xref: /linux/fs/ext4/ext4.h (revision 4e0ae876f77bc01a7e77724dea57b4b82bd53244)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  ext4.h
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/include/linux/minix_fs.h
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  */
16 
17 #ifndef _EXT4_H
18 #define _EXT4_H
19 
20 #include <linux/types.h>
21 #include <linux/blkdev.h>
22 #include <linux/magic.h>
23 #include <linux/jbd2.h>
24 #include <linux/quota.h>
25 #include <linux/rwsem.h>
26 #include <linux/rbtree.h>
27 #include <linux/seqlock.h>
28 #include <linux/mutex.h>
29 #include <linux/timer.h>
30 #include <linux/version.h>
31 #include <linux/wait.h>
32 #include <linux/sched/signal.h>
33 #include <linux/blockgroup_lock.h>
34 #include <linux/percpu_counter.h>
35 #include <linux/ratelimit.h>
36 #include <crypto/hash.h>
37 #include <linux/falloc.h>
38 #include <linux/percpu-rwsem.h>
39 #ifdef __KERNEL__
40 #include <linux/compat.h>
41 #endif
42 
43 #include <linux/fscrypt.h>
44 
45 #include <linux/compiler.h>
46 
47 /*
48  * The fourth extended filesystem constants/structures
49  */
50 
51 /*
52  * with AGGRESSIVE_CHECK allocator runs consistency checks over
53  * structures. these checks slow things down a lot
54  */
55 #define AGGRESSIVE_CHECK__
56 
57 /*
58  * with DOUBLE_CHECK defined mballoc creates persistent in-core
59  * bitmaps, maintains and uses them to check for double allocations
60  */
61 #define DOUBLE_CHECK__
62 
63 /*
64  * Define EXT4FS_DEBUG to produce debug messages
65  */
66 #undef EXT4FS_DEBUG
67 
68 /*
69  * Debug code
70  */
71 #ifdef EXT4FS_DEBUG
72 #define ext4_debug(f, a...)						\
73 	do {								\
74 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
75 			__FILE__, __LINE__, __func__);			\
76 		printk(KERN_DEBUG f, ## a);				\
77 	} while (0)
78 #else
79 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
80 #endif
81 
82 /*
83  * Turn on EXT_DEBUG to get lots of info about extents operations.
84  */
85 #define EXT_DEBUG__
86 #ifdef EXT_DEBUG
87 #define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
88 #else
89 #define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
90 #endif
91 
92 /* data type for block offset of block group */
93 typedef int ext4_grpblk_t;
94 
95 /* data type for filesystem-wide blocks number */
96 typedef unsigned long long ext4_fsblk_t;
97 
98 /* data type for file logical block number */
99 typedef __u32 ext4_lblk_t;
100 
101 /* data type for block group number */
102 typedef unsigned int ext4_group_t;
103 
104 enum SHIFT_DIRECTION {
105 	SHIFT_LEFT = 0,
106 	SHIFT_RIGHT,
107 };
108 
109 /*
110  * Flags used in mballoc's allocation_context flags field.
111  *
112  * Also used to show what's going on for debugging purposes when the
113  * flag field is exported via the traceport interface
114  */
115 
116 /* prefer goal again. length */
117 #define EXT4_MB_HINT_MERGE		0x0001
118 /* blocks already reserved */
119 #define EXT4_MB_HINT_RESERVED		0x0002
120 /* metadata is being allocated */
121 #define EXT4_MB_HINT_METADATA		0x0004
122 /* first blocks in the file */
123 #define EXT4_MB_HINT_FIRST		0x0008
124 /* search for the best chunk */
125 #define EXT4_MB_HINT_BEST		0x0010
126 /* data is being allocated */
127 #define EXT4_MB_HINT_DATA		0x0020
128 /* don't preallocate (for tails) */
129 #define EXT4_MB_HINT_NOPREALLOC		0x0040
130 /* allocate for locality group */
131 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
132 /* allocate goal blocks or none */
133 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
134 /* goal is meaningful */
135 #define EXT4_MB_HINT_TRY_GOAL		0x0200
136 /* blocks already pre-reserved by delayed allocation */
137 #define EXT4_MB_DELALLOC_RESERVED	0x0400
138 /* We are doing stream allocation */
139 #define EXT4_MB_STREAM_ALLOC		0x0800
140 /* Use reserved root blocks if needed */
141 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
142 /* Use blocks from reserved pool */
143 #define EXT4_MB_USE_RESERVED		0x2000
144 
145 struct ext4_allocation_request {
146 	/* target inode for block we're allocating */
147 	struct inode *inode;
148 	/* how many blocks we want to allocate */
149 	unsigned int len;
150 	/* logical block in target inode */
151 	ext4_lblk_t logical;
152 	/* the closest logical allocated block to the left */
153 	ext4_lblk_t lleft;
154 	/* the closest logical allocated block to the right */
155 	ext4_lblk_t lright;
156 	/* phys. target (a hint) */
157 	ext4_fsblk_t goal;
158 	/* phys. block for the closest logical allocated block to the left */
159 	ext4_fsblk_t pleft;
160 	/* phys. block for the closest logical allocated block to the right */
161 	ext4_fsblk_t pright;
162 	/* flags. see above EXT4_MB_HINT_* */
163 	unsigned int flags;
164 };
165 
166 /*
167  * Logical to physical block mapping, used by ext4_map_blocks()
168  *
169  * This structure is used to pass requests into ext4_map_blocks() as
170  * well as to store the information returned by ext4_map_blocks().  It
171  * takes less room on the stack than a struct buffer_head.
172  */
173 #define EXT4_MAP_NEW		(1 << BH_New)
174 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
175 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
176 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
177 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
178 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
179 
180 struct ext4_map_blocks {
181 	ext4_fsblk_t m_pblk;
182 	ext4_lblk_t m_lblk;
183 	unsigned int m_len;
184 	unsigned int m_flags;
185 };
186 
187 /*
188  * Flags for ext4_io_end->flags
189  */
190 #define	EXT4_IO_END_UNWRITTEN	0x0001
191 
192 /*
193  * For converting unwritten extents on a work queue. 'handle' is used for
194  * buffered writeback.
195  */
196 typedef struct ext4_io_end {
197 	struct list_head	list;		/* per-file finished IO list */
198 	handle_t		*handle;	/* handle reserved for extent
199 						 * conversion */
200 	struct inode		*inode;		/* file being written to */
201 	struct bio		*bio;		/* Linked list of completed
202 						 * bios covering the extent */
203 	unsigned int		flag;		/* unwritten or not */
204 	atomic_t		count;		/* reference counter */
205 	loff_t			offset;		/* offset in the file */
206 	ssize_t			size;		/* size of the extent */
207 } ext4_io_end_t;
208 
209 struct ext4_io_submit {
210 	struct writeback_control *io_wbc;
211 	struct bio		*io_bio;
212 	ext4_io_end_t		*io_end;
213 	sector_t		io_next_block;
214 };
215 
216 /*
217  * Special inodes numbers
218  */
219 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
220 #define EXT4_ROOT_INO		 2	/* Root inode */
221 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
222 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
223 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
224 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
225 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
226 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
227 
228 /* First non-reserved inode for old ext4 filesystems */
229 #define EXT4_GOOD_OLD_FIRST_INO	11
230 
231 /*
232  * Maximal count of links to a file
233  */
234 #define EXT4_LINK_MAX		65000
235 
236 /*
237  * Macro-instructions used to manage several block sizes
238  */
239 #define EXT4_MIN_BLOCK_SIZE		1024
240 #define	EXT4_MAX_BLOCK_SIZE		65536
241 #define EXT4_MIN_BLOCK_LOG_SIZE		10
242 #define EXT4_MAX_BLOCK_LOG_SIZE		16
243 #define EXT4_MAX_CLUSTER_LOG_SIZE	30
244 #ifdef __KERNEL__
245 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
246 #else
247 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
248 #endif
249 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
250 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
251 					 EXT4_SB(s)->s_cluster_bits)
252 #ifdef __KERNEL__
253 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
254 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
255 #else
256 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
257 #endif
258 #ifdef __KERNEL__
259 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
260 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
261 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
262 #else
263 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
264 				 EXT4_GOOD_OLD_INODE_SIZE : \
265 				 (s)->s_inode_size)
266 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
267 				 EXT4_GOOD_OLD_FIRST_INO : \
268 				 (s)->s_first_ino)
269 #endif
270 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
271 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
272 	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
273 								  blkbits))
274 
275 /* Translate a block number to a cluster number */
276 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
277 /* Translate a cluster number to a block number */
278 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
279 /* Translate # of blks to # of clusters */
280 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
281 				 (sbi)->s_cluster_bits)
282 /* Mask out the low bits to get the starting block of the cluster */
283 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
284 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
285 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
286 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
287 /* Get the cluster offset */
288 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
289 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
290 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
291 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
292 
293 /*
294  * Structure of a blocks group descriptor
295  */
296 struct ext4_group_desc
297 {
298 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
299 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
300 	__le32	bg_inode_table_lo;	/* Inodes table block */
301 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
302 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
303 	__le16	bg_used_dirs_count_lo;	/* Directories count */
304 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
305 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
306 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
307 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
308 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
309 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
310 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
311 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
312 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
313 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
314 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
315 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
316 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
317 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
318 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
319 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
320 	__u32   bg_reserved;
321 };
322 
323 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
324 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
325 	 sizeof(__le16))
326 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
327 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
328 	 sizeof(__le16))
329 
330 /*
331  * Structure of a flex block group info
332  */
333 
334 struct flex_groups {
335 	atomic64_t	free_clusters;
336 	atomic_t	free_inodes;
337 	atomic_t	used_dirs;
338 };
339 
340 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
341 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
342 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
343 
344 /*
345  * Macro-instructions used to manage group descriptors
346  */
347 #define EXT4_MIN_DESC_SIZE		32
348 #define EXT4_MIN_DESC_SIZE_64BIT	64
349 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
350 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
351 #ifdef __KERNEL__
352 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
353 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
354 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
355 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
356 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
357 #else
358 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
359 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
360 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
361 #endif
362 
363 /*
364  * Constants relative to the data blocks
365  */
366 #define	EXT4_NDIR_BLOCKS		12
367 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
368 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
369 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
370 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
371 
372 /*
373  * Inode flags
374  */
375 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
376 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
377 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
378 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
379 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
380 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
381 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
382 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
383 /* Reserved for compression usage... */
384 #define EXT4_DIRTY_FL			0x00000100
385 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
386 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
387 	/* nb: was previously EXT2_ECOMPR_FL */
388 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
389 /* End compression flags --- maybe not all used */
390 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
391 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
392 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
393 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
394 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
395 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
396 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
397 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
398 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
399 #define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
400 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
401 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
402 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
403 
404 #define EXT4_FL_USER_VISIBLE		0x304BDFFF /* User visible flags */
405 #define EXT4_FL_USER_MODIFIABLE		0x204BC0FF /* User modifiable flags */
406 
407 /* Flags we can manipulate with through EXT4_IOC_FSSETXATTR */
408 #define EXT4_FL_XFLAG_VISIBLE		(EXT4_SYNC_FL | \
409 					 EXT4_IMMUTABLE_FL | \
410 					 EXT4_APPEND_FL | \
411 					 EXT4_NODUMP_FL | \
412 					 EXT4_NOATIME_FL | \
413 					 EXT4_PROJINHERIT_FL)
414 
415 /* Flags that should be inherited by new inodes from their parent. */
416 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
417 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
418 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
419 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
420 			   EXT4_PROJINHERIT_FL)
421 
422 /* Flags that are appropriate for regular files (all but dir-specific ones). */
423 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
424 
425 /* Flags that are appropriate for non-directories/regular files. */
426 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
427 
428 /* The only flags that should be swapped */
429 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
430 
431 /* Mask out flags that are inappropriate for the given type of inode. */
432 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
433 {
434 	if (S_ISDIR(mode))
435 		return flags;
436 	else if (S_ISREG(mode))
437 		return flags & EXT4_REG_FLMASK;
438 	else
439 		return flags & EXT4_OTHER_FLMASK;
440 }
441 
442 /*
443  * Inode flags used for atomic set/get
444  */
445 enum {
446 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
447 	EXT4_INODE_UNRM		= 1,	/* Undelete */
448 	EXT4_INODE_COMPR	= 2,	/* Compress file */
449 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
450 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
451 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
452 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
453 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
454 /* Reserved for compression usage... */
455 	EXT4_INODE_DIRTY	= 8,
456 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
457 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
458 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
459 /* End compression flags --- maybe not all used */
460 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
461 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
462 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
463 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
464 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
465 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
466 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
467 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
468 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
469 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
470 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
471 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
472 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
473 };
474 
475 /*
476  * Since it's pretty easy to mix up bit numbers and hex values, we use a
477  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
478  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
479  * any extra space in the compiled kernel image, otherwise, the build will fail.
