xref: /openbmc/linux/fs/ext4/ext4.h (revision 95298d63)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  ext4.h
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/include/linux/minix_fs.h
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  */
16 
17 #ifndef _EXT4_H
18 #define _EXT4_H
19 
20 #include <linux/types.h>
21 #include <linux/blkdev.h>
22 #include <linux/magic.h>
23 #include <linux/jbd2.h>
24 #include <linux/quota.h>
25 #include <linux/rwsem.h>
26 #include <linux/rbtree.h>
27 #include <linux/seqlock.h>
28 #include <linux/mutex.h>
29 #include <linux/timer.h>
30 #include <linux/version.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 
44 #include <linux/fscrypt.h>
45 #include <linux/fsverity.h>
46 
47 #include <linux/compiler.h>
48 
49 /*
50  * The fourth extended filesystem constants/structures
51  */
52 
53 /*
54  * with AGGRESSIVE_CHECK allocator runs consistency checks over
55  * structures. these checks slow things down a lot
56  */
57 #define AGGRESSIVE_CHECK__
58 
59 /*
60  * with DOUBLE_CHECK defined mballoc creates persistent in-core
61  * bitmaps, maintains and uses them to check for double allocations
62  */
63 #define DOUBLE_CHECK__
64 
65 /*
66  * Define EXT4FS_DEBUG to produce debug messages
67  */
68 #undef EXT4FS_DEBUG
69 
70 /*
71  * Debug code
72  */
73 #ifdef EXT4FS_DEBUG
74 #define ext4_debug(f, a...)						\
75 	do {								\
76 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
77 			__FILE__, __LINE__, __func__);			\
78 		printk(KERN_DEBUG f, ## a);				\
79 	} while (0)
80 #else
81 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
82 #endif
83 
84  /*
85   * Turn on EXT_DEBUG to enable ext4_ext_show_path/leaf/move in extents.c
86   */
87 #define EXT_DEBUG__
88 
89 /*
90  * Dynamic printk for controlled extents debugging.
91  */
92 #ifdef CONFIG_EXT4_DEBUG
93 #define ext_debug(ino, fmt, ...)					\
94 	pr_debug("[%s/%d] EXT4-fs (%s): ino %lu: (%s, %d): %s:" fmt,	\
95 		 current->comm, task_pid_nr(current),			\
96 		 ino->i_sb->s_id, ino->i_ino, __FILE__, __LINE__,	\
97 		 __func__, ##__VA_ARGS__)
98 #else
99 #define ext_debug(ino, fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
100 #endif
101 
102 /* data type for block offset of block group */
103 typedef int ext4_grpblk_t;
104 
105 /* data type for filesystem-wide blocks number */
106 typedef unsigned long long ext4_fsblk_t;
107 
108 /* data type for file logical block number */
109 typedef __u32 ext4_lblk_t;
110 
111 /* data type for block group number */
112 typedef unsigned int ext4_group_t;
113 
114 enum SHIFT_DIRECTION {
115 	SHIFT_LEFT = 0,
116 	SHIFT_RIGHT,
117 };
118 
119 /*
120  * Flags used in mballoc's allocation_context flags field.
121  *
122  * Also used to show what's going on for debugging purposes when the
123  * flag field is exported via the traceport interface
124  */
125 
126 /* prefer goal again. length */
127 #define EXT4_MB_HINT_MERGE		0x0001
128 /* blocks already reserved */
129 #define EXT4_MB_HINT_RESERVED		0x0002
130 /* metadata is being allocated */
131 #define EXT4_MB_HINT_METADATA		0x0004
132 /* first blocks in the file */
133 #define EXT4_MB_HINT_FIRST		0x0008
134 /* search for the best chunk */
135 #define EXT4_MB_HINT_BEST		0x0010
136 /* data is being allocated */
137 #define EXT4_MB_HINT_DATA		0x0020
138 /* don't preallocate (for tails) */
139 #define EXT4_MB_HINT_NOPREALLOC		0x0040
140 /* allocate for locality group */
141 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
142 /* allocate goal blocks or none */
143 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
144 /* goal is meaningful */
145 #define EXT4_MB_HINT_TRY_GOAL		0x0200
146 /* blocks already pre-reserved by delayed allocation */
147 #define EXT4_MB_DELALLOC_RESERVED	0x0400
148 /* We are doing stream allocation */
149 #define EXT4_MB_STREAM_ALLOC		0x0800
150 /* Use reserved root blocks if needed */
151 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
152 /* Use blocks from reserved pool */
153 #define EXT4_MB_USE_RESERVED		0x2000
154 /* Do strict check for free blocks while retrying block allocation */
155 #define EXT4_MB_STRICT_CHECK		0x4000
156 
157 struct ext4_allocation_request {
158 	/* target inode for block we're allocating */
159 	struct inode *inode;
160 	/* how many blocks we want to allocate */
161 	unsigned int len;
162 	/* logical block in target inode */
163 	ext4_lblk_t logical;
164 	/* the closest logical allocated block to the left */
165 	ext4_lblk_t lleft;
166 	/* the closest logical allocated block to the right */
167 	ext4_lblk_t lright;
168 	/* phys. target (a hint) */
169 	ext4_fsblk_t goal;
170 	/* phys. block for the closest logical allocated block to the left */
171 	ext4_fsblk_t pleft;
172 	/* phys. block for the closest logical allocated block to the right */
173 	ext4_fsblk_t pright;
174 	/* flags. see above EXT4_MB_HINT_* */
175 	unsigned int flags;
176 };
177 
178 /*
179  * Logical to physical block mapping, used by ext4_map_blocks()
180  *
181  * This structure is used to pass requests into ext4_map_blocks() as
182  * well as to store the information returned by ext4_map_blocks().  It
183  * takes less room on the stack than a struct buffer_head.
184  */
185 #define EXT4_MAP_NEW		BIT(BH_New)
186 #define EXT4_MAP_MAPPED		BIT(BH_Mapped)
187 #define EXT4_MAP_UNWRITTEN	BIT(BH_Unwritten)
188 #define EXT4_MAP_BOUNDARY	BIT(BH_Boundary)
189 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
190 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
191 
192 struct ext4_map_blocks {
193 	ext4_fsblk_t m_pblk;
194 	ext4_lblk_t m_lblk;
195 	unsigned int m_len;
196 	unsigned int m_flags;
197 };
198 
199 /*
200  * Block validity checking, system zone rbtree.
201  */
202 struct ext4_system_blocks {
203 	struct rb_root root;
204 	struct rcu_head rcu;
205 };
206 
207 /*
208  * Flags for ext4_io_end->flags
209  */
210 #define	EXT4_IO_END_UNWRITTEN	0x0001
211 
212 struct ext4_io_end_vec {
213 	struct list_head list;		/* list of io_end_vec */
214 	loff_t offset;			/* offset in the file */
215 	ssize_t size;			/* size of the extent */
216 };
217 
218 /*
219  * For converting unwritten extents on a work queue. 'handle' is used for
220  * buffered writeback.
221  */
222 typedef struct ext4_io_end {
223 	struct list_head	list;		/* per-file finished IO list */
224 	handle_t		*handle;	/* handle reserved for extent
225 						 * conversion */
226 	struct inode		*inode;		/* file being written to */
227 	struct bio		*bio;		/* Linked list of completed
228 						 * bios covering the extent */
229 	unsigned int		flag;		/* unwritten or not */
230 	atomic_t		count;		/* reference counter */
231 	struct list_head	list_vec;	/* list of ext4_io_end_vec */
232 } ext4_io_end_t;
233 
234 struct ext4_io_submit {
235 	struct writeback_control *io_wbc;
236 	struct bio		*io_bio;
237 	ext4_io_end_t		*io_end;
238 	sector_t		io_next_block;
239 };
240 
241 /*
242  * Special inodes numbers
243  */
244 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
245 #define EXT4_ROOT_INO		 2	/* Root inode */
246 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
247 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
248 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
249 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
250 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
251 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
252 
253 /* First non-reserved inode for old ext4 filesystems */
254 #define EXT4_GOOD_OLD_FIRST_INO	11
255 
256 /*
257  * Maximal count of links to a file
258  */
259 #define EXT4_LINK_MAX		65000
260 
261 /*
262  * Macro-instructions used to manage several block sizes
263  */
264 #define EXT4_MIN_BLOCK_SIZE		1024
265 #define	EXT4_MAX_BLOCK_SIZE		65536
266 #define EXT4_MIN_BLOCK_LOG_SIZE		10
267 #define EXT4_MAX_BLOCK_LOG_SIZE		16
268 #define EXT4_MAX_CLUSTER_LOG_SIZE	30
269 #ifdef __KERNEL__
270 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
271 #else
272 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
273 #endif
274 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
275 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
276 					 EXT4_SB(s)->s_cluster_bits)
277 #ifdef __KERNEL__
278 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
279 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
280 #else
281 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
282 #endif
283 #ifdef __KERNEL__
284 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
285 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
286 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
287 #else
288 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
289 				 EXT4_GOOD_OLD_INODE_SIZE : \
290 				 (s)->s_inode_size)
291 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
292 				 EXT4_GOOD_OLD_FIRST_INO : \
293 				 (s)->s_first_ino)
294 #endif
295 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
296 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
297 	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
298 								  blkbits))
299 
300 /* Translate a block number to a cluster number */
301 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
302 /* Translate a cluster number to a block number */
303 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
304 /* Translate # of blks to # of clusters */
305 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
306 				 (sbi)->s_cluster_bits)
307 /* Mask out the low bits to get the starting block of the cluster */
308 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
309 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
310 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
311 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
312 /* Fill in the low bits to get the last block of the cluster */
313 #define EXT4_LBLK_CFILL(sbi, lblk) ((lblk) |				\
314 				    ((ext4_lblk_t) (sbi)->s_cluster_ratio - 1))
315 /* Get the cluster offset */
316 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
317 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
318 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
319 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
320 
321 /*
322  * Structure of a blocks group descriptor
323  */
324 struct ext4_group_desc
325 {
326 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
327 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
328 	__le32	bg_inode_table_lo;	/* Inodes table block */
329 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
330 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
331 	__le16	bg_used_dirs_count_lo;	/* Directories count */
332 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
333 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
334 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
335 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
336 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
337 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
338 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
339 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
340 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
341 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
342 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
343 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
344 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
345 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
346 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
347 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
348 	__u32   bg_reserved;
349 };
350 
351 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
352 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
353 	 sizeof(__le16))
354 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
355 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
356 	 sizeof(__le16))
357 
358 /*
359  * Structure of a flex block group info
360  */
361 
362 struct flex_groups {
363 	atomic64_t	free_clusters;
364 	atomic_t	free_inodes;
365 	atomic_t	used_dirs;
366 };
367 
368 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
369 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
370 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
371 
372 /*
373  * Macro-instructions used to manage group descriptors
374  */
375 #define EXT4_MIN_DESC_SIZE		32
376 #define EXT4_MIN_DESC_SIZE_64BIT	64
377 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
378 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
379 #ifdef __KERNEL__
380 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
381 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
382 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
383 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
384 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
385 #else
386 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
387 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
388 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
389 #endif
390 
391 /*
392  * Constants relative to the data blocks
393  */
394 #define	EXT4_NDIR_BLOCKS		12
395 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
396 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
397 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
398 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
399 
400 /*
401  * Inode flags
402  */
403 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
404 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
405 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
406 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
407 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
408 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
409 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
410 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
411 /* Reserved for compression usage... */
412 #define EXT4_DIRTY_FL			0x00000100
413 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
414 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
415 	/* nb: was previously EXT2_ECOMPR_FL */
416 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
417 /* End compression flags --- maybe not all used */
418 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
419 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
420 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
421 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
422 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
423 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
424 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
425 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
426 #define EXT4_VERITY_FL			0x00100000 /* Verity protected inode */
427 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
428 /* 0x00400000 was formerly EXT4_EOFBLOCKS_FL */
429 
430 #define EXT4_DAX_FL			0x02000000 /* Inode is DAX */
431 
432 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
433 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
434 #define EXT4_CASEFOLD_FL		0x40000000 /* Casefolded directory */
435 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
436 
437 #define EXT4_FL_USER_VISIBLE		0x725BDFFF /* User visible flags */
438 #define EXT4_FL_USER_MODIFIABLE		0x624BC0FF /* User modifiable flags */
439 
440 /* Flags we can manipulate with through EXT4_IOC_FSSETXATTR */
441 #define EXT4_FL_XFLAG_VISIBLE		(EXT4_SYNC_FL | \
442 					 EXT4_IMMUTABLE_FL | \
443 					 EXT4_APPEND_FL | \
444 					 EXT4_NODUMP_FL | \
445 					 EXT4_NOATIME_FL | \
446 					 EXT4_PROJINHERIT_FL | \
447 					 EXT4_DAX_FL)
448 
449 /* Flags that should be inherited by new inodes from their parent. */
450 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
451 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
452 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
453 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
454 			   EXT4_PROJINHERIT_FL | EXT4_CASEFOLD_FL |\
455 			   EXT4_DAX_FL)
456 
457 /* Flags that are appropriate for regular files (all but dir-specific ones). */
458 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL | EXT4_CASEFOLD_FL |\
459 			   EXT4_PROJINHERIT_FL))
460 
461 /* Flags that are appropriate for non-directories/regular files. */
462 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
463 
464 /* The only flags that should be swapped */
465 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
466 
467 /* Flags which are mutually exclusive to DAX */
468 #define EXT4_DAX_MUT_EXCL (EXT4_VERITY_FL | EXT4_ENCRYPT_FL |\
469 			   EXT4_JOURNAL_DATA_FL)
470 
471 /* Mask out flags that are inappropriate for the given type of inode. */
472 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
473 {
474 	if (S_ISDIR(mode))
475 		return flags;
476 	else if (S_ISREG(mode))
477 		return flags & EXT4_REG_FLMASK;
478 	else
479 		return flags & EXT4_OTHER_FLMASK;
480 }
481 
482 /*
483  * Inode flags used for atomic set/get
484  */
485 enum {
486 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
487 	EXT4_INODE_UNRM		= 1,	/* Undelete */
488 	EXT4_INODE_COMPR	= 2,	/* Compress file */
489 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
490 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
491 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
492 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
493 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
494 /* Reserved for compression usage... */
495 	EXT4_INODE_DIRTY	= 8,
496 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
497 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
498 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
499 /* End compression flags --- maybe not all used */
500 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
501 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
502 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
503 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
504 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
505 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
506 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
507 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
508 	EXT4_INODE_VERITY	= 20,	/* Verity protected inode */
509 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
510 /* 22 was formerly EXT4_INODE_EOFBLOCKS */
511 	EXT4_INODE_DAX		= 25,	/* Inode is DAX */
512 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
513 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
514 	EXT4_INODE_CASEFOLD	= 30,	/* Casefolded directory */
515 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
516 };
517 
518 /*
519  * Since it's pretty easy to mix up bit numbers and hex values, we use a
520  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
521  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
522  * any extra space in the compiled kernel image, otherwise, the build will fail.
