xref: /openbmc/linux/fs/ext4/ext4.h (revision 2596e07a)
1 /*
2  *  ext4.h
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/include/linux/minix_fs.h
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  */
15 
16 #ifndef _EXT4_H
17 #define _EXT4_H
18 
19 #include <linux/types.h>
20 #include <linux/blkdev.h>
21 #include <linux/magic.h>
22 #include <linux/jbd2.h>
23 #include <linux/quota.h>
24 #include <linux/rwsem.h>
25 #include <linux/rbtree.h>
26 #include <linux/seqlock.h>
27 #include <linux/mutex.h>
28 #include <linux/timer.h>
29 #include <linux/version.h>
30 #include <linux/wait.h>
31 #include <linux/blockgroup_lock.h>
32 #include <linux/percpu_counter.h>
33 #include <linux/ratelimit.h>
34 #include <crypto/hash.h>
35 #include <linux/falloc.h>
36 #ifdef __KERNEL__
37 #include <linux/compat.h>
38 #endif
39 
40 /*
41  * The fourth extended filesystem constants/structures
42  */
43 
44 /*
45  * Define EXT4FS_DEBUG to produce debug messages
46  */
47 #undef EXT4FS_DEBUG
48 
49 /*
50  * Debug code
51  */
52 #ifdef EXT4FS_DEBUG
53 #define ext4_debug(f, a...)						\
54 	do {								\
55 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
56 			__FILE__, __LINE__, __func__);			\
57 		printk(KERN_DEBUG f, ## a);				\
58 	} while (0)
59 #else
60 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
61 #endif
62 
63 /*
64  * Turn on EXT_DEBUG to get lots of info about extents operations.
65  */
66 #define EXT_DEBUG__
67 #ifdef EXT_DEBUG
68 #define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
69 #else
70 #define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
71 #endif
72 
73 /* data type for block offset of block group */
74 typedef int ext4_grpblk_t;
75 
76 /* data type for filesystem-wide blocks number */
77 typedef unsigned long long ext4_fsblk_t;
78 
79 /* data type for file logical block number */
80 typedef __u32 ext4_lblk_t;
81 
82 /* data type for block group number */
83 typedef unsigned int ext4_group_t;
84 
85 enum SHIFT_DIRECTION {
86 	SHIFT_LEFT = 0,
87 	SHIFT_RIGHT,
88 };
89 
90 /*
91  * Flags used in mballoc's allocation_context flags field.
92  *
93  * Also used to show what's going on for debugging purposes when the
94  * flag field is exported via the traceport interface
95  */
96 
97 /* prefer goal again. length */
98 #define EXT4_MB_HINT_MERGE		0x0001
99 /* blocks already reserved */
100 #define EXT4_MB_HINT_RESERVED		0x0002
101 /* metadata is being allocated */
102 #define EXT4_MB_HINT_METADATA		0x0004
103 /* first blocks in the file */
104 #define EXT4_MB_HINT_FIRST		0x0008
105 /* search for the best chunk */
106 #define EXT4_MB_HINT_BEST		0x0010
107 /* data is being allocated */
108 #define EXT4_MB_HINT_DATA		0x0020
109 /* don't preallocate (for tails) */
110 #define EXT4_MB_HINT_NOPREALLOC		0x0040
111 /* allocate for locality group */
112 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
113 /* allocate goal blocks or none */
114 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
115 /* goal is meaningful */
116 #define EXT4_MB_HINT_TRY_GOAL		0x0200
117 /* blocks already pre-reserved by delayed allocation */
118 #define EXT4_MB_DELALLOC_RESERVED	0x0400
119 /* We are doing stream allocation */
120 #define EXT4_MB_STREAM_ALLOC		0x0800
121 /* Use reserved root blocks if needed */
122 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
123 /* Use blocks from reserved pool */
124 #define EXT4_MB_USE_RESERVED		0x2000
125 
126 struct ext4_allocation_request {
127 	/* target inode for block we're allocating */
128 	struct inode *inode;
129 	/* how many blocks we want to allocate */
130 	unsigned int len;
131 	/* logical block in target inode */
132 	ext4_lblk_t logical;
133 	/* the closest logical allocated block to the left */
134 	ext4_lblk_t lleft;
135 	/* the closest logical allocated block to the right */
136 	ext4_lblk_t lright;
137 	/* phys. target (a hint) */
138 	ext4_fsblk_t goal;
139 	/* phys. block for the closest logical allocated block to the left */
140 	ext4_fsblk_t pleft;
141 	/* phys. block for the closest logical allocated block to the right */
142 	ext4_fsblk_t pright;
143 	/* flags. see above EXT4_MB_HINT_* */
144 	unsigned int flags;
145 };
146 
147 /*
148  * Logical to physical block mapping, used by ext4_map_blocks()
149  *
150  * This structure is used to pass requests into ext4_map_blocks() as
151  * well as to store the information returned by ext4_map_blocks().  It
152  * takes less room on the stack than a struct buffer_head.
153  */
154 #define EXT4_MAP_NEW		(1 << BH_New)
155 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
156 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
157 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
158 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
159 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
160 
161 struct ext4_map_blocks {
162 	ext4_fsblk_t m_pblk;
163 	ext4_lblk_t m_lblk;
164 	unsigned int m_len;
165 	unsigned int m_flags;
166 };
167 
168 /*
169  * Flags for ext4_io_end->flags
170  */
171 #define	EXT4_IO_END_UNWRITTEN	0x0001
172 
173 /*
174  * For converting unwritten extents on a work queue. 'handle' is used for
175  * buffered writeback.
176  */
177 typedef struct ext4_io_end {
178 	struct list_head	list;		/* per-file finished IO list */
179 	handle_t		*handle;	/* handle reserved for extent
180 						 * conversion */
181 	struct inode		*inode;		/* file being written to */
182 	struct bio		*bio;		/* Linked list of completed
183 						 * bios covering the extent */
184 	unsigned int		flag;		/* unwritten or not */
185 	loff_t			offset;		/* offset in the file */
186 	ssize_t			size;		/* size of the extent */
187 	atomic_t		count;		/* reference counter */
188 } ext4_io_end_t;
189 
190 struct ext4_io_submit {
191 	struct writeback_control *io_wbc;
192 	struct bio		*io_bio;
193 	ext4_io_end_t		*io_end;
194 	sector_t		io_next_block;
195 };
196 
197 /*
198  * Special inodes numbers
199  */
200 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
201 #define EXT4_ROOT_INO		 2	/* Root inode */
202 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
203 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
204 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
205 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
206 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
207 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
208 
209 /* First non-reserved inode for old ext4 filesystems */
210 #define EXT4_GOOD_OLD_FIRST_INO	11
211 
212 /*
213  * Maximal count of links to a file
214  */
215 #define EXT4_LINK_MAX		65000
216 
217 /*
218  * Macro-instructions used to manage several block sizes
219  */
220 #define EXT4_MIN_BLOCK_SIZE		1024
221 #define	EXT4_MAX_BLOCK_SIZE		65536
222 #define EXT4_MIN_BLOCK_LOG_SIZE		10
223 #define EXT4_MAX_BLOCK_LOG_SIZE		16
224 #ifdef __KERNEL__
225 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
226 #else
227 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
228 #endif
229 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
230 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
231 					 EXT4_SB(s)->s_cluster_bits)
232 #ifdef __KERNEL__
233 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
234 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
235 #else
236 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
237 #endif
238 #ifdef __KERNEL__
239 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
240 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
241 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
242 #else
243 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
244 				 EXT4_GOOD_OLD_INODE_SIZE : \
245 				 (s)->s_inode_size)
246 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
247 				 EXT4_GOOD_OLD_FIRST_INO : \
248 				 (s)->s_first_ino)
249 #endif
250 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
251 
252 /* Translate a block number to a cluster number */
253 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
254 /* Translate a cluster number to a block number */
255 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
256 /* Translate # of blks to # of clusters */
257 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
258 				 (sbi)->s_cluster_bits)
259 /* Mask out the low bits to get the starting block of the cluster */
260 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
261 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
262 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
263 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
264 /* Get the cluster offset */
265 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
266 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
267 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
268 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
269 
270 /*
271  * Structure of a blocks group descriptor
272  */
273 struct ext4_group_desc
274 {
275 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
276 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
277 	__le32	bg_inode_table_lo;	/* Inodes table block */
278 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
279 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
280 	__le16	bg_used_dirs_count_lo;	/* Directories count */
281 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
282 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
283 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
284 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
285 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
286 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
287 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
288 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
289 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
290 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
291 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
292 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
293 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
294 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
295 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
296 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
297 	__u32   bg_reserved;
298 };
299 
300 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
301 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
302 	 sizeof(__le16))
303 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
304 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
305 	 sizeof(__le16))
306 
307 /*
308  * Structure of a flex block group info
309  */
310 
311 struct flex_groups {
312 	atomic64_t	free_clusters;
313 	atomic_t	free_inodes;
314 	atomic_t	used_dirs;
315 };
316 
317 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
318 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
319 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
320 
321 /*
322  * Macro-instructions used to manage group descriptors
323  */
324 #define EXT4_MIN_DESC_SIZE		32
325 #define EXT4_MIN_DESC_SIZE_64BIT	64
326 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
327 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
328 #ifdef __KERNEL__
329 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
330 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
331 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
332 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
333 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
334 #else
335 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
336 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
337 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
338 #endif
339 
340 /*
341  * Constants relative to the data blocks
342  */
343 #define	EXT4_NDIR_BLOCKS		12
344 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
345 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
346 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
347 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
348 
349 /*
350  * Inode flags
351  */
352 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
353 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
354 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
355 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
356 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
357 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
358 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
359 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
360 /* Reserved for compression usage... */
361 #define EXT4_DIRTY_FL			0x00000100
362 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
363 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
364 	/* nb: was previously EXT2_ECOMPR_FL */
365 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
366 /* End compression flags --- maybe not all used */
367 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
368 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
369 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
370 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
371 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
372 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
373 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
374 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
375 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
376 #define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
377 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
378 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
379 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
380 
381 #define EXT4_FL_USER_VISIBLE		0x304BDFFF /* User visible flags */
382 #define EXT4_FL_USER_MODIFIABLE		0x204380FF /* User modifiable flags */
383 
384 #define EXT4_FL_XFLAG_VISIBLE		(EXT4_SYNC_FL | \
385 					 EXT4_IMMUTABLE_FL | \
386 					 EXT4_APPEND_FL | \
387 					 EXT4_NODUMP_FL | \
388 					 EXT4_NOATIME_FL | \
389 					 EXT4_PROJINHERIT_FL)
390 
391 /* Flags that should be inherited by new inodes from their parent. */
392 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
393 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
394 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
395 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
396 			   EXT4_PROJINHERIT_FL)
397 
398 /* Flags that are appropriate for regular files (all but dir-specific ones). */
399 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
400 
401 /* Flags that are appropriate for non-directories/regular files. */
402 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
403 
404 /* Mask out flags that are inappropriate for the given type of inode. */
405 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
406 {
407 	if (S_ISDIR(mode))
408 		return flags;
409 	else if (S_ISREG(mode))
410 		return flags & EXT4_REG_FLMASK;
411 	else
412 		return flags & EXT4_OTHER_FLMASK;
413 }
414 
415 /*
416  * Inode flags used for atomic set/get
417  */
418 enum {
419 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
420 	EXT4_INODE_UNRM		= 1,	/* Undelete */
421 	EXT4_INODE_COMPR	= 2,	/* Compress file */
422 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
423 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
424 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
425 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
426 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
427 /* Reserved for compression usage... */
428 	EXT4_INODE_DIRTY	= 8,
429 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
430 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
431 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
432 /* End compression flags --- maybe not all used */
433 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
434 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
435 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
436 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
437 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
438 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
439 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
440 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
441 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
442 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
443 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
444 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
445 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
446 };
447 
448 /*
449  * Since it's pretty easy to mix up bit numbers and hex values, we use a
450  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
451  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
452  * any extra space in the compiled kernel image, otherwise, the build will fail.
453  * It's important that these values are the same, since we are using
454  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
455  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
456  * values found in ext2, ext3 and ext4 filesystems, and of course the values
457  * defined in e2fsprogs.
