xref: /openbmc/linux/fs/ext4/ext4.h (revision c5c87812)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  ext4.h
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/include/linux/minix_fs.h
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  */
16 
17 #ifndef _EXT4_H
18 #define _EXT4_H
19 
20 #include <linux/types.h>
21 #include <linux/blkdev.h>
22 #include <linux/magic.h>
23 #include <linux/jbd2.h>
24 #include <linux/quota.h>
25 #include <linux/rwsem.h>
26 #include <linux/rbtree.h>
27 #include <linux/seqlock.h>
28 #include <linux/mutex.h>
29 #include <linux/timer.h>
30 #include <linux/wait.h>
31 #include <linux/sched/signal.h>
32 #include <linux/blockgroup_lock.h>
33 #include <linux/percpu_counter.h>
34 #include <linux/ratelimit.h>
35 #include <crypto/hash.h>
36 #include <linux/falloc.h>
37 #include <linux/percpu-rwsem.h>
38 #include <linux/fiemap.h>
39 #ifdef __KERNEL__
40 #include <linux/compat.h>
41 #endif
42 
43 #include <linux/fscrypt.h>
44 #include <linux/fsverity.h>
45 
46 #include <linux/compiler.h>
47 
48 /*
49  * The fourth extended filesystem constants/structures
50  */
51 
52 /*
53  * with AGGRESSIVE_CHECK allocator runs consistency checks over
54  * structures. these checks slow things down a lot
55  */
56 #define AGGRESSIVE_CHECK__
57 
58 /*
59  * with DOUBLE_CHECK defined mballoc creates persistent in-core
60  * bitmaps, maintains and uses them to check for double allocations
61  */
62 #define DOUBLE_CHECK__
63 
64 /*
65  * Define EXT4FS_DEBUG to produce debug messages
66  */
67 #undef EXT4FS_DEBUG
68 
69 /*
70  * Debug code
71  */
72 #ifdef EXT4FS_DEBUG
73 #define ext4_debug(f, a...)						\
74 	do {								\
75 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
76 			__FILE__, __LINE__, __func__);			\
77 		printk(KERN_DEBUG f, ## a);				\
78 	} while (0)
79 #else
80 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
81 #endif
82 
83  /*
84   * Turn on EXT_DEBUG to enable ext4_ext_show_path/leaf/move in extents.c
85   */
86 #define EXT_DEBUG__
87 
88 /*
89  * Dynamic printk for controlled extents debugging.
90  */
91 #ifdef CONFIG_EXT4_DEBUG
92 #define ext_debug(ino, fmt, ...)					\
93 	pr_debug("[%s/%d] EXT4-fs (%s): ino %lu: (%s, %d): %s:" fmt,	\
94 		 current->comm, task_pid_nr(current),			\
95 		 ino->i_sb->s_id, ino->i_ino, __FILE__, __LINE__,	\
96 		 __func__, ##__VA_ARGS__)
97 #else
98 #define ext_debug(ino, fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
99 #endif
100 
101 /* data type for block offset of block group */
102 typedef int ext4_grpblk_t;
103 
104 /* data type for filesystem-wide blocks number */
105 typedef unsigned long long ext4_fsblk_t;
106 
107 /* data type for file logical block number */
108 typedef __u32 ext4_lblk_t;
109 
110 /* data type for block group number */
111 typedef unsigned int ext4_group_t;
112 
113 enum SHIFT_DIRECTION {
114 	SHIFT_LEFT = 0,
115 	SHIFT_RIGHT,
116 };
117 
118 /*
119  * Flags used in mballoc's allocation_context flags field.
120  *
121  * Also used to show what's going on for debugging purposes when the
122  * flag field is exported via the traceport interface
123  */
124 
125 /* prefer goal again. length */
126 #define EXT4_MB_HINT_MERGE		0x0001
127 /* blocks already reserved */
128 #define EXT4_MB_HINT_RESERVED		0x0002
129 /* metadata is being allocated */
130 #define EXT4_MB_HINT_METADATA		0x0004
131 /* first blocks in the file */
132 #define EXT4_MB_HINT_FIRST		0x0008
133 /* search for the best chunk */
134 #define EXT4_MB_HINT_BEST		0x0010
135 /* data is being allocated */
136 #define EXT4_MB_HINT_DATA		0x0020
137 /* don't preallocate (for tails) */
138 #define EXT4_MB_HINT_NOPREALLOC		0x0040
139 /* allocate for locality group */
140 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
141 /* allocate goal blocks or none */
142 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
143 /* goal is meaningful */
144 #define EXT4_MB_HINT_TRY_GOAL		0x0200
145 /* blocks already pre-reserved by delayed allocation */
146 #define EXT4_MB_DELALLOC_RESERVED	0x0400
147 /* We are doing stream allocation */
148 #define EXT4_MB_STREAM_ALLOC		0x0800
149 /* Use reserved root blocks if needed */
150 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
151 /* Use blocks from reserved pool */
152 #define EXT4_MB_USE_RESERVED		0x2000
153 /* Do strict check for free blocks while retrying block allocation */
154 #define EXT4_MB_STRICT_CHECK		0x4000
155 
156 struct ext4_allocation_request {
157 	/* target inode for block we're allocating */
158 	struct inode *inode;
159 	/* how many blocks we want to allocate */
160 	unsigned int len;
161 	/* logical block in target inode */
162 	ext4_lblk_t logical;
163 	/* the closest logical allocated block to the left */
164 	ext4_lblk_t lleft;
165 	/* the closest logical allocated block to the right */
166 	ext4_lblk_t lright;
167 	/* phys. target (a hint) */
168 	ext4_fsblk_t goal;
169 	/* phys. block for the closest logical allocated block to the left */
170 	ext4_fsblk_t pleft;
171 	/* phys. block for the closest logical allocated block to the right */
172 	ext4_fsblk_t pright;
173 	/* flags. see above EXT4_MB_HINT_* */
174 	unsigned int flags;
175 };
176 
177 /*
178  * Logical to physical block mapping, used by ext4_map_blocks()
179  *
180  * This structure is used to pass requests into ext4_map_blocks() as
181  * well as to store the information returned by ext4_map_blocks().  It
182  * takes less room on the stack than a struct buffer_head.
183  */
184 #define EXT4_MAP_NEW		BIT(BH_New)
185 #define EXT4_MAP_MAPPED		BIT(BH_Mapped)
186 #define EXT4_MAP_UNWRITTEN	BIT(BH_Unwritten)
187 #define EXT4_MAP_BOUNDARY	BIT(BH_Boundary)
188 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
189 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
190 
191 struct ext4_map_blocks {
192 	ext4_fsblk_t m_pblk;
193 	ext4_lblk_t m_lblk;
194 	unsigned int m_len;
195 	unsigned int m_flags;
196 };
197 
198 /*
199  * Block validity checking, system zone rbtree.
200  */
201 struct ext4_system_blocks {
202 	struct rb_root root;
203 	struct rcu_head rcu;
204 };
205 
206 /*
207  * Flags for ext4_io_end->flags
208  */
209 #define	EXT4_IO_END_UNWRITTEN	0x0001
210 
211 struct ext4_io_end_vec {
212 	struct list_head list;		/* list of io_end_vec */
213 	loff_t offset;			/* offset in the file */
214 	ssize_t size;			/* size of the extent */
215 };
216 
217 /*
218  * For converting unwritten extents on a work queue. 'handle' is used for
219  * buffered writeback.
220  */
221 typedef struct ext4_io_end {
222 	struct list_head	list;		/* per-file finished IO list */
223 	handle_t		*handle;	/* handle reserved for extent
224 						 * conversion */
225 	struct inode		*inode;		/* file being written to */
226 	struct bio		*bio;		/* Linked list of completed
227 						 * bios covering the extent */
228 	unsigned int		flag;		/* unwritten or not */
229 	atomic_t		count;		/* reference counter */
230 	struct list_head	list_vec;	/* list of ext4_io_end_vec */
231 } ext4_io_end_t;
232 
233 struct ext4_io_submit {
234 	struct writeback_control *io_wbc;
235 	struct bio		*io_bio;
236 	ext4_io_end_t		*io_end;
237 	sector_t		io_next_block;
238 };
239 
240 /*
241  * Special inodes numbers
242  */
243 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
244 #define EXT4_ROOT_INO		 2	/* Root inode */
245 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
246 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
247 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
248 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
249 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
250 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
251 
252 /* First non-reserved inode for old ext4 filesystems */
253 #define EXT4_GOOD_OLD_FIRST_INO	11
254 
255 /*
256  * Maximal count of links to a file
257  */
258 #define EXT4_LINK_MAX		65000
259 
260 /*
261  * Macro-instructions used to manage several block sizes
262  */
263 #define EXT4_MIN_BLOCK_SIZE		1024
264 #define	EXT4_MAX_BLOCK_SIZE		65536
265 #define EXT4_MIN_BLOCK_LOG_SIZE		10
266 #define EXT4_MAX_BLOCK_LOG_SIZE		16
267 #define EXT4_MAX_CLUSTER_LOG_SIZE	30
268 #ifdef __KERNEL__
269 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
270 #else
271 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
272 #endif
273 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
274 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
275 					 EXT4_SB(s)->s_cluster_bits)
276 #ifdef __KERNEL__
277 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
278 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
279 #else
280 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
281 #endif
282 #ifdef __KERNEL__
283 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
284 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
285 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
286 #else
287 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
288 				 EXT4_GOOD_OLD_INODE_SIZE : \
289 				 (s)->s_inode_size)
290 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
291 				 EXT4_GOOD_OLD_FIRST_INO : \
292 				 (s)->s_first_ino)
293 #endif
294 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
295 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
296 	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
297 								  blkbits))
298 
299 /* Translate a block number to a cluster number */
300 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
301 /* Translate a cluster number to a block number */
302 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
303 /* Translate # of blks to # of clusters */
304 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
305 				 (sbi)->s_cluster_bits)
306 /* Mask out the low bits to get the starting block of the cluster */
307 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
308 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
309 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
310 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
311 /* Fill in the low bits to get the last block of the cluster */
312 #define EXT4_LBLK_CFILL(sbi, lblk) ((lblk) |				\
313 				    ((ext4_lblk_t) (sbi)->s_cluster_ratio - 1))
314 /* Get the cluster offset */
315 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
316 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
317 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
318 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
319 
320 /*
321  * Structure of a blocks group descriptor
322  */
323 struct ext4_group_desc
324 {
325 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
326 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
327 	__le32	bg_inode_table_lo;	/* Inodes table block */
328 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
329 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
330 	__le16	bg_used_dirs_count_lo;	/* Directories count */
331 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
332 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
333 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
334 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
335 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
336 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
337 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
338 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
339 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
340 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
341 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
342 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
343 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
344 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
345 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
346 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
347 	__u32   bg_reserved;
348 };
349 
350 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
351 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
352 	 sizeof(__le16))
353 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
354 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
355 	 sizeof(__le16))
356 
357 /*
358  * Structure of a flex block group info
359  */
360 
361 struct flex_groups {
362 	atomic64_t	free_clusters;
363 	atomic_t	free_inodes;
364 	atomic_t	used_dirs;
365 };
366 
367 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
368 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
369 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
370 
371 /*
372  * Macro-instructions used to manage group descriptors
373  */
374 #define EXT4_MIN_DESC_SIZE		32
375 #define EXT4_MIN_DESC_SIZE_64BIT	64
376 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
377 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
378 #ifdef __KERNEL__
379 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
380 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
381 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
382 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
383 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
384 #else
385 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
386 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
387 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
388 #endif
389 
390 /*
391  * Constants relative to the data blocks
392  */
393 #define	EXT4_NDIR_BLOCKS		12
394 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
395 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
396 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
397 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
398 
399 /*
400  * Inode flags
401  */
402 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
403 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
404 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
405 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
406 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
407 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
408 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
409 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
410 /* Reserved for compression usage... */
411 #define EXT4_DIRTY_FL			0x00000100
412 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
413 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
414 	/* nb: was previously EXT2_ECOMPR_FL */
415 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
416 /* End compression flags --- maybe not all used */
417 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
418 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
419 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
420 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
421 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
422 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
423 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
424 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
425 #define EXT4_VERITY_FL			0x00100000 /* Verity protected inode */
426 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
427 /* 0x00400000 was formerly EXT4_EOFBLOCKS_FL */
428 
429 #define EXT4_DAX_FL			0x02000000 /* Inode is DAX */
430 
431 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
432 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
433 #define EXT4_CASEFOLD_FL		0x40000000 /* Casefolded directory */
434 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
435 
436 /* User modifiable flags */
437 #define EXT4_FL_USER_MODIFIABLE		(EXT4_SECRM_FL | \
438 					 EXT4_UNRM_FL | \
439 					 EXT4_COMPR_FL | \
440 					 EXT4_SYNC_FL | \
441 					 EXT4_IMMUTABLE_FL | \
442 					 EXT4_APPEND_FL | \
443 					 EXT4_NODUMP_FL | \
444 					 EXT4_NOATIME_FL | \
445 					 EXT4_JOURNAL_DATA_FL | \
446 					 EXT4_NOTAIL_FL | \
447 					 EXT4_DIRSYNC_FL | \
448 					 EXT4_TOPDIR_FL | \
449 					 EXT4_EXTENTS_FL | \
450 					 0x00400000 /* EXT4_EOFBLOCKS_FL */ | \
451 					 EXT4_DAX_FL | \
452 					 EXT4_PROJINHERIT_FL | \
453 					 EXT4_CASEFOLD_FL)
454 
455 /* User visible flags */
456 #define EXT4_FL_USER_VISIBLE		(EXT4_FL_USER_MODIFIABLE | \
457 					 EXT4_DIRTY_FL | \
458 					 EXT4_COMPRBLK_FL | \
459 					 EXT4_NOCOMPR_FL | \
460 					 EXT4_ENCRYPT_FL | \
461 					 EXT4_INDEX_FL | \
462 					 EXT4_VERITY_FL | \
463 					 EXT4_INLINE_DATA_FL)
464 
465 /* Flags we can manipulate with through FS_IOC_FSSETXATTR */
466 #define EXT4_FL_XFLAG_VISIBLE		(EXT4_SYNC_FL | \
467 					 EXT4_IMMUTABLE_FL | \
468 					 EXT4_APPEND_FL | \
469 					 EXT4_NODUMP_FL | \
470 					 EXT4_NOATIME_FL | \
471 					 EXT4_PROJINHERIT_FL | \
472 					 EXT4_DAX_FL)
473 
474 /* Flags that should be inherited by new inodes from their parent. */
475 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
476 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
477 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
478 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
479 			   EXT4_PROJINHERIT_FL | EXT4_CASEFOLD_FL |\
480 			   EXT4_DAX_FL)
481 
482 /* Flags that are appropriate for regular files (all but dir-specific ones). */
483 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL | EXT4_CASEFOLD_FL |\
484 			   EXT4_PROJINHERIT_FL))
485 
486 /* Flags that are appropriate for non-directories/regular files. */
487 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
488 
489 /* The only flags that should be swapped */
490 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
491 
492 /* Flags which are mutually exclusive to DAX */
493 #define EXT4_DAX_MUT_EXCL (EXT4_VERITY_FL | EXT4_ENCRYPT_FL |\
494 			   EXT4_JOURNAL_DATA_FL | EXT4_INLINE_DATA_FL)
495 
496 /* Mask out flags that are inappropriate for the given type of inode. */
497 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
498 {
499 	if (S_ISDIR(mode))
500 		return flags;
501 	else if (S_ISREG(mode))
502 		return flags & EXT4_REG_FLMASK;
503 	else
504 		return flags & EXT4_OTHER_FLMASK;
505 }
506 
507 /*
508  * Inode flags used for atomic set/get
509  */
510 enum {
511 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
512 	EXT4_INODE_UNRM		= 1,	/* Undelete */
513 	EXT4_INODE_COMPR	= 2,	/* Compress file */
514 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
515 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
516 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
517 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
518 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
519 /* Reserved for compression usage... */
520 	EXT4_INODE_DIRTY	= 8,
521 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
522 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
523 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
524 /* End compression flags --- maybe not all used */
525 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
526 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
527 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
528 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
529 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
530 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
531 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
532 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
533 	EXT4_INODE_VERITY	= 20,	/* Verity protected inode */
534 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
535 /* 22 was formerly EXT4_INODE_EOFBLOCKS */
536 	EXT4_INODE_DAX		= 25,	/* Inode is DAX */
537 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
538 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
539 	EXT4_INODE_CASEFOLD	= 30,	/* Casefolded directory */
540 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
541 };
542 
543 /*
544  * Since it's pretty easy to mix up bit numbers and hex values, we use a
545  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
546  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
547  * any extra space in the compiled kernel image, otherwise, the build will fail.
