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1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  ext4.h
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/include/linux/minix_fs.h
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  */
16 
17 #ifndef _EXT4_H
18 #define _EXT4_H
19 
20 #include <linux/types.h>
21 #include <linux/blkdev.h>
22 #include <linux/magic.h>
23 #include <linux/jbd2.h>
24 #include <linux/quota.h>
25 #include <linux/rwsem.h>
26 #include <linux/rbtree.h>
27 #include <linux/seqlock.h>
28 #include <linux/mutex.h>
29 #include <linux/timer.h>
30 #include <linux/version.h>
31 #include <linux/wait.h>
32 #include <linux/sched/signal.h>
33 #include <linux/blockgroup_lock.h>
34 #include <linux/percpu_counter.h>
35 #include <linux/ratelimit.h>
36 #include <crypto/hash.h>
37 #include <linux/falloc.h>
38 #include <linux/percpu-rwsem.h>
39 #ifdef __KERNEL__
40 #include <linux/compat.h>
41 #endif
42 
43 #define __FS_HAS_ENCRYPTION IS_ENABLED(CONFIG_EXT4_FS_ENCRYPTION)
44 #include <linux/fscrypt.h>
45 
46 #include <linux/compiler.h>
47 
48 /* Until this gets included into linux/compiler-gcc.h */
49 #ifndef __nonstring
50 #if defined(GCC_VERSION) && (GCC_VERSION >= 80000)
51 #define __nonstring __attribute__((nonstring))
52 #else
53 #define __nonstring
54 #endif
55 #endif
56 
57 /*
58  * The fourth extended filesystem constants/structures
59  */
60 
61 /*
62  * with AGGRESSIVE_CHECK allocator runs consistency checks over
63  * structures. these checks slow things down a lot
64  */
65 #define AGGRESSIVE_CHECK__
66 
67 /*
68  * with DOUBLE_CHECK defined mballoc creates persistent in-core
69  * bitmaps, maintains and uses them to check for double allocations
70  */
71 #define DOUBLE_CHECK__
72 
73 /*
74  * Define EXT4FS_DEBUG to produce debug messages
75  */
76 #undef EXT4FS_DEBUG
77 
78 /*
79  * Debug code
80  */
81 #ifdef EXT4FS_DEBUG
82 #define ext4_debug(f, a...)						\
83 	do {								\
84 		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
85 			__FILE__, __LINE__, __func__);			\
86 		printk(KERN_DEBUG f, ## a);				\
87 	} while (0)
88 #else
89 #define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
90 #endif
91 
92 /*
93  * Turn on EXT_DEBUG to get lots of info about extents operations.
94  */
95 #define EXT_DEBUG__
96 #ifdef EXT_DEBUG
97 #define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
98 #else
99 #define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
100 #endif
101 
102 /* data type for block offset of block group */
103 typedef int ext4_grpblk_t;
104 
105 /* data type for filesystem-wide blocks number */
106 typedef unsigned long long ext4_fsblk_t;
107 
108 /* data type for file logical block number */
109 typedef __u32 ext4_lblk_t;
110 
111 /* data type for block group number */
112 typedef unsigned int ext4_group_t;
113 
114 enum SHIFT_DIRECTION {
115 	SHIFT_LEFT = 0,
116 	SHIFT_RIGHT,
117 };
118 
119 /*
120  * Flags used in mballoc's allocation_context flags field.
121  *
122  * Also used to show what's going on for debugging purposes when the
123  * flag field is exported via the traceport interface
124  */
125 
126 /* prefer goal again. length */
127 #define EXT4_MB_HINT_MERGE		0x0001
128 /* blocks already reserved */
129 #define EXT4_MB_HINT_RESERVED		0x0002
130 /* metadata is being allocated */
131 #define EXT4_MB_HINT_METADATA		0x0004
132 /* first blocks in the file */
133 #define EXT4_MB_HINT_FIRST		0x0008
134 /* search for the best chunk */
135 #define EXT4_MB_HINT_BEST		0x0010
136 /* data is being allocated */
137 #define EXT4_MB_HINT_DATA		0x0020
138 /* don't preallocate (for tails) */
139 #define EXT4_MB_HINT_NOPREALLOC		0x0040
140 /* allocate for locality group */
141 #define EXT4_MB_HINT_GROUP_ALLOC	0x0080
142 /* allocate goal blocks or none */
143 #define EXT4_MB_HINT_GOAL_ONLY		0x0100
144 /* goal is meaningful */
145 #define EXT4_MB_HINT_TRY_GOAL		0x0200
146 /* blocks already pre-reserved by delayed allocation */
147 #define EXT4_MB_DELALLOC_RESERVED	0x0400
148 /* We are doing stream allocation */
149 #define EXT4_MB_STREAM_ALLOC		0x0800
150 /* Use reserved root blocks if needed */
151 #define EXT4_MB_USE_ROOT_BLOCKS		0x1000
152 /* Use blocks from reserved pool */
153 #define EXT4_MB_USE_RESERVED		0x2000
154 
155 struct ext4_allocation_request {
156 	/* target inode for block we're allocating */
157 	struct inode *inode;
158 	/* how many blocks we want to allocate */
159 	unsigned int len;
160 	/* logical block in target inode */
161 	ext4_lblk_t logical;
162 	/* the closest logical allocated block to the left */
163 	ext4_lblk_t lleft;
164 	/* the closest logical allocated block to the right */
165 	ext4_lblk_t lright;
166 	/* phys. target (a hint) */
167 	ext4_fsblk_t goal;
168 	/* phys. block for the closest logical allocated block to the left */
169 	ext4_fsblk_t pleft;
170 	/* phys. block for the closest logical allocated block to the right */
171 	ext4_fsblk_t pright;
172 	/* flags. see above EXT4_MB_HINT_* */
173 	unsigned int flags;
174 };
175 
176 /*
177  * Logical to physical block mapping, used by ext4_map_blocks()
178  *
179  * This structure is used to pass requests into ext4_map_blocks() as
180  * well as to store the information returned by ext4_map_blocks().  It
181  * takes less room on the stack than a struct buffer_head.
182  */
183 #define EXT4_MAP_NEW		(1 << BH_New)
184 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
185 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
186 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
187 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
188 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY)
189 
190 struct ext4_map_blocks {
191 	ext4_fsblk_t m_pblk;
192 	ext4_lblk_t m_lblk;
193 	unsigned int m_len;
194 	unsigned int m_flags;
195 };
196 
197 /*
198  * Block validity checking, system zone rbtree.
199  */
200 struct ext4_system_blocks {
201 	struct rb_root root;
202 	struct rcu_head rcu;
203 };
204 
205 /*
206  * Flags for ext4_io_end->flags
207  */
208 #define	EXT4_IO_END_UNWRITTEN	0x0001
209 
210 /*
211  * For converting unwritten extents on a work queue. 'handle' is used for
212  * buffered writeback.
213  */
214 typedef struct ext4_io_end {
215 	struct list_head	list;		/* per-file finished IO list */
216 	handle_t		*handle;	/* handle reserved for extent
217 						 * conversion */
218 	struct inode		*inode;		/* file being written to */
219 	struct bio		*bio;		/* Linked list of completed
220 						 * bios covering the extent */
221 	unsigned int		flag;		/* unwritten or not */
222 	atomic_t		count;		/* reference counter */
223 	loff_t			offset;		/* offset in the file */
224 	ssize_t			size;		/* size of the extent */
225 } ext4_io_end_t;
226 
227 struct ext4_io_submit {
228 	struct writeback_control *io_wbc;
229 	struct bio		*io_bio;
230 	ext4_io_end_t		*io_end;
231 	sector_t		io_next_block;
232 };
233 
234 /*
235  * Special inodes numbers
236  */
237 #define	EXT4_BAD_INO		 1	/* Bad blocks inode */
238 #define EXT4_ROOT_INO		 2	/* Root inode */
239 #define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
240 #define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
241 #define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
242 #define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
243 #define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
244 #define EXT4_JOURNAL_INO	 8	/* Journal inode */
245 
246 /* First non-reserved inode for old ext4 filesystems */
247 #define EXT4_GOOD_OLD_FIRST_INO	11
248 
249 /*
250  * Maximal count of links to a file
251  */
252 #define EXT4_LINK_MAX		65000
253 
254 /*
255  * Macro-instructions used to manage several block sizes
256  */
257 #define EXT4_MIN_BLOCK_SIZE		1024
258 #define	EXT4_MAX_BLOCK_SIZE		65536
259 #define EXT4_MIN_BLOCK_LOG_SIZE		10
260 #define EXT4_MAX_BLOCK_LOG_SIZE		16
261 #define EXT4_MAX_CLUSTER_LOG_SIZE	30
262 #ifdef __KERNEL__
263 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
264 #else
265 # define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
266 #endif
267 #define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
268 #define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
269 					 EXT4_SB(s)->s_cluster_bits)
270 #ifdef __KERNEL__
271 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
272 # define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
273 #else
274 # define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
275 #endif
276 #ifdef __KERNEL__
277 #define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
278 #define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
279 #define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
280 #else
281 #define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
282 				 EXT4_GOOD_OLD_INODE_SIZE : \
283 				 (s)->s_inode_size)
284 #define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
285 				 EXT4_GOOD_OLD_FIRST_INO : \
286 				 (s)->s_first_ino)
287 #endif
288 #define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
289 #define EXT4_MAX_BLOCKS(size, offset, blkbits) \
290 	((EXT4_BLOCK_ALIGN(size + offset, blkbits) >> blkbits) - (offset >> \
291 								  blkbits))
292 
293 /* Translate a block number to a cluster number */
294 #define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
295 /* Translate a cluster number to a block number */
296 #define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
297 /* Translate # of blks to # of clusters */
298 #define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
299 				 (sbi)->s_cluster_bits)
300 /* Mask out the low bits to get the starting block of the cluster */
301 #define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
302 				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
303 #define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
304 				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
305 /* Get the cluster offset */
306 #define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
307 				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
308 #define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
309 				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
310 
311 /*
312  * Structure of a blocks group descriptor
313  */
314 struct ext4_group_desc
315 {
316 	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
317 	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
318 	__le32	bg_inode_table_lo;	/* Inodes table block */
319 	__le16	bg_free_blocks_count_lo;/* Free blocks count */
320 	__le16	bg_free_inodes_count_lo;/* Free inodes count */
321 	__le16	bg_used_dirs_count_lo;	/* Directories count */
322 	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
323 	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
324 	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
325 	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
326 	__le16  bg_itable_unused_lo;	/* Unused inodes count */
327 	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
328 	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
329 	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
330 	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
331 	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
332 	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
333 	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
334 	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
335 	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
336 	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
337 	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
338 	__u32   bg_reserved;
339 };
340 
341 #define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
342 	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
343 	 sizeof(__le16))
344 #define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
345 	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
346 	 sizeof(__le16))
347 
348 /*
349  * Structure of a flex block group info
350  */
351 
352 struct flex_groups {
353 	atomic64_t	free_clusters;
354 	atomic_t	free_inodes;
355 	atomic_t	used_dirs;
356 };
357 
358 #define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
359 #define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
360 #define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
361 
362 /*
363  * Macro-instructions used to manage group descriptors
364  */
365 #define EXT4_MIN_DESC_SIZE		32
366 #define EXT4_MIN_DESC_SIZE_64BIT	64
367 #define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
368 #define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
369 #ifdef __KERNEL__
370 # define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
371 # define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
372 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
373 # define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
374 # define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
375 #else
376 # define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
377 # define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
378 # define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
379 #endif
380 
381 /*
382  * Constants relative to the data blocks
383  */
384 #define	EXT4_NDIR_BLOCKS		12
385 #define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
386 #define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
387 #define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
388 #define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
389 
390 /*
391  * Inode flags
392  */
393 #define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
394 #define	EXT4_UNRM_FL			0x00000002 /* Undelete */
395 #define	EXT4_COMPR_FL			0x00000004 /* Compress file */
396 #define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
397 #define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
398 #define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
399 #define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
400 #define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
401 /* Reserved for compression usage... */
402 #define EXT4_DIRTY_FL			0x00000100
403 #define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
404 #define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
405 	/* nb: was previously EXT2_ECOMPR_FL */
406 #define EXT4_ENCRYPT_FL			0x00000800 /* encrypted file */
407 /* End compression flags --- maybe not all used */
408 #define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
409 #define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
410 #define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
411 #define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
412 #define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
413 #define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
414 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
415 #define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
416 #define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
417 #define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
418 #define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
419 #define EXT4_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
420 #define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
421 
422 #define EXT4_FL_USER_VISIBLE		0x304BDFFF /* User visible flags */
423 #define EXT4_FL_USER_MODIFIABLE		0x204BC0FF /* User modifiable flags */
424 
425 /* Flags we can manipulate with through EXT4_IOC_FSSETXATTR */
426 #define EXT4_FL_XFLAG_VISIBLE		(EXT4_SYNC_FL | \
427 					 EXT4_IMMUTABLE_FL | \
428 					 EXT4_APPEND_FL | \
429 					 EXT4_NODUMP_FL | \
430 					 EXT4_NOATIME_FL | \
431 					 EXT4_PROJINHERIT_FL)
432 
433 /* Flags that should be inherited by new inodes from their parent. */
434 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
435 			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
436 			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
437 			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\
438 			   EXT4_PROJINHERIT_FL)
439 
440 /* Flags that are appropriate for regular files (all but dir-specific ones). */
441 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
442 
443 /* Flags that are appropriate for non-directories/regular files. */
444 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
445 
446 /* The only flags that should be swapped */
447 #define EXT4_FL_SHOULD_SWAP (EXT4_HUGE_FILE_FL | EXT4_EXTENTS_FL)
448 
449 /* Mask out flags that are inappropriate for the given type of inode. */
ext4_mask_flags(umode_t mode,__u32 flags)450 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
451 {
452 	if (S_ISDIR(mode))
453 		return flags;
454 	else if (S_ISREG(mode))
455 		return flags & EXT4_REG_FLMASK;
456 	else
457 		return flags & EXT4_OTHER_FLMASK;
458 }
459 
460 /*
461  * Inode flags used for atomic set/get
462  */
463 enum {
464 	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
465 	EXT4_INODE_UNRM		= 1,	/* Undelete */
466 	EXT4_INODE_COMPR	= 2,	/* Compress file */
467 	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
468 	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
469 	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
470 	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
471 	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
472 /* Reserved for compression usage... */
473 	EXT4_INODE_DIRTY	= 8,
474 	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
475 	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
476 	EXT4_INODE_ENCRYPT	= 11,	/* Encrypted file */
477 /* End compression flags --- maybe not all used */
478 	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
479 	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
480 	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
481 	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
482 	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
483 	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
484 	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
485 	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
486 	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
487 	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
488 	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
489 	EXT4_INODE_PROJINHERIT	= 29,	/* Create with parents projid */
490 	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
491 };
492 
493 /*
494  * Since it's pretty easy to mix up bit numbers and hex values, we use a
495  * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
496  * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
497  * any extra space in the compiled kernel image, otherwise, the build will fail.
