1 /*
2  *  ext4.h
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/include/linux/minix_fs.h
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  */
15 
16 #ifndef _EXT4_H
17 #define _EXT4_H
18 
19 #include <linux/types.h>
20 #include <linux/blkdev.h>
21 #include <linux/magic.h>
22 #include <linux/jbd2.h>
23 #include <linux/quota.h>
24 #include <linux/rwsem.h>
25 #include <linux/rbtree.h>
26 #include <linux/seqlock.h>
27 #include <linux/mutex.h>
28 #include <linux/timer.h>
29 #include <linux/wait.h>
30 #include <linux/blockgroup_lock.h>
31 #include <linux/percpu_counter.h>
32 #include <linux/ratelimit.h>
33 #include <crypto/hash.h>
34 #include <linux/falloc.h>
35 #ifdef __KERNEL__
36 #include <linux/compat.h>
37 #endif
38 
39 /*
40  * The fourth extended filesystem constants/structures
41  */
42 
43 /*
44  * Define EXT4FS_DEBUG to produce debug messages
45  */
46 #undef EXT4FS_DEBUG
47 
48 /*
49  * Debug code
50  */
51 #ifdef EXT4FS_DEBUG
52 #define ext4_debug(f, a...)						\
53 	do {								\
54 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
55 			__FILE__, __LINE__, __func__);			\
56 		printk(KERN_DEBUG f, ## a);				\
57 	} while (0)
58 #else
59 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
60 #endif
61 
62 /*
63  * Turn on EXT_DEBUG to get lots of info about extents operations.
64  */
65 #define EXT_DEBUG__
66 #ifdef EXT_DEBUG
67 #define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
68 #else
69 #define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
70 #endif
71 
72 #define EXT4_ERROR_INODE(inode, fmt, a...) \
73 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
74 
75 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
76 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
77 
78 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
79 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
80 
81 /* data type for block offset of block group */
82 typedef int ext4_grpblk_t;
83 
84 /* data type for filesystem-wide blocks number */
85 typedef unsigned long long ext4_fsblk_t;
86 
87 /* data type for file logical block number */
88 typedef __u32 ext4_lblk_t;
89 
90 /* data type for block group number */
91 typedef unsigned int ext4_group_t;
92 
93 /*
94  * Flags used in mballoc's allocation_context flags field.
95  *
96  * Also used to show what's going on for debugging purposes when the
97  * flag field is exported via the traceport interface
98  */
99 
100 /* prefer goal again. length */
101 #define EXT4_MB_HINT_MERGE		0x0001
102 /* blocks already reserved */
103 #define EXT4_MB_HINT_RESERVED		0x0002
104 /* metadata is being allocated */
105 #define EXT4_MB_HINT_METADATA		0x0004
106 /* first blocks in the file */
107 #define EXT4_MB_HINT_FIRST		0x0008
108 /* search for the best chunk */
109 #define EXT4_MB_HINT_BEST		0x0010
110 /* data is being allocated */
111 #define EXT4_MB_HINT_DATA		0x0020
112 /* don't preallocate (for tails) */
113 #define EXT4_MB_HINT_NOPREALLOC		0x0040
114 /* allocate for locality group */
115 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
116 /* allocate goal blocks or none */
117 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
118 /* goal is meaningful */
119 #define EXT4_MB_HINT_TRY_GOAL		0x0200
120 /* blocks already pre-reserved by delayed allocation */
121 #define EXT4_MB_DELALLOC_RESERVED	0x0400
122 /* We are doing stream allocation */
123 #define EXT4_MB_STREAM_ALLOC		0x0800
124 /* Use reserved root blocks if needed */
125 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
126 /* Use blocks from reserved pool */
127 #define EXT4_MB_USE_RESERVED		0x2000
128 
129 struct ext4_allocation_request {
130 	/* target inode for block we're allocating */
131 	struct inode *inode;
132 	/* how many blocks we want to allocate */
133 	unsigned int len;
134 	/* logical block in target inode */
135 	ext4_lblk_t logical;
136 	/* the closest logical allocated block to the left */
137 	ext4_lblk_t lleft;
138 	/* the closest logical allocated block to the right */
139 	ext4_lblk_t lright;
140 	/* phys. target (a hint) */
141 	ext4_fsblk_t goal;
142 	/* phys. block for the closest logical allocated block to the left */
143 	ext4_fsblk_t pleft;
144 	/* phys. block for the closest logical allocated block to the right */
145 	ext4_fsblk_t pright;
146 	/* flags. see above EXT4_MB_HINT_* */
147 	unsigned int flags;
148 };
149 
150 /*
151  * Logical to physical block mapping, used by ext4_map_blocks()
152  *
153  * This structure is used to pass requests into ext4_map_blocks() as
154  * well as to store the information returned by ext4_map_blocks().  It
155  * takes less room on the stack than a struct buffer_head.
156  */
157 #define EXT4_MAP_NEW		(1 << BH_New)
158 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
159 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
160 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
161 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
162 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
163 
164 struct ext4_map_blocks {
165 	ext4_fsblk_t m_pblk;
166 	ext4_lblk_t m_lblk;
167 	unsigned int m_len;
168 	unsigned int m_flags;
169 };
170 
171 /*
172  * Flags for ext4_io_end->flags
173  */
174 #define	EXT4_IO_END_UNWRITTEN	0x0001
175 
176 /*
177  * For converting unwritten extents on a work queue. 'handle' is used for
178  * buffered writeback.
179  */
180 typedef struct ext4_io_end {
181 	struct list_head	list;		/* per-file finished IO list */
182 	handle_t		*handle;	/* handle reserved for extent
183 						 * conversion */
184 	struct inode		*inode;		/* file being written to */
185 	struct bio		*bio;		/* Linked list of completed
186 						 * bios covering the extent */
187 	unsigned int		flag;		/* unwritten or not */
188 	loff_t			offset;		/* offset in the file */
189 	ssize_t			size;		/* size of the extent */
190 	atomic_t		count;		/* reference counter */
191 } ext4_io_end_t;
192 
193 struct ext4_io_submit {
194 	int			io_op;
195 	struct bio		*io_bio;
196 	ext4_io_end_t		*io_end;
197 	sector_t		io_next_block;
198 };
199 
200 /*
201  * Special inodes numbers
202  */
203 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
204 #define EXT4_ROOT_INO		 2	/* Root inode */
205 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
206 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
207 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
208 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
209 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
210 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
211 
212 /* First non-reserved inode for old ext4 filesystems */
213 #define EXT4_GOOD_OLD_FIRST_INO	11
214 
215 /*
216  * Maximal count of links to a file
217  */
218 #define EXT4_LINK_MAX		65000
219 
220 /*
221  * Macro-instructions used to manage several block sizes
222  */
223 #define EXT4_MIN_BLOCK_SIZE		1024
224 #define	EXT4_MAX_BLOCK_SIZE		65536
225 #define EXT4_MIN_BLOCK_LOG_SIZE		10
226 #define EXT4_MAX_BLOCK_LOG_SIZE		16
227 #ifdef __KERNEL__
228 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
229 #else
230 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
231 #endif
232 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
233 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
234 					 EXT4_SB(s)->s_cluster_bits)
235 #ifdef __KERNEL__
236 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
237 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
238 #else
239 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
240 #endif
241 #ifdef __KERNEL__
242 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
243 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
244 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
245 #else
246 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
247 				 EXT4_GOOD_OLD_INODE_SIZE : \
248 				 (s)->s_inode_size)
249 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
250 				 EXT4_GOOD_OLD_FIRST_INO : \
251 				 (s)->s_first_ino)
252 #endif
253 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
254 
255 /* Translate a block number to a cluster number */
256 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
257 /* Translate a cluster number to a block number */
258 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
259 /* Translate # of blks to # of clusters */
260 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
261 				 (sbi)->s_cluster_bits)
262 /* Mask out the low bits to get the starting block of the cluster */
263 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
264 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
265 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
266 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
267 /* Get the cluster offset */
268 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
269 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
270 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
271 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
272 
273 /*
274  * Structure of a blocks group descriptor
275  */
276 struct ext4_group_desc
277 {
278 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
279 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
280 	__le32	bg_inode_table_lo;	/* Inodes table block */
281 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
282 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
283 	__le16	bg_used_dirs_count_lo;	/* Directories count */
284 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
285 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
286 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
287 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
288 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
289 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
290 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
291 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
292 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
293 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
294 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
295 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
296 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
297 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
298 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
299 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
300 	__u32   bg_reserved;
301 };
302 
303 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
304 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
305 	 sizeof(__le16))
306 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
307 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
308 	 sizeof(__le16))
309 
310 /*
311  * Structure of a flex block group info
312  */
313 
314 struct flex_groups {
315 	atomic64_t	free_clusters;
316 	atomic_t	free_inodes;
317 	atomic_t	used_dirs;
318 };
319 
320 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
321 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
322 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
323 
324 /*
325  * Macro-instructions used to manage group descriptors
326  */
327 #define EXT4_MIN_DESC_SIZE		32
328 #define EXT4_MIN_DESC_SIZE_64BIT	64
329 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
330 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
331 #ifdef __KERNEL__
332 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
333 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
334 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
335 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
336 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
337 #else
338 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
339 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
340 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
341 #endif
342 
343 /*
344  * Constants relative to the data blocks
345  */
346 #define	EXT4_NDIR_BLOCKS		12
347 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
348 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
349 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
350 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
351 
352 /*
353  * Inode flags
354  */
355 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
356 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
357 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
358 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
359 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
360 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
361 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
362 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
363 /* Reserved for compression usage... */
364 #define EXT4_DIRTY_FL			0x00000100
365 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
366 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
367 	/* nb: was previously EXT2_ECOMPR_FL */
368 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
369 /* End compression flags --- maybe not all used */
370 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
371 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
372 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
373 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
374 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
375 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
376 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
377 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
378 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
379 #define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
380 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
381 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
382 
383 #define EXT4_FL_USER_VISIBLE		0x004BDFFF /* User visible flags */
384 #define EXT4_FL_USER_MODIFIABLE		0x004380FF /* User modifiable flags */
385 
386 /* Flags that should be inherited by new inodes from their parent. */
387 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
388 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
389 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
390 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
391 
392 /* Flags that are appropriate for regular files (all but dir-specific ones). */
393 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
394 
395 /* Flags that are appropriate for non-directories/regular files. */
396 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
397 
398 /* Mask out flags that are inappropriate for the given type of inode. */
ext4_mask_flags(umode_t mode,__u32 flags)399 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
400 {
401 	if (S_ISDIR(mode))
402 		return flags;
403 	else if (S_ISREG(mode))
404 		return flags & EXT4_REG_FLMASK;
405 	else
406 		return flags & EXT4_OTHER_FLMASK;
407 }
408 
409 /*
410  * Inode flags used for atomic set/get
411  */
412 enum {
413 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
414 	EXT4_INODE_UNRM		= 1,	/* Undelete */
415 	EXT4_INODE_COMPR	= 2,	/* Compress file */
416 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
417 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
418 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
419 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
420 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
421 /* Reserved for compression usage... */
422 	EXT4_INODE_DIRTY	= 8,
423 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
424 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
425 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
426 /* End compression flags --- maybe not all used */
427 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
428 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
429 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
430 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
431 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
432 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
433 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
434 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
435 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
436 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
437 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
438 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
439 };
440 
441 /*
442  * Since it's pretty easy to mix up bit numbers and hex values, we use a
443  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
444  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
445  * any extra space in the compiled kernel image, otherwise, the build will fail.
446  * It's important that these values are the same, since we are using
447  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
448  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
449  * values found in ext2, ext3 and ext4 filesystems, and of course the values
450  * defined in e2fsprogs.
