xref: /openbmc/linux/fs/ext4/ext4.h (revision abdc644e)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  ext4.h
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/include/linux/minix_fs.h
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  */
16 
17 #ifndef _EXT4_H
18 #define _EXT4_H
19 
20 #include <linux/types.h>
21 #include <linux/blkdev.h>
22 #include <linux/magic.h>
23 #include <linux/jbd2.h>
24 #include <linux/quota.h>
25 #include <linux/rwsem.h>
26 #include <linux/rbtree.h>
27 #include <linux/seqlock.h>
28 #include <linux/mutex.h>
29 #include <linux/timer.h>
30 #include <linux/version.h>
31 #include <linux/wait.h>
32 #include <linux/sched/signal.h>
33 #include <linux/blockgroup_lock.h>
34 #include <linux/percpu_counter.h>
35 #include <linux/ratelimit.h>
36 #include <crypto/hash.h>
37 #include <linux/falloc.h>
38 #include <linux/percpu-rwsem.h>
39 #ifdef __KERNEL__
40 #include <linux/compat.h>
41 #endif
42 
43 #define __FS_HAS_ENCRYPTION IS_ENABLED(CONFIG_EXT4_FS_ENCRYPTION)
44 #include <linux/fscrypt.h>
45 
46 #include <linux/compiler.h>
47 
48 /*
49  * The fourth extended filesystem constants/structures
50  */
51 
52 /*
53  * with AGGRESSIVE_CHECK allocator runs consistency checks over
54  * structures. these checks slow things down a lot
55  */
56 #define AGGRESSIVE_CHECK__
57 
58 /*
59  * with DOUBLE_CHECK defined mballoc creates persistent in-core
60  * bitmaps, maintains and uses them to check for double allocations
61  */
62 #define DOUBLE_CHECK__
63 
64 /*
65  * Define EXT4FS_DEBUG to produce debug messages
66  */
67 #undef EXT4FS_DEBUG
68 
69 /*
70  * Debug code
71  */
72 #ifdef EXT4FS_DEBUG
73 #define ext4_debug(f, a...)						\
74 	do {								\
75 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
76 			__FILE__, __LINE__, __func__);			\
77 		printk(KERN_DEBUG f, ## a);				\
78 	} while (0)
79 #else
80 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
81 #endif
82 
83 /*
84  * Turn on EXT_DEBUG to get lots of info about extents operations.
85  */
86 #define EXT_DEBUG__
87 #ifdef EXT_DEBUG
88 #define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
89 #else
90 #define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
91 #endif
92 
93 /* data type for block offset of block group */
94 typedef int ext4_grpblk_t;
95 
96 /* data type for filesystem-wide blocks number */
97 typedef unsigned long long ext4_fsblk_t;
98 
99 /* data type for file logical block number */
100 typedef __u32 ext4_lblk_t;
101 
102 /* data type for block group number */
103 typedef unsigned int ext4_group_t;
104 
105 enum SHIFT_DIRECTION {
106 	SHIFT_LEFT = 0,
107 	SHIFT_RIGHT,
108 };
109 
110 /*
111  * Flags used in mballoc's allocation_context flags field.
112  *
113  * Also used to show what's going on for debugging purposes when the
114  * flag field is exported via the traceport interface
115  */
116 
117 /* prefer goal again. length */
118 #define EXT4_MB_HINT_MERGE		0x0001
119 /* blocks already reserved */
120 #define EXT4_MB_HINT_RESERVED		0x0002
121 /* metadata is being allocated */
122 #define EXT4_MB_HINT_METADATA		0x0004
123 /* first blocks in the file */
124 #define EXT4_MB_HINT_FIRST		0x0008
125 /* search for the best chunk */
126 #define EXT4_MB_HINT_BEST		0x0010
127 /* data is being allocated */
128 #define EXT4_MB_HINT_DATA		0x0020
129 /* don't preallocate (for tails) */
130 #define EXT4_MB_HINT_NOPREALLOC		0x0040
131 /* allocate for locality group */
132 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
133 /* allocate goal blocks or none */
134 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
135 /* goal is meaningful */
136 #define EXT4_MB_HINT_TRY_GOAL		0x0200
137 /* blocks already pre-reserved by delayed allocation */
138 #define EXT4_MB_DELALLOC_RESERVED	0x0400
139 /* We are doing stream allocation */
140 #define EXT4_MB_STREAM_ALLOC		0x0800
141 /* Use reserved root blocks if needed */
142 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
143 /* Use blocks from reserved pool */
144 #define EXT4_MB_USE_RESERVED		0x2000
145 
146 struct ext4_allocation_request {
147 	/* target inode for block we're allocating */
148 	struct inode *inode;
149 	/* how many blocks we want to allocate */
150 	unsigned int len;
151 	/* logical block in target inode */
152 	ext4_lblk_t logical;
153 	/* the closest logical allocated block to the left */
154 	ext4_lblk_t lleft;
155 	/* the closest logical allocated block to the right */
156 	ext4_lblk_t lright;
157 	/* phys. target (a hint) */
158 	ext4_fsblk_t goal;
159 	/* phys. block for the closest logical allocated block to the left */
160 	ext4_fsblk_t pleft;
161 	/* phys. block for the closest logical allocated block to the right */
162 	ext4_fsblk_t pright;
163 	/* flags. see above EXT4_MB_HINT_* */
164 	unsigned int flags;
165 };
166 
167 /*
168  * Logical to physical block mapping, used by ext4_map_blocks()
169  *
170  * This structure is used to pass requests into ext4_map_blocks() as
171  * well as to store the information returned by ext4_map_blocks().  It
172  * takes less room on the stack than a struct buffer_head.
173  */
174 #define EXT4_MAP_NEW		(1 << BH_New)
175 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
176 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
177 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
178 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
179 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
180 
181 struct ext4_map_blocks {
182 	ext4_fsblk_t m_pblk;
183 	ext4_lblk_t m_lblk;
184 	unsigned int m_len;
185 	unsigned int m_flags;
186 };
187 
188 /*
189  * Flags for ext4_io_end->flags
190  */
191 #define	EXT4_IO_END_UNWRITTEN	0x0001
192 
193 /*
194  * For converting unwritten extents on a work queue. 'handle' is used for
195  * buffered writeback.
196  */
197 typedef struct ext4_io_end {
198 	struct list_head	list;		/* per-file finished IO list */
199 	handle_t		*handle;	/* handle reserved for extent
200 						 * conversion */
201 	struct inode		*inode;		/* file being written to */
202 	struct bio		*bio;		/* Linked list of completed
203 						 * bios covering the extent */
204 	unsigned int		flag;		/* unwritten or not */
205 	atomic_t		count;		/* reference counter */
206 	loff_t			offset;		/* offset in the file */
207 	ssize_t			size;		/* size of the extent */
208 } ext4_io_end_t;
209 
210 struct ext4_io_submit {
211 	struct writeback_control *io_wbc;
212 	struct bio		*io_bio;
213 	ext4_io_end_t		*io_end;
214 	sector_t		io_next_block;
215 };
216 
217 /*
218  * Special inodes numbers
219  */
220 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
221 #define EXT4_ROOT_INO		 2	/* Root inode */
222 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
223 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
224 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
225 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
226 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
227 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
228 
229 /* First non-reserved inode for old ext4 filesystems */
230 #define EXT4_GOOD_OLD_FIRST_INO	11
231 
232 /*
233  * Maximal count of links to a file
234  */
235 #define EXT4_LINK_MAX		65000
236 
237 /*
238  * Macro-instructions used to manage several block sizes
239  */
240 #define EXT4_MIN_BLOCK_SIZE		1024
241 #define	EXT4_MAX_BLOCK_SIZE		65536
242 #define EXT4_MIN_BLOCK_LOG_SIZE		10
243 #define EXT4_MAX_BLOCK_LOG_SIZE		16
244 #define EXT4_MAX_CLUSTER_LOG_SIZE	30
245 #ifdef __KERNEL__
246 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
247 #else
248 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
249 #endif
250 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
251 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
252 					 EXT4_SB(s)->s_cluster_bits)
253 #ifdef __KERNEL__
254 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
255 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
256 #else
257 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
258 #endif
259 #ifdef __KERNEL__
260 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
261 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
262 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
263 #else
264 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
265 				 EXT4_GOOD_OLD_INODE_SIZE : \
266 				 (s)->s_inode_size)
267 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
268 				 EXT4_GOOD_OLD_FIRST_INO : \
269 				 (s)->s_first_ino)
270 #endif
271 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
272 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
273 	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
274 								  blkbits))
275 
276 /* Translate a block number to a cluster number */
277 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
278 /* Translate a cluster number to a block number */
279 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
280 /* Translate # of blks to # of clusters */
281 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
282 				 (sbi)->s_cluster_bits)
283 /* Mask out the low bits to get the starting block of the cluster */
284 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
285 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
286 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
287 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
288 /* Get the cluster offset */
289 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
290 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
291 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
292 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
293 
294 /*
295  * Structure of a blocks group descriptor
296  */
297 struct ext4_group_desc
298 {
299 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
300 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
301 	__le32	bg_inode_table_lo;	/* Inodes table block */
302 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
303 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
304 	__le16	bg_used_dirs_count_lo;	/* Directories count */
305 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
306 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
307 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
308 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
309 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
310 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
311 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
312 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
313 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
314 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
315 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
316 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
317 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
318 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
319 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
320 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
321 	__u32   bg_reserved;
322 };
323 
324 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
325 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
326 	 sizeof(__le16))
327 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
328 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
329 	 sizeof(__le16))
330 
331 /*
332  * Structure of a flex block group info
333  */
334 
335 struct flex_groups {
336 	atomic64_t	free_clusters;
337 	atomic_t	free_inodes;
338 	atomic_t	used_dirs;
339 };
340 
341 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
342 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
343 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
344 
345 /*
346  * Macro-instructions used to manage group descriptors
347  */
348 #define EXT4_MIN_DESC_SIZE		32
349 #define EXT4_MIN_DESC_SIZE_64BIT	64
350 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
351 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
352 #ifdef __KERNEL__
353 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
354 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
355 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
356 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
357 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
358 #else
359 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
360 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
361 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
362 #endif
363 
364 /*
365  * Constants relative to the data blocks
366  */
367 #define	EXT4_NDIR_BLOCKS		12
368 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
369 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
370 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
371 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
372 
373 /*
374  * Inode flags
375  */
376 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
377 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
378 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
379 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
380 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
381 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
382 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
383 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
384 /* Reserved for compression usage... */
385 #define EXT4_DIRTY_FL			0x00000100
386 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
387 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
388 	/* nb: was previously EXT2_ECOMPR_FL */
389 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
390 /* End compression flags --- maybe not all used */
391 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
392 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
393 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
394 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
395 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
396 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
397 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
398 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
399 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
400 #define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
401 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
402 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
403 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
404 
405 #define EXT4_FL_USER_VISIBLE		0x304BDFFF /* User visible flags */
406 #define EXT4_FL_USER_MODIFIABLE		0x204BC0FF /* User modifiable flags */
407 
408 /* Flags we can manipulate with through EXT4_IOC_FSSETXATTR */
409 #define EXT4_FL_XFLAG_VISIBLE		(EXT4_SYNC_FL | \
410 					 EXT4_IMMUTABLE_FL | \
411 					 EXT4_APPEND_FL | \
412 					 EXT4_NODUMP_FL | \
413 					 EXT4_NOATIME_FL | \
414 					 EXT4_PROJINHERIT_FL)
415 
416 /* Flags that should be inherited by new inodes from their parent. */
417 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
418 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
419 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
420 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
421 			   EXT4_PROJINHERIT_FL)
422 
423 /* Flags that are appropriate for regular files (all but dir-specific ones). */
424 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
425 
426 /* Flags that are appropriate for non-directories/regular files. */
427 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
428 
429 /* The only flags that should be swapped */
430 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
431 
432 /* Mask out flags that are inappropriate for the given type of inode. */
433 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
434 {
435 	if (S_ISDIR(mode))
436 		return flags;
437 	else if (S_ISREG(mode))
438 		return flags & EXT4_REG_FLMASK;
439 	else
440 		return flags & EXT4_OTHER_FLMASK;
441 }
442 
443 /*
444  * Inode flags used for atomic set/get
445  */
446 enum {
447 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
448 	EXT4_INODE_UNRM		= 1,	/* Undelete */
449 	EXT4_INODE_COMPR	= 2,	/* Compress file */
450 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
451 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
452 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
453 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
454 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
455 /* Reserved for compression usage... */
456 	EXT4_INODE_DIRTY	= 8,
457 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
458 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
459 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
460 /* End compression flags --- maybe not all used */
461 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
462 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
463 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
464 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
465 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
466 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
467 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
468 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
469 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
470 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
471 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
472 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
473 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
474 };
475 
476 /*
477  * Since it's pretty easy to mix up bit numbers and hex values, we use a
478  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
479  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
480  * any extra space in the compiled kernel image, otherwise, the build will fail.
