xref: /openbmc/linux/fs/ext4/ext4.h (revision 331573fe)
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/wait.h>
30 #include <linux/blockgroup_lock.h>
31 #include <linux/percpu_counter.h>
32 #include <linux/ratelimit.h>
33 #include <crypto/hash.h>
34 #include <linux/falloc.h>
35 #ifdef __KERNEL__
36 #include <linux/compat.h>
37 #endif
38 
39 /*
40  * The fourth extended filesystem constants/structures
41  */
42 
43 /*
44  * Define EXT4FS_DEBUG to produce debug messages
45  */
46 #undef EXT4FS_DEBUG
47 
48 /*
49  * Debug code
50  */
51 #ifdef EXT4FS_DEBUG
52 #define ext4_debug(f, a...)						\
53 	do {								\
54 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
55 			__FILE__, __LINE__, __func__);			\
56 		printk(KERN_DEBUG f, ## a);				\
57 	} while (0)
58 #else
59 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
60 #endif
61 
62 /*
63  * Turn on EXT_DEBUG to get lots of info about extents operations.
64  */
65 #define EXT_DEBUG__
66 #ifdef EXT_DEBUG
67 #define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
68 #else
69 #define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
70 #endif
71 
72 #define EXT4_ERROR_INODE(inode, fmt, a...) \
73 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
74 
75 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
76 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
77 
78 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
79 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
80 
81 /* data type for block offset of block group */
82 typedef int ext4_grpblk_t;
83 
84 /* data type for filesystem-wide blocks number */
85 typedef unsigned long long ext4_fsblk_t;
86 
87 /* data type for file logical block number */
88 typedef __u32 ext4_lblk_t;
89 
90 /* data type for block group number */
91 typedef unsigned int ext4_group_t;
92 
93 enum SHIFT_DIRECTION {
94 	SHIFT_LEFT = 0,
95 	SHIFT_RIGHT,
96 };
97 
98 /*
99  * Flags used in mballoc's allocation_context flags field.
100  *
101  * Also used to show what's going on for debugging purposes when the
102  * flag field is exported via the traceport interface
103  */
104 
105 /* prefer goal again. length */
106 #define EXT4_MB_HINT_MERGE		0x0001
107 /* blocks already reserved */
108 #define EXT4_MB_HINT_RESERVED		0x0002
109 /* metadata is being allocated */
110 #define EXT4_MB_HINT_METADATA		0x0004
111 /* first blocks in the file */
112 #define EXT4_MB_HINT_FIRST		0x0008
113 /* search for the best chunk */
114 #define EXT4_MB_HINT_BEST		0x0010
115 /* data is being allocated */
116 #define EXT4_MB_HINT_DATA		0x0020
117 /* don't preallocate (for tails) */
118 #define EXT4_MB_HINT_NOPREALLOC		0x0040
119 /* allocate for locality group */
120 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
121 /* allocate goal blocks or none */
122 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
123 /* goal is meaningful */
124 #define EXT4_MB_HINT_TRY_GOAL		0x0200
125 /* blocks already pre-reserved by delayed allocation */
126 #define EXT4_MB_DELALLOC_RESERVED	0x0400
127 /* We are doing stream allocation */
128 #define EXT4_MB_STREAM_ALLOC		0x0800
129 /* Use reserved root blocks if needed */
130 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
131 /* Use blocks from reserved pool */
132 #define EXT4_MB_USE_RESERVED		0x2000
133 
134 struct ext4_allocation_request {
135 	/* target inode for block we're allocating */
136 	struct inode *inode;
137 	/* how many blocks we want to allocate */
138 	unsigned int len;
139 	/* logical block in target inode */
140 	ext4_lblk_t logical;
141 	/* the closest logical allocated block to the left */
142 	ext4_lblk_t lleft;
143 	/* the closest logical allocated block to the right */
144 	ext4_lblk_t lright;
145 	/* phys. target (a hint) */
146 	ext4_fsblk_t goal;
147 	/* phys. block for the closest logical allocated block to the left */
148 	ext4_fsblk_t pleft;
149 	/* phys. block for the closest logical allocated block to the right */
150 	ext4_fsblk_t pright;
151 	/* flags. see above EXT4_MB_HINT_* */
152 	unsigned int flags;
153 };
154 
155 /*
156  * Logical to physical block mapping, used by ext4_map_blocks()
157  *
158  * This structure is used to pass requests into ext4_map_blocks() as
159  * well as to store the information returned by ext4_map_blocks().  It
160  * takes less room on the stack than a struct buffer_head.
161  */
162 #define EXT4_MAP_NEW		(1 << BH_New)
163 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
164 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
165 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
166 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
167 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
168 
169 struct ext4_map_blocks {
170 	ext4_fsblk_t m_pblk;
171 	ext4_lblk_t m_lblk;
172 	unsigned int m_len;
173 	unsigned int m_flags;
174 };
175 
176 /*
177  * Flags for ext4_io_end->flags
178  */
179 #define	EXT4_IO_END_UNWRITTEN	0x0001
180 
181 /*
182  * For converting unwritten extents on a work queue. 'handle' is used for
183  * buffered writeback.
184  */
185 typedef struct ext4_io_end {
186 	struct list_head	list;		/* per-file finished IO list */
187 	handle_t		*handle;	/* handle reserved for extent
188 						 * conversion */
189 	struct inode		*inode;		/* file being written to */
190 	struct bio		*bio;		/* Linked list of completed
191 						 * bios covering the extent */
192 	unsigned int		flag;		/* unwritten or not */
193 	loff_t			offset;		/* offset in the file */
194 	ssize_t			size;		/* size of the extent */
195 	atomic_t		count;		/* reference counter */
196 } ext4_io_end_t;
197 
198 struct ext4_io_submit {
199 	int			io_op;
200 	struct bio		*io_bio;
201 	ext4_io_end_t		*io_end;
202 	sector_t		io_next_block;
203 };
204 
205 /*
206  * Special inodes numbers
207  */
208 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
209 #define EXT4_ROOT_INO		 2	/* Root inode */
210 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
211 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
212 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
213 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
214 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
215 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
216 
217 /* First non-reserved inode for old ext4 filesystems */
218 #define EXT4_GOOD_OLD_FIRST_INO	11
219 
220 /*
221  * Maximal count of links to a file
222  */
223 #define EXT4_LINK_MAX		65000
224 
225 /*
226  * Macro-instructions used to manage several block sizes
227  */
228 #define EXT4_MIN_BLOCK_SIZE		1024
229 #define	EXT4_MAX_BLOCK_SIZE		65536
230 #define EXT4_MIN_BLOCK_LOG_SIZE		10
231 #define EXT4_MAX_BLOCK_LOG_SIZE		16
232 #ifdef __KERNEL__
233 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
234 #else
235 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
236 #endif
237 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
238 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
239 					 EXT4_SB(s)->s_cluster_bits)
240 #ifdef __KERNEL__
241 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
242 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
243 #else
244 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
245 #endif
246 #ifdef __KERNEL__
247 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
248 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
249 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
250 #else
251 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
252 				 EXT4_GOOD_OLD_INODE_SIZE : \
253 				 (s)->s_inode_size)
254 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
255 				 EXT4_GOOD_OLD_FIRST_INO : \
256 				 (s)->s_first_ino)
257 #endif
258 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
259 
260 /* Translate a block number to a cluster number */
261 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
262 /* Translate a cluster number to a block number */
263 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
264 /* Translate # of blks to # of clusters */
265 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
266 				 (sbi)->s_cluster_bits)
267 /* Mask out the low bits to get the starting block of the cluster */
268 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
269 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
270 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
271 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
272 /* Get the cluster offset */
273 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
274 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
275 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
276 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
277 
278 /*
279  * Structure of a blocks group descriptor
280  */
281 struct ext4_group_desc
282 {
283 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
284 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
285 	__le32	bg_inode_table_lo;	/* Inodes table block */
286 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
287 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
288 	__le16	bg_used_dirs_count_lo;	/* Directories count */
289 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
290 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
291 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
292 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
293 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
294 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
295 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
296 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
297 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
298 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
299 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
300 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
301 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
302 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
303 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
304 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
305 	__u32   bg_reserved;
306 };
307 
308 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
309 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
310 	 sizeof(__le16))
311 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
312 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
313 	 sizeof(__le16))
314 
315 /*
316  * Structure of a flex block group info
317  */
318 
319 struct flex_groups {
320 	atomic64_t	free_clusters;
321 	atomic_t	free_inodes;
322 	atomic_t	used_dirs;
323 };
324 
325 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
326 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
327 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
328 
329 /*
330  * Macro-instructions used to manage group descriptors
331  */
332 #define EXT4_MIN_DESC_SIZE		32
333 #define EXT4_MIN_DESC_SIZE_64BIT	64
334 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
335 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
336 #ifdef __KERNEL__
337 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
338 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
339 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
340 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
341 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
342 #else
343 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
344 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
345 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
346 #endif
347 
348 /*
349  * Constants relative to the data blocks
350  */
351 #define	EXT4_NDIR_BLOCKS		12
352 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
353 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
354 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
355 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
356 
357 /*
358  * Inode flags
359  */
360 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
361 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
362 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
363 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
364 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
365 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
366 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
367 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
368 /* Reserved for compression usage... */
369 #define EXT4_DIRTY_FL			0x00000100
370 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
371 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
372 	/* nb: was previously EXT2_ECOMPR_FL */
373 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
374 /* End compression flags --- maybe not all used */
375 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
376 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
377 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
378 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
379 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
380 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
381 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
382 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
383 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
384 #define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
385 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
386 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
387 
388 #define EXT4_FL_USER_VISIBLE		0x004BDFFF /* User visible flags */
389 #define EXT4_FL_USER_MODIFIABLE		0x004380FF /* User modifiable flags */
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 
397 /* Flags that are appropriate for regular files (all but dir-specific ones). */
398 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
399 
400 /* Flags that are appropriate for non-directories/regular files. */
401 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
402 
403 /* Mask out flags that are inappropriate for the given type of inode. */
404 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
405 {
406 	if (S_ISDIR(mode))
407 		return flags;
408 	else if (S_ISREG(mode))
409 		return flags & EXT4_REG_FLMASK;
410 	else
411 		return flags & EXT4_OTHER_FLMASK;
412 }
413 
414 /*
415  * Inode flags used for atomic set/get
416  */
417 enum {
418 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
419 	EXT4_INODE_UNRM		= 1,	/* Undelete */
420 	EXT4_INODE_COMPR	= 2,	/* Compress file */
421 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
422 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
423 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
424 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
425 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
426 /* Reserved for compression usage... */
427 	EXT4_INODE_DIRTY	= 8,
428 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
429 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
430 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
431 /* End compression flags --- maybe not all used */
432 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
433 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
434 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
435 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
436 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
437 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
438 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
439 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
440 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
441 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
442 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
443 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
444 };
445 
446 /*
447  * Since it's pretty easy to mix up bit numbers and hex values, we use a
448  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
449  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
450  * any extra space in the compiled kernel image, otherwise, the build will fail.
451  * It's important that these values are the same, since we are using
452  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
453  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
454  * values found in ext2, ext3 and ext4 filesystems, and of course the values
455  * defined in e2fsprogs.
