xref: /openbmc/linux/fs/ext4/ext4.h (revision 7963e5ac)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  ext4.h
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/include/linux/minix_fs.h
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  */
16 
17 #ifndef _EXT4_H
18 #define _EXT4_H
19 
20 #include <linux/types.h>
21 #include <linux/blkdev.h>
22 #include <linux/magic.h>
23 #include <linux/jbd2.h>
24 #include <linux/quota.h>
25 #include <linux/rwsem.h>
26 #include <linux/rbtree.h>
27 #include <linux/seqlock.h>
28 #include <linux/mutex.h>
29 #include <linux/timer.h>
30 #include <linux/version.h>
31 #include <linux/wait.h>
32 #include <linux/sched/signal.h>
33 #include <linux/blockgroup_lock.h>
34 #include <linux/percpu_counter.h>
35 #include <linux/ratelimit.h>
36 #include <crypto/hash.h>
37 #include <linux/falloc.h>
38 #include <linux/percpu-rwsem.h>
39 #ifdef __KERNEL__
40 #include <linux/compat.h>
41 #endif
42 
43 #include <linux/fscrypt.h>
44 
45 #include <linux/compiler.h>
46 
47 /*
48  * The fourth extended filesystem constants/structures
49  */
50 
51 /*
52  * with AGGRESSIVE_CHECK allocator runs consistency checks over
53  * structures. these checks slow things down a lot
54  */
55 #define AGGRESSIVE_CHECK__
56 
57 /*
58  * with DOUBLE_CHECK defined mballoc creates persistent in-core
59  * bitmaps, maintains and uses them to check for double allocations
60  */
61 #define DOUBLE_CHECK__
62 
63 /*
64  * Define EXT4FS_DEBUG to produce debug messages
65  */
66 #undef EXT4FS_DEBUG
67 
68 /*
69  * Debug code
70  */
71 #ifdef EXT4FS_DEBUG
72 #define ext4_debug(f, a...)						\
73 	do {								\
74 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
75 			__FILE__, __LINE__, __func__);			\
76 		printk(KERN_DEBUG f, ## a);				\
77 	} while (0)
78 #else
79 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
80 #endif
81 
82 /*
83  * Turn on EXT_DEBUG to get lots of info about extents operations.
84  */
85 #define EXT_DEBUG__
86 #ifdef EXT_DEBUG
87 #define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
88 #else
89 #define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
90 #endif
91 
92 /* data type for block offset of block group */
93 typedef int ext4_grpblk_t;
94 
95 /* data type for filesystem-wide blocks number */
96 typedef unsigned long long ext4_fsblk_t;
97 
98 /* data type for file logical block number */
99 typedef __u32 ext4_lblk_t;
100 
101 /* data type for block group number */
102 typedef unsigned int ext4_group_t;
103 
104 enum SHIFT_DIRECTION {
105 	SHIFT_LEFT = 0,
106 	SHIFT_RIGHT,
107 };
108 
109 /*
110  * Flags used in mballoc's allocation_context flags field.
111  *
112  * Also used to show what's going on for debugging purposes when the
113  * flag field is exported via the traceport interface
114  */
115 
116 /* prefer goal again. length */
117 #define EXT4_MB_HINT_MERGE		0x0001
118 /* blocks already reserved */
119 #define EXT4_MB_HINT_RESERVED		0x0002
120 /* metadata is being allocated */
121 #define EXT4_MB_HINT_METADATA		0x0004
122 /* first blocks in the file */
123 #define EXT4_MB_HINT_FIRST		0x0008
124 /* search for the best chunk */
125 #define EXT4_MB_HINT_BEST		0x0010
126 /* data is being allocated */
127 #define EXT4_MB_HINT_DATA		0x0020
128 /* don't preallocate (for tails) */
129 #define EXT4_MB_HINT_NOPREALLOC		0x0040
130 /* allocate for locality group */
131 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
132 /* allocate goal blocks or none */
133 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
134 /* goal is meaningful */
135 #define EXT4_MB_HINT_TRY_GOAL		0x0200
136 /* blocks already pre-reserved by delayed allocation */
137 #define EXT4_MB_DELALLOC_RESERVED	0x0400
138 /* We are doing stream allocation */
139 #define EXT4_MB_STREAM_ALLOC		0x0800
140 /* Use reserved root blocks if needed */
141 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
142 /* Use blocks from reserved pool */
143 #define EXT4_MB_USE_RESERVED		0x2000
144 
145 struct ext4_allocation_request {
146 	/* target inode for block we're allocating */
147 	struct inode *inode;
148 	/* how many blocks we want to allocate */
149 	unsigned int len;
150 	/* logical block in target inode */
151 	ext4_lblk_t logical;
152 	/* the closest logical allocated block to the left */
153 	ext4_lblk_t lleft;
154 	/* the closest logical allocated block to the right */
155 	ext4_lblk_t lright;
156 	/* phys. target (a hint) */
157 	ext4_fsblk_t goal;
158 	/* phys. block for the closest logical allocated block to the left */
159 	ext4_fsblk_t pleft;
160 	/* phys. block for the closest logical allocated block to the right */
161 	ext4_fsblk_t pright;
162 	/* flags. see above EXT4_MB_HINT_* */
163 	unsigned int flags;
164 };
165 
166 /*
167  * Logical to physical block mapping, used by ext4_map_blocks()
168  *
169  * This structure is used to pass requests into ext4_map_blocks() as
170  * well as to store the information returned by ext4_map_blocks().  It
171  * takes less room on the stack than a struct buffer_head.
172  */
173 #define EXT4_MAP_NEW		(1 << BH_New)
174 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
175 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
176 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
177 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
178 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
179 
180 struct ext4_map_blocks {
181 	ext4_fsblk_t m_pblk;
182 	ext4_lblk_t m_lblk;
183 	unsigned int m_len;
184 	unsigned int m_flags;
185 };
186 
187 /*
188  * Flags for ext4_io_end->flags
189  */
190 #define	EXT4_IO_END_UNWRITTEN	0x0001
191 
192 /*
193  * For converting unwritten extents on a work queue. 'handle' is used for
194  * buffered writeback.
195  */
196 typedef struct ext4_io_end {
197 	struct list_head	list;		/* per-file finished IO list */
198 	handle_t		*handle;	/* handle reserved for extent
199 						 * conversion */
200 	struct inode		*inode;		/* file being written to */
201 	struct bio		*bio;		/* Linked list of completed
202 						 * bios covering the extent */
203 	unsigned int		flag;		/* unwritten or not */
204 	atomic_t		count;		/* reference counter */
205 	loff_t			offset;		/* offset in the file */
206 	ssize_t			size;		/* size of the extent */
207 } ext4_io_end_t;
208 
209 struct ext4_io_submit {
210 	struct writeback_control *io_wbc;
211 	struct bio		*io_bio;
212 	ext4_io_end_t		*io_end;
213 	sector_t		io_next_block;
214 };
215 
216 /*
217  * Special inodes numbers
218  */
219 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
220 #define EXT4_ROOT_INO		 2	/* Root inode */
221 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
222 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
223 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
224 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
225 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
226 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
227 
228 /* First non-reserved inode for old ext4 filesystems */
229 #define EXT4_GOOD_OLD_FIRST_INO	11
230 
231 /*
232  * Maximal count of links to a file
233  */
234 #define EXT4_LINK_MAX		65000
235 
236 /*
237  * Macro-instructions used to manage several block sizes
238  */
239 #define EXT4_MIN_BLOCK_SIZE		1024
240 #define	EXT4_MAX_BLOCK_SIZE		65536
241 #define EXT4_MIN_BLOCK_LOG_SIZE		10
242 #define EXT4_MAX_BLOCK_LOG_SIZE		16
243 #define EXT4_MAX_CLUSTER_LOG_SIZE	30
244 #ifdef __KERNEL__
245 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
246 #else
247 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
248 #endif
249 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
250 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
251 					 EXT4_SB(s)->s_cluster_bits)
252 #ifdef __KERNEL__
253 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
254 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
255 #else
256 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
257 #endif
258 #ifdef __KERNEL__
259 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
260 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
261 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
262 #else
263 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
264 				 EXT4_GOOD_OLD_INODE_SIZE : \
265 				 (s)->s_inode_size)
266 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
267 				 EXT4_GOOD_OLD_FIRST_INO : \
268 				 (s)->s_first_ino)
269 #endif
270 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
271 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
272 	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
273 								  blkbits))
274 
275 /* Translate a block number to a cluster number */
276 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
277 /* Translate a cluster number to a block number */
278 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
279 /* Translate # of blks to # of clusters */
280 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
281 				 (sbi)->s_cluster_bits)
282 /* Mask out the low bits to get the starting block of the cluster */
283 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
284 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
285 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
286 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
287 /* Get the cluster offset */
288 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
289 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
290 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
291 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
292 
293 /*
294  * Structure of a blocks group descriptor
295  */
296 struct ext4_group_desc
297 {
298 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
299 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
300 	__le32	bg_inode_table_lo;	/* Inodes table block */
301 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
302 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
303 	__le16	bg_used_dirs_count_lo;	/* Directories count */
304 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
305 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
306 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
307 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
308 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
309 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
310 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
311 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
312 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
313 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
314 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
315 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
316 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
317 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
318 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
319 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
320 	__u32   bg_reserved;
321 };
322 
323 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
324 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
325 	 sizeof(__le16))
326 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
327 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
328 	 sizeof(__le16))
329 
330 /*
331  * Structure of a flex block group info
332  */
333 
334 struct flex_groups {
335 	atomic64_t	free_clusters;
336 	atomic_t	free_inodes;
337 	atomic_t	used_dirs;
338 };
339 
340 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
341 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
342 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
343 
344 /*
345  * Macro-instructions used to manage group descriptors
346  */
347 #define EXT4_MIN_DESC_SIZE		32
348 #define EXT4_MIN_DESC_SIZE_64BIT	64
349 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
350 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
351 #ifdef __KERNEL__
352 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
353 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
354 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
355 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
356 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
357 #else
358 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
359 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
360 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
361 #endif
362 
363 /*
364  * Constants relative to the data blocks
365  */
366 #define	EXT4_NDIR_BLOCKS		12
367 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
368 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
369 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
370 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
371 
372 /*
373  * Inode flags
374  */
375 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
376 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
377 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
378 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
379 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
380 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
381 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
382 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
383 /* Reserved for compression usage... */
384 #define EXT4_DIRTY_FL			0x00000100
385 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
386 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
387 	/* nb: was previously EXT2_ECOMPR_FL */
388 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
389 /* End compression flags --- maybe not all used */
390 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
391 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
392 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
393 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
394 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
395 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
396 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
397 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
398 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
399 #define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
400 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
401 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
402 #define EXT4_CASEFOLD_FL		0x40000000 /* Casefolded file */
403 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
404 
405 #define EXT4_FL_USER_VISIBLE		0x704BDFFF /* User visible flags */
406 #define EXT4_FL_USER_MODIFIABLE		0x604BC0FF /* User modifiable flags */
407 
408 /* Flags we can manipulate with through EXT4_IOC_FSSETXATTR */
409 #define EXT4_FL_XFLAG_VISIBLE		(EXT4_SYNC_FL | \
410 					 EXT4_IMMUTABLE_FL | \
411 					 EXT4_APPEND_FL | \
412 					 EXT4_NODUMP_FL | \
413 					 EXT4_NOATIME_FL | \
414 					 EXT4_PROJINHERIT_FL)
415 
416 /* Flags that should be inherited by new inodes from their parent. */
417 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
418 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
419 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
420 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
421 			   EXT4_PROJINHERIT_FL | EXT4_CASEFOLD_FL)
422 
423 /* Flags that are appropriate for regular files (all but dir-specific ones). */
424 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL | EXT4_CASEFOLD_FL |\
425 			   EXT4_PROJINHERIT_FL))
426 
427 /* Flags that are appropriate for non-directories/regular files. */
428 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
429 
430 /* The only flags that should be swapped */
431 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
432 
433 /* Mask out flags that are inappropriate for the given type of inode. */
434 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
435 {
436 	if (S_ISDIR(mode))
437 		return flags;
438 	else if (S_ISREG(mode))
439 		return flags & EXT4_REG_FLMASK;
440 	else
441 		return flags & EXT4_OTHER_FLMASK;
442 }
443 
444 /*
445  * Inode flags used for atomic set/get
446  */
447 enum {
448 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
449 	EXT4_INODE_UNRM		= 1,	/* Undelete */
450 	EXT4_INODE_COMPR	= 2,	/* Compress file */
451 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
452 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
453 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
454 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
455 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
456 /* Reserved for compression usage... */
457 	EXT4_INODE_DIRTY	= 8,
458 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
459 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
460 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
461 /* End compression flags --- maybe not all used */
462 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
463 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
464 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
465 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
466 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
467 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
468 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
469 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
470 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
471 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
472 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
473 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
474 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
475 };
476 
477 /*
478  * Since it's pretty easy to mix up bit numbers and hex values, we use a
479  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
480  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
481  * any extra space in the compiled kernel image, otherwise, the build will fail.