523  * It's important that these values are the same, since we are using
524  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
525  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
526  * values found in ext2, ext3 and ext4 filesystems, and of course the values
527  * defined in e2fsprogs.
528  *
529  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
530  */
531 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
532 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
533 
534 static inline void ext4_check_flag_values(void)
535 {
536 	CHECK_FLAG_VALUE(SECRM);
537 	CHECK_FLAG_VALUE(UNRM);
538 	CHECK_FLAG_VALUE(COMPR);
539 	CHECK_FLAG_VALUE(SYNC);
540 	CHECK_FLAG_VALUE(IMMUTABLE);
541 	CHECK_FLAG_VALUE(APPEND);
542 	CHECK_FLAG_VALUE(NODUMP);
543 	CHECK_FLAG_VALUE(NOATIME);
544 	CHECK_FLAG_VALUE(DIRTY);
545 	CHECK_FLAG_VALUE(COMPRBLK);
546 	CHECK_FLAG_VALUE(NOCOMPR);
547 	CHECK_FLAG_VALUE(ENCRYPT);
548 	CHECK_FLAG_VALUE(INDEX);
549 	CHECK_FLAG_VALUE(IMAGIC);
550 	CHECK_FLAG_VALUE(JOURNAL_DATA);
551 	CHECK_FLAG_VALUE(NOTAIL);
552 	CHECK_FLAG_VALUE(DIRSYNC);
553 	CHECK_FLAG_VALUE(TOPDIR);
554 	CHECK_FLAG_VALUE(HUGE_FILE);
555 	CHECK_FLAG_VALUE(EXTENTS);
556 	CHECK_FLAG_VALUE(VERITY);
557 	CHECK_FLAG_VALUE(EA_INODE);
558 	CHECK_FLAG_VALUE(INLINE_DATA);
559 	CHECK_FLAG_VALUE(PROJINHERIT);
560 	CHECK_FLAG_VALUE(CASEFOLD);
561 	CHECK_FLAG_VALUE(RESERVED);
562 }
563 
564 /* Used to pass group descriptor data when online resize is done */
565 struct ext4_new_group_input {
566 	__u32 group;		/* Group number for this data */
567 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
568 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
569 	__u64 inode_table;	/* Absolute block number of inode table start */
570 	__u32 blocks_count;	/* Total number of blocks in this group */
571 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
572 	__u16 unused;
573 };
574 
575 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
576 struct compat_ext4_new_group_input {
577 	u32 group;
578 	compat_u64 block_bitmap;
579 	compat_u64 inode_bitmap;
580 	compat_u64 inode_table;
581 	u32 blocks_count;
582 	u16 reserved_blocks;
583 	u16 unused;
584 };
585 #endif
586 
587 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
588 struct ext4_new_group_data {
589 	__u32 group;
590 	__u64 block_bitmap;
591 	__u64 inode_bitmap;
592 	__u64 inode_table;
593 	__u32 blocks_count;
594 	__u16 reserved_blocks;
595 	__u16 mdata_blocks;
596 	__u32 free_clusters_count;
597 };
598 
599 /* Indexes used to index group tables in ext4_new_group_data */
600 enum {
601 	BLOCK_BITMAP = 0,	/* block bitmap */
602 	INODE_BITMAP,		/* inode bitmap */
603 	INODE_TABLE,		/* inode tables */
604 	GROUP_TABLE_COUNT,
605 };
606 
607 /*
608  * Flags used by ext4_map_blocks()
609  */
610 	/* Allocate any needed blocks and/or convert an unwritten
611 	   extent to be an initialized ext4 */
612 #define EXT4_GET_BLOCKS_CREATE			0x0001
613 	/* Request the creation of an unwritten extent */
614 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
615 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
616 						 EXT4_GET_BLOCKS_CREATE)
617 	/* Caller is from the delayed allocation writeout path
618 	 * finally doing the actual allocation of delayed blocks */
619 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
620 	/* caller is from the direct IO path, request to creation of an
621 	unwritten extents if not allocated, split the unwritten
622 	extent if blocks has been preallocated already*/
623 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
624 #define EXT4_GET_BLOCKS_CONVERT			0x0010
625 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
626 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
627 	/* Convert extent to initialized after IO complete */
628 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
629 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
630 	/* Eventual metadata allocation (due to growing extent tree)
631 	 * should not fail, so try to use reserved blocks for that.*/
632 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
633 	/* Don't normalize allocation size (used for fallocate) */
634 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
635 	/* Convert written extents to unwritten */
636 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
637 	/* Write zeros to newly created written extents */
638 #define EXT4_GET_BLOCKS_ZERO			0x0200
639 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
640 					EXT4_GET_BLOCKS_ZERO)
641 	/* Caller will submit data before dropping transaction handle. This
642 	 * allows jbd2 to avoid submitting data before commit. */
643 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
644 
645 /*
646  * The bit position of these flags must not overlap with any of the
647  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
648  * read_extent_tree_block(), ext4_split_extent_at(),
649  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
650  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
651  * caching the extents when reading from the extent tree while a
652  * truncate or punch hole operation is in progress.
653  */
654 #define EXT4_EX_NOCACHE				0x40000000
655 #define EXT4_EX_FORCE_CACHE			0x20000000
656 #define EXT4_EX_NOFAIL				0x10000000
657 
658 /*
659  * Flags used by ext4_free_blocks
660  */
661 #define EXT4_FREE_BLOCKS_METADATA		0x0001
662 #define EXT4_FREE_BLOCKS_FORGET			0x0002
663 #define EXT4_FREE_BLOCKS_VALIDATED		0x0004
664 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE		0x0008
665 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
666 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
667 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
668 
669 /*
670  * ioctl commands
671  */
672 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
673 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
674 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
675 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
676 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
677 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
678 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
679 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
680 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
681 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
682 #define EXT4_IOC_MIGRATE		_IO('f', 9)
683  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
684  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
685 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
686 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
687 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
688 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
689 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
690 #define EXT4_IOC_SET_ENCRYPTION_POLICY	FS_IOC_SET_ENCRYPTION_POLICY
691 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	FS_IOC_GET_ENCRYPTION_PWSALT
692 #define EXT4_IOC_GET_ENCRYPTION_POLICY	FS_IOC_GET_ENCRYPTION_POLICY
693 /* ioctl codes 19--39 are reserved for fscrypt */
694 #define EXT4_IOC_CLEAR_ES_CACHE		_IO('f', 40)
695 #define EXT4_IOC_GETSTATE		_IOW('f', 41, __u32)
696 #define EXT4_IOC_GET_ES_CACHE		_IOWR('f', 42, struct fiemap)
697 
698 #define EXT4_IOC_FSGETXATTR		FS_IOC_FSGETXATTR
699 #define EXT4_IOC_FSSETXATTR		FS_IOC_FSSETXATTR
700 
701 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
702 
703 /*
704  * Flags for going down operation
705  */
706 #define EXT4_GOING_FLAGS_DEFAULT		0x0	/* going down */
707 #define EXT4_GOING_FLAGS_LOGFLUSH		0x1	/* flush log but not data */
708 #define EXT4_GOING_FLAGS_NOLOGFLUSH		0x2	/* don't flush log nor data */
709 
710 /*
711  * Flags returned by EXT4_IOC_GETSTATE
712  *
713  * We only expose to userspace a subset of the state flags in
714  * i_state_flags
715  */
716 #define EXT4_STATE_FLAG_EXT_PRECACHED	0x00000001
717 #define EXT4_STATE_FLAG_NEW		0x00000002
718 #define EXT4_STATE_FLAG_NEWENTRY	0x00000004
719 #define EXT4_STATE_FLAG_DA_ALLOC_CLOSE	0x00000008
720 
721 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
722 /*
723  * ioctl commands in 32 bit emulation
724  */
725 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
726 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
727 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
728 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
729 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
730 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
731 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
732 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
733 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
734 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
735 #endif
736 
737 /*
738  * Returned by EXT4_IOC_GET_ES_CACHE as an additional possible flag.
739  * It indicates that the entry in extent status cache is for a hole.
740  */
741 #define EXT4_FIEMAP_EXTENT_HOLE		0x08000000
742 
743 /* Max physical block we can address w/o extents */
744 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
745 
746 /* Max logical block we can support */
747 #define EXT4_MAX_LOGICAL_BLOCK		0xFFFFFFFE
748 
749 /*
750  * Structure of an inode on the disk
751  */
752 struct ext4_inode {
753 	__le16	i_mode;		/* File mode */
754 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
755 	__le32	i_size_lo;	/* Size in bytes */
756 	__le32	i_atime;	/* Access time */
757 	__le32	i_ctime;	/* Inode Change time */
758 	__le32	i_mtime;	/* Modification time */
759 	__le32	i_dtime;	/* Deletion Time */
760 	__le16	i_gid;		/* Low 16 bits of Group Id */
761 	__le16	i_links_count;	/* Links count */
762 	__le32	i_blocks_lo;	/* Blocks count */
763 	__le32	i_flags;	/* File flags */
764 	union {
765 		struct {
766 			__le32  l_i_version;
767 		} linux1;
768 		struct {
769 			__u32  h_i_translator;
770 		} hurd1;
771 		struct {
772 			__u32  m_i_reserved1;
773 		} masix1;
774 	} osd1;				/* OS dependent 1 */
775 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
776 	__le32	i_generation;	/* File version (for NFS) */
777 	__le32	i_file_acl_lo;	/* File ACL */
778 	__le32	i_size_high;
779 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
780 	union {
781 		struct {
782 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
783 			__le16	l_i_file_acl_high;
784 			__le16	l_i_uid_high;	/* these 2 fields */
785 			__le16	l_i_gid_high;	/* were reserved2[0] */
786 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
787 			__le16	l_i_reserved;
788 		} linux2;
789 		struct {
790 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
791 			__u16	h_i_mode_high;
792 			__u16	h_i_uid_high;
793 			__u16	h_i_gid_high;
794 			__u32	h_i_author;
795 		} hurd2;
796 		struct {
797 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
798 			__le16	m_i_file_acl_high;
799 			__u32	m_i_reserved2[2];
800 		} masix2;
801 	} osd2;				/* OS dependent 2 */
802 	__le16	i_extra_isize;
803 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
804 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
805 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
806 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
807 	__le32  i_crtime;       /* File Creation time */
808 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
809 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
810 	__le32	i_projid;	/* Project ID */
811 };
812 
813 struct move_extent {
814 	__u32 reserved;		/* should be zero */
815 	__u32 donor_fd;		/* donor file descriptor */
816 	__u64 orig_start;	/* logical start offset in block for orig */
817 	__u64 donor_start;	/* logical start offset in block for donor */
818 	__u64 len;		/* block length to be moved */
819 	__u64 moved_len;	/* moved block length */
820 };
821 
822 #define EXT4_EPOCH_BITS 2
823 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
824 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
825 
826 /*
827  * Extended fields will fit into an inode if the filesystem was formatted
828  * with large inodes (-I 256 or larger) and there are not currently any EAs
829  * consuming all of the available space. For new inodes we always reserve
830  * enough space for the kernel's known extended fields, but for inodes
831  * created with an old kernel this might not have been the case. None of
832  * the extended inode fields is critical for correct filesystem operation.
833  * This macro checks if a certain field fits in the inode. Note that
834  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
835  */
836 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
837 	((offsetof(typeof(*ext4_inode), field) +	\
838 	  sizeof((ext4_inode)->field))			\
839 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
840 	    (einode)->i_extra_isize))			\
841 
842 /*
843  * We use an encoding that preserves the times for extra epoch "00":
844  *
845  * extra  msb of                         adjust for signed
846  * epoch  32-bit                         32-bit tv_sec to
847  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
848  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
849  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
850  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
851  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
852  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
853  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
854  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
855  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
856  *
857  * Note that previous versions of the kernel on 64-bit systems would
858  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
859  * 1970.  e2fsck will correct this, assuming that it is run on the
860  * affected filesystem before 2242.
