xref: /openbmc/linux/fs/ext4/ext4.h (revision 734f0d24)
1 /*
2  *  ext4.h
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/include/linux/minix_fs.h
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  */
15 
16 #ifndef _EXT4_H
17 #define _EXT4_H
18 
19 #include <linux/types.h>
20 #include <linux/blkdev.h>
21 #include <linux/magic.h>
22 #include <linux/jbd2.h>
23 #include <linux/quota.h>
24 #include <linux/rwsem.h>
25 #include <linux/rbtree.h>
26 #include <linux/seqlock.h>
27 #include <linux/mutex.h>
28 #include <linux/timer.h>
29 #include <linux/version.h>
30 #include <linux/wait.h>
31 #include <linux/sched/signal.h>
32 #include <linux/blockgroup_lock.h>
33 #include <linux/percpu_counter.h>
34 #include <linux/ratelimit.h>
35 #include <crypto/hash.h>
36 #include <linux/falloc.h>
37 #include <linux/percpu-rwsem.h>
38 #ifdef __KERNEL__
39 #include <linux/compat.h>
40 #endif
41 
42 #define __FS_HAS_ENCRYPTION IS_ENABLED(CONFIG_EXT4_FS_ENCRYPTION)
43 #include <linux/fscrypt.h>
44 
45 /*
46  * The fourth extended filesystem constants/structures
47  */
48 
49 /*
50  * with AGGRESSIVE_CHECK allocator runs consistency checks over
51  * structures. these checks slow things down a lot
52  */
53 #define AGGRESSIVE_CHECK__
54 
55 /*
56  * with DOUBLE_CHECK defined mballoc creates persistent in-core
57  * bitmaps, maintains and uses them to check for double allocations
58  */
59 #define DOUBLE_CHECK__
60 
61 /*
62  * Define EXT4FS_DEBUG to produce debug messages
63  */
64 #undef EXT4FS_DEBUG
65 
66 /*
67  * Debug code
68  */
69 #ifdef EXT4FS_DEBUG
70 #define ext4_debug(f, a...)						\
71 	do {								\
72 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
73 			__FILE__, __LINE__, __func__);			\
74 		printk(KERN_DEBUG f, ## a);				\
75 	} while (0)
76 #else
77 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
78 #endif
79 
80 /*
81  * Turn on EXT_DEBUG to get lots of info about extents operations.
82  */
83 #define EXT_DEBUG__
84 #ifdef EXT_DEBUG
85 #define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
86 #else
87 #define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
88 #endif
89 
90 /* data type for block offset of block group */
91 typedef int ext4_grpblk_t;
92 
93 /* data type for filesystem-wide blocks number */
94 typedef unsigned long long ext4_fsblk_t;
95 
96 /* data type for file logical block number */
97 typedef __u32 ext4_lblk_t;
98 
99 /* data type for block group number */
100 typedef unsigned int ext4_group_t;
101 
102 enum SHIFT_DIRECTION {
103 	SHIFT_LEFT = 0,
104 	SHIFT_RIGHT,
105 };
106 
107 /*
108  * Flags used in mballoc's allocation_context flags field.
109  *
110  * Also used to show what's going on for debugging purposes when the
111  * flag field is exported via the traceport interface
112  */
113 
114 /* prefer goal again. length */
115 #define EXT4_MB_HINT_MERGE		0x0001
116 /* blocks already reserved */
117 #define EXT4_MB_HINT_RESERVED		0x0002
118 /* metadata is being allocated */
119 #define EXT4_MB_HINT_METADATA		0x0004
120 /* first blocks in the file */
121 #define EXT4_MB_HINT_FIRST		0x0008
122 /* search for the best chunk */
123 #define EXT4_MB_HINT_BEST		0x0010
124 /* data is being allocated */
125 #define EXT4_MB_HINT_DATA		0x0020
126 /* don't preallocate (for tails) */
127 #define EXT4_MB_HINT_NOPREALLOC		0x0040
128 /* allocate for locality group */
129 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
130 /* allocate goal blocks or none */
131 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
132 /* goal is meaningful */
133 #define EXT4_MB_HINT_TRY_GOAL		0x0200
134 /* blocks already pre-reserved by delayed allocation */
135 #define EXT4_MB_DELALLOC_RESERVED	0x0400
136 /* We are doing stream allocation */
137 #define EXT4_MB_STREAM_ALLOC		0x0800
138 /* Use reserved root blocks if needed */
139 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
140 /* Use blocks from reserved pool */
141 #define EXT4_MB_USE_RESERVED		0x2000
142 
143 struct ext4_allocation_request {
144 	/* target inode for block we're allocating */
145 	struct inode *inode;
146 	/* how many blocks we want to allocate */
147 	unsigned int len;
148 	/* logical block in target inode */
149 	ext4_lblk_t logical;
150 	/* the closest logical allocated block to the left */
151 	ext4_lblk_t lleft;
152 	/* the closest logical allocated block to the right */
153 	ext4_lblk_t lright;
154 	/* phys. target (a hint) */
155 	ext4_fsblk_t goal;
156 	/* phys. block for the closest logical allocated block to the left */
157 	ext4_fsblk_t pleft;
158 	/* phys. block for the closest logical allocated block to the right */
159 	ext4_fsblk_t pright;
160 	/* flags. see above EXT4_MB_HINT_* */
161 	unsigned int flags;
162 };
163 
164 /*
165  * Logical to physical block mapping, used by ext4_map_blocks()
166  *
167  * This structure is used to pass requests into ext4_map_blocks() as
168  * well as to store the information returned by ext4_map_blocks().  It
169  * takes less room on the stack than a struct buffer_head.
170  */
171 #define EXT4_MAP_NEW		(1 << BH_New)
172 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
173 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
174 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
175 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
176 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
177 
178 struct ext4_map_blocks {
179 	ext4_fsblk_t m_pblk;
180 	ext4_lblk_t m_lblk;
181 	unsigned int m_len;
182 	unsigned int m_flags;
183 };
184 
185 /*
186  * Flags for ext4_io_end->flags
187  */
188 #define	EXT4_IO_END_UNWRITTEN	0x0001
189 
190 /*
191  * For converting unwritten extents on a work queue. 'handle' is used for
192  * buffered writeback.
193  */
194 typedef struct ext4_io_end {
195 	struct list_head	list;		/* per-file finished IO list */
196 	handle_t		*handle;	/* handle reserved for extent
197 						 * conversion */
198 	struct inode		*inode;		/* file being written to */
199 	struct bio		*bio;		/* Linked list of completed
200 						 * bios covering the extent */
201 	unsigned int		flag;		/* unwritten or not */
202 	atomic_t		count;		/* reference counter */
203 	loff_t			offset;		/* offset in the file */
204 	ssize_t			size;		/* size of the extent */
205 } ext4_io_end_t;
206 
207 struct ext4_io_submit {
208 	struct writeback_control *io_wbc;
209 	struct bio		*io_bio;
210 	ext4_io_end_t		*io_end;
211 	sector_t		io_next_block;
212 };
213 
214 /*
215  * Special inodes numbers
216  */
217 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
218 #define EXT4_ROOT_INO		 2	/* Root inode */
219 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
220 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
221 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
222 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
223 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
224 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
225 
226 /* First non-reserved inode for old ext4 filesystems */
227 #define EXT4_GOOD_OLD_FIRST_INO	11
228 
229 /*
230  * Maximal count of links to a file
231  */
232 #define EXT4_LINK_MAX		65000
233 
234 /*
235  * Macro-instructions used to manage several block sizes
236  */
237 #define EXT4_MIN_BLOCK_SIZE		1024
238 #define	EXT4_MAX_BLOCK_SIZE		65536
239 #define EXT4_MIN_BLOCK_LOG_SIZE		10
240 #define EXT4_MAX_BLOCK_LOG_SIZE		16
241 #define EXT4_MAX_CLUSTER_LOG_SIZE	30
242 #ifdef __KERNEL__
243 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
244 #else
245 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
246 #endif
247 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
248 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
249 					 EXT4_SB(s)->s_cluster_bits)
250 #ifdef __KERNEL__
251 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
252 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
253 #else
254 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
255 #endif
256 #ifdef __KERNEL__
257 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
258 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
259 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
260 #else
261 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
262 				 EXT4_GOOD_OLD_INODE_SIZE : \
263 				 (s)->s_inode_size)
264 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
265 				 EXT4_GOOD_OLD_FIRST_INO : \
266 				 (s)->s_first_ino)
267 #endif
268 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
269 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
270 	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
271 								  blkbits))
272 
273 /* Translate a block number to a cluster number */
274 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
275 /* Translate a cluster number to a block number */
276 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
277 /* Translate # of blks to # of clusters */
278 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
279 				 (sbi)->s_cluster_bits)
280 /* Mask out the low bits to get the starting block of the cluster */
281 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
282 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
283 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
284 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
285 /* Get the cluster offset */
286 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
287 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
288 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
289 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
290 
291 /*
292  * Structure of a blocks group descriptor
293  */
294 struct ext4_group_desc
295 {
296 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
297 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
298 	__le32	bg_inode_table_lo;	/* Inodes table block */
299 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
300 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
301 	__le16	bg_used_dirs_count_lo;	/* Directories count */
302 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
303 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
304 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
305 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
306 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
307 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
308 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
309 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
310 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
311 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
312 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
313 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
314 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
315 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
316 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
317 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
318 	__u32   bg_reserved;
319 };
320 
321 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
322 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
323 	 sizeof(__le16))
324 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
325 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
326 	 sizeof(__le16))
327 
328 /*
329  * Structure of a flex block group info
330  */
331 
332 struct flex_groups {
333 	atomic64_t	free_clusters;
334 	atomic_t	free_inodes;
335 	atomic_t	used_dirs;
336 };
337 
338 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
339 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
340 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
341 
342 /*
343  * Macro-instructions used to manage group descriptors
344  */
345 #define EXT4_MIN_DESC_SIZE		32
346 #define EXT4_MIN_DESC_SIZE_64BIT	64
347 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
348 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
349 #ifdef __KERNEL__
350 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
351 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
352 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
353 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
354 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
355 #else
356 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
357 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
358 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
359 #endif
360 
361 /*
362  * Constants relative to the data blocks
363  */
364 #define	EXT4_NDIR_BLOCKS		12
365 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
366 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
367 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
368 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
369 
370 /*
371  * Inode flags
372  */
373 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
374 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
375 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
376 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
377 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
378 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
379 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
380 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
381 /* Reserved for compression usage... */
382 #define EXT4_DIRTY_FL			0x00000100
383 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
384 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
385 	/* nb: was previously EXT2_ECOMPR_FL */
386 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
387 /* End compression flags --- maybe not all used */
388 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
389 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
390 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
391 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
392 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
393 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
394 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
395 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
396 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
397 #define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
398 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
399 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
400 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
401 
402 #define EXT4_FL_USER_VISIBLE		0x304BDFFF /* User visible flags */
403 #define EXT4_FL_USER_MODIFIABLE		0x204BC0FF /* User modifiable flags */
404 
405 /* Flags we can manipulate with through EXT4_IOC_FSSETXATTR */
406 #define EXT4_FL_XFLAG_VISIBLE		(EXT4_SYNC_FL | \
407 					 EXT4_IMMUTABLE_FL | \
408 					 EXT4_APPEND_FL | \
409 					 EXT4_NODUMP_FL | \
410 					 EXT4_NOATIME_FL | \
411 					 EXT4_PROJINHERIT_FL)
412 
413 /* Flags that should be inherited by new inodes from their parent. */
414 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
415 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
416 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
417 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
418 			   EXT4_PROJINHERIT_FL)
419 
420 /* Flags that are appropriate for regular files (all but dir-specific ones). */
421 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
422 
423 /* Flags that are appropriate for non-directories/regular files. */
424 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
425 
426 /* Mask out flags that are inappropriate for the given type of inode. */
427 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
428 {
429 	if (S_ISDIR(mode))
430 		return flags;
431 	else if (S_ISREG(mode))
432 		return flags & EXT4_REG_FLMASK;
433 	else
434 		return flags & EXT4_OTHER_FLMASK;
435 }
436 
437 /*
438  * Inode flags used for atomic set/get
439  */
440 enum {
441 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
442 	EXT4_INODE_UNRM		= 1,	/* Undelete */
443 	EXT4_INODE_COMPR	= 2,	/* Compress file */
444 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
445 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
446 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
447 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
448 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
449 /* Reserved for compression usage... */
450 	EXT4_INODE_DIRTY	= 8,
451 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
452 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
453 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
454 /* End compression flags --- maybe not all used */
455 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
456 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
457 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
458 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
459 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
460 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
461 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
462 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
463 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
464 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
465 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
466 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
467 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
468 };
469 
470 /*
471  * Since it's pretty easy to mix up bit numbers and hex values, we use a
472  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
473  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
474  * any extra space in the compiled kernel image, otherwise, the build will fail.