498  * It's important that these values are the same, since we are using
499  * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
500  * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
501  * values found in ext2, ext3 and ext4 filesystems, and of course the values
502  * defined in e2fsprogs.
503  *
504  * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
505  */
506 #define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
507 #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
508 
ext4_check_flag_values(void)509 static inline void ext4_check_flag_values(void)
510 {
511 	CHECK_FLAG_VALUE(SECRM);
512 	CHECK_FLAG_VALUE(UNRM);
513 	CHECK_FLAG_VALUE(COMPR);
514 	CHECK_FLAG_VALUE(SYNC);
515 	CHECK_FLAG_VALUE(IMMUTABLE);
516 	CHECK_FLAG_VALUE(APPEND);
517 	CHECK_FLAG_VALUE(NODUMP);
518 	CHECK_FLAG_VALUE(NOATIME);
519 	CHECK_FLAG_VALUE(DIRTY);
520 	CHECK_FLAG_VALUE(COMPRBLK);
521 	CHECK_FLAG_VALUE(NOCOMPR);
522 	CHECK_FLAG_VALUE(ENCRYPT);
523 	CHECK_FLAG_VALUE(INDEX);
524 	CHECK_FLAG_VALUE(IMAGIC);
525 	CHECK_FLAG_VALUE(JOURNAL_DATA);
526 	CHECK_FLAG_VALUE(NOTAIL);
527 	CHECK_FLAG_VALUE(DIRSYNC);
528 	CHECK_FLAG_VALUE(TOPDIR);
529 	CHECK_FLAG_VALUE(HUGE_FILE);
530 	CHECK_FLAG_VALUE(EXTENTS);
531 	CHECK_FLAG_VALUE(EA_INODE);
532 	CHECK_FLAG_VALUE(EOFBLOCKS);
533 	CHECK_FLAG_VALUE(INLINE_DATA);
534 	CHECK_FLAG_VALUE(PROJINHERIT);
535 	CHECK_FLAG_VALUE(RESERVED);
536 }
537 
538 /* Used to pass group descriptor data when online resize is done */
539 struct ext4_new_group_input {
540 	__u32 group;		/* Group number for this data */
541 	__u64 block_bitmap;	/* Absolute block number of block bitmap */
542 	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
543 	__u64 inode_table;	/* Absolute block number of inode table start */
544 	__u32 blocks_count;	/* Total number of blocks in this group */
545 	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
546 	__u16 unused;
547 };
548 
549 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
550 struct compat_ext4_new_group_input {
551 	u32 group;
552 	compat_u64 block_bitmap;
553 	compat_u64 inode_bitmap;
554 	compat_u64 inode_table;
555 	u32 blocks_count;
556 	u16 reserved_blocks;
557 	u16 unused;
558 };
559 #endif
560 
561 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
562 struct ext4_new_group_data {
563 	__u32 group;
564 	__u64 block_bitmap;
565 	__u64 inode_bitmap;
566 	__u64 inode_table;
567 	__u32 blocks_count;
568 	__u16 reserved_blocks;
569 	__u16 mdata_blocks;
570 	__u32 free_clusters_count;
571 };
572 
573 /* Indexes used to index group tables in ext4_new_group_data */
574 enum {
575 	BLOCK_BITMAP = 0,	/* block bitmap */
576 	INODE_BITMAP,		/* inode bitmap */
577 	INODE_TABLE,		/* inode tables */
578 	GROUP_TABLE_COUNT,
579 };
580 
581 /*
582  * Flags used by ext4_map_blocks()
583  */
584 	/* Allocate any needed blocks and/or convert an unwritten
585 	   extent to be an initialized ext4 */
586 #define EXT4_GET_BLOCKS_CREATE			0x0001
587 	/* Request the creation of an unwritten extent */
588 #define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
589 #define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
590 						 EXT4_GET_BLOCKS_CREATE)
591 	/* Caller is from the delayed allocation writeout path
592 	 * finally doing the actual allocation of delayed blocks */
593 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
594 	/* caller is from the direct IO path, request to creation of an
595 	unwritten extents if not allocated, split the unwritten
596 	extent if blocks has been preallocated already*/
597 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
598 #define EXT4_GET_BLOCKS_CONVERT			0x0010
599 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
600 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
601 	/* Convert extent to initialized after IO complete */
602 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
603 					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
604 	/* Eventual metadata allocation (due to growing extent tree)
605 	 * should not fail, so try to use reserved blocks for that.*/
606 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
607 	/* Don't normalize allocation size (used for fallocate) */
608 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
609 	/* Request will not result in inode size update (user for fallocate) */
610 #define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
611 	/* Convert written extents to unwritten */
612 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
613 	/* Write zeros to newly created written extents */
614 #define EXT4_GET_BLOCKS_ZERO			0x0200
615 #define EXT4_GET_BLOCKS_CREATE_ZERO		(EXT4_GET_BLOCKS_CREATE |\
616 					EXT4_GET_BLOCKS_ZERO)
617 	/* Caller will submit data before dropping transaction handle. This
618 	 * allows jbd2 to avoid submitting data before commit. */
619 #define EXT4_GET_BLOCKS_IO_SUBMIT		0x0400
620 
621 /*
622  * The bit position of these flags must not overlap with any of the
623  * EXT4_GET_BLOCKS_*.  They are used by ext4_find_extent(),
624  * read_extent_tree_block(), ext4_split_extent_at(),
625  * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
626  * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
627  * caching the extents when reading from the extent tree while a
628  * truncate or punch hole operation is in progress.
629  */
630 #define EXT4_EX_NOCACHE				0x40000000
631 #define EXT4_EX_FORCE_CACHE			0x20000000
632 
633 /*
634  * Flags used by ext4_free_blocks
635  */
636 #define EXT4_FREE_BLOCKS_METADATA		0x0001
637 #define EXT4_FREE_BLOCKS_FORGET			0x0002
638 #define EXT4_FREE_BLOCKS_VALIDATED		0x0004
639 #define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE		0x0008
640 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
641 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
642 
643 /*
644  * ioctl commands
645  */
646 #define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
647 #define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
648 #define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
649 #define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
650 #define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
651 #define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
652 #define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
653 #define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
654 #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
655 #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
656 #define EXT4_IOC_MIGRATE		_IO('f', 9)
657  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
658  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
659 #define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
660 #define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
661 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
662 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
663 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
664 #define EXT4_IOC_SET_ENCRYPTION_POLICY	FS_IOC_SET_ENCRYPTION_POLICY
665 #define EXT4_IOC_GET_ENCRYPTION_PWSALT	FS_IOC_GET_ENCRYPTION_PWSALT
666 #define EXT4_IOC_GET_ENCRYPTION_POLICY	FS_IOC_GET_ENCRYPTION_POLICY
667 
668 #define EXT4_IOC_FSGETXATTR		FS_IOC_FSGETXATTR
669 #define EXT4_IOC_FSSETXATTR		FS_IOC_FSSETXATTR
670 
671 #define EXT4_IOC_SHUTDOWN _IOR ('X', 125, __u32)
672 
673 /*
674  * Flags for going down operation
675  */
676 #define EXT4_GOING_FLAGS_DEFAULT		0x0	/* going down */
677 #define EXT4_GOING_FLAGS_LOGFLUSH		0x1	/* flush log but not data */
678 #define EXT4_GOING_FLAGS_NOLOGFLUSH		0x2	/* don't flush log nor data */
679 
680 
681 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
682 /*
683  * ioctl commands in 32 bit emulation
684  */
685 #define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
686 #define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
687 #define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
688 #define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
689 #define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
690 #define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
691 #define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
692 #define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
693 #define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
694 #define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
695 #endif
696 
697 /* Max physical block we can address w/o extents */
698 #define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
699 
700 /* Max logical block we can support */
701 #define EXT4_MAX_LOGICAL_BLOCK		0xFFFFFFFF
702 
703 /*
704  * Structure of an inode on the disk
705  */
706 struct ext4_inode {
707 	__le16	i_mode;		/* File mode */
708 	__le16	i_uid;		/* Low 16 bits of Owner Uid */
709 	__le32	i_size_lo;	/* Size in bytes */
710 	__le32	i_atime;	/* Access time */
711 	__le32	i_ctime;	/* Inode Change time */
712 	__le32	i_mtime;	/* Modification time */
713 	__le32	i_dtime;	/* Deletion Time */
714 	__le16	i_gid;		/* Low 16 bits of Group Id */
715 	__le16	i_links_count;	/* Links count */
716 	__le32	i_blocks_lo;	/* Blocks count */
717 	__le32	i_flags;	/* File flags */
718 	union {
719 		struct {
720 			__le32  l_i_version;
721 		} linux1;
722 		struct {
723 			__u32  h_i_translator;
724 		} hurd1;
725 		struct {
726 			__u32  m_i_reserved1;
727 		} masix1;
728 	} osd1;				/* OS dependent 1 */
729 	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
730 	__le32	i_generation;	/* File version (for NFS) */
731 	__le32	i_file_acl_lo;	/* File ACL */
732 	__le32	i_size_high;
733 	__le32	i_obso_faddr;	/* Obsoleted fragment address */
734 	union {
735 		struct {
736 			__le16	l_i_blocks_high; /* were l_i_reserved1 */
737 			__le16	l_i_file_acl_high;
738 			__le16	l_i_uid_high;	/* these 2 fields */
739 			__le16	l_i_gid_high;	/* were reserved2[0] */
740 			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
741 			__le16	l_i_reserved;
742 		} linux2;
743 		struct {
744 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
745 			__u16	h_i_mode_high;
746 			__u16	h_i_uid_high;
747 			__u16	h_i_gid_high;
748 			__u32	h_i_author;
749 		} hurd2;
750 		struct {
751 			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
752 			__le16	m_i_file_acl_high;
753 			__u32	m_i_reserved2[2];
754 		} masix2;
755 	} osd2;				/* OS dependent 2 */
756 	__le16	i_extra_isize;
757 	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
758 	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
759 	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
760 	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
761 	__le32  i_crtime;       /* File Creation time */
762 	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
763 	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
764 	__le32	i_projid;	/* Project ID */
765 };
766 
767 struct move_extent {
768 	__u32 reserved;		/* should be zero */
769 	__u32 donor_fd;		/* donor file descriptor */
770 	__u64 orig_start;	/* logical start offset in block for orig */
771 	__u64 donor_start;	/* logical start offset in block for donor */
772 	__u64 len;		/* block length to be moved */
773 	__u64 moved_len;	/* moved block length */
774 };
775 
776 #define EXT4_EPOCH_BITS 2
777 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
778 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
779 
780 /*
781  * Extended fields will fit into an inode if the filesystem was formatted
782  * with large inodes (-I 256 or larger) and there are not currently any EAs
783  * consuming all of the available space. For new inodes we always reserve
784  * enough space for the kernel's known extended fields, but for inodes
785  * created with an old kernel this might not have been the case. None of
786  * the extended inode fields is critical for correct filesystem operation.
787  * This macro checks if a certain field fits in the inode. Note that
788  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
789  */
790 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
791 	((offsetof(typeof(*ext4_inode), field) +	\
792 	  sizeof((ext4_inode)->field))			\
793 	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
794 	    (einode)->i_extra_isize))			\
795 
796 /*
797  * We use an encoding that preserves the times for extra epoch "00":
798  *
799  * extra  msb of                         adjust for signed
800  * epoch  32-bit                         32-bit tv_sec to
801  * bits   time    decoded 64-bit tv_sec  64-bit tv_sec      valid time range
802  * 0 0    1    -0x80000000..-0x00000001  0x000000000 1901-12-13..1969-12-31
803  * 0 0    0    0x000000000..0x07fffffff  0x000000000 1970-01-01..2038-01-19
804  * 0 1    1    0x080000000..0x0ffffffff  0x100000000 2038-01-19..2106-02-07
805  * 0 1    0    0x100000000..0x17fffffff  0x100000000 2106-02-07..2174-02-25
806  * 1 0    1    0x180000000..0x1ffffffff  0x200000000 2174-02-25..2242-03-16
807  * 1 0    0    0x200000000..0x27fffffff  0x200000000 2242-03-16..2310-04-04
808  * 1 1    1    0x280000000..0x2ffffffff  0x300000000 2310-04-04..2378-04-22
809  * 1 1    0    0x300000000..0x37fffffff  0x300000000 2378-04-22..2446-05-10
810  *
811  * Note that previous versions of the kernel on 64-bit systems would
812  * incorrectly use extra epoch bits 1,1 for dates between 1901 and
813  * 1970.  e2fsck will correct this, assuming that it is run on the
814  * affected filesystem before 2242.
815  */
816 
ext4_encode_extra_time(struct timespec64 * time)817 static inline __le32 ext4_encode_extra_time(struct timespec64 *time)
818 {
819 	u32 extra =((time->tv_sec - (s32)time->tv_sec) >> 32) & EXT4_EPOCH_MASK;
820 	return cpu_to_le32(extra | (time->tv_nsec << EXT4_EPOCH_BITS));
821 }
822 
ext4_decode_extra_time(struct timespec64 * time,__le32 extra)823 static inline void ext4_decode_extra_time(struct timespec64 *time,
824 					  __le32 extra)
825 {
826 	if (unlikely(extra & cpu_to_le32(EXT4_EPOCH_MASK))) {
827 
828 #if 1
829 		/* Handle legacy encoding of pre-1970 dates with epoch
830 		 * bits 1,1. (This backwards compatibility may be removed
831 		 * at the discretion of the ext4 developers.)