456  *
457  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
458  */
459 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
460 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
461 
462 static inline void ext4_check_flag_values(void)
463 {
464 	CHECK_FLAG_VALUE(SECRM);
465 	CHECK_FLAG_VALUE(UNRM);
466 	CHECK_FLAG_VALUE(COMPR);
467 	CHECK_FLAG_VALUE(SYNC);
468 	CHECK_FLAG_VALUE(IMMUTABLE);
469 	CHECK_FLAG_VALUE(APPEND);
470 	CHECK_FLAG_VALUE(NODUMP);
471 	CHECK_FLAG_VALUE(NOATIME);
472 	CHECK_FLAG_VALUE(DIRTY);
473 	CHECK_FLAG_VALUE(COMPRBLK);
474 	CHECK_FLAG_VALUE(NOCOMPR);
475 	CHECK_FLAG_VALUE(ENCRYPT);
476 	CHECK_FLAG_VALUE(INDEX);
477 	CHECK_FLAG_VALUE(IMAGIC);
478 	CHECK_FLAG_VALUE(JOURNAL_DATA);
479 	CHECK_FLAG_VALUE(NOTAIL);
480 	CHECK_FLAG_VALUE(DIRSYNC);
481 	CHECK_FLAG_VALUE(TOPDIR);
482 	CHECK_FLAG_VALUE(HUGE_FILE);
483 	CHECK_FLAG_VALUE(EXTENTS);
484 	CHECK_FLAG_VALUE(EA_INODE);
485 	CHECK_FLAG_VALUE(EOFBLOCKS);
486 	CHECK_FLAG_VALUE(INLINE_DATA);
487 	CHECK_FLAG_VALUE(RESERVED);
488 }
489 
490 /* Used to pass group descriptor data when online resize is done */
491 struct ext4_new_group_input {
492 	__u32 group;		/* Group number for this data */
493 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
494 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
495 	__u64 inode_table;	/* Absolute block number of inode table start */
496 	__u32 blocks_count;	/* Total number of blocks in this group */
497 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
498 	__u16 unused;
499 };
500 
501 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
502 struct compat_ext4_new_group_input {
503 	u32 group;
504 	compat_u64 block_bitmap;
505 	compat_u64 inode_bitmap;
506 	compat_u64 inode_table;
507 	u32 blocks_count;
508 	u16 reserved_blocks;
509 	u16 unused;
510 };
511 #endif
512 
513 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
514 struct ext4_new_group_data {
515 	__u32 group;
516 	__u64 block_bitmap;
517 	__u64 inode_bitmap;
518 	__u64 inode_table;
519 	__u32 blocks_count;
520 	__u16 reserved_blocks;
521 	__u16 unused;
522 	__u32 free_blocks_count;
523 };
524 
525 /* Indexes used to index group tables in ext4_new_group_data */
526 enum {
527 	BLOCK_BITMAP = 0,	/* block bitmap */
528 	INODE_BITMAP,		/* inode bitmap */
529 	INODE_TABLE,		/* inode tables */
530 	GROUP_TABLE_COUNT,
531 };
532 
533 /*
534  * Flags used by ext4_map_blocks()
535  */
536 	/* Allocate any needed blocks and/or convert an unwritten
537 	   extent to be an initialized ext4 */
538 #define EXT4_GET_BLOCKS_CREATE			0x0001
539 	/* Request the creation of an unwritten extent */
540 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
541 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
542 						 EXT4_GET_BLOCKS_CREATE)
543 	/* Caller is from the delayed allocation writeout path
544 	 * finally doing the actual allocation of delayed blocks */
545 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
546 	/* caller is from the direct IO path, request to creation of an
547 	unwritten extents if not allocated, split the unwritten
548 	extent if blocks has been preallocated already*/
549 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
550 #define EXT4_GET_BLOCKS_CONVERT			0x0010
551 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
552 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
553 	/* Convert extent to initialized after IO complete */
554 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
555 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
556 	/* Eventual metadata allocation (due to growing extent tree)
557 	 * should not fail, so try to use reserved blocks for that.*/
558 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
559 	/* Don't normalize allocation size (used for fallocate) */
560 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
561 	/* Request will not result in inode size update (user for fallocate) */
562 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
563 	/* Do not take i_data_sem locking in ext4_map_blocks */
564 #define EXT4_GET_BLOCKS_NO_LOCK			0x0100
565 	/* Convert written extents to unwritten */
566 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0200
567 
568 /*
569  * The bit position of these flags must not overlap with any of the
570  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
571  * read_extent_tree_block(), ext4_split_extent_at(),
572  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
573  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
574  * caching the extents when reading from the extent tree while a
575  * truncate or punch hole operation is in progress.
576  */
577 #define EXT4_EX_NOCACHE				0x40000000
578 #define EXT4_EX_FORCE_CACHE			0x20000000
579 
580 /*
581  * Flags used by ext4_free_blocks
582  */
583 #define EXT4_FREE_BLOCKS_METADATA	0x0001
584 #define EXT4_FREE_BLOCKS_FORGET		0x0002
585 #define EXT4_FREE_BLOCKS_VALIDATED	0x0004
586 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE	0x0008
587 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
588 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
589 
590 /* Encryption algorithms */
591 #define EXT4_ENCRYPTION_MODE_INVALID		0
592 #define EXT4_ENCRYPTION_MODE_AES_256_XTS	1
593 #define EXT4_ENCRYPTION_MODE_AES_256_GCM	2
594 #define EXT4_ENCRYPTION_MODE_AES_256_CBC	3
595 #define EXT4_ENCRYPTION_MODE_AES_256_CTS	4
596 
597 #include "ext4_crypto.h"
598 
599 /*
600  * ioctl commands
601  */
602 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
603 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
604 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
605 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
606 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
607 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
608 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
609 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
610 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
611 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
612 #define EXT4_IOC_MIGRATE		_IO('f', 9)
613  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
614  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
615 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
616 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
617 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
618 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
619 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
620 #define EXT4_IOC_SET_ENCRYPTION_POLICY	_IOR('f', 19, struct ext4_encryption_policy)
621 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	_IOW('f', 20, __u8[16])
622 #define EXT4_IOC_GET_ENCRYPTION_POLICY	_IOW('f', 21, struct ext4_encryption_policy)
623 
624 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
625 /*
626  * ioctl commands in 32 bit emulation
627  */
628 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
629 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
630 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
631 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
632 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
633 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
634 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
635 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
636 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
637 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
638 #endif
639 
640 /* Max physical block we can address w/o extents */
641 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
642 
643 /*
644  * Structure of an inode on the disk
645  */
646 struct ext4_inode {
647 	__le16	i_mode;		/* File mode */
648 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
649 	__le32	i_size_lo;	/* Size in bytes */
650 	__le32	i_atime;	/* Access time */
651 	__le32	i_ctime;	/* Inode Change time */
652 	__le32	i_mtime;	/* Modification time */
653 	__le32	i_dtime;	/* Deletion Time */
654 	__le16	i_gid;		/* Low 16 bits of Group Id */
655 	__le16	i_links_count;	/* Links count */
656 	__le32	i_blocks_lo;	/* Blocks count */
657 	__le32	i_flags;	/* File flags */
658 	union {
659 		struct {
660 			__le32  l_i_version;
661 		} linux1;
662 		struct {
663 			__u32  h_i_translator;
664 		} hurd1;
665 		struct {
666 			__u32  m_i_reserved1;
667 		} masix1;
668 	} osd1;				/* OS dependent 1 */
669 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
670 	__le32	i_generation;	/* File version (for NFS) */
671 	__le32	i_file_acl_lo;	/* File ACL */
672 	__le32	i_size_high;
673 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
674 	union {
675 		struct {
676 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
677 			__le16	l_i_file_acl_high;
678 			__le16	l_i_uid_high;	/* these 2 fields */
679 			__le16	l_i_gid_high;	/* were reserved2[0] */
680 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
681 			__le16	l_i_reserved;
682 		} linux2;
683 		struct {
684 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
685 			__u16	h_i_mode_high;
686 			__u16	h_i_uid_high;
687 			__u16	h_i_gid_high;
688 			__u32	h_i_author;
689 		} hurd2;
690 		struct {
691 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
692 			__le16	m_i_file_acl_high;
693 			__u32	m_i_reserved2[2];
694 		} masix2;
695 	} osd2;				/* OS dependent 2 */
696 	__le16	i_extra_isize;
697 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
698 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
699 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
700 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
701 	__le32  i_crtime;       /* File Creation time */
702 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
703 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
704 };
705 
706 struct move_extent {
707 	__u32 reserved;		/* should be zero */
708 	__u32 donor_fd;		/* donor file descriptor */
709 	__u64 orig_start;	/* logical start offset in block for orig */
710 	__u64 donor_start;	/* logical start offset in block for donor */
711 	__u64 len;		/* block length to be moved */
712 	__u64 moved_len;	/* moved block length */
713 };
714 
715 #define EXT4_EPOCH_BITS 2
716 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
717 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
718 
719 /*
720  * Extended fields will fit into an inode if the filesystem was formatted
721  * with large inodes (-I 256 or larger) and there are not currently any EAs
722  * consuming all of the available space. For new inodes we always reserve
723  * enough space for the kernel's known extended fields, but for inodes
724  * created with an old kernel this might not have been the case. None of
725  * the extended inode fields is critical for correct filesystem operation.
726  * This macro checks if a certain field fits in the inode. Note that
727  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
728  */
729 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
730 	((offsetof(typeof(*ext4_inode), field) +	\
731 	  sizeof((ext4_inode)->field))			\
732 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
733 	    (einode)->i_extra_isize))			\
734 
735 static inline __le32 ext4_encode_extra_time(struct timespec *time)
736 {
737        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
738 			   (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
739                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
740 }
741 
742 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
743 {
744        if (sizeof(time->tv_sec) > 4)
745 	       time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
746 			       << 32;
747        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
748 }
749 
750 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)			       \
751 do {									       \
752 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	       \
753 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
754 		(raw_inode)->xtime ## _extra =				       \
755 				ext4_encode_extra_time(&(inode)->xtime);       \
756 } while (0)
757 
758 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
759 do {									       \
760 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
761 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
762 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
763 		(raw_inode)->xtime ## _extra =				       \
764 				ext4_encode_extra_time(&(einode)->xtime);      \
765 } while (0)
766 
767 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)			       \
768 do {									       \
769 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
770 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
771 		ext4_decode_extra_time(&(inode)->xtime,			       \
772 				       raw_inode->xtime ## _extra);	       \
773 	else								       \
774 		(inode)->xtime.tv_nsec = 0;				       \
775 } while (0)
776 
777 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
778 do {									       \
779 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
780 		(einode)->xtime.tv_sec = 				       \
781 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
782 	else								       \
783 		(einode)->xtime.tv_sec = 0;				       \
784 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
785 		ext4_decode_extra_time(&(einode)->xtime,		       \
786 				       raw_inode->xtime ## _extra);	       \
787 	else								       \
788 		(einode)->xtime.tv_nsec = 0;				       \
789 } while (0)
790 
791 #define i_disk_version osd1.linux1.l_i_version
792 
793 #if defined(__KERNEL__) || defined(__linux__)
794 #define i_reserved1	osd1.linux1.l_i_reserved1
795 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
796 #define i_blocks_high	osd2.linux2.l_i_blocks_high
797 #define i_uid_low	i_uid
798 #define i_gid_low	i_gid
799 #define i_uid_high	osd2.linux2.l_i_uid_high
800 #define i_gid_high	osd2.linux2.l_i_gid_high
801 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
802 
803 #elif defined(__GNU__)
804 
805 #define i_translator	osd1.hurd1.h_i_translator
806 #define i_uid_high	osd2.hurd2.h_i_uid_high
807 #define i_gid_high	osd2.hurd2.h_i_gid_high
808 #define i_author	osd2.hurd2.h_i_author
809 
810 #elif defined(__masix__)
811 
812 #define i_reserved1	osd1.masix1.m_i_reserved1
813 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
814 #define i_reserved2	osd2.masix2.m_i_reserved2
815 
816 #endif /* defined(__KERNEL__) || defined(__linux__) */
817 
818 #include "extents_status.h"
819 
820 /*
821  * fourth extended file system inode data in memory
822  */
823 struct ext4_inode_info {
824 	__le32	i_data[15];	/* unconverted */
825 	__u32	i_dtime;
826 	ext4_fsblk_t	i_file_acl;
827 
828 	/*
829 	 * i_block_group is the number of the block group which contains
830 	 * this file's inode.  Constant across the lifetime of the inode,
831 	 * it is ued for making block allocation decisions - we try to
832 	 * place a file's data blocks near its inode block, and new inodes
833 	 * near to their parent directory's inode.
