xref: /linux/fs/ext4/ext4.h (revision 4cf1bc1f10452065a29d576fc5693fc4fab5b919)
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_INELIGIBLE		0x0008	/* Fast commit ineligible */
1170 #define EXT4_FC_COMMITTING		0x0010	/* File system underoing a fast
1171 						 * commit.
1172 						 */
1173 #define EXT4_FC_REPLAY			0x0020	/* Fast commit replay ongoing */
1174 
1175 /*
1176  * Misc. filesystem flags
1177  */
1178 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1179 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1180 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1181 
1182 /*
1183  * Mount flags set via mount options or defaults
1184  */
1185 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1186 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1187 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1188 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1189 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1190 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1191 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1192 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1193 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1194 #ifdef CONFIG_FS_DAX
1195 #define EXT4_MOUNT_DAX_ALWAYS		0x00200	/* Direct Access */
1196 #else
1197 #define EXT4_MOUNT_DAX_ALWAYS		0
1198 #endif
1199 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1200 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1201 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1202 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1203 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1204 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1205 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1206 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1207 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1208 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1209 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1210 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1211 						 * enable enforcement for hidden
1212 						 * quota files */
1213 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1214 						  * enforcement for hidden quota
1215 						  * files */
1216 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1217 						  * enforcement */
1218 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1219 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1220 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1221 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
1222 #define EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS 0x4000000
1223 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1224 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1225 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1226 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1227 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1228 
1229 /*
1230  * Mount flags set either automatically (could not be set by mount option)
1231  * based on per file system feature or property or in special cases such as
1232  * distinguishing between explicit mount option definition and default.
1233  */
1234 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1235 						      specified delalloc */
1236 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1237 						      size of blocksize * 8
1238 						      blocks */
1239 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1240 						      file systems */
1241 #define EXT4_MOUNT2_DAX_NEVER		0x00000008 /* Do not allow Direct Access */
1242 #define EXT4_MOUNT2_DAX_INODE		0x00000010 /* For printing options only */
1243 
1244 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1245 						specified journal checksum */
1246 
1247 #define EXT4_MOUNT2_JOURNAL_FAST_COMMIT	0x00000010 /* Journal fast commit */
1248 
1249 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1250 						~EXT4_MOUNT_##opt
1251 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1252 						EXT4_MOUNT_##opt
1253 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1254 					 EXT4_MOUNT_##opt)
1255 
1256 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1257 						~EXT4_MOUNT2_##opt
1258 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1259 						EXT4_MOUNT2_##opt
1260 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1261 					 EXT4_MOUNT2_##opt)
1262 
1263 #define ext4_test_and_set_bit		__test_and_set_bit_le
1264 #define ext4_set_bit			__set_bit_le
1265 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1266 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1267 #define ext4_clear_bit			__clear_bit_le
1268 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1269 #define ext4_test_bit			test_bit_le
1270 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1271 #define ext4_find_next_bit		find_next_bit_le
1272 
1273 extern void ext4_set_bits(void *bm, int cur, int len);
1274 
1275 /*
1276  * Maximal mount counts between two filesystem checks
1277  */
1278 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1279 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1280 
1281 /*
1282  * Behaviour when detecting errors
1283  */
1284 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1285 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1286 #define EXT4_ERRORS_PANIC		3	/* Panic */
1287 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1288 
1289 /* Metadata checksum algorithm codes */
1290 #define EXT4_CRC32C_CHKSUM		1
1291 
1292 /*
1293  * Structure of the super block
1294  */
1295 struct ext4_super_block {
1296 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1297 	__le32	s_blocks_count_lo;	/* Blocks count */
1298 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1299 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1300 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1301 	__le32	s_first_data_block;	/* First Data Block */
1302 	__le32	s_log_block_size;	/* Block size */
1303 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1304 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1305 	__le32	s_clusters_per_group;	/* # Clusters per group */
1306 	__le32	s_inodes_per_group;	/* # Inodes per group */
1307 	__le32	s_mtime;		/* Mount time */
1308 /*30*/	__le32	s_wtime;		/* Write time */
1309 	__le16	s_mnt_count;		/* Mount count */
1310 	__le16	s_max_mnt_count;	/* Maximal mount count */
1311 	__le16	s_magic;		/* Magic signature */
1312 	__le16	s_state;		/* File system state */
1313 	__le16	s_errors;		/* Behaviour when detecting errors */
1314 	__le16	s_minor_rev_level;	/* minor revision level */
1315 /*40*/	__le32	s_lastcheck;		/* time of last check */
1316 	__le32	s_checkinterval;	/* max. time between checks */
1317 	__le32	s_creator_os;		/* OS */
1318 	__le32	s_rev_level;		/* Revision level */
1319 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1320 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1321 	/*
1322 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1323 	 *
1324 	 * Note: the difference between the compatible feature set and
1325 	 * the incompatible feature set is that if there is a bit set
1326 	 * in the incompatible feature set that the kernel doesn't
1327 	 * know about, it should refuse to mount the filesystem.
1328 	 *
1329 	 * e2fsck's requirements are more strict; if it doesn't know
1330 	 * about a feature in either the compatible or incompatible
1331 	 * feature set, it must abort and not try to meddle with
1332 	 * things it doesn't understand...
1333 	 */
1334 	__le32	s_first_ino;		/* First non-reserved inode */
1335 	__le16  s_inode_size;		/* size of inode structure */
1336 	__le16	s_block_group_nr;	/* block group # of this superblock */
1337 	__le32	s_feature_compat;	/* compatible feature set */
1338 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1339 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1340 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1341 /*78*/	char	s_volume_name[16];	/* volume name */
1342 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
1343 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1344 	/*
1345 	 * Performance hints.  Directory preallocation should only
1346 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1347 	 */
1348 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1349 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1350 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1351 	/*
1352 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1353 	 */
1354 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1355 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1356 	__le32	s_journal_dev;		/* device number of journal file */
1357 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1358 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1359 	__u8	s_def_hash_version;	/* Default hash version to use */
1360 	__u8	s_jnl_backup_type;
1361 	__le16  s_desc_size;		/* size of group descriptor */
1362 /*100*/	__le32	s_default_mount_opts;
1363 	__le32	s_first_meta_bg;	/* First metablock block group */
1364 	__le32	s_mkfs_time;		/* When the filesystem was created */
1365 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1366 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1367 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1368 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1369 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1370 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1371 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1372 	__le32	s_flags;		/* Miscellaneous flags */
1373 	__le16  s_raid_stride;		/* RAID stride */
1374 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1375 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1376 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1377 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1378 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1379 	__u8	s_encryption_level;	/* versioning level for encryption */
1380 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1381 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1382 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1383 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1384 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1385 					      snapshot's future use */
1386 	__le32	s_snapshot_list;	/* inode number of the head of the
1387 					   on-disk snapshot list */
1388 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1389 	__le32	s_error_count;		/* number of fs errors */
1390 	__le32	s_first_error_time;	/* first time an error happened */
1391 	__le32	s_first_error_ino;	/* inode involved in first error */
1392 	__le64	s_first_error_block;	/* block involved of first error */
1393 	__u8	s_first_error_func[32] __nonstring;	/* function where the error happened */
1394 	__le32	s_first_error_line;	/* line number where error happened */
1395 	__le32	s_last_error_time;	/* most recent time of an error */
1396 	__le32	s_last_error_ino;	/* inode involved in last error */
1397 	__le32	s_last_error_line;	/* line number where error happened */
1398 	__le64	s_last_error_block;	/* block involved of last error */
1399 	__u8	s_last_error_func[32] __nonstring;	/* function where the error happened */
1400 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1401 	__u8	s_mount_opts[64];
1402 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1403 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1404 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1405 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1406 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1407 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1408 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1409 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1410 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1411 	__u8	s_wtime_hi;
1412 	__u8	s_mtime_hi;
1413 	__u8	s_mkfs_time_hi;
1414 	__u8	s_lastcheck_hi;
1415 	__u8	s_first_error_time_hi;
1416 	__u8	s_last_error_time_hi;
1417 	__u8	s_first_error_errcode;
1418 	__u8    s_last_error_errcode;
1419 	__le16  s_encoding;		/* Filename charset encoding */
1420 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
1421 	__le32	s_reserved[95];		/* Padding to the end of the block */
1422 	__le32	s_checksum;		/* crc32c(superblock) */
1423 };
1424 
1425 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1426 
1427 #ifdef __KERNEL__
1428 
1429 /*
1430  * run-time mount flags
1431  */
1432 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1433 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
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  * Flags for ext4_sb_info.s_encoding_flags.