451  *
452  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
453  */
454 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
455 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
456 
ext4_check_flag_values(void)457 static inline void ext4_check_flag_values(void)
458 {
459 	CHECK_FLAG_VALUE(SECRM);
460 	CHECK_FLAG_VALUE(UNRM);
461 	CHECK_FLAG_VALUE(COMPR);
462 	CHECK_FLAG_VALUE(SYNC);
463 	CHECK_FLAG_VALUE(IMMUTABLE);
464 	CHECK_FLAG_VALUE(APPEND);
465 	CHECK_FLAG_VALUE(NODUMP);
466 	CHECK_FLAG_VALUE(NOATIME);
467 	CHECK_FLAG_VALUE(DIRTY);
468 	CHECK_FLAG_VALUE(COMPRBLK);
469 	CHECK_FLAG_VALUE(NOCOMPR);
470 	CHECK_FLAG_VALUE(ENCRYPT);
471 	CHECK_FLAG_VALUE(INDEX);
472 	CHECK_FLAG_VALUE(IMAGIC);
473 	CHECK_FLAG_VALUE(JOURNAL_DATA);
474 	CHECK_FLAG_VALUE(NOTAIL);
475 	CHECK_FLAG_VALUE(DIRSYNC);
476 	CHECK_FLAG_VALUE(TOPDIR);
477 	CHECK_FLAG_VALUE(HUGE_FILE);
478 	CHECK_FLAG_VALUE(EXTENTS);
479 	CHECK_FLAG_VALUE(EA_INODE);
480 	CHECK_FLAG_VALUE(EOFBLOCKS);
481 	CHECK_FLAG_VALUE(INLINE_DATA);
482 	CHECK_FLAG_VALUE(RESERVED);
483 }
484 
485 /* Used to pass group descriptor data when online resize is done */
486 struct ext4_new_group_input {
487 	__u32 group;		/* Group number for this data */
488 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
489 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
490 	__u64 inode_table;	/* Absolute block number of inode table start */
491 	__u32 blocks_count;	/* Total number of blocks in this group */
492 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
493 	__u16 unused;
494 };
495 
496 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
497 struct compat_ext4_new_group_input {
498 	u32 group;
499 	compat_u64 block_bitmap;
500 	compat_u64 inode_bitmap;
501 	compat_u64 inode_table;
502 	u32 blocks_count;
503 	u16 reserved_blocks;
504 	u16 unused;
505 };
506 #endif
507 
508 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
509 struct ext4_new_group_data {
510 	__u32 group;
511 	__u64 block_bitmap;
512 	__u64 inode_bitmap;
513 	__u64 inode_table;
514 	__u32 blocks_count;
515 	__u16 reserved_blocks;
516 	__u16 unused;
517 	__u32 free_blocks_count;
518 };
519 
520 /* Indexes used to index group tables in ext4_new_group_data */
521 enum {
522 	BLOCK_BITMAP = 0,	/* block bitmap */
523 	INODE_BITMAP,		/* inode bitmap */
524 	INODE_TABLE,		/* inode tables */
525 	GROUP_TABLE_COUNT,
526 };
527 
528 /*
529  * Flags used by ext4_map_blocks()
530  */
531 	/* Allocate any needed blocks and/or convert an unwritten
532 	   extent to be an initialized ext4 */
533 #define EXT4_GET_BLOCKS_CREATE			0x0001
534 	/* Request the creation of an unwritten extent */
535 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
536 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
537 						 EXT4_GET_BLOCKS_CREATE)
538 	/* Caller is from the delayed allocation writeout path
539 	 * finally doing the actual allocation of delayed blocks */
540 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
541 	/* caller is from the direct IO path, request to creation of an
542 	unwritten extents if not allocated, split the unwritten
543 	extent if blocks has been preallocated already*/
544 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
545 #define EXT4_GET_BLOCKS_CONVERT			0x0010
546 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
547 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
548 	/* Convert extent to initialized after IO complete */
549 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
550 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
551 	/* Eventual metadata allocation (due to growing extent tree)
552 	 * should not fail, so try to use reserved blocks for that.*/
553 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
554 	/* Don't normalize allocation size (used for fallocate) */
555 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
556 	/* Request will not result in inode size update (user for fallocate) */
557 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
558 	/* Do not take i_data_sem locking in ext4_map_blocks */
559 #define EXT4_GET_BLOCKS_NO_LOCK			0x0100
560 	/* Convert written extents to unwritten */
561 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0200
562 
563 /*
564  * The bit position of these flags must not overlap with any of the
565  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
566  * read_extent_tree_block(), ext4_split_extent_at(),
567  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
568  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
569  * caching the extents when reading from the extent tree while a
570  * truncate or punch hole operation is in progress.
571  */
572 #define EXT4_EX_NOCACHE				0x40000000
573 #define EXT4_EX_FORCE_CACHE			0x20000000
574 
575 /*
576  * Flags used by ext4_free_blocks
577  */
578 #define EXT4_FREE_BLOCKS_METADATA	0x0001
579 #define EXT4_FREE_BLOCKS_FORGET		0x0002
580 #define EXT4_FREE_BLOCKS_VALIDATED	0x0004
581 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE	0x0008
582 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
583 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
584 
585 /* Encryption algorithms */
586 #define EXT4_ENCRYPTION_MODE_INVALID		0
587 #define EXT4_ENCRYPTION_MODE_AES_256_XTS	1
588 #define EXT4_ENCRYPTION_MODE_AES_256_GCM	2
589 #define EXT4_ENCRYPTION_MODE_AES_256_CBC	3
590 #define EXT4_ENCRYPTION_MODE_AES_256_CTS	4
591 
592 #include "ext4_crypto.h"
593 
594 /*
595  * ioctl commands
596  */
597 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
598 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
599 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
600 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
601 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
602 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
603 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
604 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
605 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
606 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
607 #define EXT4_IOC_MIGRATE		_IO('f', 9)
608  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
609  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
610 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
611 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
612 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
613 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
614 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
615 #define EXT4_IOC_SET_ENCRYPTION_POLICY	_IOR('f', 19, struct ext4_encryption_policy)
616 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	_IOW('f', 20, __u8[16])
617 #define EXT4_IOC_GET_ENCRYPTION_POLICY	_IOW('f', 21, struct ext4_encryption_policy)
618 
619 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
620 /*
621  * ioctl commands in 32 bit emulation
622  */
623 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
624 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
625 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
626 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
627 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
628 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
629 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
630 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
631 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
632 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
633 #endif
634 
635 /* Max physical block we can address w/o extents */
636 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
637 
638 /*
639  * Structure of an inode on the disk
640  */
641 struct ext4_inode {
642 	__le16	i_mode;		/* File mode */
643 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
644 	__le32	i_size_lo;	/* Size in bytes */
645 	__le32	i_atime;	/* Access time */
646 	__le32	i_ctime;	/* Inode Change time */
647 	__le32	i_mtime;	/* Modification time */
648 	__le32	i_dtime;	/* Deletion Time */
649 	__le16	i_gid;		/* Low 16 bits of Group Id */
650 	__le16	i_links_count;	/* Links count */
651 	__le32	i_blocks_lo;	/* Blocks count */
652 	__le32	i_flags;	/* File flags */
653 	union {
654 		struct {
655 			__le32  l_i_version;
656 		} linux1;
657 		struct {
658 			__u32  h_i_translator;
659 		} hurd1;
660 		struct {
661 			__u32  m_i_reserved1;
662 		} masix1;
663 	} osd1;				/* OS dependent 1 */
664 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
665 	__le32	i_generation;	/* File version (for NFS) */
666 	__le32	i_file_acl_lo;	/* File ACL */
667 	__le32	i_size_high;
668 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
669 	union {
670 		struct {
671 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
672 			__le16	l_i_file_acl_high;
673 			__le16	l_i_uid_high;	/* these 2 fields */
674 			__le16	l_i_gid_high;	/* were reserved2[0] */
675 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
676 			__le16	l_i_reserved;
677 		} linux2;
678 		struct {
679 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
680 			__u16	h_i_mode_high;
681 			__u16	h_i_uid_high;
682 			__u16	h_i_gid_high;
683 			__u32	h_i_author;
684 		} hurd2;
685 		struct {
686 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
687 			__le16	m_i_file_acl_high;
688 			__u32	m_i_reserved2[2];
689 		} masix2;
690 	} osd2;				/* OS dependent 2 */
691 	__le16	i_extra_isize;
692 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
693 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
694 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
695 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
696 	__le32  i_crtime;       /* File Creation time */
697 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
698 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
699 };
700 
701 struct move_extent {
702 	__u32 reserved;		/* should be zero */
703 	__u32 donor_fd;		/* donor file descriptor */
704 	__u64 orig_start;	/* logical start offset in block for orig */
705 	__u64 donor_start;	/* logical start offset in block for donor */
706 	__u64 len;		/* block length to be moved */
707 	__u64 moved_len;	/* moved block length */
708 };
709 
710 #define EXT4_EPOCH_BITS 2
711 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
712 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
713 
714 /*
715  * Extended fields will fit into an inode if the filesystem was formatted
716  * with large inodes (-I 256 or larger) and there are not currently any EAs
717  * consuming all of the available space. For new inodes we always reserve
718  * enough space for the kernel's known extended fields, but for inodes
719  * created with an old kernel this might not have been the case. None of
720  * the extended inode fields is critical for correct filesystem operation.
721  * This macro checks if a certain field fits in the inode. Note that
722  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
723  */
724 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
725 	((offsetof(typeof(*ext4_inode), field) +	\
726 	  sizeof((ext4_inode)->field))			\
727 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
728 	    (einode)->i_extra_isize))			\
729 
ext4_encode_extra_time(struct timespec * time)730 static inline __le32 ext4_encode_extra_time(struct timespec *time)
731 {
732        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
733 			   (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
734                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
735 }
736 
ext4_decode_extra_time(struct timespec * time,__le32 extra)737 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
738 {
739        if (sizeof(time->tv_sec) > 4)
740 	       time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
741 			       << 32;
742        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
743 }
744 
745 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)			       \
746 do {									       \
747 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	       \
748 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
749 		(raw_inode)->xtime ## _extra =				       \
750 				ext4_encode_extra_time(&(inode)->xtime);       \
751 } while (0)
752 
753 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
754 do {									       \
755 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
756 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
757 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
758 		(raw_inode)->xtime ## _extra =				       \
759 				ext4_encode_extra_time(&(einode)->xtime);      \
760 } while (0)
761 
762 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)			       \
763 do {									       \
764 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
765 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
766 		ext4_decode_extra_time(&(inode)->xtime,			       \
767 				       raw_inode->xtime ## _extra);	       \
768 	else								       \
769 		(inode)->xtime.tv_nsec = 0;				       \
770 } while (0)
771 
772 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
773 do {									       \
774 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
775 		(einode)->xtime.tv_sec = 				       \
776 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
777 	else								       \
778 		(einode)->xtime.tv_sec = 0;				       \
779 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
780 		ext4_decode_extra_time(&(einode)->xtime,		       \
781 				       raw_inode->xtime ## _extra);	       \
782 	else								       \
783 		(einode)->xtime.tv_nsec = 0;				       \
784 } while (0)
785 
786 #define i_disk_version osd1.linux1.l_i_version
787 
788 #if defined(__KERNEL__) || defined(__linux__)
789 #define i_reserved1	osd1.linux1.l_i_reserved1
790 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
791 #define i_blocks_high	osd2.linux2.l_i_blocks_high
792 #define i_uid_low	i_uid
793 #define i_gid_low	i_gid
794 #define i_uid_high	osd2.linux2.l_i_uid_high
795 #define i_gid_high	osd2.linux2.l_i_gid_high
796 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
797 
798 #elif defined(__GNU__)
799 
800 #define i_translator	osd1.hurd1.h_i_translator
801 #define i_uid_high	osd2.hurd2.h_i_uid_high
802 #define i_gid_high	osd2.hurd2.h_i_gid_high
803 #define i_author	osd2.hurd2.h_i_author
804 
805 #elif defined(__masix__)
806 
807 #define i_reserved1	osd1.masix1.m_i_reserved1
808 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
809 #define i_reserved2	osd2.masix2.m_i_reserved2
810 
811 #endif /* defined(__KERNEL__) || defined(__linux__) */
812 
813 #include "extents_status.h"
814 
815 /*
816  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
817  *
818  * These are needed to avoid lockdep false positives when we need to
819  * allocate blocks to the quota inode during ext4_map_blocks(), while
820  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
821  * do quota tracking for the quota inode, this avoids deadlock (as
822  * well as infinite recursion, since it isn't turtles all the way
823  * down...)