458  *
459  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
460  */
461 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
462 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
463 
464 static inline void ext4_check_flag_values(void)
465 {
466 	CHECK_FLAG_VALUE(SECRM);
467 	CHECK_FLAG_VALUE(UNRM);
468 	CHECK_FLAG_VALUE(COMPR);
469 	CHECK_FLAG_VALUE(SYNC);
470 	CHECK_FLAG_VALUE(IMMUTABLE);
471 	CHECK_FLAG_VALUE(APPEND);
472 	CHECK_FLAG_VALUE(NODUMP);
473 	CHECK_FLAG_VALUE(NOATIME);
474 	CHECK_FLAG_VALUE(DIRTY);
475 	CHECK_FLAG_VALUE(COMPRBLK);
476 	CHECK_FLAG_VALUE(NOCOMPR);
477 	CHECK_FLAG_VALUE(ENCRYPT);
478 	CHECK_FLAG_VALUE(INDEX);
479 	CHECK_FLAG_VALUE(IMAGIC);
480 	CHECK_FLAG_VALUE(JOURNAL_DATA);
481 	CHECK_FLAG_VALUE(NOTAIL);
482 	CHECK_FLAG_VALUE(DIRSYNC);
483 	CHECK_FLAG_VALUE(TOPDIR);
484 	CHECK_FLAG_VALUE(HUGE_FILE);
485 	CHECK_FLAG_VALUE(EXTENTS);
486 	CHECK_FLAG_VALUE(EA_INODE);
487 	CHECK_FLAG_VALUE(EOFBLOCKS);
488 	CHECK_FLAG_VALUE(INLINE_DATA);
489 	CHECK_FLAG_VALUE(PROJINHERIT);
490 	CHECK_FLAG_VALUE(RESERVED);
491 }
492 
493 /* Used to pass group descriptor data when online resize is done */
494 struct ext4_new_group_input {
495 	__u32 group;		/* Group number for this data */
496 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
497 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
498 	__u64 inode_table;	/* Absolute block number of inode table start */
499 	__u32 blocks_count;	/* Total number of blocks in this group */
500 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
501 	__u16 unused;
502 };
503 
504 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
505 struct compat_ext4_new_group_input {
506 	u32 group;
507 	compat_u64 block_bitmap;
508 	compat_u64 inode_bitmap;
509 	compat_u64 inode_table;
510 	u32 blocks_count;
511 	u16 reserved_blocks;
512 	u16 unused;
513 };
514 #endif
515 
516 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
517 struct ext4_new_group_data {
518 	__u32 group;
519 	__u64 block_bitmap;
520 	__u64 inode_bitmap;
521 	__u64 inode_table;
522 	__u32 blocks_count;
523 	__u16 reserved_blocks;
524 	__u16 unused;
525 	__u32 free_blocks_count;
526 };
527 
528 /* Indexes used to index group tables in ext4_new_group_data */
529 enum {
530 	BLOCK_BITMAP = 0,	/* block bitmap */
531 	INODE_BITMAP,		/* inode bitmap */
532 	INODE_TABLE,		/* inode tables */
533 	GROUP_TABLE_COUNT,
534 };
535 
536 /*
537  * Flags used by ext4_map_blocks()
538  */
539 	/* Allocate any needed blocks and/or convert an unwritten
540 	   extent to be an initialized ext4 */
541 #define EXT4_GET_BLOCKS_CREATE			0x0001
542 	/* Request the creation of an unwritten extent */
543 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
544 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
545 						 EXT4_GET_BLOCKS_CREATE)
546 	/* Caller is from the delayed allocation writeout path
547 	 * finally doing the actual allocation of delayed blocks */
548 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
549 	/* caller is from the direct IO path, request to creation of an
550 	unwritten extents if not allocated, split the unwritten
551 	extent if blocks has been preallocated already*/
552 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
553 #define EXT4_GET_BLOCKS_CONVERT			0x0010
554 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
555 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
556 	/* Convert extent to initialized after IO complete */
557 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
558 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
559 	/* Eventual metadata allocation (due to growing extent tree)
560 	 * should not fail, so try to use reserved blocks for that.*/
561 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
562 	/* Don't normalize allocation size (used for fallocate) */
563 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
564 	/* Request will not result in inode size update (user for fallocate) */
565 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
566 	/* Convert written extents to unwritten */
567 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
568 	/* Write zeros to newly created written extents */
569 #define EXT4_GET_BLOCKS_ZERO			0x0200
570 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
571 					EXT4_GET_BLOCKS_ZERO)
572 
573 /*
574  * The bit position of these flags must not overlap with any of the
575  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
576  * read_extent_tree_block(), ext4_split_extent_at(),
577  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
578  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
579  * caching the extents when reading from the extent tree while a
580  * truncate or punch hole operation is in progress.
581  */
582 #define EXT4_EX_NOCACHE				0x40000000
583 #define EXT4_EX_FORCE_CACHE			0x20000000
584 
585 /*
586  * Flags used by ext4_free_blocks
587  */
588 #define EXT4_FREE_BLOCKS_METADATA	0x0001
589 #define EXT4_FREE_BLOCKS_FORGET		0x0002
590 #define EXT4_FREE_BLOCKS_VALIDATED	0x0004
591 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE	0x0008
592 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
593 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
594 
595 /* Encryption algorithms */
596 #define EXT4_ENCRYPTION_MODE_INVALID		0
597 #define EXT4_ENCRYPTION_MODE_AES_256_XTS	1
598 #define EXT4_ENCRYPTION_MODE_AES_256_GCM	2
599 #define EXT4_ENCRYPTION_MODE_AES_256_CBC	3
600 #define EXT4_ENCRYPTION_MODE_AES_256_CTS	4
601 
602 #include "ext4_crypto.h"
603 
604 /*
605  * ioctl commands
606  */
607 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
608 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
609 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
610 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
611 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
612 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
613 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
614 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
615 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
616 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
617 #define EXT4_IOC_MIGRATE		_IO('f', 9)
618  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
619  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
620 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
621 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
622 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
623 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
624 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
625 #define EXT4_IOC_SET_ENCRYPTION_POLICY	_IOR('f', 19, struct ext4_encryption_policy)
626 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	_IOW('f', 20, __u8[16])
627 #define EXT4_IOC_GET_ENCRYPTION_POLICY	_IOW('f', 21, struct ext4_encryption_policy)
628 
629 #ifndef FS_IOC_FSGETXATTR
630 /* Until the uapi changes get merged for project quota... */
631 
632 #define FS_IOC_FSGETXATTR		_IOR('X', 31, struct fsxattr)
633 #define FS_IOC_FSSETXATTR		_IOW('X', 32, struct fsxattr)
634 
635 /*
636  * Structure for FS_IOC_FSGETXATTR and FS_IOC_FSSETXATTR.
637  */
638 struct fsxattr {
639 	__u32		fsx_xflags;	/* xflags field value (get/set) */
640 	__u32		fsx_extsize;	/* extsize field value (get/set)*/
641 	__u32		fsx_nextents;	/* nextents field value (get)	*/
642 	__u32		fsx_projid;	/* project identifier (get/set) */
643 	unsigned char	fsx_pad[12];
644 };
645 
646 /*
647  * Flags for the fsx_xflags field
648  */
649 #define FS_XFLAG_REALTIME	0x00000001	/* data in realtime volume */
650 #define FS_XFLAG_PREALLOC	0x00000002	/* preallocated file extents */
651 #define FS_XFLAG_IMMUTABLE	0x00000008	/* file cannot be modified */
652 #define FS_XFLAG_APPEND		0x00000010	/* all writes append */
653 #define FS_XFLAG_SYNC		0x00000020	/* all writes synchronous */
654 #define FS_XFLAG_NOATIME	0x00000040	/* do not update access time */
655 #define FS_XFLAG_NODUMP		0x00000080	/* do not include in backups */
656 #define FS_XFLAG_RTINHERIT	0x00000100	/* create with rt bit set */
657 #define FS_XFLAG_PROJINHERIT	0x00000200	/* create with parents projid */
658 #define FS_XFLAG_NOSYMLINKS	0x00000400	/* disallow symlink creation */
659 #define FS_XFLAG_EXTSIZE	0x00000800	/* extent size allocator hint */
660 #define FS_XFLAG_EXTSZINHERIT	0x00001000	/* inherit inode extent size */
661 #define FS_XFLAG_NODEFRAG	0x00002000  	/* do not defragment */
662 #define FS_XFLAG_FILESTREAM	0x00004000	/* use filestream allocator */
663 #define FS_XFLAG_HASATTR	0x80000000	/* no DIFLAG for this */
664 #endif /* !defined(FS_IOC_FSGETXATTR) */
665 
666 #define EXT4_IOC_FSGETXATTR		FS_IOC_FSGETXATTR
667 #define EXT4_IOC_FSSETXATTR		FS_IOC_FSSETXATTR
668 
669 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
670 /*
671  * ioctl commands in 32 bit emulation
672  */
673 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
674 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
675 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
676 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
677 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
678 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
679 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
680 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
681 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
682 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
683 #endif
684 
685 /* Max physical block we can address w/o extents */
686 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
687 
688 /*
689  * Structure of an inode on the disk
690  */
691 struct ext4_inode {
692 	__le16	i_mode;		/* File mode */
693 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
694 	__le32	i_size_lo;	/* Size in bytes */
695 	__le32	i_atime;	/* Access time */
696 	__le32	i_ctime;	/* Inode Change time */
697 	__le32	i_mtime;	/* Modification time */
698 	__le32	i_dtime;	/* Deletion Time */
699 	__le16	i_gid;		/* Low 16 bits of Group Id */
700 	__le16	i_links_count;	/* Links count */
701 	__le32	i_blocks_lo;	/* Blocks count */
702 	__le32	i_flags;	/* File flags */
703 	union {
704 		struct {
705 			__le32  l_i_version;
706 		} linux1;
707 		struct {
708 			__u32  h_i_translator;
709 		} hurd1;
710 		struct {
711 			__u32  m_i_reserved1;
712 		} masix1;
713 	} osd1;				/* OS dependent 1 */
714 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
715 	__le32	i_generation;	/* File version (for NFS) */
716 	__le32	i_file_acl_lo;	/* File ACL */
717 	__le32	i_size_high;
718 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
719 	union {
720 		struct {
721 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
722 			__le16	l_i_file_acl_high;
723 			__le16	l_i_uid_high;	/* these 2 fields */
724 			__le16	l_i_gid_high;	/* were reserved2[0] */
725 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
726 			__le16	l_i_reserved;
727 		} linux2;
728 		struct {
729 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
730 			__u16	h_i_mode_high;
731 			__u16	h_i_uid_high;
732 			__u16	h_i_gid_high;
733 			__u32	h_i_author;
734 		} hurd2;
735 		struct {
736 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
737 			__le16	m_i_file_acl_high;
738 			__u32	m_i_reserved2[2];
739 		} masix2;
740 	} osd2;				/* OS dependent 2 */
741 	__le16	i_extra_isize;
742 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
743 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
744 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
745 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
746 	__le32  i_crtime;       /* File Creation time */
747 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
748 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
749 	__le32	i_projid;	/* Project ID */
750 };
751 
752 struct move_extent {
753 	__u32 reserved;		/* should be zero */
754 	__u32 donor_fd;		/* donor file descriptor */
755 	__u64 orig_start;	/* logical start offset in block for orig */
756 	__u64 donor_start;	/* logical start offset in block for donor */
757 	__u64 len;		/* block length to be moved */
758 	__u64 moved_len;	/* moved block length */
759 };
760 
761 #define EXT4_EPOCH_BITS 2
762 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
763 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
764 
765 /*
766  * Extended fields will fit into an inode if the filesystem was formatted
767  * with large inodes (-I 256 or larger) and there are not currently any EAs
768  * consuming all of the available space. For new inodes we always reserve
769  * enough space for the kernel's known extended fields, but for inodes
770  * created with an old kernel this might not have been the case. None of
771  * the extended inode fields is critical for correct filesystem operation.
772  * This macro checks if a certain field fits in the inode. Note that
773  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
774  */
775 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
776 	((offsetof(typeof(*ext4_inode), field) +	\
777 	  sizeof((ext4_inode)->field))			\
778 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
779 	    (einode)->i_extra_isize))			\
780 
781 /*
782  * We use an encoding that preserves the times for extra epoch "00":
783  *
784  * extra  msb of                         adjust for signed
785  * epoch  32-bit                         32-bit tv_sec to
786  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
787  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
788  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
789  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
790  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
791  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
792  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
793  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
794  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
795  *
796  * Note that previous versions of the kernel on 64-bit systems would
797  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
798  * 1970.  e2fsck will correct this, assuming that it is run on the
799  * affected filesystem before 2242.
800  */
801 
802 static inline __le32 ext4_encode_extra_time(struct timespec *time)
803 {
804 	u32 extra = sizeof(time->tv_sec) > 4 ?
805 		((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK : 0;
806 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
807 }
808 
809 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
810 {
811 	if (unlikely(sizeof(time->tv_sec) > 4 &&
812 			(extra & cpu_to_le32(EXT4_EPOCH_MASK)))) {
813 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,20,0)
814 		/* Handle legacy encoding of pre-1970 dates with epoch
815 		 * bits 1,1.  We assume that by kernel version 4.20,
816 		 * everyone will have run fsck over the affected
817 		 * filesystems to correct the problem.  (This
818 		 * backwards compatibility may be removed before this
819 		 * time, at the discretion of the ext4 developers.)