832 		 */
833 		u64 extra_bits = le32_to_cpu(extra) & EXT4_EPOCH_MASK;
834 		if (extra_bits == 3 && ((time->tv_sec) & 0x80000000) != 0)
835 			extra_bits = 0;
836 		time->tv_sec += extra_bits << 32;
837 #else
838 		time->tv_sec += (u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK) << 32;
839 #endif
840 	}
841 	time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
842 }
843 
844 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)				\
845 do {										\
846 	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);		\
847 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     {\
848 		(raw_inode)->xtime ## _extra =					\
849 				ext4_encode_extra_time(&(inode)->xtime);	\
850 		}								\
851 } while (0)
852 
853 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
854 do {									       \
855 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
856 		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
857 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
858 		(raw_inode)->xtime ## _extra =				       \
859 				ext4_encode_extra_time(&(einode)->xtime);      \
860 } while (0)
861 
862 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)				\
863 do {										\
864 	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);	\
865 	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {	\
866 		ext4_decode_extra_time(&(inode)->xtime,				\
867 				       raw_inode->xtime ## _extra);		\
868 		}								\
869 	else									\
870 		(inode)->xtime.tv_nsec = 0;					\
871 } while (0)
872 
873 
874 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
875 do {									       \
876 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
877 		(einode)->xtime.tv_sec = 				       \
878 			(signed)le32_to_cpu((raw_inode)->xtime);	       \
879 	else								       \
880 		(einode)->xtime.tv_sec = 0;				       \
881 	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
882 		ext4_decode_extra_time(&(einode)->xtime,		       \
883 				       raw_inode->xtime ## _extra);	       \
884 	else								       \
885 		(einode)->xtime.tv_nsec = 0;				       \
886 } while (0)
887 
888 #define i_disk_version osd1.linux1.l_i_version
889 
890 #if defined(__KERNEL__) || defined(__linux__)
891 #define i_reserved1	osd1.linux1.l_i_reserved1
892 #define i_file_acl_high	osd2.linux2.l_i_file_acl_high
893 #define i_blocks_high	osd2.linux2.l_i_blocks_high
894 #define i_uid_low	i_uid
895 #define i_gid_low	i_gid
896 #define i_uid_high	osd2.linux2.l_i_uid_high
897 #define i_gid_high	osd2.linux2.l_i_gid_high
898 #define i_checksum_lo	osd2.linux2.l_i_checksum_lo
899 
900 #elif defined(__GNU__)
901 
902 #define i_translator	osd1.hurd1.h_i_translator
903 #define i_uid_high	osd2.hurd2.h_i_uid_high
904 #define i_gid_high	osd2.hurd2.h_i_gid_high
905 #define i_author	osd2.hurd2.h_i_author
906 
907 #elif defined(__masix__)
908 
909 #define i_reserved1	osd1.masix1.m_i_reserved1
910 #define i_file_acl_high	osd2.masix2.m_i_file_acl_high
911 #define i_reserved2	osd2.masix2.m_i_reserved2
912 
913 #endif /* defined(__KERNEL__) || defined(__linux__) */
914 
915 #include "extents_status.h"
916 
917 /*
918  * Lock subclasses for i_data_sem in the ext4_inode_info structure.
919  *
920  * These are needed to avoid lockdep false positives when we need to
921  * allocate blocks to the quota inode during ext4_map_blocks(), while
922  * holding i_data_sem for a normal (non-quota) inode.  Since we don't
923  * do quota tracking for the quota inode, this avoids deadlock (as
924  * well as infinite recursion, since it isn't turtles all the way
925  * down...)
926  *
927  *  I_DATA_SEM_NORMAL - Used for most inodes
928  *  I_DATA_SEM_OTHER  - Used by move_inode.c for the second normal inode
929  *			  where the second inode has larger inode number
930  *			  than the first
931  *  I_DATA_SEM_QUOTA  - Used for quota inodes only
932  */
933 enum {
934 	I_DATA_SEM_NORMAL = 0,
935 	I_DATA_SEM_OTHER,
936 	I_DATA_SEM_QUOTA,
937 };
938 
939 
940 /*
941  * fourth extended file system inode data in memory
942  */
943 struct ext4_inode_info {
944 	__le32	i_data[15];	/* unconverted */
945 	__u32	i_dtime;
946 	ext4_fsblk_t	i_file_acl;
947 
948 	/*
949 	 * i_block_group is the number of the block group which contains
950 	 * this file's inode.  Constant across the lifetime of the inode,
951 	 * it is used for making block allocation decisions - we try to
952 	 * place a file's data blocks near its inode block, and new inodes
953 	 * near to their parent directory's inode.
954 	 */
955 	ext4_group_t	i_block_group;
956 	ext4_lblk_t	i_dir_start_lookup;
957 #if (BITS_PER_LONG < 64)
958 	unsigned long	i_state_flags;		/* Dynamic state flags */
959 #endif
960 	unsigned long	i_flags;
961 
962 	/*
963 	 * Extended attributes can be read independently of the main file
964 	 * data. Taking i_mutex even when reading would cause contention
965 	 * between readers of EAs and writers of regular file data, so
966 	 * instead we synchronize on xattr_sem when reading or changing
967 	 * EAs.
968 	 */
969 	struct rw_semaphore xattr_sem;
970 
971 	struct list_head i_orphan;	/* unlinked but open inodes */
972 
973 	/*
974 	 * i_disksize keeps track of what the inode size is ON DISK, not
975 	 * in memory.  During truncate, i_size is set to the new size by
976 	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
977 	 * set i_disksize to 0 until the truncate is actually under way.
978 	 *
979 	 * The intent is that i_disksize always represents the blocks which
980 	 * are used by this file.  This allows recovery to restart truncate
981 	 * on orphans if we crash during truncate.  We actually write i_disksize
982 	 * into the on-disk inode when writing inodes out, instead of i_size.
983 	 *
984 	 * The only time when i_disksize and i_size may be different is when
985 	 * a truncate is in progress.  The only things which change i_disksize
986 	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
987 	 */
988 	loff_t	i_disksize;
989 
990 	/*
991 	 * i_data_sem is for serialising ext4_truncate() against
992 	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
993 	 * data tree are chopped off during truncate. We can't do that in
994 	 * ext4 because whenever we perform intermediate commits during
995 	 * truncate, the inode and all the metadata blocks *must* be in a
996 	 * consistent state which allows truncation of the orphans to restart
997 	 * during recovery.  Hence we must fix the get_block-vs-truncate race
998 	 * by other means, so we have i_data_sem.
999 	 */
1000 	struct rw_semaphore i_data_sem;
1001 	/*
1002 	 * i_mmap_sem is for serializing page faults with truncate / punch hole
1003 	 * operations. We have to make sure that new page cannot be faulted in
1004 	 * a section of the inode that is being punched. We cannot easily use
1005 	 * i_data_sem for this since we need protection for the whole punch
1006 	 * operation and i_data_sem ranks below transaction start so we have
1007 	 * to occasionally drop it.
1008 	 */
1009 	struct rw_semaphore i_mmap_sem;
1010 	struct inode vfs_inode;
1011 	struct jbd2_inode *jinode;
1012 
1013 	spinlock_t i_raw_lock;	/* protects updates to the raw inode */
1014 
1015 	/*
1016 	 * File creation time. Its function is same as that of
1017 	 * struct timespec64 i_{a,c,m}time in the generic inode.
1018 	 */
1019 	struct timespec64 i_crtime;
1020 
1021 	/* mballoc */
1022 	struct list_head i_prealloc_list;
1023 	spinlock_t i_prealloc_lock;
1024 
1025 	/* extents status tree */
1026 	struct ext4_es_tree i_es_tree;
1027 	rwlock_t i_es_lock;
1028 	struct list_head i_es_list;
1029 	unsigned int i_es_all_nr;	/* protected by i_es_lock */
1030 	unsigned int i_es_shk_nr;	/* protected by i_es_lock */
1031 	ext4_lblk_t i_es_shrink_lblk;	/* Offset where we start searching for
1032 					   extents to shrink. Protected by
1033 					   i_es_lock  */
1034 
1035 	/* ialloc */
1036 	ext4_group_t	i_last_alloc_group;
1037 
1038 	/* allocation reservation info for delalloc */
1039 	/* In case of bigalloc, this refer to clusters rather than blocks */
1040 	unsigned int i_reserved_data_blocks;
1041 	ext4_lblk_t i_da_metadata_calc_last_lblock;
1042 	int i_da_metadata_calc_len;
1043 
1044 	/* on-disk additional length */
1045 	__u16 i_extra_isize;
1046 
1047 	/* Indicate the inline data space. */
1048 	u16 i_inline_off;
1049 	u16 i_inline_size;
1050 
1051 #ifdef CONFIG_QUOTA
1052 	/* quota space reservation, managed internally by quota code */
1053 	qsize_t i_reserved_quota;
1054 #endif
1055 
1056 	/* Lock protecting lists below */
1057 	spinlock_t i_completed_io_lock;
1058 	/*
1059 	 * Completed IOs that need unwritten extents handling and have
1060 	 * transaction reserved
1061 	 */
1062 	struct list_head i_rsv_conversion_list;
1063 	struct work_struct i_rsv_conversion_work;
1064 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
1065 
1066 	spinlock_t i_block_reservation_lock;
1067 
1068 	/*
1069 	 * Transactions that contain inode's metadata needed to complete
1070 	 * fsync and fdatasync, respectively.
1071 	 */
1072 	tid_t i_sync_tid;
1073 	tid_t i_datasync_tid;
1074 
1075 #ifdef CONFIG_QUOTA
1076 	struct dquot *i_dquot[MAXQUOTAS];
1077 #endif
1078 
1079 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
1080 	__u32 i_csum_seed;
1081 
1082 	kprojid_t i_projid;
1083 };
1084 
1085 /*
1086  * File system states
1087  */
1088 #define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
1089 #define	EXT4_ERROR_FS			0x0002	/* Errors detected */
1090 #define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
1091 
1092 /*
1093  * Misc. filesystem flags
1094  */
1095 #define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
1096 #define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
1097 #define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
1098 
1099 /*
1100  * Mount flags set via mount options or defaults
1101  */
1102 #define EXT4_MOUNT_NO_MBCACHE		0x00001 /* Do not use mbcache */
1103 #define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
1104 #define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
1105 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
1106 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
1107 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
1108 #define EXT4_MOUNT_ERRORS_MASK		0x00070
1109 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
1110 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
1111 #ifdef CONFIG_FS_DAX
1112 #define EXT4_MOUNT_DAX			0x00200	/* Direct Access */
1113 #else
1114 #define EXT4_MOUNT_DAX			0
1115 #endif
1116 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
1117 #define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
1118 #define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
1119 #define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
1120 #define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
1121 #define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
1122 #define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
1123 #define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
1124 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
1125 #define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
1126 #define EXT4_MOUNT_QUOTA		0x40000 /* Some quota option set */
1127 #define EXT4_MOUNT_USRQUOTA		0x80000 /* "old" user quota,
1128 						 * enable enforcement for hidden
1129 						 * quota files */
1130 #define EXT4_MOUNT_GRPQUOTA		0x100000 /* "old" group quota, enable
1131 						  * enforcement for hidden quota
1132 						  * files */
1133 #define EXT4_MOUNT_PRJQUOTA		0x200000 /* Enable project quota
1134 						  * enforcement */
1135 #define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
1136 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
1137 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
1138 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
1139 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
1140 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
1141 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
1142 #define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
1143 #define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
1144 
1145 /*
1146  * Mount flags set either automatically (could not be set by mount option)
1147  * based on per file system feature or property or in special cases such as
1148  * distinguishing between explicit mount option definition and default.
1149  */
1150 #define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1151 						      specified delalloc */
1152 #define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1153 						      size of blocksize * 8
1154 						      blocks */
1155 #define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1156 						      file systems */
1157 
1158 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
1159 						specified journal checksum */
1160 
1161 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1162 						~EXT4_MOUNT_##opt
1163 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1164 						EXT4_MOUNT_##opt
1165 #define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1166 					 EXT4_MOUNT_##opt)
1167 
1168 #define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1169 						~EXT4_MOUNT2_##opt
1170 #define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1171 						EXT4_MOUNT2_##opt
1172 #define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1173 					 EXT4_MOUNT2_##opt)
1174 
1175 #define ext4_test_and_set_bit		__test_and_set_bit_le
1176 #define ext4_set_bit			__set_bit_le
1177 #define ext4_set_bit_atomic		ext2_set_bit_atomic
1178 #define ext4_test_and_clear_bit		__test_and_clear_bit_le
1179 #define ext4_clear_bit			__clear_bit_le
1180 #define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1181 #define ext4_test_bit			test_bit_le
1182 #define ext4_find_next_zero_bit		find_next_zero_bit_le
1183 #define ext4_find_next_bit		find_next_bit_le
1184 
1185 extern void ext4_set_bits(void *bm, int cur, int len);
1186 
1187 /*
1188  * Maximal mount counts between two filesystem checks
1189  */
1190 #define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1191 #define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1192 
1193 /*
1194  * Behaviour when detecting errors
1195  */
1196 #define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1197 #define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1198 #define EXT4_ERRORS_PANIC		3	/* Panic */
1199 #define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1200 
1201 /* Metadata checksum algorithm codes */
1202 #define EXT4_CRC32C_CHKSUM		1
1203 
1204 /*
1205  * Structure of the super block
1206  */
1207 struct ext4_super_block {
1208 /*00*/	__le32	s_inodes_count;		/* Inodes count */
1209 	__le32	s_blocks_count_lo;	/* Blocks count */
1210 	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1211 	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1212 /*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1213 	__le32	s_first_data_block;	/* First Data Block */
1214 	__le32	s_log_block_size;	/* Block size */
1215 	__le32	s_log_cluster_size;	/* Allocation cluster size */
1216 /*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1217 	__le32	s_clusters_per_group;	/* # Clusters per group */
1218 	__le32	s_inodes_per_group;	/* # Inodes per group */
1219 	__le32	s_mtime;		/* Mount time */
1220 /*30*/	__le32	s_wtime;		/* Write time */
1221 	__le16	s_mnt_count;		/* Mount count */
1222 	__le16	s_max_mnt_count;	/* Maximal mount count */
1223 	__le16	s_magic;		/* Magic signature */
1224 	__le16	s_state;		/* File system state */
1225 	__le16	s_errors;		/* Behaviour when detecting errors */
1226 	__le16	s_minor_rev_level;	/* minor revision level */
1227 /*40*/	__le32	s_lastcheck;		/* time of last check */
1228 	__le32	s_checkinterval;	/* max. time between checks */
1229 	__le32	s_creator_os;		/* OS */
1230 	__le32	s_rev_level;		/* Revision level */
1231 /*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1232 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1233 	/*
1234 	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1235 	 *
1236 	 * Note: the difference between the compatible feature set and
1237 	 * the incompatible feature set is that if there is a bit set
1238 	 * in the incompatible feature set that the kernel doesn't
1239 	 * know about, it should refuse to mount the filesystem.
1240 	 *
1241 	 * e2fsck's requirements are more strict; if it doesn't know
1242 	 * about a feature in either the compatible or incompatible
1243 	 * feature set, it must abort and not try to meddle with
1244 	 * things it doesn't understand...
