROUND) & ~EXT4_DIR_ROUND)))
2239 #define EXT4_DIRENT_HASH(entry) le32_to_cpu(EXT4_DIRENT_HASHES(de)->hash)
2240 #define EXT4_DIRENT_MINOR_HASH(entry) \
2241 		le32_to_cpu(EXT4_DIRENT_HASHES(de)->minor_hash)
2242 
2243 static inline bool ext4_hash_in_dirent(const struct inode *inode)
2244 {
2245 	return IS_CASEFOLDED(inode) && IS_ENCRYPTED(inode);
2246 }
2247 
2248 /*
2249  * This is a bogus directory entry at the end of each leaf block that
2250  * records checksums.
2251  */
2252 struct ext4_dir_entry_tail {
2253 	__le32	det_reserved_zero1;	/* Pretend to be unused */
2254 	__le16	det_rec_len;		/* 12 */
2255 	__u8	det_reserved_zero2;	/* Zero name length */
2256 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
2257 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
2258 };
2259 
2260 #define EXT4_DIRENT_TAIL(block, blocksize) \
2261 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
2262 					((blocksize) - \
2263 					 sizeof(struct ext4_dir_entry_tail))))
2264 
2265 /*
2266  * Ext4 directory file types.  Only the low 3 bits are used.  The
2267  * other bits are reserved for now.
2268  */
2269 #define EXT4_FT_UNKNOWN		0
2270 #define EXT4_FT_REG_FILE	1
2271 #define EXT4_FT_DIR		2
2272 #define EXT4_FT_CHRDEV		3
2273 #define EXT4_FT_BLKDEV		4
2274 #define EXT4_FT_FIFO		5
2275 #define EXT4_FT_SOCK		6
2276 #define EXT4_FT_SYMLINK		7
2277 
2278 #define EXT4_FT_MAX		8
2279 
2280 #define EXT4_FT_DIR_CSUM	0xDE
2281 
2282 /*
2283  * EXT4_DIR_PAD defines the directory entries boundaries
2284  *
2285  * NOTE: It must be a multiple of 4
2286  */
2287 #define EXT4_DIR_PAD			4
2288 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
2289 #define EXT4_MAX_REC_LEN		((1<<16)-1)
2290 
2291 /*
2292  * The rec_len is dependent on the type of directory. Directories that are
2293  * casefolded and encrypted need to store the hash as well, so we add room for
2294  * ext4_extended_dir_entry_2. For all entries related to '.' or '..' you should
2295  * pass NULL for dir, as those entries do not use the extra fields.
2296  */
2297 static inline unsigned int ext4_dir_rec_len(__u8 name_len,
2298 						const struct inode *dir)
2299 {
2300 	int rec_len = (name_len + 8 + EXT4_DIR_ROUND);
2301 
2302 	if (dir && ext4_hash_in_dirent(dir))
2303 		rec_len += sizeof(struct ext4_dir_entry_hash);
2304 	return (rec_len & ~EXT4_DIR_ROUND);
2305 }
2306 
2307 /*
2308  * If we ever get support for fs block sizes > page_size, we'll need
2309  * to remove the #if statements in the next two functions...
2310  */
2311 static inline unsigned int
2312 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
2313 {
2314 	unsigned len = le16_to_cpu(dlen);
2315 
2316 #if (PAGE_SIZE >= 65536)
2317 	if (len == EXT4_MAX_REC_LEN || len == 0)
2318 		return blocksize;
2319 	return (len & 65532) | ((len & 3) << 16);
2320 #else
2321 	return len;
2322 #endif
2323 }
2324 
2325 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2326 {
2327 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
2328 		BUG();
2329 #if (PAGE_SIZE >= 65536)
2330 	if (len < 65536)
2331 		return cpu_to_le16(len);
2332 	if (len == blocksize) {
2333 		if (blocksize == 65536)
2334 			return cpu_to_le16(EXT4_MAX_REC_LEN);
2335 		else
2336 			return cpu_to_le16(0);
2337 	}
2338 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2339 #else
2340 	return cpu_to_le16(len);
2341 #endif
2342 }
2343 
2344 /*
2345  * Hash Tree Directory indexing
2346  * (c) Daniel Phillips, 2001
2347  */
2348 
2349 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2350 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2351 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2352 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2353 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2354 
2355 /* Legal values for the dx_root hash_version field: */
2356 
2357 #define DX_HASH_LEGACY			0
2358 #define DX_HASH_HALF_MD4		1
2359 #define DX_HASH_TEA			2
2360 #define DX_HASH_LEGACY_UNSIGNED		3
2361 #define DX_HASH_HALF_MD4_UNSIGNED	4
2362 #define DX_HASH_TEA_UNSIGNED		5
2363 #define DX_HASH_SIPHASH			6
2364 
2365 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2366 			      const void *address, unsigned int length)
2367 {
2368 	struct {
2369 		struct shash_desc shash;
2370 		char ctx[4];
2371 	} desc;
2372 
2373 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2374 
2375 	desc.shash.tfm = sbi->s_chksum_driver;
2376 	*(u32 *)desc.ctx = crc;
2377 
2378 	BUG_ON(crypto_shash_update(&desc.shash, address, length));
2379 
2380 	return *(u32 *)desc.ctx;
2381 }
2382 
2383 #ifdef __KERNEL__
2384 
2385 /* hash info structure used by the directory hash */
2386 struct dx_hash_info
2387 {
2388 	u32		hash;
2389 	u32		minor_hash;
2390 	int		hash_version;
2391 	u32		*seed;
2392 };
2393 
2394 
2395 /* 32 and 64 bit signed EOF for dx directories */
2396 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2397 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2398 
2399 
2400 /*
2401  * Control parameters used by ext4_htree_next_block
2402  */
2403 #define HASH_NB_ALWAYS		1
2404 
2405 struct ext4_filename {
2406 	const struct qstr *usr_fname;
2407 	struct fscrypt_str disk_name;
2408 	struct dx_hash_info hinfo;
2409 #ifdef CONFIG_FS_ENCRYPTION
2410 	struct fscrypt_str crypto_buf;
2411 #endif
2412 #ifdef CONFIG_UNICODE
2413 	struct fscrypt_str cf_name;
2414 #endif
2415 };
2416 
2417 #define fname_name(p) ((p)->disk_name.name)
2418 #define fname_usr_name(p) ((p)->usr_fname->name)
2419 #define fname_len(p)  ((p)->disk_name.len)
2420 
2421 /*
2422  * Describe an inode's exact location on disk and in memory
2423  */
2424 struct ext4_iloc
2425 {
2426 	struct buffer_head *bh;
2427 	unsigned long offset;
2428 	ext4_group_t block_group;
2429 };
2430 
2431 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2432 {
2433 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2434 }
2435 
2436 static inline bool ext4_is_quota_file(struct inode *inode)
2437 {
2438 	return IS_NOQUOTA(inode) &&
2439 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2440 }
2441 
2442 /*
2443  * This structure is stuffed into the struct file's private_data field
2444  * for directories.  It is where we put information so that we can do
2445  * readdir operations in hash tree order.