861  */
862 
863 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
864 {
865 	u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
866 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
867 }
868 
869 static inline void ext4_decode_extra_time(struct timespec64 *time,
870 					  __le32 extra)
871 {
872 	if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK)))
873 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
874 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
875 }
876 
877 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)				\
878 do {										\
879 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
880 		(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	\
881 		(raw_inode)->xtime ## _extra =					\
882 				ext4_encode_extra_time(&(inode)->xtime);	\
883 		}								\
884 	else	\
885 		(raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (inode)->xtime.tv_sec, S32_MIN, S32_MAX));	\
886 } while (0)
887 
888 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
889 do {									       \
890 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
891 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
892 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
893 		(raw_inode)->xtime ## _extra =				       \
894 				ext4_encode_extra_time(&(einode)->xtime);      \
895 } while (0)
896 
897 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)				\
898 do {										\
899 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);	\
900 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {	\
901 		ext4_decode_extra_time(&(inode)->xtime,				\
902 				       raw_inode->xtime ## _extra);		\
903 		}								\
904 	else									\
905 		(inode)->xtime.tv_nsec = 0;					\
906 } while (0)
907 
908 
909 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
910 do {									       \
911 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
912 		(einode)->xtime.tv_sec = 				       \
913 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
914 	else								       \
915 		(einode)->xtime.tv_sec = 0;				       \
916 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
917 		ext4_decode_extra_time(&(einode)->xtime,		       \
918 				       raw_inode->xtime ## _extra);	       \
919 	else								       \
920 		(einode)->xtime.tv_nsec = 0;				       \
921 } while (0)
922 
923 #define i_disk_version osd1.linux1.l_i_version
924 
925 #if defined(__KERNEL__) || defined(__linux__)
926 #define i_reserved1	osd1.linux1.l_i_reserved1
927 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
928 #define i_blocks_high	osd2.linux2.l_i_blocks_high
929 #define i_uid_low	i_uid
930 #define i_gid_low	i_gid
931 #define i_uid_high	osd2.linux2.l_i_uid_high
932 #define i_gid_high	osd2.linux2.l_i_gid_high
933 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
934 
935 #elif defined(__GNU__)
936 
937 #define i_translator	osd1.hurd1.h_i_translator
938 #define i_uid_high	osd2.hurd2.h_i_uid_high
939 #define i_gid_high	osd2.hurd2.h_i_gid_high
940 #define i_author	osd2.hurd2.h_i_author
941 
942 #elif defined(__masix__)
943 
944 #define i_reserved1	osd1.masix1.m_i_reserved1
945 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
946 #define i_reserved2	osd2.masix2.m_i_reserved2
947 
948 #endif /* defined(__KERNEL__) || defined(__linux__) */
949 
950 #include "extents_status.h"
951 
952 /*
953  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
954  *
955  * These are needed to avoid lockdep false positives when we need to
956  * allocate blocks to the quota inode during ext4_map_blocks(), while
957  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
958  * do quota tracking for the quota inode, this avoids deadlock (as
959  * well as infinite recursion, since it isn't turtles all the way
960  * down...)
961  *
962  *  I_DATA_SEM_NORMAL - Used for most inodes
963  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
964  *			  where the second inode has larger inode number
965  *			  than the first
966  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
967  */
968 enum {
969 	I_DATA_SEM_NORMAL = 0,
970 	I_DATA_SEM_OTHER,
971 	I_DATA_SEM_QUOTA,
972 };
973 
974 
975 /*
976  * fourth extended file system inode data in memory
977  */
978 struct ext4_inode_info {
979 	__le32	i_data[15];	/* unconverted */
980 	__u32	i_dtime;
981 	ext4_fsblk_t	i_file_acl;
982 
983 	/*
984 	 * i_block_group is the number of the block group which contains
985 	 * this file's inode.  Constant across the lifetime of the inode,
986 	 * it is used for making block allocation decisions - we try to
987 	 * place a file's data blocks near its inode block, and new inodes
988 	 * near to their parent directory's inode.
989 	 */
990 	ext4_group_t	i_block_group;
991 	ext4_lblk_t	i_dir_start_lookup;
992 #if (BITS_PER_LONG < 64)
993 	unsigned long	i_state_flags;		/* Dynamic state flags */
994 #endif
995 	unsigned long	i_flags;
996 
997 	/*
998 	 * Extended attributes can be read independently of the main file
999 	 * data. Taking i_mutex even when reading would cause contention
1000 	 * between readers of EAs and writers of regular file data, so
1001 	 * instead we synchronize on xattr_sem when reading or changing
1002 	 * EAs.
1003 	 */
1004 	struct rw_semaphore xattr_sem;
1005 
1006 	struct list_head i_orphan;	/* unlinked but open inodes */
1007 
1008 	/*
1009 	 * i_disksize keeps track of what the inode size is ON DISK, not
1010 	 * in memory.  During truncate, i_size is set to the new size by
1011 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
1012 	 * set i_disksize to 0 until the truncate is actually under way.
1013 	 *
1014 	 * The intent is that i_disksize always represents the blocks which
1015 	 * are used by this file.  This allows recovery to restart truncate
1016 	 * on orphans if we crash during truncate.  We actually write i_disksize
1017 	 * into the on-disk inode when writing inodes out, instead of i_size.
1018 	 *
1019 	 * The only time when i_disksize and i_size may be different is when
1020 	 * a truncate is in progress.  The only things which change i_disksize
1021 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
1022 	 */
1023 	loff_t	i_disksize;
1024 
1025 	/*
1026 	 * i_data_sem is for serialising ext4_truncate() against
1027 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
1028 	 * data tree are chopped off during truncate. We can't do that in
1029 	 * ext4 because whenever we perform intermediate commits during
1030 	 * truncate, the inode and all the metadata blocks *must* be in a
1031 	 * consistent state which allows truncation of the orphans to restart
1032 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
1033 	 * by other means, so we have i_data_sem.
1034 	 */
1035 	struct rw_semaphore i_data_sem;
1036 	/*
1037 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
1038 	 * operations. We have to make sure that new page cannot be faulted in
1039 	 * a section of the inode that is being punched. We cannot easily use
1040 	 * i_data_sem for this since we need protection for the whole punch
1041 	 * operation and i_data_sem ranks below transaction start so we have
1042 	 * to occasionally drop it.
1043 	 */
1044 	struct rw_semaphore i_mmap_sem;
1045 	struct inode vfs_inode;
1046 	struct jbd2_inode *jinode;
1047 
1048 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
1049 
1050 	/*
1051 	 * File creation time. Its function is same as that of
1052 	 * struct timespec64 i_{a,c,m}time in the generic inode.
1053 	 */
1054 	struct timespec64 i_crtime;
1055 
1056 	/* mballoc */
1057 	struct list_head i_prealloc_list;
1058 	spinlock_t i_prealloc_lock;
1059 
1060 	/* extents status tree */
1061 	struct ext4_es_tree i_es_tree;
1062 	rwlock_t i_es_lock;
1063 	struct list_head i_es_list;
1064 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1065 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1066 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1067 					   extents to shrink. Protected by
1068 					   i_es_lock  */
1069 
1070 	/* ialloc */
1071 	ext4_group_t	i_last_alloc_group;
1072 
1073 	/* allocation reservation info for delalloc */
1074 	/* In case of bigalloc, this refer to clusters rather than blocks */
1075 	unsigned int i_reserved_data_blocks;
1076 
1077 	/* pending cluster reservations for bigalloc file systems */
1078 	struct ext4_pending_tree i_pending_tree;
1079 
1080 	/* on-disk additional length */
1081 	__u16 i_extra_isize;
1082 
1083 	/* Indicate the inline data space. */
1084 	u16 i_inline_off;
1085 	u16 i_inline_size;
1086 
1087 #ifdef CONFIG_QUOTA
1088 	/* quota space reservation, managed internally by quota code */
1089 	qsize_t i_reserved_quota;
1090 #endif
1091 
1092 	/* Lock protecting lists below */
1093 	spinlock_t i_completed_io_lock;
1094 	/*
1095 	 * Completed IOs that need unwritten extents handling and have
1096 	 * transaction reserved
1097 	 */
1098 	struct list_head i_rsv_conversion_list;
1099 	struct work_struct i_rsv_conversion_work;
1100 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1101 
1102 	spinlock_t i_block_reservation_lock;
1103 
1104 	/*
1105 	 * Transactions that contain inode's metadata needed to complete
1106 	 * fsync and fdatasync, respectively.
1107 	 */
1108 	tid_t i_sync_tid;
1109 	tid_t i_datasync_tid;
1110 
1111 #ifdef CONFIG_QUOTA
1112 	struct dquot *i_dquot[MAXQUOTAS];
1113 #endif
1114 
1115 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1116 	__u32 i_csum_seed;
1117 
1118 	kprojid_t i_projid;
1119 };
1120 
1121 /*
1122  * File system states
1123  */
1124 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1125 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1126 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1127 
1128 /*
1129  * Misc. filesystem flags
1130  */
1131 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1132 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1133 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1134 
1135 /*
1136  * Mount flags set via mount options or defaults
1137  */
1138 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1139 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1140 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1141 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1142 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1143 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1144 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1145 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1146 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1147 #ifdef CONFIG_FS_DAX
1148 #define EXT4_MOUNT_DAX_ALWAYS		0x00200	/* Direct Access */
1149 #else
1150 #define EXT4_MOUNT_DAX_ALWAYS		0
1151 #endif
1152 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1153 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1154 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1155 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1156 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1157 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1158 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1159 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1160 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1161 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1162 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1163 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1164 						 * enable enforcement for hidden
1165 						 * quota files */
1166 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1167 						  * enforcement for hidden quota
1168 						  * files */
1169 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1170 						  * enforcement */
1171 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1172 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1173 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1174 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
1175 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1176 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1177 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1178 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1179 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1180 
1181 /*
1182  * Mount flags set either automatically (could not be set by mount option)
1183  * based on per file system feature or property or in special cases such as
1184  * distinguishing between explicit mount option definition and default.
1185  */
1186 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1187 						      specified delalloc */
1188 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1189 						      size of blocksize * 8
1190 						      blocks */
1191 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1192 						      file systems */
1193 #define EXT4_MOUNT2_DAX_NEVER		0x00000008 /* Do not allow Direct Access */
1194 #define EXT4_MOUNT2_DAX_INODE		0x00000010 /* For printing options only */
1195 
1196 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1197 						specified journal checksum */
1198 
1199 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1200 						~EXT4_MOUNT_##opt
1201 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1202 						EXT4_MOUNT_##opt
1203 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1204 					 EXT4_MOUNT_##opt)
1205 
1206 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1207 						~EXT4_MOUNT2_##opt
1208 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1209 						EXT4_MOUNT2_##opt
1210 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1211 					 EXT4_MOUNT2_##opt)
1212 
1213 #define ext4_test_and_set_bit		__test_and_set_bit_le
1214 #define ext4_set_bit			__set_bit_le
1215 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1216 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1217 #define ext4_clear_bit			__clear_bit_le
1218 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1219 #define ext4_test_bit			test_bit_le
1220 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1221 #define ext4_find_next_bit		find_next_bit_le
1222 
1223 extern void ext4_set_bits(void *bm, int cur, int len);
1224 
1225 /*
1226  * Maximal mount counts between two filesystem checks
1227  */
1228 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1229 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1230 
1231 /*
1232  * Behaviour when detecting errors
1233  */
1234 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1235 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1236 #define EXT4_ERRORS_PANIC		3	/* Panic */
1237 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1238 
1239 /* Metadata checksum algorithm codes */
1240 #define EXT4_CRC32C_CHKSUM		1
1241 
1242 /*
1243  * Structure of the super block
1244  */
1245 struct ext4_super_block {
1246 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1247 	__le32	s_blocks_count_lo;	/* Blocks count */
1248 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1249 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1250 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1251 	__le32	s_first_data_block;	/* First Data Block */
1252 	__le32	s_log_block_size;	/* Block size */
1253 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1254 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1255 	__le32	s_clusters_per_group;	/* # Clusters per group */
1256 	__le32	s_inodes_per_group;	/* # Inodes per group */
1257 	__le32	s_mtime;		/* Mount time */
1258 /*30*/	__le32	s_wtime;		/* Write time */
1259 	__le16	s_mnt_count;		/* Mount count */
1260 	__le16	s_max_mnt_count;	/* Maximal mount count */
1261 	__le16	s_magic;		/* Magic signature */
1262 	__le16	s_state;		/* File system state */
1263 	__le16	s_errors;		/* Behaviour when detecting errors */
1264 	__le16	s_minor_rev_level;	/* minor revision level */
1265 /*40*/	__le32	s_lastcheck;		/* time of last check */
1266 	__le32	s_checkinterval;	/* max. time between checks */
1267 	__le32	s_creator_os;		/* OS */
1268 	__le32	s_rev_level;		/* Revision level */
1269 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1270 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1271 	/*
1272 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1273 	 *
1274 	 * Note: the difference between the compatible feature set and
1275 	 * the incompatible feature set is that if there is a bit set
1276 	 * in the incompatible feature set that the kernel doesn't
1277 	 * know about, it should refuse to mount the filesystem.
1278 	 *
1279 	 * e2fsck's requirements are more strict; if it doesn't know
1280 	 * about a feature in either the compatible or incompatible
1281 	 * feature set, it must abort and not try to meddle with
1282 	 * things it doesn't understand...
