xref: /openbmc/linux/fs/ext4/ext4.h (revision bc5aa3a0)
1 /*
2  *  ext4.h
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/include/linux/minix_fs.h
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  */
15 
16 #ifndef _EXT4_H
17 #define _EXT4_H
18 
19 #include <linux/types.h>
20 #include <linux/blkdev.h>
21 #include <linux/magic.h>
22 #include <linux/jbd2.h>
23 #include <linux/quota.h>
24 #include <linux/rwsem.h>
25 #include <linux/rbtree.h>
26 #include <linux/seqlock.h>
27 #include <linux/mutex.h>
28 #include <linux/timer.h>
29 #include <linux/version.h>
30 #include <linux/wait.h>
31 #include <linux/blockgroup_lock.h>
32 #include <linux/percpu_counter.h>
33 #include <linux/ratelimit.h>
34 #include <crypto/hash.h>
35 #include <linux/fscrypto.h>
36 #include <linux/falloc.h>
37 #include <linux/percpu-rwsem.h>
38 #ifdef __KERNEL__
39 #include <linux/compat.h>
40 #endif
41 
42 /*
43  * The fourth extended filesystem constants/structures
44  */
45 
46 /*
47  * with AGGRESSIVE_CHECK allocator runs consistency checks over
48  * structures. these checks slow things down a lot
49  */
50 #define AGGRESSIVE_CHECK__
51 
52 /*
53  * with DOUBLE_CHECK defined mballoc creates persistent in-core
54  * bitmaps, maintains and uses them to check for double allocations
55  */
56 #define DOUBLE_CHECK__
57 
58 /*
59  * Define EXT4FS_DEBUG to produce debug messages
60  */
61 #undef EXT4FS_DEBUG
62 
63 /*
64  * Debug code
65  */
66 #ifdef EXT4FS_DEBUG
67 #define ext4_debug(f, a...)						\
68 	do {								\
69 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
70 			__FILE__, __LINE__, __func__);			\
71 		printk(KERN_DEBUG f, ## a);				\
72 	} while (0)
73 #else
74 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
75 #endif
76 
77 /*
78  * Turn on EXT_DEBUG to get lots of info about extents operations.
79  */
80 #define EXT_DEBUG__
81 #ifdef EXT_DEBUG
82 #define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
83 #else
84 #define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
85 #endif
86 
87 /* data type for block offset of block group */
88 typedef int ext4_grpblk_t;
89 
90 /* data type for filesystem-wide blocks number */
91 typedef unsigned long long ext4_fsblk_t;
92 
93 /* data type for file logical block number */
94 typedef __u32 ext4_lblk_t;
95 
96 /* data type for block group number */
97 typedef unsigned int ext4_group_t;
98 
99 enum SHIFT_DIRECTION {
100 	SHIFT_LEFT = 0,
101 	SHIFT_RIGHT,
102 };
103 
104 /*
105  * Flags used in mballoc's allocation_context flags field.
106  *
107  * Also used to show what's going on for debugging purposes when the
108  * flag field is exported via the traceport interface
109  */
110 
111 /* prefer goal again. length */
112 #define EXT4_MB_HINT_MERGE		0x0001
113 /* blocks already reserved */
114 #define EXT4_MB_HINT_RESERVED		0x0002
115 /* metadata is being allocated */
116 #define EXT4_MB_HINT_METADATA		0x0004
117 /* first blocks in the file */
118 #define EXT4_MB_HINT_FIRST		0x0008
119 /* search for the best chunk */
120 #define EXT4_MB_HINT_BEST		0x0010
121 /* data is being allocated */
122 #define EXT4_MB_HINT_DATA		0x0020
123 /* don't preallocate (for tails) */
124 #define EXT4_MB_HINT_NOPREALLOC		0x0040
125 /* allocate for locality group */
126 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
127 /* allocate goal blocks or none */
128 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
129 /* goal is meaningful */
130 #define EXT4_MB_HINT_TRY_GOAL		0x0200
131 /* blocks already pre-reserved by delayed allocation */
132 #define EXT4_MB_DELALLOC_RESERVED	0x0400
133 /* We are doing stream allocation */
134 #define EXT4_MB_STREAM_ALLOC		0x0800
135 /* Use reserved root blocks if needed */
136 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
137 /* Use blocks from reserved pool */
138 #define EXT4_MB_USE_RESERVED		0x2000
139 
140 struct ext4_allocation_request {
141 	/* target inode for block we're allocating */
142 	struct inode *inode;
143 	/* how many blocks we want to allocate */
144 	unsigned int len;
145 	/* logical block in target inode */
146 	ext4_lblk_t logical;
147 	/* the closest logical allocated block to the left */
148 	ext4_lblk_t lleft;
149 	/* the closest logical allocated block to the right */
150 	ext4_lblk_t lright;
151 	/* phys. target (a hint) */
152 	ext4_fsblk_t goal;
153 	/* phys. block for the closest logical allocated block to the left */
154 	ext4_fsblk_t pleft;
155 	/* phys. block for the closest logical allocated block to the right */
156 	ext4_fsblk_t pright;
157 	/* flags. see above EXT4_MB_HINT_* */
158 	unsigned int flags;
159 };
160 
161 /*
162  * Logical to physical block mapping, used by ext4_map_blocks()
163  *
164  * This structure is used to pass requests into ext4_map_blocks() as
165  * well as to store the information returned by ext4_map_blocks().  It
166  * takes less room on the stack than a struct buffer_head.
167  */
168 #define EXT4_MAP_NEW		(1 << BH_New)
169 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
170 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
171 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
172 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
173 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
174 
175 struct ext4_map_blocks {
176 	ext4_fsblk_t m_pblk;
177 	ext4_lblk_t m_lblk;
178 	unsigned int m_len;
179 	unsigned int m_flags;
180 };
181 
182 /*
183  * Flags for ext4_io_end->flags
184  */
185 #define	EXT4_IO_END_UNWRITTEN	0x0001
186 
187 /*
188  * For converting unwritten extents on a work queue. 'handle' is used for
189  * buffered writeback.
190  */
191 typedef struct ext4_io_end {
192 	struct list_head	list;		/* per-file finished IO list */
193 	handle_t		*handle;	/* handle reserved for extent
194 						 * conversion */
195 	struct inode		*inode;		/* file being written to */
196 	struct bio		*bio;		/* Linked list of completed
197 						 * bios covering the extent */
198 	unsigned int		flag;		/* unwritten or not */
199 	atomic_t		count;		/* reference counter */
200 	loff_t			offset;		/* offset in the file */
201 	ssize_t			size;		/* size of the extent */
202 } ext4_io_end_t;
203 
204 struct ext4_io_submit {
205 	struct writeback_control *io_wbc;
206 	struct bio		*io_bio;
207 	ext4_io_end_t		*io_end;
208 	sector_t		io_next_block;
209 };
210 
211 /*
212  * Special inodes numbers
213  */
214 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
215 #define EXT4_ROOT_INO		 2	/* Root inode */
216 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
217 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
218 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
219 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
220 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
221 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
222 
223 /* First non-reserved inode for old ext4 filesystems */
224 #define EXT4_GOOD_OLD_FIRST_INO	11
225 
226 /*
227  * Maximal count of links to a file
228  */
229 #define EXT4_LINK_MAX		65000
230 
231 /*
232  * Macro-instructions used to manage several block sizes
233  */
234 #define EXT4_MIN_BLOCK_SIZE		1024
235 #define	EXT4_MAX_BLOCK_SIZE		65536
236 #define EXT4_MIN_BLOCK_LOG_SIZE		10
237 #define EXT4_MAX_BLOCK_LOG_SIZE		16
238 #ifdef __KERNEL__
239 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
240 #else
241 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
242 #endif
243 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
244 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
245 					 EXT4_SB(s)->s_cluster_bits)
246 #ifdef __KERNEL__
247 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
248 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
249 #else
250 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
251 #endif
252 #ifdef __KERNEL__
253 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
254 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
255 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
256 #else
257 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
258 				 EXT4_GOOD_OLD_INODE_SIZE : \
259 				 (s)->s_inode_size)
260 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
261 				 EXT4_GOOD_OLD_FIRST_INO : \
262 				 (s)->s_first_ino)
263 #endif
264 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
265 
266 /* Translate a block number to a cluster number */
267 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
268 /* Translate a cluster number to a block number */
269 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
270 /* Translate # of blks to # of clusters */
271 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
272 				 (sbi)->s_cluster_bits)
273 /* Mask out the low bits to get the starting block of the cluster */
274 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
275 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
276 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
277 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
278 /* Get the cluster offset */
279 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
280 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
281 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
282 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
283 
284 /*
285  * Structure of a blocks group descriptor
286  */
287 struct ext4_group_desc
288 {
289 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
290 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
291 	__le32	bg_inode_table_lo;	/* Inodes table block */
292 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
293 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
294 	__le16	bg_used_dirs_count_lo;	/* Directories count */
295 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
296 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
297 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
298 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
299 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
300 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
301 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
302 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
303 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
304 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
305 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
306 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
307 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
308 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
309 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
310 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
311 	__u32   bg_reserved;
312 };
313 
314 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
315 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
316 	 sizeof(__le16))
317 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
318 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
319 	 sizeof(__le16))
320 
321 /*
322  * Structure of a flex block group info
323  */
324 
325 struct flex_groups {
326 	atomic64_t	free_clusters;
327 	atomic_t	free_inodes;
328 	atomic_t	used_dirs;
329 };
330 
331 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
332 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
333 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
334 
335 /*
336  * Macro-instructions used to manage group descriptors
337  */
338 #define EXT4_MIN_DESC_SIZE		32
339 #define EXT4_MIN_DESC_SIZE_64BIT	64
340 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
341 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
342 #ifdef __KERNEL__
343 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
344 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
345 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
346 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
347 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
348 #else
349 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
350 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
351 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
352 #endif
353 
354 /*
355  * Constants relative to the data blocks
356  */
357 #define	EXT4_NDIR_BLOCKS		12
358 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
359 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
360 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
361 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
362 
363 /*
364  * Inode flags
365  */
366 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
367 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
368 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
369 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
370 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
371 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
372 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
373 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
374 /* Reserved for compression usage... */
375 #define EXT4_DIRTY_FL			0x00000100
376 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
377 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
378 	/* nb: was previously EXT2_ECOMPR_FL */
379 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
380 /* End compression flags --- maybe not all used */
381 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
382 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
383 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
384 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
385 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
386 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
387 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
388 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
389 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
390 #define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
391 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
392 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
393 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
394 
395 #define EXT4_FL_USER_VISIBLE		0x304BDFFF /* User visible flags */
396 #define EXT4_FL_USER_MODIFIABLE		0x204380FF /* User modifiable flags */
397 
398 #define EXT4_FL_XFLAG_VISIBLE		(EXT4_SYNC_FL | \
399 					 EXT4_IMMUTABLE_FL | \
400 					 EXT4_APPEND_FL | \
401 					 EXT4_NODUMP_FL | \
402 					 EXT4_NOATIME_FL | \
403 					 EXT4_PROJINHERIT_FL)
404 
405 /* Flags that should be inherited by new inodes from their parent. */
406 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
407 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
408 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
409 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
410 			   EXT4_PROJINHERIT_FL)
411 
412 /* Flags that are appropriate for regular files (all but dir-specific ones). */
413 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
414 
415 /* Flags that are appropriate for non-directories/regular files. */
416 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
417 
418 /* Mask out flags that are inappropriate for the given type of inode. */
419 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
420 {
421 	if (S_ISDIR(mode))
422 		return flags;
423 	else if (S_ISREG(mode))
424 		return flags & EXT4_REG_FLMASK;
425 	else
426 		return flags & EXT4_OTHER_FLMASK;
427 }
428 
429 /*
430  * Inode flags used for atomic set/get
431  */
432 enum {
433 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
434 	EXT4_INODE_UNRM		= 1,	/* Undelete */
435 	EXT4_INODE_COMPR	= 2,	/* Compress file */
436 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
437 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
438 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
439 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
440 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
441 /* Reserved for compression usage... */
442 	EXT4_INODE_DIRTY	= 8,
443 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
444 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
445 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
446 /* End compression flags --- maybe not all used */
447 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
448 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
449 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
450 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
451 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
452 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
453 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
454 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
455 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
456 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
457 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
458 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
459 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
460 };
461 
462 /*
463  * Since it's pretty easy to mix up bit numbers and hex values, we use a
464  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
465  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
466  * any extra space in the compiled kernel image, otherwise, the build will fail.
467  * It's important that these values are the same, since we are using
468  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
469  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
470  * values found in ext2, ext3 and ext4 filesystems, and of course the values
471  * defined in e2fsprogs.