475  * It's important that these values are the same, since we are using
476  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
477  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
478  * values found in ext2, ext3 and ext4 filesystems, and of course the values
479  * defined in e2fsprogs.
480  *
481  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
482  */
483 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
484 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
485 
486 static inline void ext4_check_flag_values(void)
487 {
488 	CHECK_FLAG_VALUE(SECRM);
489 	CHECK_FLAG_VALUE(UNRM);
490 	CHECK_FLAG_VALUE(COMPR);
491 	CHECK_FLAG_VALUE(SYNC);
492 	CHECK_FLAG_VALUE(IMMUTABLE);
493 	CHECK_FLAG_VALUE(APPEND);
494 	CHECK_FLAG_VALUE(NODUMP);
495 	CHECK_FLAG_VALUE(NOATIME);
496 	CHECK_FLAG_VALUE(DIRTY);
497 	CHECK_FLAG_VALUE(COMPRBLK);
498 	CHECK_FLAG_VALUE(NOCOMPR);
499 	CHECK_FLAG_VALUE(ENCRYPT);
500 	CHECK_FLAG_VALUE(INDEX);
501 	CHECK_FLAG_VALUE(IMAGIC);
502 	CHECK_FLAG_VALUE(JOURNAL_DATA);
503 	CHECK_FLAG_VALUE(NOTAIL);
504 	CHECK_FLAG_VALUE(DIRSYNC);
505 	CHECK_FLAG_VALUE(TOPDIR);
506 	CHECK_FLAG_VALUE(HUGE_FILE);
507 	CHECK_FLAG_VALUE(EXTENTS);
508 	CHECK_FLAG_VALUE(EA_INODE);
509 	CHECK_FLAG_VALUE(EOFBLOCKS);
510 	CHECK_FLAG_VALUE(INLINE_DATA);
511 	CHECK_FLAG_VALUE(PROJINHERIT);
512 	CHECK_FLAG_VALUE(RESERVED);
513 }
514 
515 /* Used to pass group descriptor data when online resize is done */
516 struct ext4_new_group_input {
517 	__u32 group;		/* Group number for this data */
518 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
519 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
520 	__u64 inode_table;	/* Absolute block number of inode table start */
521 	__u32 blocks_count;	/* Total number of blocks in this group */
522 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
523 	__u16 unused;
524 };
525 
526 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
527 struct compat_ext4_new_group_input {
528 	u32 group;
529 	compat_u64 block_bitmap;
530 	compat_u64 inode_bitmap;
531 	compat_u64 inode_table;
532 	u32 blocks_count;
533 	u16 reserved_blocks;
534 	u16 unused;
535 };
536 #endif
537 
538 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
539 struct ext4_new_group_data {
540 	__u32 group;
541 	__u64 block_bitmap;
542 	__u64 inode_bitmap;
543 	__u64 inode_table;
544 	__u32 blocks_count;
545 	__u16 reserved_blocks;
546 	__u16 unused;
547 	__u32 free_blocks_count;
548 };
549 
550 /* Indexes used to index group tables in ext4_new_group_data */
551 enum {
552 	BLOCK_BITMAP = 0,	/* block bitmap */
553 	INODE_BITMAP,		/* inode bitmap */
554 	INODE_TABLE,		/* inode tables */
555 	GROUP_TABLE_COUNT,
556 };
557 
558 /*
559  * Flags used by ext4_map_blocks()
560  */
561 	/* Allocate any needed blocks and/or convert an unwritten
562 	   extent to be an initialized ext4 */
563 #define EXT4_GET_BLOCKS_CREATE			0x0001
564 	/* Request the creation of an unwritten extent */
565 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
566 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
567 						 EXT4_GET_BLOCKS_CREATE)
568 	/* Caller is from the delayed allocation writeout path
569 	 * finally doing the actual allocation of delayed blocks */
570 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
571 	/* caller is from the direct IO path, request to creation of an
572 	unwritten extents if not allocated, split the unwritten
573 	extent if blocks has been preallocated already*/
574 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
575 #define EXT4_GET_BLOCKS_CONVERT			0x0010
576 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
577 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
578 	/* Convert extent to initialized after IO complete */
579 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
580 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
581 	/* Eventual metadata allocation (due to growing extent tree)
582 	 * should not fail, so try to use reserved blocks for that.*/
583 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
584 	/* Don't normalize allocation size (used for fallocate) */
585 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
586 	/* Request will not result in inode size update (user for fallocate) */
587 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
588 	/* Convert written extents to unwritten */
589 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
590 	/* Write zeros to newly created written extents */
591 #define EXT4_GET_BLOCKS_ZERO			0x0200
592 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
593 					EXT4_GET_BLOCKS_ZERO)
594 	/* Caller will submit data before dropping transaction handle. This
595 	 * allows jbd2 to avoid submitting data before commit. */
596 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
597 
598 /*
599  * The bit position of these flags must not overlap with any of the
600  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
601  * read_extent_tree_block(), ext4_split_extent_at(),
602  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
603  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
604  * caching the extents when reading from the extent tree while a
605  * truncate or punch hole operation is in progress.
606  */
607 #define EXT4_EX_NOCACHE				0x40000000
608 #define EXT4_EX_FORCE_CACHE			0x20000000
609 
610 /*
611  * Flags used by ext4_free_blocks
612  */
613 #define EXT4_FREE_BLOCKS_METADATA	0x0001
614 #define EXT4_FREE_BLOCKS_FORGET		0x0002
615 #define EXT4_FREE_BLOCKS_VALIDATED	0x0004
616 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE	0x0008
617 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
618 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
619 
620 /*
621  * ioctl commands
622  */
623 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
624 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
625 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
626 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
627 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
628 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
629 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
630 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
631 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
632 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
633 #define EXT4_IOC_MIGRATE		_IO('f', 9)
634  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
635  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
636 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
637 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
638 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
639 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
640 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
641 #define EXT4_IOC_SET_ENCRYPTION_POLICY	FS_IOC_SET_ENCRYPTION_POLICY
642 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	FS_IOC_GET_ENCRYPTION_PWSALT
643 #define EXT4_IOC_GET_ENCRYPTION_POLICY	FS_IOC_GET_ENCRYPTION_POLICY
644 
645 #ifndef FS_IOC_FSGETXATTR
646 /* Until the uapi changes get merged for project quota... */
647 
648 #define FS_IOC_FSGETXATTR		_IOR('X', 31, struct fsxattr)
649 #define FS_IOC_FSSETXATTR		_IOW('X', 32, struct fsxattr)
650 
651 /*
652  * Structure for FS_IOC_FSGETXATTR and FS_IOC_FSSETXATTR.
653  */
654 struct fsxattr {
655 	__u32		fsx_xflags;	/* xflags field value (get/set) */
656 	__u32		fsx_extsize;	/* extsize field value (get/set)*/
657 	__u32		fsx_nextents;	/* nextents field value (get)	*/
658 	__u32		fsx_projid;	/* project identifier (get/set) */
659 	unsigned char	fsx_pad[12];
660 };
661 
662 /*
663  * Flags for the fsx_xflags field
664  */
665 #define FS_XFLAG_REALTIME	0x00000001	/* data in realtime volume */
666 #define FS_XFLAG_PREALLOC	0x00000002	/* preallocated file extents */
667 #define FS_XFLAG_IMMUTABLE	0x00000008	/* file cannot be modified */
668 #define FS_XFLAG_APPEND		0x00000010	/* all writes append */
669 #define FS_XFLAG_SYNC		0x00000020	/* all writes synchronous */
670 #define FS_XFLAG_NOATIME	0x00000040	/* do not update access time */
671 #define FS_XFLAG_NODUMP		0x00000080	/* do not include in backups */
672 #define FS_XFLAG_RTINHERIT	0x00000100	/* create with rt bit set */
673 #define FS_XFLAG_PROJINHERIT	0x00000200	/* create with parents projid */
674 #define FS_XFLAG_NOSYMLINKS	0x00000400	/* disallow symlink creation */
675 #define FS_XFLAG_EXTSIZE	0x00000800	/* extent size allocator hint */
676 #define FS_XFLAG_EXTSZINHERIT	0x00001000	/* inherit inode extent size */
677 #define FS_XFLAG_NODEFRAG	0x00002000  	/* do not defragment */
678 #define FS_XFLAG_FILESTREAM	0x00004000	/* use filestream allocator */
679 #define FS_XFLAG_HASATTR	0x80000000	/* no DIFLAG for this */
680 #endif /* !defined(FS_IOC_FSGETXATTR) */
681 
682 #define EXT4_IOC_FSGETXATTR		FS_IOC_FSGETXATTR
683 #define EXT4_IOC_FSSETXATTR		FS_IOC_FSSETXATTR
684 
685 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
686 
687 /*
688  * Flags for going down operation
689  */
690 #define EXT4_GOING_FLAGS_DEFAULT		0x0	/* going down */
691 #define EXT4_GOING_FLAGS_LOGFLUSH		0x1	/* flush log but not data */
692 #define EXT4_GOING_FLAGS_NOLOGFLUSH		0x2	/* don't flush log nor data */
693 
694 
695 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
696 /*
697  * ioctl commands in 32 bit emulation
698  */
699 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
700 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
701 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
702 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
703 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
704 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
705 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
706 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
707 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
708 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
709 #endif
710 
711 /* Max physical block we can address w/o extents */
712 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
713 
714 /*
715  * Structure of an inode on the disk
716  */
717 struct ext4_inode {
718 	__le16	i_mode;		/* File mode */
719 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
720 	__le32	i_size_lo;	/* Size in bytes */
721 	__le32	i_atime;	/* Access time */
722 	__le32	i_ctime;	/* Inode Change time */
723 	__le32	i_mtime;	/* Modification time */
724 	__le32	i_dtime;	/* Deletion Time */
725 	__le16	i_gid;		/* Low 16 bits of Group Id */
726 	__le16	i_links_count;	/* Links count */
727 	__le32	i_blocks_lo;	/* Blocks count */
728 	__le32	i_flags;	/* File flags */
729 	union {
730 		struct {
731 			__le32  l_i_version;
732 		} linux1;
733 		struct {
734 			__u32  h_i_translator;
735 		} hurd1;
736 		struct {
737 			__u32  m_i_reserved1;
738 		} masix1;
739 	} osd1;				/* OS dependent 1 */
740 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
741 	__le32	i_generation;	/* File version (for NFS) */
742 	__le32	i_file_acl_lo;	/* File ACL */
743 	__le32	i_size_high;
744 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
745 	union {
746 		struct {
747 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
748 			__le16	l_i_file_acl_high;
749 			__le16	l_i_uid_high;	/* these 2 fields */
750 			__le16	l_i_gid_high;	/* were reserved2[0] */
751 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
752 			__le16	l_i_reserved;
753 		} linux2;
754 		struct {
755 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
756 			__u16	h_i_mode_high;
757 			__u16	h_i_uid_high;
758 			__u16	h_i_gid_high;
759 			__u32	h_i_author;
760 		} hurd2;
761 		struct {
762 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
763 			__le16	m_i_file_acl_high;
764 			__u32	m_i_reserved2[2];
765 		} masix2;
766 	} osd2;				/* OS dependent 2 */
767 	__le16	i_extra_isize;
768 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
769 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
770 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
771 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
772 	__le32  i_crtime;       /* File Creation time */
773 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
774 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
775 	__le32	i_projid;	/* Project ID */
776 };
777 
778 struct move_extent {
779 	__u32 reserved;		/* should be zero */
780 	__u32 donor_fd;		/* donor file descriptor */
781 	__u64 orig_start;	/* logical start offset in block for orig */
782 	__u64 donor_start;	/* logical start offset in block for donor */
783 	__u64 len;		/* block length to be moved */
784 	__u64 moved_len;	/* moved block length */
785 };
786 
787 #define EXT4_EPOCH_BITS 2
788 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
789 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
790 
791 /*
792  * Extended fields will fit into an inode if the filesystem was formatted
793  * with large inodes (-I 256 or larger) and there are not currently any EAs
794  * consuming all of the available space. For new inodes we always reserve
795  * enough space for the kernel's known extended fields, but for inodes
796  * created with an old kernel this might not have been the case. None of
797  * the extended inode fields is critical for correct filesystem operation.