482  * It's important that these values are the same, since we are using
483  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
484  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
485  * values found in ext2, ext3 and ext4 filesystems, and of course the values
486  * defined in e2fsprogs.
487  *
488  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
489  */
490 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
491 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
492 
493 static inline void ext4_check_flag_values(void)
494 {
495 	CHECK_FLAG_VALUE(SECRM);
496 	CHECK_FLAG_VALUE(UNRM);
497 	CHECK_FLAG_VALUE(COMPR);
498 	CHECK_FLAG_VALUE(SYNC);
499 	CHECK_FLAG_VALUE(IMMUTABLE);
500 	CHECK_FLAG_VALUE(APPEND);
501 	CHECK_FLAG_VALUE(NODUMP);
502 	CHECK_FLAG_VALUE(NOATIME);
503 	CHECK_FLAG_VALUE(DIRTY);
504 	CHECK_FLAG_VALUE(COMPRBLK);
505 	CHECK_FLAG_VALUE(NOCOMPR);
506 	CHECK_FLAG_VALUE(ENCRYPT);
507 	CHECK_FLAG_VALUE(INDEX);
508 	CHECK_FLAG_VALUE(IMAGIC);
509 	CHECK_FLAG_VALUE(JOURNAL_DATA);
510 	CHECK_FLAG_VALUE(NOTAIL);
511 	CHECK_FLAG_VALUE(DIRSYNC);
512 	CHECK_FLAG_VALUE(TOPDIR);
513 	CHECK_FLAG_VALUE(HUGE_FILE);
514 	CHECK_FLAG_VALUE(EXTENTS);
515 	CHECK_FLAG_VALUE(EA_INODE);
516 	CHECK_FLAG_VALUE(EOFBLOCKS);
517 	CHECK_FLAG_VALUE(INLINE_DATA);
518 	CHECK_FLAG_VALUE(PROJINHERIT);
519 	CHECK_FLAG_VALUE(RESERVED);
520 }
521 
522 /* Used to pass group descriptor data when online resize is done */
523 struct ext4_new_group_input {
524 	__u32 group;		/* Group number for this data */
525 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
526 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
527 	__u64 inode_table;	/* Absolute block number of inode table start */
528 	__u32 blocks_count;	/* Total number of blocks in this group */
529 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
530 	__u16 unused;
531 };
532 
533 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
534 struct compat_ext4_new_group_input {
535 	u32 group;
536 	compat_u64 block_bitmap;
537 	compat_u64 inode_bitmap;
538 	compat_u64 inode_table;
539 	u32 blocks_count;
540 	u16 reserved_blocks;
541 	u16 unused;
542 };
543 #endif
544 
545 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
546 struct ext4_new_group_data {
547 	__u32 group;
548 	__u64 block_bitmap;
549 	__u64 inode_bitmap;
550 	__u64 inode_table;
551 	__u32 blocks_count;
552 	__u16 reserved_blocks;
553 	__u16 mdata_blocks;
554 	__u32 free_clusters_count;
555 };
556 
557 /* Indexes used to index group tables in ext4_new_group_data */
558 enum {
559 	BLOCK_BITMAP = 0,	/* block bitmap */
560 	INODE_BITMAP,		/* inode bitmap */
561 	INODE_TABLE,		/* inode tables */
562 	GROUP_TABLE_COUNT,
563 };
564 
565 /*
566  * Flags used by ext4_map_blocks()
567  */
568 	/* Allocate any needed blocks and/or convert an unwritten
569 	   extent to be an initialized ext4 */
570 #define EXT4_GET_BLOCKS_CREATE			0x0001
571 	/* Request the creation of an unwritten extent */
572 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
573 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
574 						 EXT4_GET_BLOCKS_CREATE)
575 	/* Caller is from the delayed allocation writeout path
576 	 * finally doing the actual allocation of delayed blocks */
577 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
578 	/* caller is from the direct IO path, request to creation of an
579 	unwritten extents if not allocated, split the unwritten
580 	extent if blocks has been preallocated already*/
581 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
582 #define EXT4_GET_BLOCKS_CONVERT			0x0010
583 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
584 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
585 	/* Convert extent to initialized after IO complete */
586 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
587 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
588 	/* Eventual metadata allocation (due to growing extent tree)
589 	 * should not fail, so try to use reserved blocks for that.*/
590 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
591 	/* Don't normalize allocation size (used for fallocate) */
592 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
593 	/* Request will not result in inode size update (user for fallocate) */
594 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
595 	/* Convert written extents to unwritten */
596 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
597 	/* Write zeros to newly created written extents */
598 #define EXT4_GET_BLOCKS_ZERO			0x0200
599 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
600 					EXT4_GET_BLOCKS_ZERO)
601 	/* Caller will submit data before dropping transaction handle. This
602 	 * allows jbd2 to avoid submitting data before commit. */
603 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
604 
605 /*
606  * The bit position of these flags must not overlap with any of the
607  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
608  * read_extent_tree_block(), ext4_split_extent_at(),
609  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
610  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
611  * caching the extents when reading from the extent tree while a
612  * truncate or punch hole operation is in progress.
613  */
614 #define EXT4_EX_NOCACHE				0x40000000
615 #define EXT4_EX_FORCE_CACHE			0x20000000
616 
617 /*
618  * Flags used by ext4_free_blocks
619  */
620 #define EXT4_FREE_BLOCKS_METADATA		0x0001
621 #define EXT4_FREE_BLOCKS_FORGET			0x0002
622 #define EXT4_FREE_BLOCKS_VALIDATED		0x0004
623 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE		0x0008
624 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
625 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
626 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
627 
628 /*
629  * ioctl commands
630  */
631 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
632 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
633 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
634 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
635 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
636 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
637 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
638 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
639 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
640 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
641 #define EXT4_IOC_MIGRATE		_IO('f', 9)
642  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
643  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
644 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
645 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
646 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
647 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
648 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
649 #define EXT4_IOC_SET_ENCRYPTION_POLICY	FS_IOC_SET_ENCRYPTION_POLICY
650 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	FS_IOC_GET_ENCRYPTION_PWSALT
651 #define EXT4_IOC_GET_ENCRYPTION_POLICY	FS_IOC_GET_ENCRYPTION_POLICY
652 /* ioctl codes 19--39 are reserved for fscrypt */
653 #define EXT4_IOC_CLEAR_ES_CACHE		_IO('f', 40)
654 #define EXT4_IOC_GETSTATE		_IOW('f', 41, __u32)
655 #define EXT4_IOC_GET_ES_CACHE		_IOWR('f', 42, struct fiemap)
656 
657 #define EXT4_IOC_FSGETXATTR		FS_IOC_FSGETXATTR
658 #define EXT4_IOC_FSSETXATTR		FS_IOC_FSSETXATTR
659 
660 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
661 
662 /*
663  * Flags for going down operation
664  */
665 #define EXT4_GOING_FLAGS_DEFAULT		0x0	/* going down */
666 #define EXT4_GOING_FLAGS_LOGFLUSH		0x1	/* flush log but not data */
667 #define EXT4_GOING_FLAGS_NOLOGFLUSH		0x2	/* don't flush log nor data */
668 
669 /*
670  * Flags returned by EXT4_IOC_GETSTATE
671  *
672  * We only expose to userspace a subset of the state flags in
673  * i_state_flags
674  */
675 #define EXT4_STATE_FLAG_EXT_PRECACHED	0x00000001
676 #define EXT4_STATE_FLAG_NEW		0x00000002
677 #define EXT4_STATE_FLAG_NEWENTRY	0x00000004
678 #define EXT4_STATE_FLAG_DA_ALLOC_CLOSE	0x00000008
679 
680 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
681 /*
682  * ioctl commands in 32 bit emulation
683  */
684 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
685 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
686 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
687 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
688 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
689 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
690 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
691 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
692 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
693 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
694 #endif
695 
696 /*
697  * Returned by EXT4_IOC_GET_ES_CACHE as an additional possible flag.
698  * It indicates that the entry in extent status cache is for a hole.
699  */
700 #define EXT4_FIEMAP_EXTENT_HOLE		0x08000000
701 
702 /* Max physical block we can address w/o extents */
703 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
704 
705 /* Max logical block we can support */
706 #define EXT4_MAX_LOGICAL_BLOCK		0xFFFFFFFF
707 
708 /*
709  * Structure of an inode on the disk
710  */
711 struct ext4_inode {
712 	__le16	i_mode;		/* File mode */
713 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
714 	__le32	i_size_lo;	/* Size in bytes */
715 	__le32	i_atime;	/* Access time */
716 	__le32	i_ctime;	/* Inode Change time */
717 	__le32	i_mtime;	/* Modification time */
718 	__le32	i_dtime;	/* Deletion Time */
719 	__le16	i_gid;		/* Low 16 bits of Group Id */
720 	__le16	i_links_count;	/* Links count */
721 	__le32	i_blocks_lo;	/* Blocks count */
722 	__le32	i_flags;	/* File flags */
723 	union {
724 		struct {
725 			__le32  l_i_version;
726 		} linux1;
727 		struct {
728 			__u32  h_i_translator;
729 		} hurd1;
730 		struct {
731 			__u32  m_i_reserved1;
732 		} masix1;
733 	} osd1;				/* OS dependent 1 */
734 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
735 	__le32	i_generation;	/* File version (for NFS) */
736 	__le32	i_file_acl_lo;	/* File ACL */
737 	__le32	i_size_high;
738 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
739 	union {
740 		struct {
741 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
742 			__le16	l_i_file_acl_high;
743 			__le16	l_i_uid_high;	/* these 2 fields */
744 			__le16	l_i_gid_high;	/* were reserved2[0] */
745 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
746 			__le16	l_i_reserved;
747 		} linux2;
748 		struct {
749 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
750 			__u16	h_i_mode_high;
751 			__u16	h_i_uid_high;
752 			__u16	h_i_gid_high;
753 			__u32	h_i_author;
754 		} hurd2;
755 		struct {
756 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
757 			__le16	m_i_file_acl_high;
758 			__u32	m_i_reserved2[2];
759 		} masix2;
760 	} osd2;				/* OS dependent 2 */
761 	__le16	i_extra_isize;
762 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
763 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
764 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
765 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
766 	__le32  i_crtime;       /* File Creation time */
767 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
768 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
769 	__le32	i_projid;	/* Project ID */
770 };
771 
772 struct move_extent {
773 	__u32 reserved;		/* should be zero */
774 	__u32 donor_fd;		/* donor file descriptor */
775 	__u64 orig_start;	/* logical start offset in block for orig */
776 	__u64 donor_start;	/* logical start offset in block for donor */
777 	__u64 len;		/* block length to be moved */
778 	__u64 moved_len;	/* moved block length */
779 };
780 
781 #define EXT4_EPOCH_BITS 2
782 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
783 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
784 
785 /*
786  * Extended fields will fit into an inode if the filesystem was formatted
787  * with large inodes (-I 256 or larger) and there are not currently any EAs
788  * consuming all of the available space. For new inodes we always reserve
789  * enough space for the kernel's known extended fields, but for inodes
790  * created with an old kernel this might not have been the case. None of
791  * the extended inode fields is critical for correct filesystem operation.
792  * This macro checks if a certain field fits in the inode. Note that
793  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
794  */
795 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
796 	((offsetof(typeof(*ext4_inode), field) +	\
797 	  sizeof((ext4_inode)->field))			\
798 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
799 	    (einode)->i_extra_isize))			\
800 
801 /*
802  * We use an encoding that preserves the times for extra epoch "00":
803  *
804  * extra  msb of                         adjust for signed
805  * epoch  32-bit                         32-bit tv_sec to
806  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
807  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
808  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
809  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
810  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
811  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
812  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
813  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
814  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
815  *
816  * Note that previous versions of the kernel on 64-bit systems would
817  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
818  * 1970.  e2fsck will correct this, assuming that it is run on the
819  * affected filesystem before 2242.