472  *
473  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
474  */
475 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
476 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
477 
478 static inline void ext4_check_flag_values(void)
479 {
480 	CHECK_FLAG_VALUE(SECRM);
481 	CHECK_FLAG_VALUE(UNRM);
482 	CHECK_FLAG_VALUE(COMPR);
483 	CHECK_FLAG_VALUE(SYNC);
484 	CHECK_FLAG_VALUE(IMMUTABLE);
485 	CHECK_FLAG_VALUE(APPEND);
486 	CHECK_FLAG_VALUE(NODUMP);
487 	CHECK_FLAG_VALUE(NOATIME);
488 	CHECK_FLAG_VALUE(DIRTY);
489 	CHECK_FLAG_VALUE(COMPRBLK);
490 	CHECK_FLAG_VALUE(NOCOMPR);
491 	CHECK_FLAG_VALUE(ENCRYPT);
492 	CHECK_FLAG_VALUE(INDEX);
493 	CHECK_FLAG_VALUE(IMAGIC);
494 	CHECK_FLAG_VALUE(JOURNAL_DATA);
495 	CHECK_FLAG_VALUE(NOTAIL);
496 	CHECK_FLAG_VALUE(DIRSYNC);
497 	CHECK_FLAG_VALUE(TOPDIR);
498 	CHECK_FLAG_VALUE(HUGE_FILE);
499 	CHECK_FLAG_VALUE(EXTENTS);
500 	CHECK_FLAG_VALUE(EA_INODE);
501 	CHECK_FLAG_VALUE(EOFBLOCKS);
502 	CHECK_FLAG_VALUE(INLINE_DATA);
503 	CHECK_FLAG_VALUE(PROJINHERIT);
504 	CHECK_FLAG_VALUE(RESERVED);
505 }
506 
507 /* Used to pass group descriptor data when online resize is done */
508 struct ext4_new_group_input {
509 	__u32 group;		/* Group number for this data */
510 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
511 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
512 	__u64 inode_table;	/* Absolute block number of inode table start */
513 	__u32 blocks_count;	/* Total number of blocks in this group */
514 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
515 	__u16 unused;
516 };
517 
518 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
519 struct compat_ext4_new_group_input {
520 	u32 group;
521 	compat_u64 block_bitmap;
522 	compat_u64 inode_bitmap;
523 	compat_u64 inode_table;
524 	u32 blocks_count;
525 	u16 reserved_blocks;
526 	u16 unused;
527 };
528 #endif
529 
530 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
531 struct ext4_new_group_data {
532 	__u32 group;
533 	__u64 block_bitmap;
534 	__u64 inode_bitmap;
535 	__u64 inode_table;
536 	__u32 blocks_count;
537 	__u16 reserved_blocks;
538 	__u16 unused;
539 	__u32 free_blocks_count;
540 };
541 
542 /* Indexes used to index group tables in ext4_new_group_data */
543 enum {
544 	BLOCK_BITMAP = 0,	/* block bitmap */
545 	INODE_BITMAP,		/* inode bitmap */
546 	INODE_TABLE,		/* inode tables */
547 	GROUP_TABLE_COUNT,
548 };
549 
550 /*
551  * Flags used by ext4_map_blocks()
552  */
553 	/* Allocate any needed blocks and/or convert an unwritten
554 	   extent to be an initialized ext4 */
555 #define EXT4_GET_BLOCKS_CREATE			0x0001
556 	/* Request the creation of an unwritten extent */
557 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
558 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
559 						 EXT4_GET_BLOCKS_CREATE)
560 	/* Caller is from the delayed allocation writeout path
561 	 * finally doing the actual allocation of delayed blocks */
562 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
563 	/* caller is from the direct IO path, request to creation of an
564 	unwritten extents if not allocated, split the unwritten
565 	extent if blocks has been preallocated already*/
566 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
567 #define EXT4_GET_BLOCKS_CONVERT			0x0010
568 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
569 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
570 	/* Convert extent to initialized after IO complete */
571 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
572 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
573 	/* Eventual metadata allocation (due to growing extent tree)
574 	 * should not fail, so try to use reserved blocks for that.*/
575 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
576 	/* Don't normalize allocation size (used for fallocate) */
577 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
578 	/* Request will not result in inode size update (user for fallocate) */
579 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
580 	/* Convert written extents to unwritten */
581 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
582 	/* Write zeros to newly created written extents */
583 #define EXT4_GET_BLOCKS_ZERO			0x0200
584 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
585 					EXT4_GET_BLOCKS_ZERO)
586 	/* Caller will submit data before dropping transaction handle. This
587 	 * allows jbd2 to avoid submitting data before commit. */
588 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
589 
590 /*
591  * The bit position of these flags must not overlap with any of the
592  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
593  * read_extent_tree_block(), ext4_split_extent_at(),
594  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
595  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
596  * caching the extents when reading from the extent tree while a
597  * truncate or punch hole operation is in progress.
598  */
599 #define EXT4_EX_NOCACHE				0x40000000
600 #define EXT4_EX_FORCE_CACHE			0x20000000
601 
602 /*
603  * Flags used by ext4_free_blocks
604  */
605 #define EXT4_FREE_BLOCKS_METADATA	0x0001
606 #define EXT4_FREE_BLOCKS_FORGET		0x0002
607 #define EXT4_FREE_BLOCKS_VALIDATED	0x0004
608 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE	0x0008
609 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
610 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
611 
612 /*
613  * ioctl commands
614  */
615 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
616 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
617 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
618 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
619 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
620 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
621 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
622 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
623 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
624 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
625 #define EXT4_IOC_MIGRATE		_IO('f', 9)
626  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
627  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
628 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
629 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
630 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
631 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
632 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
633 #define EXT4_IOC_SET_ENCRYPTION_POLICY	FS_IOC_SET_ENCRYPTION_POLICY
634 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	FS_IOC_GET_ENCRYPTION_PWSALT
635 #define EXT4_IOC_GET_ENCRYPTION_POLICY	FS_IOC_GET_ENCRYPTION_POLICY
636 
637 #ifndef FS_IOC_FSGETXATTR
638 /* Until the uapi changes get merged for project quota... */
639 
640 #define FS_IOC_FSGETXATTR		_IOR('X', 31, struct fsxattr)
641 #define FS_IOC_FSSETXATTR		_IOW('X', 32, struct fsxattr)
642 
643 /*
644  * Structure for FS_IOC_FSGETXATTR and FS_IOC_FSSETXATTR.
645  */
646 struct fsxattr {
647 	__u32		fsx_xflags;	/* xflags field value (get/set) */
648 	__u32		fsx_extsize;	/* extsize field value (get/set)*/
649 	__u32		fsx_nextents;	/* nextents field value (get)	*/
650 	__u32		fsx_projid;	/* project identifier (get/set) */
651 	unsigned char	fsx_pad[12];
652 };
653 
654 /*
655  * Flags for the fsx_xflags field
656  */
657 #define FS_XFLAG_REALTIME	0x00000001	/* data in realtime volume */
658 #define FS_XFLAG_PREALLOC	0x00000002	/* preallocated file extents */
659 #define FS_XFLAG_IMMUTABLE	0x00000008	/* file cannot be modified */
660 #define FS_XFLAG_APPEND		0x00000010	/* all writes append */
661 #define FS_XFLAG_SYNC		0x00000020	/* all writes synchronous */
662 #define FS_XFLAG_NOATIME	0x00000040	/* do not update access time */
663 #define FS_XFLAG_NODUMP		0x00000080	/* do not include in backups */
664 #define FS_XFLAG_RTINHERIT	0x00000100	/* create with rt bit set */
665 #define FS_XFLAG_PROJINHERIT	0x00000200	/* create with parents projid */
666 #define FS_XFLAG_NOSYMLINKS	0x00000400	/* disallow symlink creation */
667 #define FS_XFLAG_EXTSIZE	0x00000800	/* extent size allocator hint */
668 #define FS_XFLAG_EXTSZINHERIT	0x00001000	/* inherit inode extent size */
669 #define FS_XFLAG_NODEFRAG	0x00002000  	/* do not defragment */
670 #define FS_XFLAG_FILESTREAM	0x00004000	/* use filestream allocator */
671 #define FS_XFLAG_HASATTR	0x80000000	/* no DIFLAG for this */
672 #endif /* !defined(FS_IOC_FSGETXATTR) */
673 
674 #define EXT4_IOC_FSGETXATTR		FS_IOC_FSGETXATTR
675 #define EXT4_IOC_FSSETXATTR		FS_IOC_FSSETXATTR
676 
677 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
678 /*
679  * ioctl commands in 32 bit emulation
680  */
681 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
682 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
683 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
684 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
685 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
686 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
687 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
688 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
689 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
690 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
691 #endif
692 
693 /* Max physical block we can address w/o extents */
694 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
695 
696 /*
697  * Structure of an inode on the disk
698  */
699 struct ext4_inode {
700 	__le16	i_mode;		/* File mode */
701 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
702 	__le32	i_size_lo;	/* Size in bytes */
703 	__le32	i_atime;	/* Access time */
704 	__le32	i_ctime;	/* Inode Change time */
705 	__le32	i_mtime;	/* Modification time */
706 	__le32	i_dtime;	/* Deletion Time */
707 	__le16	i_gid;		/* Low 16 bits of Group Id */
708 	__le16	i_links_count;	/* Links count */
709 	__le32	i_blocks_lo;	/* Blocks count */
710 	__le32	i_flags;	/* File flags */
711 	union {
712 		struct {
713 			__le32  l_i_version;
714 		} linux1;
715 		struct {
716 			__u32  h_i_translator;
717 		} hurd1;
718 		struct {
719 			__u32  m_i_reserved1;
720 		} masix1;
721 	} osd1;				/* OS dependent 1 */
722 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
723 	__le32	i_generation;	/* File version (for NFS) */
724 	__le32	i_file_acl_lo;	/* File ACL */
725 	__le32	i_size_high;
726 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
727 	union {
728 		struct {
729 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
730 			__le16	l_i_file_acl_high;
731 			__le16	l_i_uid_high;	/* these 2 fields */
732 			__le16	l_i_gid_high;	/* were reserved2[0] */
733 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
734 			__le16	l_i_reserved;
735 		} linux2;
736 		struct {
737 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
738 			__u16	h_i_mode_high;
739 			__u16	h_i_uid_high;
740 			__u16	h_i_gid_high;
741 			__u32	h_i_author;
742 		} hurd2;
743 		struct {
744 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
745 			__le16	m_i_file_acl_high;
746 			__u32	m_i_reserved2[2];
747 		} masix2;
748 	} osd2;				/* OS dependent 2 */
749 	__le16	i_extra_isize;
750 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
751 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
752 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
753 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
754 	__le32  i_crtime;       /* File Creation time */
755 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
756 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
757 	__le32	i_projid;	/* Project ID */
758 };
759 
760 struct move_extent {
761 	__u32 reserved;		/* should be zero */
762 	__u32 donor_fd;		/* donor file descriptor */
763 	__u64 orig_start;	/* logical start offset in block for orig */
764 	__u64 donor_start;	/* logical start offset in block for donor */
765 	__u64 len;		/* block length to be moved */
766 	__u64 moved_len;	/* moved block length */
767 };
768 
769 #define EXT4_EPOCH_BITS 2
770 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
771 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
772 
773 /*
774  * Extended fields will fit into an inode if the filesystem was formatted
775  * with large inodes (-I 256 or larger) and there are not currently any EAs
776  * consuming all of the available space. For new inodes we always reserve
777  * enough space for the kernel's known extended fields, but for inodes
778  * created with an old kernel this might not have been the case. None of
779  * the extended inode fields is critical for correct filesystem operation.
780  * This macro checks if a certain field fits in the inode. Note that
781  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
782  */
783 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
784 	((offsetof(typeof(*ext4_inode), field) +	\
785 	  sizeof((ext4_inode)->field))			\
786 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
787 	    (einode)->i_extra_isize))			\
788 
789 /*
790  * We use an encoding that preserves the times for extra epoch "00":
791  *
792  * extra  msb of                         adjust for signed
793  * epoch  32-bit                         32-bit tv_sec to
794  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
795  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
796  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
797  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
798  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
799  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
800  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
801  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
802  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
803  *
804  * Note that previous versions of the kernel on 64-bit systems would
805  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
806  * 1970.  e2fsck will correct this, assuming that it is run on the
807  * affected filesystem before 2242.
808  */
809 
810 static inline __le32 ext4_encode_extra_time(struct timespec *time)
811 {
812 	u32 extra = sizeof(time->tv_sec) > 4 ?
813 		((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK : 0;
814 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
815 }
816 
817 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
818 {
819 	if (unlikely(sizeof(time->tv_sec) > 4 &&
820 			(extra & cpu_to_le32(EXT4_EPOCH_MASK)))) {
821 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,20,0)
822 		/* Handle legacy encoding of pre-1970 dates with epoch
823 		 * bits 1,1.  We assume that by kernel version 4.20,
824 		 * everyone will have run fsck over the affected
825 		 * filesystems to correct the problem.  (This
826 		 * backwards compatibility may be removed before this
827 		 * time, at the discretion of the ext4 developers.)
