xref: /linux/fs/ext4/ext4.h (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
1 /*
2  *  ext4.h
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/include/linux/minix_fs.h
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  */
15 
16 #ifndef _EXT4_H
17 #define _EXT4_H
18 
19 #include <linux/types.h>
20 #include <linux/blkdev.h>
21 #include <linux/magic.h>
22 #include <linux/jbd2.h>
23 #include <linux/quota.h>
24 #include <linux/rwsem.h>
25 #include <linux/rbtree.h>
26 #include <linux/seqlock.h>
27 #include <linux/mutex.h>
28 #include <linux/timer.h>
29 #include <linux/wait.h>
30 #include <linux/blockgroup_lock.h>
31 #include <linux/percpu_counter.h>
32 #include <linux/ratelimit.h>
33 #include <crypto/hash.h>
34 #include <linux/falloc.h>
35 #ifdef __KERNEL__
36 #include <linux/compat.h>
37 #endif
38 
39 /*
40  * The fourth extended filesystem constants/structures
41  */
42 
43 /*
44  * Define EXT4FS_DEBUG to produce debug messages
45  */
46 #undef EXT4FS_DEBUG
47 
48 /*
49  * Debug code
50  */
51 #ifdef EXT4FS_DEBUG
52 #define ext4_debug(f, a...)						\
53 	do {								\
54 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
55 			__FILE__, __LINE__, __func__);			\
56 		printk(KERN_DEBUG f, ## a);				\
57 	} while (0)
58 #else
59 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
60 #endif
61 
62 /*
63  * Turn on EXT_DEBUG to get lots of info about extents operations.
64  */
65 #define EXT_DEBUG__
66 #ifdef EXT_DEBUG
67 #define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
68 #else
69 #define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
70 #endif
71 
72 /* data type for block offset of block group */
73 typedef int ext4_grpblk_t;
74 
75 /* data type for filesystem-wide blocks number */
76 typedef unsigned long long ext4_fsblk_t;
77 
78 /* data type for file logical block number */
79 typedef __u32 ext4_lblk_t;
80 
81 /* data type for block group number */
82 typedef unsigned int ext4_group_t;
83 
84 enum SHIFT_DIRECTION {
85 	SHIFT_LEFT = 0,
86 	SHIFT_RIGHT,
87 };
88 
89 /*
90  * Flags used in mballoc's allocation_context flags field.
91  *
92  * Also used to show what's going on for debugging purposes when the
93  * flag field is exported via the traceport interface
94  */
95 
96 /* prefer goal again. length */
97 #define EXT4_MB_HINT_MERGE		0x0001
98 /* blocks already reserved */
99 #define EXT4_MB_HINT_RESERVED		0x0002
100 /* metadata is being allocated */
101 #define EXT4_MB_HINT_METADATA		0x0004
102 /* first blocks in the file */
103 #define EXT4_MB_HINT_FIRST		0x0008
104 /* search for the best chunk */
105 #define EXT4_MB_HINT_BEST		0x0010
106 /* data is being allocated */
107 #define EXT4_MB_HINT_DATA		0x0020
108 /* don't preallocate (for tails) */
109 #define EXT4_MB_HINT_NOPREALLOC		0x0040
110 /* allocate for locality group */
111 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
112 /* allocate goal blocks or none */
113 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
114 /* goal is meaningful */
115 #define EXT4_MB_HINT_TRY_GOAL		0x0200
116 /* blocks already pre-reserved by delayed allocation */
117 #define EXT4_MB_DELALLOC_RESERVED	0x0400
118 /* We are doing stream allocation */
119 #define EXT4_MB_STREAM_ALLOC		0x0800
120 /* Use reserved root blocks if needed */
121 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
122 /* Use blocks from reserved pool */
123 #define EXT4_MB_USE_RESERVED		0x2000
124 
125 struct ext4_allocation_request {
126 	/* target inode for block we're allocating */
127 	struct inode *inode;
128 	/* how many blocks we want to allocate */
129 	unsigned int len;
130 	/* logical block in target inode */
131 	ext4_lblk_t logical;
132 	/* the closest logical allocated block to the left */
133 	ext4_lblk_t lleft;
134 	/* the closest logical allocated block to the right */
135 	ext4_lblk_t lright;
136 	/* phys. target (a hint) */
137 	ext4_fsblk_t goal;
138 	/* phys. block for the closest logical allocated block to the left */
139 	ext4_fsblk_t pleft;
140 	/* phys. block for the closest logical allocated block to the right */
141 	ext4_fsblk_t pright;
142 	/* flags. see above EXT4_MB_HINT_* */
143 	unsigned int flags;
144 };
145 
146 /*
147  * Logical to physical block mapping, used by ext4_map_blocks()
148  *
149  * This structure is used to pass requests into ext4_map_blocks() as
150  * well as to store the information returned by ext4_map_blocks().  It
151  * takes less room on the stack than a struct buffer_head.
152  */
153 #define EXT4_MAP_NEW		(1 << BH_New)
154 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
155 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
156 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
157 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
158 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
159 
160 struct ext4_map_blocks {
161 	ext4_fsblk_t m_pblk;
162 	ext4_lblk_t m_lblk;
163 	unsigned int m_len;
164 	unsigned int m_flags;
165 };
166 
167 /*
168  * Flags for ext4_io_end->flags
169  */
170 #define	EXT4_IO_END_UNWRITTEN	0x0001
171 
172 /*
173  * For converting unwritten extents on a work queue. 'handle' is used for
174  * buffered writeback.
175  */
176 typedef struct ext4_io_end {
177 	struct list_head	list;		/* per-file finished IO list */
178 	handle_t		*handle;	/* handle reserved for extent
179 						 * conversion */
180 	struct inode		*inode;		/* file being written to */
181 	struct bio		*bio;		/* Linked list of completed
182 						 * bios covering the extent */
183 	unsigned int		flag;		/* unwritten or not */
184 	loff_t			offset;		/* offset in the file */
185 	ssize_t			size;		/* size of the extent */
186 	atomic_t		count;		/* reference counter */
187 } ext4_io_end_t;
188 
189 struct ext4_io_submit {
190 	int			io_op;
191 	struct bio		*io_bio;
192 	ext4_io_end_t		*io_end;
193 	sector_t		io_next_block;
194 };
195 
196 /*
197  * Special inodes numbers
198  */
199 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
200 #define EXT4_ROOT_INO		 2	/* Root inode */
201 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
202 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
203 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
204 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
205 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
206 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
207 
208 /* First non-reserved inode for old ext4 filesystems */
209 #define EXT4_GOOD_OLD_FIRST_INO	11
210 
211 /*
212  * Maximal count of links to a file
213  */
214 #define EXT4_LINK_MAX		65000
215 
216 /*
217  * Macro-instructions used to manage several block sizes
218  */
219 #define EXT4_MIN_BLOCK_SIZE		1024
220 #define	EXT4_MAX_BLOCK_SIZE		65536
221 #define EXT4_MIN_BLOCK_LOG_SIZE		10
222 #define EXT4_MAX_BLOCK_LOG_SIZE		16
223 #ifdef __KERNEL__
224 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
225 #else
226 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
227 #endif
228 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
229 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
230 					 EXT4_SB(s)->s_cluster_bits)
231 #ifdef __KERNEL__
232 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
233 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
234 #else
235 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
236 #endif
237 #ifdef __KERNEL__
238 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
239 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
240 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
241 #else
242 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
243 				 EXT4_GOOD_OLD_INODE_SIZE : \
244 				 (s)->s_inode_size)
245 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
246 				 EXT4_GOOD_OLD_FIRST_INO : \
247 				 (s)->s_first_ino)
248 #endif
249 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
250 
251 /* Translate a block number to a cluster number */
252 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
253 /* Translate a cluster number to a block number */
254 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
255 /* Translate # of blks to # of clusters */
256 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
257 				 (sbi)->s_cluster_bits)
258 /* Mask out the low bits to get the starting block of the cluster */
259 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
260 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
261 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
262 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
263 /* Get the cluster offset */
264 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
265 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
266 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
267 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
268 
269 /*
270  * Structure of a blocks group descriptor
271  */
272 struct ext4_group_desc
273 {
274 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
275 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
276 	__le32	bg_inode_table_lo;	/* Inodes table block */
277 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
278 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
279 	__le16	bg_used_dirs_count_lo;	/* Directories count */
280 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
281 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
282 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
283 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
284 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
285 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
286 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
287 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
288 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
289 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
290 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
291 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
292 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
293 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
294 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
295 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
296 	__u32   bg_reserved;
297 };
298 
299 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
300 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
301 	 sizeof(__le16))
302 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
303 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
304 	 sizeof(__le16))
305 
306 /*
307  * Structure of a flex block group info
308  */
309 
310 struct flex_groups {
311 	atomic64_t	free_clusters;
312 	atomic_t	free_inodes;
313 	atomic_t	used_dirs;
314 };
315 
316 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
317 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
318 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
319 
320 /*
321  * Macro-instructions used to manage group descriptors
322  */
323 #define EXT4_MIN_DESC_SIZE		32
324 #define EXT4_MIN_DESC_SIZE_64BIT	64
325 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
326 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
327 #ifdef __KERNEL__
328 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
329 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
330 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
331 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
332 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
333 #else
334 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
335 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
336 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
337 #endif
338 
339 /*
340  * Constants relative to the data blocks
341  */
342 #define	EXT4_NDIR_BLOCKS		12
343 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
344 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
345 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
346 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
347 
348 /*
349  * Inode flags
350  */
351 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
352 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
353 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
354 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
355 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
356 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
357 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
358 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
359 /* Reserved for compression usage... */
360 #define EXT4_DIRTY_FL			0x00000100
361 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
362 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
363 	/* nb: was previously EXT2_ECOMPR_FL */
364 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
365 /* End compression flags --- maybe not all used */
366 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
367 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
368 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
369 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
370 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
371 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
372 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
373 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
374 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
375 #define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
376 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
377 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
378 
379 #define EXT4_FL_USER_VISIBLE		0x004BDFFF /* User visible flags */
380 #define EXT4_FL_USER_MODIFIABLE		0x004380FF /* User modifiable flags */
381 
382 /* Flags that should be inherited by new inodes from their parent. */
383 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
384 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
385 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
386 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
387 
388 /* Flags that are appropriate for regular files (all but dir-specific ones). */
389 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
390 
391 /* Flags that are appropriate for non-directories/regular files. */
392 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
393 
394 /* Mask out flags that are inappropriate for the given type of inode. */
395 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
396 {
397 	if (S_ISDIR(mode))
398 		return flags;
399 	else if (S_ISREG(mode))
400 		return flags & EXT4_REG_FLMASK;
401 	else
402 		return flags & EXT4_OTHER_FLMASK;
403 }
404 
405 /*
406  * Inode flags used for atomic set/get
407  */
408 enum {
409 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
410 	EXT4_INODE_UNRM		= 1,	/* Undelete */
411 	EXT4_INODE_COMPR	= 2,	/* Compress file */
412 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
413 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
414 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
415 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
416 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
417 /* Reserved for compression usage... */
418 	EXT4_INODE_DIRTY	= 8,
419 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
420 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
421 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
422 /* End compression flags --- maybe not all used */
423 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
424 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
425 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
426 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
427 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
428 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
429 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
430 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
431 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
432 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
433 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
434 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
435 };
436 
437 /*
438  * Since it's pretty easy to mix up bit numbers and hex values, we use a
439  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
440  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
441  * any extra space in the compiled kernel image, otherwise, the build will fail.
442  * It's important that these values are the same, since we are using
443  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
444  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
445  * values found in ext2, ext3 and ext4 filesystems, and of course the values
446  * defined in e2fsprogs.