1283 	 */
1284 	__le32	s_first_ino;		/* First non-reserved inode */
1285 	__le16  s_inode_size;		/* size of inode structure */
1286 	__le16	s_block_group_nr;	/* block group # of this superblock */
1287 	__le32	s_feature_compat;	/* compatible feature set */
1288 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1289 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1290 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1291 /*78*/	char	s_volume_name[16];	/* volume name */
1292 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
1293 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1294 	/*
1295 	 * Performance hints.  Directory preallocation should only
1296 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1297 	 */
1298 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1299 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1300 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1301 	/*
1302 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1303 	 */
1304 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1305 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1306 	__le32	s_journal_dev;		/* device number of journal file */
1307 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1308 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1309 	__u8	s_def_hash_version;	/* Default hash version to use */
1310 	__u8	s_jnl_backup_type;
1311 	__le16  s_desc_size;		/* size of group descriptor */
1312 /*100*/	__le32	s_default_mount_opts;
1313 	__le32	s_first_meta_bg;	/* First metablock block group */
1314 	__le32	s_mkfs_time;		/* When the filesystem was created */
1315 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1316 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1317 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1318 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1319 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1320 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1321 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1322 	__le32	s_flags;		/* Miscellaneous flags */
1323 	__le16  s_raid_stride;		/* RAID stride */
1324 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1325 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1326 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1327 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1328 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1329 	__u8	s_encryption_level;	/* versioning level for encryption */
1330 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1331 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1332 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1333 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1334 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1335 					      snapshot's future use */
1336 	__le32	s_snapshot_list;	/* inode number of the head of the
1337 					   on-disk snapshot list */
1338 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1339 	__le32	s_error_count;		/* number of fs errors */
1340 	__le32	s_first_error_time;	/* first time an error happened */
1341 	__le32	s_first_error_ino;	/* inode involved in first error */
1342 	__le64	s_first_error_block;	/* block involved of first error */
1343 	__u8	s_first_error_func[32] __nonstring;	/* function where the error happened */
1344 	__le32	s_first_error_line;	/* line number where error happened */
1345 	__le32	s_last_error_time;	/* most recent time of an error */
1346 	__le32	s_last_error_ino;	/* inode involved in last error */
1347 	__le32	s_last_error_line;	/* line number where error happened */
1348 	__le64	s_last_error_block;	/* block involved of last error */
1349 	__u8	s_last_error_func[32] __nonstring;	/* function where the error happened */
1350 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1351 	__u8	s_mount_opts[64];
1352 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1353 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1354 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1355 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1356 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1357 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1358 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1359 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1360 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1361 	__u8	s_wtime_hi;
1362 	__u8	s_mtime_hi;
1363 	__u8	s_mkfs_time_hi;
1364 	__u8	s_lastcheck_hi;
1365 	__u8	s_first_error_time_hi;
1366 	__u8	s_last_error_time_hi;
1367 	__u8	s_first_error_errcode;
1368 	__u8    s_last_error_errcode;
1369 	__le16  s_encoding;		/* Filename charset encoding */
1370 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
1371 	__le32	s_reserved[95];		/* Padding to the end of the block */
1372 	__le32	s_checksum;		/* crc32c(superblock) */
1373 };
1374 
1375 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1376 
1377 #ifdef __KERNEL__
1378 
1379 /*
1380  * run-time mount flags
1381  */
1382 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1383 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1384 
1385 #ifdef CONFIG_FS_ENCRYPTION
1386 #define DUMMY_ENCRYPTION_ENABLED(sbi) ((sbi)->s_dummy_enc_ctx.ctx != NULL)
1387 #else
1388 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1389 #endif
1390 
1391 /* Number of quota types we support */
1392 #define EXT4_MAXQUOTAS 3
1393 
1394 #define EXT4_ENC_UTF8_12_1	1
1395 
1396 /*
1397  * Flags for ext4_sb_info.s_encoding_flags.
1398  */
1399 #define EXT4_ENC_STRICT_MODE_FL	(1 << 0)
1400 
1401 #define ext4_has_strict_mode(sbi) \
1402 	(sbi->s_encoding_flags & EXT4_ENC_STRICT_MODE_FL)
1403 
1404 /*
1405  * fourth extended-fs super-block data in memory
1406  */
1407 struct ext4_sb_info {
1408 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1409 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1410 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1411 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1412 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1413 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1414 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1415 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1416 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1417 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1418 	unsigned long s_overhead;  /* # of fs overhead clusters */
1419 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1420 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1421 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1422 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1423 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1424 	struct buffer_head * __rcu *s_group_desc;
1425 	unsigned int s_mount_opt;
1426 	unsigned int s_mount_opt2;
1427 	unsigned int s_mount_flags;
1428 	unsigned int s_def_mount_opt;
1429 	ext4_fsblk_t s_sb_block;
1430 	atomic64_t s_resv_clusters;
1431 	kuid_t s_resuid;
1432 	kgid_t s_resgid;
1433 	unsigned short s_mount_state;
1434 	unsigned short s_pad;
1435 	int s_addr_per_block_bits;
1436 	int s_desc_per_block_bits;
1437 	int s_inode_size;
1438 	int s_first_ino;
1439 	unsigned int s_inode_readahead_blks;
1440 	unsigned int s_inode_goal;
1441 	u32 s_hash_seed[4];
1442 	int s_def_hash_version;
1443 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1444 	struct percpu_counter s_freeclusters_counter;
1445 	struct percpu_counter s_freeinodes_counter;
1446 	struct percpu_counter s_dirs_counter;
1447 	struct percpu_counter s_dirtyclusters_counter;
1448 	struct blockgroup_lock *s_blockgroup_lock;
1449 	struct proc_dir_entry *s_proc;
1450 	struct kobject s_kobj;
1451 	struct completion s_kobj_unregister;
1452 	struct super_block *s_sb;
1453 #ifdef CONFIG_UNICODE
1454 	struct unicode_map *s_encoding;
1455 	__u16 s_encoding_flags;
1456 #endif
1457 
1458 	/* Journaling */
1459 	struct journal_s *s_journal;
1460 	struct list_head s_orphan;
1461 	struct mutex s_orphan_lock;
1462 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1463 	unsigned long s_commit_interval;
1464 	u32 s_max_batch_time;
1465 	u32 s_min_batch_time;
1466 	struct block_device *journal_bdev;
1467 #ifdef CONFIG_QUOTA
1468 	/* Names of quota files with journalled quota */
1469 	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1470 	int s_jquota_fmt;			/* Format of quota to use */
1471 #endif
1472 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1473 	struct ext4_system_blocks __rcu *system_blks;
1474 
1475 #ifdef EXTENTS_STATS
1476 	/* ext4 extents stats */
1477 	unsigned long s_ext_min;
1478 	unsigned long s_ext_max;
1479 	unsigned long s_depth_max;
1480 	spinlock_t s_ext_stats_lock;
1481 	unsigned long s_ext_blocks;
1482 	unsigned long s_ext_extents;
1483 #endif
1484 
1485 	/* for buddy allocator */
1486 	struct ext4_group_info ** __rcu *s_group_info;
1487 	struct inode *s_buddy_cache;
1488 	spinlock_t s_md_lock;
1489 	unsigned short *s_mb_offsets;
1490 	unsigned int *s_mb_maxs;
1491 	unsigned int s_group_info_size;
1492 	unsigned int s_mb_free_pending;
1493 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1494 						   after commit completed */
1495 
1496 	/* tunables */
1497 	unsigned long s_stripe;
1498 	unsigned int s_mb_stream_request;
1499 	unsigned int s_mb_max_to_scan;
1500 	unsigned int s_mb_min_to_scan;
1501 	unsigned int s_mb_stats;
1502 	unsigned int s_mb_order2_reqs;
1503 	unsigned int s_mb_group_prealloc;
1504 	unsigned int s_max_dir_size_kb;
1505 	/* where last allocation was done - for stream allocation */
1506 	unsigned long s_mb_last_group;
1507 	unsigned long s_mb_last_start;
1508 
1509 	/* stats for buddy allocator */
1510 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1511 	atomic_t s_bal_success;	/* we found long enough chunks */
1512 	atomic_t s_bal_allocated;	/* in blocks */
1513 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1514 	atomic_t s_bal_goals;	/* goal hits */
1515 	atomic_t s_bal_breaks;	/* too long searches */
1516 	atomic_t s_bal_2orders;	/* 2^order hits */
1517 	spinlock_t s_bal_lock;
1518 	unsigned long s_mb_buddies_generated;
1519 	unsigned long long s_mb_generation_time;
1520 	atomic_t s_mb_lost_chunks;
1521 	atomic_t s_mb_preallocated;
1522 	atomic_t s_mb_discarded;
1523 	atomic_t s_lock_busy;
1524 
1525 	/* locality groups */
1526 	struct ext4_locality_group __percpu *s_locality_groups;
1527 
1528 	/* for write statistics */
1529 	unsigned long s_sectors_written_start;
1530 	u64 s_kbytes_written;
1531 
1532 	/* the size of zero-out chunk */
1533 	unsigned int s_extent_max_zeroout_kb;
1534 
1535 	unsigned int s_log_groups_per_flex;
1536 	struct flex_groups * __rcu *s_flex_groups;
1537 	ext4_group_t s_flex_groups_allocated;
1538 
1539 	/* workqueue for reserved extent conversions (buffered io) */
1540 	struct workqueue_struct *rsv_conversion_wq;
1541 
1542 	/* timer for periodic error stats printing */
1543 	struct timer_list s_err_report;
1544 
1545 	/* Lazy inode table initialization info */
1546 	struct ext4_li_request *s_li_request;
1547 	/* Wait multiplier for lazy initialization thread */
1548 	unsigned int s_li_wait_mult;
1549 
1550 	/* Kernel thread for multiple mount protection */
1551 	struct task_struct *s_mmp_tsk;
1552 
1553 	/* record the last minlen when FITRIM is called. */
1554 	atomic_t s_last_trim_minblks;
1555 
1556 	/* Reference to checksum algorithm driver via cryptoapi */
1557 	struct crypto_shash *s_chksum_driver;
1558 
1559 	/* Precomputed FS UUID checksum for seeding other checksums */
1560 	__u32 s_csum_seed;
1561 
1562 	/* Reclaim extents from extent status tree */
1563 	struct shrinker s_es_shrinker;
1564 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1565 	long s_es_nr_inode;
1566 	struct ext4_es_stats s_es_stats;
1567 	struct mb_cache *s_ea_block_cache;
1568 	struct mb_cache *s_ea_inode_cache;
1569 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1570 
1571 	/* Ratelimit ext4 messages. */
1572 	struct ratelimit_state s_err_ratelimit_state;
1573 	struct ratelimit_state s_warning_ratelimit_state;
1574 	struct ratelimit_state s_msg_ratelimit_state;
1575 
1576 	/* Encryption context for '-o test_dummy_encryption' */
1577 	struct fscrypt_dummy_context s_dummy_enc_ctx;
1578 
1579 	/*
1580 	 * Barrier between writepages ops and changing any inode's JOURNAL_DATA
1581 	 * or EXTENTS flag.
1582 	 */
1583 	struct percpu_rw_semaphore s_writepages_rwsem;
1584 	struct dax_device *s_daxdev;
1585 #ifdef CONFIG_EXT4_DEBUG
1586 	unsigned long s_simulate_fail;
1587 #endif
1588 };
1589 
1590 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1591 {
1592 	return sb->s_fs_info;
1593 }
1594 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1595 {
1596 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1597 }
1598 
1599 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1600 {
1601 	return ino == EXT4_ROOT_INO ||
1602 		(ino >= EXT4_FIRST_INO(sb) &&
1603 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1604 }
1605 
1606 /*
1607  * Returns: sbi->field[index]
1608  * Used to access an array element from the following sbi fields which require
1609  * rcu protection to avoid dereferencing an invalid pointer due to reassignment
1610  * - s_group_desc
1611  * - s_group_info
1612  * - s_flex_group
1613  */
1614 #define sbi_array_rcu_deref(sbi, field, index)				   \
1615 ({									   \
1616 	typeof(*((sbi)->field)) _v;					   \
1617 	rcu_read_lock();						   \
1618 	_v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index];	   \
1619 	rcu_read_unlock();						   \
1620 	_v;								   \
1621 })
1622 
1623 /*
1624  * Simulate_fail codes
1625  */
1626 #define EXT4_SIM_BBITMAP_EIO	1
1627 #define EXT4_SIM_BBITMAP_CRC	2
1628 #define EXT4_SIM_IBITMAP_EIO	3
1629 #define EXT4_SIM_IBITMAP_CRC	4
1630 #define EXT4_SIM_INODE_EIO	5
1631 #define EXT4_SIM_INODE_CRC	6
1632 #define EXT4_SIM_DIRBLOCK_EIO	7
1633 #define EXT4_SIM_DIRBLOCK_CRC	8
1634 
1635 static inline bool ext4_simulate_fail(struct super_block *sb,
1636 				     unsigned long code)
1637 {
1638 #ifdef CONFIG_EXT4_DEBUG
1639 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1640 
1641 	if (unlikely(sbi->s_simulate_fail == code)) {
1642 		sbi->s_simulate_fail = 0;
1643 		return true;
1644 	}
1645 #endif
1646 	return false;
1647 }
1648 
1649 static inline void ext4_simulate_fail_bh(struct super_block *sb,
1650 					 struct buffer_head *bh,
1651 					 unsigned long code)
1652 {
1653 	if (!IS_ERR(bh) && ext4_simulate_fail(sb, code))
1654 		clear_buffer_uptodate(bh);
1655 }
1656 
1657 /*
1658  * Error number codes for s_{first,last}_error_errno
1659  *
1660  * Linux errno numbers are architecture specific, so we need to translate
1661  * them into something which is architecture independent.   We don't define
1662  * codes for all errno's; just the ones which are most likely to be the cause
1663  * of an ext4_error() call.
