xref: /openbmc/linux/fs/ext4/ext4.h (revision d5a05299)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  ext4.h
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/include/linux/minix_fs.h
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  */
16 
17 #ifndef _EXT4_H
18 #define _EXT4_H
19 
20 #include <linux/refcount.h>
21 #include <linux/types.h>
22 #include <linux/blkdev.h>
23 #include <linux/magic.h>
24 #include <linux/jbd2.h>
25 #include <linux/quota.h>
26 #include <linux/rwsem.h>
27 #include <linux/rbtree.h>
28 #include <linux/seqlock.h>
29 #include <linux/mutex.h>
30 #include <linux/timer.h>
31 #include <linux/wait.h>
32 #include <linux/sched/signal.h>
33 #include <linux/blockgroup_lock.h>
34 #include <linux/percpu_counter.h>
35 #include <linux/ratelimit.h>
36 #include <crypto/hash.h>
37 #include <linux/falloc.h>
38 #include <linux/percpu-rwsem.h>
39 #include <linux/fiemap.h>
40 #ifdef __KERNEL__
41 #include <linux/compat.h>
42 #endif
43 #include <uapi/linux/ext4.h>
44 
45 #include <linux/fscrypt.h>
46 #include <linux/fsverity.h>
47 
48 #include <linux/compiler.h>
49 
50 /*
51  * The fourth extended filesystem constants/structures
52  */
53 
54 /*
55  * with AGGRESSIVE_CHECK allocator runs consistency checks over
56  * structures. these checks slow things down a lot
57  */
58 #define AGGRESSIVE_CHECK__
59 
60 /*
61  * with DOUBLE_CHECK defined mballoc creates persistent in-core
62  * bitmaps, maintains and uses them to check for double allocations
63  */
64 #define DOUBLE_CHECK__
65 
66 /*
67  * Define EXT4FS_DEBUG to produce debug messages
68  */
69 #undef EXT4FS_DEBUG
70 
71 /*
72  * Debug code
73  */
74 #ifdef EXT4FS_DEBUG
75 #define ext4_debug(f, a...)						\
76 	do {								\
77 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
78 			__FILE__, __LINE__, __func__);			\
79 		printk(KERN_DEBUG f, ## a);				\
80 	} while (0)
81 #else
82 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
83 #endif
84 
85  /*
86   * Turn on EXT_DEBUG to enable ext4_ext_show_path/leaf/move in extents.c
87   */
88 #define EXT_DEBUG__
89 
90 /*
91  * Dynamic printk for controlled extents debugging.
92  */
93 #ifdef CONFIG_EXT4_DEBUG
94 #define ext_debug(ino, fmt, ...)					\
95 	pr_debug("[%s/%d] EXT4-fs (%s): ino %lu: (%s, %d): %s:" fmt,	\
96 		 current->comm, task_pid_nr(current),			\
97 		 ino->i_sb->s_id, ino->i_ino, __FILE__, __LINE__,	\
98 		 __func__, ##__VA_ARGS__)
99 #else
100 #define ext_debug(ino, fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
101 #endif
102 
103 #define ASSERT(assert)						\
104 do {									\
105 	if (unlikely(!(assert))) {					\
106 		printk(KERN_EMERG					\
107 		       "Assertion failure in %s() at %s:%d: '%s'\n",	\
108 		       __func__, __FILE__, __LINE__, #assert);		\
109 		BUG();							\
110 	}								\
111 } while (0)
112 
113 /* data type for block offset of block group */
114 typedef int ext4_grpblk_t;
115 
116 /* data type for filesystem-wide blocks number */
117 typedef unsigned long long ext4_fsblk_t;
118 
119 /* data type for file logical block number */
120 typedef __u32 ext4_lblk_t;
121 
122 /* data type for block group number */
123 typedef unsigned int ext4_group_t;
124 
125 enum SHIFT_DIRECTION {
126 	SHIFT_LEFT = 0,
127 	SHIFT_RIGHT,
128 };
129 
130 /*
131  * Flags used in mballoc's allocation_context flags field.
132  *
133  * Also used to show what's going on for debugging purposes when the
134  * flag field is exported via the traceport interface
135  */
136 
137 /* prefer goal again. length */
138 #define EXT4_MB_HINT_MERGE		0x0001
139 /* blocks already reserved */
140 #define EXT4_MB_HINT_RESERVED		0x0002
141 /* metadata is being allocated */
142 #define EXT4_MB_HINT_METADATA		0x0004
143 /* first blocks in the file */
144 #define EXT4_MB_HINT_FIRST		0x0008
145 /* search for the best chunk */
146 #define EXT4_MB_HINT_BEST		0x0010
147 /* data is being allocated */
148 #define EXT4_MB_HINT_DATA		0x0020
149 /* don't preallocate (for tails) */
150 #define EXT4_MB_HINT_NOPREALLOC		0x0040
151 /* allocate for locality group */
152 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
153 /* allocate goal blocks or none */
154 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
155 /* goal is meaningful */
156 #define EXT4_MB_HINT_TRY_GOAL		0x0200
157 /* blocks already pre-reserved by delayed allocation */
158 #define EXT4_MB_DELALLOC_RESERVED	0x0400
159 /* We are doing stream allocation */
160 #define EXT4_MB_STREAM_ALLOC		0x0800
161 /* Use reserved root blocks if needed */
162 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
163 /* Use blocks from reserved pool */
164 #define EXT4_MB_USE_RESERVED		0x2000
165 /* Do strict check for free blocks while retrying block allocation */
166 #define EXT4_MB_STRICT_CHECK		0x4000
167 /* Large fragment size list lookup succeeded at least once for cr = 0 */
168 #define EXT4_MB_CR0_OPTIMIZED		0x8000
169 /* Avg fragment size rb tree lookup succeeded at least once for cr = 1 */
170 #define EXT4_MB_CR1_OPTIMIZED		0x00010000
171 struct ext4_allocation_request {
172 	/* target inode for block we're allocating */
173 	struct inode *inode;
174 	/* how many blocks we want to allocate */
175 	unsigned int len;
176 	/* logical block in target inode */
177 	ext4_lblk_t logical;
178 	/* the closest logical allocated block to the left */
179 	ext4_lblk_t lleft;
180 	/* the closest logical allocated block to the right */
181 	ext4_lblk_t lright;
182 	/* phys. target (a hint) */
183 	ext4_fsblk_t goal;
184 	/* phys. block for the closest logical allocated block to the left */
185 	ext4_fsblk_t pleft;
186 	/* phys. block for the closest logical allocated block to the right */
187 	ext4_fsblk_t pright;
188 	/* flags. see above EXT4_MB_HINT_* */
189 	unsigned int flags;
190 };
191 
192 /*
193  * Logical to physical block mapping, used by ext4_map_blocks()
194  *
195  * This structure is used to pass requests into ext4_map_blocks() as
196  * well as to store the information returned by ext4_map_blocks().  It
197  * takes less room on the stack than a struct buffer_head.
198  */
199 #define EXT4_MAP_NEW		BIT(BH_New)
200 #define EXT4_MAP_MAPPED		BIT(BH_Mapped)
201 #define EXT4_MAP_UNWRITTEN	BIT(BH_Unwritten)
202 #define EXT4_MAP_BOUNDARY	BIT(BH_Boundary)
203 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
204 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
205 
206 struct ext4_map_blocks {
207 	ext4_fsblk_t m_pblk;
208 	ext4_lblk_t m_lblk;
209 	unsigned int m_len;
210 	unsigned int m_flags;
211 };
212 
213 /*
214  * Block validity checking, system zone rbtree.
215  */
216 struct ext4_system_blocks {
217 	struct rb_root root;
218 	struct rcu_head rcu;
219 };
220 
221 /*
222  * Flags for ext4_io_end->flags
223  */
224 #define	EXT4_IO_END_UNWRITTEN	0x0001
225 
226 struct ext4_io_end_vec {
227 	struct list_head list;		/* list of io_end_vec */
228 	loff_t offset;			/* offset in the file */
229 	ssize_t size;			/* size of the extent */
230 };
231 
232 /*
233  * For converting unwritten extents on a work queue. 'handle' is used for
234  * buffered writeback.
235  */
236 typedef struct ext4_io_end {
237 	struct list_head	list;		/* per-file finished IO list */
238 	handle_t		*handle;	/* handle reserved for extent
239 						 * conversion */
240 	struct inode		*inode;		/* file being written to */
241 	struct bio		*bio;		/* Linked list of completed
242 						 * bios covering the extent */
243 	unsigned int		flag;		/* unwritten or not */
244 	refcount_t		count;		/* reference counter */
245 	struct list_head	list_vec;	/* list of ext4_io_end_vec */
246 } ext4_io_end_t;
247 
248 struct ext4_io_submit {
249 	struct writeback_control *io_wbc;
250 	struct bio		*io_bio;
251 	ext4_io_end_t		*io_end;
252 	sector_t		io_next_block;
253 };
254 
255 /*
256  * Special inodes numbers
257  */
258 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
259 #define EXT4_ROOT_INO		 2	/* Root inode */
260 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
261 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
262 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
263 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
264 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
265 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
266 
267 /* First non-reserved inode for old ext4 filesystems */
268 #define EXT4_GOOD_OLD_FIRST_INO	11
269 
270 /*
271  * Maximal count of links to a file
272  */
273 #define EXT4_LINK_MAX		65000
274 
275 /*
276  * Macro-instructions used to manage several block sizes
277  */
278 #define EXT4_MIN_BLOCK_SIZE		1024
279 #define	EXT4_MAX_BLOCK_SIZE		65536
280 #define EXT4_MIN_BLOCK_LOG_SIZE		10
281 #define EXT4_MAX_BLOCK_LOG_SIZE		16
282 #define EXT4_MAX_CLUSTER_LOG_SIZE	30
283 #ifdef __KERNEL__
284 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
285 #else
286 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
287 #endif
288 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
289 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
290 					 EXT4_SB(s)->s_cluster_bits)
291 #ifdef __KERNEL__
292 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
293 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
294 #else
295 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
296 #endif
297 #ifdef __KERNEL__
298 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
299 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
300 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
301 #else
302 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
303 				 EXT4_GOOD_OLD_INODE_SIZE : \
304 				 (s)->s_inode_size)
305 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
306 				 EXT4_GOOD_OLD_FIRST_INO : \
307 				 (s)->s_first_ino)
308 #endif
309 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
310 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
311 	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
312 								  blkbits))
313 
314 /* Translate a block number to a cluster number */
315 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
316 /* Translate a cluster number to a block number */
317 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
318 /* Translate # of blks to # of clusters */
319 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
320 				 (sbi)->s_cluster_bits)
321 /* Mask out the low bits to get the starting block of the cluster */
322 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
323 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
324 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
325 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
326 /* Fill in the low bits to get the last block of the cluster */
327 #define EXT4_LBLK_CFILL(sbi, lblk) ((lblk) |				\
328 				    ((ext4_lblk_t) (sbi)->s_cluster_ratio - 1))
329 /* Get the cluster offset */
330 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
331 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
332 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
333 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
334 
335 /*
336  * Structure of a blocks group descriptor
337  */
338 struct ext4_group_desc
339 {
340 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
341 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
342 	__le32	bg_inode_table_lo;	/* Inodes table block */
343 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
344 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
345 	__le16	bg_used_dirs_count_lo;	/* Directories count */
346 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
347 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
348 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
349 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
350 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
351 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
352 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
353 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
354 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
355 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
356 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
357 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
358 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
359 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
360 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
361 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
362 	__u32   bg_reserved;
363 };
364 
365 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
366 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
367 	 sizeof(__le16))
368 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
369 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
370 	 sizeof(__le16))
371 
372 /*
373  * Structure of a flex block group info
374  */
375 
376 struct flex_groups {
377 	atomic64_t	free_clusters;
378 	atomic_t	free_inodes;
379 	atomic_t	used_dirs;
380 };
381 
382 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
383 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
384 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
385 
386 /*
387  * Macro-instructions used to manage group descriptors
388  */
389 #define EXT4_MIN_DESC_SIZE		32
390 #define EXT4_MIN_DESC_SIZE_64BIT	64
391 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
392 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
393 #ifdef __KERNEL__
394 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
395 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
396 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
397 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
398 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
399 #else
400 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
401 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
402 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
403 #endif
404 
405 /*
406  * Constants relative to the data blocks
407  */
408 #define	EXT4_NDIR_BLOCKS		12
409 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
410 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
411 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
412 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
413 
414 /*
415  * Inode flags
416  */
417 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
418 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
419 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
420 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
421 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
422 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
423 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
424 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
425 /* Reserved for compression usage... */
426 #define EXT4_DIRTY_FL			0x00000100
427 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
428 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
429 	/* nb: was previously EXT2_ECOMPR_FL */
430 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
431 /* End compression flags --- maybe not all used */
432 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
433 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
434 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
435 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
436 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
437 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
438 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
439 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
440 #define EXT4_VERITY_FL			0x00100000 /* Verity protected inode */
441 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
442 /* 0x00400000 was formerly EXT4_EOFBLOCKS_FL */
443 
444 #define EXT4_DAX_FL			0x02000000 /* Inode is DAX */
445 
446 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
447 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
448 #define EXT4_CASEFOLD_FL		0x40000000 /* Casefolded directory */
449 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
450 
451 /* User modifiable flags */
452 #define EXT4_FL_USER_MODIFIABLE		(EXT4_SECRM_FL | \
453 					 EXT4_UNRM_FL | \
454 					 EXT4_COMPR_FL | \
455 					 EXT4_SYNC_FL | \
456 					 EXT4_IMMUTABLE_FL | \
457 					 EXT4_APPEND_FL | \
458 					 EXT4_NODUMP_FL | \
459 					 EXT4_NOATIME_FL | \
460 					 EXT4_JOURNAL_DATA_FL | \
461 					 EXT4_NOTAIL_FL | \
462 					 EXT4_DIRSYNC_FL | \
463 					 EXT4_TOPDIR_FL | \
464 					 EXT4_EXTENTS_FL | \
465 					 0x00400000 /* EXT4_EOFBLOCKS_FL */ | \
466 					 EXT4_DAX_FL | \
467 					 EXT4_PROJINHERIT_FL | \
468 					 EXT4_CASEFOLD_FL)
469 
470 /* User visible flags */
471 #define EXT4_FL_USER_VISIBLE		(EXT4_FL_USER_MODIFIABLE | \
472 					 EXT4_DIRTY_FL | \
473 					 EXT4_COMPRBLK_FL | \
474 					 EXT4_NOCOMPR_FL | \
475 					 EXT4_ENCRYPT_FL | \
476 					 EXT4_INDEX_FL | \
477 					 EXT4_VERITY_FL | \
478 					 EXT4_INLINE_DATA_FL)
479 
480 /* Flags that should be inherited by new inodes from their parent. */
481 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
482 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
483 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
484 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
485 			   EXT4_PROJINHERIT_FL | EXT4_CASEFOLD_FL |\
486 			   EXT4_DAX_FL)
487 
488 /* Flags that are appropriate for regular files (all but dir-specific ones). */
489 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL | EXT4_CASEFOLD_FL |\
490 			   EXT4_PROJINHERIT_FL))
491 
492 /* Flags that are appropriate for non-directories/regular files. */
493 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
494 
495 /* The only flags that should be swapped */
496 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
497 
498 /* Flags which are mutually exclusive to DAX */
499 #define EXT4_DAX_MUT_EXCL (EXT4_VERITY_FL | EXT4_ENCRYPT_FL |\
500 			   EXT4_JOURNAL_DATA_FL | EXT4_INLINE_DATA_FL)
501 
502 /* Mask out flags that are inappropriate for the given type of inode. */
503 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
504 {
505 	if (S_ISDIR(mode))
506 		return flags;
507 	else if (S_ISREG(mode))
508 		return flags & EXT4_REG_FLMASK;
509 	else
510 		return flags & EXT4_OTHER_FLMASK;
511 }
512 
513 /*
514  * Inode flags used for atomic set/get
515  */
516 enum {
517 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
518 	EXT4_INODE_UNRM		= 1,	/* Undelete */
519 	EXT4_INODE_COMPR	= 2,	/* Compress file */
520 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
521 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
522 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
523 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
524 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
525 /* Reserved for compression usage... */
526 	EXT4_INODE_DIRTY	= 8,
527 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
528 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
529 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
530 /* End compression flags --- maybe not all used */
531 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
532 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
533 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
534 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
535 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
536 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
537 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
538 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
539 	EXT4_INODE_VERITY	= 20,	/* Verity protected inode */
540 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
541 /* 22 was formerly EXT4_INODE_EOFBLOCKS */
542 	EXT4_INODE_DAX		= 25,	/* Inode is DAX */
543 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
544 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
545 	EXT4_INODE_CASEFOLD	= 30,	/* Casefolded directory */
546 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
547 };
548 
549 /*
550  * Since it's pretty easy to mix up bit numbers and hex values, we use a
551  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
552  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
553  * any extra space in the compiled kernel image, otherwise, the build will fail.
