xref: /openbmc/linux/fs/ext4/ext4.h (revision cf21eb6a)
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/refcount.h>
21 #include <linux/types.h>
22 #include <linux/blkdev.h>
23 #include <linux/magic.h>
24 #include <linux/jbd2.h>
25 #include <linux/quota.h>
26 #include <linux/rwsem.h>
27 #include <linux/rbtree.h>
28 #include <linux/seqlock.h>
29 #include <linux/mutex.h>
30 #include <linux/timer.h>
31 #include <linux/wait.h>
32 #include <linux/sched/signal.h>
33 #include <linux/blockgroup_lock.h>
34 #include <linux/percpu_counter.h>
35 #include <linux/ratelimit.h>
36 #include <crypto/hash.h>
37 #include <linux/falloc.h>
38 #include <linux/percpu-rwsem.h>
39 #include <linux/fiemap.h>
40 #ifdef __KERNEL__
41 #include <linux/compat.h>
42 #endif
43 #include <uapi/linux/ext4.h>
44 
45 #include <linux/fscrypt.h>
46 #include <linux/fsverity.h>
47 
48 #include <linux/compiler.h>
49 
50 /*
51  * The fourth extended filesystem constants/structures
52  */
53 
54 /*
55  * with AGGRESSIVE_CHECK allocator runs consistency checks over
56  * structures. these checks slow things down a lot
57  */
58 #define AGGRESSIVE_CHECK__
59 
60 /*
61  * with DOUBLE_CHECK defined mballoc creates persistent in-core
62  * bitmaps, maintains and uses them to check for double allocations
63  */
64 #define DOUBLE_CHECK__
65 
66 /*
67  * Define EXT4FS_DEBUG to produce debug messages
68  */
69 #undef EXT4FS_DEBUG
70 
71 /*
72  * Debug code
73  */
74 #ifdef EXT4FS_DEBUG
75 #define ext4_debug(f, a...)						\
76 	do {								\
77 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
78 			__FILE__, __LINE__, __func__);			\
79 		printk(KERN_DEBUG f, ## a);				\
80 	} while (0)
81 #else
82 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
83 #endif
84 
85  /*
86   * Turn on EXT_DEBUG to enable ext4_ext_show_path/leaf/move in extents.c
87   */
88 #define EXT_DEBUG__
89 
90 /*
91  * Dynamic printk for controlled extents debugging.
92  */
93 #ifdef CONFIG_EXT4_DEBUG
94 #define ext_debug(ino, fmt, ...)					\
95 	pr_debug("[%s/%d] EXT4-fs (%s): ino %lu: (%s, %d): %s:" fmt,	\
96 		 current->comm, task_pid_nr(current),			\
97 		 ino->i_sb->s_id, ino->i_ino, __FILE__, __LINE__,	\
98 		 __func__, ##__VA_ARGS__)
99 #else
100 #define ext_debug(ino, fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
101 #endif
102 
103 #define ASSERT(assert)						\
104 do {									\
105 	if (unlikely(!(assert))) {					\
106 		printk(KERN_EMERG					\
107 		       "Assertion failure in %s() at %s:%d: '%s'\n",	\
108 		       __func__, __FILE__, __LINE__, #assert);		\
109 		BUG();							\
110 	}								\
111 } while (0)
112 
113 /* data type for block offset of block group */
114 typedef int ext4_grpblk_t;
115 
116 /* data type for filesystem-wide blocks number */
117 typedef unsigned long long ext4_fsblk_t;
118 
119 /* data type for file logical block number */
120 typedef __u32 ext4_lblk_t;
121 
122 /* data type for block group number */
123 typedef unsigned int ext4_group_t;
124 
125 enum SHIFT_DIRECTION {
126 	SHIFT_LEFT = 0,
127 	SHIFT_RIGHT,
128 };
129 
130 /*
131  * For each criteria, mballoc has slightly different way of finding
132  * the required blocks nad usually, higher the criteria the slower the
133  * allocation.  We start at lower criterias and keep falling back to
134  * higher ones if we are not able to find any blocks.  Lower (earlier)
135  * criteria are faster.
136  */
137 enum criteria {
138 	/*
139 	 * Used when number of blocks needed is a power of 2. This
140 	 * doesn't trigger any disk IO except prefetch and is the
141 	 * fastest criteria.
142 	 */
143 	CR_POWER2_ALIGNED,
144 
145 	/*
146 	 * Tries to lookup in-memory data structures to find the most
147 	 * suitable group that satisfies goal request. No disk IO
148 	 * except block prefetch.
149 	 */
150 	CR_GOAL_LEN_FAST,
151 
152         /*
153 	 * Same as CR_GOAL_LEN_FAST but is allowed to reduce the goal
154          * length to the best available length for faster allocation.
155 	 */
156 	CR_BEST_AVAIL_LEN,
157 
158 	/*
159 	 * Reads each block group sequentially, performing disk IO if
160 	 * necessary, to find find_suitable block group. Tries to
161 	 * allocate goal length but might trim the request if nothing
162 	 * is found after enough tries.
163 	 */
164 	CR_GOAL_LEN_SLOW,
165 
166 	/*
167 	 * Finds the first free set of blocks and allocates
168 	 * those. This is only used in rare cases when
169 	 * CR_GOAL_LEN_SLOW also fails to allocate anything.
170 	 */
171 	CR_ANY_FREE,
172 
173 	/*
174 	 * Number of criterias defined.
175 	 */
176 	EXT4_MB_NUM_CRS
177 };
178 
179 /*
180  * Flags used in mballoc's allocation_context flags field.
181  *
182  * Also used to show what's going on for debugging purposes when the
183  * flag field is exported via the traceport interface
184  */
185 
186 /* prefer goal again. length */
187 #define EXT4_MB_HINT_MERGE		0x0001
188 /* blocks already reserved */
189 #define EXT4_MB_HINT_RESERVED		0x0002
190 /* metadata is being allocated */
191 #define EXT4_MB_HINT_METADATA		0x0004
192 /* first blocks in the file */
193 #define EXT4_MB_HINT_FIRST		0x0008
194 /* search for the best chunk */
195 #define EXT4_MB_HINT_BEST		0x0010
196 /* data is being allocated */
197 #define EXT4_MB_HINT_DATA		0x0020
198 /* don't preallocate (for tails) */
199 #define EXT4_MB_HINT_NOPREALLOC		0x0040
200 /* allocate for locality group */
201 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
202 /* allocate goal blocks or none */
203 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
204 /* goal is meaningful */
205 #define EXT4_MB_HINT_TRY_GOAL		0x0200
206 /* blocks already pre-reserved by delayed allocation */
207 #define EXT4_MB_DELALLOC_RESERVED	0x0400
208 /* We are doing stream allocation */
209 #define EXT4_MB_STREAM_ALLOC		0x0800
210 /* Use reserved root blocks if needed */
211 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
212 /* Use blocks from reserved pool */
213 #define EXT4_MB_USE_RESERVED		0x2000
214 /* Do strict check for free blocks while retrying block allocation */
215 #define EXT4_MB_STRICT_CHECK		0x4000
216 /* Large fragment size list lookup succeeded at least once for cr = 0 */
217 #define EXT4_MB_CR_POWER2_ALIGNED_OPTIMIZED		0x8000
218 /* Avg fragment size rb tree lookup succeeded at least once for cr = 1 */
219 #define EXT4_MB_CR_GOAL_LEN_FAST_OPTIMIZED		0x00010000
220 /* Avg fragment size rb tree lookup succeeded at least once for cr = 1.5 */
221 #define EXT4_MB_CR_BEST_AVAIL_LEN_OPTIMIZED		0x00020000
222 
223 struct ext4_allocation_request {
224 	/* target inode for block we're allocating */
225 	struct inode *inode;
226 	/* how many blocks we want to allocate */
227 	unsigned int len;
228 	/* logical block in target inode */
229 	ext4_lblk_t logical;
230 	/* the closest logical allocated block to the left */
231 	ext4_lblk_t lleft;
232 	/* the closest logical allocated block to the right */
233 	ext4_lblk_t lright;
234 	/* phys. target (a hint) */
235 	ext4_fsblk_t goal;
236 	/* phys. block for the closest logical allocated block to the left */
237 	ext4_fsblk_t pleft;
238 	/* phys. block for the closest logical allocated block to the right */
239 	ext4_fsblk_t pright;
240 	/* flags. see above EXT4_MB_HINT_* */
241 	unsigned int flags;
242 };
243 
244 /*
245  * Logical to physical block mapping, used by ext4_map_blocks()
246  *
247  * This structure is used to pass requests into ext4_map_blocks() as
248  * well as to store the information returned by ext4_map_blocks().  It
249  * takes less room on the stack than a struct buffer_head.
250  */
251 #define EXT4_MAP_NEW		BIT(BH_New)
252 #define EXT4_MAP_MAPPED		BIT(BH_Mapped)
253 #define EXT4_MAP_UNWRITTEN	BIT(BH_Unwritten)
254 #define EXT4_MAP_BOUNDARY	BIT(BH_Boundary)
255 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
256 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
257 
258 struct ext4_map_blocks {
259 	ext4_fsblk_t m_pblk;
260 	ext4_lblk_t m_lblk;
261 	unsigned int m_len;
262 	unsigned int m_flags;
263 };
264 
265 /*
266  * Block validity checking, system zone rbtree.
267  */
268 struct ext4_system_blocks {
269 	struct rb_root root;
270 	struct rcu_head rcu;
271 };
272 
273 /*
274  * Flags for ext4_io_end->flags
275  */
276 #define	EXT4_IO_END_UNWRITTEN	0x0001
277 
278 struct ext4_io_end_vec {
279 	struct list_head list;		/* list of io_end_vec */
280 	loff_t offset;			/* offset in the file */
281 	ssize_t size;			/* size of the extent */
282 };
283 
284 /*
285  * For converting unwritten extents on a work queue. 'handle' is used for
286  * buffered writeback.
287  */
288 typedef struct ext4_io_end {
289 	struct list_head	list;		/* per-file finished IO list */
290 	handle_t		*handle;	/* handle reserved for extent
291 						 * conversion */
292 	struct inode		*inode;		/* file being written to */
293 	struct bio		*bio;		/* Linked list of completed
294 						 * bios covering the extent */
295 	unsigned int		flag;		/* unwritten or not */
296 	refcount_t		count;		/* reference counter */
297 	struct list_head	list_vec;	/* list of ext4_io_end_vec */
298 } ext4_io_end_t;
299 
300 struct ext4_io_submit {
301 	struct writeback_control *io_wbc;
302 	struct bio		*io_bio;
303 	ext4_io_end_t		*io_end;
304 	sector_t		io_next_block;
305 };
306 
307 /*
308  * Special inodes numbers
309  */
310 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
311 #define EXT4_ROOT_INO		 2	/* Root inode */
312 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
313 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
314 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
315 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
316 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
317 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
318 
319 /* First non-reserved inode for old ext4 filesystems */
320 #define EXT4_GOOD_OLD_FIRST_INO	11
321 
322 /*
323  * Maximal count of links to a file
324  */
325 #define EXT4_LINK_MAX		65000
326 
327 /*
328  * Macro-instructions used to manage several block sizes
329  */
330 #define EXT4_MIN_BLOCK_SIZE		1024
331 #define	EXT4_MAX_BLOCK_SIZE		65536
332 #define EXT4_MIN_BLOCK_LOG_SIZE		10
333 #define EXT4_MAX_BLOCK_LOG_SIZE		16
334 #define EXT4_MAX_CLUSTER_LOG_SIZE	30
335 #ifdef __KERNEL__
336 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
337 #else
338 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
339 #endif
340 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
341 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
342 					 EXT4_SB(s)->s_cluster_bits)
343 #ifdef __KERNEL__
344 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
345 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
346 #else
347 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
348 #endif
349 #ifdef __KERNEL__
350 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
351 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
352 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
353 #else
354 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
355 				 EXT4_GOOD_OLD_INODE_SIZE : \
356 				 (s)->s_inode_size)
357 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
358 				 EXT4_GOOD_OLD_FIRST_INO : \
359 				 (s)->s_first_ino)
360 #endif
361 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
362 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
363 	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
364 								  blkbits))
365 
366 /* Translate a block number to a cluster number */
367 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
368 /* Translate a cluster number to a block number */
369 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
370 /* Translate # of blks to # of clusters */
371 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
372 				 (sbi)->s_cluster_bits)
373 /* Mask out the low bits to get the starting block of the cluster */
374 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
375 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
376 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
377 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
378 /* Fill in the low bits to get the last block of the cluster */
379 #define EXT4_LBLK_CFILL(sbi, lblk) ((lblk) |				\
380 				    ((ext4_lblk_t) (sbi)->s_cluster_ratio - 1))
381 /* Get the cluster offset */
382 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
383 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
384 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
385 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
386 
387 /*
388  * Structure of a blocks group descriptor
389  */
390 struct ext4_group_desc
391 {
392 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
393 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
394 	__le32	bg_inode_table_lo;	/* Inodes table block */
395 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
396 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
397 	__le16	bg_used_dirs_count_lo;	/* Directories count */
398 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
399 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
400 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
401 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
402 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
403 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
404 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
405 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
406 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
407 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
408 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
409 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
410 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
411 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
412 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
413 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
414 	__u32   bg_reserved;
415 };
416 
417 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
418 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
419 	 sizeof(__le16))
420 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
421 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
422 	 sizeof(__le16))
423 
424 /*
425  * Structure of a flex block group info
426  */
427 
428 struct flex_groups {
429 	atomic64_t	free_clusters;
430 	atomic_t	free_inodes;
431 	atomic_t	used_dirs;
432 };
433 
434 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
435 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
436 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
437 
438 /*
439  * Macro-instructions used to manage group descriptors
440  */
441 #define EXT4_MIN_DESC_SIZE		32
442 #define EXT4_MIN_DESC_SIZE_64BIT	64
443 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
444 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
445 #ifdef __KERNEL__
446 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
447 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
448 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
449 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
450 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
451 #else
452 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
453 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
454 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
455 #endif
456 
457 /*
458  * Constants relative to the data blocks
459  */
460 #define	EXT4_NDIR_BLOCKS		12
461 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
462 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
463 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
464 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
465 
466 /*
467  * Inode flags
468  */
469 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
470 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
471 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
472 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
473 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
474 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
475 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
476 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
477 /* Reserved for compression usage... */
478 #define EXT4_DIRTY_FL			0x00000100
479 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
480 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
481 	/* nb: was previously EXT2_ECOMPR_FL */
482 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
483 /* End compression flags --- maybe not all used */
484 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
485 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
486 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
487 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
488 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
489 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
490 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
491 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
492 #define EXT4_VERITY_FL			0x00100000 /* Verity protected inode */
493 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
494 /* 0x00400000 was formerly EXT4_EOFBLOCKS_FL */
495 
496 #define EXT4_DAX_FL			0x02000000 /* Inode is DAX */
497 
498 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
499 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
500 #define EXT4_CASEFOLD_FL		0x40000000 /* Casefolded directory */
501 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
502 
503 /* User modifiable flags */
504 #define EXT4_FL_USER_MODIFIABLE		(EXT4_SECRM_FL | \
505 					 EXT4_UNRM_FL | \
506 					 EXT4_COMPR_FL | \
507 					 EXT4_SYNC_FL | \
508 					 EXT4_IMMUTABLE_FL | \
509 					 EXT4_APPEND_FL | \
510 					 EXT4_NODUMP_FL | \
511 					 EXT4_NOATIME_FL | \
512 					 EXT4_JOURNAL_DATA_FL | \
513 					 EXT4_NOTAIL_FL | \
514 					 EXT4_DIRSYNC_FL | \
515 					 EXT4_TOPDIR_FL | \
516 					 EXT4_EXTENTS_FL | \
517 					 0x00400000 /* EXT4_EOFBLOCKS_FL */ | \
518 					 EXT4_DAX_FL | \
519 					 EXT4_PROJINHERIT_FL | \
520 					 EXT4_CASEFOLD_FL)
521 
522 /* User visible flags */
523 #define EXT4_FL_USER_VISIBLE		(EXT4_FL_USER_MODIFIABLE | \
524 					 EXT4_DIRTY_FL | \
525 					 EXT4_COMPRBLK_FL | \
526 					 EXT4_NOCOMPR_FL | \
527 					 EXT4_ENCRYPT_FL | \
528 					 EXT4_INDEX_FL | \
529 					 EXT4_VERITY_FL | \
530 					 EXT4_INLINE_DATA_FL)
531 
532 /* Flags that should be inherited by new inodes from their parent. */
533 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
534 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
535 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
536 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
537 			   EXT4_PROJINHERIT_FL | EXT4_CASEFOLD_FL |\
538 			   EXT4_DAX_FL)
539 
540 /* Flags that are appropriate for regular files (all but dir-specific ones). */
541 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL | EXT4_CASEFOLD_FL |\
542 			   EXT4_PROJINHERIT_FL))
543 
544 /* Flags that are appropriate for non-directories/regular files. */
545 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
546 
547 /* The only flags that should be swapped */
548 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
549 
550 /* Flags which are mutually exclusive to DAX */
551 #define EXT4_DAX_MUT_EXCL (EXT4_VERITY_FL | EXT4_ENCRYPT_FL |\
552 			   EXT4_JOURNAL_DATA_FL | EXT4_INLINE_DATA_FL)
553 
554 /* Mask out flags that are inappropriate for the given type of inode. */
555 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
556 {
557 	if (S_ISDIR(mode))
558 		return flags;
559 	else if (S_ISREG(mode))
560 		return flags & EXT4_REG_FLMASK;
561 	else
562 		return flags & EXT4_OTHER_FLMASK;
563 }
564 
565 /*
566  * Inode flags used for atomic set/get
567  */
568 enum {
569 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
570 	EXT4_INODE_UNRM		= 1,	/* Undelete */
571 	EXT4_INODE_COMPR	= 2,	/* Compress file */
572 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
573 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
574 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
575 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
576 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
577 /* Reserved for compression usage... */
578 	EXT4_INODE_DIRTY	= 8,
579 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
580 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
581 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
582 /* End compression flags --- maybe not all used */
583 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
584 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
585 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
586 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
587 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
588 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
589 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
590 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
591 	EXT4_INODE_VERITY	= 20,	/* Verity protected inode */
592 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
593 /* 22 was formerly EXT4_INODE_EOFBLOCKS */
594 	EXT4_INODE_DAX		= 25,	/* Inode is DAX */
595 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
596 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
597 	EXT4_INODE_CASEFOLD	= 30,	/* Casefolded directory */
598 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
599 };
600 
601 /*
602  * Since it's pretty easy to mix up bit numbers and hex values, we use a
603  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
604  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
605  * any extra space in the compiled kernel image, otherwise, the build will fail.