828 		 */
829 		u64 extra_bits = le32_to_cpu(extra) & EXT4_EPOCH_MASK;
830 		if (extra_bits == 3 && ((time->tv_sec) & 0x80000000) != 0)
831 			extra_bits = 0;
832 		time->tv_sec += extra_bits << 32;
833 #else
834 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
835 #endif
836 	}
837 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
838 }
839 
840 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)			       \
841 do {									       \
842 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	       \
843 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
844 		(raw_inode)->xtime ## _extra =				       \
845 				ext4_encode_extra_time(&(inode)->xtime);       \
846 } while (0)
847 
848 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
849 do {									       \
850 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
851 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
852 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
853 		(raw_inode)->xtime ## _extra =				       \
854 				ext4_encode_extra_time(&(einode)->xtime);      \
855 } while (0)
856 
857 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)			       \
858 do {									       \
859 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
860 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
861 		ext4_decode_extra_time(&(inode)->xtime,			       \
862 				       raw_inode->xtime ## _extra);	       \
863 	else								       \
864 		(inode)->xtime.tv_nsec = 0;				       \
865 } while (0)
866 
867 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
868 do {									       \
869 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
870 		(einode)->xtime.tv_sec = 				       \
871 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
872 	else								       \
873 		(einode)->xtime.tv_sec = 0;				       \
874 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
875 		ext4_decode_extra_time(&(einode)->xtime,		       \
876 				       raw_inode->xtime ## _extra);	       \
877 	else								       \
878 		(einode)->xtime.tv_nsec = 0;				       \
879 } while (0)
880 
881 #define i_disk_version osd1.linux1.l_i_version
882 
883 #if defined(__KERNEL__) || defined(__linux__)
884 #define i_reserved1	osd1.linux1.l_i_reserved1
885 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
886 #define i_blocks_high	osd2.linux2.l_i_blocks_high
887 #define i_uid_low	i_uid
888 #define i_gid_low	i_gid
889 #define i_uid_high	osd2.linux2.l_i_uid_high
890 #define i_gid_high	osd2.linux2.l_i_gid_high
891 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
892 
893 #elif defined(__GNU__)
894 
895 #define i_translator	osd1.hurd1.h_i_translator
896 #define i_uid_high	osd2.hurd2.h_i_uid_high
897 #define i_gid_high	osd2.hurd2.h_i_gid_high
898 #define i_author	osd2.hurd2.h_i_author
899 
900 #elif defined(__masix__)
901 
902 #define i_reserved1	osd1.masix1.m_i_reserved1
903 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
904 #define i_reserved2	osd2.masix2.m_i_reserved2
905 
906 #endif /* defined(__KERNEL__) || defined(__linux__) */
907 
908 #include "extents_status.h"
909 
910 /*
911  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
912  *
913  * These are needed to avoid lockdep false positives when we need to
914  * allocate blocks to the quota inode during ext4_map_blocks(), while
915  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
916  * do quota tracking for the quota inode, this avoids deadlock (as
917  * well as infinite recursion, since it isn't turtles all the way
918  * down...)
919  *
920  *  I_DATA_SEM_NORMAL - Used for most inodes
921  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
922  *			  where the second inode has larger inode number
923  *			  than the first
924  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
925  */
926 enum {
927 	I_DATA_SEM_NORMAL = 0,
928 	I_DATA_SEM_OTHER,
929 	I_DATA_SEM_QUOTA,
930 };
931 
932 
933 /*
934  * fourth extended file system inode data in memory
935  */
936 struct ext4_inode_info {
937 	__le32	i_data[15];	/* unconverted */
938 	__u32	i_dtime;
939 	ext4_fsblk_t	i_file_acl;
940 
941 	/*
942 	 * i_block_group is the number of the block group which contains
943 	 * this file's inode.  Constant across the lifetime of the inode,
944 	 * it is ued for making block allocation decisions - we try to
945 	 * place a file's data blocks near its inode block, and new inodes
946 	 * near to their parent directory's inode.
947 	 */
948 	ext4_group_t	i_block_group;
949 	ext4_lblk_t	i_dir_start_lookup;
950 #if (BITS_PER_LONG < 64)
951 	unsigned long	i_state_flags;		/* Dynamic state flags */
952 #endif
953 	unsigned long	i_flags;
954 
955 	/*
956 	 * Extended attributes can be read independently of the main file
957 	 * data. Taking i_mutex even when reading would cause contention
958 	 * between readers of EAs and writers of regular file data, so
959 	 * instead we synchronize on xattr_sem when reading or changing
960 	 * EAs.
961 	 */
962 	struct rw_semaphore xattr_sem;
963 
964 	struct list_head i_orphan;	/* unlinked but open inodes */
965 
966 	/*
967 	 * i_disksize keeps track of what the inode size is ON DISK, not
968 	 * in memory.  During truncate, i_size is set to the new size by
969 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
970 	 * set i_disksize to 0 until the truncate is actually under way.
971 	 *
972 	 * The intent is that i_disksize always represents the blocks which
973 	 * are used by this file.  This allows recovery to restart truncate
974 	 * on orphans if we crash during truncate.  We actually write i_disksize
975 	 * into the on-disk inode when writing inodes out, instead of i_size.
976 	 *
977 	 * The only time when i_disksize and i_size may be different is when
978 	 * a truncate is in progress.  The only things which change i_disksize
979 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
980 	 */
981 	loff_t	i_disksize;
982 
983 	/*
984 	 * i_data_sem is for serialising ext4_truncate() against
985 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
986 	 * data tree are chopped off during truncate. We can't do that in
987 	 * ext4 because whenever we perform intermediate commits during
988 	 * truncate, the inode and all the metadata blocks *must* be in a
989 	 * consistent state which allows truncation of the orphans to restart
990 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
991 	 * by other means, so we have i_data_sem.
992 	 */
993 	struct rw_semaphore i_data_sem;
994 	/*
995 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
996 	 * operations. We have to make sure that new page cannot be faulted in
997 	 * a section of the inode that is being punched. We cannot easily use
998 	 * i_data_sem for this since we need protection for the whole punch
999 	 * operation and i_data_sem ranks below transaction start so we have
1000 	 * to occasionally drop it.
1001 	 */
1002 	struct rw_semaphore i_mmap_sem;
1003 	struct inode vfs_inode;
1004 	struct jbd2_inode *jinode;
1005 
1006 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
1007 
1008 	/*
1009 	 * File creation time. Its function is same as that of
1010 	 * struct timespec i_{a,c,m}time in the generic inode.
1011 	 */
1012 	struct timespec i_crtime;
1013 
1014 	/* mballoc */
1015 	struct list_head i_prealloc_list;
1016 	spinlock_t i_prealloc_lock;
1017 
1018 	/* extents status tree */
1019 	struct ext4_es_tree i_es_tree;
1020 	rwlock_t i_es_lock;
1021 	struct list_head i_es_list;
1022 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1023 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1024 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1025 					   extents to shrink. Protected by
1026 					   i_es_lock  */
1027 
1028 	/* ialloc */
1029 	ext4_group_t	i_last_alloc_group;
1030 
1031 	/* allocation reservation info for delalloc */
1032 	/* In case of bigalloc, these refer to clusters rather than blocks */
1033 	unsigned int i_reserved_data_blocks;
1034 	unsigned int i_reserved_meta_blocks;
1035 	unsigned int i_allocated_meta_blocks;
1036 	ext4_lblk_t i_da_metadata_calc_last_lblock;
1037 	int i_da_metadata_calc_len;
1038 
1039 	/* on-disk additional length */
1040 	__u16 i_extra_isize;
1041 
1042 	/* Indicate the inline data space. */
1043 	u16 i_inline_off;
1044 	u16 i_inline_size;
1045 
1046 #ifdef CONFIG_QUOTA
1047 	/* quota space reservation, managed internally by quota code */
1048 	qsize_t i_reserved_quota;
1049 #endif
1050 
1051 	/* Lock protecting lists below */
1052 	spinlock_t i_completed_io_lock;
1053 	/*
1054 	 * Completed IOs that need unwritten extents handling and have
1055 	 * transaction reserved
1056 	 */
1057 	struct list_head i_rsv_conversion_list;
1058 	struct work_struct i_rsv_conversion_work;
1059 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1060 
1061 	spinlock_t i_block_reservation_lock;
1062 
1063 	/*
1064 	 * Transactions that contain inode's metadata needed to complete
1065 	 * fsync and fdatasync, respectively.
1066 	 */
1067 	tid_t i_sync_tid;
1068 	tid_t i_datasync_tid;
1069 
1070 #ifdef CONFIG_QUOTA
1071 	struct dquot *i_dquot[MAXQUOTAS];
1072 #endif
1073 
1074 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1075 	__u32 i_csum_seed;
1076 
1077 	kprojid_t i_projid;
1078 };
1079 
1080 /*
1081  * File system states
1082  */
1083 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1084 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1085 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1086 
1087 /*
1088  * Misc. filesystem flags
1089  */
1090 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1091 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1092 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1093 
1094 /*
1095  * Mount flags set via mount options or defaults
1096  */
1097 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1098 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1099 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1100 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1101 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1102 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1103 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1104 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1105 #ifdef CONFIG_FS_DAX
1106 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
1107 #else
1108 #define EXT4_MOUNT_DAX			0
1109 #endif
1110 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1111 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1112 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1113 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1114 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1115 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1116 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1117 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1118 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1119 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1120 #define EXT4_MOUNT_QUOTA		0x80000 /* Some quota option set */
1121 #define EXT4_MOUNT_USRQUOTA		0x100000 /* "old" user quota */
1122 #define EXT4_MOUNT_GRPQUOTA		0x200000 /* "old" group quota */
1123 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1124 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1125 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1126 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1127 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1128 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1129 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1130 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1131 
1132 /*
1133  * Mount flags set either automatically (could not be set by mount option)
1134  * based on per file system feature or property or in special cases such as
1135  * distinguishing between explicit mount option definition and default.
1136  */
1137 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1138 						      specified delalloc */
1139 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1140 						      size of blocksize * 8
1141 						      blocks */
1142 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1143 						      file systems */
1144 
1145 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1146 						specified journal checksum */
1147 
1148 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1149 						~EXT4_MOUNT_##opt
1150 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1151 						EXT4_MOUNT_##opt
1152 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1153 					 EXT4_MOUNT_##opt)
1154 
1155 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1156 						~EXT4_MOUNT2_##opt
1157 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1158 						EXT4_MOUNT2_##opt
1159 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1160 					 EXT4_MOUNT2_##opt)
1161 
1162 #define ext4_test_and_set_bit		__test_and_set_bit_le
1163 #define ext4_set_bit			__set_bit_le
1164 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1165 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1166 #define ext4_clear_bit			__clear_bit_le
1167 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1168 #define ext4_test_bit			test_bit_le
1169 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1170 #define ext4_find_next_bit		find_next_bit_le
1171 
1172 extern void ext4_set_bits(void *bm, int cur, int len);
1173 
1174 /*
1175  * Maximal mount counts between two filesystem checks
1176  */
1177 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1178 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1179 
1180 /*
1181  * Behaviour when detecting errors
1182  */
1183 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1184 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1185 #define EXT4_ERRORS_PANIC		3	/* Panic */
1186 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1187 
1188 /* Metadata checksum algorithm codes */
1189 #define EXT4_CRC32C_CHKSUM		1
1190 
1191 /*
1192  * Structure of the super block
1193  */
1194 struct ext4_super_block {
1195 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1196 	__le32	s_blocks_count_lo;	/* Blocks count */
1197 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1198 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1199 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1200 	__le32	s_first_data_block;	/* First Data Block */
1201 	__le32	s_log_block_size;	/* Block size */
1202 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1203 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1204 	__le32	s_clusters_per_group;	/* # Clusters per group */
1205 	__le32	s_inodes_per_group;	/* # Inodes per group */
1206 	__le32	s_mtime;		/* Mount time */
1207 /*30*/	__le32	s_wtime;		/* Write time */
1208 	__le16	s_mnt_count;		/* Mount count */
1209 	__le16	s_max_mnt_count;	/* Maximal mount count */
1210 	__le16	s_magic;		/* Magic signature */
1211 	__le16	s_state;		/* File system state */
1212 	__le16	s_errors;		/* Behaviour when detecting errors */
1213 	__le16	s_minor_rev_level;	/* minor revision level */
1214 /*40*/	__le32	s_lastcheck;		/* time of last check */
1215 	__le32	s_checkinterval;	/* max. time between checks */
1216 	__le32	s_creator_os;		/* OS */
1217 	__le32	s_rev_level;		/* Revision level */
1218 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1219 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1220 	/*
1221 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1222 	 *
1223 	 * Note: the difference between the compatible feature set and
1224 	 * the incompatible feature set is that if there is a bit set
1225 	 * in the incompatible feature set that the kernel doesn't
1226 	 * know about, it should refuse to mount the filesystem.