1448  */
1449 #define EXT4_ENC_STRICT_MODE_FL	(1 << 0)
1450 
1451 #define ext4_has_strict_mode(sbi) \
1452 	(sbi->s_encoding_flags & EXT4_ENC_STRICT_MODE_FL)
1453 
1454 /*
1455  * fourth extended-fs super-block data in memory
1456  */
1457 struct ext4_sb_info {
1458 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1459 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1460 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1461 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1462 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1463 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1464 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1465 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1466 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1467 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1468 	unsigned long s_overhead;  /* # of fs overhead clusters */
1469 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1470 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1471 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1472 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1473 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1474 	struct buffer_head * __rcu *s_group_desc;
1475 	unsigned int s_mount_opt;
1476 	unsigned int s_mount_opt2;
1477 	unsigned int s_mount_flags;
1478 	unsigned int s_def_mount_opt;
1479 	ext4_fsblk_t s_sb_block;
1480 	atomic64_t s_resv_clusters;
1481 	kuid_t s_resuid;
1482 	kgid_t s_resgid;
1483 	unsigned short s_mount_state;
1484 	unsigned short s_pad;
1485 	int s_addr_per_block_bits;
1486 	int s_desc_per_block_bits;
1487 	int s_inode_size;
1488 	int s_first_ino;
1489 	unsigned int s_inode_readahead_blks;
1490 	unsigned int s_inode_goal;
1491 	u32 s_hash_seed[4];
1492 	int s_def_hash_version;
1493 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1494 	struct percpu_counter s_freeclusters_counter;
1495 	struct percpu_counter s_freeinodes_counter;
1496 	struct percpu_counter s_dirs_counter;
1497 	struct percpu_counter s_dirtyclusters_counter;
1498 	struct blockgroup_lock *s_blockgroup_lock;
1499 	struct proc_dir_entry *s_proc;
1500 	struct kobject s_kobj;
1501 	struct completion s_kobj_unregister;
1502 	struct super_block *s_sb;
1503 #ifdef CONFIG_UNICODE
1504 	struct unicode_map *s_encoding;
1505 	__u16 s_encoding_flags;
1506 #endif
1507 
1508 	/* Journaling */
1509 	struct journal_s *s_journal;
1510 	struct list_head s_orphan;
1511 	struct mutex s_orphan_lock;
1512 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1513 	unsigned long s_commit_interval;
1514 	u32 s_max_batch_time;
1515 	u32 s_min_batch_time;
1516 	struct block_device *s_journal_bdev;
1517 #ifdef CONFIG_QUOTA
1518 	/* Names of quota files with journalled quota */
1519 	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1520 	int s_jquota_fmt;			/* Format of quota to use */
1521 #endif
1522 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1523 	struct ext4_system_blocks __rcu *s_system_blks;
1524 
1525 #ifdef EXTENTS_STATS
1526 	/* ext4 extents stats */
1527 	unsigned long s_ext_min;
1528 	unsigned long s_ext_max;
1529 	unsigned long s_depth_max;
1530 	spinlock_t s_ext_stats_lock;
1531 	unsigned long s_ext_blocks;
1532 	unsigned long s_ext_extents;
1533 #endif
1534 
1535 	/* for buddy allocator */
1536 	struct ext4_group_info ** __rcu *s_group_info;
1537 	struct inode *s_buddy_cache;
1538 	spinlock_t s_md_lock;
1539 	unsigned short *s_mb_offsets;
1540 	unsigned int *s_mb_maxs;
1541 	unsigned int s_group_info_size;
1542 	unsigned int s_mb_free_pending;
1543 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1544 						   after commit completed */
1545 
1546 	/* tunables */
1547 	unsigned long s_stripe;
1548 	unsigned int s_mb_stream_request;
1549 	unsigned int s_mb_max_to_scan;
1550 	unsigned int s_mb_min_to_scan;
1551 	unsigned int s_mb_stats;
1552 	unsigned int s_mb_order2_reqs;
1553 	unsigned int s_mb_group_prealloc;
1554 	unsigned int s_mb_max_inode_prealloc;
1555 	unsigned int s_max_dir_size_kb;
1556 	/* where last allocation was done - for stream allocation */
1557 	unsigned long s_mb_last_group;
1558 	unsigned long s_mb_last_start;
1559 	unsigned int s_mb_prefetch;
1560 	unsigned int s_mb_prefetch_limit;
1561 
1562 	/* stats for buddy allocator */
1563 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1564 	atomic_t s_bal_success;	/* we found long enough chunks */
1565 	atomic_t s_bal_allocated;	/* in blocks */
1566 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1567 	atomic_t s_bal_goals;	/* goal hits */
1568 	atomic_t s_bal_breaks;	/* too long searches */
1569 	atomic_t s_bal_2orders;	/* 2^order hits */
1570 	spinlock_t s_bal_lock;
1571 	unsigned long s_mb_buddies_generated;
1572 	unsigned long long s_mb_generation_time;
1573 	atomic_t s_mb_lost_chunks;
1574 	atomic_t s_mb_preallocated;
1575 	atomic_t s_mb_discarded;
1576 	atomic_t s_lock_busy;
1577 
1578 	/* locality groups */
1579 	struct ext4_locality_group __percpu *s_locality_groups;
1580 
1581 	/* for write statistics */
1582 	unsigned long s_sectors_written_start;
1583 	u64 s_kbytes_written;
1584 
1585 	/* the size of zero-out chunk */
1586 	unsigned int s_extent_max_zeroout_kb;
1587 
1588 	unsigned int s_log_groups_per_flex;
1589 	struct flex_groups * __rcu *s_flex_groups;
1590 	ext4_group_t s_flex_groups_allocated;
1591 
1592 	/* workqueue for reserved extent conversions (buffered io) */
1593 	struct workqueue_struct *rsv_conversion_wq;
1594 
1595 	/* timer for periodic error stats printing */
1596 	struct timer_list s_err_report;
1597 
1598 	/* Lazy inode table initialization info */
1599 	struct ext4_li_request *s_li_request;
1600 	/* Wait multiplier for lazy initialization thread */
1601 	unsigned int s_li_wait_mult;
1602 
1603 	/* Kernel thread for multiple mount protection */
1604 	struct task_struct *s_mmp_tsk;
1605 
1606 	/* record the last minlen when FITRIM is called. */
1607 	atomic_t s_last_trim_minblks;
1608 
1609 	/* Reference to checksum algorithm driver via cryptoapi */
1610 	struct crypto_shash *s_chksum_driver;
1611 
1612 	/* Precomputed FS UUID checksum for seeding other checksums */
1613 	__u32 s_csum_seed;
1614 
1615 	/* Reclaim extents from extent status tree */
1616 	struct shrinker s_es_shrinker;
1617 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1618 	long s_es_nr_inode;
1619 	struct ext4_es_stats s_es_stats;
1620 	struct mb_cache *s_ea_block_cache;
1621 	struct mb_cache *s_ea_inode_cache;
1622 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1623 
1624 	/* Ratelimit ext4 messages. */
1625 	struct ratelimit_state s_err_ratelimit_state;
1626 	struct ratelimit_state s_warning_ratelimit_state;
1627 	struct ratelimit_state s_msg_ratelimit_state;
1628 	atomic_t s_warning_count;
1629 	atomic_t s_msg_count;
1630 
1631 	/* Encryption policy for '-o test_dummy_encryption' */
1632 	struct fscrypt_dummy_policy s_dummy_enc_policy;
1633 
1634 	/*
1635 	 * Barrier between writepages ops and changing any inode's JOURNAL_DATA
1636 	 * or EXTENTS flag.
1637 	 */
1638 	struct percpu_rw_semaphore s_writepages_rwsem;
1639 	struct dax_device *s_daxdev;
1640 #ifdef CONFIG_EXT4_DEBUG
1641 	unsigned long s_simulate_fail;
1642 #endif
1643 	/* Record the errseq of the backing block device */
1644 	errseq_t s_bdev_wb_err;
1645 	spinlock_t s_bdev_wb_lock;
1646 
1647 	/* Ext4 fast commit stuff */
1648 	atomic_t s_fc_subtid;
1649 	atomic_t s_fc_ineligible_updates;
1650 	/*
1651 	 * After commit starts, the main queue gets locked, and the further
1652 	 * updates get added in the staging queue.
1653 	 */
1654 #define FC_Q_MAIN	0
1655 #define FC_Q_STAGING	1
1656 	struct list_head s_fc_q[2];	/* Inodes staged for fast commit
1657 					 * that have data changes in them.
1658 					 */
1659 	struct list_head s_fc_dentry_q[2];	/* directory entry updates */
1660 	unsigned int s_fc_bytes;
1661 	/*
1662 	 * Main fast commit lock. This lock protects accesses to the
1663 	 * following fields:
1664 	 * ei->i_fc_list, s_fc_dentry_q, s_fc_q, s_fc_bytes, s_fc_bh.
1665 	 */
1666 	spinlock_t s_fc_lock;
1667 	struct buffer_head *s_fc_bh;
1668 	struct ext4_fc_stats s_fc_stats;
1669 	u64 s_fc_avg_commit_time;
1670 #ifdef CONFIG_EXT4_DEBUG
1671 	int s_fc_debug_max_replay;
1672 #endif
1673 	struct ext4_fc_replay_state s_fc_replay_state;
1674 };
1675 
1676 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1677 {
1678 	return sb->s_fs_info;
1679 }
1680 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1681 {
1682 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1683 }
1684 
1685 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1686 {
1687 	return ino == EXT4_ROOT_INO ||
1688 		(ino >= EXT4_FIRST_INO(sb) &&
1689 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1690 }
1691 
1692 /*
1693  * Returns: sbi->field[index]
1694  * Used to access an array element from the following sbi fields which require
1695  * rcu protection to avoid dereferencing an invalid pointer due to reassignment
1696  * - s_group_desc
1697  * - s_group_info
1698  * - s_flex_group
1699  */
1700 #define sbi_array_rcu_deref(sbi, field, index)				   \
1701 ({									   \
1702 	typeof(*((sbi)->field)) _v;					   \
1703 	rcu_read_lock();						   \
1704 	_v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index];	   \
1705 	rcu_read_unlock();						   \
1706 	_v;								   \
1707 })
1708 
1709 /*
1710  * Simulate_fail codes
1711  */
1712 #define EXT4_SIM_BBITMAP_EIO	1
1713 #define EXT4_SIM_BBITMAP_CRC	2
1714 #define EXT4_SIM_IBITMAP_EIO	3
1715 #define EXT4_SIM_IBITMAP_CRC	4
1716 #define EXT4_SIM_INODE_EIO	5
1717 #define EXT4_SIM_INODE_CRC	6
1718 #define EXT4_SIM_DIRBLOCK_EIO	7
1719 #define EXT4_SIM_DIRBLOCK_CRC	8
1720 
1721 static inline bool ext4_simulate_fail(struct super_block *sb,
1722 				     unsigned long code)
1723 {
1724 #ifdef CONFIG_EXT4_DEBUG
1725 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1726 
1727 	if (unlikely(sbi->s_simulate_fail == code)) {
1728 		sbi->s_simulate_fail = 0;
1729 		return true;
1730 	}
1731 #endif
1732 	return false;
1733 }
1734 
1735 static inline void ext4_simulate_fail_bh(struct super_block *sb,
1736 					 struct buffer_head *bh,
1737 					 unsigned long code)
1738 {
1739 	if (!IS_ERR(bh) && ext4_simulate_fail(sb, code))
1740 		clear_buffer_uptodate(bh);
1741 }
1742 
1743 /*
1744  * Error number codes for s_{first,last}_error_errno
1745  *
1746  * Linux errno numbers are architecture specific, so we need to translate
1747  * them into something which is architecture independent.   We don't define
1748  * codes for all errno's; just the ones which are most likely to be the cause
1749  * of an ext4_error() call.