1245 	 */
1246 	__le32	s_first_ino;		/* First non-reserved inode */
1247 	__le16  s_inode_size;		/* size of inode structure */
1248 	__le16	s_block_group_nr;	/* block group # of this superblock */
1249 	__le32	s_feature_compat;	/* compatible feature set */
1250 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1251 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1252 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1253 /*78*/	char	s_volume_name[16];	/* volume name */
1254 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
1255 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1256 	/*
1257 	 * Performance hints.  Directory preallocation should only
1258 	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1259 	 */
1260 	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1261 	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1262 	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1263 	/*
1264 	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1265 	 */
1266 /*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1267 /*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1268 	__le32	s_journal_dev;		/* device number of journal file */
1269 	__le32	s_last_orphan;		/* start of list of inodes to delete */
1270 	__le32	s_hash_seed[4];		/* HTREE hash seed */
1271 	__u8	s_def_hash_version;	/* Default hash version to use */
1272 	__u8	s_jnl_backup_type;
1273 	__le16  s_desc_size;		/* size of group descriptor */
1274 /*100*/	__le32	s_default_mount_opts;
1275 	__le32	s_first_meta_bg;	/* First metablock block group */
1276 	__le32	s_mkfs_time;		/* When the filesystem was created */
1277 	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1278 	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1279 /*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1280 	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1281 	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1282 	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1283 	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1284 	__le32	s_flags;		/* Miscellaneous flags */
1285 	__le16  s_raid_stride;		/* RAID stride */
1286 	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1287 	__le64  s_mmp_block;            /* Block for multi-mount protection */
1288 	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1289 	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1290 	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1291 	__u8	s_encryption_level;	/* versioning level for encryption */
1292 	__u8	s_reserved_pad;		/* Padding to next 32bits */
1293 	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1294 	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1295 	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1296 	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1297 					      snapshot's future use */
1298 	__le32	s_snapshot_list;	/* inode number of the head of the
1299 					   on-disk snapshot list */
1300 #define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1301 	__le32	s_error_count;		/* number of fs errors */
1302 	__le32	s_first_error_time;	/* first time an error happened */
1303 	__le32	s_first_error_ino;	/* inode involved in first error */
1304 	__le64	s_first_error_block;	/* block involved of first error */
1305 	__u8	s_first_error_func[32] __nonstring;	/* function where the error happened */
1306 	__le32	s_first_error_line;	/* line number where error happened */
1307 	__le32	s_last_error_time;	/* most recent time of an error */
1308 	__le32	s_last_error_ino;	/* inode involved in last error */
1309 	__le32	s_last_error_line;	/* line number where error happened */
1310 	__le64	s_last_error_block;	/* block involved of last error */
1311 	__u8	s_last_error_func[32] __nonstring;	/* function where the error happened */
1312 #define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1313 	__u8	s_mount_opts[64];
1314 	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1315 	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1316 	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1317 	__le32	s_backup_bgs[2];	/* groups with sparse_super2 SBs */
1318 	__u8	s_encrypt_algos[4];	/* Encryption algorithms in use  */
1319 	__u8	s_encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
1320 	__le32	s_lpf_ino;		/* Location of the lost+found inode */
1321 	__le32	s_prj_quota_inum;	/* inode for tracking project quota */
1322 	__le32	s_checksum_seed;	/* crc32c(uuid) if csum_seed set */
1323 	__u8	s_wtime_hi;
1324 	__u8	s_mtime_hi;
1325 	__u8	s_mkfs_time_hi;
1326 	__u8	s_lastcheck_hi;
1327 	__u8	s_first_error_time_hi;
1328 	__u8	s_last_error_time_hi;
1329 	__u8	s_pad[2];
1330 	__le32	s_reserved[96];		/* Padding to the end of the block */
1331 	__le32	s_checksum;		/* crc32c(superblock) */
1332 };
1333 
1334 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1335 
1336 #ifdef __KERNEL__
1337 
1338 /*
1339  * run-time mount flags
1340  */
1341 #define EXT4_MF_MNTDIR_SAMPLED		0x0001
1342 #define EXT4_MF_FS_ABORTED		0x0002	/* Fatal error detected */
1343 #define EXT4_MF_TEST_DUMMY_ENCRYPTION	0x0004
1344 
1345 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1346 #define DUMMY_ENCRYPTION_ENABLED(sbi) (unlikely((sbi)->s_mount_flags & \
1347 						EXT4_MF_TEST_DUMMY_ENCRYPTION))
1348 #else
1349 #define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
1350 #endif
1351 
1352 /* Number of quota types we support */
1353 #define EXT4_MAXQUOTAS 3
1354 
1355 /*
1356  * fourth extended-fs super-block data in memory
1357  */
1358 struct ext4_sb_info {
1359 	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1360 	unsigned long s_inodes_per_block;/* Number of inodes per block */
1361 	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1362 	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1363 	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1364 	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1365 	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1366 	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1367 	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1368 	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1369 	unsigned long s_overhead;  /* # of fs overhead clusters */
1370 	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1371 	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1372 	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1373 	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1374 	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1375 	struct buffer_head * __rcu *s_group_desc;
1376 	unsigned int s_mount_opt;
1377 	unsigned int s_mount_opt2;
1378 	unsigned int s_mount_flags;
1379 	unsigned int s_def_mount_opt;
1380 	ext4_fsblk_t s_sb_block;
1381 	atomic64_t s_resv_clusters;
1382 	kuid_t s_resuid;
1383 	kgid_t s_resgid;
1384 	unsigned short s_mount_state;
1385 	unsigned short s_pad;
1386 	int s_addr_per_block_bits;
1387 	int s_desc_per_block_bits;
1388 	int s_inode_size;
1389 	int s_first_ino;
1390 	unsigned int s_inode_readahead_blks;
1391 	unsigned int s_inode_goal;
1392 	u32 s_hash_seed[4];
1393 	int s_def_hash_version;
1394 	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1395 	struct percpu_counter s_freeclusters_counter;
1396 	struct percpu_counter s_freeinodes_counter;
1397 	struct percpu_counter s_dirs_counter;
1398 	struct percpu_counter s_dirtyclusters_counter;
1399 	struct blockgroup_lock *s_blockgroup_lock;
1400 	struct proc_dir_entry *s_proc;
1401 	struct kobject s_kobj;
1402 	struct completion s_kobj_unregister;
1403 	struct super_block *s_sb;
1404 
1405 	/* Journaling */
1406 	struct journal_s *s_journal;
1407 	struct list_head s_orphan;
1408 	struct mutex s_orphan_lock;
1409 	unsigned long s_ext4_flags;		/* Ext4 superblock flags */
1410 	unsigned long s_commit_interval;
1411 	u32 s_max_batch_time;
1412 	u32 s_min_batch_time;
1413 	struct block_device *journal_bdev;
1414 #ifdef CONFIG_QUOTA
1415 	/* Names of quota files with journalled quota */
1416 	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
1417 	int s_jquota_fmt;			/* Format of quota to use */
1418 #endif
1419 	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1420 	struct ext4_system_blocks __rcu *system_blks;
1421 
1422 #ifdef EXTENTS_STATS
1423 	/* ext4 extents stats */
1424 	unsigned long s_ext_min;
1425 	unsigned long s_ext_max;
1426 	unsigned long s_depth_max;
1427 	spinlock_t s_ext_stats_lock;
1428 	unsigned long s_ext_blocks;
1429 	unsigned long s_ext_extents;
1430 #endif
1431 
1432 	/* for buddy allocator */
1433 	struct ext4_group_info ** __rcu *s_group_info;
1434 	struct inode *s_buddy_cache;
1435 	spinlock_t s_md_lock;
1436 	unsigned short *s_mb_offsets;
1437 	unsigned int *s_mb_maxs;
1438 	unsigned int s_group_info_size;
1439 	unsigned int s_mb_free_pending;
1440 	struct list_head s_freed_data_list;	/* List of blocks to be freed
1441 						   after commit completed */
1442 
1443 	/* tunables */
1444 	unsigned long s_stripe;
1445 	unsigned int s_mb_stream_request;
1446 	unsigned int s_mb_max_to_scan;
1447 	unsigned int s_mb_min_to_scan;
1448 	unsigned int s_mb_stats;
1449 	unsigned int s_mb_order2_reqs;
1450 	unsigned int s_mb_group_prealloc;
1451 	unsigned int s_max_dir_size_kb;
1452 	/* where last allocation was done - for stream allocation */
1453 	unsigned long s_mb_last_group;
1454 	unsigned long s_mb_last_start;
1455 
1456 	/* stats for buddy allocator */
1457 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1458 	atomic_t s_bal_success;	/* we found long enough chunks */
1459 	atomic_t s_bal_allocated;	/* in blocks */
1460 	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1461 	atomic_t s_bal_goals;	/* goal hits */
1462 	atomic_t s_bal_breaks;	/* too long searches */
1463 	atomic_t s_bal_2orders;	/* 2^order hits */
1464 	spinlock_t s_bal_lock;
1465 	unsigned long s_mb_buddies_generated;
1466 	unsigned long long s_mb_generation_time;
1467 	atomic_t s_mb_lost_chunks;
1468 	atomic_t s_mb_preallocated;
1469 	atomic_t s_mb_discarded;
1470 	atomic_t s_lock_busy;
1471 
1472 	/* locality groups */
1473 	struct ext4_locality_group __percpu *s_locality_groups;
1474 
1475 	/* for write statistics */
1476 	unsigned long s_sectors_written_start;
1477 	u64 s_kbytes_written;
1478 
1479 	/* the size of zero-out chunk */
1480 	unsigned int s_extent_max_zeroout_kb;
1481 
1482 	unsigned int s_log_groups_per_flex;
1483 	struct flex_groups * __rcu *s_flex_groups;
1484 	ext4_group_t s_flex_groups_allocated;
1485 
1486 	/* workqueue for reserved extent conversions (buffered io) */
1487 	struct workqueue_struct *rsv_conversion_wq;
1488 
1489 	/* timer for periodic error stats printing */
1490 	struct timer_list s_err_report;
1491 
1492 	/* Lazy inode table initialization info */
1493 	struct ext4_li_request *s_li_request;
1494 	/* Wait multiplier for lazy initialization thread */
1495 	unsigned int s_li_wait_mult;
1496 
1497 	/* Kernel thread for multiple mount protection */
1498 	struct task_struct *s_mmp_tsk;
1499 
1500 	/* record the last minlen when FITRIM is called. */
1501 	atomic_t s_last_trim_minblks;
1502 
1503 	/* Reference to checksum algorithm driver via cryptoapi */
1504 	struct crypto_shash *s_chksum_driver;
1505 
1506 	/* Precomputed FS UUID checksum for seeding other checksums */
1507 	__u32 s_csum_seed;
1508 
1509 	/* Reclaim extents from extent status tree */
1510 	struct shrinker s_es_shrinker;
1511 	struct list_head s_es_list;	/* List of inodes with reclaimable extents */
1512 	long s_es_nr_inode;
1513 	struct ext4_es_stats s_es_stats;
1514 	struct mb_cache *s_ea_block_cache;
1515 	struct mb_cache *s_ea_inode_cache;
1516 	spinlock_t s_es_lock ____cacheline_aligned_in_smp;
1517 
1518 	/* Ratelimit ext4 messages. */
1519 	struct ratelimit_state s_err_ratelimit_state;
1520 	struct ratelimit_state s_warning_ratelimit_state;
1521 	struct ratelimit_state s_msg_ratelimit_state;
1522 
1523 	/*
1524 	 * Barrier between writepages ops and changing any inode's JOURNAL_DATA
1525 	 * or EXTENTS flag.
1526 	 */
1527 	struct percpu_rw_semaphore s_writepages_rwsem;
1528 	struct dax_device *s_daxdev;
1529 };
1530 
EXT4_SB(struct super_block * sb)1531 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1532 {
1533 	return sb->s_fs_info;
1534 }
EXT4_I(struct inode * inode)1535 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1536 {
1537 	return container_of(inode, struct ext4_inode_info, vfs_inode);
1538 }
1539 
ext4_valid_inum(struct super_block * sb,unsigned long ino)1540 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1541 {
1542 	return ino == EXT4_ROOT_INO ||
1543 		(ino >= EXT4_FIRST_INO(sb) &&
1544 		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1545 }
1546 
1547 /*
1548  * Returns: sbi->field[index]
1549  * Used to access an array element from the following sbi fields which require
1550  * rcu protection to avoid dereferencing an invalid pointer due to reassignment
1551  * - s_group_desc
1552  * - s_group_info
1553  * - s_flex_group
1554  */
1555 #define sbi_array_rcu_deref(sbi, field, index)				   \
1556 ({									   \
1557 	typeof(*((sbi)->field)) _v;					   \
1558 	rcu_read_lock();						   \
1559 	_v = ((typeof(_v)*)rcu_dereference((sbi)->field))[index];	   \
1560 	rcu_read_unlock();						   \
1561 	_v;								   \
1562 })
1563 
1564 /*
1565  * Inode dynamic state flags
1566  */
1567 enum {
1568 	EXT4_STATE_JDATA,		/* journaled data exists */
1569 	EXT4_STATE_NEW,			/* inode is newly created */
1570 	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1571 	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1572 	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1573 	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1574 	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1575 	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1576 	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1577 	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1578 	EXT4_STATE_LUSTRE_EA_INODE,	/* Lustre-style ea_inode */
1579 };
1580 
1581 #define EXT4_INODE_BIT_FNS(name, field, offset)				\
1582 static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1583 {									\
1584 	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1585 }									\
1586 static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1587 {									\
1588 	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1589 }									\
1590 static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1591 {									\
1592 	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1593 }
1594 
1595 /* Add these declarations here only so that these functions can be
1596  * found by name.  Otherwise, they are very hard to locate. */
1597 static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1598 static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1599 static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1600 EXT4_INODE_BIT_FNS(flag, flags, 0)
1601 
1602 /* Add these declarations here only so that these functions can be
1603  * found by name.  Otherwise, they are very hard to locate. */
1604 static inline int ext4_test_inode_state(struct inode *inode, int bit);
1605 static inline void ext4_set_inode_state(struct inode *inode, int bit);
1606 static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1607 #if (BITS_PER_LONG < 64)
1608 EXT4_INODE_BIT_FNS(state, state_flags, 0)
1609 
ext4_clear_state_flags(struct ext4_inode_info * ei)1610 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1611 {
1612 	(ei)->i_state_flags = 0;
1613 }
1614 #else
1615 EXT4_INODE_BIT_FNS(state, flags, 32)
1616 
ext4_clear_state_flags(struct ext4_inode_info * ei)1617 static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1618 {
1619 	/* We depend on the fact that callers will set i_flags */
1620 }
1621 #endif
1622 #else
1623 /* Assume that user mode programs are passing in an ext4fs superblock, not
1624  * a kernel struct super_block.  This will allow us to call the feature-test
1625  * macros from user land. */
1626 #define EXT4_SB(sb)	(sb)
1627 #endif
1628 
1629 /*
1630  * Returns true if the inode is inode is encrypted
1631  */
1632 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1633 
1634 /*
1635  * Codes for operating systems
1636  */
1637 #define EXT4_OS_LINUX		0
1638 #define EXT4_OS_HURD		1
1639 #define EXT4_OS_MASIX		2
1640 #define EXT4_OS_FREEBSD		3
1641 #define EXT4_OS_LITES		4
1642 
1643 /*
1644  * Revision levels
1645  */
1646 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1647 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1648 
1649 #define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1650 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1651 
1652 #define EXT4_GOOD_OLD_INODE_SIZE 128
1653 
1654 /*
1655  * Feature set definitions
1656  */
1657 
1658 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1659 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1660 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1661 #define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1662 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1663 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1664 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
1665 
1666 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1667 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1668 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1669 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1670 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1671 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1672 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1673 #define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1674 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1675 /*
1676  * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1677  * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1678  * all other data structures' checksums.  However, the METADATA_CSUM and
1679  * GDT_CSUM bits are mutually exclusive.
