xref: /openbmc/linux/fs/ext4/ext4.h (revision aac5987a)
1 /*
2  *  ext4.h
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/include/linux/minix_fs.h
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  */
15 
16 #ifndef _EXT4_H
17 #define _EXT4_H
18 
19 #include <linux/types.h>
20 #include <linux/blkdev.h>
21 #include <linux/magic.h>
22 #include <linux/jbd2.h>
23 #include <linux/quota.h>
24 #include <linux/rwsem.h>
25 #include <linux/rbtree.h>
26 #include <linux/seqlock.h>
27 #include <linux/mutex.h>
28 #include <linux/timer.h>
29 #include <linux/version.h>
30 #include <linux/wait.h>
31 #include <linux/sched/signal.h>
32 #include <linux/blockgroup_lock.h>
33 #include <linux/percpu_counter.h>
34 #include <linux/ratelimit.h>
35 #include <crypto/hash.h>
36 #ifdef CONFIG_EXT4_FS_ENCRYPTION
37 #include <linux/fscrypt_supp.h>
38 #else
39 #include <linux/fscrypt_notsupp.h>
40 #endif
41 #include <linux/falloc.h>
42 #include <linux/percpu-rwsem.h>
43 #ifdef __KERNEL__
44 #include <linux/compat.h>
45 #endif
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 /* Mask out flags that are inappropriate for the given type of inode. */
429 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
430 {
431 	if (S_ISDIR(mode))
432 		return flags;
433 	else if (S_ISREG(mode))
434 		return flags & EXT4_REG_FLMASK;
435 	else
436 		return flags & EXT4_OTHER_FLMASK;
437 }
438 
439 /*
440  * Inode flags used for atomic set/get
441  */
442 enum {
443 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
444 	EXT4_INODE_UNRM		= 1,	/* Undelete */
445 	EXT4_INODE_COMPR	= 2,	/* Compress file */
446 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
447 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
448 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
449 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
450 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
451 /* Reserved for compression usage... */
452 	EXT4_INODE_DIRTY	= 8,
453 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
454 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
455 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
456 /* End compression flags --- maybe not all used */
457 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
458 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
459 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
460 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
461 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
462 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
463 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
464 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
465 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
466 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
467 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
468 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
469 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
470 };
471 
472 /*
473  * Since it's pretty easy to mix up bit numbers and hex values, we use a
474  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
475  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
476  * any extra space in the compiled kernel image, otherwise, the build will fail.
477  * It's important that these values are the same, since we are using
478  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
479  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
480  * values found in ext2, ext3 and ext4 filesystems, and of course the values
481  * defined in e2fsprogs.
482  *
483  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
484  */
485 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
486 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
487 
488 static inline void ext4_check_flag_values(void)
489 {
490 	CHECK_FLAG_VALUE(SECRM);
491 	CHECK_FLAG_VALUE(UNRM);
492 	CHECK_FLAG_VALUE(COMPR);
493 	CHECK_FLAG_VALUE(SYNC);
494 	CHECK_FLAG_VALUE(IMMUTABLE);
495 	CHECK_FLAG_VALUE(APPEND);
496 	CHECK_FLAG_VALUE(NODUMP);
497 	CHECK_FLAG_VALUE(NOATIME);
498 	CHECK_FLAG_VALUE(DIRTY);
499 	CHECK_FLAG_VALUE(COMPRBLK);
500 	CHECK_FLAG_VALUE(NOCOMPR);
501 	CHECK_FLAG_VALUE(ENCRYPT);
502 	CHECK_FLAG_VALUE(INDEX);
503 	CHECK_FLAG_VALUE(IMAGIC);
504 	CHECK_FLAG_VALUE(JOURNAL_DATA);
505 	CHECK_FLAG_VALUE(NOTAIL);
506 	CHECK_FLAG_VALUE(DIRSYNC);
507 	CHECK_FLAG_VALUE(TOPDIR);
508 	CHECK_FLAG_VALUE(HUGE_FILE);
509 	CHECK_FLAG_VALUE(EXTENTS);
510 	CHECK_FLAG_VALUE(EA_INODE);
511 	CHECK_FLAG_VALUE(EOFBLOCKS);
512 	CHECK_FLAG_VALUE(INLINE_DATA);
513 	CHECK_FLAG_VALUE(PROJINHERIT);
514 	CHECK_FLAG_VALUE(RESERVED);
515 }
516 
517 /* Used to pass group descriptor data when online resize is done */
518 struct ext4_new_group_input {
519 	__u32 group;		/* Group number for this data */
520 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
521 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
522 	__u64 inode_table;	/* Absolute block number of inode table start */
523 	__u32 blocks_count;	/* Total number of blocks in this group */
524 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
525 	__u16 unused;
526 };
527 
528 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
529 struct compat_ext4_new_group_input {
530 	u32 group;
531 	compat_u64 block_bitmap;
532 	compat_u64 inode_bitmap;
533 	compat_u64 inode_table;
534 	u32 blocks_count;
535 	u16 reserved_blocks;
536 	u16 unused;
537 };
538 #endif
539 
540 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
541 struct ext4_new_group_data {
542 	__u32 group;
543 	__u64 block_bitmap;
544 	__u64 inode_bitmap;
545 	__u64 inode_table;
546 	__u32 blocks_count;
547 	__u16 reserved_blocks;
548 	__u16 unused;
549 	__u32 free_blocks_count;
550 };
551 
552 /* Indexes used to index group tables in ext4_new_group_data */
553 enum {
554 	BLOCK_BITMAP = 0,	/* block bitmap */
555 	INODE_BITMAP,		/* inode bitmap */
556 	INODE_TABLE,		/* inode tables */
557 	GROUP_TABLE_COUNT,
558 };
559 
560 /*
561  * Flags used by ext4_map_blocks()
562  */
563 	/* Allocate any needed blocks and/or convert an unwritten
564 	   extent to be an initialized ext4 */
565 #define EXT4_GET_BLOCKS_CREATE			0x0001
566 	/* Request the creation of an unwritten extent */
567 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
568 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
569 						 EXT4_GET_BLOCKS_CREATE)
570 	/* Caller is from the delayed allocation writeout path
571 	 * finally doing the actual allocation of delayed blocks */
572 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
573 	/* caller is from the direct IO path, request to creation of an
574 	unwritten extents if not allocated, split the unwritten
575 	extent if blocks has been preallocated already*/
576 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
577 #define EXT4_GET_BLOCKS_CONVERT			0x0010
578 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
579 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
580 	/* Convert extent to initialized after IO complete */
581 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
582 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
583 	/* Eventual metadata allocation (due to growing extent tree)
584 	 * should not fail, so try to use reserved blocks for that.*/
585 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
586 	/* Don't normalize allocation size (used for fallocate) */
587 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
588 	/* Request will not result in inode size update (user for fallocate) */
589 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
590 	/* Convert written extents to unwritten */
591 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
592 	/* Write zeros to newly created written extents */
593 #define EXT4_GET_BLOCKS_ZERO			0x0200
594 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
595 					EXT4_GET_BLOCKS_ZERO)
596 	/* Caller will submit data before dropping transaction handle. This
597 	 * allows jbd2 to avoid submitting data before commit. */
598 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
599 
600 /*
601  * The bit position of these flags must not overlap with any of the
602  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
603  * read_extent_tree_block(), ext4_split_extent_at(),
604  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
605  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
606  * caching the extents when reading from the extent tree while a
607  * truncate or punch hole operation is in progress.
608  */
609 #define EXT4_EX_NOCACHE				0x40000000
610 #define EXT4_EX_FORCE_CACHE			0x20000000
611 
612 /*
613  * Flags used by ext4_free_blocks
614  */
615 #define EXT4_FREE_BLOCKS_METADATA	0x0001
616 #define EXT4_FREE_BLOCKS_FORGET		0x0002
617 #define EXT4_FREE_BLOCKS_VALIDATED	0x0004
618 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE	0x0008
619 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
620 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
621 
622 /*
623  * ioctl commands
624  */
625 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
626 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
627 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
628 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
629 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
630 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
631 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
632 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
633 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
634 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
635 #define EXT4_IOC_MIGRATE		_IO('f', 9)
636  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
637  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
638 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
639 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
640 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
641 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
642 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
643 #define EXT4_IOC_SET_ENCRYPTION_POLICY	FS_IOC_SET_ENCRYPTION_POLICY
644 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	FS_IOC_GET_ENCRYPTION_PWSALT
645 #define EXT4_IOC_GET_ENCRYPTION_POLICY	FS_IOC_GET_ENCRYPTION_POLICY
646 
647 #ifndef FS_IOC_FSGETXATTR
648 /* Until the uapi changes get merged for project quota... */
649 
650 #define FS_IOC_FSGETXATTR		_IOR('X', 31, struct fsxattr)
651 #define FS_IOC_FSSETXATTR		_IOW('X', 32, struct fsxattr)
652 
653 /*
654  * Structure for FS_IOC_FSGETXATTR and FS_IOC_FSSETXATTR.