1664  */
1665 #define EXT4_ERR_UNKNOWN	 1
1666 #define EXT4_ERR_EIO		 2
1667 #define EXT4_ERR_ENOMEM		 3
1668 #define EXT4_ERR_EFSBADCRC	 4
1669 #define EXT4_ERR_EFSCORRUPTED	 5
1670 #define EXT4_ERR_ENOSPC		 6
1671 #define EXT4_ERR_ENOKEY		 7
1672 #define EXT4_ERR_EROFS		 8
1673 #define EXT4_ERR_EFBIG		 9
1674 #define EXT4_ERR_EEXIST		10
1675 #define EXT4_ERR_ERANGE		11
1676 #define EXT4_ERR_EOVERFLOW	12
1677 #define EXT4_ERR_EBUSY		13
1678 #define EXT4_ERR_ENOTDIR	14
1679 #define EXT4_ERR_ENOTEMPTY	15
1680 #define EXT4_ERR_ESHUTDOWN	16
1681 #define EXT4_ERR_EFAULT		17
1682 
1683 /*
1684  * Inode dynamic state flags
1685  */
1686 enum {
1687 	EXT4_STATE_JDATA,		/* journaled data exists */
1688 	EXT4_STATE_NEW,			/* inode is newly created */
1689 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1690 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1691 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1692 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1693 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1694 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1695 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1696 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1697 	EXT4_STATE_VERITY_IN_PROGRESS,	/* building fs-verity Merkle tree */
1698 };
1699 
1700 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1701 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1702 {									\
1703 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1704 }									\
1705 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1706 {									\
1707 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1708 }									\
1709 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1710 {									\
1711 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1712 }
1713 
1714 /* Add these declarations here only so that these functions can be
1715  * found by name.  Otherwise, they are very hard to locate. */
1716 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1717 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1718 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1719 EXT4_INODE_BIT_FNS(flag, flags, 0)
1720 
1721 /* Add these declarations here only so that these functions can be
1722  * found by name.  Otherwise, they are very hard to locate. */
1723 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1724 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1725 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1726 #if (BITS_PER_LONG < 64)
1727 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1728 
1729 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1730 {
1731 	(ei)->i_state_flags = 0;
1732 }
1733 #else
1734 EXT4_INODE_BIT_FNS(state, flags, 32)
1735 
1736 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1737 {
1738 	/* We depend on the fact that callers will set i_flags */
1739 }
1740 #endif
1741 #else
1742 /* Assume that user mode programs are passing in an ext4fs superblock, not
1743  * a kernel struct super_block.  This will allow us to call the feature-test
1744  * macros from user land. */
1745 #define EXT4_SB(sb)	(sb)
1746 #endif
1747 
1748 static inline bool ext4_verity_in_progress(struct inode *inode)
1749 {
1750 	return IS_ENABLED(CONFIG_FS_VERITY) &&
1751 	       ext4_test_inode_state(inode, EXT4_STATE_VERITY_IN_PROGRESS);
1752 }
1753 
1754 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1755 
1756 /*
1757  * Codes for operating systems
1758  */
1759 #define EXT4_OS_LINUX		0
1760 #define EXT4_OS_HURD		1
1761 #define EXT4_OS_MASIX		2
1762 #define EXT4_OS_FREEBSD		3
1763 #define EXT4_OS_LITES		4
1764 
1765 /*
1766  * Revision levels
1767  */
1768 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1769 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1770 
1771 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1772 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1773 
1774 #define EXT4_GOOD_OLD_INODE_SIZE 128
1775 
1776 #define EXT4_EXTRA_TIMESTAMP_MAX	(((s64)1 << 34) - 1  + S32_MIN)
1777 #define EXT4_NON_EXTRA_TIMESTAMP_MAX	S32_MAX
1778 #define EXT4_TIMESTAMP_MIN		S32_MIN
1779 
1780 /*
1781  * Feature set definitions
1782  */
1783 
1784 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1785 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1786 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1787 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1788 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1789 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1790 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1791 #define EXT4_FEATURE_COMPAT_STABLE_INODES	0x0800
1792 
1793 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1794 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1795 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1796 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1797 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1798 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1799 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1800 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1801 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1802 /*
1803  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1804  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1805  * all other data structures' checksums.  However, the METADATA_CSUM and
1806  * GDT_CSUM bits are mutually exclusive.
1807  */
1808 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1809 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1810 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1811 #define EXT4_FEATURE_RO_COMPAT_VERITY		0x8000
1812 
1813 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1814 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1815 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1816 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1817 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1818 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1819 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1820 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1821 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1822 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1823 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1824 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1825 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1826 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1827 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1828 #define EXT4_FEATURE_INCOMPAT_CASEFOLD		0x20000
1829 
1830 extern void ext4_update_dynamic_rev(struct super_block *sb);
1831 
1832 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1833 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1834 { \
1835 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1836 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1837 } \
1838 static inline void ext4_set_feature_##name(struct super_block *sb) \
1839 { \
1840 	ext4_update_dynamic_rev(sb); \
1841 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1842 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1843 } \
1844 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1845 { \
1846 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1847 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1848 }
1849 
1850 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1851 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1852 { \
1853 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1854 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1855 } \
1856 static inline void ext4_set_feature_##name(struct super_block *sb) \
1857 { \
1858 	ext4_update_dynamic_rev(sb); \
1859 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1860 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1861 } \
1862 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1863 { \
1864 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1865 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1866 }
1867 
1868 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1869 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1870 { \
1871 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1872 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1873 } \
1874 static inline void ext4_set_feature_##name(struct super_block *sb) \
1875 { \
1876 	ext4_update_dynamic_rev(sb); \
1877 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
1878 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1879 } \
1880 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1881 { \
1882 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1883 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1884 }
1885 
1886 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1887 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1888 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1889 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1890 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1891 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1892 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1893 EXT4_FEATURE_COMPAT_FUNCS(stable_inodes,	STABLE_INODES)
1894 
1895 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1896 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1897 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1898 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1899 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1900 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1901 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1902 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1903 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1904 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1905 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1906 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1907 EXT4_FEATURE_RO_COMPAT_FUNCS(verity,		VERITY)
1908 
1909 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1910 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
1911 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
1912 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
1913 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
1914 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
1915 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
1916 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
1917 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
1918 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
1919 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
1920 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
1921 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
1922 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
1923 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
1924 EXT4_FEATURE_INCOMPAT_FUNCS(casefold,		CASEFOLD)
1925 
1926 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1927 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1928 					 EXT4_FEATURE_INCOMPAT_META_BG)
1929 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1930 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1931 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1932 
1933 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1934 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1935 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1936 					 EXT4_FEATURE_INCOMPAT_META_BG)
1937 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1938 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1939 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1940 
1941 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1942 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1943 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1944 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1945 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1946 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1947 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1948 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
1949 					 EXT4_FEATURE_INCOMPAT_MMP | \
1950 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1951 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1952 					 EXT4_FEATURE_INCOMPAT_CASEFOLD | \
1953 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
1954 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
1955 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1956 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1957 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1958 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1959 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1960 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1961 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1962 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1963 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1964 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
1965 					 EXT4_FEATURE_RO_COMPAT_PROJECT |\
1966 					 EXT4_FEATURE_RO_COMPAT_VERITY)
1967 
1968 #define EXTN_FEATURE_FUNCS(ver) \
1969 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1970 { \
1971 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1972 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1973 } \
1974 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1975 { \
1976 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1977 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1978 } \
1979 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1980 { \
1981 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1982 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1983 }
1984 
1985 EXTN_FEATURE_FUNCS(2)
1986 EXTN_FEATURE_FUNCS(3)
1987 EXTN_FEATURE_FUNCS(4)
1988 
1989 static inline bool ext4_has_compat_features(struct super_block *sb)
1990 {
1991 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1992 }
1993 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1994 {
1995 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1996 }
1997 static inline bool ext4_has_incompat_features(struct super_block *sb)
1998 {
1999 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
2000 }
2001 
2002 /*
2003  * Superblock flags
2004  */
2005 #define EXT4_FLAGS_RESIZING	0
2006 #define EXT4_FLAGS_SHUTDOWN	1
2007 #define EXT4_FLAGS_BDEV_IS_DAX	2
2008 
2009 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
2010 {
2011 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
2012 }
2013 
2014 
2015 /*
2016  * Default values for user and/or group using reserved blocks
2017  */
2018 #define	EXT4_DEF_RESUID		0
2019 #define	EXT4_DEF_RESGID		0
2020 
2021 /*
2022  * Default project ID
2023  */
2024 #define	EXT4_DEF_PROJID		0
2025 
2026 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
2027 
2028 /*
2029  * Default mount options
2030  */
2031 #define EXT4_DEFM_DEBUG		0x0001
2032 #define EXT4_DEFM_BSDGROUPS	0x0002
2033 #define EXT4_DEFM_XATTR_USER	0x0004
2034 #define EXT4_DEFM_ACL		0x0008
2035 #define EXT4_DEFM_UID16		0x0010
2036 #define EXT4_DEFM_JMODE		0x0060
2037 #define EXT4_DEFM_JMODE_DATA	0x0020
2038 #define EXT4_DEFM_JMODE_ORDERED	0x0040
2039 #define EXT4_DEFM_JMODE_WBACK	0x0060
2040 #define EXT4_DEFM_NOBARRIER	0x0100
2041 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
2042 #define EXT4_DEFM_DISCARD	0x0400
2043 #define EXT4_DEFM_NODELALLOC	0x0800
2044 
2045 /*
2046  * Default journal batch times
2047  */
2048 #define EXT4_DEF_MIN_BATCH_TIME	0
2049 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
2050 
2051 /*
2052  * Minimum number of groups in a flexgroup before we separate out
2053  * directories into the first block group of a flexgroup
2054  */
2055 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
2056 
2057 /*
2058  * Structure of a directory entry
2059  */
2060 #define EXT4_NAME_LEN 255
2061 
2062 struct ext4_dir_entry {
2063 	__le32	inode;			/* Inode number */
2064 	__le16	rec_len;		/* Directory entry length */
2065 	__le16	name_len;		/* Name length */
2066 	char	name[EXT4_NAME_LEN];	/* File name */
2067 };
2068 
2069 /*
2070  * The new version of the directory entry.  Since EXT4 structures are
2071  * stored in intel byte order, and the name_len field could never be
2072  * bigger than 255 chars, it's safe to reclaim the extra byte for the
2073  * file_type field.
2074  */
2075 struct ext4_dir_entry_2 {
2076 	__le32	inode;			/* Inode number */
2077 	__le16	rec_len;		/* Directory entry length */
2078 	__u8	name_len;		/* Name length */
2079 	__u8	file_type;		/* See file type macros EXT4_FT_* below */
2080 	char	name[EXT4_NAME_LEN];	/* File name */
2081 };
2082 
2083 /*
2084  * This is a bogus directory entry at the end of each leaf block that
2085  * records checksums.
2086  */
2087 struct ext4_dir_entry_tail {
2088 	__le32	det_reserved_zero1;	/* Pretend to be unused */
2089 	__le16	det_rec_len;		/* 12 */
2090 	__u8	det_reserved_zero2;	/* Zero name length */
2091 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
2092 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
2093 };
2094 
2095 #define EXT4_DIRENT_TAIL(block, blocksize) \
2096 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
2097 					((blocksize) - \
2098 					 sizeof(struct ext4_dir_entry_tail))))
2099 
2100 /*
2101  * Ext4 directory file types.  Only the low 3 bits are used.  The
2102  * other bits are reserved for now.
2103  */
2104 #define EXT4_FT_UNKNOWN		0
2105 #define EXT4_FT_REG_FILE	1
2106 #define EXT4_FT_DIR		2
2107 #define EXT4_FT_CHRDEV		3
2108 #define EXT4_FT_BLKDEV		4
2109 #define EXT4_FT_FIFO		5
2110 #define EXT4_FT_SOCK		6
2111 #define EXT4_FT_SYMLINK		7
2112 
2113 #define EXT4_FT_MAX		8
2114 
2115 #define EXT4_FT_DIR_CSUM	0xDE
2116 
2117 /*
2118  * EXT4_DIR_PAD defines the directory entries boundaries
2119  *
2120  * NOTE: It must be a multiple of 4
2121  */
2122 #define EXT4_DIR_PAD			4
2123 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
2124 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
2125 					 ~EXT4_DIR_ROUND)
2126 #define EXT4_MAX_REC_LEN		((1<<16)-1)
2127 
2128 /*
2129  * If we ever get support for fs block sizes > page_size, we'll need
2130  * to remove the #if statements in the next two functions...
2131  */
2132 static inline unsigned int
2133 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
2134 {
2135 	unsigned len = le16_to_cpu(dlen);
2136 
2137 #if (PAGE_SIZE >= 65536)
2138 	if (len == EXT4_MAX_REC_LEN || len == 0)
2139 		return blocksize;
2140 	return (len & 65532) | ((len & 3) << 16);
2141 #else
2142 	return len;
2143 #endif
2144 }
2145 
2146 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2147 {
2148 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
2149 		BUG();
2150 #if (PAGE_SIZE >= 65536)
2151 	if (len < 65536)
2152 		return cpu_to_le16(len);
2153 	if (len == blocksize) {
2154 		if (blocksize == 65536)
2155 			return cpu_to_le16(EXT4_MAX_REC_LEN);
2156 		else
2157 			return cpu_to_le16(0);
2158 	}
2159 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2160 #else
2161 	return cpu_to_le16(len);
2162 #endif
2163 }
2164 
2165 /*
2166  * Hash Tree Directory indexing
2167  * (c) Daniel Phillips, 2001
2168  */
2169 
2170 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2171 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2172 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2173 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2174 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2175 
2176 /* Legal values for the dx_root hash_version field: */
2177 
2178 #define DX_HASH_LEGACY			0
2179 #define DX_HASH_HALF_MD4		1
2180 #define DX_HASH_TEA			2
2181 #define DX_HASH_LEGACY_UNSIGNED		3
2182 #define DX_HASH_HALF_MD4_UNSIGNED	4
2183 #define DX_HASH_TEA_UNSIGNED		5
2184 
2185 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2186 			      const void *address, unsigned int length)
2187 {
2188 	struct {
2189 		struct shash_desc shash;
2190 		char ctx[4];
2191 	} desc;
2192 
2193 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2194 
2195 	desc.shash.tfm = sbi->s_chksum_driver;
2196 	*(u32 *)desc.ctx = crc;
2197 
2198 	BUG_ON(crypto_shash_update(&desc.shash, address, length));
2199 
2200 	return *(u32 *)desc.ctx;
2201 }
2202 
2203 #ifdef __KERNEL__
2204 
2205 /* hash info structure used by the directory hash */
2206 struct dx_hash_info
2207 {
2208 	u32		hash;
2209 	u32		minor_hash;
2210 	int		hash_version;
2211 	u32		*seed;
2212 };
2213 
2214 
2215 /* 32 and 64 bit signed EOF for dx directories */
2216 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2217 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2218 
2219 
2220 /*
2221  * Control parameters used by ext4_htree_next_block
2222  */
2223 #define HASH_NB_ALWAYS		1
2224 
2225 struct ext4_filename {
2226 	const struct qstr *usr_fname;
2227 	struct fscrypt_str disk_name;
2228 	struct dx_hash_info hinfo;
2229 #ifdef CONFIG_FS_ENCRYPTION
2230 	struct fscrypt_str crypto_buf;
2231 #endif
2232 #ifdef CONFIG_UNICODE
2233 	struct fscrypt_str cf_name;
2234 #endif
2235 };
2236 
2237 #define fname_name(p) ((p)->disk_name.name)
2238 #define fname_len(p)  ((p)->disk_name.len)
2239 
2240 /*
2241  * Describe an inode's exact location on disk and in memory
2242  */
2243 struct ext4_iloc
2244 {
2245 	struct buffer_head *bh;
2246 	unsigned long offset;
2247 	ext4_group_t block_group;
2248 };
2249 
2250 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2251 {
2252 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2253 }
2254 
2255 static inline bool ext4_is_quota_file(struct inode *inode)
2256 {
2257 	return IS_NOQUOTA(inode) &&
2258 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2259 }
2260 
2261 /*
2262  * This structure is stuffed into the struct file's private_data field
2263  * for directories.  It is where we put information so that we can do
2264  * readdir operations in hash tree order.