820 		 */
821 		u64 extra_bits = le32_to_cpu(extra) & EXT4_EPOCH_MASK;
822 		if (extra_bits == 3 && ((time->tv_sec) & 0x80000000) != 0)
823 			extra_bits = 0;
824 		time->tv_sec += extra_bits << 32;
825 #else
826 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
827 #endif
828 	}
829 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
830 }
831 
832 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)			       \
833 do {									       \
834 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	       \
835 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
836 		(raw_inode)->xtime ## _extra =				       \
837 				ext4_encode_extra_time(&(inode)->xtime);       \
838 } while (0)
839 
840 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
841 do {									       \
842 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
843 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
844 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
845 		(raw_inode)->xtime ## _extra =				       \
846 				ext4_encode_extra_time(&(einode)->xtime);      \
847 } while (0)
848 
849 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)			       \
850 do {									       \
851 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
852 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
853 		ext4_decode_extra_time(&(inode)->xtime,			       \
854 				       raw_inode->xtime ## _extra);	       \
855 	else								       \
856 		(inode)->xtime.tv_nsec = 0;				       \
857 } while (0)
858 
859 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
860 do {									       \
861 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
862 		(einode)->xtime.tv_sec = 				       \
863 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
864 	else								       \
865 		(einode)->xtime.tv_sec = 0;				       \
866 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
867 		ext4_decode_extra_time(&(einode)->xtime,		       \
868 				       raw_inode->xtime ## _extra);	       \
869 	else								       \
870 		(einode)->xtime.tv_nsec = 0;				       \
871 } while (0)
872 
873 #define i_disk_version osd1.linux1.l_i_version
874 
875 #if defined(__KERNEL__) || defined(__linux__)
876 #define i_reserved1	osd1.linux1.l_i_reserved1
877 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
878 #define i_blocks_high	osd2.linux2.l_i_blocks_high
879 #define i_uid_low	i_uid
880 #define i_gid_low	i_gid
881 #define i_uid_high	osd2.linux2.l_i_uid_high
882 #define i_gid_high	osd2.linux2.l_i_gid_high
883 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
884 
885 #elif defined(__GNU__)
886 
887 #define i_translator	osd1.hurd1.h_i_translator
888 #define i_uid_high	osd2.hurd2.h_i_uid_high
889 #define i_gid_high	osd2.hurd2.h_i_gid_high
890 #define i_author	osd2.hurd2.h_i_author
891 
892 #elif defined(__masix__)
893 
894 #define i_reserved1	osd1.masix1.m_i_reserved1
895 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
896 #define i_reserved2	osd2.masix2.m_i_reserved2
897 
898 #endif /* defined(__KERNEL__) || defined(__linux__) */
899 
900 #include "extents_status.h"
901 
902 /*
903  * fourth extended file system inode data in memory
904  */
905 struct ext4_inode_info {
906 	__le32	i_data[15];	/* unconverted */
907 	__u32	i_dtime;
908 	ext4_fsblk_t	i_file_acl;
909 
910 	/*
911 	 * i_block_group is the number of the block group which contains
912 	 * this file's inode.  Constant across the lifetime of the inode,
913 	 * it is ued for making block allocation decisions - we try to
914 	 * place a file's data blocks near its inode block, and new inodes
915 	 * near to their parent directory's inode.
916 	 */
917 	ext4_group_t	i_block_group;
918 	ext4_lblk_t	i_dir_start_lookup;
919 #if (BITS_PER_LONG < 64)
920 	unsigned long	i_state_flags;		/* Dynamic state flags */
921 #endif
922 	unsigned long	i_flags;
923 
924 	/*
925 	 * Extended attributes can be read independently of the main file
926 	 * data. Taking i_mutex even when reading would cause contention
927 	 * between readers of EAs and writers of regular file data, so
928 	 * instead we synchronize on xattr_sem when reading or changing
929 	 * EAs.
930 	 */
931 	struct rw_semaphore xattr_sem;
932 
933 	struct list_head i_orphan;	/* unlinked but open inodes */
934 
935 	/*
936 	 * i_disksize keeps track of what the inode size is ON DISK, not
937 	 * in memory.  During truncate, i_size is set to the new size by
938 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
939 	 * set i_disksize to 0 until the truncate is actually under way.
940 	 *
941 	 * The intent is that i_disksize always represents the blocks which
942 	 * are used by this file.  This allows recovery to restart truncate
943 	 * on orphans if we crash during truncate.  We actually write i_disksize
944 	 * into the on-disk inode when writing inodes out, instead of i_size.
945 	 *
946 	 * The only time when i_disksize and i_size may be different is when
947 	 * a truncate is in progress.  The only things which change i_disksize
948 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
949 	 */
950 	loff_t	i_disksize;
951 
952 	/*
953 	 * i_data_sem is for serialising ext4_truncate() against
954 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
955 	 * data tree are chopped off during truncate. We can't do that in
956 	 * ext4 because whenever we perform intermediate commits during
957 	 * truncate, the inode and all the metadata blocks *must* be in a
958 	 * consistent state which allows truncation of the orphans to restart
959 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
960 	 * by other means, so we have i_data_sem.
961 	 */
962 	struct rw_semaphore i_data_sem;
963 	/*
964 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
965 	 * operations. We have to make sure that new page cannot be faulted in
966 	 * a section of the inode that is being punched. We cannot easily use
967 	 * i_data_sem for this since we need protection for the whole punch
968 	 * operation and i_data_sem ranks below transaction start so we have
969 	 * to occasionally drop it.
970 	 */
971 	struct rw_semaphore i_mmap_sem;
972 	struct inode vfs_inode;
973 	struct jbd2_inode *jinode;
974 
975 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
976 
977 	/*
978 	 * File creation time. Its function is same as that of
979 	 * struct timespec i_{a,c,m}time in the generic inode.
980 	 */
981 	struct timespec i_crtime;
982 
983 	/* mballoc */
984 	struct list_head i_prealloc_list;
985 	spinlock_t i_prealloc_lock;
986 
987 	/* extents status tree */
988 	struct ext4_es_tree i_es_tree;
989 	rwlock_t i_es_lock;
990 	struct list_head i_es_list;
991 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
992 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
993 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
994 					   extents to shrink. Protected by
995 					   i_es_lock  */
996 
997 	/* ialloc */
998 	ext4_group_t	i_last_alloc_group;
999 
1000 	/* allocation reservation info for delalloc */
1001 	/* In case of bigalloc, these refer to clusters rather than blocks */
1002 	unsigned int i_reserved_data_blocks;
1003 	unsigned int i_reserved_meta_blocks;
1004 	unsigned int i_allocated_meta_blocks;
1005 	ext4_lblk_t i_da_metadata_calc_last_lblock;
1006 	int i_da_metadata_calc_len;
1007 
1008 	/* on-disk additional length */
1009 	__u16 i_extra_isize;
1010 
1011 	/* Indicate the inline data space. */
1012 	u16 i_inline_off;
1013 	u16 i_inline_size;
1014 
1015 #ifdef CONFIG_QUOTA
1016 	/* quota space reservation, managed internally by quota code */
1017 	qsize_t i_reserved_quota;
1018 #endif
1019 
1020 	/* Lock protecting lists below */
1021 	spinlock_t i_completed_io_lock;
1022 	/*
1023 	 * Completed IOs that need unwritten extents handling and have
1024 	 * transaction reserved
1025 	 */
1026 	struct list_head i_rsv_conversion_list;
1027 	/*
1028 	 * Completed IOs that need unwritten extents handling and don't have
1029 	 * transaction reserved
1030 	 */
1031 	atomic_t i_ioend_count;	/* Number of outstanding io_end structs */
1032 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1033 	struct work_struct i_rsv_conversion_work;
1034 
1035 	spinlock_t i_block_reservation_lock;
1036 
1037 	/*
1038 	 * Transactions that contain inode's metadata needed to complete
1039 	 * fsync and fdatasync, respectively.
1040 	 */
1041 	tid_t i_sync_tid;
1042 	tid_t i_datasync_tid;
1043 
1044 #ifdef CONFIG_QUOTA
1045 	struct dquot *i_dquot[MAXQUOTAS];
1046 #endif
1047 
1048 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1049 	__u32 i_csum_seed;
1050 
1051 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1052 	/* Encryption params */
1053 	struct ext4_crypt_info *i_crypt_info;
1054 #endif
1055 	kprojid_t i_projid;
1056 };
1057 
1058 /*
1059  * File system states
1060  */
1061 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1062 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1063 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1064 
1065 /*
1066  * Misc. filesystem flags
1067  */
1068 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1069 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1070 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1071 
1072 /*
1073  * Mount flags set via mount options or defaults
1074  */
1075 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1076 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1077 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1078 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1079 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1080 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1081 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1082 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1083 #ifdef CONFIG_FS_DAX
1084 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
1085 #else
1086 #define EXT4_MOUNT_DAX			0
1087 #endif
1088 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1089 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1090 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1091 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1092 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1093 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1094 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1095 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1096 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1097 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1098 #define EXT4_MOUNT_QUOTA		0x80000 /* Some quota option set */
1099 #define EXT4_MOUNT_USRQUOTA		0x100000 /* "old" user quota */
1100 #define EXT4_MOUNT_GRPQUOTA		0x200000 /* "old" group quota */
1101 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1102 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1103 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1104 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1105 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1106 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1107 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1108 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1109 
1110 /*
1111  * Mount flags set either automatically (could not be set by mount option)
1112  * based on per file system feature or property or in special cases such as
1113  * distinguishing between explicit mount option definition and default.
1114  */
1115 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1116 						      specified delalloc */
1117 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1118 						      size of blocksize * 8
1119 						      blocks */
1120 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1121 						      file systems */
1122 
1123 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1124 						specified journal checksum */
1125 
1126 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1127 						~EXT4_MOUNT_##opt
1128 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1129 						EXT4_MOUNT_##opt
1130 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1131 					 EXT4_MOUNT_##opt)
1132 
1133 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1134 						~EXT4_MOUNT2_##opt
1135 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1136 						EXT4_MOUNT2_##opt
1137 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1138 					 EXT4_MOUNT2_##opt)
1139 
1140 #define ext4_test_and_set_bit		__test_and_set_bit_le
1141 #define ext4_set_bit			__set_bit_le
1142 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1143 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1144 #define ext4_clear_bit			__clear_bit_le
1145 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1146 #define ext4_test_bit			test_bit_le
1147 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1148 #define ext4_find_next_bit		find_next_bit_le
1149 
1150 extern void ext4_set_bits(void *bm, int cur, int len);
1151 
1152 /*
1153  * Maximal mount counts between two filesystem checks
1154  */
1155 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1156 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1157 
1158 /*
1159  * Behaviour when detecting errors
1160  */
1161 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1162 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1163 #define EXT4_ERRORS_PANIC		3	/* Panic */
1164 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1165 
1166 /* Metadata checksum algorithm codes */
1167 #define EXT4_CRC32C_CHKSUM		1
1168 
1169 /*
1170  * Structure of the super block
1171  */
1172 struct ext4_super_block {
1173 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1174 	__le32	s_blocks_count_lo;	/* Blocks count */
1175 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1176 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1177 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1178 	__le32	s_first_data_block;	/* First Data Block */
1179 	__le32	s_log_block_size;	/* Block size */
1180 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1181 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1182 	__le32	s_clusters_per_group;	/* # Clusters per group */
1183 	__le32	s_inodes_per_group;	/* # Inodes per group */
1184 	__le32	s_mtime;		/* Mount time */
1185 /*30*/	__le32	s_wtime;		/* Write time */
1186 	__le16	s_mnt_count;		/* Mount count */
1187 	__le16	s_max_mnt_count;	/* Maximal mount count */
1188 	__le16	s_magic;		/* Magic signature */
1189 	__le16	s_state;		/* File system state */
1190 	__le16	s_errors;		/* Behaviour when detecting errors */
1191 	__le16	s_minor_rev_level;	/* minor revision level */
1192 /*40*/	__le32	s_lastcheck;		/* time of last check */
1193 	__le32	s_checkinterval;	/* max. time between checks */
1194 	__le32	s_creator_os;		/* OS */
1195 	__le32	s_rev_level;		/* Revision level */
1196 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1197 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1198 	/*
1199 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1200 	 *
1201 	 * Note: the difference between the compatible feature set and
1202 	 * the incompatible feature set is that if there is a bit set
1203 	 * in the incompatible feature set that the kernel doesn't
1204 	 * know about, it should refuse to mount the filesystem.
1205 	 *
1206 	 * e2fsck's requirements are more strict; if it doesn't know
1207 	 * about a feature in either the compatible or incompatible
1208 	 * feature set, it must abort and not try to meddle with
1209 	 * things it doesn't understand...