480  * It's important that these values are the same, since we are using
481  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
482  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
483  * values found in ext2, ext3 and ext4 filesystems, and of course the values
484  * defined in e2fsprogs.
485  *
486  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
487  */
488 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
489 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
490 
491 static inline void ext4_check_flag_values(void)
492 {
493 	CHECK_FLAG_VALUE(SECRM);
494 	CHECK_FLAG_VALUE(UNRM);
495 	CHECK_FLAG_VALUE(COMPR);
496 	CHECK_FLAG_VALUE(SYNC);
497 	CHECK_FLAG_VALUE(IMMUTABLE);
498 	CHECK_FLAG_VALUE(APPEND);
499 	CHECK_FLAG_VALUE(NODUMP);
500 	CHECK_FLAG_VALUE(NOATIME);
501 	CHECK_FLAG_VALUE(DIRTY);
502 	CHECK_FLAG_VALUE(COMPRBLK);
503 	CHECK_FLAG_VALUE(NOCOMPR);
504 	CHECK_FLAG_VALUE(ENCRYPT);
505 	CHECK_FLAG_VALUE(INDEX);
506 	CHECK_FLAG_VALUE(IMAGIC);
507 	CHECK_FLAG_VALUE(JOURNAL_DATA);
508 	CHECK_FLAG_VALUE(NOTAIL);
509 	CHECK_FLAG_VALUE(DIRSYNC);
510 	CHECK_FLAG_VALUE(TOPDIR);
511 	CHECK_FLAG_VALUE(HUGE_FILE);
512 	CHECK_FLAG_VALUE(EXTENTS);
513 	CHECK_FLAG_VALUE(EA_INODE);
514 	CHECK_FLAG_VALUE(EOFBLOCKS);
515 	CHECK_FLAG_VALUE(INLINE_DATA);
516 	CHECK_FLAG_VALUE(PROJINHERIT);
517 	CHECK_FLAG_VALUE(RESERVED);
518 }
519 
520 /* Used to pass group descriptor data when online resize is done */
521 struct ext4_new_group_input {
522 	__u32 group;		/* Group number for this data */
523 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
524 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
525 	__u64 inode_table;	/* Absolute block number of inode table start */
526 	__u32 blocks_count;	/* Total number of blocks in this group */
527 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
528 	__u16 unused;
529 };
530 
531 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
532 struct compat_ext4_new_group_input {
533 	u32 group;
534 	compat_u64 block_bitmap;
535 	compat_u64 inode_bitmap;
536 	compat_u64 inode_table;
537 	u32 blocks_count;
538 	u16 reserved_blocks;
539 	u16 unused;
540 };
541 #endif
542 
543 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
544 struct ext4_new_group_data {
545 	__u32 group;
546 	__u64 block_bitmap;
547 	__u64 inode_bitmap;
548 	__u64 inode_table;
549 	__u32 blocks_count;
550 	__u16 reserved_blocks;
551 	__u16 mdata_blocks;
552 	__u32 free_clusters_count;
553 };
554 
555 /* Indexes used to index group tables in ext4_new_group_data */
556 enum {
557 	BLOCK_BITMAP = 0,	/* block bitmap */
558 	INODE_BITMAP,		/* inode bitmap */
559 	INODE_TABLE,		/* inode tables */
560 	GROUP_TABLE_COUNT,
561 };
562 
563 /*
564  * Flags used by ext4_map_blocks()
565  */
566 	/* Allocate any needed blocks and/or convert an unwritten
567 	   extent to be an initialized ext4 */
568 #define EXT4_GET_BLOCKS_CREATE			0x0001
569 	/* Request the creation of an unwritten extent */
570 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
571 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
572 						 EXT4_GET_BLOCKS_CREATE)
573 	/* Caller is from the delayed allocation writeout path
574 	 * finally doing the actual allocation of delayed blocks */
575 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
576 	/* caller is from the direct IO path, request to creation of an
577 	unwritten extents if not allocated, split the unwritten
578 	extent if blocks has been preallocated already*/
579 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
580 #define EXT4_GET_BLOCKS_CONVERT			0x0010
581 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
582 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
583 	/* Convert extent to initialized after IO complete */
584 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
585 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
586 	/* Eventual metadata allocation (due to growing extent tree)
587 	 * should not fail, so try to use reserved blocks for that.*/
588 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
589 	/* Don't normalize allocation size (used for fallocate) */
590 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
591 	/* Request will not result in inode size update (user for fallocate) */
592 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
593 	/* Convert written extents to unwritten */
594 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
595 	/* Write zeros to newly created written extents */
596 #define EXT4_GET_BLOCKS_ZERO			0x0200
597 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
598 					EXT4_GET_BLOCKS_ZERO)
599 	/* Caller will submit data before dropping transaction handle. This
600 	 * allows jbd2 to avoid submitting data before commit. */
601 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
602 
603 /*
604  * The bit position of these flags must not overlap with any of the
605  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
606  * read_extent_tree_block(), ext4_split_extent_at(),
607  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
608  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
609  * caching the extents when reading from the extent tree while a
610  * truncate or punch hole operation is in progress.
611  */
612 #define EXT4_EX_NOCACHE				0x40000000
613 #define EXT4_EX_FORCE_CACHE			0x20000000
614 
615 /*
616  * Flags used by ext4_free_blocks
617  */
618 #define EXT4_FREE_BLOCKS_METADATA		0x0001
619 #define EXT4_FREE_BLOCKS_FORGET			0x0002
620 #define EXT4_FREE_BLOCKS_VALIDATED		0x0004
621 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE		0x0008
622 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
623 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
624 #define EXT4_FREE_BLOCKS_RERESERVE_CLUSTER      0x0040
625 
626 /*
627  * ioctl commands
628  */
629 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
630 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
631 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
632 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
633 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
634 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
635 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
636 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
637 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
638 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
639 #define EXT4_IOC_MIGRATE		_IO('f', 9)
640  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
641  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
642 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
643 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
644 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
645 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
646 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
647 #define EXT4_IOC_SET_ENCRYPTION_POLICY	FS_IOC_SET_ENCRYPTION_POLICY
648 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	FS_IOC_GET_ENCRYPTION_PWSALT
649 #define EXT4_IOC_GET_ENCRYPTION_POLICY	FS_IOC_GET_ENCRYPTION_POLICY
650 
651 #define EXT4_IOC_FSGETXATTR		FS_IOC_FSGETXATTR
652 #define EXT4_IOC_FSSETXATTR		FS_IOC_FSSETXATTR
653 
654 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
655 
656 /*
657  * Flags for going down operation
658  */
659 #define EXT4_GOING_FLAGS_DEFAULT		0x0	/* going down */
660 #define EXT4_GOING_FLAGS_LOGFLUSH		0x1	/* flush log but not data */
661 #define EXT4_GOING_FLAGS_NOLOGFLUSH		0x2	/* don't flush log nor data */
662 
663 
664 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
665 /*
666  * ioctl commands in 32 bit emulation
667  */
668 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
669 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
670 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
671 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
672 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
673 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
674 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
675 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
676 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
677 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
678 #endif
679 
680 /* Max physical block we can address w/o extents */
681 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
682 
683 /* Max logical block we can support */
684 #define EXT4_MAX_LOGICAL_BLOCK		0xFFFFFFFF
685 
686 /*
687  * Structure of an inode on the disk
688  */
689 struct ext4_inode {
690 	__le16	i_mode;		/* File mode */
691 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
692 	__le32	i_size_lo;	/* Size in bytes */
693 	__le32	i_atime;	/* Access time */
694 	__le32	i_ctime;	/* Inode Change time */
695 	__le32	i_mtime;	/* Modification time */
696 	__le32	i_dtime;	/* Deletion Time */
697 	__le16	i_gid;		/* Low 16 bits of Group Id */
698 	__le16	i_links_count;	/* Links count */
699 	__le32	i_blocks_lo;	/* Blocks count */
700 	__le32	i_flags;	/* File flags */
701 	union {
702 		struct {
703 			__le32  l_i_version;
704 		} linux1;
705 		struct {
706 			__u32  h_i_translator;
707 		} hurd1;
708 		struct {
709 			__u32  m_i_reserved1;
710 		} masix1;
711 	} osd1;				/* OS dependent 1 */
712 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
713 	__le32	i_generation;	/* File version (for NFS) */
714 	__le32	i_file_acl_lo;	/* File ACL */
715 	__le32	i_size_high;
716 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
717 	union {
718 		struct {
719 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
720 			__le16	l_i_file_acl_high;
721 			__le16	l_i_uid_high;	/* these 2 fields */
722 			__le16	l_i_gid_high;	/* were reserved2[0] */
723 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
724 			__le16	l_i_reserved;
725 		} linux2;
726 		struct {
727 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
728 			__u16	h_i_mode_high;
729 			__u16	h_i_uid_high;
730 			__u16	h_i_gid_high;
731 			__u32	h_i_author;
732 		} hurd2;
733 		struct {
734 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
735 			__le16	m_i_file_acl_high;
736 			__u32	m_i_reserved2[2];
737 		} masix2;
738 	} osd2;				/* OS dependent 2 */
739 	__le16	i_extra_isize;
740 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
741 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
742 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
743 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
744 	__le32  i_crtime;       /* File Creation time */
745 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
746 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
747 	__le32	i_projid;	/* Project ID */
748 };
749 
750 struct move_extent {
751 	__u32 reserved;		/* should be zero */
752 	__u32 donor_fd;		/* donor file descriptor */
753 	__u64 orig_start;	/* logical start offset in block for orig */
754 	__u64 donor_start;	/* logical start offset in block for donor */
755 	__u64 len;		/* block length to be moved */
756 	__u64 moved_len;	/* moved block length */
757 };
758 
759 #define EXT4_EPOCH_BITS 2
760 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
761 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
762 
763 /*
764  * Extended fields will fit into an inode if the filesystem was formatted
765  * with large inodes (-I 256 or larger) and there are not currently any EAs
766  * consuming all of the available space. For new inodes we always reserve
767  * enough space for the kernel's known extended fields, but for inodes
768  * created with an old kernel this might not have been the case. None of
769  * the extended inode fields is critical for correct filesystem operation.
770  * This macro checks if a certain field fits in the inode. Note that
771  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
772  */
773 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
774 	((offsetof(typeof(*ext4_inode), field) +	\
775 	  sizeof((ext4_inode)->field))			\
776 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
777 	    (einode)->i_extra_isize))			\
778 
779 /*
780  * We use an encoding that preserves the times for extra epoch "00":
781  *
782  * extra  msb of                         adjust for signed
783  * epoch  32-bit                         32-bit tv_sec to
784  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
785  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
786  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
787  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
788  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
789  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
790  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
791  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
792  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
793  *
794  * Note that previous versions of the kernel on 64-bit systems would
795  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
796  * 1970.  e2fsck will correct this, assuming that it is run on the
797  * affected filesystem before 2242.
798  */
799 
800 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
801 {
802 	u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
803 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
804 }
805 
806 static inline void ext4_decode_extra_time(struct timespec64 *time,
807 					  __le32 extra)
808 {
809 	if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK))) {
810 
811 #if 1
812 		/* Handle legacy encoding of pre-1970 dates with epoch
813 		 * bits 1,1. (This backwards compatibility may be removed
814 		 * at the discretion of the ext4 developers.)