554  * It's important that these values are the same, since we are using
555  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
556  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
557  * values found in ext2, ext3 and ext4 filesystems, and of course the values
558  * defined in e2fsprogs.
559  *
560  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
561  */
562 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1U << EXT4_INODE_##FLAG))
563 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
564 
565 static inline void ext4_check_flag_values(void)
566 {
567 	CHECK_FLAG_VALUE(SECRM);
568 	CHECK_FLAG_VALUE(UNRM);
569 	CHECK_FLAG_VALUE(COMPR);
570 	CHECK_FLAG_VALUE(SYNC);
571 	CHECK_FLAG_VALUE(IMMUTABLE);
572 	CHECK_FLAG_VALUE(APPEND);
573 	CHECK_FLAG_VALUE(NODUMP);
574 	CHECK_FLAG_VALUE(NOATIME);
575 	CHECK_FLAG_VALUE(DIRTY);
576 	CHECK_FLAG_VALUE(COMPRBLK);
577 	CHECK_FLAG_VALUE(NOCOMPR);
578 	CHECK_FLAG_VALUE(ENCRYPT);
579 	CHECK_FLAG_VALUE(INDEX);
580 	CHECK_FLAG_VALUE(IMAGIC);
581 	CHECK_FLAG_VALUE(JOURNAL_DATA);
582 	CHECK_FLAG_VALUE(NOTAIL);
583 	CHECK_FLAG_VALUE(DIRSYNC);
584 	CHECK_FLAG_VALUE(TOPDIR);
585 	CHECK_FLAG_VALUE(HUGE_FILE);
586 	CHECK_FLAG_VALUE(EXTENTS);
587 	CHECK_FLAG_VALUE(VERITY);
588 	CHECK_FLAG_VALUE(EA_INODE);
589 	CHECK_FLAG_VALUE(INLINE_DATA);
590 	CHECK_FLAG_VALUE(PROJINHERIT);
591 	CHECK_FLAG_VALUE(CASEFOLD);
592 	CHECK_FLAG_VALUE(RESERVED);
593 }
594 
595 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
596 struct compat_ext4_new_group_input {
597 	u32 group;
598 	compat_u64 block_bitmap;
599 	compat_u64 inode_bitmap;
600 	compat_u64 inode_table;
601 	u32 blocks_count;
602 	u16 reserved_blocks;
603 	u16 unused;
604 };
605 #endif
606 
607 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
608 struct ext4_new_group_data {
609 	__u32 group;
610 	__u64 block_bitmap;
611 	__u64 inode_bitmap;
612 	__u64 inode_table;
613 	__u32 blocks_count;
614 	__u16 reserved_blocks;
615 	__u16 mdata_blocks;
616 	__u32 free_clusters_count;
617 };
618 
619 /* Indexes used to index group tables in ext4_new_group_data */
620 enum {
621 	BLOCK_BITMAP = 0,	/* block bitmap */
622 	INODE_BITMAP,		/* inode bitmap */
623 	INODE_TABLE,		/* inode tables */
624 	GROUP_TABLE_COUNT,
625 };
626 
627 /*
628  * Flags used by ext4_map_blocks()
629  */
630 	/* Allocate any needed blocks and/or convert an unwritten
631 	   extent to be an initialized ext4 */
632 #define EXT4_GET_BLOCKS_CREATE			0x0001
633 	/* Request the creation of an unwritten extent */
634 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
635 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
636 						 EXT4_GET_BLOCKS_CREATE)
637 	/* Caller is from the delayed allocation writeout path
638 	 * finally doing the actual allocation of delayed blocks */
639 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
640 	/* caller is from the direct IO path, request to creation of an
641 	unwritten extents if not allocated, split the unwritten
642 	extent if blocks has been preallocated already*/
643 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
644 #define EXT4_GET_BLOCKS_CONVERT			0x0010
645 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
646 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
647 	/* Convert extent to initialized after IO complete */
648 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
649 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
650 	/* Eventual metadata allocation (due to growing extent tree)
651 	 * should not fail, so try to use reserved blocks for that.*/
652 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
653 	/* Don't normalize allocation size (used for fallocate) */
654 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
655 	/* Convert written extents to unwritten */
656 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
657 	/* Write zeros to newly created written extents */
658 #define EXT4_GET_BLOCKS_ZERO			0x0200
659 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
660 					EXT4_GET_BLOCKS_ZERO)
661 	/* Caller will submit data before dropping transaction handle. This
662 	 * allows jbd2 to avoid submitting data before commit. */
663 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
664 	/* Caller is in the atomic contex, find extent if it has been cached */
665 #define EXT4_GET_BLOCKS_CACHED_NOWAIT		0x0800
666 
667 /*
668  * The bit position of these flags must not overlap with any of the
669  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
670  * read_extent_tree_block(), ext4_split_extent_at(),
671  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
672  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
673  * caching the extents when reading from the extent tree while a
674  * truncate or punch hole operation is in progress.
675  */
676 #define EXT4_EX_NOCACHE				0x40000000
677 #define EXT4_EX_FORCE_CACHE			0x20000000
678 #define EXT4_EX_NOFAIL				0x10000000
679 
680 /*
681  * Flags used by ext4_free_blocks
682  */
683 #define EXT4_FREE_BLOCKS_METADATA		0x0001
684 #define EXT4_FREE_BLOCKS_FORGET			0x0002
685 #define EXT4_FREE_BLOCKS_VALIDATED		0x0004
686 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE		0x0008
687 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
688 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
689 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
690 
691 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
692 /*
693  * ioctl commands in 32 bit emulation
694  */
695 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
696 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
697 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
698 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
699 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
700 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
701 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
702 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
703 #endif
704 
705 /* Max physical block we can address w/o extents */
706 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
707 
708 /* Max logical block we can support */
709 #define EXT4_MAX_LOGICAL_BLOCK		0xFFFFFFFE
710 
711 /*
712  * Structure of an inode on the disk
713  */
714 struct ext4_inode {
715 	__le16	i_mode;		/* File mode */
716 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
717 	__le32	i_size_lo;	/* Size in bytes */
718 	__le32	i_atime;	/* Access time */
719 	__le32	i_ctime;	/* Inode Change time */
720 	__le32	i_mtime;	/* Modification time */
721 	__le32	i_dtime;	/* Deletion Time */
722 	__le16	i_gid;		/* Low 16 bits of Group Id */
723 	__le16	i_links_count;	/* Links count */
724 	__le32	i_blocks_lo;	/* Blocks count */
725 	__le32	i_flags;	/* File flags */
726 	union {
727 		struct {
728 			__le32  l_i_version;
729 		} linux1;
730 		struct {
731 			__u32  h_i_translator;
732 		} hurd1;
733 		struct {
734 			__u32  m_i_reserved1;
735 		} masix1;
736 	} osd1;				/* OS dependent 1 */
737 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
738 	__le32	i_generation;	/* File version (for NFS) */
739 	__le32	i_file_acl_lo;	/* File ACL */
740 	__le32	i_size_high;
741 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
742 	union {
743 		struct {
744 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
745 			__le16	l_i_file_acl_high;
746 			__le16	l_i_uid_high;	/* these 2 fields */
747 			__le16	l_i_gid_high;	/* were reserved2[0] */
748 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
749 			__le16	l_i_reserved;
750 		} linux2;
751 		struct {
752 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
753 			__u16	h_i_mode_high;
754 			__u16	h_i_uid_high;
755 			__u16	h_i_gid_high;
756 			__u32	h_i_author;
757 		} hurd2;
758 		struct {
759 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
760 			__le16	m_i_file_acl_high;
761 			__u32	m_i_reserved2[2];
762 		} masix2;
763 	} osd2;				/* OS dependent 2 */
764 	__le16	i_extra_isize;
765 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
766 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
767 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
768 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
769 	__le32  i_crtime;       /* File Creation time */
770 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
771 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
772 	__le32	i_projid;	/* Project ID */
773 };
774 
775 #define EXT4_EPOCH_BITS 2
776 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
777 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
778 
779 /*
780  * Extended fields will fit into an inode if the filesystem was formatted
781  * with large inodes (-I 256 or larger) and there are not currently any EAs
782  * consuming all of the available space. For new inodes we always reserve
783  * enough space for the kernel's known extended fields, but for inodes
784  * created with an old kernel this might not have been the case. None of
785  * the extended inode fields is critical for correct filesystem operation.
786  * This macro checks if a certain field fits in the inode. Note that
787  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
788  */
789 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
790 	((offsetof(typeof(*ext4_inode), field) +	\
791 	  sizeof((ext4_inode)->field))			\
792 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
793 	    (einode)->i_extra_isize))			\
794 
795 /*
796  * We use an encoding that preserves the times for extra epoch "00":
797  *
798  * extra  msb of                         adjust for signed
799  * epoch  32-bit                         32-bit tv_sec to
800  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
801  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
802  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
803  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
804  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
805  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
806  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
807  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
808  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
809  *
810  * Note that previous versions of the kernel on 64-bit systems would
811  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
812  * 1970.  e2fsck will correct this, assuming that it is run on the
813  * affected filesystem before 2242.
814  */
815 
816 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
817 {
818 	u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
819 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
820 }
821 
822 static inline void ext4_decode_extra_time(struct timespec64 *time,
823 					  __le32 extra)
824 {
825 	if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK)))
826 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
827 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
828 }
829 
830 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)				\
831 do {										\
832 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
833 		(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	\
834 		(raw_inode)->xtime ## _extra =					\
835 				ext4_encode_extra_time(&(inode)->xtime);	\
836 		}								\
837 	else	\
838 		(raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (inode)->xtime.tv_sec, S32_MIN, S32_MAX));	\
839 } while (0)
840 
841 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
842 do {									       \
843 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
844 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
845 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
846 		(raw_inode)->xtime ## _extra =				       \
847 				ext4_encode_extra_time(&(einode)->xtime);      \
848 } while (0)
849 
850 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)				\
851 do {										\
852 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);	\
853 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {	\
854 		ext4_decode_extra_time(&(inode)->xtime,				\
855 				       raw_inode->xtime ## _extra);		\
856 		}								\
857 	else									\
858 		(inode)->xtime.tv_nsec = 0;					\
859 } while (0)
860 
861 
862 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
863 do {									       \
864 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
865 		(einode)->xtime.tv_sec = 				       \
866 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
867 	else								       \
868 		(einode)->xtime.tv_sec = 0;				       \
869 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
870 		ext4_decode_extra_time(&(einode)->xtime,		       \
871 				       raw_inode->xtime ## _extra);	       \
872 	else								       \
873 		(einode)->xtime.tv_nsec = 0;				       \
874 } while (0)
875 
876 #define i_disk_version osd1.linux1.l_i_version
877 
878 #if defined(__KERNEL__) || defined(__linux__)
879 #define i_reserved1	osd1.linux1.l_i_reserved1
880 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
881 #define i_blocks_high	osd2.linux2.l_i_blocks_high
882 #define i_uid_low	i_uid
883 #define i_gid_low	i_gid
884 #define i_uid_high	osd2.linux2.l_i_uid_high
885 #define i_gid_high	osd2.linux2.l_i_gid_high
886 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
887 
888 #elif defined(__GNU__)
889 
890 #define i_translator	osd1.hurd1.h_i_translator
891 #define i_uid_high	osd2.hurd2.h_i_uid_high
892 #define i_gid_high	osd2.hurd2.h_i_gid_high
893 #define i_author	osd2.hurd2.h_i_author
894 
895 #elif defined(__masix__)
896 
897 #define i_reserved1	osd1.masix1.m_i_reserved1
898 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
899 #define i_reserved2	osd2.masix2.m_i_reserved2
900 
901 #endif /* defined(__KERNEL__) || defined(__linux__) */
902 
903 #include "extents_status.h"
904 #include "fast_commit.h"
905 
906 /*
907  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
908  *
909  * These are needed to avoid lockdep false positives when we need to
910  * allocate blocks to the quota inode during ext4_map_blocks(), while
911  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
912  * do quota tracking for the quota inode, this avoids deadlock (as
913  * well as infinite recursion, since it isn't turtles all the way
914  * down...)
915  *
916  *  I_DATA_SEM_NORMAL - Used for most inodes
917  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
918  *			  where the second inode has larger inode number
919  *			  than the first
920  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
921  *  I_DATA_SEM_EA     - Used for ea_inodes only
922  */
923 enum {
924 	I_DATA_SEM_NORMAL = 0,
925 	I_DATA_SEM_OTHER,
926 	I_DATA_SEM_QUOTA,
927 	I_DATA_SEM_EA
928 };
929 
930 
931 /*
932  * fourth extended file system inode data in memory
933  */
934 struct ext4_inode_info {
935 	__le32	i_data[15];	/* unconverted */
936 	__u32	i_dtime;
937 	ext4_fsblk_t	i_file_acl;
938 
939 	/*
940 	 * i_block_group is the number of the block group which contains
941 	 * this file's inode.  Constant across the lifetime of the inode,
942 	 * it is used for making block allocation decisions - we try to
943 	 * place a file's data blocks near its inode block, and new inodes
944 	 * near to their parent directory's inode.
945 	 */
946 	ext4_group_t	i_block_group;
947 	ext4_lblk_t	i_dir_start_lookup;
948 #if (BITS_PER_LONG < 64)
949 	unsigned long	i_state_flags;		/* Dynamic state flags */
950 #endif
951 	unsigned long	i_flags;
952 
953 	/*
954 	 * Extended attributes can be read independently of the main file
955 	 * data. Taking i_rwsem even when reading would cause contention
956 	 * between readers of EAs and writers of regular file data, so
957 	 * instead we synchronize on xattr_sem when reading or changing
958 	 * EAs.
959 	 */
960 	struct rw_semaphore xattr_sem;
961 
962 	/*
963 	 * Inodes with EXT4_STATE_ORPHAN_FILE use i_orphan_idx. Otherwise
964 	 * i_orphan is used.
965 	 */
966 	union {
967 		struct list_head i_orphan;	/* unlinked but open inodes */
968 		unsigned int i_orphan_idx;	/* Index in orphan file */
969 	};
970 
971 	/* Fast commit related info */
972 
973 	/* For tracking dentry create updates */
974 	struct list_head i_fc_dilist;
975 	struct list_head i_fc_list;	/*
976 					 * inodes that need fast commit
977 					 * protected by sbi->s_fc_lock.
978 					 */
979 
980 	/* Start of lblk range that needs to be committed in this fast commit */
981 	ext4_lblk_t i_fc_lblk_start;
982 
983 	/* End of lblk range that needs to be committed in this fast commit */
984 	ext4_lblk_t i_fc_lblk_len;
985 
986 	/* Number of ongoing updates on this inode */
987 	atomic_t  i_fc_updates;
988 
989 	/* Fast commit wait queue for this inode */
990 	wait_queue_head_t i_fc_wait;
991 
992 	/* Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len */
993 	struct mutex i_fc_lock;
994 
995 	/*
996 	 * i_disksize keeps track of what the inode size is ON DISK, not
997 	 * in memory.  During truncate, i_size is set to the new size by
998 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
999 	 * set i_disksize to 0 until the truncate is actually under way.
1000 	 *
1001 	 * The intent is that i_disksize always represents the blocks which
1002 	 * are used by this file.  This allows recovery to restart truncate
1003 	 * on orphans if we crash during truncate.  We actually write i_disksize
1004 	 * into the on-disk inode when writing inodes out, instead of i_size.