798  * This macro checks if a certain field fits in the inode. Note that
799  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
800  */
801 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
802 	((offsetof(typeof(*ext4_inode), field) +	\
803 	  sizeof((ext4_inode)->field))			\
804 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
805 	    (einode)->i_extra_isize))			\
806 
807 /*
808  * We use an encoding that preserves the times for extra epoch "00":
809  *
810  * extra  msb of                         adjust for signed
811  * epoch  32-bit                         32-bit tv_sec to
812  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
813  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
814  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
815  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
816  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
817  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
818  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
819  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
820  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
821  *
822  * Note that previous versions of the kernel on 64-bit systems would
823  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
824  * 1970.  e2fsck will correct this, assuming that it is run on the
825  * affected filesystem before 2242.
826  */
827 
828 static inline __le32 ext4_encode_extra_time(struct timespec *time)
829 {
830 	u32 extra = sizeof(time->tv_sec) > 4 ?
831 		((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK : 0;
832 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
833 }
834 
835 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
836 {
837 	if (unlikely(sizeof(time->tv_sec) > 4 &&
838 			(extra & cpu_to_le32(EXT4_EPOCH_MASK)))) {
839 
840 #if 1
841 		/* Handle legacy encoding of pre-1970 dates with epoch
842 		 * bits 1,1. (This backwards compatibility may be removed
843 		 * at the discretion of the ext4 developers.)
844 		 */
845 		u64 extra_bits = le32_to_cpu(extra) & EXT4_EPOCH_MASK;
846 		if (extra_bits == 3 && ((time->tv_sec) & 0x80000000) != 0)
847 			extra_bits = 0;
848 		time->tv_sec += extra_bits << 32;
849 #else
850 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
851 #endif
852 	}
853 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
854 }
855 
856 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)			       \
857 do {									       \
858 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	       \
859 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
860 		(raw_inode)->xtime ## _extra =				       \
861 				ext4_encode_extra_time(&(inode)->xtime);       \
862 } while (0)
863 
864 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
865 do {									       \
866 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
867 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
868 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
869 		(raw_inode)->xtime ## _extra =				       \
870 				ext4_encode_extra_time(&(einode)->xtime);      \
871 } while (0)
872 
873 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)			       \
874 do {									       \
875 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
876 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
877 		ext4_decode_extra_time(&(inode)->xtime,			       \
878 				       raw_inode->xtime ## _extra);	       \
879 	else								       \
880 		(inode)->xtime.tv_nsec = 0;				       \
881 } while (0)
882 
883 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
884 do {									       \
885 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
886 		(einode)->xtime.tv_sec = 				       \
887 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
888 	else								       \
889 		(einode)->xtime.tv_sec = 0;				       \
890 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
891 		ext4_decode_extra_time(&(einode)->xtime,		       \
892 				       raw_inode->xtime ## _extra);	       \
893 	else								       \
894 		(einode)->xtime.tv_nsec = 0;				       \
895 } while (0)
896 
897 #define i_disk_version osd1.linux1.l_i_version
898 
899 #if defined(__KERNEL__) || defined(__linux__)
900 #define i_reserved1	osd1.linux1.l_i_reserved1
901 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
902 #define i_blocks_high	osd2.linux2.l_i_blocks_high
903 #define i_uid_low	i_uid
904 #define i_gid_low	i_gid
905 #define i_uid_high	osd2.linux2.l_i_uid_high
906 #define i_gid_high	osd2.linux2.l_i_gid_high
907 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
908 
909 #elif defined(__GNU__)
910 
911 #define i_translator	osd1.hurd1.h_i_translator
912 #define i_uid_high	osd2.hurd2.h_i_uid_high
913 #define i_gid_high	osd2.hurd2.h_i_gid_high
914 #define i_author	osd2.hurd2.h_i_author
915 
916 #elif defined(__masix__)
917 
918 #define i_reserved1	osd1.masix1.m_i_reserved1
919 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
920 #define i_reserved2	osd2.masix2.m_i_reserved2
921 
922 #endif /* defined(__KERNEL__) || defined(__linux__) */
923 
924 #include "extents_status.h"
925 
926 /*
927  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
928  *
929  * These are needed to avoid lockdep false positives when we need to
930  * allocate blocks to the quota inode during ext4_map_blocks(), while
931  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
932  * do quota tracking for the quota inode, this avoids deadlock (as
933  * well as infinite recursion, since it isn't turtles all the way
934  * down...)
935  *
936  *  I_DATA_SEM_NORMAL - Used for most inodes
937  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
938  *			  where the second inode has larger inode number
939  *			  than the first
940  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
941  */
942 enum {
943 	I_DATA_SEM_NORMAL = 0,
944 	I_DATA_SEM_OTHER,
945 	I_DATA_SEM_QUOTA,
946 };
947 
948 
949 /*
950  * fourth extended file system inode data in memory
951  */
952 struct ext4_inode_info {
953 	__le32	i_data[15];	/* unconverted */
954 	__u32	i_dtime;
955 	ext4_fsblk_t	i_file_acl;
956 
957 	/*
958 	 * i_block_group is the number of the block group which contains
959 	 * this file's inode.  Constant across the lifetime of the inode,
960 	 * it is used for making block allocation decisions - we try to
961 	 * place a file's data blocks near its inode block, and new inodes
962 	 * near to their parent directory's inode.
963 	 */
964 	ext4_group_t	i_block_group;
965 	ext4_lblk_t	i_dir_start_lookup;
966 #if (BITS_PER_LONG < 64)
967 	unsigned long	i_state_flags;		/* Dynamic state flags */
968 #endif
969 	unsigned long	i_flags;
970 
971 	/*
972 	 * Extended attributes can be read independently of the main file
973 	 * data. Taking i_mutex even when reading would cause contention
974 	 * between readers of EAs and writers of regular file data, so
975 	 * instead we synchronize on xattr_sem when reading or changing
976 	 * EAs.
977 	 */
978 	struct rw_semaphore xattr_sem;
979 
980 	struct list_head i_orphan;	/* unlinked but open inodes */
981 
982 	/*
983 	 * i_disksize keeps track of what the inode size is ON DISK, not
984 	 * in memory.  During truncate, i_size is set to the new size by
985 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
986 	 * set i_disksize to 0 until the truncate is actually under way.
987 	 *
988 	 * The intent is that i_disksize always represents the blocks which
989 	 * are used by this file.  This allows recovery to restart truncate
990 	 * on orphans if we crash during truncate.  We actually write i_disksize
991 	 * into the on-disk inode when writing inodes out, instead of i_size.
992 	 *
993 	 * The only time when i_disksize and i_size may be different is when
994 	 * a truncate is in progress.  The only things which change i_disksize
995 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
996 	 */
997 	loff_t	i_disksize;
998 
999 	/*
1000 	 * i_data_sem is for serialising ext4_truncate() against
1001 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
1002 	 * data tree are chopped off during truncate. We can't do that in
1003 	 * ext4 because whenever we perform intermediate commits during
1004 	 * truncate, the inode and all the metadata blocks *must* be in a
1005 	 * consistent state which allows truncation of the orphans to restart
1006 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
1007 	 * by other means, so we have i_data_sem.
1008 	 */
1009 	struct rw_semaphore i_data_sem;
1010 	/*
1011 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
1012 	 * operations. We have to make sure that new page cannot be faulted in
1013 	 * a section of the inode that is being punched. We cannot easily use
1014 	 * i_data_sem for this since we need protection for the whole punch
1015 	 * operation and i_data_sem ranks below transaction start so we have
1016 	 * to occasionally drop it.
1017 	 */
1018 	struct rw_semaphore i_mmap_sem;
1019 	struct inode vfs_inode;
1020 	struct jbd2_inode *jinode;
1021 
1022 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
1023 
1024 	/*
1025 	 * File creation time. Its function is same as that of
1026 	 * struct timespec i_{a,c,m}time in the generic inode.
1027 	 */
1028 	struct timespec i_crtime;
1029 
1030 	/* mballoc */
1031 	struct list_head i_prealloc_list;
1032 	spinlock_t i_prealloc_lock;
1033 
1034 	/* extents status tree */
1035 	struct ext4_es_tree i_es_tree;
1036 	rwlock_t i_es_lock;
1037 	struct list_head i_es_list;
1038 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1039 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1040 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1041 					   extents to shrink. Protected by
1042 					   i_es_lock  */
1043 
1044 	/* ialloc */
1045 	ext4_group_t	i_last_alloc_group;
1046 
1047 	/* allocation reservation info for delalloc */
1048 	/* In case of bigalloc, this refer to clusters rather than blocks */
1049 	unsigned int i_reserved_data_blocks;
1050 	ext4_lblk_t i_da_metadata_calc_last_lblock;
1051 	int i_da_metadata_calc_len;
1052 
1053 	/* on-disk additional length */
1054 	__u16 i_extra_isize;
1055 
1056 	/* Indicate the inline data space. */
1057 	u16 i_inline_off;
1058 	u16 i_inline_size;
1059 
1060 #ifdef CONFIG_QUOTA
1061 	/* quota space reservation, managed internally by quota code */
1062 	qsize_t i_reserved_quota;
1063 #endif
1064 
1065 	/* Lock protecting lists below */
1066 	spinlock_t i_completed_io_lock;
1067 	/*
1068 	 * Completed IOs that need unwritten extents handling and have
1069 	 * transaction reserved
1070 	 */
1071 	struct list_head i_rsv_conversion_list;
1072 	struct work_struct i_rsv_conversion_work;
1073 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1074 
1075 	spinlock_t i_block_reservation_lock;
1076 
1077 	/*
1078 	 * Transactions that contain inode's metadata needed to complete
1079 	 * fsync and fdatasync, respectively.
1080 	 */
1081 	tid_t i_sync_tid;
1082 	tid_t i_datasync_tid;
1083 
1084 #ifdef CONFIG_QUOTA
1085 	struct dquot *i_dquot[MAXQUOTAS];
1086 #endif
1087 
1088 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1089 	__u32 i_csum_seed;
1090 
1091 	kprojid_t i_projid;
1092 };
1093 
1094 /*
1095  * File system states
1096  */
1097 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1098 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1099 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1100 
1101 /*
1102  * Misc. filesystem flags
1103  */
1104 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1105 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1106 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1107 
1108 /*
1109  * Mount flags set via mount options or defaults
1110  */
1111 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1112 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1113 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1114 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1115 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1116 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1117 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1118 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1119 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1120 #ifdef CONFIG_FS_DAX
1121 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
1122 #else
1123 #define EXT4_MOUNT_DAX			0
1124 #endif
1125 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1126 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1127 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1128 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1129 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1130 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1131 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1132 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1133 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1134 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1135 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1136 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1137 						 * enable enforcement for hidden
1138 						 * quota files */
1139 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1140 						  * enforcement for hidden quota
1141 						  * files */
1142 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1143 						  * enforcement */
1144 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1145 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1146 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1147 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1148 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1149 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1150 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1151 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1152 
1153 /*
1154  * Mount flags set either automatically (could not be set by mount option)
1155  * based on per file system feature or property or in special cases such as
1156  * distinguishing between explicit mount option definition and default.