447  *
448  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
449  */
450 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
451 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
452 
453 static inline void ext4_check_flag_values(void)
454 {
455 	CHECK_FLAG_VALUE(SECRM);
456 	CHECK_FLAG_VALUE(UNRM);
457 	CHECK_FLAG_VALUE(COMPR);
458 	CHECK_FLAG_VALUE(SYNC);
459 	CHECK_FLAG_VALUE(IMMUTABLE);
460 	CHECK_FLAG_VALUE(APPEND);
461 	CHECK_FLAG_VALUE(NODUMP);
462 	CHECK_FLAG_VALUE(NOATIME);
463 	CHECK_FLAG_VALUE(DIRTY);
464 	CHECK_FLAG_VALUE(COMPRBLK);
465 	CHECK_FLAG_VALUE(NOCOMPR);
466 	CHECK_FLAG_VALUE(ENCRYPT);
467 	CHECK_FLAG_VALUE(INDEX);
468 	CHECK_FLAG_VALUE(IMAGIC);
469 	CHECK_FLAG_VALUE(JOURNAL_DATA);
470 	CHECK_FLAG_VALUE(NOTAIL);
471 	CHECK_FLAG_VALUE(DIRSYNC);
472 	CHECK_FLAG_VALUE(TOPDIR);
473 	CHECK_FLAG_VALUE(HUGE_FILE);
474 	CHECK_FLAG_VALUE(EXTENTS);
475 	CHECK_FLAG_VALUE(EA_INODE);
476 	CHECK_FLAG_VALUE(EOFBLOCKS);
477 	CHECK_FLAG_VALUE(INLINE_DATA);
478 	CHECK_FLAG_VALUE(RESERVED);
479 }
480 
481 /* Used to pass group descriptor data when online resize is done */
482 struct ext4_new_group_input {
483 	__u32 group;		/* Group number for this data */
484 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
485 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
486 	__u64 inode_table;	/* Absolute block number of inode table start */
487 	__u32 blocks_count;	/* Total number of blocks in this group */
488 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
489 	__u16 unused;
490 };
491 
492 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
493 struct compat_ext4_new_group_input {
494 	u32 group;
495 	compat_u64 block_bitmap;
496 	compat_u64 inode_bitmap;
497 	compat_u64 inode_table;
498 	u32 blocks_count;
499 	u16 reserved_blocks;
500 	u16 unused;
501 };
502 #endif
503 
504 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
505 struct ext4_new_group_data {
506 	__u32 group;
507 	__u64 block_bitmap;
508 	__u64 inode_bitmap;
509 	__u64 inode_table;
510 	__u32 blocks_count;
511 	__u16 reserved_blocks;
512 	__u16 unused;
513 	__u32 free_blocks_count;
514 };
515 
516 /* Indexes used to index group tables in ext4_new_group_data */
517 enum {
518 	BLOCK_BITMAP = 0,	/* block bitmap */
519 	INODE_BITMAP,		/* inode bitmap */
520 	INODE_TABLE,		/* inode tables */
521 	GROUP_TABLE_COUNT,
522 };
523 
524 /*
525  * Flags used by ext4_map_blocks()
526  */
527 	/* Allocate any needed blocks and/or convert an unwritten
528 	   extent to be an initialized ext4 */
529 #define EXT4_GET_BLOCKS_CREATE			0x0001
530 	/* Request the creation of an unwritten extent */
531 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
532 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
533 						 EXT4_GET_BLOCKS_CREATE)
534 	/* Caller is from the delayed allocation writeout path
535 	 * finally doing the actual allocation of delayed blocks */
536 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
537 	/* caller is from the direct IO path, request to creation of an
538 	unwritten extents if not allocated, split the unwritten
539 	extent if blocks has been preallocated already*/
540 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
541 #define EXT4_GET_BLOCKS_CONVERT			0x0010
542 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
543 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
544 	/* Convert extent to initialized after IO complete */
545 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
546 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
547 	/* Eventual metadata allocation (due to growing extent tree)
548 	 * should not fail, so try to use reserved blocks for that.*/
549 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
550 	/* Don't normalize allocation size (used for fallocate) */
551 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
552 	/* Request will not result in inode size update (user for fallocate) */
553 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
554 	/* Do not take i_data_sem locking in ext4_map_blocks */
555 #define EXT4_GET_BLOCKS_NO_LOCK			0x0100
556 	/* Convert written extents to unwritten */
557 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0200
558 
559 /*
560  * The bit position of these flags must not overlap with any of the
561  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
562  * read_extent_tree_block(), ext4_split_extent_at(),
563  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
564  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
565  * caching the extents when reading from the extent tree while a
566  * truncate or punch hole operation is in progress.
567  */
568 #define EXT4_EX_NOCACHE				0x40000000
569 #define EXT4_EX_FORCE_CACHE			0x20000000
570 
571 /*
572  * Flags used by ext4_free_blocks
573  */
574 #define EXT4_FREE_BLOCKS_METADATA	0x0001
575 #define EXT4_FREE_BLOCKS_FORGET		0x0002
576 #define EXT4_FREE_BLOCKS_VALIDATED	0x0004
577 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE	0x0008
578 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
579 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
580 
581 /* Encryption algorithms */
582 #define EXT4_ENCRYPTION_MODE_INVALID		0
583 #define EXT4_ENCRYPTION_MODE_AES_256_XTS	1
584 #define EXT4_ENCRYPTION_MODE_AES_256_GCM	2
585 #define EXT4_ENCRYPTION_MODE_AES_256_CBC	3
586 #define EXT4_ENCRYPTION_MODE_AES_256_CTS	4
587 
588 #include "ext4_crypto.h"
589 
590 /*
591  * ioctl commands
592  */
593 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
594 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
595 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
596 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
597 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
598 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
599 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
600 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
601 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
602 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
603 #define EXT4_IOC_MIGRATE		_IO('f', 9)
604  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
605  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
606 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
607 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
608 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
609 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
610 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
611 #define EXT4_IOC_SET_ENCRYPTION_POLICY	_IOR('f', 19, struct ext4_encryption_policy)
612 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	_IOW('f', 20, __u8[16])
613 #define EXT4_IOC_GET_ENCRYPTION_POLICY	_IOW('f', 21, struct ext4_encryption_policy)
614 
615 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
616 /*
617  * ioctl commands in 32 bit emulation
618  */
619 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
620 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
621 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
622 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
623 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
624 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
625 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
626 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
627 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
628 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
629 #endif
630 
631 /* Max physical block we can address w/o extents */
632 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
633 
634 /*
635  * Structure of an inode on the disk
636  */
637 struct ext4_inode {
638 	__le16	i_mode;		/* File mode */
639 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
640 	__le32	i_size_lo;	/* Size in bytes */
641 	__le32	i_atime;	/* Access time */
642 	__le32	i_ctime;	/* Inode Change time */
643 	__le32	i_mtime;	/* Modification time */
644 	__le32	i_dtime;	/* Deletion Time */
645 	__le16	i_gid;		/* Low 16 bits of Group Id */
646 	__le16	i_links_count;	/* Links count */
647 	__le32	i_blocks_lo;	/* Blocks count */
648 	__le32	i_flags;	/* File flags */
649 	union {
650 		struct {
651 			__le32  l_i_version;
652 		} linux1;
653 		struct {
654 			__u32  h_i_translator;
655 		} hurd1;
656 		struct {
657 			__u32  m_i_reserved1;
658 		} masix1;
659 	} osd1;				/* OS dependent 1 */
660 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
661 	__le32	i_generation;	/* File version (for NFS) */
662 	__le32	i_file_acl_lo;	/* File ACL */
663 	__le32	i_size_high;
664 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
665 	union {
666 		struct {
667 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
668 			__le16	l_i_file_acl_high;
669 			__le16	l_i_uid_high;	/* these 2 fields */
670 			__le16	l_i_gid_high;	/* were reserved2[0] */
671 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
672 			__le16	l_i_reserved;
673 		} linux2;
674 		struct {
675 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
676 			__u16	h_i_mode_high;
677 			__u16	h_i_uid_high;
678 			__u16	h_i_gid_high;
679 			__u32	h_i_author;
680 		} hurd2;
681 		struct {
682 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
683 			__le16	m_i_file_acl_high;
684 			__u32	m_i_reserved2[2];
685 		} masix2;
686 	} osd2;				/* OS dependent 2 */
687 	__le16	i_extra_isize;
688 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
689 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
690 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
691 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
692 	__le32  i_crtime;       /* File Creation time */
693 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
694 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
695 };
696 
697 struct move_extent {
698 	__u32 reserved;		/* should be zero */
699 	__u32 donor_fd;		/* donor file descriptor */
700 	__u64 orig_start;	/* logical start offset in block for orig */
701 	__u64 donor_start;	/* logical start offset in block for donor */
702 	__u64 len;		/* block length to be moved */
703 	__u64 moved_len;	/* moved block length */
704 };
705 
706 #define EXT4_EPOCH_BITS 2
707 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
708 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
709 
710 /*
711  * Extended fields will fit into an inode if the filesystem was formatted
712  * with large inodes (-I 256 or larger) and there are not currently any EAs
713  * consuming all of the available space. For new inodes we always reserve
714  * enough space for the kernel's known extended fields, but for inodes
715  * created with an old kernel this might not have been the case. None of
716  * the extended inode fields is critical for correct filesystem operation.
717  * This macro checks if a certain field fits in the inode. Note that
718  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
719  */
720 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
721 	((offsetof(typeof(*ext4_inode), field) +	\
722 	  sizeof((ext4_inode)->field))			\
723 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
724 	    (einode)->i_extra_isize))			\
725 
726 static inline __le32 ext4_encode_extra_time(struct timespec *time)
727 {
728        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
729 			   (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
730                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
731 }
732 
733 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
734 {
735        if (sizeof(time->tv_sec) > 4)
736 	       time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
737 			       << 32;
738        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
739 }
740 
741 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)			       \
742 do {									       \
743 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	       \
744 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
745 		(raw_inode)->xtime ## _extra =				       \
746 				ext4_encode_extra_time(&(inode)->xtime);       \
747 } while (0)
748 
749 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
750 do {									       \
751 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
752 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
753 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
754 		(raw_inode)->xtime ## _extra =				       \
755 				ext4_encode_extra_time(&(einode)->xtime);      \
756 } while (0)
757 
758 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)			       \
759 do {									       \
760 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
761 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
762 		ext4_decode_extra_time(&(inode)->xtime,			       \
763 				       raw_inode->xtime ## _extra);	       \
764 	else								       \
765 		(inode)->xtime.tv_nsec = 0;				       \
766 } while (0)
767 
768 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
769 do {									       \
770 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
771 		(einode)->xtime.tv_sec = 				       \
772 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
773 	else								       \
774 		(einode)->xtime.tv_sec = 0;				       \
775 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
776 		ext4_decode_extra_time(&(einode)->xtime,		       \
777 				       raw_inode->xtime ## _extra);	       \
778 	else								       \
779 		(einode)->xtime.tv_nsec = 0;				       \
780 } while (0)
781 
782 #define i_disk_version osd1.linux1.l_i_version
783 
784 #if defined(__KERNEL__) || defined(__linux__)
785 #define i_reserved1	osd1.linux1.l_i_reserved1
786 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
787 #define i_blocks_high	osd2.linux2.l_i_blocks_high
788 #define i_uid_low	i_uid
789 #define i_gid_low	i_gid
790 #define i_uid_high	osd2.linux2.l_i_uid_high
791 #define i_gid_high	osd2.linux2.l_i_gid_high
792 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
793 
794 #elif defined(__GNU__)
795 
796 #define i_translator	osd1.hurd1.h_i_translator
797 #define i_uid_high	osd2.hurd2.h_i_uid_high
798 #define i_gid_high	osd2.hurd2.h_i_gid_high
799 #define i_author	osd2.hurd2.h_i_author
800 
801 #elif defined(__masix__)
802 
803 #define i_reserved1	osd1.masix1.m_i_reserved1
804 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
805 #define i_reserved2	osd2.masix2.m_i_reserved2
806 
807 #endif /* defined(__KERNEL__) || defined(__linux__) */
808 
809 #include "extents_status.h"
810 
811 /*
812  * fourth extended file system inode data in memory
813  */
814 struct ext4_inode_info {
815 	__le32	i_data[15];	/* unconverted */
816 	__u32	i_dtime;
817 	ext4_fsblk_t	i_file_acl;
818 
819 	/*
820 	 * i_block_group is the number of the block group which contains
821 	 * this file's inode.  Constant across the lifetime of the inode,
822 	 * it is ued for making block allocation decisions - we try to
823 	 * place a file's data blocks near its inode block, and new inodes
824 	 * near to their parent directory's inode.