834 	 */
835 	ext4_group_t	i_block_group;
836 	ext4_lblk_t	i_dir_start_lookup;
837 #if (BITS_PER_LONG < 64)
838 	unsigned long	i_state_flags;		/* Dynamic state flags */
839 #endif
840 	unsigned long	i_flags;
841 
842 	/*
843 	 * Extended attributes can be read independently of the main file
844 	 * data. Taking i_mutex even when reading would cause contention
845 	 * between readers of EAs and writers of regular file data, so
846 	 * instead we synchronize on xattr_sem when reading or changing
847 	 * EAs.
848 	 */
849 	struct rw_semaphore xattr_sem;
850 
851 	struct list_head i_orphan;	/* unlinked but open inodes */
852 
853 	/*
854 	 * i_disksize keeps track of what the inode size is ON DISK, not
855 	 * in memory.  During truncate, i_size is set to the new size by
856 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
857 	 * set i_disksize to 0 until the truncate is actually under way.
858 	 *
859 	 * The intent is that i_disksize always represents the blocks which
860 	 * are used by this file.  This allows recovery to restart truncate
861 	 * on orphans if we crash during truncate.  We actually write i_disksize
862 	 * into the on-disk inode when writing inodes out, instead of i_size.
863 	 *
864 	 * The only time when i_disksize and i_size may be different is when
865 	 * a truncate is in progress.  The only things which change i_disksize
866 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
867 	 */
868 	loff_t	i_disksize;
869 
870 	/*
871 	 * i_data_sem is for serialising ext4_truncate() against
872 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
873 	 * data tree are chopped off during truncate. We can't do that in
874 	 * ext4 because whenever we perform intermediate commits during
875 	 * truncate, the inode and all the metadata blocks *must* be in a
876 	 * consistent state which allows truncation of the orphans to restart
877 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
878 	 * by other means, so we have i_data_sem.
879 	 */
880 	struct rw_semaphore i_data_sem;
881 	struct inode vfs_inode;
882 	struct jbd2_inode *jinode;
883 
884 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
885 
886 	/*
887 	 * File creation time. Its function is same as that of
888 	 * struct timespec i_{a,c,m}time in the generic inode.
889 	 */
890 	struct timespec i_crtime;
891 
892 	/* mballoc */
893 	struct list_head i_prealloc_list;
894 	spinlock_t i_prealloc_lock;
895 
896 	/* extents status tree */
897 	struct ext4_es_tree i_es_tree;
898 	rwlock_t i_es_lock;
899 	struct list_head i_es_list;
900 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
901 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
902 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
903 					   extents to shrink. Protected by
904 					   i_es_lock  */
905 
906 	/* ialloc */
907 	ext4_group_t	i_last_alloc_group;
908 
909 	/* allocation reservation info for delalloc */
910 	/* In case of bigalloc, these refer to clusters rather than blocks */
911 	unsigned int i_reserved_data_blocks;
912 	unsigned int i_reserved_meta_blocks;
913 	unsigned int i_allocated_meta_blocks;
914 	ext4_lblk_t i_da_metadata_calc_last_lblock;
915 	int i_da_metadata_calc_len;
916 
917 	/* on-disk additional length */
918 	__u16 i_extra_isize;
919 
920 	/* Indicate the inline data space. */
921 	u16 i_inline_off;
922 	u16 i_inline_size;
923 
924 #ifdef CONFIG_QUOTA
925 	/* quota space reservation, managed internally by quota code */
926 	qsize_t i_reserved_quota;
927 #endif
928 
929 	/* Lock protecting lists below */
930 	spinlock_t i_completed_io_lock;
931 	/*
932 	 * Completed IOs that need unwritten extents handling and have
933 	 * transaction reserved
934 	 */
935 	struct list_head i_rsv_conversion_list;
936 	/*
937 	 * Completed IOs that need unwritten extents handling and don't have
938 	 * transaction reserved
939 	 */
940 	atomic_t i_ioend_count;	/* Number of outstanding io_end structs */
941 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
942 	struct work_struct i_rsv_conversion_work;
943 
944 	spinlock_t i_block_reservation_lock;
945 
946 	/*
947 	 * Transactions that contain inode's metadata needed to complete
948 	 * fsync and fdatasync, respectively.
949 	 */
950 	tid_t i_sync_tid;
951 	tid_t i_datasync_tid;
952 
953 #ifdef CONFIG_QUOTA
954 	struct dquot *i_dquot[MAXQUOTAS];
955 #endif
956 
957 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
958 	__u32 i_csum_seed;
959 
960 #ifdef CONFIG_EXT4_FS_ENCRYPTION
961 	/* Encryption params */
962 	struct ext4_crypt_info *i_crypt_info;
963 #endif
964 };
965 
966 /*
967  * File system states
968  */
969 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
970 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
971 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
972 
973 /*
974  * Misc. filesystem flags
975  */
976 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
977 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
978 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
979 
980 /*
981  * Mount flags set via mount options or defaults
982  */
983 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
984 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
985 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
986 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
987 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
988 #define EXT4_MOUNT_ERRORS_MASK		0x00070
989 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
990 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
991 #ifdef CONFIG_FS_DAX
992 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
993 #else
994 #define EXT4_MOUNT_DAX			0
995 #endif
996 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
997 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
998 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
999 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1000 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1001 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1002 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1003 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1004 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1005 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1006 #define EXT4_MOUNT_QUOTA		0x80000 /* Some quota option set */
1007 #define EXT4_MOUNT_USRQUOTA		0x100000 /* "old" user quota */
1008 #define EXT4_MOUNT_GRPQUOTA		0x200000 /* "old" group quota */
1009 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1010 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1011 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1012 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1013 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1014 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1015 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1016 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1017 
1018 /*
1019  * Mount flags set either automatically (could not be set by mount option)
1020  * based on per file system feature or property or in special cases such as
1021  * distinguishing between explicit mount option definition and default.
1022  */
1023 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1024 						      specified delalloc */
1025 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1026 						      size of blocksize * 8
1027 						      blocks */
1028 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1029 						      file systems */
1030 
1031 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1032 						~EXT4_MOUNT_##opt
1033 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1034 						EXT4_MOUNT_##opt
1035 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1036 					 EXT4_MOUNT_##opt)
1037 
1038 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1039 						~EXT4_MOUNT2_##opt
1040 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1041 						EXT4_MOUNT2_##opt
1042 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1043 					 EXT4_MOUNT2_##opt)
1044 
1045 #define ext4_test_and_set_bit		__test_and_set_bit_le
1046 #define ext4_set_bit			__set_bit_le
1047 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1048 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1049 #define ext4_clear_bit			__clear_bit_le
1050 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1051 #define ext4_test_bit			test_bit_le
1052 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1053 #define ext4_find_next_bit		find_next_bit_le
1054 
1055 extern void ext4_set_bits(void *bm, int cur, int len);
1056 
1057 /*
1058  * Maximal mount counts between two filesystem checks
1059  */
1060 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1061 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1062 
1063 /*
1064  * Behaviour when detecting errors
1065  */
1066 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1067 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1068 #define EXT4_ERRORS_PANIC		3	/* Panic */
1069 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1070 
1071 /* Metadata checksum algorithm codes */
1072 #define EXT4_CRC32C_CHKSUM		1
1073 
1074 /*
1075  * Structure of the super block
1076  */
1077 struct ext4_super_block {
1078 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1079 	__le32	s_blocks_count_lo;	/* Blocks count */
1080 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1081 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1082 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1083 	__le32	s_first_data_block;	/* First Data Block */
1084 	__le32	s_log_block_size;	/* Block size */
1085 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1086 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1087 	__le32	s_clusters_per_group;	/* # Clusters per group */
1088 	__le32	s_inodes_per_group;	/* # Inodes per group */
1089 	__le32	s_mtime;		/* Mount time */
1090 /*30*/	__le32	s_wtime;		/* Write time */
1091 	__le16	s_mnt_count;		/* Mount count */
1092 	__le16	s_max_mnt_count;	/* Maximal mount count */
1093 	__le16	s_magic;		/* Magic signature */
1094 	__le16	s_state;		/* File system state */
1095 	__le16	s_errors;		/* Behaviour when detecting errors */
1096 	__le16	s_minor_rev_level;	/* minor revision level */
1097 /*40*/	__le32	s_lastcheck;		/* time of last check */
1098 	__le32	s_checkinterval;	/* max. time between checks */
1099 	__le32	s_creator_os;		/* OS */
1100 	__le32	s_rev_level;		/* Revision level */
1101 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1102 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1103 	/*
1104 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1105 	 *
1106 	 * Note: the difference between the compatible feature set and
1107 	 * the incompatible feature set is that if there is a bit set
1108 	 * in the incompatible feature set that the kernel doesn't
1109 	 * know about, it should refuse to mount the filesystem.
1110 	 *
1111 	 * e2fsck's requirements are more strict; if it doesn't know
1112 	 * about a feature in either the compatible or incompatible
1113 	 * feature set, it must abort and not try to meddle with
1114 	 * things it doesn't understand...