655  */
656 struct fsxattr {
657 	__u32		fsx_xflags;	/* xflags field value (get/set) */
658 	__u32		fsx_extsize;	/* extsize field value (get/set)*/
659 	__u32		fsx_nextents;	/* nextents field value (get)	*/
660 	__u32		fsx_projid;	/* project identifier (get/set) */
661 	unsigned char	fsx_pad[12];
662 };
663 
664 /*
665  * Flags for the fsx_xflags field
666  */
667 #define FS_XFLAG_REALTIME	0x00000001	/* data in realtime volume */
668 #define FS_XFLAG_PREALLOC	0x00000002	/* preallocated file extents */
669 #define FS_XFLAG_IMMUTABLE	0x00000008	/* file cannot be modified */
670 #define FS_XFLAG_APPEND		0x00000010	/* all writes append */
671 #define FS_XFLAG_SYNC		0x00000020	/* all writes synchronous */
672 #define FS_XFLAG_NOATIME	0x00000040	/* do not update access time */
673 #define FS_XFLAG_NODUMP		0x00000080	/* do not include in backups */
674 #define FS_XFLAG_RTINHERIT	0x00000100	/* create with rt bit set */
675 #define FS_XFLAG_PROJINHERIT	0x00000200	/* create with parents projid */
676 #define FS_XFLAG_NOSYMLINKS	0x00000400	/* disallow symlink creation */
677 #define FS_XFLAG_EXTSIZE	0x00000800	/* extent size allocator hint */
678 #define FS_XFLAG_EXTSZINHERIT	0x00001000	/* inherit inode extent size */
679 #define FS_XFLAG_NODEFRAG	0x00002000  	/* do not defragment */
680 #define FS_XFLAG_FILESTREAM	0x00004000	/* use filestream allocator */
681 #define FS_XFLAG_HASATTR	0x80000000	/* no DIFLAG for this */
682 #endif /* !defined(FS_IOC_FSGETXATTR) */
683 
684 #define EXT4_IOC_FSGETXATTR		FS_IOC_FSGETXATTR
685 #define EXT4_IOC_FSSETXATTR		FS_IOC_FSSETXATTR
686 
687 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
688 
689 /*
690  * Flags for going down operation
691  */
692 #define EXT4_GOING_FLAGS_DEFAULT		0x0	/* going down */
693 #define EXT4_GOING_FLAGS_LOGFLUSH		0x1	/* flush log but not data */
694 #define EXT4_GOING_FLAGS_NOLOGFLUSH		0x2	/* don't flush log nor data */
695 
696 
697 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
698 /*
699  * ioctl commands in 32 bit emulation
700  */
701 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
702 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
703 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
704 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
705 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
706 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
707 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
708 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
709 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
710 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
711 #endif
712 
713 /* Max physical block we can address w/o extents */
714 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
715 
716 /*
717  * Structure of an inode on the disk
718  */
719 struct ext4_inode {
720 	__le16	i_mode;		/* File mode */
721 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
722 	__le32	i_size_lo;	/* Size in bytes */
723 	__le32	i_atime;	/* Access time */
724 	__le32	i_ctime;	/* Inode Change time */
725 	__le32	i_mtime;	/* Modification time */
726 	__le32	i_dtime;	/* Deletion Time */
727 	__le16	i_gid;		/* Low 16 bits of Group Id */
728 	__le16	i_links_count;	/* Links count */
729 	__le32	i_blocks_lo;	/* Blocks count */
730 	__le32	i_flags;	/* File flags */
731 	union {
732 		struct {
733 			__le32  l_i_version;
734 		} linux1;
735 		struct {
736 			__u32  h_i_translator;
737 		} hurd1;
738 		struct {
739 			__u32  m_i_reserved1;
740 		} masix1;
741 	} osd1;				/* OS dependent 1 */
742 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
743 	__le32	i_generation;	/* File version (for NFS) */
744 	__le32	i_file_acl_lo;	/* File ACL */
745 	__le32	i_size_high;
746 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
747 	union {
748 		struct {
749 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
750 			__le16	l_i_file_acl_high;
751 			__le16	l_i_uid_high;	/* these 2 fields */
752 			__le16	l_i_gid_high;	/* were reserved2[0] */
753 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
754 			__le16	l_i_reserved;
755 		} linux2;
756 		struct {
757 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
758 			__u16	h_i_mode_high;
759 			__u16	h_i_uid_high;
760 			__u16	h_i_gid_high;
761 			__u32	h_i_author;
762 		} hurd2;
763 		struct {
764 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
765 			__le16	m_i_file_acl_high;
766 			__u32	m_i_reserved2[2];
767 		} masix2;
768 	} osd2;				/* OS dependent 2 */
769 	__le16	i_extra_isize;
770 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
771 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
772 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
773 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
774 	__le32  i_crtime;       /* File Creation time */
775 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
776 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
777 	__le32	i_projid;	/* Project ID */
778 };
779 
780 struct move_extent {
781 	__u32 reserved;		/* should be zero */
782 	__u32 donor_fd;		/* donor file descriptor */
783 	__u64 orig_start;	/* logical start offset in block for orig */
784 	__u64 donor_start;	/* logical start offset in block for donor */
785 	__u64 len;		/* block length to be moved */
786 	__u64 moved_len;	/* moved block length */
787 };
788 
789 #define EXT4_EPOCH_BITS 2
790 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
791 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
792 
793 /*
794  * Extended fields will fit into an inode if the filesystem was formatted
795  * with large inodes (-I 256 or larger) and there are not currently any EAs
796  * consuming all of the available space. For new inodes we always reserve
797  * enough space for the kernel's known extended fields, but for inodes
798  * created with an old kernel this might not have been the case. None of
799  * the extended inode fields is critical for correct filesystem operation.
800  * This macro checks if a certain field fits in the inode. Note that
801  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
802  */
803 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
804 	((offsetof(typeof(*ext4_inode), field) +	\
805 	  sizeof((ext4_inode)->field))			\
806 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
807 	    (einode)->i_extra_isize))			\
808 
809 /*
810  * We use an encoding that preserves the times for extra epoch "00":
811  *
812  * extra  msb of                         adjust for signed
813  * epoch  32-bit                         32-bit tv_sec to
814  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
815  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
816  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
817  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
818  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
819  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
820  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
821  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
822  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
823  *
824  * Note that previous versions of the kernel on 64-bit systems would
825  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
826  * 1970.  e2fsck will correct this, assuming that it is run on the
827  * affected filesystem before 2242.
828  */
829 
830 static inline __le32 ext4_encode_extra_time(struct timespec *time)
831 {
832 	u32 extra = sizeof(time->tv_sec) > 4 ?
833 		((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK : 0;
834 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
835 }
836 
837 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
838 {
839 	if (unlikely(sizeof(time->tv_sec) > 4 &&
840 			(extra & cpu_to_le32(EXT4_EPOCH_MASK)))) {
841 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,20,0)
842 		/* Handle legacy encoding of pre-1970 dates with epoch
843 		 * bits 1,1.  We assume that by kernel version 4.20,
844 		 * everyone will have run fsck over the affected
845 		 * filesystems to correct the problem.  (This
846 		 * backwards compatibility may be removed before this
847 		 * time, at the discretion of the ext4 developers.)
848 		 */
849 		u64 extra_bits = le32_to_cpu(extra) & EXT4_EPOCH_MASK;
850 		if (extra_bits == 3 && ((time->tv_sec) & 0x80000000) != 0)
851 			extra_bits = 0;
852 		time->tv_sec += extra_bits << 32;
853 #else
854 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
855 #endif
856 	}
857 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
858 }
859 
860 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)			       \
861 do {									       \
862 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	       \
863 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
864 		(raw_inode)->xtime ## _extra =				       \
865 				ext4_encode_extra_time(&(inode)->xtime);       \
866 } while (0)
867 
868 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
869 do {									       \
870 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
871 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
872 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
873 		(raw_inode)->xtime ## _extra =				       \
874 				ext4_encode_extra_time(&(einode)->xtime);      \
875 } while (0)
876 
877 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)			       \
878 do {									       \
879 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
880 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
881 		ext4_decode_extra_time(&(inode)->xtime,			       \
882 				       raw_inode->xtime ## _extra);	       \
883 	else								       \
884 		(inode)->xtime.tv_nsec = 0;				       \
885 } while (0)
886 
887 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
888 do {									       \
889 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
890 		(einode)->xtime.tv_sec = 				       \
891 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
892 	else								       \
893 		(einode)->xtime.tv_sec = 0;				       \
894 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
895 		ext4_decode_extra_time(&(einode)->xtime,		       \
896 				       raw_inode->xtime ## _extra);	       \
897 	else								       \
898 		(einode)->xtime.tv_nsec = 0;				       \
899 } while (0)
900 
901 #define i_disk_version osd1.linux1.l_i_version
902 
903 #if defined(__KERNEL__) || defined(__linux__)
904 #define i_reserved1	osd1.linux1.l_i_reserved1
905 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
906 #define i_blocks_high	osd2.linux2.l_i_blocks_high
907 #define i_uid_low	i_uid
908 #define i_gid_low	i_gid
909 #define i_uid_high	osd2.linux2.l_i_uid_high
910 #define i_gid_high	osd2.linux2.l_i_gid_high
911 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
912 
913 #elif defined(__GNU__)
914 
915 #define i_translator	osd1.hurd1.h_i_translator
916 #define i_uid_high	osd2.hurd2.h_i_uid_high
917 #define i_gid_high	osd2.hurd2.h_i_gid_high
918 #define i_author	osd2.hurd2.h_i_author
919 
920 #elif defined(__masix__)
921 
922 #define i_reserved1	osd1.masix1.m_i_reserved1
923 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
924 #define i_reserved2	osd2.masix2.m_i_reserved2
925 
926 #endif /* defined(__KERNEL__) || defined(__linux__) */
927 
928 #include "extents_status.h"
929 
930 /*
931  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
932  *
933  * These are needed to avoid lockdep false positives when we need to
934  * allocate blocks to the quota inode during ext4_map_blocks(), while
935  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
936  * do quota tracking for the quota inode, this avoids deadlock (as
937  * well as infinite recursion, since it isn't turtles all the way
938  * down...)
939  *
940  *  I_DATA_SEM_NORMAL - Used for most inodes
941  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
942  *			  where the second inode has larger inode number
943  *			  than the first
944  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
945  */
946 enum {
947 	I_DATA_SEM_NORMAL = 0,
948 	I_DATA_SEM_OTHER,
949 	I_DATA_SEM_QUOTA,
950 };
951 
952 
953 /*
954  * fourth extended file system inode data in memory
955  */
956 struct ext4_inode_info {
957 	__le32	i_data[15];	/* unconverted */
958 	__u32	i_dtime;
959 	ext4_fsblk_t	i_file_acl;
960 
961 	/*
962 	 * i_block_group is the number of the block group which contains
963 	 * this file's inode.  Constant across the lifetime of the inode,
964 	 * it is ued for making block allocation decisions - we try to
965 	 * place a file's data blocks near its inode block, and new inodes
966 	 * near to their parent directory's inode.
967 	 */
968 	ext4_group_t	i_block_group;
969 	ext4_lblk_t	i_dir_start_lookup;
970 #if (BITS_PER_LONG < 64)
971 	unsigned long	i_state_flags;		/* Dynamic state flags */
972 #endif
973 	unsigned long	i_flags;
974 
975 	/*
976 	 * Extended attributes can be read independently of the main file
977 	 * data. Taking i_mutex even when reading would cause contention
978 	 * between readers of EAs and writers of regular file data, so
979 	 * instead we synchronize on xattr_sem when reading or changing
980 	 * EAs.
981 	 */
982 	struct rw_semaphore xattr_sem;
983 
984 	struct list_head i_orphan;	/* unlinked but open inodes */
985 
986 	/*
987 	 * i_disksize keeps track of what the inode size is ON DISK, not
988 	 * in memory.  During truncate, i_size is set to the new size by
989 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
990 	 * set i_disksize to 0 until the truncate is actually under way.
991 	 *
992 	 * The intent is that i_disksize always represents the blocks which
993 	 * are used by this file.  This allows recovery to restart truncate
994 	 * on orphans if we crash during truncate.  We actually write i_disksize
995 	 * into the on-disk inode when writing inodes out, instead of i_size.
996 	 *
997 	 * The only time when i_disksize and i_size may be different is when
998 	 * a truncate is in progress.  The only things which change i_disksize
999 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
1000 	 */
1001 	loff_t	i_disksize;
1002 
1003 	/*
1004 	 * i_data_sem is for serialising ext4_truncate() against
1005 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
1006 	 * data tree are chopped off during truncate. We can't do that in
1007 	 * ext4 because whenever we perform intermediate commits during
1008 	 * truncate, the inode and all the metadata blocks *must* be in a
1009 	 * consistent state which allows truncation of the orphans to restart
1010 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
1011 	 * by other means, so we have i_data_sem.
1012 	 */
1013 	struct rw_semaphore i_data_sem;
1014 	/*
1015 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
1016 	 * operations. We have to make sure that new page cannot be faulted in
1017 	 * a section of the inode that is being punched. We cannot easily use
1018 	 * i_data_sem for this since we need protection for the whole punch
1019 	 * operation and i_data_sem ranks below transaction start so we have
1020 	 * to occasionally drop it.