825 	 */
826 	ext4_group_t	i_block_group;
827 	ext4_lblk_t	i_dir_start_lookup;
828 #if (BITS_PER_LONG < 64)
829 	unsigned long	i_state_flags;		/* Dynamic state flags */
830 #endif
831 	unsigned long	i_flags;
832 
833 	/*
834 	 * Extended attributes can be read independently of the main file
835 	 * data. Taking i_mutex even when reading would cause contention
836 	 * between readers of EAs and writers of regular file data, so
837 	 * instead we synchronize on xattr_sem when reading or changing
838 	 * EAs.
839 	 */
840 	struct rw_semaphore xattr_sem;
841 
842 	struct list_head i_orphan;	/* unlinked but open inodes */
843 
844 	/*
845 	 * i_disksize keeps track of what the inode size is ON DISK, not
846 	 * in memory.  During truncate, i_size is set to the new size by
847 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
848 	 * set i_disksize to 0 until the truncate is actually under way.
849 	 *
850 	 * The intent is that i_disksize always represents the blocks which
851 	 * are used by this file.  This allows recovery to restart truncate
852 	 * on orphans if we crash during truncate.  We actually write i_disksize
853 	 * into the on-disk inode when writing inodes out, instead of i_size.
854 	 *
855 	 * The only time when i_disksize and i_size may be different is when
856 	 * a truncate is in progress.  The only things which change i_disksize
857 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
858 	 */
859 	loff_t	i_disksize;
860 
861 	/*
862 	 * i_data_sem is for serialising ext4_truncate() against
863 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
864 	 * data tree are chopped off during truncate. We can't do that in
865 	 * ext4 because whenever we perform intermediate commits during
866 	 * truncate, the inode and all the metadata blocks *must* be in a
867 	 * consistent state which allows truncation of the orphans to restart
868 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
869 	 * by other means, so we have i_data_sem.
870 	 */
871 	struct rw_semaphore i_data_sem;
872 	struct inode vfs_inode;
873 	struct jbd2_inode *jinode;
874 
875 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
876 
877 	/*
878 	 * File creation time. Its function is same as that of
879 	 * struct timespec i_{a,c,m}time in the generic inode.
880 	 */
881 	struct timespec i_crtime;
882 
883 	/* mballoc */
884 	struct list_head i_prealloc_list;
885 	spinlock_t i_prealloc_lock;
886 
887 	/* extents status tree */
888 	struct ext4_es_tree i_es_tree;
889 	rwlock_t i_es_lock;
890 	struct list_head i_es_list;
891 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
892 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
893 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
894 					   extents to shrink. Protected by
895 					   i_es_lock  */
896 
897 	/* ialloc */
898 	ext4_group_t	i_last_alloc_group;
899 
900 	/* allocation reservation info for delalloc */
901 	/* In case of bigalloc, these refer to clusters rather than blocks */
902 	unsigned int i_reserved_data_blocks;
903 	unsigned int i_reserved_meta_blocks;
904 	unsigned int i_allocated_meta_blocks;
905 	ext4_lblk_t i_da_metadata_calc_last_lblock;
906 	int i_da_metadata_calc_len;
907 
908 	/* on-disk additional length */
909 	__u16 i_extra_isize;
910 
911 	/* Indicate the inline data space. */
912 	u16 i_inline_off;
913 	u16 i_inline_size;
914 
915 #ifdef CONFIG_QUOTA
916 	/* quota space reservation, managed internally by quota code */
917 	qsize_t i_reserved_quota;
918 #endif
919 
920 	/* Lock protecting lists below */
921 	spinlock_t i_completed_io_lock;
922 	/*
923 	 * Completed IOs that need unwritten extents handling and have
924 	 * transaction reserved
925 	 */
926 	struct list_head i_rsv_conversion_list;
927 	/*
928 	 * Completed IOs that need unwritten extents handling and don't have
929 	 * transaction reserved
930 	 */
931 	atomic_t i_ioend_count;	/* Number of outstanding io_end structs */
932 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
933 	struct work_struct i_rsv_conversion_work;
934 
935 	spinlock_t i_block_reservation_lock;
936 
937 	/*
938 	 * Transactions that contain inode's metadata needed to complete
939 	 * fsync and fdatasync, respectively.
940 	 */
941 	tid_t i_sync_tid;
942 	tid_t i_datasync_tid;
943 
944 #ifdef CONFIG_QUOTA
945 	struct dquot *i_dquot[MAXQUOTAS];
946 #endif
947 
948 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
949 	__u32 i_csum_seed;
950 
951 #ifdef CONFIG_EXT4_FS_ENCRYPTION
952 	/* Encryption params */
953 	struct ext4_crypt_info *i_crypt_info;
954 #endif
955 };
956 
957 /*
958  * File system states
959  */
960 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
961 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
962 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
963 
964 /*
965  * Misc. filesystem flags
966  */
967 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
968 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
969 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
970 
971 /*
972  * Mount flags set via mount options or defaults
973  */
974 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
975 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
976 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
977 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
978 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
979 #define EXT4_MOUNT_ERRORS_MASK		0x00070
980 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
981 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
982 #ifdef CONFIG_FS_DAX
983 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
984 #else
985 #define EXT4_MOUNT_DAX			0
986 #endif
987 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
988 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
989 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
990 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
991 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
992 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
993 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
994 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
995 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
996 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
997 #define EXT4_MOUNT_QUOTA		0x80000 /* Some quota option set */
998 #define EXT4_MOUNT_USRQUOTA		0x100000 /* "old" user quota */
999 #define EXT4_MOUNT_GRPQUOTA		0x200000 /* "old" group quota */
1000 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1001 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1002 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1003 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1004 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1005 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1006 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1007 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1008 
1009 /*
1010  * Mount flags set either automatically (could not be set by mount option)
1011  * based on per file system feature or property or in special cases such as
1012  * distinguishing between explicit mount option definition and default.
1013  */
1014 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1015 						      specified delalloc */
1016 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1017 						      size of blocksize * 8
1018 						      blocks */
1019 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1020 						      file systems */
1021 
1022 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1023 						~EXT4_MOUNT_##opt
1024 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1025 						EXT4_MOUNT_##opt
1026 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1027 					 EXT4_MOUNT_##opt)
1028 
1029 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1030 						~EXT4_MOUNT2_##opt
1031 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1032 						EXT4_MOUNT2_##opt
1033 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1034 					 EXT4_MOUNT2_##opt)
1035 
1036 #define ext4_test_and_set_bit		__test_and_set_bit_le
1037 #define ext4_set_bit			__set_bit_le
1038 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1039 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1040 #define ext4_clear_bit			__clear_bit_le
1041 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1042 #define ext4_test_bit			test_bit_le
1043 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1044 #define ext4_find_next_bit		find_next_bit_le
1045 
1046 extern void ext4_set_bits(void *bm, int cur, int len);
1047 
1048 /*
1049  * Maximal mount counts between two filesystem checks
1050  */
1051 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1052 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1053 
1054 /*
1055  * Behaviour when detecting errors
1056  */
1057 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1058 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1059 #define EXT4_ERRORS_PANIC		3	/* Panic */
1060 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1061 
1062 /* Metadata checksum algorithm codes */
1063 #define EXT4_CRC32C_CHKSUM		1
1064 
1065 /*
1066  * Structure of the super block
1067  */
1068 struct ext4_super_block {
1069 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1070 	__le32	s_blocks_count_lo;	/* Blocks count */
1071 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1072 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1073 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1074 	__le32	s_first_data_block;	/* First Data Block */
1075 	__le32	s_log_block_size;	/* Block size */
1076 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1077 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1078 	__le32	s_clusters_per_group;	/* # Clusters per group */
1079 	__le32	s_inodes_per_group;	/* # Inodes per group */
1080 	__le32	s_mtime;		/* Mount time */
1081 /*30*/	__le32	s_wtime;		/* Write time */
1082 	__le16	s_mnt_count;		/* Mount count */
1083 	__le16	s_max_mnt_count;	/* Maximal mount count */
1084 	__le16	s_magic;		/* Magic signature */
1085 	__le16	s_state;		/* File system state */
1086 	__le16	s_errors;		/* Behaviour when detecting errors */
1087 	__le16	s_minor_rev_level;	/* minor revision level */
1088 /*40*/	__le32	s_lastcheck;		/* time of last check */
1089 	__le32	s_checkinterval;	/* max. time between checks */
1090 	__le32	s_creator_os;		/* OS */
1091 	__le32	s_rev_level;		/* Revision level */
1092 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1093 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1094 	/*
1095 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1096 	 *
1097 	 * Note: the difference between the compatible feature set and
1098 	 * the incompatible feature set is that if there is a bit set
1099 	 * in the incompatible feature set that the kernel doesn't
1100 	 * know about, it should refuse to mount the filesystem.
1101 	 *
1102 	 * e2fsck's requirements are more strict; if it doesn't know
1103 	 * about a feature in either the compatible or incompatible
1104 	 * feature set, it must abort and not try to meddle with
1105 	 * things it doesn't understand...