1157  */
1158 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1159 						      specified delalloc */
1160 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1161 						      size of blocksize * 8
1162 						      blocks */
1163 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1164 						      file systems */
1165 
1166 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1167 						specified journal checksum */
1168 
1169 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1170 						~EXT4_MOUNT_##opt
1171 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1172 						EXT4_MOUNT_##opt
1173 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1174 					 EXT4_MOUNT_##opt)
1175 
1176 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1177 						~EXT4_MOUNT2_##opt
1178 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1179 						EXT4_MOUNT2_##opt
1180 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1181 					 EXT4_MOUNT2_##opt)
1182 
1183 #define ext4_test_and_set_bit		__test_and_set_bit_le
1184 #define ext4_set_bit			__set_bit_le
1185 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1186 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1187 #define ext4_clear_bit			__clear_bit_le
1188 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1189 #define ext4_test_bit			test_bit_le
1190 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1191 #define ext4_find_next_bit		find_next_bit_le
1192 
1193 extern void ext4_set_bits(void *bm, int cur, int len);
1194 
1195 /*
1196  * Maximal mount counts between two filesystem checks
1197  */
1198 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1199 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1200 
1201 /*
1202  * Behaviour when detecting errors
1203  */
1204 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1205 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1206 #define EXT4_ERRORS_PANIC		3	/* Panic */
1207 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1208 
1209 /* Metadata checksum algorithm codes */
1210 #define EXT4_CRC32C_CHKSUM		1
1211 
1212 /*
1213  * Structure of the super block
1214  */
1215 struct ext4_super_block {
1216 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1217 	__le32	s_blocks_count_lo;	/* Blocks count */
1218 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1219 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1220 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1221 	__le32	s_first_data_block;	/* First Data Block */
1222 	__le32	s_log_block_size;	/* Block size */
1223 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1224 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1225 	__le32	s_clusters_per_group;	/* # Clusters per group */
1226 	__le32	s_inodes_per_group;	/* # Inodes per group */
1227 	__le32	s_mtime;		/* Mount time */
1228 /*30*/	__le32	s_wtime;		/* Write time */
1229 	__le16	s_mnt_count;		/* Mount count */
1230 	__le16	s_max_mnt_count;	/* Maximal mount count */
1231 	__le16	s_magic;		/* Magic signature */
1232 	__le16	s_state;		/* File system state */
1233 	__le16	s_errors;		/* Behaviour when detecting errors */
1234 	__le16	s_minor_rev_level;	/* minor revision level */
1235 /*40*/	__le32	s_lastcheck;		/* time of last check */
1236 	__le32	s_checkinterval;	/* max. time between checks */
1237 	__le32	s_creator_os;		/* OS */
1238 	__le32	s_rev_level;		/* Revision level */
1239 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1240 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1241 	/*
1242 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1243 	 *
1244 	 * Note: the difference between the compatible feature set and
1245 	 * the incompatible feature set is that if there is a bit set
1246 	 * in the incompatible feature set that the kernel doesn't
1247 	 * know about, it should refuse to mount the filesystem.
1248 	 *
1249 	 * e2fsck's requirements are more strict; if it doesn't know
1250 	 * about a feature in either the compatible or incompatible
1251 	 * feature set, it must abort and not try to meddle with
1252 	 * things it doesn't understand...
1253 	 */
1254 	__le32	s_first_ino;		/* First non-reserved inode */
1255 	__le16  s_inode_size;		/* size of inode structure */
1256 	__le16	s_block_group_nr;	/* block group # of this superblock */
1257 	__le32	s_feature_compat;	/* compatible feature set */
1258 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1259 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1260 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1261 /*78*/	char	s_volume_name[16];	/* volume name */
1262 /*88*/	char	s_last_mounted[64];	/* directory where last mounted */
1263 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1264 	/*
1265 	 * Performance hints.  Directory preallocation should only
1266 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1267 	 */
1268 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1269 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1270 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1271 	/*
1272 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1273 	 */
1274 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1275 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1276 	__le32	s_journal_dev;		/* device number of journal file */
1277 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1278 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1279 	__u8	s_def_hash_version;	/* Default hash version to use */
1280 	__u8	s_jnl_backup_type;
1281 	__le16  s_desc_size;		/* size of group descriptor */
1282 /*100*/	__le32	s_default_mount_opts;
1283 	__le32	s_first_meta_bg;	/* First metablock block group */
1284 	__le32	s_mkfs_time;		/* When the filesystem was created */
1285 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1286 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1287 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1288 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1289 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1290 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1291 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1292 	__le32	s_flags;		/* Miscellaneous flags */
1293 	__le16  s_raid_stride;		/* RAID stride */
1294 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1295 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1296 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1297 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1298 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1299 	__u8	s_encryption_level;	/* versioning level for encryption */
1300 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1301 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1302 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1303 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1304 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1305 					      snapshot's future use */
1306 	__le32	s_snapshot_list;	/* inode number of the head of the
1307 					   on-disk snapshot list */
1308 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1309 	__le32	s_error_count;		/* number of fs errors */
1310 	__le32	s_first_error_time;	/* first time an error happened */
1311 	__le32	s_first_error_ino;	/* inode involved in first error */
1312 	__le64	s_first_error_block;	/* block involved of first error */
1313 	__u8	s_first_error_func[32];	/* function where the error happened */
1314 	__le32	s_first_error_line;	/* line number where error happened */
1315 	__le32	s_last_error_time;	/* most recent time of an error */
1316 	__le32	s_last_error_ino;	/* inode involved in last error */
1317 	__le32	s_last_error_line;	/* line number where error happened */
1318 	__le64	s_last_error_block;	/* block involved of last error */
1319 	__u8	s_last_error_func[32];	/* function where the error happened */
1320 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1321 	__u8	s_mount_opts[64];
1322 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1323 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1324 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1325 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1326 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1327 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1328 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1329 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1330 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1331 	__le32	s_reserved[98];		/* Padding to the end of the block */
1332 	__le32	s_checksum;		/* crc32c(superblock) */
1333 };
1334 
1335 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1336 
1337 #ifdef __KERNEL__
1338 
1339 /*
1340  * run-time mount flags
1341  */
1342 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1343 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1344 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1345 
1346 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1347 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1348 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1349 #else
1350 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1351 #endif
1352 
1353 /* Number of quota types we support */
1354 #define EXT4_MAXQUOTAS 3
1355 
1356 /*
1357  * fourth extended-fs super-block data in memory
1358  */
1359 struct ext4_sb_info {
1360 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1361 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1362 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1363 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1364 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1365 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1366 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1367 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1368 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1369 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1370 	unsigned long s_overhead;  /* # of fs overhead clusters */
1371 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1372 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1373 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1374 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1375 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1376 	struct buffer_head **s_group_desc;
1377 	unsigned int s_mount_opt;
1378 	unsigned int s_mount_opt2;
1379 	unsigned int s_mount_flags;
1380 	unsigned int s_def_mount_opt;
1381 	ext4_fsblk_t s_sb_block;
1382 	atomic64_t s_resv_clusters;
1383 	kuid_t s_resuid;
1384 	kgid_t s_resgid;
1385 	unsigned short s_mount_state;
1386 	unsigned short s_pad;
1387 	int s_addr_per_block_bits;
1388 	int s_desc_per_block_bits;
1389 	int s_inode_size;
1390 	int s_first_ino;
1391 	unsigned int s_inode_readahead_blks;
1392 	unsigned int s_inode_goal;
1393 	spinlock_t s_next_gen_lock;
1394 	u32 s_next_generation;
1395 	u32 s_hash_seed[4];
1396 	int s_def_hash_version;
1397 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1398 	struct percpu_counter s_freeclusters_counter;
1399 	struct percpu_counter s_freeinodes_counter;
1400 	struct percpu_counter s_dirs_counter;
1401 	struct percpu_counter s_dirtyclusters_counter;
1402 	struct blockgroup_lock *s_blockgroup_lock;
1403 	struct proc_dir_entry *s_proc;
1404 	struct kobject s_kobj;
1405 	struct completion s_kobj_unregister;
1406 	struct super_block *s_sb;
1407 
1408 	/* Journaling */
1409 	struct journal_s *s_journal;
1410 	struct list_head s_orphan;
1411 	struct mutex s_orphan_lock;
1412 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1413 	unsigned long s_commit_interval;
1414 	u32 s_max_batch_time;
1415 	u32 s_min_batch_time;
1416 	struct block_device *journal_bdev;
1417 #ifdef CONFIG_QUOTA
1418 	char *s_qf_names[EXT4_MAXQUOTAS];	/* Names of quota files with journalled quota */
1419 	int s_jquota_fmt;			/* Format of quota to use */
1420 #endif
1421 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1422 	struct rb_root system_blks;
1423 
1424 #ifdef EXTENTS_STATS
1425 	/* ext4 extents stats */
1426 	unsigned long s_ext_min;
1427 	unsigned long s_ext_max;
1428 	unsigned long s_depth_max;
1429 	spinlock_t s_ext_stats_lock;
1430 	unsigned long s_ext_blocks;
1431 	unsigned long s_ext_extents;
1432 #endif
1433 
1434 	/* for buddy allocator */
1435 	struct ext4_group_info ***s_group_info;
1436 	struct inode *s_buddy_cache;
1437 	spinlock_t s_md_lock;
1438 	unsigned short *s_mb_offsets;
1439 	unsigned int *s_mb_maxs;
1440 	unsigned int s_group_info_size;
1441 	unsigned int s_mb_free_pending;
1442 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1443 						   after commit completed */
1444 
1445 	/* tunables */
1446 	unsigned long s_stripe;
1447 	unsigned int s_mb_stream_request;
1448 	unsigned int s_mb_max_to_scan;
1449 	unsigned int s_mb_min_to_scan;
1450 	unsigned int s_mb_stats;
1451 	unsigned int s_mb_order2_reqs;
1452 	unsigned int s_mb_group_prealloc;
1453 	unsigned int s_max_dir_size_kb;
1454 	/* where last allocation was done - for stream allocation */
1455 	unsigned long s_mb_last_group;
1456 	unsigned long s_mb_last_start;
1457 
1458 	/* stats for buddy allocator */
1459 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1460 	atomic_t s_bal_success;	/* we found long enough chunks */
1461 	atomic_t s_bal_allocated;	/* in blocks */
1462 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1463 	atomic_t s_bal_goals;	/* goal hits */
1464 	atomic_t s_bal_breaks;	/* too long searches */
1465 	atomic_t s_bal_2orders;	/* 2^order hits */
1466 	spinlock_t s_bal_lock;
1467 	unsigned long s_mb_buddies_generated;
1468 	unsigned long long s_mb_generation_time;
1469 	atomic_t s_mb_lost_chunks;
1470 	atomic_t s_mb_preallocated;
1471 	atomic_t s_mb_discarded;
1472 	atomic_t s_lock_busy;
1473 
1474 	/* locality groups */
1475 	struct ext4_locality_group __percpu *s_locality_groups;
1476 
1477 	/* for write statistics */
1478 	unsigned long s_sectors_written_start;
1479 	u64 s_kbytes_written;
1480 
1481 	/* the size of zero-out chunk */
1482 	unsigned int s_extent_max_zeroout_kb;
1483 
1484 	unsigned int s_log_groups_per_flex;
1485 	struct flex_groups *s_flex_groups;
1486 	ext4_group_t s_flex_groups_allocated;
1487 
1488 	/* workqueue for reserved extent conversions (buffered io) */
1489 	struct workqueue_struct *rsv_conversion_wq;
1490 
1491 	/* timer for periodic error stats printing */
1492 	struct timer_list s_err_report;
1493 
1494 	/* Lazy inode table initialization info */
1495 	struct ext4_li_request *s_li_request;
1496 	/* Wait multiplier for lazy initialization thread */
1497 	unsigned int s_li_wait_mult;
1498 
1499 	/* Kernel thread for multiple mount protection */
1500 	struct task_struct *s_mmp_tsk;
1501 
1502 	/* record the last minlen when FITRIM is called. */
1503 	atomic_t s_last_trim_minblks;
1504 
1505 	/* Reference to checksum algorithm driver via cryptoapi */
1506 	struct crypto_shash *s_chksum_driver;
1507 
1508 	/* Precomputed FS UUID checksum for seeding other checksums */
1509 	__u32 s_csum_seed;
1510 
1511 	/* Reclaim extents from extent status tree */
1512 	struct shrinker s_es_shrinker;
1513 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1514 	long s_es_nr_inode;
1515 	struct ext4_es_stats s_es_stats;
1516 	struct mb_cache *s_ea_block_cache;
1517 	struct mb_cache *s_ea_inode_cache;
1518 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1519 
1520 	/* Ratelimit ext4 messages. */
1521 	struct ratelimit_state s_err_ratelimit_state;
1522 	struct ratelimit_state s_warning_ratelimit_state;
1523 	struct ratelimit_state s_msg_ratelimit_state;
1524 
1525 	/* Barrier between changing inodes' journal flags and writepages ops. */
1526 	struct percpu_rw_semaphore s_journal_flag_rwsem;
1527 	struct dax_device *s_daxdev;
1528 };
1529 
1530 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1531 {
1532 	return sb->s_fs_info;
1533 }
1534 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1535 {
1536 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1537 }
1538 
1539 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1540 {
1541 	return ino == EXT4_ROOT_INO ||
1542 		ino == EXT4_USR_QUOTA_INO ||
1543 		ino == EXT4_GRP_QUOTA_INO ||
1544 		ino == EXT4_BOOT_LOADER_INO ||
1545 		ino == EXT4_JOURNAL_INO ||
1546 		ino == EXT4_RESIZE_INO ||
1547 		(ino >= EXT4_FIRST_INO(sb) &&
1548 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1549 }
1550 
1551 /*
1552  * Inode dynamic state flags
1553  */
1554 enum {
1555 	EXT4_STATE_JDATA,		/* journaled data exists */
1556 	EXT4_STATE_NEW,			/* inode is newly created */
1557 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1558 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1559 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1560 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1561 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1562 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1563 	EXT4_STATE_DIOREAD_LOCK,	/* Disable support for dio read
1564 					   nolocking */
1565 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1566 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1567 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1568 };
1569 
1570 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1571 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1572 {									\
1573 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1574 }									\
1575 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1576 {									\
1577 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1578 }									\
1579 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1580 {									\
1581 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1582 }
1583 
1584 /* Add these declarations here only so that these functions can be
1585  * found by name.  Otherwise, they are very hard to locate. */
1586 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1587 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1588 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1589 EXT4_INODE_BIT_FNS(flag, flags, 0)
1590 
1591 /* Add these declarations here only so that these functions can be
1592  * found by name.  Otherwise, they are very hard to locate. */
1593 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1594 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1595 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1596 #if (BITS_PER_LONG < 64)
1597 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1598 
1599 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1600 {
1601 	(ei)->i_state_flags = 0;
1602 }
1603 #else
1604 EXT4_INODE_BIT_FNS(state, flags, 32)
1605 
1606 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1607 {
1608 	/* We depend on the fact that callers will set i_flags */
1609 }
1610 #endif
1611 #else
1612 /* Assume that user mode programs are passing in an ext4fs superblock, not
1613  * a kernel struct super_block.  This will allow us to call the feature-test
1614  * macros from user land. */
1615 #define EXT4_SB(sb)	(sb)
1616 #endif
1617 
1618 /*
1619  * Returns true if the inode is inode is encrypted
1620  */
1621 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1622 
1623 /*
1624  * Codes for operating systems
1625  */
1626 #define EXT4_OS_LINUX		0
1627 #define EXT4_OS_HURD		1
1628 #define EXT4_OS_MASIX		2
1629 #define EXT4_OS_FREEBSD		3
1630 #define EXT4_OS_LITES		4
1631 
1632 /*
1633  * Revision levels
1634  */
1635 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1636 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1637 
1638 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1639 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1640 
1641 #define EXT4_GOOD_OLD_INODE_SIZE 128
1642 
1643 /*
1644  * Feature set definitions
1645  */
1646 
1647 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1648 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1649 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1650 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1651 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1652 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1653 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1654 
1655 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1656 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1657 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1658 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1659 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1660 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1661 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1662 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1663 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1664 /*
1665  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1666  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1667  * all other data structures' checksums.  However, the METADATA_CSUM and
1668  * GDT_CSUM bits are mutually exclusive.