481  * It's important that these values are the same, since we are using
482  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
483  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
484  * values found in ext2, ext3 and ext4 filesystems, and of course the values
485  * defined in e2fsprogs.
486  *
487  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
488  */
489 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
490 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
491 
492 static inline void ext4_check_flag_values(void)
493 {
494 	CHECK_FLAG_VALUE(SECRM);
495 	CHECK_FLAG_VALUE(UNRM);
496 	CHECK_FLAG_VALUE(COMPR);
497 	CHECK_FLAG_VALUE(SYNC);
498 	CHECK_FLAG_VALUE(IMMUTABLE);
499 	CHECK_FLAG_VALUE(APPEND);
500 	CHECK_FLAG_VALUE(NODUMP);
501 	CHECK_FLAG_VALUE(NOATIME);
502 	CHECK_FLAG_VALUE(DIRTY);
503 	CHECK_FLAG_VALUE(COMPRBLK);
504 	CHECK_FLAG_VALUE(NOCOMPR);
505 	CHECK_FLAG_VALUE(ENCRYPT);
506 	CHECK_FLAG_VALUE(INDEX);
507 	CHECK_FLAG_VALUE(IMAGIC);
508 	CHECK_FLAG_VALUE(JOURNAL_DATA);
509 	CHECK_FLAG_VALUE(NOTAIL);
510 	CHECK_FLAG_VALUE(DIRSYNC);
511 	CHECK_FLAG_VALUE(TOPDIR);
512 	CHECK_FLAG_VALUE(HUGE_FILE);
513 	CHECK_FLAG_VALUE(EXTENTS);
514 	CHECK_FLAG_VALUE(EA_INODE);
515 	CHECK_FLAG_VALUE(EOFBLOCKS);
516 	CHECK_FLAG_VALUE(INLINE_DATA);
517 	CHECK_FLAG_VALUE(PROJINHERIT);
518 	CHECK_FLAG_VALUE(RESERVED);
519 }
520 
521 /* Used to pass group descriptor data when online resize is done */
522 struct ext4_new_group_input {
523 	__u32 group;		/* Group number for this data */
524 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
525 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
526 	__u64 inode_table;	/* Absolute block number of inode table start */
527 	__u32 blocks_count;	/* Total number of blocks in this group */
528 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
529 	__u16 unused;
530 };
531 
532 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
533 struct compat_ext4_new_group_input {
534 	u32 group;
535 	compat_u64 block_bitmap;
536 	compat_u64 inode_bitmap;
537 	compat_u64 inode_table;
538 	u32 blocks_count;
539 	u16 reserved_blocks;
540 	u16 unused;
541 };
542 #endif
543 
544 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
545 struct ext4_new_group_data {
546 	__u32 group;
547 	__u64 block_bitmap;
548 	__u64 inode_bitmap;
549 	__u64 inode_table;
550 	__u32 blocks_count;
551 	__u16 reserved_blocks;
552 	__u16 mdata_blocks;
553 	__u32 free_clusters_count;
554 };
555 
556 /* Indexes used to index group tables in ext4_new_group_data */
557 enum {
558 	BLOCK_BITMAP = 0,	/* block bitmap */
559 	INODE_BITMAP,		/* inode bitmap */
560 	INODE_TABLE,		/* inode tables */
561 	GROUP_TABLE_COUNT,
562 };
563 
564 /*
565  * Flags used by ext4_map_blocks()
566  */
567 	/* Allocate any needed blocks and/or convert an unwritten
568 	   extent to be an initialized ext4 */
569 #define EXT4_GET_BLOCKS_CREATE			0x0001
570 	/* Request the creation of an unwritten extent */
571 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
572 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
573 						 EXT4_GET_BLOCKS_CREATE)
574 	/* Caller is from the delayed allocation writeout path
575 	 * finally doing the actual allocation of delayed blocks */
576 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
577 	/* caller is from the direct IO path, request to creation of an
578 	unwritten extents if not allocated, split the unwritten
579 	extent if blocks has been preallocated already*/
580 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
581 #define EXT4_GET_BLOCKS_CONVERT			0x0010
582 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
583 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
584 	/* Convert extent to initialized after IO complete */
585 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
586 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
587 	/* Eventual metadata allocation (due to growing extent tree)
588 	 * should not fail, so try to use reserved blocks for that.*/
589 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
590 	/* Don't normalize allocation size (used for fallocate) */
591 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
592 	/* Request will not result in inode size update (user for fallocate) */
593 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
594 	/* Convert written extents to unwritten */
595 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
596 	/* Write zeros to newly created written extents */
597 #define EXT4_GET_BLOCKS_ZERO			0x0200
598 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
599 					EXT4_GET_BLOCKS_ZERO)
600 	/* Caller will submit data before dropping transaction handle. This
601 	 * allows jbd2 to avoid submitting data before commit. */
602 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
603 
604 /*
605  * The bit position of these flags must not overlap with any of the
606  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
607  * read_extent_tree_block(), ext4_split_extent_at(),
608  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
609  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
610  * caching the extents when reading from the extent tree while a
611  * truncate or punch hole operation is in progress.
612  */
613 #define EXT4_EX_NOCACHE				0x40000000
614 #define EXT4_EX_FORCE_CACHE			0x20000000
615 
616 /*
617  * Flags used by ext4_free_blocks
618  */
619 #define EXT4_FREE_BLOCKS_METADATA		0x0001
620 #define EXT4_FREE_BLOCKS_FORGET			0x0002
621 #define EXT4_FREE_BLOCKS_VALIDATED		0x0004
622 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE		0x0008
623 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
624 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
625 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
626 
627 /*
628  * ioctl commands
629  */
630 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
631 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
632 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
633 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
634 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
635 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
636 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
637 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
638 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
639 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
640 #define EXT4_IOC_MIGRATE		_IO('f', 9)
641  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
642  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
643 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
644 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
645 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
646 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
647 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
648 #define EXT4_IOC_SET_ENCRYPTION_POLICY	FS_IOC_SET_ENCRYPTION_POLICY
649 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	FS_IOC_GET_ENCRYPTION_PWSALT
650 #define EXT4_IOC_GET_ENCRYPTION_POLICY	FS_IOC_GET_ENCRYPTION_POLICY
651 
652 #define EXT4_IOC_FSGETXATTR		FS_IOC_FSGETXATTR
653 #define EXT4_IOC_FSSETXATTR		FS_IOC_FSSETXATTR
654 
655 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
656 
657 /*
658  * Flags for going down operation
659  */
660 #define EXT4_GOING_FLAGS_DEFAULT		0x0	/* going down */
661 #define EXT4_GOING_FLAGS_LOGFLUSH		0x1	/* flush log but not data */
662 #define EXT4_GOING_FLAGS_NOLOGFLUSH		0x2	/* don't flush log nor data */
663 
664 
665 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
666 /*
667  * ioctl commands in 32 bit emulation
668  */
669 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
670 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
671 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
672 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
673 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
674 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
675 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
676 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
677 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
678 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
679 #endif
680 
681 /* Max physical block we can address w/o extents */
682 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
683 
684 /* Max logical block we can support */
685 #define EXT4_MAX_LOGICAL_BLOCK		0xFFFFFFFF
686 
687 /*
688  * Structure of an inode on the disk
689  */
690 struct ext4_inode {
691 	__le16	i_mode;		/* File mode */
692 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
693 	__le32	i_size_lo;	/* Size in bytes */
694 	__le32	i_atime;	/* Access time */
695 	__le32	i_ctime;	/* Inode Change time */
696 	__le32	i_mtime;	/* Modification time */
697 	__le32	i_dtime;	/* Deletion Time */
698 	__le16	i_gid;		/* Low 16 bits of Group Id */
699 	__le16	i_links_count;	/* Links count */
700 	__le32	i_blocks_lo;	/* Blocks count */
701 	__le32	i_flags;	/* File flags */
702 	union {
703 		struct {
704 			__le32  l_i_version;
705 		} linux1;
706 		struct {
707 			__u32  h_i_translator;
708 		} hurd1;
709 		struct {
710 			__u32  m_i_reserved1;
711 		} masix1;
712 	} osd1;				/* OS dependent 1 */
713 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
714 	__le32	i_generation;	/* File version (for NFS) */
715 	__le32	i_file_acl_lo;	/* File ACL */
716 	__le32	i_size_high;
717 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
718 	union {
719 		struct {
720 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
721 			__le16	l_i_file_acl_high;
722 			__le16	l_i_uid_high;	/* these 2 fields */
723 			__le16	l_i_gid_high;	/* were reserved2[0] */
724 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
725 			__le16	l_i_reserved;
726 		} linux2;
727 		struct {
728 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
729 			__u16	h_i_mode_high;
730 			__u16	h_i_uid_high;
731 			__u16	h_i_gid_high;
732 			__u32	h_i_author;
733 		} hurd2;
734 		struct {
735 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
736 			__le16	m_i_file_acl_high;
737 			__u32	m_i_reserved2[2];
738 		} masix2;
739 	} osd2;				/* OS dependent 2 */
740 	__le16	i_extra_isize;
741 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
742 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
743 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
744 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
745 	__le32  i_crtime;       /* File Creation time */
746 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
747 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
748 	__le32	i_projid;	/* Project ID */
749 };
750 
751 struct move_extent {
752 	__u32 reserved;		/* should be zero */
753 	__u32 donor_fd;		/* donor file descriptor */
754 	__u64 orig_start;	/* logical start offset in block for orig */
755 	__u64 donor_start;	/* logical start offset in block for donor */
756 	__u64 len;		/* block length to be moved */
757 	__u64 moved_len;	/* moved block length */
758 };
759 
760 #define EXT4_EPOCH_BITS 2
761 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
762 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
763 
764 /*
765  * Extended fields will fit into an inode if the filesystem was formatted
766  * with large inodes (-I 256 or larger) and there are not currently any EAs
767  * consuming all of the available space. For new inodes we always reserve
768  * enough space for the kernel's known extended fields, but for inodes
769  * created with an old kernel this might not have been the case. None of
770  * the extended inode fields is critical for correct filesystem operation.
771  * This macro checks if a certain field fits in the inode. Note that
772  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
773  */
774 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
775 	((offsetof(typeof(*ext4_inode), field) +	\
776 	  sizeof((ext4_inode)->field))			\
777 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
778 	    (einode)->i_extra_isize))			\
779 
780 /*
781  * We use an encoding that preserves the times for extra epoch "00":
782  *
783  * extra  msb of                         adjust for signed
784  * epoch  32-bit                         32-bit tv_sec to
785  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
786  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
787  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
788  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
789  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
790  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
791  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
792  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
793  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
794  *
795  * Note that previous versions of the kernel on 64-bit systems would
796  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
797  * 1970.  e2fsck will correct this, assuming that it is run on the
798  * affected filesystem before 2242.
799  */
800 
801 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
802 {
803 	u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
804 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
805 }
806 
807 static inline void ext4_decode_extra_time(struct timespec64 *time,
808 					  __le32 extra)
809 {
810 	if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK))) {
811 
812 #if 1
813 		/* Handle legacy encoding of pre-1970 dates with epoch
814 		 * bits 1,1. (This backwards compatibility may be removed
815 		 * at the discretion of the ext4 developers.)