1106 	 */
1107 	__le32	s_first_ino;		/* First non-reserved inode */
1108 	__le16  s_inode_size;		/* size of inode structure */
1109 	__le16	s_block_group_nr;	/* block group # of this superblock */
1110 	__le32	s_feature_compat;	/* compatible feature set */
1111 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1112 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1113 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1114 /*78*/	char	s_volume_name[16];	/* volume name */
1115 /*88*/	char	s_last_mounted[64];	/* directory where last mounted */
1116 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1117 	/*
1118 	 * Performance hints.  Directory preallocation should only
1119 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1120 	 */
1121 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1122 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1123 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1124 	/*
1125 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1126 	 */
1127 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1128 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1129 	__le32	s_journal_dev;		/* device number of journal file */
1130 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1131 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1132 	__u8	s_def_hash_version;	/* Default hash version to use */
1133 	__u8	s_jnl_backup_type;
1134 	__le16  s_desc_size;		/* size of group descriptor */
1135 /*100*/	__le32	s_default_mount_opts;
1136 	__le32	s_first_meta_bg;	/* First metablock block group */
1137 	__le32	s_mkfs_time;		/* When the filesystem was created */
1138 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1139 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1140 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1141 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1142 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1143 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1144 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1145 	__le32	s_flags;		/* Miscellaneous flags */
1146 	__le16  s_raid_stride;		/* RAID stride */
1147 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1148 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1149 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1150 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1151 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1152 	__u8	s_encryption_level;	/* versioning level for encryption */
1153 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1154 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1155 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1156 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1157 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1158 					      snapshot's future use */
1159 	__le32	s_snapshot_list;	/* inode number of the head of the
1160 					   on-disk snapshot list */
1161 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1162 	__le32	s_error_count;		/* number of fs errors */
1163 	__le32	s_first_error_time;	/* first time an error happened */
1164 	__le32	s_first_error_ino;	/* inode involved in first error */
1165 	__le64	s_first_error_block;	/* block involved of first error */
1166 	__u8	s_first_error_func[32];	/* function where the error happened */
1167 	__le32	s_first_error_line;	/* line number where error happened */
1168 	__le32	s_last_error_time;	/* most recent time of an error */
1169 	__le32	s_last_error_ino;	/* inode involved in last error */
1170 	__le32	s_last_error_line;	/* line number where error happened */
1171 	__le64	s_last_error_block;	/* block involved of last error */
1172 	__u8	s_last_error_func[32];	/* function where the error happened */
1173 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1174 	__u8	s_mount_opts[64];
1175 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1176 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1177 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1178 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1179 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1180 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1181 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1182 	__le32	s_reserved[100];	/* Padding to the end of the block */
1183 	__le32	s_checksum;		/* crc32c(superblock) */
1184 };
1185 
1186 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1187 
1188 #ifdef __KERNEL__
1189 
1190 /*
1191  * run-time mount flags
1192  */
1193 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1194 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1195 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1196 
1197 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1198 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1199 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1200 #else
1201 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1202 #endif
1203 
1204 /* Number of quota types we support */
1205 #define EXT4_MAXQUOTAS 2
1206 
1207 /*
1208  * fourth extended-fs super-block data in memory
1209  */
1210 struct ext4_sb_info {
1211 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1212 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1213 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1214 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1215 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1216 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1217 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1218 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1219 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1220 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1221 	unsigned long s_overhead;  /* # of fs overhead clusters */
1222 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1223 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1224 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1225 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1226 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1227 	struct buffer_head **s_group_desc;
1228 	unsigned int s_mount_opt;
1229 	unsigned int s_mount_opt2;
1230 	unsigned int s_mount_flags;
1231 	unsigned int s_def_mount_opt;
1232 	ext4_fsblk_t s_sb_block;
1233 	atomic64_t s_resv_clusters;
1234 	kuid_t s_resuid;
1235 	kgid_t s_resgid;
1236 	unsigned short s_mount_state;
1237 	unsigned short s_pad;
1238 	int s_addr_per_block_bits;
1239 	int s_desc_per_block_bits;
1240 	int s_inode_size;
1241 	int s_first_ino;
1242 	unsigned int s_inode_readahead_blks;
1243 	unsigned int s_inode_goal;
1244 	spinlock_t s_next_gen_lock;
1245 	u32 s_next_generation;
1246 	u32 s_hash_seed[4];
1247 	int s_def_hash_version;
1248 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1249 	struct percpu_counter s_freeclusters_counter;
1250 	struct percpu_counter s_freeinodes_counter;
1251 	struct percpu_counter s_dirs_counter;
1252 	struct percpu_counter s_dirtyclusters_counter;
1253 	struct blockgroup_lock *s_blockgroup_lock;
1254 	struct proc_dir_entry *s_proc;
1255 	struct kobject s_kobj;
1256 	struct completion s_kobj_unregister;
1257 	struct super_block *s_sb;
1258 
1259 	/* Journaling */
1260 	struct journal_s *s_journal;
1261 	struct list_head s_orphan;
1262 	struct mutex s_orphan_lock;
1263 	unsigned long s_resize_flags;		/* Flags indicating if there
1264 						   is a resizer */
1265 	unsigned long s_commit_interval;
1266 	u32 s_max_batch_time;
1267 	u32 s_min_batch_time;
1268 	struct block_device *journal_bdev;
1269 #ifdef CONFIG_QUOTA
1270 	char *s_qf_names[EXT4_MAXQUOTAS];	/* Names of quota files with journalled quota */
1271 	int s_jquota_fmt;			/* Format of quota to use */
1272 #endif
1273 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1274 	struct rb_root system_blks;
1275 
1276 #ifdef EXTENTS_STATS
1277 	/* ext4 extents stats */
1278 	unsigned long s_ext_min;
1279 	unsigned long s_ext_max;
1280 	unsigned long s_depth_max;
1281 	spinlock_t s_ext_stats_lock;
1282 	unsigned long s_ext_blocks;
1283 	unsigned long s_ext_extents;
1284 #endif
1285 
1286 	/* for buddy allocator */
1287 	struct ext4_group_info ***s_group_info;
1288 	struct inode *s_buddy_cache;
1289 	spinlock_t s_md_lock;
1290 	unsigned short *s_mb_offsets;
1291 	unsigned int *s_mb_maxs;
1292 	unsigned int s_group_info_size;
1293 
1294 	/* tunables */
1295 	unsigned long s_stripe;
1296 	unsigned int s_mb_stream_request;
1297 	unsigned int s_mb_max_to_scan;
1298 	unsigned int s_mb_min_to_scan;
1299 	unsigned int s_mb_stats;
1300 	unsigned int s_mb_order2_reqs;
1301 	unsigned int s_mb_group_prealloc;
1302 	unsigned int s_max_dir_size_kb;
1303 	/* where last allocation was done - for stream allocation */
1304 	unsigned long s_mb_last_group;
1305 	unsigned long s_mb_last_start;
1306 
1307 	/* stats for buddy allocator */
1308 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1309 	atomic_t s_bal_success;	/* we found long enough chunks */
1310 	atomic_t s_bal_allocated;	/* in blocks */
1311 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1312 	atomic_t s_bal_goals;	/* goal hits */
1313 	atomic_t s_bal_breaks;	/* too long searches */
1314 	atomic_t s_bal_2orders;	/* 2^order hits */
1315 	spinlock_t s_bal_lock;
1316 	unsigned long s_mb_buddies_generated;
1317 	unsigned long long s_mb_generation_time;
1318 	atomic_t s_mb_lost_chunks;
1319 	atomic_t s_mb_preallocated;
1320 	atomic_t s_mb_discarded;
1321 	atomic_t s_lock_busy;
1322 
1323 	/* locality groups */
1324 	struct ext4_locality_group __percpu *s_locality_groups;
1325 
1326 	/* for write statistics */
1327 	unsigned long s_sectors_written_start;
1328 	u64 s_kbytes_written;
1329 
1330 	/* the size of zero-out chunk */
1331 	unsigned int s_extent_max_zeroout_kb;
1332 
1333 	unsigned int s_log_groups_per_flex;
1334 	struct flex_groups *s_flex_groups;
1335 	ext4_group_t s_flex_groups_allocated;
1336 
1337 	/* workqueue for reserved extent conversions (buffered io) */
1338 	struct workqueue_struct *rsv_conversion_wq;
1339 
1340 	/* timer for periodic error stats printing */
1341 	struct timer_list s_err_report;
1342 
1343 	/* Lazy inode table initialization info */
1344 	struct ext4_li_request *s_li_request;
1345 	/* Wait multiplier for lazy initialization thread */
1346 	unsigned int s_li_wait_mult;
1347 
1348 	/* Kernel thread for multiple mount protection */
1349 	struct task_struct *s_mmp_tsk;
1350 
1351 	/* record the last minlen when FITRIM is called. */
1352 	atomic_t s_last_trim_minblks;
1353 
1354 	/* Reference to checksum algorithm driver via cryptoapi */
1355 	struct crypto_shash *s_chksum_driver;
1356 
1357 	/* Precomputed FS UUID checksum for seeding other checksums */
1358 	__u32 s_csum_seed;
1359 
1360 	/* Reclaim extents from extent status tree */
1361 	struct shrinker s_es_shrinker;
1362 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1363 	long s_es_nr_inode;
1364 	struct ext4_es_stats s_es_stats;
1365 	struct mb_cache *s_mb_cache;
1366 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1367 
1368 	/* Ratelimit ext4 messages. */
1369 	struct ratelimit_state s_err_ratelimit_state;
1370 	struct ratelimit_state s_warning_ratelimit_state;
1371 	struct ratelimit_state s_msg_ratelimit_state;
1372 };
1373 
1374 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1375 {
1376 	return sb->s_fs_info;
1377 }
1378 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1379 {
1380 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1381 }
1382 
1383 static inline struct timespec ext4_current_time(struct inode *inode)
1384 {
1385 	return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1386 		current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1387 }
1388 
1389 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1390 {
1391 	return ino == EXT4_ROOT_INO ||
1392 		ino == EXT4_USR_QUOTA_INO ||
1393 		ino == EXT4_GRP_QUOTA_INO ||
1394 		ino == EXT4_BOOT_LOADER_INO ||
1395 		ino == EXT4_JOURNAL_INO ||
1396 		ino == EXT4_RESIZE_INO ||
1397 		(ino >= EXT4_FIRST_INO(sb) &&
1398 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1399 }
1400 
1401 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1402 					      struct ext4_io_end *io_end)
1403 {
1404 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1405 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
1406 		atomic_inc(&EXT4_I(inode)->i_unwritten);
1407 	}
1408 }
1409 
1410 static inline ext4_io_end_t *ext4_inode_aio(struct inode *inode)
1411 {
1412 	return inode->i_private;
1413 }
1414 
1415 static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
1416 {
1417 	inode->i_private = io;
1418 }
1419 
1420 /*
1421  * Inode dynamic state flags
1422  */
1423 enum {
1424 	EXT4_STATE_JDATA,		/* journaled data exists */
1425 	EXT4_STATE_NEW,			/* inode is newly created */
1426 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1427 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1428 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1429 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1430 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1431 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1432 	EXT4_STATE_DIOREAD_LOCK,	/* Disable support for dio read
1433 					   nolocking */
1434 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1435 	EXT4_STATE_ORDERED_MODE,	/* data=ordered mode */
1436 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1437 };
1438 
1439 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1440 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1441 {									\
1442 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1443 }									\
1444 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1445 {									\
1446 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1447 }									\
1448 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1449 {									\
1450 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1451 }
1452 
1453 /* Add these declarations here only so that these functions can be
1454  * found by name.  Otherwise, they are very hard to locate. */
1455 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1456 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1457 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1458 EXT4_INODE_BIT_FNS(flag, flags, 0)
1459 
1460 /* Add these declarations here only so that these functions can be
1461  * found by name.  Otherwise, they are very hard to locate. */
1462 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1463 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1464 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1465 #if (BITS_PER_LONG < 64)
1466 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1467 
1468 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1469 {
1470 	(ei)->i_state_flags = 0;
1471 }
1472 #else
1473 EXT4_INODE_BIT_FNS(state, flags, 32)
1474 
1475 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1476 {
1477 	/* We depend on the fact that callers will set i_flags */
1478 }
1479 #endif
1480 #else
1481 /* Assume that user mode programs are passing in an ext4fs superblock, not
1482  * a kernel struct super_block.  This will allow us to call the feature-test
1483  * macros from user land. */
1484 #define EXT4_SB(sb)	(sb)
1485 #endif
1486 
1487 /*
1488  * Returns true if the inode is inode is encrypted
1489  */
1490 static inline int ext4_encrypted_inode(struct inode *inode)
1491 {
1492 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1493 	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
1494 #else
1495 	return 0;
1496 #endif
1497 }
1498 
1499 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1500 
1501 /*
1502  * Codes for operating systems
1503  */
1504 #define EXT4_OS_LINUX		0
1505 #define EXT4_OS_HURD		1
1506 #define EXT4_OS_MASIX		2
1507 #define EXT4_OS_FREEBSD		3
1508 #define EXT4_OS_LITES		4
1509 
1510 /*
1511  * Revision levels
1512  */
1513 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1514 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1515 
1516 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1517 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1518 
1519 #define EXT4_GOOD_OLD_INODE_SIZE 128
1520 
1521 /*
1522  * Feature set definitions
1523  */
1524 
1525 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)			\
1526 	((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1527 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)			\
1528 	((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1529 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)			\
1530 	((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1531 #define EXT4_SET_COMPAT_FEATURE(sb,mask)			\
1532 	EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1533 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)			\
1534 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1535 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)			\
1536 	EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1537 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)			\
1538 	EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1539 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
1540 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1541 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
1542 	EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1543 
1544 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1545 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1546 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1547 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1548 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1549 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1550 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1551 
1552 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1553 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1554 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1555 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1556 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1557 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1558 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1559 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1560 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1561 /*
1562  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1563  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1564  * all other data structures' checksums.  However, the METADATA_CSUM and
1565  * GDT_CSUM bits are mutually exclusive.