1227 	 *
1228 	 * e2fsck's requirements are more strict; if it doesn't know
1229 	 * about a feature in either the compatible or incompatible
1230 	 * feature set, it must abort and not try to meddle with
1231 	 * things it doesn't understand...
1232 	 */
1233 	__le32	s_first_ino;		/* First non-reserved inode */
1234 	__le16  s_inode_size;		/* size of inode structure */
1235 	__le16	s_block_group_nr;	/* block group # of this superblock */
1236 	__le32	s_feature_compat;	/* compatible feature set */
1237 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1238 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1239 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1240 /*78*/	char	s_volume_name[16];	/* volume name */
1241 /*88*/	char	s_last_mounted[64];	/* directory where last mounted */
1242 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1243 	/*
1244 	 * Performance hints.  Directory preallocation should only
1245 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1246 	 */
1247 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1248 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1249 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1250 	/*
1251 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1252 	 */
1253 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1254 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1255 	__le32	s_journal_dev;		/* device number of journal file */
1256 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1257 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1258 	__u8	s_def_hash_version;	/* Default hash version to use */
1259 	__u8	s_jnl_backup_type;
1260 	__le16  s_desc_size;		/* size of group descriptor */
1261 /*100*/	__le32	s_default_mount_opts;
1262 	__le32	s_first_meta_bg;	/* First metablock block group */
1263 	__le32	s_mkfs_time;		/* When the filesystem was created */
1264 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1265 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1266 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1267 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1268 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1269 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1270 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1271 	__le32	s_flags;		/* Miscellaneous flags */
1272 	__le16  s_raid_stride;		/* RAID stride */
1273 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1274 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1275 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1276 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1277 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1278 	__u8	s_encryption_level;	/* versioning level for encryption */
1279 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1280 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1281 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1282 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1283 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1284 					      snapshot's future use */
1285 	__le32	s_snapshot_list;	/* inode number of the head of the
1286 					   on-disk snapshot list */
1287 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1288 	__le32	s_error_count;		/* number of fs errors */
1289 	__le32	s_first_error_time;	/* first time an error happened */
1290 	__le32	s_first_error_ino;	/* inode involved in first error */
1291 	__le64	s_first_error_block;	/* block involved of first error */
1292 	__u8	s_first_error_func[32];	/* function where the error happened */
1293 	__le32	s_first_error_line;	/* line number where error happened */
1294 	__le32	s_last_error_time;	/* most recent time of an error */
1295 	__le32	s_last_error_ino;	/* inode involved in last error */
1296 	__le32	s_last_error_line;	/* line number where error happened */
1297 	__le64	s_last_error_block;	/* block involved of last error */
1298 	__u8	s_last_error_func[32];	/* function where the error happened */
1299 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1300 	__u8	s_mount_opts[64];
1301 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1302 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1303 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1304 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1305 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1306 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1307 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1308 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1309 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1310 	__le32	s_reserved[98];		/* Padding to the end of the block */
1311 	__le32	s_checksum;		/* crc32c(superblock) */
1312 };
1313 
1314 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1315 
1316 #ifdef __KERNEL__
1317 
1318 /*
1319  * run-time mount flags
1320  */
1321 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1322 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1323 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1324 
1325 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1326 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1327 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1328 #else
1329 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1330 #endif
1331 
1332 /* Number of quota types we support */
1333 #define EXT4_MAXQUOTAS 3
1334 
1335 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1336 #define EXT4_KEY_DESC_PREFIX "ext4:"
1337 #define EXT4_KEY_DESC_PREFIX_SIZE 5
1338 #endif
1339 
1340 /*
1341  * fourth extended-fs super-block data in memory
1342  */
1343 struct ext4_sb_info {
1344 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1345 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1346 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1347 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1348 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1349 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1350 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1351 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1352 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1353 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1354 	unsigned long s_overhead;  /* # of fs overhead clusters */
1355 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1356 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1357 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1358 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1359 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1360 	struct buffer_head **s_group_desc;
1361 	unsigned int s_mount_opt;
1362 	unsigned int s_mount_opt2;
1363 	unsigned int s_mount_flags;
1364 	unsigned int s_def_mount_opt;
1365 	ext4_fsblk_t s_sb_block;
1366 	atomic64_t s_resv_clusters;
1367 	kuid_t s_resuid;
1368 	kgid_t s_resgid;
1369 	unsigned short s_mount_state;
1370 	unsigned short s_pad;
1371 	int s_addr_per_block_bits;
1372 	int s_desc_per_block_bits;
1373 	int s_inode_size;
1374 	int s_first_ino;
1375 	unsigned int s_inode_readahead_blks;
1376 	unsigned int s_inode_goal;
1377 	spinlock_t s_next_gen_lock;
1378 	u32 s_next_generation;
1379 	u32 s_hash_seed[4];
1380 	int s_def_hash_version;
1381 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1382 	struct percpu_counter s_freeclusters_counter;
1383 	struct percpu_counter s_freeinodes_counter;
1384 	struct percpu_counter s_dirs_counter;
1385 	struct percpu_counter s_dirtyclusters_counter;
1386 	struct blockgroup_lock *s_blockgroup_lock;
1387 	struct proc_dir_entry *s_proc;
1388 	struct kobject s_kobj;
1389 	struct completion s_kobj_unregister;
1390 	struct super_block *s_sb;
1391 
1392 	/* Journaling */
1393 	struct journal_s *s_journal;
1394 	struct list_head s_orphan;
1395 	struct mutex s_orphan_lock;
1396 	unsigned long s_resize_flags;		/* Flags indicating if there
1397 						   is a resizer */
1398 	unsigned long s_commit_interval;
1399 	u32 s_max_batch_time;
1400 	u32 s_min_batch_time;
1401 	struct block_device *journal_bdev;
1402 #ifdef CONFIG_QUOTA
1403 	char *s_qf_names[EXT4_MAXQUOTAS];	/* Names of quota files with journalled quota */
1404 	int s_jquota_fmt;			/* Format of quota to use */
1405 #endif
1406 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1407 	struct rb_root system_blks;
1408 
1409 #ifdef EXTENTS_STATS
1410 	/* ext4 extents stats */
1411 	unsigned long s_ext_min;
1412 	unsigned long s_ext_max;
1413 	unsigned long s_depth_max;
1414 	spinlock_t s_ext_stats_lock;
1415 	unsigned long s_ext_blocks;
1416 	unsigned long s_ext_extents;
1417 #endif
1418 
1419 	/* for buddy allocator */
1420 	struct ext4_group_info ***s_group_info;
1421 	struct inode *s_buddy_cache;
1422 	spinlock_t s_md_lock;
1423 	unsigned short *s_mb_offsets;
1424 	unsigned int *s_mb_maxs;
1425 	unsigned int s_group_info_size;
1426 	unsigned int s_mb_free_pending;
1427 
1428 	/* tunables */
1429 	unsigned long s_stripe;
1430 	unsigned int s_mb_stream_request;
1431 	unsigned int s_mb_max_to_scan;
1432 	unsigned int s_mb_min_to_scan;
1433 	unsigned int s_mb_stats;
1434 	unsigned int s_mb_order2_reqs;
1435 	unsigned int s_mb_group_prealloc;
1436 	unsigned int s_max_dir_size_kb;
1437 	/* where last allocation was done - for stream allocation */
1438 	unsigned long s_mb_last_group;
1439 	unsigned long s_mb_last_start;
1440 
1441 	/* stats for buddy allocator */
1442 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1443 	atomic_t s_bal_success;	/* we found long enough chunks */
1444 	atomic_t s_bal_allocated;	/* in blocks */
1445 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1446 	atomic_t s_bal_goals;	/* goal hits */
1447 	atomic_t s_bal_breaks;	/* too long searches */
1448 	atomic_t s_bal_2orders;	/* 2^order hits */
1449 	spinlock_t s_bal_lock;
1450 	unsigned long s_mb_buddies_generated;
1451 	unsigned long long s_mb_generation_time;
1452 	atomic_t s_mb_lost_chunks;
1453 	atomic_t s_mb_preallocated;
1454 	atomic_t s_mb_discarded;
1455 	atomic_t s_lock_busy;
1456 
1457 	/* locality groups */
1458 	struct ext4_locality_group __percpu *s_locality_groups;
1459 
1460 	/* for write statistics */
1461 	unsigned long s_sectors_written_start;
1462 	u64 s_kbytes_written;
1463 
1464 	/* the size of zero-out chunk */
1465 	unsigned int s_extent_max_zeroout_kb;
1466 
1467 	unsigned int s_log_groups_per_flex;
1468 	struct flex_groups *s_flex_groups;
1469 	ext4_group_t s_flex_groups_allocated;
1470 
1471 	/* workqueue for reserved extent conversions (buffered io) */
1472 	struct workqueue_struct *rsv_conversion_wq;
1473 
1474 	/* timer for periodic error stats printing */
1475 	struct timer_list s_err_report;
1476 
1477 	/* Lazy inode table initialization info */
1478 	struct ext4_li_request *s_li_request;
1479 	/* Wait multiplier for lazy initialization thread */
1480 	unsigned int s_li_wait_mult;
1481 
1482 	/* Kernel thread for multiple mount protection */
1483 	struct task_struct *s_mmp_tsk;
1484 
1485 	/* record the last minlen when FITRIM is called. */
1486 	atomic_t s_last_trim_minblks;
1487 
1488 	/* Reference to checksum algorithm driver via cryptoapi */
1489 	struct crypto_shash *s_chksum_driver;
1490 
1491 	/* Precomputed FS UUID checksum for seeding other checksums */
1492 	__u32 s_csum_seed;
1493 
1494 	/* Reclaim extents from extent status tree */
1495 	struct shrinker s_es_shrinker;
1496 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1497 	long s_es_nr_inode;
1498 	struct ext4_es_stats s_es_stats;
1499 	struct mb_cache *s_mb_cache;
1500 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1501 
1502 	/* Ratelimit ext4 messages. */
1503 	struct ratelimit_state s_err_ratelimit_state;
1504 	struct ratelimit_state s_warning_ratelimit_state;
1505 	struct ratelimit_state s_msg_ratelimit_state;
1506 
1507 	/* Barrier between changing inodes' journal flags and writepages ops. */
1508 	struct percpu_rw_semaphore s_journal_flag_rwsem;
1509 
1510 	/* Encryption support */
1511 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1512 	u8 key_prefix[EXT4_KEY_DESC_PREFIX_SIZE];
1513 	u8 key_prefix_size;
1514 #endif
1515 };
1516 
1517 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1518 {
1519 	return sb->s_fs_info;
1520 }
1521 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1522 {
1523 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1524 }
1525 
1526 static inline struct timespec ext4_current_time(struct inode *inode)
1527 {
1528 	return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1529 		current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1530 }
1531 
1532 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1533 {
1534 	return ino == EXT4_ROOT_INO ||
1535 		ino == EXT4_USR_QUOTA_INO ||
1536 		ino == EXT4_GRP_QUOTA_INO ||
1537 		ino == EXT4_BOOT_LOADER_INO ||
1538 		ino == EXT4_JOURNAL_INO ||
1539 		ino == EXT4_RESIZE_INO ||
1540 		(ino >= EXT4_FIRST_INO(sb) &&
1541 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1542 }
1543 
1544 /*
1545  * Inode dynamic state flags
1546  */
1547 enum {
1548 	EXT4_STATE_JDATA,		/* journaled data exists */
1549 	EXT4_STATE_NEW,			/* inode is newly created */
1550 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1551 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1552 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1553 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1554 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1555 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1556 	EXT4_STATE_DIOREAD_LOCK,	/* Disable support for dio read
1557 					   nolocking */
1558 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1559 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1560 };
1561 
1562 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1563 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1564 {									\
1565 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1566 }									\
1567 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1568 {									\
1569 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1570 }									\
1571 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1572 {									\
1573 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1574 }
1575 
1576 /* Add these declarations here only so that these functions can be
1577  * found by name.  Otherwise, they are very hard to locate. */
1578 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1579 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1580 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1581 EXT4_INODE_BIT_FNS(flag, flags, 0)
1582 
1583 /* Add these declarations here only so that these functions can be
1584  * found by name.  Otherwise, they are very hard to locate. */
1585 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1586 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1587 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1588 #if (BITS_PER_LONG < 64)
1589 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1590 
1591 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1592 {
1593 	(ei)->i_state_flags = 0;
1594 }
1595 #else
1596 EXT4_INODE_BIT_FNS(state, flags, 32)
1597 
1598 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1599 {
1600 	/* We depend on the fact that callers will set i_flags */
1601 }
1602 #endif
1603 #else
1604 /* Assume that user mode programs are passing in an ext4fs superblock, not
1605  * a kernel struct super_block.  This will allow us to call the feature-test
1606  * macros from user land. */
1607 #define EXT4_SB(sb)	(sb)
1608 #endif
1609 
1610 /*
1611  * Returns true if the inode is inode is encrypted
1612  */
1613 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1614 
1615 /*
1616  * Codes for operating systems
1617  */
1618 #define EXT4_OS_LINUX		0
1619 #define EXT4_OS_HURD		1
1620 #define EXT4_OS_MASIX		2
1621 #define EXT4_OS_FREEBSD		3
1622 #define EXT4_OS_LITES		4
1623 
1624 /*
1625  * Revision levels
1626  */
1627 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1628 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1629 
1630 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1631 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1632 
1633 #define EXT4_GOOD_OLD_INODE_SIZE 128
1634 
1635 /*
1636  * Feature set definitions
1637  */
1638 
1639 /* Use the ext4_{has,set,clear}_feature_* helpers; these will be removed */
1640 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)			\
1641 	((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1642 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)			\
1643 	((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1644 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)			\
1645 	((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1646 #define EXT4_SET_COMPAT_FEATURE(sb,mask)			\
1647 	EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1648 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)			\
1649 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1650 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)			\
1651 	EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1652 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)			\
1653 	EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1654 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
1655 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1656 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
1657 	EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1658 
1659 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1660 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1661 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1662 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1663 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1664 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1665 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1666 
1667 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1668 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1669 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1670 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1671 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1672 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1673 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1674 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1675 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1676 /*
1677  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1678  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1679  * all other data structures' checksums.  However, the METADATA_CSUM and
1680  * GDT_CSUM bits are mutually exclusive.