1750  */
1751 #define EXT4_ERR_UNKNOWN	 1
1752 #define EXT4_ERR_EIO		 2
1753 #define EXT4_ERR_ENOMEM		 3
1754 #define EXT4_ERR_EFSBADCRC	 4
1755 #define EXT4_ERR_EFSCORRUPTED	 5
1756 #define EXT4_ERR_ENOSPC		 6
1757 #define EXT4_ERR_ENOKEY		 7
1758 #define EXT4_ERR_EROFS		 8
1759 #define EXT4_ERR_EFBIG		 9
1760 #define EXT4_ERR_EEXIST		10
1761 #define EXT4_ERR_ERANGE		11
1762 #define EXT4_ERR_EOVERFLOW	12
1763 #define EXT4_ERR_EBUSY		13
1764 #define EXT4_ERR_ENOTDIR	14
1765 #define EXT4_ERR_ENOTEMPTY	15
1766 #define EXT4_ERR_ESHUTDOWN	16
1767 #define EXT4_ERR_EFAULT		17
1768 
1769 /*
1770  * Inode dynamic state flags
1771  */
1772 enum {
1773 	EXT4_STATE_JDATA,		/* journaled data exists */
1774 	EXT4_STATE_NEW,			/* inode is newly created */
1775 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1776 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1777 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1778 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1779 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1780 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1781 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1782 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1783 	EXT4_STATE_VERITY_IN_PROGRESS,	/* building fs-verity Merkle tree */
1784 	EXT4_STATE_FC_COMMITTING,	/* Fast commit ongoing */
1785 };
1786 
1787 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1788 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1789 {									\
1790 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1791 }									\
1792 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1793 {									\
1794 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1795 }									\
1796 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1797 {									\
1798 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1799 }
1800 
1801 /* Add these declarations here only so that these functions can be
1802  * found by name.  Otherwise, they are very hard to locate. */
1803 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1804 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1805 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1806 EXT4_INODE_BIT_FNS(flag, flags, 0)
1807 
1808 /* Add these declarations here only so that these functions can be
1809  * found by name.  Otherwise, they are very hard to locate. */
1810 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1811 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1812 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1813 #if (BITS_PER_LONG < 64)
1814 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1815 
1816 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1817 {
1818 	(ei)->i_state_flags = 0;
1819 }
1820 #else
1821 EXT4_INODE_BIT_FNS(state, flags, 32)
1822 
1823 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1824 {
1825 	/* We depend on the fact that callers will set i_flags */
1826 }
1827 #endif
1828 #else
1829 /* Assume that user mode programs are passing in an ext4fs superblock, not
1830  * a kernel struct super_block.  This will allow us to call the feature-test
1831  * macros from user land. */
1832 #define EXT4_SB(sb)	(sb)
1833 #endif
1834 
1835 static inline bool ext4_verity_in_progress(struct inode *inode)
1836 {
1837 	return IS_ENABLED(CONFIG_FS_VERITY) &&
1838 	       ext4_test_inode_state(inode, EXT4_STATE_VERITY_IN_PROGRESS);
1839 }
1840 
1841 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1842 
1843 /*
1844  * Codes for operating systems
1845  */
1846 #define EXT4_OS_LINUX		0
1847 #define EXT4_OS_HURD		1
1848 #define EXT4_OS_MASIX		2
1849 #define EXT4_OS_FREEBSD		3
1850 #define EXT4_OS_LITES		4
1851 
1852 /*
1853  * Revision levels
1854  */
1855 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1856 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1857 
1858 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1859 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1860 
1861 #define EXT4_GOOD_OLD_INODE_SIZE 128
1862 
1863 #define EXT4_EXTRA_TIMESTAMP_MAX	(((s64)1 << 34) - 1  + S32_MIN)
1864 #define EXT4_NON_EXTRA_TIMESTAMP_MAX	S32_MAX
1865 #define EXT4_TIMESTAMP_MIN		S32_MIN
1866 
1867 /*
1868  * Feature set definitions
1869  */
1870 
1871 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1872 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1873 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1874 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1875 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1876 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1877 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1878 #define EXT4_FEATURE_COMPAT_FAST_COMMIT		0x0400
1879 #define EXT4_FEATURE_COMPAT_STABLE_INODES	0x0800
1880 
1881 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1882 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1883 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1884 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1885 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1886 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1887 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1888 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1889 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1890 /*
1891  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1892  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1893  * all other data structures' checksums.  However, the METADATA_CSUM and
1894  * GDT_CSUM bits are mutually exclusive.
1895  */
1896 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1897 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1898 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1899 #define EXT4_FEATURE_RO_COMPAT_VERITY		0x8000
1900 
1901 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1902 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1903 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1904 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1905 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1906 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1907 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1908 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1909 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1910 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1911 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1912 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1913 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1914 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1915 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1916 #define EXT4_FEATURE_INCOMPAT_CASEFOLD		0x20000
1917 
1918 extern void ext4_update_dynamic_rev(struct super_block *sb);
1919 
1920 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1921 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1922 { \
1923 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1924 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1925 } \
1926 static inline void ext4_set_feature_##name(struct super_block *sb) \
1927 { \
1928 	ext4_update_dynamic_rev(sb); \
1929 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1930 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1931 } \
1932 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1933 { \
1934 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1935 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1936 }
1937 
1938 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1939 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1940 { \
1941 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1942 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1943 } \
1944 static inline void ext4_set_feature_##name(struct super_block *sb) \
1945 { \
1946 	ext4_update_dynamic_rev(sb); \
1947 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1948 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1949 } \
1950 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1951 { \
1952 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1953 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1954 }
1955 
1956 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1957 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1958 { \
1959 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1960 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1961 } \
1962 static inline void ext4_set_feature_##name(struct super_block *sb) \
1963 { \
1964 	ext4_update_dynamic_rev(sb); \
1965 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
1966 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1967 } \
1968 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1969 { \
1970 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1971 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1972 }
1973 
1974 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1975 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1976 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1977 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1978 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1979 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1980 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1981 EXT4_FEATURE_COMPAT_FUNCS(fast_commit,		FAST_COMMIT)
1982 EXT4_FEATURE_COMPAT_FUNCS(stable_inodes,	STABLE_INODES)
1983 
1984 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1985 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1986 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1987 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1988 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1989 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1990 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1991 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1992 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1993 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1994 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1995 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1996 EXT4_FEATURE_RO_COMPAT_FUNCS(verity,		VERITY)
1997 
1998 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1999 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
2000 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
2001 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
2002 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
2003 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
2004 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
2005 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
2006 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
2007 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
2008 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
2009 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
2010 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
2011 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
2012 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
2013 EXT4_FEATURE_INCOMPAT_FUNCS(casefold,		CASEFOLD)
2014 
2015 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2016 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2017 					 EXT4_FEATURE_INCOMPAT_META_BG)
2018 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2019 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2020 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2021 
2022 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2023 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2024 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
2025 					 EXT4_FEATURE_INCOMPAT_META_BG)
2026 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2027 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2028 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
2029 
2030 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
2031 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
2032 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
2033 					 EXT4_FEATURE_INCOMPAT_META_BG| \
2034 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
2035 					 EXT4_FEATURE_INCOMPAT_64BIT| \
2036 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
2037 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
2038 					 EXT4_FEATURE_INCOMPAT_MMP | \
2039 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
2040 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
2041 					 EXT4_FEATURE_INCOMPAT_CASEFOLD | \
2042 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
2043 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
2044 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
2045 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
2046 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
2047 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
2048 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
2049 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
2050 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
2051 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
2052 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
2053 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
2054 					 EXT4_FEATURE_RO_COMPAT_PROJECT |\
2055 					 EXT4_FEATURE_RO_COMPAT_VERITY)
2056 
2057 #define EXTN_FEATURE_FUNCS(ver) \
2058 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
2059 { \
2060 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
2061 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
2062 } \
2063 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
2064 { \
2065 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
2066 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
2067 } \
2068 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
2069 { \
2070 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
2071 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
2072 }
2073 
2074 EXTN_FEATURE_FUNCS(2)
2075 EXTN_FEATURE_FUNCS(3)
2076 EXTN_FEATURE_FUNCS(4)
2077 
2078 static inline bool ext4_has_compat_features(struct super_block *sb)
2079 {
2080 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
2081 }
2082 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
2083 {
2084 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
2085 }
2086 static inline bool ext4_has_incompat_features(struct super_block *sb)
2087 {
2088 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
2089 }
2090 
2091 /*
2092  * Superblock flags
2093  */
2094 #define EXT4_FLAGS_RESIZING	0
2095 #define EXT4_FLAGS_SHUTDOWN	1
2096 #define EXT4_FLAGS_BDEV_IS_DAX	2
2097 
2098 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
2099 {
2100 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
2101 }
2102 
2103 
2104 /*
2105  * Default values for user and/or group using reserved blocks
2106  */
2107 #define	EXT4_DEF_RESUID		0
2108 #define	EXT4_DEF_RESGID		0
2109 
2110 /*
2111  * Default project ID
2112  */
2113 #define	EXT4_DEF_PROJID		0
2114 
2115 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
2116 
2117 /*
2118  * Default mount options
2119  */
2120 #define EXT4_DEFM_DEBUG		0x0001
2121 #define EXT4_DEFM_BSDGROUPS	0x0002
2122 #define EXT4_DEFM_XATTR_USER	0x0004
2123 #define EXT4_DEFM_ACL		0x0008
2124 #define EXT4_DEFM_UID16		0x0010
2125 #define EXT4_DEFM_JMODE		0x0060
2126 #define EXT4_DEFM_JMODE_DATA	0x0020
2127 #define EXT4_DEFM_JMODE_ORDERED	0x0040
2128 #define EXT4_DEFM_JMODE_WBACK	0x0060
2129 #define EXT4_DEFM_NOBARRIER	0x0100
2130 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
2131 #define EXT4_DEFM_DISCARD	0x0400
2132 #define EXT4_DEFM_NODELALLOC	0x0800
2133 
2134 /*
2135  * Default journal batch times
2136  */
2137 #define EXT4_DEF_MIN_BATCH_TIME	0
2138 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
2139 
2140 /*
2141  * Minimum number of groups in a flexgroup before we separate out
2142  * directories into the first block group of a flexgroup
2143  */
2144 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
2145 
2146 /*
2147  * Structure of a directory entry
2148  */
2149 #define EXT4_NAME_LEN 255
2150 
2151 struct ext4_dir_entry {
2152 	__le32	inode;			/* Inode number */
2153 	__le16	rec_len;		/* Directory entry length */
2154 	__le16	name_len;		/* Name length */
2155 	char	name[EXT4_NAME_LEN];	/* File name */
2156 };
2157 
2158 /*
2159  * The new version of the directory entry.  Since EXT4 structures are
2160  * stored in intel byte order, and the name_len field could never be
2161  * bigger than 255 chars, it's safe to reclaim the extra byte for the
2162  * file_type field.