2265  */
2266 struct dir_private_info {
2267 	struct rb_root	root;
2268 	struct rb_node	*curr_node;
2269 	struct fname	*extra_fname;
2270 	loff_t		last_pos;
2271 	__u32		curr_hash;
2272 	__u32		curr_minor_hash;
2273 	__u32		next_hash;
2274 };
2275 
2276 /* calculate the first block number of the group */
2277 static inline ext4_fsblk_t
2278 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2279 {
2280 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2281 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2282 }
2283 
2284 /*
2285  * Special error return code only used by dx_probe() and its callers.
2286  */
2287 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2288 
2289 /* htree levels for ext4 */
2290 #define	EXT4_HTREE_LEVEL_COMPAT	2
2291 #define	EXT4_HTREE_LEVEL	3
2292 
2293 static inline int ext4_dir_htree_level(struct super_block *sb)
2294 {
2295 	return ext4_has_feature_largedir(sb) ?
2296 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2297 }
2298 
2299 /*
2300  * Timeout and state flag for lazy initialization inode thread.
2301  */
2302 #define EXT4_DEF_LI_WAIT_MULT			10
2303 #define EXT4_DEF_LI_MAX_START_DELAY		5
2304 #define EXT4_LAZYINIT_QUIT			0x0001
2305 #define EXT4_LAZYINIT_RUNNING			0x0002
2306 
2307 /*
2308  * Lazy inode table initialization info
2309  */
2310 struct ext4_lazy_init {
2311 	unsigned long		li_state;
2312 	struct list_head	li_request_list;
2313 	struct mutex		li_list_mtx;
2314 };
2315 
2316 struct ext4_li_request {
2317 	struct super_block	*lr_super;
2318 	struct ext4_sb_info	*lr_sbi;
2319 	ext4_group_t		lr_next_group;
2320 	struct list_head	lr_request;
2321 	unsigned long		lr_next_sched;
2322 	unsigned long		lr_timeout;
2323 };
2324 
2325 struct ext4_features {
2326 	struct kobject f_kobj;
2327 	struct completion f_kobj_unregister;
2328 };
2329 
2330 /*
2331  * This structure will be used for multiple mount protection. It will be
2332  * written into the block number saved in the s_mmp_block field in the
2333  * superblock. Programs that check MMP should assume that if
2334  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2335  * to use the filesystem, regardless of how old the timestamp is.
2336  */
2337 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2338 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2339 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2340 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2341 
2342 struct mmp_struct {
2343 	__le32	mmp_magic;		/* Magic number for MMP */
2344 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2345 
2346 	/*
2347 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2348 	 * purposes and do not affect the correctness of the algorithm
2349 	 */
2350 	__le64	mmp_time;		/* Time last updated */
2351 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2352 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2353 
2354 	/*
2355 	 * mmp_check_interval is used to verify if the MMP block has been
2356 	 * updated on the block device. The value is updated based on the
2357 	 * maximum time to write the MMP block during an update cycle.
2358 	 */
2359 	__le16	mmp_check_interval;
2360 
2361 	__le16	mmp_pad1;
2362 	__le32	mmp_pad2[226];
2363 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2364 };
2365 
2366 /* arguments passed to the mmp thread */
2367 struct mmpd_data {
2368 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2369 	struct super_block *sb;  /* super block of the fs */
2370 };
2371 
2372 /*
2373  * Check interval multiplier
2374  * The MMP block is written every update interval and initially checked every
2375  * update interval x the multiplier (the value is then adapted based on the
2376  * write latency). The reason is that writes can be delayed under load and we
2377  * don't want readers to incorrectly assume that the filesystem is no longer
2378  * in use.
2379  */
2380 #define EXT4_MMP_CHECK_MULT		2UL
2381 
2382 /*
2383  * Minimum interval for MMP checking in seconds.
2384  */
2385 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2386 
2387 /*
2388  * Maximum interval for MMP checking in seconds.
2389  */
2390 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2391 
2392 /*
2393  * Function prototypes
2394  */
2395 
2396 /*
2397  * Ok, these declarations are also in <linux/kernel.h> but none of the
2398  * ext4 source programs needs to include it so they are duplicated here.
2399  */
2400 # define NORET_TYPE	/**/
2401 # define ATTRIB_NORET	__attribute__((noreturn))
2402 # define NORET_AND	noreturn,
2403 
2404 /* bitmap.c */
2405 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2406 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2407 				struct ext4_group_desc *gdp,
2408 				struct buffer_head *bh, int sz);
2409 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2410 				  struct ext4_group_desc *gdp,
2411 				  struct buffer_head *bh, int sz);
2412 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2413 				struct ext4_group_desc *gdp,
2414 				struct buffer_head *bh);
2415 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2416 				  struct ext4_group_desc *gdp,
2417 				  struct buffer_head *bh);
2418 
2419 /* balloc.c */
2420 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2421 					 ext4_fsblk_t blocknr,
2422 					 ext4_group_t *blockgrpp,
2423 					 ext4_grpblk_t *offsetp);
2424 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2425 					  ext4_fsblk_t block);
2426 
2427 extern unsigned int ext4_block_group(struct super_block *sb,
2428 			ext4_fsblk_t blocknr);
2429 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2430 			ext4_fsblk_t blocknr);
2431 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2432 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2433 			ext4_group_t group);
2434 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2435 					 ext4_fsblk_t goal,
2436 					 unsigned int flags,
2437 					 unsigned long *count,
2438 					 int *errp);
2439 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2440 				    s64 nclusters, unsigned int flags);
2441 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2442 extern void ext4_check_blocks_bitmap(struct super_block *);
2443 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2444 						    ext4_group_t block_group,
2445 						    struct buffer_head ** bh);
2446 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2447 
2448 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2449 						ext4_group_t block_group);
2450 extern int ext4_wait_block_bitmap(struct super_block *sb,
2451 				  ext4_group_t block_group,
2452 				  struct buffer_head *bh);
2453 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2454 						  ext4_group_t block_group);
2455 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2456 					      ext4_group_t block_group,
2457 					      struct ext4_group_desc *gdp);
2458 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2459 
2460 #ifdef CONFIG_UNICODE
2461 extern void ext4_fname_setup_ci_filename(struct inode *dir,
2462 					 const struct qstr *iname,
2463 					 struct fscrypt_str *fname);
2464 #endif
2465 
2466 #ifdef CONFIG_FS_ENCRYPTION
2467 static inline void ext4_fname_from_fscrypt_name(struct ext4_filename *dst,
2468 						const struct fscrypt_name *src)
2469 {
2470 	memset(dst, 0, sizeof(*dst));
2471 
2472 	dst->usr_fname = src->usr_fname;
2473 	dst->disk_name = src->disk_name;
2474 	dst->hinfo.hash = src->hash;
2475 	dst->hinfo.minor_hash = src->minor_hash;
2476 	dst->crypto_buf = src->crypto_buf;
2477 }
2478 
2479 static inline int ext4_fname_setup_filename(struct inode *dir,
2480 					    const struct qstr *iname,
2481 					    int lookup,
2482 					    struct ext4_filename *fname)
2483 {
2484 	struct fscrypt_name name;
2485 	int err;
2486 
2487 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2488 	if (err)
2489 		return err;
2490 
2491 	ext4_fname_from_fscrypt_name(fname, &name);
2492 
2493 #ifdef CONFIG_UNICODE
2494 	ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name);
2495 #endif
2496 	return 0;
2497 }
2498 
2499 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2500 					    struct dentry *dentry,
2501 					    struct ext4_filename *fname)
2502 {
2503 	struct fscrypt_name name;
2504 	int err;
2505 
2506 	err = fscrypt_prepare_lookup(dir, dentry, &name);
2507 	if (err)
2508 		return err;
2509 
2510 	ext4_fname_from_fscrypt_name(fname, &name);
2511 
2512 #ifdef CONFIG_UNICODE
2513 	ext4_fname_setup_ci_filename(dir, &dentry->d_name, &fname->cf_name);
2514 #endif
2515 	return 0;
2516 }
2517 
2518 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2519 {
2520 	struct fscrypt_name name;
2521 
2522 	name.crypto_buf = fname->crypto_buf;
2523 	fscrypt_free_filename(&name);
2524 
2525 	fname->crypto_buf.name = NULL;
2526 	fname->usr_fname = NULL;
2527 	fname->disk_name.name = NULL;
2528 
2529 #ifdef CONFIG_UNICODE
2530 	kfree(fname->cf_name.name);
2531 	fname->cf_name.name = NULL;
2532 #endif
2533 }
2534 #else /* !CONFIG_FS_ENCRYPTION */
2535 static inline int ext4_fname_setup_filename(struct inode *dir,
2536 					    const struct qstr *iname,
2537 					    int lookup,
2538 					    struct ext4_filename *fname)
2539 {
2540 	fname->usr_fname = iname;
2541 	fname->disk_name.name = (unsigned char *) iname->name;
2542 	fname->disk_name.len = iname->len;
2543 
2544 #ifdef CONFIG_UNICODE
2545 	ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name);
2546 #endif
2547 
2548 	return 0;
2549 }
2550 
2551 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2552 					    struct dentry *dentry,
2553 					    struct ext4_filename *fname)
2554 {
2555 	return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
2556 }
2557 
2558 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2559 {
2560 #ifdef CONFIG_UNICODE
2561 	kfree(fname->cf_name.name);
2562 	fname->cf_name.name = NULL;
2563 #endif
2564 }
2565 #endif /* !CONFIG_FS_ENCRYPTION */
2566 
2567 /* dir.c */
2568 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2569 				  struct file *,
2570 				  struct ext4_dir_entry_2 *,
2571 				  struct buffer_head *, char *, int,
2572 				  unsigned int);
2573 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2574 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2575 					(de), (bh), (buf), (size), (offset)))
2576 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2577 				__u32 minor_hash,
2578 				struct ext4_dir_entry_2 *dirent,
2579 				struct fscrypt_str *ent_name);
2580 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2581 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2582 			     struct buffer_head *bh,
2583 			     void *buf, int buf_size,
2584 			     struct ext4_filename *fname,
2585 			     struct ext4_dir_entry_2 **dest_de);
2586 void ext4_insert_dentry(struct inode *inode,
2587 			struct ext4_dir_entry_2 *de,
2588 			int buf_size,
2589 			struct ext4_filename *fname);
2590 static inline void ext4_update_dx_flag(struct inode *inode)
2591 {
2592 	if (!ext4_has_feature_dir_index(inode->i_sb)) {
2593 		/* ext4_iget() should have caught this... */
2594 		WARN_ON_ONCE(ext4_has_feature_metadata_csum(inode->i_sb));
2595 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2596 	}
2597 }
2598 static const unsigned char ext4_filetype_table[] = {
2599 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2600 };
2601 
2602 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2603 {
2604 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2605 		return DT_UNKNOWN;
2606 
2607 	return ext4_filetype_table[filetype];
2608 }
2609 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2610 			     void *buf, int buf_size);
2611 
2612 /* fsync.c */
2613 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2614 
2615 /* hash.c */
2616 extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
2617 			  struct dx_hash_info *hinfo);
2618 
2619 /* ialloc.c */
2620 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2621 				      const struct qstr *qstr, __u32 goal,
2622 				      uid_t *owner, __u32 i_flags,
2623 				      int handle_type, unsigned int line_no,
2624 				      int nblocks);
2625 
2626 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2627 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2628 			 i_flags, 0, 0, 0)
2629 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2630 				    type, nblocks)		    \
2631 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2632 			 0, (type), __LINE__, (nblocks))
2633 
2634 
2635 extern void ext4_free_inode(handle_t *, struct inode *);
2636 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2637 extern unsigned long ext4_count_free_inodes(struct super_block *);
2638 extern unsigned long ext4_count_dirs(struct super_block *);
2639 extern void ext4_check_inodes_bitmap(struct super_block *);
2640 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2641 extern int ext4_init_inode_table(struct super_block *sb,
2642 				 ext4_group_t group, int barrier);
2643 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2644 
2645 /* mballoc.c */
2646 extern const struct seq_operations ext4_mb_seq_groups_ops;
2647 extern long ext4_mb_stats;
2648 extern long ext4_mb_max_to_scan;
2649 extern int ext4_mb_init(struct super_block *);
2650 extern int ext4_mb_release(struct super_block *);
2651 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2652 				struct ext4_allocation_request *, int *);
2653 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2654 extern void ext4_discard_preallocations(struct inode *);
2655 extern int __init ext4_init_mballoc(void);
2656 extern void ext4_exit_mballoc(void);
2657 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2658 			     struct buffer_head *bh, ext4_fsblk_t block,
2659 			     unsigned long count, int flags);
2660 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2661 				   ext4_group_t ngroups);
2662 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2663 		ext4_group_t i, struct ext4_group_desc *desc);
2664 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2665 				ext4_fsblk_t block, unsigned long count);
2666 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2667 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2668 
2669 /* inode.c */
2670 int ext4_inode_is_fast_symlink(struct inode *inode);
2671 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2672 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2673 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2674 		     bool wait, struct buffer_head **bhs);
2675 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2676 			     struct buffer_head *bh_result, int create);
2677 int ext4_get_block(struct inode *inode, sector_t iblock,
2678 		   struct buffer_head *bh_result, int create);
2679 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2680 			   struct buffer_head *bh, int create);
2681 int ext4_walk_page_buffers(handle_t *handle,
2682 			   struct buffer_head *head,
2683 			   unsigned from,
2684 			   unsigned to,
2685 			   int *partial,
2686 			   int (*fn)(handle_t *handle,
2687 				     struct buffer_head *bh));
2688 int do_journal_get_write_access(handle_t *handle,
2689 				struct buffer_head *bh);
2690 #define FALL_BACK_TO_NONDELALLOC 1
2691 #define CONVERT_INLINE_DATA	 2
2692 
2693 typedef enum {
2694 	EXT4_IGET_NORMAL =	0,
2695 	EXT4_IGET_SPECIAL =	0x0001, /* OK to iget a system inode */
2696 	EXT4_IGET_HANDLE = 	0x0002	/* Inode # is from a handle */
2697 } ext4_iget_flags;
2698 
2699 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2700 				 ext4_iget_flags flags, const char *function,
2701 				 unsigned int line);
2702 
2703 #define ext4_iget(sb, ino, flags) \
2704 	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2705 
2706 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2707 extern int  ext4_setattr(struct dentry *, struct iattr *);
2708 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2709 extern void ext4_evict_inode(struct inode *);
2710 extern void ext4_clear_inode(struct inode *);
2711 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2712 extern int  ext4_sync_inode(handle_t *, struct inode *);
2713 extern void ext4_dirty_inode(struct inode *, int);
2714 extern int ext4_change_inode_journal_flag(struct inode *, int);
2715 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2716 extern int ext4_inode_attach_jinode(struct inode *inode);
2717 extern int ext4_can_truncate(struct inode *inode);
2718 extern int ext4_truncate(struct inode *);
2719 extern int ext4_break_layouts(struct inode *);