824  *
825  *  I_DATA_SEM_NORMAL - Used for most inodes
826  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
827  *			  where the second inode has larger inode number
828  *			  than the first
829  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
830  */
831 enum {
832 	I_DATA_SEM_NORMAL = 0,
833 	I_DATA_SEM_OTHER,
834 	I_DATA_SEM_QUOTA,
835 };
836 
837 
838 /*
839  * fourth extended file system inode data in memory
840  */
841 struct ext4_inode_info {
842 	__le32	i_data[15];	/* unconverted */
843 	__u32	i_dtime;
844 	ext4_fsblk_t	i_file_acl;
845 
846 	/*
847 	 * i_block_group is the number of the block group which contains
848 	 * this file's inode.  Constant across the lifetime of the inode,
849 	 * it is ued for making block allocation decisions - we try to
850 	 * place a file's data blocks near its inode block, and new inodes
851 	 * near to their parent directory's inode.
852 	 */
853 	ext4_group_t	i_block_group;
854 	ext4_lblk_t	i_dir_start_lookup;
855 #if (BITS_PER_LONG < 64)
856 	unsigned long	i_state_flags;		/* Dynamic state flags */
857 #endif
858 	unsigned long	i_flags;
859 
860 	/*
861 	 * Extended attributes can be read independently of the main file
862 	 * data. Taking i_mutex even when reading would cause contention
863 	 * between readers of EAs and writers of regular file data, so
864 	 * instead we synchronize on xattr_sem when reading or changing
865 	 * EAs.
866 	 */
867 	struct rw_semaphore xattr_sem;
868 
869 	struct list_head i_orphan;	/* unlinked but open inodes */
870 
871 	/*
872 	 * i_disksize keeps track of what the inode size is ON DISK, not
873 	 * in memory.  During truncate, i_size is set to the new size by
874 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
875 	 * set i_disksize to 0 until the truncate is actually under way.
876 	 *
877 	 * The intent is that i_disksize always represents the blocks which
878 	 * are used by this file.  This allows recovery to restart truncate
879 	 * on orphans if we crash during truncate.  We actually write i_disksize
880 	 * into the on-disk inode when writing inodes out, instead of i_size.
881 	 *
882 	 * The only time when i_disksize and i_size may be different is when
883 	 * a truncate is in progress.  The only things which change i_disksize
884 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
885 	 */
886 	loff_t	i_disksize;
887 
888 	/*
889 	 * i_data_sem is for serialising ext4_truncate() against
890 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
891 	 * data tree are chopped off during truncate. We can't do that in
892 	 * ext4 because whenever we perform intermediate commits during
893 	 * truncate, the inode and all the metadata blocks *must* be in a
894 	 * consistent state which allows truncation of the orphans to restart
895 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
896 	 * by other means, so we have i_data_sem.
897 	 */
898 	struct rw_semaphore i_data_sem;
899 	/*
900 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
901 	 * operations. We have to make sure that new page cannot be faulted in
902 	 * a section of the inode that is being punched. We cannot easily use
903 	 * i_data_sem for this since we need protection for the whole punch
904 	 * operation and i_data_sem ranks below transaction start so we have
905 	 * to occasionally drop it.
906 	 */
907 	struct rw_semaphore i_mmap_sem;
908 	struct inode vfs_inode;
909 	struct jbd2_inode *jinode;
910 
911 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
912 
913 	/*
914 	 * File creation time. Its function is same as that of
915 	 * struct timespec i_{a,c,m}time in the generic inode.
916 	 */
917 	struct timespec i_crtime;
918 
919 	/* mballoc */
920 	struct list_head i_prealloc_list;
921 	spinlock_t i_prealloc_lock;
922 
923 	/* extents status tree */
924 	struct ext4_es_tree i_es_tree;
925 	rwlock_t i_es_lock;
926 	struct list_head i_es_list;
927 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
928 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
929 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
930 					   extents to shrink. Protected by
931 					   i_es_lock  */
932 
933 	/* ialloc */
934 	ext4_group_t	i_last_alloc_group;
935 
936 	/* allocation reservation info for delalloc */
937 	/* In case of bigalloc, these refer to clusters rather than blocks */
938 	unsigned int i_reserved_data_blocks;
939 	unsigned int i_reserved_meta_blocks;
940 	unsigned int i_allocated_meta_blocks;
941 	ext4_lblk_t i_da_metadata_calc_last_lblock;
942 	int i_da_metadata_calc_len;
943 
944 	/* on-disk additional length */
945 	__u16 i_extra_isize;
946 	char i_crypt_policy_flags;
947 
948 	/* Indicate the inline data space. */
949 	u16 i_inline_off;
950 	u16 i_inline_size;
951 
952 #ifdef CONFIG_QUOTA
953 	/* quota space reservation, managed internally by quota code */
954 	qsize_t i_reserved_quota;
955 #endif
956 
957 	/* Lock protecting lists below */
958 	spinlock_t i_completed_io_lock;
959 	/*
960 	 * Completed IOs that need unwritten extents handling and have
961 	 * transaction reserved
962 	 */
963 	struct list_head i_rsv_conversion_list;
964 	/*
965 	 * Completed IOs that need unwritten extents handling and don't have
966 	 * transaction reserved
967 	 */
968 	atomic_t i_ioend_count;	/* Number of outstanding io_end structs */
969 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
970 	struct work_struct i_rsv_conversion_work;
971 
972 	spinlock_t i_block_reservation_lock;
973 
974 	/*
975 	 * Transactions that contain inode's metadata needed to complete
976 	 * fsync and fdatasync, respectively.
977 	 */
978 	tid_t i_sync_tid;
979 	tid_t i_datasync_tid;
980 
981 #ifdef CONFIG_QUOTA
982 	struct dquot *i_dquot[MAXQUOTAS];
983 #endif
984 
985 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
986 	__u32 i_csum_seed;
987 
988 #ifdef CONFIG_EXT4_FS_ENCRYPTION
989 	/* Encryption params */
990 	struct ext4_encryption_key i_encryption_key;
991 #endif
992 };
993 
994 /*
995  * File system states
996  */
997 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
998 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
999 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1000 
1001 /*
1002  * Misc. filesystem flags
1003  */
1004 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1005 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1006 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1007 
1008 /*
1009  * Mount flags set via mount options or defaults
1010  */
1011 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1012 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1013 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1014 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1015 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1016 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1017 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1018 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1019 #ifdef CONFIG_FS_DAX
1020 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
1021 #else
1022 #define EXT4_MOUNT_DAX			0
1023 #endif
1024 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1025 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1026 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1027 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1028 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1029 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1030 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1031 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1032 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1033 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1034 #define EXT4_MOUNT_QUOTA		0x80000 /* Some quota option set */
1035 #define EXT4_MOUNT_USRQUOTA		0x100000 /* "old" user quota */
1036 #define EXT4_MOUNT_GRPQUOTA		0x200000 /* "old" group quota */
1037 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1038 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1039 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1040 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1041 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1042 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1043 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1044 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1045 
1046 /*
1047  * Mount flags set either automatically (could not be set by mount option)
1048  * based on per file system feature or property or in special cases such as
1049  * distinguishing between explicit mount option definition and default.
1050  */
1051 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1052 						      specified delalloc */
1053 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1054 						      size of blocksize * 8
1055 						      blocks */
1056 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1057 						      file systems */
1058 
1059 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1060 						~EXT4_MOUNT_##opt
1061 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1062 						EXT4_MOUNT_##opt
1063 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1064 					 EXT4_MOUNT_##opt)
1065 
1066 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1067 						~EXT4_MOUNT2_##opt
1068 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1069 						EXT4_MOUNT2_##opt
1070 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1071 					 EXT4_MOUNT2_##opt)
1072 
1073 #define ext4_test_and_set_bit		__test_and_set_bit_le
1074 #define ext4_set_bit			__set_bit_le
1075 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1076 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1077 #define ext4_clear_bit			__clear_bit_le
1078 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1079 #define ext4_test_bit			test_bit_le
1080 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1081 #define ext4_find_next_bit		find_next_bit_le
1082 
1083 extern void ext4_set_bits(void *bm, int cur, int len);
1084 
1085 /*
1086  * Maximal mount counts between two filesystem checks
1087  */
1088 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1089 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1090 
1091 /*
1092  * Behaviour when detecting errors
1093  */
1094 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1095 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1096 #define EXT4_ERRORS_PANIC		3	/* Panic */
1097 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1098 
1099 /* Metadata checksum algorithm codes */
1100 #define EXT4_CRC32C_CHKSUM		1
1101 
1102 /*
1103  * Structure of the super block
1104  */
1105 struct ext4_super_block {
1106 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1107 	__le32	s_blocks_count_lo;	/* Blocks count */
1108 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1109 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1110 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1111 	__le32	s_first_data_block;	/* First Data Block */
1112 	__le32	s_log_block_size;	/* Block size */
1113 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1114 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1115 	__le32	s_clusters_per_group;	/* # Clusters per group */
1116 	__le32	s_inodes_per_group;	/* # Inodes per group */
1117 	__le32	s_mtime;		/* Mount time */
1118 /*30*/	__le32	s_wtime;		/* Write time */
1119 	__le16	s_mnt_count;		/* Mount count */
1120 	__le16	s_max_mnt_count;	/* Maximal mount count */
1121 	__le16	s_magic;		/* Magic signature */
1122 	__le16	s_state;		/* File system state */
1123 	__le16	s_errors;		/* Behaviour when detecting errors */
1124 	__le16	s_minor_rev_level;	/* minor revision level */
1125 /*40*/	__le32	s_lastcheck;		/* time of last check */
1126 	__le32	s_checkinterval;	/* max. time between checks */
1127 	__le32	s_creator_os;		/* OS */
1128 	__le32	s_rev_level;		/* Revision level */
1129 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1130 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1131 	/*
1132 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1133 	 *
1134 	 * Note: the difference between the compatible feature set and
1135 	 * the incompatible feature set is that if there is a bit set
1136 	 * in the incompatible feature set that the kernel doesn't
1137 	 * know about, it should refuse to mount the filesystem.
1138 	 *
1139 	 * e2fsck's requirements are more strict; if it doesn't know
1140 	 * about a feature in either the compatible or incompatible
1141 	 * feature set, it must abort and not try to meddle with
1142 	 * things it doesn't understand...