1021 	 */
1022 	struct rw_semaphore i_mmap_sem;
1023 	struct inode vfs_inode;
1024 	struct jbd2_inode *jinode;
1025 
1026 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
1027 
1028 	/*
1029 	 * File creation time. Its function is same as that of
1030 	 * struct timespec i_{a,c,m}time in the generic inode.
1031 	 */
1032 	struct timespec i_crtime;
1033 
1034 	/* mballoc */
1035 	struct list_head i_prealloc_list;
1036 	spinlock_t i_prealloc_lock;
1037 
1038 	/* extents status tree */
1039 	struct ext4_es_tree i_es_tree;
1040 	rwlock_t i_es_lock;
1041 	struct list_head i_es_list;
1042 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1043 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1044 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1045 					   extents to shrink. Protected by
1046 					   i_es_lock  */
1047 
1048 	/* ialloc */
1049 	ext4_group_t	i_last_alloc_group;
1050 
1051 	/* allocation reservation info for delalloc */
1052 	/* In case of bigalloc, these refer to clusters rather than blocks */
1053 	unsigned int i_reserved_data_blocks;
1054 	unsigned int i_reserved_meta_blocks;
1055 	unsigned int i_allocated_meta_blocks;
1056 	ext4_lblk_t i_da_metadata_calc_last_lblock;
1057 	int i_da_metadata_calc_len;
1058 
1059 	/* on-disk additional length */
1060 	__u16 i_extra_isize;
1061 
1062 	/* Indicate the inline data space. */
1063 	u16 i_inline_off;
1064 	u16 i_inline_size;
1065 
1066 #ifdef CONFIG_QUOTA
1067 	/* quota space reservation, managed internally by quota code */
1068 	qsize_t i_reserved_quota;
1069 #endif
1070 
1071 	/* Lock protecting lists below */
1072 	spinlock_t i_completed_io_lock;
1073 	/*
1074 	 * Completed IOs that need unwritten extents handling and have
1075 	 * transaction reserved
1076 	 */
1077 	struct list_head i_rsv_conversion_list;
1078 	struct work_struct i_rsv_conversion_work;
1079 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1080 
1081 	spinlock_t i_block_reservation_lock;
1082 
1083 	/*
1084 	 * Transactions that contain inode's metadata needed to complete
1085 	 * fsync and fdatasync, respectively.
1086 	 */
1087 	tid_t i_sync_tid;
1088 	tid_t i_datasync_tid;
1089 
1090 #ifdef CONFIG_QUOTA
1091 	struct dquot *i_dquot[MAXQUOTAS];
1092 #endif
1093 
1094 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1095 	__u32 i_csum_seed;
1096 
1097 	kprojid_t i_projid;
1098 };
1099 
1100 /*
1101  * File system states
1102  */
1103 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1104 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1105 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1106 
1107 /*
1108  * Misc. filesystem flags
1109  */
1110 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1111 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1112 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1113 
1114 /*
1115  * Mount flags set via mount options or defaults
1116  */
1117 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1118 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1119 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1120 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1121 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1122 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1123 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1124 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1125 #ifdef CONFIG_FS_DAX
1126 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
1127 #else
1128 #define EXT4_MOUNT_DAX			0
1129 #endif
1130 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1131 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1132 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1133 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1134 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1135 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1136 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1137 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1138 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1139 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1140 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1141 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1142 						 * enable enforcement for hidden
1143 						 * quota files */
1144 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1145 						  * enforcement for hidden quota
1146 						  * files */
1147 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1148 						  * enforcement */
1149 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1150 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1151 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1152 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1153 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1154 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1155 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1156 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1157 
1158 /*
1159  * Mount flags set either automatically (could not be set by mount option)
1160  * based on per file system feature or property or in special cases such as
1161  * distinguishing between explicit mount option definition and default.
1162  */
1163 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1164 						      specified delalloc */
1165 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1166 						      size of blocksize * 8
1167 						      blocks */
1168 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1169 						      file systems */
1170 
1171 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1172 						specified journal checksum */
1173 
1174 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1175 						~EXT4_MOUNT_##opt
1176 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1177 						EXT4_MOUNT_##opt
1178 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1179 					 EXT4_MOUNT_##opt)
1180 
1181 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1182 						~EXT4_MOUNT2_##opt
1183 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1184 						EXT4_MOUNT2_##opt
1185 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1186 					 EXT4_MOUNT2_##opt)
1187 
1188 #define ext4_test_and_set_bit		__test_and_set_bit_le
1189 #define ext4_set_bit			__set_bit_le
1190 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1191 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1192 #define ext4_clear_bit			__clear_bit_le
1193 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1194 #define ext4_test_bit			test_bit_le
1195 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1196 #define ext4_find_next_bit		find_next_bit_le
1197 
1198 extern void ext4_set_bits(void *bm, int cur, int len);
1199 
1200 /*
1201  * Maximal mount counts between two filesystem checks
1202  */
1203 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1204 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1205 
1206 /*
1207  * Behaviour when detecting errors
1208  */
1209 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1210 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1211 #define EXT4_ERRORS_PANIC		3	/* Panic */
1212 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1213 
1214 /* Metadata checksum algorithm codes */
1215 #define EXT4_CRC32C_CHKSUM		1
1216 
1217 /*
1218  * Structure of the super block
1219  */
1220 struct ext4_super_block {
1221 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1222 	__le32	s_blocks_count_lo;	/* Blocks count */
1223 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1224 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1225 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1226 	__le32	s_first_data_block;	/* First Data Block */
1227 	__le32	s_log_block_size;	/* Block size */
1228 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1229 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1230 	__le32	s_clusters_per_group;	/* # Clusters per group */
1231 	__le32	s_inodes_per_group;	/* # Inodes per group */
1232 	__le32	s_mtime;		/* Mount time */
1233 /*30*/	__le32	s_wtime;		/* Write time */
1234 	__le16	s_mnt_count;		/* Mount count */
1235 	__le16	s_max_mnt_count;	/* Maximal mount count */
1236 	__le16	s_magic;		/* Magic signature */
1237 	__le16	s_state;		/* File system state */
1238 	__le16	s_errors;		/* Behaviour when detecting errors */
1239 	__le16	s_minor_rev_level;	/* minor revision level */
1240 /*40*/	__le32	s_lastcheck;		/* time of last check */
1241 	__le32	s_checkinterval;	/* max. time between checks */
1242 	__le32	s_creator_os;		/* OS */
1243 	__le32	s_rev_level;		/* Revision level */
1244 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1245 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1246 	/*
1247 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1248 	 *
1249 	 * Note: the difference between the compatible feature set and
1250 	 * the incompatible feature set is that if there is a bit set
1251 	 * in the incompatible feature set that the kernel doesn't
1252 	 * know about, it should refuse to mount the filesystem.
1253 	 *
1254 	 * e2fsck's requirements are more strict; if it doesn't know
1255 	 * about a feature in either the compatible or incompatible
1256 	 * feature set, it must abort and not try to meddle with
1257 	 * things it doesn't understand...
1258 	 */
1259 	__le32	s_first_ino;		/* First non-reserved inode */
1260 	__le16  s_inode_size;		/* size of inode structure */
1261 	__le16	s_block_group_nr;	/* block group # of this superblock */
1262 	__le32	s_feature_compat;	/* compatible feature set */
1263 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1264 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1265 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1266 /*78*/	char	s_volume_name[16];	/* volume name */
1267 /*88*/	char	s_last_mounted[64];	/* directory where last mounted */
1268 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1269 	/*
1270 	 * Performance hints.  Directory preallocation should only
1271 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1272 	 */
1273 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1274 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1275 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1276 	/*
1277 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1278 	 */
1279 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1280 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1281 	__le32	s_journal_dev;		/* device number of journal file */
1282 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1283 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1284 	__u8	s_def_hash_version;	/* Default hash version to use */
1285 	__u8	s_jnl_backup_type;
1286 	__le16  s_desc_size;		/* size of group descriptor */
1287 /*100*/	__le32	s_default_mount_opts;
1288 	__le32	s_first_meta_bg;	/* First metablock block group */
1289 	__le32	s_mkfs_time;		/* When the filesystem was created */
1290 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1291 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1292 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1293 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1294 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1295 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1296 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1297 	__le32	s_flags;		/* Miscellaneous flags */
1298 	__le16  s_raid_stride;		/* RAID stride */
1299 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1300 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1301 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1302 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1303 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1304 	__u8	s_encryption_level;	/* versioning level for encryption */
1305 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1306 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1307 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1308 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1309 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1310 					      snapshot's future use */
1311 	__le32	s_snapshot_list;	/* inode number of the head of the
1312 					   on-disk snapshot list */
1313 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1314 	__le32	s_error_count;		/* number of fs errors */
1315 	__le32	s_first_error_time;	/* first time an error happened */
1316 	__le32	s_first_error_ino;	/* inode involved in first error */
1317 	__le64	s_first_error_block;	/* block involved of first error */
1318 	__u8	s_first_error_func[32];	/* function where the error happened */
1319 	__le32	s_first_error_line;	/* line number where error happened */
1320 	__le32	s_last_error_time;	/* most recent time of an error */
1321 	__le32	s_last_error_ino;	/* inode involved in last error */
1322 	__le32	s_last_error_line;	/* line number where error happened */
1323 	__le64	s_last_error_block;	/* block involved of last error */