2446  */
2447 struct dir_private_info {
2448 	struct rb_root	root;
2449 	struct rb_node	*curr_node;
2450 	struct fname	*extra_fname;
2451 	loff_t		last_pos;
2452 	__u32		curr_hash;
2453 	__u32		curr_minor_hash;
2454 	__u32		next_hash;
2455 };
2456 
2457 /* calculate the first block number of the group */
2458 static inline ext4_fsblk_t
2459 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2460 {
2461 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2462 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2463 }
2464 
2465 /*
2466  * Special error return code only used by dx_probe() and its callers.
2467  */
2468 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2469 
2470 /* htree levels for ext4 */
2471 #define	EXT4_HTREE_LEVEL_COMPAT	2
2472 #define	EXT4_HTREE_LEVEL	3
2473 
2474 static inline int ext4_dir_htree_level(struct super_block *sb)
2475 {
2476 	return ext4_has_feature_largedir(sb) ?
2477 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2478 }
2479 
2480 /*
2481  * Timeout and state flag for lazy initialization inode thread.
2482  */
2483 #define EXT4_DEF_LI_WAIT_MULT			10
2484 #define EXT4_DEF_LI_MAX_START_DELAY		5
2485 #define EXT4_LAZYINIT_QUIT			0x0001
2486 #define EXT4_LAZYINIT_RUNNING			0x0002
2487 
2488 /*
2489  * Lazy inode table initialization info
2490  */
2491 struct ext4_lazy_init {
2492 	unsigned long		li_state;
2493 	struct list_head	li_request_list;
2494 	struct mutex		li_list_mtx;
2495 };
2496 
2497 enum ext4_li_mode {
2498 	EXT4_LI_MODE_PREFETCH_BBITMAP,
2499 	EXT4_LI_MODE_ITABLE,
2500 };
2501 
2502 struct ext4_li_request {
2503 	struct super_block	*lr_super;
2504 	enum ext4_li_mode	lr_mode;
2505 	ext4_group_t		lr_first_not_zeroed;
2506 	ext4_group_t		lr_next_group;
2507 	struct list_head	lr_request;
2508 	unsigned long		lr_next_sched;
2509 	unsigned long		lr_timeout;
2510 };
2511 
2512 struct ext4_features {
2513 	struct kobject f_kobj;
2514 	struct completion f_kobj_unregister;
2515 };
2516 
2517 /*
2518  * This structure will be used for multiple mount protection. It will be
2519  * written into the block number saved in the s_mmp_block field in the
2520  * superblock. Programs that check MMP should assume that if
2521  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2522  * to use the filesystem, regardless of how old the timestamp is.
2523  */
2524 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2525 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2526 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2527 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2528 
2529 struct mmp_struct {
2530 	__le32	mmp_magic;		/* Magic number for MMP */
2531 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2532 
2533 	/*
2534 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2535 	 * purposes and do not affect the correctness of the algorithm
2536 	 */
2537 	__le64	mmp_time;		/* Time last updated */
2538 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2539 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2540 
2541 	/*
2542 	 * mmp_check_interval is used to verify if the MMP block has been
2543 	 * updated on the block device. The value is updated based on the
2544 	 * maximum time to write the MMP block during an update cycle.
2545 	 */
2546 	__le16	mmp_check_interval;
2547 
2548 	__le16	mmp_pad1;
2549 	__le32	mmp_pad2[226];
2550 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2551 };
2552 
2553 /* arguments passed to the mmp thread */
2554 struct mmpd_data {
2555 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2556 	struct super_block *sb;  /* super block of the fs */
2557 };
2558 
2559 /*
2560  * Check interval multiplier
2561  * The MMP block is written every update interval and initially checked every
2562  * update interval x the multiplier (the value is then adapted based on the
2563  * write latency). The reason is that writes can be delayed under load and we
2564  * don't want readers to incorrectly assume that the filesystem is no longer
2565  * in use.
2566  */
2567 #define EXT4_MMP_CHECK_MULT		2UL
2568 
2569 /*
2570  * Minimum interval for MMP checking in seconds.
2571  */
2572 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2573 
2574 /*
2575  * Maximum interval for MMP checking in seconds.
2576  */
2577 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2578 
2579 /*
2580  * Function prototypes
2581  */
2582 
2583 /*
2584  * Ok, these declarations are also in <linux/kernel.h> but none of the
2585  * ext4 source programs needs to include it so they are duplicated here.
2586  */
2587 # define NORET_TYPE	/**/
2588 # define ATTRIB_NORET	__attribute__((noreturn))
2589 # define NORET_AND	noreturn,
2590 
2591 /* bitmap.c */
2592 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2593 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2594 				struct ext4_group_desc *gdp,
2595 				struct buffer_head *bh, int sz);
2596 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2597 				  struct ext4_group_desc *gdp,
2598 				  struct buffer_head *bh, int sz);
2599 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2600 				struct ext4_group_desc *gdp,
2601 				struct buffer_head *bh);
2602 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2603 				  struct ext4_group_desc *gdp,
2604 				  struct buffer_head *bh);
2605 
2606 /* balloc.c */
2607 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2608 					 ext4_fsblk_t blocknr,
2609 					 ext4_group_t *blockgrpp,
2610 					 ext4_grpblk_t *offsetp);
2611 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2612 					  ext4_fsblk_t block);
2613 
2614 extern unsigned int ext4_block_group(struct super_block *sb,
2615 			ext4_fsblk_t blocknr);
2616 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2617 			ext4_fsblk_t blocknr);
2618 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2619 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2620 			ext4_group_t group);
2621 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2622 					 ext4_fsblk_t goal,
2623 					 unsigned int flags,
2624 					 unsigned long *count,
2625 					 int *errp);
2626 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2627 				    s64 nclusters, unsigned int flags);
2628 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2629 extern void ext4_check_blocks_bitmap(struct super_block *);
2630 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2631 						    ext4_group_t block_group,
2632 						    struct buffer_head ** bh);
2633 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2634 
2635 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2636 						ext4_group_t block_group,
2637 						bool ignore_locked);
2638 extern int ext4_wait_block_bitmap(struct super_block *sb,
2639 				  ext4_group_t block_group,
2640 				  struct buffer_head *bh);
2641 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2642 						  ext4_group_t block_group);
2643 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2644 					      ext4_group_t block_group,
2645 					      struct ext4_group_desc *gdp);
2646 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2647 
2648 #ifdef CONFIG_UNICODE
2649 extern int ext4_fname_setup_ci_filename(struct inode *dir,
2650 					 const struct qstr *iname,
2651 					 struct ext4_filename *fname);
2652 #endif
2653 
2654 #ifdef CONFIG_FS_ENCRYPTION