548  * It's important that these values are the same, since we are using
549  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
550  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
551  * values found in ext2, ext3 and ext4 filesystems, and of course the values
552  * defined in e2fsprogs.
553  *
554  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
555  */
556 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
557 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
558 
559 static inline void ext4_check_flag_values(void)
560 {
561 	CHECK_FLAG_VALUE(SECRM);
562 	CHECK_FLAG_VALUE(UNRM);
563 	CHECK_FLAG_VALUE(COMPR);
564 	CHECK_FLAG_VALUE(SYNC);
565 	CHECK_FLAG_VALUE(IMMUTABLE);
566 	CHECK_FLAG_VALUE(APPEND);
567 	CHECK_FLAG_VALUE(NODUMP);
568 	CHECK_FLAG_VALUE(NOATIME);
569 	CHECK_FLAG_VALUE(DIRTY);
570 	CHECK_FLAG_VALUE(COMPRBLK);
571 	CHECK_FLAG_VALUE(NOCOMPR);
572 	CHECK_FLAG_VALUE(ENCRYPT);
573 	CHECK_FLAG_VALUE(INDEX);
574 	CHECK_FLAG_VALUE(IMAGIC);
575 	CHECK_FLAG_VALUE(JOURNAL_DATA);
576 	CHECK_FLAG_VALUE(NOTAIL);
577 	CHECK_FLAG_VALUE(DIRSYNC);
578 	CHECK_FLAG_VALUE(TOPDIR);
579 	CHECK_FLAG_VALUE(HUGE_FILE);
580 	CHECK_FLAG_VALUE(EXTENTS);
581 	CHECK_FLAG_VALUE(VERITY);
582 	CHECK_FLAG_VALUE(EA_INODE);
583 	CHECK_FLAG_VALUE(INLINE_DATA);
584 	CHECK_FLAG_VALUE(PROJINHERIT);
585 	CHECK_FLAG_VALUE(CASEFOLD);
586 	CHECK_FLAG_VALUE(RESERVED);
587 }
588 
589 /* Used to pass group descriptor data when online resize is done */
590 struct ext4_new_group_input {
591 	__u32 group;		/* Group number for this data */
592 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
593 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
594 	__u64 inode_table;	/* Absolute block number of inode table start */
595 	__u32 blocks_count;	/* Total number of blocks in this group */
596 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
597 	__u16 unused;
598 };
599 
600 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
601 struct compat_ext4_new_group_input {
602 	u32 group;
603 	compat_u64 block_bitmap;
604 	compat_u64 inode_bitmap;
605 	compat_u64 inode_table;
606 	u32 blocks_count;
607 	u16 reserved_blocks;
608 	u16 unused;
609 };
610 #endif
611 
612 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
613 struct ext4_new_group_data {
614 	__u32 group;
615 	__u64 block_bitmap;
616 	__u64 inode_bitmap;
617 	__u64 inode_table;
618 	__u32 blocks_count;
619 	__u16 reserved_blocks;
620 	__u16 mdata_blocks;
621 	__u32 free_clusters_count;
622 };
623 
624 /* Indexes used to index group tables in ext4_new_group_data */
625 enum {
626 	BLOCK_BITMAP = 0,	/* block bitmap */
627 	INODE_BITMAP,		/* inode bitmap */
628 	INODE_TABLE,		/* inode tables */
629 	GROUP_TABLE_COUNT,
630 };
631 
632 /*
633  * Flags used by ext4_map_blocks()
634  */
635 	/* Allocate any needed blocks and/or convert an unwritten
636 	   extent to be an initialized ext4 */
637 #define EXT4_GET_BLOCKS_CREATE			0x0001
638 	/* Request the creation of an unwritten extent */
639 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
640 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
641 						 EXT4_GET_BLOCKS_CREATE)
642 	/* Caller is from the delayed allocation writeout path
643 	 * finally doing the actual allocation of delayed blocks */
644 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
645 	/* caller is from the direct IO path, request to creation of an
646 	unwritten extents if not allocated, split the unwritten
647 	extent if blocks has been preallocated already*/
648 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
649 #define EXT4_GET_BLOCKS_CONVERT			0x0010
650 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
651 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
652 	/* Convert extent to initialized after IO complete */
653 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
654 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
655 	/* Eventual metadata allocation (due to growing extent tree)
656 	 * should not fail, so try to use reserved blocks for that.*/
657 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
658 	/* Don't normalize allocation size (used for fallocate) */
659 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
660 	/* Convert written extents to unwritten */
661 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
662 	/* Write zeros to newly created written extents */
663 #define EXT4_GET_BLOCKS_ZERO			0x0200
664 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
665 					EXT4_GET_BLOCKS_ZERO)
666 	/* Caller will submit data before dropping transaction handle. This
667 	 * allows jbd2 to avoid submitting data before commit. */
668 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
669 
670 /*
671  * The bit position of these flags must not overlap with any of the
672  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
673  * read_extent_tree_block(), ext4_split_extent_at(),
674  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
675  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
676  * caching the extents when reading from the extent tree while a
677  * truncate or punch hole operation is in progress.
678  */
679 #define EXT4_EX_NOCACHE				0x40000000
680 #define EXT4_EX_FORCE_CACHE			0x20000000
681 #define EXT4_EX_NOFAIL				0x10000000
682 
683 /*
684  * Flags used by ext4_free_blocks
685  */
686 #define EXT4_FREE_BLOCKS_METADATA		0x0001
687 #define EXT4_FREE_BLOCKS_FORGET			0x0002
688 #define EXT4_FREE_BLOCKS_VALIDATED		0x0004
689 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE		0x0008
690 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
691 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
692 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
693 
694 /*
695  * ioctl commands
696  */
697 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
698 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
699 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
700 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
701 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
702 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
703 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
704 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
705 #define EXT4_IOC_MIGRATE		_IO('f', 9)
706  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
707  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
708 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
709 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
710 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
711 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
712 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
713 /* ioctl codes 19--39 are reserved for fscrypt */
714 #define EXT4_IOC_CLEAR_ES_CACHE		_IO('f', 40)
715 #define EXT4_IOC_GETSTATE		_IOW('f', 41, __u32)
716 #define EXT4_IOC_GET_ES_CACHE		_IOWR('f', 42, struct fiemap)
717 
718 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
719 
720 /*
721  * Flags for going down operation
722  */
723 #define EXT4_GOING_FLAGS_DEFAULT		0x0	/* going down */
724 #define EXT4_GOING_FLAGS_LOGFLUSH		0x1	/* flush log but not data */
725 #define EXT4_GOING_FLAGS_NOLOGFLUSH		0x2	/* don't flush log nor data */
726 
727 /*
728  * Flags returned by EXT4_IOC_GETSTATE
729  *
730  * We only expose to userspace a subset of the state flags in
731  * i_state_flags
732  */
733 #define EXT4_STATE_FLAG_EXT_PRECACHED	0x00000001
734 #define EXT4_STATE_FLAG_NEW		0x00000002
735 #define EXT4_STATE_FLAG_NEWENTRY	0x00000004
736 #define EXT4_STATE_FLAG_DA_ALLOC_CLOSE	0x00000008
737 
738 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
739 /*
740  * ioctl commands in 32 bit emulation
741  */
742 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
743 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
744 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
745 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
746 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
747 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
748 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
749 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
750 #endif
751 
752 /*
753  * Returned by EXT4_IOC_GET_ES_CACHE as an additional possible flag.
754  * It indicates that the entry in extent status cache is for a hole.
755  */
756 #define EXT4_FIEMAP_EXTENT_HOLE		0x08000000
757 
758 /* Max physical block we can address w/o extents */
759 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
760 
761 /* Max logical block we can support */
762 #define EXT4_MAX_LOGICAL_BLOCK		0xFFFFFFFE
763 
764 /*
765  * Structure of an inode on the disk
766  */
767 struct ext4_inode {
768 	__le16	i_mode;		/* File mode */
769 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
770 	__le32	i_size_lo;	/* Size in bytes */
771 	__le32	i_atime;	/* Access time */
772 	__le32	i_ctime;	/* Inode Change time */
773 	__le32	i_mtime;	/* Modification time */
774 	__le32	i_dtime;	/* Deletion Time */
775 	__le16	i_gid;		/* Low 16 bits of Group Id */
776 	__le16	i_links_count;	/* Links count */
777 	__le32	i_blocks_lo;	/* Blocks count */
778 	__le32	i_flags;	/* File flags */
779 	union {
780 		struct {
781 			__le32  l_i_version;
782 		} linux1;
783 		struct {
784 			__u32  h_i_translator;
785 		} hurd1;
786 		struct {
787 			__u32  m_i_reserved1;
788 		} masix1;
789 	} osd1;				/* OS dependent 1 */
790 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
791 	__le32	i_generation;	/* File version (for NFS) */
792 	__le32	i_file_acl_lo;	/* File ACL */
793 	__le32	i_size_high;
794 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
795 	union {
796 		struct {
797 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
798 			__le16	l_i_file_acl_high;
799 			__le16	l_i_uid_high;	/* these 2 fields */
800 			__le16	l_i_gid_high;	/* were reserved2[0] */
801 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
802 			__le16	l_i_reserved;
803 		} linux2;
804 		struct {
805 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
806 			__u16	h_i_mode_high;
807 			__u16	h_i_uid_high;
808 			__u16	h_i_gid_high;
809 			__u32	h_i_author;
810 		} hurd2;
811 		struct {
812 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
813 			__le16	m_i_file_acl_high;
814 			__u32	m_i_reserved2[2];
815 		} masix2;
816 	} osd2;				/* OS dependent 2 */
817 	__le16	i_extra_isize;
818 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
819 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
820 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
821 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
822 	__le32  i_crtime;       /* File Creation time */
823 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
824 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
825 	__le32	i_projid;	/* Project ID */
826 };
827 
828 struct move_extent {
829 	__u32 reserved;		/* should be zero */
830 	__u32 donor_fd;		/* donor file descriptor */
831 	__u64 orig_start;	/* logical start offset in block for orig */
832 	__u64 donor_start;	/* logical start offset in block for donor */
833 	__u64 len;		/* block length to be moved */
834 	__u64 moved_len;	/* moved block length */
835 };
836 
837 #define EXT4_EPOCH_BITS 2
838 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
839 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
840 
841 /*
842  * Extended fields will fit into an inode if the filesystem was formatted
843  * with large inodes (-I 256 or larger) and there are not currently any EAs
844  * consuming all of the available space. For new inodes we always reserve
845  * enough space for the kernel's known extended fields, but for inodes
846  * created with an old kernel this might not have been the case. None of
847  * the extended inode fields is critical for correct filesystem operation.
848  * This macro checks if a certain field fits in the inode. Note that
849  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
850  */
851 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
852 	((offsetof(typeof(*ext4_inode), field) +	\
853 	  sizeof((ext4_inode)->field))			\
854 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
855 	    (einode)->i_extra_isize))			\
856 
857 /*
858  * We use an encoding that preserves the times for extra epoch "00":
859  *
860  * extra  msb of                         adjust for signed
861  * epoch  32-bit                         32-bit tv_sec to
862  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
863  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
864  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
865  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
866  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
867  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
868  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
869  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
870  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
871  *
872  * Note that previous versions of the kernel on 64-bit systems would
873  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
874  * 1970.  e2fsck will correct this, assuming that it is run on the
875  * affected filesystem before 2242.
876  */
877 
878 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
879 {
880 	u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
881 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
882 }
883 
884 static inline void ext4_decode_extra_time(struct timespec64 *time,
885 					  __le32 extra)
886 {
887 	if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK)))
888 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
889 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
890 }
891 
892 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)				\
893 do {										\
894 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
895 		(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	\
896 		(raw_inode)->xtime ## _extra =					\
897 				ext4_encode_extra_time(&(inode)->xtime);	\
898 		}								\
899 	else	\
900 		(raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (inode)->xtime.tv_sec, S32_MIN, S32_MAX));	\
901 } while (0)
902 
903 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
904 do {									       \
905 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
906 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
907 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
908 		(raw_inode)->xtime ## _extra =				       \
909 				ext4_encode_extra_time(&(einode)->xtime);      \
910 } while (0)
911 
912 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)				\
913 do {										\
914 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);	\
915 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {	\
916 		ext4_decode_extra_time(&(inode)->xtime,				\
917 				       raw_inode->xtime ## _extra);		\
918 		}								\
919 	else									\
920 		(inode)->xtime.tv_nsec = 0;					\
921 } while (0)
922 
923 
924 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
925 do {									       \
926 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
927 		(einode)->xtime.tv_sec = 				       \
928 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
929 	else								       \
930 		(einode)->xtime.tv_sec = 0;				       \
931 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
932 		ext4_decode_extra_time(&(einode)->xtime,		       \
933 				       raw_inode->xtime ## _extra);	       \
934 	else								       \
935 		(einode)->xtime.tv_nsec = 0;				       \
936 } while (0)
937 
938 #define i_disk_version osd1.linux1.l_i_version
939 
940 #if defined(__KERNEL__) || defined(__linux__)
941 #define i_reserved1	osd1.linux1.l_i_reserved1
942 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
943 #define i_blocks_high	osd2.linux2.l_i_blocks_high
944 #define i_uid_low	i_uid
945 #define i_gid_low	i_gid
946 #define i_uid_high	osd2.linux2.l_i_uid_high
947 #define i_gid_high	osd2.linux2.l_i_gid_high
948 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
949 
950 #elif defined(__GNU__)
951 
952 #define i_translator	osd1.hurd1.h_i_translator
953 #define i_uid_high	osd2.hurd2.h_i_uid_high
954 #define i_gid_high	osd2.hurd2.h_i_gid_high
955 #define i_author	osd2.hurd2.h_i_author
956 
957 #elif defined(__masix__)
958 
959 #define i_reserved1	osd1.masix1.m_i_reserved1
960 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
961 #define i_reserved2	osd2.masix2.m_i_reserved2
962 
963 #endif /* defined(__KERNEL__) || defined(__linux__) */
964 
965 #include "extents_status.h"
966 #include "fast_commit.h"
967 
968 /*
969  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
970  *
971  * These are needed to avoid lockdep false positives when we need to
972  * allocate blocks to the quota inode during ext4_map_blocks(), while
973  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
974  * do quota tracking for the quota inode, this avoids deadlock (as
975  * well as infinite recursion, since it isn't turtles all the way
976  * down...)