1566  */
1567 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1568 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1569 
1570 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1571 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1572 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1573 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1574 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1575 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1576 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1577 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1578 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1579 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1580 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1581 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM	0x2000 /* use crc32c for bg */
1582 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1583 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1584 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1585 
1586 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1587 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1588 					 EXT4_FEATURE_INCOMPAT_META_BG)
1589 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1590 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1591 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1592 
1593 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1594 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1595 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1596 					 EXT4_FEATURE_INCOMPAT_META_BG)
1597 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1598 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1599 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1600 
1601 #define EXT4_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR
1602 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1603 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1604 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1605 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1606 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1607 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1608 					 EXT4_FEATURE_INCOMPAT_MMP | \
1609 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1610 					 EXT4_FEATURE_INCOMPAT_ENCRYPT)
1611 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1612 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1613 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1614 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1615 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1616 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1617 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1618 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1619 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1620 					 EXT4_FEATURE_RO_COMPAT_QUOTA)
1621 
1622 /*
1623  * Default values for user and/or group using reserved blocks
1624  */
1625 #define	EXT4_DEF_RESUID		0
1626 #define	EXT4_DEF_RESGID		0
1627 
1628 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1629 
1630 /*
1631  * Default mount options
1632  */
1633 #define EXT4_DEFM_DEBUG		0x0001
1634 #define EXT4_DEFM_BSDGROUPS	0x0002
1635 #define EXT4_DEFM_XATTR_USER	0x0004
1636 #define EXT4_DEFM_ACL		0x0008
1637 #define EXT4_DEFM_UID16		0x0010
1638 #define EXT4_DEFM_JMODE		0x0060
1639 #define EXT4_DEFM_JMODE_DATA	0x0020
1640 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1641 #define EXT4_DEFM_JMODE_WBACK	0x0060
1642 #define EXT4_DEFM_NOBARRIER	0x0100
1643 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1644 #define EXT4_DEFM_DISCARD	0x0400
1645 #define EXT4_DEFM_NODELALLOC	0x0800
1646 
1647 /*
1648  * Default journal batch times
1649  */
1650 #define EXT4_DEF_MIN_BATCH_TIME	0
1651 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1652 
1653 /*
1654  * Minimum number of groups in a flexgroup before we separate out
1655  * directories into the first block group of a flexgroup
1656  */
1657 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1658 
1659 /*
1660  * Structure of a directory entry
1661  */
1662 #define EXT4_NAME_LEN 255
1663 
1664 struct ext4_dir_entry {
1665 	__le32	inode;			/* Inode number */
1666 	__le16	rec_len;		/* Directory entry length */
1667 	__le16	name_len;		/* Name length */
1668 	char	name[EXT4_NAME_LEN];	/* File name */
1669 };
1670 
1671 /*
1672  * The new version of the directory entry.  Since EXT4 structures are
1673  * stored in intel byte order, and the name_len field could never be
1674  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1675  * file_type field.
1676  */
1677 struct ext4_dir_entry_2 {
1678 	__le32	inode;			/* Inode number */
1679 	__le16	rec_len;		/* Directory entry length */
1680 	__u8	name_len;		/* Name length */
1681 	__u8	file_type;
1682 	char	name[EXT4_NAME_LEN];	/* File name */
1683 };
1684 
1685 /*
1686  * This is a bogus directory entry at the end of each leaf block that
1687  * records checksums.
1688  */
1689 struct ext4_dir_entry_tail {
1690 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1691 	__le16	det_rec_len;		/* 12 */
1692 	__u8	det_reserved_zero2;	/* Zero name length */
1693 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1694 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1695 };
1696 
1697 #define EXT4_DIRENT_TAIL(block, blocksize) \
1698 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1699 					((blocksize) - \
1700 					 sizeof(struct ext4_dir_entry_tail))))
1701 
1702 /*
1703  * Ext4 directory file types.  Only the low 3 bits are used.  The
1704  * other bits are reserved for now.
1705  */
1706 #define EXT4_FT_UNKNOWN		0
1707 #define EXT4_FT_REG_FILE	1
1708 #define EXT4_FT_DIR		2
1709 #define EXT4_FT_CHRDEV		3
1710 #define EXT4_FT_BLKDEV		4
1711 #define EXT4_FT_FIFO		5
1712 #define EXT4_FT_SOCK		6
1713 #define EXT4_FT_SYMLINK		7
1714 
1715 #define EXT4_FT_MAX		8
1716 
1717 #define EXT4_FT_DIR_CSUM	0xDE
1718 
1719 /*
1720  * EXT4_DIR_PAD defines the directory entries boundaries
1721  *
1722  * NOTE: It must be a multiple of 4
1723  */
1724 #define EXT4_DIR_PAD			4
1725 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1726 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1727 					 ~EXT4_DIR_ROUND)
1728 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1729 
1730 /*
1731  * If we ever get support for fs block sizes > page_size, we'll need
1732  * to remove the #if statements in the next two functions...
1733  */
1734 static inline unsigned int
1735 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1736 {
1737 	unsigned len = le16_to_cpu(dlen);
1738 
1739 #if (PAGE_CACHE_SIZE >= 65536)
1740 	if (len == EXT4_MAX_REC_LEN || len == 0)
1741 		return blocksize;
1742 	return (len & 65532) | ((len & 3) << 16);
1743 #else
1744 	return len;
1745 #endif
1746 }
1747 
1748 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1749 {
1750 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1751 		BUG();
1752 #if (PAGE_CACHE_SIZE >= 65536)
1753 	if (len < 65536)
1754 		return cpu_to_le16(len);
1755 	if (len == blocksize) {
1756 		if (blocksize == 65536)
1757 			return cpu_to_le16(EXT4_MAX_REC_LEN);
1758 		else
1759 			return cpu_to_le16(0);
1760 	}
1761 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1762 #else
1763 	return cpu_to_le16(len);
1764 #endif
1765 }
1766 
1767 /*
1768  * Hash Tree Directory indexing
1769  * (c) Daniel Phillips, 2001
1770  */
1771 
1772 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1773 				      EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1774 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1775 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1776 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1777 
1778 /* Legal values for the dx_root hash_version field: */
1779 
1780 #define DX_HASH_LEGACY		0
1781 #define DX_HASH_HALF_MD4	1
1782 #define DX_HASH_TEA		2
1783 #define DX_HASH_LEGACY_UNSIGNED	3
1784 #define DX_HASH_HALF_MD4_UNSIGNED	4
1785 #define DX_HASH_TEA_UNSIGNED		5
1786 
1787 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1788 			      const void *address, unsigned int length)
1789 {
1790 	struct {
1791 		struct shash_desc shash;
1792 		char ctx[4];
1793 	} desc;
1794 	int err;
1795 
1796 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
1797 
1798 	desc.shash.tfm = sbi->s_chksum_driver;
1799 	desc.shash.flags = 0;
1800 	*(u32 *)desc.ctx = crc;
1801 
1802 	err = crypto_shash_update(&desc.shash, address, length);
1803 	BUG_ON(err);
1804 
1805 	return *(u32 *)desc.ctx;
1806 }
1807 
1808 #ifdef __KERNEL__
1809 
1810 /* hash info structure used by the directory hash */
1811 struct dx_hash_info
1812 {
1813 	u32		hash;
1814 	u32		minor_hash;
1815 	int		hash_version;
1816 	u32		*seed;
1817 };
1818 
1819 
1820 /* 32 and 64 bit signed EOF for dx directories */
1821 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1822 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1823 
1824 
1825 /*
1826  * Control parameters used by ext4_htree_next_block
1827  */
1828 #define HASH_NB_ALWAYS		1
1829 
1830 struct ext4_filename {
1831 	const struct qstr *usr_fname;
1832 	struct ext4_str disk_name;
1833 	struct dx_hash_info hinfo;
1834 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1835 	struct ext4_str crypto_buf;
1836 #endif
1837 };
1838 
1839 #define fname_name(p) ((p)->disk_name.name)
1840 #define fname_len(p)  ((p)->disk_name.len)
1841 
1842 /*
1843  * Describe an inode's exact location on disk and in memory
1844  */
1845 struct ext4_iloc
1846 {
1847 	struct buffer_head *bh;
1848 	unsigned long offset;
1849 	ext4_group_t block_group;
1850 };
1851 
1852 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1853 {
1854 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1855 }
1856 
1857 /*
1858  * This structure is stuffed into the struct file's private_data field
1859  * for directories.  It is where we put information so that we can do
1860  * readdir operations in hash tree order.
1861  */
1862 struct dir_private_info {
1863 	struct rb_root	root;
1864 	struct rb_node	*curr_node;
1865 	struct fname	*extra_fname;
1866 	loff_t		last_pos;
1867 	__u32		curr_hash;
1868 	__u32		curr_minor_hash;
1869 	__u32		next_hash;
1870 };
1871 
1872 /* calculate the first block number of the group */
1873 static inline ext4_fsblk_t
1874 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1875 {
1876 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1877 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1878 }
1879 
1880 /*
1881  * Special error return code only used by dx_probe() and its callers.
1882  */
1883 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
1884 
1885 /*
1886  * Timeout and state flag for lazy initialization inode thread.
1887  */
1888 #define EXT4_DEF_LI_WAIT_MULT			10
1889 #define EXT4_DEF_LI_MAX_START_DELAY		5
1890 #define EXT4_LAZYINIT_QUIT			0x0001
1891 #define EXT4_LAZYINIT_RUNNING			0x0002
1892 
1893 /*
1894  * Lazy inode table initialization info
1895  */
1896 struct ext4_lazy_init {
1897 	unsigned long		li_state;
1898 	struct list_head	li_request_list;
1899 	struct mutex		li_list_mtx;
1900 };
1901 
1902 struct ext4_li_request {
1903 	struct super_block	*lr_super;
1904 	struct ext4_sb_info	*lr_sbi;
1905 	ext4_group_t		lr_next_group;
1906 	struct list_head	lr_request;
1907 	unsigned long		lr_next_sched;
1908 	unsigned long		lr_timeout;
1909 };
1910 
1911 struct ext4_features {
1912 	struct kobject f_kobj;
1913 	struct completion f_kobj_unregister;
1914 };
1915 
1916 /*
1917  * This structure will be used for multiple mount protection. It will be
1918  * written into the block number saved in the s_mmp_block field in the
1919  * superblock. Programs that check MMP should assume that if
1920  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1921  * to use the filesystem, regardless of how old the timestamp is.
1922  */
1923 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1924 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1925 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1926 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1927 
1928 struct mmp_struct {
1929 	__le32	mmp_magic;		/* Magic number for MMP */
1930 	__le32	mmp_seq;		/* Sequence no. updated periodically */
1931 
1932 	/*
1933 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1934 	 * purposes and do not affect the correctness of the algorithm
1935 	 */
1936 	__le64	mmp_time;		/* Time last updated */
1937 	char	mmp_nodename[64];	/* Node which last updated MMP block */
1938 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
1939 
1940 	/*
1941 	 * mmp_check_interval is used to verify if the MMP block has been
1942 	 * updated on the block device. The value is updated based on the
1943 	 * maximum time to write the MMP block during an update cycle.
1944 	 */
1945 	__le16	mmp_check_interval;
1946 
1947 	__le16	mmp_pad1;
1948 	__le32	mmp_pad2[226];
1949 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
1950 };
1951 
1952 /* arguments passed to the mmp thread */
1953 struct mmpd_data {
1954 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
1955 	struct super_block *sb;  /* super block of the fs */
1956 };
1957 
1958 /*
1959  * Check interval multiplier
1960  * The MMP block is written every update interval and initially checked every
1961  * update interval x the multiplier (the value is then adapted based on the
1962  * write latency). The reason is that writes can be delayed under load and we
1963  * don't want readers to incorrectly assume that the filesystem is no longer
1964  * in use.
1965  */
1966 #define EXT4_MMP_CHECK_MULT		2UL
1967 
1968 /*
1969  * Minimum interval for MMP checking in seconds.
1970  */
1971 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
1972 
1973 /*
1974  * Maximum interval for MMP checking in seconds.
1975  */
1976 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
1977 
1978 /*
1979  * Function prototypes
1980  */
1981 
1982 /*
1983  * Ok, these declarations are also in <linux/kernel.h> but none of the
1984  * ext4 source programs needs to include it so they are duplicated here.