1681  */
1682 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1683 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1684 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1685 
1686 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1687 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1688 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1689 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1690 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1691 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1692 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1693 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1694 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1695 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1696 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1697 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1698 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1699 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1700 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1701 
1702 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1703 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1704 { \
1705 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1706 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1707 } \
1708 static inline void ext4_set_feature_##name(struct super_block *sb) \
1709 { \
1710 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1711 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1712 } \
1713 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1714 { \
1715 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1716 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1717 }
1718 
1719 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1720 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1721 { \
1722 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1723 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1724 } \
1725 static inline void ext4_set_feature_##name(struct super_block *sb) \
1726 { \
1727 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1728 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1729 } \
1730 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1731 { \
1732 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1733 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1734 }
1735 
1736 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1737 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1738 { \
1739 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1740 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1741 } \
1742 static inline void ext4_set_feature_##name(struct super_block *sb) \
1743 { \
1744 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
1745 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1746 } \
1747 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1748 { \
1749 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1750 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1751 }
1752 
1753 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1754 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1755 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1756 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1757 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1758 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1759 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1760 
1761 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1762 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1763 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1764 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1765 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1766 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1767 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1768 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1769 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1770 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1771 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1772 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1773 
1774 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1775 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
1776 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
1777 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
1778 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
1779 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
1780 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
1781 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
1782 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
1783 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
1784 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
1785 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
1786 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
1787 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
1788 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
1789 
1790 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1791 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1792 					 EXT4_FEATURE_INCOMPAT_META_BG)
1793 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1794 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1795 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1796 
1797 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1798 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1799 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1800 					 EXT4_FEATURE_INCOMPAT_META_BG)
1801 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1802 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1803 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1804 
1805 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1806 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1807 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1808 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1809 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1810 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1811 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1812 					 EXT4_FEATURE_INCOMPAT_MMP | \
1813 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1814 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1815 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED)
1816 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1817 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1818 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1819 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1820 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1821 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1822 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1823 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1824 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1825 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
1826 					 EXT4_FEATURE_RO_COMPAT_PROJECT)
1827 
1828 #define EXTN_FEATURE_FUNCS(ver) \
1829 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1830 { \
1831 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1832 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1833 } \
1834 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1835 { \
1836 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1837 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1838 } \
1839 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1840 { \
1841 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1842 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1843 }
1844 
1845 EXTN_FEATURE_FUNCS(2)
1846 EXTN_FEATURE_FUNCS(3)
1847 EXTN_FEATURE_FUNCS(4)
1848 
1849 static inline bool ext4_has_compat_features(struct super_block *sb)
1850 {
1851 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1852 }
1853 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1854 {
1855 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1856 }
1857 static inline bool ext4_has_incompat_features(struct super_block *sb)
1858 {
1859 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
1860 }
1861 
1862 /*
1863  * Default values for user and/or group using reserved blocks
1864  */
1865 #define	EXT4_DEF_RESUID		0
1866 #define	EXT4_DEF_RESGID		0
1867 
1868 /*
1869  * Default project ID
1870  */
1871 #define	EXT4_DEF_PROJID		0
1872 
1873 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1874 
1875 /*
1876  * Default mount options
1877  */
1878 #define EXT4_DEFM_DEBUG		0x0001
1879 #define EXT4_DEFM_BSDGROUPS	0x0002
1880 #define EXT4_DEFM_XATTR_USER	0x0004
1881 #define EXT4_DEFM_ACL		0x0008
1882 #define EXT4_DEFM_UID16		0x0010
1883 #define EXT4_DEFM_JMODE		0x0060
1884 #define EXT4_DEFM_JMODE_DATA	0x0020
1885 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1886 #define EXT4_DEFM_JMODE_WBACK	0x0060
1887 #define EXT4_DEFM_NOBARRIER	0x0100
1888 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1889 #define EXT4_DEFM_DISCARD	0x0400
1890 #define EXT4_DEFM_NODELALLOC	0x0800
1891 
1892 /*
1893  * Default journal batch times
1894  */
1895 #define EXT4_DEF_MIN_BATCH_TIME	0
1896 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1897 
1898 /*
1899  * Minimum number of groups in a flexgroup before we separate out
1900  * directories into the first block group of a flexgroup
1901  */
1902 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1903 
1904 /*
1905  * Structure of a directory entry
1906  */
1907 #define EXT4_NAME_LEN 255
1908 
1909 struct ext4_dir_entry {
1910 	__le32	inode;			/* Inode number */
1911 	__le16	rec_len;		/* Directory entry length */
1912 	__le16	name_len;		/* Name length */
1913 	char	name[EXT4_NAME_LEN];	/* File name */
1914 };
1915 
1916 /*
1917  * The new version of the directory entry.  Since EXT4 structures are
1918  * stored in intel byte order, and the name_len field could never be
1919  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1920  * file_type field.
1921  */
1922 struct ext4_dir_entry_2 {
1923 	__le32	inode;			/* Inode number */
1924 	__le16	rec_len;		/* Directory entry length */
1925 	__u8	name_len;		/* Name length */
1926 	__u8	file_type;
1927 	char	name[EXT4_NAME_LEN];	/* File name */
1928 };
1929 
1930 /*
1931  * This is a bogus directory entry at the end of each leaf block that
1932  * records checksums.
1933  */
1934 struct ext4_dir_entry_tail {
1935 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1936 	__le16	det_rec_len;		/* 12 */
1937 	__u8	det_reserved_zero2;	/* Zero name length */
1938 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1939 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1940 };
1941 
1942 #define EXT4_DIRENT_TAIL(block, blocksize) \
1943 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1944 					((blocksize) - \
1945 					 sizeof(struct ext4_dir_entry_tail))))
1946 
1947 /*
1948  * Ext4 directory file types.  Only the low 3 bits are used.  The
1949  * other bits are reserved for now.
1950  */
1951 #define EXT4_FT_UNKNOWN		0
1952 #define EXT4_FT_REG_FILE	1
1953 #define EXT4_FT_DIR		2
1954 #define EXT4_FT_CHRDEV		3
1955 #define EXT4_FT_BLKDEV		4
1956 #define EXT4_FT_FIFO		5
1957 #define EXT4_FT_SOCK		6
1958 #define EXT4_FT_SYMLINK		7
1959 
1960 #define EXT4_FT_MAX		8
1961 
1962 #define EXT4_FT_DIR_CSUM	0xDE
1963 
1964 /*
1965  * EXT4_DIR_PAD defines the directory entries boundaries
1966  *
1967  * NOTE: It must be a multiple of 4
1968  */
1969 #define EXT4_DIR_PAD			4
1970 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1971 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1972 					 ~EXT4_DIR_ROUND)
1973 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1974 
1975 /*
1976  * If we ever get support for fs block sizes > page_size, we'll need
1977  * to remove the #if statements in the next two functions...
1978  */
1979 static inline unsigned int
1980 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1981 {
1982 	unsigned len = le16_to_cpu(dlen);
1983 
1984 #if (PAGE_SIZE >= 65536)
1985 	if (len == EXT4_MAX_REC_LEN || len == 0)
1986 		return blocksize;
1987 	return (len & 65532) | ((len & 3) << 16);
1988 #else
1989 	return len;
1990 #endif
1991 }
1992 
1993 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1994 {
1995 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1996 		BUG();
1997 #if (PAGE_SIZE >= 65536)
1998 	if (len < 65536)
1999 		return cpu_to_le16(len);
2000 	if (len == blocksize) {
2001 		if (blocksize == 65536)
2002 			return cpu_to_le16(EXT4_MAX_REC_LEN);
2003 		else
2004 			return cpu_to_le16(0);
2005 	}
2006 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2007 #else
2008 	return cpu_to_le16(len);
2009 #endif
2010 }
2011 
2012 /*
2013  * Hash Tree Directory indexing
2014  * (c) Daniel Phillips, 2001
2015  */
2016 
2017 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2018 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2019 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
2020 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2021 
2022 /* Legal values for the dx_root hash_version field: */
2023 
2024 #define DX_HASH_LEGACY		0
2025 #define DX_HASH_HALF_MD4	1
2026 #define DX_HASH_TEA		2
2027 #define DX_HASH_LEGACY_UNSIGNED	3
2028 #define DX_HASH_HALF_MD4_UNSIGNED	4
2029 #define DX_HASH_TEA_UNSIGNED		5
2030 
2031 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2032 			      const void *address, unsigned int length)
2033 {
2034 	struct {
2035 		struct shash_desc shash;
2036 		char ctx[4];
2037 	} desc;
2038 	int err;
2039 
2040 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2041 
2042 	desc.shash.tfm = sbi->s_chksum_driver;
2043 	desc.shash.flags = 0;
2044 	*(u32 *)desc.ctx = crc;
2045 
2046 	err = crypto_shash_update(&desc.shash, address, length);
2047 	BUG_ON(err);
2048 
2049 	return *(u32 *)desc.ctx;
2050 }
2051 
2052 #ifdef __KERNEL__
2053 
2054 /* hash info structure used by the directory hash */
2055 struct dx_hash_info
2056 {
2057 	u32		hash;
2058 	u32		minor_hash;
2059 	int		hash_version;
2060 	u32		*seed;
2061 };
2062 
2063 
2064 /* 32 and 64 bit signed EOF for dx directories */
2065 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2066 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2067 
2068 
2069 /*
2070  * Control parameters used by ext4_htree_next_block
2071  */
2072 #define HASH_NB_ALWAYS		1
2073 
2074 struct ext4_filename {
2075 	const struct qstr *usr_fname;
2076 	struct fscrypt_str disk_name;
2077 	struct dx_hash_info hinfo;
2078 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2079 	struct fscrypt_str crypto_buf;
2080 #endif
2081 };
2082 
2083 #define fname_name(p) ((p)->disk_name.name)
2084 #define fname_len(p)  ((p)->disk_name.len)
2085 
2086 /*
2087  * Describe an inode's exact location on disk and in memory
2088  */
2089 struct ext4_iloc
2090 {
2091 	struct buffer_head *bh;
2092 	unsigned long offset;
2093 	ext4_group_t block_group;
2094 };
2095 
2096 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2097 {
2098 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2099 }
2100 
2101 /*
2102  * This structure is stuffed into the struct file's private_data field
2103  * for directories.  It is where we put information so that we can do
2104  * readdir operations in hash tree order.
2105  */
2106 struct dir_private_info {
2107 	struct rb_root	root;
2108 	struct rb_node	*curr_node;
2109 	struct fname	*extra_fname;
2110 	loff_t		last_pos;
2111 	__u32		curr_hash;
2112 	__u32		curr_minor_hash;
2113 	__u32		next_hash;
2114 };
2115 
2116 /* calculate the first block number of the group */
2117 static inline ext4_fsblk_t
2118 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2119 {
2120 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2121 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2122 }
2123 
2124 /*
2125  * Special error return code only used by dx_probe() and its callers.