816 		 */
817 		u64 extra_bits = le32_to_cpu(extra) & EXT4_EPOCH_MASK;
818 		if (extra_bits == 3 && ((time->tv_sec) & 0x80000000) != 0)
819 			extra_bits = 0;
820 		time->tv_sec += extra_bits << 32;
821 #else
822 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
823 #endif
824 	}
825 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
826 }
827 
828 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)				\
829 do {										\
830 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);		\
831 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
832 		(raw_inode)->xtime ## _extra =					\
833 				ext4_encode_extra_time(&(inode)->xtime);	\
834 		}								\
835 } while (0)
836 
837 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
838 do {									       \
839 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
840 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
841 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
842 		(raw_inode)->xtime ## _extra =				       \
843 				ext4_encode_extra_time(&(einode)->xtime);      \
844 } while (0)
845 
846 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)				\
847 do {										\
848 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);	\
849 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {	\
850 		ext4_decode_extra_time(&(inode)->xtime,				\
851 				       raw_inode->xtime ## _extra);		\
852 		}								\
853 	else									\
854 		(inode)->xtime.tv_nsec = 0;					\
855 } while (0)
856 
857 
858 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
859 do {									       \
860 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
861 		(einode)->xtime.tv_sec = 				       \
862 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
863 	else								       \
864 		(einode)->xtime.tv_sec = 0;				       \
865 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
866 		ext4_decode_extra_time(&(einode)->xtime,		       \
867 				       raw_inode->xtime ## _extra);	       \
868 	else								       \
869 		(einode)->xtime.tv_nsec = 0;				       \
870 } while (0)
871 
872 #define i_disk_version osd1.linux1.l_i_version
873 
874 #if defined(__KERNEL__) || defined(__linux__)
875 #define i_reserved1	osd1.linux1.l_i_reserved1
876 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
877 #define i_blocks_high	osd2.linux2.l_i_blocks_high
878 #define i_uid_low	i_uid
879 #define i_gid_low	i_gid
880 #define i_uid_high	osd2.linux2.l_i_uid_high
881 #define i_gid_high	osd2.linux2.l_i_gid_high
882 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
883 
884 #elif defined(__GNU__)
885 
886 #define i_translator	osd1.hurd1.h_i_translator
887 #define i_uid_high	osd2.hurd2.h_i_uid_high
888 #define i_gid_high	osd2.hurd2.h_i_gid_high
889 #define i_author	osd2.hurd2.h_i_author
890 
891 #elif defined(__masix__)
892 
893 #define i_reserved1	osd1.masix1.m_i_reserved1
894 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
895 #define i_reserved2	osd2.masix2.m_i_reserved2
896 
897 #endif /* defined(__KERNEL__) || defined(__linux__) */
898 
899 #include "extents_status.h"
900 
901 /*
902  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
903  *
904  * These are needed to avoid lockdep false positives when we need to
905  * allocate blocks to the quota inode during ext4_map_blocks(), while
906  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
907  * do quota tracking for the quota inode, this avoids deadlock (as
908  * well as infinite recursion, since it isn't turtles all the way
909  * down...)
910  *
911  *  I_DATA_SEM_NORMAL - Used for most inodes
912  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
913  *			  where the second inode has larger inode number
914  *			  than the first
915  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
916  */
917 enum {
918 	I_DATA_SEM_NORMAL = 0,
919 	I_DATA_SEM_OTHER,
920 	I_DATA_SEM_QUOTA,
921 };
922 
923 
924 /*
925  * fourth extended file system inode data in memory
926  */
927 struct ext4_inode_info {
928 	__le32	i_data[15];	/* unconverted */
929 	__u32	i_dtime;
930 	ext4_fsblk_t	i_file_acl;
931 
932 	/*
933 	 * i_block_group is the number of the block group which contains
934 	 * this file's inode.  Constant across the lifetime of the inode,
935 	 * it is used for making block allocation decisions - we try to
936 	 * place a file's data blocks near its inode block, and new inodes
937 	 * near to their parent directory's inode.
938 	 */
939 	ext4_group_t	i_block_group;
940 	ext4_lblk_t	i_dir_start_lookup;
941 #if (BITS_PER_LONG < 64)
942 	unsigned long	i_state_flags;		/* Dynamic state flags */
943 #endif
944 	unsigned long	i_flags;
945 
946 	/*
947 	 * Extended attributes can be read independently of the main file
948 	 * data. Taking i_mutex even when reading would cause contention
949 	 * between readers of EAs and writers of regular file data, so
950 	 * instead we synchronize on xattr_sem when reading or changing
951 	 * EAs.
952 	 */
953 	struct rw_semaphore xattr_sem;
954 
955 	struct list_head i_orphan;	/* unlinked but open inodes */
956 
957 	/*
958 	 * i_disksize keeps track of what the inode size is ON DISK, not
959 	 * in memory.  During truncate, i_size is set to the new size by
960 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
961 	 * set i_disksize to 0 until the truncate is actually under way.
962 	 *
963 	 * The intent is that i_disksize always represents the blocks which
964 	 * are used by this file.  This allows recovery to restart truncate
965 	 * on orphans if we crash during truncate.  We actually write i_disksize
966 	 * into the on-disk inode when writing inodes out, instead of i_size.
967 	 *
968 	 * The only time when i_disksize and i_size may be different is when
969 	 * a truncate is in progress.  The only things which change i_disksize
970 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
971 	 */
972 	loff_t	i_disksize;
973 
974 	/*
975 	 * i_data_sem is for serialising ext4_truncate() against
976 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
977 	 * data tree are chopped off during truncate. We can't do that in
978 	 * ext4 because whenever we perform intermediate commits during
979 	 * truncate, the inode and all the metadata blocks *must* be in a
980 	 * consistent state which allows truncation of the orphans to restart
981 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
982 	 * by other means, so we have i_data_sem.
983 	 */
984 	struct rw_semaphore i_data_sem;
985 	/*
986 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
987 	 * operations. We have to make sure that new page cannot be faulted in
988 	 * a section of the inode that is being punched. We cannot easily use
989 	 * i_data_sem for this since we need protection for the whole punch
990 	 * operation and i_data_sem ranks below transaction start so we have
991 	 * to occasionally drop it.
992 	 */
993 	struct rw_semaphore i_mmap_sem;
994 	struct inode vfs_inode;
995 	struct jbd2_inode *jinode;
996 
997 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
998 
999 	/*
1000 	 * File creation time. Its function is same as that of
1001 	 * struct timespec64 i_{a,c,m}time in the generic inode.
1002 	 */
1003 	struct timespec64 i_crtime;
1004 
1005 	/* mballoc */
1006 	struct list_head i_prealloc_list;
1007 	spinlock_t i_prealloc_lock;
1008 
1009 	/* extents status tree */
1010 	struct ext4_es_tree i_es_tree;
1011 	rwlock_t i_es_lock;
1012 	struct list_head i_es_list;
1013 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1014 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1015 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1016 					   extents to shrink. Protected by
1017 					   i_es_lock  */
1018 
1019 	/* ialloc */
1020 	ext4_group_t	i_last_alloc_group;
1021 
1022 	/* allocation reservation info for delalloc */
1023 	/* In case of bigalloc, this refer to clusters rather than blocks */
1024 	unsigned int i_reserved_data_blocks;
1025 	ext4_lblk_t i_da_metadata_calc_last_lblock;
1026 	int i_da_metadata_calc_len;
1027 
1028 	/* pending cluster reservations for bigalloc file systems */
1029 	struct ext4_pending_tree i_pending_tree;
1030 
1031 	/* on-disk additional length */
1032 	__u16 i_extra_isize;
1033 
1034 	/* Indicate the inline data space. */
1035 	u16 i_inline_off;
1036 	u16 i_inline_size;
1037 
1038 #ifdef CONFIG_QUOTA
1039 	/* quota space reservation, managed internally by quota code */
1040 	qsize_t i_reserved_quota;
1041 #endif
1042 
1043 	/* Lock protecting lists below */
1044 	spinlock_t i_completed_io_lock;
1045 	/*
1046 	 * Completed IOs that need unwritten extents handling and have
1047 	 * transaction reserved
1048 	 */
1049 	struct list_head i_rsv_conversion_list;
1050 	struct work_struct i_rsv_conversion_work;
1051 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1052 
1053 	spinlock_t i_block_reservation_lock;
1054 
1055 	/*
1056 	 * Transactions that contain inode's metadata needed to complete
1057 	 * fsync and fdatasync, respectively.
1058 	 */
1059 	tid_t i_sync_tid;
1060 	tid_t i_datasync_tid;
1061 
1062 #ifdef CONFIG_QUOTA
1063 	struct dquot *i_dquot[MAXQUOTAS];
1064 #endif
1065 
1066 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1067 	__u32 i_csum_seed;
1068 
1069 	kprojid_t i_projid;
1070 };
1071 
1072 /*
1073  * File system states
1074  */
1075 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1076 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1077 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1078 
1079 /*
1080  * Misc. filesystem flags
1081  */
1082 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1083 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1084 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1085 
1086 /*
1087  * Mount flags set via mount options or defaults
1088  */
1089 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1090 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1091 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1092 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1093 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1094 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1095 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1096 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1097 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1098 #ifdef CONFIG_FS_DAX
1099 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
1100 #else
1101 #define EXT4_MOUNT_DAX			0
1102 #endif
1103 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1104 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1105 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1106 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1107 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1108 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1109 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1110 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1111 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1112 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1113 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1114 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1115 						 * enable enforcement for hidden
1116 						 * quota files */
1117 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1118 						  * enforcement for hidden quota
1119 						  * files */
1120 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1121 						  * enforcement */
1122 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1123 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1124 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1125 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
1126 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1127 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1128 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1129 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1130 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1131 
1132 /*
1133  * Mount flags set either automatically (could not be set by mount option)
1134  * based on per file system feature or property or in special cases such as
1135  * distinguishing between explicit mount option definition and default.
1136  */
1137 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1138 						      specified delalloc */
1139 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1140 						      size of blocksize * 8
1141 						      blocks */
1142 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1143 						      file systems */
1144 
1145 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1146 						specified journal checksum */
1147 
1148 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1149 						~EXT4_MOUNT_##opt
1150 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1151 						EXT4_MOUNT_##opt
1152 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1153 					 EXT4_MOUNT_##opt)
1154 
1155 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1156 						~EXT4_MOUNT2_##opt
1157 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1158 						EXT4_MOUNT2_##opt
1159 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1160 					 EXT4_MOUNT2_##opt)
1161 
1162 #define ext4_test_and_set_bit		__test_and_set_bit_le
1163 #define ext4_set_bit			__set_bit_le
1164 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1165 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1166 #define ext4_clear_bit			__clear_bit_le
1167 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1168 #define ext4_test_bit			test_bit_le
1169 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1170 #define ext4_find_next_bit		find_next_bit_le
1171 
1172 extern void ext4_set_bits(void *bm, int cur, int len);
1173 
1174 /*
1175  * Maximal mount counts between two filesystem checks
1176  */
1177 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1178 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1179 
1180 /*
1181  * Behaviour when detecting errors
1182  */
1183 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1184 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1185 #define EXT4_ERRORS_PANIC		3	/* Panic */
1186 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1187 
1188 /* Metadata checksum algorithm codes */
1189 #define EXT4_CRC32C_CHKSUM		1
1190 
1191 /*
1192  * Structure of the super block
1193  */
1194 struct ext4_super_block {
1195 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1196 	__le32	s_blocks_count_lo;	/* Blocks count */
1197 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1198 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1199 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1200 	__le32	s_first_data_block;	/* First Data Block */
1201 	__le32	s_log_block_size;	/* Block size */
1202 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1203 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1204 	__le32	s_clusters_per_group;	/* # Clusters per group */
1205 	__le32	s_inodes_per_group;	/* # Inodes per group */
1206 	__le32	s_mtime;		/* Mount time */
1207 /*30*/	__le32	s_wtime;		/* Write time */
1208 	__le16	s_mnt_count;		/* Mount count */
1209 	__le16	s_max_mnt_count;	/* Maximal mount count */
1210 	__le16	s_magic;		/* Magic signature */
1211 	__le16	s_state;		/* File system state */
1212 	__le16	s_errors;		/* Behaviour when detecting errors */
1213 	__le16	s_minor_rev_level;	/* minor revision level */
1214 /*40*/	__le32	s_lastcheck;		/* time of last check */
1215 	__le32	s_checkinterval;	/* max. time between checks */
1216 	__le32	s_creator_os;		/* OS */
1217 	__le32	s_rev_level;		/* Revision level */
1218 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1219 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1220 	/*
1221 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1222 	 *
1223 	 * Note: the difference between the compatible feature set and
1224 	 * the incompatible feature set is that if there is a bit set
1225 	 * in the incompatible feature set that the kernel doesn't
1226 	 * know about, it should refuse to mount the filesystem.