1115 	 */
1116 	__le32	s_first_ino;		/* First non-reserved inode */
1117 	__le16  s_inode_size;		/* size of inode structure */
1118 	__le16	s_block_group_nr;	/* block group # of this superblock */
1119 	__le32	s_feature_compat;	/* compatible feature set */
1120 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1121 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1122 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1123 /*78*/	char	s_volume_name[16];	/* volume name */
1124 /*88*/	char	s_last_mounted[64];	/* directory where last mounted */
1125 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1126 	/*
1127 	 * Performance hints.  Directory preallocation should only
1128 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1129 	 */
1130 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1131 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1132 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1133 	/*
1134 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1135 	 */
1136 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1137 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1138 	__le32	s_journal_dev;		/* device number of journal file */
1139 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1140 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1141 	__u8	s_def_hash_version;	/* Default hash version to use */
1142 	__u8	s_jnl_backup_type;
1143 	__le16  s_desc_size;		/* size of group descriptor */
1144 /*100*/	__le32	s_default_mount_opts;
1145 	__le32	s_first_meta_bg;	/* First metablock block group */
1146 	__le32	s_mkfs_time;		/* When the filesystem was created */
1147 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1148 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1149 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1150 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1151 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1152 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1153 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1154 	__le32	s_flags;		/* Miscellaneous flags */
1155 	__le16  s_raid_stride;		/* RAID stride */
1156 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1157 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1158 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1159 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1160 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1161 	__u8	s_encryption_level;	/* versioning level for encryption */
1162 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1163 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1164 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1165 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1166 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1167 					      snapshot's future use */
1168 	__le32	s_snapshot_list;	/* inode number of the head of the
1169 					   on-disk snapshot list */
1170 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1171 	__le32	s_error_count;		/* number of fs errors */
1172 	__le32	s_first_error_time;	/* first time an error happened */
1173 	__le32	s_first_error_ino;	/* inode involved in first error */
1174 	__le64	s_first_error_block;	/* block involved of first error */
1175 	__u8	s_first_error_func[32];	/* function where the error happened */
1176 	__le32	s_first_error_line;	/* line number where error happened */
1177 	__le32	s_last_error_time;	/* most recent time of an error */
1178 	__le32	s_last_error_ino;	/* inode involved in last error */
1179 	__le32	s_last_error_line;	/* line number where error happened */
1180 	__le64	s_last_error_block;	/* block involved of last error */
1181 	__u8	s_last_error_func[32];	/* function where the error happened */
1182 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1183 	__u8	s_mount_opts[64];
1184 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1185 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1186 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1187 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1188 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1189 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1190 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1191 	__le32	s_reserved[100];	/* Padding to the end of the block */
1192 	__le32	s_checksum;		/* crc32c(superblock) */
1193 };
1194 
1195 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1196 
1197 #ifdef __KERNEL__
1198 
1199 /*
1200  * run-time mount flags
1201  */
1202 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1203 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1204 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1205 
1206 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1207 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1208 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1209 #else
1210 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1211 #endif
1212 
1213 /* Number of quota types we support */
1214 #define EXT4_MAXQUOTAS 2
1215 
1216 /*
1217  * fourth extended-fs super-block data in memory
1218  */
1219 struct ext4_sb_info {
1220 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1221 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1222 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1223 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1224 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1225 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1226 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1227 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1228 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1229 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1230 	unsigned long s_overhead;  /* # of fs overhead clusters */
1231 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1232 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1233 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1234 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1235 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1236 	struct buffer_head **s_group_desc;
1237 	unsigned int s_mount_opt;
1238 	unsigned int s_mount_opt2;
1239 	unsigned int s_mount_flags;
1240 	unsigned int s_def_mount_opt;
1241 	ext4_fsblk_t s_sb_block;
1242 	atomic64_t s_resv_clusters;
1243 	kuid_t s_resuid;
1244 	kgid_t s_resgid;
1245 	unsigned short s_mount_state;
1246 	unsigned short s_pad;
1247 	int s_addr_per_block_bits;
1248 	int s_desc_per_block_bits;
1249 	int s_inode_size;
1250 	int s_first_ino;
1251 	unsigned int s_inode_readahead_blks;
1252 	unsigned int s_inode_goal;
1253 	spinlock_t s_next_gen_lock;
1254 	u32 s_next_generation;
1255 	u32 s_hash_seed[4];
1256 	int s_def_hash_version;
1257 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1258 	struct percpu_counter s_freeclusters_counter;
1259 	struct percpu_counter s_freeinodes_counter;
1260 	struct percpu_counter s_dirs_counter;
1261 	struct percpu_counter s_dirtyclusters_counter;
1262 	struct blockgroup_lock *s_blockgroup_lock;
1263 	struct proc_dir_entry *s_proc;
1264 	struct kobject s_kobj;
1265 	struct completion s_kobj_unregister;
1266 	struct super_block *s_sb;
1267 
1268 	/* Journaling */
1269 	struct journal_s *s_journal;
1270 	struct list_head s_orphan;
1271 	struct mutex s_orphan_lock;
1272 	unsigned long s_resize_flags;		/* Flags indicating if there
1273 						   is a resizer */
1274 	unsigned long s_commit_interval;
1275 	u32 s_max_batch_time;
1276 	u32 s_min_batch_time;
1277 	struct block_device *journal_bdev;
1278 #ifdef CONFIG_QUOTA
1279 	char *s_qf_names[EXT4_MAXQUOTAS];	/* Names of quota files with journalled quota */
1280 	int s_jquota_fmt;			/* Format of quota to use */
1281 #endif
1282 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1283 	struct rb_root system_blks;
1284 
1285 #ifdef EXTENTS_STATS
1286 	/* ext4 extents stats */
1287 	unsigned long s_ext_min;
1288 	unsigned long s_ext_max;
1289 	unsigned long s_depth_max;
1290 	spinlock_t s_ext_stats_lock;
1291 	unsigned long s_ext_blocks;
1292 	unsigned long s_ext_extents;
1293 #endif
1294 
1295 	/* for buddy allocator */
1296 	struct ext4_group_info ***s_group_info;
1297 	struct inode *s_buddy_cache;
1298 	spinlock_t s_md_lock;
1299 	unsigned short *s_mb_offsets;
1300 	unsigned int *s_mb_maxs;
1301 	unsigned int s_group_info_size;
1302 
1303 	/* tunables */
1304 	unsigned long s_stripe;
1305 	unsigned int s_mb_stream_request;
1306 	unsigned int s_mb_max_to_scan;
1307 	unsigned int s_mb_min_to_scan;
1308 	unsigned int s_mb_stats;
1309 	unsigned int s_mb_order2_reqs;
1310 	unsigned int s_mb_group_prealloc;
1311 	unsigned int s_max_dir_size_kb;
1312 	/* where last allocation was done - for stream allocation */
1313 	unsigned long s_mb_last_group;
1314 	unsigned long s_mb_last_start;
1315 
1316 	/* stats for buddy allocator */
1317 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1318 	atomic_t s_bal_success;	/* we found long enough chunks */
1319 	atomic_t s_bal_allocated;	/* in blocks */
1320 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1321 	atomic_t s_bal_goals;	/* goal hits */
1322 	atomic_t s_bal_breaks;	/* too long searches */
1323 	atomic_t s_bal_2orders;	/* 2^order hits */
1324 	spinlock_t s_bal_lock;
1325 	unsigned long s_mb_buddies_generated;
1326 	unsigned long long s_mb_generation_time;
1327 	atomic_t s_mb_lost_chunks;
1328 	atomic_t s_mb_preallocated;
1329 	atomic_t s_mb_discarded;
1330 	atomic_t s_lock_busy;
1331 
1332 	/* locality groups */
1333 	struct ext4_locality_group __percpu *s_locality_groups;
1334 
1335 	/* for write statistics */
1336 	unsigned long s_sectors_written_start;
1337 	u64 s_kbytes_written;
1338 
1339 	/* the size of zero-out chunk */
1340 	unsigned int s_extent_max_zeroout_kb;
1341 
1342 	unsigned int s_log_groups_per_flex;
1343 	struct flex_groups *s_flex_groups;
1344 	ext4_group_t s_flex_groups_allocated;
1345 
1346 	/* workqueue for reserved extent conversions (buffered io) */
1347 	struct workqueue_struct *rsv_conversion_wq;
1348 
1349 	/* timer for periodic error stats printing */
1350 	struct timer_list s_err_report;
1351 
1352 	/* Lazy inode table initialization info */
1353 	struct ext4_li_request *s_li_request;
1354 	/* Wait multiplier for lazy initialization thread */
1355 	unsigned int s_li_wait_mult;
1356 
1357 	/* Kernel thread for multiple mount protection */
1358 	struct task_struct *s_mmp_tsk;
1359 
1360 	/* record the last minlen when FITRIM is called. */
1361 	atomic_t s_last_trim_minblks;
1362 
1363 	/* Reference to checksum algorithm driver via cryptoapi */
1364 	struct crypto_shash *s_chksum_driver;
1365 
1366 	/* Precomputed FS UUID checksum for seeding other checksums */
1367 	__u32 s_csum_seed;
1368 
1369 	/* Reclaim extents from extent status tree */
1370 	struct shrinker s_es_shrinker;
1371 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1372 	long s_es_nr_inode;
1373 	struct ext4_es_stats s_es_stats;
1374 	struct mb_cache *s_mb_cache;
1375 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1376 
1377 	/* Ratelimit ext4 messages. */
1378 	struct ratelimit_state s_err_ratelimit_state;
1379 	struct ratelimit_state s_warning_ratelimit_state;
1380 	struct ratelimit_state s_msg_ratelimit_state;
1381 };
1382 
1383 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1384 {
1385 	return sb->s_fs_info;
1386 }
1387 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1388 {
1389 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1390 }
1391 
1392 static inline struct timespec ext4_current_time(struct inode *inode)
1393 {
1394 	return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1395 		current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1396 }
1397 
1398 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1399 {
1400 	return ino == EXT4_ROOT_INO ||
1401 		ino == EXT4_USR_QUOTA_INO ||
1402 		ino == EXT4_GRP_QUOTA_INO ||
1403 		ino == EXT4_BOOT_LOADER_INO ||
1404 		ino == EXT4_JOURNAL_INO ||
1405 		ino == EXT4_RESIZE_INO ||
1406 		(ino >= EXT4_FIRST_INO(sb) &&
1407 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1408 }
1409 
1410 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1411 					      struct ext4_io_end *io_end)
1412 {
1413 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1414 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
1415 		atomic_inc(&EXT4_I(inode)->i_unwritten);
1416 	}
1417 }
1418 
1419 static inline ext4_io_end_t *ext4_inode_aio(struct inode *inode)
1420 {
1421 	return inode->i_private;
1422 }
1423 
1424 static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
1425 {
1426 	inode->i_private = io;
1427 }
1428 
1429 /*
1430  * Inode dynamic state flags
1431  */
1432 enum {
1433 	EXT4_STATE_JDATA,		/* journaled data exists */
1434 	EXT4_STATE_NEW,			/* inode is newly created */
1435 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1436 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1437 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1438 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1439 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1440 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1441 	EXT4_STATE_DIOREAD_LOCK,	/* Disable support for dio read
1442 					   nolocking */
1443 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1444 	EXT4_STATE_ORDERED_MODE,	/* data=ordered mode */
1445 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1446 };
1447 
1448 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1449 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1450 {									\
1451 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1452 }									\
1453 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1454 {									\
1455 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1456 }									\
1457 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1458 {									\
1459 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1460 }
1461 
1462 /* Add these declarations here only so that these functions can be
1463  * found by name.  Otherwise, they are very hard to locate. */
1464 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1465 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1466 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1467 EXT4_INODE_BIT_FNS(flag, flags, 0)
1468 
1469 /* Add these declarations here only so that these functions can be
1470  * found by name.  Otherwise, they are very hard to locate. */
1471 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1472 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1473 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1474 #if (BITS_PER_LONG < 64)
1475 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1476 
1477 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1478 {
1479 	(ei)->i_state_flags = 0;
1480 }
1481 #else
1482 EXT4_INODE_BIT_FNS(state, flags, 32)
1483 
1484 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1485 {
1486 	/* We depend on the fact that callers will set i_flags */
1487 }
1488 #endif
1489 #else
1490 /* Assume that user mode programs are passing in an ext4fs superblock, not
1491  * a kernel struct super_block.  This will allow us to call the feature-test
1492  * macros from user land. */
1493 #define EXT4_SB(sb)	(sb)
1494 #endif
1495 
1496 /*
1497  * Returns true if the inode is inode is encrypted
1498  */
1499 static inline int ext4_encrypted_inode(struct inode *inode)
1500 {
1501 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1502 	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
1503 #else
1504 	return 0;
1505 #endif
1506 }
1507 
1508 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1509 
1510 /*
1511  * Codes for operating systems
1512  */
1513 #define EXT4_OS_LINUX		0
1514 #define EXT4_OS_HURD		1
1515 #define EXT4_OS_MASIX		2
1516 #define EXT4_OS_FREEBSD		3
1517 #define EXT4_OS_LITES		4
1518 
1519 /*
1520  * Revision levels
1521  */
1522 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1523 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1524 
1525 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1526 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1527 
1528 #define EXT4_GOOD_OLD_INODE_SIZE 128
1529 
1530 /*
1531  * Feature set definitions
1532  */
1533 
1534 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)			\
1535 	((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1536 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)			\
1537 	((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1538 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)			\
1539 	((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1540 #define EXT4_SET_COMPAT_FEATURE(sb,mask)			\
1541 	EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1542 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)			\
1543 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1544 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)			\
1545 	EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1546 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)			\
1547 	EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1548 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
1549 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1550 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
1551 	EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1552 
1553 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1554 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1555 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1556 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1557 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1558 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1559 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1560 
1561 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1562 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1563 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1564 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1565 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1566 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1567 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1568 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1569 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1570 /*
1571  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1572  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1573  * all other data structures' checksums.  However, the METADATA_CSUM and
1574  * GDT_CSUM bits are mutually exclusive.