1005 	 *
1006 	 * The only time when i_disksize and i_size may be different is when
1007 	 * a truncate is in progress.  The only things which change i_disksize
1008 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
1009 	 */
1010 	loff_t	i_disksize;
1011 
1012 	/*
1013 	 * i_data_sem is for serialising ext4_truncate() against
1014 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
1015 	 * data tree are chopped off during truncate. We can't do that in
1016 	 * ext4 because whenever we perform intermediate commits during
1017 	 * truncate, the inode and all the metadata blocks *must* be in a
1018 	 * consistent state which allows truncation of the orphans to restart
1019 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
1020 	 * by other means, so we have i_data_sem.
1021 	 */
1022 	struct rw_semaphore i_data_sem;
1023 	struct inode vfs_inode;
1024 	struct jbd2_inode *jinode;
1025 
1026 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
1027 
1028 	/*
1029 	 * File creation time. Its function is same as that of
1030 	 * struct timespec64 i_{a,c,m}time in the generic inode.
1031 	 */
1032 	struct timespec64 i_crtime;
1033 
1034 	/* mballoc */
1035 	atomic_t i_prealloc_active;
1036 	struct rb_root i_prealloc_node;
1037 	rwlock_t i_prealloc_lock;
1038 
1039 	/* extents status tree */
1040 	struct ext4_es_tree i_es_tree;
1041 	rwlock_t i_es_lock;
1042 	struct list_head i_es_list;
1043 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1044 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1045 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1046 					   extents to shrink. Protected by
1047 					   i_es_lock  */
1048 
1049 	/* ialloc */
1050 	ext4_group_t	i_last_alloc_group;
1051 
1052 	/* allocation reservation info for delalloc */
1053 	/* In case of bigalloc, this refer to clusters rather than blocks */
1054 	unsigned int i_reserved_data_blocks;
1055 
1056 	/* pending cluster reservations for bigalloc file systems */
1057 	struct ext4_pending_tree i_pending_tree;
1058 
1059 	/* on-disk additional length */
1060 	__u16 i_extra_isize;
1061 
1062 	/* Indicate the inline data space. */
1063 	u16 i_inline_off;
1064 	u16 i_inline_size;
1065 
1066 #ifdef CONFIG_QUOTA
1067 	/* quota space reservation, managed internally by quota code */
1068 	qsize_t i_reserved_quota;
1069 #endif
1070 
1071 	/* Lock protecting lists below */
1072 	spinlock_t i_completed_io_lock;
1073 	/*
1074 	 * Completed IOs that need unwritten extents handling and have
1075 	 * transaction reserved
1076 	 */
1077 	struct list_head i_rsv_conversion_list;
1078 	struct work_struct i_rsv_conversion_work;
1079 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1080 
1081 	spinlock_t i_block_reservation_lock;
1082 
1083 	/*
1084 	 * Transactions that contain inode's metadata needed to complete
1085 	 * fsync and fdatasync, respectively.
1086 	 */
1087 	tid_t i_sync_tid;
1088 	tid_t i_datasync_tid;
1089 
1090 #ifdef CONFIG_QUOTA
1091 	struct dquot *i_dquot[MAXQUOTAS];
1092 #endif
1093 
1094 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1095 	__u32 i_csum_seed;
1096 
1097 	kprojid_t i_projid;
1098 };
1099 
1100 /*
1101  * File system states
1102  */
1103 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1104 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1105 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1106 #define EXT4_FC_REPLAY			0x0020	/* Fast commit replay ongoing */
1107 
1108 /*
1109  * Misc. filesystem flags
1110  */
1111 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1112 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1113 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1114 
1115 /*
1116  * Mount flags set via mount options or defaults
1117  */
1118 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1119 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1120 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1121 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1122 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1123 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1124 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1125 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1126 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1127 #ifdef CONFIG_FS_DAX
1128 #define EXT4_MOUNT_DAX_ALWAYS		0x00200	/* Direct Access */
1129 #else
1130 #define EXT4_MOUNT_DAX_ALWAYS		0
1131 #endif
1132 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1133 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1134 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1135 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1136 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1137 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1138 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1139 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1140 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1141 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1142 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1143 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1144 						 * enable enforcement for hidden
1145 						 * quota files */
1146 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1147 						  * enforcement for hidden quota
1148 						  * files */
1149 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1150 						  * enforcement */
1151 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1152 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1153 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1154 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
1155 #define EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS 0x4000000
1156 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1157 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1158 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1159 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1160 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1161 
1162 /*
1163  * Mount flags set either automatically (could not be set by mount option)
1164  * based on per file system feature or property or in special cases such as
1165  * distinguishing between explicit mount option definition and default.
1166  */
1167 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1168 						      specified delalloc */
1169 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1170 						      size of blocksize * 8
1171 						      blocks */
1172 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1173 						      file systems */
1174 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1175 						specified journal checksum */
1176 
1177 #define EXT4_MOUNT2_JOURNAL_FAST_COMMIT	0x00000010 /* Journal fast commit */
1178 #define EXT4_MOUNT2_DAX_NEVER		0x00000020 /* Do not allow Direct Access */
1179 #define EXT4_MOUNT2_DAX_INODE		0x00000040 /* For printing options only */
1180 #define EXT4_MOUNT2_MB_OPTIMIZE_SCAN	0x00000080 /* Optimize group
1181 						    * scanning in mballoc
1182 						    */
1183 
1184 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1185 						~EXT4_MOUNT_##opt
1186 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1187 						EXT4_MOUNT_##opt
1188 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1189 					 EXT4_MOUNT_##opt)
1190 
1191 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1192 						~EXT4_MOUNT2_##opt
1193 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1194 						EXT4_MOUNT2_##opt
1195 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1196 					 EXT4_MOUNT2_##opt)
1197 
1198 #define ext4_test_and_set_bit		__test_and_set_bit_le
1199 #define ext4_set_bit			__set_bit_le
1200 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1201 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1202 #define ext4_clear_bit			__clear_bit_le
1203 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1204 #define ext4_test_bit			test_bit_le
1205 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1206 #define ext4_find_next_bit		find_next_bit_le
1207 
1208 extern void mb_set_bits(void *bm, int cur, int len);
1209 
1210 /*
1211  * Maximal mount counts between two filesystem checks
1212  */
1213 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1214 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1215 
1216 /*
1217  * Behaviour when detecting errors
1218  */
1219 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1220 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1221 #define EXT4_ERRORS_PANIC		3	/* Panic */
1222 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1223 
1224 /* Metadata checksum algorithm codes */
1225 #define EXT4_CRC32C_CHKSUM		1
1226 
1227 #define EXT4_LABEL_MAX			16
1228 
1229 /*
1230  * Structure of the super block
1231  */
1232 struct ext4_super_block {
1233 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1234 	__le32	s_blocks_count_lo;	/* Blocks count */
1235 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1236 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1237 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1238 	__le32	s_first_data_block;	/* First Data Block */
1239 	__le32	s_log_block_size;	/* Block size */
1240 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1241 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1242 	__le32	s_clusters_per_group;	/* # Clusters per group */
1243 	__le32	s_inodes_per_group;	/* # Inodes per group */
1244 	__le32	s_mtime;		/* Mount time */
1245 /*30*/	__le32	s_wtime;		/* Write time */
1246 	__le16	s_mnt_count;		/* Mount count */
1247 	__le16	s_max_mnt_count;	/* Maximal mount count */
1248 	__le16	s_magic;		/* Magic signature */
1249 	__le16	s_state;		/* File system state */
1250 	__le16	s_errors;		/* Behaviour when detecting errors */
1251 	__le16	s_minor_rev_level;	/* minor revision level */
1252 /*40*/	__le32	s_lastcheck;		/* time of last check */
1253 	__le32	s_checkinterval;	/* max. time between checks */
1254 	__le32	s_creator_os;		/* OS */
1255 	__le32	s_rev_level;		/* Revision level */
1256 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1257 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1258 	/*
1259 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1260 	 *
1261 	 * Note: the difference between the compatible feature set and
1262 	 * the incompatible feature set is that if there is a bit set
1263 	 * in the incompatible feature set that the kernel doesn't
1264 	 * know about, it should refuse to mount the filesystem.
1265 	 *
1266 	 * e2fsck's requirements are more strict; if it doesn't know
1267 	 * about a feature in either the compatible or incompatible
1268 	 * feature set, it must abort and not try to meddle with
1269 	 * things it doesn't understand...
1270 	 */
1271 	__le32	s_first_ino;		/* First non-reserved inode */
1272 	__le16  s_inode_size;		/* size of inode structure */
1273 	__le16	s_block_group_nr;	/* block group # of this superblock */
1274 	__le32	s_feature_compat;	/* compatible feature set */
1275 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1276 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1277 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1278 /*78*/	char	s_volume_name[EXT4_LABEL_MAX];	/* volume name */
1279 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
1280 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1281 	/*
1282 	 * Performance hints.  Directory preallocation should only
1283 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1284 	 */
1285 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1286 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1287 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1288 	/*
1289 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1290 	 */
1291 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1292 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1293 	__le32	s_journal_dev;		/* device number of journal file */
1294 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1295 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1296 	__u8	s_def_hash_version;	/* Default hash version to use */
1297 	__u8	s_jnl_backup_type;
1298 	__le16  s_desc_size;		/* size of group descriptor */
1299 /*100*/	__le32	s_default_mount_opts;
1300 	__le32	s_first_meta_bg;	/* First metablock block group */
1301 	__le32	s_mkfs_time;		/* When the filesystem was created */
1302 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1303 	/* 64bit support valid if EXT4_FEATURE_INCOMPAT_64BIT */
1304 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1305 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1306 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1307 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1308 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1309 	__le32	s_flags;		/* Miscellaneous flags */
1310 	__le16  s_raid_stride;		/* RAID stride */
1311 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1312 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1313 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1314 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1315 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1316 	__u8	s_encryption_level;	/* versioning level for encryption */
1317 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1318 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1319 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1320 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1321 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1322 					      snapshot's future use */
1323 	__le32	s_snapshot_list;	/* inode number of the head of the
1324 					   on-disk snapshot list */
1325 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1326 	__le32	s_error_count;		/* number of fs errors */
1327 	__le32	s_first_error_time;	/* first time an error happened */
1328 	__le32	s_first_error_ino;	/* inode involved in first error */
1329 	__le64	s_first_error_block;	/* block involved of first error */
1330 	__u8	s_first_error_func[32] __nonstring;	/* function where the error happened */
1331 	__le32	s_first_error_line;	/* line number where error happened */
1332 	__le32	s_last_error_time;	/* most recent time of an error */
1333 	__le32	s_last_error_ino;	/* inode involved in last error */
1334 	__le32	s_last_error_line;	/* line number where error happened */
1335 	__le64	s_last_error_block;	/* block involved of last error */
1336 	__u8	s_last_error_func[32] __nonstring;	/* function where the error happened */
1337 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1338 	__u8	s_mount_opts[64];
1339 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1340 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1341 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1342 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1343 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1344 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1345 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1346 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1347 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1348 	__u8	s_wtime_hi;
1349 	__u8	s_mtime_hi;
1350 	__u8	s_mkfs_time_hi;
1351 	__u8	s_lastcheck_hi;
1352 	__u8	s_first_error_time_hi;
1353 	__u8	s_last_error_time_hi;
1354 	__u8	s_first_error_errcode;
1355 	__u8    s_last_error_errcode;
1356 	__le16  s_encoding;		/* Filename charset encoding */
1357 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
1358 	__le32  s_orphan_file_inum;	/* Inode for tracking orphan inodes */
1359 	__le32	s_reserved[94];		/* Padding to the end of the block */
1360 	__le32	s_checksum;		/* crc32c(superblock) */
1361 };
1362 
1363 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1364 
1365 #ifdef __KERNEL__
1366 
1367 /* Number of quota types we support */
1368 #define EXT4_MAXQUOTAS 3
1369 
1370 #define EXT4_ENC_UTF8_12_1	1
1371 
1372 /* Types of ext4 journal triggers */
1373 enum ext4_journal_trigger_type {
1374 	EXT4_JTR_ORPHAN_FILE,
1375 	EXT4_JTR_NONE	/* This must be the last entry for indexing to work! */
1376 };
1377 
1378 #define EXT4_JOURNAL_TRIGGER_COUNT EXT4_JTR_NONE
1379 
1380 struct ext4_journal_trigger {
1381 	struct jbd2_buffer_trigger_type tr_triggers;
1382 	struct super_block *sb;
1383 };
1384 
1385 static inline struct ext4_journal_trigger *EXT4_TRIGGER(
1386 				struct jbd2_buffer_trigger_type *trigger)
1387 {
1388 	return container_of(trigger, struct ext4_journal_trigger, tr_triggers);
1389 }
1390 
1391 #define EXT4_ORPHAN_BLOCK_MAGIC 0x0b10ca04
1392 
1393 /* Structure at the tail of orphan block */
1394 struct ext4_orphan_block_tail {
1395 	__le32 ob_magic;
1396 	__le32 ob_checksum;
1397 };
1398 
1399 static inline int ext4_inodes_per_orphan_block(struct super_block *sb)
1400 {
1401 	return (sb->s_blocksize - sizeof(struct ext4_orphan_block_tail)) /
1402 			sizeof(u32);
1403 }
1404 
1405 struct ext4_orphan_block {
1406 	atomic_t ob_free_entries;	/* Number of free orphan entries in block */
1407 	struct buffer_head *ob_bh;	/* Buffer for orphan block */
1408 };
1409 
1410 /*
1411  * Info about orphan file.