820  */
821 
822 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
823 {
824 	u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
825 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
826 }
827 
828 static inline void ext4_decode_extra_time(struct timespec64 *time,
829 					  __le32 extra)
830 {
831 	if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK)))
832 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
833 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
834 }
835 
836 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)				\
837 do {										\
838 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);		\
839 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
840 		(raw_inode)->xtime ## _extra =					\
841 				ext4_encode_extra_time(&(inode)->xtime);	\
842 		}								\
843 } while (0)
844 
845 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
846 do {									       \
847 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
848 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
849 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
850 		(raw_inode)->xtime ## _extra =				       \
851 				ext4_encode_extra_time(&(einode)->xtime);      \
852 } while (0)
853 
854 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)				\
855 do {										\
856 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);	\
857 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {	\
858 		ext4_decode_extra_time(&(inode)->xtime,				\
859 				       raw_inode->xtime ## _extra);		\
860 		}								\
861 	else									\
862 		(inode)->xtime.tv_nsec = 0;					\
863 } while (0)
864 
865 
866 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
867 do {									       \
868 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
869 		(einode)->xtime.tv_sec = 				       \
870 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
871 	else								       \
872 		(einode)->xtime.tv_sec = 0;				       \
873 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
874 		ext4_decode_extra_time(&(einode)->xtime,		       \
875 				       raw_inode->xtime ## _extra);	       \
876 	else								       \
877 		(einode)->xtime.tv_nsec = 0;				       \
878 } while (0)
879 
880 #define i_disk_version osd1.linux1.l_i_version
881 
882 #if defined(__KERNEL__) || defined(__linux__)
883 #define i_reserved1	osd1.linux1.l_i_reserved1
884 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
885 #define i_blocks_high	osd2.linux2.l_i_blocks_high
886 #define i_uid_low	i_uid
887 #define i_gid_low	i_gid
888 #define i_uid_high	osd2.linux2.l_i_uid_high
889 #define i_gid_high	osd2.linux2.l_i_gid_high
890 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
891 
892 #elif defined(__GNU__)
893 
894 #define i_translator	osd1.hurd1.h_i_translator
895 #define i_uid_high	osd2.hurd2.h_i_uid_high
896 #define i_gid_high	osd2.hurd2.h_i_gid_high
897 #define i_author	osd2.hurd2.h_i_author
898 
899 #elif defined(__masix__)
900 
901 #define i_reserved1	osd1.masix1.m_i_reserved1
902 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
903 #define i_reserved2	osd2.masix2.m_i_reserved2
904 
905 #endif /* defined(__KERNEL__) || defined(__linux__) */
906 
907 #include "extents_status.h"
908 
909 /*
910  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
911  *
912  * These are needed to avoid lockdep false positives when we need to
913  * allocate blocks to the quota inode during ext4_map_blocks(), while
914  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
915  * do quota tracking for the quota inode, this avoids deadlock (as
916  * well as infinite recursion, since it isn't turtles all the way
917  * down...)
918  *
919  *  I_DATA_SEM_NORMAL - Used for most inodes
920  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
921  *			  where the second inode has larger inode number
922  *			  than the first
923  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
924  */
925 enum {
926 	I_DATA_SEM_NORMAL = 0,
927 	I_DATA_SEM_OTHER,
928 	I_DATA_SEM_QUOTA,
929 };
930 
931 
932 /*
933  * fourth extended file system inode data in memory
934  */
935 struct ext4_inode_info {
936 	__le32	i_data[15];	/* unconverted */
937 	__u32	i_dtime;
938 	ext4_fsblk_t	i_file_acl;
939 
940 	/*
941 	 * i_block_group is the number of the block group which contains
942 	 * this file's inode.  Constant across the lifetime of the inode,
943 	 * it is used for making block allocation decisions - we try to
944 	 * place a file's data blocks near its inode block, and new inodes
945 	 * near to their parent directory's inode.
946 	 */
947 	ext4_group_t	i_block_group;
948 	ext4_lblk_t	i_dir_start_lookup;
949 #if (BITS_PER_LONG < 64)
950 	unsigned long	i_state_flags;		/* Dynamic state flags */
951 #endif
952 	unsigned long	i_flags;
953 
954 	/*
955 	 * Extended attributes can be read independently of the main file
956 	 * data. Taking i_mutex even when reading would cause contention
957 	 * between readers of EAs and writers of regular file data, so
958 	 * instead we synchronize on xattr_sem when reading or changing
959 	 * EAs.
960 	 */
961 	struct rw_semaphore xattr_sem;
962 
963 	struct list_head i_orphan;	/* unlinked but open inodes */
964 
965 	/*
966 	 * i_disksize keeps track of what the inode size is ON DISK, not
967 	 * in memory.  During truncate, i_size is set to the new size by
968 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
969 	 * set i_disksize to 0 until the truncate is actually under way.
970 	 *
971 	 * The intent is that i_disksize always represents the blocks which
972 	 * are used by this file.  This allows recovery to restart truncate
973 	 * on orphans if we crash during truncate.  We actually write i_disksize
974 	 * into the on-disk inode when writing inodes out, instead of i_size.
975 	 *
976 	 * The only time when i_disksize and i_size may be different is when
977 	 * a truncate is in progress.  The only things which change i_disksize
978 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
979 	 */
980 	loff_t	i_disksize;
981 
982 	/*
983 	 * i_data_sem is for serialising ext4_truncate() against
984 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
985 	 * data tree are chopped off during truncate. We can't do that in
986 	 * ext4 because whenever we perform intermediate commits during
987 	 * truncate, the inode and all the metadata blocks *must* be in a
988 	 * consistent state which allows truncation of the orphans to restart
989 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
990 	 * by other means, so we have i_data_sem.
991 	 */
992 	struct rw_semaphore i_data_sem;
993 	/*
994 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
995 	 * operations. We have to make sure that new page cannot be faulted in
996 	 * a section of the inode that is being punched. We cannot easily use
997 	 * i_data_sem for this since we need protection for the whole punch
998 	 * operation and i_data_sem ranks below transaction start so we have
999 	 * to occasionally drop it.
1000 	 */
1001 	struct rw_semaphore i_mmap_sem;
1002 	struct inode vfs_inode;
1003 	struct jbd2_inode *jinode;
1004 
1005 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
1006 
1007 	/*
1008 	 * File creation time. Its function is same as that of
1009 	 * struct timespec64 i_{a,c,m}time in the generic inode.
1010 	 */
1011 	struct timespec64 i_crtime;
1012 
1013 	/* mballoc */
1014 	struct list_head i_prealloc_list;
1015 	spinlock_t i_prealloc_lock;
1016 
1017 	/* extents status tree */
1018 	struct ext4_es_tree i_es_tree;
1019 	rwlock_t i_es_lock;
1020 	struct list_head i_es_list;
1021 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1022 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1023 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1024 					   extents to shrink. Protected by
1025 					   i_es_lock  */
1026 
1027 	/* ialloc */
1028 	ext4_group_t	i_last_alloc_group;
1029 
1030 	/* allocation reservation info for delalloc */
1031 	/* In case of bigalloc, this refer to clusters rather than blocks */
1032 	unsigned int i_reserved_data_blocks;
1033 	ext4_lblk_t i_da_metadata_calc_last_lblock;
1034 	int i_da_metadata_calc_len;
1035 
1036 	/* pending cluster reservations for bigalloc file systems */
1037 	struct ext4_pending_tree i_pending_tree;
1038 
1039 	/* on-disk additional length */
1040 	__u16 i_extra_isize;
1041 
1042 	/* Indicate the inline data space. */
1043 	u16 i_inline_off;
1044 	u16 i_inline_size;
1045 
1046 #ifdef CONFIG_QUOTA
1047 	/* quota space reservation, managed internally by quota code */
1048 	qsize_t i_reserved_quota;
1049 #endif
1050 
1051 	/* Lock protecting lists below */
1052 	spinlock_t i_completed_io_lock;
1053 	/*
1054 	 * Completed IOs that need unwritten extents handling and have
1055 	 * transaction reserved
1056 	 */
1057 	struct list_head i_rsv_conversion_list;
1058 	struct work_struct i_rsv_conversion_work;
1059 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1060 
1061 	spinlock_t i_block_reservation_lock;
1062 
1063 	/*
1064 	 * Transactions that contain inode's metadata needed to complete
1065 	 * fsync and fdatasync, respectively.
1066 	 */
1067 	tid_t i_sync_tid;
1068 	tid_t i_datasync_tid;
1069 
1070 #ifdef CONFIG_QUOTA
1071 	struct dquot *i_dquot[MAXQUOTAS];
1072 #endif
1073 
1074 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1075 	__u32 i_csum_seed;
1076 
1077 	kprojid_t i_projid;
1078 };
1079 
1080 /*
1081  * File system states
1082  */
1083 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1084 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1085 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1086 
1087 /*
1088  * Misc. filesystem flags
1089  */
1090 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1091 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1092 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1093 
1094 /*
1095  * Mount flags set via mount options or defaults
1096  */
1097 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1098 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1099 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1100 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1101 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1102 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1103 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1104 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1105 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1106 #ifdef CONFIG_FS_DAX
1107 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
1108 #else
1109 #define EXT4_MOUNT_DAX			0
1110 #endif
1111 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1112 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1113 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1114 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1115 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1116 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1117 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1118 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1119 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1120 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1121 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1122 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1123 						 * enable enforcement for hidden
1124 						 * quota files */
1125 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1126 						  * enforcement for hidden quota
1127 						  * files */
1128 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1129 						  * enforcement */
1130 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1131 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1132 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1133 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
1134 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1135 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1136 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1137 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1138 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1139 
1140 /*
1141  * Mount flags set either automatically (could not be set by mount option)
1142  * based on per file system feature or property or in special cases such as
1143  * distinguishing between explicit mount option definition and default.
1144  */
1145 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1146 						      specified delalloc */
1147 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1148 						      size of blocksize * 8
1149 						      blocks */
1150 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1151 						      file systems */
1152 
1153 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1154 						specified journal checksum */
1155 
1156 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1157 						~EXT4_MOUNT_##opt
1158 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1159 						EXT4_MOUNT_##opt
1160 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1161 					 EXT4_MOUNT_##opt)
1162 
1163 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1164 						~EXT4_MOUNT2_##opt
1165 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1166 						EXT4_MOUNT2_##opt
1167 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1168 					 EXT4_MOUNT2_##opt)
1169 
1170 #define ext4_test_and_set_bit		__test_and_set_bit_le
1171 #define ext4_set_bit			__set_bit_le
1172 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1173 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1174 #define ext4_clear_bit			__clear_bit_le
1175 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1176 #define ext4_test_bit			test_bit_le
1177 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1178 #define ext4_find_next_bit		find_next_bit_le
1179 
1180 extern void ext4_set_bits(void *bm, int cur, int len);
1181 
1182 /*
1183  * Maximal mount counts between two filesystem checks
1184  */
1185 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1186 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1187 
1188 /*
1189  * Behaviour when detecting errors
1190  */
1191 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1192 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1193 #define EXT4_ERRORS_PANIC		3	/* Panic */
1194 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1195 
1196 /* Metadata checksum algorithm codes */
1197 #define EXT4_CRC32C_CHKSUM		1
1198 
1199 /*
1200  * Structure of the super block
1201  */
1202 struct ext4_super_block {
1203 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1204 	__le32	s_blocks_count_lo;	/* Blocks count */
1205 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1206 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1207 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1208 	__le32	s_first_data_block;	/* First Data Block */
1209 	__le32	s_log_block_size;	/* Block size */
1210 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1211 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1212 	__le32	s_clusters_per_group;	/* # Clusters per group */
1213 	__le32	s_inodes_per_group;	/* # Inodes per group */
1214 	__le32	s_mtime;		/* Mount time */
1215 /*30*/	__le32	s_wtime;		/* Write time */
1216 	__le16	s_mnt_count;		/* Mount count */
1217 	__le16	s_max_mnt_count;	/* Maximal mount count */
1218 	__le16	s_magic;		/* Magic signature */
1219 	__le16	s_state;		/* File system state */
1220 	__le16	s_errors;		/* Behaviour when detecting errors */
1221 	__le16	s_minor_rev_level;	/* minor revision level */
1222 /*40*/	__le32	s_lastcheck;		/* time of last check */
1223 	__le32	s_checkinterval;	/* max. time between checks */
1224 	__le32	s_creator_os;		/* OS */
1225 	__le32	s_rev_level;		/* Revision level */
1226 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1227 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1228 	/*
1229 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1230 	 *
1231 	 * Note: the difference between the compatible feature set and
1232 	 * the incompatible feature set is that if there is a bit set
1233 	 * in the incompatible feature set that the kernel doesn't
1234 	 * know about, it should refuse to mount the filesystem.
1235 	 *
1236 	 * e2fsck's requirements are more strict; if it doesn't know
1237 	 * about a feature in either the compatible or incompatible
1238 	 * feature set, it must abort and not try to meddle with
1239 	 * things it doesn't understand...