1575  */
1576 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1577 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1578 
1579 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1580 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1581 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1582 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1583 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1584 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1585 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1586 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1587 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1588 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1589 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1590 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM	0x2000 /* use crc32c for bg */
1591 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1592 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1593 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1594 
1595 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1596 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1597 					 EXT4_FEATURE_INCOMPAT_META_BG)
1598 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1599 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1600 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1601 
1602 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1603 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1604 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1605 					 EXT4_FEATURE_INCOMPAT_META_BG)
1606 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1607 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1608 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1609 
1610 #define EXT4_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR
1611 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1612 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1613 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1614 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1615 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1616 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1617 					 EXT4_FEATURE_INCOMPAT_MMP | \
1618 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1619 					 EXT4_FEATURE_INCOMPAT_ENCRYPT)
1620 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1621 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1622 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1623 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1624 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1625 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1626 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1627 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1628 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1629 					 EXT4_FEATURE_RO_COMPAT_QUOTA)
1630 
1631 /*
1632  * Default values for user and/or group using reserved blocks
1633  */
1634 #define	EXT4_DEF_RESUID		0
1635 #define	EXT4_DEF_RESGID		0
1636 
1637 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1638 
1639 /*
1640  * Default mount options
1641  */
1642 #define EXT4_DEFM_DEBUG		0x0001
1643 #define EXT4_DEFM_BSDGROUPS	0x0002
1644 #define EXT4_DEFM_XATTR_USER	0x0004
1645 #define EXT4_DEFM_ACL		0x0008
1646 #define EXT4_DEFM_UID16		0x0010
1647 #define EXT4_DEFM_JMODE		0x0060
1648 #define EXT4_DEFM_JMODE_DATA	0x0020
1649 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1650 #define EXT4_DEFM_JMODE_WBACK	0x0060
1651 #define EXT4_DEFM_NOBARRIER	0x0100
1652 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1653 #define EXT4_DEFM_DISCARD	0x0400
1654 #define EXT4_DEFM_NODELALLOC	0x0800
1655 
1656 /*
1657  * Default journal batch times
1658  */
1659 #define EXT4_DEF_MIN_BATCH_TIME	0
1660 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1661 
1662 /*
1663  * Minimum number of groups in a flexgroup before we separate out
1664  * directories into the first block group of a flexgroup
1665  */
1666 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1667 
1668 /*
1669  * Structure of a directory entry
1670  */
1671 #define EXT4_NAME_LEN 255
1672 
1673 struct ext4_dir_entry {
1674 	__le32	inode;			/* Inode number */
1675 	__le16	rec_len;		/* Directory entry length */
1676 	__le16	name_len;		/* Name length */
1677 	char	name[EXT4_NAME_LEN];	/* File name */
1678 };
1679 
1680 /*
1681  * The new version of the directory entry.  Since EXT4 structures are
1682  * stored in intel byte order, and the name_len field could never be
1683  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1684  * file_type field.
1685  */
1686 struct ext4_dir_entry_2 {
1687 	__le32	inode;			/* Inode number */
1688 	__le16	rec_len;		/* Directory entry length */
1689 	__u8	name_len;		/* Name length */
1690 	__u8	file_type;
1691 	char	name[EXT4_NAME_LEN];	/* File name */
1692 };
1693 
1694 /*
1695  * This is a bogus directory entry at the end of each leaf block that
1696  * records checksums.
1697  */
1698 struct ext4_dir_entry_tail {
1699 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1700 	__le16	det_rec_len;		/* 12 */
1701 	__u8	det_reserved_zero2;	/* Zero name length */
1702 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1703 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1704 };
1705 
1706 #define EXT4_DIRENT_TAIL(block, blocksize) \
1707 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1708 					((blocksize) - \
1709 					 sizeof(struct ext4_dir_entry_tail))))
1710 
1711 /*
1712  * Ext4 directory file types.  Only the low 3 bits are used.  The
1713  * other bits are reserved for now.
1714  */
1715 #define EXT4_FT_UNKNOWN		0
1716 #define EXT4_FT_REG_FILE	1
1717 #define EXT4_FT_DIR		2
1718 #define EXT4_FT_CHRDEV		3
1719 #define EXT4_FT_BLKDEV		4
1720 #define EXT4_FT_FIFO		5
1721 #define EXT4_FT_SOCK		6
1722 #define EXT4_FT_SYMLINK		7
1723 
1724 #define EXT4_FT_MAX		8
1725 
1726 #define EXT4_FT_DIR_CSUM	0xDE
1727 
1728 /*
1729  * EXT4_DIR_PAD defines the directory entries boundaries
1730  *
1731  * NOTE: It must be a multiple of 4
1732  */
1733 #define EXT4_DIR_PAD			4
1734 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1735 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1736 					 ~EXT4_DIR_ROUND)
1737 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1738 
1739 /*
1740  * If we ever get support for fs block sizes > page_size, we'll need
1741  * to remove the #if statements in the next two functions...
1742  */
1743 static inline unsigned int
1744 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1745 {
1746 	unsigned len = le16_to_cpu(dlen);
1747 
1748 #if (PAGE_CACHE_SIZE >= 65536)
1749 	if (len == EXT4_MAX_REC_LEN || len == 0)
1750 		return blocksize;
1751 	return (len & 65532) | ((len & 3) << 16);
1752 #else
1753 	return len;
1754 #endif
1755 }
1756 
1757 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1758 {
1759 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1760 		BUG();
1761 #if (PAGE_CACHE_SIZE >= 65536)
1762 	if (len < 65536)
1763 		return cpu_to_le16(len);
1764 	if (len == blocksize) {
1765 		if (blocksize == 65536)
1766 			return cpu_to_le16(EXT4_MAX_REC_LEN);
1767 		else
1768 			return cpu_to_le16(0);
1769 	}
1770 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1771 #else
1772 	return cpu_to_le16(len);
1773 #endif
1774 }
1775 
1776 /*
1777  * Hash Tree Directory indexing
1778  * (c) Daniel Phillips, 2001
1779  */
1780 
1781 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1782 				      EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1783 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1784 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1785 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1786 
1787 /* Legal values for the dx_root hash_version field: */
1788 
1789 #define DX_HASH_LEGACY		0
1790 #define DX_HASH_HALF_MD4	1
1791 #define DX_HASH_TEA		2
1792 #define DX_HASH_LEGACY_UNSIGNED	3
1793 #define DX_HASH_HALF_MD4_UNSIGNED	4
1794 #define DX_HASH_TEA_UNSIGNED		5
1795 
1796 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1797 			      const void *address, unsigned int length)
1798 {
1799 	struct {
1800 		struct shash_desc shash;
1801 		char ctx[4];
1802 	} desc;
1803 	int err;
1804 
1805 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
1806 
1807 	desc.shash.tfm = sbi->s_chksum_driver;
1808 	desc.shash.flags = 0;
1809 	*(u32 *)desc.ctx = crc;
1810 
1811 	err = crypto_shash_update(&desc.shash, address, length);
1812 	BUG_ON(err);
1813 
1814 	return *(u32 *)desc.ctx;
1815 }
1816 
1817 #ifdef __KERNEL__
1818 
1819 /* hash info structure used by the directory hash */
1820 struct dx_hash_info
1821 {
1822 	u32		hash;
1823 	u32		minor_hash;
1824 	int		hash_version;
1825 	u32		*seed;
1826 };
1827 
1828 
1829 /* 32 and 64 bit signed EOF for dx directories */
1830 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1831 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1832 
1833 
1834 /*
1835  * Control parameters used by ext4_htree_next_block
1836  */
1837 #define HASH_NB_ALWAYS		1
1838 
1839 struct ext4_filename {
1840 	const struct qstr *usr_fname;
1841 	struct ext4_str disk_name;
1842 	struct dx_hash_info hinfo;
1843 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1844 	struct ext4_str crypto_buf;
1845 #endif
1846 };
1847 
1848 #define fname_name(p) ((p)->disk_name.name)
1849 #define fname_len(p)  ((p)->disk_name.len)
1850 
1851 /*
1852  * Describe an inode's exact location on disk and in memory
1853  */
1854 struct ext4_iloc
1855 {
1856 	struct buffer_head *bh;
1857 	unsigned long offset;
1858 	ext4_group_t block_group;
1859 };
1860 
1861 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1862 {
1863 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1864 }
1865 
1866 /*
1867  * This structure is stuffed into the struct file's private_data field
1868  * for directories.  It is where we put information so that we can do
1869  * readdir operations in hash tree order.
1870  */
1871 struct dir_private_info {
1872 	struct rb_root	root;
1873 	struct rb_node	*curr_node;
1874 	struct fname	*extra_fname;
1875 	loff_t		last_pos;
1876 	__u32		curr_hash;
1877 	__u32		curr_minor_hash;
1878 	__u32		next_hash;
1879 };
1880 
1881 /* calculate the first block number of the group */
1882 static inline ext4_fsblk_t
1883 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1884 {
1885 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1886 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1887 }
1888 
1889 /*
1890  * Special error return code only used by dx_probe() and its callers.
1891  */
1892 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
1893 
1894 /*
1895  * Timeout and state flag for lazy initialization inode thread.
1896  */
1897 #define EXT4_DEF_LI_WAIT_MULT			10
1898 #define EXT4_DEF_LI_MAX_START_DELAY		5
1899 #define EXT4_LAZYINIT_QUIT			0x0001
1900 #define EXT4_LAZYINIT_RUNNING			0x0002
1901 
1902 /*
1903  * Lazy inode table initialization info
1904  */
1905 struct ext4_lazy_init {
1906 	unsigned long		li_state;
1907 	struct list_head	li_request_list;
1908 	struct mutex		li_list_mtx;
1909 };
1910 
1911 struct ext4_li_request {
1912 	struct super_block	*lr_super;
1913 	struct ext4_sb_info	*lr_sbi;
1914 	ext4_group_t		lr_next_group;
1915 	struct list_head	lr_request;
1916 	unsigned long		lr_next_sched;
1917 	unsigned long		lr_timeout;
1918 };
1919 
1920 struct ext4_features {
1921 	struct kobject f_kobj;
1922 	struct completion f_kobj_unregister;
1923 };
1924 
1925 /*
1926  * This structure will be used for multiple mount protection. It will be
1927  * written into the block number saved in the s_mmp_block field in the
1928  * superblock. Programs that check MMP should assume that if
1929  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1930  * to use the filesystem, regardless of how old the timestamp is.
1931  */
1932 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1933 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1934 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1935 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1936 
1937 struct mmp_struct {
1938 	__le32	mmp_magic;		/* Magic number for MMP */
1939 	__le32	mmp_seq;		/* Sequence no. updated periodically */
1940 
1941 	/*
1942 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1943 	 * purposes and do not affect the correctness of the algorithm
1944 	 */
1945 	__le64	mmp_time;		/* Time last updated */
1946 	char	mmp_nodename[64];	/* Node which last updated MMP block */
1947 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
1948 
1949 	/*
1950 	 * mmp_check_interval is used to verify if the MMP block has been
1951 	 * updated on the block device. The value is updated based on the
1952 	 * maximum time to write the MMP block during an update cycle.
1953 	 */
1954 	__le16	mmp_check_interval;
1955 
1956 	__le16	mmp_pad1;
1957 	__le32	mmp_pad2[226];
1958 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
1959 };
1960 
1961 /* arguments passed to the mmp thread */
1962 struct mmpd_data {
1963 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
1964 	struct super_block *sb;  /* super block of the fs */
1965 };
1966 
1967 /*
1968  * Check interval multiplier
1969  * The MMP block is written every update interval and initially checked every
1970  * update interval x the multiplier (the value is then adapted based on the
1971  * write latency). The reason is that writes can be delayed under load and we
1972  * don't want readers to incorrectly assume that the filesystem is no longer
1973  * in use.
1974  */
1975 #define EXT4_MMP_CHECK_MULT		2UL
1976 
1977 /*
1978  * Minimum interval for MMP checking in seconds.
1979  */
1980 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
1981 
1982 /*
1983  * Maximum interval for MMP checking in seconds.