1210 	 */
1211 	__le32	s_first_ino;		/* First non-reserved inode */
1212 	__le16  s_inode_size;		/* size of inode structure */
1213 	__le16	s_block_group_nr;	/* block group # of this superblock */
1214 	__le32	s_feature_compat;	/* compatible feature set */
1215 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1216 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1217 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1218 /*78*/	char	s_volume_name[16];	/* volume name */
1219 /*88*/	char	s_last_mounted[64];	/* directory where last mounted */
1220 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1221 	/*
1222 	 * Performance hints.  Directory preallocation should only
1223 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1224 	 */
1225 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1226 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1227 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1228 	/*
1229 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1230 	 */
1231 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1232 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1233 	__le32	s_journal_dev;		/* device number of journal file */
1234 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1235 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1236 	__u8	s_def_hash_version;	/* Default hash version to use */
1237 	__u8	s_jnl_backup_type;
1238 	__le16  s_desc_size;		/* size of group descriptor */
1239 /*100*/	__le32	s_default_mount_opts;
1240 	__le32	s_first_meta_bg;	/* First metablock block group */
1241 	__le32	s_mkfs_time;		/* When the filesystem was created */
1242 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1243 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1244 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1245 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1246 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1247 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1248 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1249 	__le32	s_flags;		/* Miscellaneous flags */
1250 	__le16  s_raid_stride;		/* RAID stride */
1251 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1252 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1253 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1254 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1255 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1256 	__u8	s_encryption_level;	/* versioning level for encryption */
1257 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1258 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1259 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1260 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1261 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1262 					      snapshot's future use */
1263 	__le32	s_snapshot_list;	/* inode number of the head of the
1264 					   on-disk snapshot list */
1265 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1266 	__le32	s_error_count;		/* number of fs errors */
1267 	__le32	s_first_error_time;	/* first time an error happened */
1268 	__le32	s_first_error_ino;	/* inode involved in first error */
1269 	__le64	s_first_error_block;	/* block involved of first error */
1270 	__u8	s_first_error_func[32];	/* function where the error happened */
1271 	__le32	s_first_error_line;	/* line number where error happened */
1272 	__le32	s_last_error_time;	/* most recent time of an error */
1273 	__le32	s_last_error_ino;	/* inode involved in last error */
1274 	__le32	s_last_error_line;	/* line number where error happened */
1275 	__le64	s_last_error_block;	/* block involved of last error */
1276 	__u8	s_last_error_func[32];	/* function where the error happened */
1277 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1278 	__u8	s_mount_opts[64];
1279 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1280 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1281 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1282 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1283 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1284 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1285 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1286 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1287 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1288 	__le32	s_reserved[98];		/* Padding to the end of the block */
1289 	__le32	s_checksum;		/* crc32c(superblock) */
1290 };
1291 
1292 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1293 
1294 #ifdef __KERNEL__
1295 
1296 /*
1297  * run-time mount flags
1298  */
1299 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1300 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1301 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1302 
1303 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1304 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1305 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1306 #else
1307 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1308 #endif
1309 
1310 /* Number of quota types we support */
1311 #define EXT4_MAXQUOTAS 3
1312 
1313 /*
1314  * fourth extended-fs super-block data in memory
1315  */
1316 struct ext4_sb_info {
1317 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1318 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1319 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1320 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1321 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1322 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1323 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1324 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1325 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1326 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1327 	unsigned long s_overhead;  /* # of fs overhead clusters */
1328 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1329 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1330 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1331 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1332 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1333 	struct buffer_head **s_group_desc;
1334 	unsigned int s_mount_opt;
1335 	unsigned int s_mount_opt2;
1336 	unsigned int s_mount_flags;
1337 	unsigned int s_def_mount_opt;
1338 	ext4_fsblk_t s_sb_block;
1339 	atomic64_t s_resv_clusters;
1340 	kuid_t s_resuid;
1341 	kgid_t s_resgid;
1342 	unsigned short s_mount_state;
1343 	unsigned short s_pad;
1344 	int s_addr_per_block_bits;
1345 	int s_desc_per_block_bits;
1346 	int s_inode_size;
1347 	int s_first_ino;
1348 	unsigned int s_inode_readahead_blks;
1349 	unsigned int s_inode_goal;
1350 	spinlock_t s_next_gen_lock;
1351 	u32 s_next_generation;
1352 	u32 s_hash_seed[4];
1353 	int s_def_hash_version;
1354 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1355 	struct percpu_counter s_freeclusters_counter;
1356 	struct percpu_counter s_freeinodes_counter;
1357 	struct percpu_counter s_dirs_counter;
1358 	struct percpu_counter s_dirtyclusters_counter;
1359 	struct blockgroup_lock *s_blockgroup_lock;
1360 	struct proc_dir_entry *s_proc;
1361 	struct kobject s_kobj;
1362 	struct completion s_kobj_unregister;
1363 	struct super_block *s_sb;
1364 
1365 	/* Journaling */
1366 	struct journal_s *s_journal;
1367 	struct list_head s_orphan;
1368 	struct mutex s_orphan_lock;
1369 	unsigned long s_resize_flags;		/* Flags indicating if there
1370 						   is a resizer */
1371 	unsigned long s_commit_interval;
1372 	u32 s_max_batch_time;
1373 	u32 s_min_batch_time;
1374 	struct block_device *journal_bdev;
1375 #ifdef CONFIG_QUOTA
1376 	char *s_qf_names[EXT4_MAXQUOTAS];	/* Names of quota files with journalled quota */
1377 	int s_jquota_fmt;			/* Format of quota to use */
1378 #endif
1379 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1380 	struct rb_root system_blks;
1381 
1382 #ifdef EXTENTS_STATS
1383 	/* ext4 extents stats */
1384 	unsigned long s_ext_min;
1385 	unsigned long s_ext_max;
1386 	unsigned long s_depth_max;
1387 	spinlock_t s_ext_stats_lock;
1388 	unsigned long s_ext_blocks;
1389 	unsigned long s_ext_extents;
1390 #endif
1391 
1392 	/* for buddy allocator */
1393 	struct ext4_group_info ***s_group_info;
1394 	struct inode *s_buddy_cache;
1395 	spinlock_t s_md_lock;
1396 	unsigned short *s_mb_offsets;
1397 	unsigned int *s_mb_maxs;
1398 	unsigned int s_group_info_size;
1399 
1400 	/* tunables */
1401 	unsigned long s_stripe;
1402 	unsigned int s_mb_stream_request;
1403 	unsigned int s_mb_max_to_scan;
1404 	unsigned int s_mb_min_to_scan;
1405 	unsigned int s_mb_stats;
1406 	unsigned int s_mb_order2_reqs;
1407 	unsigned int s_mb_group_prealloc;
1408 	unsigned int s_max_dir_size_kb;
1409 	/* where last allocation was done - for stream allocation */
1410 	unsigned long s_mb_last_group;
1411 	unsigned long s_mb_last_start;
1412 
1413 	/* stats for buddy allocator */
1414 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1415 	atomic_t s_bal_success;	/* we found long enough chunks */
1416 	atomic_t s_bal_allocated;	/* in blocks */
1417 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1418 	atomic_t s_bal_goals;	/* goal hits */
1419 	atomic_t s_bal_breaks;	/* too long searches */
1420 	atomic_t s_bal_2orders;	/* 2^order hits */
1421 	spinlock_t s_bal_lock;
1422 	unsigned long s_mb_buddies_generated;
1423 	unsigned long long s_mb_generation_time;
1424 	atomic_t s_mb_lost_chunks;
1425 	atomic_t s_mb_preallocated;
1426 	atomic_t s_mb_discarded;
1427 	atomic_t s_lock_busy;
1428 
1429 	/* locality groups */
1430 	struct ext4_locality_group __percpu *s_locality_groups;
1431 
1432 	/* for write statistics */
1433 	unsigned long s_sectors_written_start;
1434 	u64 s_kbytes_written;
1435 
1436 	/* the size of zero-out chunk */
1437 	unsigned int s_extent_max_zeroout_kb;
1438 
1439 	unsigned int s_log_groups_per_flex;
1440 	struct flex_groups *s_flex_groups;
1441 	ext4_group_t s_flex_groups_allocated;
1442 
1443 	/* workqueue for reserved extent conversions (buffered io) */
1444 	struct workqueue_struct *rsv_conversion_wq;
1445 
1446 	/* timer for periodic error stats printing */
1447 	struct timer_list s_err_report;
1448 
1449 	/* Lazy inode table initialization info */
1450 	struct ext4_li_request *s_li_request;
1451 	/* Wait multiplier for lazy initialization thread */
1452 	unsigned int s_li_wait_mult;
1453 
1454 	/* Kernel thread for multiple mount protection */
1455 	struct task_struct *s_mmp_tsk;
1456 
1457 	/* record the last minlen when FITRIM is called. */
1458 	atomic_t s_last_trim_minblks;
1459 
1460 	/* Reference to checksum algorithm driver via cryptoapi */
1461 	struct crypto_shash *s_chksum_driver;
1462 
1463 	/* Precomputed FS UUID checksum for seeding other checksums */
1464 	__u32 s_csum_seed;
1465 
1466 	/* Reclaim extents from extent status tree */
1467 	struct shrinker s_es_shrinker;
1468 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1469 	long s_es_nr_inode;
1470 	struct ext4_es_stats s_es_stats;
1471 	struct mb_cache *s_mb_cache;
1472 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1473 
1474 	/* Ratelimit ext4 messages. */
1475 	struct ratelimit_state s_err_ratelimit_state;
1476 	struct ratelimit_state s_warning_ratelimit_state;
1477 	struct ratelimit_state s_msg_ratelimit_state;
1478 };
1479 
1480 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1481 {
1482 	return sb->s_fs_info;
1483 }
1484 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1485 {
1486 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1487 }
1488 
1489 static inline struct timespec ext4_current_time(struct inode *inode)
1490 {
1491 	return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1492 		current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1493 }
1494 
1495 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1496 {
1497 	return ino == EXT4_ROOT_INO ||
1498 		ino == EXT4_USR_QUOTA_INO ||
1499 		ino == EXT4_GRP_QUOTA_INO ||
1500 		ino == EXT4_BOOT_LOADER_INO ||
1501 		ino == EXT4_JOURNAL_INO ||
1502 		ino == EXT4_RESIZE_INO ||
1503 		(ino >= EXT4_FIRST_INO(sb) &&
1504 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1505 }
1506 
1507 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1508 					      struct ext4_io_end *io_end)
1509 {
1510 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1511 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
1512 		atomic_inc(&EXT4_I(inode)->i_unwritten);
1513 	}
1514 }
1515 
1516 static inline ext4_io_end_t *ext4_inode_aio(struct inode *inode)
1517 {
1518 	return inode->i_private;
1519 }
1520 
1521 static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
1522 {
1523 	inode->i_private = io;
1524 }
1525 
1526 /*
1527  * Inode dynamic state flags
1528  */
1529 enum {
1530 	EXT4_STATE_JDATA,		/* journaled data exists */
1531 	EXT4_STATE_NEW,			/* inode is newly created */
1532 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1533 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1534 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1535 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1536 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1537 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1538 	EXT4_STATE_DIOREAD_LOCK,	/* Disable support for dio read
1539 					   nolocking */
1540 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1541 	EXT4_STATE_ORDERED_MODE,	/* data=ordered mode */
1542 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1543 };
1544 
1545 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1546 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1547 {									\
1548 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1549 }									\
1550 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1551 {									\
1552 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1553 }									\
1554 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1555 {									\
1556 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1557 }
1558 
1559 /* Add these declarations here only so that these functions can be
1560  * found by name.  Otherwise, they are very hard to locate. */
1561 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1562 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1563 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1564 EXT4_INODE_BIT_FNS(flag, flags, 0)
1565 
1566 /* Add these declarations here only so that these functions can be
1567  * found by name.  Otherwise, they are very hard to locate. */
1568 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1569 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1570 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1571 #if (BITS_PER_LONG < 64)
1572 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1573 
1574 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1575 {
1576 	(ei)->i_state_flags = 0;
1577 }
1578 #else
1579 EXT4_INODE_BIT_FNS(state, flags, 32)
1580 
1581 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1582 {
1583 	/* We depend on the fact that callers will set i_flags */
1584 }
1585 #endif
1586 #else
1587 /* Assume that user mode programs are passing in an ext4fs superblock, not
1588  * a kernel struct super_block.  This will allow us to call the feature-test
1589  * macros from user land. */
1590 #define EXT4_SB(sb)	(sb)
1591 #endif
1592 
1593 /*
1594  * Returns true if the inode is inode is encrypted
1595  */
1596 static inline int ext4_encrypted_inode(struct inode *inode)
1597 {
1598 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1599 	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
1600 #else
1601 	return 0;
1602 #endif
1603 }
1604 
1605 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1606 
1607 /*
1608  * Codes for operating systems
1609  */
1610 #define EXT4_OS_LINUX		0
1611 #define EXT4_OS_HURD		1
1612 #define EXT4_OS_MASIX		2
1613 #define EXT4_OS_FREEBSD		3
1614 #define EXT4_OS_LITES		4
1615 
1616 /*
1617  * Revision levels
1618  */
1619 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1620 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1621 
1622 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1623 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1624 
1625 #define EXT4_GOOD_OLD_INODE_SIZE 128
1626 
1627 /*
1628  * Feature set definitions
1629  */
1630 
1631 /* Use the ext4_{has,set,clear}_feature_* helpers; these will be removed */
1632 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)			\
1633 	((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1634 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)			\
1635 	((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1636 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)			\
1637 	((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1638 #define EXT4_SET_COMPAT_FEATURE(sb,mask)			\
1639 	EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1640 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)			\
1641 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1642 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)			\
1643 	EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1644 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)			\
1645 	EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1646 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
1647 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1648 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
1649 	EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1650 
1651 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1652 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1653 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1654 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1655 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1656 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1657 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1658 
1659 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1660 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1661 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1662 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1663 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1664 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1665 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1666 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1667 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1668 /*
1669  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1670  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1671  * all other data structures' checksums.  However, the METADATA_CSUM and
1672  * GDT_CSUM bits are mutually exclusive.