1227 	 *
1228 	 * e2fsck's requirements are more strict; if it doesn't know
1229 	 * about a feature in either the compatible or incompatible
1230 	 * feature set, it must abort and not try to meddle with
1231 	 * things it doesn't understand...
1232 	 */
1233 	__le32	s_first_ino;		/* First non-reserved inode */
1234 	__le16  s_inode_size;		/* size of inode structure */
1235 	__le16	s_block_group_nr;	/* block group # of this superblock */
1236 	__le32	s_feature_compat;	/* compatible feature set */
1237 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1238 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1239 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1240 /*78*/	char	s_volume_name[16];	/* volume name */
1241 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
1242 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1243 	/*
1244 	 * Performance hints.  Directory preallocation should only
1245 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1246 	 */
1247 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1248 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1249 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1250 	/*
1251 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1252 	 */
1253 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1254 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1255 	__le32	s_journal_dev;		/* device number of journal file */
1256 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1257 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1258 	__u8	s_def_hash_version;	/* Default hash version to use */
1259 	__u8	s_jnl_backup_type;
1260 	__le16  s_desc_size;		/* size of group descriptor */
1261 /*100*/	__le32	s_default_mount_opts;
1262 	__le32	s_first_meta_bg;	/* First metablock block group */
1263 	__le32	s_mkfs_time;		/* When the filesystem was created */
1264 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1265 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1266 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1267 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1268 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1269 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1270 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1271 	__le32	s_flags;		/* Miscellaneous flags */
1272 	__le16  s_raid_stride;		/* RAID stride */
1273 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1274 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1275 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1276 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1277 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1278 	__u8	s_encryption_level;	/* versioning level for encryption */
1279 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1280 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1281 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1282 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1283 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1284 					      snapshot's future use */
1285 	__le32	s_snapshot_list;	/* inode number of the head of the
1286 					   on-disk snapshot list */
1287 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1288 	__le32	s_error_count;		/* number of fs errors */
1289 	__le32	s_first_error_time;	/* first time an error happened */
1290 	__le32	s_first_error_ino;	/* inode involved in first error */
1291 	__le64	s_first_error_block;	/* block involved of first error */
1292 	__u8	s_first_error_func[32] __nonstring;	/* function where the error happened */
1293 	__le32	s_first_error_line;	/* line number where error happened */
1294 	__le32	s_last_error_time;	/* most recent time of an error */
1295 	__le32	s_last_error_ino;	/* inode involved in last error */
1296 	__le32	s_last_error_line;	/* line number where error happened */
1297 	__le64	s_last_error_block;	/* block involved of last error */
1298 	__u8	s_last_error_func[32] __nonstring;	/* function where the error happened */
1299 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1300 	__u8	s_mount_opts[64];
1301 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1302 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1303 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1304 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1305 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1306 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1307 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1308 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1309 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1310 	__u8	s_wtime_hi;
1311 	__u8	s_mtime_hi;
1312 	__u8	s_mkfs_time_hi;
1313 	__u8	s_lastcheck_hi;
1314 	__u8	s_first_error_time_hi;
1315 	__u8	s_last_error_time_hi;
1316 	__u8	s_pad[2];
1317 	__le32	s_reserved[96];		/* Padding to the end of the block */
1318 	__le32	s_checksum;		/* crc32c(superblock) */
1319 };
1320 
1321 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1322 
1323 #ifdef __KERNEL__
1324 
1325 /*
1326  * run-time mount flags
1327  */
1328 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1329 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1330 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1331 
1332 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1333 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1334 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1335 #else
1336 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1337 #endif
1338 
1339 /* Number of quota types we support */
1340 #define EXT4_MAXQUOTAS 3
1341 
1342 /*
1343  * fourth extended-fs super-block data in memory
1344  */
1345 struct ext4_sb_info {
1346 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1347 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1348 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1349 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1350 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1351 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1352 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1353 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1354 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1355 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1356 	unsigned long s_overhead;  /* # of fs overhead clusters */
1357 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1358 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1359 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1360 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1361 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1362 	struct buffer_head **s_group_desc;
1363 	unsigned int s_mount_opt;
1364 	unsigned int s_mount_opt2;
1365 	unsigned int s_mount_flags;
1366 	unsigned int s_def_mount_opt;
1367 	ext4_fsblk_t s_sb_block;
1368 	atomic64_t s_resv_clusters;
1369 	kuid_t s_resuid;
1370 	kgid_t s_resgid;
1371 	unsigned short s_mount_state;
1372 	unsigned short s_pad;
1373 	int s_addr_per_block_bits;
1374 	int s_desc_per_block_bits;
1375 	int s_inode_size;
1376 	int s_first_ino;
1377 	unsigned int s_inode_readahead_blks;
1378 	unsigned int s_inode_goal;
1379 	u32 s_hash_seed[4];
1380 	int s_def_hash_version;
1381 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1382 	struct percpu_counter s_freeclusters_counter;
1383 	struct percpu_counter s_freeinodes_counter;
1384 	struct percpu_counter s_dirs_counter;
1385 	struct percpu_counter s_dirtyclusters_counter;
1386 	struct blockgroup_lock *s_blockgroup_lock;
1387 	struct proc_dir_entry *s_proc;
1388 	struct kobject s_kobj;
1389 	struct completion s_kobj_unregister;
1390 	struct super_block *s_sb;
1391 
1392 	/* Journaling */
1393 	struct journal_s *s_journal;
1394 	struct list_head s_orphan;
1395 	struct mutex s_orphan_lock;
1396 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1397 	unsigned long s_commit_interval;
1398 	u32 s_max_batch_time;
1399 	u32 s_min_batch_time;
1400 	struct block_device *journal_bdev;
1401 #ifdef CONFIG_QUOTA
1402 	/* Names of quota files with journalled quota */
1403 	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1404 	int s_jquota_fmt;			/* Format of quota to use */
1405 #endif
1406 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1407 	struct rb_root system_blks;
1408 
1409 #ifdef EXTENTS_STATS
1410 	/* ext4 extents stats */
1411 	unsigned long s_ext_min;
1412 	unsigned long s_ext_max;
1413 	unsigned long s_depth_max;
1414 	spinlock_t s_ext_stats_lock;
1415 	unsigned long s_ext_blocks;
1416 	unsigned long s_ext_extents;
1417 #endif
1418 
1419 	/* for buddy allocator */
1420 	struct ext4_group_info ***s_group_info;
1421 	struct inode *s_buddy_cache;
1422 	spinlock_t s_md_lock;
1423 	unsigned short *s_mb_offsets;
1424 	unsigned int *s_mb_maxs;
1425 	unsigned int s_group_info_size;
1426 	unsigned int s_mb_free_pending;
1427 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1428 						   after commit completed */
1429 
1430 	/* tunables */
1431 	unsigned long s_stripe;
1432 	unsigned int s_mb_stream_request;
1433 	unsigned int s_mb_max_to_scan;
1434 	unsigned int s_mb_min_to_scan;
1435 	unsigned int s_mb_stats;
1436 	unsigned int s_mb_order2_reqs;
1437 	unsigned int s_mb_group_prealloc;
1438 	unsigned int s_max_dir_size_kb;
1439 	/* where last allocation was done - for stream allocation */
1440 	unsigned long s_mb_last_group;
1441 	unsigned long s_mb_last_start;
1442 
1443 	/* stats for buddy allocator */
1444 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1445 	atomic_t s_bal_success;	/* we found long enough chunks */
1446 	atomic_t s_bal_allocated;	/* in blocks */
1447 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1448 	atomic_t s_bal_goals;	/* goal hits */
1449 	atomic_t s_bal_breaks;	/* too long searches */
1450 	atomic_t s_bal_2orders;	/* 2^order hits */
1451 	spinlock_t s_bal_lock;
1452 	unsigned long s_mb_buddies_generated;
1453 	unsigned long long s_mb_generation_time;
1454 	atomic_t s_mb_lost_chunks;
1455 	atomic_t s_mb_preallocated;
1456 	atomic_t s_mb_discarded;
1457 	atomic_t s_lock_busy;
1458 
1459 	/* locality groups */
1460 	struct ext4_locality_group __percpu *s_locality_groups;
1461 
1462 	/* for write statistics */
1463 	unsigned long s_sectors_written_start;
1464 	u64 s_kbytes_written;
1465 
1466 	/* the size of zero-out chunk */
1467 	unsigned int s_extent_max_zeroout_kb;
1468 
1469 	unsigned int s_log_groups_per_flex;
1470 	struct flex_groups *s_flex_groups;
1471 	ext4_group_t s_flex_groups_allocated;
1472 
1473 	/* workqueue for reserved extent conversions (buffered io) */
1474 	struct workqueue_struct *rsv_conversion_wq;
1475 
1476 	/* timer for periodic error stats printing */
1477 	struct timer_list s_err_report;
1478 
1479 	/* Lazy inode table initialization info */
1480 	struct ext4_li_request *s_li_request;
1481 	/* Wait multiplier for lazy initialization thread */
1482 	unsigned int s_li_wait_mult;
1483 
1484 	/* Kernel thread for multiple mount protection */
1485 	struct task_struct *s_mmp_tsk;
1486 
1487 	/* record the last minlen when FITRIM is called. */
1488 	atomic_t s_last_trim_minblks;
1489 
1490 	/* Reference to checksum algorithm driver via cryptoapi */
1491 	struct crypto_shash *s_chksum_driver;
1492 
1493 	/* Precomputed FS UUID checksum for seeding other checksums */
1494 	__u32 s_csum_seed;
1495 
1496 	/* Reclaim extents from extent status tree */
1497 	struct shrinker s_es_shrinker;
1498 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1499 	long s_es_nr_inode;
1500 	struct ext4_es_stats s_es_stats;
1501 	struct mb_cache *s_ea_block_cache;
1502 	struct mb_cache *s_ea_inode_cache;
1503 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1504 
1505 	/* Ratelimit ext4 messages. */
1506 	struct ratelimit_state s_err_ratelimit_state;
1507 	struct ratelimit_state s_warning_ratelimit_state;
1508 	struct ratelimit_state s_msg_ratelimit_state;
1509 
1510 	/* Barrier between changing inodes' journal flags and writepages ops. */
1511 	struct percpu_rw_semaphore s_journal_flag_rwsem;
1512 	struct dax_device *s_daxdev;
1513 };
1514 
1515 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1516 {
1517 	return sb->s_fs_info;
1518 }
1519 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1520 {
1521 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1522 }
1523 
1524 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1525 {
1526 	return ino == EXT4_ROOT_INO ||
1527 		(ino >= EXT4_FIRST_INO(sb) &&
1528 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1529 }
1530 
1531 /*
1532  * Inode dynamic state flags
1533  */
1534 enum {
1535 	EXT4_STATE_JDATA,		/* journaled data exists */
1536 	EXT4_STATE_NEW,			/* inode is newly created */
1537 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1538 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1539 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1540 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1541 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1542 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1543 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1544 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1545 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1546 };
1547 
1548 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1549 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1550 {									\
1551 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1552 }									\
1553 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1554 {									\
1555 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1556 }									\
1557 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1558 {									\
1559 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1560 }
1561 
1562 /* Add these declarations here only so that these functions can be
1563  * found by name.  Otherwise, they are very hard to locate. */
1564 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1565 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1566 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1567 EXT4_INODE_BIT_FNS(flag, flags, 0)
1568 
1569 /* Add these declarations here only so that these functions can be
1570  * found by name.  Otherwise, they are very hard to locate. */
1571 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1572 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1573 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1574 #if (BITS_PER_LONG < 64)
1575 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1576 
1577 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1578 {
1579 	(ei)->i_state_flags = 0;
1580 }
1581 #else
1582 EXT4_INODE_BIT_FNS(state, flags, 32)
1583 
1584 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1585 {
1586 	/* We depend on the fact that callers will set i_flags */
1587 }
1588 #endif
1589 #else
1590 /* Assume that user mode programs are passing in an ext4fs superblock, not
1591  * a kernel struct super_block.  This will allow us to call the feature-test
1592  * macros from user land. */
1593 #define EXT4_SB(sb)	(sb)
1594 #endif
1595 
1596 /*
1597  * Returns true if the inode is inode is encrypted
1598  */
1599 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1600 
1601 /*
1602  * Codes for operating systems
1603  */
1604 #define EXT4_OS_LINUX		0
1605 #define EXT4_OS_HURD		1
1606 #define EXT4_OS_MASIX		2
1607 #define EXT4_OS_FREEBSD		3
1608 #define EXT4_OS_LITES		4
1609 
1610 /*
1611  * Revision levels
1612  */
1613 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1614 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1615 
1616 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1617 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1618 
1619 #define EXT4_GOOD_OLD_INODE_SIZE 128
1620 
1621 /*
1622  * Feature set definitions
1623  */
1624 
1625 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1626 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1627 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1628 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1629 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1630 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1631 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1632 
1633 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1634 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1635 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1636 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1637 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1638 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1639 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1640 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1641 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1642 /*
1643  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1644  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1645  * all other data structures' checksums.  However, the METADATA_CSUM and
1646  * GDT_CSUM bits are mutually exclusive.