2163  */
2164 struct ext4_dir_entry_2 {
2165 	__le32	inode;			/* Inode number */
2166 	__le16	rec_len;		/* Directory entry length */
2167 	__u8	name_len;		/* Name length */
2168 	__u8	file_type;		/* See file type macros EXT4_FT_* below */
2169 	char	name[EXT4_NAME_LEN];	/* File name */
2170 };
2171 
2172 /*
2173  * This is a bogus directory entry at the end of each leaf block that
2174  * records checksums.
2175  */
2176 struct ext4_dir_entry_tail {
2177 	__le32	det_reserved_zero1;	/* Pretend to be unused */
2178 	__le16	det_rec_len;		/* 12 */
2179 	__u8	det_reserved_zero2;	/* Zero name length */
2180 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
2181 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
2182 };
2183 
2184 #define EXT4_DIRENT_TAIL(block, blocksize) \
2185 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
2186 					((blocksize) - \
2187 					 sizeof(struct ext4_dir_entry_tail))))
2188 
2189 /*
2190  * Ext4 directory file types.  Only the low 3 bits are used.  The
2191  * other bits are reserved for now.
2192  */
2193 #define EXT4_FT_UNKNOWN		0
2194 #define EXT4_FT_REG_FILE	1
2195 #define EXT4_FT_DIR		2
2196 #define EXT4_FT_CHRDEV		3
2197 #define EXT4_FT_BLKDEV		4
2198 #define EXT4_FT_FIFO		5
2199 #define EXT4_FT_SOCK		6
2200 #define EXT4_FT_SYMLINK		7
2201 
2202 #define EXT4_FT_MAX		8
2203 
2204 #define EXT4_FT_DIR_CSUM	0xDE
2205 
2206 /*
2207  * EXT4_DIR_PAD defines the directory entries boundaries
2208  *
2209  * NOTE: It must be a multiple of 4
2210  */
2211 #define EXT4_DIR_PAD			4
2212 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
2213 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
2214 					 ~EXT4_DIR_ROUND)
2215 #define EXT4_MAX_REC_LEN		((1<<16)-1)
2216 
2217 /*
2218  * If we ever get support for fs block sizes > page_size, we'll need
2219  * to remove the #if statements in the next two functions...
2220  */
2221 static inline unsigned int
2222 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
2223 {
2224 	unsigned len = le16_to_cpu(dlen);
2225 
2226 #if (PAGE_SIZE >= 65536)
2227 	if (len == EXT4_MAX_REC_LEN || len == 0)
2228 		return blocksize;
2229 	return (len & 65532) | ((len & 3) << 16);
2230 #else
2231 	return len;
2232 #endif
2233 }
2234 
2235 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2236 {
2237 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
2238 		BUG();
2239 #if (PAGE_SIZE >= 65536)
2240 	if (len < 65536)
2241 		return cpu_to_le16(len);
2242 	if (len == blocksize) {
2243 		if (blocksize == 65536)
2244 			return cpu_to_le16(EXT4_MAX_REC_LEN);
2245 		else
2246 			return cpu_to_le16(0);
2247 	}
2248 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2249 #else
2250 	return cpu_to_le16(len);
2251 #endif
2252 }
2253 
2254 /*
2255  * Hash Tree Directory indexing
2256  * (c) Daniel Phillips, 2001
2257  */
2258 
2259 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2260 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2261 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2262 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2263 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2264 
2265 /* Legal values for the dx_root hash_version field: */
2266 
2267 #define DX_HASH_LEGACY			0
2268 #define DX_HASH_HALF_MD4		1
2269 #define DX_HASH_TEA			2
2270 #define DX_HASH_LEGACY_UNSIGNED		3
2271 #define DX_HASH_HALF_MD4_UNSIGNED	4
2272 #define DX_HASH_TEA_UNSIGNED		5
2273 
2274 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2275 			      const void *address, unsigned int length)
2276 {
2277 	struct {
2278 		struct shash_desc shash;
2279 		char ctx[4];
2280 	} desc;
2281 
2282 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2283 
2284 	desc.shash.tfm = sbi->s_chksum_driver;
2285 	*(u32 *)desc.ctx = crc;
2286 
2287 	BUG_ON(crypto_shash_update(&desc.shash, address, length));
2288 
2289 	return *(u32 *)desc.ctx;
2290 }
2291 
2292 #ifdef __KERNEL__
2293 
2294 /* hash info structure used by the directory hash */
2295 struct dx_hash_info
2296 {
2297 	u32		hash;
2298 	u32		minor_hash;
2299 	int		hash_version;
2300 	u32		*seed;
2301 };
2302 
2303 
2304 /* 32 and 64 bit signed EOF for dx directories */
2305 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2306 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2307 
2308 
2309 /*
2310  * Control parameters used by ext4_htree_next_block
2311  */
2312 #define HASH_NB_ALWAYS		1
2313 
2314 struct ext4_filename {
2315 	const struct qstr *usr_fname;
2316 	struct fscrypt_str disk_name;
2317 	struct dx_hash_info hinfo;
2318 #ifdef CONFIG_FS_ENCRYPTION
2319 	struct fscrypt_str crypto_buf;
2320 #endif
2321 #ifdef CONFIG_UNICODE
2322 	struct fscrypt_str cf_name;
2323 #endif
2324 };
2325 
2326 #define fname_name(p) ((p)->disk_name.name)
2327 #define fname_len(p)  ((p)->disk_name.len)
2328 
2329 /*
2330  * Describe an inode's exact location on disk and in memory
2331  */
2332 struct ext4_iloc
2333 {
2334 	struct buffer_head *bh;
2335 	unsigned long offset;
2336 	ext4_group_t block_group;
2337 };
2338 
2339 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2340 {
2341 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2342 }
2343 
2344 static inline bool ext4_is_quota_file(struct inode *inode)
2345 {
2346 	return IS_NOQUOTA(inode) &&
2347 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2348 }
2349 
2350 /*
2351  * This structure is stuffed into the struct file's private_data field
2352  * for directories.  It is where we put information so that we can do
2353  * readdir operations in hash tree order.
2354  */
2355 struct dir_private_info {
2356 	struct rb_root	root;
2357 	struct rb_node	*curr_node;
2358 	struct fname	*extra_fname;
2359 	loff_t		last_pos;
2360 	__u32		curr_hash;
2361 	__u32		curr_minor_hash;
2362 	__u32		next_hash;
2363 };
2364 
2365 /* calculate the first block number of the group */
2366 static inline ext4_fsblk_t
2367 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2368 {
2369 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2370 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2371 }
2372 
2373 /*
2374  * Special error return code only used by dx_probe() and its callers.
2375  */
2376 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2377 
2378 /* htree levels for ext4 */
2379 #define	EXT4_HTREE_LEVEL_COMPAT	2
2380 #define	EXT4_HTREE_LEVEL	3
2381 
2382 static inline int ext4_dir_htree_level(struct super_block *sb)
2383 {
2384 	return ext4_has_feature_largedir(sb) ?
2385 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2386 }
2387 
2388 /*
2389  * Timeout and state flag for lazy initialization inode thread.
2390  */
2391 #define EXT4_DEF_LI_WAIT_MULT			10
2392 #define EXT4_DEF_LI_MAX_START_DELAY		5
2393 #define EXT4_LAZYINIT_QUIT			0x0001
2394 #define EXT4_LAZYINIT_RUNNING			0x0002
2395 
2396 /*
2397  * Lazy inode table initialization info
2398  */
2399 struct ext4_lazy_init {
2400 	unsigned long		li_state;
2401 	struct list_head	li_request_list;
2402 	struct mutex		li_list_mtx;
2403 };
2404 
2405 enum ext4_li_mode {
2406 	EXT4_LI_MODE_PREFETCH_BBITMAP,
2407 	EXT4_LI_MODE_ITABLE,
2408 };
2409 
2410 struct ext4_li_request {
2411 	struct super_block	*lr_super;
2412 	enum ext4_li_mode	lr_mode;
2413 	ext4_group_t		lr_first_not_zeroed;
2414 	ext4_group_t		lr_next_group;
2415 	struct list_head	lr_request;
2416 	unsigned long		lr_next_sched;
2417 	unsigned long		lr_timeout;
2418 };
2419 
2420 struct ext4_features {
2421 	struct kobject f_kobj;
2422 	struct completion f_kobj_unregister;
2423 };
2424 
2425 /*
2426  * This structure will be used for multiple mount protection. It will be
2427  * written into the block number saved in the s_mmp_block field in the
2428  * superblock. Programs that check MMP should assume that if
2429  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2430  * to use the filesystem, regardless of how old the timestamp is.
2431  */
2432 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2433 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2434 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2435 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2436 
2437 struct mmp_struct {
2438 	__le32	mmp_magic;		/* Magic number for MMP */
2439 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2440 
2441 	/*
2442 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2443 	 * purposes and do not affect the correctness of the algorithm
2444 	 */
2445 	__le64	mmp_time;		/* Time last updated */
2446 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2447 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2448 
2449 	/*
2450 	 * mmp_check_interval is used to verify if the MMP block has been
2451 	 * updated on the block device. The value is updated based on the
2452 	 * maximum time to write the MMP block during an update cycle.
2453 	 */
2454 	__le16	mmp_check_interval;
2455 
2456 	__le16	mmp_pad1;
2457 	__le32	mmp_pad2[226];
2458 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2459 };
2460 
2461 /* arguments passed to the mmp thread */
2462 struct mmpd_data {
2463 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2464 	struct super_block *sb;  /* super block of the fs */
2465 };
2466 
2467 /*
2468  * Check interval multiplier
2469  * The MMP block is written every update interval and initially checked every
2470  * update interval x the multiplier (the value is then adapted based on the
2471  * write latency). The reason is that writes can be delayed under load and we
2472  * don't want readers to incorrectly assume that the filesystem is no longer
2473  * in use.
2474  */
2475 #define EXT4_MMP_CHECK_MULT		2UL
2476 
2477 /*
2478  * Minimum interval for MMP checking in seconds.
2479  */
2480 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2481 
2482 /*
2483  * Maximum interval for MMP checking in seconds.
2484  */
2485 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2486 
2487 /*
2488  * Function prototypes
2489  */
2490 
2491 /*
2492  * Ok, these declarations are also in <linux/kernel.h> but none of the
2493  * ext4 source programs needs to include it so they are duplicated here.