1412  */
1413 struct ext4_orphan_info {
1414 	int of_blocks;			/* Number of orphan blocks in a file */
1415 	__u32 of_csum_seed;		/* Checksum seed for orphan file */
1416 	struct ext4_orphan_block *of_binfo;	/* Array with info about orphan
1417 						 * file blocks */
1418 };
1419 
1420 /*
1421  * fourth extended-fs super-block data in memory
1422  */
1423 struct ext4_sb_info {
1424 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1425 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1426 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1427 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1428 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1429 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1430 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1431 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1432 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1433 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1434 	unsigned long s_overhead;  /* # of fs overhead clusters */
1435 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1436 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1437 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1438 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1439 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1440 	struct buffer_head * __rcu *s_group_desc;
1441 	unsigned int s_mount_opt;
1442 	unsigned int s_mount_opt2;
1443 	unsigned long s_mount_flags;
1444 	unsigned int s_def_mount_opt;
1445 	unsigned int s_def_mount_opt2;
1446 	ext4_fsblk_t s_sb_block;
1447 	atomic64_t s_resv_clusters;
1448 	kuid_t s_resuid;
1449 	kgid_t s_resgid;
1450 	unsigned short s_mount_state;
1451 	unsigned short s_pad;
1452 	int s_addr_per_block_bits;
1453 	int s_desc_per_block_bits;
1454 	int s_inode_size;
1455 	int s_first_ino;
1456 	unsigned int s_inode_readahead_blks;
1457 	unsigned int s_inode_goal;
1458 	u32 s_hash_seed[4];
1459 	int s_def_hash_version;
1460 	int s_hash_unsigned;	/* 3 if hash should be unsigned, 0 if not */
1461 	struct percpu_counter s_freeclusters_counter;
1462 	struct percpu_counter s_freeinodes_counter;
1463 	struct percpu_counter s_dirs_counter;
1464 	struct percpu_counter s_dirtyclusters_counter;
1465 	struct percpu_counter s_sra_exceeded_retry_limit;
1466 	struct blockgroup_lock *s_blockgroup_lock;
1467 	struct proc_dir_entry *s_proc;
1468 	struct kobject s_kobj;
1469 	struct completion s_kobj_unregister;
1470 	struct super_block *s_sb;
1471 	struct buffer_head *s_mmp_bh;
1472 
1473 	/* Journaling */
1474 	struct journal_s *s_journal;
1475 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1476 	struct mutex s_orphan_lock;	/* Protects on disk list changes */
1477 	struct list_head s_orphan;	/* List of orphaned inodes in on disk
1478 					   list */
1479 	struct ext4_orphan_info s_orphan_info;
1480 	unsigned long s_commit_interval;
1481 	u32 s_max_batch_time;
1482 	u32 s_min_batch_time;
1483 	struct block_device *s_journal_bdev;
1484 #ifdef CONFIG_QUOTA
1485 	/* Names of quota files with journalled quota */
1486 	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1487 	int s_jquota_fmt;			/* Format of quota to use */
1488 #endif
1489 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1490 	struct ext4_system_blocks __rcu *s_system_blks;
1491 
1492 #ifdef EXTENTS_STATS
1493 	/* ext4 extents stats */
1494 	unsigned long s_ext_min;
1495 	unsigned long s_ext_max;
1496 	unsigned long s_depth_max;
1497 	spinlock_t s_ext_stats_lock;
1498 	unsigned long s_ext_blocks;
1499 	unsigned long s_ext_extents;
1500 #endif
1501 
1502 	/* for buddy allocator */
1503 	struct ext4_group_info ** __rcu *s_group_info;
1504 	struct inode *s_buddy_cache;
1505 	spinlock_t s_md_lock;
1506 	unsigned short *s_mb_offsets;
1507 	unsigned int *s_mb_maxs;
1508 	unsigned int s_group_info_size;
1509 	unsigned int s_mb_free_pending;
1510 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1511 						   after commit completed */
1512 	struct list_head s_discard_list;
1513 	struct work_struct s_discard_work;
1514 	atomic_t s_retry_alloc_pending;
1515 	struct list_head *s_mb_avg_fragment_size;
1516 	rwlock_t *s_mb_avg_fragment_size_locks;
1517 	struct list_head *s_mb_largest_free_orders;
1518 	rwlock_t *s_mb_largest_free_orders_locks;
1519 
1520 	/* tunables */
1521 	unsigned long s_stripe;
1522 	unsigned int s_mb_max_linear_groups;
1523 	unsigned int s_mb_stream_request;
1524 	unsigned int s_mb_max_to_scan;
1525 	unsigned int s_mb_min_to_scan;
1526 	unsigned int s_mb_stats;
1527 	unsigned int s_mb_order2_reqs;
1528 	unsigned int s_mb_group_prealloc;
1529 	unsigned int s_max_dir_size_kb;
1530 	/* where last allocation was done - for stream allocation */
1531 	unsigned long s_mb_last_group;
1532 	unsigned long s_mb_last_start;
1533 	unsigned int s_mb_prefetch;
1534 	unsigned int s_mb_prefetch_limit;
1535 
1536 	/* stats for buddy allocator */
1537 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1538 	atomic_t s_bal_success;	/* we found long enough chunks */
1539 	atomic_t s_bal_allocated;	/* in blocks */
1540 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1541 	atomic_t s_bal_groups_scanned;	/* number of groups scanned */
1542 	atomic_t s_bal_goals;	/* goal hits */
1543 	atomic_t s_bal_breaks;	/* too long searches */
1544 	atomic_t s_bal_2orders;	/* 2^order hits */
1545 	atomic_t s_bal_cr0_bad_suggestions;
1546 	atomic_t s_bal_cr1_bad_suggestions;
1547 	atomic64_t s_bal_cX_groups_considered[4];
1548 	atomic64_t s_bal_cX_hits[4];
1549 	atomic64_t s_bal_cX_failed[4];		/* cX loop didn't find blocks */
1550 	atomic_t s_mb_buddies_generated;	/* number of buddies generated */
1551 	atomic64_t s_mb_generation_time;
1552 	atomic_t s_mb_lost_chunks;
1553 	atomic_t s_mb_preallocated;
1554 	atomic_t s_mb_discarded;
1555 	atomic_t s_lock_busy;
1556 
1557 	/* locality groups */
1558 	struct ext4_locality_group __percpu *s_locality_groups;
1559 
1560 	/* for write statistics */
1561 	unsigned long s_sectors_written_start;
1562 	u64 s_kbytes_written;
1563 
1564 	/* the size of zero-out chunk */
1565 	unsigned int s_extent_max_zeroout_kb;
1566 
1567 	unsigned int s_log_groups_per_flex;
1568 	struct flex_groups * __rcu *s_flex_groups;
1569 	ext4_group_t s_flex_groups_allocated;
1570 
1571 	/* workqueue for reserved extent conversions (buffered io) */
1572 	struct workqueue_struct *rsv_conversion_wq;
1573 
1574 	/* timer for periodic error stats printing */
1575 	struct timer_list s_err_report;
1576 
1577 	/* Lazy inode table initialization info */
1578 	struct ext4_li_request *s_li_request;
1579 	/* Wait multiplier for lazy initialization thread */
1580 	unsigned int s_li_wait_mult;
1581 
1582 	/* Kernel thread for multiple mount protection */
1583 	struct task_struct *s_mmp_tsk;
1584 
1585 	/* record the last minlen when FITRIM is called. */
1586 	unsigned long s_last_trim_minblks;
1587 
1588 	/* Reference to checksum algorithm driver via cryptoapi */
1589 	struct crypto_shash *s_chksum_driver;
1590 
1591 	/* Precomputed FS UUID checksum for seeding other checksums */
1592 	__u32 s_csum_seed;
1593 
1594 	/* Reclaim extents from extent status tree */
1595 	struct shrinker s_es_shrinker;
1596 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1597 	long s_es_nr_inode;
1598 	struct ext4_es_stats s_es_stats;
1599 	struct mb_cache *s_ea_block_cache;
1600 	struct mb_cache *s_ea_inode_cache;
1601 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1602 
1603 	/* Journal triggers for checksum computation */
1604 	struct ext4_journal_trigger s_journal_triggers[EXT4_JOURNAL_TRIGGER_COUNT];
1605 
1606 	/* Ratelimit ext4 messages. */
1607 	struct ratelimit_state s_err_ratelimit_state;
1608 	struct ratelimit_state s_warning_ratelimit_state;
1609 	struct ratelimit_state s_msg_ratelimit_state;
1610 	atomic_t s_warning_count;
1611 	atomic_t s_msg_count;
1612 
1613 	/* Encryption policy for '-o test_dummy_encryption' */
1614 	struct fscrypt_dummy_policy s_dummy_enc_policy;
1615 
1616 	/*
1617 	 * Barrier between writepages ops and changing any inode's JOURNAL_DATA
1618 	 * or EXTENTS flag.
1619 	 */
1620 	struct percpu_rw_semaphore s_writepages_rwsem;
1621 	struct dax_device *s_daxdev;
1622 	u64 s_dax_part_off;
1623 #ifdef CONFIG_EXT4_DEBUG
1624 	unsigned long s_simulate_fail;
1625 #endif
1626 	/* Record the errseq of the backing block device */
1627 	errseq_t s_bdev_wb_err;
1628 	spinlock_t s_bdev_wb_lock;
1629 
1630 	/* Information about errors that happened during this mount */
1631 	spinlock_t s_error_lock;
1632 	int s_add_error_count;
1633 	int s_first_error_code;
1634 	__u32 s_first_error_line;
1635 	__u32 s_first_error_ino;
1636 	__u64 s_first_error_block;
1637 	const char *s_first_error_func;
1638 	time64_t s_first_error_time;
1639 	int s_last_error_code;
1640 	__u32 s_last_error_line;
1641 	__u32 s_last_error_ino;
1642 	__u64 s_last_error_block;
1643 	const char *s_last_error_func;
1644 	time64_t s_last_error_time;
1645 	/*
1646 	 * If we are in a context where we cannot update error information in
1647 	 * the on-disk superblock, we queue this work to do it.
1648 	 */
1649 	struct work_struct s_error_work;
1650 
1651 	/* Ext4 fast commit sub transaction ID */
1652 	atomic_t s_fc_subtid;
1653 
1654 	/*
1655 	 * After commit starts, the main queue gets locked, and the further
1656 	 * updates get added in the staging queue.
1657 	 */
1658 #define FC_Q_MAIN	0
1659 #define FC_Q_STAGING	1
1660 	struct list_head s_fc_q[2];	/* Inodes staged for fast commit
1661 					 * that have data changes in them.
1662 					 */
1663 	struct list_head s_fc_dentry_q[2];	/* directory entry updates */
1664 	unsigned int s_fc_bytes;
1665 	/*
1666 	 * Main fast commit lock. This lock protects accesses to the
1667 	 * following fields:
1668 	 * ei->i_fc_list, s_fc_dentry_q, s_fc_q, s_fc_bytes, s_fc_bh.
1669 	 */
1670 	spinlock_t s_fc_lock;
1671 	struct buffer_head *s_fc_bh;
1672 	struct ext4_fc_stats s_fc_stats;
1673 	tid_t s_fc_ineligible_tid;
1674 #ifdef CONFIG_EXT4_DEBUG
1675 	int s_fc_debug_max_replay;
1676 #endif
1677 	struct ext4_fc_replay_state s_fc_replay_state;
1678 };
1679 
1680 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1681 {
1682 	return sb->s_fs_info;
1683 }
1684 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1685 {
1686 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1687 }
1688 
1689 static inline int ext4_writepages_down_read(struct super_block *sb)
1690 {
1691 	percpu_down_read(&EXT4_SB(sb)->s_writepages_rwsem);
1692 	return memalloc_nofs_save();
1693 }
1694 
1695 static inline void ext4_writepages_up_read(struct super_block *sb, int ctx)
1696 {
1697 	memalloc_nofs_restore(ctx);
1698 	percpu_up_read(&EXT4_SB(sb)->s_writepages_rwsem);
1699 }
1700 
1701 static inline int ext4_writepages_down_write(struct super_block *sb)
1702 {
1703 	percpu_down_write(&EXT4_SB(sb)->s_writepages_rwsem);
1704 	return memalloc_nofs_save();
1705 }
1706 
1707 static inline void ext4_writepages_up_write(struct super_block *sb, int ctx)
1708 {
1709 	memalloc_nofs_restore(ctx);
1710 	percpu_up_write(&EXT4_SB(sb)->s_writepages_rwsem);
1711 }
1712 
1713 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1714 {
1715 	return ino == EXT4_ROOT_INO ||
1716 		(ino >= EXT4_FIRST_INO(sb) &&
1717 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1718 }
1719 
1720 /*
1721  * Returns: sbi->field[index]
1722  * Used to access an array element from the following sbi fields which require
1723  * rcu protection to avoid dereferencing an invalid pointer due to reassignment
1724  * - s_group_desc
1725  * - s_group_info
1726  * - s_flex_group
1727  */
1728 #define sbi_array_rcu_deref(sbi, field, index)				   \
1729 ({									   \
1730 	typeof(*((sbi)->field)) _v;					   \
1731 	rcu_read_lock();						   \
1732 	_v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index];	   \
1733 	rcu_read_unlock();						   \
1734 	_v;								   \
1735 })
1736 
1737 /*
1738  * run-time mount flags
1739  */
1740 enum {
1741 	EXT4_MF_MNTDIR_SAMPLED,
1742 	EXT4_MF_FS_ABORTED,	/* Fatal error detected */
1743 	EXT4_MF_FC_INELIGIBLE	/* Fast commit ineligible */
1744 };
1745 
1746 static inline void ext4_set_mount_flag(struct super_block *sb, int bit)
1747 {
1748 	set_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1749 }
1750 
1751 static inline void ext4_clear_mount_flag(struct super_block *sb, int bit)
1752 {
1753 	clear_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1754 }
1755 
1756 static inline int ext4_test_mount_flag(struct super_block *sb, int bit)
1757 {
1758 	return test_bit(bit, &EXT4_SB(sb)->s_mount_flags);
1759 }
1760 
1761 
1762 /*
1763  * Simulate_fail codes
1764  */
1765 #define EXT4_SIM_BBITMAP_EIO	1
1766 #define EXT4_SIM_BBITMAP_CRC	2
1767 #define EXT4_SIM_IBITMAP_EIO	3
1768 #define EXT4_SIM_IBITMAP_CRC	4
1769 #define EXT4_SIM_INODE_EIO	5
1770 #define EXT4_SIM_INODE_CRC	6
1771 #define EXT4_SIM_DIRBLOCK_EIO	7
1772 #define EXT4_SIM_DIRBLOCK_CRC	8
1773 
1774 static inline bool ext4_simulate_fail(struct super_block *sb,
1775 				     unsigned long code)
1776 {
1777 #ifdef CONFIG_EXT4_DEBUG
1778 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1779 
1780 	if (unlikely(sbi->s_simulate_fail == code)) {
1781 		sbi->s_simulate_fail = 0;
1782 		return true;
1783 	}
1784 #endif
1785 	return false;
1786 }
1787 
1788 static inline void ext4_simulate_fail_bh(struct super_block *sb,
1789 					 struct buffer_head *bh,
1790 					 unsigned long code)
1791 {
1792 	if (!IS_ERR(bh) && ext4_simulate_fail(sb, code))
1793 		clear_buffer_uptodate(bh);
1794 }
1795 
1796 /*
1797  * Error number codes for s_{first,last}_error_errno
1798  *
1799  * Linux errno numbers are architecture specific, so we need to translate
1800  * them into something which is architecture independent.   We don't define
1801  * codes for all errno's; just the ones which are most likely to be the cause
1802  * of an ext4_error() call.
1803  */
1804 #define EXT4_ERR_UNKNOWN	 1
1805 #define EXT4_ERR_EIO		 2
1806 #define EXT4_ERR_ENOMEM		 3
1807 #define EXT4_ERR_EFSBADCRC	 4
1808 #define EXT4_ERR_EFSCORRUPTED	 5
1809 #define EXT4_ERR_ENOSPC		 6
1810 #define EXT4_ERR_ENOKEY		 7
1811 #define EXT4_ERR_EROFS		 8
1812 #define EXT4_ERR_EFBIG		 9
1813 #define EXT4_ERR_EEXIST		10
1814 #define EXT4_ERR_ERANGE		11
1815 #define EXT4_ERR_EOVERFLOW	12
1816 #define EXT4_ERR_EBUSY		13
1817 #define EXT4_ERR_ENOTDIR	14
1818 #define EXT4_ERR_ENOTEMPTY	15
1819 #define EXT4_ERR_ESHUTDOWN	16
1820 #define EXT4_ERR_EFAULT		17
1821 
1822 /*
1823  * Inode dynamic state flags
1824  */
1825 enum {
1826 	EXT4_STATE_NEW,			/* inode is newly created */
1827 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1828 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1829 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1830 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1831 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1832 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1833 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1834 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1835 	EXT4_STATE_VERITY_IN_PROGRESS,	/* building fs-verity Merkle tree */
1836 	EXT4_STATE_FC_COMMITTING,	/* Fast commit ongoing */
1837 	EXT4_STATE_ORPHAN_FILE,		/* Inode orphaned in orphan file */
1838 };
1839 
1840 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1841 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1842 {									\
1843 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1844 }									\
1845 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1846 {									\
1847 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1848 }									\
1849 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1850 {									\
1851 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1852 }
1853 
1854 /* Add these declarations here only so that these functions can be
1855  * found by name.  Otherwise, they are very hard to locate. */
1856 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1857 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1858 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1859 EXT4_INODE_BIT_FNS(flag, flags, 0)
1860 
1861 /* Add these declarations here only so that these functions can be
1862  * found by name.  Otherwise, they are very hard to locate. */
1863 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1864 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1865 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1866 #if (BITS_PER_LONG < 64)
1867 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1868 
1869 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1870 {
1871 	(ei)->i_state_flags = 0;
1872 }
1873 #else
1874 EXT4_INODE_BIT_FNS(state, flags, 32)
1875 
1876 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1877 {
1878 	/* We depend on the fact that callers will set i_flags */
1879 }
1880 #endif
1881 #else
1882 /* Assume that user mode programs are passing in an ext4fs superblock, not
1883  * a kernel struct super_block.  This will allow us to call the feature-test
1884  * macros from user land. */
1885 #define EXT4_SB(sb)	(sb)
1886 #endif
1887 
1888 static inline bool ext4_verity_in_progress(struct inode *inode)
1889 {
1890 	return IS_ENABLED(CONFIG_FS_VERITY) &&
1891 	       ext4_test_inode_state(inode, EXT4_STATE_VERITY_IN_PROGRESS);
1892 }
1893 
1894 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1895 
1896 /*
1897  * Codes for operating systems
1898  */
1899 #define EXT4_OS_LINUX		0
1900 #define EXT4_OS_HURD		1
1901 #define EXT4_OS_MASIX		2
1902 #define EXT4_OS_FREEBSD		3
1903 #define EXT4_OS_LITES		4
1904 
1905 /*
1906  * Revision levels
1907  */
1908 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1909 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1910 
1911 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1912 
1913 #define EXT4_GOOD_OLD_INODE_SIZE 128
1914 
1915 #define EXT4_EXTRA_TIMESTAMP_MAX	(((s64)1 << 34) - 1  + S32_MIN)
1916 #define EXT4_NON_EXTRA_TIMESTAMP_MAX	S32_MAX
1917 #define EXT4_TIMESTAMP_MIN		S32_MIN
1918 
1919 /*
1920  * Feature set definitions
1921  */
1922 
1923 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1924 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1925 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1926 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1927 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1928 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1929 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1930 /*
1931  * The reason why "FAST_COMMIT" is a compat feature is that, FS becomes
1932  * incompatible only if fast commit blocks are present in the FS. Since we
1933  * clear the journal (and thus the fast commit blocks), we don't mark FS as
1934  * incompatible. We also have a JBD2 incompat feature, which gets set when
1935  * there are fast commit blocks present in the journal.