1324 	__u8	s_last_error_func[32];	/* function where the error happened */
1325 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1326 	__u8	s_mount_opts[64];
1327 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1328 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1329 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1330 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1331 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1332 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1333 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1334 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1335 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1336 	__le32	s_reserved[98];		/* Padding to the end of the block */
1337 	__le32	s_checksum;		/* crc32c(superblock) */
1338 };
1339 
1340 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1341 
1342 #ifdef __KERNEL__
1343 
1344 /*
1345  * run-time mount flags
1346  */
1347 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1348 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1349 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1350 
1351 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1352 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1353 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1354 #else
1355 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1356 #endif
1357 
1358 /* Number of quota types we support */
1359 #define EXT4_MAXQUOTAS 3
1360 
1361 /*
1362  * fourth extended-fs super-block data in memory
1363  */
1364 struct ext4_sb_info {
1365 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1366 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1367 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1368 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1369 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1370 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1371 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1372 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1373 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1374 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1375 	unsigned long s_overhead;  /* # of fs overhead clusters */
1376 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1377 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1378 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1379 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1380 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1381 	struct buffer_head **s_group_desc;
1382 	unsigned int s_mount_opt;
1383 	unsigned int s_mount_opt2;
1384 	unsigned int s_mount_flags;
1385 	unsigned int s_def_mount_opt;
1386 	ext4_fsblk_t s_sb_block;
1387 	atomic64_t s_resv_clusters;
1388 	kuid_t s_resuid;
1389 	kgid_t s_resgid;
1390 	unsigned short s_mount_state;
1391 	unsigned short s_pad;
1392 	int s_addr_per_block_bits;
1393 	int s_desc_per_block_bits;
1394 	int s_inode_size;
1395 	int s_first_ino;
1396 	unsigned int s_inode_readahead_blks;
1397 	unsigned int s_inode_goal;
1398 	spinlock_t s_next_gen_lock;
1399 	u32 s_next_generation;
1400 	u32 s_hash_seed[4];
1401 	int s_def_hash_version;
1402 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1403 	struct percpu_counter s_freeclusters_counter;
1404 	struct percpu_counter s_freeinodes_counter;
1405 	struct percpu_counter s_dirs_counter;
1406 	struct percpu_counter s_dirtyclusters_counter;
1407 	struct blockgroup_lock *s_blockgroup_lock;
1408 	struct proc_dir_entry *s_proc;
1409 	struct kobject s_kobj;
1410 	struct completion s_kobj_unregister;
1411 	struct super_block *s_sb;
1412 
1413 	/* Journaling */
1414 	struct journal_s *s_journal;
1415 	struct list_head s_orphan;
1416 	struct mutex s_orphan_lock;
1417 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1418 	unsigned long s_commit_interval;
1419 	u32 s_max_batch_time;
1420 	u32 s_min_batch_time;
1421 	struct block_device *journal_bdev;
1422 #ifdef CONFIG_QUOTA
1423 	char *s_qf_names[EXT4_MAXQUOTAS];	/* Names of quota files with journalled quota */
1424 	int s_jquota_fmt;			/* Format of quota to use */
1425 #endif
1426 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1427 	struct rb_root system_blks;
1428 
1429 #ifdef EXTENTS_STATS
1430 	/* ext4 extents stats */
1431 	unsigned long s_ext_min;
1432 	unsigned long s_ext_max;
1433 	unsigned long s_depth_max;
1434 	spinlock_t s_ext_stats_lock;
1435 	unsigned long s_ext_blocks;
1436 	unsigned long s_ext_extents;
1437 #endif
1438 
1439 	/* for buddy allocator */
1440 	struct ext4_group_info ***s_group_info;
1441 	struct inode *s_buddy_cache;
1442 	spinlock_t s_md_lock;
1443 	unsigned short *s_mb_offsets;
1444 	unsigned int *s_mb_maxs;
1445 	unsigned int s_group_info_size;
1446 	unsigned int s_mb_free_pending;
1447 
1448 	/* tunables */
1449 	unsigned long s_stripe;
1450 	unsigned int s_mb_stream_request;
1451 	unsigned int s_mb_max_to_scan;
1452 	unsigned int s_mb_min_to_scan;
1453 	unsigned int s_mb_stats;
1454 	unsigned int s_mb_order2_reqs;
1455 	unsigned int s_mb_group_prealloc;
1456 	unsigned int s_max_dir_size_kb;
1457 	/* where last allocation was done - for stream allocation */
1458 	unsigned long s_mb_last_group;
1459 	unsigned long s_mb_last_start;
1460 
1461 	/* stats for buddy allocator */
1462 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1463 	atomic_t s_bal_success;	/* we found long enough chunks */
1464 	atomic_t s_bal_allocated;	/* in blocks */
1465 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1466 	atomic_t s_bal_goals;	/* goal hits */
1467 	atomic_t s_bal_breaks;	/* too long searches */
1468 	atomic_t s_bal_2orders;	/* 2^order hits */
1469 	spinlock_t s_bal_lock;
1470 	unsigned long s_mb_buddies_generated;
1471 	unsigned long long s_mb_generation_time;
1472 	atomic_t s_mb_lost_chunks;
1473 	atomic_t s_mb_preallocated;
1474 	atomic_t s_mb_discarded;
1475 	atomic_t s_lock_busy;
1476 
1477 	/* locality groups */
1478 	struct ext4_locality_group __percpu *s_locality_groups;
1479 
1480 	/* for write statistics */
1481 	unsigned long s_sectors_written_start;
1482 	u64 s_kbytes_written;
1483 
1484 	/* the size of zero-out chunk */
1485 	unsigned int s_extent_max_zeroout_kb;
1486 
1487 	unsigned int s_log_groups_per_flex;
1488 	struct flex_groups *s_flex_groups;
1489 	ext4_group_t s_flex_groups_allocated;
1490 
1491 	/* workqueue for reserved extent conversions (buffered io) */
1492 	struct workqueue_struct *rsv_conversion_wq;
1493 
1494 	/* timer for periodic error stats printing */
1495 	struct timer_list s_err_report;
1496 
1497 	/* Lazy inode table initialization info */
1498 	struct ext4_li_request *s_li_request;
1499 	/* Wait multiplier for lazy initialization thread */
1500 	unsigned int s_li_wait_mult;
1501 
1502 	/* Kernel thread for multiple mount protection */
1503 	struct task_struct *s_mmp_tsk;
1504 
1505 	/* record the last minlen when FITRIM is called. */
1506 	atomic_t s_last_trim_minblks;
1507 
1508 	/* Reference to checksum algorithm driver via cryptoapi */
1509 	struct crypto_shash *s_chksum_driver;
1510 
1511 	/* Precomputed FS UUID checksum for seeding other checksums */
1512 	__u32 s_csum_seed;
1513 
1514 	/* Reclaim extents from extent status tree */
1515 	struct shrinker s_es_shrinker;
1516 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1517 	long s_es_nr_inode;
1518 	struct ext4_es_stats s_es_stats;
1519 	struct mb_cache *s_mb_cache;
1520 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1521 
1522 	/* Ratelimit ext4 messages. */
1523 	struct ratelimit_state s_err_ratelimit_state;
1524 	struct ratelimit_state s_warning_ratelimit_state;
1525 	struct ratelimit_state s_msg_ratelimit_state;
1526 
1527 	/* Barrier between changing inodes' journal flags and writepages ops. */
1528 	struct percpu_rw_semaphore s_journal_flag_rwsem;
1529 };
1530 
1531 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1532 {
1533 	return sb->s_fs_info;
1534 }
1535 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1536 {
1537 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1538 }
1539 
1540 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1541 {
1542 	return ino == EXT4_ROOT_INO ||
1543 		ino == EXT4_USR_QUOTA_INO ||
1544 		ino == EXT4_GRP_QUOTA_INO ||
1545 		ino == EXT4_BOOT_LOADER_INO ||
1546 		ino == EXT4_JOURNAL_INO ||
1547 		ino == EXT4_RESIZE_INO ||
1548 		(ino >= EXT4_FIRST_INO(sb) &&
1549 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1550 }
1551 
1552 /*
1553  * Inode dynamic state flags
1554  */
1555 enum {
1556 	EXT4_STATE_JDATA,		/* journaled data exists */
1557 	EXT4_STATE_NEW,			/* inode is newly created */
1558 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1559 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1560 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1561 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1562 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1563 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1564 	EXT4_STATE_DIOREAD_LOCK,	/* Disable support for dio read
1565 					   nolocking */
1566 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1567 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1568 };
1569 
1570 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1571 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1572 {									\
1573 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1574 }									\
1575 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1576 {									\
1577 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1578 }									\
1579 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1580 {									\
1581 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1582 }
1583 
1584 /* Add these declarations here only so that these functions can be
1585  * found by name.  Otherwise, they are very hard to locate. */
1586 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1587 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1588 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1589 EXT4_INODE_BIT_FNS(flag, flags, 0)
1590 
1591 /* Add these declarations here only so that these functions can be
1592  * found by name.  Otherwise, they are very hard to locate. */
1593 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1594 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1595 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1596 #if (BITS_PER_LONG < 64)
1597 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1598 
1599 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1600 {
1601 	(ei)->i_state_flags = 0;
1602 }
1603 #else
1604 EXT4_INODE_BIT_FNS(state, flags, 32)
1605 
1606 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1607 {
1608 	/* We depend on the fact that callers will set i_flags */
1609 }
1610 #endif
1611 #else
1612 /* Assume that user mode programs are passing in an ext4fs superblock, not
1613  * a kernel struct super_block.  This will allow us to call the feature-test
1614  * macros from user land. */
1615 #define EXT4_SB(sb)	(sb)
1616 #endif
1617 
1618 /*
1619  * Returns true if the inode is inode is encrypted
1620  */
1621 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1622 
1623 /*
1624  * Codes for operating systems
1625  */
1626 #define EXT4_OS_LINUX		0
1627 #define EXT4_OS_HURD		1
1628 #define EXT4_OS_MASIX		2
1629 #define EXT4_OS_FREEBSD		3
1630 #define EXT4_OS_LITES		4
1631 
1632 /*
1633  * Revision levels
1634  */
1635 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1636 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1637 
1638 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1639 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1640 
1641 #define EXT4_GOOD_OLD_INODE_SIZE 128
1642 
1643 /*
1644  * Feature set definitions
1645  */
1646 
1647 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1648 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1649 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1650 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1651 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1652 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1653 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1654 
1655 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1656 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1657 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1658 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1659 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1660 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1661 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1662 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1663 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1664 /*
1665  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1666  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1667  * all other data structures' checksums.  However, the METADATA_CSUM and
1668  * GDT_CSUM bits are mutually exclusive.