1984  */
1985 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
1986 
1987 /*
1988  * Function prototypes
1989  */
1990 
1991 /*
1992  * Ok, these declarations are also in <linux/kernel.h> but none of the
1993  * ext4 source programs needs to include it so they are duplicated here.
1994  */
1995 # define NORET_TYPE	/**/
1996 # define ATTRIB_NORET	__attribute__((noreturn))
1997 # define NORET_AND	noreturn,
1998 
1999 /* bitmap.c */
2000 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2001 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2002 				struct ext4_group_desc *gdp,
2003 				struct buffer_head *bh, int sz);
2004 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2005 				  struct ext4_group_desc *gdp,
2006 				  struct buffer_head *bh, int sz);
2007 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2008 				struct ext4_group_desc *gdp,
2009 				struct buffer_head *bh);
2010 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2011 				  struct ext4_group_desc *gdp,
2012 				  struct buffer_head *bh);
2013 
2014 /* balloc.c */
2015 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2016 					 ext4_fsblk_t blocknr,
2017 					 ext4_group_t *blockgrpp,
2018 					 ext4_grpblk_t *offsetp);
2019 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2020 					  ext4_fsblk_t block);
2021 
2022 extern unsigned int ext4_block_group(struct super_block *sb,
2023 			ext4_fsblk_t blocknr);
2024 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2025 			ext4_fsblk_t blocknr);
2026 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2027 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2028 			ext4_group_t group);
2029 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2030 					 ext4_fsblk_t goal,
2031 					 unsigned int flags,
2032 					 unsigned long *count,
2033 					 int *errp);
2034 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2035 				    s64 nclusters, unsigned int flags);
2036 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2037 extern void ext4_check_blocks_bitmap(struct super_block *);
2038 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2039 						    ext4_group_t block_group,
2040 						    struct buffer_head ** bh);
2041 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2042 
2043 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2044 						ext4_group_t block_group);
2045 extern int ext4_wait_block_bitmap(struct super_block *sb,
2046 				  ext4_group_t block_group,
2047 				  struct buffer_head *bh);
2048 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2049 						  ext4_group_t block_group);
2050 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2051 					      ext4_group_t block_group,
2052 					      struct ext4_group_desc *gdp);
2053 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2054 
2055 /* crypto_policy.c */
2056 int ext4_is_child_context_consistent_with_parent(struct inode *parent,
2057 						 struct inode *child);
2058 int ext4_inherit_context(struct inode *parent, struct inode *child);
2059 void ext4_to_hex(char *dst, char *src, size_t src_size);
2060 int ext4_process_policy(const struct ext4_encryption_policy *policy,
2061 			struct inode *inode);
2062 int ext4_get_policy(struct inode *inode,
2063 		    struct ext4_encryption_policy *policy);
2064 
2065 /* crypto.c */
2066 extern struct kmem_cache *ext4_crypt_info_cachep;
2067 bool ext4_valid_contents_enc_mode(uint32_t mode);
2068 uint32_t ext4_validate_encryption_key_size(uint32_t mode, uint32_t size);
2069 extern struct workqueue_struct *ext4_read_workqueue;
2070 struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode);
2071 void ext4_release_crypto_ctx(struct ext4_crypto_ctx *ctx);
2072 void ext4_restore_control_page(struct page *data_page);
2073 struct page *ext4_encrypt(struct inode *inode,
2074 			  struct page *plaintext_page);
2075 int ext4_decrypt(struct ext4_crypto_ctx *ctx, struct page *page);
2076 int ext4_decrypt_one(struct inode *inode, struct page *page);
2077 int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex);
2078 
2079 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2080 int ext4_init_crypto(void);
2081 void ext4_exit_crypto(void);
2082 static inline int ext4_sb_has_crypto(struct super_block *sb)
2083 {
2084 	return EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT);
2085 }
2086 #else
2087 static inline int ext4_init_crypto(void) { return 0; }
2088 static inline void ext4_exit_crypto(void) { }
2089 static inline int ext4_sb_has_crypto(struct super_block *sb)
2090 {
2091 	return 0;
2092 }
2093 #endif
2094 
2095 /* crypto_fname.c */
2096 bool ext4_valid_filenames_enc_mode(uint32_t mode);
2097 u32 ext4_fname_crypto_round_up(u32 size, u32 blksize);
2098 unsigned ext4_fname_encrypted_size(struct inode *inode, u32 ilen);
2099 int ext4_fname_crypto_alloc_buffer(struct inode *inode,
2100 				   u32 ilen, struct ext4_str *crypto_str);
2101 int _ext4_fname_disk_to_usr(struct inode *inode,
2102 			    struct dx_hash_info *hinfo,
2103 			    const struct ext4_str *iname,
2104 			    struct ext4_str *oname);
2105 int ext4_fname_disk_to_usr(struct inode *inode,
2106 			   struct dx_hash_info *hinfo,
2107 			   const struct ext4_dir_entry_2 *de,
2108 			   struct ext4_str *oname);
2109 int ext4_fname_usr_to_disk(struct inode *inode,
2110 			   const struct qstr *iname,
2111 			   struct ext4_str *oname);
2112 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2113 void ext4_fname_crypto_free_buffer(struct ext4_str *crypto_str);
2114 int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
2115 			      int lookup, struct ext4_filename *fname);
2116 void ext4_fname_free_filename(struct ext4_filename *fname);
2117 #else
2118 static inline
2119 int ext4_setup_fname_crypto(struct inode *inode)
2120 {
2121 	return 0;
2122 }
2123 static inline void ext4_fname_crypto_free_buffer(struct ext4_str *p) { }
2124 static inline int ext4_fname_setup_filename(struct inode *dir,
2125 				     const struct qstr *iname,
2126 				     int lookup, struct ext4_filename *fname)
2127 {
2128 	fname->usr_fname = iname;
2129 	fname->disk_name.name = (unsigned char *) iname->name;
2130 	fname->disk_name.len = iname->len;
2131 	return 0;
2132 }
2133 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2134 #endif
2135 
2136 
2137 /* crypto_key.c */
2138 void ext4_free_crypt_info(struct ext4_crypt_info *ci);
2139 void ext4_free_encryption_info(struct inode *inode, struct ext4_crypt_info *ci);
2140 int _ext4_get_encryption_info(struct inode *inode);
2141 
2142 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2143 int ext4_has_encryption_key(struct inode *inode);
2144 
2145 static inline int ext4_get_encryption_info(struct inode *inode)
2146 {
2147 	struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
2148 
2149 	if (!ci ||
2150 	    (ci->ci_keyring_key &&
2151 	     (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
2152 					   (1 << KEY_FLAG_REVOKED) |
2153 					   (1 << KEY_FLAG_DEAD)))))
2154 		return _ext4_get_encryption_info(inode);
2155 	return 0;
2156 }
2157 
2158 static inline struct ext4_crypt_info *ext4_encryption_info(struct inode *inode)
2159 {
2160 	return EXT4_I(inode)->i_crypt_info;
2161 }
2162 
2163 #else
2164 static inline int ext4_has_encryption_key(struct inode *inode)
2165 {
2166 	return 0;
2167 }
2168 static inline int ext4_get_encryption_info(struct inode *inode)
2169 {
2170 	return 0;
2171 }
2172 static inline struct ext4_crypt_info *ext4_encryption_info(struct inode *inode)
2173 {
2174 	return NULL;
2175 }
2176 #endif
2177 
2178 
2179 /* dir.c */
2180 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2181 				  struct file *,
2182 				  struct ext4_dir_entry_2 *,
2183 				  struct buffer_head *, char *, int,
2184 				  unsigned int);
2185 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2186 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2187 					(de), (bh), (buf), (size), (offset)))
2188 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2189 				__u32 minor_hash,
2190 				struct ext4_dir_entry_2 *dirent,
2191 				struct ext4_str *ent_name);
2192 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2193 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2194 			     struct buffer_head *bh,
2195 			     void *buf, int buf_size,
2196 			     struct ext4_filename *fname,
2197 			     struct ext4_dir_entry_2 **dest_de);
2198 int ext4_insert_dentry(struct inode *dir,
2199 		       struct inode *inode,
2200 		       struct ext4_dir_entry_2 *de,
2201 		       int buf_size,
2202 		       struct ext4_filename *fname);
2203 static inline void ext4_update_dx_flag(struct inode *inode)
2204 {
2205 	if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
2206 				     EXT4_FEATURE_COMPAT_DIR_INDEX))
2207 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2208 }
2209 static unsigned char ext4_filetype_table[] = {
2210 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2211 };
2212 
2213 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2214 {
2215 	if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) ||
2216 	    (filetype >= EXT4_FT_MAX))
2217 		return DT_UNKNOWN;
2218 
2219 	return ext4_filetype_table[filetype];
2220 }
2221 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2222 			     void *buf, int buf_size);
2223 
2224 /* fsync.c */
2225 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2226 
2227 /* hash.c */
2228 extern int ext4fs_dirhash(const char *name, int len, struct
2229 			  dx_hash_info *hinfo);
2230 
2231 /* ialloc.c */
2232 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2233 				      const struct qstr *qstr, __u32 goal,
2234 				      uid_t *owner, int handle_type,
2235 				      unsigned int line_no, int nblocks);
2236 
2237 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner) \
2238 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2239 			 0, 0, 0)
2240 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2241 				    type, nblocks)		    \
2242 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2243 			 (type), __LINE__, (nblocks))
2244 
2245 
2246 extern void ext4_free_inode(handle_t *, struct inode *);
2247 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2248 extern unsigned long ext4_count_free_inodes(struct super_block *);
2249 extern unsigned long ext4_count_dirs(struct super_block *);
2250 extern void ext4_check_inodes_bitmap(struct super_block *);
2251 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2252 extern int ext4_init_inode_table(struct super_block *sb,
2253 				 ext4_group_t group, int barrier);
2254 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2255 
2256 /* mballoc.c */
2257 extern long ext4_mb_stats;
2258 extern long ext4_mb_max_to_scan;
2259 extern int ext4_mb_init(struct super_block *);
2260 extern int ext4_mb_release(struct super_block *);
2261 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2262 				struct ext4_allocation_request *, int *);
2263 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2264 extern void ext4_discard_preallocations(struct inode *);
2265 extern int __init ext4_init_mballoc(void);
2266 extern void ext4_exit_mballoc(void);
2267 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2268 			     struct buffer_head *bh, ext4_fsblk_t block,
2269 			     unsigned long count, int flags);
2270 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2271 				   ext4_group_t ngroups);
2272 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2273 		ext4_group_t i, struct ext4_group_desc *desc);
2274 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2275 				ext4_fsblk_t block, unsigned long count);
2276 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2277 
2278 /* inode.c */
2279 int ext4_inode_is_fast_symlink(struct inode *inode);
2280 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2281 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2282 int ext4_get_block_write(struct inode *inode, sector_t iblock,
2283 			 struct buffer_head *bh_result, int create);
2284 int ext4_get_block(struct inode *inode, sector_t iblock,
2285 				struct buffer_head *bh_result, int create);
2286 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2287 			   struct buffer_head *bh, int create);
2288 int ext4_walk_page_buffers(handle_t *handle,
2289 			   struct buffer_head *head,
2290 			   unsigned from,
2291 			   unsigned to,
2292 			   int *partial,
2293 			   int (*fn)(handle_t *handle,
2294 				     struct buffer_head *bh));
2295 int do_journal_get_write_access(handle_t *handle,
2296 				struct buffer_head *bh);
2297 #define FALL_BACK_TO_NONDELALLOC 1
2298 #define CONVERT_INLINE_DATA	 2
2299 
2300 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2301 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
2302 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2303 extern int  ext4_setattr(struct dentry *, struct iattr *);
2304 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2305 				struct kstat *stat);
2306 extern void ext4_evict_inode(struct inode *);
2307 extern void ext4_clear_inode(struct inode *);
2308 extern int  ext4_sync_inode(handle_t *, struct inode *);
2309 extern void ext4_dirty_inode(struct inode *, int);
2310 extern int ext4_change_inode_journal_flag(struct inode *, int);
2311 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2312 extern int ext4_inode_attach_jinode(struct inode *inode);
2313 extern int ext4_can_truncate(struct inode *inode);
2314 extern void ext4_truncate(struct inode *);
2315 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2316 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2317 extern void ext4_set_inode_flags(struct inode *);
2318 extern void ext4_get_inode_flags(struct ext4_inode_info *);
2319 extern int ext4_alloc_da_blocks(struct inode *inode);
2320 extern void ext4_set_aops(struct inode *inode);
2321 extern int ext4_writepage_trans_blocks(struct inode *);