977  *
978  *  I_DATA_SEM_NORMAL - Used for most inodes
979  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
980  *			  where the second inode has larger inode number
981  *			  than the first
982  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
983  */
984 enum {
985 	I_DATA_SEM_NORMAL = 0,
986 	I_DATA_SEM_OTHER,
987 	I_DATA_SEM_QUOTA,
988 };
989 
990 
991 /*
992  * fourth extended file system inode data in memory
993  */
994 struct ext4_inode_info {
995 	__le32	i_data[15];	/* unconverted */
996 	__u32	i_dtime;
997 	ext4_fsblk_t	i_file_acl;
998 
999 	/*
1000 	 * i_block_group is the number of the block group which contains
1001 	 * this file's inode.  Constant across the lifetime of the inode,
1002 	 * it is used for making block allocation decisions - we try to
1003 	 * place a file's data blocks near its inode block, and new inodes
1004 	 * near to their parent directory's inode.
1005 	 */
1006 	ext4_group_t	i_block_group;
1007 	ext4_lblk_t	i_dir_start_lookup;
1008 #if (BITS_PER_LONG < 64)
1009 	unsigned long	i_state_flags;		/* Dynamic state flags */
1010 #endif
1011 	unsigned long	i_flags;
1012 
1013 	/*
1014 	 * Extended attributes can be read independently of the main file
1015 	 * data. Taking i_mutex even when reading would cause contention
1016 	 * between readers of EAs and writers of regular file data, so
1017 	 * instead we synchronize on xattr_sem when reading or changing
1018 	 * EAs.
1019 	 */
1020 	struct rw_semaphore xattr_sem;
1021 
1022 	struct list_head i_orphan;	/* unlinked but open inodes */
1023 
1024 	/* Fast commit related info */
1025 
1026 	struct list_head i_fc_list;	/*
1027 					 * inodes that need fast commit
1028 					 * protected by sbi->s_fc_lock.
1029 					 */
1030 
1031 	/* Fast commit subtid when this inode was committed */
1032 	unsigned int i_fc_committed_subtid;
1033 
1034 	/* Start of lblk range that needs to be committed in this fast commit */
1035 	ext4_lblk_t i_fc_lblk_start;
1036 
1037 	/* End of lblk range that needs to be committed in this fast commit */
1038 	ext4_lblk_t i_fc_lblk_len;
1039 
1040 	/* Number of ongoing updates on this inode */
1041 	atomic_t  i_fc_updates;
1042 
1043 	/* Fast commit wait queue for this inode */
1044 	wait_queue_head_t i_fc_wait;
1045 
1046 	/* Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len */
1047 	struct mutex i_fc_lock;
1048 
1049 	/*
1050 	 * i_disksize keeps track of what the inode size is ON DISK, not
1051 	 * in memory.  During truncate, i_size is set to the new size by
1052 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
1053 	 * set i_disksize to 0 until the truncate is actually under way.
1054 	 *
1055 	 * The intent is that i_disksize always represents the blocks which
1056 	 * are used by this file.  This allows recovery to restart truncate
1057 	 * on orphans if we crash during truncate.  We actually write i_disksize
1058 	 * into the on-disk inode when writing inodes out, instead of i_size.
1059 	 *
1060 	 * The only time when i_disksize and i_size may be different is when
1061 	 * a truncate is in progress.  The only things which change i_disksize
1062 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
1063 	 */
1064 	loff_t	i_disksize;
1065 
1066 	/*
1067 	 * i_data_sem is for serialising ext4_truncate() against
1068 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
1069 	 * data tree are chopped off during truncate. We can't do that in
1070 	 * ext4 because whenever we perform intermediate commits during
1071 	 * truncate, the inode and all the metadata blocks *must* be in a
1072 	 * consistent state which allows truncation of the orphans to restart
1073 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
1074 	 * by other means, so we have i_data_sem.
1075 	 */
1076 	struct rw_semaphore i_data_sem;
1077 	/*
1078 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
1079 	 * operations. We have to make sure that new page cannot be faulted in
1080 	 * a section of the inode that is being punched. We cannot easily use
1081 	 * i_data_sem for this since we need protection for the whole punch
1082 	 * operation and i_data_sem ranks below transaction start so we have
1083 	 * to occasionally drop it.
1084 	 */
1085 	struct rw_semaphore i_mmap_sem;
1086 	struct inode vfs_inode;
1087 	struct jbd2_inode *jinode;
1088 
1089 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
1090 
1091 	/*
1092 	 * File creation time. Its function is same as that of
1093 	 * struct timespec64 i_{a,c,m}time in the generic inode.
1094 	 */
1095 	struct timespec64 i_crtime;
1096 
1097 	/* mballoc */
1098 	atomic_t i_prealloc_active;
1099 	struct list_head i_prealloc_list;
1100 	spinlock_t i_prealloc_lock;
1101 
1102 	/* extents status tree */
1103 	struct ext4_es_tree i_es_tree;
1104 	rwlock_t i_es_lock;
1105 	struct list_head i_es_list;
1106 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1107 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1108 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1109 					   extents to shrink. Protected by
1110 					   i_es_lock  */
1111 
1112 	/* ialloc */
1113 	ext4_group_t	i_last_alloc_group;
1114 
1115 	/* allocation reservation info for delalloc */
1116 	/* In case of bigalloc, this refer to clusters rather than blocks */
1117 	unsigned int i_reserved_data_blocks;
1118 
1119 	/* pending cluster reservations for bigalloc file systems */
1120 	struct ext4_pending_tree i_pending_tree;
1121 
1122 	/* on-disk additional length */
1123 	__u16 i_extra_isize;
1124 
1125 	/* Indicate the inline data space. */
1126 	u16 i_inline_off;
1127 	u16 i_inline_size;
1128 
1129 #ifdef CONFIG_QUOTA
1130 	/* quota space reservation, managed internally by quota code */
1131 	qsize_t i_reserved_quota;
1132 #endif
1133 
1134 	/* Lock protecting lists below */
1135 	spinlock_t i_completed_io_lock;
1136 	/*
1137 	 * Completed IOs that need unwritten extents handling and have
1138 	 * transaction reserved
1139 	 */
1140 	struct list_head i_rsv_conversion_list;
1141 	struct work_struct i_rsv_conversion_work;
1142 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1143 
1144 	spinlock_t i_block_reservation_lock;
1145 
1146 	/*
1147 	 * Transactions that contain inode's metadata needed to complete
1148 	 * fsync and fdatasync, respectively.
1149 	 */
1150 	tid_t i_sync_tid;
1151 	tid_t i_datasync_tid;
1152 
1153 #ifdef CONFIG_QUOTA
1154 	struct dquot *i_dquot[MAXQUOTAS];
1155 #endif
1156 
1157 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1158 	__u32 i_csum_seed;
1159 
1160 	kprojid_t i_projid;
1161 };
1162 
1163 /*
1164  * File system states
1165  */
1166 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1167 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1168 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1169 #define EXT4_FC_REPLAY			0x0020	/* Fast commit replay ongoing */
1170 
1171 /*
1172  * Misc. filesystem flags
1173  */
1174 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1175 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1176 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1177 
1178 /*
1179  * Mount flags set via mount options or defaults
1180  */
1181 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1182 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1183 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1184 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1185 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1186 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1187 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1188 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1189 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1190 #ifdef CONFIG_FS_DAX
1191 #define EXT4_MOUNT_DAX_ALWAYS		0x00200	/* Direct Access */
1192 #else
1193 #define EXT4_MOUNT_DAX_ALWAYS		0
1194 #endif
1195 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1196 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1197 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1198 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1199 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1200 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1201 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1202 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1203 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1204 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1205 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1206 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1207 						 * enable enforcement for hidden
1208 						 * quota files */
1209 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1210 						  * enforcement for hidden quota
1211 						  * files */
1212 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1213 						  * enforcement */
1214 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1215 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1216 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1217 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
1218 #define EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS 0x4000000
1219 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1220 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1221 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1222 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1223 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1224 
1225 /*
1226  * Mount flags set either automatically (could not be set by mount option)
1227  * based on per file system feature or property or in special cases such as
1228  * distinguishing between explicit mount option definition and default.
1229  */
1230 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1231 						      specified delalloc */
1232 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1233 						      size of blocksize * 8
1234 						      blocks */
1235 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1236 						      file systems */
1237 #define EXT4_MOUNT2_DAX_NEVER		0x00000008 /* Do not allow Direct Access */
1238 #define EXT4_MOUNT2_DAX_INODE		0x00000010 /* For printing options only */
1239 
1240 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1241 						specified journal checksum */
1242 
1243 #define EXT4_MOUNT2_JOURNAL_FAST_COMMIT	0x00000010 /* Journal fast commit */
1244 
1245 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1246 						~EXT4_MOUNT_##opt
1247 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1248 						EXT4_MOUNT_##opt
1249 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1250 					 EXT4_MOUNT_##opt)
1251 
1252 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1253 						~EXT4_MOUNT2_##opt
1254 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1255 						EXT4_MOUNT2_##opt
1256 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1257 					 EXT4_MOUNT2_##opt)
1258 
1259 #define ext4_test_and_set_bit		__test_and_set_bit_le
1260 #define ext4_set_bit			__set_bit_le
1261 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1262 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1263 #define ext4_clear_bit			__clear_bit_le
1264 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1265 #define ext4_test_bit			test_bit_le
1266 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1267 #define ext4_find_next_bit		find_next_bit_le
1268 
1269 extern void ext4_set_bits(void *bm, int cur, int len);
1270 
1271 /*
1272  * Maximal mount counts between two filesystem checks
1273  */
1274 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1275 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1276 
1277 /*
1278  * Behaviour when detecting errors
1279  */
1280 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1281 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1282 #define EXT4_ERRORS_PANIC		3	/* Panic */
1283 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1284 
1285 /* Metadata checksum algorithm codes */
1286 #define EXT4_CRC32C_CHKSUM		1
1287 
1288 /*
1289  * Structure of the super block
1290  */
1291 struct ext4_super_block {
1292 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1293 	__le32	s_blocks_count_lo;	/* Blocks count */
1294 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1295 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1296 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1297 	__le32	s_first_data_block;	/* First Data Block */
1298 	__le32	s_log_block_size;	/* Block size */
1299 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1300 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1301 	__le32	s_clusters_per_group;	/* # Clusters per group */
1302 	__le32	s_inodes_per_group;	/* # Inodes per group */
1303 	__le32	s_mtime;		/* Mount time */
1304 /*30*/	__le32	s_wtime;		/* Write time */
1305 	__le16	s_mnt_count;		/* Mount count */
1306 	__le16	s_max_mnt_count;	/* Maximal mount count */
1307 	__le16	s_magic;		/* Magic signature */
1308 	__le16	s_state;		/* File system state */
1309 	__le16	s_errors;		/* Behaviour when detecting errors */
1310 	__le16	s_minor_rev_level;	/* minor revision level */
1311 /*40*/	__le32	s_lastcheck;		/* time of last check */
1312 	__le32	s_checkinterval;	/* max. time between checks */
1313 	__le32	s_creator_os;		/* OS */
1314 	__le32	s_rev_level;		/* Revision level */
1315 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1316 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1317 	/*
1318 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1319 	 *
1320 	 * Note: the difference between the compatible feature set and
1321 	 * the incompatible feature set is that if there is a bit set
1322 	 * in the incompatible feature set that the kernel doesn't
1323 	 * know about, it should refuse to mount the filesystem.
1324 	 *
1325 	 * e2fsck's requirements are more strict; if it doesn't know
1326 	 * about a feature in either the compatible or incompatible
1327 	 * feature set, it must abort and not try to meddle with
1328 	 * things it doesn't understand...
1329 	 */
1330 	__le32	s_first_ino;		/* First non-reserved inode */
1331 	__le16  s_inode_size;		/* size of inode structure */
1332 	__le16	s_block_group_nr;	/* block group # of this superblock */
1333 	__le32	s_feature_compat;	/* compatible feature set */
1334 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1335 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1336 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1337 /*78*/	char	s_volume_name[16];	/* volume name */
1338 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
1339 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1340 	/*
1341 	 * Performance hints.  Directory preallocation should only
1342 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1343 	 */
1344 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1345 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1346 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1347 	/*
1348 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1349 	 */
1350 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1351 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1352 	__le32	s_journal_dev;		/* device number of journal file */
1353 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1354 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1355 	__u8	s_def_hash_version;	/* Default hash version to use */
1356 	__u8	s_jnl_backup_type;
1357 	__le16  s_desc_size;		/* size of group descriptor */
1358 /*100*/	__le32	s_default_mount_opts;
1359 	__le32	s_first_meta_bg;	/* First metablock block group */
1360 	__le32	s_mkfs_time;		/* When the filesystem was created */
1361 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1362 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1363 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1364 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1365 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1366 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1367 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1368 	__le32	s_flags;		/* Miscellaneous flags */
1369 	__le16  s_raid_stride;		/* RAID stride */
1370 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1371 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1372 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1373 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1374 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1375 	__u8	s_encryption_level;	/* versioning level for encryption */
1376 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1377 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1378 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1379 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1380 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1381 					      snapshot's future use */
1382 	__le32	s_snapshot_list;	/* inode number of the head of the
1383 					   on-disk snapshot list */
1384 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1385 	__le32	s_error_count;		/* number of fs errors */
1386 	__le32	s_first_error_time;	/* first time an error happened */
1387 	__le32	s_first_error_ino;	/* inode involved in first error */
1388 	__le64	s_first_error_block;	/* block involved of first error */
1389 	__u8	s_first_error_func[32] __nonstring;	/* function where the error happened */
1390 	__le32	s_first_error_line;	/* line number where error happened */
1391 	__le32	s_last_error_time;	/* most recent time of an error */
1392 	__le32	s_last_error_ino;	/* inode involved in last error */
1393 	__le32	s_last_error_line;	/* line number where error happened */
1394 	__le64	s_last_error_block;	/* block involved of last error */
1395 	__u8	s_last_error_func[32] __nonstring;	/* function where the error happened */
1396 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1397 	__u8	s_mount_opts[64];
1398 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1399 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1400 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1401 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1402 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1403 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1404 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1405 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1406 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1407 	__u8	s_wtime_hi;
1408 	__u8	s_mtime_hi;
1409 	__u8	s_mkfs_time_hi;
1410 	__u8	s_lastcheck_hi;
1411 	__u8	s_first_error_time_hi;
1412 	__u8	s_last_error_time_hi;
1413 	__u8	s_first_error_errcode;
1414 	__u8    s_last_error_errcode;
1415 	__le16  s_encoding;		/* Filename charset encoding */
1416 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
1417 	__le32	s_reserved[95];		/* Padding to the end of the block */
1418 	__le32	s_checksum;		/* crc32c(superblock) */
1419 };
1420 
1421 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1422 
1423 #ifdef __KERNEL__
1424 
1425 /*
1426  * run-time mount flags
1427  */
1428 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1429 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1430 #define EXT4_MF_FC_INELIGIBLE		0x0004	/* Fast commit ineligible */
1431 #define EXT4_MF_FC_COMMITTING		0x0008	/* File system underoing a fast
1432 						 * commit.