2126  */
2127 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2128 
2129 /*
2130  * Timeout and state flag for lazy initialization inode thread.
2131  */
2132 #define EXT4_DEF_LI_WAIT_MULT			10
2133 #define EXT4_DEF_LI_MAX_START_DELAY		5
2134 #define EXT4_LAZYINIT_QUIT			0x0001
2135 #define EXT4_LAZYINIT_RUNNING			0x0002
2136 
2137 /*
2138  * Lazy inode table initialization info
2139  */
2140 struct ext4_lazy_init {
2141 	unsigned long		li_state;
2142 	struct list_head	li_request_list;
2143 	struct mutex		li_list_mtx;
2144 };
2145 
2146 struct ext4_li_request {
2147 	struct super_block	*lr_super;
2148 	struct ext4_sb_info	*lr_sbi;
2149 	ext4_group_t		lr_next_group;
2150 	struct list_head	lr_request;
2151 	unsigned long		lr_next_sched;
2152 	unsigned long		lr_timeout;
2153 };
2154 
2155 struct ext4_features {
2156 	struct kobject f_kobj;
2157 	struct completion f_kobj_unregister;
2158 };
2159 
2160 /*
2161  * This structure will be used for multiple mount protection. It will be
2162  * written into the block number saved in the s_mmp_block field in the
2163  * superblock. Programs that check MMP should assume that if
2164  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2165  * to use the filesystem, regardless of how old the timestamp is.
2166  */
2167 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2168 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2169 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2170 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2171 
2172 struct mmp_struct {
2173 	__le32	mmp_magic;		/* Magic number for MMP */
2174 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2175 
2176 	/*
2177 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2178 	 * purposes and do not affect the correctness of the algorithm
2179 	 */
2180 	__le64	mmp_time;		/* Time last updated */
2181 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2182 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2183 
2184 	/*
2185 	 * mmp_check_interval is used to verify if the MMP block has been
2186 	 * updated on the block device. The value is updated based on the
2187 	 * maximum time to write the MMP block during an update cycle.
2188 	 */
2189 	__le16	mmp_check_interval;
2190 
2191 	__le16	mmp_pad1;
2192 	__le32	mmp_pad2[226];
2193 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2194 };
2195 
2196 /* arguments passed to the mmp thread */
2197 struct mmpd_data {
2198 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2199 	struct super_block *sb;  /* super block of the fs */
2200 };
2201 
2202 /*
2203  * Check interval multiplier
2204  * The MMP block is written every update interval and initially checked every
2205  * update interval x the multiplier (the value is then adapted based on the
2206  * write latency). The reason is that writes can be delayed under load and we
2207  * don't want readers to incorrectly assume that the filesystem is no longer
2208  * in use.
2209  */
2210 #define EXT4_MMP_CHECK_MULT		2UL
2211 
2212 /*
2213  * Minimum interval for MMP checking in seconds.
2214  */
2215 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2216 
2217 /*
2218  * Maximum interval for MMP checking in seconds.
2219  */
2220 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2221 
2222 /*
2223  * Function prototypes
2224  */
2225 
2226 /*
2227  * Ok, these declarations are also in <linux/kernel.h> but none of the
2228  * ext4 source programs needs to include it so they are duplicated here.
2229  */
2230 # define NORET_TYPE	/**/
2231 # define ATTRIB_NORET	__attribute__((noreturn))
2232 # define NORET_AND	noreturn,
2233 
2234 /* bitmap.c */
2235 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2236 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2237 				struct ext4_group_desc *gdp,
2238 				struct buffer_head *bh, int sz);
2239 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2240 				  struct ext4_group_desc *gdp,
2241 				  struct buffer_head *bh, int sz);
2242 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2243 				struct ext4_group_desc *gdp,
2244 				struct buffer_head *bh);
2245 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2246 				  struct ext4_group_desc *gdp,
2247 				  struct buffer_head *bh);
2248 
2249 /* balloc.c */
2250 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2251 					 ext4_fsblk_t blocknr,
2252 					 ext4_group_t *blockgrpp,
2253 					 ext4_grpblk_t *offsetp);
2254 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2255 					  ext4_fsblk_t block);
2256 
2257 extern unsigned int ext4_block_group(struct super_block *sb,
2258 			ext4_fsblk_t blocknr);
2259 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2260 			ext4_fsblk_t blocknr);
2261 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2262 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2263 			ext4_group_t group);
2264 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2265 					 ext4_fsblk_t goal,
2266 					 unsigned int flags,
2267 					 unsigned long *count,
2268 					 int *errp);
2269 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2270 				    s64 nclusters, unsigned int flags);
2271 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2272 extern void ext4_check_blocks_bitmap(struct super_block *);
2273 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2274 						    ext4_group_t block_group,
2275 						    struct buffer_head ** bh);
2276 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2277 
2278 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2279 						ext4_group_t block_group);
2280 extern int ext4_wait_block_bitmap(struct super_block *sb,
2281 				  ext4_group_t block_group,
2282 				  struct buffer_head *bh);
2283 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2284 						  ext4_group_t block_group);
2285 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2286 					      ext4_group_t block_group,
2287 					      struct ext4_group_desc *gdp);
2288 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2289 
2290 static inline int ext4_sb_has_crypto(struct super_block *sb)
2291 {
2292 	return ext4_has_feature_encrypt(sb);
2293 }
2294 
2295 static inline bool ext4_encrypted_inode(struct inode *inode)
2296 {
2297 	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
2298 }
2299 
2300 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2301 static inline int ext4_fname_setup_filename(struct inode *dir,
2302 			const struct qstr *iname,
2303 			int lookup, struct ext4_filename *fname)
2304 {
2305 	struct fscrypt_name name;
2306 	int err;
2307 
2308 	memset(fname, 0, sizeof(struct ext4_filename));
2309 
2310 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2311 
2312 	fname->usr_fname = name.usr_fname;
2313 	fname->disk_name = name.disk_name;
2314 	fname->hinfo.hash = name.hash;
2315 	fname->hinfo.minor_hash = name.minor_hash;
2316 	fname->crypto_buf = name.crypto_buf;
2317 	return err;
2318 }
2319 
2320 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2321 {
2322 	struct fscrypt_name name;
2323 
2324 	name.crypto_buf = fname->crypto_buf;
2325 	fscrypt_free_filename(&name);
2326 
2327 	fname->crypto_buf.name = NULL;
2328 	fname->usr_fname = NULL;
2329 	fname->disk_name.name = NULL;
2330 }
2331 #else
2332 static inline int ext4_fname_setup_filename(struct inode *dir,
2333 		const struct qstr *iname,
2334 		int lookup, struct ext4_filename *fname)
2335 {
2336 	fname->usr_fname = iname;
2337 	fname->disk_name.name = (unsigned char *) iname->name;
2338 	fname->disk_name.len = iname->len;
2339 	return 0;
2340 }
2341 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2342 
2343 #define fscrypt_set_d_op(i)
2344 #define fscrypt_get_ctx			fscrypt_notsupp_get_ctx
2345 #define fscrypt_release_ctx		fscrypt_notsupp_release_ctx
2346 #define fscrypt_encrypt_page		fscrypt_notsupp_encrypt_page
2347 #define fscrypt_decrypt_page		fscrypt_notsupp_decrypt_page
2348 #define fscrypt_decrypt_bio_pages	fscrypt_notsupp_decrypt_bio_pages
2349 #define fscrypt_pullback_bio_page	fscrypt_notsupp_pullback_bio_page
2350 #define fscrypt_restore_control_page	fscrypt_notsupp_restore_control_page
2351 #define fscrypt_zeroout_range		fscrypt_notsupp_zeroout_range
2352 #define fscrypt_process_policy		fscrypt_notsupp_process_policy
2353 #define fscrypt_get_policy		fscrypt_notsupp_get_policy
2354 #define fscrypt_has_permitted_context	fscrypt_notsupp_has_permitted_context
2355 #define fscrypt_inherit_context		fscrypt_notsupp_inherit_context
2356 #define fscrypt_get_encryption_info	fscrypt_notsupp_get_encryption_info
2357 #define fscrypt_put_encryption_info	fscrypt_notsupp_put_encryption_info
2358 #define fscrypt_setup_filename		fscrypt_notsupp_setup_filename
2359 #define fscrypt_free_filename		fscrypt_notsupp_free_filename
2360 #define fscrypt_fname_encrypted_size	fscrypt_notsupp_fname_encrypted_size
2361 #define fscrypt_fname_alloc_buffer	fscrypt_notsupp_fname_alloc_buffer
2362 #define fscrypt_fname_free_buffer	fscrypt_notsupp_fname_free_buffer
2363 #define fscrypt_fname_disk_to_usr	fscrypt_notsupp_fname_disk_to_usr
2364 #define fscrypt_fname_usr_to_disk	fscrypt_notsupp_fname_usr_to_disk
2365 #endif
2366 
2367 /* dir.c */
2368 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2369 				  struct file *,
2370 				  struct ext4_dir_entry_2 *,
2371 				  struct buffer_head *, char *, int,
2372 				  unsigned int);
2373 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2374 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2375 					(de), (bh), (buf), (size), (offset)))
2376 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2377 				__u32 minor_hash,
2378 				struct ext4_dir_entry_2 *dirent,
2379 				struct fscrypt_str *ent_name);
2380 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2381 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2382 			     struct buffer_head *bh,
2383 			     void *buf, int buf_size,
2384 			     struct ext4_filename *fname,
2385 			     struct ext4_dir_entry_2 **dest_de);
2386 int ext4_insert_dentry(struct inode *dir,
2387 		       struct inode *inode,
2388 		       struct ext4_dir_entry_2 *de,
2389 		       int buf_size,
2390 		       struct ext4_filename *fname);
2391 static inline void ext4_update_dx_flag(struct inode *inode)
2392 {
2393 	if (!ext4_has_feature_dir_index(inode->i_sb))
2394 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2395 }
2396 static unsigned char ext4_filetype_table[] = {
2397 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2398 };
2399 
2400 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2401 {
2402 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2403 		return DT_UNKNOWN;
2404 
2405 	return ext4_filetype_table[filetype];
2406 }
2407 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2408 			     void *buf, int buf_size);
2409 
2410 /* fsync.c */
2411 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2412 
2413 /* hash.c */
2414 extern int ext4fs_dirhash(const char *name, int len, struct
2415 			  dx_hash_info *hinfo);
2416 
2417 /* ialloc.c */
2418 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2419 				      const struct qstr *qstr, __u32 goal,
2420 				      uid_t *owner, int handle_type,
2421 				      unsigned int line_no, int nblocks);
2422 
2423 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner) \
2424 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2425 			 0, 0, 0)
2426 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2427 				    type, nblocks)		    \
2428 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2429 			 (type), __LINE__, (nblocks))
2430 
2431 
2432 extern void ext4_free_inode(handle_t *, struct inode *);
2433 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2434 extern unsigned long ext4_count_free_inodes(struct super_block *);
2435 extern unsigned long ext4_count_dirs(struct super_block *);
2436 extern void ext4_check_inodes_bitmap(struct super_block *);
2437 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2438 extern int ext4_init_inode_table(struct super_block *sb,
2439 				 ext4_group_t group, int barrier);
2440 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2441 
2442 /* mballoc.c */
2443 extern const struct file_operations ext4_seq_mb_groups_fops;
2444 extern long ext4_mb_stats;
2445 extern long ext4_mb_max_to_scan;
2446 extern int ext4_mb_init(struct super_block *);
2447 extern int ext4_mb_release(struct super_block *);
2448 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2449 				struct ext4_allocation_request *, int *);
2450 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2451 extern void ext4_discard_preallocations(struct inode *);
2452 extern int __init ext4_init_mballoc(void);
2453 extern void ext4_exit_mballoc(void);
2454 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2455 			     struct buffer_head *bh, ext4_fsblk_t block,
2456 			     unsigned long count, int flags);
2457 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2458 				   ext4_group_t ngroups);
2459 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2460 		ext4_group_t i, struct ext4_group_desc *desc);
2461 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2462 				ext4_fsblk_t block, unsigned long count);
2463 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2464 
2465 /* inode.c */
2466 int ext4_inode_is_fast_symlink(struct inode *inode);
2467 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2468 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2469 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2470 			     struct buffer_head *bh_result, int create);
2471 int ext4_dax_get_block(struct inode *inode, sector_t iblock,
2472 		       struct buffer_head *bh_result, int create);
2473 int ext4_get_block(struct inode *inode, sector_t iblock,
2474 		   struct buffer_head *bh_result, int create);
2475 int ext4_dio_get_block(struct inode *inode, sector_t iblock,
2476 		       struct buffer_head *bh_result, int create);
2477 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2478 			   struct buffer_head *bh, int create);
2479 int ext4_walk_page_buffers(handle_t *handle,
2480 			   struct buffer_head *head,
2481 			   unsigned from,
2482 			   unsigned to,
2483 			   int *partial,
2484 			   int (*fn)(handle_t *handle,
2485 				     struct buffer_head *bh));
2486 int do_journal_get_write_access(handle_t *handle,
2487 				struct buffer_head *bh);
2488 #define FALL_BACK_TO_NONDELALLOC 1
2489 #define CONVERT_INLINE_DATA	 2
2490 
2491 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2492 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
2493 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2494 extern int  ext4_setattr(struct dentry *, struct iattr *);
2495 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2496 				struct kstat *stat);
2497 extern void ext4_evict_inode(struct inode *);
2498 extern void ext4_clear_inode(struct inode *);
2499 extern int  ext4_sync_inode(handle_t *, struct inode *);
2500 extern void ext4_dirty_inode(struct inode *, int);
2501 extern int ext4_change_inode_journal_flag(struct inode *, int);
2502 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2503 extern int ext4_inode_attach_jinode(struct inode *inode);
2504 extern int ext4_can_truncate(struct inode *inode);
2505 extern void ext4_truncate(struct inode *);
2506 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2507 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2508 extern void ext4_set_inode_flags(struct inode *);