1673  */
1674 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1675 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1676 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1677 
1678 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1679 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1680 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1681 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1682 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1683 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1684 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1685 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1686 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1687 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1688 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1689 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1690 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1691 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1692 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1693 
1694 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1695 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1696 { \
1697 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1698 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1699 } \
1700 static inline void ext4_set_feature_##name(struct super_block *sb) \
1701 { \
1702 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1703 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1704 } \
1705 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1706 { \
1707 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1708 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1709 }
1710 
1711 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1712 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1713 { \
1714 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1715 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1716 } \
1717 static inline void ext4_set_feature_##name(struct super_block *sb) \
1718 { \
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_SB(sb)->s_es->s_feature_incompat |= \
1737 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1738 } \
1739 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1740 { \
1741 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1742 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1743 }
1744 
1745 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1746 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1747 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1748 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1749 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1750 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1751 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1752 
1753 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1754 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1755 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1756 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1757 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1758 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1759 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1760 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1761 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1762 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1763 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1764 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1765 
1766 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1767 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
1768 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
1769 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
1770 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
1771 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
1772 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
1773 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
1774 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
1775 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
1776 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
1777 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
1778 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
1779 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
1780 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
1781 
1782 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1783 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1784 					 EXT4_FEATURE_INCOMPAT_META_BG)
1785 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1786 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1787 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1788 
1789 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1790 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1791 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1792 					 EXT4_FEATURE_INCOMPAT_META_BG)
1793 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1794 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1795 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1796 
1797 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1798 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1799 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1800 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1801 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1802 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1803 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1804 					 EXT4_FEATURE_INCOMPAT_MMP | \
1805 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1806 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1807 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED)
1808 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1809 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1810 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1811 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1812 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1813 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1814 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1815 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1816 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1817 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
1818 					 EXT4_FEATURE_RO_COMPAT_PROJECT)
1819 
1820 #define EXTN_FEATURE_FUNCS(ver) \
1821 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1822 { \
1823 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1824 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1825 } \
1826 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1827 { \
1828 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1829 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1830 } \
1831 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1832 { \
1833 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1834 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1835 }
1836 
1837 EXTN_FEATURE_FUNCS(2)
1838 EXTN_FEATURE_FUNCS(3)
1839 EXTN_FEATURE_FUNCS(4)
1840 
1841 static inline bool ext4_has_compat_features(struct super_block *sb)
1842 {
1843 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1844 }
1845 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1846 {
1847 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1848 }
1849 static inline bool ext4_has_incompat_features(struct super_block *sb)
1850 {
1851 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
1852 }
1853 
1854 /*
1855  * Default values for user and/or group using reserved blocks
1856  */
1857 #define	EXT4_DEF_RESUID		0
1858 #define	EXT4_DEF_RESGID		0
1859 
1860 /*
1861  * Default project ID
1862  */
1863 #define	EXT4_DEF_PROJID		0
1864 
1865 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1866 
1867 /*
1868  * Default mount options
1869  */
1870 #define EXT4_DEFM_DEBUG		0x0001
1871 #define EXT4_DEFM_BSDGROUPS	0x0002
1872 #define EXT4_DEFM_XATTR_USER	0x0004
1873 #define EXT4_DEFM_ACL		0x0008
1874 #define EXT4_DEFM_UID16		0x0010
1875 #define EXT4_DEFM_JMODE		0x0060
1876 #define EXT4_DEFM_JMODE_DATA	0x0020
1877 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1878 #define EXT4_DEFM_JMODE_WBACK	0x0060
1879 #define EXT4_DEFM_NOBARRIER	0x0100
1880 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1881 #define EXT4_DEFM_DISCARD	0x0400
1882 #define EXT4_DEFM_NODELALLOC	0x0800
1883 
1884 /*
1885  * Default journal batch times
1886  */
1887 #define EXT4_DEF_MIN_BATCH_TIME	0
1888 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1889 
1890 /*
1891  * Minimum number of groups in a flexgroup before we separate out
1892  * directories into the first block group of a flexgroup
1893  */
1894 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1895 
1896 /*
1897  * Structure of a directory entry
1898  */
1899 #define EXT4_NAME_LEN 255
1900 
1901 struct ext4_dir_entry {
1902 	__le32	inode;			/* Inode number */
1903 	__le16	rec_len;		/* Directory entry length */
1904 	__le16	name_len;		/* Name length */
1905 	char	name[EXT4_NAME_LEN];	/* File name */
1906 };
1907 
1908 /*
1909  * The new version of the directory entry.  Since EXT4 structures are
1910  * stored in intel byte order, and the name_len field could never be
1911  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1912  * file_type field.
1913  */
1914 struct ext4_dir_entry_2 {
1915 	__le32	inode;			/* Inode number */
1916 	__le16	rec_len;		/* Directory entry length */
1917 	__u8	name_len;		/* Name length */
1918 	__u8	file_type;
1919 	char	name[EXT4_NAME_LEN];	/* File name */
1920 };
1921 
1922 /*
1923  * This is a bogus directory entry at the end of each leaf block that
1924  * records checksums.
1925  */
1926 struct ext4_dir_entry_tail {
1927 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1928 	__le16	det_rec_len;		/* 12 */
1929 	__u8	det_reserved_zero2;	/* Zero name length */
1930 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1931 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1932 };
1933 
1934 #define EXT4_DIRENT_TAIL(block, blocksize) \
1935 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1936 					((blocksize) - \
1937 					 sizeof(struct ext4_dir_entry_tail))))
1938 
1939 /*
1940  * Ext4 directory file types.  Only the low 3 bits are used.  The
1941  * other bits are reserved for now.
1942  */
1943 #define EXT4_FT_UNKNOWN		0
1944 #define EXT4_FT_REG_FILE	1
1945 #define EXT4_FT_DIR		2
1946 #define EXT4_FT_CHRDEV		3
1947 #define EXT4_FT_BLKDEV		4
1948 #define EXT4_FT_FIFO		5
1949 #define EXT4_FT_SOCK		6
1950 #define EXT4_FT_SYMLINK		7
1951 
1952 #define EXT4_FT_MAX		8
1953 
1954 #define EXT4_FT_DIR_CSUM	0xDE
1955 
1956 /*
1957  * EXT4_DIR_PAD defines the directory entries boundaries
1958  *
1959  * NOTE: It must be a multiple of 4
1960  */
1961 #define EXT4_DIR_PAD			4
1962 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1963 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1964 					 ~EXT4_DIR_ROUND)
1965 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1966 
1967 /*
1968  * If we ever get support for fs block sizes > page_size, we'll need
1969  * to remove the #if statements in the next two functions...
1970  */
1971 static inline unsigned int
1972 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1973 {
1974 	unsigned len = le16_to_cpu(dlen);
1975 
1976 #if (PAGE_CACHE_SIZE >= 65536)
1977 	if (len == EXT4_MAX_REC_LEN || len == 0)
1978 		return blocksize;
1979 	return (len & 65532) | ((len & 3) << 16);
1980 #else
1981 	return len;
1982 #endif
1983 }
1984 
1985 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1986 {
1987 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1988 		BUG();
1989 #if (PAGE_CACHE_SIZE >= 65536)
1990 	if (len < 65536)
1991 		return cpu_to_le16(len);
1992 	if (len == blocksize) {
1993 		if (blocksize == 65536)
1994 			return cpu_to_le16(EXT4_MAX_REC_LEN);
1995 		else
1996 			return cpu_to_le16(0);
1997 	}
1998 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1999 #else
2000 	return cpu_to_le16(len);
2001 #endif
2002 }
2003 
2004 /*
2005  * Hash Tree Directory indexing
2006  * (c) Daniel Phillips, 2001
2007  */
2008 
2009 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2010 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2011 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
2012 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2013 
2014 /* Legal values for the dx_root hash_version field: */
2015 
2016 #define DX_HASH_LEGACY		0
2017 #define DX_HASH_HALF_MD4	1
2018 #define DX_HASH_TEA		2
2019 #define DX_HASH_LEGACY_UNSIGNED	3
2020 #define DX_HASH_HALF_MD4_UNSIGNED	4
2021 #define DX_HASH_TEA_UNSIGNED		5
2022 
2023 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2024 			      const void *address, unsigned int length)
2025 {
2026 	struct {
2027 		struct shash_desc shash;
2028 		char ctx[4];
2029 	} desc;
2030 	int err;
2031 
2032 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2033 
2034 	desc.shash.tfm = sbi->s_chksum_driver;
2035 	desc.shash.flags = 0;
2036 	*(u32 *)desc.ctx = crc;
2037 
2038 	err = crypto_shash_update(&desc.shash, address, length);
2039 	BUG_ON(err);
2040 
2041 	return *(u32 *)desc.ctx;
2042 }
2043 
2044 #ifdef __KERNEL__
2045 
2046 /* hash info structure used by the directory hash */
2047 struct dx_hash_info
2048 {
2049 	u32		hash;
2050 	u32		minor_hash;
2051 	int		hash_version;
2052 	u32		*seed;
2053 };
2054 
2055 
2056 /* 32 and 64 bit signed EOF for dx directories */
2057 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2058 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2059 
2060 
2061 /*
2062  * Control parameters used by ext4_htree_next_block
2063  */
2064 #define HASH_NB_ALWAYS		1
2065 
2066 struct ext4_filename {
2067 	const struct qstr *usr_fname;
2068 	struct ext4_str disk_name;
2069 	struct dx_hash_info hinfo;
2070 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2071 	struct ext4_str crypto_buf;
2072 #endif
2073 };
2074 
2075 #define fname_name(p) ((p)->disk_name.name)
2076 #define fname_len(p)  ((p)->disk_name.len)
2077 
2078 /*
2079  * Describe an inode's exact location on disk and in memory
2080  */
2081 struct ext4_iloc
2082 {
2083 	struct buffer_head *bh;
2084 	unsigned long offset;
2085 	ext4_group_t block_group;
2086 };
2087 
2088 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2089 {
2090 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2091 }
2092 
2093 /*
2094  * This structure is stuffed into the struct file's private_data field
2095  * for directories.  It is where we put information so that we can do
2096  * readdir operations in hash tree order.
2097  */
2098 struct dir_private_info {
2099 	struct rb_root	root;
2100 	struct rb_node	*curr_node;
2101 	struct fname	*extra_fname;
2102 	loff_t		last_pos;
2103 	__u32		curr_hash;
2104 	__u32		curr_minor_hash;
2105 	__u32		next_hash;
2106 };
2107 
2108 /* calculate the first block number of the group */
2109 static inline ext4_fsblk_t
2110 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2111 {
2112 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2113 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2114 }
2115 
2116 /*
2117  * Special error return code only used by dx_probe() and its callers.
2118  */
2119 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2120 
2121 /*
2122  * Timeout and state flag for lazy initialization inode thread.
2123  */
2124 #define EXT4_DEF_LI_WAIT_MULT			10
2125 #define EXT4_DEF_LI_MAX_START_DELAY		5
2126 #define EXT4_LAZYINIT_QUIT			0x0001
2127 #define EXT4_LAZYINIT_RUNNING			0x0002
2128 
2129 /*
2130  * Lazy inode table initialization info
2131  */
2132 struct ext4_lazy_init {
2133 	unsigned long		li_state;
2134 	struct list_head	li_request_list;
2135 	struct mutex		li_list_mtx;
2136 };
2137 
2138 struct ext4_li_request {
2139 	struct super_block	*lr_super;
2140 	struct ext4_sb_info	*lr_sbi;
2141 	ext4_group_t		lr_next_group;
2142 	struct list_head	lr_request;
2143 	unsigned long		lr_next_sched;
2144 	unsigned long		lr_timeout;
2145 };
2146 
2147 struct ext4_features {
2148 	struct kobject f_kobj;
2149 	struct completion f_kobj_unregister;
2150 };
2151 
2152 /*
2153  * This structure will be used for multiple mount protection. It will be
2154  * written into the block number saved in the s_mmp_block field in the
2155  * superblock. Programs that check MMP should assume that if
2156  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2157  * to use the filesystem, regardless of how old the timestamp is.