2655 static inline void ext4_fname_from_fscrypt_name(struct ext4_filename *dst,
2656 						const struct fscrypt_name *src)
2657 {
2658 	memset(dst, 0, sizeof(*dst));
2659 
2660 	dst->usr_fname = src->usr_fname;
2661 	dst->disk_name = src->disk_name;
2662 	dst->hinfo.hash = src->hash;
2663 	dst->hinfo.minor_hash = src->minor_hash;
2664 	dst->crypto_buf = src->crypto_buf;
2665 }
2666 
2667 static inline int ext4_fname_setup_filename(struct inode *dir,
2668 					    const struct qstr *iname,
2669 					    int lookup,
2670 					    struct ext4_filename *fname)
2671 {
2672 	struct fscrypt_name name;
2673 	int err;
2674 
2675 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2676 	if (err)
2677 		return err;
2678 
2679 	ext4_fname_from_fscrypt_name(fname, &name);
2680 
2681 #ifdef CONFIG_UNICODE
2682 	err = ext4_fname_setup_ci_filename(dir, iname, fname);
2683 #endif
2684 	return err;
2685 }
2686 
2687 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2688 					    struct dentry *dentry,
2689 					    struct ext4_filename *fname)
2690 {
2691 	struct fscrypt_name name;
2692 	int err;
2693 
2694 	err = fscrypt_prepare_lookup(dir, dentry, &name);
2695 	if (err)
2696 		return err;
2697 
2698 	ext4_fname_from_fscrypt_name(fname, &name);
2699 
2700 #ifdef CONFIG_UNICODE
2701 	err = ext4_fname_setup_ci_filename(dir, &dentry->d_name, fname);
2702 #endif
2703 	return err;
2704 }
2705 
2706 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2707 {
2708 	struct fscrypt_name name;
2709 
2710 	name.crypto_buf = fname->crypto_buf;
2711 	fscrypt_free_filename(&name);
2712 
2713 	fname->crypto_buf.name = NULL;
2714 	fname->usr_fname = NULL;
2715 	fname->disk_name.name = NULL;
2716 
2717 #ifdef CONFIG_UNICODE
2718 	kfree(fname->cf_name.name);
2719 	fname->cf_name.name = NULL;
2720 #endif
2721 }
2722 #else /* !CONFIG_FS_ENCRYPTION */
2723 static inline int ext4_fname_setup_filename(struct inode *dir,
2724 					    const struct qstr *iname,
2725 					    int lookup,
2726 					    struct ext4_filename *fname)
2727 {
2728 	int err = 0;
2729 	fname->usr_fname = iname;
2730 	fname->disk_name.name = (unsigned char *) iname->name;
2731 	fname->disk_name.len = iname->len;
2732 
2733 #ifdef CONFIG_UNICODE
2734 	err = ext4_fname_setup_ci_filename(dir, iname, fname);
2735 #endif
2736 
2737 	return err;
2738 }
2739 
2740 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2741 					    struct dentry *dentry,
2742 					    struct ext4_filename *fname)
2743 {
2744 	return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
2745 }
2746 
2747 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2748 {
2749 #ifdef CONFIG_UNICODE
2750 	kfree(fname->cf_name.name);
2751 	fname->cf_name.name = NULL;
2752 #endif
2753 }
2754 #endif /* !CONFIG_FS_ENCRYPTION */
2755 
2756 /* dir.c */
2757 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2758 				  struct file *,
2759 				  struct ext4_dir_entry_2 *,
2760 				  struct buffer_head *, char *, int,
2761 				  unsigned int);
2762 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset) \
2763 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2764 				(de), (bh), (buf), (size), (offset)))
2765 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2766 				__u32 minor_hash,
2767 				struct ext4_dir_entry_2 *dirent,
2768 				struct fscrypt_str *ent_name);
2769 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2770 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2771 			     struct buffer_head *bh,
2772 			     void *buf, int buf_size,
2773 			     struct ext4_filename *fname,
2774 			     struct ext4_dir_entry_2 **dest_de);
2775 void ext4_insert_dentry(struct inode *dir, struct inode *inode,
2776 			struct ext4_dir_entry_2 *de,
2777 			int buf_size,
2778 			struct ext4_filename *fname);
2779 static inline void ext4_update_dx_flag(struct inode *inode)
2780 {
2781 	if (!ext4_has_feature_dir_index(inode->i_sb) &&
2782 	    ext4_test_inode_flag(inode, EXT4_INODE_INDEX)) {
2783 		/* ext4_iget() should have caught this... */
2784 		WARN_ON_ONCE(ext4_has_feature_metadata_csum(inode->i_sb));
2785 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2786 	}
2787 }
2788 static const unsigned char ext4_filetype_table[] = {
2789 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2790 };
2791 
2792 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2793 {
2794 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2795 		return DT_UNKNOWN;
2796 
2797 	return ext4_filetype_table[filetype];
2798 }
2799 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2800 			     void *buf, int buf_size);
2801 
2802 /* fsync.c */
2803 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2804 
2805 /* hash.c */
2806 extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
2807 			  struct dx_hash_info *hinfo);
2808 
2809 /* ialloc.c */
2810 extern int ext4_mark_inode_used(struct super_block *sb, int ino);
2811 extern struct inode *__ext4_new_inode(struct user_namespace *, handle_t *,
2812 				      struct inode *, umode_t,
2813 				      const struct qstr *qstr, __u32 goal,
2814 				      uid_t *owner, __u32 i_flags,
2815 				      int handle_type, unsigned int line_no,
2816 				      int nblocks);
2817 
2818 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags)          \
2819 	__ext4_new_inode(&init_user_ns, (handle), (dir), (mode), (qstr),       \
2820 			 (goal), (owner), i_flags, 0, 0, 0)
2821 #define ext4_new_inode_start_handle(mnt_userns, dir, mode, qstr, goal, owner, \
2822 				    type, nblocks)		    \
2823 	__ext4_new_inode((mnt_userns), NULL, (dir), (mode), (qstr), (goal), (owner), \
2824 			 0, (type), __LINE__, (nblocks))
2825 
2826 
2827 extern void ext4_free_inode(handle_t *, struct inode *);
2828 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2829 extern unsigned long ext4_count_free_inodes(struct super_block *);
2830 extern unsigned long ext4_count_dirs(struct super_block *);
2831 extern void ext4_check_inodes_bitmap(struct super_block *);
2832 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2833 extern int ext4_init_inode_table(struct super_block *sb,
2834 				 ext4_group_t group, int barrier);
2835 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2836 
2837 /* fast_commit.c */
2838 int ext4_fc_info_show(struct seq_file *seq, void *v);
2839 void ext4_fc_init(struct super_block *sb, journal_t *journal);
2840 void ext4_fc_init_inode(struct inode *inode);
2841 void ext4_fc_track_range(handle_t *handle, struct inode *inode, ext4_lblk_t start,
2842 			 ext4_lblk_t end);
2843 void __ext4_fc_track_unlink(handle_t *handle, struct inode *inode,
2844 	struct dentry *dentry);
2845 void __ext4_fc_track_link(handle_t *handle, struct inode *inode,
2846 	struct dentry *dentry);
2847 void ext4_fc_track_unlink(handle_t *handle, struct dentry *dentry);
2848 void ext4_fc_track_link(handle_t *handle, struct dentry *dentry);
2849 void __ext4_fc_track_create(handle_t *handle, struct inode *inode,
2850 			    struct dentry *dentry);
2851 void ext4_fc_track_create(handle_t *handle, struct dentry *dentry);
2852 void ext4_fc_track_inode(handle_t *handle, struct inode *inode);
2853 void ext4_fc_mark_ineligible(struct super_block *sb, int reason);
2854 void ext4_fc_start_ineligible(struct super_block *sb, int reason);
2855 void ext4_fc_stop_ineligible(struct super_block *sb);