1669  */
1670 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1671 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1672 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1673 
1674 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1675 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1676 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1677 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1678 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1679 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1680 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1681 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1682 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1683 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1684 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1685 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1686 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1687 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1688 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1689 
1690 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1691 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1692 { \
1693 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1694 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1695 } \
1696 static inline void ext4_set_feature_##name(struct super_block *sb) \
1697 { \
1698 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1699 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1700 } \
1701 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1702 { \
1703 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1704 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1705 }
1706 
1707 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1708 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1709 { \
1710 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1711 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1712 } \
1713 static inline void ext4_set_feature_##name(struct super_block *sb) \
1714 { \
1715 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1716 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1717 } \
1718 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1719 { \
1720 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1721 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1722 }
1723 
1724 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1725 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1726 { \
1727 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1728 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1729 } \
1730 static inline void ext4_set_feature_##name(struct super_block *sb) \
1731 { \
1732 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
1733 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1734 } \
1735 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1736 { \
1737 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1738 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1739 }
1740 
1741 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1742 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1743 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1744 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1745 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1746 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1747 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1748 
1749 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1750 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1751 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1752 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1753 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1754 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1755 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1756 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1757 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1758 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1759 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1760 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1761 
1762 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1763 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
1764 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
1765 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
1766 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
1767 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
1768 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
1769 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
1770 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
1771 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
1772 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
1773 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
1774 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
1775 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
1776 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
1777 
1778 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1779 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1780 					 EXT4_FEATURE_INCOMPAT_META_BG)
1781 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1782 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1783 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1784 
1785 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1786 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1787 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1788 					 EXT4_FEATURE_INCOMPAT_META_BG)
1789 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1790 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1791 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1792 
1793 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1794 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1795 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1796 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1797 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1798 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1799 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1800 					 EXT4_FEATURE_INCOMPAT_MMP | \
1801 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1802 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1803 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED)
1804 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1805 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1806 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1807 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1808 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1809 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1810 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1811 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1812 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1813 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
1814 					 EXT4_FEATURE_RO_COMPAT_PROJECT)
1815 
1816 #define EXTN_FEATURE_FUNCS(ver) \
1817 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1818 { \
1819 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1820 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1821 } \
1822 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1823 { \
1824 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1825 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1826 } \
1827 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1828 { \
1829 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1830 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1831 }
1832 
1833 EXTN_FEATURE_FUNCS(2)
1834 EXTN_FEATURE_FUNCS(3)
1835 EXTN_FEATURE_FUNCS(4)
1836 
1837 static inline bool ext4_has_compat_features(struct super_block *sb)
1838 {
1839 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1840 }
1841 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1842 {
1843 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1844 }
1845 static inline bool ext4_has_incompat_features(struct super_block *sb)
1846 {
1847 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
1848 }
1849 
1850 /*
1851  * Superblock flags
1852  */
1853 #define EXT4_FLAGS_RESIZING	0
1854 #define EXT4_FLAGS_SHUTDOWN	1
1855 
1856 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
1857 {
1858 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
1859 }
1860 
1861 
1862 /*
1863  * Default values for user and/or group using reserved blocks
1864  */
1865 #define	EXT4_DEF_RESUID		0
1866 #define	EXT4_DEF_RESGID		0
1867 
1868 /*
1869  * Default project ID
1870  */
1871 #define	EXT4_DEF_PROJID		0
1872 
1873 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1874 
1875 /*
1876  * Default mount options
1877  */
1878 #define EXT4_DEFM_DEBUG		0x0001
1879 #define EXT4_DEFM_BSDGROUPS	0x0002
1880 #define EXT4_DEFM_XATTR_USER	0x0004
1881 #define EXT4_DEFM_ACL		0x0008
1882 #define EXT4_DEFM_UID16		0x0010
1883 #define EXT4_DEFM_JMODE		0x0060
1884 #define EXT4_DEFM_JMODE_DATA	0x0020
1885 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1886 #define EXT4_DEFM_JMODE_WBACK	0x0060
1887 #define EXT4_DEFM_NOBARRIER	0x0100
1888 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1889 #define EXT4_DEFM_DISCARD	0x0400
1890 #define EXT4_DEFM_NODELALLOC	0x0800
1891 
1892 /*
1893  * Default journal batch times
1894  */
1895 #define EXT4_DEF_MIN_BATCH_TIME	0
1896 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1897 
1898 /*
1899  * Minimum number of groups in a flexgroup before we separate out
1900  * directories into the first block group of a flexgroup
1901  */
1902 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1903 
1904 /*
1905  * Structure of a directory entry
1906  */
1907 #define EXT4_NAME_LEN 255
1908 
1909 struct ext4_dir_entry {
1910 	__le32	inode;			/* Inode number */
1911 	__le16	rec_len;		/* Directory entry length */
1912 	__le16	name_len;		/* Name length */
1913 	char	name[EXT4_NAME_LEN];	/* File name */
1914 };
1915 
1916 /*
1917  * The new version of the directory entry.  Since EXT4 structures are
1918  * stored in intel byte order, and the name_len field could never be
1919  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1920  * file_type field.
1921  */
1922 struct ext4_dir_entry_2 {
1923 	__le32	inode;			/* Inode number */
1924 	__le16	rec_len;		/* Directory entry length */
1925 	__u8	name_len;		/* Name length */
1926 	__u8	file_type;
1927 	char	name[EXT4_NAME_LEN];	/* File name */
1928 };
1929 
1930 /*
1931  * This is a bogus directory entry at the end of each leaf block that
1932  * records checksums.
1933  */
1934 struct ext4_dir_entry_tail {
1935 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1936 	__le16	det_rec_len;		/* 12 */
1937 	__u8	det_reserved_zero2;	/* Zero name length */
1938 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1939 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1940 };
1941 
1942 #define EXT4_DIRENT_TAIL(block, blocksize) \
1943 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1944 					((blocksize) - \
1945 					 sizeof(struct ext4_dir_entry_tail))))
1946 
1947 /*
1948  * Ext4 directory file types.  Only the low 3 bits are used.  The
1949  * other bits are reserved for now.
1950  */
1951 #define EXT4_FT_UNKNOWN		0
1952 #define EXT4_FT_REG_FILE	1
1953 #define EXT4_FT_DIR		2
1954 #define EXT4_FT_CHRDEV		3
1955 #define EXT4_FT_BLKDEV		4
1956 #define EXT4_FT_FIFO		5
1957 #define EXT4_FT_SOCK		6
1958 #define EXT4_FT_SYMLINK		7
1959 
1960 #define EXT4_FT_MAX		8
1961 
1962 #define EXT4_FT_DIR_CSUM	0xDE
1963 
1964 /*
1965  * EXT4_DIR_PAD defines the directory entries boundaries
1966  *
1967  * NOTE: It must be a multiple of 4
1968  */
1969 #define EXT4_DIR_PAD			4
1970 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1971 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1972 					 ~EXT4_DIR_ROUND)
1973 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1974 
1975 /*
1976  * If we ever get support for fs block sizes > page_size, we'll need
1977  * to remove the #if statements in the next two functions...
1978  */
1979 static inline unsigned int
1980 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1981 {
1982 	unsigned len = le16_to_cpu(dlen);
1983 
1984 #if (PAGE_SIZE >= 65536)
1985 	if (len == EXT4_MAX_REC_LEN || len == 0)
1986 		return blocksize;
1987 	return (len & 65532) | ((len & 3) << 16);
1988 #else
1989 	return len;
1990 #endif
1991 }
1992 
1993 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1994 {
1995 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1996 		BUG();
1997 #if (PAGE_SIZE >= 65536)
1998 	if (len < 65536)
1999 		return cpu_to_le16(len);
2000 	if (len == blocksize) {
2001 		if (blocksize == 65536)
2002 			return cpu_to_le16(EXT4_MAX_REC_LEN);
2003 		else
2004 			return cpu_to_le16(0);
2005 	}
2006 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2007 #else
2008 	return cpu_to_le16(len);
2009 #endif
2010 }
2011 
2012 /*
2013  * Hash Tree Directory indexing
2014  * (c) Daniel Phillips, 2001
2015  */
2016 
2017 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2018 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2019 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
2020 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2021 
2022 /* Legal values for the dx_root hash_version field: */
2023 
2024 #define DX_HASH_LEGACY		0
2025 #define DX_HASH_HALF_MD4	1
2026 #define DX_HASH_TEA		2
2027 #define DX_HASH_LEGACY_UNSIGNED	3
2028 #define DX_HASH_HALF_MD4_UNSIGNED	4
2029 #define DX_HASH_TEA_UNSIGNED		5
2030 
2031 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2032 			      const void *address, unsigned int length)
2033 {
2034 	struct {
2035 		struct shash_desc shash;
2036 		char ctx[4];
2037 	} desc;
2038 	int err;
2039 
2040 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2041 
2042 	desc.shash.tfm = sbi->s_chksum_driver;
2043 	desc.shash.flags = 0;
2044 	*(u32 *)desc.ctx = crc;
2045 
2046 	err = crypto_shash_update(&desc.shash, address, length);
2047 	BUG_ON(err);
2048 
2049 	return *(u32 *)desc.ctx;
2050 }
2051 
2052 #ifdef __KERNEL__
2053 
2054 /* hash info structure used by the directory hash */
2055 struct dx_hash_info
2056 {
2057 	u32		hash;
2058 	u32		minor_hash;
2059 	int		hash_version;
2060 	u32		*seed;
2061 };
2062 
2063 
2064 /* 32 and 64 bit signed EOF for dx directories */
2065 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2066 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2067 
2068 
2069 /*
2070  * Control parameters used by ext4_htree_next_block
2071  */
2072 #define HASH_NB_ALWAYS		1
2073 
2074 struct ext4_filename {
2075 	const struct qstr *usr_fname;
2076 	struct fscrypt_str disk_name;
2077 	struct dx_hash_info hinfo;
2078 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2079 	struct fscrypt_str crypto_buf;
2080 #endif
2081 };
2082 
2083 #define fname_name(p) ((p)->disk_name.name)
2084 #define fname_len(p)  ((p)->disk_name.len)
2085 
2086 /*
2087  * Describe an inode's exact location on disk and in memory
2088  */
2089 struct ext4_iloc
2090 {
2091 	struct buffer_head *bh;
2092 	unsigned long offset;
2093 	ext4_group_t block_group;
2094 };
2095 
2096 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2097 {
2098 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2099 }
2100 
2101 /*
2102  * This structure is stuffed into the struct file's private_data field
2103  * for directories.  It is where we put information so that we can do
2104  * readdir operations in hash tree order.
2105  */
2106 struct dir_private_info {
2107 	struct rb_root	root;
2108 	struct rb_node	*curr_node;
2109 	struct fname	*extra_fname;
2110 	loff_t		last_pos;
2111 	__u32		curr_hash;
2112 	__u32		curr_minor_hash;
2113 	__u32		next_hash;
2114 };
2115 
2116 /* calculate the first block number of the group */
2117 static inline ext4_fsblk_t
2118 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2119 {
2120 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2121 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2122 }
2123 
2124 /*
2125  * Special error return code only used by dx_probe() and its callers.
2126  */
2127 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2128 
2129 /*
2130  * Timeout and state flag for lazy initialization inode thread.
2131  */
2132 #define EXT4_DEF_LI_WAIT_MULT			10
2133 #define EXT4_DEF_LI_MAX_START_DELAY		5
2134 #define EXT4_LAZYINIT_QUIT			0x0001
2135 #define EXT4_LAZYINIT_RUNNING			0x0002
2136 
2137 /*
2138  * Lazy inode table initialization info
2139  */
2140 struct ext4_lazy_init {
2141 	unsigned long		li_state;
2142 	struct list_head	li_request_list;
2143 	struct mutex		li_list_mtx;
2144 };
2145 
2146 struct ext4_li_request {
2147 	struct super_block	*lr_super;
2148 	struct ext4_sb_info	*lr_sbi;
2149 	ext4_group_t		lr_next_group;
2150 	struct list_head	lr_request;
2151 	unsigned long		lr_next_sched;
2152 	unsigned long		lr_timeout;
2153 };
2154 
2155 struct ext4_features {
2156 	struct kobject f_kobj;
2157 	struct completion f_kobj_unregister;
2158 };
2159 
2160 /*
2161  * This structure will be used for multiple mount protection. It will be
2162  * written into the block number saved in the s_mmp_block field in the
2163  * superblock. Programs that check MMP should assume that if
2164  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2165  * to use the filesystem, regardless of how old the timestamp is.
2166  */
2167 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2168 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2169 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2170 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2171 
2172 struct mmp_struct {
2173 	__le32	mmp_magic;		/* Magic number for MMP */
2174 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2175 
2176 	/*
2177 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2178 	 * purposes and do not affect the correctness of the algorithm
2179 	 */
2180 	__le64	mmp_time;		/* Time last updated */
2181 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2182 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2183 
2184 	/*
2185 	 * mmp_check_interval is used to verify if the MMP block has been
2186 	 * updated on the block device. The value is updated based on the
2187 	 * maximum time to write the MMP block during an update cycle.
2188 	 */
2189 	__le16	mmp_check_interval;
2190 
2191 	__le16	mmp_pad1;
2192 	__le32	mmp_pad2[226];
2193 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2194 };
2195 
2196 /* arguments passed to the mmp thread */
2197 struct mmpd_data {
2198 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2199 	struct super_block *sb;  /* super block of the fs */
2200 };
2201 
2202 /*
2203  * Check interval multiplier
2204  * The MMP block is written every update interval and initially checked every
2205  * update interval x the multiplier (the value is then adapted based on the
2206  * write latency). The reason is that writes can be delayed under load and we
2207  * don't want readers to incorrectly assume that the filesystem is no longer
2208  * in use.