1143 	 */
1144 	__le32	s_first_ino;		/* First non-reserved inode */
1145 	__le16  s_inode_size;		/* size of inode structure */
1146 	__le16	s_block_group_nr;	/* block group # of this superblock */
1147 	__le32	s_feature_compat;	/* compatible feature set */
1148 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1149 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1150 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1151 /*78*/	char	s_volume_name[16];	/* volume name */
1152 /*88*/	char	s_last_mounted[64];	/* directory where last mounted */
1153 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1154 	/*
1155 	 * Performance hints.  Directory preallocation should only
1156 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1157 	 */
1158 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1159 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1160 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1161 	/*
1162 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1163 	 */
1164 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1165 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1166 	__le32	s_journal_dev;		/* device number of journal file */
1167 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1168 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1169 	__u8	s_def_hash_version;	/* Default hash version to use */
1170 	__u8	s_jnl_backup_type;
1171 	__le16  s_desc_size;		/* size of group descriptor */
1172 /*100*/	__le32	s_default_mount_opts;
1173 	__le32	s_first_meta_bg;	/* First metablock block group */
1174 	__le32	s_mkfs_time;		/* When the filesystem was created */
1175 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1176 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1177 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1178 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1179 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1180 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1181 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1182 	__le32	s_flags;		/* Miscellaneous flags */
1183 	__le16  s_raid_stride;		/* RAID stride */
1184 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1185 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1186 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1187 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1188 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1189 	__u8	s_encryption_level;	/* versioning level for encryption */
1190 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1191 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1192 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1193 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1194 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1195 					      snapshot's future use */
1196 	__le32	s_snapshot_list;	/* inode number of the head of the
1197 					   on-disk snapshot list */
1198 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1199 	__le32	s_error_count;		/* number of fs errors */
1200 	__le32	s_first_error_time;	/* first time an error happened */
1201 	__le32	s_first_error_ino;	/* inode involved in first error */
1202 	__le64	s_first_error_block;	/* block involved of first error */
1203 	__u8	s_first_error_func[32];	/* function where the error happened */
1204 	__le32	s_first_error_line;	/* line number where error happened */
1205 	__le32	s_last_error_time;	/* most recent time of an error */
1206 	__le32	s_last_error_ino;	/* inode involved in last error */
1207 	__le32	s_last_error_line;	/* line number where error happened */
1208 	__le64	s_last_error_block;	/* block involved of last error */
1209 	__u8	s_last_error_func[32];	/* function where the error happened */
1210 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1211 	__u8	s_mount_opts[64];
1212 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1213 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1214 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1215 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1216 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1217 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1218 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1219 	__le32	s_reserved[100];	/* Padding to the end of the block */
1220 	__le32	s_checksum;		/* crc32c(superblock) */
1221 };
1222 
1223 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1224 
1225 #ifdef __KERNEL__
1226 
1227 /*
1228  * run-time mount flags
1229  */
1230 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1231 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1232 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1233 
1234 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1235 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1236 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1237 #else
1238 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1239 #endif
1240 
1241 /* Number of quota types we support */
1242 #define EXT4_MAXQUOTAS 2
1243 
1244 /*
1245  * fourth extended-fs super-block data in memory
1246  */
1247 struct ext4_sb_info {
1248 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1249 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1250 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1251 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1252 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1253 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1254 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1255 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1256 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1257 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1258 	unsigned long s_overhead;  /* # of fs overhead clusters */
1259 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1260 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1261 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1262 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1263 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1264 	struct buffer_head **s_group_desc;
1265 	unsigned int s_mount_opt;
1266 	unsigned int s_mount_opt2;
1267 	unsigned int s_mount_flags;
1268 	unsigned int s_def_mount_opt;
1269 	ext4_fsblk_t s_sb_block;
1270 	atomic64_t s_resv_clusters;
1271 	kuid_t s_resuid;
1272 	kgid_t s_resgid;
1273 	unsigned short s_mount_state;
1274 	unsigned short s_pad;
1275 	int s_addr_per_block_bits;
1276 	int s_desc_per_block_bits;
1277 	int s_inode_size;
1278 	int s_first_ino;
1279 	unsigned int s_inode_readahead_blks;
1280 	unsigned int s_inode_goal;
1281 	spinlock_t s_next_gen_lock;
1282 	u32 s_next_generation;
1283 	u32 s_hash_seed[4];
1284 	int s_def_hash_version;
1285 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1286 	struct percpu_counter s_freeclusters_counter;
1287 	struct percpu_counter s_freeinodes_counter;
1288 	struct percpu_counter s_dirs_counter;
1289 	struct percpu_counter s_dirtyclusters_counter;
1290 	struct blockgroup_lock *s_blockgroup_lock;
1291 	struct proc_dir_entry *s_proc;
1292 	struct kobject s_kobj;
1293 	struct completion s_kobj_unregister;
1294 	struct super_block *s_sb;
1295 
1296 	/* Journaling */
1297 	struct journal_s *s_journal;
1298 	struct list_head s_orphan;
1299 	struct mutex s_orphan_lock;
1300 	unsigned long s_resize_flags;		/* Flags indicating if there
1301 						   is a resizer */
1302 	unsigned long s_commit_interval;
1303 	u32 s_max_batch_time;
1304 	u32 s_min_batch_time;
1305 	struct block_device *journal_bdev;
1306 #ifdef CONFIG_QUOTA
1307 	char *s_qf_names[EXT4_MAXQUOTAS];	/* Names of quota files with journalled quota */
1308 	int s_jquota_fmt;			/* Format of quota to use */
1309 #endif
1310 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1311 	struct rb_root system_blks;
1312 
1313 #ifdef EXTENTS_STATS
1314 	/* ext4 extents stats */
1315 	unsigned long s_ext_min;
1316 	unsigned long s_ext_max;
1317 	unsigned long s_depth_max;
1318 	spinlock_t s_ext_stats_lock;
1319 	unsigned long s_ext_blocks;
1320 	unsigned long s_ext_extents;
1321 #endif
1322 
1323 	/* for buddy allocator */
1324 	struct ext4_group_info ***s_group_info;
1325 	struct inode *s_buddy_cache;
1326 	spinlock_t s_md_lock;
1327 	unsigned short *s_mb_offsets;
1328 	unsigned int *s_mb_maxs;
1329 	unsigned int s_group_info_size;
1330 
1331 	/* tunables */
1332 	unsigned long s_stripe;
1333 	unsigned int s_mb_stream_request;
1334 	unsigned int s_mb_max_to_scan;
1335 	unsigned int s_mb_min_to_scan;
1336 	unsigned int s_mb_stats;
1337 	unsigned int s_mb_order2_reqs;
1338 	unsigned int s_mb_group_prealloc;
1339 	unsigned int s_max_dir_size_kb;
1340 	/* where last allocation was done - for stream allocation */
1341 	unsigned long s_mb_last_group;
1342 	unsigned long s_mb_last_start;
1343 
1344 	/* stats for buddy allocator */
1345 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1346 	atomic_t s_bal_success;	/* we found long enough chunks */
1347 	atomic_t s_bal_allocated;	/* in blocks */
1348 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1349 	atomic_t s_bal_goals;	/* goal hits */
1350 	atomic_t s_bal_breaks;	/* too long searches */
1351 	atomic_t s_bal_2orders;	/* 2^order hits */
1352 	spinlock_t s_bal_lock;
1353 	unsigned long s_mb_buddies_generated;
1354 	unsigned long long s_mb_generation_time;
1355 	atomic_t s_mb_lost_chunks;
1356 	atomic_t s_mb_preallocated;
1357 	atomic_t s_mb_discarded;
1358 	atomic_t s_lock_busy;
1359 
1360 	/* locality groups */
1361 	struct ext4_locality_group __percpu *s_locality_groups;
1362 
1363 	/* for write statistics */
1364 	unsigned long s_sectors_written_start;
1365 	u64 s_kbytes_written;
1366 
1367 	/* the size of zero-out chunk */
1368 	unsigned int s_extent_max_zeroout_kb;
1369 
1370 	unsigned int s_log_groups_per_flex;
1371 	struct flex_groups *s_flex_groups;
1372 	ext4_group_t s_flex_groups_allocated;
1373 
1374 	/* workqueue for reserved extent conversions (buffered io) */
1375 	struct workqueue_struct *rsv_conversion_wq;
1376 
1377 	/* timer for periodic error stats printing */
1378 	struct timer_list s_err_report;
1379 
1380 	/* Lazy inode table initialization info */
1381 	struct ext4_li_request *s_li_request;
1382 	/* Wait multiplier for lazy initialization thread */
1383 	unsigned int s_li_wait_mult;
1384 
1385 	/* Kernel thread for multiple mount protection */
1386 	struct task_struct *s_mmp_tsk;
1387 
1388 	/* record the last minlen when FITRIM is called. */
1389 	atomic_t s_last_trim_minblks;
1390 
1391 	/* Reference to checksum algorithm driver via cryptoapi */
1392 	struct crypto_shash *s_chksum_driver;
1393 
1394 	/* Precomputed FS UUID checksum for seeding other checksums */
1395 	__u32 s_csum_seed;
1396 
1397 	/* Reclaim extents from extent status tree */
1398 	struct shrinker s_es_shrinker;
1399 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1400 	long s_es_nr_inode;
1401 	struct ext4_es_stats s_es_stats;
1402 	struct mb_cache *s_mb_cache;
1403 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1404 
1405 	/* Ratelimit ext4 messages. */
1406 	struct ratelimit_state s_err_ratelimit_state;
1407 	struct ratelimit_state s_warning_ratelimit_state;
1408 	struct ratelimit_state s_msg_ratelimit_state;
1409 
1410 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1411 	/* Encryption */
1412 	uint32_t s_file_encryption_mode;
1413 	uint32_t s_dir_encryption_mode;
1414 #endif
1415 };
1416 
EXT4_SB(struct super_block * sb)1417 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1418 {
1419 	return sb->s_fs_info;
1420 }
EXT4_I(struct inode * inode)1421 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1422 {
1423 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1424 }
1425 
ext4_current_time(struct inode * inode)1426 static inline struct timespec ext4_current_time(struct inode *inode)
1427 {
1428 	return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1429 		current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1430 }
1431 
ext4_valid_inum(struct super_block * sb,unsigned long ino)1432 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1433 {
1434 	return ino == EXT4_ROOT_INO ||
1435 		ino == EXT4_USR_QUOTA_INO ||
1436 		ino == EXT4_GRP_QUOTA_INO ||
1437 		ino == EXT4_BOOT_LOADER_INO ||
1438 		ino == EXT4_JOURNAL_INO ||
1439 		ino == EXT4_RESIZE_INO ||
1440 		(ino >= EXT4_FIRST_INO(sb) &&
1441 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1442 }
1443 
ext4_set_io_unwritten_flag(struct inode * inode,struct ext4_io_end * io_end)1444 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1445 					      struct ext4_io_end *io_end)
1446 {
1447 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1448 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
1449 		atomic_inc(&EXT4_I(inode)->i_unwritten);
1450 	}
1451 }
1452 
ext4_inode_aio(struct inode * inode)1453 static inline ext4_io_end_t *ext4_inode_aio(struct inode *inode)
1454 {
1455 	return inode->i_private;
1456 }
1457 
ext4_inode_aio_set(struct inode * inode,ext4_io_end_t * io)1458 static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
1459 {
1460 	inode->i_private = io;
1461 }
1462 
1463 /*
1464  * Inode dynamic state flags
1465  */
1466 enum {
1467 	EXT4_STATE_JDATA,		/* journaled data exists */
1468 	EXT4_STATE_NEW,			/* inode is newly created */
1469 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1470 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1471 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1472 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1473 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1474 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1475 	EXT4_STATE_DIOREAD_LOCK,	/* Disable support for dio read
1476 					   nolocking */
1477 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1478 	EXT4_STATE_ORDERED_MODE,	/* data=ordered mode */
1479 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1480 };
1481 
1482 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1483 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1484 {									\
1485 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1486 }									\
1487 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1488 {									\
1489 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1490 }									\
1491 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1492 {									\
1493 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1494 }
1495 
1496 /* Add these declarations here only so that these functions can be
1497  * found by name.  Otherwise, they are very hard to locate. */
1498 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1499 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1500 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1501 EXT4_INODE_BIT_FNS(flag, flags, 0)
1502 
1503 /* Add these declarations here only so that these functions can be
1504  * found by name.  Otherwise, they are very hard to locate. */
1505 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1506 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1507 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1508 #if (BITS_PER_LONG < 64)
1509 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1510 
ext4_clear_state_flags(struct ext4_inode_info * ei)1511 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1512 {
1513 	(ei)->i_state_flags = 0;
1514 }
1515 #else
1516 EXT4_INODE_BIT_FNS(state, flags, 32)
1517 
ext4_clear_state_flags(struct ext4_inode_info * ei)1518 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1519 {
1520 	/* We depend on the fact that callers will set i_flags */
1521 }
1522 #endif
1523 #else
1524 /* Assume that user mode programs are passing in an ext4fs superblock, not
1525  * a kernel struct super_block.  This will allow us to call the feature-test
1526  * macros from user land. */
1527 #define EXT4_SB(sb)	(sb)
1528 #endif
1529 
1530 /*
1531  * Returns true if the inode is inode is encrypted
1532  */
ext4_encrypted_inode(struct inode * inode)1533 static inline int ext4_encrypted_inode(struct inode *inode)
1534 {
1535 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1536 	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
1537 #else
1538 	return 0;
1539 #endif
1540 }
1541 
1542 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1543 
1544 /*
1545  * Codes for operating systems
1546  */
1547 #define EXT4_OS_LINUX		0
1548 #define EXT4_OS_HURD		1
1549 #define EXT4_OS_MASIX		2
1550 #define EXT4_OS_FREEBSD		3
1551 #define EXT4_OS_LITES		4
1552 
1553 /*
1554  * Revision levels
1555  */
1556 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1557 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1558 
1559 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1560 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1561 
1562 #define EXT4_GOOD_OLD_INODE_SIZE 128
1563 
1564 /*
1565  * Feature set definitions
1566  */
1567 
1568 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)			\
1569 	((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1570 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)			\
1571 	((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1572 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)			\
1573 	((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1574 #define EXT4_SET_COMPAT_FEATURE(sb,mask)			\
1575 	EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1576 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)			\
1577 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1578 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)			\
1579 	EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1580 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)			\
1581 	EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1582 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
1583 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1584 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
1585 	EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1586 
1587 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1588 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1589 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1590 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1591 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1592 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1593 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1594 
1595 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1596 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1597 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1598 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1599 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1600 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1601 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1602 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1603 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1604 /*
1605  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1606  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1607  * all other data structures' checksums.  However, the METADATA_CSUM and
1608  * GDT_CSUM bits are mutually exclusive.