2856 void ext4_fc_start_update(struct inode *inode);
2857 void ext4_fc_stop_update(struct inode *inode);
2858 void ext4_fc_del(struct inode *inode);
2859 bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block);
2860 void ext4_fc_replay_cleanup(struct super_block *sb);
2861 int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
2862 int __init ext4_fc_init_dentry_cache(void);
2863 
2864 /* mballoc.c */
2865 extern const struct seq_operations ext4_mb_seq_groups_ops;
2866 extern const struct seq_operations ext4_mb_seq_structs_summary_ops;
2867 extern long ext4_mb_stats;
2868 extern long ext4_mb_max_to_scan;
2869 extern int ext4_seq_mb_stats_show(struct seq_file *seq, void *offset);
2870 extern int ext4_mb_init(struct super_block *);
2871 extern int ext4_mb_release(struct super_block *);
2872 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2873 				struct ext4_allocation_request *, int *);
2874 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2875 extern void ext4_discard_preallocations(struct inode *, unsigned int);
2876 extern int __init ext4_init_mballoc(void);
2877 extern void ext4_exit_mballoc(void);
2878 extern ext4_group_t ext4_mb_prefetch(struct super_block *sb,
2879 				     ext4_group_t group,
2880 				     unsigned int nr, int *cnt);
2881 extern void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group,
2882 				  unsigned int nr);
2883 
2884 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2885 			     struct buffer_head *bh, ext4_fsblk_t block,
2886 			     unsigned long count, int flags);
2887 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2888 				   ext4_group_t ngroups);
2889 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2890 		ext4_group_t i, struct ext4_group_desc *desc);
2891 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2892 				ext4_fsblk_t block, unsigned long count);
2893 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2894 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2895 extern void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block,
2896 		       int len, int state);
2897 
2898 /* inode.c */
2899 void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
2900 			 struct ext4_inode_info *ei);
2901 int ext4_inode_is_fast_symlink(struct inode *inode);
2902 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2903 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2904 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2905 		     bool wait, struct buffer_head **bhs);
2906 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2907 			     struct buffer_head *bh_result, int create);
2908 int ext4_get_block(struct inode *inode, sector_t iblock,
2909 		   struct buffer_head *bh_result, int create);
2910 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2911 			   struct buffer_head *bh, int create);
2912 int ext4_walk_page_buffers(handle_t *handle,
2913 			   struct buffer_head *head,
2914 			   unsigned from,
2915 			   unsigned to,
2916 			   int *partial,
2917 			   int (*fn)(handle_t *handle,
2918 				     struct buffer_head *bh));
2919 int do_journal_get_write_access(handle_t *handle,
2920 				struct buffer_head *bh);
2921 #define FALL_BACK_TO_NONDELALLOC 1
2922 #define CONVERT_INLINE_DATA	 2
2923 
2924 typedef enum {
2925 	EXT4_IGET_NORMAL =	0,
2926 	EXT4_IGET_SPECIAL =	0x0001, /* OK to iget a system inode */
2927 	EXT4_IGET_HANDLE = 	0x0002	/* Inode # is from a handle */
2928 } ext4_iget_flags;
2929 
2930 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2931 				 ext4_iget_flags flags, const char *function,
2932 				 unsigned int line);
2933 
2934 #define ext4_iget(sb, ino, flags) \
2935 	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2936 
2937 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2938 extern int  ext4_setattr(struct user_namespace *, struct dentry *,
2939 			 struct iattr *);
2940 extern int  ext4_getattr(struct user_namespace *, const struct path *,
2941 			 struct kstat *, u32, unsigned int);
2942 extern void ext4_evict_inode(struct inode *);
2943 extern void ext4_clear_inode(struct inode *);
2944 extern int  ext4_file_getattr(struct user_namespace *, const struct path *,
2945 			      struct kstat *, u32, unsigned int);
2946 extern int  ext4_sync_inode(handle_t *, struct inode *);
2947 extern void ext4_dirty_inode(struct inode *, int);
2948 extern int ext4_change_inode_journal_flag(struct inode *, int);
2949 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2950 extern int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino,
2951 			  struct ext4_iloc *iloc);
2952 extern int ext4_inode_attach_jinode(struct inode *inode);
2953 extern int ext4_can_truncate(struct inode *inode);
2954 extern int ext4_truncate(struct inode *);
2955 extern int ext4_break_layouts(struct inode *);
2956 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2957 extern void ext4_set_inode_flags(struct inode *, bool init);
2958 extern int ext4_alloc_da_blocks(struct inode *inode);
2959 extern void ext4_set_aops(struct inode *inode);
2960 extern int ext4_writepage_trans_blocks(struct inode *);
2961 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2962 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2963 			     loff_t lstart, loff_t lend);
2964 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
2965 extern vm_fault_t ext4_filemap_fault(struct vm_fault *vmf);
2966 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2967 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2968 extern void ext4_da_release_space(struct inode *inode, int to_free);
2969 extern void ext4_da_update_reserve_space(struct inode *inode,
2970 					int used, int quota_claim);
2971 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2972 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2973 
2974 /* indirect.c */
2975 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2976 				struct ext4_map_blocks *map, int flags);
2977 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2978 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2979 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2980 				 ext4_lblk_t start, ext4_lblk_t end);
2981 
2982 /* ioctl.c */
2983 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2984 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2985 int ext4_fileattr_set(struct user_namespace *mnt_userns,
2986 		      struct dentry *dentry, struct fileattr *fa);
2987 int ext4_fileattr_get(struct dentry *dentry, struct fileattr *fa);
2988 extern void ext4_reset_inode_seed(struct inode *inode);
2989 
2990 /* migrate.c */
2991 extern int ext4_ext_migrate(struct inode *);
2992 extern int ext4_ind_migrate(struct inode *inode);
2993 
2994 /* namei.c */
2995 extern int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2996 			     struct inode *inode);
2997 extern int ext4_dirblock_csum_verify(struct inode *inode,
2998 				     struct buffer_head *bh);
2999 extern int ext4_orphan_add(handle_t *, struct inode *);
3000 extern int ext4_orphan_del(handle_t *, struct inode *);
3001 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
3002 				__u32 start_minor_hash, __u32 *next_hash);
3003 extern int ext4_search_dir(struct buffer_head *bh,
3004 			   char *search_buf,
3005 			   int buf_size,
3006 			   struct inode *dir,
3007 			   struct ext4_filename *fname,