1240 	 */
1241 	__le32	s_first_ino;		/* First non-reserved inode */
1242 	__le16  s_inode_size;		/* size of inode structure */
1243 	__le16	s_block_group_nr;	/* block group # of this superblock */
1244 	__le32	s_feature_compat;	/* compatible feature set */
1245 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1246 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1247 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1248 /*78*/	char	s_volume_name[16];	/* volume name */
1249 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
1250 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1251 	/*
1252 	 * Performance hints.  Directory preallocation should only
1253 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1254 	 */
1255 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1256 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1257 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1258 	/*
1259 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1260 	 */
1261 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1262 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1263 	__le32	s_journal_dev;		/* device number of journal file */
1264 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1265 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1266 	__u8	s_def_hash_version;	/* Default hash version to use */
1267 	__u8	s_jnl_backup_type;
1268 	__le16  s_desc_size;		/* size of group descriptor */
1269 /*100*/	__le32	s_default_mount_opts;
1270 	__le32	s_first_meta_bg;	/* First metablock block group */
1271 	__le32	s_mkfs_time;		/* When the filesystem was created */
1272 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1273 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1274 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1275 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1276 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1277 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1278 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1279 	__le32	s_flags;		/* Miscellaneous flags */
1280 	__le16  s_raid_stride;		/* RAID stride */
1281 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1282 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1283 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1284 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1285 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1286 	__u8	s_encryption_level;	/* versioning level for encryption */
1287 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1288 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1289 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1290 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1291 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1292 					      snapshot's future use */
1293 	__le32	s_snapshot_list;	/* inode number of the head of the
1294 					   on-disk snapshot list */
1295 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1296 	__le32	s_error_count;		/* number of fs errors */
1297 	__le32	s_first_error_time;	/* first time an error happened */
1298 	__le32	s_first_error_ino;	/* inode involved in first error */
1299 	__le64	s_first_error_block;	/* block involved of first error */
1300 	__u8	s_first_error_func[32] __nonstring;	/* function where the error happened */
1301 	__le32	s_first_error_line;	/* line number where error happened */
1302 	__le32	s_last_error_time;	/* most recent time of an error */
1303 	__le32	s_last_error_ino;	/* inode involved in last error */
1304 	__le32	s_last_error_line;	/* line number where error happened */
1305 	__le64	s_last_error_block;	/* block involved of last error */
1306 	__u8	s_last_error_func[32] __nonstring;	/* function where the error happened */
1307 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1308 	__u8	s_mount_opts[64];
1309 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1310 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1311 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1312 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1313 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1314 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1315 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1316 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1317 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1318 	__u8	s_wtime_hi;
1319 	__u8	s_mtime_hi;
1320 	__u8	s_mkfs_time_hi;
1321 	__u8	s_lastcheck_hi;
1322 	__u8	s_first_error_time_hi;
1323 	__u8	s_last_error_time_hi;
1324 	__u8	s_pad[2];
1325 	__le16  s_encoding;		/* Filename charset encoding */
1326 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
1327 	__le32	s_reserved[95];		/* Padding to the end of the block */
1328 	__le32	s_checksum;		/* crc32c(superblock) */
1329 };
1330 
1331 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1332 
1333 #ifdef __KERNEL__
1334 
1335 /*
1336  * run-time mount flags
1337  */
1338 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1339 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1340 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1341 
1342 #ifdef CONFIG_FS_ENCRYPTION
1343 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1344 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1345 #else
1346 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1347 #endif
1348 
1349 /* Number of quota types we support */
1350 #define EXT4_MAXQUOTAS 3
1351 
1352 #define EXT4_ENC_UTF8_12_1	1
1353 
1354 /*
1355  * Flags for ext4_sb_info.s_encoding_flags.
1356  */
1357 #define EXT4_ENC_STRICT_MODE_FL	(1 << 0)
1358 
1359 #define ext4_has_strict_mode(sbi) \
1360 	(sbi->s_encoding_flags & EXT4_ENC_STRICT_MODE_FL)
1361 
1362 /*
1363  * fourth extended-fs super-block data in memory
1364  */
1365 struct ext4_sb_info {
1366 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1367 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1368 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1369 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1370 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1371 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1372 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1373 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1374 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1375 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1376 	unsigned long s_overhead;  /* # of fs overhead clusters */
1377 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1378 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1379 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1380 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1381 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1382 	struct buffer_head **s_group_desc;
1383 	unsigned int s_mount_opt;
1384 	unsigned int s_mount_opt2;
1385 	unsigned int s_mount_flags;
1386 	unsigned int s_def_mount_opt;
1387 	ext4_fsblk_t s_sb_block;
1388 	atomic64_t s_resv_clusters;
1389 	kuid_t s_resuid;
1390 	kgid_t s_resgid;
1391 	unsigned short s_mount_state;
1392 	unsigned short s_pad;
1393 	int s_addr_per_block_bits;
1394 	int s_desc_per_block_bits;
1395 	int s_inode_size;
1396 	int s_first_ino;
1397 	unsigned int s_inode_readahead_blks;
1398 	unsigned int s_inode_goal;
1399 	u32 s_hash_seed[4];
1400 	int s_def_hash_version;
1401 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1402 	struct percpu_counter s_freeclusters_counter;
1403 	struct percpu_counter s_freeinodes_counter;
1404 	struct percpu_counter s_dirs_counter;
1405 	struct percpu_counter s_dirtyclusters_counter;
1406 	struct blockgroup_lock *s_blockgroup_lock;
1407 	struct proc_dir_entry *s_proc;
1408 	struct kobject s_kobj;
1409 	struct completion s_kobj_unregister;
1410 	struct super_block *s_sb;
1411 #ifdef CONFIG_UNICODE
1412 	struct unicode_map *s_encoding;
1413 	__u16 s_encoding_flags;
1414 #endif
1415 
1416 	/* Journaling */
1417 	struct journal_s *s_journal;
1418 	struct list_head s_orphan;
1419 	struct mutex s_orphan_lock;
1420 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1421 	unsigned long s_commit_interval;
1422 	u32 s_max_batch_time;
1423 	u32 s_min_batch_time;
1424 	struct block_device *journal_bdev;
1425 #ifdef CONFIG_QUOTA
1426 	/* Names of quota files with journalled quota */
1427 	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1428 	int s_jquota_fmt;			/* Format of quota to use */
1429 #endif
1430 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1431 	struct rb_root system_blks;
1432 
1433 #ifdef EXTENTS_STATS
1434 	/* ext4 extents stats */
1435 	unsigned long s_ext_min;
1436 	unsigned long s_ext_max;
1437 	unsigned long s_depth_max;
1438 	spinlock_t s_ext_stats_lock;
1439 	unsigned long s_ext_blocks;
1440 	unsigned long s_ext_extents;
1441 #endif
1442 
1443 	/* for buddy allocator */
1444 	struct ext4_group_info ***s_group_info;
1445 	struct inode *s_buddy_cache;
1446 	spinlock_t s_md_lock;
1447 	unsigned short *s_mb_offsets;
1448 	unsigned int *s_mb_maxs;
1449 	unsigned int s_group_info_size;
1450 	unsigned int s_mb_free_pending;
1451 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1452 						   after commit completed */
1453 
1454 	/* tunables */
1455 	unsigned long s_stripe;
1456 	unsigned int s_mb_stream_request;
1457 	unsigned int s_mb_max_to_scan;
1458 	unsigned int s_mb_min_to_scan;
1459 	unsigned int s_mb_stats;
1460 	unsigned int s_mb_order2_reqs;
1461 	unsigned int s_mb_group_prealloc;
1462 	unsigned int s_max_dir_size_kb;
1463 	/* where last allocation was done - for stream allocation */
1464 	unsigned long s_mb_last_group;
1465 	unsigned long s_mb_last_start;
1466 
1467 	/* stats for buddy allocator */
1468 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1469 	atomic_t s_bal_success;	/* we found long enough chunks */
1470 	atomic_t s_bal_allocated;	/* in blocks */
1471 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1472 	atomic_t s_bal_goals;	/* goal hits */
1473 	atomic_t s_bal_breaks;	/* too long searches */
1474 	atomic_t s_bal_2orders;	/* 2^order hits */
1475 	spinlock_t s_bal_lock;
1476 	unsigned long s_mb_buddies_generated;
1477 	unsigned long long s_mb_generation_time;
1478 	atomic_t s_mb_lost_chunks;
1479 	atomic_t s_mb_preallocated;
1480 	atomic_t s_mb_discarded;
1481 	atomic_t s_lock_busy;
1482 
1483 	/* locality groups */
1484 	struct ext4_locality_group __percpu *s_locality_groups;
1485 
1486 	/* for write statistics */
1487 	unsigned long s_sectors_written_start;
1488 	u64 s_kbytes_written;
1489 
1490 	/* the size of zero-out chunk */
1491 	unsigned int s_extent_max_zeroout_kb;
1492 
1493 	unsigned int s_log_groups_per_flex;
1494 	struct flex_groups *s_flex_groups;
1495 	ext4_group_t s_flex_groups_allocated;
1496 
1497 	/* workqueue for reserved extent conversions (buffered io) */
1498 	struct workqueue_struct *rsv_conversion_wq;
1499 
1500 	/* timer for periodic error stats printing */
1501 	struct timer_list s_err_report;
1502 
1503 	/* Lazy inode table initialization info */
1504 	struct ext4_li_request *s_li_request;
1505 	/* Wait multiplier for lazy initialization thread */
1506 	unsigned int s_li_wait_mult;
1507 
1508 	/* Kernel thread for multiple mount protection */
1509 	struct task_struct *s_mmp_tsk;
1510 
1511 	/* record the last minlen when FITRIM is called. */
1512 	atomic_t s_last_trim_minblks;
1513 
1514 	/* Reference to checksum algorithm driver via cryptoapi */
1515 	struct crypto_shash *s_chksum_driver;
1516 
1517 	/* Precomputed FS UUID checksum for seeding other checksums */
1518 	__u32 s_csum_seed;
1519 
1520 	/* Reclaim extents from extent status tree */
1521 	struct shrinker s_es_shrinker;
1522 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1523 	long s_es_nr_inode;
1524 	struct ext4_es_stats s_es_stats;
1525 	struct mb_cache *s_ea_block_cache;
1526 	struct mb_cache *s_ea_inode_cache;
1527 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1528 
1529 	/* Ratelimit ext4 messages. */
1530 	struct ratelimit_state s_err_ratelimit_state;
1531 	struct ratelimit_state s_warning_ratelimit_state;
1532 	struct ratelimit_state s_msg_ratelimit_state;
1533 
1534 	/* Barrier between changing inodes' journal flags and writepages ops. */
1535 	struct percpu_rw_semaphore s_journal_flag_rwsem;
1536 	struct dax_device *s_daxdev;
1537 };
1538 
1539 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1540 {
1541 	return sb->s_fs_info;
1542 }
1543 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1544 {
1545 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1546 }
1547 
1548 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1549 {
1550 	return ino == EXT4_ROOT_INO ||
1551 		(ino >= EXT4_FIRST_INO(sb) &&
1552 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1553 }
1554 
1555 /*
1556  * Inode dynamic state flags
1557  */
1558 enum {
1559 	EXT4_STATE_JDATA,		/* journaled data exists */
1560 	EXT4_STATE_NEW,			/* inode is newly created */
1561 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1562 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1563 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1564 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1565 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1566 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1567 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1568 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1569 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1570 };
1571 
1572 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1573 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1574 {									\
1575 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1576 }									\
1577 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1578 {									\
1579 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1580 }									\
1581 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1582 {									\
1583 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1584 }
1585 
1586 /* Add these declarations here only so that these functions can be
1587  * found by name.  Otherwise, they are very hard to locate. */
1588 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1589 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1590 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1591 EXT4_INODE_BIT_FNS(flag, flags, 0)
1592 
1593 /* Add these declarations here only so that these functions can be
1594  * found by name.  Otherwise, they are very hard to locate. */
1595 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1596 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1597 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1598 #if (BITS_PER_LONG < 64)
1599 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1600 
1601 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1602 {
1603 	(ei)->i_state_flags = 0;
1604 }
1605 #else
1606 EXT4_INODE_BIT_FNS(state, flags, 32)
1607 
1608 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1609 {
1610 	/* We depend on the fact that callers will set i_flags */
1611 }
1612 #endif
1613 #else
1614 /* Assume that user mode programs are passing in an ext4fs superblock, not
1615  * a kernel struct super_block.  This will allow us to call the feature-test
1616  * macros from user land. */
1617 #define EXT4_SB(sb)	(sb)
1618 #endif
1619 
1620 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1621 
1622 /*
1623  * Codes for operating systems
1624  */
1625 #define EXT4_OS_LINUX		0
1626 #define EXT4_OS_HURD		1
1627 #define EXT4_OS_MASIX		2
1628 #define EXT4_OS_FREEBSD		3
1629 #define EXT4_OS_LITES		4
1630 
1631 /*
1632  * Revision levels
1633  */
1634 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1635 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1636 
1637 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1638 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1639 
1640 #define EXT4_GOOD_OLD_INODE_SIZE 128
1641 
1642 /*
1643  * Feature set definitions
1644  */
1645 
1646 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1647 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1648 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1649 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1650 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1651 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1652 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1653 
1654 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1655 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1656 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1657 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1658 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1659 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1660 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1661 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1662 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1663 /*
1664  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1665  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1666  * all other data structures' checksums.  However, the METADATA_CSUM and
1667  * GDT_CSUM bits are mutually exclusive.