1647  */
1648 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1649 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1650 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1651 
1652 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1653 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1654 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1655 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1656 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1657 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1658 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1659 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1660 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1661 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1662 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1663 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1664 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1665 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1666 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1667 
1668 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1669 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1670 { \
1671 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1672 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1673 } \
1674 static inline void ext4_set_feature_##name(struct super_block *sb) \
1675 { \
1676 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1677 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1678 } \
1679 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1680 { \
1681 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1682 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1683 }
1684 
1685 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1686 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1687 { \
1688 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1689 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1690 } \
1691 static inline void ext4_set_feature_##name(struct super_block *sb) \
1692 { \
1693 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1694 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1695 } \
1696 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1697 { \
1698 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1699 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1700 }
1701 
1702 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1703 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1704 { \
1705 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1706 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1707 } \
1708 static inline void ext4_set_feature_##name(struct super_block *sb) \
1709 { \
1710 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
1711 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1712 } \
1713 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1714 { \
1715 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1716 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1717 }
1718 
1719 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1720 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1721 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1722 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1723 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1724 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1725 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1726 
1727 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1728 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1729 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1730 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1731 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1732 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1733 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1734 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1735 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1736 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1737 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1738 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1739 
1740 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1741 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
1742 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
1743 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
1744 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
1745 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
1746 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
1747 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
1748 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
1749 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
1750 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
1751 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
1752 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
1753 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
1754 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
1755 
1756 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1757 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1758 					 EXT4_FEATURE_INCOMPAT_META_BG)
1759 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1760 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1761 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1762 
1763 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1764 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1765 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1766 					 EXT4_FEATURE_INCOMPAT_META_BG)
1767 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1768 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1769 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1770 
1771 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1772 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1773 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1774 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1775 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1776 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1777 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1778 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
1779 					 EXT4_FEATURE_INCOMPAT_MMP | \
1780 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1781 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1782 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
1783 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
1784 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1785 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1786 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1787 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1788 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1789 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1790 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1791 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1792 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1793 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
1794 					 EXT4_FEATURE_RO_COMPAT_PROJECT)
1795 
1796 #define EXTN_FEATURE_FUNCS(ver) \
1797 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1798 { \
1799 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1800 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1801 } \
1802 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1803 { \
1804 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1805 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1806 } \
1807 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1808 { \
1809 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1810 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1811 }
1812 
1813 EXTN_FEATURE_FUNCS(2)
1814 EXTN_FEATURE_FUNCS(3)
1815 EXTN_FEATURE_FUNCS(4)
1816 
1817 static inline bool ext4_has_compat_features(struct super_block *sb)
1818 {
1819 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1820 }
1821 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1822 {
1823 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1824 }
1825 static inline bool ext4_has_incompat_features(struct super_block *sb)
1826 {
1827 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
1828 }
1829 
1830 /*
1831  * Superblock flags
1832  */
1833 #define EXT4_FLAGS_RESIZING	0
1834 #define EXT4_FLAGS_SHUTDOWN	1
1835 
1836 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
1837 {
1838 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
1839 }
1840 
1841 
1842 /*
1843  * Default values for user and/or group using reserved blocks
1844  */
1845 #define	EXT4_DEF_RESUID		0
1846 #define	EXT4_DEF_RESGID		0
1847 
1848 /*
1849  * Default project ID
1850  */
1851 #define	EXT4_DEF_PROJID		0
1852 
1853 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1854 
1855 /*
1856  * Default mount options
1857  */
1858 #define EXT4_DEFM_DEBUG		0x0001
1859 #define EXT4_DEFM_BSDGROUPS	0x0002
1860 #define EXT4_DEFM_XATTR_USER	0x0004
1861 #define EXT4_DEFM_ACL		0x0008
1862 #define EXT4_DEFM_UID16		0x0010
1863 #define EXT4_DEFM_JMODE		0x0060
1864 #define EXT4_DEFM_JMODE_DATA	0x0020
1865 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1866 #define EXT4_DEFM_JMODE_WBACK	0x0060
1867 #define EXT4_DEFM_NOBARRIER	0x0100
1868 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1869 #define EXT4_DEFM_DISCARD	0x0400
1870 #define EXT4_DEFM_NODELALLOC	0x0800
1871 
1872 /*
1873  * Default journal batch times
1874  */
1875 #define EXT4_DEF_MIN_BATCH_TIME	0
1876 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1877 
1878 /*
1879  * Minimum number of groups in a flexgroup before we separate out
1880  * directories into the first block group of a flexgroup
1881  */
1882 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1883 
1884 /*
1885  * Structure of a directory entry
1886  */
1887 #define EXT4_NAME_LEN 255
1888 
1889 struct ext4_dir_entry {
1890 	__le32	inode;			/* Inode number */
1891 	__le16	rec_len;		/* Directory entry length */
1892 	__le16	name_len;		/* Name length */
1893 	char	name[EXT4_NAME_LEN];	/* File name */
1894 };
1895 
1896 /*
1897  * The new version of the directory entry.  Since EXT4 structures are
1898  * stored in intel byte order, and the name_len field could never be
1899  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1900  * file_type field.
1901  */
1902 struct ext4_dir_entry_2 {
1903 	__le32	inode;			/* Inode number */
1904 	__le16	rec_len;		/* Directory entry length */
1905 	__u8	name_len;		/* Name length */
1906 	__u8	file_type;
1907 	char	name[EXT4_NAME_LEN];	/* File name */
1908 };
1909 
1910 /*
1911  * This is a bogus directory entry at the end of each leaf block that
1912  * records checksums.
1913  */
1914 struct ext4_dir_entry_tail {
1915 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1916 	__le16	det_rec_len;		/* 12 */
1917 	__u8	det_reserved_zero2;	/* Zero name length */
1918 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1919 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1920 };
1921 
1922 #define EXT4_DIRENT_TAIL(block, blocksize) \
1923 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1924 					((blocksize) - \
1925 					 sizeof(struct ext4_dir_entry_tail))))
1926 
1927 /*
1928  * Ext4 directory file types.  Only the low 3 bits are used.  The
1929  * other bits are reserved for now.
1930  */
1931 #define EXT4_FT_UNKNOWN		0
1932 #define EXT4_FT_REG_FILE	1
1933 #define EXT4_FT_DIR		2
1934 #define EXT4_FT_CHRDEV		3
1935 #define EXT4_FT_BLKDEV		4
1936 #define EXT4_FT_FIFO		5
1937 #define EXT4_FT_SOCK		6
1938 #define EXT4_FT_SYMLINK		7
1939 
1940 #define EXT4_FT_MAX		8
1941 
1942 #define EXT4_FT_DIR_CSUM	0xDE
1943 
1944 /*
1945  * EXT4_DIR_PAD defines the directory entries boundaries
1946  *
1947  * NOTE: It must be a multiple of 4
1948  */
1949 #define EXT4_DIR_PAD			4
1950 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1951 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1952 					 ~EXT4_DIR_ROUND)
1953 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1954 
1955 /*
1956  * If we ever get support for fs block sizes > page_size, we'll need
1957  * to remove the #if statements in the next two functions...
1958  */
1959 static inline unsigned int
1960 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1961 {
1962 	unsigned len = le16_to_cpu(dlen);
1963 
1964 #if (PAGE_SIZE >= 65536)
1965 	if (len == EXT4_MAX_REC_LEN || len == 0)
1966 		return blocksize;
1967 	return (len & 65532) | ((len & 3) << 16);
1968 #else
1969 	return len;
1970 #endif
1971 }
1972 
1973 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1974 {
1975 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1976 		BUG();
1977 #if (PAGE_SIZE >= 65536)
1978 	if (len < 65536)
1979 		return cpu_to_le16(len);
1980 	if (len == blocksize) {
1981 		if (blocksize == 65536)
1982 			return cpu_to_le16(EXT4_MAX_REC_LEN);
1983 		else
1984 			return cpu_to_le16(0);
1985 	}
1986 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1987 #else
1988 	return cpu_to_le16(len);
1989 #endif
1990 }
1991 
1992 /*
1993  * Hash Tree Directory indexing
1994  * (c) Daniel Phillips, 2001
1995  */
1996 
1997 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
1998 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1999 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2000 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2001 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2002 
2003 /* Legal values for the dx_root hash_version field: */
2004 
2005 #define DX_HASH_LEGACY			0
2006 #define DX_HASH_HALF_MD4		1
2007 #define DX_HASH_TEA			2
2008 #define DX_HASH_LEGACY_UNSIGNED		3
2009 #define DX_HASH_HALF_MD4_UNSIGNED	4
2010 #define DX_HASH_TEA_UNSIGNED		5
2011 
2012 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2013 			      const void *address, unsigned int length)
2014 {
2015 	struct {
2016 		struct shash_desc shash;
2017 		char ctx[4];
2018 	} desc;
2019 
2020 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2021 
2022 	desc.shash.tfm = sbi->s_chksum_driver;
2023 	desc.shash.flags = 0;
2024 	*(u32 *)desc.ctx = crc;
2025 
2026 	BUG_ON(crypto_shash_update(&desc.shash, address, length));
2027 
2028 	return *(u32 *)desc.ctx;
2029 }
2030 
2031 #ifdef __KERNEL__
2032 
2033 /* hash info structure used by the directory hash */
2034 struct dx_hash_info
2035 {
2036 	u32		hash;
2037 	u32		minor_hash;
2038 	int		hash_version;
2039 	u32		*seed;
2040 };
2041 
2042 
2043 /* 32 and 64 bit signed EOF for dx directories */
2044 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2045 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2046 
2047 
2048 /*
2049  * Control parameters used by ext4_htree_next_block
2050  */
2051 #define HASH_NB_ALWAYS		1
2052 
2053 struct ext4_filename {
2054 	const struct qstr *usr_fname;
2055 	struct fscrypt_str disk_name;
2056 	struct dx_hash_info hinfo;
2057 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2058 	struct fscrypt_str crypto_buf;
2059 #endif
2060 };
2061 
2062 #define fname_name(p) ((p)->disk_name.name)
2063 #define fname_len(p)  ((p)->disk_name.len)
2064 
2065 /*
2066  * Describe an inode's exact location on disk and in memory
2067  */
2068 struct ext4_iloc
2069 {
2070 	struct buffer_head *bh;
2071 	unsigned long offset;
2072 	ext4_group_t block_group;
2073 };
2074 
2075 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2076 {
2077 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2078 }
2079 
2080 static inline bool ext4_is_quota_file(struct inode *inode)
2081 {
2082 	return IS_NOQUOTA(inode) &&
2083 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2084 }
2085 
2086 /*
2087  * This structure is stuffed into the struct file's private_data field
2088  * for directories.  It is where we put information so that we can do
2089  * readdir operations in hash tree order.