2720 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2721 extern void ext4_set_inode_flags(struct inode *, bool init);
2722 extern int ext4_alloc_da_blocks(struct inode *inode);
2723 extern void ext4_set_aops(struct inode *inode);
2724 extern int ext4_writepage_trans_blocks(struct inode *);
2725 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2726 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2727 			     loff_t lstart, loff_t lend);
2728 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
2729 extern vm_fault_t ext4_filemap_fault(struct vm_fault *vmf);
2730 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2731 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2732 extern void ext4_da_release_space(struct inode *inode, int to_free);
2733 extern void ext4_da_update_reserve_space(struct inode *inode,
2734 					int used, int quota_claim);
2735 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2736 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2737 
2738 /* indirect.c */
2739 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2740 				struct ext4_map_blocks *map, int flags);
2741 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2742 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2743 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2744 				 ext4_lblk_t start, ext4_lblk_t end);
2745 
2746 /* ioctl.c */
2747 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2748 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2749 
2750 /* migrate.c */
2751 extern int ext4_ext_migrate(struct inode *);
2752 extern int ext4_ind_migrate(struct inode *inode);
2753 
2754 /* namei.c */
2755 extern int ext4_dirblock_csum_verify(struct inode *inode,
2756 				     struct buffer_head *bh);
2757 extern int ext4_orphan_add(handle_t *, struct inode *);
2758 extern int ext4_orphan_del(handle_t *, struct inode *);
2759 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2760 				__u32 start_minor_hash, __u32 *next_hash);
2761 extern int ext4_search_dir(struct buffer_head *bh,
2762 			   char *search_buf,
2763 			   int buf_size,
2764 			   struct inode *dir,
2765 			   struct ext4_filename *fname,
2766 			   unsigned int offset,
2767 			   struct ext4_dir_entry_2 **res_dir);
2768 extern int ext4_generic_delete_entry(handle_t *handle,
2769 				     struct inode *dir,
2770 				     struct ext4_dir_entry_2 *de_del,
2771 				     struct buffer_head *bh,
2772 				     void *entry_buf,
2773 				     int buf_size,
2774 				     int csum_size);
2775 extern bool ext4_empty_dir(struct inode *inode);
2776 
2777 /* resize.c */
2778 extern void ext4_kvfree_array_rcu(void *to_free);
2779 extern int ext4_group_add(struct super_block *sb,
2780 				struct ext4_new_group_data *input);
2781 extern int ext4_group_extend(struct super_block *sb,
2782 				struct ext4_super_block *es,
2783 				ext4_fsblk_t n_blocks_count);
2784 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2785 
2786 /* super.c */
2787 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
2788 					 sector_t block, int op_flags);
2789 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2790 extern int ext4_calculate_overhead(struct super_block *sb);
2791 extern void ext4_superblock_csum_set(struct super_block *sb);
2792 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2793 				    ext4_group_t ngroup);
2794 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2795 				     char nbuf[16]);
2796 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
2797 					     ext4_group_t block_group,
2798 					     unsigned int flags);
2799 
2800 extern __printf(6, 7)
2801 void __ext4_error(struct super_block *, const char *, unsigned int, int, __u64,
2802 		  const char *, ...);
2803 extern __printf(6, 7)
2804 void __ext4_error_inode(struct inode *, const char *, unsigned int,
2805 			ext4_fsblk_t, int, const char *, ...);
2806 extern __printf(5, 6)
2807 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2808 		     const char *, ...);
2809 extern void __ext4_std_error(struct super_block *, const char *,
2810 			     unsigned int, int);
2811 extern __printf(5, 6)
2812 void __ext4_abort(struct super_block *, const char *, unsigned int, int,
2813 		  const char *, ...);
2814 extern __printf(4, 5)
2815 void __ext4_warning(struct super_block *, const char *, unsigned int,
2816 		    const char *, ...);
2817 extern __printf(4, 5)
2818 void __ext4_warning_inode(const struct inode *inode, const char *function,
2819 			  unsigned int line, const char *fmt, ...);
2820 extern __printf(3, 4)
2821 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2822 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2823 			   const char *, unsigned int, const char *);
2824 extern __printf(7, 8)
2825 void __ext4_grp_locked_error(const char *, unsigned int,
2826 			     struct super_block *, ext4_group_t,
2827 			     unsigned long, ext4_fsblk_t,
2828 			     const char *, ...);
2829 
2830 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2831 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2832 
2833 #define EXT4_ERROR_INODE_ERR(inode, err, fmt, a...)			\
2834 	__ext4_error_inode((inode), __func__, __LINE__, 0, (err), (fmt), ## a)
2835 
2836 #define ext4_error_inode_block(inode, block, err, fmt, a...)		\
2837 	__ext4_error_inode((inode), __func__, __LINE__, (block), (err),	\
2838 			   (fmt), ## a)
2839 
2840 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2841 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2842 
2843 #ifdef CONFIG_PRINTK
2844 
2845 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2846 	__ext4_error_inode(inode, func, line, block, 0, fmt, ##__VA_ARGS__)
2847 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
2848 	__ext4_error_inode((inode), (func), (line), (block), 		\
2849 			   (err), (fmt), ##__VA_ARGS__)
2850 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2851 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2852 #define ext4_error(sb, fmt, ...)					\
2853 	__ext4_error((sb), __func__, __LINE__, 0, 0, (fmt), ##__VA_ARGS__)
2854 #define ext4_error_err(sb, err, fmt, ...)				\
2855 	__ext4_error((sb), __func__, __LINE__, (err), 0, (fmt), ##__VA_ARGS__)
2856 #define ext4_abort(sb, err, fmt, ...)					\
2857 	__ext4_abort((sb), __func__, __LINE__, (err), (fmt), ##__VA_ARGS__)
2858 #define ext4_warning(sb, fmt, ...)					\
2859 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2860 #define ext4_warning_inode(inode, fmt, ...)				\
2861 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2862 #define ext4_msg(sb, level, fmt, ...)				\
2863 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2864 #define dump_mmp_msg(sb, mmp, msg)					\
2865 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2866 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2867 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2868 				fmt, ##__VA_ARGS__)
2869 
2870 #else
2871 
2872 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2873 do {									\
2874 	no_printk(fmt, ##__VA_ARGS__);					\
2875 	__ext4_error_inode(inode, "", 0, block, 0, " ");		\
2876 } while (0)
2877 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
2878 do {									\
2879 	no_printk(fmt, ##__VA_ARGS__);					\
2880 	__ext4_error_inode(inode, "", 0, block, err, " ");		\
2881 } while (0)
2882 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2883 do {									\
2884 	no_printk(fmt, ##__VA_ARGS__);					\
2885 	__ext4_error_file(file, "", 0, block, " ");			\
2886 } while (0)
2887 #define ext4_error(sb, fmt, ...)					\
2888 do {									\
2889 	no_printk(fmt, ##__VA_ARGS__);					\
2890 	__ext4_error(sb, "", 0, 0, 0, " ");				\
2891 } while (0)
2892 #define ext4_error_err(sb, err, fmt, ...)				\
2893 do {									\
2894 	no_printk(fmt, ##__VA_ARGS__);					\
2895 	__ext4_error(sb, "", 0, err, 0, " ");				\
2896 } while (0)
2897 #define ext4_abort(sb, err, fmt, ...)					\
2898 do {									\
2899 	no_printk(fmt, ##__VA_ARGS__);					\
2900 	__ext4_abort(sb, "", 0, err, " ");				\
2901 } while (0)
2902 #define ext4_warning(sb, fmt, ...)					\
2903 do {									\
2904 	no_printk(fmt, ##__VA_ARGS__);					\
2905 	__ext4_warning(sb, "", 0, " ");					\
2906 } while (0)
2907 #define ext4_warning_inode(inode, fmt, ...)				\
2908 do {									\
2909 	no_printk(fmt, ##__VA_ARGS__);					\
2910 	__ext4_warning_inode(inode, "", 0, " ");			\
2911 } while (0)
2912 #define ext4_msg(sb, level, fmt, ...)					\
2913 do {									\
2914 	no_printk(fmt, ##__VA_ARGS__);					\
2915 	__ext4_msg(sb, "", " ");					\
2916 } while (0)
2917 #define dump_mmp_msg(sb, mmp, msg)					\
2918 	__dump_mmp_msg(sb, mmp, "", 0, "")
2919 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2920 do {									\
2921 	no_printk(fmt, ##__VA_ARGS__);				\
2922 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2923 } while (0)
2924 
2925 #endif
2926 
2927 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2928 					__u32 compat);
2929 extern int ext4_update_rocompat_feature(handle_t *handle,
2930 					struct super_block *sb,	__u32 rocompat);
2931 extern int ext4_update_incompat_feature(handle_t *handle,
2932 					struct super_block *sb,	__u32 incompat);
2933 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2934 				      struct ext4_group_desc *bg);
2935 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2936 				      struct ext4_group_desc *bg);
2937 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2938 				     struct ext4_group_desc *bg);
2939 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2940 				      struct ext4_group_desc *bg);
2941 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2942 				 struct ext4_group_desc *bg);
2943 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2944 				struct ext4_group_desc *bg);
2945 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2946 				   struct ext4_group_desc *bg);
2947 extern void ext4_block_bitmap_set(struct super_block *sb,
2948 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2949 extern void ext4_inode_bitmap_set(struct super_block *sb,
2950 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2951 extern void ext4_inode_table_set(struct super_block *sb,
2952 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2953 extern void ext4_free_group_clusters_set(struct super_block *sb,
2954 					 struct ext4_group_desc *bg,
2955 					 __u32 count);
2956 extern void ext4_free_inodes_set(struct super_block *sb,
2957 				struct ext4_group_desc *bg, __u32 count);
2958 extern void ext4_used_dirs_set(struct super_block *sb,
2959 				struct ext4_group_desc *bg, __u32 count);
2960 extern void ext4_itable_unused_set(struct super_block *sb,
2961 				   struct ext4_group_desc *bg, __u32 count);
2962 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2963 				       struct ext4_group_desc *gdp);
2964 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2965 				     struct ext4_group_desc *gdp);
2966 extern int ext4_register_li_request(struct super_block *sb,
2967 				    ext4_group_t first_not_zeroed);
2968 
2969 static inline int ext4_has_metadata_csum(struct super_block *sb)
2970 {
2971 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2972 		     !EXT4_SB(sb)->s_chksum_driver);
2973 
2974 	return ext4_has_feature_metadata_csum(sb) &&
2975 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
2976 }
2977 
2978 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2979 {
2980 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
2981 }
2982 
2983 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2984 {
2985 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2986 		le32_to_cpu(es->s_blocks_count_lo);
2987 }
2988 
2989 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2990 {
2991 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2992 		le32_to_cpu(es->s_r_blocks_count_lo);
2993 }
2994 
2995 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2996 {
2997 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2998 		le32_to_cpu(es->s_free_blocks_count_lo);
2999 }
3000 
3001 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
3002 					 ext4_fsblk_t blk)
3003 {
3004 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
3005 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
3006 }
3007 
3008 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
3009 					      ext4_fsblk_t blk)
3010 {
3011 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
3012 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
3013 }
3014 
3015 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
3016 					   ext4_fsblk_t blk)
3017 {
3018 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
3019 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
3020 }
3021 
3022 static inline loff_t ext4_isize(struct super_block *sb,
3023 				struct ext4_inode *raw_inode)
3024 {
3025 	if (ext4_has_feature_largedir(sb) ||
3026 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
3027 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
3028 			le32_to_cpu(raw_inode->i_size_lo);
3029 
3030 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
3031 }
3032 
3033 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
3034 {
3035 	raw_inode->i_size_lo = cpu_to_le32(i_size);
3036 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
3037 }
3038 
3039 static inline
3040 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
3041 					    ext4_group_t group)
3042 {
3043 	 struct ext4_group_info **grp_info;
3044 	 long indexv, indexh;
3045 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
3046 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
3047 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
3048 	 grp_info = sbi_array_rcu_deref(EXT4_SB(sb), s_group_info, indexv);
3049 	 return grp_info[indexh];
3050 }
3051 
3052 /*
3053  * Reading s_groups_count requires using smp_rmb() afterwards.  See
3054  * the locking protocol documented in the comments of ext4_group_add()
3055  * in resize.c
3056  */
3057 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
3058 {
3059 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
3060 
3061 	smp_rmb();
3062 	return ngroups;
3063 }
3064 
3065 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
3066 					     ext4_group_t block_group)
3067 {
3068 	return block_group >> sbi->s_log_groups_per_flex;
3069 }
3070 
3071 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
3072 {
3073 	return 1 << sbi->s_log_groups_per_flex;
3074 }
3075 
3076 #define ext4_std_error(sb, errno)				\
3077 do {								\
3078 	if ((errno))						\
3079 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
3080 } while (0)
3081 
3082 #ifdef CONFIG_SMP
3083 /* Each CPU can accumulate percpu_counter_batch clusters in their local
3084  * counters. So we need to make sure we have free clusters more
3085  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
3086  */
3087 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
3088 #else
3089 #define EXT4_FREECLUSTERS_WATERMARK 0
3090 #endif
3091 
3092 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
3093 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
3094 {
3095 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
3096 		     !inode_is_locked(inode));
3097 	down_write(&EXT4_I(inode)->i_data_sem);
3098 	if (newsize > EXT4_I(inode)->i_disksize)
3099 		WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
3100 	up_write(&EXT4_I(inode)->i_data_sem);
3101 }
3102 
3103 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
3104 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
3105 {
3106 	int changed = 0;
3107 
3108 	if (newsize > inode->i_size) {
3109 		i_size_write(inode, newsize);
3110 		changed = 1;
3111 	}
3112 	if (newsize > EXT4_I(inode)->i_disksize) {
3113 		ext4_update_i_disksize(inode, newsize);
3114 		changed |= 2;
3115 	}
3116 	return changed;
3117 }
3118 
3119 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
3120 				      loff_t len);
3121 
3122 struct ext4_group_info {
3123 	unsigned long   bb_state;
3124 	struct rb_root  bb_free_root;
3125 	ext4_grpblk_t	bb_first_free;	/* first free block */
3126 	ext4_grpblk_t	bb_free;	/* total free blocks */
3127 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
3128 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
3129 	struct          list_head bb_prealloc_list;
3130 #ifdef DOUBLE_CHECK
3131 	void            *bb_bitmap;
3132 #endif
3133 	struct rw_semaphore alloc_sem;
3134 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
3135 					 * regions, index is order.