1668  */
1669 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1670 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1671 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1672 
1673 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1674 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1675 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1676 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1677 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1678 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1679 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1680 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1681 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1682 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1683 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1684 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1685 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1686 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1687 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1688 #define EXT4_FEATURE_INCOMPAT_CASEFOLD		0x20000
1689 
1690 extern void ext4_update_dynamic_rev(struct super_block *sb);
1691 
1692 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1693 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1694 { \
1695 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1696 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1697 } \
1698 static inline void ext4_set_feature_##name(struct super_block *sb) \
1699 { \
1700 	ext4_update_dynamic_rev(sb); \
1701 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1702 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1703 } \
1704 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1705 { \
1706 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1707 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1708 }
1709 
1710 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1711 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1712 { \
1713 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1714 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1715 } \
1716 static inline void ext4_set_feature_##name(struct super_block *sb) \
1717 { \
1718 	ext4_update_dynamic_rev(sb); \
1719 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1720 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1721 } \
1722 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1723 { \
1724 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1725 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1726 }
1727 
1728 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1729 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1730 { \
1731 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1732 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1733 } \
1734 static inline void ext4_set_feature_##name(struct super_block *sb) \
1735 { \
1736 	ext4_update_dynamic_rev(sb); \
1737 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
1738 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1739 } \
1740 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1741 { \
1742 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1743 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1744 }
1745 
1746 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1747 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1748 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1749 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1750 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1751 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1752 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1753 
1754 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1755 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1756 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1757 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1758 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1759 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1760 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1761 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1762 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1763 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1764 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1765 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1766 
1767 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1768 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
1769 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
1770 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
1771 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
1772 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
1773 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
1774 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
1775 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
1776 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
1777 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
1778 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
1779 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
1780 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
1781 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
1782 EXT4_FEATURE_INCOMPAT_FUNCS(casefold,		CASEFOLD)
1783 
1784 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1785 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1786 					 EXT4_FEATURE_INCOMPAT_META_BG)
1787 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1788 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1789 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1790 
1791 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1792 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1793 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1794 					 EXT4_FEATURE_INCOMPAT_META_BG)
1795 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1796 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1797 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1798 
1799 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1800 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1801 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1802 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1803 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1804 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1805 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1806 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
1807 					 EXT4_FEATURE_INCOMPAT_MMP | \
1808 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1809 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1810 					 EXT4_FEATURE_INCOMPAT_CASEFOLD | \
1811 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
1812 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
1813 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1814 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1815 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1816 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1817 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1818 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1819 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1820 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1821 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1822 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
1823 					 EXT4_FEATURE_RO_COMPAT_PROJECT)
1824 
1825 #define EXTN_FEATURE_FUNCS(ver) \
1826 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1827 { \
1828 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1829 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1830 } \
1831 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1832 { \
1833 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1834 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1835 } \
1836 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1837 { \
1838 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1839 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1840 }
1841 
1842 EXTN_FEATURE_FUNCS(2)
1843 EXTN_FEATURE_FUNCS(3)
1844 EXTN_FEATURE_FUNCS(4)
1845 
1846 static inline bool ext4_has_compat_features(struct super_block *sb)
1847 {
1848 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1849 }
1850 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1851 {
1852 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1853 }
1854 static inline bool ext4_has_incompat_features(struct super_block *sb)
1855 {
1856 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
1857 }
1858 
1859 /*
1860  * Superblock flags
1861  */
1862 #define EXT4_FLAGS_RESIZING	0
1863 #define EXT4_FLAGS_SHUTDOWN	1
1864 
1865 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
1866 {
1867 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
1868 }
1869 
1870 
1871 /*
1872  * Default values for user and/or group using reserved blocks
1873  */
1874 #define	EXT4_DEF_RESUID		0
1875 #define	EXT4_DEF_RESGID		0
1876 
1877 /*
1878  * Default project ID
1879  */
1880 #define	EXT4_DEF_PROJID		0
1881 
1882 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1883 
1884 /*
1885  * Default mount options
1886  */
1887 #define EXT4_DEFM_DEBUG		0x0001
1888 #define EXT4_DEFM_BSDGROUPS	0x0002
1889 #define EXT4_DEFM_XATTR_USER	0x0004
1890 #define EXT4_DEFM_ACL		0x0008
1891 #define EXT4_DEFM_UID16		0x0010
1892 #define EXT4_DEFM_JMODE		0x0060
1893 #define EXT4_DEFM_JMODE_DATA	0x0020
1894 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1895 #define EXT4_DEFM_JMODE_WBACK	0x0060
1896 #define EXT4_DEFM_NOBARRIER	0x0100
1897 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1898 #define EXT4_DEFM_DISCARD	0x0400
1899 #define EXT4_DEFM_NODELALLOC	0x0800
1900 
1901 /*
1902  * Default journal batch times
1903  */
1904 #define EXT4_DEF_MIN_BATCH_TIME	0
1905 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1906 
1907 /*
1908  * Minimum number of groups in a flexgroup before we separate out
1909  * directories into the first block group of a flexgroup
1910  */
1911 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1912 
1913 /*
1914  * Structure of a directory entry
1915  */
1916 #define EXT4_NAME_LEN 255
1917 
1918 struct ext4_dir_entry {
1919 	__le32	inode;			/* Inode number */
1920 	__le16	rec_len;		/* Directory entry length */
1921 	__le16	name_len;		/* Name length */
1922 	char	name[EXT4_NAME_LEN];	/* File name */
1923 };
1924 
1925 /*
1926  * The new version of the directory entry.  Since EXT4 structures are
1927  * stored in intel byte order, and the name_len field could never be
1928  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1929  * file_type field.
1930  */
1931 struct ext4_dir_entry_2 {
1932 	__le32	inode;			/* Inode number */
1933 	__le16	rec_len;		/* Directory entry length */
1934 	__u8	name_len;		/* Name length */
1935 	__u8	file_type;
1936 	char	name[EXT4_NAME_LEN];	/* File name */
1937 };
1938 
1939 /*
1940  * This is a bogus directory entry at the end of each leaf block that
1941  * records checksums.
1942  */
1943 struct ext4_dir_entry_tail {
1944 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1945 	__le16	det_rec_len;		/* 12 */
1946 	__u8	det_reserved_zero2;	/* Zero name length */
1947 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1948 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1949 };
1950 
1951 #define EXT4_DIRENT_TAIL(block, blocksize) \
1952 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1953 					((blocksize) - \
1954 					 sizeof(struct ext4_dir_entry_tail))))
1955 
1956 /*
1957  * Ext4 directory file types.  Only the low 3 bits are used.  The
1958  * other bits are reserved for now.
1959  */
1960 #define EXT4_FT_UNKNOWN		0
1961 #define EXT4_FT_REG_FILE	1
1962 #define EXT4_FT_DIR		2
1963 #define EXT4_FT_CHRDEV		3
1964 #define EXT4_FT_BLKDEV		4
1965 #define EXT4_FT_FIFO		5
1966 #define EXT4_FT_SOCK		6
1967 #define EXT4_FT_SYMLINK		7
1968 
1969 #define EXT4_FT_MAX		8
1970 
1971 #define EXT4_FT_DIR_CSUM	0xDE
1972 
1973 /*
1974  * EXT4_DIR_PAD defines the directory entries boundaries
1975  *
1976  * NOTE: It must be a multiple of 4
1977  */
1978 #define EXT4_DIR_PAD			4
1979 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1980 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1981 					 ~EXT4_DIR_ROUND)
1982 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1983 
1984 /*
1985  * If we ever get support for fs block sizes > page_size, we'll need
1986  * to remove the #if statements in the next two functions...
1987  */
1988 static inline unsigned int
1989 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1990 {
1991 	unsigned len = le16_to_cpu(dlen);
1992 
1993 #if (PAGE_SIZE >= 65536)
1994 	if (len == EXT4_MAX_REC_LEN || len == 0)
1995 		return blocksize;
1996 	return (len & 65532) | ((len & 3) << 16);
1997 #else
1998 	return len;
1999 #endif
2000 }
2001 
2002 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2003 {
2004 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
2005 		BUG();
2006 #if (PAGE_SIZE >= 65536)
2007 	if (len < 65536)
2008 		return cpu_to_le16(len);
2009 	if (len == blocksize) {
2010 		if (blocksize == 65536)
2011 			return cpu_to_le16(EXT4_MAX_REC_LEN);
2012 		else
2013 			return cpu_to_le16(0);
2014 	}
2015 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2016 #else
2017 	return cpu_to_le16(len);
2018 #endif
2019 }
2020 
2021 /*
2022  * Hash Tree Directory indexing
2023  * (c) Daniel Phillips, 2001
2024  */
2025 
2026 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2027 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2028 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2029 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2030 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2031 
2032 /* Legal values for the dx_root hash_version field: */
2033 
2034 #define DX_HASH_LEGACY			0
2035 #define DX_HASH_HALF_MD4		1
2036 #define DX_HASH_TEA			2
2037 #define DX_HASH_LEGACY_UNSIGNED		3
2038 #define DX_HASH_HALF_MD4_UNSIGNED	4
2039 #define DX_HASH_TEA_UNSIGNED		5
2040 
2041 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2042 			      const void *address, unsigned int length)
2043 {
2044 	struct {
2045 		struct shash_desc shash;
2046 		char ctx[4];
2047 	} desc;
2048 
2049 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2050 
2051 	desc.shash.tfm = sbi->s_chksum_driver;
2052 	*(u32 *)desc.ctx = crc;
2053 
2054 	BUG_ON(crypto_shash_update(&desc.shash, address, length));
2055 
2056 	return *(u32 *)desc.ctx;
2057 }
2058 
2059 #ifdef __KERNEL__
2060 
2061 /* hash info structure used by the directory hash */
2062 struct dx_hash_info
2063 {
2064 	u32		hash;
2065 	u32		minor_hash;
2066 	int		hash_version;
2067 	u32		*seed;
2068 };
2069 
2070 
2071 /* 32 and 64 bit signed EOF for dx directories */
2072 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2073 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2074 
2075 
2076 /*
2077  * Control parameters used by ext4_htree_next_block
2078  */
2079 #define HASH_NB_ALWAYS		1
2080 
2081 struct ext4_filename {
2082 	const struct qstr *usr_fname;
2083 	struct fscrypt_str disk_name;
2084 	struct dx_hash_info hinfo;
2085 #ifdef CONFIG_FS_ENCRYPTION
2086 	struct fscrypt_str crypto_buf;
2087 #endif
2088 #ifdef CONFIG_UNICODE
2089 	struct fscrypt_str cf_name;
2090 #endif
2091 };
2092 
2093 #define fname_name(p) ((p)->disk_name.name)
2094 #define fname_len(p)  ((p)->disk_name.len)
2095 
2096 /*
2097  * Describe an inode's exact location on disk and in memory
2098  */
2099 struct ext4_iloc
2100 {
2101 	struct buffer_head *bh;
2102 	unsigned long offset;
2103 	ext4_group_t block_group;
2104 };
2105 
2106 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2107 {
2108 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2109 }
2110 
2111 static inline bool ext4_is_quota_file(struct inode *inode)
2112 {
2113 	return IS_NOQUOTA(inode) &&
2114 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2115 }
2116 
2117 /*
2118  * This structure is stuffed into the struct file's private_data field
2119  * for directories.  It is where we put information so that we can do
2120  * readdir operations in hash tree order.
2121  */
2122 struct dir_private_info {
2123 	struct rb_root	root;
2124 	struct rb_node	*curr_node;
2125 	struct fname	*extra_fname;
2126 	loff_t		last_pos;
2127 	__u32		curr_hash;
2128 	__u32		curr_minor_hash;
2129 	__u32		next_hash;
2130 };
2131 
2132 /* calculate the first block number of the group */
2133 static inline ext4_fsblk_t
2134 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2135 {
2136 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2137 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2138 }
2139 
2140 /*
2141  * Special error return code only used by dx_probe() and its callers.
2142  */
2143 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2144 
2145 /* htree levels for ext4 */
2146 #define	EXT4_HTREE_LEVEL_COMPAT	2
2147 #define	EXT4_HTREE_LEVEL	3
2148 
2149 static inline int ext4_dir_htree_level(struct super_block *sb)
2150 {
2151 	return ext4_has_feature_largedir(sb) ?
2152 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2153 }
2154 
2155 /*
2156  * Timeout and state flag for lazy initialization inode thread.