815 		 */
816 		u64 extra_bits = le32_to_cpu(extra) & EXT4_EPOCH_MASK;
817 		if (extra_bits == 3 && ((time->tv_sec) & 0x80000000) != 0)
818 			extra_bits = 0;
819 		time->tv_sec += extra_bits << 32;
820 #else
821 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
822 #endif
823 	}
824 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
825 }
826 
827 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)				\
828 do {										\
829 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);		\
830 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
831 		(raw_inode)->xtime ## _extra =					\
832 				ext4_encode_extra_time(&(inode)->xtime);	\
833 		}								\
834 } while (0)
835 
836 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
837 do {									       \
838 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
839 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
840 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
841 		(raw_inode)->xtime ## _extra =				       \
842 				ext4_encode_extra_time(&(einode)->xtime);      \
843 } while (0)
844 
845 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)				\
846 do {										\
847 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);	\
848 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {	\
849 		ext4_decode_extra_time(&(inode)->xtime,				\
850 				       raw_inode->xtime ## _extra);		\
851 		}								\
852 	else									\
853 		(inode)->xtime.tv_nsec = 0;					\
854 } while (0)
855 
856 
857 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
858 do {									       \
859 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
860 		(einode)->xtime.tv_sec = 				       \
861 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
862 	else								       \
863 		(einode)->xtime.tv_sec = 0;				       \
864 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
865 		ext4_decode_extra_time(&(einode)->xtime,		       \
866 				       raw_inode->xtime ## _extra);	       \
867 	else								       \
868 		(einode)->xtime.tv_nsec = 0;				       \
869 } while (0)
870 
871 #define i_disk_version osd1.linux1.l_i_version
872 
873 #if defined(__KERNEL__) || defined(__linux__)
874 #define i_reserved1	osd1.linux1.l_i_reserved1
875 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
876 #define i_blocks_high	osd2.linux2.l_i_blocks_high
877 #define i_uid_low	i_uid
878 #define i_gid_low	i_gid
879 #define i_uid_high	osd2.linux2.l_i_uid_high
880 #define i_gid_high	osd2.linux2.l_i_gid_high
881 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
882 
883 #elif defined(__GNU__)
884 
885 #define i_translator	osd1.hurd1.h_i_translator
886 #define i_uid_high	osd2.hurd2.h_i_uid_high
887 #define i_gid_high	osd2.hurd2.h_i_gid_high
888 #define i_author	osd2.hurd2.h_i_author
889 
890 #elif defined(__masix__)
891 
892 #define i_reserved1	osd1.masix1.m_i_reserved1
893 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
894 #define i_reserved2	osd2.masix2.m_i_reserved2
895 
896 #endif /* defined(__KERNEL__) || defined(__linux__) */
897 
898 #include "extents_status.h"
899 
900 /*
901  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
902  *
903  * These are needed to avoid lockdep false positives when we need to
904  * allocate blocks to the quota inode during ext4_map_blocks(), while
905  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
906  * do quota tracking for the quota inode, this avoids deadlock (as
907  * well as infinite recursion, since it isn't turtles all the way
908  * down...)
909  *
910  *  I_DATA_SEM_NORMAL - Used for most inodes
911  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
912  *			  where the second inode has larger inode number
913  *			  than the first
914  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
915  */
916 enum {
917 	I_DATA_SEM_NORMAL = 0,
918 	I_DATA_SEM_OTHER,
919 	I_DATA_SEM_QUOTA,
920 };
921 
922 
923 /*
924  * fourth extended file system inode data in memory
925  */
926 struct ext4_inode_info {
927 	__le32	i_data[15];	/* unconverted */
928 	__u32	i_dtime;
929 	ext4_fsblk_t	i_file_acl;
930 
931 	/*
932 	 * i_block_group is the number of the block group which contains
933 	 * this file's inode.  Constant across the lifetime of the inode,
934 	 * it is used for making block allocation decisions - we try to
935 	 * place a file's data blocks near its inode block, and new inodes
936 	 * near to their parent directory's inode.
937 	 */
938 	ext4_group_t	i_block_group;
939 	ext4_lblk_t	i_dir_start_lookup;
940 #if (BITS_PER_LONG < 64)
941 	unsigned long	i_state_flags;		/* Dynamic state flags */
942 #endif
943 	unsigned long	i_flags;
944 
945 	/*
946 	 * Extended attributes can be read independently of the main file
947 	 * data. Taking i_mutex even when reading would cause contention
948 	 * between readers of EAs and writers of regular file data, so
949 	 * instead we synchronize on xattr_sem when reading or changing
950 	 * EAs.
951 	 */
952 	struct rw_semaphore xattr_sem;
953 
954 	struct list_head i_orphan;	/* unlinked but open inodes */
955 
956 	/*
957 	 * i_disksize keeps track of what the inode size is ON DISK, not
958 	 * in memory.  During truncate, i_size is set to the new size by
959 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
960 	 * set i_disksize to 0 until the truncate is actually under way.
961 	 *
962 	 * The intent is that i_disksize always represents the blocks which
963 	 * are used by this file.  This allows recovery to restart truncate
964 	 * on orphans if we crash during truncate.  We actually write i_disksize
965 	 * into the on-disk inode when writing inodes out, instead of i_size.
966 	 *
967 	 * The only time when i_disksize and i_size may be different is when
968 	 * a truncate is in progress.  The only things which change i_disksize
969 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
970 	 */
971 	loff_t	i_disksize;
972 
973 	/*
974 	 * i_data_sem is for serialising ext4_truncate() against
975 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
976 	 * data tree are chopped off during truncate. We can't do that in
977 	 * ext4 because whenever we perform intermediate commits during
978 	 * truncate, the inode and all the metadata blocks *must* be in a
979 	 * consistent state which allows truncation of the orphans to restart
980 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
981 	 * by other means, so we have i_data_sem.
982 	 */
983 	struct rw_semaphore i_data_sem;
984 	/*
985 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
986 	 * operations. We have to make sure that new page cannot be faulted in
987 	 * a section of the inode that is being punched. We cannot easily use
988 	 * i_data_sem for this since we need protection for the whole punch
989 	 * operation and i_data_sem ranks below transaction start so we have
990 	 * to occasionally drop it.
991 	 */
992 	struct rw_semaphore i_mmap_sem;
993 	struct inode vfs_inode;
994 	struct jbd2_inode *jinode;
995 
996 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
997 
998 	/*
999 	 * File creation time. Its function is same as that of
1000 	 * struct timespec64 i_{a,c,m}time in the generic inode.
1001 	 */
1002 	struct timespec64 i_crtime;
1003 
1004 	/* mballoc */
1005 	struct list_head i_prealloc_list;
1006 	spinlock_t i_prealloc_lock;
1007 
1008 	/* extents status tree */
1009 	struct ext4_es_tree i_es_tree;
1010 	rwlock_t i_es_lock;
1011 	struct list_head i_es_list;
1012 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1013 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1014 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1015 					   extents to shrink. Protected by
1016 					   i_es_lock  */
1017 
1018 	/* ialloc */
1019 	ext4_group_t	i_last_alloc_group;
1020 
1021 	/* allocation reservation info for delalloc */
1022 	/* In case of bigalloc, this refer to clusters rather than blocks */
1023 	unsigned int i_reserved_data_blocks;
1024 	ext4_lblk_t i_da_metadata_calc_last_lblock;
1025 	int i_da_metadata_calc_len;
1026 
1027 	/* pending cluster reservations for bigalloc file systems */
1028 	struct ext4_pending_tree i_pending_tree;
1029 
1030 	/* on-disk additional length */
1031 	__u16 i_extra_isize;
1032 
1033 	/* Indicate the inline data space. */
1034 	u16 i_inline_off;
1035 	u16 i_inline_size;
1036 
1037 #ifdef CONFIG_QUOTA
1038 	/* quota space reservation, managed internally by quota code */
1039 	qsize_t i_reserved_quota;
1040 #endif
1041 
1042 	/* Lock protecting lists below */
1043 	spinlock_t i_completed_io_lock;
1044 	/*
1045 	 * Completed IOs that need unwritten extents handling and have
1046 	 * transaction reserved
1047 	 */
1048 	struct list_head i_rsv_conversion_list;
1049 	struct work_struct i_rsv_conversion_work;
1050 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1051 
1052 	spinlock_t i_block_reservation_lock;
1053 
1054 	/*
1055 	 * Transactions that contain inode's metadata needed to complete
1056 	 * fsync and fdatasync, respectively.
1057 	 */
1058 	tid_t i_sync_tid;
1059 	tid_t i_datasync_tid;
1060 
1061 #ifdef CONFIG_QUOTA
1062 	struct dquot *i_dquot[MAXQUOTAS];
1063 #endif
1064 
1065 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1066 	__u32 i_csum_seed;
1067 
1068 	kprojid_t i_projid;
1069 };
1070 
1071 /*
1072  * File system states
1073  */
1074 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1075 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1076 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1077 
1078 /*
1079  * Misc. filesystem flags
1080  */
1081 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1082 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1083 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1084 
1085 /*
1086  * Mount flags set via mount options or defaults
1087  */
1088 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1089 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1090 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1091 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1092 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1093 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1094 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1095 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1096 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1097 #ifdef CONFIG_FS_DAX
1098 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
1099 #else
1100 #define EXT4_MOUNT_DAX			0
1101 #endif
1102 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1103 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1104 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1105 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1106 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1107 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1108 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1109 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1110 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1111 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1112 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1113 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1114 						 * enable enforcement for hidden
1115 						 * quota files */
1116 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1117 						  * enforcement for hidden quota
1118 						  * files */
1119 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1120 						  * enforcement */
1121 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1122 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1123 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1124 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
1125 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1126 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1127 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1128 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1129 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1130 
1131 /*
1132  * Mount flags set either automatically (could not be set by mount option)
1133  * based on per file system feature or property or in special cases such as
1134  * distinguishing between explicit mount option definition and default.
1135  */
1136 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1137 						      specified delalloc */
1138 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1139 						      size of blocksize * 8
1140 						      blocks */
1141 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1142 						      file systems */
1143 
1144 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1145 						specified journal checksum */
1146 
1147 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1148 						~EXT4_MOUNT_##opt
1149 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1150 						EXT4_MOUNT_##opt
1151 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1152 					 EXT4_MOUNT_##opt)
1153 
1154 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1155 						~EXT4_MOUNT2_##opt
1156 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1157 						EXT4_MOUNT2_##opt
1158 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1159 					 EXT4_MOUNT2_##opt)
1160 
1161 #define ext4_test_and_set_bit		__test_and_set_bit_le
1162 #define ext4_set_bit			__set_bit_le
1163 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1164 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1165 #define ext4_clear_bit			__clear_bit_le
1166 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1167 #define ext4_test_bit			test_bit_le
1168 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1169 #define ext4_find_next_bit		find_next_bit_le
1170 
1171 extern void ext4_set_bits(void *bm, int cur, int len);
1172 
1173 /*
1174  * Maximal mount counts between two filesystem checks
1175  */
1176 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1177 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1178 
1179 /*
1180  * Behaviour when detecting errors
1181  */
1182 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1183 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1184 #define EXT4_ERRORS_PANIC		3	/* Panic */
1185 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1186 
1187 /* Metadata checksum algorithm codes */
1188 #define EXT4_CRC32C_CHKSUM		1
1189 
1190 /*
1191  * Structure of the super block
1192  */
1193 struct ext4_super_block {
1194 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1195 	__le32	s_blocks_count_lo;	/* Blocks count */
1196 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1197 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1198 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1199 	__le32	s_first_data_block;	/* First Data Block */
1200 	__le32	s_log_block_size;	/* Block size */
1201 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1202 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1203 	__le32	s_clusters_per_group;	/* # Clusters per group */
1204 	__le32	s_inodes_per_group;	/* # Inodes per group */
1205 	__le32	s_mtime;		/* Mount time */
1206 /*30*/	__le32	s_wtime;		/* Write time */
1207 	__le16	s_mnt_count;		/* Mount count */
1208 	__le16	s_max_mnt_count;	/* Maximal mount count */
1209 	__le16	s_magic;		/* Magic signature */
1210 	__le16	s_state;		/* File system state */
1211 	__le16	s_errors;		/* Behaviour when detecting errors */
1212 	__le16	s_minor_rev_level;	/* minor revision level */
1213 /*40*/	__le32	s_lastcheck;		/* time of last check */
1214 	__le32	s_checkinterval;	/* max. time between checks */
1215 	__le32	s_creator_os;		/* OS */
1216 	__le32	s_rev_level;		/* Revision level */
1217 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1218 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1219 	/*
1220 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1221 	 *
1222 	 * Note: the difference between the compatible feature set and
1223 	 * the incompatible feature set is that if there is a bit set
1224 	 * in the incompatible feature set that the kernel doesn't
1225 	 * know about, it should refuse to mount the filesystem.