606  * It's important that these values are the same, since we are using
607  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
608  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
609  * values found in ext2, ext3 and ext4 filesystems, and of course the values
610  * defined in e2fsprogs.
611  *
612  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
613  */
614 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1U << EXT4_INODE_##FLAG))
615 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
616 
617 static inline void ext4_check_flag_values(void)
618 {
619 	CHECK_FLAG_VALUE(SECRM);
620 	CHECK_FLAG_VALUE(UNRM);
621 	CHECK_FLAG_VALUE(COMPR);
622 	CHECK_FLAG_VALUE(SYNC);
623 	CHECK_FLAG_VALUE(IMMUTABLE);
624 	CHECK_FLAG_VALUE(APPEND);
625 	CHECK_FLAG_VALUE(NODUMP);
626 	CHECK_FLAG_VALUE(NOATIME);
627 	CHECK_FLAG_VALUE(DIRTY);
628 	CHECK_FLAG_VALUE(COMPRBLK);
629 	CHECK_FLAG_VALUE(NOCOMPR);
630 	CHECK_FLAG_VALUE(ENCRYPT);
631 	CHECK_FLAG_VALUE(INDEX);
632 	CHECK_FLAG_VALUE(IMAGIC);
633 	CHECK_FLAG_VALUE(JOURNAL_DATA);
634 	CHECK_FLAG_VALUE(NOTAIL);
635 	CHECK_FLAG_VALUE(DIRSYNC);
636 	CHECK_FLAG_VALUE(TOPDIR);
637 	CHECK_FLAG_VALUE(HUGE_FILE);
638 	CHECK_FLAG_VALUE(EXTENTS);
639 	CHECK_FLAG_VALUE(VERITY);
640 	CHECK_FLAG_VALUE(EA_INODE);
641 	CHECK_FLAG_VALUE(INLINE_DATA);
642 	CHECK_FLAG_VALUE(PROJINHERIT);
643 	CHECK_FLAG_VALUE(CASEFOLD);
644 	CHECK_FLAG_VALUE(RESERVED);
645 }
646 
647 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
648 struct compat_ext4_new_group_input {
649 	u32 group;
650 	compat_u64 block_bitmap;
651 	compat_u64 inode_bitmap;
652 	compat_u64 inode_table;
653 	u32 blocks_count;
654 	u16 reserved_blocks;
655 	u16 unused;
656 };
657 #endif
658 
659 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
660 struct ext4_new_group_data {
661 	__u32 group;
662 	__u64 block_bitmap;
663 	__u64 inode_bitmap;
664 	__u64 inode_table;
665 	__u32 blocks_count;
666 	__u16 reserved_blocks;
667 	__u16 mdata_blocks;
668 	__u32 free_clusters_count;
669 };
670 
671 /* Indexes used to index group tables in ext4_new_group_data */
672 enum {
673 	BLOCK_BITMAP = 0,	/* block bitmap */
674 	INODE_BITMAP,		/* inode bitmap */
675 	INODE_TABLE,		/* inode tables */
676 	GROUP_TABLE_COUNT,
677 };
678 
679 /*
680  * Flags used by ext4_map_blocks()
681  */
682 	/* Allocate any needed blocks and/or convert an unwritten
683 	   extent to be an initialized ext4 */
684 #define EXT4_GET_BLOCKS_CREATE			0x0001
685 	/* Request the creation of an unwritten extent */
686 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
687 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
688 						 EXT4_GET_BLOCKS_CREATE)
689 	/* Caller is from the delayed allocation writeout path
690 	 * finally doing the actual allocation of delayed blocks */
691 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
692 	/* caller is from the direct IO path, request to creation of an
693 	unwritten extents if not allocated, split the unwritten
694 	extent if blocks has been preallocated already*/
695 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
696 #define EXT4_GET_BLOCKS_CONVERT			0x0010
697 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
698 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
699 	/* Convert extent to initialized after IO complete */
700 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
701 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
702 	/* Eventual metadata allocation (due to growing extent tree)
703 	 * should not fail, so try to use reserved blocks for that.*/
704 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
705 	/* Don't normalize allocation size (used for fallocate) */
706 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
707 	/* Convert written extents to unwritten */
708 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
709 	/* Write zeros to newly created written extents */
710 #define EXT4_GET_BLOCKS_ZERO			0x0200
711 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
712 					EXT4_GET_BLOCKS_ZERO)
713 	/* Caller will submit data before dropping transaction handle. This
714 	 * allows jbd2 to avoid submitting data before commit. */
715 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
716 	/* Caller is in the atomic contex, find extent if it has been cached */
717 #define EXT4_GET_BLOCKS_CACHED_NOWAIT		0x0800
718 
719 /*
720  * The bit position of these flags must not overlap with any of the
721  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
722  * read_extent_tree_block(), ext4_split_extent_at(),
723  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
724  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
725  * caching the extents when reading from the extent tree while a
726  * truncate or punch hole operation is in progress.
727  */
728 #define EXT4_EX_NOCACHE				0x40000000
729 #define EXT4_EX_FORCE_CACHE			0x20000000
730 #define EXT4_EX_NOFAIL				0x10000000
731 
732 /*
733  * Flags used by ext4_free_blocks
734  */
735 #define EXT4_FREE_BLOCKS_METADATA		0x0001
736 #define EXT4_FREE_BLOCKS_FORGET			0x0002
737 #define EXT4_FREE_BLOCKS_VALIDATED		0x0004
738 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE		0x0008
739 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
740 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
741 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
742 
743 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
744 /*
745  * ioctl commands in 32 bit emulation
746  */
747 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
748 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
749 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
750 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
751 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
752 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
753 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
754 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
755 #endif
756 
757 /* Max physical block we can address w/o extents */
758 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
759 
760 /* Max logical block we can support */
761 #define EXT4_MAX_LOGICAL_BLOCK		0xFFFFFFFE
762 
763 /*
764  * Structure of an inode on the disk
765  */
766 struct ext4_inode {
767 	__le16	i_mode;		/* File mode */
768 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
769 	__le32	i_size_lo;	/* Size in bytes */
770 	__le32	i_atime;	/* Access time */
771 	__le32	i_ctime;	/* Inode Change time */
772 	__le32	i_mtime;	/* Modification time */
773 	__le32	i_dtime;	/* Deletion Time */
774 	__le16	i_gid;		/* Low 16 bits of Group Id */
775 	__le16	i_links_count;	/* Links count */
776 	__le32	i_blocks_lo;	/* Blocks count */
777 	__le32	i_flags;	/* File flags */
778 	union {
779 		struct {
780 			__le32  l_i_version;
781 		} linux1;
782 		struct {
783 			__u32  h_i_translator;
784 		} hurd1;
785 		struct {
786 			__u32  m_i_reserved1;
787 		} masix1;
788 	} osd1;				/* OS dependent 1 */
789 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
790 	__le32	i_generation;	/* File version (for NFS) */
791 	__le32	i_file_acl_lo;	/* File ACL */
792 	__le32	i_size_high;
793 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
794 	union {
795 		struct {
796 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
797 			__le16	l_i_file_acl_high;
798 			__le16	l_i_uid_high;	/* these 2 fields */
799 			__le16	l_i_gid_high;	/* were reserved2[0] */
800 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
801 			__le16	l_i_reserved;
802 		} linux2;
803 		struct {
804 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
805 			__u16	h_i_mode_high;
806 			__u16	h_i_uid_high;
807 			__u16	h_i_gid_high;
808 			__u32	h_i_author;
809 		} hurd2;
810 		struct {
811 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
812 			__le16	m_i_file_acl_high;
813 			__u32	m_i_reserved2[2];
814 		} masix2;
815 	} osd2;				/* OS dependent 2 */
816 	__le16	i_extra_isize;
817 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
818 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
819 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
820 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
821 	__le32  i_crtime;       /* File Creation time */
822 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
823 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
824 	__le32	i_projid;	/* Project ID */
825 };
826 
827 #define EXT4_EPOCH_BITS 2
828 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
829 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
830 
831 /*
832  * Extended fields will fit into an inode if the filesystem was formatted
833  * with large inodes (-I 256 or larger) and there are not currently any EAs
834  * consuming all of the available space. For new inodes we always reserve
835  * enough space for the kernel's known extended fields, but for inodes
836  * created with an old kernel this might not have been the case. None of
837  * the extended inode fields is critical for correct filesystem operation.
838  * This macro checks if a certain field fits in the inode. Note that
839  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
840  */
841 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
842 	((offsetof(typeof(*ext4_inode), field) +	\
843 	  sizeof((ext4_inode)->field))			\
844 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
845 	    (einode)->i_extra_isize))			\
846 
847 /*
848  * We use an encoding that preserves the times for extra epoch "00":
849  *
850  * extra  msb of                         adjust for signed
851  * epoch  32-bit                         32-bit tv_sec to
852  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
853  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
854  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
855  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
856  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
857  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
858  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
859  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
860  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
861  *
862  * Note that previous versions of the kernel on 64-bit systems would
863  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
864  * 1970.  e2fsck will correct this, assuming that it is run on the
865  * affected filesystem before 2242.
866  */
867 
868 static inline __le32 ext4_encode_extra_time(struct timespec64 ts)
869 {
870 	u32 extra = ((ts.tv_sec - (s32)ts.tv_sec) >> 32) & EXT4_EPOCH_MASK;
871 	return cpu_to_le32(extra | (ts.tv_nsec << EXT4_EPOCH_BITS));
872 }
873 
874 static inline struct timespec64 ext4_decode_extra_time(__le32 base,
875 						       __le32 extra)
876 {
877 	struct timespec64 ts = { .tv_sec = (signed)le32_to_cpu(base) };
878 
879 	if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK)))
880 		ts.tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
881 	ts.tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
882 	return ts;
883 }
884 
885 #define EXT4_INODE_SET_XTIME_VAL(xtime, inode, raw_inode, ts)			\
886 do {										\
887 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {	\
888 		(raw_inode)->xtime = cpu_to_le32((ts).tv_sec);			\
889 		(raw_inode)->xtime ## _extra = ext4_encode_extra_time(ts);	\
890 	} else									\
891 		(raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (ts).tv_sec, S32_MIN, S32_MAX));	\
892 } while (0)
893 
894 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)				\
895 	EXT4_INODE_SET_XTIME_VAL(xtime, inode, raw_inode, (inode)->xtime)
896 
897 #define EXT4_INODE_SET_CTIME(inode, raw_inode)					\
898 	EXT4_INODE_SET_XTIME_VAL(i_ctime, inode, raw_inode, inode_get_ctime(inode))
899 
900 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)				\
901 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))			\
902 		EXT4_INODE_SET_XTIME_VAL(xtime, &((einode)->vfs_inode),		\
903 					 raw_inode, (einode)->xtime)
904 
905 #define EXT4_INODE_GET_XTIME_VAL(xtime, inode, raw_inode)			\
906 	(EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra) ?	\
907 		ext4_decode_extra_time((raw_inode)->xtime,				\
908 				       (raw_inode)->xtime ## _extra) :		\
909 		(struct timespec64) {						\
910 			.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime)	\
911 		})
912 
913 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)				\
914 do {										\
915 	(inode)->xtime = EXT4_INODE_GET_XTIME_VAL(xtime, inode, raw_inode);	\
916 } while (0)
917 
918 #define EXT4_INODE_GET_CTIME(inode, raw_inode)					\
919 do {										\
920 	inode_set_ctime_to_ts(inode,						\
921 		EXT4_INODE_GET_XTIME_VAL(i_ctime, inode, raw_inode));		\
922 } while (0)
923 
924 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)				\
925 do {										\
926 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime)) 			\
927 		(einode)->xtime =						\
928 			EXT4_INODE_GET_XTIME_VAL(xtime, &(einode->vfs_inode),	\
929 						 raw_inode);			\
930 	else									\
931 		(einode)->xtime = (struct timespec64){0, 0};			\
932 } while (0)
933 
934 #define i_disk_version osd1.linux1.l_i_version
935 
936 #if defined(__KERNEL__) || defined(__linux__)
937 #define i_reserved1	osd1.linux1.l_i_reserved1
938 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
939 #define i_blocks_high	osd2.linux2.l_i_blocks_high
940 #define i_uid_low	i_uid
941 #define i_gid_low	i_gid
942 #define i_uid_high	osd2.linux2.l_i_uid_high
943 #define i_gid_high	osd2.linux2.l_i_gid_high
944 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
945 
946 #elif defined(__GNU__)
947 
948 #define i_translator	osd1.hurd1.h_i_translator
949 #define i_uid_high	osd2.hurd2.h_i_uid_high
950 #define i_gid_high	osd2.hurd2.h_i_gid_high
951 #define i_author	osd2.hurd2.h_i_author
952 
953 #elif defined(__masix__)
954 
955 #define i_reserved1	osd1.masix1.m_i_reserved1
956 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
957 #define i_reserved2	osd2.masix2.m_i_reserved2
958 
959 #endif /* defined(__KERNEL__) || defined(__linux__) */
960 
961 #include "extents_status.h"
962 #include "fast_commit.h"
963 
964 /*
965  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
966  *
967  * These are needed to avoid lockdep false positives when we need to
968  * allocate blocks to the quota inode during ext4_map_blocks(), while
969  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
970  * do quota tracking for the quota inode, this avoids deadlock (as
971  * well as infinite recursion, since it isn't turtles all the way
972  * down...)
973  *
974  *  I_DATA_SEM_NORMAL - Used for most inodes
975  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
976  *			  where the second inode has larger inode number
977  *			  than the first
978  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
979  *  I_DATA_SEM_EA     - Used for ea_inodes only
980  */
981 enum {
982 	I_DATA_SEM_NORMAL = 0,
983 	I_DATA_SEM_OTHER,
984 	I_DATA_SEM_QUOTA,
985 	I_DATA_SEM_EA
986 };
987 
988 
989 /*
990  * fourth extended file system inode data in memory
991  */
992 struct ext4_inode_info {
993 	__le32	i_data[15];	/* unconverted */
994 	__u32	i_dtime;
995 	ext4_fsblk_t	i_file_acl;
996 
997 	/*
998 	 * i_block_group is the number of the block group which contains
999 	 * this file's inode.  Constant across the lifetime of the inode,
1000 	 * it is used for making block allocation decisions - we try to
1001 	 * place a file's data blocks near its inode block, and new inodes
1002 	 * near to their parent directory's inode.
1003 	 */
1004 	ext4_group_t	i_block_group;
1005 	ext4_lblk_t	i_dir_start_lookup;
1006 #if (BITS_PER_LONG < 64)
1007 	unsigned long	i_state_flags;		/* Dynamic state flags */
1008 #endif
1009 	unsigned long	i_flags;
1010 
1011 	/*
1012 	 * Extended attributes can be read independently of the main file
1013 	 * data. Taking i_rwsem even when reading would cause contention
1014 	 * between readers of EAs and writers of regular file data, so
1015 	 * instead we synchronize on xattr_sem when reading or changing
1016 	 * EAs.