3008 			   unsigned int offset,
3009 			   struct ext4_dir_entry_2 **res_dir);
3010 extern int ext4_generic_delete_entry(struct inode *dir,
3011 				     struct ext4_dir_entry_2 *de_del,
3012 				     struct buffer_head *bh,
3013 				     void *entry_buf,
3014 				     int buf_size,
3015 				     int csum_size);
3016 extern bool ext4_empty_dir(struct inode *inode);
3017 
3018 /* resize.c */
3019 extern void ext4_kvfree_array_rcu(void *to_free);
3020 extern int ext4_group_add(struct super_block *sb,
3021 				struct ext4_new_group_data *input);
3022 extern int ext4_group_extend(struct super_block *sb,
3023 				struct ext4_super_block *es,
3024 				ext4_fsblk_t n_blocks_count);
3025 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
3026 
3027 /* super.c */
3028 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
3029 					 sector_t block, int op_flags);
3030 extern struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
3031 						   sector_t block);
3032 extern void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
3033 				bh_end_io_t *end_io);
3034 extern int ext4_read_bh(struct buffer_head *bh, int op_flags,
3035 			bh_end_io_t *end_io);
3036 extern int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait);
3037 extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
3038 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
3039 extern int ext4_calculate_overhead(struct super_block *sb);
3040 extern void ext4_superblock_csum_set(struct super_block *sb);
3041 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
3042 				    ext4_group_t ngroup);
3043 extern const char *ext4_decode_error(struct super_block *sb, int errno,
3044 				     char nbuf[16]);
3045 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
3046 					     ext4_group_t block_group,
3047 					     unsigned int flags);
3048 
3049 extern __printf(7, 8)
3050 void __ext4_error(struct super_block *, const char *, unsigned int, bool,
3051 		  int, __u64, const char *, ...);
3052 extern __printf(6, 7)
3053 void __ext4_error_inode(struct inode *, const char *, unsigned int,
3054 			ext4_fsblk_t, int, const char *, ...);
3055 extern __printf(5, 6)
3056 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
3057 		     const char *, ...);
3058 extern void __ext4_std_error(struct super_block *, const char *,
3059 			     unsigned int, int);
3060 extern __printf(4, 5)
3061 void __ext4_warning(struct super_block *, const char *, unsigned int,
3062 		    const char *, ...);
3063 extern __printf(4, 5)
3064 void __ext4_warning_inode(const struct inode *inode, const char *function,
3065 			  unsigned int line, const char *fmt, ...);
3066 extern __printf(3, 4)
3067 void __ext4_msg(struct super_block *, const char *, const char *, ...);
3068 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
3069 			   const char *, unsigned int, const char *);
3070 extern __printf(7, 8)
3071 void __ext4_grp_locked_error(const char *, unsigned int,
3072 			     struct super_block *, ext4_group_t,
3073 			     unsigned long, ext4_fsblk_t,
3074 			     const char *, ...);
3075 
3076 #define EXT4_ERROR_INODE(inode, fmt, a...) \
3077 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
3078 
3079 #define EXT4_ERROR_INODE_ERR(inode, err, fmt, a...)			\
3080 	__ext4_error_inode((inode), __func__, __LINE__, 0, (err), (fmt), ## a)
3081 
3082 #define ext4_error_inode_block(inode, block, err, fmt, a...)		\
3083 	__ext4_error_inode((inode), __func__, __LINE__, (block), (err),	\
3084 			   (fmt), ## a)
3085 
3086 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
3087 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
3088 
3089 #define ext4_abort(sb, err, fmt, a...)					\
3090 	__ext4_error((sb), __func__, __LINE__, true, (err), 0, (fmt), ## a)
3091 
3092 #ifdef CONFIG_PRINTK
3093 
3094 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
3095 	__ext4_error_inode(inode, func, line, block, 0, fmt, ##__VA_ARGS__)
3096 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
3097 	__ext4_error_inode((inode), (func), (line), (block), 		\
3098 			   (err), (fmt), ##__VA_ARGS__)
3099 #define ext4_error_file(file, func, line, block, fmt, ...)		\
3100 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
3101 #define ext4_error(sb, fmt, ...)					\
3102 	__ext4_error((sb), __func__, __LINE__, false, 0, 0, (fmt),	\
3103 		##__VA_ARGS__)
3104 #define ext4_error_err(sb, err, fmt, ...)				\
3105 	__ext4_error((sb), __func__, __LINE__, false, (err), 0, (fmt),	\
3106 		##__VA_ARGS__)
3107 #define ext4_warning(sb, fmt, ...)					\
3108 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
3109 #define ext4_warning_inode(inode, fmt, ...)				\
3110 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
3111 #define ext4_msg(sb, level, fmt, ...)				\
3112 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
3113 #define dump_mmp_msg(sb, mmp, msg)					\
3114 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
3115 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
3116 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
3117 				fmt, ##__VA_ARGS__)
3118 
3119 #else
3120 
3121 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
3122 do {									\
3123 	no_printk(fmt, ##__VA_ARGS__);					\
3124 	__ext4_error_inode(inode, "", 0, block, 0, " ");		\
3125 } while (0)
3126 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
3127 do {									\
3128 	no_printk(fmt, ##__VA_ARGS__);					\
3129 	__ext4_error_inode(inode, "", 0, block, err, " ");		\
3130 } while (0)
3131 #define ext4_error_file(file, func, line, block, fmt, ...)		\
3132 do {									\
3133 	no_printk(fmt, ##__VA_ARGS__);					\
3134 	__ext4_error_file(file, "", 0, block, " ");			\
3135 } while (0)
3136 #define ext4_error(sb, fmt, ...)					\
3137 do {									\
3138 	no_printk(fmt, ##__VA_ARGS__);					\
3139 	__ext4_error(sb, "", 0, false, 0, 0, " ");			\
3140 } while (0)
3141 #define ext4_error_err(sb, err, fmt, ...)				\
3142 do {									\
3143 	no_printk(fmt, ##__VA_ARGS__);					\
3144 	__ext4_error(sb, "", 0, false, err, 0, " ");			\
3145 } while (0)
3146 #define ext4_warning(sb, fmt, ...)					\
3147 do {									\
3148 	no_printk(fmt, ##__VA_ARGS__);					\
3149 	__ext4_warning(sb, "", 0, " ");					\
3150 } while (0)
3151 #define ext4_warning_inode(inode, fmt, ...)				\
3152 do {									\
3153 	no_printk(fmt, ##__VA_ARGS__);					\
3154 	__ext4_warning_inode(inode, "", 0, " ");			\
3155 } while (0)
3156 #define ext4_msg(sb, level, fmt, ...)					\
3157 do {									\
3158 	no_printk(fmt, ##__VA_ARGS__);					\
3159 	__ext4_msg(sb, "", " ");					\
3160 } while (0)
3161 #define dump_mmp_msg(sb, mmp, msg)					\
3162 	__dump_mmp_msg(sb, mmp, "", 0, "")
3163 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
3164 do {									\
3165 	no_printk(fmt, ##__VA_ARGS__);				\
3166 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
3167 } while (0)
3168 
3169 #endif
3170 
3171 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
3172 				      struct ext4_group_desc *bg);
3173 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
3174 				      struct ext4_group_desc *bg);
3175 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
3176 				     struct ext4_group_desc *bg);
3177 extern __u32 ext4_free_group_clusters(struct super_block *sb,
3178 				      struct ext4_group_desc *bg);