1226 	 *
1227 	 * e2fsck's requirements are more strict; if it doesn't know
1228 	 * about a feature in either the compatible or incompatible
1229 	 * feature set, it must abort and not try to meddle with
1230 	 * things it doesn't understand...
1231 	 */
1232 	__le32	s_first_ino;		/* First non-reserved inode */
1233 	__le16  s_inode_size;		/* size of inode structure */
1234 	__le16	s_block_group_nr;	/* block group # of this superblock */
1235 	__le32	s_feature_compat;	/* compatible feature set */
1236 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1237 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1238 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1239 /*78*/	char	s_volume_name[16];	/* volume name */
1240 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
1241 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1242 	/*
1243 	 * Performance hints.  Directory preallocation should only
1244 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1245 	 */
1246 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1247 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1248 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1249 	/*
1250 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1251 	 */
1252 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1253 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1254 	__le32	s_journal_dev;		/* device number of journal file */
1255 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1256 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1257 	__u8	s_def_hash_version;	/* Default hash version to use */
1258 	__u8	s_jnl_backup_type;
1259 	__le16  s_desc_size;		/* size of group descriptor */
1260 /*100*/	__le32	s_default_mount_opts;
1261 	__le32	s_first_meta_bg;	/* First metablock block group */
1262 	__le32	s_mkfs_time;		/* When the filesystem was created */
1263 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1264 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1265 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1266 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1267 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1268 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1269 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1270 	__le32	s_flags;		/* Miscellaneous flags */
1271 	__le16  s_raid_stride;		/* RAID stride */
1272 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1273 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1274 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1275 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1276 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1277 	__u8	s_encryption_level;	/* versioning level for encryption */
1278 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1279 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1280 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1281 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1282 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1283 					      snapshot's future use */
1284 	__le32	s_snapshot_list;	/* inode number of the head of the
1285 					   on-disk snapshot list */
1286 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1287 	__le32	s_error_count;		/* number of fs errors */
1288 	__le32	s_first_error_time;	/* first time an error happened */
1289 	__le32	s_first_error_ino;	/* inode involved in first error */
1290 	__le64	s_first_error_block;	/* block involved of first error */
1291 	__u8	s_first_error_func[32] __nonstring;	/* function where the error happened */
1292 	__le32	s_first_error_line;	/* line number where error happened */
1293 	__le32	s_last_error_time;	/* most recent time of an error */
1294 	__le32	s_last_error_ino;	/* inode involved in last error */
1295 	__le32	s_last_error_line;	/* line number where error happened */
1296 	__le64	s_last_error_block;	/* block involved of last error */
1297 	__u8	s_last_error_func[32] __nonstring;	/* function where the error happened */
1298 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1299 	__u8	s_mount_opts[64];
1300 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1301 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1302 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1303 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1304 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1305 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1306 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1307 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1308 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1309 	__u8	s_wtime_hi;
1310 	__u8	s_mtime_hi;
1311 	__u8	s_mkfs_time_hi;
1312 	__u8	s_lastcheck_hi;
1313 	__u8	s_first_error_time_hi;
1314 	__u8	s_last_error_time_hi;
1315 	__u8	s_pad[2];
1316 	__le32	s_reserved[96];		/* Padding to the end of the block */
1317 	__le32	s_checksum;		/* crc32c(superblock) */
1318 };
1319 
1320 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1321 
1322 #ifdef __KERNEL__
1323 
1324 /*
1325  * run-time mount flags
1326  */
1327 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1328 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1329 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1330 
1331 #ifdef CONFIG_FS_ENCRYPTION
1332 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1333 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1334 #else
1335 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1336 #endif
1337 
1338 /* Number of quota types we support */
1339 #define EXT4_MAXQUOTAS 3
1340 
1341 /*
1342  * fourth extended-fs super-block data in memory
1343  */
1344 struct ext4_sb_info {
1345 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1346 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1347 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1348 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1349 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1350 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1351 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1352 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1353 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1354 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1355 	unsigned long s_overhead;  /* # of fs overhead clusters */
1356 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1357 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1358 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1359 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1360 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1361 	struct buffer_head **s_group_desc;
1362 	unsigned int s_mount_opt;
1363 	unsigned int s_mount_opt2;
1364 	unsigned int s_mount_flags;
1365 	unsigned int s_def_mount_opt;
1366 	ext4_fsblk_t s_sb_block;
1367 	atomic64_t s_resv_clusters;
1368 	kuid_t s_resuid;
1369 	kgid_t s_resgid;
1370 	unsigned short s_mount_state;
1371 	unsigned short s_pad;
1372 	int s_addr_per_block_bits;
1373 	int s_desc_per_block_bits;
1374 	int s_inode_size;
1375 	int s_first_ino;
1376 	unsigned int s_inode_readahead_blks;
1377 	unsigned int s_inode_goal;
1378 	u32 s_hash_seed[4];
1379 	int s_def_hash_version;
1380 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1381 	struct percpu_counter s_freeclusters_counter;
1382 	struct percpu_counter s_freeinodes_counter;
1383 	struct percpu_counter s_dirs_counter;
1384 	struct percpu_counter s_dirtyclusters_counter;
1385 	struct blockgroup_lock *s_blockgroup_lock;
1386 	struct proc_dir_entry *s_proc;
1387 	struct kobject s_kobj;
1388 	struct completion s_kobj_unregister;
1389 	struct super_block *s_sb;
1390 
1391 	/* Journaling */
1392 	struct journal_s *s_journal;
1393 	struct list_head s_orphan;
1394 	struct mutex s_orphan_lock;
1395 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1396 	unsigned long s_commit_interval;
1397 	u32 s_max_batch_time;
1398 	u32 s_min_batch_time;
1399 	struct block_device *journal_bdev;
1400 #ifdef CONFIG_QUOTA
1401 	/* Names of quota files with journalled quota */
1402 	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1403 	int s_jquota_fmt;			/* Format of quota to use */
1404 #endif
1405 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1406 	struct rb_root system_blks;
1407 
1408 #ifdef EXTENTS_STATS
1409 	/* ext4 extents stats */
1410 	unsigned long s_ext_min;
1411 	unsigned long s_ext_max;
1412 	unsigned long s_depth_max;
1413 	spinlock_t s_ext_stats_lock;
1414 	unsigned long s_ext_blocks;
1415 	unsigned long s_ext_extents;
1416 #endif
1417 
1418 	/* for buddy allocator */
1419 	struct ext4_group_info ***s_group_info;
1420 	struct inode *s_buddy_cache;
1421 	spinlock_t s_md_lock;
1422 	unsigned short *s_mb_offsets;
1423 	unsigned int *s_mb_maxs;
1424 	unsigned int s_group_info_size;
1425 	unsigned int s_mb_free_pending;
1426 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1427 						   after commit completed */
1428 
1429 	/* tunables */
1430 	unsigned long s_stripe;
1431 	unsigned int s_mb_stream_request;
1432 	unsigned int s_mb_max_to_scan;
1433 	unsigned int s_mb_min_to_scan;
1434 	unsigned int s_mb_stats;
1435 	unsigned int s_mb_order2_reqs;
1436 	unsigned int s_mb_group_prealloc;
1437 	unsigned int s_max_dir_size_kb;
1438 	/* where last allocation was done - for stream allocation */
1439 	unsigned long s_mb_last_group;
1440 	unsigned long s_mb_last_start;
1441 
1442 	/* stats for buddy allocator */
1443 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1444 	atomic_t s_bal_success;	/* we found long enough chunks */
1445 	atomic_t s_bal_allocated;	/* in blocks */
1446 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1447 	atomic_t s_bal_goals;	/* goal hits */
1448 	atomic_t s_bal_breaks;	/* too long searches */
1449 	atomic_t s_bal_2orders;	/* 2^order hits */
1450 	spinlock_t s_bal_lock;
1451 	unsigned long s_mb_buddies_generated;
1452 	unsigned long long s_mb_generation_time;
1453 	atomic_t s_mb_lost_chunks;
1454 	atomic_t s_mb_preallocated;
1455 	atomic_t s_mb_discarded;
1456 	atomic_t s_lock_busy;
1457 
1458 	/* locality groups */
1459 	struct ext4_locality_group __percpu *s_locality_groups;
1460 
1461 	/* for write statistics */
1462 	unsigned long s_sectors_written_start;
1463 	u64 s_kbytes_written;
1464 
1465 	/* the size of zero-out chunk */
1466 	unsigned int s_extent_max_zeroout_kb;
1467 
1468 	unsigned int s_log_groups_per_flex;
1469 	struct flex_groups *s_flex_groups;
1470 	ext4_group_t s_flex_groups_allocated;
1471 
1472 	/* workqueue for reserved extent conversions (buffered io) */
1473 	struct workqueue_struct *rsv_conversion_wq;
1474 
1475 	/* timer for periodic error stats printing */
1476 	struct timer_list s_err_report;
1477 
1478 	/* Lazy inode table initialization info */
1479 	struct ext4_li_request *s_li_request;
1480 	/* Wait multiplier for lazy initialization thread */
1481 	unsigned int s_li_wait_mult;
1482 
1483 	/* Kernel thread for multiple mount protection */
1484 	struct task_struct *s_mmp_tsk;
1485 
1486 	/* record the last minlen when FITRIM is called. */
1487 	atomic_t s_last_trim_minblks;
1488 
1489 	/* Reference to checksum algorithm driver via cryptoapi */
1490 	struct crypto_shash *s_chksum_driver;
1491 
1492 	/* Precomputed FS UUID checksum for seeding other checksums */
1493 	__u32 s_csum_seed;
1494 
1495 	/* Reclaim extents from extent status tree */
1496 	struct shrinker s_es_shrinker;
1497 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1498 	long s_es_nr_inode;
1499 	struct ext4_es_stats s_es_stats;
1500 	struct mb_cache *s_ea_block_cache;
1501 	struct mb_cache *s_ea_inode_cache;
1502 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1503 
1504 	/* Ratelimit ext4 messages. */
1505 	struct ratelimit_state s_err_ratelimit_state;
1506 	struct ratelimit_state s_warning_ratelimit_state;
1507 	struct ratelimit_state s_msg_ratelimit_state;
1508 
1509 	/* Barrier between changing inodes' journal flags and writepages ops. */
1510 	struct percpu_rw_semaphore s_journal_flag_rwsem;
1511 	struct dax_device *s_daxdev;
1512 };
1513 
1514 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1515 {
1516 	return sb->s_fs_info;
1517 }
1518 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1519 {
1520 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1521 }
1522 
1523 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1524 {
1525 	return ino == EXT4_ROOT_INO ||
1526 		(ino >= EXT4_FIRST_INO(sb) &&
1527 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1528 }
1529 
1530 /*
1531  * Inode dynamic state flags
1532  */
1533 enum {
1534 	EXT4_STATE_JDATA,		/* journaled data exists */
1535 	EXT4_STATE_NEW,			/* inode is newly created */
1536 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1537 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1538 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1539 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1540 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1541 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1542 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1543 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1544 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1545 };
1546 
1547 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1548 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1549 {									\
1550 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1551 }									\
1552 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1553 {									\
1554 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1555 }									\
1556 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1557 {									\
1558 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1559 }
1560 
1561 /* Add these declarations here only so that these functions can be
1562  * found by name.  Otherwise, they are very hard to locate. */
1563 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1564 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1565 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1566 EXT4_INODE_BIT_FNS(flag, flags, 0)
1567 
1568 /* Add these declarations here only so that these functions can be
1569  * found by name.  Otherwise, they are very hard to locate. */
1570 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1571 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1572 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1573 #if (BITS_PER_LONG < 64)
1574 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1575 
1576 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1577 {
1578 	(ei)->i_state_flags = 0;
1579 }
1580 #else
1581 EXT4_INODE_BIT_FNS(state, flags, 32)
1582 
1583 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1584 {
1585 	/* We depend on the fact that callers will set i_flags */
1586 }
1587 #endif
1588 #else
1589 /* Assume that user mode programs are passing in an ext4fs superblock, not
1590  * a kernel struct super_block.  This will allow us to call the feature-test
1591  * macros from user land. */
1592 #define EXT4_SB(sb)	(sb)
1593 #endif
1594 
1595 /*
1596  * Returns true if the inode is inode is encrypted
1597  */
1598 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1599 
1600 /*
1601  * Codes for operating systems
1602  */
1603 #define EXT4_OS_LINUX		0
1604 #define EXT4_OS_HURD		1
1605 #define EXT4_OS_MASIX		2
1606 #define EXT4_OS_FREEBSD		3
1607 #define EXT4_OS_LITES		4
1608 
1609 /*
1610  * Revision levels
1611  */
1612 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1613 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1614 
1615 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1616 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1617 
1618 #define EXT4_GOOD_OLD_INODE_SIZE 128
1619 
1620 /*
1621  * Feature set definitions
1622  */
1623 
1624 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1625 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1626 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1627 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1628 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1629 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1630 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1631 
1632 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1633 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1634 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1635 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1636 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1637 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1638 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1639 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1640 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1641 /*
1642  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1643  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1644  * all other data structures' checksums.  However, the METADATA_CSUM and
1645  * GDT_CSUM bits are mutually exclusive.