2509 extern void ext4_get_inode_flags(struct ext4_inode_info *);
2510 extern int ext4_alloc_da_blocks(struct inode *inode);
2511 extern void ext4_set_aops(struct inode *inode);
2512 extern int ext4_writepage_trans_blocks(struct inode *);
2513 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2514 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2515 			     loff_t lstart, loff_t lend);
2516 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2517 extern int ext4_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf);
2518 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2519 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2520 extern void ext4_da_update_reserve_space(struct inode *inode,
2521 					int used, int quota_claim);
2522 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2523 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2524 extern int ext4_get_next_extent(struct inode *inode, ext4_lblk_t lblk,
2525 				unsigned int map_len,
2526 				struct extent_status *result);
2527 
2528 /* indirect.c */
2529 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2530 				struct ext4_map_blocks *map, int flags);
2531 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2532 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2533 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2534 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2535 				 ext4_lblk_t start, ext4_lblk_t end);
2536 
2537 /* ioctl.c */
2538 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2539 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2540 
2541 /* migrate.c */
2542 extern int ext4_ext_migrate(struct inode *);
2543 extern int ext4_ind_migrate(struct inode *inode);
2544 
2545 /* namei.c */
2546 extern int ext4_dirent_csum_verify(struct inode *inode,
2547 				   struct ext4_dir_entry *dirent);
2548 extern int ext4_orphan_add(handle_t *, struct inode *);
2549 extern int ext4_orphan_del(handle_t *, struct inode *);
2550 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2551 				__u32 start_minor_hash, __u32 *next_hash);
2552 extern int ext4_search_dir(struct buffer_head *bh,
2553 			   char *search_buf,
2554 			   int buf_size,
2555 			   struct inode *dir,
2556 			   struct ext4_filename *fname,
2557 			   const struct qstr *d_name,
2558 			   unsigned int offset,
2559 			   struct ext4_dir_entry_2 **res_dir);
2560 extern int ext4_generic_delete_entry(handle_t *handle,
2561 				     struct inode *dir,
2562 				     struct ext4_dir_entry_2 *de_del,
2563 				     struct buffer_head *bh,
2564 				     void *entry_buf,
2565 				     int buf_size,
2566 				     int csum_size);
2567 extern bool ext4_empty_dir(struct inode *inode);
2568 
2569 /* resize.c */
2570 extern int ext4_group_add(struct super_block *sb,
2571 				struct ext4_new_group_data *input);
2572 extern int ext4_group_extend(struct super_block *sb,
2573 				struct ext4_super_block *es,
2574 				ext4_fsblk_t n_blocks_count);
2575 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2576 
2577 /* super.c */
2578 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2579 extern int ext4_calculate_overhead(struct super_block *sb);
2580 extern void ext4_superblock_csum_set(struct super_block *sb);
2581 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2582 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2583 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2584 				    ext4_group_t ngroup);
2585 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2586 				     char nbuf[16]);
2587 
2588 extern __printf(4, 5)
2589 void __ext4_error(struct super_block *, const char *, unsigned int,
2590 		  const char *, ...);
2591 extern __printf(5, 6)
2592 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2593 		      const char *, ...);
2594 extern __printf(5, 6)
2595 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2596 		     const char *, ...);
2597 extern void __ext4_std_error(struct super_block *, const char *,
2598 			     unsigned int, int);
2599 extern __printf(4, 5)
2600 void __ext4_abort(struct super_block *, const char *, unsigned int,
2601 		  const char *, ...);
2602 extern __printf(4, 5)
2603 void __ext4_warning(struct super_block *, const char *, unsigned int,
2604 		    const char *, ...);
2605 extern __printf(4, 5)
2606 void __ext4_warning_inode(const struct inode *inode, const char *function,
2607 			  unsigned int line, const char *fmt, ...);
2608 extern __printf(3, 4)
2609 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2610 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2611 			   const char *, unsigned int, const char *);
2612 extern __printf(7, 8)
2613 void __ext4_grp_locked_error(const char *, unsigned int,
2614 			     struct super_block *, ext4_group_t,
2615 			     unsigned long, ext4_fsblk_t,
2616 			     const char *, ...);
2617 
2618 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2619 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2620 
2621 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
2622 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2623 
2624 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2625 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2626 
2627 #ifdef CONFIG_PRINTK
2628 
2629 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2630 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2631 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2632 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2633 #define ext4_error(sb, fmt, ...)					\
2634 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2635 #define ext4_abort(sb, fmt, ...)					\
2636 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2637 #define ext4_warning(sb, fmt, ...)					\
2638 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2639 #define ext4_warning_inode(inode, fmt, ...)				\
2640 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2641 #define ext4_msg(sb, level, fmt, ...)				\
2642 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2643 #define dump_mmp_msg(sb, mmp, msg)					\
2644 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2645 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2646 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2647 				fmt, ##__VA_ARGS__)
2648 
2649 #else
2650 
2651 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2652 do {									\
2653 	no_printk(fmt, ##__VA_ARGS__);					\
2654 	__ext4_error_inode(inode, "", 0, block, " ");			\
2655 } while (0)
2656 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2657 do {									\
2658 	no_printk(fmt, ##__VA_ARGS__);					\
2659 	__ext4_error_file(file, "", 0, block, " ");			\
2660 } while (0)
2661 #define ext4_error(sb, fmt, ...)					\
2662 do {									\
2663 	no_printk(fmt, ##__VA_ARGS__);					\
2664 	__ext4_error(sb, "", 0, " ");					\
2665 } while (0)
2666 #define ext4_abort(sb, fmt, ...)					\
2667 do {									\
2668 	no_printk(fmt, ##__VA_ARGS__);					\
2669 	__ext4_abort(sb, "", 0, " ");					\
2670 } while (0)
2671 #define ext4_warning(sb, fmt, ...)					\
2672 do {									\
2673 	no_printk(fmt, ##__VA_ARGS__);					\
2674 	__ext4_warning(sb, "", 0, " ");					\
2675 } while (0)
2676 #define ext4_warning_inode(inode, fmt, ...)				\
2677 do {									\
2678 	no_printk(fmt, ##__VA_ARGS__);					\
2679 	__ext4_warning_inode(inode, "", 0, " ");			\
2680 } while (0)
2681 #define ext4_msg(sb, level, fmt, ...)					\
2682 do {									\
2683 	no_printk(fmt, ##__VA_ARGS__);					\
2684 	__ext4_msg(sb, "", " ");					\
2685 } while (0)
2686 #define dump_mmp_msg(sb, mmp, msg)					\
2687 	__dump_mmp_msg(sb, mmp, "", 0, "")
2688 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2689 do {									\
2690 	no_printk(fmt, ##__VA_ARGS__);				\
2691 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2692 } while (0)
2693 
2694 #endif
2695 
2696 extern void ext4_update_dynamic_rev(struct super_block *sb);
2697 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2698 					__u32 compat);
2699 extern int ext4_update_rocompat_feature(handle_t *handle,
2700 					struct super_block *sb,	__u32 rocompat);
2701 extern int ext4_update_incompat_feature(handle_t *handle,
2702 					struct super_block *sb,	__u32 incompat);
2703 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2704 				      struct ext4_group_desc *bg);
2705 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2706 				      struct ext4_group_desc *bg);
2707 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2708 				     struct ext4_group_desc *bg);
2709 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2710 				      struct ext4_group_desc *bg);
2711 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2712 				 struct ext4_group_desc *bg);
2713 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2714 				struct ext4_group_desc *bg);
2715 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2716 				   struct ext4_group_desc *bg);
2717 extern void ext4_block_bitmap_set(struct super_block *sb,
2718 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2719 extern void ext4_inode_bitmap_set(struct super_block *sb,
2720 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2721 extern void ext4_inode_table_set(struct super_block *sb,
2722 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2723 extern void ext4_free_group_clusters_set(struct super_block *sb,
2724 					 struct ext4_group_desc *bg,
2725 					 __u32 count);
2726 extern void ext4_free_inodes_set(struct super_block *sb,
2727 				struct ext4_group_desc *bg, __u32 count);
2728 extern void ext4_used_dirs_set(struct super_block *sb,
2729 				struct ext4_group_desc *bg, __u32 count);
2730 extern void ext4_itable_unused_set(struct super_block *sb,
2731 				   struct ext4_group_desc *bg, __u32 count);
2732 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2733 				       struct ext4_group_desc *gdp);
2734 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2735 				     struct ext4_group_desc *gdp);
2736 extern int ext4_register_li_request(struct super_block *sb,
2737 				    ext4_group_t first_not_zeroed);
2738 
2739 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2740 {
2741 	return ext4_has_feature_gdt_csum(sb) ||
2742 	       EXT4_SB(sb)->s_chksum_driver != NULL;
2743 }
2744 
2745 static inline int ext4_has_metadata_csum(struct super_block *sb)
2746 {
2747 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2748 		     !EXT4_SB(sb)->s_chksum_driver);
2749 
2750 	return (EXT4_SB(sb)->s_chksum_driver != NULL);
2751 }
2752 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2753 {
2754 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2755 		le32_to_cpu(es->s_blocks_count_lo);
2756 }
2757 
2758 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2759 {
2760 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2761 		le32_to_cpu(es->s_r_blocks_count_lo);
2762 }
2763 
2764 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2765 {
2766 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2767 		le32_to_cpu(es->s_free_blocks_count_lo);
2768 }
2769 
2770 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2771 					 ext4_fsblk_t blk)
2772 {
2773 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2774 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2775 }
2776 
2777 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2778 					      ext4_fsblk_t blk)
2779 {
2780 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2781 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2782 }
2783 
2784 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2785 					   ext4_fsblk_t blk)
2786 {
2787 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2788 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2789 }
2790 
2791 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2792 {
2793 	if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2794 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2795 			le32_to_cpu(raw_inode->i_size_lo);
2796 	else
2797 		return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2798 }
2799 
2800 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2801 {
2802 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2803 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2804 }
2805 
2806 static inline
2807 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2808 					    ext4_group_t group)
2809 {
2810 	 struct ext4_group_info ***grp_info;
2811 	 long indexv, indexh;
2812 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2813 	 grp_info = EXT4_SB(sb)->s_group_info;
2814 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2815 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2816 	 return grp_info[indexv][indexh];
2817 }
2818 
2819 /*
2820  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2821  * the locking protocol documented in the comments of ext4_group_add()
2822  * in resize.c
2823  */
2824 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2825 {
2826 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2827 
2828 	smp_rmb();
2829 	return ngroups;
2830 }
2831 
2832 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2833 					     ext4_group_t block_group)
2834 {
2835 	return block_group >> sbi->s_log_groups_per_flex;
2836 }
2837 
2838 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2839 {
2840 	return 1 << sbi->s_log_groups_per_flex;
2841 }
2842 
2843 #define ext4_std_error(sb, errno)				\
2844 do {								\
2845 	if ((errno))						\
2846 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2847 } while (0)
2848 
2849 #ifdef CONFIG_SMP
2850 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2851  * counters. So we need to make sure we have free clusters more
2852  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2853  */
2854 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2855 #else
2856 #define EXT4_FREECLUSTERS_WATERMARK 0
2857 #endif
2858 
2859 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
2860 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2861 {
2862 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2863 		     !inode_is_locked(inode));
2864 	down_write(&EXT4_I(inode)->i_data_sem);
2865 	if (newsize > EXT4_I(inode)->i_disksize)
2866 		EXT4_I(inode)->i_disksize = newsize;
2867 	up_write(&EXT4_I(inode)->i_data_sem);
2868 }
2869 
2870 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
2871 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2872 {
2873 	int changed = 0;
2874 
2875 	if (newsize > inode->i_size) {
2876 		i_size_write(inode, newsize);
2877 		changed = 1;
2878 	}
2879 	if (newsize > EXT4_I(inode)->i_disksize) {
2880 		ext4_update_i_disksize(inode, newsize);
2881 		changed |= 2;
2882 	}
2883 	return changed;
2884 }
2885 
2886 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2887 				      loff_t len);
2888 
2889 struct ext4_group_info {
2890 	unsigned long   bb_state;
2891 	struct rb_root  bb_free_root;
2892 	ext4_grpblk_t	bb_first_free;	/* first free block */
2893 	ext4_grpblk_t	bb_free;	/* total free blocks */
2894 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2895 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2896 	struct          list_head bb_prealloc_list;
2897 #ifdef DOUBLE_CHECK
2898 	void            *bb_bitmap;
2899 #endif
2900 	struct rw_semaphore alloc_sem;
2901 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2902 					 * regions, index is order.