2157  */
2158 #define EXT4_DEF_LI_WAIT_MULT			10
2159 #define EXT4_DEF_LI_MAX_START_DELAY		5
2160 #define EXT4_LAZYINIT_QUIT			0x0001
2161 #define EXT4_LAZYINIT_RUNNING			0x0002
2162 
2163 /*
2164  * Lazy inode table initialization info
2165  */
2166 struct ext4_lazy_init {
2167 	unsigned long		li_state;
2168 	struct list_head	li_request_list;
2169 	struct mutex		li_list_mtx;
2170 };
2171 
2172 struct ext4_li_request {
2173 	struct super_block	*lr_super;
2174 	struct ext4_sb_info	*lr_sbi;
2175 	ext4_group_t		lr_next_group;
2176 	struct list_head	lr_request;
2177 	unsigned long		lr_next_sched;
2178 	unsigned long		lr_timeout;
2179 };
2180 
2181 struct ext4_features {
2182 	struct kobject f_kobj;
2183 	struct completion f_kobj_unregister;
2184 };
2185 
2186 /*
2187  * This structure will be used for multiple mount protection. It will be
2188  * written into the block number saved in the s_mmp_block field in the
2189  * superblock. Programs that check MMP should assume that if
2190  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2191  * to use the filesystem, regardless of how old the timestamp is.
2192  */
2193 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2194 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2195 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2196 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2197 
2198 struct mmp_struct {
2199 	__le32	mmp_magic;		/* Magic number for MMP */
2200 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2201 
2202 	/*
2203 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2204 	 * purposes and do not affect the correctness of the algorithm
2205 	 */
2206 	__le64	mmp_time;		/* Time last updated */
2207 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2208 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2209 
2210 	/*
2211 	 * mmp_check_interval is used to verify if the MMP block has been
2212 	 * updated on the block device. The value is updated based on the
2213 	 * maximum time to write the MMP block during an update cycle.
2214 	 */
2215 	__le16	mmp_check_interval;
2216 
2217 	__le16	mmp_pad1;
2218 	__le32	mmp_pad2[226];
2219 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2220 };
2221 
2222 /* arguments passed to the mmp thread */
2223 struct mmpd_data {
2224 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2225 	struct super_block *sb;  /* super block of the fs */
2226 };
2227 
2228 /*
2229  * Check interval multiplier
2230  * The MMP block is written every update interval and initially checked every
2231  * update interval x the multiplier (the value is then adapted based on the
2232  * write latency). The reason is that writes can be delayed under load and we
2233  * don't want readers to incorrectly assume that the filesystem is no longer
2234  * in use.
2235  */
2236 #define EXT4_MMP_CHECK_MULT		2UL
2237 
2238 /*
2239  * Minimum interval for MMP checking in seconds.
2240  */
2241 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2242 
2243 /*
2244  * Maximum interval for MMP checking in seconds.
2245  */
2246 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2247 
2248 /*
2249  * Function prototypes
2250  */
2251 
2252 /*
2253  * Ok, these declarations are also in <linux/kernel.h> but none of the
2254  * ext4 source programs needs to include it so they are duplicated here.
2255  */
2256 # define NORET_TYPE	/**/
2257 # define ATTRIB_NORET	__attribute__((noreturn))
2258 # define NORET_AND	noreturn,
2259 
2260 /* bitmap.c */
2261 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2262 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2263 				struct ext4_group_desc *gdp,
2264 				struct buffer_head *bh, int sz);
2265 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2266 				  struct ext4_group_desc *gdp,
2267 				  struct buffer_head *bh, int sz);
2268 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2269 				struct ext4_group_desc *gdp,
2270 				struct buffer_head *bh);
2271 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2272 				  struct ext4_group_desc *gdp,
2273 				  struct buffer_head *bh);
2274 
2275 /* balloc.c */
2276 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2277 					 ext4_fsblk_t blocknr,
2278 					 ext4_group_t *blockgrpp,
2279 					 ext4_grpblk_t *offsetp);
2280 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2281 					  ext4_fsblk_t block);
2282 
2283 extern unsigned int ext4_block_group(struct super_block *sb,
2284 			ext4_fsblk_t blocknr);
2285 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2286 			ext4_fsblk_t blocknr);
2287 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2288 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2289 			ext4_group_t group);
2290 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2291 					 ext4_fsblk_t goal,
2292 					 unsigned int flags,
2293 					 unsigned long *count,
2294 					 int *errp);
2295 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2296 				    s64 nclusters, unsigned int flags);
2297 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2298 extern void ext4_check_blocks_bitmap(struct super_block *);
2299 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2300 						    ext4_group_t block_group,
2301 						    struct buffer_head ** bh);
2302 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2303 
2304 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2305 						ext4_group_t block_group);
2306 extern int ext4_wait_block_bitmap(struct super_block *sb,
2307 				  ext4_group_t block_group,
2308 				  struct buffer_head *bh);
2309 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2310 						  ext4_group_t block_group);
2311 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2312 					      ext4_group_t block_group,
2313 					      struct ext4_group_desc *gdp);
2314 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2315 
2316 #ifdef CONFIG_UNICODE
2317 extern void ext4_fname_setup_ci_filename(struct inode *dir,
2318 					 const struct qstr *iname,
2319 					 struct fscrypt_str *fname);
2320 #endif
2321 
2322 #ifdef CONFIG_FS_ENCRYPTION
2323 static inline void ext4_fname_from_fscrypt_name(struct ext4_filename *dst,
2324 						const struct fscrypt_name *src)
2325 {
2326 	memset(dst, 0, sizeof(*dst));
2327 
2328 	dst->usr_fname = src->usr_fname;
2329 	dst->disk_name = src->disk_name;
2330 	dst->hinfo.hash = src->hash;
2331 	dst->hinfo.minor_hash = src->minor_hash;
2332 	dst->crypto_buf = src->crypto_buf;
2333 }
2334 
2335 static inline int ext4_fname_setup_filename(struct inode *dir,
2336 					    const struct qstr *iname,
2337 					    int lookup,
2338 					    struct ext4_filename *fname)
2339 {
2340 	struct fscrypt_name name;
2341 	int err;
2342 
2343 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2344 	if (err)
2345 		return err;
2346 
2347 	ext4_fname_from_fscrypt_name(fname, &name);
2348 
2349 #ifdef CONFIG_UNICODE
2350 	ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name);
2351 #endif
2352 	return 0;
2353 }
2354 
2355 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2356 					    struct dentry *dentry,
2357 					    struct ext4_filename *fname)
2358 {
2359 	struct fscrypt_name name;
2360 	int err;
2361 
2362 	err = fscrypt_prepare_lookup(dir, dentry, &name);
2363 	if (err)
2364 		return err;
2365 
2366 	ext4_fname_from_fscrypt_name(fname, &name);
2367 
2368 #ifdef CONFIG_UNICODE
2369 	ext4_fname_setup_ci_filename(dir, &dentry->d_name, &fname->cf_name);
2370 #endif
2371 	return 0;
2372 }
2373 
2374 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2375 {
2376 	struct fscrypt_name name;
2377 
2378 	name.crypto_buf = fname->crypto_buf;
2379 	fscrypt_free_filename(&name);
2380 
2381 	fname->crypto_buf.name = NULL;
2382 	fname->usr_fname = NULL;
2383 	fname->disk_name.name = NULL;
2384 
2385 #ifdef CONFIG_UNICODE
2386 	kfree(fname->cf_name.name);
2387 	fname->cf_name.name = NULL;
2388 #endif
2389 }
2390 #else /* !CONFIG_FS_ENCRYPTION */
2391 static inline int ext4_fname_setup_filename(struct inode *dir,
2392 					    const struct qstr *iname,
2393 					    int lookup,
2394 					    struct ext4_filename *fname)
2395 {
2396 	fname->usr_fname = iname;
2397 	fname->disk_name.name = (unsigned char *) iname->name;
2398 	fname->disk_name.len = iname->len;
2399 
2400 #ifdef CONFIG_UNICODE
2401 	ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name);
2402 #endif
2403 
2404 	return 0;
2405 }
2406 
2407 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2408 					    struct dentry *dentry,
2409 					    struct ext4_filename *fname)
2410 {
2411 	return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
2412 }
2413 
2414 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2415 {
2416 #ifdef CONFIG_UNICODE
2417 	kfree(fname->cf_name.name);
2418 	fname->cf_name.name = NULL;
2419 #endif
2420 }
2421 #endif /* !CONFIG_FS_ENCRYPTION */
2422 
2423 /* dir.c */
2424 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2425 				  struct file *,
2426 				  struct ext4_dir_entry_2 *,
2427 				  struct buffer_head *, char *, int,
2428 				  unsigned int);
2429 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2430 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2431 					(de), (bh), (buf), (size), (offset)))
2432 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2433 				__u32 minor_hash,
2434 				struct ext4_dir_entry_2 *dirent,
2435 				struct fscrypt_str *ent_name);
2436 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2437 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2438 			     struct buffer_head *bh,
2439 			     void *buf, int buf_size,
2440 			     struct ext4_filename *fname,
2441 			     struct ext4_dir_entry_2 **dest_de);
2442 void ext4_insert_dentry(struct inode *inode,
2443 			struct ext4_dir_entry_2 *de,
2444 			int buf_size,
2445 			struct ext4_filename *fname);
2446 static inline void ext4_update_dx_flag(struct inode *inode)
2447 {
2448 	if (!ext4_has_feature_dir_index(inode->i_sb))
2449 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2450 }
2451 static const unsigned char ext4_filetype_table[] = {
2452 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2453 };
2454 
2455 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2456 {
2457 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2458 		return DT_UNKNOWN;
2459 
2460 	return ext4_filetype_table[filetype];
2461 }
2462 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2463 			     void *buf, int buf_size);
2464 
2465 /* fsync.c */
2466 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2467 
2468 /* hash.c */
2469 extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
2470 			  struct dx_hash_info *hinfo);
2471 
2472 /* ialloc.c */
2473 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2474 				      const struct qstr *qstr, __u32 goal,
2475 				      uid_t *owner, __u32 i_flags,
2476 				      int handle_type, unsigned int line_no,
2477 				      int nblocks);
2478 
2479 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2480 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2481 			 i_flags, 0, 0, 0)
2482 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2483 				    type, nblocks)		    \
2484 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2485 			 0, (type), __LINE__, (nblocks))
2486 
2487 
2488 extern void ext4_free_inode(handle_t *, struct inode *);
2489 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2490 extern unsigned long ext4_count_free_inodes(struct super_block *);
2491 extern unsigned long ext4_count_dirs(struct super_block *);
2492 extern void ext4_check_inodes_bitmap(struct super_block *);
2493 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2494 extern int ext4_init_inode_table(struct super_block *sb,
2495 				 ext4_group_t group, int barrier);
2496 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2497 
2498 /* mballoc.c */
2499 extern const struct seq_operations ext4_mb_seq_groups_ops;
2500 extern long ext4_mb_stats;
2501 extern long ext4_mb_max_to_scan;
2502 extern int ext4_mb_init(struct super_block *);
2503 extern int ext4_mb_release(struct super_block *);
2504 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2505 				struct ext4_allocation_request *, int *);
2506 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2507 extern void ext4_discard_preallocations(struct inode *);
2508 extern int __init ext4_init_mballoc(void);
2509 extern void ext4_exit_mballoc(void);
2510 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2511 			     struct buffer_head *bh, ext4_fsblk_t block,
2512 			     unsigned long count, int flags);
2513 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2514 				   ext4_group_t ngroups);
2515 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2516 		ext4_group_t i, struct ext4_group_desc *desc);
2517 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2518 				ext4_fsblk_t block, unsigned long count);
2519 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2520 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2521 
2522 /* inode.c */
2523 int ext4_inode_is_fast_symlink(struct inode *inode);
2524 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2525 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2526 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2527 		     bool wait, struct buffer_head **bhs);
2528 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2529 			     struct buffer_head *bh_result, int create);
2530 int ext4_get_block(struct inode *inode, sector_t iblock,
2531 		   struct buffer_head *bh_result, int create);
2532 int ext4_dio_get_block(struct inode *inode, sector_t iblock,
2533 		       struct buffer_head *bh_result, int create);
2534 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2535 			   struct buffer_head *bh, int create);
2536 int ext4_walk_page_buffers(handle_t *handle,
2537 			   struct buffer_head *head,
2538 			   unsigned from,
2539 			   unsigned to,
2540 			   int *partial,
2541 			   int (*fn)(handle_t *handle,
2542 				     struct buffer_head *bh));
2543 int do_journal_get_write_access(handle_t *handle,
2544 				struct buffer_head *bh);
2545 #define FALL_BACK_TO_NONDELALLOC 1
2546 #define CONVERT_INLINE_DATA	 2
2547 
2548 typedef enum {
2549 	EXT4_IGET_NORMAL =	0,
2550 	EXT4_IGET_SPECIAL =	0x0001, /* OK to iget a system inode */
2551 	EXT4_IGET_HANDLE = 	0x0002	/* Inode # is from a handle */
2552 } ext4_iget_flags;
2553 
2554 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2555 				 ext4_iget_flags flags, const char *function,
2556 				 unsigned int line);
2557 
2558 #define ext4_iget(sb, ino, flags) \
2559 	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2560 
2561 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2562 extern int  ext4_setattr(struct dentry *, struct iattr *);
2563 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2564 extern void ext4_evict_inode(struct inode *);
2565 extern void ext4_clear_inode(struct inode *);
2566 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2567 extern int  ext4_sync_inode(handle_t *, struct inode *);
2568 extern void ext4_dirty_inode(struct inode *, int);
2569 extern int ext4_change_inode_journal_flag(struct inode *, int);
2570 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2571 extern int ext4_inode_attach_jinode(struct inode *inode);
2572 extern int ext4_can_truncate(struct inode *inode);
2573 extern int ext4_truncate(struct inode *);
2574 extern int ext4_break_layouts(struct inode *);