1017 	 */
1018 	struct rw_semaphore xattr_sem;
1019 
1020 	/*
1021 	 * Inodes with EXT4_STATE_ORPHAN_FILE use i_orphan_idx. Otherwise
1022 	 * i_orphan is used.
1023 	 */
1024 	union {
1025 		struct list_head i_orphan;	/* unlinked but open inodes */
1026 		unsigned int i_orphan_idx;	/* Index in orphan file */
1027 	};
1028 
1029 	/* Fast commit related info */
1030 
1031 	/* For tracking dentry create updates */
1032 	struct list_head i_fc_dilist;
1033 	struct list_head i_fc_list;	/*
1034 					 * inodes that need fast commit
1035 					 * protected by sbi->s_fc_lock.
1036 					 */
1037 
1038 	/* Start of lblk range that needs to be committed in this fast commit */
1039 	ext4_lblk_t i_fc_lblk_start;
1040 
1041 	/* End of lblk range that needs to be committed in this fast commit */
1042 	ext4_lblk_t i_fc_lblk_len;
1043 
1044 	/* Number of ongoing updates on this inode */
1045 	atomic_t  i_fc_updates;
1046 
1047 	/* Fast commit wait queue for this inode */
1048 	wait_queue_head_t i_fc_wait;
1049 
1050 	/* Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len */
1051 	struct mutex i_fc_lock;
1052 
1053 	/*
1054 	 * i_disksize keeps track of what the inode size is ON DISK, not
1055 	 * in memory.  During truncate, i_size is set to the new size by
1056 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
1057 	 * set i_disksize to 0 until the truncate is actually under way.
1058 	 *
1059 	 * The intent is that i_disksize always represents the blocks which
1060 	 * are used by this file.  This allows recovery to restart truncate
1061 	 * on orphans if we crash during truncate.  We actually write i_disksize
1062 	 * into the on-disk inode when writing inodes out, instead of i_size.
1063 	 *
1064 	 * The only time when i_disksize and i_size may be different is when
1065 	 * a truncate is in progress.  The only things which change i_disksize
1066 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
1067 	 */
1068 	loff_t	i_disksize;
1069 
1070 	/*
1071 	 * i_data_sem is for serialising ext4_truncate() against
1072 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
1073 	 * data tree are chopped off during truncate. We can't do that in
1074 	 * ext4 because whenever we perform intermediate commits during
1075 	 * truncate, the inode and all the metadata blocks *must* be in a
1076 	 * consistent state which allows truncation of the orphans to restart
1077 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
1078 	 * by other means, so we have i_data_sem.
1079 	 */
1080 	struct rw_semaphore i_data_sem;
1081 	struct inode vfs_inode;
1082 	struct jbd2_inode *jinode;
1083 
1084 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
1085 
1086 	/*
1087 	 * File creation time. Its function is same as that of
1088 	 * struct timespec64 i_{a,c,m}time in the generic inode.
1089 	 */
1090 	struct timespec64 i_crtime;
1091 
1092 	/* mballoc */
1093 	atomic_t i_prealloc_active;
1094 	struct rb_root i_prealloc_node;
1095 	rwlock_t i_prealloc_lock;
1096 
1097 	/* extents status tree */
1098 	struct ext4_es_tree i_es_tree;
1099 	rwlock_t i_es_lock;
1100 	struct list_head i_es_list;
1101 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1102 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1103 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1104 					   extents to shrink. Protected by
1105 					   i_es_lock  */
1106 
1107 	/* ialloc */
1108 	ext4_group_t	i_last_alloc_group;
1109 
1110 	/* allocation reservation info for delalloc */
1111 	/* In case of bigalloc, this refer to clusters rather than blocks */
1112 	unsigned int i_reserved_data_blocks;
1113 
1114 	/* pending cluster reservations for bigalloc file systems */
1115 	struct ext4_pending_tree i_pending_tree;
1116 
1117 	/* on-disk additional length */
1118 	__u16 i_extra_isize;
1119 
1120 	/* Indicate the inline data space. */
1121 	u16 i_inline_off;
1122 	u16 i_inline_size;
1123 
1124 #ifdef CONFIG_QUOTA
1125 	/* quota space reservation, managed internally by quota code */
1126 	qsize_t i_reserved_quota;
1127 #endif
1128 
1129 	/* Lock protecting lists below */
1130 	spinlock_t i_completed_io_lock;
1131 	/*
1132 	 * Completed IOs that need unwritten extents handling and have
1133 	 * transaction reserved
1134 	 */
1135 	struct list_head i_rsv_conversion_list;
1136 	struct work_struct i_rsv_conversion_work;
1137 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1138 
1139 	spinlock_t i_block_reservation_lock;
1140 
1141 	/*
1142 	 * Transactions that contain inode's metadata needed to complete
1143 	 * fsync and fdatasync, respectively.
1144 	 */
1145 	tid_t i_sync_tid;
1146 	tid_t i_datasync_tid;
1147 
1148 #ifdef CONFIG_QUOTA
1149 	struct dquot __rcu *i_dquot[MAXQUOTAS];
1150 #endif
1151 
1152 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1153 	__u32 i_csum_seed;
1154 
1155 	kprojid_t i_projid;
1156 };
1157 
1158 /*
1159  * File system states
1160  */
1161 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1162 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1163 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1164 #define EXT4_FC_REPLAY			0x0020	/* Fast commit replay ongoing */
1165 
1166 /*
1167  * Misc. filesystem flags
1168  */
1169 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1170 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1171 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1172 
1173 /*
1174  * Mount flags set via mount options or defaults
1175  */
1176 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1177 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1178 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1179 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1180 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1181 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1182 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1183 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1184 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1185 #ifdef CONFIG_FS_DAX
1186 #define EXT4_MOUNT_DAX_ALWAYS		0x00200	/* Direct Access */
1187 #else
1188 #define EXT4_MOUNT_DAX_ALWAYS		0
1189 #endif
1190 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1191 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1192 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1193 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1194 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1195 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1196 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1197 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1198 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1199 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1200 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1201 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1202 						 * enable enforcement for hidden
1203 						 * quota files */
1204 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1205 						  * enforcement for hidden quota
1206 						  * files */
1207 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1208 						  * enforcement */
1209 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1210 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1211 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1212 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
1213 #define EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS 0x4000000
1214 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1215 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1216 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1217 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1218 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1219 
1220 /*
1221  * Mount flags set either automatically (could not be set by mount option)
1222  * based on per file system feature or property or in special cases such as
1223  * distinguishing between explicit mount option definition and default.
1224  */
1225 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1226 						      specified delalloc */
1227 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1228 						      size of blocksize * 8
1229 						      blocks */
1230 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1231 						      file systems */
1232 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1233 						specified journal checksum */
1234 
1235 #define EXT4_MOUNT2_JOURNAL_FAST_COMMIT	0x00000010 /* Journal fast commit */
1236 #define EXT4_MOUNT2_DAX_NEVER		0x00000020 /* Do not allow Direct Access */
1237 #define EXT4_MOUNT2_DAX_INODE		0x00000040 /* For printing options only */
1238 #define EXT4_MOUNT2_MB_OPTIMIZE_SCAN	0x00000080 /* Optimize group
1239 						    * scanning in mballoc
1240 						    */
1241 #define EXT4_MOUNT2_ABORT		0x00000100 /* Abort filesystem */
1242 
1243 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1244 						~EXT4_MOUNT_##opt
1245 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1246 						EXT4_MOUNT_##opt
1247 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1248 					 EXT4_MOUNT_##opt)
1249 
1250 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1251 						~EXT4_MOUNT2_##opt
1252 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1253 						EXT4_MOUNT2_##opt
1254 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1255 					 EXT4_MOUNT2_##opt)
1256 
1257 #define ext4_test_and_set_bit		__test_and_set_bit_le
1258 #define ext4_set_bit			__set_bit_le
1259 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1260 #define ext4_clear_bit			__clear_bit_le
1261 #define ext4_test_bit			test_bit_le
1262 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1263 #define ext4_find_next_bit		find_next_bit_le
1264 
1265 extern void mb_set_bits(void *bm, int cur, int len);
1266 
1267 /*
1268  * Maximal mount counts between two filesystem checks
1269  */
1270 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1271 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1272 
1273 /*
1274  * Behaviour when detecting errors
1275  */
1276 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1277 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1278 #define EXT4_ERRORS_PANIC		3	/* Panic */
1279 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1280 
1281 /* Metadata checksum algorithm codes */
1282 #define EXT4_CRC32C_CHKSUM		1
1283 
1284 #define EXT4_LABEL_MAX			16
1285 
1286 /*
1287  * Structure of the super block
1288  */
1289 struct ext4_super_block {
1290 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1291 	__le32	s_blocks_count_lo;	/* Blocks count */
1292 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1293 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1294 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1295 	__le32	s_first_data_block;	/* First Data Block */
1296 	__le32	s_log_block_size;	/* Block size */
1297 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1298 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1299 	__le32	s_clusters_per_group;	/* # Clusters per group */
1300 	__le32	s_inodes_per_group;	/* # Inodes per group */
1301 	__le32	s_mtime;		/* Mount time */
1302 /*30*/	__le32	s_wtime;		/* Write time */
1303 	__le16	s_mnt_count;		/* Mount count */
1304 	__le16	s_max_mnt_count;	/* Maximal mount count */
1305 	__le16	s_magic;		/* Magic signature */
1306 	__le16	s_state;		/* File system state */
1307 	__le16	s_errors;		/* Behaviour when detecting errors */
1308 	__le16	s_minor_rev_level;	/* minor revision level */
1309 /*40*/	__le32	s_lastcheck;		/* time of last check */
1310 	__le32	s_checkinterval;	/* max. time between checks */
1311 	__le32	s_creator_os;		/* OS */
1312 	__le32	s_rev_level;		/* Revision level */
1313 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1314 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1315 	/*
1316 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1317 	 *
1318 	 * Note: the difference between the compatible feature set and
1319 	 * the incompatible feature set is that if there is a bit set
1320 	 * in the incompatible feature set that the kernel doesn't
1321 	 * know about, it should refuse to mount the filesystem.
1322 	 *
1323 	 * e2fsck's requirements are more strict; if it doesn't know
1324 	 * about a feature in either the compatible or incompatible
1325 	 * feature set, it must abort and not try to meddle with
1326 	 * things it doesn't understand...
1327 	 */
1328 	__le32	s_first_ino;		/* First non-reserved inode */
1329 	__le16  s_inode_size;		/* size of inode structure */
1330 	__le16	s_block_group_nr;	/* block group # of this superblock */
1331 	__le32	s_feature_compat;	/* compatible feature set */
1332 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1333 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1334 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1335 /*78*/	char	s_volume_name[EXT4_LABEL_MAX];	/* volume name */
1336 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
1337 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1338 	/*
1339 	 * Performance hints.  Directory preallocation should only
1340 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1341 	 */
1342 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1343 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1344 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1345 	/*
1346 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1347 	 */
1348 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1349 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1350 	__le32	s_journal_dev;		/* device number of journal file */
1351 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1352 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1353 	__u8	s_def_hash_version;	/* Default hash version to use */
1354 	__u8	s_jnl_backup_type;
1355 	__le16  s_desc_size;		/* size of group descriptor */
1356 /*100*/	__le32	s_default_mount_opts;
1357 	__le32	s_first_meta_bg;	/* First metablock block group */
1358 	__le32	s_mkfs_time;		/* When the filesystem was created */
1359 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1360 	/* 64bit support valid if EXT4_FEATURE_INCOMPAT_64BIT */
1361 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1362 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1363 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1364 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1365 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1366 	__le32	s_flags;		/* Miscellaneous flags */
1367 	__le16  s_raid_stride;		/* RAID stride */
1368 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1369 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1370 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1371 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1372 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1373 	__u8	s_encryption_level;	/* versioning level for encryption */
1374 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1375 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1376 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1377 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1378 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1379 					      snapshot's future use */
1380 	__le32	s_snapshot_list;	/* inode number of the head of the
1381 					   on-disk snapshot list */
1382 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1383 	__le32	s_error_count;		/* number of fs errors */
1384 	__le32	s_first_error_time;	/* first time an error happened */
1385 	__le32	s_first_error_ino;	/* inode involved in first error */
1386 	__le64	s_first_error_block;	/* block involved of first error */
1387 	__u8	s_first_error_func[32] __nonstring;	/* function where the error happened */
1388 	__le32	s_first_error_line;	/* line number where error happened */
1389 	__le32	s_last_error_time;	/* most recent time of an error */
1390 	__le32	s_last_error_ino;	/* inode involved in last error */
1391 	__le32	s_last_error_line;	/* line number where error happened */
1392 	__le64	s_last_error_block;	/* block involved of last error */
1393 	__u8	s_last_error_func[32] __nonstring;	/* function where the error happened */
1394 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1395 	__u8	s_mount_opts[64];
1396 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1397 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1398 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1399 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1400 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1401 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1402 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1403 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1404 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1405 	__u8	s_wtime_hi;
1406 	__u8	s_mtime_hi;
1407 	__u8	s_mkfs_time_hi;
1408 	__u8	s_lastcheck_hi;
1409 	__u8	s_first_error_time_hi;
1410 	__u8	s_last_error_time_hi;
1411 	__u8	s_first_error_errcode;
1412 	__u8    s_last_error_errcode;
1413 	__le16  s_encoding;		/* Filename charset encoding */
1414 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
1415 	__le32  s_orphan_file_inum;	/* Inode for tracking orphan inodes */
1416 	__le32	s_reserved[94];		/* Padding to the end of the block */
1417 	__le32	s_checksum;		/* crc32c(superblock) */
1418 };
1419 
1420 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1421 
1422 #ifdef __KERNEL__
1423 
1424 /* Number of quota types we support */
1425 #define EXT4_MAXQUOTAS 3
1426 
1427 #define EXT4_ENC_UTF8_12_1	1
1428 
1429 /* Types of ext4 journal triggers */
1430 enum ext4_journal_trigger_type {
1431 	EXT4_JTR_ORPHAN_FILE,
1432 	EXT4_JTR_NONE	/* This must be the last entry for indexing to work! */
1433 };
1434 
1435 #define EXT4_JOURNAL_TRIGGER_COUNT EXT4_JTR_NONE
1436 
1437 struct ext4_journal_trigger {
1438 	struct jbd2_buffer_trigger_type tr_triggers;
1439 	struct super_block *sb;
1440 };
1441 
1442 static inline struct ext4_journal_trigger *EXT4_TRIGGER(
1443 				struct jbd2_buffer_trigger_type *trigger)
1444 {
1445 	return container_of(trigger, struct ext4_journal_trigger, tr_triggers);
1446 }
1447 
1448 #define EXT4_ORPHAN_BLOCK_MAGIC 0x0b10ca04
1449 
1450 /* Structure at the tail of orphan block */
1451 struct ext4_orphan_block_tail {
1452 	__le32 ob_magic;
1453 	__le32 ob_checksum;
1454 };
1455 
1456 static inline int ext4_inodes_per_orphan_block(struct super_block *sb)
1457 {
1458 	return (sb->s_blocksize - sizeof(struct ext4_orphan_block_tail)) /
1459 			sizeof(u32);
1460 }
1461 
1462 struct ext4_orphan_block {
1463 	atomic_t ob_free_entries;	/* Number of free orphan entries in block */
1464 	struct buffer_head *ob_bh;	/* Buffer for orphan block */
1465 };
1466 
1467 /*
1468  * Info about orphan file.