1646  */
1647 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1648 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1649 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1650 
1651 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1652 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1653 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1654 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1655 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1656 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1657 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1658 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1659 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1660 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1661 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1662 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1663 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1664 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1665 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1666 
1667 extern void ext4_update_dynamic_rev(struct super_block *sb);
1668 
1669 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1670 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1671 { \
1672 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1673 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1674 } \
1675 static inline void ext4_set_feature_##name(struct super_block *sb) \
1676 { \
1677 	ext4_update_dynamic_rev(sb); \
1678 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1679 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1680 } \
1681 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1682 { \
1683 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1684 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1685 }
1686 
1687 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1688 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1689 { \
1690 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1691 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1692 } \
1693 static inline void ext4_set_feature_##name(struct super_block *sb) \
1694 { \
1695 	ext4_update_dynamic_rev(sb); \
1696 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1697 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1698 } \
1699 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1700 { \
1701 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1702 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1703 }
1704 
1705 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1706 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1707 { \
1708 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1709 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1710 } \
1711 static inline void ext4_set_feature_##name(struct super_block *sb) \
1712 { \
1713 	ext4_update_dynamic_rev(sb); \
1714 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
1715 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1716 } \
1717 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1718 { \
1719 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1720 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1721 }
1722 
1723 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1724 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1725 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1726 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1727 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1728 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1729 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1730 
1731 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1732 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1733 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1734 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1735 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1736 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1737 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1738 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1739 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1740 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1741 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1742 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1743 
1744 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1745 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
1746 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
1747 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
1748 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
1749 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
1750 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
1751 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
1752 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
1753 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
1754 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
1755 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
1756 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
1757 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
1758 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
1759 
1760 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1761 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1762 					 EXT4_FEATURE_INCOMPAT_META_BG)
1763 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1764 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1765 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1766 
1767 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1768 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1769 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1770 					 EXT4_FEATURE_INCOMPAT_META_BG)
1771 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1772 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1773 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1774 
1775 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1776 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1777 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1778 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1779 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1780 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1781 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1782 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
1783 					 EXT4_FEATURE_INCOMPAT_MMP | \
1784 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1785 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1786 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
1787 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
1788 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1789 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1790 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1791 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1792 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1793 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1794 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1795 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1796 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1797 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
1798 					 EXT4_FEATURE_RO_COMPAT_PROJECT)
1799 
1800 #define EXTN_FEATURE_FUNCS(ver) \
1801 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1802 { \
1803 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1804 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1805 } \
1806 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1807 { \
1808 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1809 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1810 } \
1811 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1812 { \
1813 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1814 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1815 }
1816 
1817 EXTN_FEATURE_FUNCS(2)
1818 EXTN_FEATURE_FUNCS(3)
1819 EXTN_FEATURE_FUNCS(4)
1820 
1821 static inline bool ext4_has_compat_features(struct super_block *sb)
1822 {
1823 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1824 }
1825 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1826 {
1827 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1828 }
1829 static inline bool ext4_has_incompat_features(struct super_block *sb)
1830 {
1831 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
1832 }
1833 
1834 /*
1835  * Superblock flags
1836  */
1837 #define EXT4_FLAGS_RESIZING	0
1838 #define EXT4_FLAGS_SHUTDOWN	1
1839 
1840 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
1841 {
1842 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
1843 }
1844 
1845 
1846 /*
1847  * Default values for user and/or group using reserved blocks
1848  */
1849 #define	EXT4_DEF_RESUID		0
1850 #define	EXT4_DEF_RESGID		0
1851 
1852 /*
1853  * Default project ID
1854  */
1855 #define	EXT4_DEF_PROJID		0
1856 
1857 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1858 
1859 /*
1860  * Default mount options
1861  */
1862 #define EXT4_DEFM_DEBUG		0x0001
1863 #define EXT4_DEFM_BSDGROUPS	0x0002
1864 #define EXT4_DEFM_XATTR_USER	0x0004
1865 #define EXT4_DEFM_ACL		0x0008
1866 #define EXT4_DEFM_UID16		0x0010
1867 #define EXT4_DEFM_JMODE		0x0060
1868 #define EXT4_DEFM_JMODE_DATA	0x0020
1869 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1870 #define EXT4_DEFM_JMODE_WBACK	0x0060
1871 #define EXT4_DEFM_NOBARRIER	0x0100
1872 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1873 #define EXT4_DEFM_DISCARD	0x0400
1874 #define EXT4_DEFM_NODELALLOC	0x0800
1875 
1876 /*
1877  * Default journal batch times
1878  */
1879 #define EXT4_DEF_MIN_BATCH_TIME	0
1880 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1881 
1882 /*
1883  * Minimum number of groups in a flexgroup before we separate out
1884  * directories into the first block group of a flexgroup
1885  */
1886 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1887 
1888 /*
1889  * Structure of a directory entry
1890  */
1891 #define EXT4_NAME_LEN 255
1892 
1893 struct ext4_dir_entry {
1894 	__le32	inode;			/* Inode number */
1895 	__le16	rec_len;		/* Directory entry length */
1896 	__le16	name_len;		/* Name length */
1897 	char	name[EXT4_NAME_LEN];	/* File name */
1898 };
1899 
1900 /*
1901  * The new version of the directory entry.  Since EXT4 structures are
1902  * stored in intel byte order, and the name_len field could never be
1903  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1904  * file_type field.
1905  */
1906 struct ext4_dir_entry_2 {
1907 	__le32	inode;			/* Inode number */
1908 	__le16	rec_len;		/* Directory entry length */
1909 	__u8	name_len;		/* Name length */
1910 	__u8	file_type;
1911 	char	name[EXT4_NAME_LEN];	/* File name */
1912 };
1913 
1914 /*
1915  * This is a bogus directory entry at the end of each leaf block that
1916  * records checksums.
1917  */
1918 struct ext4_dir_entry_tail {
1919 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1920 	__le16	det_rec_len;		/* 12 */
1921 	__u8	det_reserved_zero2;	/* Zero name length */
1922 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1923 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1924 };
1925 
1926 #define EXT4_DIRENT_TAIL(block, blocksize) \
1927 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1928 					((blocksize) - \
1929 					 sizeof(struct ext4_dir_entry_tail))))
1930 
1931 /*
1932  * Ext4 directory file types.  Only the low 3 bits are used.  The
1933  * other bits are reserved for now.
1934  */
1935 #define EXT4_FT_UNKNOWN		0
1936 #define EXT4_FT_REG_FILE	1
1937 #define EXT4_FT_DIR		2
1938 #define EXT4_FT_CHRDEV		3
1939 #define EXT4_FT_BLKDEV		4
1940 #define EXT4_FT_FIFO		5
1941 #define EXT4_FT_SOCK		6
1942 #define EXT4_FT_SYMLINK		7
1943 
1944 #define EXT4_FT_MAX		8
1945 
1946 #define EXT4_FT_DIR_CSUM	0xDE
1947 
1948 /*
1949  * EXT4_DIR_PAD defines the directory entries boundaries
1950  *
1951  * NOTE: It must be a multiple of 4
1952  */
1953 #define EXT4_DIR_PAD			4
1954 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1955 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1956 					 ~EXT4_DIR_ROUND)
1957 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1958 
1959 /*
1960  * If we ever get support for fs block sizes > page_size, we'll need
1961  * to remove the #if statements in the next two functions...
1962  */
1963 static inline unsigned int
1964 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1965 {
1966 	unsigned len = le16_to_cpu(dlen);
1967 
1968 #if (PAGE_SIZE >= 65536)
1969 	if (len == EXT4_MAX_REC_LEN || len == 0)
1970 		return blocksize;
1971 	return (len & 65532) | ((len & 3) << 16);
1972 #else
1973 	return len;
1974 #endif
1975 }
1976 
1977 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1978 {
1979 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1980 		BUG();
1981 #if (PAGE_SIZE >= 65536)
1982 	if (len < 65536)
1983 		return cpu_to_le16(len);
1984 	if (len == blocksize) {
1985 		if (blocksize == 65536)
1986 			return cpu_to_le16(EXT4_MAX_REC_LEN);
1987 		else
1988 			return cpu_to_le16(0);
1989 	}
1990 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1991 #else
1992 	return cpu_to_le16(len);
1993 #endif
1994 }
1995 
1996 /*
1997  * Hash Tree Directory indexing
1998  * (c) Daniel Phillips, 2001
1999  */
2000 
2001 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2002 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2003 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2004 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2005 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2006 
2007 /* Legal values for the dx_root hash_version field: */
2008 
2009 #define DX_HASH_LEGACY			0
2010 #define DX_HASH_HALF_MD4		1
2011 #define DX_HASH_TEA			2
2012 #define DX_HASH_LEGACY_UNSIGNED		3
2013 #define DX_HASH_HALF_MD4_UNSIGNED	4
2014 #define DX_HASH_TEA_UNSIGNED		5
2015 
2016 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2017 			      const void *address, unsigned int length)
2018 {
2019 	struct {
2020 		struct shash_desc shash;
2021 		char ctx[4];
2022 	} desc;
2023 
2024 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2025 
2026 	desc.shash.tfm = sbi->s_chksum_driver;
2027 	desc.shash.flags = 0;
2028 	*(u32 *)desc.ctx = crc;
2029 
2030 	BUG_ON(crypto_shash_update(&desc.shash, address, length));
2031 
2032 	return *(u32 *)desc.ctx;
2033 }
2034 
2035 #ifdef __KERNEL__
2036 
2037 /* hash info structure used by the directory hash */
2038 struct dx_hash_info
2039 {
2040 	u32		hash;
2041 	u32		minor_hash;
2042 	int		hash_version;
2043 	u32		*seed;
2044 };
2045 
2046 
2047 /* 32 and 64 bit signed EOF for dx directories */
2048 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2049 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2050 
2051 
2052 /*
2053  * Control parameters used by ext4_htree_next_block
2054  */
2055 #define HASH_NB_ALWAYS		1
2056 
2057 struct ext4_filename {
2058 	const struct qstr *usr_fname;
2059 	struct fscrypt_str disk_name;
2060 	struct dx_hash_info hinfo;
2061 #ifdef CONFIG_FS_ENCRYPTION
2062 	struct fscrypt_str crypto_buf;
2063 #endif
2064 };
2065 
2066 #define fname_name(p) ((p)->disk_name.name)
2067 #define fname_len(p)  ((p)->disk_name.len)
2068 
2069 /*
2070  * Describe an inode's exact location on disk and in memory
2071  */
2072 struct ext4_iloc
2073 {
2074 	struct buffer_head *bh;
2075 	unsigned long offset;
2076 	ext4_group_t block_group;
2077 };
2078 
2079 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2080 {
2081 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2082 }
2083 
2084 static inline bool ext4_is_quota_file(struct inode *inode)
2085 {
2086 	return IS_NOQUOTA(inode) &&
2087 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2088 }
2089 
2090 /*
2091  * This structure is stuffed into the struct file's private_data field
2092  * for directories.  It is where we put information so that we can do
2093  * readdir operations in hash tree order.