1936  */
1937 #define EXT4_FEATURE_COMPAT_FAST_COMMIT		0x0400
1938 #define EXT4_FEATURE_COMPAT_STABLE_INODES	0x0800
1939 #define EXT4_FEATURE_COMPAT_ORPHAN_FILE		0x1000	/* Orphan file exists */
1940 
1941 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1942 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1943 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1944 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1945 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1946 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1947 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1948 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1949 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1950 /*
1951  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1952  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1953  * all other data structures' checksums.  However, the METADATA_CSUM and
1954  * GDT_CSUM bits are mutually exclusive.
1955  */
1956 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1957 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1958 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1959 #define EXT4_FEATURE_RO_COMPAT_VERITY		0x8000
1960 #define EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT	0x10000 /* Orphan file may be
1961 							   non-empty */
1962 
1963 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1964 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1965 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1966 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1967 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1968 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1969 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1970 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1971 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1972 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1973 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1974 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1975 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1976 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1977 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1978 #define EXT4_FEATURE_INCOMPAT_CASEFOLD		0x20000
1979 
1980 extern void ext4_update_dynamic_rev(struct super_block *sb);
1981 
1982 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1983 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1984 { \
1985 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1986 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1987 } \
1988 static inline void ext4_set_feature_##name(struct super_block *sb) \
1989 { \
1990 	ext4_update_dynamic_rev(sb); \
1991 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1992 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1993 } \
1994 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1995 { \
1996 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1997 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1998 }
1999 
2000 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
2001 static inline bool ext4_has_feature_##name(struct super_block *sb) \
2002 { \
2003 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2004 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
2005 } \
2006 static inline void ext4_set_feature_##name(struct super_block *sb) \
2007 { \
2008 	ext4_update_dynamic_rev(sb); \
2009 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
2010 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
2011 } \
2012 static inline void ext4_clear_feature_##name(struct super_block *sb) \
2013 { \
2014 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
2015 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
2016 }
2017 
2018 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
2019 static inline bool ext4_has_feature_##name(struct super_block *sb) \
2020 { \
2021 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2022 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
2023 } \
2024 static inline void ext4_set_feature_##name(struct super_block *sb) \
2025 { \
2026 	ext4_update_dynamic_rev(sb); \
2027 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
2028 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2029 } \
2030 static inline void ext4_clear_feature_##name(struct super_block *sb) \
2031 { \
2032 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
2033 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
2034 }
2035 
2036 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
2037 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
2038 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
2039 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
2040 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
2041 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
2042 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
2043 EXT4_FEATURE_COMPAT_FUNCS(fast_commit,		FAST_COMMIT)
2044 EXT4_FEATURE_COMPAT_FUNCS(stable_inodes,	STABLE_INODES)
2045 EXT4_FEATURE_COMPAT_FUNCS(orphan_file,		ORPHAN_FILE)
2046 
2047 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
2048 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
2049 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
2050 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
2051 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
2052 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
2053 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
2054 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
2055 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
2056 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
2057 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
2058 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
2059 EXT4_FEATURE_RO_COMPAT_FUNCS(verity,		VERITY)
2060 EXT4_FEATURE_RO_COMPAT_FUNCS(orphan_present,	ORPHAN_PRESENT)
2061 
2062 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
2063 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
2064 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
2065 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
2066 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
2067 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
2068 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
2069 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
2070 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
2071 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
2072 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
2073 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
2074 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
2075 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
2076 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
2077 EXT4_FEATURE_INCOMPAT_FUNCS(casefold,		CASEFOLD)
2078 
2079 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2080 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2081 					 EXT4_FEATURE_INCOMPAT_META_BG)
2082 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2083 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2084 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2085 
2086 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2087 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2088 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
2089 					 EXT4_FEATURE_INCOMPAT_META_BG)
2090 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2091 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2092 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2093 
2094 #define EXT4_FEATURE_COMPAT_SUPP	(EXT4_FEATURE_COMPAT_EXT_ATTR| \
2095 					 EXT4_FEATURE_COMPAT_ORPHAN_FILE)
2096 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2097 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
2098 					 EXT4_FEATURE_INCOMPAT_META_BG| \
2099 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
2100 					 EXT4_FEATURE_INCOMPAT_64BIT| \
2101 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
2102 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
2103 					 EXT4_FEATURE_INCOMPAT_MMP | \
2104 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
2105 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
2106 					 EXT4_FEATURE_INCOMPAT_CASEFOLD | \
2107 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
2108 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
2109 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2110 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2111 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
2112 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
2113 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
2114 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
2115 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
2116 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
2117 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
2118 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
2119 					 EXT4_FEATURE_RO_COMPAT_PROJECT |\
2120 					 EXT4_FEATURE_RO_COMPAT_VERITY |\
2121 					 EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT)
2122 
2123 #define EXTN_FEATURE_FUNCS(ver) \
2124 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
2125 { \
2126 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
2127 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
2128 } \
2129 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
2130 { \
2131 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2132 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
2133 } \
2134 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
2135 { \
2136 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2137 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
2138 }
2139 
2140 EXTN_FEATURE_FUNCS(2)
2141 EXTN_FEATURE_FUNCS(3)
2142 EXTN_FEATURE_FUNCS(4)
2143 
2144 static inline bool ext4_has_compat_features(struct super_block *sb)
2145 {
2146 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
2147 }
2148 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
2149 {
2150 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
2151 }
2152 static inline bool ext4_has_incompat_features(struct super_block *sb)
2153 {
2154 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
2155 }
2156 
2157 extern int ext4_feature_set_ok(struct super_block *sb, int readonly);
2158 
2159 /*
2160  * Superblock flags
2161  */
2162 #define EXT4_FLAGS_RESIZING	0
2163 #define EXT4_FLAGS_SHUTDOWN	1
2164 #define EXT4_FLAGS_BDEV_IS_DAX	2
2165 
2166 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
2167 {
2168 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
2169 }
2170 
2171 /*
2172  * Default values for user and/or group using reserved blocks
2173  */
2174 #define	EXT4_DEF_RESUID		0
2175 #define	EXT4_DEF_RESGID		0
2176 
2177 /*
2178  * Default project ID
2179  */
2180 #define	EXT4_DEF_PROJID		0
2181 
2182 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
2183 
2184 /*
2185  * Default mount options
2186  */
2187 #define EXT4_DEFM_DEBUG		0x0001
2188 #define EXT4_DEFM_BSDGROUPS	0x0002
2189 #define EXT4_DEFM_XATTR_USER	0x0004
2190 #define EXT4_DEFM_ACL		0x0008
2191 #define EXT4_DEFM_UID16		0x0010
2192 #define EXT4_DEFM_JMODE		0x0060
2193 #define EXT4_DEFM_JMODE_DATA	0x0020
2194 #define EXT4_DEFM_JMODE_ORDERED	0x0040
2195 #define EXT4_DEFM_JMODE_WBACK	0x0060
2196 #define EXT4_DEFM_NOBARRIER	0x0100
2197 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
2198 #define EXT4_DEFM_DISCARD	0x0400
2199 #define EXT4_DEFM_NODELALLOC	0x0800
2200 
2201 /*
2202  * Default journal batch times
2203  */
2204 #define EXT4_DEF_MIN_BATCH_TIME	0
2205 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
2206 
2207 /*
2208  * Minimum number of groups in a flexgroup before we separate out
2209  * directories into the first block group of a flexgroup
2210  */
2211 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
2212 
2213 /*
2214  * Structure of a directory entry
2215  */
2216 #define EXT4_NAME_LEN 255
2217 /*
2218  * Base length of the ext4 directory entry excluding the name length
2219  */
2220 #define EXT4_BASE_DIR_LEN (sizeof(struct ext4_dir_entry_2) - EXT4_NAME_LEN)
2221 
2222 struct ext4_dir_entry {
2223 	__le32	inode;			/* Inode number */
2224 	__le16	rec_len;		/* Directory entry length */
2225 	__le16	name_len;		/* Name length */
2226 	char	name[EXT4_NAME_LEN];	/* File name */
2227 };
2228 
2229 
2230 /*
2231  * Encrypted Casefolded entries require saving the hash on disk. This structure
2232  * followed ext4_dir_entry_2's name[name_len] at the next 4 byte aligned
2233  * boundary.
2234  */
2235 struct ext4_dir_entry_hash {
2236 	__le32 hash;
2237 	__le32 minor_hash;
2238 };
2239 
2240 /*
2241  * The new version of the directory entry.  Since EXT4 structures are
2242  * stored in intel byte order, and the name_len field could never be
2243  * bigger than 255 chars, it's safe to reclaim the extra byte for the
2244  * file_type field.
2245  */
2246 struct ext4_dir_entry_2 {
2247 	__le32	inode;			/* Inode number */
2248 	__le16	rec_len;		/* Directory entry length */
2249 	__u8	name_len;		/* Name length */
2250 	__u8	file_type;		/* See file type macros EXT4_FT_* below */
2251 	char	name[EXT4_NAME_LEN];	/* File name */
2252 };
2253 
2254 /*
2255  * Access the hashes at the end of ext4_dir_entry_2
2256  */
2257 #define EXT4_DIRENT_HASHES(entry) \
2258 	((struct ext4_dir_entry_hash *) \
2259 		(((void *)(entry)) + \
2260 		((8 + (entry)->name_len + EXT4_DIR_ROUND) & ~EXT4_DIR_ROUND)))
2261 #define EXT4_DIRENT_HASH(entry) le32_to_cpu(EXT4_DIRENT_HASHES(de)->hash)
2262 #define EXT4_DIRENT_MINOR_HASH(entry) \
2263 		le32_to_cpu(EXT4_DIRENT_HASHES(de)->minor_hash)
2264 
2265 static inline bool ext4_hash_in_dirent(const struct inode *inode)
2266 {
2267 	return IS_CASEFOLDED(inode) && IS_ENCRYPTED(inode);
2268 }
2269 
2270 /*
2271  * This is a bogus directory entry at the end of each leaf block that
2272  * records checksums.
2273  */
2274 struct ext4_dir_entry_tail {
2275 	__le32	det_reserved_zero1;	/* Pretend to be unused */
2276 	__le16	det_rec_len;		/* 12 */
2277 	__u8	det_reserved_zero2;	/* Zero name length */
2278 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
2279 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
2280 };
2281 
2282 #define EXT4_DIRENT_TAIL(block, blocksize) \
2283 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
2284 					((blocksize) - \
2285 					 sizeof(struct ext4_dir_entry_tail))))
2286 
2287 /*
2288  * Ext4 directory file types.  Only the low 3 bits are used.  The
2289  * other bits are reserved for now.
2290  */
2291 #define EXT4_FT_UNKNOWN		0
2292 #define EXT4_FT_REG_FILE	1
2293 #define EXT4_FT_DIR		2
2294 #define EXT4_FT_CHRDEV		3
2295 #define EXT4_FT_BLKDEV		4
2296 #define EXT4_FT_FIFO		5
2297 #define EXT4_FT_SOCK		6
2298 #define EXT4_FT_SYMLINK		7
2299 
2300 #define EXT4_FT_MAX		8
2301 
2302 #define EXT4_FT_DIR_CSUM	0xDE
2303 
2304 /*
2305  * EXT4_DIR_PAD defines the directory entries boundaries
2306  *
2307  * NOTE: It must be a multiple of 4
2308  */
2309 #define EXT4_DIR_PAD			4
2310 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
2311 #define EXT4_MAX_REC_LEN		((1<<16)-1)
2312 
2313 /*
2314  * The rec_len is dependent on the type of directory. Directories that are
2315  * casefolded and encrypted need to store the hash as well, so we add room for
2316  * ext4_extended_dir_entry_2. For all entries related to '.' or '..' you should
2317  * pass NULL for dir, as those entries do not use the extra fields.
2318  */
2319 static inline unsigned int ext4_dir_rec_len(__u8 name_len,
2320 						const struct inode *dir)
2321 {
2322 	int rec_len = (name_len + 8 + EXT4_DIR_ROUND);
2323 
2324 	if (dir && ext4_hash_in_dirent(dir))
2325 		rec_len += sizeof(struct ext4_dir_entry_hash);
2326 	return (rec_len & ~EXT4_DIR_ROUND);
2327 }
2328 
2329 /*
2330  * If we ever get support for fs block sizes > page_size, we'll need
2331  * to remove the #if statements in the next two functions...
2332  */
2333 static inline unsigned int
2334 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
2335 {
2336 	unsigned len = le16_to_cpu(dlen);
2337 
2338 #if (PAGE_SIZE >= 65536)
2339 	if (len == EXT4_MAX_REC_LEN || len == 0)
2340 		return blocksize;
2341 	return (len & 65532) | ((len & 3) << 16);
2342 #else
2343 	return len;
2344 #endif
2345 }
2346 
2347 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2348 {
2349 	BUG_ON((len > blocksize) || (blocksize > (1 << 18)) || (len & 3));
2350 #if (PAGE_SIZE >= 65536)
2351 	if (len < 65536)
2352 		return cpu_to_le16(len);
2353 	if (len == blocksize) {
2354 		if (blocksize == 65536)
2355 			return cpu_to_le16(EXT4_MAX_REC_LEN);
2356 		else
2357 			return cpu_to_le16(0);
2358 	}
2359 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2360 #else
2361 	return cpu_to_le16(len);
2362 #endif
2363 }
2364 
2365 /*
2366  * Hash Tree Directory indexing
2367  * (c) Daniel Phillips, 2001
2368  */
2369 
2370 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2371 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2372 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2373 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2374 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2375 
2376 /* Legal values for the dx_root hash_version field: */
2377 
2378 #define DX_HASH_LEGACY			0
2379 #define DX_HASH_HALF_MD4		1
2380 #define DX_HASH_TEA			2
2381 #define DX_HASH_LEGACY_UNSIGNED		3
2382 #define DX_HASH_HALF_MD4_UNSIGNED	4
2383 #define DX_HASH_TEA_UNSIGNED		5
2384 #define DX_HASH_SIPHASH			6
2385 
2386 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2387 			      const void *address, unsigned int length)
2388 {
2389 	struct {
2390 		struct shash_desc shash;
2391 		char ctx[4];
2392 	} desc;
2393 
2394 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2395 
2396 	desc.shash.tfm = sbi->s_chksum_driver;
2397 	*(u32 *)desc.ctx = crc;
2398 
2399 	BUG_ON(crypto_shash_update(&desc.shash, address, length));
2400 
2401 	return *(u32 *)desc.ctx;
2402 }
2403 
2404 #ifdef __KERNEL__
2405 
2406 /* hash info structure used by the directory hash */
2407 struct dx_hash_info
2408 {
2409 	u32		hash;
2410 	u32		minor_hash;
2411 	int		hash_version;
2412 	u32		*seed;
2413 };
2414 
2415 
2416 /* 32 and 64 bit signed EOF for dx directories */
2417 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2418 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2419 
2420 
2421 /*
2422  * Control parameters used by ext4_htree_next_block
2423  */
2424 #define HASH_NB_ALWAYS		1
2425 
2426 struct ext4_filename {
2427 	const struct qstr *usr_fname;
2428 	struct fscrypt_str disk_name;
2429 	struct dx_hash_info hinfo;
2430 #ifdef CONFIG_FS_ENCRYPTION
2431 	struct fscrypt_str crypto_buf;
2432 #endif
2433 #if IS_ENABLED(CONFIG_UNICODE)
2434 	struct fscrypt_str cf_name;
2435 #endif
2436 };
2437 
2438 #define fname_name(p) ((p)->disk_name.name)
2439 #define fname_usr_name(p) ((p)->usr_fname->name)
2440 #define fname_len(p)  ((p)->disk_name.len)
2441 
2442 /*
2443  * Describe an inode's exact location on disk and in memory
2444  */
2445 struct ext4_iloc
2446 {
2447 	struct buffer_head *bh;
2448 	unsigned long offset;
2449 	ext4_group_t block_group;
2450 };
2451 
2452 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2453 {
2454 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2455 }
2456 
2457 static inline bool ext4_is_quota_file(struct inode *inode)
2458 {
2459 	return IS_NOQUOTA(inode) &&
2460 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2461 }
2462 
2463 /*
2464  * This structure is stuffed into the struct file's private_data field
2465  * for directories.  It is where we put information so that we can do
2466  * readdir operations in hash tree order.