1469  */
1470 struct ext4_orphan_info {
1471 	int of_blocks;			/* Number of orphan blocks in a file */
1472 	__u32 of_csum_seed;		/* Checksum seed for orphan file */
1473 	struct ext4_orphan_block *of_binfo;	/* Array with info about orphan
1474 						 * file blocks */
1475 };
1476 
1477 /*
1478  * fourth extended-fs super-block data in memory
1479  */
1480 struct ext4_sb_info {
1481 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1482 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1483 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1484 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1485 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1486 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1487 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1488 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1489 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1490 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1491 	unsigned long s_overhead;  /* # of fs overhead clusters */
1492 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1493 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1494 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1495 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1496 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1497 	struct buffer_head * __rcu *s_group_desc;
1498 	unsigned int s_mount_opt;
1499 	unsigned int s_mount_opt2;
1500 	unsigned long s_mount_flags;
1501 	unsigned int s_def_mount_opt;
1502 	unsigned int s_def_mount_opt2;
1503 	ext4_fsblk_t s_sb_block;
1504 	atomic64_t s_resv_clusters;
1505 	kuid_t s_resuid;
1506 	kgid_t s_resgid;
1507 	unsigned short s_mount_state;
1508 	unsigned short s_pad;
1509 	int s_addr_per_block_bits;
1510 	int s_desc_per_block_bits;
1511 	int s_inode_size;
1512 	int s_first_ino;
1513 	unsigned int s_inode_readahead_blks;
1514 	unsigned int s_inode_goal;
1515 	u32 s_hash_seed[4];
1516 	int s_def_hash_version;
1517 	int s_hash_unsigned;	/* 3 if hash should be unsigned, 0 if not */
1518 	struct percpu_counter s_freeclusters_counter;
1519 	struct percpu_counter s_freeinodes_counter;
1520 	struct percpu_counter s_dirs_counter;
1521 	struct percpu_counter s_dirtyclusters_counter;
1522 	struct percpu_counter s_sra_exceeded_retry_limit;
1523 	struct blockgroup_lock *s_blockgroup_lock;
1524 	struct proc_dir_entry *s_proc;
1525 	struct kobject s_kobj;
1526 	struct completion s_kobj_unregister;
1527 	struct super_block *s_sb;
1528 	struct buffer_head *s_mmp_bh;
1529 
1530 	/* Journaling */
1531 	struct journal_s *s_journal;
1532 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1533 	struct mutex s_orphan_lock;	/* Protects on disk list changes */
1534 	struct list_head s_orphan;	/* List of orphaned inodes in on disk
1535 					   list */
1536 	struct ext4_orphan_info s_orphan_info;
1537 	unsigned long s_commit_interval;
1538 	u32 s_max_batch_time;
1539 	u32 s_min_batch_time;
1540 	struct block_device *s_journal_bdev;
1541 #ifdef CONFIG_QUOTA
1542 	/* Names of quota files with journalled quota */
1543 	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1544 	int s_jquota_fmt;			/* Format of quota to use */
1545 #endif
1546 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1547 	struct ext4_system_blocks __rcu *s_system_blks;
1548 
1549 #ifdef EXTENTS_STATS
1550 	/* ext4 extents stats */
1551 	unsigned long s_ext_min;
1552 	unsigned long s_ext_max;
1553 	unsigned long s_depth_max;
1554 	spinlock_t s_ext_stats_lock;
1555 	unsigned long s_ext_blocks;
1556 	unsigned long s_ext_extents;
1557 #endif
1558 
1559 	/* for buddy allocator */
1560 	struct ext4_group_info ** __rcu *s_group_info;
1561 	struct inode *s_buddy_cache;
1562 	spinlock_t s_md_lock;
1563 	unsigned short *s_mb_offsets;
1564 	unsigned int *s_mb_maxs;
1565 	unsigned int s_group_info_size;
1566 	unsigned int s_mb_free_pending;
1567 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1568 						   after commit completed */
1569 	struct list_head s_discard_list;
1570 	struct work_struct s_discard_work;
1571 	atomic_t s_retry_alloc_pending;
1572 	struct list_head *s_mb_avg_fragment_size;
1573 	rwlock_t *s_mb_avg_fragment_size_locks;
1574 	struct list_head *s_mb_largest_free_orders;
1575 	rwlock_t *s_mb_largest_free_orders_locks;
1576 
1577 	/* tunables */
1578 	unsigned long s_stripe;
1579 	unsigned int s_mb_max_linear_groups;
1580 	unsigned int s_mb_stream_request;
1581 	unsigned int s_mb_max_to_scan;
1582 	unsigned int s_mb_min_to_scan;
1583 	unsigned int s_mb_stats;
1584 	unsigned int s_mb_order2_reqs;
1585 	unsigned int s_mb_group_prealloc;
1586 	unsigned int s_max_dir_size_kb;
1587 	/* where last allocation was done - for stream allocation */
1588 	unsigned long s_mb_last_group;
1589 	unsigned long s_mb_last_start;
1590 	unsigned int s_mb_prefetch;
1591 	unsigned int s_mb_prefetch_limit;
1592 	unsigned int s_mb_best_avail_max_trim_order;
1593 
1594 	/* stats for buddy allocator */
1595 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1596 	atomic_t s_bal_success;	/* we found long enough chunks */
1597 	atomic_t s_bal_allocated;	/* in blocks */
1598 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1599 	atomic_t s_bal_cX_ex_scanned[EXT4_MB_NUM_CRS];	/* total extents scanned */
1600 	atomic_t s_bal_groups_scanned;	/* number of groups scanned */
1601 	atomic_t s_bal_goals;	/* goal hits */
1602 	atomic_t s_bal_len_goals;	/* len goal hits */
1603 	atomic_t s_bal_breaks;	/* too long searches */
1604 	atomic_t s_bal_2orders;	/* 2^order hits */
1605 	atomic_t s_bal_p2_aligned_bad_suggestions;
1606 	atomic_t s_bal_goal_fast_bad_suggestions;
1607 	atomic_t s_bal_best_avail_bad_suggestions;
1608 	atomic64_t s_bal_cX_groups_considered[EXT4_MB_NUM_CRS];
1609 	atomic64_t s_bal_cX_hits[EXT4_MB_NUM_CRS];
1610 	atomic64_t s_bal_cX_failed[EXT4_MB_NUM_CRS];		/* cX loop didn't find blocks */
1611 	atomic_t s_mb_buddies_generated;	/* number of buddies generated */
1612 	atomic64_t s_mb_generation_time;
1613 	atomic_t s_mb_lost_chunks;
1614 	atomic_t s_mb_preallocated;
1615 	atomic_t s_mb_discarded;
1616 	atomic_t s_lock_busy;
1617 
1618 	/* locality groups */
1619 	struct ext4_locality_group __percpu *s_locality_groups;
1620 
1621 	/* for write statistics */
1622 	unsigned long s_sectors_written_start;
1623 	u64 s_kbytes_written;
1624 
1625 	/* the size of zero-out chunk */
1626 	unsigned int s_extent_max_zeroout_kb;
1627 
1628 	unsigned int s_log_groups_per_flex;
1629 	struct flex_groups * __rcu *s_flex_groups;
1630 	ext4_group_t s_flex_groups_allocated;
1631 
1632 	/* workqueue for reserved extent conversions (buffered io) */
1633 	struct workqueue_struct *rsv_conversion_wq;
1634 
1635 	/* timer for periodic error stats printing */
1636 	struct timer_list s_err_report;
1637 
1638 	/* Lazy inode table initialization info */
1639 	struct ext4_li_request *s_li_request;
1640 	/* Wait multiplier for lazy initialization thread */
1641 	unsigned int s_li_wait_mult;
1642 
1643 	/* Kernel thread for multiple mount protection */
1644 	struct task_struct *s_mmp_tsk;
1645 
1646 	/* record the last minlen when FITRIM is called. */
1647 	unsigned long s_last_trim_minblks;
1648 
1649 	/* Reference to checksum algorithm driver via cryptoapi */
1650 	struct crypto_shash *s_chksum_driver;
1651 
1652 	/* Precomputed FS UUID checksum for seeding other checksums */
1653 	__u32 s_csum_seed;
1654 
1655 	/* Reclaim extents from extent status tree */
1656 	struct shrinker s_es_shrinker;
1657 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1658 	long s_es_nr_inode;
1659 	struct ext4_es_stats s_es_stats;
1660 	struct mb_cache *s_ea_block_cache;
1661 	struct mb_cache *s_ea_inode_cache;
1662 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1663 
1664 	/* Journal triggers for checksum computation */
1665 	struct ext4_journal_trigger s_journal_triggers[EXT4_JOURNAL_TRIGGER_COUNT];
1666 
1667 	/* Ratelimit ext4 messages. */
1668 	struct ratelimit_state s_err_ratelimit_state;
1669 	struct ratelimit_state s_warning_ratelimit_state;
1670 	struct ratelimit_state s_msg_ratelimit_state;
1671 	atomic_t s_warning_count;
1672 	atomic_t s_msg_count;
1673 
1674 	/* Encryption policy for '-o test_dummy_encryption' */
1675 	struct fscrypt_dummy_policy s_dummy_enc_policy;
1676 
1677 	/*
1678 	 * Barrier between writepages ops and changing any inode's JOURNAL_DATA
1679 	 * or EXTENTS flag or between writepages ops and changing DELALLOC or
1680 	 * DIOREAD_NOLOCK mount options on remount.
1681 	 */
1682 	struct percpu_rw_semaphore s_writepages_rwsem;
1683 	struct dax_device *s_daxdev;
1684 	u64 s_dax_part_off;
1685 #ifdef CONFIG_EXT4_DEBUG
1686 	unsigned long s_simulate_fail;
1687 #endif
1688 	/* Record the errseq of the backing block device */
1689 	errseq_t s_bdev_wb_err;
1690 	spinlock_t s_bdev_wb_lock;
1691 
1692 	/* Information about errors that happened during this mount */
1693 	spinlock_t s_error_lock;
1694 	int s_add_error_count;
1695 	int s_first_error_code;
1696 	__u32 s_first_error_line;
1697 	__u32 s_first_error_ino;
1698 	__u64 s_first_error_block;
1699 	const char *s_first_error_func;
1700 	time64_t s_first_error_time;
1701 	int s_last_error_code;
1702 	__u32 s_last_error_line;
1703 	__u32 s_last_error_ino;
1704 	__u64 s_last_error_block;
1705 	const char *s_last_error_func;
1706 	time64_t s_last_error_time;
1707 	/*
1708 	 * If we are in a context where we cannot update the on-disk
1709 	 * superblock, we queue the work here.  This is used to update
1710 	 * the error information in the superblock, and for periodic
1711 	 * updates of the superblock called from the commit callback
1712 	 * function.
1713 	 */
1714 	struct work_struct s_sb_upd_work;
1715 
1716 	/* Ext4 fast commit sub transaction ID */
1717 	atomic_t s_fc_subtid;
1718 
1719 	/*
1720 	 * After commit starts, the main queue gets locked, and the further
1721 	 * updates get added in the staging queue.
1722 	 */
1723 #define FC_Q_MAIN	0
1724 #define FC_Q_STAGING	1
1725 	struct list_head s_fc_q[2];	/* Inodes staged for fast commit
1726 					 * that have data changes in them.
1727 					 */
1728 	struct list_head s_fc_dentry_q[2];	/* directory entry updates */
1729 	unsigned int s_fc_bytes;
1730 	/*
1731 	 * Main fast commit lock. This lock protects accesses to the
1732 	 * following fields:
1733 	 * ei->i_fc_list, s_fc_dentry_q, s_fc_q, s_fc_bytes, s_fc_bh.
1734 	 */
1735 	spinlock_t s_fc_lock;
1736 	struct buffer_head *s_fc_bh;
1737 	struct ext4_fc_stats s_fc_stats;
1738 	tid_t s_fc_ineligible_tid;
1739 #ifdef CONFIG_EXT4_DEBUG
1740 	int s_fc_debug_max_replay;
1741 #endif
1742 	struct ext4_fc_replay_state s_fc_replay_state;
1743 };
1744 
1745 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1746 {
1747 	return sb->s_fs_info;
1748 }
1749 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1750 {
1751 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1752 }
1753 
1754 static inline int ext4_writepages_down_read(struct super_block *sb)
1755 {
1756 	percpu_down_read(&EXT4_SB(sb)->s_writepages_rwsem);
1757 	return memalloc_nofs_save();
1758 }
1759 
1760 static inline void ext4_writepages_up_read(struct super_block *sb, int ctx)
1761 {
1762 	memalloc_nofs_restore(ctx);
1763 	percpu_up_read(&EXT4_SB(sb)->s_writepages_rwsem);
1764 }
1765 
1766 static inline int ext4_writepages_down_write(struct super_block *sb)
1767 {
1768 	percpu_down_write(&EXT4_SB(sb)->s_writepages_rwsem);
1769 	return memalloc_nofs_save();
1770 }
1771 
1772 static inline void ext4_writepages_up_write(struct super_block *sb, int ctx)
1773 {
1774 	memalloc_nofs_restore(ctx);
1775 	percpu_up_write(&EXT4_SB(sb)->s_writepages_rwsem);
1776 }
1777 
1778 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1779 {
1780 	return ino == EXT4_ROOT_INO ||
1781 		(ino >= EXT4_FIRST_INO(sb) &&
1782 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1783 }
1784 
1785 /*
1786  * Returns: sbi->field[index]
1787  * Used to access an array element from the following sbi fields which require
1788  * rcu protection to avoid dereferencing an invalid pointer due to reassignment
1789  * - s_group_desc
1790  * - s_group_info
1791  * - s_flex_group
1792  */
1793 #define sbi_array_rcu_deref(sbi, field, index)				   \
1794 ({									   \
1795 	typeof(*((sbi)->field)) _v;					   \
1796 	rcu_read_lock();						   \
1797 	_v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index];	   \
1798 	rcu_read_unlock();						   \
1799 	_v;								   \
1800 })
1801 
1802 /*
1803  * run-time mount flags
1804  */
1805 enum {
1806 	EXT4_MF_MNTDIR_SAMPLED,
1807 	EXT4_MF_FC_INELIGIBLE	/* Fast commit ineligible */
1808 };
1809 
1810 static inline void ext4_set_mount_flag(struct super_block *sb, int bit)
1811 {
1812 	set_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1813 }
1814 
1815 static inline void ext4_clear_mount_flag(struct super_block *sb, int bit)
1816 {
1817 	clear_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1818 }
1819 
1820 static inline int ext4_test_mount_flag(struct super_block *sb, int bit)
1821 {
1822 	return test_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1823 }
1824 
1825 
1826 /*
1827  * Simulate_fail codes
1828  */
1829 #define EXT4_SIM_BBITMAP_EIO	1
1830 #define EXT4_SIM_BBITMAP_CRC	2
1831 #define EXT4_SIM_IBITMAP_EIO	3
1832 #define EXT4_SIM_IBITMAP_CRC	4
1833 #define EXT4_SIM_INODE_EIO	5
1834 #define EXT4_SIM_INODE_CRC	6
1835 #define EXT4_SIM_DIRBLOCK_EIO	7
1836 #define EXT4_SIM_DIRBLOCK_CRC	8
1837 
1838 static inline bool ext4_simulate_fail(struct super_block *sb,
1839 				     unsigned long code)
1840 {
1841 #ifdef CONFIG_EXT4_DEBUG
1842 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1843 
1844 	if (unlikely(sbi->s_simulate_fail == code)) {
1845 		sbi->s_simulate_fail = 0;
1846 		return true;
1847 	}
1848 #endif
1849 	return false;
1850 }
1851 
1852 static inline void ext4_simulate_fail_bh(struct super_block *sb,
1853 					 struct buffer_head *bh,
1854 					 unsigned long code)
1855 {
1856 	if (!IS_ERR(bh) && ext4_simulate_fail(sb, code))
1857 		clear_buffer_uptodate(bh);
1858 }
1859 
1860 /*
1861  * Error number codes for s_{first,last}_error_errno
1862  *
1863  * Linux errno numbers are architecture specific, so we need to translate
1864  * them into something which is architecture independent.   We don't define
1865  * codes for all errno's; just the ones which are most likely to be the cause
1866  * of an ext4_error() call.