1669  */
1670 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1671 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1672 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1673 
1674 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1675 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1676 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1677 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1678 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1679 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1680 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1681 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1682 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1683 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1684 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1685 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1686 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1687 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1688 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1689 
1690 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1691 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1692 { \
1693 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1694 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1695 } \
1696 static inline void ext4_set_feature_##name(struct super_block *sb) \
1697 { \
1698 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1699 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1700 } \
1701 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1702 { \
1703 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1704 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1705 }
1706 
1707 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1708 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1709 { \
1710 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1711 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1712 } \
1713 static inline void ext4_set_feature_##name(struct super_block *sb) \
1714 { \
1715 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1716 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1717 } \
1718 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1719 { \
1720 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1721 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1722 }
1723 
1724 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1725 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1726 { \
1727 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1728 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1729 } \
1730 static inline void ext4_set_feature_##name(struct super_block *sb) \
1731 { \
1732 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
1733 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1734 } \
1735 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1736 { \
1737 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1738 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1739 }
1740 
1741 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1742 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1743 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1744 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1745 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1746 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1747 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1748 
1749 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1750 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1751 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1752 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1753 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1754 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1755 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1756 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1757 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1758 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1759 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1760 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1761 
1762 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1763 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
1764 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
1765 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
1766 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
1767 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
1768 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
1769 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
1770 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
1771 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
1772 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
1773 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
1774 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
1775 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
1776 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
1777 
1778 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1779 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1780 					 EXT4_FEATURE_INCOMPAT_META_BG)
1781 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1782 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1783 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1784 
1785 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1786 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1787 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1788 					 EXT4_FEATURE_INCOMPAT_META_BG)
1789 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1790 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1791 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1792 
1793 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1794 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1795 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1796 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1797 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1798 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1799 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1800 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
1801 					 EXT4_FEATURE_INCOMPAT_MMP | \
1802 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1803 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1804 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
1805 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
1806 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1807 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1808 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1809 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1810 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1811 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1812 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1813 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1814 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1815 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
1816 					 EXT4_FEATURE_RO_COMPAT_PROJECT)
1817 
1818 #define EXTN_FEATURE_FUNCS(ver) \
1819 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1820 { \
1821 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1822 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1823 } \
1824 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1825 { \
1826 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1827 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1828 } \
1829 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1830 { \
1831 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1832 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1833 }
1834 
1835 EXTN_FEATURE_FUNCS(2)
1836 EXTN_FEATURE_FUNCS(3)
1837 EXTN_FEATURE_FUNCS(4)
1838 
1839 static inline bool ext4_has_compat_features(struct super_block *sb)
1840 {
1841 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1842 }
1843 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1844 {
1845 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1846 }
1847 static inline bool ext4_has_incompat_features(struct super_block *sb)
1848 {
1849 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
1850 }
1851 
1852 /*
1853  * Superblock flags
1854  */
1855 #define EXT4_FLAGS_RESIZING	0
1856 #define EXT4_FLAGS_SHUTDOWN	1
1857 
1858 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
1859 {
1860 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
1861 }
1862 
1863 
1864 /*
1865  * Default values for user and/or group using reserved blocks
1866  */
1867 #define	EXT4_DEF_RESUID		0
1868 #define	EXT4_DEF_RESGID		0
1869 
1870 /*
1871  * Default project ID
1872  */
1873 #define	EXT4_DEF_PROJID		0
1874 
1875 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1876 
1877 /*
1878  * Default mount options
1879  */
1880 #define EXT4_DEFM_DEBUG		0x0001
1881 #define EXT4_DEFM_BSDGROUPS	0x0002
1882 #define EXT4_DEFM_XATTR_USER	0x0004
1883 #define EXT4_DEFM_ACL		0x0008
1884 #define EXT4_DEFM_UID16		0x0010
1885 #define EXT4_DEFM_JMODE		0x0060
1886 #define EXT4_DEFM_JMODE_DATA	0x0020
1887 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1888 #define EXT4_DEFM_JMODE_WBACK	0x0060
1889 #define EXT4_DEFM_NOBARRIER	0x0100
1890 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1891 #define EXT4_DEFM_DISCARD	0x0400
1892 #define EXT4_DEFM_NODELALLOC	0x0800
1893 
1894 /*
1895  * Default journal batch times
1896  */
1897 #define EXT4_DEF_MIN_BATCH_TIME	0
1898 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1899 
1900 /*
1901  * Minimum number of groups in a flexgroup before we separate out
1902  * directories into the first block group of a flexgroup
1903  */
1904 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1905 
1906 /*
1907  * Structure of a directory entry
1908  */
1909 #define EXT4_NAME_LEN 255
1910 
1911 struct ext4_dir_entry {
1912 	__le32	inode;			/* Inode number */
1913 	__le16	rec_len;		/* Directory entry length */
1914 	__le16	name_len;		/* Name length */
1915 	char	name[EXT4_NAME_LEN];	/* File name */
1916 };
1917 
1918 /*
1919  * The new version of the directory entry.  Since EXT4 structures are
1920  * stored in intel byte order, and the name_len field could never be
1921  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1922  * file_type field.
1923  */
1924 struct ext4_dir_entry_2 {
1925 	__le32	inode;			/* Inode number */
1926 	__le16	rec_len;		/* Directory entry length */
1927 	__u8	name_len;		/* Name length */
1928 	__u8	file_type;
1929 	char	name[EXT4_NAME_LEN];	/* File name */
1930 };
1931 
1932 /*
1933  * This is a bogus directory entry at the end of each leaf block that
1934  * records checksums.
1935  */
1936 struct ext4_dir_entry_tail {
1937 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1938 	__le16	det_rec_len;		/* 12 */
1939 	__u8	det_reserved_zero2;	/* Zero name length */
1940 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1941 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1942 };
1943 
1944 #define EXT4_DIRENT_TAIL(block, blocksize) \
1945 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1946 					((blocksize) - \
1947 					 sizeof(struct ext4_dir_entry_tail))))
1948 
1949 /*
1950  * Ext4 directory file types.  Only the low 3 bits are used.  The
1951  * other bits are reserved for now.
1952  */
1953 #define EXT4_FT_UNKNOWN		0
1954 #define EXT4_FT_REG_FILE	1
1955 #define EXT4_FT_DIR		2
1956 #define EXT4_FT_CHRDEV		3
1957 #define EXT4_FT_BLKDEV		4
1958 #define EXT4_FT_FIFO		5
1959 #define EXT4_FT_SOCK		6
1960 #define EXT4_FT_SYMLINK		7
1961 
1962 #define EXT4_FT_MAX		8
1963 
1964 #define EXT4_FT_DIR_CSUM	0xDE
1965 
1966 /*
1967  * EXT4_DIR_PAD defines the directory entries boundaries
1968  *
1969  * NOTE: It must be a multiple of 4
1970  */
1971 #define EXT4_DIR_PAD			4
1972 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1973 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1974 					 ~EXT4_DIR_ROUND)
1975 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1976 
1977 /*
1978  * If we ever get support for fs block sizes > page_size, we'll need
1979  * to remove the #if statements in the next two functions...
1980  */
1981 static inline unsigned int
1982 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1983 {
1984 	unsigned len = le16_to_cpu(dlen);
1985 
1986 #if (PAGE_SIZE >= 65536)
1987 	if (len == EXT4_MAX_REC_LEN || len == 0)
1988 		return blocksize;
1989 	return (len & 65532) | ((len & 3) << 16);
1990 #else
1991 	return len;
1992 #endif
1993 }
1994 
1995 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1996 {
1997 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1998 		BUG();
1999 #if (PAGE_SIZE >= 65536)
2000 	if (len < 65536)
2001 		return cpu_to_le16(len);
2002 	if (len == blocksize) {
2003 		if (blocksize == 65536)
2004 			return cpu_to_le16(EXT4_MAX_REC_LEN);
2005 		else
2006 			return cpu_to_le16(0);
2007 	}
2008 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2009 #else
2010 	return cpu_to_le16(len);
2011 #endif
2012 }
2013 
2014 /*
2015  * Hash Tree Directory indexing
2016  * (c) Daniel Phillips, 2001
2017  */
2018 
2019 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2020 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2021 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2022 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2023 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2024 
2025 /* Legal values for the dx_root hash_version field: */
2026 
2027 #define DX_HASH_LEGACY		0
2028 #define DX_HASH_HALF_MD4	1
2029 #define DX_HASH_TEA		2
2030 #define DX_HASH_LEGACY_UNSIGNED	3
2031 #define DX_HASH_HALF_MD4_UNSIGNED	4
2032 #define DX_HASH_TEA_UNSIGNED		5
2033 
2034 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2035 			      const void *address, unsigned int length)
2036 {
2037 	struct {
2038 		struct shash_desc shash;
2039 		char ctx[4];
2040 	} desc;
2041 	int err;
2042 
2043 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2044 
2045 	desc.shash.tfm = sbi->s_chksum_driver;
2046 	desc.shash.flags = 0;
2047 	*(u32 *)desc.ctx = crc;
2048 
2049 	err = crypto_shash_update(&desc.shash, address, length);
2050 	BUG_ON(err);
2051 
2052 	return *(u32 *)desc.ctx;
2053 }
2054 
2055 #ifdef __KERNEL__
2056 
2057 /* hash info structure used by the directory hash */
2058 struct dx_hash_info
2059 {
2060 	u32		hash;
2061 	u32		minor_hash;
2062 	int		hash_version;
2063 	u32		*seed;
2064 };
2065 
2066 
2067 /* 32 and 64 bit signed EOF for dx directories */
2068 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2069 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2070 
2071 
2072 /*
2073  * Control parameters used by ext4_htree_next_block
2074  */
2075 #define HASH_NB_ALWAYS		1
2076 
2077 struct ext4_filename {
2078 	const struct qstr *usr_fname;
2079 	struct fscrypt_str disk_name;
2080 	struct dx_hash_info hinfo;
2081 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2082 	struct fscrypt_str crypto_buf;
2083 #endif
2084 };
2085 
2086 #define fname_name(p) ((p)->disk_name.name)
2087 #define fname_len(p)  ((p)->disk_name.len)
2088 
2089 /*
2090  * Describe an inode's exact location on disk and in memory
2091  */
2092 struct ext4_iloc
2093 {
2094 	struct buffer_head *bh;
2095 	unsigned long offset;
2096 	ext4_group_t block_group;
2097 };
2098 
2099 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2100 {
2101 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2102 }
2103 
2104 static inline bool ext4_is_quota_file(struct inode *inode)
2105 {
2106 	return IS_NOQUOTA(inode) &&
2107 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2108 }
2109 
2110 /*
2111  * This structure is stuffed into the struct file's private_data field
2112  * for directories.  It is where we put information so that we can do
2113  * readdir operations in hash tree order.