3179 extern __u32 ext4_free_inodes_count(struct super_block *sb,
3180 				 struct ext4_group_desc *bg);
3181 extern __u32 ext4_used_dirs_count(struct super_block *sb,
3182 				struct ext4_group_desc *bg);
3183 extern __u32 ext4_itable_unused_count(struct super_block *sb,
3184 				   struct ext4_group_desc *bg);
3185 extern void ext4_block_bitmap_set(struct super_block *sb,
3186 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3187 extern void ext4_inode_bitmap_set(struct super_block *sb,
3188 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3189 extern void ext4_inode_table_set(struct super_block *sb,
3190 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
3191 extern void ext4_free_group_clusters_set(struct super_block *sb,
3192 					 struct ext4_group_desc *bg,
3193 					 __u32 count);
3194 extern void ext4_free_inodes_set(struct super_block *sb,
3195 				struct ext4_group_desc *bg, __u32 count);
3196 extern void ext4_used_dirs_set(struct super_block *sb,
3197 				struct ext4_group_desc *bg, __u32 count);
3198 extern void ext4_itable_unused_set(struct super_block *sb,
3199 				   struct ext4_group_desc *bg, __u32 count);
3200 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
3201 				       struct ext4_group_desc *gdp);
3202 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
3203 				     struct ext4_group_desc *gdp);
3204 extern int ext4_register_li_request(struct super_block *sb,
3205 				    ext4_group_t first_not_zeroed);
3206 
3207 static inline int ext4_has_metadata_csum(struct super_block *sb)
3208 {
3209 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
3210 		     !EXT4_SB(sb)->s_chksum_driver);
3211 
3212 	return ext4_has_feature_metadata_csum(sb) &&
3213 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
3214 }
3215 
3216 static inline int ext4_has_group_desc_csum(struct super_block *sb)
3217 {
3218 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
3219 }
3220 
3221 #define ext4_read_incompat_64bit_val(es, name) \
3222 	(((es)->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT) \
3223 		? (ext4_fsblk_t)le32_to_cpu(es->name##_hi) << 32 : 0) | \
3224 		le32_to_cpu(es->name##_lo))
3225 
3226 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
3227 {
3228 	return ext4_read_incompat_64bit_val(es, s_blocks_count);
3229 }
3230 
3231 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
3232 {
3233 	return ext4_read_incompat_64bit_val(es, s_r_blocks_count);
3234 }
3235 
3236 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
3237 {
3238 	return ext4_read_incompat_64bit_val(es, s_free_blocks_count);
3239 }
3240 
3241 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
3242 					 ext4_fsblk_t blk)
3243 {
3244 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
3245 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
3246 }
3247 
3248 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
3249 					      ext4_fsblk_t blk)
3250 {
3251 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
3252 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
3253 }
3254 
3255 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
3256 					   ext4_fsblk_t blk)
3257 {
3258 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
3259 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
3260 }
3261 
3262 static inline loff_t ext4_isize(struct super_block *sb,
3263 				struct ext4_inode *raw_inode)
3264 {
3265 	if (ext4_has_feature_largedir(sb) ||
3266 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
3267 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
3268 			le32_to_cpu(raw_inode->i_size_lo);
3269 
3270 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
3271 }
3272 
3273 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
3274 {
3275 	raw_inode->i_size_lo = cpu_to_le32(i_size);
3276 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
3277 }
3278 
3279 static inline
3280 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
3281 					    ext4_group_t group)
3282 {
3283 	 struct ext4_group_info **grp_info;
3284 	 long indexv, indexh;
3285 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
3286 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
3287 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
3288 	 grp_info = sbi_array_rcu_deref(EXT4_SB(sb), s_group_info, indexv);
3289 	 return grp_info[indexh];
3290 }
3291 
3292 /*
3293  * Reading s_groups_count requires using smp_rmb() afterwards.  See
3294  * the locking protocol documented in the comments of ext4_group_add()
3295  * in resize.c
3296  */
3297 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
3298 {
3299 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
3300 
3301 	smp_rmb();
3302 	return ngroups;
3303 }
3304 
3305 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
3306 					     ext4_group_t block_group)
3307 {
3308 	return block_group >> sbi->s_log_groups_per_flex;
3309 }
3310 
3311 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
3312 {
3313 	return 1 << sbi->s_log_groups_per_flex;
3314 }
3315 
3316 #define ext4_std_error(sb, errno)				\
3317 do {								\
3318 	if ((errno))						\
3319 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
3320 } while (0)
3321 
3322 #ifdef CONFIG_SMP
3323 /* Each CPU can accumulate percpu_counter_batch clusters in their local
3324  * counters. So we need to make sure we have free clusters more
3325  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
3326  */
3327 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
3328 #else
3329 #define EXT4_FREECLUSTERS_WATERMARK 0
3330 #endif
3331 
3332 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
3333 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
3334 {
3335 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
3336 		     !inode_is_locked(inode));
3337 	down_write(&EXT4_I(inode)->i_data_sem);
3338 	if (newsize > EXT4_I(inode)->i_disksize)
3339 		WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
3340 	up_write(&EXT4_I(inode)->i_data_sem);
3341 }
3342 
3343 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
3344 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
3345 {
3346 	int changed = 0;
3347 
3348 	if (newsize > inode->i_size) {
3349 		i_size_write(inode, newsize);
3350 		changed = 1;
3351 	}
3352 	if (newsize > EXT4_I(inode)->i_disksize) {
3353 		ext4_update_i_disksize(inode, newsize);
3354 		changed |= 2;
3355 	}
3356 	return changed;
3357 }
3358 
3359 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
3360 				      loff_t len);
3361 
3362 struct ext4_group_info {
3363 	unsigned long   bb_state;
3364 #ifdef AGGRESSIVE_CHECK
3365 	unsigned long	bb_check_counter;
3366 #endif
3367 	struct rb_root  bb_free_root;
3368 	ext4_grpblk_t	bb_first_free;	/* first free block */
3369 	ext4_grpblk_t	bb_free;	/* total free blocks */
3370 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
3371 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
3372 	ext4_group_t	bb_group;	/* Group number */
3373 	struct          list_head bb_prealloc_list;
3374 #ifdef DOUBLE_CHECK
3375 	void            *bb_bitmap;
3376 #endif
3377 	struct rw_semaphore alloc_sem;
3378 	struct rb_node	bb_avg_fragment_size_rb;
3379 	struct list_head bb_largest_free_order_node;
3380 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
3381 					 * regions, index is order.