1609  */
1610 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1611 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1612 
1613 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1614 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1615 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1616 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1617 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1618 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1619 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1620 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1621 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1622 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1623 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1624 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM	0x2000 /* use crc32c for bg */
1625 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1626 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1627 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1628 
1629 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1630 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1631 					 EXT4_FEATURE_INCOMPAT_META_BG)
1632 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1633 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1634 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1635 
1636 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1637 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1638 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1639 					 EXT4_FEATURE_INCOMPAT_META_BG)
1640 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1641 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1642 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1643 
1644 #define EXT4_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR
1645 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1646 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1647 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1648 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1649 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1650 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1651 					 EXT4_FEATURE_INCOMPAT_MMP | \
1652 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1653 					 EXT4_FEATURE_INCOMPAT_ENCRYPT)
1654 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1655 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1656 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1657 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1658 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1659 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1660 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1661 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1662 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1663 					 EXT4_FEATURE_RO_COMPAT_QUOTA)
1664 
1665 /*
1666  * Default values for user and/or group using reserved blocks
1667  */
1668 #define	EXT4_DEF_RESUID		0
1669 #define	EXT4_DEF_RESGID		0
1670 
1671 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1672 
1673 /*
1674  * Default mount options
1675  */
1676 #define EXT4_DEFM_DEBUG		0x0001
1677 #define EXT4_DEFM_BSDGROUPS	0x0002
1678 #define EXT4_DEFM_XATTR_USER	0x0004
1679 #define EXT4_DEFM_ACL		0x0008
1680 #define EXT4_DEFM_UID16		0x0010
1681 #define EXT4_DEFM_JMODE		0x0060
1682 #define EXT4_DEFM_JMODE_DATA	0x0020
1683 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1684 #define EXT4_DEFM_JMODE_WBACK	0x0060
1685 #define EXT4_DEFM_NOBARRIER	0x0100
1686 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1687 #define EXT4_DEFM_DISCARD	0x0400
1688 #define EXT4_DEFM_NODELALLOC	0x0800
1689 
1690 /*
1691  * Default journal batch times
1692  */
1693 #define EXT4_DEF_MIN_BATCH_TIME	0
1694 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1695 
1696 /*
1697  * Minimum number of groups in a flexgroup before we separate out
1698  * directories into the first block group of a flexgroup
1699  */
1700 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1701 
1702 /*
1703  * Structure of a directory entry
1704  */
1705 #define EXT4_NAME_LEN 255
1706 
1707 struct ext4_dir_entry {
1708 	__le32	inode;			/* Inode number */
1709 	__le16	rec_len;		/* Directory entry length */
1710 	__le16	name_len;		/* Name length */
1711 	char	name[EXT4_NAME_LEN];	/* File name */
1712 };
1713 
1714 /*
1715  * The new version of the directory entry.  Since EXT4 structures are
1716  * stored in intel byte order, and the name_len field could never be
1717  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1718  * file_type field.
1719  */
1720 struct ext4_dir_entry_2 {
1721 	__le32	inode;			/* Inode number */
1722 	__le16	rec_len;		/* Directory entry length */
1723 	__u8	name_len;		/* Name length */
1724 	__u8	file_type;
1725 	char	name[EXT4_NAME_LEN];	/* File name */
1726 };
1727 
1728 /*
1729  * This is a bogus directory entry at the end of each leaf block that
1730  * records checksums.
1731  */
1732 struct ext4_dir_entry_tail {
1733 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1734 	__le16	det_rec_len;		/* 12 */
1735 	__u8	det_reserved_zero2;	/* Zero name length */
1736 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1737 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1738 };
1739 
1740 #define EXT4_DIRENT_TAIL(block, blocksize) \
1741 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1742 					((blocksize) - \
1743 					 sizeof(struct ext4_dir_entry_tail))))
1744 
1745 /*
1746  * Ext4 directory file types.  Only the low 3 bits are used.  The
1747  * other bits are reserved for now.
1748  */
1749 #define EXT4_FT_UNKNOWN		0
1750 #define EXT4_FT_REG_FILE	1
1751 #define EXT4_FT_DIR		2
1752 #define EXT4_FT_CHRDEV		3
1753 #define EXT4_FT_BLKDEV		4
1754 #define EXT4_FT_FIFO		5
1755 #define EXT4_FT_SOCK		6
1756 #define EXT4_FT_SYMLINK		7
1757 
1758 #define EXT4_FT_MAX		8
1759 
1760 #define EXT4_FT_DIR_CSUM	0xDE
1761 
1762 /*
1763  * EXT4_DIR_PAD defines the directory entries boundaries
1764  *
1765  * NOTE: It must be a multiple of 4
1766  */
1767 #define EXT4_DIR_PAD			4
1768 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1769 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1770 					 ~EXT4_DIR_ROUND)
1771 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1772 
1773 /*
1774  * If we ever get support for fs block sizes > page_size, we'll need
1775  * to remove the #if statements in the next two functions...
1776  */
1777 static inline unsigned int
ext4_rec_len_from_disk(__le16 dlen,unsigned blocksize)1778 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1779 {
1780 	unsigned len = le16_to_cpu(dlen);
1781 
1782 #if (PAGE_CACHE_SIZE >= 65536)
1783 	if (len == EXT4_MAX_REC_LEN || len == 0)
1784 		return blocksize;
1785 	return (len & 65532) | ((len & 3) << 16);
1786 #else
1787 	return len;
1788 #endif
1789 }
1790 
ext4_rec_len_to_disk(unsigned len,unsigned blocksize)1791 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1792 {
1793 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1794 		BUG();
1795 #if (PAGE_CACHE_SIZE >= 65536)
1796 	if (len < 65536)
1797 		return cpu_to_le16(len);
1798 	if (len == blocksize) {
1799 		if (blocksize == 65536)
1800 			return cpu_to_le16(EXT4_MAX_REC_LEN);
1801 		else
1802 			return cpu_to_le16(0);
1803 	}
1804 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1805 #else
1806 	return cpu_to_le16(len);
1807 #endif
1808 }
1809 
1810 /*
1811  * Hash Tree Directory indexing
1812  * (c) Daniel Phillips, 2001
1813  */
1814 
1815 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1816 				      EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1817 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1818 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1819 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1820 
1821 /* Legal values for the dx_root hash_version field: */
1822 
1823 #define DX_HASH_LEGACY		0
1824 #define DX_HASH_HALF_MD4	1
1825 #define DX_HASH_TEA		2
1826 #define DX_HASH_LEGACY_UNSIGNED	3
1827 #define DX_HASH_HALF_MD4_UNSIGNED	4
1828 #define DX_HASH_TEA_UNSIGNED		5
1829 
ext4_chksum(struct ext4_sb_info * sbi,u32 crc,const void * address,unsigned int length)1830 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1831 			      const void *address, unsigned int length)
1832 {
1833 	struct {
1834 		struct shash_desc shash;
1835 		char ctx[4];
1836 	} desc;
1837 	int err;
1838 
1839 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
1840 
1841 	desc.shash.tfm = sbi->s_chksum_driver;
1842 	desc.shash.flags = 0;
1843 	*(u32 *)desc.ctx = crc;
1844 
1845 	err = crypto_shash_update(&desc.shash, address, length);
1846 	BUG_ON(err);
1847 
1848 	return *(u32 *)desc.ctx;
1849 }
1850 
1851 #ifdef __KERNEL__
1852 
1853 /* hash info structure used by the directory hash */
1854 struct dx_hash_info
1855 {
1856 	u32		hash;
1857 	u32		minor_hash;
1858 	int		hash_version;
1859 	u32		*seed;
1860 };
1861 
1862 
1863 /* 32 and 64 bit signed EOF for dx directories */
1864 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1865 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1866 
1867 
1868 /*
1869  * Control parameters used by ext4_htree_next_block
1870  */
1871 #define HASH_NB_ALWAYS		1
1872 
1873 
1874 /*
1875  * Describe an inode's exact location on disk and in memory
1876  */
1877 struct ext4_iloc
1878 {
1879 	struct buffer_head *bh;
1880 	unsigned long offset;
1881 	ext4_group_t block_group;
1882 };
1883 
ext4_raw_inode(struct ext4_iloc * iloc)1884 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1885 {
1886 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1887 }
1888 
1889 /*
1890  * This structure is stuffed into the struct file's private_data field
1891  * for directories.  It is where we put information so that we can do
1892  * readdir operations in hash tree order.
1893  */
1894 struct dir_private_info {
1895 	struct rb_root	root;
1896 	struct rb_node	*curr_node;
1897 	struct fname	*extra_fname;
1898 	loff_t		last_pos;
1899 	__u32		curr_hash;
1900 	__u32		curr_minor_hash;
1901 	__u32		next_hash;
1902 };
1903 
1904 /* calculate the first block number of the group */
1905 static inline ext4_fsblk_t
ext4_group_first_block_no(struct super_block * sb,ext4_group_t group_no)1906 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1907 {
1908 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1909 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1910 }
1911 
1912 /*
1913  * Special error return code only used by dx_probe() and its callers.
1914  */
1915 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
1916 
1917 /*
1918  * Timeout and state flag for lazy initialization inode thread.
1919  */
1920 #define EXT4_DEF_LI_WAIT_MULT			10
1921 #define EXT4_DEF_LI_MAX_START_DELAY		5
1922 #define EXT4_LAZYINIT_QUIT			0x0001
1923 #define EXT4_LAZYINIT_RUNNING			0x0002
1924 
1925 /*
1926  * Lazy inode table initialization info
1927  */
1928 struct ext4_lazy_init {
1929 	unsigned long		li_state;
1930 	struct list_head	li_request_list;
1931 	struct mutex		li_list_mtx;
1932 };
1933 
1934 struct ext4_li_request {
1935 	struct super_block	*lr_super;
1936 	struct ext4_sb_info	*lr_sbi;
1937 	ext4_group_t		lr_next_group;
1938 	struct list_head	lr_request;
1939 	unsigned long		lr_next_sched;
1940 	unsigned long		lr_timeout;
1941 };
1942 
1943 struct ext4_features {
1944 	struct kobject f_kobj;
1945 	struct completion f_kobj_unregister;
1946 };
1947 
1948 /*
1949  * This structure will be used for multiple mount protection. It will be
1950  * written into the block number saved in the s_mmp_block field in the
1951  * superblock. Programs that check MMP should assume that if
1952  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1953  * to use the filesystem, regardless of how old the timestamp is.
1954  */
1955 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1956 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1957 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1958 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1959 
1960 struct mmp_struct {
1961 	__le32	mmp_magic;		/* Magic number for MMP */
1962 	__le32	mmp_seq;		/* Sequence no. updated periodically */
1963 
1964 	/*
1965 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1966 	 * purposes and do not affect the correctness of the algorithm
1967 	 */
1968 	__le64	mmp_time;		/* Time last updated */
1969 	char	mmp_nodename[64];	/* Node which last updated MMP block */
1970 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
1971 
1972 	/*
1973 	 * mmp_check_interval is used to verify if the MMP block has been
1974 	 * updated on the block device. The value is updated based on the
1975 	 * maximum time to write the MMP block during an update cycle.
1976 	 */
1977 	__le16	mmp_check_interval;
1978 
1979 	__le16	mmp_pad1;
1980 	__le32	mmp_pad2[226];
1981 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
1982 };
1983 
1984 /* arguments passed to the mmp thread */
1985 struct mmpd_data {
1986 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
1987 	struct super_block *sb;  /* super block of the fs */
1988 };
1989 
1990 /*
1991  * Check interval multiplier
1992  * The MMP block is written every update interval and initially checked every
1993  * update interval x the multiplier (the value is then adapted based on the
1994  * write latency). The reason is that writes can be delayed under load and we
1995  * don't want readers to incorrectly assume that the filesystem is no longer
1996  * in use.
1997  */
1998 #define EXT4_MMP_CHECK_MULT		2UL
1999 
2000 /*
2001  * Minimum interval for MMP checking in seconds.
2002  */
2003 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2004 
2005 /*
2006  * Maximum interval for MMP checking in seconds.
2007  */
2008 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2009 
2010 /*
2011  * Function prototypes
2012  */
2013 
2014 /*
2015  * Ok, these declarations are also in <linux/kernel.h> but none of the
2016  * ext4 source programs needs to include it so they are duplicated here.