2114  */
2115 struct dir_private_info {
2116 	struct rb_root	root;
2117 	struct rb_node	*curr_node;
2118 	struct fname	*extra_fname;
2119 	loff_t		last_pos;
2120 	__u32		curr_hash;
2121 	__u32		curr_minor_hash;
2122 	__u32		next_hash;
2123 };
2124 
2125 /* calculate the first block number of the group */
2126 static inline ext4_fsblk_t
2127 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2128 {
2129 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2130 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2131 }
2132 
2133 /*
2134  * Special error return code only used by dx_probe() and its callers.
2135  */
2136 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2137 
2138 /* htree levels for ext4 */
2139 #define	EXT4_HTREE_LEVEL_COMPAT	2
2140 #define	EXT4_HTREE_LEVEL	3
2141 
2142 static inline int ext4_dir_htree_level(struct super_block *sb)
2143 {
2144 	return ext4_has_feature_largedir(sb) ?
2145 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2146 }
2147 
2148 /*
2149  * Timeout and state flag for lazy initialization inode thread.
2150  */
2151 #define EXT4_DEF_LI_WAIT_MULT			10
2152 #define EXT4_DEF_LI_MAX_START_DELAY		5
2153 #define EXT4_LAZYINIT_QUIT			0x0001
2154 #define EXT4_LAZYINIT_RUNNING			0x0002
2155 
2156 /*
2157  * Lazy inode table initialization info
2158  */
2159 struct ext4_lazy_init {
2160 	unsigned long		li_state;
2161 	struct list_head	li_request_list;
2162 	struct mutex		li_list_mtx;
2163 };
2164 
2165 struct ext4_li_request {
2166 	struct super_block	*lr_super;
2167 	struct ext4_sb_info	*lr_sbi;
2168 	ext4_group_t		lr_next_group;
2169 	struct list_head	lr_request;
2170 	unsigned long		lr_next_sched;
2171 	unsigned long		lr_timeout;
2172 };
2173 
2174 struct ext4_features {
2175 	struct kobject f_kobj;
2176 	struct completion f_kobj_unregister;
2177 };
2178 
2179 /*
2180  * This structure will be used for multiple mount protection. It will be
2181  * written into the block number saved in the s_mmp_block field in the
2182  * superblock. Programs that check MMP should assume that if
2183  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2184  * to use the filesystem, regardless of how old the timestamp is.
2185  */
2186 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2187 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2188 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2189 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2190 
2191 struct mmp_struct {
2192 	__le32	mmp_magic;		/* Magic number for MMP */
2193 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2194 
2195 	/*
2196 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2197 	 * purposes and do not affect the correctness of the algorithm
2198 	 */
2199 	__le64	mmp_time;		/* Time last updated */
2200 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2201 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2202 
2203 	/*
2204 	 * mmp_check_interval is used to verify if the MMP block has been
2205 	 * updated on the block device. The value is updated based on the
2206 	 * maximum time to write the MMP block during an update cycle.
2207 	 */
2208 	__le16	mmp_check_interval;
2209 
2210 	__le16	mmp_pad1;
2211 	__le32	mmp_pad2[226];
2212 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2213 };
2214 
2215 /* arguments passed to the mmp thread */
2216 struct mmpd_data {
2217 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2218 	struct super_block *sb;  /* super block of the fs */
2219 };
2220 
2221 /*
2222  * Check interval multiplier
2223  * The MMP block is written every update interval and initially checked every
2224  * update interval x the multiplier (the value is then adapted based on the
2225  * write latency). The reason is that writes can be delayed under load and we
2226  * don't want readers to incorrectly assume that the filesystem is no longer
2227  * in use.
2228  */
2229 #define EXT4_MMP_CHECK_MULT		2UL
2230 
2231 /*
2232  * Minimum interval for MMP checking in seconds.
2233  */
2234 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2235 
2236 /*
2237  * Maximum interval for MMP checking in seconds.
2238  */
2239 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2240 
2241 /*
2242  * Function prototypes
2243  */
2244 
2245 /*
2246  * Ok, these declarations are also in <linux/kernel.h> but none of the
2247  * ext4 source programs needs to include it so they are duplicated here.
2248  */
2249 # define NORET_TYPE	/**/
2250 # define ATTRIB_NORET	__attribute__((noreturn))
2251 # define NORET_AND	noreturn,
2252 
2253 /* bitmap.c */
2254 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2255 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2256 				struct ext4_group_desc *gdp,
2257 				struct buffer_head *bh, int sz);
2258 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2259 				  struct ext4_group_desc *gdp,
2260 				  struct buffer_head *bh, int sz);
2261 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2262 				struct ext4_group_desc *gdp,
2263 				struct buffer_head *bh);
2264 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2265 				  struct ext4_group_desc *gdp,
2266 				  struct buffer_head *bh);
2267 
2268 /* balloc.c */
2269 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2270 					 ext4_fsblk_t blocknr,
2271 					 ext4_group_t *blockgrpp,
2272 					 ext4_grpblk_t *offsetp);
2273 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2274 					  ext4_fsblk_t block);
2275 
2276 extern unsigned int ext4_block_group(struct super_block *sb,
2277 			ext4_fsblk_t blocknr);
2278 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2279 			ext4_fsblk_t blocknr);
2280 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2281 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2282 			ext4_group_t group);
2283 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2284 					 ext4_fsblk_t goal,
2285 					 unsigned int flags,
2286 					 unsigned long *count,
2287 					 int *errp);
2288 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2289 				    s64 nclusters, unsigned int flags);
2290 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2291 extern void ext4_check_blocks_bitmap(struct super_block *);
2292 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2293 						    ext4_group_t block_group,
2294 						    struct buffer_head ** bh);
2295 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2296 
2297 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2298 						ext4_group_t block_group);
2299 extern int ext4_wait_block_bitmap(struct super_block *sb,
2300 				  ext4_group_t block_group,
2301 				  struct buffer_head *bh);
2302 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2303 						  ext4_group_t block_group);
2304 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2305 					      ext4_group_t block_group,
2306 					      struct ext4_group_desc *gdp);
2307 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2308 
2309 static inline bool ext4_encrypted_inode(struct inode *inode)
2310 {
2311 	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
2312 }
2313 
2314 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2315 static inline int ext4_fname_setup_filename(struct inode *dir,
2316 			const struct qstr *iname,
2317 			int lookup, struct ext4_filename *fname)
2318 {
2319 	struct fscrypt_name name;
2320 	int err;
2321 
2322 	memset(fname, 0, sizeof(struct ext4_filename));
2323 
2324 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2325 
2326 	fname->usr_fname = name.usr_fname;
2327 	fname->disk_name = name.disk_name;
2328 	fname->hinfo.hash = name.hash;
2329 	fname->hinfo.minor_hash = name.minor_hash;
2330 	fname->crypto_buf = name.crypto_buf;
2331 	return err;
2332 }
2333 
2334 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2335 {
2336 	struct fscrypt_name name;
2337 
2338 	name.crypto_buf = fname->crypto_buf;
2339 	fscrypt_free_filename(&name);
2340 
2341 	fname->crypto_buf.name = NULL;
2342 	fname->usr_fname = NULL;
2343 	fname->disk_name.name = NULL;
2344 }
2345 #else
2346 static inline int ext4_fname_setup_filename(struct inode *dir,
2347 		const struct qstr *iname,
2348 		int lookup, struct ext4_filename *fname)
2349 {
2350 	fname->usr_fname = iname;
2351 	fname->disk_name.name = (unsigned char *) iname->name;
2352 	fname->disk_name.len = iname->len;
2353 	return 0;
2354 }
2355 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2356 
2357 #endif
2358 
2359 /* dir.c */
2360 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2361 				  struct file *,
2362 				  struct ext4_dir_entry_2 *,
2363 				  struct buffer_head *, char *, int,
2364 				  unsigned int);
2365 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2366 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2367 					(de), (bh), (buf), (size), (offset)))
2368 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2369 				__u32 minor_hash,
2370 				struct ext4_dir_entry_2 *dirent,
2371 				struct fscrypt_str *ent_name);
2372 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2373 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2374 			     struct buffer_head *bh,
2375 			     void *buf, int buf_size,
2376 			     struct ext4_filename *fname,
2377 			     struct ext4_dir_entry_2 **dest_de);
2378 void ext4_insert_dentry(struct inode *inode,
2379 			struct ext4_dir_entry_2 *de,
2380 			int buf_size,
2381 			struct ext4_filename *fname);
2382 static inline void ext4_update_dx_flag(struct inode *inode)
2383 {
2384 	if (!ext4_has_feature_dir_index(inode->i_sb))
2385 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2386 }
2387 static const unsigned char ext4_filetype_table[] = {
2388 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2389 };
2390 
2391 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2392 {
2393 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2394 		return DT_UNKNOWN;
2395 
2396 	return ext4_filetype_table[filetype];
2397 }
2398 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2399 			     void *buf, int buf_size);
2400 
2401 /* fsync.c */
2402 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2403 
2404 /* hash.c */
2405 extern int ext4fs_dirhash(const char *name, int len, struct
2406 			  dx_hash_info *hinfo);
2407 
2408 /* ialloc.c */
2409 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2410 				      const struct qstr *qstr, __u32 goal,
2411 				      uid_t *owner, __u32 i_flags,
2412 				      int handle_type, unsigned int line_no,
2413 				      int nblocks);
2414 
2415 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2416 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2417 			 i_flags, 0, 0, 0)
2418 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2419 				    type, nblocks)		    \
2420 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2421 			 0, (type), __LINE__, (nblocks))
2422 
2423 
2424 extern void ext4_free_inode(handle_t *, struct inode *);
2425 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2426 extern unsigned long ext4_count_free_inodes(struct super_block *);
2427 extern unsigned long ext4_count_dirs(struct super_block *);
2428 extern void ext4_check_inodes_bitmap(struct super_block *);
2429 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2430 extern int ext4_init_inode_table(struct super_block *sb,
2431 				 ext4_group_t group, int barrier);
2432 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2433 
2434 /* mballoc.c */
2435 extern const struct file_operations ext4_seq_mb_groups_fops;
2436 extern long ext4_mb_stats;
2437 extern long ext4_mb_max_to_scan;
2438 extern int ext4_mb_init(struct super_block *);
2439 extern int ext4_mb_release(struct super_block *);
2440 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2441 				struct ext4_allocation_request *, int *);
2442 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2443 extern void ext4_discard_preallocations(struct inode *);
2444 extern int __init ext4_init_mballoc(void);
2445 extern void ext4_exit_mballoc(void);
2446 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2447 			     struct buffer_head *bh, ext4_fsblk_t block,
2448 			     unsigned long count, int flags);
2449 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2450 				   ext4_group_t ngroups);
2451 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2452 		ext4_group_t i, struct ext4_group_desc *desc);
2453 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2454 				ext4_fsblk_t block, unsigned long count);
2455 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2456 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2457 
2458 /* inode.c */
2459 int ext4_inode_is_fast_symlink(struct inode *inode);
2460 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2461 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2462 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2463 		     bool wait, struct buffer_head **bhs);
2464 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2465 			     struct buffer_head *bh_result, int create);
2466 int ext4_get_block(struct inode *inode, sector_t iblock,
2467 		   struct buffer_head *bh_result, int create);
2468 int ext4_dio_get_block(struct inode *inode, sector_t iblock,
2469 		       struct buffer_head *bh_result, int create);
2470 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2471 			   struct buffer_head *bh, int create);
2472 int ext4_walk_page_buffers(handle_t *handle,
2473 			   struct buffer_head *head,
2474 			   unsigned from,
2475 			   unsigned to,
2476 			   int *partial,
2477 			   int (*fn)(handle_t *handle,
2478 				     struct buffer_head *bh));
2479 int do_journal_get_write_access(handle_t *handle,
2480 				struct buffer_head *bh);
2481 #define FALL_BACK_TO_NONDELALLOC 1
2482 #define CONVERT_INLINE_DATA	 2
2483 
2484 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2485 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
2486 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2487 extern int  ext4_setattr(struct dentry *, struct iattr *);
2488 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2489 extern void ext4_evict_inode(struct inode *);
2490 extern void ext4_clear_inode(struct inode *);
2491 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2492 extern int  ext4_sync_inode(handle_t *, struct inode *);
2493 extern void ext4_dirty_inode(struct inode *, int);
2494 extern int ext4_change_inode_journal_flag(struct inode *, int);
2495 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2496 extern int ext4_inode_attach_jinode(struct inode *inode);
2497 extern int ext4_can_truncate(struct inode *inode);
2498 extern int ext4_truncate(struct inode *);
2499 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2500 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2501 extern void ext4_set_inode_flags(struct inode *);
2502 extern int ext4_alloc_da_blocks(struct inode *inode);
2503 extern void ext4_set_aops(struct inode *inode);
2504 extern int ext4_writepage_trans_blocks(struct inode *);
2505 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2506 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2507 			     loff_t lstart, loff_t lend);