2903 					 * bb_counters[3] = 5 means
2904 					 * 5 free 8-block regions. */
2905 };
2906 
2907 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2908 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2909 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2910 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2911 
2912 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2913 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2914 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2915 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2916 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2917 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2918 
2919 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2920 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2921 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2922 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2923 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2924 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2925 
2926 #define EXT4_MAX_CONTENTION		8
2927 #define EXT4_CONTENTION_THRESHOLD	2
2928 
2929 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2930 					      ext4_group_t group)
2931 {
2932 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2933 }
2934 
2935 /*
2936  * Returns true if the filesystem is busy enough that attempts to
2937  * access the block group locks has run into contention.
2938  */
2939 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2940 {
2941 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2942 }
2943 
2944 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2945 {
2946 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2947 	if (spin_trylock(lock))
2948 		/*
2949 		 * We're able to grab the lock right away, so drop the
2950 		 * lock contention counter.
2951 		 */
2952 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2953 	else {
2954 		/*
2955 		 * The lock is busy, so bump the contention counter,
2956 		 * and then wait on the spin lock.
2957 		 */
2958 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2959 				  EXT4_MAX_CONTENTION);
2960 		spin_lock(lock);
2961 	}
2962 }
2963 
2964 static inline void ext4_unlock_group(struct super_block *sb,
2965 					ext4_group_t group)
2966 {
2967 	spin_unlock(ext4_group_lock_ptr(sb, group));
2968 }
2969 
2970 /*
2971  * Block validity checking
2972  */
2973 #define ext4_check_indirect_blockref(inode, bh)				\
2974 	ext4_check_blockref(__func__, __LINE__, inode,			\
2975 			    (__le32 *)(bh)->b_data,			\
2976 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2977 
2978 #define ext4_ind_check_inode(inode)					\
2979 	ext4_check_blockref(__func__, __LINE__, inode,			\
2980 			    EXT4_I(inode)->i_data,			\
2981 			    EXT4_NDIR_BLOCKS)
2982 
2983 /*
2984  * Inodes and files operations
2985  */
2986 
2987 /* dir.c */
2988 extern const struct file_operations ext4_dir_operations;
2989 
2990 /* file.c */
2991 extern const struct inode_operations ext4_file_inode_operations;
2992 extern const struct file_operations ext4_file_operations;
2993 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2994 
2995 /* inline.c */
2996 extern int ext4_get_max_inline_size(struct inode *inode);
2997 extern int ext4_find_inline_data_nolock(struct inode *inode);
2998 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2999 				 unsigned int len);
3000 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3001 
3002 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
3003 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3004 					 struct inode *inode,
3005 					 loff_t pos, unsigned len,
3006 					 unsigned flags,
3007 					 struct page **pagep);
3008 extern int ext4_write_inline_data_end(struct inode *inode,
3009 				      loff_t pos, unsigned len,
3010 				      unsigned copied,
3011 				      struct page *page);
3012 extern struct buffer_head *
3013 ext4_journalled_write_inline_data(struct inode *inode,
3014 				  unsigned len,
3015 				  struct page *page);
3016 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3017 					   struct inode *inode,
3018 					   loff_t pos, unsigned len,
3019 					   unsigned flags,
3020 					   struct page **pagep,
3021 					   void **fsdata);
3022 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3023 					 unsigned len, unsigned copied,
3024 					 struct page *page);
3025 extern int ext4_try_add_inline_entry(handle_t *handle,
3026 				     struct ext4_filename *fname,
3027 				     struct inode *dir, struct inode *inode);
3028 extern int ext4_try_create_inline_dir(handle_t *handle,
3029 				      struct inode *parent,
3030 				      struct inode *inode);
3031 extern int ext4_read_inline_dir(struct file *filp,
3032 				struct dir_context *ctx,
3033 				int *has_inline_data);
3034 extern int htree_inlinedir_to_tree(struct file *dir_file,
3035 				   struct inode *dir, ext4_lblk_t block,
3036 				   struct dx_hash_info *hinfo,
3037 				   __u32 start_hash, __u32 start_minor_hash,
3038 				   int *has_inline_data);
3039 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3040 					struct ext4_filename *fname,
3041 					const struct qstr *d_name,
3042 					struct ext4_dir_entry_2 **res_dir,
3043 					int *has_inline_data);
3044 extern int ext4_delete_inline_entry(handle_t *handle,
3045 				    struct inode *dir,
3046 				    struct ext4_dir_entry_2 *de_del,
3047 				    struct buffer_head *bh,
3048 				    int *has_inline_data);
3049 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3050 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3051 					struct ext4_dir_entry_2 **parent_de,
3052 					int *retval);
3053 extern int ext4_inline_data_fiemap(struct inode *inode,
3054 				   struct fiemap_extent_info *fieinfo,
3055 				   int *has_inline, __u64 start, __u64 len);
3056 extern int ext4_try_to_evict_inline_data(handle_t *handle,
3057 					 struct inode *inode,
3058 					 int needed);
3059 extern void ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3060 
3061 extern int ext4_convert_inline_data(struct inode *inode);
3062 
3063 static inline int ext4_has_inline_data(struct inode *inode)
3064 {
3065 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3066 	       EXT4_I(inode)->i_inline_off;
3067 }
3068 
3069 /* namei.c */
3070 extern const struct inode_operations ext4_dir_inode_operations;
3071 extern const struct inode_operations ext4_special_inode_operations;
3072 extern struct dentry *ext4_get_parent(struct dentry *child);
3073 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3074 				 struct ext4_dir_entry_2 *de,
3075 				 int blocksize, int csum_size,
3076 				 unsigned int parent_ino, int dotdot_real_len);
3077 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
3078 				   unsigned int blocksize);
3079 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
3080 					 struct inode *inode,
3081 					 struct buffer_head *bh);
3082 #define S_SHIFT 12
3083 static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
3084 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3085 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3086 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3087 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3088 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3089 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3090 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3091 };
3092 
3093 static inline void ext4_set_de_type(struct super_block *sb,
3094 				struct ext4_dir_entry_2 *de,
3095 				umode_t mode) {
3096 	if (ext4_has_feature_filetype(sb))
3097 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3098 }
3099 
3100 /* readpages.c */
3101 extern int ext4_mpage_readpages(struct address_space *mapping,
3102 				struct list_head *pages, struct page *page,
3103 				unsigned nr_pages);
3104 
3105 /* symlink.c */
3106 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3107 extern const struct inode_operations ext4_symlink_inode_operations;
3108 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3109 
3110 /* sysfs.c */
3111 extern int ext4_register_sysfs(struct super_block *sb);
3112 extern void ext4_unregister_sysfs(struct super_block *sb);
3113 extern int __init ext4_init_sysfs(void);
3114 extern void ext4_exit_sysfs(void);
3115 
3116 /* block_validity */
3117 extern void ext4_release_system_zone(struct super_block *sb);
3118 extern int ext4_setup_system_zone(struct super_block *sb);
3119 extern int __init ext4_init_system_zone(void);
3120 extern void ext4_exit_system_zone(void);
3121 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3122 				 ext4_fsblk_t start_blk,
3123 				 unsigned int count);
3124 extern int ext4_check_blockref(const char *, unsigned int,
3125 			       struct inode *, __le32 *, unsigned int);
3126 
3127 /* extents.c */
3128 struct ext4_ext_path;
3129 struct ext4_extent;
3130 
3131 /*
3132  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3133  * __le32.
3134  */
3135 #define EXT_MAX_BLOCKS	0xffffffff
3136 
3137 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
3138 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
3139 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3140 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3141 			       struct ext4_map_blocks *map, int flags);
3142 extern void ext4_ext_truncate(handle_t *, struct inode *);
3143 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3144 				 ext4_lblk_t end);
3145 extern void ext4_ext_init(struct super_block *);
3146 extern void ext4_ext_release(struct super_block *);
3147 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3148 			  loff_t len);
3149 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3150 					  loff_t offset, ssize_t len);
3151 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3152 			   struct ext4_map_blocks *map, int flags);
3153 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
3154 					 ext4_lblk_t lblocks);
3155 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3156 						   int num,
3157 						   struct ext4_ext_path *path);
3158 extern int ext4_can_extents_be_merged(struct inode *inode,
3159 				      struct ext4_extent *ex1,
3160 				      struct ext4_extent *ex2);
3161 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3162 				  struct ext4_ext_path **,
3163 				  struct ext4_extent *, int);
3164 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3165 					      struct ext4_ext_path **,
3166 					      int flags);
3167 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3168 extern int ext4_ext_check_inode(struct inode *inode);
3169 extern int ext4_find_delalloc_range(struct inode *inode,
3170 				    ext4_lblk_t lblk_start,
3171 				    ext4_lblk_t lblk_end);
3172 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
3173 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3174 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3175 			__u64 start, __u64 len);
3176 extern int ext4_ext_precache(struct inode *inode);
3177 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
3178 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
3179 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3180 				struct inode *inode2, ext4_lblk_t lblk1,
3181 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3182 			     int mark_unwritten,int *err);
3183 
3184 /* move_extent.c */
3185 extern void ext4_double_down_write_data_sem(struct inode *first,
3186 					    struct inode *second);
3187 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3188 					  struct inode *donor_inode);
3189 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3190 			     __u64 start_orig, __u64 start_donor,
3191 			     __u64 len, __u64 *moved_len);
3192 
3193 /* page-io.c */
3194 extern int __init ext4_init_pageio(void);
3195 extern void ext4_exit_pageio(void);
3196 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3197 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3198 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3199 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3200 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3201 				struct writeback_control *wbc);
3202 extern void ext4_end_io_rsv_work(struct work_struct *work);
3203 extern void ext4_io_submit(struct ext4_io_submit *io);
3204 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3205 			       struct page *page,
3206 			       int len,
3207 			       struct writeback_control *wbc,
3208 			       bool keep_towrite);
3209 
3210 /* mmp.c */
3211 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3212 
3213 /*
3214  * Add new method to test whether block and inode bitmaps are properly
3215  * initialized. With uninit_bg reading the block from disk is not enough
3216  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3217  */
3218 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3219 
3220 static inline int bitmap_uptodate(struct buffer_head *bh)
3221 {
3222 	return (buffer_uptodate(bh) &&
3223 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3224 }
3225 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3226 {
3227 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3228 }
3229 
3230 /*
3231  * Disable DIO read nolock optimization, so new dioreaders will be forced
3232  * to grab i_mutex
3233  */
3234 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
3235 {
3236 	ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3237 	smp_mb();
3238 }
3239 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
3240 {
3241 	smp_mb();
3242 	ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3243 }
3244 
3245 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3246 
3247 /* For ioend & aio unwritten conversion wait queues */
3248 #define EXT4_WQ_HASH_SZ		37
3249 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3250 					    EXT4_WQ_HASH_SZ])
3251 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3252 
3253 #define EXT4_RESIZING	0
3254 extern int ext4_resize_begin(struct super_block *sb);
3255 extern void ext4_resize_end(struct super_block *sb);
3256 
3257 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3258 					      struct ext4_io_end *io_end)
3259 {
3260 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3261 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3262 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3263 	}
3264 }
3265 
3266 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3267 {
3268 	struct inode *inode = io_end->inode;
3269 
3270 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3271 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3272 		/* Wake up anyone waiting on unwritten extent conversion */
3273 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3274 			wake_up_all(ext4_ioend_wq(inode));
3275 	}
3276 }
3277 
3278 static inline bool ext4_aligned_io(struct inode *inode, loff_t off, loff_t len)
3279 {
3280 	int blksize = 1 << inode->i_blkbits;
3281 
3282 	return IS_ALIGNED(off, blksize) && IS_ALIGNED(len, blksize);
3283 }
3284 
3285 #endif	/* __KERNEL__ */
3286 
3287 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3288 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3289 
3290 #endif	/* _EXT4_H */
3291