2322 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2323 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2324 			     loff_t lstart, loff_t lend);
2325 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2326 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2327 extern void ext4_da_update_reserve_space(struct inode *inode,
2328 					int used, int quota_claim);
2329 
2330 /* indirect.c */
2331 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2332 				struct ext4_map_blocks *map, int flags);
2333 extern ssize_t ext4_ind_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
2334 				  loff_t offset);
2335 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2336 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2337 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2338 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2339 				 ext4_lblk_t start, ext4_lblk_t end);
2340 
2341 /* ioctl.c */
2342 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2343 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2344 
2345 /* migrate.c */
2346 extern int ext4_ext_migrate(struct inode *);
2347 extern int ext4_ind_migrate(struct inode *inode);
2348 
2349 /* namei.c */
2350 extern int ext4_dirent_csum_verify(struct inode *inode,
2351 				   struct ext4_dir_entry *dirent);
2352 extern int ext4_orphan_add(handle_t *, struct inode *);
2353 extern int ext4_orphan_del(handle_t *, struct inode *);
2354 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2355 				__u32 start_minor_hash, __u32 *next_hash);
2356 extern int ext4_search_dir(struct buffer_head *bh,
2357 			   char *search_buf,
2358 			   int buf_size,
2359 			   struct inode *dir,
2360 			   struct ext4_filename *fname,
2361 			   const struct qstr *d_name,
2362 			   unsigned int offset,
2363 			   struct ext4_dir_entry_2 **res_dir);
2364 extern int ext4_generic_delete_entry(handle_t *handle,
2365 				     struct inode *dir,
2366 				     struct ext4_dir_entry_2 *de_del,
2367 				     struct buffer_head *bh,
2368 				     void *entry_buf,
2369 				     int buf_size,
2370 				     int csum_size);
2371 extern int ext4_empty_dir(struct inode *inode);
2372 
2373 /* resize.c */
2374 extern int ext4_group_add(struct super_block *sb,
2375 				struct ext4_new_group_data *input);
2376 extern int ext4_group_extend(struct super_block *sb,
2377 				struct ext4_super_block *es,
2378 				ext4_fsblk_t n_blocks_count);
2379 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2380 
2381 /* super.c */
2382 extern int ext4_calculate_overhead(struct super_block *sb);
2383 extern void ext4_superblock_csum_set(struct super_block *sb);
2384 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2385 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2386 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2387 				    ext4_group_t ngroup);
2388 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2389 				     char nbuf[16]);
2390 
2391 extern __printf(4, 5)
2392 void __ext4_error(struct super_block *, const char *, unsigned int,
2393 		  const char *, ...);
2394 extern __printf(5, 6)
2395 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2396 		      const char *, ...);
2397 extern __printf(5, 6)
2398 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2399 		     const char *, ...);
2400 extern void __ext4_std_error(struct super_block *, const char *,
2401 			     unsigned int, int);
2402 extern __printf(4, 5)
2403 void __ext4_abort(struct super_block *, const char *, unsigned int,
2404 		  const char *, ...);
2405 extern __printf(4, 5)
2406 void __ext4_warning(struct super_block *, const char *, unsigned int,
2407 		    const char *, ...);
2408 extern __printf(3, 4)
2409 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2410 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2411 			   const char *, unsigned int, const char *);
2412 extern __printf(7, 8)
2413 void __ext4_grp_locked_error(const char *, unsigned int,
2414 			     struct super_block *, ext4_group_t,
2415 			     unsigned long, ext4_fsblk_t,
2416 			     const char *, ...);
2417 
2418 #ifdef CONFIG_PRINTK
2419 
2420 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2421 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2422 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2423 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2424 #define ext4_error(sb, fmt, ...)					\
2425 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2426 #define ext4_abort(sb, fmt, ...)					\
2427 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2428 #define ext4_warning(sb, fmt, ...)					\
2429 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2430 #define ext4_msg(sb, level, fmt, ...)				\
2431 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2432 #define dump_mmp_msg(sb, mmp, msg)					\
2433 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2434 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2435 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2436 				fmt, ##__VA_ARGS__)
2437 
2438 #else
2439 
2440 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2441 do {									\
2442 	no_printk(fmt, ##__VA_ARGS__);					\
2443 	__ext4_error_inode(inode, "", 0, block, " ");			\
2444 } while (0)
2445 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2446 do {									\
2447 	no_printk(fmt, ##__VA_ARGS__);					\
2448 	__ext4_error_file(file, "", 0, block, " ");			\
2449 } while (0)
2450 #define ext4_error(sb, fmt, ...)					\
2451 do {									\
2452 	no_printk(fmt, ##__VA_ARGS__);					\
2453 	__ext4_error(sb, "", 0, " ");					\
2454 } while (0)
2455 #define ext4_abort(sb, fmt, ...)					\
2456 do {									\
2457 	no_printk(fmt, ##__VA_ARGS__);					\
2458 	__ext4_abort(sb, "", 0, " ");					\
2459 } while (0)
2460 #define ext4_warning(sb, fmt, ...)					\
2461 do {									\
2462 	no_printk(fmt, ##__VA_ARGS__);					\
2463 	__ext4_warning(sb, "", 0, " ");					\
2464 } while (0)
2465 #define ext4_msg(sb, level, fmt, ...)					\
2466 do {									\
2467 	no_printk(fmt, ##__VA_ARGS__);					\
2468 	__ext4_msg(sb, "", " ");					\
2469 } while (0)
2470 #define dump_mmp_msg(sb, mmp, msg)					\
2471 	__dump_mmp_msg(sb, mmp, "", 0, "")
2472 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2473 do {									\
2474 	no_printk(fmt, ##__VA_ARGS__);				\
2475 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2476 } while (0)
2477 
2478 #endif
2479 
2480 extern void ext4_update_dynamic_rev(struct super_block *sb);
2481 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2482 					__u32 compat);
2483 extern int ext4_update_rocompat_feature(handle_t *handle,
2484 					struct super_block *sb,	__u32 rocompat);
2485 extern int ext4_update_incompat_feature(handle_t *handle,
2486 					struct super_block *sb,	__u32 incompat);
2487 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2488 				      struct ext4_group_desc *bg);
2489 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2490 				      struct ext4_group_desc *bg);
2491 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2492 				     struct ext4_group_desc *bg);
2493 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2494 				      struct ext4_group_desc *bg);
2495 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2496 				 struct ext4_group_desc *bg);
2497 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2498 				struct ext4_group_desc *bg);
2499 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2500 				   struct ext4_group_desc *bg);
2501 extern void ext4_block_bitmap_set(struct super_block *sb,
2502 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2503 extern void ext4_inode_bitmap_set(struct super_block *sb,
2504 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2505 extern void ext4_inode_table_set(struct super_block *sb,
2506 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2507 extern void ext4_free_group_clusters_set(struct super_block *sb,
2508 					 struct ext4_group_desc *bg,
2509 					 __u32 count);
2510 extern void ext4_free_inodes_set(struct super_block *sb,
2511 				struct ext4_group_desc *bg, __u32 count);
2512 extern void ext4_used_dirs_set(struct super_block *sb,
2513 				struct ext4_group_desc *bg, __u32 count);
2514 extern void ext4_itable_unused_set(struct super_block *sb,
2515 				   struct ext4_group_desc *bg, __u32 count);
2516 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2517 				       struct ext4_group_desc *gdp);
2518 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2519 				     struct ext4_group_desc *gdp);
2520 extern int ext4_register_li_request(struct super_block *sb,
2521 				    ext4_group_t first_not_zeroed);
2522 
2523 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2524 {
2525 	return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2526 					  EXT4_FEATURE_RO_COMPAT_GDT_CSUM) ||
2527 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
2528 }
2529 
2530 static inline int ext4_has_metadata_csum(struct super_block *sb)
2531 {
2532 	WARN_ON_ONCE(EXT4_HAS_RO_COMPAT_FEATURE(sb,
2533 			EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
2534 		     !EXT4_SB(sb)->s_chksum_driver);
2535 
2536 	return (EXT4_SB(sb)->s_chksum_driver != NULL);
2537 }
2538 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2539 {
2540 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2541 		le32_to_cpu(es->s_blocks_count_lo);
2542 }
2543 
2544 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2545 {
2546 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2547 		le32_to_cpu(es->s_r_blocks_count_lo);
2548 }
2549 
2550 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2551 {
2552 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2553 		le32_to_cpu(es->s_free_blocks_count_lo);
2554 }
2555 
2556 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2557 					 ext4_fsblk_t blk)
2558 {
2559 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2560 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2561 }
2562 
2563 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2564 					      ext4_fsblk_t blk)
2565 {
2566 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2567 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2568 }
2569 
2570 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2571 					   ext4_fsblk_t blk)
2572 {
2573 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2574 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2575 }
2576 
2577 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2578 {
2579 	if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2580 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2581 			le32_to_cpu(raw_inode->i_size_lo);
2582 	else
2583 		return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2584 }
2585 
2586 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2587 {
2588 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2589 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2590 }
2591 
2592 static inline
2593 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2594 					    ext4_group_t group)
2595 {
2596 	 struct ext4_group_info ***grp_info;
2597 	 long indexv, indexh;
2598 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2599 	 grp_info = EXT4_SB(sb)->s_group_info;
2600 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2601 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2602 	 return grp_info[indexv][indexh];
2603 }
2604 
2605 /*
2606  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2607  * the locking protocol documented in the comments of ext4_group_add()
2608  * in resize.c
2609  */
2610 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2611 {
2612 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2613 
2614 	smp_rmb();
2615 	return ngroups;
2616 }
2617 
2618 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2619 					     ext4_group_t block_group)
2620 {
2621 	return block_group >> sbi->s_log_groups_per_flex;
2622 }
2623 
2624 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2625 {
2626 	return 1 << sbi->s_log_groups_per_flex;
2627 }
2628 
2629 #define ext4_std_error(sb, errno)				\
2630 do {								\
2631 	if ((errno))						\
2632 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2633 } while (0)
2634 
2635 #ifdef CONFIG_SMP
2636 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2637  * counters. So we need to make sure we have free clusters more
2638  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2639  */
2640 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2641 #else
2642 #define EXT4_FREECLUSTERS_WATERMARK 0
2643 #endif
2644 
2645 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2646 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2647 {
2648 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2649 		     !mutex_is_locked(&inode->i_mutex));
2650 	down_write(&EXT4_I(inode)->i_data_sem);
2651 	if (newsize > EXT4_I(inode)->i_disksize)
2652 		EXT4_I(inode)->i_disksize = newsize;
2653 	up_write(&EXT4_I(inode)->i_data_sem);
2654 }
2655 
2656 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2657 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2658 {
2659 	int changed = 0;
2660 
2661 	if (newsize > inode->i_size) {
2662 		i_size_write(inode, newsize);
2663 		changed = 1;
2664 	}
2665 	if (newsize > EXT4_I(inode)->i_disksize) {
2666 		ext4_update_i_disksize(inode, newsize);
2667 		changed |= 2;
2668 	}
2669 	return changed;
2670 }
2671 
2672 struct ext4_group_info {
2673 	unsigned long   bb_state;
2674 	struct rb_root  bb_free_root;
2675 	ext4_grpblk_t	bb_first_free;	/* first free block */
2676 	ext4_grpblk_t	bb_free;	/* total free blocks */
2677 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2678 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2679 	struct          list_head bb_prealloc_list;
2680 #ifdef DOUBLE_CHECK
2681 	void            *bb_bitmap;
2682 #endif
2683 	struct rw_semaphore alloc_sem;
2684 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2685 					 * regions, index is order.