2508 extern int ext4_page_mkwrite(struct vm_fault *vmf);
2509 extern int ext4_filemap_fault(struct vm_fault *vmf);
2510 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2511 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2512 extern void ext4_da_update_reserve_space(struct inode *inode,
2513 					int used, int quota_claim);
2514 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2515 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2516 extern int ext4_get_next_extent(struct inode *inode, ext4_lblk_t lblk,
2517 				unsigned int map_len,
2518 				struct extent_status *result);
2519 
2520 /* indirect.c */
2521 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2522 				struct ext4_map_blocks *map, int flags);
2523 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2524 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2525 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2526 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2527 				 ext4_lblk_t start, ext4_lblk_t end);
2528 
2529 /* ioctl.c */
2530 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2531 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2532 
2533 /* migrate.c */
2534 extern int ext4_ext_migrate(struct inode *);
2535 extern int ext4_ind_migrate(struct inode *inode);
2536 
2537 /* namei.c */
2538 extern int ext4_dirent_csum_verify(struct inode *inode,
2539 				   struct ext4_dir_entry *dirent);
2540 extern int ext4_orphan_add(handle_t *, struct inode *);
2541 extern int ext4_orphan_del(handle_t *, struct inode *);
2542 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2543 				__u32 start_minor_hash, __u32 *next_hash);
2544 extern int ext4_search_dir(struct buffer_head *bh,
2545 			   char *search_buf,
2546 			   int buf_size,
2547 			   struct inode *dir,
2548 			   struct ext4_filename *fname,
2549 			   unsigned int offset,
2550 			   struct ext4_dir_entry_2 **res_dir);
2551 extern int ext4_generic_delete_entry(handle_t *handle,
2552 				     struct inode *dir,
2553 				     struct ext4_dir_entry_2 *de_del,
2554 				     struct buffer_head *bh,
2555 				     void *entry_buf,
2556 				     int buf_size,
2557 				     int csum_size);
2558 extern bool ext4_empty_dir(struct inode *inode);
2559 
2560 /* resize.c */
2561 extern int ext4_group_add(struct super_block *sb,
2562 				struct ext4_new_group_data *input);
2563 extern int ext4_group_extend(struct super_block *sb,
2564 				struct ext4_super_block *es,
2565 				ext4_fsblk_t n_blocks_count);
2566 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2567 
2568 /* super.c */
2569 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2570 extern int ext4_calculate_overhead(struct super_block *sb);
2571 extern void ext4_superblock_csum_set(struct super_block *sb);
2572 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2573 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2574 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2575 				    ext4_group_t ngroup);
2576 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2577 				     char nbuf[16]);
2578 
2579 extern __printf(4, 5)
2580 void __ext4_error(struct super_block *, const char *, unsigned int,
2581 		  const char *, ...);
2582 extern __printf(5, 6)
2583 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2584 		      const char *, ...);
2585 extern __printf(5, 6)
2586 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2587 		     const char *, ...);
2588 extern void __ext4_std_error(struct super_block *, const char *,
2589 			     unsigned int, int);
2590 extern __printf(4, 5)
2591 void __ext4_abort(struct super_block *, const char *, unsigned int,
2592 		  const char *, ...);
2593 extern __printf(4, 5)
2594 void __ext4_warning(struct super_block *, const char *, unsigned int,
2595 		    const char *, ...);
2596 extern __printf(4, 5)
2597 void __ext4_warning_inode(const struct inode *inode, const char *function,
2598 			  unsigned int line, const char *fmt, ...);
2599 extern __printf(3, 4)
2600 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2601 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2602 			   const char *, unsigned int, const char *);
2603 extern __printf(7, 8)
2604 void __ext4_grp_locked_error(const char *, unsigned int,
2605 			     struct super_block *, ext4_group_t,
2606 			     unsigned long, ext4_fsblk_t,
2607 			     const char *, ...);
2608 
2609 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2610 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2611 
2612 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
2613 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2614 
2615 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2616 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2617 
2618 #ifdef CONFIG_PRINTK
2619 
2620 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2621 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2622 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2623 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2624 #define ext4_error(sb, fmt, ...)					\
2625 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2626 #define ext4_abort(sb, fmt, ...)					\
2627 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2628 #define ext4_warning(sb, fmt, ...)					\
2629 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2630 #define ext4_warning_inode(inode, fmt, ...)				\
2631 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2632 #define ext4_msg(sb, level, fmt, ...)				\
2633 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2634 #define dump_mmp_msg(sb, mmp, msg)					\
2635 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2636 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2637 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2638 				fmt, ##__VA_ARGS__)
2639 
2640 #else
2641 
2642 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2643 do {									\
2644 	no_printk(fmt, ##__VA_ARGS__);					\
2645 	__ext4_error_inode(inode, "", 0, block, " ");			\
2646 } while (0)
2647 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2648 do {									\
2649 	no_printk(fmt, ##__VA_ARGS__);					\
2650 	__ext4_error_file(file, "", 0, block, " ");			\
2651 } while (0)
2652 #define ext4_error(sb, fmt, ...)					\
2653 do {									\
2654 	no_printk(fmt, ##__VA_ARGS__);					\
2655 	__ext4_error(sb, "", 0, " ");					\
2656 } while (0)
2657 #define ext4_abort(sb, fmt, ...)					\
2658 do {									\
2659 	no_printk(fmt, ##__VA_ARGS__);					\
2660 	__ext4_abort(sb, "", 0, " ");					\
2661 } while (0)
2662 #define ext4_warning(sb, fmt, ...)					\
2663 do {									\
2664 	no_printk(fmt, ##__VA_ARGS__);					\
2665 	__ext4_warning(sb, "", 0, " ");					\
2666 } while (0)
2667 #define ext4_warning_inode(inode, fmt, ...)				\
2668 do {									\
2669 	no_printk(fmt, ##__VA_ARGS__);					\
2670 	__ext4_warning_inode(inode, "", 0, " ");			\
2671 } while (0)
2672 #define ext4_msg(sb, level, fmt, ...)					\
2673 do {									\
2674 	no_printk(fmt, ##__VA_ARGS__);					\
2675 	__ext4_msg(sb, "", " ");					\
2676 } while (0)
2677 #define dump_mmp_msg(sb, mmp, msg)					\
2678 	__dump_mmp_msg(sb, mmp, "", 0, "")
2679 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2680 do {									\
2681 	no_printk(fmt, ##__VA_ARGS__);				\
2682 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2683 } while (0)
2684 
2685 #endif
2686 
2687 extern void ext4_update_dynamic_rev(struct super_block *sb);
2688 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2689 					__u32 compat);
2690 extern int ext4_update_rocompat_feature(handle_t *handle,
2691 					struct super_block *sb,	__u32 rocompat);
2692 extern int ext4_update_incompat_feature(handle_t *handle,
2693 					struct super_block *sb,	__u32 incompat);
2694 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2695 				      struct ext4_group_desc *bg);
2696 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2697 				      struct ext4_group_desc *bg);
2698 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2699 				     struct ext4_group_desc *bg);
2700 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2701 				      struct ext4_group_desc *bg);
2702 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2703 				 struct ext4_group_desc *bg);
2704 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2705 				struct ext4_group_desc *bg);
2706 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2707 				   struct ext4_group_desc *bg);
2708 extern void ext4_block_bitmap_set(struct super_block *sb,
2709 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2710 extern void ext4_inode_bitmap_set(struct super_block *sb,
2711 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2712 extern void ext4_inode_table_set(struct super_block *sb,
2713 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2714 extern void ext4_free_group_clusters_set(struct super_block *sb,
2715 					 struct ext4_group_desc *bg,
2716 					 __u32 count);
2717 extern void ext4_free_inodes_set(struct super_block *sb,
2718 				struct ext4_group_desc *bg, __u32 count);
2719 extern void ext4_used_dirs_set(struct super_block *sb,
2720 				struct ext4_group_desc *bg, __u32 count);
2721 extern void ext4_itable_unused_set(struct super_block *sb,
2722 				   struct ext4_group_desc *bg, __u32 count);
2723 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2724 				       struct ext4_group_desc *gdp);
2725 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2726 				     struct ext4_group_desc *gdp);
2727 extern int ext4_register_li_request(struct super_block *sb,
2728 				    ext4_group_t first_not_zeroed);
2729 
2730 static inline int ext4_has_metadata_csum(struct super_block *sb)
2731 {
2732 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2733 		     !EXT4_SB(sb)->s_chksum_driver);
2734 
2735 	return ext4_has_feature_metadata_csum(sb) &&
2736 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
2737 }
2738 
2739 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2740 {
2741 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
2742 }
2743 
2744 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2745 {
2746 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2747 		le32_to_cpu(es->s_blocks_count_lo);
2748 }
2749 
2750 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2751 {
2752 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2753 		le32_to_cpu(es->s_r_blocks_count_lo);
2754 }
2755 
2756 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2757 {
2758 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2759 		le32_to_cpu(es->s_free_blocks_count_lo);
2760 }
2761 
2762 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2763 					 ext4_fsblk_t blk)
2764 {
2765 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2766 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2767 }
2768 
2769 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2770 					      ext4_fsblk_t blk)
2771 {
2772 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2773 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2774 }
2775 
2776 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2777 					   ext4_fsblk_t blk)
2778 {
2779 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2780 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2781 }
2782 
2783 static inline loff_t ext4_isize(struct super_block *sb,
2784 				struct ext4_inode *raw_inode)
2785 {
2786 	if (ext4_has_feature_largedir(sb) ||
2787 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2788 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2789 			le32_to_cpu(raw_inode->i_size_lo);
2790 
2791 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2792 }
2793 
2794 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2795 {
2796 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2797 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2798 }
2799 
2800 static inline
2801 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2802 					    ext4_group_t group)
2803 {
2804 	 struct ext4_group_info ***grp_info;
2805 	 long indexv, indexh;
2806 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2807 	 grp_info = EXT4_SB(sb)->s_group_info;
2808 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2809 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2810 	 return grp_info[indexv][indexh];
2811 }
2812 
2813 /*
2814  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2815  * the locking protocol documented in the comments of ext4_group_add()
2816  * in resize.c
2817  */
2818 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2819 {
2820 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2821 
2822 	smp_rmb();
2823 	return ngroups;
2824 }
2825 
2826 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2827 					     ext4_group_t block_group)
2828 {
2829 	return block_group >> sbi->s_log_groups_per_flex;
2830 }
2831 
2832 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2833 {
2834 	return 1 << sbi->s_log_groups_per_flex;
2835 }
2836 
2837 #define ext4_std_error(sb, errno)				\
2838 do {								\
2839 	if ((errno))						\
2840 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2841 } while (0)
2842 
2843 #ifdef CONFIG_SMP
2844 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2845  * counters. So we need to make sure we have free clusters more
2846  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2847  */
2848 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2849 #else
2850 #define EXT4_FREECLUSTERS_WATERMARK 0
2851 #endif
2852 
2853 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2854 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2855 {
2856 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2857 		     !inode_is_locked(inode));
2858 	down_write(&EXT4_I(inode)->i_data_sem);
2859 	if (newsize > EXT4_I(inode)->i_disksize)
2860 		EXT4_I(inode)->i_disksize = newsize;
2861 	up_write(&EXT4_I(inode)->i_data_sem);
2862 }
2863 
2864 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2865 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2866 {
2867 	int changed = 0;
2868 
2869 	if (newsize > inode->i_size) {
2870 		i_size_write(inode, newsize);
2871 		changed = 1;
2872 	}
2873 	if (newsize > EXT4_I(inode)->i_disksize) {
2874 		ext4_update_i_disksize(inode, newsize);
2875 		changed |= 2;
2876 	}
2877 	return changed;
2878 }
2879 
2880 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2881 				      loff_t len);
2882 
2883 struct ext4_group_info {
2884 	unsigned long   bb_state;
2885 	struct rb_root  bb_free_root;
2886 	ext4_grpblk_t	bb_first_free;	/* first free block */
2887 	ext4_grpblk_t	bb_free;	/* total free blocks */
2888 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2889 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2890 	struct          list_head bb_prealloc_list;
2891 #ifdef DOUBLE_CHECK
2892 	void            *bb_bitmap;
2893 #endif
2894 	struct rw_semaphore alloc_sem;
2895 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2896 					 * regions, index is order.