1433 						 */
1434 
1435 #ifdef CONFIG_FS_ENCRYPTION
1436 #define DUMMY_ENCRYPTION_ENABLED(sbi) ((sbi)->s_dummy_enc_policy.policy != NULL)
1437 #else
1438 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1439 #endif
1440 
1441 /* Number of quota types we support */
1442 #define EXT4_MAXQUOTAS 3
1443 
1444 #define EXT4_ENC_UTF8_12_1	1
1445 
1446 /*
1447  * fourth extended-fs super-block data in memory
1448  */
1449 struct ext4_sb_info {
1450 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1451 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1452 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1453 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1454 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1455 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1456 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1457 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1458 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1459 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1460 	unsigned long s_overhead;  /* # of fs overhead clusters */
1461 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1462 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1463 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1464 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1465 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1466 	struct buffer_head * __rcu *s_group_desc;
1467 	unsigned int s_mount_opt;
1468 	unsigned int s_mount_opt2;
1469 	unsigned int s_mount_flags;
1470 	unsigned int s_def_mount_opt;
1471 	ext4_fsblk_t s_sb_block;
1472 	atomic64_t s_resv_clusters;
1473 	kuid_t s_resuid;
1474 	kgid_t s_resgid;
1475 	unsigned short s_mount_state;
1476 	unsigned short s_pad;
1477 	int s_addr_per_block_bits;
1478 	int s_desc_per_block_bits;
1479 	int s_inode_size;
1480 	int s_first_ino;
1481 	unsigned int s_inode_readahead_blks;
1482 	unsigned int s_inode_goal;
1483 	u32 s_hash_seed[4];
1484 	int s_def_hash_version;
1485 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1486 	struct percpu_counter s_freeclusters_counter;
1487 	struct percpu_counter s_freeinodes_counter;
1488 	struct percpu_counter s_dirs_counter;
1489 	struct percpu_counter s_dirtyclusters_counter;
1490 	struct blockgroup_lock *s_blockgroup_lock;
1491 	struct proc_dir_entry *s_proc;
1492 	struct kobject s_kobj;
1493 	struct completion s_kobj_unregister;
1494 	struct super_block *s_sb;
1495 
1496 	/* Journaling */
1497 	struct journal_s *s_journal;
1498 	struct list_head s_orphan;
1499 	struct mutex s_orphan_lock;
1500 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1501 	unsigned long s_commit_interval;
1502 	u32 s_max_batch_time;
1503 	u32 s_min_batch_time;
1504 	struct block_device *s_journal_bdev;
1505 #ifdef CONFIG_QUOTA
1506 	/* Names of quota files with journalled quota */
1507 	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1508 	int s_jquota_fmt;			/* Format of quota to use */
1509 #endif
1510 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1511 	struct ext4_system_blocks __rcu *s_system_blks;
1512 
1513 #ifdef EXTENTS_STATS
1514 	/* ext4 extents stats */
1515 	unsigned long s_ext_min;
1516 	unsigned long s_ext_max;
1517 	unsigned long s_depth_max;
1518 	spinlock_t s_ext_stats_lock;
1519 	unsigned long s_ext_blocks;
1520 	unsigned long s_ext_extents;
1521 #endif
1522 
1523 	/* for buddy allocator */
1524 	struct ext4_group_info ** __rcu *s_group_info;
1525 	struct inode *s_buddy_cache;
1526 	spinlock_t s_md_lock;
1527 	unsigned short *s_mb_offsets;
1528 	unsigned int *s_mb_maxs;
1529 	unsigned int s_group_info_size;
1530 	unsigned int s_mb_free_pending;
1531 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1532 						   after commit completed */
1533 
1534 	/* tunables */
1535 	unsigned long s_stripe;
1536 	unsigned int s_mb_stream_request;
1537 	unsigned int s_mb_max_to_scan;
1538 	unsigned int s_mb_min_to_scan;
1539 	unsigned int s_mb_stats;
1540 	unsigned int s_mb_order2_reqs;
1541 	unsigned int s_mb_group_prealloc;
1542 	unsigned int s_mb_max_inode_prealloc;
1543 	unsigned int s_max_dir_size_kb;
1544 	/* where last allocation was done - for stream allocation */
1545 	unsigned long s_mb_last_group;
1546 	unsigned long s_mb_last_start;
1547 	unsigned int s_mb_prefetch;
1548 	unsigned int s_mb_prefetch_limit;
1549 
1550 	/* stats for buddy allocator */
1551 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1552 	atomic_t s_bal_success;	/* we found long enough chunks */
1553 	atomic_t s_bal_allocated;	/* in blocks */
1554 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1555 	atomic_t s_bal_goals;	/* goal hits */
1556 	atomic_t s_bal_breaks;	/* too long searches */
1557 	atomic_t s_bal_2orders;	/* 2^order hits */
1558 	spinlock_t s_bal_lock;
1559 	unsigned long s_mb_buddies_generated;
1560 	unsigned long long s_mb_generation_time;
1561 	atomic_t s_mb_lost_chunks;
1562 	atomic_t s_mb_preallocated;
1563 	atomic_t s_mb_discarded;
1564 	atomic_t s_lock_busy;
1565 
1566 	/* locality groups */
1567 	struct ext4_locality_group __percpu *s_locality_groups;
1568 
1569 	/* for write statistics */
1570 	unsigned long s_sectors_written_start;
1571 	u64 s_kbytes_written;
1572 
1573 	/* the size of zero-out chunk */
1574 	unsigned int s_extent_max_zeroout_kb;
1575 
1576 	unsigned int s_log_groups_per_flex;
1577 	struct flex_groups * __rcu *s_flex_groups;
1578 	ext4_group_t s_flex_groups_allocated;
1579 
1580 	/* workqueue for reserved extent conversions (buffered io) */
1581 	struct workqueue_struct *rsv_conversion_wq;
1582 
1583 	/* timer for periodic error stats printing */
1584 	struct timer_list s_err_report;
1585 
1586 	/* Lazy inode table initialization info */
1587 	struct ext4_li_request *s_li_request;
1588 	/* Wait multiplier for lazy initialization thread */
1589 	unsigned int s_li_wait_mult;
1590 
1591 	/* Kernel thread for multiple mount protection */
1592 	struct task_struct *s_mmp_tsk;
1593 
1594 	/* record the last minlen when FITRIM is called. */
1595 	atomic_t s_last_trim_minblks;
1596 
1597 	/* Reference to checksum algorithm driver via cryptoapi */
1598 	struct crypto_shash *s_chksum_driver;
1599 
1600 	/* Precomputed FS UUID checksum for seeding other checksums */
1601 	__u32 s_csum_seed;
1602 
1603 	/* Reclaim extents from extent status tree */
1604 	struct shrinker s_es_shrinker;
1605 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1606 	long s_es_nr_inode;
1607 	struct ext4_es_stats s_es_stats;
1608 	struct mb_cache *s_ea_block_cache;
1609 	struct mb_cache *s_ea_inode_cache;
1610 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1611 
1612 	/* Ratelimit ext4 messages. */
1613 	struct ratelimit_state s_err_ratelimit_state;
1614 	struct ratelimit_state s_warning_ratelimit_state;
1615 	struct ratelimit_state s_msg_ratelimit_state;
1616 	atomic_t s_warning_count;
1617 	atomic_t s_msg_count;
1618 
1619 	/* Encryption policy for '-o test_dummy_encryption' */
1620 	struct fscrypt_dummy_policy s_dummy_enc_policy;
1621 
1622 	/*
1623 	 * Barrier between writepages ops and changing any inode's JOURNAL_DATA
1624 	 * or EXTENTS flag.
1625 	 */
1626 	struct percpu_rw_semaphore s_writepages_rwsem;
1627 	struct dax_device *s_daxdev;
1628 #ifdef CONFIG_EXT4_DEBUG
1629 	unsigned long s_simulate_fail;
1630 #endif
1631 	/* Record the errseq of the backing block device */
1632 	errseq_t s_bdev_wb_err;
1633 	spinlock_t s_bdev_wb_lock;
1634 
1635 	/* Ext4 fast commit stuff */
1636 	atomic_t s_fc_subtid;
1637 	atomic_t s_fc_ineligible_updates;
1638 	/*
1639 	 * After commit starts, the main queue gets locked, and the further
1640 	 * updates get added in the staging queue.
1641 	 */
1642 #define FC_Q_MAIN	0
1643 #define FC_Q_STAGING	1
1644 	struct list_head s_fc_q[2];	/* Inodes staged for fast commit
1645 					 * that have data changes in them.
1646 					 */
1647 	struct list_head s_fc_dentry_q[2];	/* directory entry updates */
1648 	unsigned int s_fc_bytes;
1649 	/*
1650 	 * Main fast commit lock. This lock protects accesses to the
1651 	 * following fields:
1652 	 * ei->i_fc_list, s_fc_dentry_q, s_fc_q, s_fc_bytes, s_fc_bh.
1653 	 */
1654 	spinlock_t s_fc_lock;
1655 	struct buffer_head *s_fc_bh;
1656 	struct ext4_fc_stats s_fc_stats;
1657 	u64 s_fc_avg_commit_time;
1658 #ifdef CONFIG_EXT4_DEBUG
1659 	int s_fc_debug_max_replay;
1660 #endif
1661 	struct ext4_fc_replay_state s_fc_replay_state;
1662 };
1663 
1664 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1665 {
1666 	return sb->s_fs_info;
1667 }
1668 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1669 {
1670 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1671 }
1672 
1673 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1674 {
1675 	return ino == EXT4_ROOT_INO ||
1676 		(ino >= EXT4_FIRST_INO(sb) &&
1677 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1678 }
1679 
1680 /*
1681  * Returns: sbi->field[index]
1682  * Used to access an array element from the following sbi fields which require
1683  * rcu protection to avoid dereferencing an invalid pointer due to reassignment
1684  * - s_group_desc
1685  * - s_group_info
1686  * - s_flex_group
1687  */
1688 #define sbi_array_rcu_deref(sbi, field, index)				   \
1689 ({									   \
1690 	typeof(*((sbi)->field)) _v;					   \
1691 	rcu_read_lock();						   \
1692 	_v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index];	   \
1693 	rcu_read_unlock();						   \
1694 	_v;								   \
1695 })
1696 
1697 /*
1698  * Simulate_fail codes
1699  */
1700 #define EXT4_SIM_BBITMAP_EIO	1
1701 #define EXT4_SIM_BBITMAP_CRC	2
1702 #define EXT4_SIM_IBITMAP_EIO	3
1703 #define EXT4_SIM_IBITMAP_CRC	4
1704 #define EXT4_SIM_INODE_EIO	5
1705 #define EXT4_SIM_INODE_CRC	6
1706 #define EXT4_SIM_DIRBLOCK_EIO	7
1707 #define EXT4_SIM_DIRBLOCK_CRC	8
1708 
1709 static inline bool ext4_simulate_fail(struct super_block *sb,
1710 				     unsigned long code)
1711 {
1712 #ifdef CONFIG_EXT4_DEBUG
1713 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1714 
1715 	if (unlikely(sbi->s_simulate_fail == code)) {
1716 		sbi->s_simulate_fail = 0;
1717 		return true;
1718 	}
1719 #endif
1720 	return false;
1721 }
1722 
1723 static inline void ext4_simulate_fail_bh(struct super_block *sb,
1724 					 struct buffer_head *bh,
1725 					 unsigned long code)
1726 {
1727 	if (!IS_ERR(bh) && ext4_simulate_fail(sb, code))
1728 		clear_buffer_uptodate(bh);
1729 }
1730 
1731 /*
1732  * Error number codes for s_{first,last}_error_errno
1733  *
1734  * Linux errno numbers are architecture specific, so we need to translate
1735  * them into something which is architecture independent.   We don't define
1736  * codes for all errno's; just the ones which are most likely to be the cause
1737  * of an ext4_error() call.
1738  */
1739 #define EXT4_ERR_UNKNOWN	 1
1740 #define EXT4_ERR_EIO		 2
1741 #define EXT4_ERR_ENOMEM		 3
1742 #define EXT4_ERR_EFSBADCRC	 4
1743 #define EXT4_ERR_EFSCORRUPTED	 5
1744 #define EXT4_ERR_ENOSPC		 6
1745 #define EXT4_ERR_ENOKEY		 7
1746 #define EXT4_ERR_EROFS		 8
1747 #define EXT4_ERR_EFBIG		 9
1748 #define EXT4_ERR_EEXIST		10
1749 #define EXT4_ERR_ERANGE		11
1750 #define EXT4_ERR_EOVERFLOW	12
1751 #define EXT4_ERR_EBUSY		13
1752 #define EXT4_ERR_ENOTDIR	14
1753 #define EXT4_ERR_ENOTEMPTY	15
1754 #define EXT4_ERR_ESHUTDOWN	16
1755 #define EXT4_ERR_EFAULT		17
1756 
1757 /*
1758  * Inode dynamic state flags
1759  */
1760 enum {
1761 	EXT4_STATE_JDATA,		/* journaled data exists */
1762 	EXT4_STATE_NEW,			/* inode is newly created */
1763 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1764 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1765 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1766 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1767 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1768 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1769 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1770 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1771 	EXT4_STATE_VERITY_IN_PROGRESS,	/* building fs-verity Merkle tree */
1772 	EXT4_STATE_FC_COMMITTING,	/* Fast commit ongoing */
1773 };
1774 
1775 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1776 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1777 {									\
1778 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1779 }									\
1780 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1781 {									\
1782 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1783 }									\
1784 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1785 {									\
1786 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1787 }
1788 
1789 /* Add these declarations here only so that these functions can be
1790  * found by name.  Otherwise, they are very hard to locate. */
1791 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1792 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1793 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1794 EXT4_INODE_BIT_FNS(flag, flags, 0)
1795 
1796 /* Add these declarations here only so that these functions can be
1797  * found by name.  Otherwise, they are very hard to locate. */
1798 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1799 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1800 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1801 #if (BITS_PER_LONG < 64)
1802 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1803 
1804 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1805 {
1806 	(ei)->i_state_flags = 0;
1807 }
1808 #else
1809 EXT4_INODE_BIT_FNS(state, flags, 32)
1810 
1811 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1812 {
1813 	/* We depend on the fact that callers will set i_flags */
1814 }
1815 #endif
1816 #else
1817 /* Assume that user mode programs are passing in an ext4fs superblock, not
1818  * a kernel struct super_block.  This will allow us to call the feature-test
1819  * macros from user land. */
1820 #define EXT4_SB(sb)	(sb)
1821 #endif
1822 
1823 static inline bool ext4_verity_in_progress(struct inode *inode)
1824 {
1825 	return IS_ENABLED(CONFIG_FS_VERITY) &&
1826 	       ext4_test_inode_state(inode, EXT4_STATE_VERITY_IN_PROGRESS);
1827 }
1828 
1829 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1830 
1831 /*
1832  * Codes for operating systems
1833  */
1834 #define EXT4_OS_LINUX		0
1835 #define EXT4_OS_HURD		1
1836 #define EXT4_OS_MASIX		2
1837 #define EXT4_OS_FREEBSD		3
1838 #define EXT4_OS_LITES		4
1839 
1840 /*
1841  * Revision levels
1842  */
1843 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1844 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1845 
1846 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1847 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1848 
1849 #define EXT4_GOOD_OLD_INODE_SIZE 128
1850 
1851 #define EXT4_EXTRA_TIMESTAMP_MAX	(((s64)1 << 34) - 1  + S32_MIN)
1852 #define EXT4_NON_EXTRA_TIMESTAMP_MAX	S32_MAX
1853 #define EXT4_TIMESTAMP_MIN		S32_MIN
1854 
1855 /*
1856  * Feature set definitions
1857  */
1858 
1859 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1860 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1861 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1862 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1863 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1864 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1865 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1866 #define EXT4_FEATURE_COMPAT_FAST_COMMIT		0x0400
1867 #define EXT4_FEATURE_COMPAT_STABLE_INODES	0x0800
1868 
1869 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1870 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1871 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1872 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1873 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1874 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1875 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1876 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1877 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1878 /*
1879  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1880  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1881  * all other data structures' checksums.  However, the METADATA_CSUM and
1882  * GDT_CSUM bits are mutually exclusive.