2158  */
2159 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2160 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2161 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2162 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2163 
2164 struct mmp_struct {
2165 	__le32	mmp_magic;		/* Magic number for MMP */
2166 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2167 
2168 	/*
2169 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2170 	 * purposes and do not affect the correctness of the algorithm
2171 	 */
2172 	__le64	mmp_time;		/* Time last updated */
2173 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2174 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2175 
2176 	/*
2177 	 * mmp_check_interval is used to verify if the MMP block has been
2178 	 * updated on the block device. The value is updated based on the
2179 	 * maximum time to write the MMP block during an update cycle.
2180 	 */
2181 	__le16	mmp_check_interval;
2182 
2183 	__le16	mmp_pad1;
2184 	__le32	mmp_pad2[226];
2185 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2186 };
2187 
2188 /* arguments passed to the mmp thread */
2189 struct mmpd_data {
2190 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2191 	struct super_block *sb;  /* super block of the fs */
2192 };
2193 
2194 /*
2195  * Check interval multiplier
2196  * The MMP block is written every update interval and initially checked every
2197  * update interval x the multiplier (the value is then adapted based on the
2198  * write latency). The reason is that writes can be delayed under load and we
2199  * don't want readers to incorrectly assume that the filesystem is no longer
2200  * in use.
2201  */
2202 #define EXT4_MMP_CHECK_MULT		2UL
2203 
2204 /*
2205  * Minimum interval for MMP checking in seconds.
2206  */
2207 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2208 
2209 /*
2210  * Maximum interval for MMP checking in seconds.
2211  */
2212 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2213 
2214 /*
2215  * Function prototypes
2216  */
2217 
2218 /*
2219  * Ok, these declarations are also in <linux/kernel.h> but none of the
2220  * ext4 source programs needs to include it so they are duplicated here.
2221  */
2222 # define NORET_TYPE	/**/
2223 # define ATTRIB_NORET	__attribute__((noreturn))
2224 # define NORET_AND	noreturn,
2225 
2226 /* bitmap.c */
2227 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2228 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2229 				struct ext4_group_desc *gdp,
2230 				struct buffer_head *bh, int sz);
2231 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2232 				  struct ext4_group_desc *gdp,
2233 				  struct buffer_head *bh, int sz);
2234 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2235 				struct ext4_group_desc *gdp,
2236 				struct buffer_head *bh);
2237 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2238 				  struct ext4_group_desc *gdp,
2239 				  struct buffer_head *bh);
2240 
2241 /* balloc.c */
2242 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2243 					 ext4_fsblk_t blocknr,
2244 					 ext4_group_t *blockgrpp,
2245 					 ext4_grpblk_t *offsetp);
2246 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2247 					  ext4_fsblk_t block);
2248 
2249 extern unsigned int ext4_block_group(struct super_block *sb,
2250 			ext4_fsblk_t blocknr);
2251 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2252 			ext4_fsblk_t blocknr);
2253 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2254 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2255 			ext4_group_t group);
2256 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2257 					 ext4_fsblk_t goal,
2258 					 unsigned int flags,
2259 					 unsigned long *count,
2260 					 int *errp);
2261 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2262 				    s64 nclusters, unsigned int flags);
2263 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2264 extern void ext4_check_blocks_bitmap(struct super_block *);
2265 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2266 						    ext4_group_t block_group,
2267 						    struct buffer_head ** bh);
2268 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2269 
2270 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2271 						ext4_group_t block_group);
2272 extern int ext4_wait_block_bitmap(struct super_block *sb,
2273 				  ext4_group_t block_group,
2274 				  struct buffer_head *bh);
2275 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2276 						  ext4_group_t block_group);
2277 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2278 					      ext4_group_t block_group,
2279 					      struct ext4_group_desc *gdp);
2280 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2281 
2282 /* crypto_policy.c */
2283 int ext4_is_child_context_consistent_with_parent(struct inode *parent,
2284 						 struct inode *child);
2285 int ext4_inherit_context(struct inode *parent, struct inode *child);
2286 void ext4_to_hex(char *dst, char *src, size_t src_size);
2287 int ext4_process_policy(const struct ext4_encryption_policy *policy,
2288 			struct inode *inode);
2289 int ext4_get_policy(struct inode *inode,
2290 		    struct ext4_encryption_policy *policy);
2291 
2292 /* crypto.c */
2293 extern struct kmem_cache *ext4_crypt_info_cachep;
2294 bool ext4_valid_contents_enc_mode(uint32_t mode);
2295 uint32_t ext4_validate_encryption_key_size(uint32_t mode, uint32_t size);
2296 extern struct workqueue_struct *ext4_read_workqueue;
2297 struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode);
2298 void ext4_release_crypto_ctx(struct ext4_crypto_ctx *ctx);
2299 void ext4_restore_control_page(struct page *data_page);
2300 struct page *ext4_encrypt(struct inode *inode,
2301 			  struct page *plaintext_page);
2302 int ext4_decrypt(struct page *page);
2303 int ext4_encrypted_zeroout(struct inode *inode, ext4_lblk_t lblk,
2304 			   ext4_fsblk_t pblk, ext4_lblk_t len);
2305 extern const struct dentry_operations ext4_encrypted_d_ops;
2306 
2307 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2308 int ext4_init_crypto(void);
2309 void ext4_exit_crypto(void);
2310 static inline int ext4_sb_has_crypto(struct super_block *sb)
2311 {
2312 	return ext4_has_feature_encrypt(sb);
2313 }
2314 #else
2315 static inline int ext4_init_crypto(void) { return 0; }
2316 static inline void ext4_exit_crypto(void) { }
2317 static inline int ext4_sb_has_crypto(struct super_block *sb)
2318 {
2319 	return 0;
2320 }
2321 #endif
2322 
2323 /* crypto_fname.c */
2324 bool ext4_valid_filenames_enc_mode(uint32_t mode);
2325 u32 ext4_fname_crypto_round_up(u32 size, u32 blksize);
2326 unsigned ext4_fname_encrypted_size(struct inode *inode, u32 ilen);
2327 int ext4_fname_crypto_alloc_buffer(struct inode *inode,
2328 				   u32 ilen, struct ext4_str *crypto_str);
2329 int _ext4_fname_disk_to_usr(struct inode *inode,
2330 			    struct dx_hash_info *hinfo,
2331 			    const struct ext4_str *iname,
2332 			    struct ext4_str *oname);
2333 int ext4_fname_disk_to_usr(struct inode *inode,
2334 			   struct dx_hash_info *hinfo,
2335 			   const struct ext4_dir_entry_2 *de,
2336 			   struct ext4_str *oname);
2337 int ext4_fname_usr_to_disk(struct inode *inode,
2338 			   const struct qstr *iname,
2339 			   struct ext4_str *oname);
2340 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2341 void ext4_fname_crypto_free_buffer(struct ext4_str *crypto_str);
2342 int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
2343 			      int lookup, struct ext4_filename *fname);
2344 void ext4_fname_free_filename(struct ext4_filename *fname);
2345 #else
2346 static inline
2347 int ext4_setup_fname_crypto(struct inode *inode)
2348 {
2349 	return 0;
2350 }
2351 static inline void ext4_fname_crypto_free_buffer(struct ext4_str *p) { }
2352 static inline int ext4_fname_setup_filename(struct inode *dir,
2353 				     const struct qstr *iname,
2354 				     int lookup, struct ext4_filename *fname)
2355 {
2356 	fname->usr_fname = iname;
2357 	fname->disk_name.name = (unsigned char *) iname->name;
2358 	fname->disk_name.len = iname->len;
2359 	return 0;
2360 }
2361 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2362 #endif
2363 
2364 
2365 /* crypto_key.c */
2366 void ext4_free_crypt_info(struct ext4_crypt_info *ci);
2367 void ext4_free_encryption_info(struct inode *inode, struct ext4_crypt_info *ci);
2368 int _ext4_get_encryption_info(struct inode *inode);
2369 
2370 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2371 int ext4_has_encryption_key(struct inode *inode);
2372 
2373 static inline int ext4_get_encryption_info(struct inode *inode)
2374 {
2375 	struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
2376 
2377 	if (!ci ||
2378 	    (ci->ci_keyring_key &&
2379 	     (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
2380 					   (1 << KEY_FLAG_REVOKED) |
2381 					   (1 << KEY_FLAG_DEAD)))))
2382 		return _ext4_get_encryption_info(inode);
2383 	return 0;
2384 }
2385 
2386 static inline struct ext4_crypt_info *ext4_encryption_info(struct inode *inode)
2387 {
2388 	return EXT4_I(inode)->i_crypt_info;
2389 }
2390 
2391 #else
2392 static inline int ext4_has_encryption_key(struct inode *inode)
2393 {
2394 	return 0;
2395 }
2396 static inline int ext4_get_encryption_info(struct inode *inode)
2397 {
2398 	return 0;
2399 }
2400 static inline struct ext4_crypt_info *ext4_encryption_info(struct inode *inode)
2401 {
2402 	return NULL;
2403 }
2404 #endif
2405 
2406 
2407 /* dir.c */
2408 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2409 				  struct file *,
2410 				  struct ext4_dir_entry_2 *,
2411 				  struct buffer_head *, char *, int,
2412 				  unsigned int);
2413 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2414 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2415 					(de), (bh), (buf), (size), (offset)))
2416 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2417 				__u32 minor_hash,
2418 				struct ext4_dir_entry_2 *dirent,
2419 				struct ext4_str *ent_name);
2420 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2421 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2422 			     struct buffer_head *bh,
2423 			     void *buf, int buf_size,
2424 			     struct ext4_filename *fname,
2425 			     struct ext4_dir_entry_2 **dest_de);
2426 int ext4_insert_dentry(struct inode *dir,
2427 		       struct inode *inode,
2428 		       struct ext4_dir_entry_2 *de,
2429 		       int buf_size,
2430 		       struct ext4_filename *fname);
2431 static inline void ext4_update_dx_flag(struct inode *inode)
2432 {
2433 	if (!ext4_has_feature_dir_index(inode->i_sb))
2434 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2435 }
2436 static unsigned char ext4_filetype_table[] = {
2437 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2438 };
2439 
2440 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2441 {
2442 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2443 		return DT_UNKNOWN;
2444 
2445 	return ext4_filetype_table[filetype];
2446 }
2447 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2448 			     void *buf, int buf_size);
2449 
2450 /* fsync.c */
2451 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2452 
2453 /* hash.c */
2454 extern int ext4fs_dirhash(const char *name, int len, struct
2455 			  dx_hash_info *hinfo);
2456 
2457 /* ialloc.c */
2458 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2459 				      const struct qstr *qstr, __u32 goal,
2460 				      uid_t *owner, int handle_type,
2461 				      unsigned int line_no, int nblocks);
2462 
2463 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner) \
2464 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2465 			 0, 0, 0)
2466 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2467 				    type, nblocks)		    \
2468 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2469 			 (type), __LINE__, (nblocks))
2470 
2471 
2472 extern void ext4_free_inode(handle_t *, struct inode *);
2473 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2474 extern unsigned long ext4_count_free_inodes(struct super_block *);
2475 extern unsigned long ext4_count_dirs(struct super_block *);
2476 extern void ext4_check_inodes_bitmap(struct super_block *);
2477 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2478 extern int ext4_init_inode_table(struct super_block *sb,
2479 				 ext4_group_t group, int barrier);
2480 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2481 
2482 /* mballoc.c */
2483 extern const struct file_operations ext4_seq_mb_groups_fops;
2484 extern long ext4_mb_stats;
2485 extern long ext4_mb_max_to_scan;
2486 extern int ext4_mb_init(struct super_block *);
2487 extern int ext4_mb_release(struct super_block *);
2488 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2489 				struct ext4_allocation_request *, int *);
2490 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2491 extern void ext4_discard_preallocations(struct inode *);
2492 extern int __init ext4_init_mballoc(void);
2493 extern void ext4_exit_mballoc(void);
2494 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2495 			     struct buffer_head *bh, ext4_fsblk_t block,
2496 			     unsigned long count, int flags);
2497 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2498 				   ext4_group_t ngroups);
2499 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2500 		ext4_group_t i, struct ext4_group_desc *desc);
2501 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2502 				ext4_fsblk_t block, unsigned long count);
2503 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2504 
2505 /* inode.c */
2506 int ext4_inode_is_fast_symlink(struct inode *inode);
2507 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2508 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2509 int ext4_get_block_write(struct inode *inode, sector_t iblock,
2510 			 struct buffer_head *bh_result, int create);
2511 int ext4_dax_mmap_get_block(struct inode *inode, sector_t iblock,
2512 			    struct buffer_head *bh_result, int create);
2513 int ext4_get_block(struct inode *inode, sector_t iblock,
2514 				struct buffer_head *bh_result, int create);
2515 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2516 			   struct buffer_head *bh, int create);
2517 int ext4_walk_page_buffers(handle_t *handle,
2518 			   struct buffer_head *head,
2519 			   unsigned from,
2520 			   unsigned to,
2521 			   int *partial,
2522 			   int (*fn)(handle_t *handle,
2523 				     struct buffer_head *bh));
2524 int do_journal_get_write_access(handle_t *handle,
2525 				struct buffer_head *bh);
2526 #define FALL_BACK_TO_NONDELALLOC 1
2527 #define CONVERT_INLINE_DATA	 2
2528 
2529 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2530 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
2531 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2532 extern int  ext4_setattr(struct dentry *, struct iattr *);
2533 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2534 				struct kstat *stat);
2535 extern void ext4_evict_inode(struct inode *);
2536 extern void ext4_clear_inode(struct inode *);
2537 extern int  ext4_sync_inode(handle_t *, struct inode *);
2538 extern void ext4_dirty_inode(struct inode *, int);
2539 extern int ext4_change_inode_journal_flag(struct inode *, int);
2540 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2541 extern int ext4_inode_attach_jinode(struct inode *inode);
2542 extern int ext4_can_truncate(struct inode *inode);
2543 extern void ext4_truncate(struct inode *);