1680  */
1681 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1682 #define EXT4_FEATURE_RO_COMPAT_READONLY		0x1000
1683 #define EXT4_FEATURE_RO_COMPAT_PROJECT		0x2000
1684 
1685 #define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1686 #define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1687 #define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1688 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1689 #define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1690 #define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1691 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1692 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1693 #define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1694 #define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1695 #define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1696 #define EXT4_FEATURE_INCOMPAT_CSUM_SEED		0x2000
1697 #define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1698 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1699 #define EXT4_FEATURE_INCOMPAT_ENCRYPT		0x10000
1700 
1701 extern void ext4_update_dynamic_rev(struct super_block *sb);
1702 
1703 #define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
1704 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1705 { \
1706 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1707 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname)) != 0); \
1708 } \
1709 static inline void ext4_set_feature_##name(struct super_block *sb) \
1710 { \
1711 	ext4_update_dynamic_rev(sb); \
1712 	EXT4_SB(sb)->s_es->s_feature_compat |= \
1713 		cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1714 } \
1715 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1716 { \
1717 	EXT4_SB(sb)->s_es->s_feature_compat &= \
1718 		~cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
1719 }
1720 
1721 #define EXT4_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1722 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1723 { \
1724 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1725 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname)) != 0); \
1726 } \
1727 static inline void ext4_set_feature_##name(struct super_block *sb) \
1728 { \
1729 	ext4_update_dynamic_rev(sb); \
1730 	EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
1731 		cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1732 } \
1733 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1734 { \
1735 	EXT4_SB(sb)->s_es->s_feature_ro_compat &= \
1736 		~cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
1737 }
1738 
1739 #define EXT4_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1740 static inline bool ext4_has_feature_##name(struct super_block *sb) \
1741 { \
1742 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1743 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname)) != 0); \
1744 } \
1745 static inline void ext4_set_feature_##name(struct super_block *sb) \
1746 { \
1747 	ext4_update_dynamic_rev(sb); \
1748 	EXT4_SB(sb)->s_es->s_feature_incompat |= \
1749 		cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1750 } \
1751 static inline void ext4_clear_feature_##name(struct super_block *sb) \
1752 { \
1753 	EXT4_SB(sb)->s_es->s_feature_incompat &= \
1754 		~cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
1755 }
1756 
EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,DIR_PREALLOC)1757 EXT4_FEATURE_COMPAT_FUNCS(dir_prealloc,		DIR_PREALLOC)
1758 EXT4_FEATURE_COMPAT_FUNCS(imagic_inodes,	IMAGIC_INODES)
1759 EXT4_FEATURE_COMPAT_FUNCS(journal,		HAS_JOURNAL)
1760 EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
1761 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
1762 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
1763 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
1764 
1765 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
1766 EXT4_FEATURE_RO_COMPAT_FUNCS(large_file,	LARGE_FILE)
1767 EXT4_FEATURE_RO_COMPAT_FUNCS(btree_dir,		BTREE_DIR)
1768 EXT4_FEATURE_RO_COMPAT_FUNCS(huge_file,		HUGE_FILE)
1769 EXT4_FEATURE_RO_COMPAT_FUNCS(gdt_csum,		GDT_CSUM)
1770 EXT4_FEATURE_RO_COMPAT_FUNCS(dir_nlink,		DIR_NLINK)
1771 EXT4_FEATURE_RO_COMPAT_FUNCS(extra_isize,	EXTRA_ISIZE)
1772 EXT4_FEATURE_RO_COMPAT_FUNCS(quota,		QUOTA)
1773 EXT4_FEATURE_RO_COMPAT_FUNCS(bigalloc,		BIGALLOC)
1774 EXT4_FEATURE_RO_COMPAT_FUNCS(metadata_csum,	METADATA_CSUM)
1775 EXT4_FEATURE_RO_COMPAT_FUNCS(readonly,		READONLY)
1776 EXT4_FEATURE_RO_COMPAT_FUNCS(project,		PROJECT)
1777 
1778 EXT4_FEATURE_INCOMPAT_FUNCS(compression,	COMPRESSION)
1779 EXT4_FEATURE_INCOMPAT_FUNCS(filetype,		FILETYPE)
1780 EXT4_FEATURE_INCOMPAT_FUNCS(journal_needs_recovery,	RECOVER)
1781 EXT4_FEATURE_INCOMPAT_FUNCS(journal_dev,	JOURNAL_DEV)
1782 EXT4_FEATURE_INCOMPAT_FUNCS(meta_bg,		META_BG)
1783 EXT4_FEATURE_INCOMPAT_FUNCS(extents,		EXTENTS)
1784 EXT4_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
1785 EXT4_FEATURE_INCOMPAT_FUNCS(mmp,		MMP)
1786 EXT4_FEATURE_INCOMPAT_FUNCS(flex_bg,		FLEX_BG)
1787 EXT4_FEATURE_INCOMPAT_FUNCS(ea_inode,		EA_INODE)
1788 EXT4_FEATURE_INCOMPAT_FUNCS(dirdata,		DIRDATA)
1789 EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed,		CSUM_SEED)
1790 EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		LARGEDIR)
1791 EXT4_FEATURE_INCOMPAT_FUNCS(inline_data,	INLINE_DATA)
1792 EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		ENCRYPT)
1793 
1794 #define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1795 #define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1796 					 EXT4_FEATURE_INCOMPAT_META_BG)
1797 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1798 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1799 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1800 
1801 #define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1802 #define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1803 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1804 					 EXT4_FEATURE_INCOMPAT_META_BG)
1805 #define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1806 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1807 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1808 
1809 #define EXT4_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1810 #define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1811 					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1812 					 EXT4_FEATURE_INCOMPAT_META_BG| \
1813 					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1814 					 EXT4_FEATURE_INCOMPAT_64BIT| \
1815 					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1816 					 EXT4_FEATURE_INCOMPAT_EA_INODE| \
1817 					 EXT4_FEATURE_INCOMPAT_MMP | \
1818 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
1819 					 EXT4_FEATURE_INCOMPAT_ENCRYPT | \
1820 					 EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
1821 					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
1822 #define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1823 					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1824 					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1825 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1826 					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1827 					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1828 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1829 					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1830 					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1831 					 EXT4_FEATURE_RO_COMPAT_QUOTA |\
1832 					 EXT4_FEATURE_RO_COMPAT_PROJECT)
1833 
1834 #define EXTN_FEATURE_FUNCS(ver) \
1835 static inline bool ext4_has_unknown_ext##ver##_compat_features(struct super_block *sb) \
1836 { \
1837 	return ((EXT4_SB(sb)->s_es->s_feature_compat & \
1838 		cpu_to_le32(~EXT##ver##_FEATURE_COMPAT_SUPP)) != 0); \
1839 } \
1840 static inline bool ext4_has_unknown_ext##ver##_ro_compat_features(struct super_block *sb) \
1841 { \
1842 	return ((EXT4_SB(sb)->s_es->s_feature_ro_compat & \
1843 		cpu_to_le32(~EXT##ver##_FEATURE_RO_COMPAT_SUPP)) != 0); \
1844 } \
1845 static inline bool ext4_has_unknown_ext##ver##_incompat_features(struct super_block *sb) \
1846 { \
1847 	return ((EXT4_SB(sb)->s_es->s_feature_incompat & \
1848 		cpu_to_le32(~EXT##ver##_FEATURE_INCOMPAT_SUPP)) != 0); \
1849 }
1850 
1851 EXTN_FEATURE_FUNCS(2)
1852 EXTN_FEATURE_FUNCS(3)
1853 EXTN_FEATURE_FUNCS(4)
1854 
1855 static inline bool ext4_has_compat_features(struct super_block *sb)
1856 {
1857 	return (EXT4_SB(sb)->s_es->s_feature_compat != 0);
1858 }
ext4_has_ro_compat_features(struct super_block * sb)1859 static inline bool ext4_has_ro_compat_features(struct super_block *sb)
1860 {
1861 	return (EXT4_SB(sb)->s_es->s_feature_ro_compat != 0);
1862 }
ext4_has_incompat_features(struct super_block * sb)1863 static inline bool ext4_has_incompat_features(struct super_block *sb)
1864 {
1865 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
1866 }
1867 
1868 /*
1869  * Superblock flags
1870  */
1871 #define EXT4_FLAGS_RESIZING	0
1872 #define EXT4_FLAGS_SHUTDOWN	1
1873 
ext4_forced_shutdown(struct ext4_sb_info * sbi)1874 static inline int ext4_forced_shutdown(struct ext4_sb_info *sbi)
1875 {
1876 	return test_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
1877 }
1878 
1879 
1880 /*
1881  * Default values for user and/or group using reserved blocks
1882  */
1883 #define	EXT4_DEF_RESUID		0
1884 #define	EXT4_DEF_RESGID		0
1885 
1886 /*
1887  * Default project ID
1888  */
1889 #define	EXT4_DEF_PROJID		0
1890 
1891 #define EXT4_DEF_INODE_READAHEAD_BLKS	32
1892 
1893 /*
1894  * Default mount options
1895  */
1896 #define EXT4_DEFM_DEBUG		0x0001
1897 #define EXT4_DEFM_BSDGROUPS	0x0002
1898 #define EXT4_DEFM_XATTR_USER	0x0004
1899 #define EXT4_DEFM_ACL		0x0008
1900 #define EXT4_DEFM_UID16		0x0010
1901 #define EXT4_DEFM_JMODE		0x0060
1902 #define EXT4_DEFM_JMODE_DATA	0x0020
1903 #define EXT4_DEFM_JMODE_ORDERED	0x0040
1904 #define EXT4_DEFM_JMODE_WBACK	0x0060
1905 #define EXT4_DEFM_NOBARRIER	0x0100
1906 #define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1907 #define EXT4_DEFM_DISCARD	0x0400
1908 #define EXT4_DEFM_NODELALLOC	0x0800
1909 
1910 /*
1911  * Default journal batch times
1912  */
1913 #define EXT4_DEF_MIN_BATCH_TIME	0
1914 #define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1915 
1916 /*
1917  * Minimum number of groups in a flexgroup before we separate out
1918  * directories into the first block group of a flexgroup
1919  */
1920 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1921 
1922 /*
1923  * Structure of a directory entry
1924  */
1925 #define EXT4_NAME_LEN 255
1926 
1927 struct ext4_dir_entry {
1928 	__le32	inode;			/* Inode number */
1929 	__le16	rec_len;		/* Directory entry length */
1930 	__le16	name_len;		/* Name length */
1931 	char	name[EXT4_NAME_LEN];	/* File name */
1932 };
1933 
1934 /*
1935  * The new version of the directory entry.  Since EXT4 structures are
1936  * stored in intel byte order, and the name_len field could never be
1937  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1938  * file_type field.
1939  */
1940 struct ext4_dir_entry_2 {
1941 	__le32	inode;			/* Inode number */
1942 	__le16	rec_len;		/* Directory entry length */
1943 	__u8	name_len;		/* Name length */
1944 	__u8	file_type;
1945 	char	name[EXT4_NAME_LEN];	/* File name */
1946 };
1947 
1948 /*
1949  * This is a bogus directory entry at the end of each leaf block that
1950  * records checksums.
1951  */
1952 struct ext4_dir_entry_tail {
1953 	__le32	det_reserved_zero1;	/* Pretend to be unused */
1954 	__le16	det_rec_len;		/* 12 */
1955 	__u8	det_reserved_zero2;	/* Zero name length */
1956 	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1957 	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1958 };
1959 
1960 #define EXT4_DIRENT_TAIL(block, blocksize) \
1961 	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1962 					((blocksize) - \
1963 					 sizeof(struct ext4_dir_entry_tail))))
1964 
1965 /*
1966  * Ext4 directory file types.  Only the low 3 bits are used.  The
1967  * other bits are reserved for now.
1968  */
1969 #define EXT4_FT_UNKNOWN		0
1970 #define EXT4_FT_REG_FILE	1
1971 #define EXT4_FT_DIR		2
1972 #define EXT4_FT_CHRDEV		3
1973 #define EXT4_FT_BLKDEV		4
1974 #define EXT4_FT_FIFO		5
1975 #define EXT4_FT_SOCK		6
1976 #define EXT4_FT_SYMLINK		7
1977 
1978 #define EXT4_FT_MAX		8
1979 
1980 #define EXT4_FT_DIR_CSUM	0xDE
1981 
1982 /*
1983  * EXT4_DIR_PAD defines the directory entries boundaries
1984  *
1985  * NOTE: It must be a multiple of 4
1986  */
1987 #define EXT4_DIR_PAD			4
1988 #define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1989 #define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1990 					 ~EXT4_DIR_ROUND)
1991 #define EXT4_MAX_REC_LEN		((1<<16)-1)
1992 
1993 /*
1994  * If we ever get support for fs block sizes > page_size, we'll need
1995  * to remove the #if statements in the next two functions...