2575 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2576 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2577 extern void ext4_set_inode_flags(struct inode *);
2578 extern int ext4_alloc_da_blocks(struct inode *inode);
2579 extern void ext4_set_aops(struct inode *inode);
2580 extern int ext4_writepage_trans_blocks(struct inode *);
2581 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2582 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2583 			     loff_t lstart, loff_t lend);
2584 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
2585 extern vm_fault_t ext4_filemap_fault(struct vm_fault *vmf);
2586 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2587 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2588 extern void ext4_da_release_space(struct inode *inode, int to_free);
2589 extern void ext4_da_update_reserve_space(struct inode *inode,
2590 					int used, int quota_claim);
2591 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2592 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2593 
2594 /* indirect.c */
2595 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2596 				struct ext4_map_blocks *map, int flags);
2597 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2598 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2599 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2600 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2601 				 ext4_lblk_t start, ext4_lblk_t end);
2602 
2603 /* ioctl.c */
2604 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2605 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2606 
2607 /* migrate.c */
2608 extern int ext4_ext_migrate(struct inode *);
2609 extern int ext4_ind_migrate(struct inode *inode);
2610 
2611 /* namei.c */
2612 extern int ext4_dirblock_csum_verify(struct inode *inode,
2613 				     struct buffer_head *bh);
2614 extern int ext4_orphan_add(handle_t *, struct inode *);
2615 extern int ext4_orphan_del(handle_t *, struct inode *);
2616 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2617 				__u32 start_minor_hash, __u32 *next_hash);
2618 extern int ext4_search_dir(struct buffer_head *bh,
2619 			   char *search_buf,
2620 			   int buf_size,
2621 			   struct inode *dir,
2622 			   struct ext4_filename *fname,
2623 			   unsigned int offset,
2624 			   struct ext4_dir_entry_2 **res_dir);
2625 extern int ext4_generic_delete_entry(handle_t *handle,
2626 				     struct inode *dir,
2627 				     struct ext4_dir_entry_2 *de_del,
2628 				     struct buffer_head *bh,
2629 				     void *entry_buf,
2630 				     int buf_size,
2631 				     int csum_size);
2632 extern bool ext4_empty_dir(struct inode *inode);
2633 
2634 /* resize.c */
2635 extern int ext4_group_add(struct super_block *sb,
2636 				struct ext4_new_group_data *input);
2637 extern int ext4_group_extend(struct super_block *sb,
2638 				struct ext4_super_block *es,
2639 				ext4_fsblk_t n_blocks_count);
2640 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2641 
2642 /* super.c */
2643 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
2644 					 sector_t block, int op_flags);
2645 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2646 extern int ext4_calculate_overhead(struct super_block *sb);
2647 extern void ext4_superblock_csum_set(struct super_block *sb);
2648 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2649 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2650 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2651 				    ext4_group_t ngroup);
2652 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2653 				     char nbuf[16]);
2654 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
2655 					     ext4_group_t block_group,
2656 					     unsigned int flags);
2657 
2658 extern __printf(4, 5)
2659 void __ext4_error(struct super_block *, const char *, unsigned int,
2660 		  const char *, ...);
2661 extern __printf(5, 6)
2662 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2663 		      const char *, ...);
2664 extern __printf(5, 6)
2665 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2666 		     const char *, ...);
2667 extern void __ext4_std_error(struct super_block *, const char *,
2668 			     unsigned int, int);
2669 extern __printf(4, 5)
2670 void __ext4_abort(struct super_block *, const char *, unsigned int,
2671 		  const char *, ...);
2672 extern __printf(4, 5)
2673 void __ext4_warning(struct super_block *, const char *, unsigned int,
2674 		    const char *, ...);
2675 extern __printf(4, 5)
2676 void __ext4_warning_inode(const struct inode *inode, const char *function,
2677 			  unsigned int line, const char *fmt, ...);
2678 extern __printf(3, 4)
2679 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2680 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2681 			   const char *, unsigned int, const char *);
2682 extern __printf(7, 8)
2683 void __ext4_grp_locked_error(const char *, unsigned int,
2684 			     struct super_block *, ext4_group_t,
2685 			     unsigned long, ext4_fsblk_t,
2686 			     const char *, ...);
2687 
2688 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2689 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2690 
2691 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
2692 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2693 
2694 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2695 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2696 
2697 #ifdef CONFIG_PRINTK
2698 
2699 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2700 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2701 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2702 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2703 #define ext4_error(sb, fmt, ...)					\
2704 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2705 #define ext4_abort(sb, fmt, ...)					\
2706 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2707 #define ext4_warning(sb, fmt, ...)					\
2708 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2709 #define ext4_warning_inode(inode, fmt, ...)				\
2710 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2711 #define ext4_msg(sb, level, fmt, ...)				\
2712 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2713 #define dump_mmp_msg(sb, mmp, msg)					\
2714 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2715 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2716 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2717 				fmt, ##__VA_ARGS__)
2718 
2719 #else
2720 
2721 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2722 do {									\
2723 	no_printk(fmt, ##__VA_ARGS__);					\
2724 	__ext4_error_inode(inode, "", 0, block, " ");			\
2725 } while (0)
2726 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2727 do {									\
2728 	no_printk(fmt, ##__VA_ARGS__);					\
2729 	__ext4_error_file(file, "", 0, block, " ");			\
2730 } while (0)
2731 #define ext4_error(sb, fmt, ...)					\
2732 do {									\
2733 	no_printk(fmt, ##__VA_ARGS__);					\
2734 	__ext4_error(sb, "", 0, " ");					\
2735 } while (0)
2736 #define ext4_abort(sb, fmt, ...)					\
2737 do {									\
2738 	no_printk(fmt, ##__VA_ARGS__);					\
2739 	__ext4_abort(sb, "", 0, " ");					\
2740 } while (0)
2741 #define ext4_warning(sb, fmt, ...)					\
2742 do {									\
2743 	no_printk(fmt, ##__VA_ARGS__);					\
2744 	__ext4_warning(sb, "", 0, " ");					\
2745 } while (0)
2746 #define ext4_warning_inode(inode, fmt, ...)				\
2747 do {									\
2748 	no_printk(fmt, ##__VA_ARGS__);					\
2749 	__ext4_warning_inode(inode, "", 0, " ");			\
2750 } while (0)
2751 #define ext4_msg(sb, level, fmt, ...)					\
2752 do {									\
2753 	no_printk(fmt, ##__VA_ARGS__);					\
2754 	__ext4_msg(sb, "", " ");					\
2755 } while (0)
2756 #define dump_mmp_msg(sb, mmp, msg)					\
2757 	__dump_mmp_msg(sb, mmp, "", 0, "")
2758 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2759 do {									\
2760 	no_printk(fmt, ##__VA_ARGS__);				\
2761 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2762 } while (0)
2763 
2764 #endif
2765 
2766 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2767 					__u32 compat);
2768 extern int ext4_update_rocompat_feature(handle_t *handle,
2769 					struct super_block *sb,	__u32 rocompat);
2770 extern int ext4_update_incompat_feature(handle_t *handle,
2771 					struct super_block *sb,	__u32 incompat);
2772 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2773 				      struct ext4_group_desc *bg);
2774 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2775 				      struct ext4_group_desc *bg);
2776 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2777 				     struct ext4_group_desc *bg);
2778 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2779 				      struct ext4_group_desc *bg);
2780 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2781 				 struct ext4_group_desc *bg);
2782 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2783 				struct ext4_group_desc *bg);
2784 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2785 				   struct ext4_group_desc *bg);
2786 extern void ext4_block_bitmap_set(struct super_block *sb,
2787 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2788 extern void ext4_inode_bitmap_set(struct super_block *sb,
2789 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2790 extern void ext4_inode_table_set(struct super_block *sb,
2791 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2792 extern void ext4_free_group_clusters_set(struct super_block *sb,
2793 					 struct ext4_group_desc *bg,
2794 					 __u32 count);
2795 extern void ext4_free_inodes_set(struct super_block *sb,
2796 				struct ext4_group_desc *bg, __u32 count);
2797 extern void ext4_used_dirs_set(struct super_block *sb,
2798 				struct ext4_group_desc *bg, __u32 count);
2799 extern void ext4_itable_unused_set(struct super_block *sb,
2800 				   struct ext4_group_desc *bg, __u32 count);
2801 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2802 				       struct ext4_group_desc *gdp);
2803 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2804 				     struct ext4_group_desc *gdp);
2805 extern int ext4_register_li_request(struct super_block *sb,
2806 				    ext4_group_t first_not_zeroed);
2807 
2808 static inline int ext4_has_metadata_csum(struct super_block *sb)
2809 {
2810 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2811 		     !EXT4_SB(sb)->s_chksum_driver);
2812 
2813 	return ext4_has_feature_metadata_csum(sb) &&
2814 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
2815 }
2816 
2817 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2818 {
2819 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
2820 }
2821 
2822 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2823 {
2824 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2825 		le32_to_cpu(es->s_blocks_count_lo);
2826 }
2827 
2828 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2829 {
2830 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2831 		le32_to_cpu(es->s_r_blocks_count_lo);
2832 }
2833 
2834 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2835 {
2836 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2837 		le32_to_cpu(es->s_free_blocks_count_lo);
2838 }
2839 
2840 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2841 					 ext4_fsblk_t blk)
2842 {
2843 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2844 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2845 }
2846 
2847 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2848 					      ext4_fsblk_t blk)
2849 {
2850 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2851 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2852 }
2853 
2854 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2855 					   ext4_fsblk_t blk)
2856 {
2857 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2858 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2859 }
2860 
2861 static inline loff_t ext4_isize(struct super_block *sb,
2862 				struct ext4_inode *raw_inode)
2863 {
2864 	if (ext4_has_feature_largedir(sb) ||
2865 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2866 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2867 			le32_to_cpu(raw_inode->i_size_lo);
2868 
2869 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2870 }
2871 
2872 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2873 {
2874 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2875 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2876 }
2877 
2878 static inline
2879 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2880 					    ext4_group_t group)
2881 {
2882 	 struct ext4_group_info ***grp_info;
2883 	 long indexv, indexh;
2884 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2885 	 grp_info = EXT4_SB(sb)->s_group_info;
2886 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2887 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2888 	 return grp_info[indexv][indexh];
2889 }
2890 
2891 /*
2892  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2893  * the locking protocol documented in the comments of ext4_group_add()
2894  * in resize.c
2895  */
2896 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2897 {
2898 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2899 
2900 	smp_rmb();
2901 	return ngroups;
2902 }
2903 
2904 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2905 					     ext4_group_t block_group)
2906 {
2907 	return block_group >> sbi->s_log_groups_per_flex;
2908 }
2909 
2910 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2911 {
2912 	return 1 << sbi->s_log_groups_per_flex;
2913 }
2914 
2915 #define ext4_std_error(sb, errno)				\
2916 do {								\
2917 	if ((errno))						\
2918 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2919 } while (0)
2920 
2921 #ifdef CONFIG_SMP
2922 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2923  * counters. So we need to make sure we have free clusters more
2924  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2925  */
2926 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2927 #else
2928 #define EXT4_FREECLUSTERS_WATERMARK 0
2929 #endif
2930 
2931 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2932 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2933 {
2934 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2935 		     !inode_is_locked(inode));
2936 	down_write(&EXT4_I(inode)->i_data_sem);
2937 	if (newsize > EXT4_I(inode)->i_disksize)
2938 		EXT4_I(inode)->i_disksize = newsize;
2939 	up_write(&EXT4_I(inode)->i_data_sem);
2940 }
2941 
2942 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2943 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2944 {
2945 	int changed = 0;
2946 
2947 	if (newsize > inode->i_size) {
2948 		i_size_write(inode, newsize);
2949 		changed = 1;
2950 	}
2951 	if (newsize > EXT4_I(inode)->i_disksize) {
2952 		ext4_update_i_disksize(inode, newsize);
2953 		changed |= 2;
2954 	}
2955 	return changed;
2956 }
2957 
2958 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2959 				      loff_t len);
2960 
2961 struct ext4_group_info {
2962 	unsigned long   bb_state;
2963 	struct rb_root  bb_free_root;
2964 	ext4_grpblk_t	bb_first_free;	/* first free block */
2965 	ext4_grpblk_t	bb_free;	/* total free blocks */
2966 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2967 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2968 	struct          list_head bb_prealloc_list;
2969 #ifdef DOUBLE_CHECK
2970 	void            *bb_bitmap;
2971 #endif
2972 	struct rw_semaphore alloc_sem;
2973 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2974 					 * regions, index is order.