2544 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2545 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2546 extern void ext4_set_inode_flags(struct inode *);
2547 extern void ext4_get_inode_flags(struct ext4_inode_info *);
2548 extern int ext4_alloc_da_blocks(struct inode *inode);
2549 extern void ext4_set_aops(struct inode *inode);
2550 extern int ext4_writepage_trans_blocks(struct inode *);
2551 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2552 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2553 			     loff_t lstart, loff_t lend);
2554 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2555 extern int ext4_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf);
2556 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2557 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2558 extern void ext4_da_update_reserve_space(struct inode *inode,
2559 					int used, int quota_claim);
2560 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2561 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2562 
2563 /* indirect.c */
2564 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2565 				struct ext4_map_blocks *map, int flags);
2566 extern ssize_t ext4_ind_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
2567 				  loff_t offset);
2568 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2569 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2570 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2571 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2572 				 ext4_lblk_t start, ext4_lblk_t end);
2573 
2574 /* ioctl.c */
2575 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2576 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2577 
2578 /* migrate.c */
2579 extern int ext4_ext_migrate(struct inode *);
2580 extern int ext4_ind_migrate(struct inode *inode);
2581 
2582 /* namei.c */
2583 extern int ext4_dirent_csum_verify(struct inode *inode,
2584 				   struct ext4_dir_entry *dirent);
2585 extern int ext4_orphan_add(handle_t *, struct inode *);
2586 extern int ext4_orphan_del(handle_t *, struct inode *);
2587 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2588 				__u32 start_minor_hash, __u32 *next_hash);
2589 extern int ext4_search_dir(struct buffer_head *bh,
2590 			   char *search_buf,
2591 			   int buf_size,
2592 			   struct inode *dir,
2593 			   struct ext4_filename *fname,
2594 			   const struct qstr *d_name,
2595 			   unsigned int offset,
2596 			   struct ext4_dir_entry_2 **res_dir);
2597 extern int ext4_generic_delete_entry(handle_t *handle,
2598 				     struct inode *dir,
2599 				     struct ext4_dir_entry_2 *de_del,
2600 				     struct buffer_head *bh,
2601 				     void *entry_buf,
2602 				     int buf_size,
2603 				     int csum_size);
2604 extern int ext4_empty_dir(struct inode *inode);
2605 
2606 /* resize.c */
2607 extern int ext4_group_add(struct super_block *sb,
2608 				struct ext4_new_group_data *input);
2609 extern int ext4_group_extend(struct super_block *sb,
2610 				struct ext4_super_block *es,
2611 				ext4_fsblk_t n_blocks_count);
2612 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2613 
2614 /* super.c */
2615 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2616 extern int ext4_calculate_overhead(struct super_block *sb);
2617 extern void ext4_superblock_csum_set(struct super_block *sb);
2618 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2619 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2620 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2621 				    ext4_group_t ngroup);
2622 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2623 				     char nbuf[16]);
2624 
2625 extern __printf(4, 5)
2626 void __ext4_error(struct super_block *, const char *, unsigned int,
2627 		  const char *, ...);
2628 extern __printf(5, 6)
2629 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2630 		      const char *, ...);
2631 extern __printf(5, 6)
2632 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2633 		     const char *, ...);
2634 extern void __ext4_std_error(struct super_block *, const char *,
2635 			     unsigned int, int);
2636 extern __printf(4, 5)
2637 void __ext4_abort(struct super_block *, const char *, unsigned int,
2638 		  const char *, ...);
2639 extern __printf(4, 5)
2640 void __ext4_warning(struct super_block *, const char *, unsigned int,
2641 		    const char *, ...);
2642 extern __printf(4, 5)
2643 void __ext4_warning_inode(const struct inode *inode, const char *function,
2644 			  unsigned int line, const char *fmt, ...);
2645 extern __printf(3, 4)
2646 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2647 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2648 			   const char *, unsigned int, const char *);
2649 extern __printf(7, 8)
2650 void __ext4_grp_locked_error(const char *, unsigned int,
2651 			     struct super_block *, ext4_group_t,
2652 			     unsigned long, ext4_fsblk_t,
2653 			     const char *, ...);
2654 
2655 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2656 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2657 
2658 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
2659 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2660 
2661 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2662 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2663 
2664 #ifdef CONFIG_PRINTK
2665 
2666 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2667 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2668 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2669 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2670 #define ext4_error(sb, fmt, ...)					\
2671 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2672 #define ext4_abort(sb, fmt, ...)					\
2673 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2674 #define ext4_warning(sb, fmt, ...)					\
2675 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2676 #define ext4_warning_inode(inode, fmt, ...)				\
2677 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2678 #define ext4_msg(sb, level, fmt, ...)				\
2679 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2680 #define dump_mmp_msg(sb, mmp, msg)					\
2681 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2682 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2683 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2684 				fmt, ##__VA_ARGS__)
2685 
2686 #else
2687 
2688 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2689 do {									\
2690 	no_printk(fmt, ##__VA_ARGS__);					\
2691 	__ext4_error_inode(inode, "", 0, block, " ");			\
2692 } while (0)
2693 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2694 do {									\
2695 	no_printk(fmt, ##__VA_ARGS__);					\
2696 	__ext4_error_file(file, "", 0, block, " ");			\
2697 } while (0)
2698 #define ext4_error(sb, fmt, ...)					\
2699 do {									\
2700 	no_printk(fmt, ##__VA_ARGS__);					\
2701 	__ext4_error(sb, "", 0, " ");					\
2702 } while (0)
2703 #define ext4_abort(sb, fmt, ...)					\
2704 do {									\
2705 	no_printk(fmt, ##__VA_ARGS__);					\
2706 	__ext4_abort(sb, "", 0, " ");					\
2707 } while (0)
2708 #define ext4_warning(sb, fmt, ...)					\
2709 do {									\
2710 	no_printk(fmt, ##__VA_ARGS__);					\
2711 	__ext4_warning(sb, "", 0, " ");					\
2712 } while (0)
2713 #define ext4_warning_inode(inode, fmt, ...)				\
2714 do {									\
2715 	no_printk(fmt, ##__VA_ARGS__);					\
2716 	__ext4_warning_inode(inode, "", 0, " ");			\
2717 } while (0)
2718 #define ext4_msg(sb, level, fmt, ...)					\
2719 do {									\
2720 	no_printk(fmt, ##__VA_ARGS__);					\
2721 	__ext4_msg(sb, "", " ");					\
2722 } while (0)
2723 #define dump_mmp_msg(sb, mmp, msg)					\
2724 	__dump_mmp_msg(sb, mmp, "", 0, "")
2725 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2726 do {									\
2727 	no_printk(fmt, ##__VA_ARGS__);				\
2728 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2729 } while (0)
2730 
2731 #endif
2732 
2733 extern void ext4_update_dynamic_rev(struct super_block *sb);
2734 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2735 					__u32 compat);
2736 extern int ext4_update_rocompat_feature(handle_t *handle,
2737 					struct super_block *sb,	__u32 rocompat);
2738 extern int ext4_update_incompat_feature(handle_t *handle,
2739 					struct super_block *sb,	__u32 incompat);
2740 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2741 				      struct ext4_group_desc *bg);
2742 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2743 				      struct ext4_group_desc *bg);
2744 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2745 				     struct ext4_group_desc *bg);
2746 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2747 				      struct ext4_group_desc *bg);
2748 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2749 				 struct ext4_group_desc *bg);
2750 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2751 				struct ext4_group_desc *bg);
2752 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2753 				   struct ext4_group_desc *bg);
2754 extern void ext4_block_bitmap_set(struct super_block *sb,
2755 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2756 extern void ext4_inode_bitmap_set(struct super_block *sb,
2757 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2758 extern void ext4_inode_table_set(struct super_block *sb,
2759 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2760 extern void ext4_free_group_clusters_set(struct super_block *sb,
2761 					 struct ext4_group_desc *bg,
2762 					 __u32 count);
2763 extern void ext4_free_inodes_set(struct super_block *sb,
2764 				struct ext4_group_desc *bg, __u32 count);
2765 extern void ext4_used_dirs_set(struct super_block *sb,
2766 				struct ext4_group_desc *bg, __u32 count);
2767 extern void ext4_itable_unused_set(struct super_block *sb,
2768 				   struct ext4_group_desc *bg, __u32 count);
2769 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2770 				       struct ext4_group_desc *gdp);
2771 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2772 				     struct ext4_group_desc *gdp);
2773 extern int ext4_register_li_request(struct super_block *sb,
2774 				    ext4_group_t first_not_zeroed);
2775 
2776 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2777 {
2778 	return ext4_has_feature_gdt_csum(sb) ||
2779 	       EXT4_SB(sb)->s_chksum_driver != NULL;
2780 }
2781 
2782 static inline int ext4_has_metadata_csum(struct super_block *sb)
2783 {
2784 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2785 		     !EXT4_SB(sb)->s_chksum_driver);
2786 
2787 	return (EXT4_SB(sb)->s_chksum_driver != NULL);
2788 }
2789 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2790 {
2791 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2792 		le32_to_cpu(es->s_blocks_count_lo);
2793 }
2794 
2795 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2796 {
2797 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2798 		le32_to_cpu(es->s_r_blocks_count_lo);
2799 }
2800 
2801 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2802 {
2803 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2804 		le32_to_cpu(es->s_free_blocks_count_lo);
2805 }
2806 
2807 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2808 					 ext4_fsblk_t blk)
2809 {
2810 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2811 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2812 }
2813 
2814 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2815 					      ext4_fsblk_t blk)
2816 {
2817 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2818 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2819 }
2820 
2821 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2822 					   ext4_fsblk_t blk)
2823 {
2824 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2825 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2826 }
2827 
2828 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2829 {
2830 	if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2831 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2832 			le32_to_cpu(raw_inode->i_size_lo);
2833 	else
2834 		return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2835 }
2836 
2837 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2838 {
2839 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2840 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2841 }
2842 
2843 static inline
2844 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2845 					    ext4_group_t group)
2846 {
2847 	 struct ext4_group_info ***grp_info;
2848 	 long indexv, indexh;
2849 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2850 	 grp_info = EXT4_SB(sb)->s_group_info;
2851 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2852 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2853 	 return grp_info[indexv][indexh];
2854 }
2855 
2856 /*
2857  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2858  * the locking protocol documented in the comments of ext4_group_add()
2859  * in resize.c
2860  */
2861 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2862 {
2863 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2864 
2865 	smp_rmb();
2866 	return ngroups;
2867 }
2868 
2869 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2870 					     ext4_group_t block_group)
2871 {
2872 	return block_group >> sbi->s_log_groups_per_flex;
2873 }
2874 
2875 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2876 {
2877 	return 1 << sbi->s_log_groups_per_flex;
2878 }
2879 
2880 #define ext4_std_error(sb, errno)				\
2881 do {								\
2882 	if ((errno))						\
2883 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2884 } while (0)
2885 
2886 #ifdef CONFIG_SMP
2887 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2888  * counters. So we need to make sure we have free clusters more
2889  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2890  */
2891 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2892 #else
2893 #define EXT4_FREECLUSTERS_WATERMARK 0
2894 #endif
2895 
2896 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2897 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2898 {
2899 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2900 		     !inode_is_locked(inode));
2901 	down_write(&EXT4_I(inode)->i_data_sem);
2902 	if (newsize > EXT4_I(inode)->i_disksize)
2903 		EXT4_I(inode)->i_disksize = newsize;
2904 	up_write(&EXT4_I(inode)->i_data_sem);
2905 }
2906 
2907 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2908 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2909 {
2910 	int changed = 0;
2911 
2912 	if (newsize > inode->i_size) {
2913 		i_size_write(inode, newsize);
2914 		changed = 1;
2915 	}
2916 	if (newsize > EXT4_I(inode)->i_disksize) {
2917 		ext4_update_i_disksize(inode, newsize);
2918 		changed |= 2;
2919 	}
2920 	return changed;
2921 }
2922 
2923 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2924 				      loff_t len);
2925 
2926 struct ext4_group_info {
2927 	unsigned long   bb_state;
2928 	struct rb_root  bb_free_root;
2929 	ext4_grpblk_t	bb_first_free;	/* first free block */
2930 	ext4_grpblk_t	bb_free;	/* total free blocks */
2931 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2932 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2933 	struct          list_head bb_prealloc_list;
2934 #ifdef DOUBLE_CHECK
2935 	void            *bb_bitmap;
2936 #endif
2937 	struct rw_semaphore alloc_sem;
2938 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2939 					 * regions, index is order.