1996  */
1997 static inline unsigned int
ext4_rec_len_from_disk(__le16 dlen,unsigned blocksize)1998 ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1999 {
2000 	unsigned len = le16_to_cpu(dlen);
2001 
2002 #if (PAGE_SIZE >= 65536)
2003 	if (len == EXT4_MAX_REC_LEN || len == 0)
2004 		return blocksize;
2005 	return (len & 65532) | ((len & 3) << 16);
2006 #else
2007 	return len;
2008 #endif
2009 }
2010 
ext4_rec_len_to_disk(unsigned len,unsigned blocksize)2011 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
2012 {
2013 	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
2014 		BUG();
2015 #if (PAGE_SIZE >= 65536)
2016 	if (len < 65536)
2017 		return cpu_to_le16(len);
2018 	if (len == blocksize) {
2019 		if (blocksize == 65536)
2020 			return cpu_to_le16(EXT4_MAX_REC_LEN);
2021 		else
2022 			return cpu_to_le16(0);
2023 	}
2024 	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
2025 #else
2026 	return cpu_to_le16(len);
2027 #endif
2028 }
2029 
2030 /*
2031  * Hash Tree Directory indexing
2032  * (c) Daniel Phillips, 2001
2033  */
2034 
2035 #define is_dx(dir) (ext4_has_feature_dir_index((dir)->i_sb) && \
2036 		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
2037 #define EXT4_DIR_LINK_MAX(dir) unlikely((dir)->i_nlink >= EXT4_LINK_MAX && \
2038 		    !(ext4_has_feature_dir_nlink((dir)->i_sb) && is_dx(dir)))
2039 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
2040 
2041 /* Legal values for the dx_root hash_version field: */
2042 
2043 #define DX_HASH_LEGACY			0
2044 #define DX_HASH_HALF_MD4		1
2045 #define DX_HASH_TEA			2
2046 #define DX_HASH_LEGACY_UNSIGNED		3
2047 #define DX_HASH_HALF_MD4_UNSIGNED	4
2048 #define DX_HASH_TEA_UNSIGNED		5
2049 
ext4_chksum(struct ext4_sb_info * sbi,u32 crc,const void * address,unsigned int length)2050 static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
2051 			      const void *address, unsigned int length)
2052 {
2053 	struct {
2054 		struct shash_desc shash;
2055 		char ctx[4];
2056 	} desc;
2057 
2058 	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
2059 
2060 	desc.shash.tfm = sbi->s_chksum_driver;
2061 	desc.shash.flags = 0;
2062 	*(u32 *)desc.ctx = crc;
2063 
2064 	BUG_ON(crypto_shash_update(&desc.shash, address, length));
2065 
2066 	return *(u32 *)desc.ctx;
2067 }
2068 
2069 #ifdef __KERNEL__
2070 
2071 /* hash info structure used by the directory hash */
2072 struct dx_hash_info
2073 {
2074 	u32		hash;
2075 	u32		minor_hash;
2076 	int		hash_version;
2077 	u32		*seed;
2078 };
2079 
2080 
2081 /* 32 and 64 bit signed EOF for dx directories */
2082 #define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
2083 #define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
2084 
2085 
2086 /*
2087  * Control parameters used by ext4_htree_next_block
2088  */
2089 #define HASH_NB_ALWAYS		1
2090 
2091 struct ext4_filename {
2092 	const struct qstr *usr_fname;
2093 	struct fscrypt_str disk_name;
2094 	struct dx_hash_info hinfo;
2095 #ifdef CONFIG_EXT4_FS_ENCRYPTION
2096 	struct fscrypt_str crypto_buf;
2097 #endif
2098 };
2099 
2100 #define fname_name(p) ((p)->disk_name.name)
2101 #define fname_len(p)  ((p)->disk_name.len)
2102 
2103 /*
2104  * Describe an inode's exact location on disk and in memory
2105  */
2106 struct ext4_iloc
2107 {
2108 	struct buffer_head *bh;
2109 	unsigned long offset;
2110 	ext4_group_t block_group;
2111 };
2112 
ext4_raw_inode(struct ext4_iloc * iloc)2113 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
2114 {
2115 	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
2116 }
2117 
ext4_is_quota_file(struct inode * inode)2118 static inline bool ext4_is_quota_file(struct inode *inode)
2119 {
2120 	return IS_NOQUOTA(inode) &&
2121 	       !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL);
2122 }
2123 
2124 /*
2125  * This structure is stuffed into the struct file's private_data field
2126  * for directories.  It is where we put information so that we can do
2127  * readdir operations in hash tree order.
2128  */
2129 struct dir_private_info {
2130 	struct rb_root	root;
2131 	struct rb_node	*curr_node;
2132 	struct fname	*extra_fname;
2133 	loff_t		last_pos;
2134 	__u32		curr_hash;
2135 	__u32		curr_minor_hash;
2136 	__u32		next_hash;
2137 };
2138 
2139 /* calculate the first block number of the group */
2140 static inline ext4_fsblk_t
ext4_group_first_block_no(struct super_block * sb,ext4_group_t group_no)2141 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
2142 {
2143 	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
2144 		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
2145 }
2146 
2147 /*
2148  * Special error return code only used by dx_probe() and its callers.
2149  */
2150 #define ERR_BAD_DX_DIR	(-(MAX_ERRNO - 1))
2151 
2152 /* htree levels for ext4 */
2153 #define	EXT4_HTREE_LEVEL_COMPAT	2
2154 #define	EXT4_HTREE_LEVEL	3
2155 
ext4_dir_htree_level(struct super_block * sb)2156 static inline int ext4_dir_htree_level(struct super_block *sb)
2157 {
2158 	return ext4_has_feature_largedir(sb) ?
2159 		EXT4_HTREE_LEVEL : EXT4_HTREE_LEVEL_COMPAT;
2160 }
2161 
2162 /*
2163  * Timeout and state flag for lazy initialization inode thread.
2164  */
2165 #define EXT4_DEF_LI_WAIT_MULT			10
2166 #define EXT4_DEF_LI_MAX_START_DELAY		5
2167 #define EXT4_LAZYINIT_QUIT			0x0001
2168 #define EXT4_LAZYINIT_RUNNING			0x0002
2169 
2170 /*
2171  * Lazy inode table initialization info
2172  */
2173 struct ext4_lazy_init {
2174 	unsigned long		li_state;
2175 	struct list_head	li_request_list;
2176 	struct mutex		li_list_mtx;
2177 };
2178 
2179 struct ext4_li_request {
2180 	struct super_block	*lr_super;
2181 	struct ext4_sb_info	*lr_sbi;
2182 	ext4_group_t		lr_next_group;
2183 	struct list_head	lr_request;
2184 	unsigned long		lr_next_sched;
2185 	unsigned long		lr_timeout;
2186 };
2187 
2188 struct ext4_features {
2189 	struct kobject f_kobj;
2190 	struct completion f_kobj_unregister;
2191 };
2192 
2193 /*
2194  * This structure will be used for multiple mount protection. It will be
2195  * written into the block number saved in the s_mmp_block field in the
2196  * superblock. Programs that check MMP should assume that if
2197  * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
2198  * to use the filesystem, regardless of how old the timestamp is.
2199  */
2200 #define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
2201 #define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
2202 #define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
2203 #define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
2204 
2205 struct mmp_struct {
2206 	__le32	mmp_magic;		/* Magic number for MMP */
2207 	__le32	mmp_seq;		/* Sequence no. updated periodically */
2208 
2209 	/*
2210 	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
2211 	 * purposes and do not affect the correctness of the algorithm
2212 	 */
2213 	__le64	mmp_time;		/* Time last updated */
2214 	char	mmp_nodename[64];	/* Node which last updated MMP block */
2215 	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
2216 
2217 	/*
2218 	 * mmp_check_interval is used to verify if the MMP block has been
2219 	 * updated on the block device. The value is updated based on the
2220 	 * maximum time to write the MMP block during an update cycle.
2221 	 */
2222 	__le16	mmp_check_interval;
2223 
2224 	__le16	mmp_pad1;
2225 	__le32	mmp_pad2[226];
2226 	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
2227 };
2228 
2229 /* arguments passed to the mmp thread */
2230 struct mmpd_data {
2231 	struct buffer_head *bh; /* bh from initial read_mmp_block() */
2232 	struct super_block *sb;  /* super block of the fs */
2233 };
2234 
2235 /*
2236  * Check interval multiplier
2237  * The MMP block is written every update interval and initially checked every
2238  * update interval x the multiplier (the value is then adapted based on the
2239  * write latency). The reason is that writes can be delayed under load and we
2240  * don't want readers to incorrectly assume that the filesystem is no longer
2241  * in use.
2242  */
2243 #define EXT4_MMP_CHECK_MULT		2UL
2244 
2245 /*
2246  * Minimum interval for MMP checking in seconds.
2247  */
2248 #define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
2249 
2250 /*
2251  * Maximum interval for MMP checking in seconds.
2252  */
2253 #define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
2254 
2255 /*
2256  * Function prototypes
2257  */
2258 
2259 /*
2260  * Ok, these declarations are also in <linux/kernel.h> but none of the
2261  * ext4 source programs needs to include it so they are duplicated here.
2262  */
2263 # define NORET_TYPE	/**/
2264 # define ATTRIB_NORET	__attribute__((noreturn))
2265 # define NORET_AND	noreturn,
2266 
2267 /* bitmap.c */
2268 extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
2269 void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2270 				struct ext4_group_desc *gdp,
2271 				struct buffer_head *bh, int sz);
2272 int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2273 				  struct ext4_group_desc *gdp,
2274 				  struct buffer_head *bh, int sz);
2275 void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
2276 				struct ext4_group_desc *gdp,
2277 				struct buffer_head *bh);
2278 int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
2279 				  struct ext4_group_desc *gdp,
2280 				  struct buffer_head *bh);
2281 
2282 /* balloc.c */
2283 extern void ext4_get_group_no_and_offset(struct super_block *sb,
2284 					 ext4_fsblk_t blocknr,
2285 					 ext4_group_t *blockgrpp,
2286 					 ext4_grpblk_t *offsetp);
2287 extern ext4_group_t ext4_get_group_number(struct super_block *sb,
2288 					  ext4_fsblk_t block);
2289 
2290 extern unsigned int ext4_block_group(struct super_block *sb,
2291 			ext4_fsblk_t blocknr);
2292 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
2293 			ext4_fsblk_t blocknr);
2294 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
2295 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
2296 			ext4_group_t group);
2297 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
2298 					 ext4_fsblk_t goal,
2299 					 unsigned int flags,
2300 					 unsigned long *count,
2301 					 int *errp);
2302 extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
2303 				    s64 nclusters, unsigned int flags);
2304 extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
2305 extern void ext4_check_blocks_bitmap(struct super_block *);
2306 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
2307 						    ext4_group_t block_group,
2308 						    struct buffer_head ** bh);
2309 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
2310 
2311 extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
2312 						ext4_group_t block_group);
2313 extern int ext4_wait_block_bitmap(struct super_block *sb,
2314 				  ext4_group_t block_group,
2315 				  struct buffer_head *bh);
2316 extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
2317 						  ext4_group_t block_group);
2318 extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
2319 					      ext4_group_t block_group,
2320 					      struct ext4_group_desc *gdp);
2321 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
2322 
ext4_encrypted_inode(struct inode * inode)2323 static inline bool ext4_encrypted_inode(struct inode *inode)
2324 {
2325 	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
2326 }
2327 
2328 #ifdef CONFIG_EXT4_FS_ENCRYPTION
ext4_fname_from_fscrypt_name(struct ext4_filename * dst,const struct fscrypt_name * src)2329 static inline void ext4_fname_from_fscrypt_name(struct ext4_filename *dst,
2330 						const struct fscrypt_name *src)
2331 {
2332 	memset(dst, 0, sizeof(*dst));
2333 
2334 	dst->usr_fname = src->usr_fname;
2335 	dst->disk_name = src->disk_name;
2336 	dst->hinfo.hash = src->hash;
2337 	dst->hinfo.minor_hash = src->minor_hash;
2338 	dst->crypto_buf = src->crypto_buf;
2339 }
2340 
ext4_fname_setup_filename(struct inode * dir,const struct qstr * iname,int lookup,struct ext4_filename * fname)2341 static inline int ext4_fname_setup_filename(struct inode *dir,
2342 					    const struct qstr *iname,
2343 					    int lookup,
2344 					    struct ext4_filename *fname)
2345 {
2346 	struct fscrypt_name name;
2347 	int err;
2348 
2349 	err = fscrypt_setup_filename(dir, iname, lookup, &name);
2350 	if (err)
2351 		return err;
2352 
2353 	ext4_fname_from_fscrypt_name(fname, &name);
2354 	return 0;
2355 }
2356 
ext4_fname_prepare_lookup(struct inode * dir,struct dentry * dentry,struct ext4_filename * fname)2357 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2358 					    struct dentry *dentry,
2359 					    struct ext4_filename *fname)
2360 {
2361 	struct fscrypt_name name;
2362 	int err;
2363 
2364 	err = fscrypt_prepare_lookup(dir, dentry, &name);
2365 	if (err)
2366 		return err;
2367 
2368 	ext4_fname_from_fscrypt_name(fname, &name);
2369 	return 0;
2370 }
2371 
ext4_fname_free_filename(struct ext4_filename * fname)2372 static inline void ext4_fname_free_filename(struct ext4_filename *fname)
2373 {
2374 	struct fscrypt_name name;
2375 
2376 	name.crypto_buf = fname->crypto_buf;
2377 	fscrypt_free_filename(&name);
2378 
2379 	fname->crypto_buf.name = NULL;
2380 	fname->usr_fname = NULL;
2381 	fname->disk_name.name = NULL;
2382 }
2383 #else /* !CONFIG_EXT4_FS_ENCRYPTION */
ext4_fname_setup_filename(struct inode * dir,const struct qstr * iname,int lookup,struct ext4_filename * fname)2384 static inline int ext4_fname_setup_filename(struct inode *dir,
2385 					    const struct qstr *iname,
2386 					    int lookup,
2387 					    struct ext4_filename *fname)
2388 {
2389 	fname->usr_fname = iname;
2390 	fname->disk_name.name = (unsigned char *) iname->name;
2391 	fname->disk_name.len = iname->len;
2392 	return 0;
2393 }
2394 
ext4_fname_prepare_lookup(struct inode * dir,struct dentry * dentry,struct ext4_filename * fname)2395 static inline int ext4_fname_prepare_lookup(struct inode *dir,
2396 					    struct dentry *dentry,
2397 					    struct ext4_filename *fname)
2398 {
2399 	return ext4_fname_setup_filename(dir, &dentry->d_name, 1, fname);
2400 }
2401 
ext4_fname_free_filename(struct ext4_filename * fname)2402 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
2403 #endif /* !CONFIG_EXT4_FS_ENCRYPTION */
2404 
2405 /* dir.c */
2406 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2407 				  struct file *,
2408 				  struct ext4_dir_entry_2 *,
2409 				  struct buffer_head *, char *, int,
2410 				  unsigned int);
2411 #define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2412 	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2413 					(de), (bh), (buf), (size), (offset)))
2414 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2415 				__u32 minor_hash,
2416 				struct ext4_dir_entry_2 *dirent,
2417 				struct fscrypt_str *ent_name);
2418 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2419 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2420 			     struct buffer_head *bh,
2421 			     void *buf, int buf_size,
2422 			     struct ext4_filename *fname,
2423 			     struct ext4_dir_entry_2 **dest_de);
2424 void ext4_insert_dentry(struct inode *inode,
2425 			struct ext4_dir_entry_2 *de,
2426 			int buf_size,
2427 			struct ext4_filename *fname);
ext4_update_dx_flag(struct inode * inode)2428 static inline void ext4_update_dx_flag(struct inode *inode)
2429 {
2430 	if (!ext4_has_feature_dir_index(inode->i_sb)) {
2431 		/* ext4_iget() should have caught this... */
2432 		WARN_ON_ONCE(ext4_has_feature_metadata_csum(inode->i_sb));
2433 		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2434 	}
2435 }
2436 static const unsigned char ext4_filetype_table[] = {
2437 	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2438 };
2439 
get_dtype(struct super_block * sb,int filetype)2440 static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2441 {