2494  */
2495 # define NORET_TYPE	/**/
2496 # define ATTRIB_NORET	__attribute__((noreturn))
2497 # define NORET_AND	noreturn,
2498 
2499 /* bitmap.c */
2500 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2501 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2502 				struct ext4_group_desc *gdp,
2503 				struct buffer_head *bh, int sz);
2504 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2505 				  struct ext4_group_desc *gdp,
2506 				  struct buffer_head *bh, int sz);
2507 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2508 				struct ext4_group_desc *gdp,
2509 				struct buffer_head *bh);
2510 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2511 				  struct ext4_group_desc *gdp,
2512 				  struct buffer_head *bh);
2513 
2514 /* balloc.c */
2515 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2516 					 ext4_fsblk_t blocknr,
2517 					 ext4_group_t *blockgrpp,
2518 					 ext4_grpblk_t *offsetp);
2519 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2520 					  ext4_fsblk_t block);
2521 
2522 extern unsigned int ext4_block_group(struct super_block *sb,
2523 			ext4_fsblk_t blocknr);
2524 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2525 			ext4_fsblk_t blocknr);
2526 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2527 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2528 			ext4_group_t group);
2529 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2530 					 ext4_fsblk_t goal,
2531 					 unsigned int flags,
2532 					 unsigned long *count,
2533 					 int *errp);
2534 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2535 				    s64 nclusters, unsigned int flags);
2536 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2537 extern void ext4_check_blocks_bitmap(struct super_block *);
2538 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2539 						    ext4_group_t block_group,
2540 						    struct buffer_head ** bh);
2541 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2542 
2543 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2544 						ext4_group_t block_group,
2545 						bool ignore_locked);
2546 extern int ext4_wait_block_bitmap(struct super_block *sb,
2547 				  ext4_group_t block_group,
2548 				  struct buffer_head *bh);
2549 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2550 						  ext4_group_t block_group);
2551 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2552 					      ext4_group_t block_group,
2553 					      struct ext4_group_desc *gdp);
2554 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2555 
2556 #ifdef CONFIG_UNICODE
2557 extern void ext4_fname_setup_ci_filename(struct inode *dir,
2558 					 const struct qstr *iname,
2559 					 struct fscrypt_str *fname);
2560 #endif
2561 
2562 #ifdef CONFIG_FS_ENCRYPTION
2563 static inline void ext4_fname_from_fscrypt_name(struct ext4_filename *dst,
2564 						const struct fscrypt_name *src)
2565 {
2566 	memset(dst, 0, sizeof(*dst));
2567 
2568 	dst->usr_fname = src->usr_fname;
2569 	dst->disk_name = src->disk_name;
2570 	dst->hinfo.hash = src->hash;
2571 	dst->hinfo.minor_hash = src->minor_hash;
2572 	dst->crypto_buf = src->crypto_buf;
2573 }
2574 
2575 static inline int ext4_fname_setup_filename(struct inode *dir,
2576 					    const struct qstr *iname,
2577 					    int lookup,
2578 					    struct ext4_filename *fname)
2579 {
2580 	struct fscrypt_name name;
2581 	int err;
2582 
2583 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2584 	if (err)
2585 		return err;
2586 
2587 	ext4_fname_from_fscrypt_name(fname, &name);
2588 
2589 #ifdef CONFIG_UNICODE
2590 	ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name);
2591 #endif
2592 	return 0;
2593 }
2594 
2595 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2596 					    struct dentry *dentry,
2597 					    struct ext4_filename *fname)
2598 {
2599 	struct fscrypt_name name;
2600 	int err;
2601 
2602 	err = fscrypt_prepare_lookup(dir, dentry, &name);
2603 	if (err)
2604 		return err;
2605 
2606 	ext4_fname_from_fscrypt_name(fname, &name);
2607 
2608 #ifdef CONFIG_UNICODE
2609 	ext4_fname_setup_ci_filename(dir, &dentry->d_name, &fname->cf_name);
2610 #endif
2611 	return 0;
2612 }
2613 
2614 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2615 {
2616 	struct fscrypt_name name;
2617 
2618 	name.crypto_buf = fname->crypto_buf;
2619 	fscrypt_free_filename(&name);
2620 
2621 	fname->crypto_buf.name = NULL;
2622 	fname->usr_fname = NULL;
2623 	fname->disk_name.name = NULL;
2624 
2625 #ifdef CONFIG_UNICODE
2626 	kfree(fname->cf_name.name);
2627 	fname->cf_name.name = NULL;
2628 #endif
2629 }
2630 #else /* !CONFIG_FS_ENCRYPTION */
2631 static inline int ext4_fname_setup_filename(struct inode *dir,
2632 					    const struct qstr *iname,
2633 					    int lookup,
2634 					    struct ext4_filename *fname)
2635 {
2636 	fname->usr_fname = iname;
2637 	fname->disk_name.name = (unsigned char *) iname->name;
2638 	fname->disk_name.len = iname->len;
2639 
2640 #ifdef CONFIG_UNICODE
2641 	ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name);
2642 #endif
2643 
2644 	return 0;
2645 }
2646 
2647 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2648 					    struct dentry *dentry,
2649 					    struct ext4_filename *fname)
2650 {
2651 	return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
2652 }
2653 
2654 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2655 {
2656 #ifdef CONFIG_UNICODE
2657 	kfree(fname->cf_name.name);
2658 	fname->cf_name.name = NULL;
2659 #endif
2660 }
2661 #endif /* !CONFIG_FS_ENCRYPTION */
2662 
2663 /* dir.c */
2664 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2665 				  struct file *,
2666 				  struct ext4_dir_entry_2 *,
2667 				  struct buffer_head *, char *, int,
2668 				  unsigned int);
2669 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2670 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2671 					(de), (bh), (buf), (size), (offset)))
2672 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2673 				__u32 minor_hash,
2674 				struct ext4_dir_entry_2 *dirent,
2675 				struct fscrypt_str *ent_name);
2676 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2677 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2678 			     struct buffer_head *bh,
2679 			     void *buf, int buf_size,
2680 			     struct ext4_filename *fname,
2681 			     struct ext4_dir_entry_2 **dest_de);
2682 void ext4_insert_dentry(struct inode *inode,
2683 			struct ext4_dir_entry_2 *de,
2684 			int buf_size,
2685 			struct ext4_filename *fname);
2686 static inline void ext4_update_dx_flag(struct inode *inode)
2687 {
2688 	if (!ext4_has_feature_dir_index(inode->i_sb)) {
2689 		/* ext4_iget() should have caught this... */
2690 		WARN_ON_ONCE(ext4_has_feature_metadata_csum(inode->i_sb));
2691 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2692 	}
2693 }
2694 static const unsigned char ext4_filetype_table[] = {
2695 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2696 };
2697 
2698 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2699 {
2700 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2701 		return DT_UNKNOWN;
2702 
2703 	return ext4_filetype_table[filetype];
2704 }
2705 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2706 			     void *buf, int buf_size);
2707 
2708 /* fsync.c */
2709 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2710 
2711 /* hash.c */
2712 extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
2713 			  struct dx_hash_info *hinfo);
2714 
2715 /* ialloc.c */
2716 extern int ext4_mark_inode_used(struct super_block *sb, int ino);
2717 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2718 				      const struct qstr *qstr, __u32 goal,
2719 				      uid_t *owner, __u32 i_flags,
2720 				      int handle_type, unsigned int line_no,
2721 				      int nblocks);
2722 
2723 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2724 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2725 			 i_flags, 0, 0, 0)
2726 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2727 				    type, nblocks)		    \
2728 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2729 			 0, (type), __LINE__, (nblocks))
2730 
2731 
2732 extern void ext4_free_inode(handle_t *, struct inode *);
2733 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2734 extern unsigned long ext4_count_free_inodes(struct super_block *);
2735 extern unsigned long ext4_count_dirs(struct super_block *);
2736 extern void ext4_check_inodes_bitmap(struct super_block *);
2737 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2738 extern int ext4_init_inode_table(struct super_block *sb,
2739 				 ext4_group_t group, int barrier);
2740 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2741 
2742 /* fast_commit.c */
2743 int ext4_fc_info_show(struct seq_file *seq, void *v);
2744 void ext4_fc_init(struct super_block *sb, journal_t *journal);
2745 void ext4_fc_init_inode(struct inode *inode);
2746 void ext4_fc_track_range(struct inode *inode, ext4_lblk_t start,
2747 			 ext4_lblk_t end);
2748 void ext4_fc_track_unlink(struct inode *inode, struct dentry *dentry);
2749 void ext4_fc_track_link(struct inode *inode, struct dentry *dentry);
2750 void ext4_fc_track_create(struct inode *inode, struct dentry *dentry);
2751 void ext4_fc_track_inode(struct inode *inode);
2752 void ext4_fc_mark_ineligible(struct super_block *sb, int reason);
2753 void ext4_fc_start_ineligible(struct super_block *sb, int reason);
2754 void ext4_fc_stop_ineligible(struct super_block *sb);
2755 void ext4_fc_start_update(struct inode *inode);
2756 void ext4_fc_stop_update(struct inode *inode);
2757 void ext4_fc_del(struct inode *inode);
2758 bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block);
2759 void ext4_fc_replay_cleanup(struct super_block *sb);
2760 int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
2761 int __init ext4_fc_init_dentry_cache(void);
2762 
2763 /* mballoc.c */
2764 extern const struct seq_operations ext4_mb_seq_groups_ops;
2765 extern long ext4_mb_stats;
2766 extern long ext4_mb_max_to_scan;
2767 extern int ext4_mb_init(struct super_block *);
2768 extern int ext4_mb_release(struct super_block *);
2769 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2770 				struct ext4_allocation_request *, int *);
2771 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2772 extern void ext4_discard_preallocations(struct inode *, unsigned int);
2773 extern int __init ext4_init_mballoc(void);
2774 extern void ext4_exit_mballoc(void);
2775 extern ext4_group_t ext4_mb_prefetch(struct super_block *sb,
2776 				     ext4_group_t group,
2777 				     unsigned int nr, int *cnt);
2778 extern void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group,
2779 				  unsigned int nr);
2780 
2781 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2782 			     struct buffer_head *bh, ext4_fsblk_t block,
2783 			     unsigned long count, int flags);
2784 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2785 				   ext4_group_t ngroups);
2786 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2787 		ext4_group_t i, struct ext4_group_desc *desc);
2788 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2789 				ext4_fsblk_t block, unsigned long count);