2467  */
2468 struct dir_private_info {
2469 	struct rb_root	root;
2470 	struct rb_node	*curr_node;
2471 	struct fname	*extra_fname;
2472 	loff_t		last_pos;
2473 	__u32		curr_hash;
2474 	__u32		curr_minor_hash;
2475 	__u32		next_hash;
2476 };
2477 
2478 /* calculate the first block number of the group */
2479 static inline ext4_fsblk_t
2480 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2481 {
2482 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2483 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2484 }
2485 
2486 /*
2487  * Special error return code only used by dx_probe() and its callers.
2488  */
2489 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2490 
2491 /* htree levels for ext4 */
2492 #define	EXT4_HTREE_LEVEL_COMPAT	2
2493 #define	EXT4_HTREE_LEVEL	3
2494 
2495 static inline int ext4_dir_htree_level(struct super_block *sb)
2496 {
2497 	return ext4_has_feature_largedir(sb) ?
2498 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2499 }
2500 
2501 /*
2502  * Timeout and state flag for lazy initialization inode thread.
2503  */
2504 #define EXT4_DEF_LI_WAIT_MULT			10
2505 #define EXT4_DEF_LI_MAX_START_DELAY		5
2506 #define EXT4_LAZYINIT_QUIT			0x0001
2507 #define EXT4_LAZYINIT_RUNNING			0x0002
2508 
2509 /*
2510  * Lazy inode table initialization info
2511  */
2512 struct ext4_lazy_init {
2513 	unsigned long		li_state;
2514 	struct list_head	li_request_list;
2515 	struct mutex		li_list_mtx;
2516 };
2517 
2518 enum ext4_li_mode {
2519 	EXT4_LI_MODE_PREFETCH_BBITMAP,
2520 	EXT4_LI_MODE_ITABLE,
2521 };
2522 
2523 struct ext4_li_request {
2524 	struct super_block	*lr_super;
2525 	enum ext4_li_mode	lr_mode;
2526 	ext4_group_t		lr_first_not_zeroed;
2527 	ext4_group_t		lr_next_group;
2528 	struct list_head	lr_request;
2529 	unsigned long		lr_next_sched;
2530 	unsigned long		lr_timeout;
2531 };
2532 
2533 struct ext4_features {
2534 	struct kobject f_kobj;
2535 	struct completion f_kobj_unregister;
2536 };
2537 
2538 /*
2539  * This structure will be used for multiple mount protection. It will be
2540  * written into the block number saved in the s_mmp_block field in the
2541  * superblock. Programs that check MMP should assume that if
2542  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2543  * to use the filesystem, regardless of how old the timestamp is.
2544  */
2545 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2546 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2547 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2548 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2549 
2550 struct mmp_struct {
2551 	__le32	mmp_magic;		/* Magic number for MMP */
2552 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2553 
2554 	/*
2555 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2556 	 * purposes and do not affect the correctness of the algorithm
2557 	 */
2558 	__le64	mmp_time;		/* Time last updated */
2559 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2560 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2561 
2562 	/*
2563 	 * mmp_check_interval is used to verify if the MMP block has been
2564 	 * updated on the block device. The value is updated based on the
2565 	 * maximum time to write the MMP block during an update cycle.
2566 	 */
2567 	__le16	mmp_check_interval;
2568 
2569 	__le16	mmp_pad1;
2570 	__le32	mmp_pad2[226];
2571 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2572 };
2573 
2574 /* arguments passed to the mmp thread */
2575 struct mmpd_data {
2576 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2577 	struct super_block *sb;  /* super block of the fs */
2578 };
2579 
2580 /*
2581  * Check interval multiplier
2582  * The MMP block is written every update interval and initially checked every
2583  * update interval x the multiplier (the value is then adapted based on the
2584  * write latency). The reason is that writes can be delayed under load and we
2585  * don't want readers to incorrectly assume that the filesystem is no longer
2586  * in use.
2587  */
2588 #define EXT4_MMP_CHECK_MULT		2UL
2589 
2590 /*
2591  * Minimum interval for MMP checking in seconds.
2592  */
2593 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2594 
2595 /*
2596  * Maximum interval for MMP checking in seconds.
2597  */
2598 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2599 
2600 /*
2601  * Function prototypes
2602  */
2603 
2604 /*
2605  * Ok, these declarations are also in <linux/kernel.h> but none of the
2606  * ext4 source programs needs to include it so they are duplicated here.
2607  */
2608 # define NORET_TYPE	/**/
2609 # define ATTRIB_NORET	__attribute__((noreturn))
2610 # define NORET_AND	noreturn,
2611 
2612 /* bitmap.c */
2613 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2614 void ext4_inode_bitmap_csum_set(struct super_block *sb,
2615 				struct ext4_group_desc *gdp,
2616 				struct buffer_head *bh, int sz);
2617 int ext4_inode_bitmap_csum_verify(struct super_block *sb,
2618 				  struct ext4_group_desc *gdp,
2619 				  struct buffer_head *bh, int sz);
2620 void ext4_block_bitmap_csum_set(struct super_block *sb,
2621 				struct ext4_group_desc *gdp,
2622 				struct buffer_head *bh);
2623 int ext4_block_bitmap_csum_verify(struct super_block *sb,
2624 				  struct ext4_group_desc *gdp,
2625 				  struct buffer_head *bh);
2626 
2627 /* balloc.c */
2628 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2629 					 ext4_fsblk_t blocknr,
2630 					 ext4_group_t *blockgrpp,
2631 					 ext4_grpblk_t *offsetp);
2632 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2633 					  ext4_fsblk_t block);
2634 
2635 extern unsigned int ext4_block_group(struct super_block *sb,
2636 			ext4_fsblk_t blocknr);
2637 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2638 			ext4_fsblk_t blocknr);
2639 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2640 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2641 			ext4_group_t group);
2642 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2643 					 ext4_fsblk_t goal,
2644 					 unsigned int flags,
2645 					 unsigned long *count,
2646 					 int *errp);
2647 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2648 				    s64 nclusters, unsigned int flags);
2649 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2650 extern void ext4_check_blocks_bitmap(struct super_block *);
2651 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2652 						    ext4_group_t block_group,
2653 						    struct buffer_head ** bh);
2654 extern struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2655 						   ext4_group_t group);
2656 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2657 
2658 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2659 						ext4_group_t block_group,
2660 						bool ignore_locked);
2661 extern int ext4_wait_block_bitmap(struct super_block *sb,
2662 				  ext4_group_t block_group,
2663 				  struct buffer_head *bh);
2664 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2665 						  ext4_group_t block_group);
2666 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2667 					      ext4_group_t block_group,
2668 					      struct ext4_group_desc *gdp);
2669 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2670 
2671 #if IS_ENABLED(CONFIG_UNICODE)
2672 extern int ext4_fname_setup_ci_filename(struct inode *dir,
2673 					 const struct qstr *iname,
2674 					 struct ext4_filename *fname);
2675 #endif
2676 
2677 /* ext4 encryption related stuff goes here crypto.c */
2678 #ifdef CONFIG_FS_ENCRYPTION
2679 extern const struct fscrypt_operations ext4_cryptops;
2680 
2681 int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
2682 			      int lookup, struct ext4_filename *fname);
2683 
2684 int ext4_fname_prepare_lookup(struct inode *dir, struct dentry *dentry,
2685 			      struct ext4_filename *fname);
2686 
2687 void ext4_fname_free_filename(struct ext4_filename *fname);
2688 
2689 int ext4_ioctl_get_encryption_pwsalt(struct file *filp, void __user *arg);
2690 
2691 #else /* !CONFIG_FS_ENCRYPTION */
2692 static inline int ext4_fname_setup_filename(struct inode *dir,
2693 					    const struct qstr *iname,
2694 					    int lookup,
2695 					    struct ext4_filename *fname)
2696 {
2697 	int err = 0;
2698 	fname->usr_fname = iname;
2699 	fname->disk_name.name = (unsigned char *) iname->name;
2700 	fname->disk_name.len = iname->len;
2701 
2702 #if IS_ENABLED(CONFIG_UNICODE)
2703 	err = ext4_fname_setup_ci_filename(dir, iname, fname);
2704 #endif
2705 
2706 	return err;
2707 }
2708 
2709 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2710 					    struct dentry *dentry,
2711 					    struct ext4_filename *fname)
2712 {
2713 	return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
2714 }
2715 
2716 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2717 {
2718 #if IS_ENABLED(CONFIG_UNICODE)
2719 	kfree(fname->cf_name.name);
2720 	fname->cf_name.name = NULL;
2721 #endif
2722 }
2723 
2724 static inline int ext4_ioctl_get_encryption_pwsalt(struct file *filp,
2725 						   void __user *arg)
2726 {
2727 	return -EOPNOTSUPP;
2728 }
2729 #endif /* !CONFIG_FS_ENCRYPTION */
2730 
2731 /* dir.c */
2732 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2733 				  struct file *,
2734 				  struct ext4_dir_entry_2 *,
2735 				  struct buffer_head *, char *, int,
2736 				  unsigned int);
2737 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset) \
2738 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2739 				(de), (bh), (buf), (size), (offset)))
2740 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2741 				__u32 minor_hash,
2742 				struct ext4_dir_entry_2 *dirent,
2743 				struct fscrypt_str *ent_name);
2744 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2745 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2746 			     struct buffer_head *bh,
2747 			     void *buf, int buf_size,
2748 			     struct ext4_filename *fname,
2749 			     struct ext4_dir_entry_2 **dest_de);
2750 void ext4_insert_dentry(struct inode *dir, struct inode *inode,
2751 			struct ext4_dir_entry_2 *de,
2752 			int buf_size,
2753 			struct ext4_filename *fname);
2754 static inline void ext4_update_dx_flag(struct inode *inode)
2755 {
2756 	if (!ext4_has_feature_dir_index(inode->i_sb) &&
2757 	    ext4_test_inode_flag(inode, EXT4_INODE_INDEX)) {
2758 		/* ext4_iget() should have caught this... */
2759 		WARN_ON_ONCE(ext4_has_feature_metadata_csum(inode->i_sb));
2760 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2761 	}
2762 }
2763 static const unsigned char ext4_filetype_table[] = {
2764 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2765 };
2766 
2767 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2768 {
2769 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2770 		return DT_UNKNOWN;
2771 
2772 	return ext4_filetype_table[filetype];
2773 }
2774 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2775 			     void *buf, int buf_size);
2776 
2777 /* fsync.c */
2778 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2779 
2780 /* hash.c */
2781 extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
2782 			  struct dx_hash_info *hinfo);
2783 
2784 /* ialloc.c */
2785 extern int ext4_mark_inode_used(struct super_block *sb, int ino);
2786 extern struct inode *__ext4_new_inode(struct mnt_idmap *, handle_t *,
2787 				      struct inode *, umode_t,
2788 				      const struct qstr *qstr, __u32 goal,
2789 				      uid_t *owner, __u32 i_flags,
2790 				      int handle_type, unsigned int line_no,
2791 				      int nblocks);
2792 
2793 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags)          \
2794 	__ext4_new_inode(&nop_mnt_idmap, (handle), (dir), (mode), (qstr),      \
2795 			 (goal), (owner), i_flags, 0, 0, 0)
2796 #define ext4_new_inode_start_handle(idmap, dir, mode, qstr, goal, owner, \
2797 				    type, nblocks)		    \
2798 	__ext4_new_inode((idmap), NULL, (dir), (mode), (qstr), (goal), (owner), \
2799 			 0, (type), __LINE__, (nblocks))
2800 
2801 
2802 extern void ext4_free_inode(handle_t *, struct inode *);
2803 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2804 extern unsigned long ext4_count_free_inodes(struct super_block *);
2805 extern unsigned long ext4_count_dirs(struct super_block *);
2806 extern void ext4_check_inodes_bitmap(struct super_block *);
2807 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2808 extern int ext4_init_inode_table(struct super_block *sb,
2809 				 ext4_group_t group, int barrier);
2810 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2811 
2812 /* fast_commit.c */
2813 int ext4_fc_info_show(struct seq_file *seq, void *v);
2814 void ext4_fc_init(struct super_block *sb, journal_t *journal);
2815 void ext4_fc_init_inode(struct inode *inode);
2816 void ext4_fc_track_range(handle_t *handle, struct inode *inode, ext4_lblk_t start,
2817 			 ext4_lblk_t end);
2818 void __ext4_fc_track_unlink(handle_t *handle, struct inode *inode,
2819 	struct dentry *dentry);
2820 void __ext4_fc_track_link(handle_t *handle, struct inode *inode,
2821 	struct dentry *dentry);
2822 void ext4_fc_track_unlink(handle_t *handle, struct dentry *dentry);
2823 void ext4_fc_track_link(handle_t *handle, struct dentry *dentry);
2824 void __ext4_fc_track_create(handle_t *handle, struct inode *inode,
2825 			    struct dentry *dentry);
2826 void ext4_fc_track_create(handle_t *handle, struct dentry *dentry);
2827 void ext4_fc_track_inode(handle_t *handle, struct inode *inode);
2828 void ext4_fc_mark_ineligible(struct super_block *sb, int reason, handle_t *handle);
2829 void ext4_fc_start_update(struct inode *inode);
2830 void ext4_fc_stop_update(struct inode *inode);
2831 void ext4_fc_del(struct inode *inode);
2832 bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block);
2833 void ext4_fc_replay_cleanup(struct super_block *sb);
2834 int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
2835 int __init ext4_fc_init_dentry_cache(void);
2836 void ext4_fc_destroy_dentry_cache(void);
2837 int ext4_fc_record_regions(struct super_block *sb, int ino,
2838 			   ext4_lblk_t lblk, ext4_fsblk_t pblk,
2839 			   int len, int replay);
2840 
2841 /* mballoc.c */
2842 extern const struct seq_operations ext4_mb_seq_groups_ops;
2843 extern const struct seq_operations ext4_mb_seq_structs_summary_ops;
2844 extern long ext4_mb_stats;
2845 extern long ext4_mb_max_to_scan;
2846 extern int ext4_seq_mb_stats_show(struct seq_file *seq, void *offset);
2847 extern int ext4_mb_init(struct super_block *);
2848 extern int ext4_mb_release(struct super_block *);
2849 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2850 				struct ext4_allocation_request *, int *);
2851 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2852 extern void ext4_discard_preallocations(struct inode *, unsigned int);
2853 extern int __init ext4_init_mballoc(void);
2854 extern void ext4_exit_mballoc(void);
2855 extern ext4_group_t ext4_mb_prefetch(struct super_block *sb,
2856 				     ext4_group_t group,
2857 				     unsigned int nr, int *cnt);
2858 extern void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group,
2859 				  unsigned int nr);
2860 
2861 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2862 			     struct buffer_head *bh, ext4_fsblk_t block,
2863 			     unsigned long count, int flags);
2864 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2865 				   ext4_group_t ngroups);
2866 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2867 		ext4_group_t i, struct ext4_group_desc *desc);
2868 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2869 				ext4_fsblk_t block, unsigned long count);
2870 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2871 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2872 extern void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block,
2873 		       int len, int state);
2874 
2875 /* inode.c */
2876 void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
2877 			 struct ext4_inode_info *ei);
2878 int ext4_inode_is_fast_symlink(struct inode *inode);
2879 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2880 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2881 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2882 		     bool wait, struct buffer_head **bhs);
2883 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2884 			     struct buffer_head *bh_result, int create);
2885 int ext4_get_block(struct inode *inode, sector_t iblock,
2886 		   struct buffer_head *bh_result, int create);
2887 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2888 			   struct buffer_head *bh, int create);
2889 int ext4_walk_page_buffers(handle_t *handle,
2890 			   struct inode *inode,
2891 			   struct buffer_head *head,
2892 			   unsigned from,
2893 			   unsigned to,
2894 			   int *partial,
2895 			   int (*fn)(handle_t *handle, struct inode *inode,
2896 				     struct buffer_head *bh));
2897 int do_journal_get_write_access(handle_t *handle, struct inode *inode,
2898 				struct buffer_head *bh);
2899 #define FALL_BACK_TO_NONDELALLOC 1
2900 #define CONVERT_INLINE_DATA	 2
2901 
2902 typedef enum {
2903 	EXT4_IGET_NORMAL =	0,
2904 	EXT4_IGET_SPECIAL =	0x0001, /* OK to iget a system inode */
2905 	EXT4_IGET_HANDLE = 	0x0002,	/* Inode # is from a handle */
2906 	EXT4_IGET_BAD =		0x0004, /* Allow to iget a bad inode */
2907 	EXT4_IGET_EA_INODE =	0x0008	/* Inode should contain an EA value */
2908 } ext4_iget_flags;
2909 
2910 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2911 				 ext4_iget_flags flags, const char *function,
2912 				 unsigned int line);
2913 
2914 #define ext4_iget(sb, ino, flags) \
2915 	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2916 
2917 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2918 extern int  ext4_setattr(struct mnt_idmap *, struct dentry *,
2919 			 struct iattr *);
2920 extern u32  ext4_dio_alignment(struct inode *inode);
2921 extern int  ext4_getattr(struct mnt_idmap *, const struct path *,