3382 					 * bb_counters[3] = 5 means
3383 					 * 5 free 8-block regions. */
3384 };
3385 
3386 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
3387 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
3388 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
3389 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
3390 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT		\
3391 	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
3392 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT		\
3393 	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
3394 #define EXT4_GROUP_INFO_BBITMAP_READ_BIT	4
3395 
3396 #define EXT4_MB_GRP_NEED_INIT(grp)	\
3397 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
3398 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
3399 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3400 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
3401 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3402 
3403 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
3404 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3405 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
3406 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3407 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
3408 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3409 #define EXT4_MB_GRP_TEST_AND_SET_READ(grp)	\
3410 	(test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_READ_BIT, &((grp)->bb_state)))
3411 
3412 #define EXT4_MAX_CONTENTION		8
3413 #define EXT4_CONTENTION_THRESHOLD	2
3414 
3415 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
3416 					      ext4_group_t group)
3417 {
3418 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
3419 }
3420 
3421 /*
3422  * Returns true if the filesystem is busy enough that attempts to
3423  * access the block group locks has run into contention.
3424  */
3425 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
3426 {
3427 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
3428 }
3429 
3430 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
3431 {
3432 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
3433 	if (spin_trylock(lock))
3434 		/*
3435 		 * We're able to grab the lock right away, so drop the
3436 		 * lock contention counter.
3437 		 */
3438 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
3439 	else {
3440 		/*
3441 		 * The lock is busy, so bump the contention counter,
3442 		 * and then wait on the spin lock.
3443 		 */
3444 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
3445 				  EXT4_MAX_CONTENTION);
3446 		spin_lock(lock);
3447 	}
3448 }
3449 
3450 static inline void ext4_unlock_group(struct super_block *sb,
3451 					ext4_group_t group)
3452 {
3453 	spin_unlock(ext4_group_lock_ptr(sb, group));
3454 }
3455 
3456 #ifdef CONFIG_QUOTA
3457 static inline bool ext4_quota_capable(struct super_block *sb)
3458 {
3459 	return (test_opt(sb, QUOTA) || ext4_has_feature_quota(sb));
3460 }
3461 
3462 static inline bool ext4_is_quota_journalled(struct super_block *sb)
3463 {
3464 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3465 
3466 	return (ext4_has_feature_quota(sb) ||
3467 		sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]);
3468 }
3469 #endif
3470 
3471 /*
3472  * Block validity checking
3473  */
3474 #define ext4_check_indirect_blockref(inode, bh)				\
3475 	ext4_check_blockref(__func__, __LINE__, inode,			\
3476 			    (__le32 *)(bh)->b_data,			\
3477 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3478 
3479 #define ext4_ind_check_inode(inode)					\
3480 	ext4_check_blockref(__func__, __LINE__, inode,			\
3481 			    EXT4_I(inode)->i_data,			\
3482 			    EXT4_NDIR_BLOCKS)
3483 
3484 /*
3485  * Inodes and files operations
3486  */
3487 
3488 /* dir.c */
3489 extern const struct file_operations ext4_dir_operations;
3490 
3491 /* file.c */
3492 extern const struct inode_operations ext4_file_inode_operations;
3493 extern const struct file_operations ext4_file_operations;
3494 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
3495 
3496 /* inline.c */
3497 extern int ext4_get_max_inline_size(struct inode *inode);
3498 extern int ext4_find_inline_data_nolock(struct inode *inode);
3499 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
3500 				 unsigned int len);
3501 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3502 
3503 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
3504 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3505 					 struct inode *inode,
3506 					 loff_t pos, unsigned len,
3507 					 unsigned flags,
3508 					 struct page **pagep);
3509 extern int ext4_write_inline_data_end(struct inode *inode,
3510 				      loff_t pos, unsigned len,
3511 				      unsigned copied,
3512 				      struct page *page);
3513 extern struct buffer_head *
3514 ext4_journalled_write_inline_data(struct inode *inode,
3515 				  unsigned len,
3516 				  struct page *page);
3517 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3518 					   struct inode *inode,
3519 					   loff_t pos, unsigned len,
3520 					   unsigned flags,
3521 					   struct page **pagep,
3522 					   void **fsdata);
3523 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3524 					 unsigned len, unsigned copied,
3525 					 struct page *page);
3526 extern int ext4_try_add_inline_entry(handle_t *handle,
3527 				     struct ext4_filename *fname,
3528 				     struct inode *dir, struct inode *inode);
3529 extern int ext4_try_create_inline_dir(handle_t *handle,
3530 				      struct inode *parent,
3531 				      struct inode *inode);
3532 extern int ext4_read_inline_dir(struct file *filp,
3533 				struct dir_context *ctx,
3534 				int *has_inline_data);
3535 extern int ext4_inlinedir_to_tree(struct file *dir_file,
3536 				  struct inode *dir, ext4_lblk_t block,
3537 				  struct dx_hash_info *hinfo,
3538 				  __u32 start_hash, __u32 start_minor_hash,
3539 				  int *has_inline_data);
3540 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3541 					struct ext4_filename *fname,
3542 					struct ext4_dir_entry_2 **res_dir,
3543 					int *has_inline_data);
3544 extern int ext4_delete_inline_entry(handle_t *handle,
3545 				    struct inode *dir,
3546 				    struct ext4_dir_entry_2 *de_del,
3547 				    struct buffer_head *bh,
3548 				    int *has_inline_data);
3549 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3550 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3551 					struct ext4_dir_entry_2 **parent_de,
3552 					int *retval);
3553 extern int ext4_inline_data_fiemap(struct inode *inode,
3554 				   struct fiemap_extent_info *fieinfo,
3555 				   int *has_inline, __u64 start, __u64 len);
3556 
3557 struct iomap;
3558 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3559 
3560 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3561 
3562 extern int ext4_convert_inline_data(struct inode *inode);
3563 
3564 static inline int ext4_has_inline_data(struct inode *inode)
3565 {
3566 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3567 	       EXT4_I(inode)->i_inline_off;
3568 }
3569 
3570 /* namei.c */
3571 extern const struct inode_operations ext4_dir_inode_operations;
3572 extern const struct inode_operations ext4_special_inode_operations;
3573 extern struct dentry *ext4_get_parent(struct dentry *child);
3574 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3575 				 struct ext4_dir_entry_2 *de,
3576 				 int blocksize, int csum_size,
3577 				 unsigned int parent_ino, int dotdot_real_len);
3578 extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
3579 					unsigned int blocksize);
3580 extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
3581 				      struct buffer_head *bh);
3582 extern int __ext4_unlink(handle_t *handle, struct inode *dir, const struct qstr *d_name,
3583 			 struct inode *inode);
3584 extern int __ext4_link(struct inode *dir, struct inode *inode,
3585 		       struct dentry *dentry);
3586 
3587 #define S_SHIFT 12
3588 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3589 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3590 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3591 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3592 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3593 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3594 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3595 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3596 };
3597 
3598 static inline void ext4_set_de_type(struct super_block *sb,
3599 				struct ext4_dir_entry_2 *de,
3600 				umode_t mode) {
3601 	if (ext4_has_feature_filetype(sb))
3602 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3603 }
3604 
3605 /* readpages.c */
3606 extern int ext4_mpage_readpages(struct inode *inode,
3607 		struct readahead_control *rac, struct page *page);
3608 extern int __init ext4_init_post_read_processing(void);
3609 extern void ext4_exit_post_read_processing(void);
3610 
3611 /* symlink.c */
3612 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3613 extern const struct inode_operations ext4_symlink_inode_operations;
3614 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3615 
3616 /* sysfs.c */
3617 extern int ext4_register_sysfs(struct super_block *sb);
3618 extern void ext4_unregister_sysfs(struct super_block *sb);
3619 extern int __init ext4_init_sysfs(void);
3620 extern void ext4_exit_sysfs(void);
3621 
3622 /* block_validity */
3623 extern void ext4_release_system_zone(struct super_block *sb);
3624 extern int ext4_setup_system_zone(struct super_block *sb);
3625 extern int __init ext4_init_system_zone(void);
3626 extern void ext4_exit_system_zone(void);
3627 extern int ext4_inode_block_valid(struct inode *inode,
3628 				  ext4_fsblk_t start_blk,
3629 				  unsigned int count);
3630 extern int ext4_check_blockref(const char *, unsigned int,
3631 			       struct inode *, __le32 *, unsigned int);
3632 
3633 /* extents.c */
3634 struct ext4_ext_path;
3635 struct ext4_extent;
3636 
3637 /*
3638  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3639  * __le32.