2442 	if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
2443 		return DT_UNKNOWN;
2444 
2445 	return ext4_filetype_table[filetype];
2446 }
2447 extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
2448 			     void *buf, int buf_size);
2449 
2450 /* fsync.c */
2451 extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
2452 
2453 /* hash.c */
2454 extern int ext4fs_dirhash(const char *name, int len, struct
2455 			  dx_hash_info *hinfo);
2456 
2457 /* ialloc.c */
2458 extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2459 				      const struct qstr *qstr, __u32 goal,
2460 				      uid_t *owner, __u32 i_flags,
2461 				      int handle_type, unsigned int line_no,
2462 				      int nblocks);
2463 
2464 #define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
2465 	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2466 			 i_flags, 0, 0, 0)
2467 #define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2468 				    type, nblocks)		    \
2469 	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2470 			 0, (type), __LINE__, (nblocks))
2471 
2472 
2473 extern void ext4_free_inode(handle_t *, struct inode *);
2474 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2475 extern unsigned long ext4_count_free_inodes(struct super_block *);
2476 extern unsigned long ext4_count_dirs(struct super_block *);
2477 extern void ext4_check_inodes_bitmap(struct super_block *);
2478 extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2479 extern int ext4_init_inode_table(struct super_block *sb,
2480 				 ext4_group_t group, int barrier);
2481 extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2482 
2483 /* mballoc.c */
2484 extern const struct seq_operations ext4_mb_seq_groups_ops;
2485 extern long ext4_mb_stats;
2486 extern long ext4_mb_max_to_scan;
2487 extern int ext4_mb_init(struct super_block *);
2488 extern int ext4_mb_release(struct super_block *);
2489 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2490 				struct ext4_allocation_request *, int *);
2491 extern int ext4_mb_reserve_blocks(struct super_block *, int);
2492 extern void ext4_discard_preallocations(struct inode *);
2493 extern int __init ext4_init_mballoc(void);
2494 extern void ext4_exit_mballoc(void);
2495 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2496 			     struct buffer_head *bh, ext4_fsblk_t block,
2497 			     unsigned long count, int flags);
2498 extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2499 				   ext4_group_t ngroups);
2500 extern int ext4_mb_add_groupinfo(struct super_block *sb,
2501 		ext4_group_t i, struct ext4_group_desc *desc);
2502 extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2503 				ext4_fsblk_t block, unsigned long count);
2504 extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2505 extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid);
2506 
2507 /* inode.c */
2508 int ext4_inode_is_fast_symlink(struct inode *inode);
2509 struct buffer_head *ext4_getblk(handle_t *, struct inode *, ext4_lblk_t, int);
2510 struct buffer_head *ext4_bread(handle_t *, struct inode *, ext4_lblk_t, int);
2511 int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
2512 		     bool wait, struct buffer_head **bhs);
2513 int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
2514 			     struct buffer_head *bh_result, int create);
2515 int ext4_get_block(struct inode *inode, sector_t iblock,
2516 		   struct buffer_head *bh_result, int create);
2517 int ext4_dio_get_block(struct inode *inode, sector_t iblock,
2518 		       struct buffer_head *bh_result, int create);
2519 int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2520 			   struct buffer_head *bh, int create);
2521 int ext4_walk_page_buffers(handle_t *handle,
2522 			   struct buffer_head *head,
2523 			   unsigned from,
2524 			   unsigned to,
2525 			   int *partial,
2526 			   int (*fn)(handle_t *handle,
2527 				     struct buffer_head *bh));
2528 int do_journal_get_write_access(handle_t *handle,
2529 				struct buffer_head *bh);
2530 #define FALL_BACK_TO_NONDELALLOC 1
2531 #define CONVERT_INLINE_DATA	 2
2532 
2533 typedef enum {
2534 	EXT4_IGET_NORMAL =	0,
2535 	EXT4_IGET_SPECIAL =	0x0001, /* OK to iget a system inode */
2536 	EXT4_IGET_HANDLE = 	0x0002	/* Inode # is from a handle */
2537 } ext4_iget_flags;
2538 
2539 extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
2540 				 ext4_iget_flags flags, const char *function,
2541 				 unsigned int line);
2542 
2543 #define ext4_iget(sb, ino, flags) \
2544 	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
2545 
2546 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2547 extern int  ext4_setattr(struct dentry *, struct iattr *);
2548 extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
2549 extern void ext4_evict_inode(struct inode *);
2550 extern void ext4_clear_inode(struct inode *);
2551 extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
2552 extern int  ext4_sync_inode(handle_t *, struct inode *);
2553 extern void ext4_dirty_inode(struct inode *, int);
2554 extern int ext4_change_inode_journal_flag(struct inode *, int);
2555 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2556 extern int ext4_inode_attach_jinode(struct inode *inode);
2557 extern int ext4_can_truncate(struct inode *inode);
2558 extern int ext4_truncate(struct inode *);
2559 extern int ext4_break_layouts(struct inode *);
2560 extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2561 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2562 extern void ext4_set_inode_flags(struct inode *);
2563 extern int ext4_alloc_da_blocks(struct inode *inode);
2564 extern void ext4_set_aops(struct inode *inode);
2565 extern int ext4_writepage_trans_blocks(struct inode *);
2566 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2567 extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2568 			     loff_t lstart, loff_t lend);
2569 extern int ext4_page_mkwrite(struct vm_fault *vmf);
2570 extern int ext4_filemap_fault(struct vm_fault *vmf);
2571 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2572 extern int ext4_get_projid(struct inode *inode, kprojid_t *projid);
2573 extern void ext4_da_update_reserve_space(struct inode *inode,
2574 					int used, int quota_claim);
2575 extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
2576 			      ext4_fsblk_t pblk, ext4_lblk_t len);
2577 
2578 /* indirect.c */
2579 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2580 				struct ext4_map_blocks *map, int flags);
2581 extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2582 extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2583 extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2584 extern int ext4_ind_remove_space(handle_t *handle, struct inode *inode,
2585 				 ext4_lblk_t start, ext4_lblk_t end);
2586 
2587 /* ioctl.c */
2588 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2589 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2590 
2591 /* migrate.c */
2592 extern int ext4_ext_migrate(struct inode *);
2593 extern int ext4_ind_migrate(struct inode *inode);
2594 
2595 /* namei.c */
2596 extern int ext4_dirent_csum_verify(struct inode *inode,
2597 				   struct ext4_dir_entry *dirent);
2598 extern int ext4_orphan_add(handle_t *, struct inode *);
2599 extern int ext4_orphan_del(handle_t *, struct inode *);
2600 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2601 				__u32 start_minor_hash, __u32 *next_hash);
2602 extern int ext4_search_dir(struct buffer_head *bh,
2603 			   char *search_buf,
2604 			   int buf_size,
2605 			   struct inode *dir,
2606 			   struct ext4_filename *fname,
2607 			   unsigned int offset,
2608 			   struct ext4_dir_entry_2 **res_dir);
2609 extern int ext4_generic_delete_entry(handle_t *handle,
2610 				     struct inode *dir,
2611 				     struct ext4_dir_entry_2 *de_del,
2612 				     struct buffer_head *bh,
2613 				     void *entry_buf,
2614 				     int buf_size,
2615 				     int csum_size);
2616 extern bool ext4_empty_dir(struct inode *inode);
2617 
2618 /* resize.c */
2619 extern void ext4_kvfree_array_rcu(void *to_free);
2620 extern int ext4_group_add(struct super_block *sb,
2621 				struct ext4_new_group_data *input);
2622 extern int ext4_group_extend(struct super_block *sb,
2623 				struct ext4_super_block *es,
2624 				ext4_fsblk_t n_blocks_count);
2625 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2626 
2627 /* super.c */
2628 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
2629 					 sector_t block, int op_flags);
2630 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
2631 extern int ext4_calculate_overhead(struct super_block *sb);
2632 extern void ext4_superblock_csum_set(struct super_block *sb);
2633 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2634 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2635 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2636 				    ext4_group_t ngroup);
2637 extern const char *ext4_decode_error(struct super_block *sb, int errno,
2638 				     char nbuf[16]);
2639 extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
2640 					     ext4_group_t block_group,
2641 					     unsigned int flags);
2642 
2643 extern __printf(4, 5)
2644 void __ext4_error(struct super_block *, const char *, unsigned int,
2645 		  const char *, ...);
2646 extern __printf(5, 6)
2647 void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2648 		      const char *, ...);
2649 extern __printf(5, 6)
2650 void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2651 		     const char *, ...);
2652 extern void __ext4_std_error(struct super_block *, const char *,
2653 			     unsigned int, int);
2654 extern __printf(4, 5)
2655 void __ext4_abort(struct super_block *, const char *, unsigned int,
2656 		  const char *, ...);
2657 extern __printf(4, 5)
2658 void __ext4_warning(struct super_block *, const char *, unsigned int,
2659 		    const char *, ...);
2660 extern __printf(4, 5)
2661 void __ext4_warning_inode(const struct inode *inode, const char *function,
2662 			  unsigned int line, const char *fmt, ...);
2663 extern __printf(3, 4)
2664 void __ext4_msg(struct super_block *, const char *, const char *, ...);
2665 extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2666 			   const char *, unsigned int, const char *);
2667 extern __printf(7, 8)
2668 void __ext4_grp_locked_error(const char *, unsigned int,
2669 			     struct super_block *, ext4_group_t,
2670 			     unsigned long, ext4_fsblk_t,
2671 			     const char *, ...);
2672 
2673 #define EXT4_ERROR_INODE(inode, fmt, a...) \
2674 	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
2675 
2676 #define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
2677 	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
2678 
2679 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
2680 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
2681 
2682 #ifdef CONFIG_PRINTK
2683 
2684 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2685 	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2686 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2687 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2688 #define ext4_error(sb, fmt, ...)					\
2689 	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2690 #define ext4_abort(sb, fmt, ...)					\
2691 	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2692 #define ext4_warning(sb, fmt, ...)					\
2693 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2694 #define ext4_warning_inode(inode, fmt, ...)				\
2695 	__ext4_warning_inode(inode, __func__, __LINE__, fmt, ##__VA_ARGS__)
2696 #define ext4_msg(sb, level, fmt, ...)				\
2697 	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2698 #define dump_mmp_msg(sb, mmp, msg)					\
2699 	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2700 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2701 	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2702 				fmt, ##__VA_ARGS__)
2703 
2704 #else
2705 
2706 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2707 do {									\
2708 	no_printk(fmt, ##__VA_ARGS__);					\
2709 	__ext4_error_inode(inode, "", 0, block, " ");			\
2710 } while (0)
2711 #define ext4_error_file(file, func, line, block, fmt, ...)		\
2712 do {									\
2713 	no_printk(fmt, ##__VA_ARGS__);					\
2714 	__ext4_error_file(file, "", 0, block, " ");			\
2715 } while (0)
2716 #define ext4_error(sb, fmt, ...)					\
2717 do {									\
2718 	no_printk(fmt, ##__VA_ARGS__);					\
2719 	__ext4_error(sb, "", 0, " ");					\
2720 } while (0)
2721 #define ext4_abort(sb, fmt, ...)					\
2722 do {									\
2723 	no_printk(fmt, ##__VA_ARGS__);					\
2724 	__ext4_abort(sb, "", 0, " ");					\
2725 } while (0)
2726 #define ext4_warning(sb, fmt, ...)					\
2727 do {									\
2728 	no_printk(fmt, ##__VA_ARGS__);					\
2729 	__ext4_warning(sb, "", 0, " ");					\
2730 } while (0)
2731 #define ext4_warning_inode(inode, fmt, ...)				\
2732 do {									\
2733 	no_printk(fmt, ##__VA_ARGS__);					\
2734 	__ext4_warning_inode(inode, "", 0, " ");			\
2735 } while (0)
2736 #define ext4_msg(sb, level, fmt, ...)					\
2737 do {									\
2738 	no_printk(fmt, ##__VA_ARGS__);					\
2739 	__ext4_msg(sb, "", " ");					\
2740 } while (0)
2741 #define dump_mmp_msg(sb, mmp, msg)					\
2742 	__dump_mmp_msg(sb, mmp, "", 0, "")
2743 #define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2744 do {									\
2745 	no_printk(fmt, ##__VA_ARGS__);				\
2746 	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2747 } while (0)
2748 
2749 #endif
2750 
2751 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2752 					__u32 compat);
2753 extern int ext4_update_rocompat_feature(handle_t *handle,
2754 					struct super_block *sb,	__u32 rocompat);
2755 extern int ext4_update_incompat_feature(handle_t *handle,
2756 					struct super_block *sb,	__u32 incompat);
2757 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2758 				      struct ext4_group_desc *bg);
2759 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2760 				      struct ext4_group_desc *bg);
2761 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2762 				     struct ext4_group_desc *bg);
2763 extern __u32 ext4_free_group_clusters(struct super_block *sb,
2764 				      struct ext4_group_desc *bg);
2765 extern __u32 ext4_free_inodes_count(struct super_block *sb,
2766 				 struct ext4_group_desc *bg);
2767 extern __u32 ext4_used_dirs_count(struct super_block *sb,
2768 				struct ext4_group_desc *bg);
2769 extern __u32 ext4_itable_unused_count(struct super_block *sb,
2770 				   struct ext4_group_desc *bg);
2771 extern void ext4_block_bitmap_set(struct super_block *sb,
2772 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2773 extern void ext4_inode_bitmap_set(struct super_block *sb,
2774 				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2775 extern void ext4_inode_table_set(struct super_block *sb,
2776 				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2777 extern void ext4_free_group_clusters_set(struct super_block *sb,
2778 					 struct ext4_group_desc *bg,
2779 					 __u32 count);
2780 extern void ext4_free_inodes_set(struct super_block *sb,
2781 				struct ext4_group_desc *bg, __u32 count);
2782 extern void ext4_used_dirs_set(struct super_block *sb,
2783 				struct ext4_group_desc *bg, __u32 count);
2784 extern void ext4_itable_unused_set(struct super_block *sb,
2785 				   struct ext4_group_desc *bg, __u32 count);
2786 extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2787 				       struct ext4_group_desc *gdp);
2788 extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2789 				     struct ext4_group_desc *gdp);
2790 extern int ext4_register_li_request(struct super_block *sb,
2791 				    ext4_group_t first_not_zeroed);
2792 
ext4_has_metadata_csum(struct super_block * sb)2793 static inline int ext4_has_metadata_csum(struct super_block *sb)
2794 {