2686 					 * bb_counters[3] = 5 means
2687 					 * 5 free 8-block regions. */
2688 };
2689 
2690 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2691 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2692 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2693 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2694 
2695 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2696 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2697 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2698 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2699 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2700 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2701 
2702 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2703 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2704 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2705 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2706 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2707 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2708 
2709 #define EXT4_MAX_CONTENTION		8
2710 #define EXT4_CONTENTION_THRESHOLD	2
2711 
2712 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2713 					      ext4_group_t group)
2714 {
2715 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2716 }
2717 
2718 /*
2719  * Returns true if the filesystem is busy enough that attempts to
2720  * access the block group locks has run into contention.
2721  */
2722 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2723 {
2724 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2725 }
2726 
2727 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2728 {
2729 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2730 	if (spin_trylock(lock))
2731 		/*
2732 		 * We're able to grab the lock right away, so drop the
2733 		 * lock contention counter.
2734 		 */
2735 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2736 	else {
2737 		/*
2738 		 * The lock is busy, so bump the contention counter,
2739 		 * and then wait on the spin lock.
2740 		 */
2741 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2742 				  EXT4_MAX_CONTENTION);
2743 		spin_lock(lock);
2744 	}
2745 }
2746 
2747 static inline void ext4_unlock_group(struct super_block *sb,
2748 					ext4_group_t group)
2749 {
2750 	spin_unlock(ext4_group_lock_ptr(sb, group));
2751 }
2752 
2753 /*
2754  * Block validity checking
2755  */
2756 #define ext4_check_indirect_blockref(inode, bh)				\
2757 	ext4_check_blockref(__func__, __LINE__, inode,			\
2758 			    (__le32 *)(bh)->b_data,			\
2759 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2760 
2761 #define ext4_ind_check_inode(inode)					\
2762 	ext4_check_blockref(__func__, __LINE__, inode,			\
2763 			    EXT4_I(inode)->i_data,			\
2764 			    EXT4_NDIR_BLOCKS)
2765 
2766 /*
2767  * Inodes and files operations
2768  */
2769 
2770 /* dir.c */
2771 extern const struct file_operations ext4_dir_operations;
2772 
2773 /* file.c */
2774 extern const struct inode_operations ext4_file_inode_operations;
2775 extern const struct file_operations ext4_file_operations;
2776 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2777 
2778 /* inline.c */
2779 extern int ext4_get_max_inline_size(struct inode *inode);
2780 extern int ext4_find_inline_data_nolock(struct inode *inode);
2781 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2782 				 unsigned int len);
2783 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2784 
2785 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2786 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2787 					 struct inode *inode,
2788 					 loff_t pos, unsigned len,
2789 					 unsigned flags,
2790 					 struct page **pagep);
2791 extern int ext4_write_inline_data_end(struct inode *inode,
2792 				      loff_t pos, unsigned len,
2793 				      unsigned copied,
2794 				      struct page *page);
2795 extern struct buffer_head *
2796 ext4_journalled_write_inline_data(struct inode *inode,
2797 				  unsigned len,
2798 				  struct page *page);
2799 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
2800 					   struct inode *inode,
2801 					   loff_t pos, unsigned len,
2802 					   unsigned flags,
2803 					   struct page **pagep,
2804 					   void **fsdata);
2805 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
2806 					 unsigned len, unsigned copied,
2807 					 struct page *page);
2808 extern int ext4_try_add_inline_entry(handle_t *handle,
2809 				     struct ext4_filename *fname,
2810 				     struct dentry *dentry,
2811 				     struct inode *inode);
2812 extern int ext4_try_create_inline_dir(handle_t *handle,
2813 				      struct inode *parent,
2814 				      struct inode *inode);
2815 extern int ext4_read_inline_dir(struct file *filp,
2816 				struct dir_context *ctx,
2817 				int *has_inline_data);
2818 extern int htree_inlinedir_to_tree(struct file *dir_file,
2819 				   struct inode *dir, ext4_lblk_t block,
2820 				   struct dx_hash_info *hinfo,
2821 				   __u32 start_hash, __u32 start_minor_hash,
2822 				   int *has_inline_data);
2823 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
2824 					struct ext4_filename *fname,
2825 					const struct qstr *d_name,
2826 					struct ext4_dir_entry_2 **res_dir,
2827 					int *has_inline_data);
2828 extern int ext4_delete_inline_entry(handle_t *handle,
2829 				    struct inode *dir,
2830 				    struct ext4_dir_entry_2 *de_del,
2831 				    struct buffer_head *bh,
2832 				    int *has_inline_data);
2833 extern int empty_inline_dir(struct inode *dir, int *has_inline_data);
2834 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
2835 					struct ext4_dir_entry_2 **parent_de,
2836 					int *retval);
2837 extern int ext4_inline_data_fiemap(struct inode *inode,
2838 				   struct fiemap_extent_info *fieinfo,
2839 				   int *has_inline, __u64 start, __u64 len);
2840 extern int ext4_try_to_evict_inline_data(handle_t *handle,
2841 					 struct inode *inode,
2842 					 int needed);
2843 extern void ext4_inline_data_truncate(struct inode *inode, int *has_inline);
2844 
2845 extern int ext4_convert_inline_data(struct inode *inode);
2846 
2847 static inline int ext4_has_inline_data(struct inode *inode)
2848 {
2849 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
2850 	       EXT4_I(inode)->i_inline_off;
2851 }
2852 
2853 /* namei.c */
2854 extern const struct inode_operations ext4_dir_inode_operations;
2855 extern const struct inode_operations ext4_special_inode_operations;
2856 extern struct dentry *ext4_get_parent(struct dentry *child);
2857 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2858 				 struct ext4_dir_entry_2 *de,
2859 				 int blocksize, int csum_size,
2860 				 unsigned int parent_ino, int dotdot_real_len);
2861 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
2862 				   unsigned int blocksize);
2863 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
2864 					 struct inode *inode,
2865 					 struct buffer_head *bh);
2866 #define S_SHIFT 12
2867 static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
2868 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
2869 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
2870 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
2871 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
2872 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
2873 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
2874 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
2875 };
2876 
2877 static inline void ext4_set_de_type(struct super_block *sb,
2878 				struct ext4_dir_entry_2 *de,
2879 				umode_t mode) {
2880 	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE))
2881 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
2882 }
2883 
2884 /* readpages.c */
2885 extern int ext4_mpage_readpages(struct address_space *mapping,
2886 				struct list_head *pages, struct page *page,
2887 				unsigned nr_pages);
2888 
2889 /* symlink.c */
2890 extern const struct inode_operations ext4_symlink_inode_operations;
2891 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2892 
2893 /* block_validity */
2894 extern void ext4_release_system_zone(struct super_block *sb);
2895 extern int ext4_setup_system_zone(struct super_block *sb);
2896 extern int __init ext4_init_system_zone(void);
2897 extern void ext4_exit_system_zone(void);
2898 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2899 				 ext4_fsblk_t start_blk,
2900 				 unsigned int count);
2901 extern int ext4_check_blockref(const char *, unsigned int,
2902 			       struct inode *, __le32 *, unsigned int);
2903 
2904 /* extents.c */
2905 struct ext4_ext_path;
2906 struct ext4_extent;
2907 
2908 /*
2909  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
2910  * __le32.
2911  */
2912 #define EXT_MAX_BLOCKS	0xffffffff
2913 
2914 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2915 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2916 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
2917 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2918 			       struct ext4_map_blocks *map, int flags);
2919 extern void ext4_ext_truncate(handle_t *, struct inode *);
2920 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
2921 				 ext4_lblk_t end);
2922 extern void ext4_ext_init(struct super_block *);
2923 extern void ext4_ext_release(struct super_block *);
2924 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2925 			  loff_t len);
2926 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
2927 					  loff_t offset, ssize_t len);
2928 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2929 			   struct ext4_map_blocks *map, int flags);
2930 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
2931 					 ext4_lblk_t lblocks);
2932 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
2933 						   int num,
2934 						   struct ext4_ext_path *path);
2935 extern int ext4_can_extents_be_merged(struct inode *inode,
2936 				      struct ext4_extent *ex1,
2937 				      struct ext4_extent *ex2);
2938 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
2939 				  struct ext4_ext_path **,
2940 				  struct ext4_extent *, int);
2941 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
2942 					      struct ext4_ext_path **,
2943 					      int flags);
2944 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
2945 extern int ext4_ext_check_inode(struct inode *inode);
2946 extern int ext4_find_delalloc_range(struct inode *inode,
2947 				    ext4_lblk_t lblk_start,
2948 				    ext4_lblk_t lblk_end);
2949 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
2950 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
2951 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2952 			__u64 start, __u64 len);
2953 extern int ext4_ext_precache(struct inode *inode);
2954 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
2955 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
2956 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
2957 				struct inode *inode2, ext4_lblk_t lblk1,
2958 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
2959 			     int mark_unwritten,int *err);
2960 
2961 /* move_extent.c */
2962 extern void ext4_double_down_write_data_sem(struct inode *first,
2963 					    struct inode *second);
2964 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
2965 					  struct inode *donor_inode);
2966 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2967 			     __u64 start_orig, __u64 start_donor,
2968 			     __u64 len, __u64 *moved_len);
2969 
2970 /* page-io.c */
2971 extern int __init ext4_init_pageio(void);
2972 extern void ext4_exit_pageio(void);
2973 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2974 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
2975 extern int ext4_put_io_end(ext4_io_end_t *io_end);
2976 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
2977 extern void ext4_io_submit_init(struct ext4_io_submit *io,
2978 				struct writeback_control *wbc);
2979 extern void ext4_end_io_rsv_work(struct work_struct *work);
2980 extern void ext4_io_submit(struct ext4_io_submit *io);
2981 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2982 			       struct page *page,
2983 			       int len,
2984 			       struct writeback_control *wbc,
2985 			       bool keep_towrite);
2986 
2987 /* mmp.c */
2988 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2989 
2990 /*
2991  * Add new method to test whether block and inode bitmaps are properly
2992  * initialized. With uninit_bg reading the block from disk is not enough
2993  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2994  */
2995 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2996 
2997 static inline int bitmap_uptodate(struct buffer_head *bh)
2998 {
2999 	return (buffer_uptodate(bh) &&
3000 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3001 }
3002 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3003 {
3004 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3005 }
3006 
3007 /*
3008  * Disable DIO read nolock optimization, so new dioreaders will be forced
3009  * to grab i_mutex
3010  */
3011 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
3012 {
3013 	ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3014 	smp_mb();
3015 }
3016 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
3017 {
3018 	smp_mb();
3019 	ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3020 }
3021 
3022 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3023 
3024 /* For ioend & aio unwritten conversion wait queues */
3025 #define EXT4_WQ_HASH_SZ		37
3026 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3027 					    EXT4_WQ_HASH_SZ])
3028 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
3029 					     EXT4_WQ_HASH_SZ])
3030 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3031 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
3032 
3033 #define EXT4_RESIZING	0
3034 extern int ext4_resize_begin(struct super_block *sb);
3035 extern void ext4_resize_end(struct super_block *sb);
3036 
3037 #endif	/* __KERNEL__ */
3038 
3039 #endif	/* _EXT4_H */
3040