2094  */
2095 struct dir_private_info {
2096 	struct rb_root	root;
2097 	struct rb_node	*curr_node;
2098 	struct fname	*extra_fname;
2099 	loff_t		last_pos;
2100 	__u32		curr_hash;
2101 	__u32		curr_minor_hash;
2102 	__u32		next_hash;
2103 };
2104 
2105 /* calculate the first block number of the group */
2106 static inline ext4_fsblk_t
2107 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2108 {
2109 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2110 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2111 }
2112 
2113 /*
2114  * Special error return code only used by dx_probe() and its callers.
2115  */
2116 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2117 
2118 /* htree levels for ext4 */
2119 #define	EXT4_HTREE_LEVEL_COMPAT	2
2120 #define	EXT4_HTREE_LEVEL	3
2121 
2122 static inline int ext4_dir_htree_level(struct super_block *sb)
2123 {
2124 	return ext4_has_feature_largedir(sb) ?
2125 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2126 }
2127 
2128 /*
2129  * Timeout and state flag for lazy initialization inode thread.
2130  */
2131 #define EXT4_DEF_LI_WAIT_MULT			10
2132 #define EXT4_DEF_LI_MAX_START_DELAY		5
2133 #define EXT4_LAZYINIT_QUIT			0x0001
2134 #define EXT4_LAZYINIT_RUNNING			0x0002
2135 
2136 /*
2137  * Lazy inode table initialization info
2138  */
2139 struct ext4_lazy_init {
2140 	unsigned long		li_state;
2141 	struct list_head	li_request_list;
2142 	struct mutex		li_list_mtx;
2143 };
2144 
2145 struct ext4_li_request {
2146 	struct super_block	*lr_super;
2147 	struct ext4_sb_info	*lr_sbi;
2148 	ext4_group_t		lr_next_group;
2149 	struct list_head	lr_request;
2150 	unsigned long		lr_next_sched;
2151 	unsigned long		lr_timeout;
2152 };
2153 
2154 struct ext4_features {
2155 	struct kobject f_kobj;
2156 	struct completion f_kobj_unregister;
2157 };
2158 
2159 /*
2160  * This structure will be used for multiple mount protection. It will be
2161  * written into the block number saved in the s_mmp_block field in the
2162  * superblock. Programs that check MMP should assume that if
2163  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2164  * to use the filesystem, regardless of how old the timestamp is.
2165  */
2166 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2167 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2168 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2169 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2170 
2171 struct mmp_struct {
2172 	__le32	mmp_magic;		/* Magic number for MMP */
2173 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2174 
2175 	/*
2176 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2177 	 * purposes and do not affect the correctness of the algorithm
2178 	 */
2179 	__le64	mmp_time;		/* Time last updated */
2180 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2181 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2182 
2183 	/*
2184 	 * mmp_check_interval is used to verify if the MMP block has been
2185 	 * updated on the block device. The value is updated based on the
2186 	 * maximum time to write the MMP block during an update cycle.
2187 	 */
2188 	__le16	mmp_check_interval;
2189 
2190 	__le16	mmp_pad1;
2191 	__le32	mmp_pad2[226];
2192 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2193 };
2194 
2195 /* arguments passed to the mmp thread */
2196 struct mmpd_data {
2197 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2198 	struct super_block *sb;  /* super block of the fs */
2199 };
2200 
2201 /*
2202  * Check interval multiplier
2203  * The MMP block is written every update interval and initially checked every
2204  * update interval x the multiplier (the value is then adapted based on the
2205  * write latency). The reason is that writes can be delayed under load and we
2206  * don't want readers to incorrectly assume that the filesystem is no longer
2207  * in use.
2208  */
2209 #define EXT4_MMP_CHECK_MULT		2UL
2210 
2211 /*
2212  * Minimum interval for MMP checking in seconds.
2213  */
2214 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2215 
2216 /*
2217  * Maximum interval for MMP checking in seconds.
2218  */
2219 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2220 
2221 /*
2222  * Function prototypes
2223  */
2224 
2225 /*
2226  * Ok, these declarations are also in <linux/kernel.h> but none of the
2227  * ext4 source programs needs to include it so they are duplicated here.
2228  */
2229 # define NORET_TYPE	/**/
2230 # define ATTRIB_NORET	__attribute__((noreturn))
2231 # define NORET_AND	noreturn,
2232 
2233 /* bitmap.c */
2234 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2235 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2236 				struct ext4_group_desc *gdp,
2237 				struct buffer_head *bh, int sz);
2238 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2239 				  struct ext4_group_desc *gdp,
2240 				  struct buffer_head *bh, int sz);
2241 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2242 				struct ext4_group_desc *gdp,
2243 				struct buffer_head *bh);
2244 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2245 				  struct ext4_group_desc *gdp,
2246 				  struct buffer_head *bh);
2247 
2248 /* balloc.c */
2249 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2250 					 ext4_fsblk_t blocknr,
2251 					 ext4_group_t *blockgrpp,
2252 					 ext4_grpblk_t *offsetp);
2253 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2254 					  ext4_fsblk_t block);
2255 
2256 extern unsigned int ext4_block_group(struct super_block *sb,
2257 			ext4_fsblk_t blocknr);
2258 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2259 			ext4_fsblk_t blocknr);
2260 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2261 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2262 			ext4_group_t group);
2263 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2264 					 ext4_fsblk_t goal,
2265 					 unsigned int flags,
2266 					 unsigned long *count,
2267 					 int *errp);
2268 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2269 				    s64 nclusters, unsigned int flags);
2270 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2271 extern void ext4_check_blocks_bitmap(struct super_block *);
2272 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2273 						    ext4_group_t block_group,
2274 						    struct buffer_head ** bh);
2275 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2276 
2277 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2278 						ext4_group_t block_group);
2279 extern int ext4_wait_block_bitmap(struct super_block *sb,
2280 				  ext4_group_t block_group,
2281 				  struct buffer_head *bh);
2282 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2283 						  ext4_group_t block_group);
2284 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2285 					      ext4_group_t block_group,
2286 					      struct ext4_group_desc *gdp);
2287 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2288 
2289 #ifdef CONFIG_FS_ENCRYPTION
2290 static inline int ext4_fname_setup_filename(struct inode *dir,
2291 			const struct qstr *iname,
2292 			int lookup, struct ext4_filename *fname)
2293 {
2294 	struct fscrypt_name name;
2295 	int err;
2296 
2297 	memset(fname, 0, sizeof(struct ext4_filename));
2298 
2299 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2300 
2301 	fname->usr_fname = name.usr_fname;
2302 	fname->disk_name = name.disk_name;
2303 	fname->hinfo.hash = name.hash;
2304 	fname->hinfo.minor_hash = name.minor_hash;
2305 	fname->crypto_buf = name.crypto_buf;
2306 	return err;
2307 }
2308 
2309 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2310 {
2311 	struct fscrypt_name name;
2312 
2313 	name.crypto_buf = fname->crypto_buf;
2314 	fscrypt_free_filename(&name);
2315 
2316 	fname->crypto_buf.name = NULL;
2317 	fname->usr_fname = NULL;
2318 	fname->disk_name.name = NULL;
2319 }
2320 #else
2321 static inline int ext4_fname_setup_filename(struct inode *dir,
2322 		const struct qstr *iname,
2323 		int lookup, struct ext4_filename *fname)
2324 {
2325 	fname->usr_fname = iname;
2326 	fname->disk_name.name = (unsigned char *) iname->name;
2327 	fname->disk_name.len = iname->len;
2328 	return 0;
2329 }
2330 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2331 
2332 #endif
2333 
2334 /* dir.c */
2335 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2336 				  struct file *,
2337 				  struct ext4_dir_entry_2 *,
2338 				  struct buffer_head *, char *, int,
2339 				  unsigned int);
2340 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2341 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2342 					(de), (bh), (buf), (size), (offset)))
2343 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2344 				__u32 minor_hash,
2345 				struct ext4_dir_entry_2 *dirent,
2346 				struct fscrypt_str *ent_name);
2347 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2348 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2349 			     struct buffer_head *bh,
2350 			     void *buf, int buf_size,
2351 			     struct ext4_filename *fname,
2352 			     struct ext4_dir_entry_2 **dest_de);
2353 void ext4_insert_dentry(struct inode *inode,
2354 			struct ext4_dir_entry_2 *de,
2355 			int buf_size,
2356 			struct ext4_filename *fname);
2357 static inline void ext4_update_dx_flag(struct inode *inode)
2358 {
2359 	if (!ext4_has_feature_dir_index(inode->i_sb))
2360 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2361 }
2362 static const unsigned char ext4_filetype_table[] = {
2363 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2364 };
2365 
2366 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2367 {
2368 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2369 		return DT_UNKNOWN;
2370 
2371 	return ext4_filetype_table[filetype];
2372 }
2373 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2374 			     void *buf, int buf_size);
2375 
2376 /* fsync.c */
2377 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2378 
2379 /* hash.c */
2380 extern int ext4fs_dirhash(const char *name, int len, struct
2381 			  dx_hash_info *hinfo);
2382 
2383 /* ialloc.c */
2384 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2385 				      const struct qstr *qstr, __u32 goal,
2386 				      uid_t *owner, __u32 i_flags,
2387 				      int handle_type, unsigned int line_no,
2388 				      int nblocks);
2389 
2390 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2391 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2392 			 i_flags, 0, 0, 0)
2393 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2394 				    type, nblocks)		    \
2395 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2396 			 0, (type), __LINE__, (nblocks))
2397 
2398 
2399 extern void ext4_free_inode(handle_t *, struct inode *);
2400 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2401 extern unsigned long ext4_count_free_inodes(struct super_block *);
2402 extern unsigned long ext4_count_dirs(struct super_block *);
2403 extern void ext4_check_inodes_bitmap(struct super_block *);
2404 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2405 extern int ext4_init_inode_table(struct super_block *sb,
2406 				 ext4_group_t group, int barrier);
2407 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2408 
2409 /* mballoc.c */
2410 extern const struct seq_operations ext4_mb_seq_groups_ops;
2411 extern long ext4_mb_stats;
2412 extern long ext4_mb_max_to_scan;
2413 extern int ext4_mb_init(struct super_block *);
2414 extern int ext4_mb_release(struct super_block *);
2415 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2416 				struct ext4_allocation_request *, int *);
2417 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2418 extern void ext4_discard_preallocations(struct inode *);
2419 extern int __init ext4_init_mballoc(void);
2420 extern void ext4_exit_mballoc(void);
2421 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2422 			     struct buffer_head *bh, ext4_fsblk_t block,
2423 			     unsigned long count, int flags);
2424 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2425 				   ext4_group_t ngroups);
2426 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2427 		ext4_group_t i, struct ext4_group_desc *desc);
2428 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2429 				ext4_fsblk_t block, unsigned long count);
2430 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2431 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2432 
2433 /* inode.c */
2434 int ext4_inode_is_fast_symlink(struct inode *inode);
2435 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2436 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2437 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2438 		     bool wait, struct buffer_head **bhs);
2439 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2440 			     struct buffer_head *bh_result, int create);
2441 int ext4_get_block(struct inode *inode, sector_t iblock,
2442 		   struct buffer_head *bh_result, int create);
2443 int ext4_dio_get_block(struct inode *inode, sector_t iblock,
2444 		       struct buffer_head *bh_result, int create);
2445 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2446 			   struct buffer_head *bh, int create);
2447 int ext4_walk_page_buffers(handle_t *handle,
2448 			   struct buffer_head *head,
2449 			   unsigned from,
2450 			   unsigned to,
2451 			   int *partial,
2452 			   int (*fn)(handle_t *handle,
2453 				     struct buffer_head *bh));
2454 int do_journal_get_write_access(handle_t *handle,
2455 				struct buffer_head *bh);
2456 #define FALL_BACK_TO_NONDELALLOC 1
2457 #define CONVERT_INLINE_DATA	 2
2458 
2459 typedef enum {
2460 	EXT4_IGET_NORMAL =	0,
2461 	EXT4_IGET_SPECIAL =	0x0001, /* OK to iget a system inode */
2462 	EXT4_IGET_HANDLE = 	0x0002	/* Inode # is from a handle */
2463 } ext4_iget_flags;
2464 
2465 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2466 				 ext4_iget_flags flags, const char *function,
2467 				 unsigned int line);
2468 
2469 #define ext4_iget(sb, ino, flags) \
2470 	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2471 
2472 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2473 extern int  ext4_setattr(struct dentry *, struct iattr *);
2474 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2475 extern void ext4_evict_inode(struct inode *);
2476 extern void ext4_clear_inode(struct inode *);
2477 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2478 extern int  ext4_sync_inode(handle_t *, struct inode *);
2479 extern void ext4_dirty_inode(struct inode *, int);
2480 extern int ext4_change_inode_journal_flag(struct inode *, int);
2481 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2482 extern int ext4_inode_attach_jinode(struct inode *inode);
2483 extern int ext4_can_truncate(struct inode *inode);
2484 extern int ext4_truncate(struct inode *);
2485 extern int ext4_break_layouts(struct inode *);
2486 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2487 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2488 extern void ext4_set_inode_flags(struct inode *);
2489 extern int ext4_alloc_da_blocks(struct inode *inode);
2490 extern void ext4_set_aops(struct inode *inode);
2491 extern int ext4_writepage_trans_blocks(struct inode *);