1867  */
1868 #define EXT4_ERR_UNKNOWN	 1
1869 #define EXT4_ERR_EIO		 2
1870 #define EXT4_ERR_ENOMEM		 3
1871 #define EXT4_ERR_EFSBADCRC	 4
1872 #define EXT4_ERR_EFSCORRUPTED	 5
1873 #define EXT4_ERR_ENOSPC		 6
1874 #define EXT4_ERR_ENOKEY		 7
1875 #define EXT4_ERR_EROFS		 8
1876 #define EXT4_ERR_EFBIG		 9
1877 #define EXT4_ERR_EEXIST		10
1878 #define EXT4_ERR_ERANGE		11
1879 #define EXT4_ERR_EOVERFLOW	12
1880 #define EXT4_ERR_EBUSY		13
1881 #define EXT4_ERR_ENOTDIR	14
1882 #define EXT4_ERR_ENOTEMPTY	15
1883 #define EXT4_ERR_ESHUTDOWN	16
1884 #define EXT4_ERR_EFAULT		17
1885 
1886 /*
1887  * Inode dynamic state flags
1888  */
1889 enum {
1890 	EXT4_STATE_NEW,			/* inode is newly created */
1891 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1892 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1893 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1894 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1895 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1896 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1897 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1898 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1899 	EXT4_STATE_VERITY_IN_PROGRESS,	/* building fs-verity Merkle tree */
1900 	EXT4_STATE_FC_COMMITTING,	/* Fast commit ongoing */
1901 	EXT4_STATE_ORPHAN_FILE,		/* Inode orphaned in orphan file */
1902 };
1903 
1904 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1905 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1906 {									\
1907 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1908 }									\
1909 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1910 {									\
1911 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1912 }									\
1913 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1914 {									\
1915 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1916 }
1917 
1918 /* Add these declarations here only so that these functions can be
1919  * found by name.  Otherwise, they are very hard to locate. */
1920 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1921 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1922 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1923 EXT4_INODE_BIT_FNS(flag, flags, 0)
1924 
1925 /* Add these declarations here only so that these functions can be
1926  * found by name.  Otherwise, they are very hard to locate. */
1927 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1928 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1929 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1930 #if (BITS_PER_LONG < 64)
1931 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1932 
1933 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1934 {
1935 	(ei)->i_state_flags = 0;
1936 }
1937 #else
1938 EXT4_INODE_BIT_FNS(state, flags, 32)
1939 
1940 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1941 {
1942 	/* We depend on the fact that callers will set i_flags */
1943 }
1944 #endif
1945 #else
1946 /* Assume that user mode programs are passing in an ext4fs superblock, not
1947  * a kernel struct super_block.  This will allow us to call the feature-test
1948  * macros from user land. */
1949 #define EXT4_SB(sb)	(sb)
1950 #endif
1951 
1952 static inline bool ext4_verity_in_progress(struct inode *inode)
1953 {
1954 	return IS_ENABLED(CONFIG_FS_VERITY) &&
1955 	       ext4_test_inode_state(inode, EXT4_STATE_VERITY_IN_PROGRESS);
1956 }
1957 
1958 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1959 
1960 /*
1961  * Codes for operating systems
1962  */
1963 #define EXT4_OS_LINUX		0
1964 #define EXT4_OS_HURD		1
1965 #define EXT4_OS_MASIX		2
1966 #define EXT4_OS_FREEBSD		3
1967 #define EXT4_OS_LITES		4
1968 
1969 /*
1970  * Revision levels
1971  */
1972 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1973 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1974 
1975 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1976 
1977 #define EXT4_GOOD_OLD_INODE_SIZE 128
1978 
1979 #define EXT4_EXTRA_TIMESTAMP_MAX	(((s64)1 << 34) - 1  + S32_MIN)
1980 #define EXT4_NON_EXTRA_TIMESTAMP_MAX	S32_MAX
1981 #define EXT4_TIMESTAMP_MIN		S32_MIN
1982 
1983 /*
1984  * Feature set definitions
1985  */
1986 
1987 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1988 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1989 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1990 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1991 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1992 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1993 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1994 /*
1995  * The reason why "FAST_COMMIT" is a compat feature is that, FS becomes
1996  * incompatible only if fast commit blocks are present in the FS. Since we
1997  * clear the journal (and thus the fast commit blocks), we don't mark FS as
1998  * incompatible. We also have a JBD2 incompat feature, which gets set when
1999  * there are fast commit blocks present in the journal.
2000  */
2001 #define EXT4_FEATURE_COMPAT_FAST_COMMIT		0x0400
2002 #define EXT4_FEATURE_COMPAT_STABLE_INODES	0x0800
2003 #define EXT4_FEATURE_COMPAT_ORPHAN_FILE		0x1000	/* Orphan file exists */
2004 
2005 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
2006 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
2007 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
2008 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
2009 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
2010 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
2011 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
2012 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
2013 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
2014 /*
2015  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
2016  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
2017  * all other data structures' checksums.  However, the METADATA_CSUM and
2018  * GDT_CSUM bits are mutually exclusive.
2019  */
2020 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
2021 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
2022 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
2023 #define EXT4_FEATURE_RO_COMPAT_VERITY		0x8000
2024 #define EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT	0x10000 /* Orphan file may be
2025 							   non-empty */
2026 
2027 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
2028 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
2029 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
2030 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
2031 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
2032 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
2033 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
2034 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
2035 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
2036 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
2037 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
2038 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
2039 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
2040 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
2041 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
2042 #define EXT4_FEATURE_INCOMPAT_CASEFOLD		0x20000
2043 
2044 extern void ext4_update_dynamic_rev(struct super_block *sb);
2045 
2046 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
2047 static inline bool ext4_has_feature_##name(struct super_block *sb) \
2048 { \
2049 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
2050 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
2051 } \
2052 static inline void ext4_set_feature_##name(struct super_block *sb) \
2053 { \
2054 	ext4_update_dynamic_rev(sb); \
2055 	EXT4_SB(sb)->s_es->s_feature_compat |= \
2056 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
2057 } \
2058 static inline void ext4_clear_feature_##name(struct super_block *sb) \
2059 { \
2060 	EXT4_SB(sb)->s_es->s_feature_compat &= \
2061 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
2062 }
2063 
2064 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
2065 static inline bool ext4_has_feature_##name(struct super_block *sb) \
2066 { \
2067 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2068 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
2069 } \
2070 static inline void ext4_set_feature_##name(struct super_block *sb) \
2071 { \
2072 	ext4_update_dynamic_rev(sb); \
2073 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
2074 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
2075 } \
2076 static inline void ext4_clear_feature_##name(struct super_block *sb) \
2077 { \
2078 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
2079 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
2080 }
2081 
2082 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
2083 static inline bool ext4_has_feature_##name(struct super_block *sb) \
2084 { \
2085 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2086 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
2087 } \
2088 static inline void ext4_set_feature_##name(struct super_block *sb) \
2089 { \
2090 	ext4_update_dynamic_rev(sb); \
2091 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
2092 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2093 } \
2094 static inline void ext4_clear_feature_##name(struct super_block *sb) \
2095 { \
2096 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
2097 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2098 }
2099 
2100 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
2101 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
2102 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
2103 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
2104 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
2105 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
2106 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
2107 EXT4_FEATURE_COMPAT_FUNCS(fast_commit,		FAST_COMMIT)
2108 EXT4_FEATURE_COMPAT_FUNCS(stable_inodes,	STABLE_INODES)
2109 EXT4_FEATURE_COMPAT_FUNCS(orphan_file,		ORPHAN_FILE)
2110 
2111 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
2112 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
2113 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
2114 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
2115 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
2116 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
2117 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
2118 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
2119 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
2120 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
2121 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
2122 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
2123 EXT4_FEATURE_RO_COMPAT_FUNCS(verity,		VERITY)
2124 EXT4_FEATURE_RO_COMPAT_FUNCS(orphan_present,	ORPHAN_PRESENT)
2125 
2126 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
2127 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
2128 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
2129 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
2130 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
2131 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
2132 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
2133 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
2134 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
2135 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
2136 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
2137 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
2138 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
2139 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
2140 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
2141 EXT4_FEATURE_INCOMPAT_FUNCS(casefold,		CASEFOLD)
2142 
2143 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2144 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2145 					 EXT4_FEATURE_INCOMPAT_META_BG)
2146 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2147 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2148 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2149 
2150 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2151 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2152 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
2153 					 EXT4_FEATURE_INCOMPAT_META_BG)
2154 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2155 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2156 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2157 
2158 #define EXT4_FEATURE_COMPAT_SUPP	(EXT4_FEATURE_COMPAT_EXT_ATTR| \
2159 					 EXT4_FEATURE_COMPAT_ORPHAN_FILE)
2160 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2161 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
2162 					 EXT4_FEATURE_INCOMPAT_META_BG| \
2163 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
2164 					 EXT4_FEATURE_INCOMPAT_64BIT| \
2165 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
2166 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
2167 					 EXT4_FEATURE_INCOMPAT_MMP | \
2168 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
2169 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
2170 					 EXT4_FEATURE_INCOMPAT_CASEFOLD | \
2171 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
2172 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
2173 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2174 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2175 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
2176 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
2177 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
2178 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
2179 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
2180 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
2181 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
2182 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
2183 					 EXT4_FEATURE_RO_COMPAT_PROJECT |\
2184 					 EXT4_FEATURE_RO_COMPAT_VERITY |\
2185 					 EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT)
2186 
2187 #define EXTN_FEATURE_FUNCS(ver) \
2188 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
2189 { \
2190 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
2191 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
2192 } \
2193 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
2194 { \
2195 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2196 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
2197 } \
2198 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
2199 { \
2200 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2201 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
2202 }
2203 
2204 EXTN_FEATURE_FUNCS(2)
2205 EXTN_FEATURE_FUNCS(3)
2206 EXTN_FEATURE_FUNCS(4)
2207 
2208 static inline bool ext4_has_compat_features(struct super_block *sb)
2209 {
2210 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
2211 }
2212 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
2213 {
2214 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
2215 }
2216 static inline bool ext4_has_incompat_features(struct super_block *sb)
2217 {
2218 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
2219 }
2220 
2221 extern int ext4_feature_set_ok(struct super_block *sb, int readonly);
2222 
2223 /*
2224  * Superblock flags
2225  */
2226 #define EXT4_FLAGS_RESIZING	0
2227 #define EXT4_FLAGS_SHUTDOWN	1
2228 #define EXT4_FLAGS_BDEV_IS_DAX	2
2229 
2230 static inline int ext4_forced_shutdown(struct super_block *sb)
2231 {
2232 	return test_bit(EXT4_FLAGS_SHUTDOWN, &EXT4_SB(sb)->s_ext4_flags);
2233 }
2234 
2235 /*
2236  * Default values for user and/or group using reserved blocks
2237  */
2238 #define	EXT4_DEF_RESUID		0
2239 #define	EXT4_DEF_RESGID		0
2240 
2241 /*
2242  * Default project ID
2243  */
2244 #define	EXT4_DEF_PROJID		0
2245 
2246 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
2247 
2248 /*
2249  * Default mount options
2250  */
2251 #define EXT4_DEFM_DEBUG		0x0001
2252 #define EXT4_DEFM_BSDGROUPS	0x0002
2253 #define EXT4_DEFM_XATTR_USER	0x0004
2254 #define EXT4_DEFM_ACL		0x0008
2255 #define EXT4_DEFM_UID16		0x0010
2256 #define EXT4_DEFM_JMODE		0x0060
2257 #define EXT4_DEFM_JMODE_DATA	0x0020
2258 #define EXT4_DEFM_JMODE_ORDERED	0x0040
2259 #define EXT4_DEFM_JMODE_WBACK	0x0060
2260 #define EXT4_DEFM_NOBARRIER	0x0100
2261 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
2262 #define EXT4_DEFM_DISCARD	0x0400
2263 #define EXT4_DEFM_NODELALLOC	0x0800
2264 
2265 /*
2266  * Default journal batch times
2267  */
2268 #define EXT4_DEF_MIN_BATCH_TIME	0
2269 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
2270 
2271 /*
2272  * Minimum number of groups in a flexgroup before we separate out
2273  * directories into the first block group of a flexgroup
2274  */
2275 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
2276 
2277 /*
2278  * Structure of a directory entry
2279  */
2280 #define EXT4_NAME_LEN 255
2281 /*
2282  * Base length of the ext4 directory entry excluding the name length
2283  */
2284 #define EXT4_BASE_DIR_LEN (sizeof(struct ext4_dir_entry_2) - EXT4_NAME_LEN)
2285 
2286 struct ext4_dir_entry {
2287 	__le32	inode;			/* Inode number */
2288 	__le16	rec_len;		/* Directory entry length */
2289 	__le16	name_len;		/* Name length */
2290 	char	name[EXT4_NAME_LEN];	/* File name */
2291 };
2292 
2293 
2294 /*
2295  * Encrypted Casefolded entries require saving the hash on disk. This structure
2296  * followed ext4_dir_entry_2's name[name_len] at the next 4 byte aligned
2297  * boundary.
2298  */
2299 struct ext4_dir_entry_hash {
2300 	__le32 hash;
2301 	__le32 minor_hash;
2302 };
2303 
2304 /*
2305  * The new version of the directory entry.  Since EXT4 structures are
2306  * stored in intel byte order, and the name_len field could never be
2307  * bigger than 255 chars, it's safe to reclaim the extra byte for the
2308  * file_type field.
2309  */
2310 struct ext4_dir_entry_2 {
2311 	__le32	inode;			/* Inode number */
2312 	__le16	rec_len;		/* Directory entry length */
2313 	__u8	name_len;		/* Name length */
2314 	__u8	file_type;		/* See file type macros EXT4_FT_* below */
2315 	char	name[EXT4_NAME_LEN];	/* File name */
2316 };
2317 
2318 /*
2319  * Access the hashes at the end of ext4_dir_entry_2
2320  */
2321 #define EXT4_DIRENT_HASHES(entry) \
2322 	((struct ext4_dir_entry_hash *) \
2323 		(((void *)(entry)) + \
2324 		((8 + (entry)->name_len + EXT4_DIR_ROUND) & ~EXT4_DIR_ROUND)))
2325 #define EXT4_DIRENT_HASH(entry) le32_to_cpu(EXT4_DIRENT_HASHES(de)->hash)
2326 #define EXT4_DIRENT_MINOR_HASH(entry) \
2327 		le32_to_cpu(EXT4_DIRENT_HASHES(de)->minor_hash)
2328 
2329 static inline bool ext4_hash_in_dirent(const struct inode *inode)
2330 {
2331 	return IS_CASEFOLDED(inode) && IS_ENCRYPTED(inode);
2332 }
2333 
2334 /*
2335  * This is a bogus directory entry at the end of each leaf block that
2336  * records checksums.
2337  */
2338 struct ext4_dir_entry_tail {
2339 	__le32	det_reserved_zero1;	/* Pretend to be unused */
2340 	__le16	det_rec_len;		/* 12 */
2341 	__u8	det_reserved_zero2;	/* Zero name length */
2342 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
2343 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
2344 };
2345 
2346 #define EXT4_DIRENT_TAIL(block, blocksize) \
2347 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
2348 					((blocksize) - \
2349 					 sizeof(struct ext4_dir_entry_tail))))
2350 
2351 /*
2352  * Ext4 directory file types.  Only the low 3 bits are used.  The
2353  * other bits are reserved for now.
2354  */
2355 #define EXT4_FT_UNKNOWN		0
2356 #define EXT4_FT_REG_FILE	1
2357 #define EXT4_FT_DIR		2
2358 #define EXT4_FT_CHRDEV		3
2359 #define EXT4_FT_BLKDEV		4
2360 #define EXT4_FT_FIFO		5
2361 #define EXT4_FT_SOCK		6
2362 #define EXT4_FT_SYMLINK		7
2363 
2364 #define EXT4_FT_MAX		8
2365 
2366 #define EXT4_FT_DIR_CSUM	0xDE
2367 
2368 /*
2369  * EXT4_DIR_PAD defines the directory entries boundaries
2370  *
2371  * NOTE: It must be a multiple of 4
2372  */
2373 #define EXT4_DIR_PAD			4
2374 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
2375 #define EXT4_MAX_REC_LEN		((1<<16)-1)
2376 
2377 /*
2378  * The rec_len is dependent on the type of directory. Directories that are
2379  * casefolded and encrypted need to store the hash as well, so we add room for
2380  * ext4_extended_dir_entry_2. For all entries related to '.' or '..' you should
2381  * pass NULL for dir, as those entries do not use the extra fields.
2382  */
2383 static inline unsigned int ext4_dir_rec_len(__u8 name_len,
2384 						const struct inode *dir)
2385 {
2386 	int rec_len = (name_len + 8 + EXT4_DIR_ROUND);
2387 
2388 	if (dir && ext4_hash_in_dirent(dir))
2389 		rec_len += sizeof(struct ext4_dir_entry_hash);
2390 	return (rec_len & ~EXT4_DIR_ROUND);
2391 }
2392 
2393 /*
2394  * If we ever get support for fs block sizes > page_size, we'll need
2395  * to remove the #if statements in the next two functions...