1985  */
1986 # define NORET_TYPE	/**/
1987 # define ATTRIB_NORET	__attribute__((noreturn))
1988 # define NORET_AND	noreturn,
1989 
1990 /* bitmap.c */
1991 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
1992 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1993 				struct ext4_group_desc *gdp,
1994 				struct buffer_head *bh, int sz);
1995 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1996 				  struct ext4_group_desc *gdp,
1997 				  struct buffer_head *bh, int sz);
1998 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1999 				struct ext4_group_desc *gdp,
2000 				struct buffer_head *bh);
2001 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2002 				  struct ext4_group_desc *gdp,
2003 				  struct buffer_head *bh);
2004 
2005 /* balloc.c */
2006 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2007 					 ext4_fsblk_t blocknr,
2008 					 ext4_group_t *blockgrpp,
2009 					 ext4_grpblk_t *offsetp);
2010 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2011 					  ext4_fsblk_t block);
2012 
2013 extern unsigned int ext4_block_group(struct super_block *sb,
2014 			ext4_fsblk_t blocknr);
2015 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2016 			ext4_fsblk_t blocknr);
2017 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2018 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2019 			ext4_group_t group);
2020 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2021 					 ext4_fsblk_t goal,
2022 					 unsigned int flags,
2023 					 unsigned long *count,
2024 					 int *errp);
2025 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2026 				    s64 nclusters, unsigned int flags);
2027 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2028 extern void ext4_check_blocks_bitmap(struct super_block *);
2029 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2030 						    ext4_group_t block_group,
2031 						    struct buffer_head ** bh);
2032 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2033 
2034 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2035 						ext4_group_t block_group);
2036 extern int ext4_wait_block_bitmap(struct super_block *sb,
2037 				  ext4_group_t block_group,
2038 				  struct buffer_head *bh);
2039 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2040 						  ext4_group_t block_group);
2041 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2042 					      ext4_group_t block_group,
2043 					      struct ext4_group_desc *gdp);
2044 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2045 
2046 /* crypto_policy.c */
2047 int ext4_is_child_context_consistent_with_parent(struct inode *parent,
2048 						 struct inode *child);
2049 int ext4_inherit_context(struct inode *parent, struct inode *child);
2050 void ext4_to_hex(char *dst, char *src, size_t src_size);
2051 int ext4_process_policy(const struct ext4_encryption_policy *policy,
2052 			struct inode *inode);
2053 int ext4_get_policy(struct inode *inode,
2054 		    struct ext4_encryption_policy *policy);
2055 
2056 /* crypto.c */
2057 extern struct kmem_cache *ext4_crypt_info_cachep;
2058 bool ext4_valid_contents_enc_mode(uint32_t mode);
2059 uint32_t ext4_validate_encryption_key_size(uint32_t mode, uint32_t size);
2060 extern struct workqueue_struct *ext4_read_workqueue;
2061 struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode);
2062 void ext4_release_crypto_ctx(struct ext4_crypto_ctx *ctx);
2063 void ext4_restore_control_page(struct page *data_page);
2064 struct page *ext4_encrypt(struct inode *inode,
2065 			  struct page *plaintext_page);
2066 int ext4_decrypt(struct ext4_crypto_ctx *ctx, struct page *page);
2067 int ext4_decrypt_one(struct inode *inode, struct page *page);
2068 int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex);
2069 
2070 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2071 int ext4_init_crypto(void);
2072 void ext4_exit_crypto(void);
2073 static inline int ext4_sb_has_crypto(struct super_block *sb)
2074 {
2075 	return EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT);
2076 }
2077 #else
2078 static inline int ext4_init_crypto(void) { return 0; }
2079 static inline void ext4_exit_crypto(void) { }
2080 static inline int ext4_sb_has_crypto(struct super_block *sb)
2081 {
2082 	return 0;
2083 }
2084 #endif
2085 
2086 /* crypto_fname.c */
2087 bool ext4_valid_filenames_enc_mode(uint32_t mode);
2088 u32 ext4_fname_crypto_round_up(u32 size, u32 blksize);
2089 unsigned ext4_fname_encrypted_size(struct inode *inode, u32 ilen);
2090 int ext4_fname_crypto_alloc_buffer(struct inode *inode,
2091 				   u32 ilen, struct ext4_str *crypto_str);
2092 int _ext4_fname_disk_to_usr(struct inode *inode,
2093 			    struct dx_hash_info *hinfo,
2094 			    const struct ext4_str *iname,
2095 			    struct ext4_str *oname);
2096 int ext4_fname_disk_to_usr(struct inode *inode,
2097 			   struct dx_hash_info *hinfo,
2098 			   const struct ext4_dir_entry_2 *de,
2099 			   struct ext4_str *oname);
2100 int ext4_fname_usr_to_disk(struct inode *inode,
2101 			   const struct qstr *iname,
2102 			   struct ext4_str *oname);
2103 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2104 void ext4_fname_crypto_free_buffer(struct ext4_str *crypto_str);
2105 int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
2106 			      int lookup, struct ext4_filename *fname);
2107 void ext4_fname_free_filename(struct ext4_filename *fname);
2108 #else
2109 static inline
2110 int ext4_setup_fname_crypto(struct inode *inode)
2111 {
2112 	return 0;
2113 }
2114 static inline void ext4_fname_crypto_free_buffer(struct ext4_str *p) { }
2115 static inline int ext4_fname_setup_filename(struct inode *dir,
2116 				     const struct qstr *iname,
2117 				     int lookup, struct ext4_filename *fname)
2118 {
2119 	fname->usr_fname = iname;
2120 	fname->disk_name.name = (unsigned char *) iname->name;
2121 	fname->disk_name.len = iname->len;
2122 	return 0;
2123 }
2124 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2125 #endif
2126 
2127 
2128 /* crypto_key.c */
2129 void ext4_free_crypt_info(struct ext4_crypt_info *ci);
2130 void ext4_free_encryption_info(struct inode *inode, struct ext4_crypt_info *ci);
2131 int _ext4_get_encryption_info(struct inode *inode);
2132 
2133 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2134 int ext4_has_encryption_key(struct inode *inode);
2135 
2136 static inline int ext4_get_encryption_info(struct inode *inode)
2137 {
2138 	struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
2139 
2140 	if (!ci ||
2141 	    (ci->ci_keyring_key &&
2142 	     (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
2143 					   (1 << KEY_FLAG_REVOKED) |
2144 					   (1 << KEY_FLAG_DEAD)))))
2145 		return _ext4_get_encryption_info(inode);
2146 	return 0;
2147 }
2148 
2149 static inline struct ext4_crypt_info *ext4_encryption_info(struct inode *inode)
2150 {
2151 	return EXT4_I(inode)->i_crypt_info;
2152 }
2153 
2154 #else
2155 static inline int ext4_has_encryption_key(struct inode *inode)
2156 {
2157 	return 0;
2158 }
2159 static inline int ext4_get_encryption_info(struct inode *inode)
2160 {
2161 	return 0;
2162 }
2163 static inline struct ext4_crypt_info *ext4_encryption_info(struct inode *inode)
2164 {
2165 	return NULL;
2166 }
2167 #endif
2168 
2169 
2170 /* dir.c */
2171 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2172 				  struct file *,
2173 				  struct ext4_dir_entry_2 *,
2174 				  struct buffer_head *, char *, int,
2175 				  unsigned int);
2176 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2177 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2178 					(de), (bh), (buf), (size), (offset)))
2179 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2180 				__u32 minor_hash,
2181 				struct ext4_dir_entry_2 *dirent,
2182 				struct ext4_str *ent_name);
2183 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2184 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2185 			     struct buffer_head *bh,
2186 			     void *buf, int buf_size,
2187 			     struct ext4_filename *fname,
2188 			     struct ext4_dir_entry_2 **dest_de);
2189 int ext4_insert_dentry(struct inode *dir,
2190 		       struct inode *inode,
2191 		       struct ext4_dir_entry_2 *de,
2192 		       int buf_size,
2193 		       struct ext4_filename *fname);
2194 static inline void ext4_update_dx_flag(struct inode *inode)
2195 {
2196 	if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
2197 				     EXT4_FEATURE_COMPAT_DIR_INDEX))
2198 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2199 }
2200 static unsigned char ext4_filetype_table[] = {
2201 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2202 };
2203 
2204 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2205 {
2206 	if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) ||
2207 	    (filetype >= EXT4_FT_MAX))
2208 		return DT_UNKNOWN;
2209 
2210 	return ext4_filetype_table[filetype];
2211 }
2212 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2213 			     void *buf, int buf_size);
2214 
2215 /* fsync.c */
2216 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2217 
2218 /* hash.c */
2219 extern int ext4fs_dirhash(const char *name, int len, struct
2220 			  dx_hash_info *hinfo);
2221 
2222 /* ialloc.c */
2223 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2224 				      const struct qstr *qstr, __u32 goal,
2225 				      uid_t *owner, int handle_type,
2226 				      unsigned int line_no, int nblocks);
2227 
2228 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner) \
2229 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2230 			 0, 0, 0)
2231 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2232 				    type, nblocks)		    \
2233 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2234 			 (type), __LINE__, (nblocks))
2235 
2236 
2237 extern void ext4_free_inode(handle_t *, struct inode *);
2238 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2239 extern unsigned long ext4_count_free_inodes(struct super_block *);
2240 extern unsigned long ext4_count_dirs(struct super_block *);
2241 extern void ext4_check_inodes_bitmap(struct super_block *);
2242 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2243 extern int ext4_init_inode_table(struct super_block *sb,
2244 				 ext4_group_t group, int barrier);
2245 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2246 
2247 /* mballoc.c */
2248 extern long ext4_mb_stats;
2249 extern long ext4_mb_max_to_scan;
2250 extern int ext4_mb_init(struct super_block *);
2251 extern int ext4_mb_release(struct super_block *);
2252 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2253 				struct ext4_allocation_request *, int *);
2254 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2255 extern void ext4_discard_preallocations(struct inode *);
2256 extern int __init ext4_init_mballoc(void);
2257 extern void ext4_exit_mballoc(void);
2258 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2259 			     struct buffer_head *bh, ext4_fsblk_t block,
2260 			     unsigned long count, int flags);
2261 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2262 				   ext4_group_t ngroups);
2263 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2264 		ext4_group_t i, struct ext4_group_desc *desc);
2265 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2266 				ext4_fsblk_t block, unsigned long count);
2267 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2268 
2269 /* inode.c */
2270 int ext4_inode_is_fast_symlink(struct inode *inode);
2271 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2272 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2273 int ext4_get_block_write(struct inode *inode, sector_t iblock,
2274 			 struct buffer_head *bh_result, int create);
2275 int ext4_get_block(struct inode *inode, sector_t iblock,
2276 				struct buffer_head *bh_result, int create);
2277 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2278 			   struct buffer_head *bh, int create);
2279 int ext4_walk_page_buffers(handle_t *handle,
2280 			   struct buffer_head *head,
2281 			   unsigned from,
2282 			   unsigned to,
2283 			   int *partial,
2284 			   int (*fn)(handle_t *handle,
2285 				     struct buffer_head *bh));
2286 int do_journal_get_write_access(handle_t *handle,
2287 				struct buffer_head *bh);
2288 #define FALL_BACK_TO_NONDELALLOC 1
2289 #define CONVERT_INLINE_DATA	 2
2290 
2291 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2292 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
2293 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2294 extern int  ext4_setattr(struct dentry *, struct iattr *);
2295 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2296 				struct kstat *stat);
2297 extern void ext4_evict_inode(struct inode *);
2298 extern void ext4_clear_inode(struct inode *);
2299 extern int  ext4_sync_inode(handle_t *, struct inode *);
2300 extern void ext4_dirty_inode(struct inode *, int);
2301 extern int ext4_change_inode_journal_flag(struct inode *, int);
2302 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2303 extern int ext4_inode_attach_jinode(struct inode *inode);
2304 extern int ext4_can_truncate(struct inode *inode);
2305 extern void ext4_truncate(struct inode *);
2306 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2307 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2308 extern void ext4_set_inode_flags(struct inode *);
2309 extern void ext4_get_inode_flags(struct ext4_inode_info *);
2310 extern int ext4_alloc_da_blocks(struct inode *inode);
2311 extern void ext4_set_aops(struct inode *inode);
2312 extern int ext4_writepage_trans_blocks(struct inode *);
2313 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2314 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2315 			     loff_t lstart, loff_t lend);
2316 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2317 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2318 extern void ext4_da_update_reserve_space(struct inode *inode,
2319 					int used, int quota_claim);
2320 
2321 /* indirect.c */
2322 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2323 				struct ext4_map_blocks *map, int flags);
2324 extern ssize_t ext4_ind_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