2492 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2493 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2494 			     loff_t lstart, loff_t lend);
2495 extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf);
2496 extern vm_fault_t ext4_filemap_fault(struct vm_fault *vmf);
2497 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2498 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2499 extern void ext4_da_release_space(struct inode *inode, int to_free);
2500 extern void ext4_da_update_reserve_space(struct inode *inode,
2501 					int used, int quota_claim);
2502 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2503 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2504 
2505 /* indirect.c */
2506 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2507 				struct ext4_map_blocks *map, int flags);
2508 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2509 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2510 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2511 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2512 				 ext4_lblk_t start, ext4_lblk_t end);
2513 
2514 /* ioctl.c */
2515 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2516 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2517 
2518 /* migrate.c */
2519 extern int ext4_ext_migrate(struct inode *);
2520 extern int ext4_ind_migrate(struct inode *inode);
2521 
2522 /* namei.c */
2523 extern int ext4_dirent_csum_verify(struct inode *inode,
2524 				   struct ext4_dir_entry *dirent);
2525 extern int ext4_orphan_add(handle_t *, struct inode *);
2526 extern int ext4_orphan_del(handle_t *, struct inode *);
2527 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2528 				__u32 start_minor_hash, __u32 *next_hash);
2529 extern int ext4_search_dir(struct buffer_head *bh,
2530 			   char *search_buf,
2531 			   int buf_size,
2532 			   struct inode *dir,
2533 			   struct ext4_filename *fname,
2534 			   unsigned int offset,
2535 			   struct ext4_dir_entry_2 **res_dir);
2536 extern int ext4_generic_delete_entry(handle_t *handle,
2537 				     struct inode *dir,
2538 				     struct ext4_dir_entry_2 *de_del,
2539 				     struct buffer_head *bh,
2540 				     void *entry_buf,
2541 				     int buf_size,
2542 				     int csum_size);
2543 extern bool ext4_empty_dir(struct inode *inode);
2544 
2545 /* resize.c */
2546 extern int ext4_group_add(struct super_block *sb,
2547 				struct ext4_new_group_data *input);
2548 extern int ext4_group_extend(struct super_block *sb,
2549 				struct ext4_super_block *es,
2550 				ext4_fsblk_t n_blocks_count);
2551 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2552 
2553 /* super.c */
2554 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
2555 					 sector_t block, int op_flags);
2556 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2557 extern int ext4_calculate_overhead(struct super_block *sb);
2558 extern void ext4_superblock_csum_set(struct super_block *sb);
2559 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2560 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2561 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2562 				    ext4_group_t ngroup);
2563 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2564 				     char nbuf[16]);
2565 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
2566 					     ext4_group_t block_group,
2567 					     unsigned int flags);
2568 
2569 extern __printf(4, 5)
2570 void __ext4_error(struct super_block *, const char *, unsigned int,
2571 		  const char *, ...);
2572 extern __printf(5, 6)
2573 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2574 		      const char *, ...);
2575 extern __printf(5, 6)
2576 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2577 		     const char *, ...);
2578 extern void __ext4_std_error(struct super_block *, const char *,
2579 			     unsigned int, int);
2580 extern __printf(4, 5)
2581 void __ext4_abort(struct super_block *, const char *, unsigned int,
2582 		  const char *, ...);
2583 extern __printf(4, 5)
2584 void __ext4_warning(struct super_block *, const char *, unsigned int,
2585 		    const char *, ...);
2586 extern __printf(4, 5)
2587 void __ext4_warning_inode(const struct inode *inode, const char *function,
2588 			  unsigned int line, const char *fmt, ...);
2589 extern __printf(3, 4)
2590 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2591 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2592 			   const char *, unsigned int, const char *);
2593 extern __printf(7, 8)
2594 void __ext4_grp_locked_error(const char *, unsigned int,
2595 			     struct super_block *, ext4_group_t,
2596 			     unsigned long, ext4_fsblk_t,
2597 			     const char *, ...);
2598 
2599 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2600 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2601 
2602 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
2603 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2604 
2605 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2606 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2607 
2608 #ifdef CONFIG_PRINTK
2609 
2610 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2611 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2612 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2613 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2614 #define ext4_error(sb, fmt, ...)					\
2615 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2616 #define ext4_abort(sb, fmt, ...)					\
2617 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2618 #define ext4_warning(sb, fmt, ...)					\
2619 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2620 #define ext4_warning_inode(inode, fmt, ...)				\
2621 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2622 #define ext4_msg(sb, level, fmt, ...)				\
2623 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2624 #define dump_mmp_msg(sb, mmp, msg)					\
2625 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2626 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2627 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2628 				fmt, ##__VA_ARGS__)
2629 
2630 #else
2631 
2632 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2633 do {									\
2634 	no_printk(fmt, ##__VA_ARGS__);					\
2635 	__ext4_error_inode(inode, "", 0, block, " ");			\
2636 } while (0)
2637 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2638 do {									\
2639 	no_printk(fmt, ##__VA_ARGS__);					\
2640 	__ext4_error_file(file, "", 0, block, " ");			\
2641 } while (0)
2642 #define ext4_error(sb, fmt, ...)					\
2643 do {									\
2644 	no_printk(fmt, ##__VA_ARGS__);					\
2645 	__ext4_error(sb, "", 0, " ");					\
2646 } while (0)
2647 #define ext4_abort(sb, fmt, ...)					\
2648 do {									\
2649 	no_printk(fmt, ##__VA_ARGS__);					\
2650 	__ext4_abort(sb, "", 0, " ");					\
2651 } while (0)
2652 #define ext4_warning(sb, fmt, ...)					\
2653 do {									\
2654 	no_printk(fmt, ##__VA_ARGS__);					\
2655 	__ext4_warning(sb, "", 0, " ");					\
2656 } while (0)
2657 #define ext4_warning_inode(inode, fmt, ...)				\
2658 do {									\
2659 	no_printk(fmt, ##__VA_ARGS__);					\
2660 	__ext4_warning_inode(inode, "", 0, " ");			\
2661 } while (0)
2662 #define ext4_msg(sb, level, fmt, ...)					\
2663 do {									\
2664 	no_printk(fmt, ##__VA_ARGS__);					\
2665 	__ext4_msg(sb, "", " ");					\
2666 } while (0)
2667 #define dump_mmp_msg(sb, mmp, msg)					\
2668 	__dump_mmp_msg(sb, mmp, "", 0, "")
2669 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2670 do {									\
2671 	no_printk(fmt, ##__VA_ARGS__);				\
2672 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2673 } while (0)
2674 
2675 #endif
2676 
2677 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2678 					__u32 compat);
2679 extern int ext4_update_rocompat_feature(handle_t *handle,
2680 					struct super_block *sb,	__u32 rocompat);
2681 extern int ext4_update_incompat_feature(handle_t *handle,
2682 					struct super_block *sb,	__u32 incompat);
2683 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2684 				      struct ext4_group_desc *bg);
2685 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2686 				      struct ext4_group_desc *bg);
2687 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2688 				     struct ext4_group_desc *bg);
2689 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2690 				      struct ext4_group_desc *bg);
2691 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2692 				 struct ext4_group_desc *bg);
2693 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2694 				struct ext4_group_desc *bg);
2695 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2696 				   struct ext4_group_desc *bg);
2697 extern void ext4_block_bitmap_set(struct super_block *sb,
2698 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2699 extern void ext4_inode_bitmap_set(struct super_block *sb,
2700 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2701 extern void ext4_inode_table_set(struct super_block *sb,
2702 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2703 extern void ext4_free_group_clusters_set(struct super_block *sb,
2704 					 struct ext4_group_desc *bg,
2705 					 __u32 count);
2706 extern void ext4_free_inodes_set(struct super_block *sb,
2707 				struct ext4_group_desc *bg, __u32 count);
2708 extern void ext4_used_dirs_set(struct super_block *sb,
2709 				struct ext4_group_desc *bg, __u32 count);
2710 extern void ext4_itable_unused_set(struct super_block *sb,
2711 				   struct ext4_group_desc *bg, __u32 count);
2712 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2713 				       struct ext4_group_desc *gdp);
2714 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2715 				     struct ext4_group_desc *gdp);
2716 extern int ext4_register_li_request(struct super_block *sb,
2717 				    ext4_group_t first_not_zeroed);
2718 
2719 static inline int ext4_has_metadata_csum(struct super_block *sb)
2720 {
2721 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2722 		     !EXT4_SB(sb)->s_chksum_driver);
2723 
2724 	return ext4_has_feature_metadata_csum(sb) &&
2725 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
2726 }
2727 
2728 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2729 {
2730 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
2731 }
2732 
2733 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2734 {
2735 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2736 		le32_to_cpu(es->s_blocks_count_lo);
2737 }
2738 
2739 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2740 {
2741 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2742 		le32_to_cpu(es->s_r_blocks_count_lo);
2743 }
2744 
2745 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2746 {
2747 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2748 		le32_to_cpu(es->s_free_blocks_count_lo);
2749 }
2750 
2751 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2752 					 ext4_fsblk_t blk)
2753 {
2754 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2755 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2756 }
2757 
2758 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2759 					      ext4_fsblk_t blk)
2760 {
2761 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2762 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2763 }
2764 
2765 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2766 					   ext4_fsblk_t blk)
2767 {
2768 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2769 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2770 }
2771 
2772 static inline loff_t ext4_isize(struct super_block *sb,
2773 				struct ext4_inode *raw_inode)
2774 {
2775 	if (ext4_has_feature_largedir(sb) ||
2776 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2777 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2778 			le32_to_cpu(raw_inode->i_size_lo);
2779 
2780 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2781 }
2782 
2783 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2784 {
2785 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2786 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2787 }
2788 
2789 static inline
2790 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2791 					    ext4_group_t group)
2792 {
2793 	 struct ext4_group_info ***grp_info;
2794 	 long indexv, indexh;
2795 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2796 	 grp_info = EXT4_SB(sb)->s_group_info;
2797 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2798 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2799 	 return grp_info[indexv][indexh];
2800 }
2801 
2802 /*
2803  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2804  * the locking protocol documented in the comments of ext4_group_add()
2805  * in resize.c
2806  */
2807 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2808 {
2809 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2810 
2811 	smp_rmb();
2812 	return ngroups;
2813 }
2814 
2815 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2816 					     ext4_group_t block_group)
2817 {
2818 	return block_group >> sbi->s_log_groups_per_flex;
2819 }
2820 
2821 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2822 {
2823 	return 1 << sbi->s_log_groups_per_flex;
2824 }
2825 
2826 #define ext4_std_error(sb, errno)				\
2827 do {								\
2828 	if ((errno))						\
2829 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2830 } while (0)
2831 
2832 #ifdef CONFIG_SMP
2833 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2834  * counters. So we need to make sure we have free clusters more
2835  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2836  */
2837 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2838 #else
2839 #define EXT4_FREECLUSTERS_WATERMARK 0
2840 #endif
2841 
2842 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2843 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2844 {
2845 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2846 		     !inode_is_locked(inode));
2847 	down_write(&EXT4_I(inode)->i_data_sem);
2848 	if (newsize > EXT4_I(inode)->i_disksize)
2849 		EXT4_I(inode)->i_disksize = newsize;
2850 	up_write(&EXT4_I(inode)->i_data_sem);
2851 }
2852 
2853 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2854 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2855 {
2856 	int changed = 0;
2857 
2858 	if (newsize > inode->i_size) {
2859 		i_size_write(inode, newsize);
2860 		changed = 1;
2861 	}
2862 	if (newsize > EXT4_I(inode)->i_disksize) {
2863 		ext4_update_i_disksize(inode, newsize);
2864 		changed |= 2;
2865 	}
2866 	return changed;
2867 }
2868 
2869 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2870 				      loff_t len);
2871 
2872 struct ext4_group_info {
2873 	unsigned long   bb_state;
2874 	struct rb_root  bb_free_root;
2875 	ext4_grpblk_t	bb_first_free;	/* first free block */
2876 	ext4_grpblk_t	bb_free;	/* total free blocks */
2877 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2878 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2879 	struct          list_head bb_prealloc_list;
2880 #ifdef DOUBLE_CHECK
2881 	void            *bb_bitmap;
2882 #endif
2883 	struct rw_semaphore alloc_sem;
2884 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2885 					 * regions, index is order.