2790 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2791 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2792 extern void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block,
2793 		       int len, int state);
2794 
2795 /* inode.c */
2796 void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
2797 			 struct ext4_inode_info *ei);
2798 int ext4_inode_is_fast_symlink(struct inode *inode);
2799 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2800 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2801 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2802 		     bool wait, struct buffer_head **bhs);
2803 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2804 			     struct buffer_head *bh_result, int create);
2805 int ext4_get_block(struct inode *inode, sector_t iblock,
2806 		   struct buffer_head *bh_result, int create);
2807 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2808 			   struct buffer_head *bh, int create);
2809 int ext4_walk_page_buffers(handle_t *handle,
2810 			   struct buffer_head *head,
2811 			   unsigned from,
2812 			   unsigned to,
2813 			   int *partial,
2814 			   int (*fn)(handle_t *handle,
2815 				     struct buffer_head *bh));
2816 int do_journal_get_write_access(handle_t *handle,
2817 				struct buffer_head *bh);
2818 #define FALL_BACK_TO_NONDELALLOC 1
2819 #define CONVERT_INLINE_DATA	 2
2820 
2821 typedef enum {
2822 	EXT4_IGET_NORMAL =	0,
2823 	EXT4_IGET_SPECIAL =	0x0001, /* OK to iget a system inode */
2824 	EXT4_IGET_HANDLE = 	0x0002	/* Inode # is from a handle */
2825 } ext4_iget_flags;
2826 
2827 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2828 				 ext4_iget_flags flags, const char *function,
2829 				 unsigned int line);
2830 
2831 #define ext4_iget(sb, ino, flags) \
2832 	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2833 
2834 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2835 extern int  ext4_setattr(struct dentry *, struct iattr *);
2836 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2837 extern void ext4_evict_inode(struct inode *);
2838 extern void ext4_clear_inode(struct inode *);
2839 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2840 extern int  ext4_sync_inode(handle_t *, struct inode *);
2841 extern void ext4_dirty_inode(struct inode *, int);
2842 extern int ext4_change_inode_journal_flag(struct inode *, int);
2843 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2844 extern int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino,
2845 			  struct ext4_iloc *iloc);
2846 extern int ext4_inode_attach_jinode(struct inode *inode);
2847 extern int ext4_can_truncate(struct inode *inode);
2848 extern int ext4_truncate(struct inode *);
2849 extern int ext4_break_layouts(struct inode *);
2850 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2851 extern void ext4_set_inode_flags(struct inode *, bool init);
2852 extern int ext4_alloc_da_blocks(struct inode *inode);
2853 extern void ext4_set_aops(struct inode *inode);
2854 extern int ext4_writepage_trans_blocks(struct inode *);
2855 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2856 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2857 			     loff_t lstart, loff_t lend);
2858 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
2859 extern vm_fault_t ext4_filemap_fault(struct vm_fault *vmf);
2860 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2861 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2862 extern void ext4_da_release_space(struct inode *inode, int to_free);
2863 extern void ext4_da_update_reserve_space(struct inode *inode,
2864 					int used, int quota_claim);
2865 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2866 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2867 
2868 /* indirect.c */
2869 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2870 				struct ext4_map_blocks *map, int flags);
2871 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2872 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2873 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2874 				 ext4_lblk_t start, ext4_lblk_t end);
2875 
2876 /* ioctl.c */
2877 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2878 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2879 extern void ext4_reset_inode_seed(struct inode *inode);
2880 
2881 /* migrate.c */
2882 extern int ext4_ext_migrate(struct inode *);
2883 extern int ext4_ind_migrate(struct inode *inode);
2884 
2885 /* namei.c */
2886 extern int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2887 			     struct inode *inode);
2888 extern int ext4_dirblock_csum_verify(struct inode *inode,
2889 				     struct buffer_head *bh);
2890 extern int ext4_orphan_add(handle_t *, struct inode *);
2891 extern int ext4_orphan_del(handle_t *, struct inode *);
2892 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2893 				__u32 start_minor_hash, __u32 *next_hash);
2894 extern int ext4_search_dir(struct buffer_head *bh,
2895 			   char *search_buf,
2896 			   int buf_size,
2897 			   struct inode *dir,
2898 			   struct ext4_filename *fname,
2899 			   unsigned int offset,
2900 			   struct ext4_dir_entry_2 **res_dir);
2901 extern int ext4_generic_delete_entry(struct inode *dir,
2902 				     struct ext4_dir_entry_2 *de_del,
2903 				     struct buffer_head *bh,
2904 				     void *entry_buf,
2905 				     int buf_size,
2906 				     int csum_size);
2907 extern bool ext4_empty_dir(struct inode *inode);
2908 
2909 /* resize.c */
2910 extern void ext4_kvfree_array_rcu(void *to_free);
2911 extern int ext4_group_add(struct super_block *sb,
2912 				struct ext4_new_group_data *input);
2913 extern int ext4_group_extend(struct super_block *sb,
2914 				struct ext4_super_block *es,
2915 				ext4_fsblk_t n_blocks_count);
2916 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2917 
2918 /* super.c */
2919 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
2920 					 sector_t block, int op_flags);
2921 extern struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
2922 						   sector_t block);
2923 extern void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
2924 				bh_end_io_t *end_io);
2925 extern int ext4_read_bh(struct buffer_head *bh, int op_flags,
2926 			bh_end_io_t *end_io);
2927 extern int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait);
2928 extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
2929 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2930 extern int ext4_calculate_overhead(struct super_block *sb);
2931 extern void ext4_superblock_csum_set(struct super_block *sb);
2932 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2933 				    ext4_group_t ngroup);
2934 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2935 				     char nbuf[16]);
2936 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
2937 					     ext4_group_t block_group,
2938 					     unsigned int flags);
2939 
2940 extern __printf(6, 7)
2941 void __ext4_error(struct super_block *, const char *, unsigned int, int, __u64,
2942 		  const char *, ...);
2943 extern __printf(6, 7)
2944 void __ext4_error_inode(struct inode *, const char *, unsigned int,
2945 			ext4_fsblk_t, int, const char *, ...);
2946 extern __printf(5, 6)
2947 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2948 		     const char *, ...);
2949 extern void __ext4_std_error(struct super_block *, const char *,
2950 			     unsigned int, int);
2951 extern __printf(5, 6)
2952 void __ext4_abort(struct super_block *, const char *, unsigned int, int,
2953 		  const char *, ...);
2954 extern __printf(4, 5)
2955 void __ext4_warning(struct super_block *, const char *, unsigned int,
2956 		    const char *, ...);
2957 extern __printf(4, 5)
2958 void __ext4_warning_inode(const struct inode *inode, const char *function,
2959 			  unsigned int line, const char *fmt, ...);
2960 extern __printf(3, 4)
2961 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2962 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2963 			   const char *, unsigned int, const char *);
2964 extern __printf(7, 8)
2965 void __ext4_grp_locked_error(const char *, unsigned int,
2966 			     struct super_block *, ext4_group_t,
2967 			     unsigned long, ext4_fsblk_t,
2968 			     const char *, ...);
2969 
2970 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2971 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2972 
2973 #define EXT4_ERROR_INODE_ERR(inode, err, fmt, a...)			\
2974 	__ext4_error_inode((inode), __func__, __LINE__, 0, (err), (fmt), ## a)
2975 
2976 #define ext4_error_inode_block(inode, block, err, fmt, a...)		\
2977 	__ext4_error_inode((inode), __func__, __LINE__, (block), (err),	\
2978 			   (fmt), ## a)
2979 
2980 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2981 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2982 
2983 #ifdef CONFIG_PRINTK
2984 
2985 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2986 	__ext4_error_inode(inode, func, line, block, 0, fmt, ##__VA_ARGS__)
2987 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
2988 	__ext4_error_inode((inode), (func), (line), (block), 		\
2989 			   (err), (fmt), ##__VA_ARGS__)
2990 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2991 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2992 #define ext4_error(sb, fmt, ...)					\
2993 	__ext4_error((sb), __func__, __LINE__, 0, 0, (fmt), ##__VA_ARGS__)
2994 #define ext4_error_err(sb, err, fmt, ...)				\
2995 	__ext4_error((sb), __func__, __LINE__, (err), 0, (fmt), ##__VA_ARGS__)
2996 #define ext4_abort(sb, err, fmt, ...)					\
2997 	__ext4_abort((sb), __func__, __LINE__, (err), (fmt), ##__VA_ARGS__)
2998 #define ext4_warning(sb, fmt, ...)					\
2999 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
3000 #define ext4_warning_inode(inode, fmt, ...)				\
3001 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
3002 #define ext4_msg(sb, level, fmt, ...)				\
3003 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
3004 #define dump_mmp_msg(sb, mmp, msg)					\
3005 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
3006 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
3007 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
3008 				fmt, ##__VA_ARGS__)
3009 
3010 #else
3011 
3012 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
3013 do {									\
3014 	no_printk(fmt, ##__VA_ARGS__);					\
3015 	__ext4_error_inode(inode, "", 0, block, 0, " ");		\
3016 } while (0)
3017 #define ext4_error_inode_err(inode, func, line, block, err, fmt, ...)	\
3018 do {									\
3019 	no_printk(fmt, ##__VA_ARGS__);					\
3020 	__ext4_error_inode(inode, "", 0, block, err, " ");		\
3021 } while (0)
3022 #define ext4_error_file(file, func, line, block, fmt, ...)		\
3023 do {									\
3024 	no_printk(fmt, ##__VA_ARGS__);					\
3025 	__ext4_error_file(file, "", 0, block, " ");			\
3026 } while (0)
3027 #define ext4_error(sb, fmt, ...)					\
3028 do {									\
3029 	no_printk(fmt, ##__VA_ARGS__);					\
3030 	__ext4_error(sb, "", 0, 0, 0, " ");				\
3031 } while (0)
3032 #define ext4_error_err(sb, err, fmt, ...)				\
3033 do {									\
3034 	no_printk(fmt, ##__VA_ARGS__);					\