2922 			 struct kstat *, u32, unsigned int);
2923 extern void ext4_evict_inode(struct inode *);
2924 extern void ext4_clear_inode(struct inode *);
2925 extern int  ext4_file_getattr(struct mnt_idmap *, const struct path *,
2926 			      struct kstat *, u32, unsigned int);
2927 extern int  ext4_sync_inode(handle_t *, struct inode *);
2928 extern void ext4_dirty_inode(struct inode *, int);
2929 extern int ext4_change_inode_journal_flag(struct inode *, int);
2930 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2931 extern int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino,
2932 			  struct ext4_iloc *iloc);
2933 extern int ext4_inode_attach_jinode(struct inode *inode);
2934 extern int ext4_can_truncate(struct inode *inode);
2935 extern int ext4_truncate(struct inode *);
2936 extern int ext4_break_layouts(struct inode *);
2937 extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
2938 extern void ext4_set_inode_flags(struct inode *, bool init);
2939 extern int ext4_alloc_da_blocks(struct inode *inode);
2940 extern void ext4_set_aops(struct inode *inode);
2941 extern int ext4_writepage_trans_blocks(struct inode *);
2942 extern int ext4_normal_submit_inode_data_buffers(struct jbd2_inode *jinode);
2943 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2944 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2945 			     loff_t lstart, loff_t lend);
2946 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
2947 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2948 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2949 extern void ext4_da_release_space(struct inode *inode, int to_free);
2950 extern void ext4_da_update_reserve_space(struct inode *inode,
2951 					int used, int quota_claim);
2952 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2953 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2954 
2955 /* indirect.c */
2956 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2957 				struct ext4_map_blocks *map, int flags);
2958 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2959 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2960 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2961 				 ext4_lblk_t start, ext4_lblk_t end);
2962 
2963 /* ioctl.c */
2964 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2965 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2966 int ext4_fileattr_set(struct mnt_idmap *idmap,
2967 		      struct dentry *dentry, struct fileattr *fa);
2968 int ext4_fileattr_get(struct dentry *dentry, struct fileattr *fa);
2969 extern void ext4_reset_inode_seed(struct inode *inode);
2970 int ext4_update_overhead(struct super_block *sb, bool force);
2971 
2972 /* migrate.c */
2973 extern int ext4_ext_migrate(struct inode *);
2974 extern int ext4_ind_migrate(struct inode *inode);
2975 
2976 /* namei.c */
2977 extern int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2978 			     struct inode *inode);
2979 extern int ext4_dirblock_csum_verify(struct inode *inode,
2980 				     struct buffer_head *bh);
2981 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2982 				__u32 start_minor_hash, __u32 *next_hash);
2983 extern int ext4_search_dir(struct buffer_head *bh,
2984 			   char *search_buf,
2985 			   int buf_size,
2986 			   struct inode *dir,
2987 			   struct ext4_filename *fname,
2988 			   unsigned int offset,
2989 			   struct ext4_dir_entry_2 **res_dir);
2990 extern int ext4_generic_delete_entry(struct inode *dir,
2991 				     struct ext4_dir_entry_2 *de_del,
2992 				     struct buffer_head *bh,
2993 				     void *entry_buf,
2994 				     int buf_size,
2995 				     int csum_size);
2996 extern bool ext4_empty_dir(struct inode *inode);
2997 
2998 /* resize.c */
2999 extern void ext4_kvfree_array_rcu(void *to_free);
3000 extern int ext4_group_add(struct super_block *sb,
3001 				struct ext4_new_group_data *input);
3002 extern int ext4_group_extend(struct super_block *sb,
3003 				struct ext4_super_block *es,
3004 				ext4_fsblk_t n_blocks_count);
3005 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
3006 extern unsigned int ext4_list_backups(struct super_block *sb,
3007 				      unsigned int *three, unsigned int *five,
3008 				      unsigned int *seven);
3009 
3010 /* super.c */
3011 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
3012 					 sector_t block, blk_opf_t op_flags);
3013 extern struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
3014 						   sector_t block);
3015 extern void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
3016 				bh_end_io_t *end_io);
3017 extern int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
3018 			bh_end_io_t *end_io);
3019 extern int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait);
3020 extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
3021 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
3022 extern int ext4_calculate_overhead(struct super_block *sb);
3023 extern __le32 ext4_superblock_csum(struct super_block *sb,
3024 				   struct ext4_super_block *es);
3025 extern void ext4_superblock_csum_set(struct super_block *sb);
3026 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
3027 				    ext4_group_t ngroup);
3028 extern const char *ext4_decode_error(struct super_block *sb, int errno,
3029 				     char nbuf[16]);
3030 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
3031 					     ext4_group_t block_group,
3032 					     unsigned int flags);
3033 
3034 extern __printf(7, 8)
3035 void __ext4_error(struct super_block *, const char *, unsigned int, bool,
3036 		  int, __u64, const char *, ...);
3037 extern __printf(6, 7)
3038 void __ext4_error_inode(struct inode *, const char *, unsigned int,
3039 			ext4_fsblk_t, int, const char *, ...);
3040 extern __printf(5, 6)
3041 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
3042 		     const char *, ...);
3043 extern void __ext4_std_error(struct super_block *, const char *,
3044 			     unsigned int, int);
3045 extern __printf(4, 5)
3046 void __ext4_warning(struct super_block *, const char *, unsigned int,
3047 		    const char *, ...);
3048 extern __printf(4, 5)
3049 void __ext4_warning_inode(const struct inode *inode, const char *function,
3050 			  unsigned int line, const char *fmt, ...);
3051 extern __printf(3, 4)
3052 void __ext4_msg(struct super_block *, const char *, const char *, ...);
3053 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
3054 			   const char *, unsigned int, const char *);
3055 extern __printf(7, 8)
3056 void __ext4_grp_locked_error(const char *, unsigned int,
3057 			     struct super_block *, ext4_group_t,
3058 			     unsigned long, ext4_fsblk_t,
3059 			     const char *, ...);
3060 
3061 #define EXT4_ERROR_INODE(inode, fmt, a...) \
3062 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
3063 
3064 #define EXT4_ERROR_INODE_ERR(inode, err, fmt, a...)			\
3065 	__ext4_error_inode((inode), __func__, __LINE__, 0, (err), (fmt), ## a)
3066 
3067 #define ext4_error_inode_block(inode, block, err, fmt, a...)		\
3068 	__ext4_error_inode((inode), __func__, __LINE__, (block), (err),	\
3069 			   (fmt), ## a)
3070 
3071 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
3072 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
3073 
3074 #define ext4_abort(sb, err, fmt, a...)					\
3075 	__ext4_error((sb), __func__, __LINE__, true, (err), 0, (fmt), ## a)
3076 
3077 #ifdef CONFIG_PRINTK
3078 
3079 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
3080 	__ext4_error_inode(inode, func, line, block, 0, fmt, ##__VA_ARGS__)
3081 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
3082 	__ext4_error_inode((inode), (func), (line), (block), 		\
3083 			   (err), (fmt), ##__VA_ARGS__)
3084 #define ext4_error_file(file, func, line, block, fmt, ...)		\
3085 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
3086 #define ext4_error(sb, fmt, ...)					\
3087 	__ext4_error((sb), __func__, __LINE__, false, 0, 0, (fmt),	\
3088 		##__VA_ARGS__)
3089 #define ext4_error_err(sb, err, fmt, ...)				\
3090 	__ext4_error((sb), __func__, __LINE__, false, (err), 0, (fmt),	\
3091 		##__VA_ARGS__)
3092 #define ext4_warning(sb, fmt, ...)					\
3093 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
3094 #define ext4_warning_inode(inode, fmt, ...)				\
3095 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
3096 #define ext4_msg(sb, level, fmt, ...)				\
3097 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
3098 #define dump_mmp_msg(sb, mmp, msg)					\
3099 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
3100 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
3101 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
3102 				fmt, ##__VA_ARGS__)
3103 
3104 #else
3105 
3106 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
3107 do {									\
3108 	no_printk(fmt, ##__VA_ARGS__);					\
3109 	__ext4_error_inode(inode, "", 0, block, 0, " ");		\
3110 } while (0)
3111 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
3112 do {									\
3113 	no_printk(fmt, ##__VA_ARGS__);					\
3114 	__ext4_error_inode(inode, "", 0, block, err, " ");		\
3115 } while (0)
3116 #define ext4_error_file(file, func, line, block, fmt, ...)		\
3117 do {									\
3118 	no_printk(fmt, ##__VA_ARGS__);					\
3119 	__ext4_error_file(file, "", 0, block, " ");			\
3120 } while (0)
3121 #define ext4_error(sb, fmt, ...)					\
3122 do {									\
3123 	no_printk(fmt, ##__VA_ARGS__);					\
3124 	__ext4_error(sb, "", 0, false, 0, 0, " ");			\
3125 } while (0)
3126 #define ext4_error_err(sb, err, fmt, ...)				\
3127 do {									\
3128 	no_printk(fmt, ##__VA_ARGS__);					\
3129 	__ext4_error(sb, "", 0, false, err, 0, " ");			\
3130 } while (0)
3131 #define ext4_warning(sb, fmt, ...)					\
3132 do {									\
3133 	no_printk(fmt, ##__VA_ARGS__);					\
3134 	__ext4_warning(sb, "", 0, " ");					\
3135 } while (0)
3136 #define ext4_warning_inode(inode, fmt, ...)				\
3137 do {									\
3138 	no_printk(fmt, ##__VA_ARGS__);					\
3139 	__ext4_warning_inode(inode, "", 0, " ");			\
3140 } while (0)
3141 #define ext4_msg(sb, level, fmt, ...)					\
3142 do {									\
3143 	no_printk(fmt, ##__VA_ARGS__);					\
3144 	__ext4_msg(sb, "", " ");					\
3145 } while (0)
3146 #define dump_mmp_msg(sb, mmp, msg)					\
3147 	__dump_mmp_msg(sb, mmp, "", 0, "")
3148 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
3149 do {									\
3150 	no_printk(fmt, ##__VA_ARGS__);				\
3151 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
3152 } while (0)
3153 
3154 #endif
3155 
3156 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
3157 				      struct ext4_group_desc *bg);
3158 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
3159 				      struct ext4_group_desc *bg);
3160 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
3161 				     struct ext4_group_desc *bg);
3162 extern __u32 ext4_free_group_clusters(struct super_block *sb,
3163 				      struct ext4_group_desc *bg);
3164 extern __u32 ext4_free_inodes_count(struct super_block *sb,
3165 				 struct ext4_group_desc *bg);
3166 extern __u32 ext4_used_dirs_count(struct super_block *sb,
3167 				struct ext4_group_desc *bg);
3168 extern __u32 ext4_itable_unused_count(struct super_block *sb,
3169 				   struct ext4_group_desc *bg);
3170 extern void ext4_block_bitmap_set(struct super_block *sb,
3171 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3172 extern void ext4_inode_bitmap_set(struct super_block *sb,
3173 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3174 extern void ext4_inode_table_set(struct super_block *sb,
3175 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
3176 extern void ext4_free_group_clusters_set(struct super_block *sb,
3177 					 struct ext4_group_desc *bg,
3178 					 __u32 count);
3179 extern void ext4_free_inodes_set(struct super_block *sb,
3180 				struct ext4_group_desc *bg, __u32 count);
3181 extern void ext4_used_dirs_set(struct super_block *sb,
3182 				struct ext4_group_desc *bg, __u32 count);
3183 extern void ext4_itable_unused_set(struct super_block *sb,
3184 				   struct ext4_group_desc *bg, __u32 count);
3185 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
3186 				       struct ext4_group_desc *gdp);
3187 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
3188 				     struct ext4_group_desc *gdp);
3189 extern int ext4_register_li_request(struct super_block *sb,
3190 				    ext4_group_t first_not_zeroed);
3191 
3192 static inline int ext4_has_metadata_csum(struct super_block *sb)
3193 {
3194 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
3195 		     !EXT4_SB(sb)->s_chksum_driver);
3196 
3197 	return ext4_has_feature_metadata_csum(sb) &&
3198 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
3199 }
3200 
3201 static inline int ext4_has_group_desc_csum(struct super_block *sb)
3202 {
3203 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
3204 }
3205 
3206 #define ext4_read_incompat_64bit_val(es, name) \
3207 	(((es)->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT) \
3208 		? (ext4_fsblk_t)le32_to_cpu(es->name##_hi) << 32 : 0) | \
3209 		le32_to_cpu(es->name##_lo))
3210 
3211 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
3212 {
3213 	return ext4_read_incompat_64bit_val(es, s_blocks_count);
3214 }
3215 
3216 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
3217 {
3218 	return ext4_read_incompat_64bit_val(es, s_r_blocks_count);
3219 }
3220 
3221 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
3222 {
3223 	return ext4_read_incompat_64bit_val(es, s_free_blocks_count);
3224 }
3225 
3226 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
3227 					 ext4_fsblk_t blk)
3228 {
3229 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
3230 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
3231 }
3232 
3233 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
3234 					      ext4_fsblk_t blk)
3235 {
3236 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
3237 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
3238 }
3239 
3240 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
3241 					   ext4_fsblk_t blk)
3242 {
3243 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
3244 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
3245 }
3246 
3247 static inline loff_t ext4_isize(struct super_block *sb,
3248 				struct ext4_inode *raw_inode)
3249 {
3250 	if (ext4_has_feature_largedir(sb) ||
3251 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
3252 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
3253 			le32_to_cpu(raw_inode->i_size_lo);
3254 
3255 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
3256 }
3257 
3258 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
3259 {
3260 	raw_inode->i_size_lo = cpu_to_le32(i_size);
3261 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
3262 }
3263 
3264 /*
3265  * Reading s_groups_count requires using smp_rmb() afterwards.  See
3266  * the locking protocol documented in the comments of ext4_group_add()
3267  * in resize.c
3268  */
3269 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
3270 {
3271 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
3272 
3273 	smp_rmb();
3274 	return ngroups;
3275 }
3276 
3277 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
3278 					     ext4_group_t block_group)
3279 {
3280 	return block_group >> sbi->s_log_groups_per_flex;
3281 }
3282 
3283 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
3284 {
3285 	return 1 << sbi->s_log_groups_per_flex;
3286 }
3287 
3288 #define ext4_std_error(sb, errno)				\
3289 do {								\
3290 	if ((errno))						\
3291 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
3292 } while (0)
3293 
3294 #ifdef CONFIG_SMP
3295 /* Each CPU can accumulate percpu_counter_batch clusters in their local
3296  * counters. So we need to make sure we have free clusters more
3297  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
3298  */
3299 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
3300 #else
3301 #define EXT4_FREECLUSTERS_WATERMARK 0
3302 #endif
3303 
3304 /* Update i_disksize. Requires i_rwsem to avoid races with truncate */
3305 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
3306 {
3307 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
3308 		     !inode_is_locked(inode));
3309 	down_write(&EXT4_I(inode)->i_data_sem);
3310 	if (newsize > EXT4_I(inode)->i_disksize)
3311 		WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
3312 	up_write(&EXT4_I(inode)->i_data_sem);
3313 }
3314 
3315 /* Update i_size, i_disksize. Requires i_rwsem to avoid races with truncate */
3316 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
3317 {
3318 	int changed = 0;
3319 
3320 	if (newsize > inode->i_size) {
3321 		i_size_write(inode, newsize);
3322 		changed = 1;
3323 	}
3324 	if (newsize > EXT4_I(inode)->i_disksize) {
3325 		ext4_update_i_disksize(inode, newsize);
3326 		changed |= 2;
3327 	}
3328 	return changed;
3329 }
3330 
3331 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
3332 				      loff_t len);
3333 
3334 struct ext4_group_info {
3335 	unsigned long   bb_state;
3336 #ifdef AGGRESSIVE_CHECK
3337 	unsigned long	bb_check_counter;
3338 #endif
3339 	struct rb_root  bb_free_root;
3340 	ext4_grpblk_t	bb_first_free;	/* first free block */
3341 	ext4_grpblk_t	bb_free;	/* total free blocks */
3342 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
3343 	int		bb_avg_fragment_size_order;	/* order of average
3344 							   fragment in BG */
3345 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
3346 	ext4_group_t	bb_group;	/* Group number */
3347 	struct          list_head bb_prealloc_list;
3348 #ifdef DOUBLE_CHECK
3349 	void            *bb_bitmap;
3350 #endif
3351 	struct rw_semaphore alloc_sem;
3352 	struct list_head bb_avg_fragment_size_node;
3353 	struct list_head bb_largest_free_order_node;
3354 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
3355 					 * regions, index is order.