2975 					 * bb_counters[3] = 5 means
2976 					 * 5 free 8-block regions. */
2977 };
2978 
2979 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2980 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2981 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2982 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2983 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT		\
2984 	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
2985 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT		\
2986 	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
2987 
2988 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2989 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2990 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2991 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2992 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2993 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2994 
2995 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2996 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2997 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2998 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2999 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
3000 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
3001 
3002 #define EXT4_MAX_CONTENTION		8
3003 #define EXT4_CONTENTION_THRESHOLD	2
3004 
3005 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
3006 					      ext4_group_t group)
3007 {
3008 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
3009 }
3010 
3011 /*
3012  * Returns true if the filesystem is busy enough that attempts to
3013  * access the block group locks has run into contention.
3014  */
3015 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
3016 {
3017 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
3018 }
3019 
3020 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
3021 {
3022 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
3023 	if (spin_trylock(lock))
3024 		/*
3025 		 * We're able to grab the lock right away, so drop the
3026 		 * lock contention counter.
3027 		 */
3028 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
3029 	else {
3030 		/*
3031 		 * The lock is busy, so bump the contention counter,
3032 		 * and then wait on the spin lock.
3033 		 */
3034 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
3035 				  EXT4_MAX_CONTENTION);
3036 		spin_lock(lock);
3037 	}
3038 }
3039 
3040 static inline void ext4_unlock_group(struct super_block *sb,
3041 					ext4_group_t group)
3042 {
3043 	spin_unlock(ext4_group_lock_ptr(sb, group));
3044 }
3045 
3046 /*
3047  * Block validity checking
3048  */
3049 #define ext4_check_indirect_blockref(inode, bh)				\
3050 	ext4_check_blockref(__func__, __LINE__, inode,			\
3051 			    (__le32 *)(bh)->b_data,			\
3052 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3053 
3054 #define ext4_ind_check_inode(inode)					\
3055 	ext4_check_blockref(__func__, __LINE__, inode,			\
3056 			    EXT4_I(inode)->i_data,			\
3057 			    EXT4_NDIR_BLOCKS)
3058 
3059 /*
3060  * Inodes and files operations
3061  */
3062 
3063 /* dir.c */
3064 extern const struct file_operations ext4_dir_operations;
3065 
3066 #ifdef CONFIG_UNICODE
3067 extern const struct dentry_operations ext4_dentry_ops;
3068 #endif
3069 
3070 /* file.c */
3071 extern const struct inode_operations ext4_file_inode_operations;
3072 extern const struct file_operations ext4_file_operations;
3073 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
3074 
3075 /* inline.c */
3076 extern int ext4_get_max_inline_size(struct inode *inode);
3077 extern int ext4_find_inline_data_nolock(struct inode *inode);
3078 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
3079 				 unsigned int len);
3080 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3081 
3082 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
3083 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3084 					 struct inode *inode,
3085 					 loff_t pos, unsigned len,
3086 					 unsigned flags,
3087 					 struct page **pagep);
3088 extern int ext4_write_inline_data_end(struct inode *inode,
3089 				      loff_t pos, unsigned len,
3090 				      unsigned copied,
3091 				      struct page *page);
3092 extern struct buffer_head *
3093 ext4_journalled_write_inline_data(struct inode *inode,
3094 				  unsigned len,
3095 				  struct page *page);
3096 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3097 					   struct inode *inode,
3098 					   loff_t pos, unsigned len,
3099 					   unsigned flags,
3100 					   struct page **pagep,
3101 					   void **fsdata);
3102 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3103 					 unsigned len, unsigned copied,
3104 					 struct page *page);
3105 extern int ext4_try_add_inline_entry(handle_t *handle,
3106 				     struct ext4_filename *fname,
3107 				     struct inode *dir, struct inode *inode);
3108 extern int ext4_try_create_inline_dir(handle_t *handle,
3109 				      struct inode *parent,
3110 				      struct inode *inode);
3111 extern int ext4_read_inline_dir(struct file *filp,
3112 				struct dir_context *ctx,
3113 				int *has_inline_data);
3114 extern int ext4_inlinedir_to_tree(struct file *dir_file,
3115 				  struct inode *dir, ext4_lblk_t block,
3116 				  struct dx_hash_info *hinfo,
3117 				  __u32 start_hash, __u32 start_minor_hash,
3118 				  int *has_inline_data);
3119 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3120 					struct ext4_filename *fname,
3121 					struct ext4_dir_entry_2 **res_dir,
3122 					int *has_inline_data);
3123 extern int ext4_delete_inline_entry(handle_t *handle,
3124 				    struct inode *dir,
3125 				    struct ext4_dir_entry_2 *de_del,
3126 				    struct buffer_head *bh,
3127 				    int *has_inline_data);
3128 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3129 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3130 					struct ext4_dir_entry_2 **parent_de,
3131 					int *retval);
3132 extern int ext4_inline_data_fiemap(struct inode *inode,
3133 				   struct fiemap_extent_info *fieinfo,
3134 				   int *has_inline, __u64 start, __u64 len);
3135 
3136 struct iomap;
3137 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3138 
3139 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3140 
3141 extern int ext4_convert_inline_data(struct inode *inode);
3142 
3143 static inline int ext4_has_inline_data(struct inode *inode)
3144 {
3145 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3146 	       EXT4_I(inode)->i_inline_off;
3147 }
3148 
3149 /* namei.c */
3150 extern const struct inode_operations ext4_dir_inode_operations;
3151 extern const struct inode_operations ext4_special_inode_operations;
3152 extern struct dentry *ext4_get_parent(struct dentry *child);
3153 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3154 				 struct ext4_dir_entry_2 *de,
3155 				 int blocksize, int csum_size,
3156 				 unsigned int parent_ino, int dotdot_real_len);
3157 extern void ext4_initialize_dirent_tail(struct buffer_head *bh,
3158 					unsigned int blocksize);
3159 extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
3160 				      struct buffer_head *bh);
3161 extern int ext4_ci_compare(const struct inode *parent,
3162 			   const struct qstr *fname,
3163 			   const struct qstr *entry, bool quick);
3164 
3165 #define S_SHIFT 12
3166 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3167 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3168 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3169 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3170 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3171 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3172 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3173 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3174 };
3175 
3176 static inline void ext4_set_de_type(struct super_block *sb,
3177 				struct ext4_dir_entry_2 *de,
3178 				umode_t mode) {
3179 	if (ext4_has_feature_filetype(sb))
3180 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3181 }
3182 
3183 /* readpages.c */
3184 extern int ext4_mpage_readpages(struct address_space *mapping,
3185 				struct list_head *pages, struct page *page,
3186 				unsigned nr_pages, bool is_readahead);
3187 
3188 /* symlink.c */
3189 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3190 extern const struct inode_operations ext4_symlink_inode_operations;
3191 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3192 
3193 /* sysfs.c */
3194 extern int ext4_register_sysfs(struct super_block *sb);
3195 extern void ext4_unregister_sysfs(struct super_block *sb);
3196 extern int __init ext4_init_sysfs(void);
3197 extern void ext4_exit_sysfs(void);
3198 
3199 /* block_validity */
3200 extern void ext4_release_system_zone(struct super_block *sb);
3201 extern int ext4_setup_system_zone(struct super_block *sb);
3202 extern int __init ext4_init_system_zone(void);
3203 extern void ext4_exit_system_zone(void);
3204 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3205 				 ext4_fsblk_t start_blk,
3206 				 unsigned int count);
3207 extern int ext4_check_blockref(const char *, unsigned int,
3208 			       struct inode *, __le32 *, unsigned int);
3209 
3210 /* extents.c */
3211 struct ext4_ext_path;
3212 struct ext4_extent;
3213 
3214 /*
3215  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3216  * __le32.
3217  */
3218 #define EXT_MAX_BLOCKS	0xffffffff
3219 
3220 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
3221 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
3222 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3223 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3224 			       struct ext4_map_blocks *map, int flags);
3225 extern int ext4_ext_truncate(handle_t *, struct inode *);
3226 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3227 				 ext4_lblk_t end);
3228 extern void ext4_ext_init(struct super_block *);
3229 extern void ext4_ext_release(struct super_block *);
3230 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3231 			  loff_t len);
3232 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3233 					  loff_t offset, ssize_t len);
3234 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3235 			   struct ext4_map_blocks *map, int flags);
3236 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
3237 					 ext4_lblk_t lblocks);
3238 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3239 						   int num,
3240 						   struct ext4_ext_path *path);
3241 extern int ext4_can_extents_be_merged(struct inode *inode,
3242 				      struct ext4_extent *ex1,
3243 				      struct ext4_extent *ex2);
3244 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3245 				  struct ext4_ext_path **,
3246 				  struct ext4_extent *, int);
3247 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3248 					      struct ext4_ext_path **,
3249 					      int flags);
3250 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3251 extern int ext4_ext_check_inode(struct inode *inode);
3252 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3253 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3254 			__u64 start, __u64 len);
3255 extern int ext4_get_es_cache(struct inode *inode,
3256 			     struct fiemap_extent_info *fieinfo,
3257 			     __u64 start, __u64 len);
3258 extern int ext4_ext_precache(struct inode *inode);
3259 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
3260 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
3261 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3262 				struct inode *inode2, ext4_lblk_t lblk1,
3263 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3264 			     int mark_unwritten,int *err);
3265 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3266 
3267 /* move_extent.c */
3268 extern void ext4_double_down_write_data_sem(struct inode *first,
3269 					    struct inode *second);
3270 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3271 					  struct inode *donor_inode);
3272 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3273 			     __u64 start_orig, __u64 start_donor,
3274 			     __u64 len, __u64 *moved_len);
3275 
3276 /* page-io.c */
3277 extern int __init ext4_init_pageio(void);
3278 extern void ext4_exit_pageio(void);
3279 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3280 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3281 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3282 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3283 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3284 				struct writeback_control *wbc);
3285 extern void ext4_end_io_rsv_work(struct work_struct *work);
3286 extern void ext4_io_submit(struct ext4_io_submit *io);
3287 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3288 			       struct page *page,
3289 			       int len,
3290 			       struct writeback_control *wbc,
3291 			       bool keep_towrite);
3292 
3293 /* mmp.c */
3294 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3295 
3296 /*
3297  * Add new method to test whether block and inode bitmaps are properly
3298  * initialized. With uninit_bg reading the block from disk is not enough
3299  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3300  */
3301 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3302 
3303 static inline int bitmap_uptodate(struct buffer_head *bh)
3304 {
3305 	return (buffer_uptodate(bh) &&
3306 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3307 }
3308 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3309 {
3310 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3311 }
3312 
3313 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3314 
3315 /* For ioend & aio unwritten conversion wait queues */
3316 #define EXT4_WQ_HASH_SZ		37
3317 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3318 					    EXT4_WQ_HASH_SZ])
3319 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3320 
3321 extern int ext4_resize_begin(struct super_block *sb);
3322 extern void ext4_resize_end(struct super_block *sb);
3323 
3324 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3325 					      struct ext4_io_end *io_end)
3326 {
3327 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3328 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3329 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3330 	}
3331 }
3332 
3333 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3334 {
3335 	struct inode *inode = io_end->inode;
3336 
3337 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3338 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3339 		/* Wake up anyone waiting on unwritten extent conversion */
3340 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3341 			wake_up_all(ext4_ioend_wq(inode));
3342 	}
3343 }
3344 
3345 extern const struct iomap_ops ext4_iomap_ops;
3346 
3347 static inline int ext4_buffer_uptodate(struct buffer_head *bh)
3348 {
3349 	/*
3350 	 * If the buffer has the write error flag, we have failed
3351 	 * to write out data in the block.  In this  case, we don't
3352 	 * have to read the block because we may read the old data
3353 	 * successfully.
3354 	 */
3355 	if (!buffer_uptodate(bh) && buffer_write_io_error(bh))
3356 		set_buffer_uptodate(bh);
3357 	return buffer_uptodate(bh);
3358 }
3359 
3360 #endif	/* __KERNEL__ */
3361 
3362 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3363 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3364 
3365 #endif	/* _EXT4_H */
3366