2897 					 * bb_counters[3] = 5 means
2898 					 * 5 free 8-block regions. */
2899 };
2900 
2901 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2902 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2903 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2904 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2905 
2906 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2907 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2908 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2909 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2910 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2911 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2912 
2913 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2914 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2915 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2916 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2917 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2918 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2919 
2920 #define EXT4_MAX_CONTENTION		8
2921 #define EXT4_CONTENTION_THRESHOLD	2
2922 
2923 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2924 					      ext4_group_t group)
2925 {
2926 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2927 }
2928 
2929 /*
2930  * Returns true if the filesystem is busy enough that attempts to
2931  * access the block group locks has run into contention.
2932  */
2933 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2934 {
2935 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2936 }
2937 
2938 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2939 {
2940 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2941 	if (spin_trylock(lock))
2942 		/*
2943 		 * We're able to grab the lock right away, so drop the
2944 		 * lock contention counter.
2945 		 */
2946 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2947 	else {
2948 		/*
2949 		 * The lock is busy, so bump the contention counter,
2950 		 * and then wait on the spin lock.
2951 		 */
2952 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2953 				  EXT4_MAX_CONTENTION);
2954 		spin_lock(lock);
2955 	}
2956 }
2957 
2958 static inline void ext4_unlock_group(struct super_block *sb,
2959 					ext4_group_t group)
2960 {
2961 	spin_unlock(ext4_group_lock_ptr(sb, group));
2962 }
2963 
2964 /*
2965  * Block validity checking
2966  */
2967 #define ext4_check_indirect_blockref(inode, bh)				\
2968 	ext4_check_blockref(__func__, __LINE__, inode,			\
2969 			    (__le32 *)(bh)->b_data,			\
2970 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2971 
2972 #define ext4_ind_check_inode(inode)					\
2973 	ext4_check_blockref(__func__, __LINE__, inode,			\
2974 			    EXT4_I(inode)->i_data,			\
2975 			    EXT4_NDIR_BLOCKS)
2976 
2977 /*
2978  * Inodes and files operations
2979  */
2980 
2981 /* dir.c */
2982 extern const struct file_operations ext4_dir_operations;
2983 
2984 /* file.c */
2985 extern const struct inode_operations ext4_file_inode_operations;
2986 extern const struct file_operations ext4_file_operations;
2987 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2988 
2989 /* inline.c */
2990 extern int ext4_get_max_inline_size(struct inode *inode);
2991 extern int ext4_find_inline_data_nolock(struct inode *inode);
2992 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2993 				 unsigned int len);
2994 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2995 
2996 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2997 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2998 					 struct inode *inode,
2999 					 loff_t pos, unsigned len,
3000 					 unsigned flags,
3001 					 struct page **pagep);
3002 extern int ext4_write_inline_data_end(struct inode *inode,
3003 				      loff_t pos, unsigned len,
3004 				      unsigned copied,
3005 				      struct page *page);
3006 extern struct buffer_head *
3007 ext4_journalled_write_inline_data(struct inode *inode,
3008 				  unsigned len,
3009 				  struct page *page);
3010 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3011 					   struct inode *inode,
3012 					   loff_t pos, unsigned len,
3013 					   unsigned flags,
3014 					   struct page **pagep,
3015 					   void **fsdata);
3016 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3017 					 unsigned len, unsigned copied,
3018 					 struct page *page);
3019 extern int ext4_try_add_inline_entry(handle_t *handle,
3020 				     struct ext4_filename *fname,
3021 				     struct inode *dir, struct inode *inode);
3022 extern int ext4_try_create_inline_dir(handle_t *handle,
3023 				      struct inode *parent,
3024 				      struct inode *inode);
3025 extern int ext4_read_inline_dir(struct file *filp,
3026 				struct dir_context *ctx,
3027 				int *has_inline_data);
3028 extern int htree_inlinedir_to_tree(struct file *dir_file,
3029 				   struct inode *dir, ext4_lblk_t block,
3030 				   struct dx_hash_info *hinfo,
3031 				   __u32 start_hash, __u32 start_minor_hash,
3032 				   int *has_inline_data);
3033 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3034 					struct ext4_filename *fname,
3035 					struct ext4_dir_entry_2 **res_dir,
3036 					int *has_inline_data);
3037 extern int ext4_delete_inline_entry(handle_t *handle,
3038 				    struct inode *dir,
3039 				    struct ext4_dir_entry_2 *de_del,
3040 				    struct buffer_head *bh,
3041 				    int *has_inline_data);
3042 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3043 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3044 					struct ext4_dir_entry_2 **parent_de,
3045 					int *retval);
3046 extern int ext4_inline_data_fiemap(struct inode *inode,
3047 				   struct fiemap_extent_info *fieinfo,
3048 				   int *has_inline, __u64 start, __u64 len);
3049 extern int ext4_try_to_evict_inline_data(handle_t *handle,
3050 					 struct inode *inode,
3051 					 int needed);
3052 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3053 
3054 extern int ext4_convert_inline_data(struct inode *inode);
3055 
3056 static inline int ext4_has_inline_data(struct inode *inode)
3057 {
3058 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3059 	       EXT4_I(inode)->i_inline_off;
3060 }
3061 
3062 /* namei.c */
3063 extern const struct inode_operations ext4_dir_inode_operations;
3064 extern const struct inode_operations ext4_special_inode_operations;
3065 extern struct dentry *ext4_get_parent(struct dentry *child);
3066 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3067 				 struct ext4_dir_entry_2 *de,
3068 				 int blocksize, int csum_size,
3069 				 unsigned int parent_ino, int dotdot_real_len);
3070 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
3071 				   unsigned int blocksize);
3072 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
3073 					 struct inode *inode,
3074 					 struct buffer_head *bh);
3075 #define S_SHIFT 12
3076 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3077 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3078 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3079 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3080 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3081 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3082 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3083 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3084 };
3085 
3086 static inline void ext4_set_de_type(struct super_block *sb,
3087 				struct ext4_dir_entry_2 *de,
3088 				umode_t mode) {
3089 	if (ext4_has_feature_filetype(sb))
3090 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3091 }
3092 
3093 /* readpages.c */
3094 extern int ext4_mpage_readpages(struct address_space *mapping,
3095 				struct list_head *pages, struct page *page,
3096 				unsigned nr_pages);
3097 
3098 /* symlink.c */
3099 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3100 extern const struct inode_operations ext4_symlink_inode_operations;
3101 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3102 
3103 /* sysfs.c */
3104 extern int ext4_register_sysfs(struct super_block *sb);
3105 extern void ext4_unregister_sysfs(struct super_block *sb);
3106 extern int __init ext4_init_sysfs(void);
3107 extern void ext4_exit_sysfs(void);
3108 
3109 /* block_validity */
3110 extern void ext4_release_system_zone(struct super_block *sb);
3111 extern int ext4_setup_system_zone(struct super_block *sb);
3112 extern int __init ext4_init_system_zone(void);
3113 extern void ext4_exit_system_zone(void);
3114 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3115 				 ext4_fsblk_t start_blk,
3116 				 unsigned int count);
3117 extern int ext4_check_blockref(const char *, unsigned int,
3118 			       struct inode *, __le32 *, unsigned int);
3119 
3120 /* extents.c */
3121 struct ext4_ext_path;
3122 struct ext4_extent;
3123 
3124 /*
3125  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3126  * __le32.
3127  */
3128 #define EXT_MAX_BLOCKS	0xffffffff
3129 
3130 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
3131 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
3132 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3133 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3134 			       struct ext4_map_blocks *map, int flags);
3135 extern int ext4_ext_truncate(handle_t *, struct inode *);
3136 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3137 				 ext4_lblk_t end);
3138 extern void ext4_ext_init(struct super_block *);
3139 extern void ext4_ext_release(struct super_block *);
3140 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3141 			  loff_t len);
3142 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3143 					  loff_t offset, ssize_t len);
3144 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3145 			   struct ext4_map_blocks *map, int flags);
3146 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
3147 					 ext4_lblk_t lblocks);
3148 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3149 						   int num,
3150 						   struct ext4_ext_path *path);
3151 extern int ext4_can_extents_be_merged(struct inode *inode,
3152 				      struct ext4_extent *ex1,
3153 				      struct ext4_extent *ex2);
3154 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3155 				  struct ext4_ext_path **,
3156 				  struct ext4_extent *, int);
3157 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3158 					      struct ext4_ext_path **,
3159 					      int flags);
3160 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3161 extern int ext4_ext_check_inode(struct inode *inode);
3162 extern int ext4_find_delalloc_range(struct inode *inode,
3163 				    ext4_lblk_t lblk_start,
3164 				    ext4_lblk_t lblk_end);
3165 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
3166 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3167 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3168 			__u64 start, __u64 len);
3169 extern int ext4_ext_precache(struct inode *inode);
3170 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
3171 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
3172 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3173 				struct inode *inode2, ext4_lblk_t lblk1,
3174 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3175 			     int mark_unwritten,int *err);
3176 
3177 /* move_extent.c */
3178 extern void ext4_double_down_write_data_sem(struct inode *first,
3179 					    struct inode *second);
3180 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3181 					  struct inode *donor_inode);
3182 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3183 			     __u64 start_orig, __u64 start_donor,
3184 			     __u64 len, __u64 *moved_len);
3185 
3186 /* page-io.c */
3187 extern int __init ext4_init_pageio(void);
3188 extern void ext4_exit_pageio(void);
3189 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3190 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3191 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3192 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3193 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3194 				struct writeback_control *wbc);
3195 extern void ext4_end_io_rsv_work(struct work_struct *work);
3196 extern void ext4_io_submit(struct ext4_io_submit *io);
3197 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3198 			       struct page *page,
3199 			       int len,
3200 			       struct writeback_control *wbc,
3201 			       bool keep_towrite);
3202 
3203 /* mmp.c */
3204 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3205 
3206 /*
3207  * Add new method to test whether block and inode bitmaps are properly
3208  * initialized. With uninit_bg reading the block from disk is not enough
3209  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3210  */
3211 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3212 
3213 static inline int bitmap_uptodate(struct buffer_head *bh)
3214 {
3215 	return (buffer_uptodate(bh) &&
3216 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3217 }
3218 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3219 {
3220 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3221 }
3222 
3223 /*
3224  * Disable DIO read nolock optimization, so new dioreaders will be forced
3225  * to grab i_mutex
3226  */
3227 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
3228 {
3229 	ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3230 	smp_mb();
3231 }
3232 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
3233 {
3234 	smp_mb();
3235 	ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3236 }
3237 
3238 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3239 
3240 /* For ioend & aio unwritten conversion wait queues */
3241 #define EXT4_WQ_HASH_SZ		37
3242 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3243 					    EXT4_WQ_HASH_SZ])
3244 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3245 
3246 extern int ext4_resize_begin(struct super_block *sb);
3247 extern void ext4_resize_end(struct super_block *sb);
3248 
3249 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3250 					      struct ext4_io_end *io_end)
3251 {
3252 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3253 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3254 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3255 	}
3256 }
3257 
3258 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3259 {
3260 	struct inode *inode = io_end->inode;
3261 
3262 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3263 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3264 		/* Wake up anyone waiting on unwritten extent conversion */
3265 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3266 			wake_up_all(ext4_ioend_wq(inode));
3267 	}
3268 }
3269 
3270 extern const struct iomap_ops ext4_iomap_ops;
3271 
3272 #endif	/* __KERNEL__ */
3273 
3274 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3275 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3276 
3277 #endif	/* _EXT4_H */
3278