2090  */
2091 struct dir_private_info {
2092 	struct rb_root	root;
2093 	struct rb_node	*curr_node;
2094 	struct fname	*extra_fname;
2095 	loff_t		last_pos;
2096 	__u32		curr_hash;
2097 	__u32		curr_minor_hash;
2098 	__u32		next_hash;
2099 };
2100 
2101 /* calculate the first block number of the group */
2102 static inline ext4_fsblk_t
2103 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2104 {
2105 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2106 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2107 }
2108 
2109 /*
2110  * Special error return code only used by dx_probe() and its callers.
2111  */
2112 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2113 
2114 /* htree levels for ext4 */
2115 #define	EXT4_HTREE_LEVEL_COMPAT	2
2116 #define	EXT4_HTREE_LEVEL	3
2117 
2118 static inline int ext4_dir_htree_level(struct super_block *sb)
2119 {
2120 	return ext4_has_feature_largedir(sb) ?
2121 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2122 }
2123 
2124 /*
2125  * Timeout and state flag for lazy initialization inode thread.
2126  */
2127 #define EXT4_DEF_LI_WAIT_MULT			10
2128 #define EXT4_DEF_LI_MAX_START_DELAY		5
2129 #define EXT4_LAZYINIT_QUIT			0x0001
2130 #define EXT4_LAZYINIT_RUNNING			0x0002
2131 
2132 /*
2133  * Lazy inode table initialization info
2134  */
2135 struct ext4_lazy_init {
2136 	unsigned long		li_state;
2137 	struct list_head	li_request_list;
2138 	struct mutex		li_list_mtx;
2139 };
2140 
2141 struct ext4_li_request {
2142 	struct super_block	*lr_super;
2143 	struct ext4_sb_info	*lr_sbi;
2144 	ext4_group_t		lr_next_group;
2145 	struct list_head	lr_request;
2146 	unsigned long		lr_next_sched;
2147 	unsigned long		lr_timeout;
2148 };
2149 
2150 struct ext4_features {
2151 	struct kobject f_kobj;
2152 	struct completion f_kobj_unregister;
2153 };
2154 
2155 /*
2156  * This structure will be used for multiple mount protection. It will be
2157  * written into the block number saved in the s_mmp_block field in the
2158  * superblock. Programs that check MMP should assume that if
2159  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2160  * to use the filesystem, regardless of how old the timestamp is.
2161  */
2162 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2163 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2164 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2165 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2166 
2167 struct mmp_struct {
2168 	__le32	mmp_magic;		/* Magic number for MMP */
2169 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2170 
2171 	/*
2172 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2173 	 * purposes and do not affect the correctness of the algorithm
2174 	 */
2175 	__le64	mmp_time;		/* Time last updated */
2176 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2177 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2178 
2179 	/*
2180 	 * mmp_check_interval is used to verify if the MMP block has been
2181 	 * updated on the block device. The value is updated based on the
2182 	 * maximum time to write the MMP block during an update cycle.
2183 	 */
2184 	__le16	mmp_check_interval;
2185 
2186 	__le16	mmp_pad1;
2187 	__le32	mmp_pad2[226];
2188 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2189 };
2190 
2191 /* arguments passed to the mmp thread */
2192 struct mmpd_data {
2193 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2194 	struct super_block *sb;  /* super block of the fs */
2195 };
2196 
2197 /*
2198  * Check interval multiplier
2199  * The MMP block is written every update interval and initially checked every
2200  * update interval x the multiplier (the value is then adapted based on the
2201  * write latency). The reason is that writes can be delayed under load and we
2202  * don't want readers to incorrectly assume that the filesystem is no longer
2203  * in use.
2204  */
2205 #define EXT4_MMP_CHECK_MULT		2UL
2206 
2207 /*
2208  * Minimum interval for MMP checking in seconds.
2209  */
2210 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2211 
2212 /*
2213  * Maximum interval for MMP checking in seconds.
2214  */
2215 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2216 
2217 /*
2218  * Function prototypes
2219  */
2220 
2221 /*
2222  * Ok, these declarations are also in <linux/kernel.h> but none of the
2223  * ext4 source programs needs to include it so they are duplicated here.
2224  */
2225 # define NORET_TYPE	/**/
2226 # define ATTRIB_NORET	__attribute__((noreturn))
2227 # define NORET_AND	noreturn,
2228 
2229 /* bitmap.c */
2230 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2231 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2232 				struct ext4_group_desc *gdp,
2233 				struct buffer_head *bh, int sz);
2234 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2235 				  struct ext4_group_desc *gdp,
2236 				  struct buffer_head *bh, int sz);
2237 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2238 				struct ext4_group_desc *gdp,
2239 				struct buffer_head *bh);
2240 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2241 				  struct ext4_group_desc *gdp,
2242 				  struct buffer_head *bh);
2243 
2244 /* balloc.c */
2245 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2246 					 ext4_fsblk_t blocknr,
2247 					 ext4_group_t *blockgrpp,
2248 					 ext4_grpblk_t *offsetp);
2249 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2250 					  ext4_fsblk_t block);
2251 
2252 extern unsigned int ext4_block_group(struct super_block *sb,
2253 			ext4_fsblk_t blocknr);
2254 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2255 			ext4_fsblk_t blocknr);
2256 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2257 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2258 			ext4_group_t group);
2259 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2260 					 ext4_fsblk_t goal,
2261 					 unsigned int flags,
2262 					 unsigned long *count,
2263 					 int *errp);
2264 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2265 				    s64 nclusters, unsigned int flags);
2266 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2267 extern void ext4_check_blocks_bitmap(struct super_block *);
2268 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2269 						    ext4_group_t block_group,
2270 						    struct buffer_head ** bh);
2271 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2272 
2273 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2274 						ext4_group_t block_group);
2275 extern int ext4_wait_block_bitmap(struct super_block *sb,
2276 				  ext4_group_t block_group,
2277 				  struct buffer_head *bh);
2278 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2279 						  ext4_group_t block_group);
2280 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2281 					      ext4_group_t block_group,
2282 					      struct ext4_group_desc *gdp);
2283 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2284 
2285 static inline bool ext4_encrypted_inode(struct inode *inode)
2286 {
2287 	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
2288 }
2289 
2290 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2291 static inline int ext4_fname_setup_filename(struct inode *dir,
2292 			const struct qstr *iname,
2293 			int lookup, struct ext4_filename *fname)
2294 {
2295 	struct fscrypt_name name;
2296 	int err;
2297 
2298 	memset(fname, 0, sizeof(struct ext4_filename));
2299 
2300 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2301 
2302 	fname->usr_fname = name.usr_fname;
2303 	fname->disk_name = name.disk_name;
2304 	fname->hinfo.hash = name.hash;
2305 	fname->hinfo.minor_hash = name.minor_hash;
2306 	fname->crypto_buf = name.crypto_buf;
2307 	return err;
2308 }
2309 
2310 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2311 {
2312 	struct fscrypt_name name;
2313 
2314 	name.crypto_buf = fname->crypto_buf;
2315 	fscrypt_free_filename(&name);
2316 
2317 	fname->crypto_buf.name = NULL;
2318 	fname->usr_fname = NULL;
2319 	fname->disk_name.name = NULL;
2320 }
2321 #else
2322 static inline int ext4_fname_setup_filename(struct inode *dir,
2323 		const struct qstr *iname,
2324 		int lookup, struct ext4_filename *fname)
2325 {
2326 	fname->usr_fname = iname;
2327 	fname->disk_name.name = (unsigned char *) iname->name;
2328 	fname->disk_name.len = iname->len;
2329 	return 0;
2330 }
2331 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2332 
2333 #endif
2334 
2335 /* dir.c */
2336 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2337 				  struct file *,
2338 				  struct ext4_dir_entry_2 *,
2339 				  struct buffer_head *, char *, int,
2340 				  unsigned int);
2341 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2342 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2343 					(de), (bh), (buf), (size), (offset)))
2344 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2345 				__u32 minor_hash,
2346 				struct ext4_dir_entry_2 *dirent,
2347 				struct fscrypt_str *ent_name);
2348 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2349 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2350 			     struct buffer_head *bh,
2351 			     void *buf, int buf_size,
2352 			     struct ext4_filename *fname,
2353 			     struct ext4_dir_entry_2 **dest_de);
2354 void ext4_insert_dentry(struct inode *inode,
2355 			struct ext4_dir_entry_2 *de,
2356 			int buf_size,
2357 			struct ext4_filename *fname);
2358 static inline void ext4_update_dx_flag(struct inode *inode)
2359 {
2360 	if (!ext4_has_feature_dir_index(inode->i_sb))
2361 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2362 }
2363 static const unsigned char ext4_filetype_table[] = {
2364 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2365 };
2366 
2367 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2368 {
2369 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2370 		return DT_UNKNOWN;
2371 
2372 	return ext4_filetype_table[filetype];
2373 }
2374 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2375 			     void *buf, int buf_size);
2376 
2377 /* fsync.c */
2378 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2379 
2380 /* hash.c */
2381 extern int ext4fs_dirhash(const char *name, int len, struct
2382 			  dx_hash_info *hinfo);
2383 
2384 /* ialloc.c */
2385 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2386 				      const struct qstr *qstr, __u32 goal,
2387 				      uid_t *owner, __u32 i_flags,
2388 				      int handle_type, unsigned int line_no,
2389 				      int nblocks);
2390 
2391 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2392 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2393 			 i_flags, 0, 0, 0)
2394 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2395 				    type, nblocks)		    \
2396 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2397 			 0, (type), __LINE__, (nblocks))
2398 
2399 
2400 extern void ext4_free_inode(handle_t *, struct inode *);
2401 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2402 extern unsigned long ext4_count_free_inodes(struct super_block *);
2403 extern unsigned long ext4_count_dirs(struct super_block *);
2404 extern void ext4_check_inodes_bitmap(struct super_block *);
2405 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2406 extern int ext4_init_inode_table(struct super_block *sb,
2407 				 ext4_group_t group, int barrier);
2408 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2409 
2410 /* mballoc.c */
2411 extern const struct seq_operations ext4_mb_seq_groups_ops;
2412 extern long ext4_mb_stats;
2413 extern long ext4_mb_max_to_scan;
2414 extern int ext4_mb_init(struct super_block *);
2415 extern int ext4_mb_release(struct super_block *);
2416 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2417 				struct ext4_allocation_request *, int *);
2418 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2419 extern void ext4_discard_preallocations(struct inode *);
2420 extern int __init ext4_init_mballoc(void);
2421 extern void ext4_exit_mballoc(void);
2422 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2423 			     struct buffer_head *bh, ext4_fsblk_t block,
2424 			     unsigned long count, int flags);
2425 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2426 				   ext4_group_t ngroups);
2427 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2428 		ext4_group_t i, struct ext4_group_desc *desc);
2429 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2430 				ext4_fsblk_t block, unsigned long count);
2431 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2432 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2433 
2434 /* inode.c */
2435 int ext4_inode_is_fast_symlink(struct inode *inode);
2436 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2437 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2438 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2439 		     bool wait, struct buffer_head **bhs);
2440 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2441 			     struct buffer_head *bh_result, int create);
2442 int ext4_get_block(struct inode *inode, sector_t iblock,
2443 		   struct buffer_head *bh_result, int create);
2444 int ext4_dio_get_block(struct inode *inode, sector_t iblock,
2445 		       struct buffer_head *bh_result, int create);
2446 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2447 			   struct buffer_head *bh, int create);
2448 int ext4_walk_page_buffers(handle_t *handle,
2449 			   struct buffer_head *head,
2450 			   unsigned from,
2451 			   unsigned to,
2452 			   int *partial,
2453 			   int (*fn)(handle_t *handle,
2454 				     struct buffer_head *bh));
2455 int do_journal_get_write_access(handle_t *handle,
2456 				struct buffer_head *bh);
2457 #define FALL_BACK_TO_NONDELALLOC 1
2458 #define CONVERT_INLINE_DATA	 2
2459 
2460 typedef enum {
2461 	EXT4_IGET_NORMAL =	0,
2462 	EXT4_IGET_SPECIAL =	0x0001, /* OK to iget a system inode */
2463 	EXT4_IGET_HANDLE = 	0x0002	/* Inode # is from a handle */
2464 } ext4_iget_flags;
2465 
2466 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2467 				 ext4_iget_flags flags, const char *function,
2468 				 unsigned int line);
2469 
2470 #define ext4_iget(sb, ino, flags) \
2471 	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2472 
2473 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2474 extern int  ext4_setattr(struct dentry *, struct iattr *);
2475 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2476 extern void ext4_evict_inode(struct inode *);
2477 extern void ext4_clear_inode(struct inode *);
2478 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2479 extern int  ext4_sync_inode(handle_t *, struct inode *);
2480 extern void ext4_dirty_inode(struct inode *, int);
2481 extern int ext4_change_inode_journal_flag(struct inode *, int);
2482 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2483 extern int ext4_inode_attach_jinode(struct inode *inode);
2484 extern int ext4_can_truncate(struct inode *inode);
2485 extern int ext4_truncate(struct inode *);
2486 extern int ext4_break_layouts(struct inode *);
2487 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2488 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2489 extern void ext4_set_inode_flags(struct inode *);
2490 extern int ext4_alloc_da_blocks(struct inode *inode);
2491 extern void ext4_set_aops(struct inode *inode);
2492 extern int ext4_writepage_trans_blocks(struct inode *);