2017  */
2018 # define NORET_TYPE	/**/
2019 # define ATTRIB_NORET	__attribute__((noreturn))
2020 # define NORET_AND	noreturn,
2021 
2022 /* bitmap.c */
2023 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2024 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2025 				struct ext4_group_desc *gdp,
2026 				struct buffer_head *bh, int sz);
2027 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2028 				  struct ext4_group_desc *gdp,
2029 				  struct buffer_head *bh, int sz);
2030 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2031 				struct ext4_group_desc *gdp,
2032 				struct buffer_head *bh);
2033 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2034 				  struct ext4_group_desc *gdp,
2035 				  struct buffer_head *bh);
2036 
2037 /* balloc.c */
2038 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2039 					 ext4_fsblk_t blocknr,
2040 					 ext4_group_t *blockgrpp,
2041 					 ext4_grpblk_t *offsetp);
2042 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2043 					  ext4_fsblk_t block);
2044 
2045 extern unsigned int ext4_block_group(struct super_block *sb,
2046 			ext4_fsblk_t blocknr);
2047 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2048 			ext4_fsblk_t blocknr);
2049 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2050 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2051 			ext4_group_t group);
2052 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2053 					 ext4_fsblk_t goal,
2054 					 unsigned int flags,
2055 					 unsigned long *count,
2056 					 int *errp);
2057 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2058 				    s64 nclusters, unsigned int flags);
2059 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2060 extern void ext4_check_blocks_bitmap(struct super_block *);
2061 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2062 						    ext4_group_t block_group,
2063 						    struct buffer_head ** bh);
2064 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2065 
2066 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2067 						ext4_group_t block_group);
2068 extern int ext4_wait_block_bitmap(struct super_block *sb,
2069 				  ext4_group_t block_group,
2070 				  struct buffer_head *bh);
2071 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2072 						  ext4_group_t block_group);
2073 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2074 					      ext4_group_t block_group,
2075 					      struct ext4_group_desc *gdp);
2076 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2077 
2078 /* crypto_policy.c */
2079 int ext4_is_child_context_consistent_with_parent(struct inode *parent,
2080 						 struct inode *child);
2081 int ext4_inherit_context(struct inode *parent, struct inode *child);
2082 void ext4_to_hex(char *dst, char *src, size_t src_size);
2083 int ext4_process_policy(const struct ext4_encryption_policy *policy,
2084 			struct inode *inode);
2085 int ext4_get_policy(struct inode *inode,
2086 		    struct ext4_encryption_policy *policy);
2087 
2088 /* crypto.c */
2089 bool ext4_valid_contents_enc_mode(uint32_t mode);
2090 uint32_t ext4_validate_encryption_key_size(uint32_t mode, uint32_t size);
2091 extern struct workqueue_struct *ext4_read_workqueue;
2092 struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode);
2093 void ext4_release_crypto_ctx(struct ext4_crypto_ctx *ctx);
2094 void ext4_restore_control_page(struct page *data_page);
2095 struct page *ext4_encrypt(struct inode *inode,
2096 			  struct page *plaintext_page);
2097 int ext4_decrypt(struct ext4_crypto_ctx *ctx, struct page *page);
2098 int ext4_decrypt_one(struct inode *inode, struct page *page);
2099 int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex);
2100 
2101 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2102 int ext4_init_crypto(void);
2103 void ext4_exit_crypto(void);
ext4_sb_has_crypto(struct super_block * sb)2104 static inline int ext4_sb_has_crypto(struct super_block *sb)
2105 {
2106 	return EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT);
2107 }
2108 #else
ext4_init_crypto(void)2109 static inline int ext4_init_crypto(void) { return 0; }
ext4_exit_crypto(void)2110 static inline void ext4_exit_crypto(void) { }
ext4_sb_has_crypto(struct super_block * sb)2111 static inline int ext4_sb_has_crypto(struct super_block *sb)
2112 {
2113 	return 0;
2114 }
2115 #endif
2116 
2117 /* crypto_fname.c */
2118 bool ext4_valid_filenames_enc_mode(uint32_t mode);
2119 u32 ext4_fname_crypto_round_up(u32 size, u32 blksize);
2120 int ext4_fname_crypto_alloc_buffer(struct ext4_fname_crypto_ctx *ctx,
2121 				   u32 ilen, struct ext4_str *crypto_str);
2122 int _ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
2123 			    struct dx_hash_info *hinfo,
2124 			    const struct ext4_str *iname,
2125 			    struct ext4_str *oname);
2126 int ext4_fname_disk_to_usr(struct ext4_fname_crypto_ctx *ctx,
2127 			   struct dx_hash_info *hinfo,
2128 			   const struct ext4_dir_entry_2 *de,
2129 			   struct ext4_str *oname);
2130 int ext4_fname_usr_to_disk(struct ext4_fname_crypto_ctx *ctx,
2131 			   const struct qstr *iname,
2132 			   struct ext4_str *oname);
2133 int ext4_fname_usr_to_hash(struct ext4_fname_crypto_ctx *ctx,
2134 			   const struct qstr *iname,
2135 			   struct dx_hash_info *hinfo);
2136 int ext4_fname_crypto_namelen_on_disk(struct ext4_fname_crypto_ctx *ctx,
2137 				      u32 namelen);
2138 int ext4_fname_match(struct ext4_fname_crypto_ctx *ctx, struct ext4_str *cstr,
2139 		     int len, const char * const name,
2140 		     struct ext4_dir_entry_2 *de);
2141 
2142 
2143 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2144 void ext4_put_fname_crypto_ctx(struct ext4_fname_crypto_ctx **ctx);
2145 struct ext4_fname_crypto_ctx *ext4_get_fname_crypto_ctx(struct inode *inode,
2146 							u32 max_len);
2147 void ext4_fname_crypto_free_buffer(struct ext4_str *crypto_str);
2148 #else
2149 static inline
ext4_put_fname_crypto_ctx(struct ext4_fname_crypto_ctx ** ctx)2150 void ext4_put_fname_crypto_ctx(struct ext4_fname_crypto_ctx **ctx) { }
2151 static inline
ext4_get_fname_crypto_ctx(struct inode * inode,u32 max_len)2152 struct ext4_fname_crypto_ctx *ext4_get_fname_crypto_ctx(struct inode *inode,
2153 							u32 max_len)
2154 {
2155 	return NULL;
2156 }
ext4_fname_crypto_free_buffer(struct ext4_str * p)2157 static inline void ext4_fname_crypto_free_buffer(struct ext4_str *p) { }
2158 #endif
2159 
2160 
2161 /* crypto_key.c */
2162 int ext4_generate_encryption_key(struct inode *inode);
2163 
2164 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2165 int ext4_has_encryption_key(struct inode *inode);
2166 #else
ext4_has_encryption_key(struct inode * inode)2167 static inline int ext4_has_encryption_key(struct inode *inode)
2168 {
2169 	return 0;
2170 }
2171 #endif
2172 
2173 
2174 /* dir.c */
2175 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2176 				  struct file *,
2177 				  struct ext4_dir_entry_2 *,
2178 				  struct buffer_head *, char *, int,
2179 				  unsigned int);
2180 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2181 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2182 					(de), (bh), (buf), (size), (offset)))
2183 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2184 				__u32 minor_hash,
2185 				struct ext4_dir_entry_2 *dirent,
2186 				struct ext4_str *ent_name);
2187 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2188 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2189 			     struct buffer_head *bh,
2190 			     void *buf, int buf_size,
2191 			     const char *name, int namelen,
2192 			     struct ext4_dir_entry_2 **dest_de);
2193 int ext4_insert_dentry(struct inode *dir,
2194 			struct inode *inode,
2195 			struct ext4_dir_entry_2 *de,
2196 			int buf_size,
2197 		       const struct qstr *iname,
2198 			const char *name, int namelen);
ext4_update_dx_flag(struct inode * inode)2199 static inline void ext4_update_dx_flag(struct inode *inode)
2200 {
2201 	if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
2202 				     EXT4_FEATURE_COMPAT_DIR_INDEX))
2203 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2204 }
2205 static unsigned char ext4_filetype_table[] = {
2206 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2207 };
2208 
get_dtype(struct super_block * sb,int filetype)2209 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2210 {
2211 	if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) ||
2212 	    (filetype >= EXT4_FT_MAX))
2213 		return DT_UNKNOWN;
2214 
2215 	return ext4_filetype_table[filetype];
2216 }
2217 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2218 			     void *buf, int buf_size);
2219 
2220 /* fsync.c */
2221 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2222 
2223 /* hash.c */
2224 extern int ext4fs_dirhash(const char *name, int len, struct
2225 			  dx_hash_info *hinfo);
2226 
2227 /* ialloc.c */
2228 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2229 				      const struct qstr *qstr, __u32 goal,
2230 				      uid_t *owner, int handle_type,
2231 				      unsigned int line_no, int nblocks);
2232 
2233 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner) \
2234 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2235 			 0, 0, 0)
2236 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2237 				    type, nblocks)		    \
2238 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2239 			 (type), __LINE__, (nblocks))
2240 
2241 
2242 extern void ext4_free_inode(handle_t *, struct inode *);
2243 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2244 extern unsigned long ext4_count_free_inodes(struct super_block *);
2245 extern unsigned long ext4_count_dirs(struct super_block *);
2246 extern void ext4_check_inodes_bitmap(struct super_block *);
2247 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2248 extern int ext4_init_inode_table(struct super_block *sb,
2249 				 ext4_group_t group, int barrier);
2250 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2251 
2252 /* mballoc.c */
2253 extern long ext4_mb_stats;
2254 extern long ext4_mb_max_to_scan;
2255 extern int ext4_mb_init(struct super_block *);
2256 extern int ext4_mb_release(struct super_block *);
2257 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2258 				struct ext4_allocation_request *, int *);
2259 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2260 extern void ext4_discard_preallocations(struct inode *);
2261 extern int __init ext4_init_mballoc(void);
2262 extern void ext4_exit_mballoc(void);
2263 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2264 			     struct buffer_head *bh, ext4_fsblk_t block,
2265 			     unsigned long count, int flags);
2266 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2267 				   ext4_group_t ngroups);
2268 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2269 		ext4_group_t i, struct ext4_group_desc *desc);
2270 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2271 				ext4_fsblk_t block, unsigned long count);
2272 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2273 
2274 /* inode.c */
2275 int ext4_inode_is_fast_symlink(struct inode *inode);
2276 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2277 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2278 int ext4_get_block_write(struct inode *inode, sector_t iblock,
2279 			 struct buffer_head *bh_result, int create);
2280 int ext4_get_block(struct inode *inode, sector_t iblock,
2281 				struct buffer_head *bh_result, int create);
2282 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2283 			   struct buffer_head *bh, int create);
2284 int ext4_walk_page_buffers(handle_t *handle,
2285 			   struct buffer_head *head,
2286 			   unsigned from,
2287 			   unsigned to,
2288 			   int *partial,
2289 			   int (*fn)(handle_t *handle,
2290 				     struct buffer_head *bh));
2291 int do_journal_get_write_access(handle_t *handle,
2292 				struct buffer_head *bh);
2293 #define FALL_BACK_TO_NONDELALLOC 1
2294 #define CONVERT_INLINE_DATA	 2
2295 
2296 extern struct inode *ext4_iget(struct super_block *, unsigned long);
2297 extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
2298 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2299 extern int  ext4_setattr(struct dentry *, struct iattr *);
2300 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2301 				struct kstat *stat);
2302 extern void ext4_evict_inode(struct inode *);
2303 extern void ext4_clear_inode(struct inode *);
2304 extern int  ext4_sync_inode(handle_t *, struct inode *);
2305 extern void ext4_dirty_inode(struct inode *, int);
2306 extern int ext4_change_inode_journal_flag(struct inode *, int);
2307 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2308 extern int ext4_inode_attach_jinode(struct inode *inode);
2309 extern int ext4_can_truncate(struct inode *inode);
2310 extern void ext4_truncate(struct inode *);
2311 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2312 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2313 extern void ext4_set_inode_flags(struct inode *);
2314 extern void ext4_get_inode_flags(struct ext4_inode_info *);
2315 extern int ext4_alloc_da_blocks(struct inode *inode);
2316 extern void ext4_set_aops(struct inode *inode);
2317 extern int ext4_writepage_trans_blocks(struct inode *);
2318 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2319 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2320 			     loff_t lstart, loff_t lend);
2321 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2322 extern int ext4_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf);
2323 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2324 extern void ext4_da_update_reserve_space(struct inode *inode,
2325 					int used, int quota_claim);
2326 
2327 /* indirect.c */
2328 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2329 				struct ext4_map_blocks *map, int flags);
2330 extern ssize_t ext4_ind_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
2331 				  loff_t offset);
2332 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2333 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2334 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2335 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2336 				 ext4_lblk_t start, ext4_lblk_t end);