3356 					 * bb_counters[3] = 5 means
3357 					 * 5 free 8-block regions. */
3358 };
3359 
3360 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
3361 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
3362 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
3363 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
3364 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT		\
3365 	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
3366 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT		\
3367 	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
3368 #define EXT4_GROUP_INFO_BBITMAP_READ_BIT	4
3369 
3370 #define EXT4_MB_GRP_NEED_INIT(grp)	\
3371 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
3372 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
3373 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3374 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
3375 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3376 
3377 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
3378 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3379 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
3380 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3381 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
3382 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3383 #define EXT4_MB_GRP_TEST_AND_SET_READ(grp)	\
3384 	(test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_READ_BIT, &((grp)->bb_state)))
3385 
3386 #define EXT4_MAX_CONTENTION		8
3387 #define EXT4_CONTENTION_THRESHOLD	2
3388 
3389 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
3390 					      ext4_group_t group)
3391 {
3392 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
3393 }
3394 
3395 /*
3396  * Returns true if the filesystem is busy enough that attempts to
3397  * access the block group locks has run into contention.
3398  */
3399 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
3400 {
3401 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
3402 }
3403 
3404 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
3405 {
3406 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
3407 	if (spin_trylock(lock))
3408 		/*
3409 		 * We're able to grab the lock right away, so drop the
3410 		 * lock contention counter.
3411 		 */
3412 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
3413 	else {
3414 		/*
3415 		 * The lock is busy, so bump the contention counter,
3416 		 * and then wait on the spin lock.
3417 		 */
3418 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
3419 				  EXT4_MAX_CONTENTION);
3420 		spin_lock(lock);
3421 	}
3422 }
3423 
3424 static inline void ext4_unlock_group(struct super_block *sb,
3425 					ext4_group_t group)
3426 {
3427 	spin_unlock(ext4_group_lock_ptr(sb, group));
3428 }
3429 
3430 #ifdef CONFIG_QUOTA
3431 static inline bool ext4_quota_capable(struct super_block *sb)
3432 {
3433 	return (test_opt(sb, QUOTA) || ext4_has_feature_quota(sb));
3434 }
3435 
3436 static inline bool ext4_is_quota_journalled(struct super_block *sb)
3437 {
3438 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3439 
3440 	return (ext4_has_feature_quota(sb) ||
3441 		sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]);
3442 }
3443 int ext4_enable_quotas(struct super_block *sb);
3444 #endif
3445 
3446 /*
3447  * Block validity checking
3448  */
3449 #define ext4_check_indirect_blockref(inode, bh)				\
3450 	ext4_check_blockref(__func__, __LINE__, inode,			\
3451 			    (__le32 *)(bh)->b_data,			\
3452 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3453 
3454 #define ext4_ind_check_inode(inode)					\
3455 	ext4_check_blockref(__func__, __LINE__, inode,			\
3456 			    EXT4_I(inode)->i_data,			\
3457 			    EXT4_NDIR_BLOCKS)
3458 
3459 /*
3460  * Inodes and files operations
3461  */
3462 
3463 /* dir.c */
3464 extern const struct file_operations ext4_dir_operations;
3465 
3466 /* file.c */
3467 extern const struct inode_operations ext4_file_inode_operations;
3468 extern const struct file_operations ext4_file_operations;
3469 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
3470 
3471 /* inline.c */
3472 extern int ext4_get_max_inline_size(struct inode *inode);
3473 extern int ext4_find_inline_data_nolock(struct inode *inode);
3474 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
3475 				 unsigned int len);
3476 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3477 
3478 int ext4_readpage_inline(struct inode *inode, struct folio *folio);
3479 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3480 					 struct inode *inode,
3481 					 loff_t pos, unsigned len,
3482 					 struct page **pagep);
3483 extern int ext4_write_inline_data_end(struct inode *inode,
3484 				      loff_t pos, unsigned len,
3485 				      unsigned copied,
3486 				      struct page *page);
3487 extern struct buffer_head *
3488 ext4_journalled_write_inline_data(struct inode *inode,
3489 				  unsigned len,
3490 				  struct page *page);
3491 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3492 					   struct inode *inode,
3493 					   loff_t pos, unsigned len,
3494 					   struct page **pagep,
3495 					   void **fsdata);
3496 extern int ext4_try_add_inline_entry(handle_t *handle,
3497 				     struct ext4_filename *fname,
3498 				     struct inode *dir, struct inode *inode);
3499 extern int ext4_try_create_inline_dir(handle_t *handle,
3500 				      struct inode *parent,
3501 				      struct inode *inode);
3502 extern int ext4_read_inline_dir(struct file *filp,
3503 				struct dir_context *ctx,
3504 				int *has_inline_data);
3505 extern int ext4_inlinedir_to_tree(struct file *dir_file,
3506 				  struct inode *dir, ext4_lblk_t block,
3507 				  struct dx_hash_info *hinfo,
3508 				  __u32 start_hash, __u32 start_minor_hash,
3509 				  int *has_inline_data);
3510 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3511 					struct ext4_filename *fname,
3512 					struct ext4_dir_entry_2 **res_dir,
3513 					int *has_inline_data);
3514 extern int ext4_delete_inline_entry(handle_t *handle,
3515 				    struct inode *dir,
3516 				    struct ext4_dir_entry_2 *de_del,
3517 				    struct buffer_head *bh,
3518 				    int *has_inline_data);
3519 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3520 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3521 					struct ext4_dir_entry_2 **parent_de,
3522 					int *retval);
3523 extern void *ext4_read_inline_link(struct inode *inode);
3524 
3525 struct iomap;
3526 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3527 
3528 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3529 
3530 extern int ext4_convert_inline_data(struct inode *inode);
3531 
3532 static inline int ext4_has_inline_data(struct inode *inode)
3533 {
3534 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3535 	       EXT4_I(inode)->i_inline_off;
3536 }
3537 
3538 /* namei.c */
3539 extern const struct inode_operations ext4_dir_inode_operations;
3540 extern const struct inode_operations ext4_special_inode_operations;
3541 extern struct dentry *ext4_get_parent(struct dentry *child);
3542 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3543 				 struct ext4_dir_entry_2 *de,
3544 				 int blocksize, int csum_size,
3545 				 unsigned int parent_ino, int dotdot_real_len);
3546 extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
3547 					unsigned int blocksize);
3548 extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
3549 				      struct buffer_head *bh);
3550 extern int __ext4_unlink(struct inode *dir, const struct qstr *d_name,
3551 			 struct inode *inode, struct dentry *dentry);
3552 extern int __ext4_link(struct inode *dir, struct inode *inode,
3553 		       struct dentry *dentry);
3554 
3555 #define S_SHIFT 12
3556 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3557 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3558 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3559 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3560 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3561 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3562 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3563 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3564 };
3565 
3566 static inline void ext4_set_de_type(struct super_block *sb,
3567 				struct ext4_dir_entry_2 *de,
3568 				umode_t mode) {
3569 	if (ext4_has_feature_filetype(sb))
3570 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3571 }
3572 
3573 /* readpages.c */
3574 extern int ext4_mpage_readpages(struct inode *inode,
3575 		struct readahead_control *rac, struct folio *folio);
3576 extern int __init ext4_init_post_read_processing(void);
3577 extern void ext4_exit_post_read_processing(void);
3578 
3579 /* symlink.c */
3580 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3581 extern const struct inode_operations ext4_symlink_inode_operations;
3582 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3583 
3584 /* sysfs.c */
3585 extern void ext4_notify_error_sysfs(struct ext4_sb_info *sbi);
3586 extern int ext4_register_sysfs(struct super_block *sb);
3587 extern void ext4_unregister_sysfs(struct super_block *sb);
3588 extern int __init ext4_init_sysfs(void);
3589 extern void ext4_exit_sysfs(void);
3590 
3591 /* block_validity */
3592 extern void ext4_release_system_zone(struct super_block *sb);
3593 extern int ext4_setup_system_zone(struct super_block *sb);
3594 extern int __init ext4_init_system_zone(void);
3595 extern void ext4_exit_system_zone(void);
3596 extern int ext4_inode_block_valid(struct inode *inode,
3597 				  ext4_fsblk_t start_blk,
3598 				  unsigned int count);
3599 extern int ext4_check_blockref(const char *, unsigned int,
3600 			       struct inode *, __le32 *, unsigned int);
3601 extern int ext4_sb_block_valid(struct super_block *sb, struct inode *inode,
3602 				ext4_fsblk_t start_blk, unsigned int count);
3603 
3604 
3605 /* extents.c */
3606 struct ext4_ext_path;
3607 struct ext4_extent;
3608 
3609 /*
3610  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3611  * __le32.
3612  */
3613 #define EXT_MAX_BLOCKS	0xffffffff
3614 
3615 extern void ext4_ext_tree_init(handle_t *handle, struct inode *inode);
3616 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3617 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3618 			       struct ext4_map_blocks *map, int flags);
3619 extern int ext4_ext_truncate(handle_t *, struct inode *);
3620 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3621 				 ext4_lblk_t end);
3622 extern void ext4_ext_init(struct super_block *);
3623 extern void ext4_ext_release(struct super_block *);
3624 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3625 			  loff_t len);
3626 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3627 					  loff_t offset, ssize_t len);
3628 extern int ext4_convert_unwritten_io_end_vec(handle_t *handle,
3629 					     ext4_io_end_t *io_end);
3630 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3631 			   struct ext4_map_blocks *map, int flags);
3632 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3633 						   int num,
3634 						   struct ext4_ext_path *path);
3635 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3636 				  struct ext4_ext_path **,
3637 				  struct ext4_extent *, int);
3638 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3639 					      struct ext4_ext_path **,
3640 					      int flags);
3641 extern void ext4_free_ext_path(struct ext4_ext_path *);
3642 extern int ext4_ext_check_inode(struct inode *inode);
3643 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3644 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3645 			__u64 start, __u64 len);
3646 extern int ext4_get_es_cache(struct inode *inode,
3647 			     struct fiemap_extent_info *fieinfo,
3648 			     __u64 start, __u64 len);
3649 extern int ext4_ext_precache(struct inode *inode);
3650 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3651 				struct inode *inode2, ext4_lblk_t lblk1,
3652 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3653 			     int mark_unwritten,int *err);
3654 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3655 extern int ext4_datasem_ensure_credits(handle_t *handle, struct inode *inode,
3656 				       int check_cred, int restart_cred,
3657 				       int revoke_cred);
3658 extern void ext4_ext_replay_shrink_inode(struct inode *inode, ext4_lblk_t end);
3659 extern int ext4_ext_replay_set_iblocks(struct inode *inode);
3660 extern int ext4_ext_replay_update_ex(struct inode *inode, ext4_lblk_t start,
3661 		int len, int unwritten, ext4_fsblk_t pblk);
3662 extern int ext4_ext_clear_bb(struct inode *inode);
3663 
3664 
3665 /* move_extent.c */
3666 extern void ext4_double_down_write_data_sem(struct inode *first,
3667 					    struct inode *second);
3668 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3669 					  struct inode *donor_inode);
3670 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3671 			     __u64 start_orig, __u64 start_donor,
3672 			     __u64 len, __u64 *moved_len);
3673 
3674 /* page-io.c */
3675 extern int __init ext4_init_pageio(void);
3676 extern void ext4_exit_pageio(void);
3677 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3678 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3679 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3680 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3681 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3682 				struct writeback_control *wbc);
3683 extern void ext4_end_io_rsv_work(struct work_struct *work);
3684 extern void ext4_io_submit(struct ext4_io_submit *io);
3685 int ext4_bio_write_folio(struct ext4_io_submit *io, struct folio *page,
3686 		size_t len);
3687 extern struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end);
3688 extern struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end);
3689 
3690 /* mmp.c */
3691 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3692 
3693 /* mmp.c */
3694 extern void ext4_stop_mmpd(struct ext4_sb_info *sbi);
3695 
3696 /* verity.c */
3697 extern const struct fsverity_operations ext4_verityops;
3698 
3699 /* orphan.c */
3700 extern int ext4_orphan_add(handle_t *, struct inode *);
3701 extern int ext4_orphan_del(handle_t *, struct inode *);
3702 extern void ext4_orphan_cleanup(struct super_block *sb,
3703 				struct ext4_super_block *es);
3704 extern void ext4_release_orphan_info(struct super_block *sb);
3705 extern int ext4_init_orphan_info(struct super_block *sb);
3706 extern int ext4_orphan_file_empty(struct super_block *sb);
3707 extern void ext4_orphan_file_block_trigger(
3708 				struct jbd2_buffer_trigger_type *triggers,
3709 				struct buffer_head *bh,
3710 				void *data, size_t size);
3711 
3712 /*
3713  * Add new method to test whether block and inode bitmaps are properly
3714  * initialized. With uninit_bg reading the block from disk is not enough
3715  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3716  */
3717 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3718 
3719 static inline int bitmap_uptodate(struct buffer_head *bh)
3720 {
3721 	return (buffer_uptodate(bh) &&
3722 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3723 }
3724 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3725 {
3726 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3727 }
3728 
3729 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3730 
3731 /* For ioend & aio unwritten conversion wait queues */
3732 #define EXT4_WQ_HASH_SZ		37
3733 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3734 					    EXT4_WQ_HASH_SZ])
3735 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3736 
3737 extern int ext4_resize_begin(struct super_block *sb);
3738 extern int ext4_resize_end(struct super_block *sb, bool update_backups);
3739 
3740 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3741 					      struct ext4_io_end *io_end)
3742 {
3743 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3744 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3745 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3746 	}
3747 }
3748 
3749 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3750 {
3751 	struct inode *inode = io_end->inode;
3752 
3753 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3754 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3755 		/* Wake up anyone waiting on unwritten extent conversion */
3756 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3757 			wake_up_all(ext4_ioend_wq(inode));
3758 	}
3759 }
3760 
3761 extern const struct iomap_ops ext4_iomap_ops;
3762 extern const struct iomap_ops ext4_iomap_overwrite_ops;
3763 extern const struct iomap_ops ext4_iomap_report_ops;
3764 
3765 static inline int ext4_buffer_uptodate(struct buffer_head *bh)
3766 {
3767 	/*
3768 	 * If the buffer has the write error flag, we have failed
3769 	 * to write out data in the block.  In this  case, we don't
3770 	 * have to read the block because we may read the old data
3771 	 * successfully.
3772 	 */
3773 	if (buffer_write_io_error(bh))
3774 		set_buffer_uptodate(bh);
3775 	return buffer_uptodate(bh);
3776 }
3777 
3778 #endif	/* __KERNEL__ */
3779 
3780 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3781 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3782 
3783 #endif	/* _EXT4_H */
3784