2396  */
2397 static inline unsigned int
2398 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
2399 {
2400 	unsigned len = le16_to_cpu(dlen);
2401 
2402 #if (PAGE_SIZE >= 65536)
2403 	if (len == EXT4_MAX_REC_LEN || len == 0)
2404 		return blocksize;
2405 	return (len & 65532) | ((len & 3) << 16);
2406 #else
2407 	return len;
2408 #endif
2409 }
2410 
2411 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2412 {
2413 	BUG_ON((len > blocksize) || (blocksize > (1 << 18)) || (len & 3));
2414 #if (PAGE_SIZE >= 65536)
2415 	if (len < 65536)
2416 		return cpu_to_le16(len);
2417 	if (len == blocksize) {
2418 		if (blocksize == 65536)
2419 			return cpu_to_le16(EXT4_MAX_REC_LEN);
2420 		else
2421 			return cpu_to_le16(0);
2422 	}
2423 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2424 #else
2425 	return cpu_to_le16(len);
2426 #endif
2427 }
2428 
2429 /*
2430  * Hash Tree Directory indexing
2431  * (c) Daniel Phillips, 2001
2432  */
2433 
2434 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2435 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2436 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2437 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2438 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2439 
2440 /* Legal values for the dx_root hash_version field: */
2441 
2442 #define DX_HASH_LEGACY			0
2443 #define DX_HASH_HALF_MD4		1
2444 #define DX_HASH_TEA			2
2445 #define DX_HASH_LEGACY_UNSIGNED		3
2446 #define DX_HASH_HALF_MD4_UNSIGNED	4
2447 #define DX_HASH_TEA_UNSIGNED		5
2448 #define DX_HASH_SIPHASH			6
2449 
2450 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2451 			      const void *address, unsigned int length)
2452 {
2453 	struct {
2454 		struct shash_desc shash;
2455 		char ctx[4];
2456 	} desc;
2457 
2458 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2459 
2460 	desc.shash.tfm = sbi->s_chksum_driver;
2461 	*(u32 *)desc.ctx = crc;
2462 
2463 	BUG_ON(crypto_shash_update(&desc.shash, address, length));
2464 
2465 	return *(u32 *)desc.ctx;
2466 }
2467 
2468 #ifdef __KERNEL__
2469 
2470 /* hash info structure used by the directory hash */
2471 struct dx_hash_info
2472 {
2473 	u32		hash;
2474 	u32		minor_hash;
2475 	int		hash_version;
2476 	u32		*seed;
2477 };
2478 
2479 
2480 /* 32 and 64 bit signed EOF for dx directories */
2481 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2482 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2483 
2484 
2485 /*
2486  * Control parameters used by ext4_htree_next_block
2487  */
2488 #define HASH_NB_ALWAYS		1
2489 
2490 struct ext4_filename {
2491 	const struct qstr *usr_fname;
2492 	struct fscrypt_str disk_name;
2493 	struct dx_hash_info hinfo;
2494 #ifdef CONFIG_FS_ENCRYPTION
2495 	struct fscrypt_str crypto_buf;
2496 #endif
2497 #if IS_ENABLED(CONFIG_UNICODE)
2498 	struct fscrypt_str cf_name;
2499 #endif
2500 };
2501 
2502 #define fname_name(p) ((p)->disk_name.name)
2503 #define fname_usr_name(p) ((p)->usr_fname->name)
2504 #define fname_len(p)  ((p)->disk_name.len)
2505 
2506 /*
2507  * Describe an inode's exact location on disk and in memory
2508  */
2509 struct ext4_iloc
2510 {
2511 	struct buffer_head *bh;
2512 	unsigned long offset;
2513 	ext4_group_t block_group;
2514 };
2515 
2516 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2517 {
2518 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2519 }
2520 
2521 static inline bool ext4_is_quota_file(struct inode *inode)
2522 {
2523 	return IS_NOQUOTA(inode) &&
2524 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2525 }
2526 
2527 /*
2528  * This structure is stuffed into the struct file's private_data field
2529  * for directories.  It is where we put information so that we can do
2530  * readdir operations in hash tree order.
2531  */
2532 struct dir_private_info {
2533 	struct rb_root	root;
2534 	struct rb_node	*curr_node;
2535 	struct fname	*extra_fname;
2536 	loff_t		last_pos;
2537 	__u32		curr_hash;
2538 	__u32		curr_minor_hash;
2539 	__u32		next_hash;
2540 };
2541 
2542 /* calculate the first block number of the group */
2543 static inline ext4_fsblk_t
2544 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2545 {
2546 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2547 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2548 }
2549 
2550 /*
2551  * Special error return code only used by dx_probe() and its callers.
2552  */
2553 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2554 
2555 /* htree levels for ext4 */
2556 #define	EXT4_HTREE_LEVEL_COMPAT	2
2557 #define	EXT4_HTREE_LEVEL	3
2558 
2559 static inline int ext4_dir_htree_level(struct super_block *sb)
2560 {
2561 	return ext4_has_feature_largedir(sb) ?
2562 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2563 }
2564 
2565 /*
2566  * Timeout and state flag for lazy initialization inode thread.
2567  */
2568 #define EXT4_DEF_LI_WAIT_MULT			10
2569 #define EXT4_DEF_LI_MAX_START_DELAY		5
2570 #define EXT4_LAZYINIT_QUIT			0x0001
2571 #define EXT4_LAZYINIT_RUNNING			0x0002
2572 
2573 /*
2574  * Lazy inode table initialization info
2575  */
2576 struct ext4_lazy_init {
2577 	unsigned long		li_state;
2578 	struct list_head	li_request_list;
2579 	struct mutex		li_list_mtx;
2580 };
2581 
2582 enum ext4_li_mode {
2583 	EXT4_LI_MODE_PREFETCH_BBITMAP,
2584 	EXT4_LI_MODE_ITABLE,
2585 };
2586 
2587 struct ext4_li_request {
2588 	struct super_block	*lr_super;
2589 	enum ext4_li_mode	lr_mode;
2590 	ext4_group_t		lr_first_not_zeroed;
2591 	ext4_group_t		lr_next_group;
2592 	struct list_head	lr_request;
2593 	unsigned long		lr_next_sched;
2594 	unsigned long		lr_timeout;
2595 };
2596 
2597 struct ext4_features {
2598 	struct kobject f_kobj;
2599 	struct completion f_kobj_unregister;
2600 };
2601 
2602 /*
2603  * This structure will be used for multiple mount protection. It will be
2604  * written into the block number saved in the s_mmp_block field in the
2605  * superblock. Programs that check MMP should assume that if
2606  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2607  * to use the filesystem, regardless of how old the timestamp is.
2608  */
2609 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2610 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2611 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2612 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2613 
2614 struct mmp_struct {
2615 	__le32	mmp_magic;		/* Magic number for MMP */
2616 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2617 
2618 	/*
2619 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2620 	 * purposes and do not affect the correctness of the algorithm
2621 	 */
2622 	__le64	mmp_time;		/* Time last updated */
2623 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2624 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2625 
2626 	/*
2627 	 * mmp_check_interval is used to verify if the MMP block has been
2628 	 * updated on the block device. The value is updated based on the
2629 	 * maximum time to write the MMP block during an update cycle.
2630 	 */
2631 	__le16	mmp_check_interval;
2632 
2633 	__le16	mmp_pad1;
2634 	__le32	mmp_pad2[226];
2635 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2636 };
2637 
2638 /* arguments passed to the mmp thread */
2639 struct mmpd_data {
2640 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2641 	struct super_block *sb;  /* super block of the fs */
2642 };
2643 
2644 /*
2645  * Check interval multiplier
2646  * The MMP block is written every update interval and initially checked every
2647  * update interval x the multiplier (the value is then adapted based on the
2648  * write latency). The reason is that writes can be delayed under load and we
2649  * don't want readers to incorrectly assume that the filesystem is no longer
2650  * in use.
2651  */
2652 #define EXT4_MMP_CHECK_MULT		2UL
2653 
2654 /*
2655  * Minimum interval for MMP checking in seconds.
2656  */
2657 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2658 
2659 /*
2660  * Maximum interval for MMP checking in seconds.
2661  */
2662 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2663 
2664 /*
2665  * Function prototypes
2666  */
2667 
2668 /*
2669  * Ok, these declarations are also in <linux/kernel.h> but none of the
2670  * ext4 source programs needs to include it so they are duplicated here.
2671  */
2672 # define NORET_TYPE	/**/
2673 # define ATTRIB_NORET	__attribute__((noreturn))
2674 # define NORET_AND	noreturn,
2675 
2676 /* bitmap.c */
2677 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2678 void ext4_inode_bitmap_csum_set(struct super_block *sb,
2679 				struct ext4_group_desc *gdp,
2680 				struct buffer_head *bh, int sz);
2681 int ext4_inode_bitmap_csum_verify(struct super_block *sb,
2682 				  struct ext4_group_desc *gdp,
2683 				  struct buffer_head *bh, int sz);
2684 void ext4_block_bitmap_csum_set(struct super_block *sb,
2685 				struct ext4_group_desc *gdp,
2686 				struct buffer_head *bh);
2687 int ext4_block_bitmap_csum_verify(struct super_block *sb,
2688 				  struct ext4_group_desc *gdp,
2689 				  struct buffer_head *bh);
2690 
2691 /* balloc.c */
2692 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2693 					 ext4_fsblk_t blocknr,
2694 					 ext4_group_t *blockgrpp,
2695 					 ext4_grpblk_t *offsetp);
2696 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2697 					  ext4_fsblk_t block);
2698 
2699 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2700 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2701 			ext4_group_t group);
2702 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2703 					 ext4_fsblk_t goal,
2704 					 unsigned int flags,
2705 					 unsigned long *count,
2706 					 int *errp);
2707 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2708 				    s64 nclusters, unsigned int flags);
2709 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2710 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2711 						    ext4_group_t block_group,
2712 						    struct buffer_head ** bh);
2713 extern struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2714 						   ext4_group_t group);
2715 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2716 
2717 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2718 						ext4_group_t block_group,
2719 						bool ignore_locked);
2720 extern int ext4_wait_block_bitmap(struct super_block *sb,
2721 				  ext4_group_t block_group,
2722 				  struct buffer_head *bh);
2723 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2724 						  ext4_group_t block_group);
2725 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2726 					      ext4_group_t block_group,
2727 					      struct ext4_group_desc *gdp);
2728 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2729 
2730 #if IS_ENABLED(CONFIG_UNICODE)
2731 extern int ext4_fname_setup_ci_filename(struct inode *dir,
2732 					 const struct qstr *iname,
2733 					 struct ext4_filename *fname);
2734 #endif
2735 
2736 /* ext4 encryption related stuff goes here crypto.c */
2737 #ifdef CONFIG_FS_ENCRYPTION
2738 extern const struct fscrypt_operations ext4_cryptops;
2739 
2740 int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
2741 			      int lookup, struct ext4_filename *fname);
2742 
2743 int ext4_fname_prepare_lookup(struct inode *dir, struct dentry *dentry,
2744 			      struct ext4_filename *fname);
2745 
2746 void ext4_fname_free_filename(struct ext4_filename *fname);
2747 
2748 int ext4_ioctl_get_encryption_pwsalt(struct file *filp, void __user *arg);
2749 
2750 #else /* !CONFIG_FS_ENCRYPTION */
2751 static inline int ext4_fname_setup_filename(struct inode *dir,
2752 					    const struct qstr *iname,
2753 					    int lookup,
2754 					    struct ext4_filename *fname)
2755 {
2756 	int err = 0;
2757 	fname->usr_fname = iname;
2758 	fname->disk_name.name = (unsigned char *) iname->name;
2759 	fname->disk_name.len = iname->len;
2760 
2761 #if IS_ENABLED(CONFIG_UNICODE)
2762 	err = ext4_fname_setup_ci_filename(dir, iname, fname);
2763 #endif
2764 
2765 	return err;
2766 }
2767 
2768 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2769 					    struct dentry *dentry,
2770 					    struct ext4_filename *fname)
2771 {
2772 	return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
2773 }
2774 
2775 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2776 {
2777 #if IS_ENABLED(CONFIG_UNICODE)
2778 	kfree(fname->cf_name.name);
2779 	fname->cf_name.name = NULL;
2780 #endif
2781 }
2782 
2783 static inline int ext4_ioctl_get_encryption_pwsalt(struct file *filp,
2784 						   void __user *arg)
2785 {
2786 	return -EOPNOTSUPP;
2787 }
2788 #endif /* !CONFIG_FS_ENCRYPTION */
2789 
2790 /* dir.c */
2791 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2792 				  struct file *,
2793 				  struct ext4_dir_entry_2 *,
2794 				  struct buffer_head *, char *, int,
2795 				  unsigned int);
2796 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset) \
2797 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2798 				(de), (bh), (buf), (size), (offset)))
2799 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2800 				__u32 minor_hash,
2801 				struct ext4_dir_entry_2 *dirent,
2802 				struct fscrypt_str *ent_name);
2803 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2804 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2805 			     struct buffer_head *bh,
2806 			     void *buf, int buf_size,
2807 			     struct ext4_filename *fname,
2808 			     struct ext4_dir_entry_2 **dest_de);
2809 void ext4_insert_dentry(struct inode *dir, struct inode *inode,
2810 			struct ext4_dir_entry_2 *de,
2811 			int buf_size,
2812 			struct ext4_filename *fname);
2813 static inline void ext4_update_dx_flag(struct inode *inode)
2814 {
2815 	if (!ext4_has_feature_dir_index(inode->i_sb) &&
2816 	    ext4_test_inode_flag(inode, EXT4_INODE_INDEX)) {
2817 		/* ext4_iget() should have caught this... */
2818 		WARN_ON_ONCE(ext4_has_feature_metadata_csum(inode->i_sb));
2819 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2820 	}
2821 }
2822 static const unsigned char ext4_filetype_table[] = {
2823 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2824 };
2825 
2826 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2827 {
2828 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2829 		return DT_UNKNOWN;
2830 
2831 	return ext4_filetype_table[filetype];
2832 }
2833 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2834 			     void *buf, int buf_size);
2835 
2836 /* fsync.c */
2837 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2838 
2839 /* hash.c */
2840 extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
2841 			  struct dx_hash_info *hinfo);
2842 
2843 /* ialloc.c */
2844 extern int ext4_mark_inode_used(struct super_block *sb, int ino);
2845 extern struct inode *__ext4_new_inode(struct mnt_idmap *, handle_t *,
2846 				      struct inode *, umode_t,
2847 				      const struct qstr *qstr, __u32 goal,
2848 				      uid_t *owner, __u32 i_flags,
2849 				      int handle_type, unsigned int line_no,
2850 				      int nblocks);
2851 
2852 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags)          \
2853 	__ext4_new_inode(&nop_mnt_idmap, (handle), (dir), (mode), (qstr),      \
2854 			 (goal), (owner), i_flags, 0, 0, 0)
2855 #define ext4_new_inode_start_handle(idmap, dir, mode, qstr, goal, owner, \
2856 				    type, nblocks)		    \
2857 	__ext4_new_inode((idmap), NULL, (dir), (mode), (qstr), (goal), (owner), \
2858 			 0, (type), __LINE__, (nblocks))
2859 
2860 
2861 extern void ext4_free_inode(handle_t *, struct inode *);
2862 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2863 extern unsigned long ext4_count_free_inodes(struct super_block *);
2864 extern unsigned long ext4_count_dirs(struct super_block *);
2865 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2866 extern int ext4_init_inode_table(struct super_block *sb,
2867 				 ext4_group_t group, int barrier);
2868 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2869 
2870 /* fast_commit.c */
2871 int ext4_fc_info_show(struct seq_file *seq, void *v);
2872 void ext4_fc_init(struct super_block *sb, journal_t *journal);
2873 void ext4_fc_init_inode(struct inode *inode);
2874 void ext4_fc_track_range(handle_t *handle, struct inode *inode, ext4_lblk_t start,
2875 			 ext4_lblk_t end);
2876 void __ext4_fc_track_unlink(handle_t *handle, struct inode *inode,
2877 	struct dentry *dentry);
2878 void __ext4_fc_track_link(handle_t *handle, struct inode *inode,
2879 	struct dentry *dentry);
2880 void ext4_fc_track_unlink(handle_t *handle, struct dentry *dentry);
2881 void ext4_fc_track_link(handle_t *handle, struct dentry *dentry);
2882 void __ext4_fc_track_create(handle_t *handle, struct inode *inode,
2883 			    struct dentry *dentry);
2884 void ext4_fc_track_create(handle_t *handle, struct dentry *dentry);
2885 void ext4_fc_track_inode(handle_t *handle, struct inode *inode);
2886 void ext4_fc_mark_ineligible(struct super_block *sb, int reason, handle_t *handle);
2887 void ext4_fc_start_update(struct inode *inode);
2888 void ext4_fc_stop_update(struct inode *inode);
2889 void ext4_fc_del(struct inode *inode);
2890 bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block);
2891 void ext4_fc_replay_cleanup(struct super_block *sb);
2892 int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
2893 int __init ext4_fc_init_dentry_cache(void);
2894 void ext4_fc_destroy_dentry_cache(void);
2895 int ext4_fc_record_regions(struct super_block *sb, int ino,
2896 			   ext4_lblk_t lblk, ext4_fsblk_t pblk,
2897 			   int len, int replay);
2898 
2899 /* mballoc.c */
2900 extern const struct seq_operations ext4_mb_seq_groups_ops;
2901 extern const struct seq_operations ext4_mb_seq_structs_summary_ops;
2902 extern int ext4_seq_mb_stats_show(struct seq_file *seq, void *offset);
2903 extern int ext4_mb_init(struct super_block *);
2904 extern int ext4_mb_release(struct super_block *);
2905 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2906 				struct ext4_allocation_request *, int *);
2907 extern void ext4_discard_preallocations(struct inode *, unsigned int);
2908 extern int __init ext4_init_mballoc(void);
2909 extern void ext4_exit_mballoc(void);
2910 extern ext4_group_t ext4_mb_prefetch(struct super_block *sb,
2911 				     ext4_group_t group,
2912 				     unsigned int nr, int *cnt);
2913 extern void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group,
2914 				  unsigned int nr);
2915 
2916 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2917 			     struct buffer_head *bh, ext4_fsblk_t block,
2918 			     unsigned long count, int flags);
2919 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2920 				   ext4_group_t ngroups);
2921 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2922 		ext4_group_t i, struct ext4_group_desc *desc);
2923 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2924 				ext4_fsblk_t block, unsigned long count);
2925 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2926 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2927 extern void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block,
2928 		       int len, int state);
2929 static inline bool ext4_mb_cr_expensive(enum criteria cr)
2930 {
2931 	return cr >= CR_GOAL_LEN_SLOW;
2932 }
2933 
2934 /* inode.c */
2935 void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
2936 			 struct ext4_inode_info *ei);
2937 int ext4_inode_is_fast_symlink(struct inode *inode);
2938 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2939 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2940 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2941 		     bool wait, struct buffer_head **bhs);