2337 
2338 /* ioctl.c */
2339 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2340 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2341 
2342 /* migrate.c */
2343 extern int ext4_ext_migrate(struct inode *);
2344 extern int ext4_ind_migrate(struct inode *inode);
2345 
2346 /* namei.c */
2347 extern int ext4_dirent_csum_verify(struct inode *inode,
2348 				   struct ext4_dir_entry *dirent);
2349 extern int ext4_orphan_add(handle_t *, struct inode *);
2350 extern int ext4_orphan_del(handle_t *, struct inode *);
2351 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2352 				__u32 start_minor_hash, __u32 *next_hash);
2353 extern int search_dir(struct buffer_head *bh,
2354 		      char *search_buf,
2355 		      int buf_size,
2356 		      struct inode *dir,
2357 		      const struct qstr *d_name,
2358 		      unsigned int offset,
2359 		      struct ext4_dir_entry_2 **res_dir);
2360 extern int ext4_generic_delete_entry(handle_t *handle,
2361 				     struct inode *dir,
2362 				     struct ext4_dir_entry_2 *de_del,
2363 				     struct buffer_head *bh,
2364 				     void *entry_buf,
2365 				     int buf_size,
2366 				     int csum_size);
2367 extern int ext4_empty_dir(struct inode *inode);
2368 
2369 /* resize.c */
2370 extern int ext4_group_add(struct super_block *sb,
2371 				struct ext4_new_group_data *input);
2372 extern int ext4_group_extend(struct super_block *sb,
2373 				struct ext4_super_block *es,
2374 				ext4_fsblk_t n_blocks_count);
2375 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2376 
2377 /* super.c */
2378 extern int ext4_calculate_overhead(struct super_block *sb);
2379 extern void ext4_superblock_csum_set(struct super_block *sb);
2380 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2381 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2382 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2383 				    ext4_group_t ngroup);
2384 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2385 				     char nbuf[16]);
2386 
2387 extern __printf(4, 5)
2388 void __ext4_error(struct super_block *, const char *, unsigned int,
2389 		  const char *, ...);
2390 extern __printf(5, 6)
2391 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2392 		      const char *, ...);
2393 extern __printf(5, 6)
2394 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2395 		     const char *, ...);
2396 extern void __ext4_std_error(struct super_block *, const char *,
2397 			     unsigned int, int);
2398 extern __printf(4, 5)
2399 void __ext4_abort(struct super_block *, const char *, unsigned int,
2400 		  const char *, ...);
2401 extern __printf(4, 5)
2402 void __ext4_warning(struct super_block *, const char *, unsigned int,
2403 		    const char *, ...);
2404 extern __printf(3, 4)
2405 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2406 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2407 			   const char *, unsigned int, const char *);
2408 extern __printf(7, 8)
2409 void __ext4_grp_locked_error(const char *, unsigned int,
2410 			     struct super_block *, ext4_group_t,
2411 			     unsigned long, ext4_fsblk_t,
2412 			     const char *, ...);
2413 
2414 #ifdef CONFIG_PRINTK
2415 
2416 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2417 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2418 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2419 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2420 #define ext4_error(sb, fmt, ...)					\
2421 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2422 #define ext4_abort(sb, fmt, ...)					\
2423 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2424 #define ext4_warning(sb, fmt, ...)					\
2425 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2426 #define ext4_msg(sb, level, fmt, ...)				\
2427 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2428 #define dump_mmp_msg(sb, mmp, msg)					\
2429 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2430 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2431 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2432 				fmt, ##__VA_ARGS__)
2433 
2434 #else
2435 
2436 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2437 do {									\
2438 	no_printk(fmt, ##__VA_ARGS__);					\
2439 	__ext4_error_inode(inode, "", 0, block, " ");			\
2440 } while (0)
2441 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2442 do {									\
2443 	no_printk(fmt, ##__VA_ARGS__);					\
2444 	__ext4_error_file(file, "", 0, block, " ");			\
2445 } while (0)
2446 #define ext4_error(sb, fmt, ...)					\
2447 do {									\
2448 	no_printk(fmt, ##__VA_ARGS__);					\
2449 	__ext4_error(sb, "", 0, " ");					\
2450 } while (0)
2451 #define ext4_abort(sb, fmt, ...)					\
2452 do {									\
2453 	no_printk(fmt, ##__VA_ARGS__);					\
2454 	__ext4_abort(sb, "", 0, " ");					\
2455 } while (0)
2456 #define ext4_warning(sb, fmt, ...)					\
2457 do {									\
2458 	no_printk(fmt, ##__VA_ARGS__);					\
2459 	__ext4_warning(sb, "", 0, " ");					\
2460 } while (0)
2461 #define ext4_msg(sb, level, fmt, ...)					\
2462 do {									\
2463 	no_printk(fmt, ##__VA_ARGS__);					\
2464 	__ext4_msg(sb, "", " ");					\
2465 } while (0)
2466 #define dump_mmp_msg(sb, mmp, msg)					\
2467 	__dump_mmp_msg(sb, mmp, "", 0, "")
2468 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2469 do {									\
2470 	no_printk(fmt, ##__VA_ARGS__);				\
2471 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2472 } while (0)
2473 
2474 #endif
2475 
2476 extern void ext4_update_dynamic_rev(struct super_block *sb);
2477 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2478 					__u32 compat);
2479 extern int ext4_update_rocompat_feature(handle_t *handle,
2480 					struct super_block *sb,	__u32 rocompat);
2481 extern int ext4_update_incompat_feature(handle_t *handle,
2482 					struct super_block *sb,	__u32 incompat);
2483 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2484 				      struct ext4_group_desc *bg);
2485 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2486 				      struct ext4_group_desc *bg);
2487 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2488 				     struct ext4_group_desc *bg);
2489 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2490 				      struct ext4_group_desc *bg);
2491 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2492 				 struct ext4_group_desc *bg);
2493 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2494 				struct ext4_group_desc *bg);
2495 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2496 				   struct ext4_group_desc *bg);
2497 extern void ext4_block_bitmap_set(struct super_block *sb,
2498 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2499 extern void ext4_inode_bitmap_set(struct super_block *sb,
2500 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2501 extern void ext4_inode_table_set(struct super_block *sb,
2502 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2503 extern void ext4_free_group_clusters_set(struct super_block *sb,
2504 					 struct ext4_group_desc *bg,
2505 					 __u32 count);
2506 extern void ext4_free_inodes_set(struct super_block *sb,
2507 				struct ext4_group_desc *bg, __u32 count);
2508 extern void ext4_used_dirs_set(struct super_block *sb,
2509 				struct ext4_group_desc *bg, __u32 count);
2510 extern void ext4_itable_unused_set(struct super_block *sb,
2511 				   struct ext4_group_desc *bg, __u32 count);
2512 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2513 				       struct ext4_group_desc *gdp);
2514 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2515 				     struct ext4_group_desc *gdp);
2516 extern int ext4_register_li_request(struct super_block *sb,
2517 				    ext4_group_t first_not_zeroed);
2518 
ext4_has_group_desc_csum(struct super_block * sb)2519 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2520 {
2521 	return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2522 					  EXT4_FEATURE_RO_COMPAT_GDT_CSUM) ||
2523 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
2524 }
2525 
ext4_has_metadata_csum(struct super_block * sb)2526 static inline int ext4_has_metadata_csum(struct super_block *sb)
2527 {
2528 	WARN_ON_ONCE(EXT4_HAS_RO_COMPAT_FEATURE(sb,
2529 			EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
2530 		     !EXT4_SB(sb)->s_chksum_driver);
2531 
2532 	return (EXT4_SB(sb)->s_chksum_driver != NULL);
2533 }
ext4_blocks_count(struct ext4_super_block * es)2534 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2535 {
2536 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2537 		le32_to_cpu(es->s_blocks_count_lo);
2538 }
2539 
ext4_r_blocks_count(struct ext4_super_block * es)2540 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2541 {
2542 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2543 		le32_to_cpu(es->s_r_blocks_count_lo);
2544 }
2545 
ext4_free_blocks_count(struct ext4_super_block * es)2546 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2547 {
2548 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2549 		le32_to_cpu(es->s_free_blocks_count_lo);
2550 }
2551 
ext4_blocks_count_set(struct ext4_super_block * es,ext4_fsblk_t blk)2552 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2553 					 ext4_fsblk_t blk)
2554 {
2555 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2556 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2557 }
2558 
ext4_free_blocks_count_set(struct ext4_super_block * es,ext4_fsblk_t blk)2559 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2560 					      ext4_fsblk_t blk)
2561 {
2562 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2563 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2564 }
2565 
ext4_r_blocks_count_set(struct ext4_super_block * es,ext4_fsblk_t blk)2566 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2567 					   ext4_fsblk_t blk)
2568 {
2569 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2570 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2571 }
2572 
ext4_isize(struct ext4_inode * raw_inode)2573 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2574 {
2575 	if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2576 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2577 			le32_to_cpu(raw_inode->i_size_lo);
2578 	else
2579 		return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2580 }
2581 
ext4_isize_set(struct ext4_inode * raw_inode,loff_t i_size)2582 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2583 {
2584 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2585 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2586 }
2587 
2588 static inline
ext4_get_group_info(struct super_block * sb,ext4_group_t group)2589 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2590 					    ext4_group_t group)
2591 {
2592 	 struct ext4_group_info ***grp_info;
2593 	 long indexv, indexh;
2594 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2595 	 grp_info = EXT4_SB(sb)->s_group_info;
2596 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2597 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2598 	 return grp_info[indexv][indexh];
2599 }
2600 
2601 /*
2602  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2603  * the locking protocol documented in the comments of ext4_group_add()
2604  * in resize.c
2605  */
ext4_get_groups_count(struct super_block * sb)2606 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2607 {
2608 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2609 
2610 	smp_rmb();
2611 	return ngroups;
2612 }
2613 
ext4_flex_group(struct ext4_sb_info * sbi,ext4_group_t block_group)2614 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2615 					     ext4_group_t block_group)
2616 {
2617 	return block_group >> sbi->s_log_groups_per_flex;
2618 }
2619 
ext4_flex_bg_size(struct ext4_sb_info * sbi)2620 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2621 {
2622 	return 1 << sbi->s_log_groups_per_flex;
2623 }
2624 
2625 #define ext4_std_error(sb, errno)				\
2626 do {								\
2627 	if ((errno))						\
2628 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2629 } while (0)
2630 
2631 #ifdef CONFIG_SMP
2632 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2633  * counters. So we need to make sure we have free clusters more
2634  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2635  */
2636 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2637 #else
2638 #define EXT4_FREECLUSTERS_WATERMARK 0
2639 #endif
2640 
2641 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
ext4_update_i_disksize(struct inode * inode,loff_t newsize)2642 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2643 {
2644 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2645 		     !mutex_is_locked(&inode->i_mutex));
2646 	down_write(&EXT4_I(inode)->i_data_sem);
2647 	if (newsize > EXT4_I(inode)->i_disksize)
2648 		EXT4_I(inode)->i_disksize = newsize;
2649 	up_write(&EXT4_I(inode)->i_data_sem);
2650 }
2651 
2652 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
ext4_update_inode_size(struct inode * inode,loff_t newsize)2653 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2654 {
2655 	int changed = 0;
2656 
2657 	if (newsize > inode->i_size) {
2658 		i_size_write(inode, newsize);
2659 		changed = 1;
2660 	}
2661 	if (newsize > EXT4_I(inode)->i_disksize) {
2662 		ext4_update_i_disksize(inode, newsize);
2663 		changed |= 2;
2664 	}
2665 	return changed;
2666 }
2667 
2668 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2669 				      loff_t len);
2670 
2671 struct ext4_group_info {
2672 	unsigned long   bb_state;
2673 	struct rb_root  bb_free_root;
2674 	ext4_grpblk_t	bb_first_free;	/* first free block */
2675 	ext4_grpblk_t	bb_free;	/* total free blocks */
2676 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2677 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2678 	struct          list_head bb_prealloc_list;
2679 #ifdef DOUBLE_CHECK
2680 	void            *bb_bitmap;
2681 #endif
2682 	struct rw_semaphore alloc_sem;
2683 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2684 					 * regions, index is order.