2325 				  loff_t offset);
2326 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2327 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2328 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2329 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2330 				 ext4_lblk_t start, ext4_lblk_t end);
2331 
2332 /* ioctl.c */
2333 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2334 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2335 
2336 /* migrate.c */
2337 extern int ext4_ext_migrate(struct inode *);
2338 extern int ext4_ind_migrate(struct inode *inode);
2339 
2340 /* namei.c */
2341 extern int ext4_dirent_csum_verify(struct inode *inode,
2342 				   struct ext4_dir_entry *dirent);
2343 extern int ext4_orphan_add(handle_t *, struct inode *);
2344 extern int ext4_orphan_del(handle_t *, struct inode *);
2345 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2346 				__u32 start_minor_hash, __u32 *next_hash);
2347 extern int ext4_search_dir(struct buffer_head *bh,
2348 			   char *search_buf,
2349 			   int buf_size,
2350 			   struct inode *dir,
2351 			   struct ext4_filename *fname,
2352 			   const struct qstr *d_name,
2353 			   unsigned int offset,
2354 			   struct ext4_dir_entry_2 **res_dir);
2355 extern int ext4_generic_delete_entry(handle_t *handle,
2356 				     struct inode *dir,
2357 				     struct ext4_dir_entry_2 *de_del,
2358 				     struct buffer_head *bh,
2359 				     void *entry_buf,
2360 				     int buf_size,
2361 				     int csum_size);
2362 extern int ext4_empty_dir(struct inode *inode);
2363 
2364 /* resize.c */
2365 extern int ext4_group_add(struct super_block *sb,
2366 				struct ext4_new_group_data *input);
2367 extern int ext4_group_extend(struct super_block *sb,
2368 				struct ext4_super_block *es,
2369 				ext4_fsblk_t n_blocks_count);
2370 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2371 
2372 /* super.c */
2373 extern int ext4_calculate_overhead(struct super_block *sb);
2374 extern void ext4_superblock_csum_set(struct super_block *sb);
2375 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2376 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2377 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2378 				    ext4_group_t ngroup);
2379 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2380 				     char nbuf[16]);
2381 
2382 extern __printf(4, 5)
2383 void __ext4_error(struct super_block *, const char *, unsigned int,
2384 		  const char *, ...);
2385 extern __printf(5, 6)
2386 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2387 		      const char *, ...);
2388 extern __printf(5, 6)
2389 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2390 		     const char *, ...);
2391 extern void __ext4_std_error(struct super_block *, const char *,
2392 			     unsigned int, int);
2393 extern __printf(4, 5)
2394 void __ext4_abort(struct super_block *, const char *, unsigned int,
2395 		  const char *, ...);
2396 extern __printf(4, 5)
2397 void __ext4_warning(struct super_block *, const char *, unsigned int,
2398 		    const char *, ...);
2399 extern __printf(4, 5)
2400 void __ext4_warning_inode(const struct inode *inode, const char *function,
2401 			  unsigned int line, const char *fmt, ...);
2402 extern __printf(3, 4)
2403 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2404 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2405 			   const char *, unsigned int, const char *);
2406 extern __printf(7, 8)
2407 void __ext4_grp_locked_error(const char *, unsigned int,
2408 			     struct super_block *, ext4_group_t,
2409 			     unsigned long, ext4_fsblk_t,
2410 			     const char *, ...);
2411 
2412 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2413 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2414 
2415 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
2416 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2417 
2418 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2419 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2420 
2421 #ifdef CONFIG_PRINTK
2422 
2423 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2424 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2425 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2426 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2427 #define ext4_error(sb, fmt, ...)					\
2428 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2429 #define ext4_abort(sb, fmt, ...)					\
2430 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2431 #define ext4_warning(sb, fmt, ...)					\
2432 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2433 #define ext4_warning_inode(inode, fmt, ...)				\
2434 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2435 #define ext4_msg(sb, level, fmt, ...)				\
2436 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2437 #define dump_mmp_msg(sb, mmp, msg)					\
2438 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2439 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2440 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2441 				fmt, ##__VA_ARGS__)
2442 
2443 #else
2444 
2445 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2446 do {									\
2447 	no_printk(fmt, ##__VA_ARGS__);					\
2448 	__ext4_error_inode(inode, "", 0, block, " ");			\
2449 } while (0)
2450 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2451 do {									\
2452 	no_printk(fmt, ##__VA_ARGS__);					\
2453 	__ext4_error_file(file, "", 0, block, " ");			\
2454 } while (0)
2455 #define ext4_error(sb, fmt, ...)					\
2456 do {									\
2457 	no_printk(fmt, ##__VA_ARGS__);					\
2458 	__ext4_error(sb, "", 0, " ");					\
2459 } while (0)
2460 #define ext4_abort(sb, fmt, ...)					\
2461 do {									\
2462 	no_printk(fmt, ##__VA_ARGS__);					\
2463 	__ext4_abort(sb, "", 0, " ");					\
2464 } while (0)
2465 #define ext4_warning(sb, fmt, ...)					\
2466 do {									\
2467 	no_printk(fmt, ##__VA_ARGS__);					\
2468 	__ext4_warning(sb, "", 0, " ");					\
2469 } while (0)
2470 #define ext4_warning_inode(inode, fmt, ...)				\
2471 do {									\
2472 	no_printk(fmt, ##__VA_ARGS__);					\
2473 	__ext4_warning_inode(inode, "", 0, " ");			\
2474 } while (0)
2475 #define ext4_msg(sb, level, fmt, ...)					\
2476 do {									\
2477 	no_printk(fmt, ##__VA_ARGS__);					\
2478 	__ext4_msg(sb, "", " ");					\
2479 } while (0)
2480 #define dump_mmp_msg(sb, mmp, msg)					\
2481 	__dump_mmp_msg(sb, mmp, "", 0, "")
2482 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2483 do {									\
2484 	no_printk(fmt, ##__VA_ARGS__);				\
2485 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2486 } while (0)
2487 
2488 #endif
2489 
2490 extern void ext4_update_dynamic_rev(struct super_block *sb);
2491 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2492 					__u32 compat);
2493 extern int ext4_update_rocompat_feature(handle_t *handle,
2494 					struct super_block *sb,	__u32 rocompat);
2495 extern int ext4_update_incompat_feature(handle_t *handle,
2496 					struct super_block *sb,	__u32 incompat);
2497 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2498 				      struct ext4_group_desc *bg);
2499 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2500 				      struct ext4_group_desc *bg);
2501 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2502 				     struct ext4_group_desc *bg);
2503 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2504 				      struct ext4_group_desc *bg);
2505 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2506 				 struct ext4_group_desc *bg);
2507 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2508 				struct ext4_group_desc *bg);
2509 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2510 				   struct ext4_group_desc *bg);
2511 extern void ext4_block_bitmap_set(struct super_block *sb,
2512 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2513 extern void ext4_inode_bitmap_set(struct super_block *sb,
2514 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2515 extern void ext4_inode_table_set(struct super_block *sb,
2516 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2517 extern void ext4_free_group_clusters_set(struct super_block *sb,
2518 					 struct ext4_group_desc *bg,
2519 					 __u32 count);
2520 extern void ext4_free_inodes_set(struct super_block *sb,
2521 				struct ext4_group_desc *bg, __u32 count);
2522 extern void ext4_used_dirs_set(struct super_block *sb,
2523 				struct ext4_group_desc *bg, __u32 count);
2524 extern void ext4_itable_unused_set(struct super_block *sb,
2525 				   struct ext4_group_desc *bg, __u32 count);
2526 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2527 				       struct ext4_group_desc *gdp);
2528 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2529 				     struct ext4_group_desc *gdp);
2530 extern int ext4_register_li_request(struct super_block *sb,
2531 				    ext4_group_t first_not_zeroed);
2532 
2533 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2534 {
2535 	return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2536 					  EXT4_FEATURE_RO_COMPAT_GDT_CSUM) ||
2537 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
2538 }
2539 
2540 static inline int ext4_has_metadata_csum(struct super_block *sb)
2541 {
2542 	WARN_ON_ONCE(EXT4_HAS_RO_COMPAT_FEATURE(sb,
2543 			EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
2544 		     !EXT4_SB(sb)->s_chksum_driver);
2545 
2546 	return (EXT4_SB(sb)->s_chksum_driver != NULL);
2547 }
2548 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2549 {
2550 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2551 		le32_to_cpu(es->s_blocks_count_lo);
2552 }
2553 
2554 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2555 {
2556 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2557 		le32_to_cpu(es->s_r_blocks_count_lo);
2558 }
2559 
2560 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2561 {
2562 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2563 		le32_to_cpu(es->s_free_blocks_count_lo);
2564 }
2565 
2566 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2567 					 ext4_fsblk_t blk)
2568 {
2569 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2570 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2571 }
2572 
2573 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2574 					      ext4_fsblk_t blk)
2575 {
2576 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2577 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2578 }
2579 
2580 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2581 					   ext4_fsblk_t blk)
2582 {
2583 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2584 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2585 }
2586 
2587 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2588 {
2589 	if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2590 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2591 			le32_to_cpu(raw_inode->i_size_lo);
2592 	else
2593 		return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2594 }
2595 
2596 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2597 {
2598 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2599 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2600 }
2601 
2602 static inline
2603 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2604 					    ext4_group_t group)
2605 {
2606 	 struct ext4_group_info ***grp_info;
2607 	 long indexv, indexh;
2608 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2609 	 grp_info = EXT4_SB(sb)->s_group_info;
2610 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2611 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2612 	 return grp_info[indexv][indexh];
2613 }
2614 
2615 /*
2616  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2617  * the locking protocol documented in the comments of ext4_group_add()
2618  * in resize.c
2619  */
2620 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2621 {
2622 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2623 
2624 	smp_rmb();
2625 	return ngroups;
2626 }
2627 
2628 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2629 					     ext4_group_t block_group)
2630 {
2631 	return block_group >> sbi->s_log_groups_per_flex;
2632 }
2633 
2634 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2635 {
2636 	return 1 << sbi->s_log_groups_per_flex;
2637 }
2638 
2639 #define ext4_std_error(sb, errno)				\
2640 do {								\
2641 	if ((errno))						\
2642 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2643 } while (0)
2644 
2645 #ifdef CONFIG_SMP
2646 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2647  * counters. So we need to make sure we have free clusters more
2648  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2649  */
2650 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2651 #else
2652 #define EXT4_FREECLUSTERS_WATERMARK 0
2653 #endif
2654 
2655 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2656 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2657 {
2658 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2659 		     !mutex_is_locked(&inode->i_mutex));
2660 	down_write(&EXT4_I(inode)->i_data_sem);
2661 	if (newsize > EXT4_I(inode)->i_disksize)
2662 		EXT4_I(inode)->i_disksize = newsize;
2663 	up_write(&EXT4_I(inode)->i_data_sem);
2664 }
2665 
2666 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2667 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2668 {
2669 	int changed = 0;
2670 
2671 	if (newsize > inode->i_size) {
2672 		i_size_write(inode, newsize);
2673 		changed = 1;
2674 	}
2675 	if (newsize > EXT4_I(inode)->i_disksize) {
2676 		ext4_update_i_disksize(inode, newsize);
2677 		changed |= 2;
2678 	}
2679 	return changed;
2680 }
2681 
2682 struct ext4_group_info {
2683 	unsigned long   bb_state;
2684 	struct rb_root  bb_free_root;
2685 	ext4_grpblk_t	bb_first_free;	/* first free block */
2686 	ext4_grpblk_t	bb_free;	/* total free blocks */
2687 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2688 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2689 	struct          list_head bb_prealloc_list;
2690 #ifdef DOUBLE_CHECK
2691 	void            *bb_bitmap;
2692 #endif
2693 	struct rw_semaphore alloc_sem;
2694 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2695 					 * regions, index is order.