2942 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2943 			     struct buffer_head *bh_result, int create);
2944 int ext4_get_block(struct inode *inode, sector_t iblock,
2945 		   struct buffer_head *bh_result, int create);
2946 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2947 			   struct buffer_head *bh, int create);
2948 int ext4_walk_page_buffers(handle_t *handle,
2949 			   struct inode *inode,
2950 			   struct buffer_head *head,
2951 			   unsigned from,
2952 			   unsigned to,
2953 			   int *partial,
2954 			   int (*fn)(handle_t *handle, struct inode *inode,
2955 				     struct buffer_head *bh));
2956 int do_journal_get_write_access(handle_t *handle, struct inode *inode,
2957 				struct buffer_head *bh);
2958 #define FALL_BACK_TO_NONDELALLOC 1
2959 #define CONVERT_INLINE_DATA	 2
2960 
2961 typedef enum {
2962 	EXT4_IGET_NORMAL =	0,
2963 	EXT4_IGET_SPECIAL =	0x0001, /* OK to iget a system inode */
2964 	EXT4_IGET_HANDLE = 	0x0002,	/* Inode # is from a handle */
2965 	EXT4_IGET_BAD =		0x0004, /* Allow to iget a bad inode */
2966 	EXT4_IGET_EA_INODE =	0x0008	/* Inode should contain an EA value */
2967 } ext4_iget_flags;
2968 
2969 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2970 				 ext4_iget_flags flags, const char *function,
2971 				 unsigned int line);
2972 
2973 #define ext4_iget(sb, ino, flags) \
2974 	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2975 
2976 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2977 extern int  ext4_setattr(struct mnt_idmap *, struct dentry *,
2978 			 struct iattr *);
2979 extern u32  ext4_dio_alignment(struct inode *inode);
2980 extern int  ext4_getattr(struct mnt_idmap *, const struct path *,
2981 			 struct kstat *, u32, unsigned int);
2982 extern void ext4_evict_inode(struct inode *);
2983 extern void ext4_clear_inode(struct inode *);
2984 extern int  ext4_file_getattr(struct mnt_idmap *, const struct path *,
2985 			      struct kstat *, u32, unsigned int);
2986 extern void ext4_dirty_inode(struct inode *, int);
2987 extern int ext4_change_inode_journal_flag(struct inode *, int);
2988 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2989 extern int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino,
2990 			  struct ext4_iloc *iloc);
2991 extern int ext4_inode_attach_jinode(struct inode *inode);
2992 extern int ext4_can_truncate(struct inode *inode);
2993 extern int ext4_truncate(struct inode *);
2994 extern int ext4_break_layouts(struct inode *);
2995 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
2996 extern void ext4_set_inode_flags(struct inode *, bool init);
2997 extern int ext4_alloc_da_blocks(struct inode *inode);
2998 extern void ext4_set_aops(struct inode *inode);
2999 extern int ext4_writepage_trans_blocks(struct inode *);
3000 extern int ext4_normal_submit_inode_data_buffers(struct jbd2_inode *jinode);
3001 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
3002 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
3003 			     loff_t lstart, loff_t lend);
3004 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
3005 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
3006 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
3007 extern void ext4_da_release_space(struct inode *inode, int to_free);
3008 extern void ext4_da_update_reserve_space(struct inode *inode,
3009 					int used, int quota_claim);
3010 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
3011 			      ext4_fsblk_t pblk, ext4_lblk_t len);
3012 
3013 /* indirect.c */
3014 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
3015 				struct ext4_map_blocks *map, int flags);
3016 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
3017 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
3018 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
3019 				 ext4_lblk_t start, ext4_lblk_t end);
3020 
3021 /* ioctl.c */
3022 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
3023 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
3024 int ext4_fileattr_set(struct mnt_idmap *idmap,
3025 		      struct dentry *dentry, struct fileattr *fa);
3026 int ext4_fileattr_get(struct dentry *dentry, struct fileattr *fa);
3027 extern void ext4_reset_inode_seed(struct inode *inode);
3028 int ext4_update_overhead(struct super_block *sb, bool force);
3029 int ext4_force_shutdown(struct super_block *sb, u32 flags);
3030 
3031 /* migrate.c */
3032 extern int ext4_ext_migrate(struct inode *);
3033 extern int ext4_ind_migrate(struct inode *inode);
3034 
3035 /* namei.c */
3036 extern int ext4_init_new_dir(handle_t *handle, struct inode *dir,
3037 			     struct inode *inode);
3038 extern int ext4_dirblock_csum_verify(struct inode *inode,
3039 				     struct buffer_head *bh);
3040 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
3041 				__u32 start_minor_hash, __u32 *next_hash);
3042 extern int ext4_search_dir(struct buffer_head *bh,
3043 			   char *search_buf,
3044 			   int buf_size,
3045 			   struct inode *dir,
3046 			   struct ext4_filename *fname,
3047 			   unsigned int offset,
3048 			   struct ext4_dir_entry_2 **res_dir);
3049 extern int ext4_generic_delete_entry(struct inode *dir,
3050 				     struct ext4_dir_entry_2 *de_del,
3051 				     struct buffer_head *bh,
3052 				     void *entry_buf,
3053 				     int buf_size,
3054 				     int csum_size);
3055 extern bool ext4_empty_dir(struct inode *inode);
3056 
3057 /* resize.c */
3058 extern void ext4_kvfree_array_rcu(void *to_free);
3059 extern int ext4_group_add(struct super_block *sb,
3060 				struct ext4_new_group_data *input);
3061 extern int ext4_group_extend(struct super_block *sb,
3062 				struct ext4_super_block *es,
3063 				ext4_fsblk_t n_blocks_count);
3064 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
3065 extern unsigned int ext4_list_backups(struct super_block *sb,
3066 				      unsigned int *three, unsigned int *five,
3067 				      unsigned int *seven);
3068 
3069 /* super.c */
3070 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
3071 					 sector_t block, blk_opf_t op_flags);
3072 extern struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
3073 						   sector_t block);
3074 extern void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
3075 				bh_end_io_t *end_io);
3076 extern int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
3077 			bh_end_io_t *end_io);
3078 extern int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait);
3079 extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
3080 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
3081 extern int ext4_calculate_overhead(struct super_block *sb);
3082 extern __le32 ext4_superblock_csum(struct super_block *sb,
3083 				   struct ext4_super_block *es);
3084 extern void ext4_superblock_csum_set(struct super_block *sb);
3085 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
3086 				    ext4_group_t ngroup);
3087 extern const char *ext4_decode_error(struct super_block *sb, int errno,
3088 				     char nbuf[16]);
3089 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
3090 					     ext4_group_t block_group,
3091 					     unsigned int flags);
3092 extern unsigned int ext4_num_base_meta_blocks(struct super_block *sb,
3093 					      ext4_group_t block_group);
3094 
3095 extern __printf(7, 8)
3096 void __ext4_error(struct super_block *, const char *, unsigned int, bool,
3097 		  int, __u64, const char *, ...);
3098 extern __printf(6, 7)
3099 void __ext4_error_inode(struct inode *, const char *, unsigned int,
3100 			ext4_fsblk_t, int, const char *, ...);
3101 extern __printf(5, 6)
3102 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
3103 		     const char *, ...);
3104 extern void __ext4_std_error(struct super_block *, const char *,
3105 			     unsigned int, int);
3106 extern __printf(4, 5)
3107 void __ext4_warning(struct super_block *, const char *, unsigned int,
3108 		    const char *, ...);
3109 extern __printf(4, 5)
3110 void __ext4_warning_inode(const struct inode *inode, const char *function,
3111 			  unsigned int line, const char *fmt, ...);
3112 extern __printf(3, 4)
3113 void __ext4_msg(struct super_block *, const char *, const char *, ...);
3114 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
3115 			   const char *, unsigned int, const char *);
3116 extern __printf(7, 8)
3117 void __ext4_grp_locked_error(const char *, unsigned int,
3118 			     struct super_block *, ext4_group_t,
3119 			     unsigned long, ext4_fsblk_t,
3120 			     const char *, ...);
3121 
3122 #define EXT4_ERROR_INODE(inode, fmt, a...) \
3123 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
3124 
3125 #define EXT4_ERROR_INODE_ERR(inode, err, fmt, a...)			\
3126 	__ext4_error_inode((inode), __func__, __LINE__, 0, (err), (fmt), ## a)
3127 
3128 #define ext4_error_inode_block(inode, block, err, fmt, a...)		\
3129 	__ext4_error_inode((inode), __func__, __LINE__, (block), (err),	\
3130 			   (fmt), ## a)
3131 
3132 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
3133 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
3134 
3135 #define ext4_abort(sb, err, fmt, a...)					\
3136 	__ext4_error((sb), __func__, __LINE__, true, (err), 0, (fmt), ## a)
3137 
3138 #ifdef CONFIG_PRINTK
3139 
3140 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
3141 	__ext4_error_inode(inode, func, line, block, 0, fmt, ##__VA_ARGS__)
3142 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
3143 	__ext4_error_inode((inode), (func), (line), (block), 		\
3144 			   (err), (fmt), ##__VA_ARGS__)
3145 #define ext4_error_file(file, func, line, block, fmt, ...)		\
3146 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
3147 #define ext4_error(sb, fmt, ...)					\
3148 	__ext4_error((sb), __func__, __LINE__, false, 0, 0, (fmt),	\
3149 		##__VA_ARGS__)
3150 #define ext4_error_err(sb, err, fmt, ...)				\
3151 	__ext4_error((sb), __func__, __LINE__, false, (err), 0, (fmt),	\
3152 		##__VA_ARGS__)
3153 #define ext4_warning(sb, fmt, ...)					\
3154 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
3155 #define ext4_warning_inode(inode, fmt, ...)				\
3156 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
3157 #define ext4_msg(sb, level, fmt, ...)				\
3158 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
3159 #define dump_mmp_msg(sb, mmp, msg)					\
3160 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
3161 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
3162 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
3163 				fmt, ##__VA_ARGS__)
3164 
3165 #else
3166 
3167 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
3168 do {									\
3169 	no_printk(fmt, ##__VA_ARGS__);					\
3170 	__ext4_error_inode(inode, "", 0, block, 0, " ");		\
3171 } while (0)
3172 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
3173 do {									\
3174 	no_printk(fmt, ##__VA_ARGS__);					\
3175 	__ext4_error_inode(inode, "", 0, block, err, " ");		\
3176 } while (0)
3177 #define ext4_error_file(file, func, line, block, fmt, ...)		\
3178 do {									\
3179 	no_printk(fmt, ##__VA_ARGS__);					\
3180 	__ext4_error_file(file, "", 0, block, " ");			\
3181 } while (0)
3182 #define ext4_error(sb, fmt, ...)					\
3183 do {									\
3184 	no_printk(fmt, ##__VA_ARGS__);					\
3185 	__ext4_error(sb, "", 0, false, 0, 0, " ");			\
3186 } while (0)
3187 #define ext4_error_err(sb, err, fmt, ...)				\
3188 do {									\
3189 	no_printk(fmt, ##__VA_ARGS__);					\
3190 	__ext4_error(sb, "", 0, false, err, 0, " ");			\
3191 } while (0)
3192 #define ext4_warning(sb, fmt, ...)					\
3193 do {									\
3194 	no_printk(fmt, ##__VA_ARGS__);					\
3195 	__ext4_warning(sb, "", 0, " ");					\
3196 } while (0)
3197 #define ext4_warning_inode(inode, fmt, ...)				\
3198 do {									\
3199 	no_printk(fmt, ##__VA_ARGS__);					\
3200 	__ext4_warning_inode(inode, "", 0, " ");			\
3201 } while (0)
3202 #define ext4_msg(sb, level, fmt, ...)					\
3203 do {									\
3204 	no_printk(fmt, ##__VA_ARGS__);					\
3205 	__ext4_msg(sb, "", " ");					\
3206 } while (0)
3207 #define dump_mmp_msg(sb, mmp, msg)					\
3208 	__dump_mmp_msg(sb, mmp, "", 0, "")
3209 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
3210 do {									\
3211 	no_printk(fmt, ##__VA_ARGS__);				\
3212 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
3213 } while (0)
3214 
3215 #endif
3216 
3217 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
3218 				      struct ext4_group_desc *bg);
3219 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
3220 				      struct ext4_group_desc *bg);
3221 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
3222 				     struct ext4_group_desc *bg);
3223 extern __u32 ext4_free_group_clusters(struct super_block *sb,
3224 				      struct ext4_group_desc *bg);
3225 extern __u32 ext4_free_inodes_count(struct super_block *sb,
3226 				 struct ext4_group_desc *bg);
3227 extern __u32 ext4_used_dirs_count(struct super_block *sb,
3228 				struct ext4_group_desc *bg);
3229 extern __u32 ext4_itable_unused_count(struct super_block *sb,
3230 				   struct ext4_group_desc *bg);
3231 extern void ext4_block_bitmap_set(struct super_block *sb,
3232 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3233 extern void ext4_inode_bitmap_set(struct super_block *sb,
3234 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3235 extern void ext4_inode_table_set(struct super_block *sb,
3236 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
3237 extern void ext4_free_group_clusters_set(struct super_block *sb,
3238 					 struct ext4_group_desc *bg,
3239 					 __u32 count);
3240 extern void ext4_free_inodes_set(struct super_block *sb,
3241 				struct ext4_group_desc *bg, __u32 count);
3242 extern void ext4_used_dirs_set(struct super_block *sb,
3243 				struct ext4_group_desc *bg, __u32 count);
3244 extern void ext4_itable_unused_set(struct super_block *sb,
3245 				   struct ext4_group_desc *bg, __u32 count);
3246 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
3247 				       struct ext4_group_desc *gdp);
3248 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
3249 				     struct ext4_group_desc *gdp);
3250 extern int ext4_register_li_request(struct super_block *sb,
3251 				    ext4_group_t first_not_zeroed);
3252 
3253 static inline int ext4_has_metadata_csum(struct super_block *sb)
3254 {
3255 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
3256 		     !EXT4_SB(sb)->s_chksum_driver);
3257 
3258 	return ext4_has_feature_metadata_csum(sb) &&
3259 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
3260 }
3261 
3262 static inline int ext4_has_group_desc_csum(struct super_block *sb)
3263 {
3264 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
3265 }
3266 
3267 #define ext4_read_incompat_64bit_val(es, name) \
3268 	(((es)->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT) \
3269 		? (ext4_fsblk_t)le32_to_cpu(es->name##_hi) << 32 : 0) | \
3270 		le32_to_cpu(es->name##_lo))
3271 
3272 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
3273 {
3274 	return ext4_read_incompat_64bit_val(es, s_blocks_count);
3275 }
3276 
3277 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
3278 {
3279 	return ext4_read_incompat_64bit_val(es, s_r_blocks_count);
3280 }
3281 
3282 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
3283 {
3284 	return ext4_read_incompat_64bit_val(es, s_free_blocks_count);
3285 }
3286 
3287 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
3288 					 ext4_fsblk_t blk)
3289 {
3290 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
3291 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
3292 }
3293 
3294 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
3295 					      ext4_fsblk_t blk)
3296 {
3297 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
3298 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
3299 }
3300 
3301 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
3302 					   ext4_fsblk_t blk)
3303 {
3304 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
3305 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
3306 }
3307 
3308 static inline loff_t ext4_isize(struct super_block *sb,
3309 				struct ext4_inode *raw_inode)
3310 {
3311 	if (ext4_has_feature_largedir(sb) ||
3312 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
3313 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
3314 			le32_to_cpu(raw_inode->i_size_lo);
3315 
3316 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
3317 }
3318 
3319 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
3320 {
3321 	raw_inode->i_size_lo = cpu_to_le32(i_size);
3322 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
3323 }
3324 
3325 /*
3326  * Reading s_groups_count requires using smp_rmb() afterwards.  See
3327  * the locking protocol documented in the comments of ext4_group_add()
3328  * in resize.c
3329  */
3330 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
3331 {
3332 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
3333 
3334 	smp_rmb();
3335 	return ngroups;
3336 }
3337 
3338 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
3339 					     ext4_group_t block_group)
3340 {
3341 	return block_group >> sbi->s_log_groups_per_flex;
3342 }
3343 
3344 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
3345 {
3346 	return 1 << sbi->s_log_groups_per_flex;
3347 }
3348 
3349 #define ext4_std_error(sb, errno)				\
3350 do {								\
3351 	if ((errno))						\
3352 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
3353 } while (0)
3354 
3355 #ifdef CONFIG_SMP
3356 /* Each CPU can accumulate percpu_counter_batch clusters in their local
3357  * counters. So we need to make sure we have free clusters more
3358  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
3359  */
3360 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
3361 #else
3362 #define EXT4_FREECLUSTERS_WATERMARK 0
3363 #endif
3364 
3365 /* Update i_disksize. Requires i_rwsem to avoid races with truncate */
3366 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
3367 {
3368 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
3369 		     !inode_is_locked(inode));
3370 	down_write(&EXT4_I(inode)->i_data_sem);
3371 	if (newsize > EXT4_I(inode)->i_disksize)
3372 		WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
3373 	up_write(&EXT4_I(inode)->i_data_sem);
3374 }
3375 
3376 /* Update i_size, i_disksize. Requires i_rwsem to avoid races with truncate */
3377 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
3378 {
3379 	int changed = 0;
3380 
3381 	if (newsize > inode->i_size) {
3382 		i_size_write(inode, newsize);
3383 		changed = 1;
3384 	}
3385 	if (newsize > EXT4_I(inode)->i_disksize) {
3386 		ext4_update_i_disksize(inode, newsize);
3387 		changed |= 2;
3388 	}
3389 	return changed;
3390 }
3391 
3392 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
3393 				      loff_t len);
3394 
3395 struct ext4_group_info {
3396 	unsigned long   bb_state;
3397 #ifdef AGGRESSIVE_CHECK
3398 	unsigned long	bb_check_counter;
3399 #endif
3400 	struct rb_root  bb_free_root;
3401 	ext4_grpblk_t	bb_first_free;	/* first free block */
3402 	ext4_grpblk_t	bb_free;	/* total free blocks */
3403 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
3404 	int		bb_avg_fragment_size_order;	/* order of average
3405 							   fragment in BG */
3406 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
3407 	ext4_group_t	bb_group;	/* Group number */
3408 	struct          list_head bb_prealloc_list;
3409 #ifdef DOUBLE_CHECK
3410 	void            *bb_bitmap;
3411 #endif
3412 	struct rw_semaphore alloc_sem;
3413 	struct list_head bb_avg_fragment_size_node;
3414 	struct list_head bb_largest_free_order_node;
3415 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
3416 					 * regions, index is order.