2209  */
2210 #define EXT4_MMP_CHECK_MULT		2UL
2211 
2212 /*
2213  * Minimum interval for MMP checking in seconds.
2214  */
2215 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2216 
2217 /*
2218  * Maximum interval for MMP checking in seconds.
2219  */
2220 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2221 
2222 /*
2223  * Function prototypes
2224  */
2225 
2226 /*
2227  * Ok, these declarations are also in <linux/kernel.h> but none of the
2228  * ext4 source programs needs to include it so they are duplicated here.
2229  */
2230 # define NORET_TYPE	/**/
2231 # define ATTRIB_NORET	__attribute__((noreturn))
2232 # define NORET_AND	noreturn,
2233 
2234 /* bitmap.c */
2235 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2236 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2237 				struct ext4_group_desc *gdp,
2238 				struct buffer_head *bh, int sz);
2239 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2240 				  struct ext4_group_desc *gdp,
2241 				  struct buffer_head *bh, int sz);
2242 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2243 				struct ext4_group_desc *gdp,
2244 				struct buffer_head *bh);
2245 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2246 				  struct ext4_group_desc *gdp,
2247 				  struct buffer_head *bh);
2248 
2249 /* balloc.c */
2250 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2251 					 ext4_fsblk_t blocknr,
2252 					 ext4_group_t *blockgrpp,
2253 					 ext4_grpblk_t *offsetp);
2254 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2255 					  ext4_fsblk_t block);
2256 
2257 extern unsigned int ext4_block_group(struct super_block *sb,
2258 			ext4_fsblk_t blocknr);
2259 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2260 			ext4_fsblk_t blocknr);
2261 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2262 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2263 			ext4_group_t group);
2264 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2265 					 ext4_fsblk_t goal,
2266 					 unsigned int flags,
2267 					 unsigned long *count,
2268 					 int *errp);
2269 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2270 				    s64 nclusters, unsigned int flags);
2271 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2272 extern void ext4_check_blocks_bitmap(struct super_block *);
2273 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2274 						    ext4_group_t block_group,
2275 						    struct buffer_head ** bh);
2276 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2277 
2278 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2279 						ext4_group_t block_group);
2280 extern int ext4_wait_block_bitmap(struct super_block *sb,
2281 				  ext4_group_t block_group,
2282 				  struct buffer_head *bh);
2283 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2284 						  ext4_group_t block_group);
2285 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2286 					      ext4_group_t block_group,
2287 					      struct ext4_group_desc *gdp);
2288 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2289 
2290 static inline bool ext4_encrypted_inode(struct inode *inode)
2291 {
2292 	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
2293 }
2294 
2295 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2296 static inline int ext4_fname_setup_filename(struct inode *dir,
2297 			const struct qstr *iname,
2298 			int lookup, struct ext4_filename *fname)
2299 {
2300 	struct fscrypt_name name;
2301 	int err;
2302 
2303 	memset(fname, 0, sizeof(struct ext4_filename));
2304 
2305 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2306 
2307 	fname->usr_fname = name.usr_fname;
2308 	fname->disk_name = name.disk_name;
2309 	fname->hinfo.hash = name.hash;
2310 	fname->hinfo.minor_hash = name.minor_hash;
2311 	fname->crypto_buf = name.crypto_buf;
2312 	return err;
2313 }
2314 
2315 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2316 {
2317 	struct fscrypt_name name;
2318 
2319 	name.crypto_buf = fname->crypto_buf;
2320 	fscrypt_free_filename(&name);
2321 
2322 	fname->crypto_buf.name = NULL;
2323 	fname->usr_fname = NULL;
2324 	fname->disk_name.name = NULL;
2325 }
2326 #else
2327 static inline int ext4_fname_setup_filename(struct inode *dir,
2328 		const struct qstr *iname,
2329 		int lookup, struct ext4_filename *fname)
2330 {
2331 	fname->usr_fname = iname;
2332 	fname->disk_name.name = (unsigned char *) iname->name;
2333 	fname->disk_name.len = iname->len;
2334 	return 0;
2335 }
2336 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2337 
2338 #endif
2339 
2340 /* dir.c */
2341 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2342 				  struct file *,
2343 				  struct ext4_dir_entry_2 *,
2344 				  struct buffer_head *, char *, int,
2345 				  unsigned int);
2346 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2347 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2348 					(de), (bh), (buf), (size), (offset)))
2349 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2350 				__u32 minor_hash,
2351 				struct ext4_dir_entry_2 *dirent,
2352 				struct fscrypt_str *ent_name);
2353 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2354 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2355 			     struct buffer_head *bh,
2356 			     void *buf, int buf_size,
2357 			     struct ext4_filename *fname,
2358 			     struct ext4_dir_entry_2 **dest_de);
2359 int ext4_insert_dentry(struct inode *dir,
2360 		       struct inode *inode,
2361 		       struct ext4_dir_entry_2 *de,
2362 		       int buf_size,
2363 		       struct ext4_filename *fname);
2364 static inline void ext4_update_dx_flag(struct inode *inode)
2365 {
2366 	if (!ext4_has_feature_dir_index(inode->i_sb))
2367 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2368 }
2369 static unsigned char ext4_filetype_table[] = {
2370 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2371 };
2372 
2373 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2374 {
2375 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2376 		return DT_UNKNOWN;
2377 
2378 	return ext4_filetype_table[filetype];
2379 }
2380 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2381 			     void *buf, int buf_size);
2382 
2383 /* fsync.c */
2384 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2385 
2386 /* hash.c */
2387 extern int ext4fs_dirhash(const char *name, int len, struct
2388 			  dx_hash_info *hinfo);
2389 
2390 /* ialloc.c */
2391 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2392 				      const struct qstr *qstr, __u32 goal,
2393 				      uid_t *owner, int handle_type,
2394 				      unsigned int line_no, int nblocks);
2395 
2396 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner) \
2397 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2398 			 0, 0, 0)
2399 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2400 				    type, nblocks)		    \
2401 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2402 			 (type), __LINE__, (nblocks))
2403 
2404 
2405 extern void ext4_free_inode(handle_t *, struct inode *);
2406 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2407 extern unsigned long ext4_count_free_inodes(struct super_block *);
2408 extern unsigned long ext4_count_dirs(struct super_block *);
2409 extern void ext4_check_inodes_bitmap(struct super_block *);
2410 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2411 extern int ext4_init_inode_table(struct super_block *sb,
2412 				 ext4_group_t group, int barrier);
2413 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2414 
2415 /* mballoc.c */
2416 extern const struct file_operations ext4_seq_mb_groups_fops;
2417 extern long ext4_mb_stats;
2418 extern long ext4_mb_max_to_scan;
2419 extern int ext4_mb_init(struct super_block *);
2420 extern int ext4_mb_release(struct super_block *);
2421 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2422 				struct ext4_allocation_request *, int *);
2423 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2424 extern void ext4_discard_preallocations(struct inode *);
2425 extern int __init ext4_init_mballoc(void);
2426 extern void ext4_exit_mballoc(void);
2427 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2428 			     struct buffer_head *bh, ext4_fsblk_t block,
2429 			     unsigned long count, int flags);
2430 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2431 				   ext4_group_t ngroups);
2432 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2433 		ext4_group_t i, struct ext4_group_desc *desc);
2434 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2435 				ext4_fsblk_t block, unsigned long count);
2436 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2437 
2438 /* inode.c */
2439 int ext4_inode_is_fast_symlink(struct inode *inode);
2440 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2441 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2442 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2443 			     struct buffer_head *bh_result, int create);
2444 int ext4_get_block(struct inode *inode, sector_t iblock,
2445 		   struct buffer_head *bh_result, int create);
2446 int ext4_dio_get_block(struct inode *inode, sector_t iblock,
2447 		       struct buffer_head *bh_result, int create);
2448 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2449 			   struct buffer_head *bh, int create);
2450 int ext4_walk_page_buffers(handle_t *handle,
2451 			   struct buffer_head *head,
2452 			   unsigned from,
2453 			   unsigned to,
2454 			   int *partial,
2455 			   int (*fn)(handle_t *handle,
2456 				     struct buffer_head *bh));
2457 int do_journal_get_write_access(handle_t *handle,
2458 				struct buffer_head *bh);
2459 #define FALL_BACK_TO_NONDELALLOC 1
2460 #define CONVERT_INLINE_DATA	 2
2461 
2462 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2463 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
2464 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2465 extern int  ext4_setattr(struct dentry *, struct iattr *);
2466 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2467 extern void ext4_evict_inode(struct inode *);
2468 extern void ext4_clear_inode(struct inode *);
2469 extern int  ext4_sync_inode(handle_t *, struct inode *);
2470 extern void ext4_dirty_inode(struct inode *, int);
2471 extern int ext4_change_inode_journal_flag(struct inode *, int);
2472 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2473 extern int ext4_inode_attach_jinode(struct inode *inode);
2474 extern int ext4_can_truncate(struct inode *inode);
2475 extern int ext4_truncate(struct inode *);
2476 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2477 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2478 extern void ext4_set_inode_flags(struct inode *);
2479 extern void ext4_get_inode_flags(struct ext4_inode_info *);
2480 extern int ext4_alloc_da_blocks(struct inode *inode);
2481 extern void ext4_set_aops(struct inode *inode);
2482 extern int ext4_writepage_trans_blocks(struct inode *);
2483 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2484 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2485 			     loff_t lstart, loff_t lend);
2486 extern int ext4_page_mkwrite(struct vm_fault *vmf);
2487 extern int ext4_filemap_fault(struct vm_fault *vmf);
2488 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2489 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2490 extern void ext4_da_update_reserve_space(struct inode *inode,
2491 					int used, int quota_claim);
2492 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2493 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2494 extern int ext4_get_next_extent(struct inode *inode, ext4_lblk_t lblk,
2495 				unsigned int map_len,
2496 				struct extent_status *result);
2497 
2498 /* indirect.c */
2499 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2500 				struct ext4_map_blocks *map, int flags);
2501 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2502 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2503 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2504 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2505 				 ext4_lblk_t start, ext4_lblk_t end);
2506 
2507 /* ioctl.c */
2508 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2509 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2510 
2511 /* migrate.c */
2512 extern int ext4_ext_migrate(struct inode *);
2513 extern int ext4_ind_migrate(struct inode *inode);
2514 
2515 /* namei.c */
2516 extern int ext4_dirent_csum_verify(struct inode *inode,
2517 				   struct ext4_dir_entry *dirent);
2518 extern int ext4_orphan_add(handle_t *, struct inode *);
2519 extern int ext4_orphan_del(handle_t *, struct inode *);
2520 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2521 				__u32 start_minor_hash, __u32 *next_hash);
2522 extern int ext4_search_dir(struct buffer_head *bh,
2523 			   char *search_buf,
2524 			   int buf_size,
2525 			   struct inode *dir,
2526 			   struct ext4_filename *fname,
2527 			   const struct qstr *d_name,
2528 			   unsigned int offset,
2529 			   struct ext4_dir_entry_2 **res_dir);
2530 extern int ext4_generic_delete_entry(handle_t *handle,
2531 				     struct inode *dir,
2532 				     struct ext4_dir_entry_2 *de_del,
2533 				     struct buffer_head *bh,
2534 				     void *entry_buf,
2535 				     int buf_size,
2536 				     int csum_size);
2537 extern bool ext4_empty_dir(struct inode *inode);
2538 
2539 /* resize.c */
2540 extern int ext4_group_add(struct super_block *sb,
2541 				struct ext4_new_group_data *input);
2542 extern int ext4_group_extend(struct super_block *sb,
2543 				struct ext4_super_block *es,
2544 				ext4_fsblk_t n_blocks_count);
2545 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2546 
2547 /* super.c */