2493 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2494 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2495 			     loff_t lstart, loff_t lend);
2496 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
2497 extern vm_fault_t ext4_filemap_fault(struct vm_fault *vmf);
2498 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2499 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2500 extern void ext4_da_release_space(struct inode *inode, int to_free);
2501 extern void ext4_da_update_reserve_space(struct inode *inode,
2502 					int used, int quota_claim);
2503 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2504 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2505 
2506 /* indirect.c */
2507 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2508 				struct ext4_map_blocks *map, int flags);
2509 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2510 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2511 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2512 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2513 				 ext4_lblk_t start, ext4_lblk_t end);
2514 
2515 /* ioctl.c */
2516 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2517 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2518 
2519 /* migrate.c */
2520 extern int ext4_ext_migrate(struct inode *);
2521 extern int ext4_ind_migrate(struct inode *inode);
2522 
2523 /* namei.c */
2524 extern int ext4_dirent_csum_verify(struct inode *inode,
2525 				   struct ext4_dir_entry *dirent);
2526 extern int ext4_orphan_add(handle_t *, struct inode *);
2527 extern int ext4_orphan_del(handle_t *, struct inode *);
2528 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2529 				__u32 start_minor_hash, __u32 *next_hash);
2530 extern int ext4_search_dir(struct buffer_head *bh,
2531 			   char *search_buf,
2532 			   int buf_size,
2533 			   struct inode *dir,
2534 			   struct ext4_filename *fname,
2535 			   unsigned int offset,
2536 			   struct ext4_dir_entry_2 **res_dir);
2537 extern int ext4_generic_delete_entry(handle_t *handle,
2538 				     struct inode *dir,
2539 				     struct ext4_dir_entry_2 *de_del,
2540 				     struct buffer_head *bh,
2541 				     void *entry_buf,
2542 				     int buf_size,
2543 				     int csum_size);
2544 extern bool ext4_empty_dir(struct inode *inode);
2545 
2546 /* resize.c */
2547 extern int ext4_group_add(struct super_block *sb,
2548 				struct ext4_new_group_data *input);
2549 extern int ext4_group_extend(struct super_block *sb,
2550 				struct ext4_super_block *es,
2551 				ext4_fsblk_t n_blocks_count);
2552 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2553 
2554 /* super.c */
2555 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
2556 					 sector_t block, int op_flags);
2557 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2558 extern int ext4_calculate_overhead(struct super_block *sb);
2559 extern void ext4_superblock_csum_set(struct super_block *sb);
2560 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2561 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2562 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2563 				    ext4_group_t ngroup);
2564 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2565 				     char nbuf[16]);
2566 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
2567 					     ext4_group_t block_group,
2568 					     unsigned int flags);
2569 
2570 extern __printf(4, 5)
2571 void __ext4_error(struct super_block *, const char *, unsigned int,
2572 		  const char *, ...);
2573 extern __printf(5, 6)
2574 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2575 		      const char *, ...);
2576 extern __printf(5, 6)
2577 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2578 		     const char *, ...);
2579 extern void __ext4_std_error(struct super_block *, const char *,
2580 			     unsigned int, int);
2581 extern __printf(4, 5)
2582 void __ext4_abort(struct super_block *, const char *, unsigned int,
2583 		  const char *, ...);
2584 extern __printf(4, 5)
2585 void __ext4_warning(struct super_block *, const char *, unsigned int,
2586 		    const char *, ...);
2587 extern __printf(4, 5)
2588 void __ext4_warning_inode(const struct inode *inode, const char *function,
2589 			  unsigned int line, const char *fmt, ...);
2590 extern __printf(3, 4)
2591 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2592 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2593 			   const char *, unsigned int, const char *);
2594 extern __printf(7, 8)
2595 void __ext4_grp_locked_error(const char *, unsigned int,
2596 			     struct super_block *, ext4_group_t,
2597 			     unsigned long, ext4_fsblk_t,
2598 			     const char *, ...);
2599 
2600 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2601 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2602 
2603 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
2604 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2605 
2606 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2607 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2608 
2609 #ifdef CONFIG_PRINTK
2610 
2611 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2612 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2613 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2614 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2615 #define ext4_error(sb, fmt, ...)					\
2616 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2617 #define ext4_abort(sb, fmt, ...)					\
2618 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2619 #define ext4_warning(sb, fmt, ...)					\
2620 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2621 #define ext4_warning_inode(inode, fmt, ...)				\
2622 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2623 #define ext4_msg(sb, level, fmt, ...)				\
2624 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2625 #define dump_mmp_msg(sb, mmp, msg)					\
2626 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2627 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2628 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2629 				fmt, ##__VA_ARGS__)
2630 
2631 #else
2632 
2633 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2634 do {									\
2635 	no_printk(fmt, ##__VA_ARGS__);					\
2636 	__ext4_error_inode(inode, "", 0, block, " ");			\
2637 } while (0)
2638 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2639 do {									\
2640 	no_printk(fmt, ##__VA_ARGS__);					\
2641 	__ext4_error_file(file, "", 0, block, " ");			\
2642 } while (0)
2643 #define ext4_error(sb, fmt, ...)					\
2644 do {									\
2645 	no_printk(fmt, ##__VA_ARGS__);					\
2646 	__ext4_error(sb, "", 0, " ");					\
2647 } while (0)
2648 #define ext4_abort(sb, fmt, ...)					\
2649 do {									\
2650 	no_printk(fmt, ##__VA_ARGS__);					\
2651 	__ext4_abort(sb, "", 0, " ");					\
2652 } while (0)
2653 #define ext4_warning(sb, fmt, ...)					\
2654 do {									\
2655 	no_printk(fmt, ##__VA_ARGS__);					\
2656 	__ext4_warning(sb, "", 0, " ");					\
2657 } while (0)
2658 #define ext4_warning_inode(inode, fmt, ...)				\
2659 do {									\
2660 	no_printk(fmt, ##__VA_ARGS__);					\
2661 	__ext4_warning_inode(inode, "", 0, " ");			\
2662 } while (0)
2663 #define ext4_msg(sb, level, fmt, ...)					\
2664 do {									\
2665 	no_printk(fmt, ##__VA_ARGS__);					\
2666 	__ext4_msg(sb, "", " ");					\
2667 } while (0)
2668 #define dump_mmp_msg(sb, mmp, msg)					\
2669 	__dump_mmp_msg(sb, mmp, "", 0, "")
2670 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2671 do {									\
2672 	no_printk(fmt, ##__VA_ARGS__);				\
2673 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2674 } while (0)
2675 
2676 #endif
2677 
2678 extern void ext4_update_dynamic_rev(struct super_block *sb);
2679 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2680 					__u32 compat);
2681 extern int ext4_update_rocompat_feature(handle_t *handle,
2682 					struct super_block *sb,	__u32 rocompat);
2683 extern int ext4_update_incompat_feature(handle_t *handle,
2684 					struct super_block *sb,	__u32 incompat);
2685 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2686 				      struct ext4_group_desc *bg);
2687 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2688 				      struct ext4_group_desc *bg);
2689 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2690 				     struct ext4_group_desc *bg);
2691 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2692 				      struct ext4_group_desc *bg);
2693 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2694 				 struct ext4_group_desc *bg);
2695 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2696 				struct ext4_group_desc *bg);
2697 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2698 				   struct ext4_group_desc *bg);
2699 extern void ext4_block_bitmap_set(struct super_block *sb,
2700 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2701 extern void ext4_inode_bitmap_set(struct super_block *sb,
2702 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2703 extern void ext4_inode_table_set(struct super_block *sb,
2704 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2705 extern void ext4_free_group_clusters_set(struct super_block *sb,
2706 					 struct ext4_group_desc *bg,
2707 					 __u32 count);
2708 extern void ext4_free_inodes_set(struct super_block *sb,
2709 				struct ext4_group_desc *bg, __u32 count);
2710 extern void ext4_used_dirs_set(struct super_block *sb,
2711 				struct ext4_group_desc *bg, __u32 count);
2712 extern void ext4_itable_unused_set(struct super_block *sb,
2713 				   struct ext4_group_desc *bg, __u32 count);
2714 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2715 				       struct ext4_group_desc *gdp);
2716 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2717 				     struct ext4_group_desc *gdp);
2718 extern int ext4_register_li_request(struct super_block *sb,
2719 				    ext4_group_t first_not_zeroed);
2720 
2721 static inline int ext4_has_metadata_csum(struct super_block *sb)
2722 {
2723 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2724 		     !EXT4_SB(sb)->s_chksum_driver);
2725 
2726 	return ext4_has_feature_metadata_csum(sb) &&
2727 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
2728 }
2729 
2730 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2731 {
2732 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
2733 }
2734 
2735 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2736 {
2737 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2738 		le32_to_cpu(es->s_blocks_count_lo);
2739 }
2740 
2741 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2742 {
2743 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2744 		le32_to_cpu(es->s_r_blocks_count_lo);
2745 }
2746 
2747 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2748 {
2749 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2750 		le32_to_cpu(es->s_free_blocks_count_lo);
2751 }
2752 
2753 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2754 					 ext4_fsblk_t blk)
2755 {
2756 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2757 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2758 }
2759 
2760 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2761 					      ext4_fsblk_t blk)
2762 {
2763 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2764 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2765 }
2766 
2767 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2768 					   ext4_fsblk_t blk)
2769 {
2770 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2771 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2772 }
2773 
2774 static inline loff_t ext4_isize(struct super_block *sb,
2775 				struct ext4_inode *raw_inode)
2776 {
2777 	if (ext4_has_feature_largedir(sb) ||
2778 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2779 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2780 			le32_to_cpu(raw_inode->i_size_lo);
2781 
2782 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2783 }
2784 
2785 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2786 {
2787 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2788 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2789 }
2790 
2791 static inline
2792 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2793 					    ext4_group_t group)
2794 {
2795 	 struct ext4_group_info ***grp_info;
2796 	 long indexv, indexh;
2797 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2798 	 grp_info = EXT4_SB(sb)->s_group_info;
2799 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2800 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2801 	 return grp_info[indexv][indexh];
2802 }
2803 
2804 /*
2805  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2806  * the locking protocol documented in the comments of ext4_group_add()
2807  * in resize.c
2808  */
2809 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2810 {
2811 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2812 
2813 	smp_rmb();
2814 	return ngroups;
2815 }
2816 
2817 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2818 					     ext4_group_t block_group)
2819 {
2820 	return block_group >> sbi->s_log_groups_per_flex;
2821 }
2822 
2823 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2824 {
2825 	return 1 << sbi->s_log_groups_per_flex;
2826 }
2827 
2828 #define ext4_std_error(sb, errno)				\
2829 do {								\
2830 	if ((errno))						\
2831 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2832 } while (0)
2833 
2834 #ifdef CONFIG_SMP
2835 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2836  * counters. So we need to make sure we have free clusters more
2837  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2838  */
2839 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2840 #else
2841 #define EXT4_FREECLUSTERS_WATERMARK 0
2842 #endif
2843 
2844 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2845 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2846 {
2847 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2848 		     !inode_is_locked(inode));
2849 	down_write(&EXT4_I(inode)->i_data_sem);
2850 	if (newsize > EXT4_I(inode)->i_disksize)
2851 		EXT4_I(inode)->i_disksize = newsize;
2852 	up_write(&EXT4_I(inode)->i_data_sem);
2853 }
2854 
2855 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2856 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2857 {
2858 	int changed = 0;
2859 
2860 	if (newsize > inode->i_size) {
2861 		i_size_write(inode, newsize);
2862 		changed = 1;
2863 	}
2864 	if (newsize > EXT4_I(inode)->i_disksize) {
2865 		ext4_update_i_disksize(inode, newsize);
2866 		changed |= 2;
2867 	}
2868 	return changed;
2869 }
2870 
2871 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2872 				      loff_t len);
2873 
2874 struct ext4_group_info {
2875 	unsigned long   bb_state;
2876 	struct rb_root  bb_free_root;
2877 	ext4_grpblk_t	bb_first_free;	/* first free block */
2878 	ext4_grpblk_t	bb_free;	/* total free blocks */
2879 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2880 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2881 	struct          list_head bb_prealloc_list;
2882 #ifdef DOUBLE_CHECK
2883 	void            *bb_bitmap;
2884 #endif
2885 	struct rw_semaphore alloc_sem;
2886 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2887 					 * regions, index is order.