1883  */
1884 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1885 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1886 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1887 #define EXT4_FEATURE_RO_COMPAT_VERITY		0x8000
1888 
1889 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1890 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1891 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1892 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1893 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1894 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1895 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1896 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1897 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1898 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1899 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1900 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1901 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1902 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1903 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1904 #define EXT4_FEATURE_INCOMPAT_CASEFOLD		0x20000
1905 
1906 extern void ext4_update_dynamic_rev(struct super_block *sb);
1907 
1908 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1909 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1910 { \
1911 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1912 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1913 } \
1914 static inline void ext4_set_feature_##name(struct super_block *sb) \
1915 { \
1916 	ext4_update_dynamic_rev(sb); \
1917 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1918 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1919 } \
1920 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1921 { \
1922 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1923 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1924 }
1925 
1926 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1927 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1928 { \
1929 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1930 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1931 } \
1932 static inline void ext4_set_feature_##name(struct super_block *sb) \
1933 { \
1934 	ext4_update_dynamic_rev(sb); \
1935 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1936 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1937 } \
1938 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1939 { \
1940 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1941 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1942 }
1943 
1944 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1945 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1946 { \
1947 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1948 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1949 } \
1950 static inline void ext4_set_feature_##name(struct super_block *sb) \
1951 { \
1952 	ext4_update_dynamic_rev(sb); \
1953 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
1954 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1955 } \
1956 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1957 { \
1958 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1959 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1960 }
1961 
1962 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1963 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1964 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1965 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1966 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1967 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1968 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1969 EXT4_FEATURE_COMPAT_FUNCS(fast_commit,		FAST_COMMIT)
1970 EXT4_FEATURE_COMPAT_FUNCS(stable_inodes,	STABLE_INODES)
1971 
1972 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1973 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1974 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1975 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1976 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1977 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1978 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1979 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1980 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1981 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1982 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1983 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1984 EXT4_FEATURE_RO_COMPAT_FUNCS(verity,		VERITY)
1985 
1986 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1987 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
1988 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
1989 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
1990 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
1991 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
1992 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
1993 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
1994 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
1995 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
1996 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
1997 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
1998 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
1999 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
2000 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
2001 EXT4_FEATURE_INCOMPAT_FUNCS(casefold,		CASEFOLD)
2002 
2003 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2004 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2005 					 EXT4_FEATURE_INCOMPAT_META_BG)
2006 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2007 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2008 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2009 
2010 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2011 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2012 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
2013 					 EXT4_FEATURE_INCOMPAT_META_BG)
2014 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2015 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2016 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2017 
2018 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2019 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2020 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
2021 					 EXT4_FEATURE_INCOMPAT_META_BG| \
2022 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
2023 					 EXT4_FEATURE_INCOMPAT_64BIT| \
2024 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
2025 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
2026 					 EXT4_FEATURE_INCOMPAT_MMP | \
2027 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
2028 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
2029 					 EXT4_FEATURE_INCOMPAT_CASEFOLD | \
2030 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
2031 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
2032 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2033 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2034 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
2035 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
2036 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
2037 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
2038 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
2039 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
2040 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
2041 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
2042 					 EXT4_FEATURE_RO_COMPAT_PROJECT |\
2043 					 EXT4_FEATURE_RO_COMPAT_VERITY)
2044 
2045 #define EXTN_FEATURE_FUNCS(ver) \
2046 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
2047 { \
2048 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
2049 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
2050 } \
2051 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
2052 { \
2053 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2054 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
2055 } \
2056 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
2057 { \
2058 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2059 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
2060 }
2061 
2062 EXTN_FEATURE_FUNCS(2)
2063 EXTN_FEATURE_FUNCS(3)
2064 EXTN_FEATURE_FUNCS(4)
2065 
2066 static inline bool ext4_has_compat_features(struct super_block *sb)
2067 {
2068 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
2069 }
2070 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
2071 {
2072 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
2073 }
2074 static inline bool ext4_has_incompat_features(struct super_block *sb)
2075 {
2076 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
2077 }
2078 
2079 /*
2080  * Superblock flags
2081  */
2082 #define EXT4_FLAGS_RESIZING	0
2083 #define EXT4_FLAGS_SHUTDOWN	1
2084 #define EXT4_FLAGS_BDEV_IS_DAX	2
2085 
2086 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
2087 {
2088 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
2089 }
2090 
2091 
2092 /*
2093  * Default values for user and/or group using reserved blocks
2094  */
2095 #define	EXT4_DEF_RESUID		0
2096 #define	EXT4_DEF_RESGID		0
2097 
2098 /*
2099  * Default project ID
2100  */
2101 #define	EXT4_DEF_PROJID		0
2102 
2103 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
2104 
2105 /*
2106  * Default mount options
2107  */
2108 #define EXT4_DEFM_DEBUG		0x0001
2109 #define EXT4_DEFM_BSDGROUPS	0x0002
2110 #define EXT4_DEFM_XATTR_USER	0x0004
2111 #define EXT4_DEFM_ACL		0x0008
2112 #define EXT4_DEFM_UID16		0x0010
2113 #define EXT4_DEFM_JMODE		0x0060
2114 #define EXT4_DEFM_JMODE_DATA	0x0020
2115 #define EXT4_DEFM_JMODE_ORDERED	0x0040
2116 #define EXT4_DEFM_JMODE_WBACK	0x0060
2117 #define EXT4_DEFM_NOBARRIER	0x0100
2118 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
2119 #define EXT4_DEFM_DISCARD	0x0400
2120 #define EXT4_DEFM_NODELALLOC	0x0800
2121 
2122 /*
2123  * Default journal batch times
2124  */
2125 #define EXT4_DEF_MIN_BATCH_TIME	0
2126 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
2127 
2128 /*
2129  * Minimum number of groups in a flexgroup before we separate out
2130  * directories into the first block group of a flexgroup
2131  */
2132 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
2133 
2134 /*
2135  * Structure of a directory entry
2136  */
2137 #define EXT4_NAME_LEN 255
2138 
2139 struct ext4_dir_entry {
2140 	__le32	inode;			/* Inode number */
2141 	__le16	rec_len;		/* Directory entry length */
2142 	__le16	name_len;		/* Name length */
2143 	char	name[EXT4_NAME_LEN];	/* File name */
2144 };
2145 
2146 /*
2147  * The new version of the directory entry.  Since EXT4 structures are
2148  * stored in intel byte order, and the name_len field could never be
2149  * bigger than 255 chars, it's safe to reclaim the extra byte for the
2150  * file_type field.
2151  */
2152 struct ext4_dir_entry_2 {
2153 	__le32	inode;			/* Inode number */
2154 	__le16	rec_len;		/* Directory entry length */
2155 	__u8	name_len;		/* Name length */
2156 	__u8	file_type;		/* See file type macros EXT4_FT_* below */
2157 	char	name[EXT4_NAME_LEN];	/* File name */
2158 };
2159 
2160 /*
2161  * This is a bogus directory entry at the end of each leaf block that
2162  * records checksums.
2163  */
2164 struct ext4_dir_entry_tail {
2165 	__le32	det_reserved_zero1;	/* Pretend to be unused */
2166 	__le16	det_rec_len;		/* 12 */
2167 	__u8	det_reserved_zero2;	/* Zero name length */
2168 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
2169 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
2170 };
2171 
2172 #define EXT4_DIRENT_TAIL(block, blocksize) \
2173 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
2174 					((blocksize) - \
2175 					 sizeof(struct ext4_dir_entry_tail))))
2176 
2177 /*
2178  * Ext4 directory file types.  Only the low 3 bits are used.  The
2179  * other bits are reserved for now.
2180  */
2181 #define EXT4_FT_UNKNOWN		0
2182 #define EXT4_FT_REG_FILE	1
2183 #define EXT4_FT_DIR		2
2184 #define EXT4_FT_CHRDEV		3
2185 #define EXT4_FT_BLKDEV		4
2186 #define EXT4_FT_FIFO		5
2187 #define EXT4_FT_SOCK		6
2188 #define EXT4_FT_SYMLINK		7
2189 
2190 #define EXT4_FT_MAX		8
2191 
2192 #define EXT4_FT_DIR_CSUM	0xDE
2193 
2194 /*
2195  * EXT4_DIR_PAD defines the directory entries boundaries
2196  *
2197  * NOTE: It must be a multiple of 4
2198  */
2199 #define EXT4_DIR_PAD			4
2200 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
2201 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
2202 					 ~EXT4_DIR_ROUND)
2203 #define EXT4_MAX_REC_LEN		((1<<16)-1)
2204 
2205 /*
2206  * If we ever get support for fs block sizes > page_size, we'll need
2207  * to remove the #if statements in the next two functions...
2208  */
2209 static inline unsigned int
2210 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
2211 {
2212 	unsigned len = le16_to_cpu(dlen);
2213 
2214 #if (PAGE_SIZE >= 65536)
2215 	if (len == EXT4_MAX_REC_LEN || len == 0)
2216 		return blocksize;
2217 	return (len & 65532) | ((len & 3) << 16);
2218 #else
2219 	return len;
2220 #endif
2221 }
2222 
2223 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2224 {
2225 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
2226 		BUG();
2227 #if (PAGE_SIZE >= 65536)
2228 	if (len < 65536)
2229 		return cpu_to_le16(len);
2230 	if (len == blocksize) {
2231 		if (blocksize == 65536)
2232 			return cpu_to_le16(EXT4_MAX_REC_LEN);
2233 		else
2234 			return cpu_to_le16(0);
2235 	}
2236 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2237 #else
2238 	return cpu_to_le16(len);
2239 #endif
2240 }
2241 
2242 /*
2243  * Hash Tree Directory indexing
2244  * (c) Daniel Phillips, 2001
2245  */
2246 
2247 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2248 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2249 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2250 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2251 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2252 
2253 /* Legal values for the dx_root hash_version field: */
2254 
2255 #define DX_HASH_LEGACY			0
2256 #define DX_HASH_HALF_MD4		1
2257 #define DX_HASH_TEA			2
2258 #define DX_HASH_LEGACY_UNSIGNED		3
2259 #define DX_HASH_HALF_MD4_UNSIGNED	4
2260 #define DX_HASH_TEA_UNSIGNED		5
2261 
2262 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2263 			      const void *address, unsigned int length)
2264 {
2265 	struct {
2266 		struct shash_desc shash;
2267 		char ctx[4];
2268 	} desc;
2269 
2270 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2271 
2272 	desc.shash.tfm = sbi->s_chksum_driver;
2273 	*(u32 *)desc.ctx = crc;
2274 
2275 	BUG_ON(crypto_shash_update(&desc.shash, address, length));
2276 
2277 	return *(u32 *)desc.ctx;
2278 }
2279 
2280 #ifdef __KERNEL__
2281 
2282 /* hash info structure used by the directory hash */
2283 struct dx_hash_info
2284 {
2285 	u32		hash;
2286 	u32		minor_hash;
2287 	int		hash_version;
2288 	u32		*seed;
2289 };
2290 
2291 
2292 /* 32 and 64 bit signed EOF for dx directories */
2293 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2294 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2295 
2296 
2297 /*
2298  * Control parameters used by ext4_htree_next_block
2299  */
2300 #define HASH_NB_ALWAYS		1
2301 
2302 struct ext4_filename {
2303 	const struct qstr *usr_fname;
2304 	struct fscrypt_str disk_name;
2305 	struct dx_hash_info hinfo;
2306 #ifdef CONFIG_FS_ENCRYPTION
2307 	struct fscrypt_str crypto_buf;
2308 #endif
2309 #ifdef CONFIG_UNICODE
2310 	struct fscrypt_str cf_name;
2311 #endif
2312 };
2313 
2314 #define fname_name(p) ((p)->disk_name.name)
2315 #define fname_len(p)  ((p)->disk_name.len)
2316 
2317 /*
2318  * Describe an inode's exact location on disk and in memory
2319  */
2320 struct ext4_iloc
2321 {
2322 	struct buffer_head *bh;
2323 	unsigned long offset;
2324 	ext4_group_t block_group;
2325 };
2326 
2327 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2328 {
2329 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2330 }
2331 
2332 static inline bool ext4_is_quota_file(struct inode *inode)
2333 {
2334 	return IS_NOQUOTA(inode) &&
2335 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2336 }
2337 
2338 /*
2339  * This structure is stuffed into the struct file's private_data field
2340  * for directories.  It is where we put information so that we can do
2341  * readdir operations in hash tree order.
2342  */
2343 struct dir_private_info {
2344 	struct rb_root	root;
2345 	struct rb_node	*curr_node;
2346 	struct fname	*extra_fname;
2347 	loff_t		last_pos;
2348 	__u32		curr_hash;
2349 	__u32		curr_minor_hash;
2350 	__u32		next_hash;
2351 };
2352 
2353 /* calculate the first block number of the group */
2354 static inline ext4_fsblk_t
2355 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2356 {
2357 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2358 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2359 }
2360 
2361 /*
2362  * Special error return code only used by dx_probe() and its callers.