2548 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2549 extern int ext4_calculate_overhead(struct super_block *sb);
2550 extern void ext4_superblock_csum_set(struct super_block *sb);
2551 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2552 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2553 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2554 				    ext4_group_t ngroup);
2555 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2556 				     char nbuf[16]);
2557 
2558 extern __printf(4, 5)
2559 void __ext4_error(struct super_block *, const char *, unsigned int,
2560 		  const char *, ...);
2561 extern __printf(5, 6)
2562 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2563 		      const char *, ...);
2564 extern __printf(5, 6)
2565 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2566 		     const char *, ...);
2567 extern void __ext4_std_error(struct super_block *, const char *,
2568 			     unsigned int, int);
2569 extern __printf(4, 5)
2570 void __ext4_abort(struct super_block *, const char *, unsigned int,
2571 		  const char *, ...);
2572 extern __printf(4, 5)
2573 void __ext4_warning(struct super_block *, const char *, unsigned int,
2574 		    const char *, ...);
2575 extern __printf(4, 5)
2576 void __ext4_warning_inode(const struct inode *inode, const char *function,
2577 			  unsigned int line, const char *fmt, ...);
2578 extern __printf(3, 4)
2579 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2580 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2581 			   const char *, unsigned int, const char *);
2582 extern __printf(7, 8)
2583 void __ext4_grp_locked_error(const char *, unsigned int,
2584 			     struct super_block *, ext4_group_t,
2585 			     unsigned long, ext4_fsblk_t,
2586 			     const char *, ...);
2587 
2588 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2589 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2590 
2591 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
2592 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2593 
2594 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2595 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2596 
2597 #ifdef CONFIG_PRINTK
2598 
2599 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2600 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2601 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2602 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2603 #define ext4_error(sb, fmt, ...)					\
2604 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2605 #define ext4_abort(sb, fmt, ...)					\
2606 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2607 #define ext4_warning(sb, fmt, ...)					\
2608 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2609 #define ext4_warning_inode(inode, fmt, ...)				\
2610 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2611 #define ext4_msg(sb, level, fmt, ...)				\
2612 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2613 #define dump_mmp_msg(sb, mmp, msg)					\
2614 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2615 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2616 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2617 				fmt, ##__VA_ARGS__)
2618 
2619 #else
2620 
2621 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2622 do {									\
2623 	no_printk(fmt, ##__VA_ARGS__);					\
2624 	__ext4_error_inode(inode, "", 0, block, " ");			\
2625 } while (0)
2626 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2627 do {									\
2628 	no_printk(fmt, ##__VA_ARGS__);					\
2629 	__ext4_error_file(file, "", 0, block, " ");			\
2630 } while (0)
2631 #define ext4_error(sb, fmt, ...)					\
2632 do {									\
2633 	no_printk(fmt, ##__VA_ARGS__);					\
2634 	__ext4_error(sb, "", 0, " ");					\
2635 } while (0)
2636 #define ext4_abort(sb, fmt, ...)					\
2637 do {									\
2638 	no_printk(fmt, ##__VA_ARGS__);					\
2639 	__ext4_abort(sb, "", 0, " ");					\
2640 } while (0)
2641 #define ext4_warning(sb, fmt, ...)					\
2642 do {									\
2643 	no_printk(fmt, ##__VA_ARGS__);					\
2644 	__ext4_warning(sb, "", 0, " ");					\
2645 } while (0)
2646 #define ext4_warning_inode(inode, fmt, ...)				\
2647 do {									\
2648 	no_printk(fmt, ##__VA_ARGS__);					\
2649 	__ext4_warning_inode(inode, "", 0, " ");			\
2650 } while (0)
2651 #define ext4_msg(sb, level, fmt, ...)					\
2652 do {									\
2653 	no_printk(fmt, ##__VA_ARGS__);					\
2654 	__ext4_msg(sb, "", " ");					\
2655 } while (0)
2656 #define dump_mmp_msg(sb, mmp, msg)					\
2657 	__dump_mmp_msg(sb, mmp, "", 0, "")
2658 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2659 do {									\
2660 	no_printk(fmt, ##__VA_ARGS__);				\
2661 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2662 } while (0)
2663 
2664 #endif
2665 
2666 extern void ext4_update_dynamic_rev(struct super_block *sb);
2667 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2668 					__u32 compat);
2669 extern int ext4_update_rocompat_feature(handle_t *handle,
2670 					struct super_block *sb,	__u32 rocompat);
2671 extern int ext4_update_incompat_feature(handle_t *handle,
2672 					struct super_block *sb,	__u32 incompat);
2673 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2674 				      struct ext4_group_desc *bg);
2675 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2676 				      struct ext4_group_desc *bg);
2677 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2678 				     struct ext4_group_desc *bg);
2679 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2680 				      struct ext4_group_desc *bg);
2681 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2682 				 struct ext4_group_desc *bg);
2683 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2684 				struct ext4_group_desc *bg);
2685 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2686 				   struct ext4_group_desc *bg);
2687 extern void ext4_block_bitmap_set(struct super_block *sb,
2688 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2689 extern void ext4_inode_bitmap_set(struct super_block *sb,
2690 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2691 extern void ext4_inode_table_set(struct super_block *sb,
2692 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2693 extern void ext4_free_group_clusters_set(struct super_block *sb,
2694 					 struct ext4_group_desc *bg,
2695 					 __u32 count);
2696 extern void ext4_free_inodes_set(struct super_block *sb,
2697 				struct ext4_group_desc *bg, __u32 count);
2698 extern void ext4_used_dirs_set(struct super_block *sb,
2699 				struct ext4_group_desc *bg, __u32 count);
2700 extern void ext4_itable_unused_set(struct super_block *sb,
2701 				   struct ext4_group_desc *bg, __u32 count);
2702 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2703 				       struct ext4_group_desc *gdp);
2704 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2705 				     struct ext4_group_desc *gdp);
2706 extern int ext4_register_li_request(struct super_block *sb,
2707 				    ext4_group_t first_not_zeroed);
2708 
2709 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2710 {
2711 	return ext4_has_feature_gdt_csum(sb) ||
2712 	       EXT4_SB(sb)->s_chksum_driver != NULL;
2713 }
2714 
2715 static inline int ext4_has_metadata_csum(struct super_block *sb)
2716 {
2717 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2718 		     !EXT4_SB(sb)->s_chksum_driver);
2719 
2720 	return (EXT4_SB(sb)->s_chksum_driver != NULL);
2721 }
2722 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2723 {
2724 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2725 		le32_to_cpu(es->s_blocks_count_lo);
2726 }
2727 
2728 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2729 {
2730 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2731 		le32_to_cpu(es->s_r_blocks_count_lo);
2732 }
2733 
2734 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2735 {
2736 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2737 		le32_to_cpu(es->s_free_blocks_count_lo);
2738 }
2739 
2740 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2741 					 ext4_fsblk_t blk)
2742 {
2743 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2744 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2745 }
2746 
2747 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2748 					      ext4_fsblk_t blk)
2749 {
2750 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2751 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2752 }
2753 
2754 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2755 					   ext4_fsblk_t blk)
2756 {
2757 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2758 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2759 }
2760 
2761 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2762 {
2763 	if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2764 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2765 			le32_to_cpu(raw_inode->i_size_lo);
2766 	else
2767 		return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2768 }
2769 
2770 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2771 {
2772 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2773 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2774 }
2775 
2776 static inline
2777 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2778 					    ext4_group_t group)
2779 {
2780 	 struct ext4_group_info ***grp_info;
2781 	 long indexv, indexh;
2782 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2783 	 grp_info = EXT4_SB(sb)->s_group_info;
2784 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2785 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2786 	 return grp_info[indexv][indexh];
2787 }
2788 
2789 /*
2790  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2791  * the locking protocol documented in the comments of ext4_group_add()
2792  * in resize.c
2793  */
2794 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2795 {
2796 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2797 
2798 	smp_rmb();
2799 	return ngroups;
2800 }
2801 
2802 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2803 					     ext4_group_t block_group)
2804 {
2805 	return block_group >> sbi->s_log_groups_per_flex;
2806 }
2807 
2808 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2809 {
2810 	return 1 << sbi->s_log_groups_per_flex;
2811 }
2812 
2813 #define ext4_std_error(sb, errno)				\
2814 do {								\
2815 	if ((errno))						\
2816 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2817 } while (0)
2818 
2819 #ifdef CONFIG_SMP
2820 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2821  * counters. So we need to make sure we have free clusters more
2822  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2823  */
2824 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2825 #else
2826 #define EXT4_FREECLUSTERS_WATERMARK 0
2827 #endif
2828 
2829 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2830 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2831 {
2832 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2833 		     !inode_is_locked(inode));
2834 	down_write(&EXT4_I(inode)->i_data_sem);
2835 	if (newsize > EXT4_I(inode)->i_disksize)
2836 		EXT4_I(inode)->i_disksize = newsize;
2837 	up_write(&EXT4_I(inode)->i_data_sem);
2838 }
2839 
2840 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2841 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2842 {
2843 	int changed = 0;
2844 
2845 	if (newsize > inode->i_size) {
2846 		i_size_write(inode, newsize);
2847 		changed = 1;
2848 	}
2849 	if (newsize > EXT4_I(inode)->i_disksize) {
2850 		ext4_update_i_disksize(inode, newsize);
2851 		changed |= 2;
2852 	}
2853 	return changed;
2854 }
2855 
2856 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2857 				      loff_t len);
2858 
2859 struct ext4_group_info {
2860 	unsigned long   bb_state;
2861 	struct rb_root  bb_free_root;
2862 	ext4_grpblk_t	bb_first_free;	/* first free block */
2863 	ext4_grpblk_t	bb_free;	/* total free blocks */
2864 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2865 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2866 	struct          list_head bb_prealloc_list;
2867 #ifdef DOUBLE_CHECK
2868 	void            *bb_bitmap;
2869 #endif
2870 	struct rw_semaphore alloc_sem;
2871 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2872 					 * regions, index is order.
2873 					 * bb_counters[3] = 5 means
2874 					 * 5 free 8-block regions. */
2875 };
2876 
2877 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2878 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2879 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2880 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2881 
2882 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2883 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2884 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2885 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2886 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2887 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2888 
2889 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2890 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2891 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2892 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2893 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2894 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2895 
2896 #define EXT4_MAX_CONTENTION		8
2897 #define EXT4_CONTENTION_THRESHOLD	2
2898 
2899 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2900 					      ext4_group_t group)
2901 {
2902 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2903 }
2904 
2905 /*
2906  * Returns true if the filesystem is busy enough that attempts to
2907  * access the block group locks has run into contention.