2685 					 * bb_counters[3] = 5 means
2686 					 * 5 free 8-block regions. */
2687 };
2688 
2689 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2690 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2691 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2692 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2693 
2694 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2695 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2696 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2697 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2698 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2699 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2700 
2701 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2702 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2703 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2704 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2705 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2706 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2707 
2708 #define EXT4_MAX_CONTENTION		8
2709 #define EXT4_CONTENTION_THRESHOLD	2
2710 
ext4_group_lock_ptr(struct super_block * sb,ext4_group_t group)2711 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2712 					      ext4_group_t group)
2713 {
2714 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2715 }
2716 
2717 /*
2718  * Returns true if the filesystem is busy enough that attempts to
2719  * access the block group locks has run into contention.
2720  */
ext4_fs_is_busy(struct ext4_sb_info * sbi)2721 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2722 {
2723 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2724 }
2725 
ext4_lock_group(struct super_block * sb,ext4_group_t group)2726 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2727 {
2728 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2729 	if (spin_trylock(lock))
2730 		/*
2731 		 * We're able to grab the lock right away, so drop the
2732 		 * lock contention counter.
2733 		 */
2734 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2735 	else {
2736 		/*
2737 		 * The lock is busy, so bump the contention counter,
2738 		 * and then wait on the spin lock.
2739 		 */
2740 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2741 				  EXT4_MAX_CONTENTION);
2742 		spin_lock(lock);
2743 	}
2744 }
2745 
ext4_unlock_group(struct super_block * sb,ext4_group_t group)2746 static inline void ext4_unlock_group(struct super_block *sb,
2747 					ext4_group_t group)
2748 {
2749 	spin_unlock(ext4_group_lock_ptr(sb, group));
2750 }
2751 
2752 /*
2753  * Block validity checking
2754  */
2755 #define ext4_check_indirect_blockref(inode, bh)				\
2756 	ext4_check_blockref(__func__, __LINE__, inode,			\
2757 			    (__le32 *)(bh)->b_data,			\
2758 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2759 
2760 #define ext4_ind_check_inode(inode)					\
2761 	ext4_check_blockref(__func__, __LINE__, inode,			\
2762 			    EXT4_I(inode)->i_data,			\
2763 			    EXT4_NDIR_BLOCKS)
2764 
2765 /*
2766  * Inodes and files operations
2767  */
2768 
2769 /* dir.c */
2770 extern const struct file_operations ext4_dir_operations;
2771 
2772 /* file.c */
2773 extern const struct inode_operations ext4_file_inode_operations;
2774 extern const struct file_operations ext4_file_operations;
2775 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2776 
2777 /* inline.c */
2778 extern int ext4_get_max_inline_size(struct inode *inode);
2779 extern int ext4_find_inline_data_nolock(struct inode *inode);
2780 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2781 				 unsigned int len);
2782 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2783 
2784 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2785 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2786 					 struct inode *inode,
2787 					 loff_t pos, unsigned len,
2788 					 unsigned flags,
2789 					 struct page **pagep);
2790 extern int ext4_write_inline_data_end(struct inode *inode,
2791 				      loff_t pos, unsigned len,
2792 				      unsigned copied,
2793 				      struct page *page);
2794 extern struct buffer_head *
2795 ext4_journalled_write_inline_data(struct inode *inode,
2796 				  unsigned len,
2797 				  struct page *page);
2798 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
2799 					   struct inode *inode,
2800 					   loff_t pos, unsigned len,
2801 					   unsigned flags,
2802 					   struct page **pagep,
2803 					   void **fsdata);
2804 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
2805 					 unsigned len, unsigned copied,
2806 					 struct page *page);
2807 extern int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry,
2808 				     struct inode *inode);
2809 extern int ext4_try_create_inline_dir(handle_t *handle,
2810 				      struct inode *parent,
2811 				      struct inode *inode);
2812 extern int ext4_read_inline_dir(struct file *filp,
2813 				struct dir_context *ctx,
2814 				int *has_inline_data);
2815 extern int htree_inlinedir_to_tree(struct file *dir_file,
2816 				   struct inode *dir, ext4_lblk_t block,
2817 				   struct dx_hash_info *hinfo,
2818 				   __u32 start_hash, __u32 start_minor_hash,
2819 				   int *has_inline_data);
2820 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
2821 					const struct qstr *d_name,
2822 					struct ext4_dir_entry_2 **res_dir,
2823 					int *has_inline_data);
2824 extern int ext4_delete_inline_entry(handle_t *handle,
2825 				    struct inode *dir,
2826 				    struct ext4_dir_entry_2 *de_del,
2827 				    struct buffer_head *bh,
2828 				    int *has_inline_data);
2829 extern int empty_inline_dir(struct inode *dir, int *has_inline_data);
2830 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
2831 					struct ext4_dir_entry_2 **parent_de,
2832 					int *retval);
2833 extern int ext4_inline_data_fiemap(struct inode *inode,
2834 				   struct fiemap_extent_info *fieinfo,
2835 				   int *has_inline, __u64 start, __u64 len);
2836 extern int ext4_try_to_evict_inline_data(handle_t *handle,
2837 					 struct inode *inode,
2838 					 int needed);
2839 extern void ext4_inline_data_truncate(struct inode *inode, int *has_inline);
2840 
2841 extern int ext4_convert_inline_data(struct inode *inode);
2842 
ext4_has_inline_data(struct inode * inode)2843 static inline int ext4_has_inline_data(struct inode *inode)
2844 {
2845 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
2846 	       EXT4_I(inode)->i_inline_off;
2847 }
2848 
2849 /* namei.c */
2850 extern const struct inode_operations ext4_dir_inode_operations;
2851 extern const struct inode_operations ext4_special_inode_operations;
2852 extern struct dentry *ext4_get_parent(struct dentry *child);
2853 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2854 				 struct ext4_dir_entry_2 *de,
2855 				 int blocksize, int csum_size,
2856 				 unsigned int parent_ino, int dotdot_real_len);
2857 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
2858 				   unsigned int blocksize);
2859 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
2860 					 struct inode *inode,
2861 					 struct buffer_head *bh);
2862 #define S_SHIFT 12
2863 static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
2864 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
2865 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
2866 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
2867 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
2868 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
2869 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
2870 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
2871 };
2872 
ext4_set_de_type(struct super_block * sb,struct ext4_dir_entry_2 * de,umode_t mode)2873 static inline void ext4_set_de_type(struct super_block *sb,
2874 				struct ext4_dir_entry_2 *de,
2875 				umode_t mode) {
2876 	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE))
2877 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
2878 }
2879 
2880 /* readpages.c */
2881 extern int ext4_mpage_readpages(struct address_space *mapping,
2882 				struct list_head *pages, struct page *page,
2883 				unsigned nr_pages);
2884 
2885 /* symlink.c */
2886 extern const struct inode_operations ext4_symlink_inode_operations;
2887 extern const struct inode_operations ext4_fast_symlink_inode_operations;
2888 
2889 /* block_validity */
2890 extern void ext4_release_system_zone(struct super_block *sb);
2891 extern int ext4_setup_system_zone(struct super_block *sb);
2892 extern int __init ext4_init_system_zone(void);
2893 extern void ext4_exit_system_zone(void);
2894 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2895 				 ext4_fsblk_t start_blk,
2896 				 unsigned int count);
2897 extern int ext4_check_blockref(const char *, unsigned int,
2898 			       struct inode *, __le32 *, unsigned int);
2899 
2900 /* extents.c */
2901 struct ext4_ext_path;
2902 struct ext4_extent;
2903 
2904 /*
2905  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
2906  * __le32.
2907  */
2908 #define EXT_MAX_BLOCKS	0xffffffff
2909 
2910 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2911 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2912 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
2913 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2914 			       struct ext4_map_blocks *map, int flags);
2915 extern void ext4_ext_truncate(handle_t *, struct inode *);
2916 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
2917 				 ext4_lblk_t end);
2918 extern void ext4_ext_init(struct super_block *);
2919 extern void ext4_ext_release(struct super_block *);
2920 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2921 			  loff_t len);
2922 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
2923 					  loff_t offset, ssize_t len);
2924 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2925 			   struct ext4_map_blocks *map, int flags);
2926 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
2927 					 ext4_lblk_t lblocks);
2928 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
2929 						   int num,
2930 						   struct ext4_ext_path *path);
2931 extern int ext4_can_extents_be_merged(struct inode *inode,
2932 				      struct ext4_extent *ex1,
2933 				      struct ext4_extent *ex2);
2934 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
2935 				  struct ext4_ext_path **,
2936 				  struct ext4_extent *, int);
2937 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
2938 					      struct ext4_ext_path **,
2939 					      int flags);
2940 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
2941 extern int ext4_ext_check_inode(struct inode *inode);
2942 extern int ext4_find_delalloc_range(struct inode *inode,
2943 				    ext4_lblk_t lblk_start,
2944 				    ext4_lblk_t lblk_end);
2945 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
2946 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
2947 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2948 			__u64 start, __u64 len);
2949 extern int ext4_ext_precache(struct inode *inode);
2950 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
2951 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
2952 				struct inode *inode2, ext4_lblk_t lblk1,
2953 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
2954 			     int mark_unwritten,int *err);
2955 
2956 /* move_extent.c */
2957 extern void ext4_double_down_write_data_sem(struct inode *first,
2958 					    struct inode *second);
2959 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
2960 					  struct inode *donor_inode);
2961 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2962 			     __u64 start_orig, __u64 start_donor,
2963 			     __u64 len, __u64 *moved_len);
2964 
2965 /* page-io.c */
2966 extern int __init ext4_init_pageio(void);
2967 extern void ext4_exit_pageio(void);
2968 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2969 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
2970 extern int ext4_put_io_end(ext4_io_end_t *io_end);
2971 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
2972 extern void ext4_io_submit_init(struct ext4_io_submit *io,
2973 				struct writeback_control *wbc);
2974 extern void ext4_end_io_rsv_work(struct work_struct *work);
2975 extern void ext4_io_submit(struct ext4_io_submit *io);
2976 extern int ext4_bio_write_page(struct ext4_io_submit *io,
2977 			       struct page *page,
2978 			       int len,
2979 			       struct writeback_control *wbc,
2980 			       bool keep_towrite);
2981 
2982 /* mmp.c */
2983 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2984 
2985 /*
2986  * Add new method to test whether block and inode bitmaps are properly
2987  * initialized. With uninit_bg reading the block from disk is not enough
2988  * to mark the bitmap uptodate. We need to also zero-out the bitmap
2989  */
2990 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2991 
bitmap_uptodate(struct buffer_head * bh)2992 static inline int bitmap_uptodate(struct buffer_head *bh)
2993 {
2994 	return (buffer_uptodate(bh) &&
2995 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2996 }
set_bitmap_uptodate(struct buffer_head * bh)2997 static inline void set_bitmap_uptodate(struct buffer_head *bh)
2998 {
2999 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3000 }
3001 
3002 /*
3003  * Disable DIO read nolock optimization, so new dioreaders will be forced
3004  * to grab i_mutex
3005  */
ext4_inode_block_unlocked_dio(struct inode * inode)3006 static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
3007 {
3008 	ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3009 	smp_mb();
3010 }
ext4_inode_resume_unlocked_dio(struct inode * inode)3011 static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
3012 {
3013 	smp_mb();
3014 	ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
3015 }
3016 
3017 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3018 
3019 /* For ioend & aio unwritten conversion wait queues */
3020 #define EXT4_WQ_HASH_SZ		37
3021 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3022 					    EXT4_WQ_HASH_SZ])
3023 #define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
3024 					     EXT4_WQ_HASH_SZ])
3025 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3026 extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
3027 
3028 #define EXT4_RESIZING	0
3029 extern int ext4_resize_begin(struct super_block *sb);
3030 extern void ext4_resize_end(struct super_block *sb);
3031 
3032 #endif	/* __KERNEL__ */
3033 
3034 #endif	/* _EXT4_H */
3035