2363  */
2364 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2365 
2366 /* htree levels for ext4 */
2367 #define	EXT4_HTREE_LEVEL_COMPAT	2
2368 #define	EXT4_HTREE_LEVEL	3
2369 
2370 static inline int ext4_dir_htree_level(struct super_block *sb)
2371 {
2372 	return ext4_has_feature_largedir(sb) ?
2373 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2374 }
2375 
2376 /*
2377  * Timeout and state flag for lazy initialization inode thread.
2378  */
2379 #define EXT4_DEF_LI_WAIT_MULT			10
2380 #define EXT4_DEF_LI_MAX_START_DELAY		5
2381 #define EXT4_LAZYINIT_QUIT			0x0001
2382 #define EXT4_LAZYINIT_RUNNING			0x0002
2383 
2384 /*
2385  * Lazy inode table initialization info
2386  */
2387 struct ext4_lazy_init {
2388 	unsigned long		li_state;
2389 	struct list_head	li_request_list;
2390 	struct mutex		li_list_mtx;
2391 };
2392 
2393 enum ext4_li_mode {
2394 	EXT4_LI_MODE_PREFETCH_BBITMAP,
2395 	EXT4_LI_MODE_ITABLE,
2396 };
2397 
2398 struct ext4_li_request {
2399 	struct super_block	*lr_super;
2400 	enum ext4_li_mode	lr_mode;
2401 	ext4_group_t		lr_first_not_zeroed;
2402 	ext4_group_t		lr_next_group;
2403 	struct list_head	lr_request;
2404 	unsigned long		lr_next_sched;
2405 	unsigned long		lr_timeout;
2406 };
2407 
2408 struct ext4_features {
2409 	struct kobject f_kobj;
2410 	struct completion f_kobj_unregister;
2411 };
2412 
2413 /*
2414  * This structure will be used for multiple mount protection. It will be
2415  * written into the block number saved in the s_mmp_block field in the
2416  * superblock. Programs that check MMP should assume that if
2417  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2418  * to use the filesystem, regardless of how old the timestamp is.
2419  */
2420 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2421 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2422 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2423 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2424 
2425 struct mmp_struct {
2426 	__le32	mmp_magic;		/* Magic number for MMP */
2427 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2428 
2429 	/*
2430 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2431 	 * purposes and do not affect the correctness of the algorithm
2432 	 */
2433 	__le64	mmp_time;		/* Time last updated */
2434 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2435 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2436 
2437 	/*
2438 	 * mmp_check_interval is used to verify if the MMP block has been
2439 	 * updated on the block device. The value is updated based on the
2440 	 * maximum time to write the MMP block during an update cycle.
2441 	 */
2442 	__le16	mmp_check_interval;
2443 
2444 	__le16	mmp_pad1;
2445 	__le32	mmp_pad2[226];
2446 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2447 };
2448 
2449 /* arguments passed to the mmp thread */
2450 struct mmpd_data {
2451 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2452 	struct super_block *sb;  /* super block of the fs */
2453 };
2454 
2455 /*
2456  * Check interval multiplier
2457  * The MMP block is written every update interval and initially checked every
2458  * update interval x the multiplier (the value is then adapted based on the
2459  * write latency). The reason is that writes can be delayed under load and we
2460  * don't want readers to incorrectly assume that the filesystem is no longer
2461  * in use.
2462  */
2463 #define EXT4_MMP_CHECK_MULT		2UL
2464 
2465 /*
2466  * Minimum interval for MMP checking in seconds.
2467  */
2468 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2469 
2470 /*
2471  * Maximum interval for MMP checking in seconds.
2472  */
2473 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2474 
2475 /*
2476  * Function prototypes
2477  */
2478 
2479 /*
2480  * Ok, these declarations are also in <linux/kernel.h> but none of the
2481  * ext4 source programs needs to include it so they are duplicated here.
2482  */
2483 # define NORET_TYPE	/**/
2484 # define ATTRIB_NORET	__attribute__((noreturn))
2485 # define NORET_AND	noreturn,
2486 
2487 /* bitmap.c */
2488 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2489 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2490 				struct ext4_group_desc *gdp,
2491 				struct buffer_head *bh, int sz);
2492 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2493 				  struct ext4_group_desc *gdp,
2494 				  struct buffer_head *bh, int sz);
2495 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2496 				struct ext4_group_desc *gdp,
2497 				struct buffer_head *bh);
2498 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2499 				  struct ext4_group_desc *gdp,
2500 				  struct buffer_head *bh);
2501 
2502 /* balloc.c */
2503 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2504 					 ext4_fsblk_t blocknr,
2505 					 ext4_group_t *blockgrpp,
2506 					 ext4_grpblk_t *offsetp);
2507 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2508 					  ext4_fsblk_t block);
2509 
2510 extern unsigned int ext4_block_group(struct super_block *sb,
2511 			ext4_fsblk_t blocknr);
2512 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2513 			ext4_fsblk_t blocknr);
2514 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2515 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2516 			ext4_group_t group);
2517 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2518 					 ext4_fsblk_t goal,
2519 					 unsigned int flags,
2520 					 unsigned long *count,
2521 					 int *errp);
2522 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2523 				    s64 nclusters, unsigned int flags);
2524 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2525 extern void ext4_check_blocks_bitmap(struct super_block *);
2526 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2527 						    ext4_group_t block_group,
2528 						    struct buffer_head ** bh);
2529 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2530 
2531 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2532 						ext4_group_t block_group,
2533 						bool ignore_locked);
2534 extern int ext4_wait_block_bitmap(struct super_block *sb,
2535 				  ext4_group_t block_group,
2536 				  struct buffer_head *bh);
2537 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2538 						  ext4_group_t block_group);
2539 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2540 					      ext4_group_t block_group,
2541 					      struct ext4_group_desc *gdp);
2542 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2543 
2544 #ifdef CONFIG_UNICODE
2545 extern void ext4_fname_setup_ci_filename(struct inode *dir,
2546 					 const struct qstr *iname,
2547 					 struct fscrypt_str *fname);
2548 #endif
2549 
2550 #ifdef CONFIG_FS_ENCRYPTION
2551 static inline void ext4_fname_from_fscrypt_name(struct ext4_filename *dst,
2552 						const struct fscrypt_name *src)
2553 {
2554 	memset(dst, 0, sizeof(*dst));
2555 
2556 	dst->usr_fname = src->usr_fname;
2557 	dst->disk_name = src->disk_name;
2558 	dst->hinfo.hash = src->hash;
2559 	dst->hinfo.minor_hash = src->minor_hash;
2560 	dst->crypto_buf = src->crypto_buf;
2561 }
2562 
2563 static inline int ext4_fname_setup_filename(struct inode *dir,
2564 					    const struct qstr *iname,
2565 					    int lookup,
2566 					    struct ext4_filename *fname)
2567 {
2568 	struct fscrypt_name name;
2569 	int err;
2570 
2571 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2572 	if (err)
2573 		return err;
2574 
2575 	ext4_fname_from_fscrypt_name(fname, &name);
2576 
2577 #ifdef CONFIG_UNICODE
2578 	ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name);
2579 #endif
2580 	return 0;
2581 }
2582 
2583 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2584 					    struct dentry *dentry,
2585 					    struct ext4_filename *fname)
2586 {
2587 	struct fscrypt_name name;
2588 	int err;
2589 
2590 	err = fscrypt_prepare_lookup(dir, dentry, &name);
2591 	if (err)
2592 		return err;
2593 
2594 	ext4_fname_from_fscrypt_name(fname, &name);
2595 
2596 #ifdef CONFIG_UNICODE
2597 	ext4_fname_setup_ci_filename(dir, &dentry->d_name, &fname->cf_name);
2598 #endif
2599 	return 0;
2600 }
2601 
2602 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2603 {
2604 	struct fscrypt_name name;
2605 
2606 	name.crypto_buf = fname->crypto_buf;
2607 	fscrypt_free_filename(&name);
2608 
2609 	fname->crypto_buf.name = NULL;
2610 	fname->usr_fname = NULL;
2611 	fname->disk_name.name = NULL;
2612 
2613 #ifdef CONFIG_UNICODE
2614 	kfree(fname->cf_name.name);
2615 	fname->cf_name.name = NULL;
2616 #endif
2617 }
2618 #else /* !CONFIG_FS_ENCRYPTION */
2619 static inline int ext4_fname_setup_filename(struct inode *dir,
2620 					    const struct qstr *iname,
2621 					    int lookup,
2622 					    struct ext4_filename *fname)
2623 {
2624 	fname->usr_fname = iname;
2625 	fname->disk_name.name = (unsigned char *) iname->name;
2626 	fname->disk_name.len = iname->len;
2627 
2628 #ifdef CONFIG_UNICODE
2629 	ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name);
2630 #endif
2631 
2632 	return 0;
2633 }
2634 
2635 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2636 					    struct dentry *dentry,
2637 					    struct ext4_filename *fname)
2638 {
2639 	return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
2640 }
2641 
2642 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2643 {
2644 #ifdef CONFIG_UNICODE
2645 	kfree(fname->cf_name.name);
2646 	fname->cf_name.name = NULL;
2647 #endif
2648 }
2649 #endif /* !CONFIG_FS_ENCRYPTION */
2650 
2651 /* dir.c */
2652 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2653 				  struct file *,
2654 				  struct ext4_dir_entry_2 *,
2655 				  struct buffer_head *, char *, int,
2656 				  unsigned int);
2657 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2658 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2659 					(de), (bh), (buf), (size), (offset)))
2660 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2661 				__u32 minor_hash,
2662 				struct ext4_dir_entry_2 *dirent,
2663 				struct fscrypt_str *ent_name);
2664 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2665 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2666 			     struct buffer_head *bh,
2667 			     void *buf, int buf_size,
2668 			     struct ext4_filename *fname,
2669 			     struct ext4_dir_entry_2 **dest_de);
2670 void ext4_insert_dentry(struct inode *inode,
2671 			struct ext4_dir_entry_2 *de,
2672 			int buf_size,
2673 			struct ext4_filename *fname);
2674 static inline void ext4_update_dx_flag(struct inode *inode)
2675 {
2676 	if (!ext4_has_feature_dir_index(inode->i_sb)) {
2677 		/* ext4_iget() should have caught this... */
2678 		WARN_ON_ONCE(ext4_has_feature_metadata_csum(inode->i_sb));
2679 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2680 	}
2681 }
2682 static const unsigned char ext4_filetype_table[] = {
2683 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2684 };
2685 
2686 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2687 {
2688 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2689 		return DT_UNKNOWN;
2690 
2691 	return ext4_filetype_table[filetype];
2692 }
2693 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2694 			     void *buf, int buf_size);
2695 
2696 /* fsync.c */
2697 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2698 
2699 /* hash.c */
2700 extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
2701 			  struct dx_hash_info *hinfo);
2702 
2703 /* ialloc.c */
2704 extern int ext4_mark_inode_used(struct super_block *sb, int ino);
2705 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2706 				      const struct qstr *qstr, __u32 goal,
2707 				      uid_t *owner, __u32 i_flags,
2708 				      int handle_type, unsigned int line_no,
2709 				      int nblocks);
2710 
2711 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2712 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2713 			 i_flags, 0, 0, 0)
2714 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2715 				    type, nblocks)		    \
2716 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2717 			 0, (type), __LINE__, (nblocks))
2718 
2719 
2720 extern void ext4_free_inode(handle_t *, struct inode *);
2721 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2722 extern unsigned long ext4_count_free_inodes(struct super_block *);
2723 extern unsigned long ext4_count_dirs(struct super_block *);
2724 extern void ext4_check_inodes_bitmap(struct super_block *);
2725 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2726 extern int ext4_init_inode_table(struct super_block *sb,
2727 				 ext4_group_t group, int barrier);
2728 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2729 
2730 /* fast_commit.c */
2731 int ext4_fc_info_show(struct seq_file *seq, void *v);
2732 void ext4_fc_init(struct super_block *sb, journal_t *journal);
2733 void ext4_fc_init_inode(struct inode *inode);
2734 void ext4_fc_track_range(struct inode *inode, ext4_lblk_t start,
2735 			 ext4_lblk_t end);
2736 void ext4_fc_track_unlink(struct inode *inode, struct dentry *dentry);
2737 void ext4_fc_track_link(struct inode *inode, struct dentry *dentry);
2738 void ext4_fc_track_create(struct inode *inode, struct dentry *dentry);
2739 void ext4_fc_track_inode(struct inode *inode);
2740 void ext4_fc_mark_ineligible(struct super_block *sb, int reason);
2741 void ext4_fc_start_ineligible(struct super_block *sb, int reason);
2742 void ext4_fc_stop_ineligible(struct super_block *sb);
2743 void ext4_fc_start_update(struct inode *inode);
2744 void ext4_fc_stop_update(struct inode *inode);
2745 void ext4_fc_del(struct inode *inode);
2746 bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block);
2747 void ext4_fc_replay_cleanup(struct super_block *sb);
2748 int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
2749 int __init ext4_fc_init_dentry_cache(void);
2750 
2751 /* mballoc.c */
2752 extern const struct seq_operations ext4_mb_seq_groups_ops;
2753 extern long ext4_mb_stats;
2754 extern long ext4_mb_max_to_scan;
2755 extern int ext4_mb_init(struct super_block *);
2756 extern int ext4_mb_release(struct super_block *);
2757 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2758 				struct ext4_allocation_request *, int *);
2759 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2760 extern void ext4_discard_preallocations(struct inode *, unsigned int);
2761 extern int __init ext4_init_mballoc(void);
2762 extern void ext4_exit_mballoc(void);
2763 extern ext4_group_t ext4_mb_prefetch(struct super_block *sb,
2764 				     ext4_group_t group,
2765 				     unsigned int nr, int *cnt);
2766 extern void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group,
2767 				  unsigned int nr);
2768 
2769 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2770 			     struct buffer_head *bh, ext4_fsblk_t block,
2771 			     unsigned long count, int flags);
2772 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2773 				   ext4_group_t ngroups);
2774 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2775 		ext4_group_t i, struct ext4_group_desc *desc);
2776 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2777 				ext4_fsblk_t block, unsigned long count);
2778 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2779 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2780 extern void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block,
2781 		       int len, int state);
2782 
2783 /* inode.c */
2784 void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
2785 			 struct ext4_inode_info *ei);
2786 int ext4_inode_is_fast_symlink(struct inode *inode);
2787 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2788 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2789 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2790 		     bool wait, struct buffer_head **bhs);
2791 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2792 			     struct buffer_head *bh_result, int create);
2793 int ext4_get_block(struct inode *inode, sector_t iblock,
2794 		   struct buffer_head *bh_result, int create);
2795 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2796 			   struct buffer_head *bh, int create);
2797 int ext4_walk_page_buffers(handle_t *handle,
2798 			   struct buffer_head *head,
2799 			   unsigned from,
2800 			   unsigned to,
2801 			   int *partial,
2802 			   int (*fn)(handle_t *handle,
2803 				     struct buffer_head *bh));
2804 int do_journal_get_write_access(handle_t *handle,
2805 				struct buffer_head *bh);
2806 #define FALL_BACK_TO_NONDELALLOC 1
2807 #define CONVERT_INLINE_DATA	 2
2808 
2809 typedef enum {
2810 	EXT4_IGET_NORMAL =	0,
2811 	EXT4_IGET_SPECIAL =	0x0001, /* OK to iget a system inode */
2812 	EXT4_IGET_HANDLE = 	0x0002	/* Inode # is from a handle */
2813 } ext4_iget_flags;
2814 
2815 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2816 				 ext4_iget_flags flags, const char *function,
2817 				 unsigned int line);
2818 
2819 #define ext4_iget(sb, ino, flags) \
2820 	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2821 
2822 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2823 extern int  ext4_setattr(struct dentry *, struct iattr *);
2824 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2825 extern void ext4_evict_inode(struct inode *);
2826 extern void ext4_clear_inode(struct inode *);
2827 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2828 extern int  ext4_sync_inode(handle_t *, struct inode *);
2829 extern void ext4_dirty_inode(struct inode *, int);