2696 					 * bb_counters[3] = 5 means
2697 					 * 5 free 8-block regions. */
2698 };
2699 
2700 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2701 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2702 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2703 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2704 
2705 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2706 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2707 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2708 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2709 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2710 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2711 
2712 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2713 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2714 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2715 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2716 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2717 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2718 
2719 #define EXT4_MAX_CONTENTION		8
2720 #define EXT4_CONTENTION_THRESHOLD	2
2721 
2722 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2723 					      ext4_group_t group)
2724 {
2725 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2726 }
2727 
2728 /*
2729  * Returns true if the filesystem is busy enough that attempts to
2730  * access the block group locks has run into contention.
2731  */
2732 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2733 {
2734 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2735 }
2736 
2737 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2738 {
2739 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2740 	if (spin_trylock(lock))
2741 		/*
2742 		 * We're able to grab the lock right away, so drop the
2743 		 * lock contention counter.
2744 		 */
2745 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2746 	else {
2747 		/*
2748 		 * The lock is busy, so bump the contention counter,
2749 		 * and then wait on the spin lock.
2750 		 */
2751 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2752 				  EXT4_MAX_CONTENTION);
2753 		spin_lock(lock);
2754 	}
2755 }
2756 
2757 static inline void ext4_unlock_group(struct super_block *sb,
2758 					ext4_group_t group)
2759 {
2760 	spin_unlock(ext4_group_lock_ptr(sb, group));
2761 }
2762 
2763 /*
2764  * Block validity checking
2765  */
2766 #define ext4_check_indirect_blockref(inode, bh)				\
2767 	ext4_check_blockref(__func__, __LINE__, inode,			\
2768 			    (__le32 *)(bh)->b_data,			\
2769 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2770 
2771 #define ext4_ind_check_inode(inode)					\
2772 	ext4_check_blockref(__func__, __LINE__, inode,			\
2773 			    EXT4_I(inode)->i_data,			\
2774 			    EXT4_NDIR_BLOCKS)
2775 
2776 /*
2777  * Inodes and files operations
2778  */
2779 
2780 /* dir.c */
2781 extern const struct file_operations ext4_dir_operations;
2782 
2783 /* file.c */
2784 extern const struct inode_operations ext4_file_inode_operations;
2785 extern const struct file_operations ext4_file_operations;
2786 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2787 
2788 /* inline.c */
2789 extern int ext4_get_max_inline_size(struct inode *inode);
2790 extern int ext4_find_inline_data_nolock(struct inode *inode);
2791 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2792 				 unsigned int len);
2793 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2794 
2795 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2796 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2797 					 struct inode *inode,
2798 					 loff_t pos, unsigned len,
2799 					 unsigned flags,
2800 					 struct page **pagep);
2801 extern int ext4_write_inline_data_end(struct inode *inode,
2802 				      loff_t pos, unsigned len,
2803 				      unsigned copied,
2804 				      struct page *page);
2805 extern struct buffer_head *
2806 ext4_journalled_write_inline_data(struct inode *inode,
2807 				  unsigned len,
2808 				  struct page *page);
2809 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
2810 					   struct inode *inode,
2811 					   loff_t pos, unsigned len,
2812 					   unsigned flags,
2813 					   struct page **pagep,
2814 					   void **fsdata);
2815 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
2816 					 unsigned len, unsigned copied,
2817 					 struct page *page);
2818 extern int ext4_try_add_inline_entry(handle_t *handle,
2819 				     struct ext4_filename *fname,
2820 				     struct dentry *dentry,
2821 				     struct inode *inode);
2822 extern int ext4_try_create_inline_dir(handle_t *handle,
2823 				      struct inode *parent,
2824 				      struct inode *inode);
2825 extern int ext4_read_inline_dir(struct file *filp,
2826 				struct dir_context *ctx,
2827 				int *has_inline_data);
2828 extern int htree_inlinedir_to_tree(struct file *dir_file,
2829 				   struct inode *dir, ext4_lblk_t block,
2830 				   struct dx_hash_info *hinfo,
2831 				   __u32 start_hash, __u32 start_minor_hash,
2832 				   int *has_inline_data);
2833 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
2834 					struct ext4_filename *fname,
2835 					const struct qstr *d_name,
2836 					struct ext4_dir_entry_2 **res_dir,
2837 					int *has_inline_data);
2838 extern int ext4_delete_inline_entry(handle_t *handle,
2839 				    struct inode *dir,
2840 				    struct ext4_dir_entry_2 *de_del,
2841 				    struct buffer_head *bh,
2842 				    int *has_inline_data);
2843 extern int empty_inline_dir(struct inode *dir, int *has_inline_data);
2844 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
2845 					struct ext4_dir_entry_2 **parent_de,
2846 					int *retval);
2847 extern int ext4_inline_data_fiemap(struct inode *inode,
2848 				   struct fiemap_extent_info *fieinfo,
2849 				   int *has_inline, __u64 start, __u64 len);
2850 extern int ext4_try_to_evict_inline_data(handle_t *handle,
2851 					 struct inode *inode,
2852 					 int needed);
2853 extern void ext4_inline_data_truncate(struct inode *inode, int *has_inline);
2854 
2855 extern int ext4_convert_inline_data(struct inode *inode);
2856 
2857 static inline int ext4_has_inline_data(struct inode *inode)
2858 {
2859 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
2860 	       EXT4_I(inode)->i_inline_off;
2861 }
2862 
2863 /* namei.c */
2864 extern const struct inode_operations ext4_dir_inode_operations;
2865 extern const struct inode_operations ext4_special_inode_operations;
2866 extern struct dentry *ext4_get_parent(struct dentry *child);
2867 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2868 				 struct ext4_dir_entry_2 *de,
2869 				 int blocksize, int csum_size,
2870 				 unsigned int parent_ino, int dotdot_real_len);
2871 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
2872 				   unsigned int blocksize);
2873 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
2874 					 struct inode *inode,
2875 					 struct buffer_head *bh);
2876 #define S_SHIFT 12
2877 static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
2878 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
2879 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
2880 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
2881 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
2882 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
2883 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
2884 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
2885 };
2886 
2887 static inline void ext4_set_de_type(struct super_block *sb,
2888 				struct ext4_dir_entry_2 *de,
2889 				umode_t mode) {
2890 	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE))
2891 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
2892 }
2893 
2894 /* readpages.c */
2895 extern int ext4_mpage_readpages(struct address_space *mapping,
2896 				struct list_head *pages, struct page *page,
2897 				unsigned nr_pages);
2898 
2899 /* symlink.c */
2900 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
2901 extern const struct inode_operations ext4_symlink_inode_operations;
2902 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2903 
2904 /* block_validity */
2905 extern void ext4_release_system_zone(struct super_block *sb);
2906 extern int ext4_setup_system_zone(struct super_block *sb);
2907 extern int __init ext4_init_system_zone(void);
2908 extern void ext4_exit_system_zone(void);
2909 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2910 				 ext4_fsblk_t start_blk,
2911 				 unsigned int count);
2912 extern int ext4_check_blockref(const char *, unsigned int,
2913 			       struct inode *, __le32 *, unsigned int);
2914 
2915 /* extents.c */
2916 struct ext4_ext_path;
2917 struct ext4_extent;
2918 
2919 /*
2920  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
2921  * __le32.
2922  */
2923 #define EXT_MAX_BLOCKS	0xffffffff
2924 
2925 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2926 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2927 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
2928 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2929 			       struct ext4_map_blocks *map, int flags);
2930 extern void ext4_ext_truncate(handle_t *, struct inode *);
2931 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
2932 				 ext4_lblk_t end);
2933 extern void ext4_ext_init(struct super_block *);
2934 extern void ext4_ext_release(struct super_block *);
2935 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2936 			  loff_t len);
2937 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
2938 					  loff_t offset, ssize_t len);
2939 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2940 			   struct ext4_map_blocks *map, int flags);
2941 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
2942 					 ext4_lblk_t lblocks);
2943 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
2944 						   int num,
2945 						   struct ext4_ext_path *path);
2946 extern int ext4_can_extents_be_merged(struct inode *inode,
2947 				      struct ext4_extent *ex1,
2948 				      struct ext4_extent *ex2);
2949 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
2950 				  struct ext4_ext_path **,
2951 				  struct ext4_extent *, int);
2952 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
2953 					      struct ext4_ext_path **,
2954 					      int flags);
2955 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
2956 extern int ext4_ext_check_inode(struct inode *inode);
2957 extern int ext4_find_delalloc_range(struct inode *inode,
2958 				    ext4_lblk_t lblk_start,
2959 				    ext4_lblk_t lblk_end);
2960 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
2961 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
2962 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2963 			__u64 start, __u64 len);
2964 extern int ext4_ext_precache(struct inode *inode);
2965 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
2966 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
2967 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
2968 				struct inode *inode2, ext4_lblk_t lblk1,
2969 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
2970 			     int mark_unwritten,int *err);
2971 
2972 /* move_extent.c */
2973 extern void ext4_double_down_write_data_sem(struct inode *first,
2974 					    struct inode *second);
2975 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
2976 					  struct inode *donor_inode);
2977 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2978 			     __u64 start_orig, __u64 start_donor,
2979 			     __u64 len, __u64 *moved_len);
2980 
2981 /* page-io.c */
2982 extern int __init ext4_init_pageio(void);
2983 extern void ext4_exit_pageio(void);
2984 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2985 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
2986 extern int ext4_put_io_end(ext4_io_end_t *io_end);
2987 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
2988 extern void ext4_io_submit_init(struct ext4_io_submit *io,
2989 				struct writeback_control *wbc);
2990 extern void ext4_end_io_rsv_work(struct work_struct *work);
2991 extern void ext4_io_submit(struct ext4_io_submit *io);
2992 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2993 			       struct page *page,
2994 			       int len,
2995 			       struct writeback_control *wbc,
2996 			       bool keep_towrite);
2997 
2998 /* mmp.c */
2999 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3000 
3001 /*
3002  * Add new method to test whether block and inode bitmaps are properly
3003  * initialized. With uninit_bg reading the block from disk is not enough
3004  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3005  */
3006 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3007 
3008 static inline int bitmap_uptodate(struct buffer_head *bh)
3009 {
3010 	return (buffer_uptodate(bh) &&
3011 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3012 }
3013 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3014 {
3015 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3016 }
3017 
3018 /*
3019  * Disable DIO read nolock optimization, so new dioreaders will be forced
3020  * to grab i_mutex
3021  */
3022 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
3023 {
3024 	ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3025 	smp_mb();
3026 }
3027 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
3028 {
3029 	smp_mb();
3030 	ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3031 }
3032 
3033 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3034 
3035 /* For ioend & aio unwritten conversion wait queues */
3036 #define EXT4_WQ_HASH_SZ		37
3037 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3038 					    EXT4_WQ_HASH_SZ])
3039 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
3040 					     EXT4_WQ_HASH_SZ])
3041 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3042 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
3043 
3044 #define EXT4_RESIZING	0
3045 extern int ext4_resize_begin(struct super_block *sb);
3046 extern void ext4_resize_end(struct super_block *sb);
3047 
3048 #endif	/* __KERNEL__ */
3049 
3050 #endif	/* _EXT4_H */
3051