3417 					 * bb_counters[3] = 5 means
3418 					 * 5 free 8-block regions. */
3419 };
3420 
3421 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
3422 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
3423 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
3424 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
3425 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT		\
3426 	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
3427 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT		\
3428 	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
3429 #define EXT4_GROUP_INFO_BBITMAP_READ_BIT	4
3430 
3431 #define EXT4_MB_GRP_NEED_INIT(grp)	\
3432 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
3433 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
3434 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3435 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
3436 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3437 
3438 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
3439 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3440 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
3441 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3442 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
3443 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3444 #define EXT4_MB_GRP_TEST_AND_SET_READ(grp)	\
3445 	(test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_READ_BIT, &((grp)->bb_state)))
3446 
3447 #define EXT4_MAX_CONTENTION		8
3448 #define EXT4_CONTENTION_THRESHOLD	2
3449 
3450 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
3451 					      ext4_group_t group)
3452 {
3453 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
3454 }
3455 
3456 /*
3457  * Returns true if the filesystem is busy enough that attempts to
3458  * access the block group locks has run into contention.
3459  */
3460 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
3461 {
3462 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
3463 }
3464 
3465 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
3466 {
3467 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
3468 	if (spin_trylock(lock))
3469 		/*
3470 		 * We're able to grab the lock right away, so drop the
3471 		 * lock contention counter.
3472 		 */
3473 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
3474 	else {
3475 		/*
3476 		 * The lock is busy, so bump the contention counter,
3477 		 * and then wait on the spin lock.
3478 		 */
3479 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
3480 				  EXT4_MAX_CONTENTION);
3481 		spin_lock(lock);
3482 	}
3483 }
3484 
3485 static inline void ext4_unlock_group(struct super_block *sb,
3486 					ext4_group_t group)
3487 {
3488 	spin_unlock(ext4_group_lock_ptr(sb, group));
3489 }
3490 
3491 #ifdef CONFIG_QUOTA
3492 static inline bool ext4_quota_capable(struct super_block *sb)
3493 {
3494 	return (test_opt(sb, QUOTA) || ext4_has_feature_quota(sb));
3495 }
3496 
3497 static inline bool ext4_is_quota_journalled(struct super_block *sb)
3498 {
3499 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3500 
3501 	return (ext4_has_feature_quota(sb) ||
3502 		sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]);
3503 }
3504 int ext4_enable_quotas(struct super_block *sb);
3505 #endif
3506 
3507 /*
3508  * Block validity checking
3509  */
3510 #define ext4_check_indirect_blockref(inode, bh)				\
3511 	ext4_check_blockref(__func__, __LINE__, inode,			\
3512 			    (__le32 *)(bh)->b_data,			\
3513 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3514 
3515 #define ext4_ind_check_inode(inode)					\
3516 	ext4_check_blockref(__func__, __LINE__, inode,			\
3517 			    EXT4_I(inode)->i_data,			\
3518 			    EXT4_NDIR_BLOCKS)
3519 
3520 /*
3521  * Inodes and files operations
3522  */
3523 
3524 /* dir.c */
3525 extern const struct file_operations ext4_dir_operations;
3526 
3527 /* file.c */
3528 extern const struct inode_operations ext4_file_inode_operations;
3529 extern const struct file_operations ext4_file_operations;
3530 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
3531 
3532 /* inline.c */
3533 extern int ext4_get_max_inline_size(struct inode *inode);
3534 extern int ext4_find_inline_data_nolock(struct inode *inode);
3535 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3536 
3537 int ext4_readpage_inline(struct inode *inode, struct folio *folio);
3538 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3539 					 struct inode *inode,
3540 					 loff_t pos, unsigned len,
3541 					 struct page **pagep);
3542 int ext4_write_inline_data_end(struct inode *inode, loff_t pos, unsigned len,
3543 			       unsigned copied, struct folio *folio);
3544 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3545 					   struct inode *inode,
3546 					   loff_t pos, unsigned len,
3547 					   struct page **pagep,
3548 					   void **fsdata);
3549 extern int ext4_try_add_inline_entry(handle_t *handle,
3550 				     struct ext4_filename *fname,
3551 				     struct inode *dir, struct inode *inode);
3552 extern int ext4_try_create_inline_dir(handle_t *handle,
3553 				      struct inode *parent,
3554 				      struct inode *inode);
3555 extern int ext4_read_inline_dir(struct file *filp,
3556 				struct dir_context *ctx,
3557 				int *has_inline_data);
3558 extern int ext4_inlinedir_to_tree(struct file *dir_file,
3559 				  struct inode *dir, ext4_lblk_t block,
3560 				  struct dx_hash_info *hinfo,
3561 				  __u32 start_hash, __u32 start_minor_hash,
3562 				  int *has_inline_data);
3563 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3564 					struct ext4_filename *fname,
3565 					struct ext4_dir_entry_2 **res_dir,
3566 					int *has_inline_data);
3567 extern int ext4_delete_inline_entry(handle_t *handle,
3568 				    struct inode *dir,
3569 				    struct ext4_dir_entry_2 *de_del,
3570 				    struct buffer_head *bh,
3571 				    int *has_inline_data);
3572 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3573 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3574 					struct ext4_dir_entry_2 **parent_de,
3575 					int *retval);
3576 extern void *ext4_read_inline_link(struct inode *inode);
3577 
3578 struct iomap;
3579 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3580 
3581 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3582 
3583 extern int ext4_convert_inline_data(struct inode *inode);
3584 
3585 static inline int ext4_has_inline_data(struct inode *inode)
3586 {
3587 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3588 	       EXT4_I(inode)->i_inline_off;
3589 }
3590 
3591 /* namei.c */
3592 extern const struct inode_operations ext4_dir_inode_operations;
3593 extern const struct inode_operations ext4_special_inode_operations;
3594 extern struct dentry *ext4_get_parent(struct dentry *child);
3595 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3596 				 struct ext4_dir_entry_2 *de,
3597 				 int blocksize, int csum_size,
3598 				 unsigned int parent_ino, int dotdot_real_len);
3599 extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
3600 					unsigned int blocksize);
3601 extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
3602 				      struct buffer_head *bh);
3603 extern int __ext4_unlink(struct inode *dir, const struct qstr *d_name,
3604 			 struct inode *inode, struct dentry *dentry);
3605 extern int __ext4_link(struct inode *dir, struct inode *inode,
3606 		       struct dentry *dentry);
3607 
3608 #define S_SHIFT 12
3609 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3610 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3611 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3612 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3613 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3614 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3615 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3616 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3617 };
3618 
3619 static inline void ext4_set_de_type(struct super_block *sb,
3620 				struct ext4_dir_entry_2 *de,
3621 				umode_t mode) {
3622 	if (ext4_has_feature_filetype(sb))
3623 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3624 }
3625 
3626 /* readpages.c */
3627 extern int ext4_mpage_readpages(struct inode *inode,
3628 		struct readahead_control *rac, struct folio *folio);
3629 extern int __init ext4_init_post_read_processing(void);
3630 extern void ext4_exit_post_read_processing(void);
3631 
3632 /* symlink.c */
3633 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3634 extern const struct inode_operations ext4_symlink_inode_operations;
3635 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3636 
3637 /* sysfs.c */
3638 extern void ext4_notify_error_sysfs(struct ext4_sb_info *sbi);
3639 extern int ext4_register_sysfs(struct super_block *sb);
3640 extern void ext4_unregister_sysfs(struct super_block *sb);
3641 extern int __init ext4_init_sysfs(void);
3642 extern void ext4_exit_sysfs(void);
3643 
3644 /* block_validity */
3645 extern void ext4_release_system_zone(struct super_block *sb);
3646 extern int ext4_setup_system_zone(struct super_block *sb);
3647 extern int __init ext4_init_system_zone(void);
3648 extern void ext4_exit_system_zone(void);
3649 extern int ext4_inode_block_valid(struct inode *inode,
3650 				  ext4_fsblk_t start_blk,
3651 				  unsigned int count);
3652 extern int ext4_check_blockref(const char *, unsigned int,
3653 			       struct inode *, __le32 *, unsigned int);
3654 extern int ext4_sb_block_valid(struct super_block *sb, struct inode *inode,
3655 				ext4_fsblk_t start_blk, unsigned int count);
3656 
3657 
3658 /* extents.c */
3659 struct ext4_ext_path;
3660 struct ext4_extent;
3661 
3662 /*
3663  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3664  * __le32.
3665  */
3666 #define EXT_MAX_BLOCKS	0xffffffff
3667 
3668 extern void ext4_ext_tree_init(handle_t *handle, struct inode *inode);
3669 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3670 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3671 			       struct ext4_map_blocks *map, int flags);
3672 extern int ext4_ext_truncate(handle_t *, struct inode *);
3673 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3674 				 ext4_lblk_t end);
3675 extern void ext4_ext_init(struct super_block *);
3676 extern void ext4_ext_release(struct super_block *);
3677 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3678 			  loff_t len);
3679 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3680 					  loff_t offset, ssize_t len);
3681 extern int ext4_convert_unwritten_io_end_vec(handle_t *handle,
3682 					     ext4_io_end_t *io_end);
3683 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3684 			   struct ext4_map_blocks *map, int flags);
3685 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3686 						   int num,
3687 						   struct ext4_ext_path *path);
3688 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3689 				  struct ext4_ext_path **,
3690 				  struct ext4_extent *, int);
3691 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3692 					      struct ext4_ext_path **,
3693 					      int flags);
3694 extern void ext4_free_ext_path(struct ext4_ext_path *);
3695 extern int ext4_ext_check_inode(struct inode *inode);
3696 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3697 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3698 			__u64 start, __u64 len);
3699 extern int ext4_get_es_cache(struct inode *inode,
3700 			     struct fiemap_extent_info *fieinfo,
3701 			     __u64 start, __u64 len);
3702 extern int ext4_ext_precache(struct inode *inode);
3703 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3704 				struct inode *inode2, ext4_lblk_t lblk1,
3705 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3706 			     int mark_unwritten,int *err);
3707 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3708 extern int ext4_datasem_ensure_credits(handle_t *handle, struct inode *inode,
3709 				       int check_cred, int restart_cred,
3710 				       int revoke_cred);
3711 extern void ext4_ext_replay_shrink_inode(struct inode *inode, ext4_lblk_t end);
3712 extern int ext4_ext_replay_set_iblocks(struct inode *inode);
3713 extern int ext4_ext_replay_update_ex(struct inode *inode, ext4_lblk_t start,
3714 		int len, int unwritten, ext4_fsblk_t pblk);
3715 extern int ext4_ext_clear_bb(struct inode *inode);
3716 
3717 
3718 /* move_extent.c */
3719 extern void ext4_double_down_write_data_sem(struct inode *first,
3720 					    struct inode *second);
3721 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3722 					  struct inode *donor_inode);
3723 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3724 			     __u64 start_orig, __u64 start_donor,
3725 			     __u64 len, __u64 *moved_len);
3726 
3727 /* page-io.c */
3728 extern int __init ext4_init_pageio(void);
3729 extern void ext4_exit_pageio(void);
3730 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3731 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3732 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3733 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3734 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3735 				struct writeback_control *wbc);
3736 extern void ext4_end_io_rsv_work(struct work_struct *work);
3737 extern void ext4_io_submit(struct ext4_io_submit *io);
3738 int ext4_bio_write_folio(struct ext4_io_submit *io, struct folio *page,
3739 		size_t len);
3740 extern struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end);
3741 extern struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end);
3742 
3743 /* mmp.c */
3744 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3745 
3746 /* mmp.c */
3747 extern void ext4_stop_mmpd(struct ext4_sb_info *sbi);
3748 
3749 /* verity.c */
3750 extern const struct fsverity_operations ext4_verityops;
3751 
3752 /* orphan.c */
3753 extern int ext4_orphan_add(handle_t *, struct inode *);
3754 extern int ext4_orphan_del(handle_t *, struct inode *);
3755 extern void ext4_orphan_cleanup(struct super_block *sb,
3756 				struct ext4_super_block *es);
3757 extern void ext4_release_orphan_info(struct super_block *sb);
3758 extern int ext4_init_orphan_info(struct super_block *sb);
3759 extern int ext4_orphan_file_empty(struct super_block *sb);
3760 extern void ext4_orphan_file_block_trigger(
3761 				struct jbd2_buffer_trigger_type *triggers,
3762 				struct buffer_head *bh,
3763 				void *data, size_t size);
3764 
3765 /*
3766  * Add new method to test whether block and inode bitmaps are properly
3767  * initialized. With uninit_bg reading the block from disk is not enough
3768  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3769  */
3770 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3771 
3772 static inline int bitmap_uptodate(struct buffer_head *bh)
3773 {
3774 	return (buffer_uptodate(bh) &&
3775 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3776 }
3777 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3778 {
3779 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3780 }
3781 
3782 /* For ioend & aio unwritten conversion wait queues */
3783 #define EXT4_WQ_HASH_SZ		37
3784 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3785 					    EXT4_WQ_HASH_SZ])
3786 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3787 
3788 extern int ext4_resize_begin(struct super_block *sb);
3789 extern int ext4_resize_end(struct super_block *sb, bool update_backups);
3790 
3791 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3792 					      struct ext4_io_end *io_end)
3793 {
3794 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3795 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3796 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3797 	}
3798 }
3799 
3800 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3801 {
3802 	struct inode *inode = io_end->inode;
3803 
3804 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3805 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3806 		/* Wake up anyone waiting on unwritten extent conversion */
3807 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3808 			wake_up_all(ext4_ioend_wq(inode));
3809 	}
3810 }
3811 
3812 extern const struct iomap_ops ext4_iomap_ops;
3813 extern const struct iomap_ops ext4_iomap_overwrite_ops;
3814 extern const struct iomap_ops ext4_iomap_report_ops;
3815 
3816 static inline int ext4_buffer_uptodate(struct buffer_head *bh)
3817 {
3818 	/*
3819 	 * If the buffer has the write error flag, we have failed
3820 	 * to write out data in the block.  In this  case, we don't
3821 	 * have to read the block because we may read the old data
3822 	 * successfully.
3823 	 */
3824 	if (buffer_write_io_error(bh))
3825 		set_buffer_uptodate(bh);
3826 	return buffer_uptodate(bh);
3827 }
3828 
3829 #endif	/* __KERNEL__ */
3830 
3831 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3832 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3833 
3834 #endif	/* _EXT4_H */
3835