2830 extern int ext4_change_inode_journal_flag(struct inode *, int);
2831 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2832 extern int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino,
2833 			  struct ext4_iloc *iloc);
2834 extern int ext4_inode_attach_jinode(struct inode *inode);
2835 extern int ext4_can_truncate(struct inode *inode);
2836 extern int ext4_truncate(struct inode *);
2837 extern int ext4_break_layouts(struct inode *);
2838 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2839 extern void ext4_set_inode_flags(struct inode *, bool init);
2840 extern int ext4_alloc_da_blocks(struct inode *inode);
2841 extern void ext4_set_aops(struct inode *inode);
2842 extern int ext4_writepage_trans_blocks(struct inode *);
2843 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2844 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2845 			     loff_t lstart, loff_t lend);
2846 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
2847 extern vm_fault_t ext4_filemap_fault(struct vm_fault *vmf);
2848 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2849 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2850 extern void ext4_da_release_space(struct inode *inode, int to_free);
2851 extern void ext4_da_update_reserve_space(struct inode *inode,
2852 					int used, int quota_claim);
2853 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2854 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2855 
2856 /* indirect.c */
2857 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2858 				struct ext4_map_blocks *map, int flags);
2859 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2860 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2861 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2862 				 ext4_lblk_t start, ext4_lblk_t end);
2863 
2864 /* ioctl.c */
2865 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2866 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2867 extern void ext4_reset_inode_seed(struct inode *inode);
2868 
2869 /* migrate.c */
2870 extern int ext4_ext_migrate(struct inode *);
2871 extern int ext4_ind_migrate(struct inode *inode);
2872 
2873 /* namei.c */
2874 extern int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2875 			     struct inode *inode);
2876 extern int ext4_dirblock_csum_verify(struct inode *inode,
2877 				     struct buffer_head *bh);
2878 extern int ext4_orphan_add(handle_t *, struct inode *);
2879 extern int ext4_orphan_del(handle_t *, struct inode *);
2880 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2881 				__u32 start_minor_hash, __u32 *next_hash);
2882 extern int ext4_search_dir(struct buffer_head *bh,
2883 			   char *search_buf,
2884 			   int buf_size,
2885 			   struct inode *dir,
2886 			   struct ext4_filename *fname,
2887 			   unsigned int offset,
2888 			   struct ext4_dir_entry_2 **res_dir);
2889 extern int ext4_generic_delete_entry(struct inode *dir,
2890 				     struct ext4_dir_entry_2 *de_del,
2891 				     struct buffer_head *bh,
2892 				     void *entry_buf,
2893 				     int buf_size,
2894 				     int csum_size);
2895 extern bool ext4_empty_dir(struct inode *inode);
2896 
2897 /* resize.c */
2898 extern void ext4_kvfree_array_rcu(void *to_free);
2899 extern int ext4_group_add(struct super_block *sb,
2900 				struct ext4_new_group_data *input);
2901 extern int ext4_group_extend(struct super_block *sb,
2902 				struct ext4_super_block *es,
2903 				ext4_fsblk_t n_blocks_count);
2904 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2905 
2906 /* super.c */
2907 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
2908 					 sector_t block, int op_flags);
2909 extern struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
2910 						   sector_t block);
2911 extern void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
2912 				bh_end_io_t *end_io);
2913 extern int ext4_read_bh(struct buffer_head *bh, int op_flags,
2914 			bh_end_io_t *end_io);
2915 extern int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait);
2916 extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
2917 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2918 extern int ext4_calculate_overhead(struct super_block *sb);
2919 extern void ext4_superblock_csum_set(struct super_block *sb);
2920 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2921 				    ext4_group_t ngroup);
2922 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2923 				     char nbuf[16]);
2924 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
2925 					     ext4_group_t block_group,
2926 					     unsigned int flags);
2927 
2928 extern __printf(6, 7)
2929 void __ext4_error(struct super_block *, const char *, unsigned int, int, __u64,
2930 		  const char *, ...);
2931 extern __printf(6, 7)
2932 void __ext4_error_inode(struct inode *, const char *, unsigned int,
2933 			ext4_fsblk_t, int, const char *, ...);
2934 extern __printf(5, 6)
2935 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2936 		     const char *, ...);
2937 extern void __ext4_std_error(struct super_block *, const char *,
2938 			     unsigned int, int);
2939 extern __printf(5, 6)
2940 void __ext4_abort(struct super_block *, const char *, unsigned int, int,
2941 		  const char *, ...);
2942 extern __printf(4, 5)
2943 void __ext4_warning(struct super_block *, const char *, unsigned int,
2944 		    const char *, ...);
2945 extern __printf(4, 5)
2946 void __ext4_warning_inode(const struct inode *inode, const char *function,
2947 			  unsigned int line, const char *fmt, ...);
2948 extern __printf(3, 4)
2949 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2950 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2951 			   const char *, unsigned int, const char *);
2952 extern __printf(7, 8)
2953 void __ext4_grp_locked_error(const char *, unsigned int,
2954 			     struct super_block *, ext4_group_t,
2955 			     unsigned long, ext4_fsblk_t,
2956 			     const char *, ...);
2957 
2958 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2959 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2960 
2961 #define EXT4_ERROR_INODE_ERR(inode, err, fmt, a...)			\
2962 	__ext4_error_inode((inode), __func__, __LINE__, 0, (err), (fmt), ## a)
2963 
2964 #define ext4_error_inode_block(inode, block, err, fmt, a...)		\
2965 	__ext4_error_inode((inode), __func__, __LINE__, (block), (err),	\
2966 			   (fmt), ## a)
2967 
2968 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2969 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2970 
2971 #ifdef CONFIG_PRINTK
2972 
2973 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2974 	__ext4_error_inode(inode, func, line, block, 0, fmt, ##__VA_ARGS__)
2975 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
2976 	__ext4_error_inode((inode), (func), (line), (block), 		\
2977 			   (err), (fmt), ##__VA_ARGS__)
2978 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2979 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2980 #define ext4_error(sb, fmt, ...)					\
2981 	__ext4_error((sb), __func__, __LINE__, 0, 0, (fmt), ##__VA_ARGS__)
2982 #define ext4_error_err(sb, err, fmt, ...)				\
2983 	__ext4_error((sb), __func__, __LINE__, (err), 0, (fmt), ##__VA_ARGS__)
2984 #define ext4_abort(sb, err, fmt, ...)					\
2985 	__ext4_abort((sb), __func__, __LINE__, (err), (fmt), ##__VA_ARGS__)
2986 #define ext4_warning(sb, fmt, ...)					\
2987 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2988 #define ext4_warning_inode(inode, fmt, ...)				\
2989 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2990 #define ext4_msg(sb, level, fmt, ...)				\
2991 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2992 #define dump_mmp_msg(sb, mmp, msg)					\
2993 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2994 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2995 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2996 				fmt, ##__VA_ARGS__)
2997 
2998 #else
2999 
3000 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
3001 do {									\
3002 	no_printk(fmt, ##__VA_ARGS__);					\
3003 	__ext4_error_inode(inode, "", 0, block, 0, " ");		\
3004 } while (0)
3005 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
3006 do {									\
3007 	no_printk(fmt, ##__VA_ARGS__);					\
3008 	__ext4_error_inode(inode, "", 0, block, err, " ");		\
3009 } while (0)
3010 #define ext4_error_file(file, func, line, block, fmt, ...)		\
3011 do {									\
3012 	no_printk(fmt, ##__VA_ARGS__);					\
3013 	__ext4_error_file(file, "", 0, block, " ");			\
3014 } while (0)
3015 #define ext4_error(sb, fmt, ...)					\
3016 do {									\
3017 	no_printk(fmt, ##__VA_ARGS__);					\
3018 	__ext4_error(sb, "", 0, 0, 0, " ");				\
3019 } while (0)
3020 #define ext4_error_err(sb, err, fmt, ...)				\
3021 do {									\
3022 	no_printk(fmt, ##__VA_ARGS__);					\
3023 	__ext4_error(sb, "", 0, err, 0, " ");				\
3024 } while (0)
3025 #define ext4_abort(sb, err, fmt, ...)					\
3026 do {									\
3027 	no_printk(fmt, ##__VA_ARGS__);					\
3028 	__ext4_abort(sb, "", 0, err, " ");				\
3029 } while (0)
3030 #define ext4_warning(sb, fmt, ...)					\
3031 do {									\
3032 	no_printk(fmt, ##__VA_ARGS__);					\
3033 	__ext4_warning(sb, "", 0, " ");					\
3034 } while (0)
3035 #define ext4_warning_inode(inode, fmt, ...)				\
3036 do {									\
3037 	no_printk(fmt, ##__VA_ARGS__);					\
3038 	__ext4_warning_inode(inode, "", 0, " ");			\
3039 } while (0)
3040 #define ext4_msg(sb, level, fmt, ...)					\
3041 do {									\
3042 	no_printk(fmt, ##__VA_ARGS__);					\
3043 	__ext4_msg(sb, "", " ");					\
3044 } while (0)
3045 #define dump_mmp_msg(sb, mmp, msg)					\
3046 	__dump_mmp_msg(sb, mmp, "", 0, "")
3047 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
3048 do {									\
3049 	no_printk(fmt, ##__VA_ARGS__);				\
3050 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
3051 } while (0)
3052 
3053 #endif
3054 
3055 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
3056 				      struct ext4_group_desc *bg);
3057 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
3058 				      struct ext4_group_desc *bg);
3059 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
3060 				     struct ext4_group_desc *bg);
3061 extern __u32 ext4_free_group_clusters(struct super_block *sb,
3062 				      struct ext4_group_desc *bg);
3063 extern __u32 ext4_free_inodes_count(struct super_block *sb,
3064 				 struct ext4_group_desc *bg);
3065 extern __u32 ext4_used_dirs_count(struct super_block *sb,
3066 				struct ext4_group_desc *bg);
3067 extern __u32 ext4_itable_unused_count(struct super_block *sb,
3068 				   struct ext4_group_desc *bg);
3069 extern void ext4_block_bitmap_set(struct super_block *sb,
3070 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3071 extern void ext4_inode_bitmap_set(struct super_block *sb,
3072 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3073 extern void ext4_inode_table_set(struct super_block *sb,
3074 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
3075 extern void ext4_free_group_clusters_set(struct super_block *sb,
3076 					 struct ext4_group_desc *bg,
3077 					 __u32 count);
3078 extern void ext4_free_inodes_set(struct super_block *sb,
3079 				struct ext4_group_desc *bg, __u32 count);
3080 extern void ext4_used_dirs_set(struct super_block *sb,
3081 				struct ext4_group_desc *bg, __u32 count);
3082 extern void ext4_itable_unused_set(struct super_block *sb,
3083 				   struct ext4_group_desc *bg, __u32 count);
3084 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
3085 				       struct ext4_group_desc *gdp);
3086 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
3087 				     struct ext4_group_desc *gdp);
3088 extern int ext4_register_li_request(struct super_block *sb,
3089 				    ext4_group_t first_not_zeroed);
3090 
3091 static inline int ext4_has_metadata_csum(struct super_block *sb)
3092 {
3093 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
3094 		     !EXT4_SB(sb)->s_chksum_driver);
3095 
3096 	return ext4_has_feature_metadata_csum(sb) &&
3097 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
3098 }
3099 
3100 static inline int ext4_has_group_desc_csum(struct super_block *sb)
3101 {
3102 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
3103 }
3104 
3105 #define ext4_read_incompat_64bit_val(es, name) \
3106 	(((es)->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT) \
3107 		? (ext4_fsblk_t)le32_to_cpu(es->name##_hi) << 32 : 0) | \
3108 		le32_to_cpu(es->name##_lo))
3109 
3110 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
3111 {
3112 	return ext4_read_incompat_64bit_val(es, s_blocks_count);
3113 }
3114 
3115 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
3116 {
3117 	return ext4_read_incompat_64bit_val(es, s_r_blocks_count);
3118 }
3119 
3120 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
3121 {
3122 	return ext4_read_incompat_64bit_val(es, s_free_blocks_count);
3123 }
3124 
3125 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
3126 					 ext4_fsblk_t blk)
3127 {
3128 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
3129 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
3130 }
3131 
3132 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
3133 					      ext4_fsblk_t blk)
3134 {
3135 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
3136 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
3137 }
3138 
3139 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
3140 					   ext4_fsblk_t blk)
3141 {
3142 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
3143 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
3144 }
3145 
3146 static inline loff_t ext4_isize(struct super_block *sb,
3147 				struct ext4_inode *raw_inode)
3148 {
3149 	if (ext4_has_feature_largedir(sb) ||
3150 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
3151 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
3152 			le32_to_cpu(raw_inode->i_size_lo);
3153 
3154 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
3155 }
3156 
3157 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
3158 {
3159 	raw_inode->i_size_lo = cpu_to_le32(i_size);
3160 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
3161 }
3162 
3163 static inline
3164 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
3165 					    ext4_group_t group)
3166 {
3167 	 struct ext4_group_info **grp_info;
3168 	 long indexv, indexh;
3169 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
3170 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
3171 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
3172 	 grp_info = sbi_array_rcu_deref(EXT4_SB(sb), s_group_info, indexv);
3173 	 return grp_info[indexh];
3174 }
3175 
3176 /*
3177  * Reading s_groups_count requires using smp_rmb() afterwards.  See
3178  * the locking protocol documented in the comments of ext4_group_add()
3179  * in resize.c
3180  */
3181 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
3182 {
3183 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
3184 
3185 	smp_rmb();
3186 	return ngroups;
3187 }
3188 
3189 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
3190 					     ext4_group_t block_group)
3191 {
3192 	return block_group >> sbi->s_log_groups_per_flex;
3193 }
3194 
3195 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
3196 {
3197 	return 1 << sbi->s_log_groups_per_flex;
3198 }
3199 
3200 #define ext4_std_error(sb, errno)				\
3201 do {								\
3202 	if ((errno))						\
3203 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
3204 } while (0)
3205 
3206 #ifdef CONFIG_SMP
3207 /* Each CPU can accumulate percpu_counter_batch clusters in their local
3208  * counters. So we need to make sure we have free clusters more
3209  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
3210  */
3211 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
3212 #else
3213 #define EXT4_FREECLUSTERS_WATERMARK 0
3214 #endif
3215 
3216 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
3217 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
3218 {
3219 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
3220 		     !inode_is_locked(inode));
3221 	down_write(&EXT4_I(inode)->i_data_sem);
3222 	if (newsize > EXT4_I(inode)->i_disksize)
3223 		WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
3224 	up_write(&EXT4_I(inode)->i_data_sem);
3225 }
3226 
3227 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
3228 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
3229 {
3230 	int changed = 0;
3231 
3232 	if (newsize > inode->i_size) {
3233 		i_size_write(inode, newsize);
3234 		changed = 1;
3235 	}
3236 	if (newsize > EXT4_I(inode)->i_disksize) {
3237 		ext4_update_i_disksize(inode, newsize);
3238 		changed |= 2;
3239 	}
3240 	return changed;
3241 }
3242 
3243 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
3244 				      loff_t len);
3245 
3246 struct ext4_group_info {
3247 	unsigned long   bb_state;
3248 #ifdef AGGRESSIVE_CHECK
3249 	unsigned long	bb_check_counter;
3250 #endif
3251 	struct rb_root  bb_free_root;
3252 	ext4_grpblk_t	bb_first_free;	/* first free block */
3253 	ext4_grpblk_t	bb_free;	/* total free blocks */
3254 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
3255 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
3256 	struct          list_head bb_prealloc_list;
3257 #ifdef DOUBLE_CHECK
3258 	void            *bb_bitmap;
3259 #endif
3260 	struct rw_semaphore alloc_sem;
3261 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
3262 					 * regions, index is order.