2886 					 * bb_counters[3] = 5 means
2887 					 * 5 free 8-block regions. */
2888 };
2889 
2890 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2891 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2892 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2893 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2894 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT		\
2895 	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
2896 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT		\
2897 	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
2898 
2899 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2900 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2901 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2902 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2903 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2904 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2905 
2906 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2907 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2908 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2909 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2910 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2911 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2912 
2913 #define EXT4_MAX_CONTENTION		8
2914 #define EXT4_CONTENTION_THRESHOLD	2
2915 
2916 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2917 					      ext4_group_t group)
2918 {
2919 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2920 }
2921 
2922 /*
2923  * Returns true if the filesystem is busy enough that attempts to
2924  * access the block group locks has run into contention.
2925  */
2926 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2927 {
2928 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2929 }
2930 
2931 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2932 {
2933 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2934 	if (spin_trylock(lock))
2935 		/*
2936 		 * We're able to grab the lock right away, so drop the
2937 		 * lock contention counter.
2938 		 */
2939 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2940 	else {
2941 		/*
2942 		 * The lock is busy, so bump the contention counter,
2943 		 * and then wait on the spin lock.
2944 		 */
2945 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2946 				  EXT4_MAX_CONTENTION);
2947 		spin_lock(lock);
2948 	}
2949 }
2950 
2951 static inline void ext4_unlock_group(struct super_block *sb,
2952 					ext4_group_t group)
2953 {
2954 	spin_unlock(ext4_group_lock_ptr(sb, group));
2955 }
2956 
2957 /*
2958  * Block validity checking
2959  */
2960 #define ext4_check_indirect_blockref(inode, bh)				\
2961 	ext4_check_blockref(__func__, __LINE__, inode,			\
2962 			    (__le32 *)(bh)->b_data,			\
2963 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2964 
2965 #define ext4_ind_check_inode(inode)					\
2966 	ext4_check_blockref(__func__, __LINE__, inode,			\
2967 			    EXT4_I(inode)->i_data,			\
2968 			    EXT4_NDIR_BLOCKS)
2969 
2970 /*
2971  * Inodes and files operations
2972  */
2973 
2974 /* dir.c */
2975 extern const struct file_operations ext4_dir_operations;
2976 
2977 /* file.c */
2978 extern const struct inode_operations ext4_file_inode_operations;
2979 extern const struct file_operations ext4_file_operations;
2980 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2981 
2982 /* inline.c */
2983 extern int ext4_get_max_inline_size(struct inode *inode);
2984 extern int ext4_find_inline_data_nolock(struct inode *inode);
2985 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2986 				 unsigned int len);
2987 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2988 
2989 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2990 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2991 					 struct inode *inode,
2992 					 loff_t pos, unsigned len,
2993 					 unsigned flags,
2994 					 struct page **pagep);
2995 extern int ext4_write_inline_data_end(struct inode *inode,
2996 				      loff_t pos, unsigned len,
2997 				      unsigned copied,
2998 				      struct page *page);
2999 extern struct buffer_head *
3000 ext4_journalled_write_inline_data(struct inode *inode,
3001 				  unsigned len,
3002 				  struct page *page);
3003 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3004 					   struct inode *inode,
3005 					   loff_t pos, unsigned len,
3006 					   unsigned flags,
3007 					   struct page **pagep,
3008 					   void **fsdata);
3009 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3010 					 unsigned len, unsigned copied,
3011 					 struct page *page);
3012 extern int ext4_try_add_inline_entry(handle_t *handle,
3013 				     struct ext4_filename *fname,
3014 				     struct inode *dir, struct inode *inode);
3015 extern int ext4_try_create_inline_dir(handle_t *handle,
3016 				      struct inode *parent,
3017 				      struct inode *inode);
3018 extern int ext4_read_inline_dir(struct file *filp,
3019 				struct dir_context *ctx,
3020 				int *has_inline_data);
3021 extern int htree_inlinedir_to_tree(struct file *dir_file,
3022 				   struct inode *dir, ext4_lblk_t block,
3023 				   struct dx_hash_info *hinfo,
3024 				   __u32 start_hash, __u32 start_minor_hash,
3025 				   int *has_inline_data);
3026 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3027 					struct ext4_filename *fname,
3028 					struct ext4_dir_entry_2 **res_dir,
3029 					int *has_inline_data);
3030 extern int ext4_delete_inline_entry(handle_t *handle,
3031 				    struct inode *dir,
3032 				    struct ext4_dir_entry_2 *de_del,
3033 				    struct buffer_head *bh,
3034 				    int *has_inline_data);
3035 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3036 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3037 					struct ext4_dir_entry_2 **parent_de,
3038 					int *retval);
3039 extern int ext4_inline_data_fiemap(struct inode *inode,
3040 				   struct fiemap_extent_info *fieinfo,
3041 				   int *has_inline, __u64 start, __u64 len);
3042 
3043 struct iomap;
3044 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3045 
3046 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3047 
3048 extern int ext4_convert_inline_data(struct inode *inode);
3049 
3050 static inline int ext4_has_inline_data(struct inode *inode)
3051 {
3052 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3053 	       EXT4_I(inode)->i_inline_off;
3054 }
3055 
3056 /* namei.c */
3057 extern const struct inode_operations ext4_dir_inode_operations;
3058 extern const struct inode_operations ext4_special_inode_operations;
3059 extern struct dentry *ext4_get_parent(struct dentry *child);
3060 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3061 				 struct ext4_dir_entry_2 *de,
3062 				 int blocksize, int csum_size,
3063 				 unsigned int parent_ino, int dotdot_real_len);
3064 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
3065 				   unsigned int blocksize);
3066 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
3067 					 struct inode *inode,
3068 					 struct buffer_head *bh);
3069 #define S_SHIFT 12
3070 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3071 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3072 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3073 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3074 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3075 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3076 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3077 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3078 };
3079 
3080 static inline void ext4_set_de_type(struct super_block *sb,
3081 				struct ext4_dir_entry_2 *de,
3082 				umode_t mode) {
3083 	if (ext4_has_feature_filetype(sb))
3084 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3085 }
3086 
3087 /* readpages.c */
3088 extern int ext4_mpage_readpages(struct address_space *mapping,
3089 				struct list_head *pages, struct page *page,
3090 				unsigned nr_pages, bool is_readahead);
3091 
3092 /* symlink.c */
3093 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3094 extern const struct inode_operations ext4_symlink_inode_operations;
3095 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3096 
3097 /* sysfs.c */
3098 extern int ext4_register_sysfs(struct super_block *sb);
3099 extern void ext4_unregister_sysfs(struct super_block *sb);
3100 extern int __init ext4_init_sysfs(void);
3101 extern void ext4_exit_sysfs(void);
3102 
3103 /* block_validity */
3104 extern void ext4_release_system_zone(struct super_block *sb);
3105 extern int ext4_setup_system_zone(struct super_block *sb);
3106 extern int __init ext4_init_system_zone(void);
3107 extern void ext4_exit_system_zone(void);
3108 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3109 				 ext4_fsblk_t start_blk,
3110 				 unsigned int count);
3111 extern int ext4_check_blockref(const char *, unsigned int,
3112 			       struct inode *, __le32 *, unsigned int);
3113 
3114 /* extents.c */
3115 struct ext4_ext_path;
3116 struct ext4_extent;
3117 
3118 /*
3119  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3120  * __le32.
3121  */
3122 #define EXT_MAX_BLOCKS	0xffffffff
3123 
3124 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
3125 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
3126 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3127 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3128 			       struct ext4_map_blocks *map, int flags);
3129 extern int ext4_ext_truncate(handle_t *, struct inode *);
3130 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3131 				 ext4_lblk_t end);
3132 extern void ext4_ext_init(struct super_block *);
3133 extern void ext4_ext_release(struct super_block *);
3134 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3135 			  loff_t len);
3136 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3137 					  loff_t offset, ssize_t len);
3138 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3139 			   struct ext4_map_blocks *map, int flags);
3140 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
3141 					 ext4_lblk_t lblocks);
3142 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3143 						   int num,
3144 						   struct ext4_ext_path *path);
3145 extern int ext4_can_extents_be_merged(struct inode *inode,
3146 				      struct ext4_extent *ex1,
3147 				      struct ext4_extent *ex2);
3148 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3149 				  struct ext4_ext_path **,
3150 				  struct ext4_extent *, int);
3151 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3152 					      struct ext4_ext_path **,
3153 					      int flags);
3154 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3155 extern int ext4_ext_check_inode(struct inode *inode);
3156 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3157 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3158 			__u64 start, __u64 len);
3159 extern int ext4_ext_precache(struct inode *inode);
3160 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
3161 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
3162 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3163 				struct inode *inode2, ext4_lblk_t lblk1,
3164 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3165 			     int mark_unwritten,int *err);
3166 extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
3167 
3168 /* move_extent.c */
3169 extern void ext4_double_down_write_data_sem(struct inode *first,
3170 					    struct inode *second);
3171 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3172 					  struct inode *donor_inode);
3173 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3174 			     __u64 start_orig, __u64 start_donor,
3175 			     __u64 len, __u64 *moved_len);
3176 
3177 /* page-io.c */
3178 extern int __init ext4_init_pageio(void);
3179 extern void ext4_exit_pageio(void);
3180 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3181 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3182 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3183 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3184 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3185 				struct writeback_control *wbc);
3186 extern void ext4_end_io_rsv_work(struct work_struct *work);
3187 extern void ext4_io_submit(struct ext4_io_submit *io);
3188 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3189 			       struct page *page,
3190 			       int len,
3191 			       struct writeback_control *wbc,
3192 			       bool keep_towrite);
3193 
3194 /* mmp.c */
3195 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3196 
3197 /*
3198  * Add new method to test whether block and inode bitmaps are properly
3199  * initialized. With uninit_bg reading the block from disk is not enough
3200  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3201  */
3202 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3203 
3204 static inline int bitmap_uptodate(struct buffer_head *bh)
3205 {
3206 	return (buffer_uptodate(bh) &&
3207 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3208 }
3209 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3210 {
3211 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3212 }
3213 
3214 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3215 
3216 /* For ioend & aio unwritten conversion wait queues */
3217 #define EXT4_WQ_HASH_SZ		37
3218 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3219 					    EXT4_WQ_HASH_SZ])
3220 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3221 
3222 extern int ext4_resize_begin(struct super_block *sb);
3223 extern void ext4_resize_end(struct super_block *sb);
3224 
3225 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3226 					      struct ext4_io_end *io_end)
3227 {
3228 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3229 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3230 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3231 	}
3232 }
3233 
3234 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3235 {
3236 	struct inode *inode = io_end->inode;
3237 
3238 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3239 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3240 		/* Wake up anyone waiting on unwritten extent conversion */
3241 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3242 			wake_up_all(ext4_ioend_wq(inode));
3243 	}
3244 }
3245 
3246 extern const struct iomap_ops ext4_iomap_ops;
3247 
3248 #endif	/* __KERNEL__ */
3249 
3250 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3251 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3252 
3253 #endif	/* _EXT4_H */
3254