3035 	__ext4_error(sb, "", 0, err, 0, " ");				\
3036 } while (0)
3037 #define ext4_abort(sb, err, fmt, ...)					\
3038 do {									\
3039 	no_printk(fmt, ##__VA_ARGS__);					\
3040 	__ext4_abort(sb, "", 0, err, " ");				\
3041 } while (0)
3042 #define ext4_warning(sb, fmt, ...)					\
3043 do {									\
3044 	no_printk(fmt, ##__VA_ARGS__);					\
3045 	__ext4_warning(sb, "", 0, " ");					\
3046 } while (0)
3047 #define ext4_warning_inode(inode, fmt, ...)				\
3048 do {									\
3049 	no_printk(fmt, ##__VA_ARGS__);					\
3050 	__ext4_warning_inode(inode, "", 0, " ");			\
3051 } while (0)
3052 #define ext4_msg(sb, level, fmt, ...)					\
3053 do {									\
3054 	no_printk(fmt, ##__VA_ARGS__);					\
3055 	__ext4_msg(sb, "", " ");					\
3056 } while (0)
3057 #define dump_mmp_msg(sb, mmp, msg)					\
3058 	__dump_mmp_msg(sb, mmp, "", 0, "")
3059 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
3060 do {									\
3061 	no_printk(fmt, ##__VA_ARGS__);				\
3062 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
3063 } while (0)
3064 
3065 #endif
3066 
3067 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
3068 				      struct ext4_group_desc *bg);
3069 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
3070 				      struct ext4_group_desc *bg);
3071 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
3072 				     struct ext4_group_desc *bg);
3073 extern __u32 ext4_free_group_clusters(struct super_block *sb,
3074 				      struct ext4_group_desc *bg);
3075 extern __u32 ext4_free_inodes_count(struct super_block *sb,
3076 				 struct ext4_group_desc *bg);
3077 extern __u32 ext4_used_dirs_count(struct super_block *sb,
3078 				struct ext4_group_desc *bg);
3079 extern __u32 ext4_itable_unused_count(struct super_block *sb,
3080 				   struct ext4_group_desc *bg);
3081 extern void ext4_block_bitmap_set(struct super_block *sb,
3082 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3083 extern void ext4_inode_bitmap_set(struct super_block *sb,
3084 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
3085 extern void ext4_inode_table_set(struct super_block *sb,
3086 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
3087 extern void ext4_free_group_clusters_set(struct super_block *sb,
3088 					 struct ext4_group_desc *bg,
3089 					 __u32 count);
3090 extern void ext4_free_inodes_set(struct super_block *sb,
3091 				struct ext4_group_desc *bg, __u32 count);
3092 extern void ext4_used_dirs_set(struct super_block *sb,
3093 				struct ext4_group_desc *bg, __u32 count);
3094 extern void ext4_itable_unused_set(struct super_block *sb,
3095 				   struct ext4_group_desc *bg, __u32 count);
3096 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
3097 				       struct ext4_group_desc *gdp);
3098 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
3099 				     struct ext4_group_desc *gdp);
3100 extern int ext4_register_li_request(struct super_block *sb,
3101 				    ext4_group_t first_not_zeroed);
3102 
3103 static inline int ext4_has_metadata_csum(struct super_block *sb)
3104 {
3105 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
3106 		     !EXT4_SB(sb)->s_chksum_driver);
3107 
3108 	return ext4_has_feature_metadata_csum(sb) &&
3109 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
3110 }
3111 
3112 static inline int ext4_has_group_desc_csum(struct super_block *sb)
3113 {
3114 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
3115 }
3116 
3117 #define ext4_read_incompat_64bit_val(es, name) \
3118 	(((es)->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT) \
3119 		? (ext4_fsblk_t)le32_to_cpu(es->name##_hi) << 32 : 0) | \
3120 		le32_to_cpu(es->name##_lo))
3121 
3122 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
3123 {
3124 	return ext4_read_incompat_64bit_val(es, s_blocks_count);
3125 }
3126 
3127 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
3128 {
3129 	return ext4_read_incompat_64bit_val(es, s_r_blocks_count);
3130 }
3131 
3132 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
3133 {
3134 	return ext4_read_incompat_64bit_val(es, s_free_blocks_count);
3135 }
3136 
3137 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
3138 					 ext4_fsblk_t blk)
3139 {
3140 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
3141 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
3142 }
3143 
3144 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
3145 					      ext4_fsblk_t blk)
3146 {
3147 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
3148 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
3149 }
3150 
3151 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
3152 					   ext4_fsblk_t blk)
3153 {
3154 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
3155 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
3156 }
3157 
3158 static inline loff_t ext4_isize(struct super_block *sb,
3159 				struct ext4_inode *raw_inode)
3160 {
3161 	if (ext4_has_feature_largedir(sb) ||
3162 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
3163 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
3164 			le32_to_cpu(raw_inode->i_size_lo);
3165 
3166 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
3167 }
3168 
3169 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
3170 {
3171 	raw_inode->i_size_lo = cpu_to_le32(i_size);
3172 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
3173 }
3174 
3175 static inline
3176 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
3177 					    ext4_group_t group)
3178 {
3179 	 struct ext4_group_info **grp_info;
3180 	 long indexv, indexh;
3181 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
3182 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
3183 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
3184 	 grp_info = sbi_array_rcu_deref(EXT4_SB(sb), s_group_info, indexv);
3185 	 return grp_info[indexh];
3186 }
3187 
3188 /*
3189  * Reading s_groups_count requires using smp_rmb() afterwards.  See
3190  * the locking protocol documented in the comments of ext4_group_add()
3191  * in resize.c
3192  */
3193 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
3194 {
3195 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
3196 
3197 	smp_rmb();
3198 	return ngroups;
3199 }
3200 
3201 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
3202 					     ext4_group_t block_group)
3203 {
3204 	return block_group >> sbi->s_log_groups_per_flex;
3205 }
3206 
3207 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
3208 {
3209 	return 1 << sbi->s_log_groups_per_flex;
3210 }
3211 
3212 #define ext4_std_error(sb, errno)				\
3213 do {								\
3214 	if ((errno))						\
3215 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
3216 } while (0)
3217 
3218 #ifdef CONFIG_SMP
3219 /* Each CPU can accumulate percpu_counter_batch clusters in their local
3220  * counters. So we need to make sure we have free clusters more
3221  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
3222  */
3223 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
3224 #else
3225 #define EXT4_FREECLUSTERS_WATERMARK 0
3226 #endif
3227 
3228 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
3229 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
3230 {
3231 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
3232 		     !inode_is_locked(inode));
3233 	down_write(&EXT4_I(inode)->i_data_sem);
3234 	if (newsize > EXT4_I(inode)->i_disksize)
3235 		WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
3236 	up_write(&EXT4_I(inode)->i_data_sem);
3237 }
3238 
3239 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
3240 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
3241 {
3242 	int changed = 0;
3243 
3244 	if (newsize > inode->i_size) {
3245 		i_size_write(inode, newsize);
3246 		changed = 1;
3247 	}
3248 	if (newsize > EXT4_I(inode)->i_disksize) {
3249 		ext4_update_i_disksize(inode, newsize);
3250 		changed |= 2;
3251 	}
3252 	return changed;
3253 }
3254 
3255 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
3256 				      loff_t len);
3257 
3258 struct ext4_group_info {
3259 	unsigned long   bb_state;
3260 #ifdef AGGRESSIVE_CHECK
3261 	unsigned long	bb_check_counter;
3262 #endif
3263 	struct rb_root  bb_free_root;
3264 	ext4_grpblk_t	bb_first_free;	/* first free block */
3265 	ext4_grpblk_t	bb_free;	/* total free blocks */
3266 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
3267 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
3268 	struct          list_head bb_prealloc_list;
3269 #ifdef DOUBLE_CHECK
3270 	void            *bb_bitmap;
3271 #endif
3272 	struct rw_semaphore alloc_sem;
3273 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
3274 					 * regions, index is order.
3275 					 * bb_counters[3] = 5 means
3276 					 * 5 free 8-block regions. */
3277 };
3278 
3279 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
3280 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
3281 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
3282 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
3283 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT		\
3284 	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
3285 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT		\
3286 	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
3287 #define EXT4_GROUP_INFO_BBITMAP_READ_BIT	4
3288 
3289 #define EXT4_MB_GRP_NEED_INIT(grp)	\
3290 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
3291 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
3292 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3293 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
3294 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
3295 
3296 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
3297 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3298 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
3299 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3300 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
3301 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3302 #define EXT4_MB_GRP_TEST_AND_SET_READ(grp)	\
3303 	(test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_READ_BIT, &((grp)->bb_state)))
3304 
3305 #define EXT4_MAX_CONTENTION		8
3306 #define EXT4_CONTENTION_THRESHOLD	2
3307 
3308 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
3309 					      ext4_group_t group)
3310 {
3311 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
3312 }
3313 
3314 /*
3315  * Returns true if the filesystem is busy enough that attempts to
3316  * access the block group locks has run into contention.
3317  */
3318 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
3319 {
3320 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
3321 }
3322 
3323 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
3324 {
3325 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
3326 	if (spin_trylock(lock))
3327 		/*
3328 		 * We're able to grab the lock right away, so drop the
3329 		 * lock contention counter.
3330 		 */
3331 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
3332 	else {
3333 		/*
3334 		 * The lock is busy, so bump the contention counter,
3335 		 * and then wait on the spin lock.