3640  */
3641 #define EXT_MAX_BLOCKS	0xffffffff
3642 
3643 extern void ext4_ext_tree_init(handle_t *handle, struct inode *inode);
3644 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3645 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3646 			       struct ext4_map_blocks *map, int flags);
3647 extern int ext4_ext_truncate(handle_t *, struct inode *);
3648 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3649 				 ext4_lblk_t end);
3650 extern void ext4_ext_init(struct super_block *);
3651 extern void ext4_ext_release(struct super_block *);
3652 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3653 			  loff_t len);
3654 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3655 					  loff_t offset, ssize_t len);
3656 extern int ext4_convert_unwritten_io_end_vec(handle_t *handle,
3657 					     ext4_io_end_t *io_end);
3658 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3659 			   struct ext4_map_blocks *map, int flags);
3660 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3661 						   int num,
3662 						   struct ext4_ext_path *path);
3663 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3664 				  struct ext4_ext_path **,
3665 				  struct ext4_extent *, int);
3666 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3667 					      struct ext4_ext_path **,
3668 					      int flags);
3669 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3670 extern int ext4_ext_check_inode(struct inode *inode);
3671 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3672 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3673 			__u64 start, __u64 len);
3674 extern int ext4_get_es_cache(struct inode *inode,
3675 			     struct fiemap_extent_info *fieinfo,
3676 			     __u64 start, __u64 len);
3677 extern int ext4_ext_precache(struct inode *inode);
3678 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3679 				struct inode *inode2, ext4_lblk_t lblk1,
3680 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3681 			     int mark_unwritten,int *err);
3682 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3683 extern int ext4_datasem_ensure_credits(handle_t *handle, struct inode *inode,
3684 				       int check_cred, int restart_cred,
3685 				       int revoke_cred);
3686 extern void ext4_ext_replay_shrink_inode(struct inode *inode, ext4_lblk_t end);
3687 extern int ext4_ext_replay_set_iblocks(struct inode *inode);
3688 extern int ext4_ext_replay_update_ex(struct inode *inode, ext4_lblk_t start,
3689 		int len, int unwritten, ext4_fsblk_t pblk);
3690 extern int ext4_ext_clear_bb(struct inode *inode);
3691 
3692 
3693 /* move_extent.c */
3694 extern void ext4_double_down_write_data_sem(struct inode *first,
3695 					    struct inode *second);
3696 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3697 					  struct inode *donor_inode);
3698 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3699 			     __u64 start_orig, __u64 start_donor,
3700 			     __u64 len, __u64 *moved_len);
3701 
3702 /* page-io.c */
3703 extern int __init ext4_init_pageio(void);
3704 extern void ext4_exit_pageio(void);
3705 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3706 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3707 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3708 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3709 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3710 				struct writeback_control *wbc);
3711 extern void ext4_end_io_rsv_work(struct work_struct *work);
3712 extern void ext4_io_submit(struct ext4_io_submit *io);
3713 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3714 			       struct page *page,
3715 			       int len,
3716 			       bool keep_towrite);
3717 extern struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end);
3718 extern struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end);
3719 
3720 /* mmp.c */
3721 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3722 
3723 /* verity.c */
3724 extern const struct fsverity_operations ext4_verityops;
3725 
3726 /*
3727  * Add new method to test whether block and inode bitmaps are properly
3728  * initialized. With uninit_bg reading the block from disk is not enough
3729  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3730  */
3731 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3732 
3733 static inline int bitmap_uptodate(struct buffer_head *bh)
3734 {
3735 	return (buffer_uptodate(bh) &&
3736 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3737 }
3738 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3739 {
3740 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3741 }
3742 
3743 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3744 
3745 /* For ioend & aio unwritten conversion wait queues */
3746 #define EXT4_WQ_HASH_SZ		37
3747 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3748 					    EXT4_WQ_HASH_SZ])
3749 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3750 
3751 extern int ext4_resize_begin(struct super_block *sb);
3752 extern void ext4_resize_end(struct super_block *sb);
3753 
3754 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3755 					      struct ext4_io_end *io_end)
3756 {
3757 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3758 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3759 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3760 	}
3761 }
3762 
3763 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3764 {
3765 	struct inode *inode = io_end->inode;
3766 
3767 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3768 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3769 		/* Wake up anyone waiting on unwritten extent conversion */
3770 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3771 			wake_up_all(ext4_ioend_wq(inode));
3772 	}
3773 }
3774 
3775 extern const struct iomap_ops ext4_iomap_ops;
3776 extern const struct iomap_ops ext4_iomap_overwrite_ops;
3777 extern const struct iomap_ops ext4_iomap_report_ops;
3778 
3779 static inline int ext4_buffer_uptodate(struct buffer_head *bh)
3780 {
3781 	/*
3782 	 * If the buffer has the write error flag, we have failed
3783 	 * to write out data in the block.  In this  case, we don't
3784 	 * have to read the block because we may read the old data
3785 	 * successfully.
3786 	 */
3787 	if (!buffer_uptodate(bh) && buffer_write_io_error(bh))
3788 		set_buffer_uptodate(bh);
3789 	return buffer_uptodate(bh);
3790 }
3791 
3792 #endif	/* __KERNEL__ */
3793 
3794 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3795 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3796 
3797 #endif	/* _EXT4_H */
3798