2940 					 * bb_counters[3] = 5 means
2941 					 * 5 free 8-block regions. */
2942 };
2943 
2944 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2945 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2946 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2947 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2948 
2949 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2950 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2951 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2952 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2953 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2954 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2955 
2956 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2957 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2958 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2959 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2960 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2961 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2962 
2963 #define EXT4_MAX_CONTENTION		8
2964 #define EXT4_CONTENTION_THRESHOLD	2
2965 
2966 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2967 					      ext4_group_t group)
2968 {
2969 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2970 }
2971 
2972 /*
2973  * Returns true if the filesystem is busy enough that attempts to
2974  * access the block group locks has run into contention.
2975  */
2976 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2977 {
2978 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2979 }
2980 
2981 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2982 {
2983 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2984 	if (spin_trylock(lock))
2985 		/*
2986 		 * We're able to grab the lock right away, so drop the
2987 		 * lock contention counter.
2988 		 */
2989 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2990 	else {
2991 		/*
2992 		 * The lock is busy, so bump the contention counter,
2993 		 * and then wait on the spin lock.
2994 		 */
2995 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2996 				  EXT4_MAX_CONTENTION);
2997 		spin_lock(lock);
2998 	}
2999 }
3000 
3001 static inline void ext4_unlock_group(struct super_block *sb,
3002 					ext4_group_t group)
3003 {
3004 	spin_unlock(ext4_group_lock_ptr(sb, group));
3005 }
3006 
3007 /*
3008  * Block validity checking
3009  */
3010 #define ext4_check_indirect_blockref(inode, bh)				\
3011 	ext4_check_blockref(__func__, __LINE__, inode,			\
3012 			    (__le32 *)(bh)->b_data,			\
3013 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3014 
3015 #define ext4_ind_check_inode(inode)					\
3016 	ext4_check_blockref(__func__, __LINE__, inode,			\
3017 			    EXT4_I(inode)->i_data,			\
3018 			    EXT4_NDIR_BLOCKS)
3019 
3020 /*
3021  * Inodes and files operations
3022  */
3023 
3024 /* dir.c */
3025 extern const struct file_operations ext4_dir_operations;
3026 
3027 /* file.c */
3028 extern const struct inode_operations ext4_file_inode_operations;
3029 extern const struct file_operations ext4_file_operations;
3030 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
3031 
3032 /* inline.c */
3033 extern int ext4_get_max_inline_size(struct inode *inode);
3034 extern int ext4_find_inline_data_nolock(struct inode *inode);
3035 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
3036 				 unsigned int len);
3037 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3038 
3039 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
3040 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3041 					 struct inode *inode,
3042 					 loff_t pos, unsigned len,
3043 					 unsigned flags,
3044 					 struct page **pagep);
3045 extern int ext4_write_inline_data_end(struct inode *inode,
3046 				      loff_t pos, unsigned len,
3047 				      unsigned copied,
3048 				      struct page *page);
3049 extern struct buffer_head *
3050 ext4_journalled_write_inline_data(struct inode *inode,
3051 				  unsigned len,
3052 				  struct page *page);
3053 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3054 					   struct inode *inode,
3055 					   loff_t pos, unsigned len,
3056 					   unsigned flags,
3057 					   struct page **pagep,
3058 					   void **fsdata);
3059 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3060 					 unsigned len, unsigned copied,
3061 					 struct page *page);
3062 extern int ext4_try_add_inline_entry(handle_t *handle,
3063 				     struct ext4_filename *fname,
3064 				     struct inode *dir, struct inode *inode);
3065 extern int ext4_try_create_inline_dir(handle_t *handle,
3066 				      struct inode *parent,
3067 				      struct inode *inode);
3068 extern int ext4_read_inline_dir(struct file *filp,
3069 				struct dir_context *ctx,
3070 				int *has_inline_data);
3071 extern int htree_inlinedir_to_tree(struct file *dir_file,
3072 				   struct inode *dir, ext4_lblk_t block,
3073 				   struct dx_hash_info *hinfo,
3074 				   __u32 start_hash, __u32 start_minor_hash,
3075 				   int *has_inline_data);
3076 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3077 					struct ext4_filename *fname,
3078 					const struct qstr *d_name,
3079 					struct ext4_dir_entry_2 **res_dir,
3080 					int *has_inline_data);
3081 extern int ext4_delete_inline_entry(handle_t *handle,
3082 				    struct inode *dir,
3083 				    struct ext4_dir_entry_2 *de_del,
3084 				    struct buffer_head *bh,
3085 				    int *has_inline_data);
3086 extern int empty_inline_dir(struct inode *dir, int *has_inline_data);
3087 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3088 					struct ext4_dir_entry_2 **parent_de,
3089 					int *retval);
3090 extern int ext4_inline_data_fiemap(struct inode *inode,
3091 				   struct fiemap_extent_info *fieinfo,
3092 				   int *has_inline, __u64 start, __u64 len);
3093 extern int ext4_try_to_evict_inline_data(handle_t *handle,
3094 					 struct inode *inode,
3095 					 int needed);
3096 extern void ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3097 
3098 extern int ext4_convert_inline_data(struct inode *inode);
3099 
3100 static inline int ext4_has_inline_data(struct inode *inode)
3101 {
3102 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3103 	       EXT4_I(inode)->i_inline_off;
3104 }
3105 
3106 /* namei.c */
3107 extern const struct inode_operations ext4_dir_inode_operations;
3108 extern const struct inode_operations ext4_special_inode_operations;
3109 extern struct dentry *ext4_get_parent(struct dentry *child);
3110 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3111 				 struct ext4_dir_entry_2 *de,
3112 				 int blocksize, int csum_size,
3113 				 unsigned int parent_ino, int dotdot_real_len);
3114 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
3115 				   unsigned int blocksize);
3116 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
3117 					 struct inode *inode,
3118 					 struct buffer_head *bh);
3119 #define S_SHIFT 12
3120 static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
3121 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3122 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3123 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3124 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3125 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3126 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3127 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3128 };
3129 
3130 static inline void ext4_set_de_type(struct super_block *sb,
3131 				struct ext4_dir_entry_2 *de,
3132 				umode_t mode) {
3133 	if (ext4_has_feature_filetype(sb))
3134 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3135 }
3136 
3137 /* readpages.c */
3138 extern int ext4_mpage_readpages(struct address_space *mapping,
3139 				struct list_head *pages, struct page *page,
3140 				unsigned nr_pages);
3141 
3142 /* symlink.c */
3143 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3144 extern const struct inode_operations ext4_symlink_inode_operations;
3145 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3146 
3147 /* sysfs.c */
3148 extern int ext4_register_sysfs(struct super_block *sb);
3149 extern void ext4_unregister_sysfs(struct super_block *sb);
3150 extern int __init ext4_init_sysfs(void);
3151 extern void ext4_exit_sysfs(void);
3152 
3153 /* block_validity */
3154 extern void ext4_release_system_zone(struct super_block *sb);
3155 extern int ext4_setup_system_zone(struct super_block *sb);
3156 extern int __init ext4_init_system_zone(void);
3157 extern void ext4_exit_system_zone(void);
3158 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3159 				 ext4_fsblk_t start_blk,
3160 				 unsigned int count);
3161 extern int ext4_check_blockref(const char *, unsigned int,
3162 			       struct inode *, __le32 *, unsigned int);
3163 
3164 /* extents.c */
3165 struct ext4_ext_path;
3166 struct ext4_extent;
3167 
3168 /*
3169  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3170  * __le32.
3171  */
3172 #define EXT_MAX_BLOCKS	0xffffffff
3173 
3174 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
3175 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
3176 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3177 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3178 			       struct ext4_map_blocks *map, int flags);
3179 extern void ext4_ext_truncate(handle_t *, struct inode *);
3180 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3181 				 ext4_lblk_t end);
3182 extern void ext4_ext_init(struct super_block *);
3183 extern void ext4_ext_release(struct super_block *);
3184 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3185 			  loff_t len);
3186 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3187 					  loff_t offset, ssize_t len);
3188 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3189 			   struct ext4_map_blocks *map, int flags);
3190 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
3191 					 ext4_lblk_t lblocks);
3192 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3193 						   int num,
3194 						   struct ext4_ext_path *path);
3195 extern int ext4_can_extents_be_merged(struct inode *inode,
3196 				      struct ext4_extent *ex1,
3197 				      struct ext4_extent *ex2);
3198 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3199 				  struct ext4_ext_path **,
3200 				  struct ext4_extent *, int);
3201 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3202 					      struct ext4_ext_path **,
3203 					      int flags);
3204 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3205 extern int ext4_ext_check_inode(struct inode *inode);
3206 extern int ext4_find_delalloc_range(struct inode *inode,
3207 				    ext4_lblk_t lblk_start,
3208 				    ext4_lblk_t lblk_end);
3209 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
3210 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3211 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3212 			__u64 start, __u64 len);
3213 extern int ext4_ext_precache(struct inode *inode);
3214 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
3215 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
3216 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3217 				struct inode *inode2, ext4_lblk_t lblk1,
3218 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3219 			     int mark_unwritten,int *err);
3220 
3221 /* move_extent.c */
3222 extern void ext4_double_down_write_data_sem(struct inode *first,
3223 					    struct inode *second);
3224 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3225 					  struct inode *donor_inode);
3226 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3227 			     __u64 start_orig, __u64 start_donor,
3228 			     __u64 len, __u64 *moved_len);
3229 
3230 /* page-io.c */
3231 extern int __init ext4_init_pageio(void);
3232 extern void ext4_exit_pageio(void);
3233 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3234 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3235 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3236 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3237 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3238 				struct writeback_control *wbc);
3239 extern void ext4_end_io_rsv_work(struct work_struct *work);
3240 extern void ext4_io_submit(struct ext4_io_submit *io);
3241 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3242 			       struct page *page,
3243 			       int len,
3244 			       struct writeback_control *wbc,
3245 			       bool keep_towrite);
3246 
3247 /* mmp.c */
3248 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3249 
3250 /*
3251  * Add new method to test whether block and inode bitmaps are properly
3252  * initialized. With uninit_bg reading the block from disk is not enough
3253  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3254  */
3255 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3256 
3257 static inline int bitmap_uptodate(struct buffer_head *bh)
3258 {
3259 	return (buffer_uptodate(bh) &&
3260 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3261 }
3262 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3263 {
3264 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3265 }
3266 
3267 /*
3268  * Disable DIO read nolock optimization, so new dioreaders will be forced
3269  * to grab i_mutex
3270  */
3271 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
3272 {
3273 	ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3274 	smp_mb();
3275 }
3276 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
3277 {
3278 	smp_mb();
3279 	ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3280 }
3281 
3282 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3283 
3284 /* For ioend & aio unwritten conversion wait queues */
3285 #define EXT4_WQ_HASH_SZ		37
3286 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3287 					    EXT4_WQ_HASH_SZ])
3288 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
3289 					     EXT4_WQ_HASH_SZ])
3290 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3291 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
3292 
3293 #define EXT4_RESIZING	0
3294 extern int ext4_resize_begin(struct super_block *sb);
3295 extern void ext4_resize_end(struct super_block *sb);
3296 
3297 #endif	/* __KERNEL__ */
3298 
3299 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3300 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3301 
3302 #endif	/* _EXT4_H */
3303