3136 					 * bb_counters[3] = 5 means
3137 					 * 5 free 8-block regions. */
3138 };
3139 
3140 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
3141 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
3142 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
3143 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
3144 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT		\
3145 	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
3146 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT		\
3147 	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
3148 
3149 #define EXT4_MB_GRP_NEED_INIT(grp)	\
3150 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
3151 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
3152 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3153 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
3154 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3155 
3156 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
3157 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3158 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
3159 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3160 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
3161 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3162 
3163 #define EXT4_MAX_CONTENTION		8
3164 #define EXT4_CONTENTION_THRESHOLD	2
3165 
3166 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
3167 					      ext4_group_t group)
3168 {
3169 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
3170 }
3171 
3172 /*
3173  * Returns true if the filesystem is busy enough that attempts to
3174  * access the block group locks has run into contention.
3175  */
3176 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
3177 {
3178 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
3179 }
3180 
3181 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
3182 {
3183 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
3184 	if (spin_trylock(lock))
3185 		/*
3186 		 * We're able to grab the lock right away, so drop the
3187 		 * lock contention counter.
3188 		 */
3189 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
3190 	else {
3191 		/*
3192 		 * The lock is busy, so bump the contention counter,
3193 		 * and then wait on the spin lock.
3194 		 */
3195 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
3196 				  EXT4_MAX_CONTENTION);
3197 		spin_lock(lock);
3198 	}
3199 }
3200 
3201 static inline void ext4_unlock_group(struct super_block *sb,
3202 					ext4_group_t group)
3203 {
3204 	spin_unlock(ext4_group_lock_ptr(sb, group));
3205 }
3206 
3207 /*
3208  * Block validity checking
3209  */
3210 #define ext4_check_indirect_blockref(inode, bh)				\
3211 	ext4_check_blockref(__func__, __LINE__, inode,			\
3212 			    (__le32 *)(bh)->b_data,			\
3213 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3214 
3215 #define ext4_ind_check_inode(inode)					\
3216 	ext4_check_blockref(__func__, __LINE__, inode,			\
3217 			    EXT4_I(inode)->i_data,			\
3218 			    EXT4_NDIR_BLOCKS)
3219 
3220 /*
3221  * Inodes and files operations
3222  */
3223 
3224 /* dir.c */
3225 extern const struct file_operations ext4_dir_operations;
3226 
3227 #ifdef CONFIG_UNICODE
3228 extern const struct dentry_operations ext4_dentry_ops;
3229 #endif
3230 
3231 /* file.c */
3232 extern const struct inode_operations ext4_file_inode_operations;
3233 extern const struct file_operations ext4_file_operations;
3234 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
3235 
3236 /* inline.c */
3237 extern int ext4_get_max_inline_size(struct inode *inode);
3238 extern int ext4_find_inline_data_nolock(struct inode *inode);
3239 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
3240 				 unsigned int len);
3241 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3242 
3243 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
3244 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3245 					 struct inode *inode,
3246 					 loff_t pos, unsigned len,
3247 					 unsigned flags,
3248 					 struct page **pagep);
3249 extern int ext4_write_inline_data_end(struct inode *inode,
3250 				      loff_t pos, unsigned len,
3251 				      unsigned copied,
3252 				      struct page *page);
3253 extern struct buffer_head *
3254 ext4_journalled_write_inline_data(struct inode *inode,
3255 				  unsigned len,
3256 				  struct page *page);
3257 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3258 					   struct inode *inode,
3259 					   loff_t pos, unsigned len,
3260 					   unsigned flags,
3261 					   struct page **pagep,
3262 					   void **fsdata);
3263 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3264 					 unsigned len, unsigned copied,
3265 					 struct page *page);
3266 extern int ext4_try_add_inline_entry(handle_t *handle,
3267 				     struct ext4_filename *fname,
3268 				     struct inode *dir, struct inode *inode);
3269 extern int ext4_try_create_inline_dir(handle_t *handle,
3270 				      struct inode *parent,
3271 				      struct inode *inode);
3272 extern int ext4_read_inline_dir(struct file *filp,
3273 				struct dir_context *ctx,
3274 				int *has_inline_data);
3275 extern int ext4_inlinedir_to_tree(struct file *dir_file,
3276 				  struct inode *dir, ext4_lblk_t block,
3277 				  struct dx_hash_info *hinfo,
3278 				  __u32 start_hash, __u32 start_minor_hash,
3279 				  int *has_inline_data);
3280 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3281 					struct ext4_filename *fname,
3282 					struct ext4_dir_entry_2 **res_dir,
3283 					int *has_inline_data);
3284 extern int ext4_delete_inline_entry(handle_t *handle,
3285 				    struct inode *dir,
3286 				    struct ext4_dir_entry_2 *de_del,
3287 				    struct buffer_head *bh,
3288 				    int *has_inline_data);
3289 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3290 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3291 					struct ext4_dir_entry_2 **parent_de,
3292 					int *retval);
3293 extern int ext4_inline_data_fiemap(struct inode *inode,
3294 				   struct fiemap_extent_info *fieinfo,
3295 				   int *has_inline, __u64 start, __u64 len);
3296 
3297 struct iomap;
3298 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3299 
3300 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3301 
3302 extern int ext4_convert_inline_data(struct inode *inode);
3303 
3304 static inline int ext4_has_inline_data(struct inode *inode)
3305 {
3306 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3307 	       EXT4_I(inode)->i_inline_off;
3308 }
3309 
3310 /* namei.c */
3311 extern const struct inode_operations ext4_dir_inode_operations;
3312 extern const struct inode_operations ext4_special_inode_operations;
3313 extern struct dentry *ext4_get_parent(struct dentry *child);
3314 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3315 				 struct ext4_dir_entry_2 *de,
3316 				 int blocksize, int csum_size,
3317 				 unsigned int parent_ino, int dotdot_real_len);
3318 extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
3319 					unsigned int blocksize);
3320 extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
3321 				      struct buffer_head *bh);
3322 extern int ext4_ci_compare(const struct inode *parent,
3323 			   const struct qstr *fname,
3324 			   const struct qstr *entry, bool quick);
3325 
3326 #define S_SHIFT 12
3327 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3328 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3329 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3330 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3331 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3332 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3333 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3334 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3335 };
3336 
3337 static inline void ext4_set_de_type(struct super_block *sb,
3338 				struct ext4_dir_entry_2 *de,
3339 				umode_t mode) {
3340 	if (ext4_has_feature_filetype(sb))
3341 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3342 }
3343 
3344 /* readpages.c */
3345 extern int ext4_mpage_readpages(struct inode *inode,
3346 		struct readahead_control *rac, struct page *page);
3347 extern int __init ext4_init_post_read_processing(void);
3348 extern void ext4_exit_post_read_processing(void);
3349 
3350 /* symlink.c */
3351 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3352 extern const struct inode_operations ext4_symlink_inode_operations;
3353 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3354 
3355 /* sysfs.c */
3356 extern int ext4_register_sysfs(struct super_block *sb);
3357 extern void ext4_unregister_sysfs(struct super_block *sb);
3358 extern int __init ext4_init_sysfs(void);
3359 extern void ext4_exit_sysfs(void);
3360 
3361 /* block_validity */
3362 extern void ext4_release_system_zone(struct super_block *sb);
3363 extern int ext4_setup_system_zone(struct super_block *sb);
3364 extern int __init ext4_init_system_zone(void);
3365 extern void ext4_exit_system_zone(void);
3366 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3367 				 ext4_fsblk_t start_blk,
3368 				 unsigned int count);
3369 extern int ext4_check_blockref(const char *, unsigned int,
3370 			       struct inode *, __le32 *, unsigned int);
3371 
3372 /* extents.c */
3373 struct ext4_ext_path;
3374 struct ext4_extent;
3375 
3376 /*
3377  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3378  * __le32.
3379  */
3380 #define EXT_MAX_BLOCKS	0xffffffff
3381 
3382 extern void ext4_ext_tree_init(handle_t *handle, struct inode *inode);
3383 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3384 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3385 			       struct ext4_map_blocks *map, int flags);
3386 extern int ext4_ext_truncate(handle_t *, struct inode *);
3387 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3388 				 ext4_lblk_t end);
3389 extern void ext4_ext_init(struct super_block *);
3390 extern void ext4_ext_release(struct super_block *);
3391 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3392 			  loff_t len);
3393 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3394 					  loff_t offset, ssize_t len);
3395 extern int ext4_convert_unwritten_io_end_vec(handle_t *handle,
3396 					     ext4_io_end_t *io_end);
3397 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3398 			   struct ext4_map_blocks *map, int flags);
3399 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3400 						   int num,
3401 						   struct ext4_ext_path *path);
3402 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3403 				  struct ext4_ext_path **,
3404 				  struct ext4_extent *, int);
3405 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3406 					      struct ext4_ext_path **,
3407 					      int flags);
3408 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3409 extern int ext4_ext_check_inode(struct inode *inode);
3410 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3411 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3412 			__u64 start, __u64 len);
3413 extern int ext4_get_es_cache(struct inode *inode,
3414 			     struct fiemap_extent_info *fieinfo,
3415 			     __u64 start, __u64 len);
3416 extern int ext4_ext_precache(struct inode *inode);
3417 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3418 				struct inode *inode2, ext4_lblk_t lblk1,
3419 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3420 			     int mark_unwritten,int *err);
3421 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3422 extern int ext4_datasem_ensure_credits(handle_t *handle, struct inode *inode,
3423 				       int check_cred, int restart_cred,
3424 				       int revoke_cred);
3425 
3426 
3427 /* move_extent.c */
3428 extern void ext4_double_down_write_data_sem(struct inode *first,
3429 					    struct inode *second);
3430 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3431 					  struct inode *donor_inode);
3432 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3433 			     __u64 start_orig, __u64 start_donor,
3434 			     __u64 len, __u64 *moved_len);
3435 
3436 /* page-io.c */
3437 extern int __init ext4_init_pageio(void);
3438 extern void ext4_exit_pageio(void);
3439 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3440 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3441 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3442 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3443 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3444 				struct writeback_control *wbc);
3445 extern void ext4_end_io_rsv_work(struct work_struct *work);
3446 extern void ext4_io_submit(struct ext4_io_submit *io);
3447 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3448 			       struct page *page,
3449 			       int len,
3450 			       struct writeback_control *wbc,
3451 			       bool keep_towrite);
3452 extern struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end);
3453 extern struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end);
3454 
3455 /* mmp.c */
3456 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3457 
3458 /* verity.c */
3459 extern const struct fsverity_operations ext4_verityops;
3460 
3461 /*
3462  * Add new method to test whether block and inode bitmaps are properly
3463  * initialized. With uninit_bg reading the block from disk is not enough
3464  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3465  */
3466 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3467 
3468 static inline int bitmap_uptodate(struct buffer_head *bh)
3469 {
3470 	return (buffer_uptodate(bh) &&
3471 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3472 }
3473 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3474 {
3475 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3476 }
3477 
3478 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3479 
3480 /* For ioend & aio unwritten conversion wait queues */
3481 #define EXT4_WQ_HASH_SZ		37
3482 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3483 					    EXT4_WQ_HASH_SZ])
3484 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3485 
3486 extern int ext4_resize_begin(struct super_block *sb);
3487 extern void ext4_resize_end(struct super_block *sb);
3488 
3489 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3490 					      struct ext4_io_end *io_end)
3491 {
3492 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3493 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3494 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3495 	}
3496 }
3497 
3498 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3499 {
3500 	struct inode *inode = io_end->inode;
3501 
3502 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3503 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3504 		/* Wake up anyone waiting on unwritten extent conversion */
3505 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3506 			wake_up_all(ext4_ioend_wq(inode));
3507 	}
3508 }
3509 
3510 extern const struct iomap_ops ext4_iomap_ops;
3511 extern const struct iomap_ops ext4_iomap_overwrite_ops;
3512 extern const struct iomap_ops ext4_iomap_report_ops;
3513 
3514 static inline int ext4_buffer_uptodate(struct buffer_head *bh)
3515 {
3516 	/*
3517 	 * If the buffer has the write error flag, we have failed
3518 	 * to write out data in the block.  In this  case, we don't
3519 	 * have to read the block because we may read the old data
3520 	 * successfully.
3521 	 */
3522 	if (!buffer_uptodate(bh) && buffer_write_io_error(bh))
3523 		set_buffer_uptodate(bh);
3524 	return buffer_uptodate(bh);
3525 }
3526 
3527 #endif	/* __KERNEL__ */
3528 
3529 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3530 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3531 
3532 #endif	/* _EXT4_H */
3533