3263 					 * bb_counters[3] = 5 means
3264 					 * 5 free 8-block regions. */
3265 };
3266 
3267 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
3268 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
3269 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
3270 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
3271 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT		\
3272 	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
3273 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT		\
3274 	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
3275 #define EXT4_GROUP_INFO_BBITMAP_READ_BIT	4
3276 
3277 #define EXT4_MB_GRP_NEED_INIT(grp)	\
3278 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
3279 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
3280 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3281 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
3282 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3283 
3284 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
3285 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3286 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
3287 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3288 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
3289 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3290 #define EXT4_MB_GRP_TEST_AND_SET_READ(grp)	\
3291 	(test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_READ_BIT, &((grp)->bb_state)))
3292 
3293 #define EXT4_MAX_CONTENTION		8
3294 #define EXT4_CONTENTION_THRESHOLD	2
3295 
3296 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
3297 					      ext4_group_t group)
3298 {
3299 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
3300 }
3301 
3302 /*
3303  * Returns true if the filesystem is busy enough that attempts to
3304  * access the block group locks has run into contention.
3305  */
3306 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
3307 {
3308 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
3309 }
3310 
3311 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
3312 {
3313 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
3314 	if (spin_trylock(lock))
3315 		/*
3316 		 * We're able to grab the lock right away, so drop the
3317 		 * lock contention counter.
3318 		 */
3319 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
3320 	else {
3321 		/*
3322 		 * The lock is busy, so bump the contention counter,
3323 		 * and then wait on the spin lock.
3324 		 */
3325 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
3326 				  EXT4_MAX_CONTENTION);
3327 		spin_lock(lock);
3328 	}
3329 }
3330 
3331 static inline void ext4_unlock_group(struct super_block *sb,
3332 					ext4_group_t group)
3333 {
3334 	spin_unlock(ext4_group_lock_ptr(sb, group));
3335 }
3336 
3337 /*
3338  * Block validity checking
3339  */
3340 #define ext4_check_indirect_blockref(inode, bh)				\
3341 	ext4_check_blockref(__func__, __LINE__, inode,			\
3342 			    (__le32 *)(bh)->b_data,			\
3343 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3344 
3345 #define ext4_ind_check_inode(inode)					\
3346 	ext4_check_blockref(__func__, __LINE__, inode,			\
3347 			    EXT4_I(inode)->i_data,			\
3348 			    EXT4_NDIR_BLOCKS)
3349 
3350 /*
3351  * Inodes and files operations
3352  */
3353 
3354 /* dir.c */
3355 extern const struct file_operations ext4_dir_operations;
3356 
3357 #ifdef CONFIG_UNICODE
3358 extern const struct dentry_operations ext4_dentry_ops;
3359 #endif
3360 
3361 /* file.c */
3362 extern const struct inode_operations ext4_file_inode_operations;
3363 extern const struct file_operations ext4_file_operations;
3364 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
3365 
3366 /* inline.c */
3367 extern int ext4_get_max_inline_size(struct inode *inode);
3368 extern int ext4_find_inline_data_nolock(struct inode *inode);
3369 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
3370 				 unsigned int len);
3371 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3372 
3373 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
3374 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3375 					 struct inode *inode,
3376 					 loff_t pos, unsigned len,
3377 					 unsigned flags,
3378 					 struct page **pagep);
3379 extern int ext4_write_inline_data_end(struct inode *inode,
3380 				      loff_t pos, unsigned len,
3381 				      unsigned copied,
3382 				      struct page *page);
3383 extern struct buffer_head *
3384 ext4_journalled_write_inline_data(struct inode *inode,
3385 				  unsigned len,
3386 				  struct page *page);
3387 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3388 					   struct inode *inode,
3389 					   loff_t pos, unsigned len,
3390 					   unsigned flags,
3391 					   struct page **pagep,
3392 					   void **fsdata);
3393 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3394 					 unsigned len, unsigned copied,
3395 					 struct page *page);
3396 extern int ext4_try_add_inline_entry(handle_t *handle,
3397 				     struct ext4_filename *fname,
3398 				     struct inode *dir, struct inode *inode);
3399 extern int ext4_try_create_inline_dir(handle_t *handle,
3400 				      struct inode *parent,
3401 				      struct inode *inode);
3402 extern int ext4_read_inline_dir(struct file *filp,
3403 				struct dir_context *ctx,
3404 				int *has_inline_data);
3405 extern int ext4_inlinedir_to_tree(struct file *dir_file,
3406 				  struct inode *dir, ext4_lblk_t block,
3407 				  struct dx_hash_info *hinfo,
3408 				  __u32 start_hash, __u32 start_minor_hash,
3409 				  int *has_inline_data);
3410 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3411 					struct ext4_filename *fname,
3412 					struct ext4_dir_entry_2 **res_dir,
3413 					int *has_inline_data);
3414 extern int ext4_delete_inline_entry(handle_t *handle,
3415 				    struct inode *dir,
3416 				    struct ext4_dir_entry_2 *de_del,
3417 				    struct buffer_head *bh,
3418 				    int *has_inline_data);
3419 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3420 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3421 					struct ext4_dir_entry_2 **parent_de,
3422 					int *retval);
3423 extern int ext4_inline_data_fiemap(struct inode *inode,
3424 				   struct fiemap_extent_info *fieinfo,
3425 				   int *has_inline, __u64 start, __u64 len);
3426 
3427 struct iomap;
3428 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3429 
3430 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3431 
3432 extern int ext4_convert_inline_data(struct inode *inode);
3433 
3434 static inline int ext4_has_inline_data(struct inode *inode)
3435 {
3436 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3437 	       EXT4_I(inode)->i_inline_off;
3438 }
3439 
3440 /* namei.c */
3441 extern const struct inode_operations ext4_dir_inode_operations;
3442 extern const struct inode_operations ext4_special_inode_operations;
3443 extern struct dentry *ext4_get_parent(struct dentry *child);
3444 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3445 				 struct ext4_dir_entry_2 *de,
3446 				 int blocksize, int csum_size,
3447 				 unsigned int parent_ino, int dotdot_real_len);
3448 extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
3449 					unsigned int blocksize);
3450 extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
3451 				      struct buffer_head *bh);
3452 extern int ext4_ci_compare(const struct inode *parent,
3453 			   const struct qstr *fname,
3454 			   const struct qstr *entry, bool quick);
3455 extern int __ext4_unlink(struct inode *dir, const struct qstr *d_name,
3456 			 struct inode *inode);
3457 extern int __ext4_link(struct inode *dir, struct inode *inode,
3458 		       struct dentry *dentry);
3459 
3460 #define S_SHIFT 12
3461 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3462 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3463 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3464 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3465 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3466 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3467 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3468 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3469 };
3470 
3471 static inline void ext4_set_de_type(struct super_block *sb,
3472 				struct ext4_dir_entry_2 *de,
3473 				umode_t mode) {
3474 	if (ext4_has_feature_filetype(sb))
3475 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3476 }
3477 
3478 /* readpages.c */
3479 extern int ext4_mpage_readpages(struct inode *inode,
3480 		struct readahead_control *rac, struct page *page);
3481 extern int __init ext4_init_post_read_processing(void);
3482 extern void ext4_exit_post_read_processing(void);
3483 
3484 /* symlink.c */
3485 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3486 extern const struct inode_operations ext4_symlink_inode_operations;
3487 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3488 
3489 /* sysfs.c */
3490 extern int ext4_register_sysfs(struct super_block *sb);
3491 extern void ext4_unregister_sysfs(struct super_block *sb);
3492 extern int __init ext4_init_sysfs(void);
3493 extern void ext4_exit_sysfs(void);
3494 
3495 /* block_validity */
3496 extern void ext4_release_system_zone(struct super_block *sb);
3497 extern int ext4_setup_system_zone(struct super_block *sb);
3498 extern int __init ext4_init_system_zone(void);
3499 extern void ext4_exit_system_zone(void);
3500 extern int ext4_inode_block_valid(struct inode *inode,
3501 				  ext4_fsblk_t start_blk,
3502 				  unsigned int count);
3503 extern int ext4_check_blockref(const char *, unsigned int,
3504 			       struct inode *, __le32 *, unsigned int);
3505 
3506 /* extents.c */
3507 struct ext4_ext_path;
3508 struct ext4_extent;
3509 
3510 /*
3511  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3512  * __le32.
3513  */
3514 #define EXT_MAX_BLOCKS	0xffffffff
3515 
3516 extern void ext4_ext_tree_init(handle_t *handle, struct inode *inode);
3517 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3518 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3519 			       struct ext4_map_blocks *map, int flags);
3520 extern int ext4_ext_truncate(handle_t *, struct inode *);
3521 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3522 				 ext4_lblk_t end);
3523 extern void ext4_ext_init(struct super_block *);
3524 extern void ext4_ext_release(struct super_block *);
3525 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3526 			  loff_t len);
3527 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3528 					  loff_t offset, ssize_t len);
3529 extern int ext4_convert_unwritten_io_end_vec(handle_t *handle,
3530 					     ext4_io_end_t *io_end);
3531 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3532 			   struct ext4_map_blocks *map, int flags);
3533 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3534 						   int num,
3535 						   struct ext4_ext_path *path);
3536 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3537 				  struct ext4_ext_path **,
3538 				  struct ext4_extent *, int);
3539 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3540 					      struct ext4_ext_path **,
3541 					      int flags);
3542 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3543 extern int ext4_ext_check_inode(struct inode *inode);
3544 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3545 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3546 			__u64 start, __u64 len);
3547 extern int ext4_get_es_cache(struct inode *inode,
3548 			     struct fiemap_extent_info *fieinfo,
3549 			     __u64 start, __u64 len);
3550 extern int ext4_ext_precache(struct inode *inode);
3551 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3552 				struct inode *inode2, ext4_lblk_t lblk1,
3553 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3554 			     int mark_unwritten,int *err);
3555 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3556 extern int ext4_datasem_ensure_credits(handle_t *handle, struct inode *inode,
3557 				       int check_cred, int restart_cred,
3558 				       int revoke_cred);
3559 extern void ext4_ext_replay_shrink_inode(struct inode *inode, ext4_lblk_t end);
3560 extern int ext4_ext_replay_set_iblocks(struct inode *inode);
3561 extern int ext4_ext_replay_update_ex(struct inode *inode, ext4_lblk_t start,
3562 		int len, int unwritten, ext4_fsblk_t pblk);
3563 extern int ext4_ext_clear_bb(struct inode *inode);
3564 
3565 
3566 /* move_extent.c */
3567 extern void ext4_double_down_write_data_sem(struct inode *first,
3568 					    struct inode *second);
3569 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3570 					  struct inode *donor_inode);
3571 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3572 			     __u64 start_orig, __u64 start_donor,
3573 			     __u64 len, __u64 *moved_len);
3574 
3575 /* page-io.c */
3576 extern int __init ext4_init_pageio(void);
3577 extern void ext4_exit_pageio(void);
3578 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3579 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3580 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3581 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3582 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3583 				struct writeback_control *wbc);
3584 extern void ext4_end_io_rsv_work(struct work_struct *work);
3585 extern void ext4_io_submit(struct ext4_io_submit *io);
3586 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3587 			       struct page *page,
3588 			       int len,
3589 			       struct writeback_control *wbc,
3590 			       bool keep_towrite);
3591 extern struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end);
3592 extern struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end);
3593 
3594 /* mmp.c */
3595 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3596 
3597 /* verity.c */
3598 extern const struct fsverity_operations ext4_verityops;
3599 
3600 /*
3601  * Add new method to test whether block and inode bitmaps are properly
3602  * initialized. With uninit_bg reading the block from disk is not enough
3603  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3604  */
3605 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3606 
3607 static inline int bitmap_uptodate(struct buffer_head *bh)
3608 {
3609 	return (buffer_uptodate(bh) &&
3610 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3611 }
3612 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3613 {
3614 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3615 }
3616 
3617 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3618 
3619 /* For ioend & aio unwritten conversion wait queues */
3620 #define EXT4_WQ_HASH_SZ		37
3621 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3622 					    EXT4_WQ_HASH_SZ])
3623 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3624 
3625 extern int ext4_resize_begin(struct super_block *sb);
3626 extern void ext4_resize_end(struct super_block *sb);
3627 
3628 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3629 					      struct ext4_io_end *io_end)
3630 {
3631 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3632 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3633 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3634 	}
3635 }
3636 
3637 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3638 {
3639 	struct inode *inode = io_end->inode;
3640 
3641 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3642 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3643 		/* Wake up anyone waiting on unwritten extent conversion */
3644 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3645 			wake_up_all(ext4_ioend_wq(inode));
3646 	}
3647 }
3648 
3649 extern const struct iomap_ops ext4_iomap_ops;
3650 extern const struct iomap_ops ext4_iomap_overwrite_ops;
3651 extern const struct iomap_ops ext4_iomap_report_ops;
3652 
3653 static inline int ext4_buffer_uptodate(struct buffer_head *bh)
3654 {
3655 	/*
3656 	 * If the buffer has the write error flag, we have failed
3657 	 * to write out data in the block.  In this  case, we don't
3658 	 * have to read the block because we may read the old data
3659 	 * successfully.
3660 	 */
3661 	if (!buffer_uptodate(bh) && buffer_write_io_error(bh))
3662 		set_buffer_uptodate(bh);
3663 	return buffer_uptodate(bh);
3664 }
3665 
3666 #endif	/* __KERNEL__ */
3667 
3668 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3669 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3670 
3671 #endif	/* _EXT4_H */
3672