2888 					 * bb_counters[3] = 5 means
2889 					 * 5 free 8-block regions. */
2890 };
2891 
2892 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2893 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2894 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2895 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2896 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT		\
2897 	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
2898 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT		\
2899 	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
2900 
2901 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2902 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2903 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2904 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2905 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2906 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2907 
2908 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2909 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2910 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2911 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2912 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2913 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2914 
2915 #define EXT4_MAX_CONTENTION		8
2916 #define EXT4_CONTENTION_THRESHOLD	2
2917 
2918 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2919 					      ext4_group_t group)
2920 {
2921 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2922 }
2923 
2924 /*
2925  * Returns true if the filesystem is busy enough that attempts to
2926  * access the block group locks has run into contention.
2927  */
2928 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2929 {
2930 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2931 }
2932 
2933 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2934 {
2935 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2936 	if (spin_trylock(lock))
2937 		/*
2938 		 * We're able to grab the lock right away, so drop the
2939 		 * lock contention counter.
2940 		 */
2941 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2942 	else {
2943 		/*
2944 		 * The lock is busy, so bump the contention counter,
2945 		 * and then wait on the spin lock.
2946 		 */
2947 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2948 				  EXT4_MAX_CONTENTION);
2949 		spin_lock(lock);
2950 	}
2951 }
2952 
2953 static inline void ext4_unlock_group(struct super_block *sb,
2954 					ext4_group_t group)
2955 {
2956 	spin_unlock(ext4_group_lock_ptr(sb, group));
2957 }
2958 
2959 /*
2960  * Block validity checking
2961  */
2962 #define ext4_check_indirect_blockref(inode, bh)				\
2963 	ext4_check_blockref(__func__, __LINE__, inode,			\
2964 			    (__le32 *)(bh)->b_data,			\
2965 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2966 
2967 #define ext4_ind_check_inode(inode)					\
2968 	ext4_check_blockref(__func__, __LINE__, inode,			\
2969 			    EXT4_I(inode)->i_data,			\
2970 			    EXT4_NDIR_BLOCKS)
2971 
2972 /*
2973  * Inodes and files operations
2974  */
2975 
2976 /* dir.c */
2977 extern const struct file_operations ext4_dir_operations;
2978 
2979 /* file.c */
2980 extern const struct inode_operations ext4_file_inode_operations;
2981 extern const struct file_operations ext4_file_operations;
2982 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2983 
2984 /* inline.c */
2985 extern int ext4_get_max_inline_size(struct inode *inode);
2986 extern int ext4_find_inline_data_nolock(struct inode *inode);
2987 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2988 				 unsigned int len);
2989 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2990 
2991 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2992 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2993 					 struct inode *inode,
2994 					 loff_t pos, unsigned len,
2995 					 unsigned flags,
2996 					 struct page **pagep);
2997 extern int ext4_write_inline_data_end(struct inode *inode,
2998 				      loff_t pos, unsigned len,
2999 				      unsigned copied,
3000 				      struct page *page);
3001 extern struct buffer_head *
3002 ext4_journalled_write_inline_data(struct inode *inode,
3003 				  unsigned len,
3004 				  struct page *page);
3005 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3006 					   struct inode *inode,
3007 					   loff_t pos, unsigned len,
3008 					   unsigned flags,
3009 					   struct page **pagep,
3010 					   void **fsdata);
3011 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3012 					 unsigned len, unsigned copied,
3013 					 struct page *page);
3014 extern int ext4_try_add_inline_entry(handle_t *handle,
3015 				     struct ext4_filename *fname,
3016 				     struct inode *dir, struct inode *inode);
3017 extern int ext4_try_create_inline_dir(handle_t *handle,
3018 				      struct inode *parent,
3019 				      struct inode *inode);
3020 extern int ext4_read_inline_dir(struct file *filp,
3021 				struct dir_context *ctx,
3022 				int *has_inline_data);
3023 extern int htree_inlinedir_to_tree(struct file *dir_file,
3024 				   struct inode *dir, ext4_lblk_t block,
3025 				   struct dx_hash_info *hinfo,
3026 				   __u32 start_hash, __u32 start_minor_hash,
3027 				   int *has_inline_data);
3028 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3029 					struct ext4_filename *fname,
3030 					struct ext4_dir_entry_2 **res_dir,
3031 					int *has_inline_data);
3032 extern int ext4_delete_inline_entry(handle_t *handle,
3033 				    struct inode *dir,
3034 				    struct ext4_dir_entry_2 *de_del,
3035 				    struct buffer_head *bh,
3036 				    int *has_inline_data);
3037 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3038 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3039 					struct ext4_dir_entry_2 **parent_de,
3040 					int *retval);
3041 extern int ext4_inline_data_fiemap(struct inode *inode,
3042 				   struct fiemap_extent_info *fieinfo,
3043 				   int *has_inline, __u64 start, __u64 len);
3044 
3045 struct iomap;
3046 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3047 
3048 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3049 
3050 extern int ext4_convert_inline_data(struct inode *inode);
3051 
3052 static inline int ext4_has_inline_data(struct inode *inode)
3053 {
3054 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3055 	       EXT4_I(inode)->i_inline_off;
3056 }
3057 
3058 /* namei.c */
3059 extern const struct inode_operations ext4_dir_inode_operations;
3060 extern const struct inode_operations ext4_special_inode_operations;
3061 extern struct dentry *ext4_get_parent(struct dentry *child);
3062 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3063 				 struct ext4_dir_entry_2 *de,
3064 				 int blocksize, int csum_size,
3065 				 unsigned int parent_ino, int dotdot_real_len);
3066 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
3067 				   unsigned int blocksize);
3068 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
3069 					 struct inode *inode,
3070 					 struct buffer_head *bh);
3071 #define S_SHIFT 12
3072 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3073 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3074 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3075 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3076 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3077 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3078 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3079 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3080 };
3081 
3082 static inline void ext4_set_de_type(struct super_block *sb,
3083 				struct ext4_dir_entry_2 *de,
3084 				umode_t mode) {
3085 	if (ext4_has_feature_filetype(sb))
3086 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3087 }
3088 
3089 /* readpages.c */
3090 extern int ext4_mpage_readpages(struct address_space *mapping,
3091 				struct list_head *pages, struct page *page,
3092 				unsigned nr_pages, bool is_readahead);
3093 
3094 /* symlink.c */
3095 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3096 extern const struct inode_operations ext4_symlink_inode_operations;
3097 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3098 
3099 /* sysfs.c */
3100 extern int ext4_register_sysfs(struct super_block *sb);
3101 extern void ext4_unregister_sysfs(struct super_block *sb);
3102 extern int __init ext4_init_sysfs(void);
3103 extern void ext4_exit_sysfs(void);
3104 
3105 /* block_validity */
3106 extern void ext4_release_system_zone(struct super_block *sb);
3107 extern int ext4_setup_system_zone(struct super_block *sb);
3108 extern int __init ext4_init_system_zone(void);
3109 extern void ext4_exit_system_zone(void);
3110 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3111 				 ext4_fsblk_t start_blk,
3112 				 unsigned int count);
3113 extern int ext4_check_blockref(const char *, unsigned int,
3114 			       struct inode *, __le32 *, unsigned int);
3115 
3116 /* extents.c */
3117 struct ext4_ext_path;
3118 struct ext4_extent;
3119 
3120 /*
3121  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3122  * __le32.
3123  */
3124 #define EXT_MAX_BLOCKS	0xffffffff
3125 
3126 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
3127 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
3128 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3129 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3130 			       struct ext4_map_blocks *map, int flags);
3131 extern int ext4_ext_truncate(handle_t *, struct inode *);
3132 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3133 				 ext4_lblk_t end);
3134 extern void ext4_ext_init(struct super_block *);
3135 extern void ext4_ext_release(struct super_block *);
3136 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3137 			  loff_t len);
3138 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3139 					  loff_t offset, ssize_t len);
3140 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3141 			   struct ext4_map_blocks *map, int flags);
3142 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
3143 					 ext4_lblk_t lblocks);
3144 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3145 						   int num,
3146 						   struct ext4_ext_path *path);
3147 extern int ext4_can_extents_be_merged(struct inode *inode,
3148 				      struct ext4_extent *ex1,
3149 				      struct ext4_extent *ex2);
3150 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3151 				  struct ext4_ext_path **,
3152 				  struct ext4_extent *, int);
3153 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3154 					      struct ext4_ext_path **,
3155 					      int flags);
3156 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3157 extern int ext4_ext_check_inode(struct inode *inode);
3158 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3159 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3160 			__u64 start, __u64 len);
3161 extern int ext4_ext_precache(struct inode *inode);
3162 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
3163 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
3164 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3165 				struct inode *inode2, ext4_lblk_t lblk1,
3166 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3167 			     int mark_unwritten,int *err);
3168 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3169 
3170 /* move_extent.c */
3171 extern void ext4_double_down_write_data_sem(struct inode *first,
3172 					    struct inode *second);
3173 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3174 					  struct inode *donor_inode);
3175 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3176 			     __u64 start_orig, __u64 start_donor,
3177 			     __u64 len, __u64 *moved_len);
3178 
3179 /* page-io.c */
3180 extern int __init ext4_init_pageio(void);
3181 extern void ext4_exit_pageio(void);
3182 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3183 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3184 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3185 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3186 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3187 				struct writeback_control *wbc);
3188 extern void ext4_end_io_rsv_work(struct work_struct *work);
3189 extern void ext4_io_submit(struct ext4_io_submit *io);
3190 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3191 			       struct page *page,
3192 			       int len,
3193 			       struct writeback_control *wbc,
3194 			       bool keep_towrite);
3195 
3196 /* mmp.c */
3197 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3198 
3199 /*
3200  * Add new method to test whether block and inode bitmaps are properly
3201  * initialized. With uninit_bg reading the block from disk is not enough
3202  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3203  */
3204 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3205 
3206 static inline int bitmap_uptodate(struct buffer_head *bh)
3207 {
3208 	return (buffer_uptodate(bh) &&
3209 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3210 }
3211 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3212 {
3213 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3214 }
3215 
3216 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3217 
3218 /* For ioend & aio unwritten conversion wait queues */
3219 #define EXT4_WQ_HASH_SZ		37
3220 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3221 					    EXT4_WQ_HASH_SZ])
3222 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3223 
3224 extern int ext4_resize_begin(struct super_block *sb);
3225 extern void ext4_resize_end(struct super_block *sb);
3226 
3227 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3228 					      struct ext4_io_end *io_end)
3229 {
3230 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3231 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3232 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3233 	}
3234 }
3235 
3236 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3237 {
3238 	struct inode *inode = io_end->inode;
3239 
3240 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3241 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3242 		/* Wake up anyone waiting on unwritten extent conversion */
3243 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3244 			wake_up_all(ext4_ioend_wq(inode));
3245 	}
3246 }
3247 
3248 extern const struct iomap_ops ext4_iomap_ops;
3249 
3250 #endif	/* __KERNEL__ */
3251 
3252 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3253 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3254 
3255 #endif	/* _EXT4_H */
3256