3336 		 */
3337 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
3338 				  EXT4_MAX_CONTENTION);
3339 		spin_lock(lock);
3340 	}
3341 }
3342 
3343 static inline void ext4_unlock_group(struct super_block *sb,
3344 					ext4_group_t group)
3345 {
3346 	spin_unlock(ext4_group_lock_ptr(sb, group));
3347 }
3348 
3349 /*
3350  * Block validity checking
3351  */
3352 #define ext4_check_indirect_blockref(inode, bh)				\
3353 	ext4_check_blockref(__func__, __LINE__, inode,			\
3354 			    (__le32 *)(bh)->b_data,			\
3355 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3356 
3357 #define ext4_ind_check_inode(inode)					\
3358 	ext4_check_blockref(__func__, __LINE__, inode,			\
3359 			    EXT4_I(inode)->i_data,			\
3360 			    EXT4_NDIR_BLOCKS)
3361 
3362 /*
3363  * Inodes and files operations
3364  */
3365 
3366 /* dir.c */
3367 extern const struct file_operations ext4_dir_operations;
3368 
3369 #ifdef CONFIG_UNICODE
3370 extern const struct dentry_operations ext4_dentry_ops;
3371 #endif
3372 
3373 /* file.c */
3374 extern const struct inode_operations ext4_file_inode_operations;
3375 extern const struct file_operations ext4_file_operations;
3376 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
3377 
3378 /* inline.c */
3379 extern int ext4_get_max_inline_size(struct inode *inode);
3380 extern int ext4_find_inline_data_nolock(struct inode *inode);
3381 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
3382 				 unsigned int len);
3383 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3384 
3385 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
3386 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3387 					 struct inode *inode,
3388 					 loff_t pos, unsigned len,
3389 					 unsigned flags,
3390 					 struct page **pagep);
3391 extern int ext4_write_inline_data_end(struct inode *inode,
3392 				      loff_t pos, unsigned len,
3393 				      unsigned copied,
3394 				      struct page *page);
3395 extern struct buffer_head *
3396 ext4_journalled_write_inline_data(struct inode *inode,
3397 				  unsigned len,
3398 				  struct page *page);
3399 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3400 					   struct inode *inode,
3401 					   loff_t pos, unsigned len,
3402 					   unsigned flags,
3403 					   struct page **pagep,
3404 					   void **fsdata);
3405 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3406 					 unsigned len, unsigned copied,
3407 					 struct page *page);
3408 extern int ext4_try_add_inline_entry(handle_t *handle,
3409 				     struct ext4_filename *fname,
3410 				     struct inode *dir, struct inode *inode);
3411 extern int ext4_try_create_inline_dir(handle_t *handle,
3412 				      struct inode *parent,
3413 				      struct inode *inode);
3414 extern int ext4_read_inline_dir(struct file *filp,
3415 				struct dir_context *ctx,
3416 				int *has_inline_data);
3417 extern int ext4_inlinedir_to_tree(struct file *dir_file,
3418 				  struct inode *dir, ext4_lblk_t block,
3419 				  struct dx_hash_info *hinfo,
3420 				  __u32 start_hash, __u32 start_minor_hash,
3421 				  int *has_inline_data);
3422 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3423 					struct ext4_filename *fname,
3424 					struct ext4_dir_entry_2 **res_dir,
3425 					int *has_inline_data);
3426 extern int ext4_delete_inline_entry(handle_t *handle,
3427 				    struct inode *dir,
3428 				    struct ext4_dir_entry_2 *de_del,
3429 				    struct buffer_head *bh,
3430 				    int *has_inline_data);
3431 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3432 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3433 					struct ext4_dir_entry_2 **parent_de,
3434 					int *retval);
3435 extern int ext4_inline_data_fiemap(struct inode *inode,
3436 				   struct fiemap_extent_info *fieinfo,
3437 				   int *has_inline, __u64 start, __u64 len);
3438 
3439 struct iomap;
3440 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3441 
3442 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3443 
3444 extern int ext4_convert_inline_data(struct inode *inode);
3445 
3446 static inline int ext4_has_inline_data(struct inode *inode)
3447 {
3448 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3449 	       EXT4_I(inode)->i_inline_off;
3450 }
3451 
3452 /* namei.c */
3453 extern const struct inode_operations ext4_dir_inode_operations;
3454 extern const struct inode_operations ext4_special_inode_operations;
3455 extern struct dentry *ext4_get_parent(struct dentry *child);
3456 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3457 				 struct ext4_dir_entry_2 *de,
3458 				 int blocksize, int csum_size,
3459 				 unsigned int parent_ino, int dotdot_real_len);
3460 extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
3461 					unsigned int blocksize);
3462 extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
3463 				      struct buffer_head *bh);
3464 extern int ext4_ci_compare(const struct inode *parent,
3465 			   const struct qstr *fname,
3466 			   const struct qstr *entry, bool quick);
3467 extern int __ext4_unlink(struct inode *dir, const struct qstr *d_name,
3468 			 struct inode *inode);
3469 extern int __ext4_link(struct inode *dir, struct inode *inode,
3470 		       struct dentry *dentry);
3471 
3472 #define S_SHIFT 12
3473 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3474 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3475 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3476 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3477 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3478 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3479 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3480 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3481 };
3482 
3483 static inline void ext4_set_de_type(struct super_block *sb,
3484 				struct ext4_dir_entry_2 *de,
3485 				umode_t mode) {
3486 	if (ext4_has_feature_filetype(sb))
3487 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3488 }
3489 
3490 /* readpages.c */
3491 extern int ext4_mpage_readpages(struct inode *inode,
3492 		struct readahead_control *rac, struct page *page);
3493 extern int __init ext4_init_post_read_processing(void);
3494 extern void ext4_exit_post_read_processing(void);
3495 
3496 /* symlink.c */
3497 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3498 extern const struct inode_operations ext4_symlink_inode_operations;
3499 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3500 
3501 /* sysfs.c */
3502 extern int ext4_register_sysfs(struct super_block *sb);
3503 extern void ext4_unregister_sysfs(struct super_block *sb);
3504 extern int __init ext4_init_sysfs(void);
3505 extern void ext4_exit_sysfs(void);
3506 
3507 /* block_validity */
3508 extern void ext4_release_system_zone(struct super_block *sb);
3509 extern int ext4_setup_system_zone(struct super_block *sb);
3510 extern int __init ext4_init_system_zone(void);
3511 extern void ext4_exit_system_zone(void);
3512 extern int ext4_inode_block_valid(struct inode *inode,
3513 				  ext4_fsblk_t start_blk,
3514 				  unsigned int count);
3515 extern int ext4_check_blockref(const char *, unsigned int,
3516 			       struct inode *, __le32 *, unsigned int);
3517 
3518 /* extents.c */
3519 struct ext4_ext_path;
3520 struct ext4_extent;
3521 
3522 /*
3523  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3524  * __le32.
3525  */
3526 #define EXT_MAX_BLOCKS	0xffffffff
3527 
3528 extern void ext4_ext_tree_init(handle_t *handle, struct inode *inode);
3529 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3530 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3531 			       struct ext4_map_blocks *map, int flags);
3532 extern int ext4_ext_truncate(handle_t *, struct inode *);
3533 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3534 				 ext4_lblk_t end);
3535 extern void ext4_ext_init(struct super_block *);
3536 extern void ext4_ext_release(struct super_block *);
3537 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3538 			  loff_t len);
3539 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3540 					  loff_t offset, ssize_t len);
3541 extern int ext4_convert_unwritten_io_end_vec(handle_t *handle,
3542 					     ext4_io_end_t *io_end);
3543 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3544 			   struct ext4_map_blocks *map, int flags);
3545 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3546 						   int num,
3547 						   struct ext4_ext_path *path);
3548 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3549 				  struct ext4_ext_path **,
3550 				  struct ext4_extent *, int);
3551 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3552 					      struct ext4_ext_path **,
3553 					      int flags);
3554 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3555 extern int ext4_ext_check_inode(struct inode *inode);
3556 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3557 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3558 			__u64 start, __u64 len);
3559 extern int ext4_get_es_cache(struct inode *inode,
3560 			     struct fiemap_extent_info *fieinfo,
3561 			     __u64 start, __u64 len);
3562 extern int ext4_ext_precache(struct inode *inode);
3563 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3564 				struct inode *inode2, ext4_lblk_t lblk1,
3565 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3566 			     int mark_unwritten,int *err);
3567 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3568 extern int ext4_datasem_ensure_credits(handle_t *handle, struct inode *inode,
3569 				       int check_cred, int restart_cred,
3570 				       int revoke_cred);
3571 extern void ext4_ext_replay_shrink_inode(struct inode *inode, ext4_lblk_t end);
3572 extern int ext4_ext_replay_set_iblocks(struct inode *inode);
3573 extern int ext4_ext_replay_update_ex(struct inode *inode, ext4_lblk_t start,
3574 		int len, int unwritten, ext4_fsblk_t pblk);
3575 extern int ext4_ext_clear_bb(struct inode *inode);
3576 
3577 
3578 /* move_extent.c */
3579 extern void ext4_double_down_write_data_sem(struct inode *first,
3580 					    struct inode *second);
3581 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3582 					  struct inode *donor_inode);
3583 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3584 			     __u64 start_orig, __u64 start_donor,
3585 			     __u64 len, __u64 *moved_len);
3586 
3587 /* page-io.c */
3588 extern int __init ext4_init_pageio(void);
3589 extern void ext4_exit_pageio(void);
3590 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3591 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3592 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3593 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3594 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3595 				struct writeback_control *wbc);
3596 extern void ext4_end_io_rsv_work(struct work_struct *work);
3597 extern void ext4_io_submit(struct ext4_io_submit *io);
3598 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3599 			       struct page *page,
3600 			       int len,
3601 			       struct writeback_control *wbc,
3602 			       bool keep_towrite);
3603 extern struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end);
3604 extern struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end);
3605 
3606 /* mmp.c */
3607 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3608 
3609 /* verity.c */
3610 extern const struct fsverity_operations ext4_verityops;
3611 
3612 /*
3613  * Add new method to test whether block and inode bitmaps are properly
3614  * initialized. With uninit_bg reading the block from disk is not enough
3615  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3616  */
3617 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3618 
3619 static inline int bitmap_uptodate(struct buffer_head *bh)
3620 {
3621 	return (buffer_uptodate(bh) &&
3622 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3623 }
3624 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3625 {
3626 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3627 }
3628 
3629 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3630 
3631 /* For ioend & aio unwritten conversion wait queues */
3632 #define EXT4_WQ_HASH_SZ		37
3633 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3634 					    EXT4_WQ_HASH_SZ])
3635 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3636 
3637 extern int ext4_resize_begin(struct super_block *sb);
3638 extern void ext4_resize_end(struct super_block *sb);
3639 
3640 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3641 					      struct ext4_io_end *io_end)
3642 {
3643 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3644 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3645 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3646 	}
3647 }
3648 
3649 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3650 {
3651 	struct inode *inode = io_end->inode;
3652 
3653 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3654 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3655 		/* Wake up anyone waiting on unwritten extent conversion */
3656 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3657 			wake_up_all(ext4_ioend_wq(inode));
3658 	}
3659 }
3660 
3661 extern const struct iomap_ops ext4_iomap_ops;
3662 extern const struct iomap_ops ext4_iomap_overwrite_ops;
3663 extern const struct iomap_ops ext4_iomap_report_ops;
3664 
3665 static inline int ext4_buffer_uptodate(struct buffer_head *bh)
3666 {
3667 	/*
3668 	 * If the buffer has the write error flag, we have failed
3669 	 * to write out data in the block.  In this  case, we don't
3670 	 * have to read the block because we may read the old data
3671 	 * successfully.
3672 	 */
3673 	if (!buffer_uptodate(bh) && buffer_write_io_error(bh))
3674 		set_buffer_uptodate(bh);
3675 	return buffer_uptodate(bh);
3676 }
3677 
3678 #endif	/* __KERNEL__ */
3679 
3680 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3681 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3682 
3683 #endif	/* _EXT4_H */
3684