2908  */
2909 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2910 {
2911 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2912 }
2913 
2914 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2915 {
2916 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2917 	if (spin_trylock(lock))
2918 		/*
2919 		 * We're able to grab the lock right away, so drop the
2920 		 * lock contention counter.
2921 		 */
2922 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2923 	else {
2924 		/*
2925 		 * The lock is busy, so bump the contention counter,
2926 		 * and then wait on the spin lock.
2927 		 */
2928 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2929 				  EXT4_MAX_CONTENTION);
2930 		spin_lock(lock);
2931 	}
2932 }
2933 
2934 static inline void ext4_unlock_group(struct super_block *sb,
2935 					ext4_group_t group)
2936 {
2937 	spin_unlock(ext4_group_lock_ptr(sb, group));
2938 }
2939 
2940 /*
2941  * Block validity checking
2942  */
2943 #define ext4_check_indirect_blockref(inode, bh)				\
2944 	ext4_check_blockref(__func__, __LINE__, inode,			\
2945 			    (__le32 *)(bh)->b_data,			\
2946 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2947 
2948 #define ext4_ind_check_inode(inode)					\
2949 	ext4_check_blockref(__func__, __LINE__, inode,			\
2950 			    EXT4_I(inode)->i_data,			\
2951 			    EXT4_NDIR_BLOCKS)
2952 
2953 /*
2954  * Inodes and files operations
2955  */
2956 
2957 /* dir.c */
2958 extern const struct file_operations ext4_dir_operations;
2959 
2960 /* file.c */
2961 extern const struct inode_operations ext4_file_inode_operations;
2962 extern const struct file_operations ext4_file_operations;
2963 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2964 
2965 /* inline.c */
2966 extern int ext4_get_max_inline_size(struct inode *inode);
2967 extern int ext4_find_inline_data_nolock(struct inode *inode);
2968 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2969 				 unsigned int len);
2970 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2971 
2972 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2973 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2974 					 struct inode *inode,
2975 					 loff_t pos, unsigned len,
2976 					 unsigned flags,
2977 					 struct page **pagep);
2978 extern int ext4_write_inline_data_end(struct inode *inode,
2979 				      loff_t pos, unsigned len,
2980 				      unsigned copied,
2981 				      struct page *page);
2982 extern struct buffer_head *
2983 ext4_journalled_write_inline_data(struct inode *inode,
2984 				  unsigned len,
2985 				  struct page *page);
2986 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
2987 					   struct inode *inode,
2988 					   loff_t pos, unsigned len,
2989 					   unsigned flags,
2990 					   struct page **pagep,
2991 					   void **fsdata);
2992 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
2993 					 unsigned len, unsigned copied,
2994 					 struct page *page);
2995 extern int ext4_try_add_inline_entry(handle_t *handle,
2996 				     struct ext4_filename *fname,
2997 				     struct inode *dir, struct inode *inode);
2998 extern int ext4_try_create_inline_dir(handle_t *handle,
2999 				      struct inode *parent,
3000 				      struct inode *inode);
3001 extern int ext4_read_inline_dir(struct file *filp,
3002 				struct dir_context *ctx,
3003 				int *has_inline_data);
3004 extern int htree_inlinedir_to_tree(struct file *dir_file,
3005 				   struct inode *dir, ext4_lblk_t block,
3006 				   struct dx_hash_info *hinfo,
3007 				   __u32 start_hash, __u32 start_minor_hash,
3008 				   int *has_inline_data);
3009 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3010 					struct ext4_filename *fname,
3011 					const struct qstr *d_name,
3012 					struct ext4_dir_entry_2 **res_dir,
3013 					int *has_inline_data);
3014 extern int ext4_delete_inline_entry(handle_t *handle,
3015 				    struct inode *dir,
3016 				    struct ext4_dir_entry_2 *de_del,
3017 				    struct buffer_head *bh,
3018 				    int *has_inline_data);
3019 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3020 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3021 					struct ext4_dir_entry_2 **parent_de,
3022 					int *retval);
3023 extern int ext4_inline_data_fiemap(struct inode *inode,
3024 				   struct fiemap_extent_info *fieinfo,
3025 				   int *has_inline, __u64 start, __u64 len);
3026 extern int ext4_try_to_evict_inline_data(handle_t *handle,
3027 					 struct inode *inode,
3028 					 int needed);
3029 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3030 
3031 extern int ext4_convert_inline_data(struct inode *inode);
3032 
3033 static inline int ext4_has_inline_data(struct inode *inode)
3034 {
3035 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3036 	       EXT4_I(inode)->i_inline_off;
3037 }
3038 
3039 /* namei.c */
3040 extern const struct inode_operations ext4_dir_inode_operations;
3041 extern const struct inode_operations ext4_special_inode_operations;
3042 extern struct dentry *ext4_get_parent(struct dentry *child);
3043 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3044 				 struct ext4_dir_entry_2 *de,
3045 				 int blocksize, int csum_size,
3046 				 unsigned int parent_ino, int dotdot_real_len);
3047 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
3048 				   unsigned int blocksize);
3049 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
3050 					 struct inode *inode,
3051 					 struct buffer_head *bh);
3052 #define S_SHIFT 12
3053 static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
3054 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3055 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3056 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3057 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3058 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3059 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3060 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3061 };
3062 
3063 static inline void ext4_set_de_type(struct super_block *sb,
3064 				struct ext4_dir_entry_2 *de,
3065 				umode_t mode) {
3066 	if (ext4_has_feature_filetype(sb))
3067 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3068 }
3069 
3070 /* readpages.c */
3071 extern int ext4_mpage_readpages(struct address_space *mapping,
3072 				struct list_head *pages, struct page *page,
3073 				unsigned nr_pages);
3074 
3075 /* symlink.c */
3076 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3077 extern const struct inode_operations ext4_symlink_inode_operations;
3078 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3079 
3080 /* sysfs.c */
3081 extern int ext4_register_sysfs(struct super_block *sb);
3082 extern void ext4_unregister_sysfs(struct super_block *sb);
3083 extern int __init ext4_init_sysfs(void);
3084 extern void ext4_exit_sysfs(void);
3085 
3086 /* block_validity */
3087 extern void ext4_release_system_zone(struct super_block *sb);
3088 extern int ext4_setup_system_zone(struct super_block *sb);
3089 extern int __init ext4_init_system_zone(void);
3090 extern void ext4_exit_system_zone(void);
3091 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3092 				 ext4_fsblk_t start_blk,
3093 				 unsigned int count);
3094 extern int ext4_check_blockref(const char *, unsigned int,
3095 			       struct inode *, __le32 *, unsigned int);
3096 
3097 /* extents.c */
3098 struct ext4_ext_path;
3099 struct ext4_extent;
3100 
3101 /*
3102  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3103  * __le32.
3104  */
3105 #define EXT_MAX_BLOCKS	0xffffffff
3106 
3107 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
3108 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
3109 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3110 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3111 			       struct ext4_map_blocks *map, int flags);
3112 extern int ext4_ext_truncate(handle_t *, struct inode *);
3113 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3114 				 ext4_lblk_t end);
3115 extern void ext4_ext_init(struct super_block *);
3116 extern void ext4_ext_release(struct super_block *);
3117 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3118 			  loff_t len);
3119 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3120 					  loff_t offset, ssize_t len);
3121 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3122 			   struct ext4_map_blocks *map, int flags);
3123 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
3124 					 ext4_lblk_t lblocks);
3125 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3126 						   int num,
3127 						   struct ext4_ext_path *path);
3128 extern int ext4_can_extents_be_merged(struct inode *inode,
3129 				      struct ext4_extent *ex1,
3130 				      struct ext4_extent *ex2);
3131 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3132 				  struct ext4_ext_path **,
3133 				  struct ext4_extent *, int);
3134 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3135 					      struct ext4_ext_path **,
3136 					      int flags);
3137 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3138 extern int ext4_ext_check_inode(struct inode *inode);
3139 extern int ext4_find_delalloc_range(struct inode *inode,
3140 				    ext4_lblk_t lblk_start,
3141 				    ext4_lblk_t lblk_end);
3142 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
3143 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3144 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3145 			__u64 start, __u64 len);
3146 extern int ext4_ext_precache(struct inode *inode);
3147 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
3148 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
3149 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3150 				struct inode *inode2, ext4_lblk_t lblk1,
3151 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3152 			     int mark_unwritten,int *err);
3153 
3154 /* move_extent.c */
3155 extern void ext4_double_down_write_data_sem(struct inode *first,
3156 					    struct inode *second);
3157 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3158 					  struct inode *donor_inode);
3159 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3160 			     __u64 start_orig, __u64 start_donor,
3161 			     __u64 len, __u64 *moved_len);
3162 
3163 /* page-io.c */
3164 extern int __init ext4_init_pageio(void);
3165 extern void ext4_exit_pageio(void);
3166 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3167 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3168 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3169 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3170 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3171 				struct writeback_control *wbc);
3172 extern void ext4_end_io_rsv_work(struct work_struct *work);
3173 extern void ext4_io_submit(struct ext4_io_submit *io);
3174 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3175 			       struct page *page,
3176 			       int len,
3177 			       struct writeback_control *wbc,
3178 			       bool keep_towrite);
3179 
3180 /* mmp.c */
3181 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3182 
3183 /*
3184  * Add new method to test whether block and inode bitmaps are properly
3185  * initialized. With uninit_bg reading the block from disk is not enough
3186  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3187  */
3188 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3189 
3190 static inline int bitmap_uptodate(struct buffer_head *bh)
3191 {
3192 	return (buffer_uptodate(bh) &&
3193 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3194 }
3195 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3196 {
3197 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3198 }
3199 
3200 /*
3201  * Disable DIO read nolock optimization, so new dioreaders will be forced
3202  * to grab i_mutex
3203  */
3204 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
3205 {
3206 	ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3207 	smp_mb();
3208 }
3209 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
3210 {
3211 	smp_mb();
3212 	ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3213 }
3214 
3215 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3216 
3217 /* For ioend & aio unwritten conversion wait queues */
3218 #define EXT4_WQ_HASH_SZ		37
3219 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3220 					    EXT4_WQ_HASH_SZ])
3221 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3222 
3223 extern int ext4_resize_begin(struct super_block *sb);
3224 extern void ext4_resize_end(struct super_block *sb);
3225 
3226 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3227 					      struct ext4_io_end *io_end)
3228 {
3229 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3230 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3231 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3232 	}
3233 }
3234 
3235 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3236 {
3237 	struct inode *inode = io_end->inode;
3238 
3239 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3240 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3241 		/* Wake up anyone waiting on unwritten extent conversion */
3242 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3243 			wake_up_all(ext4_ioend_wq(inode));
3244 	}
3245 }
3246 
3247 extern const struct iomap_ops ext4_iomap_ops;
3248 
3249 #endif	/* __KERNEL__ */
3250 
3251 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3252 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3253 
3254 #endif	/* _EXT4_H */
3255