2795 	WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) &&
2796 		     !EXT4_SB(sb)->s_chksum_driver);
2797 
2798 	return ext4_has_feature_metadata_csum(sb) &&
2799 	       (EXT4_SB(sb)->s_chksum_driver != NULL);
2800 }
2801 
ext4_has_group_desc_csum(struct super_block * sb)2802 static inline int ext4_has_group_desc_csum(struct super_block *sb)
2803 {
2804 	return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb);
2805 }
2806 
ext4_blocks_count(struct ext4_super_block * es)2807 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2808 {
2809 	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2810 		le32_to_cpu(es->s_blocks_count_lo);
2811 }
2812 
ext4_r_blocks_count(struct ext4_super_block * es)2813 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2814 {
2815 	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2816 		le32_to_cpu(es->s_r_blocks_count_lo);
2817 }
2818 
ext4_free_blocks_count(struct ext4_super_block * es)2819 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2820 {
2821 	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2822 		le32_to_cpu(es->s_free_blocks_count_lo);
2823 }
2824 
ext4_blocks_count_set(struct ext4_super_block * es,ext4_fsblk_t blk)2825 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2826 					 ext4_fsblk_t blk)
2827 {
2828 	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2829 	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2830 }
2831 
ext4_free_blocks_count_set(struct ext4_super_block * es,ext4_fsblk_t blk)2832 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2833 					      ext4_fsblk_t blk)
2834 {
2835 	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2836 	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2837 }
2838 
ext4_r_blocks_count_set(struct ext4_super_block * es,ext4_fsblk_t blk)2839 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2840 					   ext4_fsblk_t blk)
2841 {
2842 	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2843 	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2844 }
2845 
ext4_isize(struct super_block * sb,struct ext4_inode * raw_inode)2846 static inline loff_t ext4_isize(struct super_block *sb,
2847 				struct ext4_inode *raw_inode)
2848 {
2849 	if (ext4_has_feature_largedir(sb) ||
2850 	    S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2851 		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2852 			le32_to_cpu(raw_inode->i_size_lo);
2853 
2854 	return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2855 }
2856 
ext4_isize_set(struct ext4_inode * raw_inode,loff_t i_size)2857 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2858 {
2859 	raw_inode->i_size_lo = cpu_to_le32(i_size);
2860 	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2861 }
2862 
2863 static inline
ext4_get_group_info(struct super_block * sb,ext4_group_t group)2864 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2865 					    ext4_group_t group)
2866 {
2867 	 struct ext4_group_info **grp_info;
2868 	 long indexv, indexh;
2869 	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2870 	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2871 	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2872 	 grp_info = sbi_array_rcu_deref(EXT4_SB(sb), s_group_info, indexv);
2873 	 return grp_info[indexh];
2874 }
2875 
2876 /*
2877  * Reading s_groups_count requires using smp_rmb() afterwards.  See
2878  * the locking protocol documented in the comments of ext4_group_add()
2879  * in resize.c
2880  */
ext4_get_groups_count(struct super_block * sb)2881 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2882 {
2883 	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2884 
2885 	smp_rmb();
2886 	return ngroups;
2887 }
2888 
ext4_flex_group(struct ext4_sb_info * sbi,ext4_group_t block_group)2889 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2890 					     ext4_group_t block_group)
2891 {
2892 	return block_group >> sbi->s_log_groups_per_flex;
2893 }
2894 
ext4_flex_bg_size(struct ext4_sb_info * sbi)2895 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2896 {
2897 	return 1 << sbi->s_log_groups_per_flex;
2898 }
2899 
2900 #define ext4_std_error(sb, errno)				\
2901 do {								\
2902 	if ((errno))						\
2903 		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2904 } while (0)
2905 
2906 #ifdef CONFIG_SMP
2907 /* Each CPU can accumulate percpu_counter_batch clusters in their local
2908  * counters. So we need to make sure we have free clusters more
2909  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2910  */
2911 #define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2912 #else
2913 #define EXT4_FREECLUSTERS_WATERMARK 0
2914 #endif
2915 
2916 /* Update i_disksize. Requires i_mutex to avoid races with truncate */
ext4_update_i_disksize(struct inode * inode,loff_t newsize)2917 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2918 {
2919 	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2920 		     !inode_is_locked(inode));
2921 	down_write(&EXT4_I(inode)->i_data_sem);
2922 	if (newsize > EXT4_I(inode)->i_disksize)
2923 		WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize);
2924 	up_write(&EXT4_I(inode)->i_data_sem);
2925 }
2926 
2927 /* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
ext4_update_inode_size(struct inode * inode,loff_t newsize)2928 static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
2929 {
2930 	int changed = 0;
2931 
2932 	if (newsize > inode->i_size) {
2933 		i_size_write(inode, newsize);
2934 		changed = 1;
2935 	}
2936 	if (newsize > EXT4_I(inode)->i_disksize) {
2937 		ext4_update_i_disksize(inode, newsize);
2938 		changed |= 2;
2939 	}
2940 	return changed;
2941 }
2942 
2943 int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
2944 				      loff_t len);
2945 
2946 struct ext4_group_info {
2947 	unsigned long   bb_state;
2948 	struct rb_root  bb_free_root;
2949 	ext4_grpblk_t	bb_first_free;	/* first free block */
2950 	ext4_grpblk_t	bb_free;	/* total free blocks */
2951 	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2952 	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2953 	struct          list_head bb_prealloc_list;
2954 #ifdef DOUBLE_CHECK
2955 	void            *bb_bitmap;
2956 #endif
2957 	struct rw_semaphore alloc_sem;
2958 	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2959 					 * regions, index is order.
2960 					 * bb_counters[3] = 5 means
2961 					 * 5 free 8-block regions. */
2962 };
2963 
2964 #define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2965 #define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2966 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2967 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2968 #define EXT4_GROUP_INFO_BBITMAP_CORRUPT		\
2969 	(1 << EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT)
2970 #define EXT4_GROUP_INFO_IBITMAP_CORRUPT		\
2971 	(1 << EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT)
2972 
2973 #define EXT4_MB_GRP_NEED_INIT(grp)	\
2974 	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2975 #define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2976 	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2977 #define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2978 	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2979 
2980 #define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2981 	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2982 #define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2983 	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2984 #define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2985 	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2986 
2987 #define EXT4_MAX_CONTENTION		8
2988 #define EXT4_CONTENTION_THRESHOLD	2
2989 
ext4_group_lock_ptr(struct super_block * sb,ext4_group_t group)2990 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2991 					      ext4_group_t group)
2992 {
2993 	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2994 }
2995 
2996 /*
2997  * Returns true if the filesystem is busy enough that attempts to
2998  * access the block group locks has run into contention.
2999  */
ext4_fs_is_busy(struct ext4_sb_info * sbi)3000 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
3001 {
3002 	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
3003 }
3004 
ext4_lock_group(struct super_block * sb,ext4_group_t group)3005 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
3006 {
3007 	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
3008 	if (spin_trylock(lock))
3009 		/*
3010 		 * We're able to grab the lock right away, so drop the
3011 		 * lock contention counter.
3012 		 */
3013 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
3014 	else {
3015 		/*
3016 		 * The lock is busy, so bump the contention counter,
3017 		 * and then wait on the spin lock.
3018 		 */
3019 		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
3020 				  EXT4_MAX_CONTENTION);
3021 		spin_lock(lock);
3022 	}
3023 }
3024 
ext4_unlock_group(struct super_block * sb,ext4_group_t group)3025 static inline void ext4_unlock_group(struct super_block *sb,
3026 					ext4_group_t group)
3027 {
3028 	spin_unlock(ext4_group_lock_ptr(sb, group));
3029 }
3030 
3031 /*
3032  * Block validity checking
3033  */
3034 #define ext4_check_indirect_blockref(inode, bh)				\
3035 	ext4_check_blockref(__func__, __LINE__, inode,			\
3036 			    (__le32 *)(bh)->b_data,			\
3037 			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
3038 
3039 #define ext4_ind_check_inode(inode)					\
3040 	ext4_check_blockref(__func__, __LINE__, inode,			\
3041 			    EXT4_I(inode)->i_data,			\
3042 			    EXT4_NDIR_BLOCKS)
3043 
3044 /*
3045  * Inodes and files operations
3046  */
3047 
3048 /* dir.c */
3049 extern const struct file_operations ext4_dir_operations;
3050 
3051 /* file.c */
3052 extern const struct inode_operations ext4_file_inode_operations;
3053 extern const struct file_operations ext4_file_operations;
3054 extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
3055 
3056 /* inline.c */
3057 extern int ext4_get_max_inline_size(struct inode *inode);
3058 extern int ext4_find_inline_data_nolock(struct inode *inode);
3059 extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
3060 				 unsigned int len);
3061 extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
3062 
3063 extern int ext4_readpage_inline(struct inode *inode, struct page *page);
3064 extern int ext4_try_to_write_inline_data(struct address_space *mapping,
3065 					 struct inode *inode,
3066 					 loff_t pos, unsigned len,
3067 					 unsigned flags,
3068 					 struct page **pagep);
3069 extern int ext4_write_inline_data_end(struct inode *inode,
3070 				      loff_t pos, unsigned len,
3071 				      unsigned copied,
3072 				      struct page *page);
3073 extern struct buffer_head *
3074 ext4_journalled_write_inline_data(struct inode *inode,
3075 				  unsigned len,
3076 				  struct page *page);
3077 extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
3078 					   struct inode *inode,
3079 					   loff_t pos, unsigned len,
3080 					   unsigned flags,
3081 					   struct page **pagep,
3082 					   void **fsdata);
3083 extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
3084 					 unsigned len, unsigned copied,
3085 					 struct page *page);
3086 extern int ext4_try_add_inline_entry(handle_t *handle,
3087 				     struct ext4_filename *fname,
3088 				     struct inode *dir, struct inode *inode);
3089 extern int ext4_try_create_inline_dir(handle_t *handle,
3090 				      struct inode *parent,
3091 				      struct inode *inode);
3092 extern int ext4_read_inline_dir(struct file *filp,
3093 				struct dir_context *ctx,
3094 				int *has_inline_data);
3095 extern int htree_inlinedir_to_tree(struct file *dir_file,
3096 				   struct inode *dir, ext4_lblk_t block,
3097 				   struct dx_hash_info *hinfo,
3098 				   __u32 start_hash, __u32 start_minor_hash,
3099 				   int *has_inline_data);
3100 extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
3101 					struct ext4_filename *fname,
3102 					struct ext4_dir_entry_2 **res_dir,
3103 					int *has_inline_data);
3104 extern int ext4_delete_inline_entry(handle_t *handle,
3105 				    struct inode *dir,
3106 				    struct ext4_dir_entry_2 *de_del,
3107 				    struct buffer_head *bh,
3108 				    int *has_inline_data);
3109 extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
3110 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
3111 					struct ext4_dir_entry_2 **parent_de,
3112 					int *retval);
3113 extern int ext4_inline_data_fiemap(struct inode *inode,
3114 				   struct fiemap_extent_info *fieinfo,
3115 				   int *has_inline, __u64 start, __u64 len);
3116 
3117 struct iomap;
3118 extern int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap);
3119 
3120 extern int ext4_inline_data_truncate(struct inode *inode, int *has_inline);
3121 
3122 extern int ext4_convert_inline_data(struct inode *inode);
3123 
ext4_has_inline_data(struct inode * inode)3124 static inline int ext4_has_inline_data(struct inode *inode)
3125 {
3126 	return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
3127 	       EXT4_I(inode)->i_inline_off;
3128 }
3129 
3130 /* namei.c */
3131 extern const struct inode_operations ext4_dir_inode_operations;
3132 extern const struct inode_operations ext4_special_inode_operations;
3133 extern struct dentry *ext4_get_parent(struct dentry *child);
3134 extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
3135 				 struct ext4_dir_entry_2 *de,
3136 				 int blocksize, int csum_size,
3137 				 unsigned int parent_ino, int dotdot_real_len);
3138 extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
3139 				   unsigned int blocksize);
3140 extern int ext4_handle_dirty_dirent_node(handle_t *handle,
3141 					 struct inode *inode,
3142 					 struct buffer_head *bh);
3143 #define S_SHIFT 12
3144 static const unsigned char ext4_type_by_mode[(S_IFMT >> S_SHIFT) + 1] = {
3145 	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
3146 	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
3147 	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
3148 	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
3149 	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
3150 	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
3151 	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
3152 };
3153 
ext4_set_de_type(struct super_block * sb,struct ext4_dir_entry_2 * de,umode_t mode)3154 static inline void ext4_set_de_type(struct super_block *sb,
3155 				struct ext4_dir_entry_2 *de,
3156 				umode_t mode) {
3157 	if (ext4_has_feature_filetype(sb))
3158 		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
3159 }
3160 
3161 /* readpages.c */
3162 extern int ext4_mpage_readpages(struct address_space *mapping,
3163 				struct list_head *pages, struct page *page,
3164 				unsigned nr_pages, bool is_readahead);
3165 
3166 /* symlink.c */
3167 extern const struct inode_operations ext4_encrypted_symlink_inode_operations;
3168 extern const struct inode_operations ext4_symlink_inode_operations;
3169 extern const struct inode_operations ext4_fast_symlink_inode_operations;
3170 
3171 /* sysfs.c */
3172 extern int ext4_register_sysfs(struct super_block *sb);
3173 extern void ext4_unregister_sysfs(struct super_block *sb);
3174 extern int __init ext4_init_sysfs(void);
3175 extern void ext4_exit_sysfs(void);
3176 
3177 /* block_validity */
3178 extern void ext4_release_system_zone(struct super_block *sb);
3179 extern int ext4_setup_system_zone(struct super_block *sb);
3180 extern int __init ext4_init_system_zone(void);
3181 extern void ext4_exit_system_zone(void);
3182 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
3183 				 ext4_fsblk_t start_blk,
3184 				 unsigned int count);
3185 extern int ext4_check_blockref(const char *, unsigned int,
3186 			       struct inode *, __le32 *, unsigned int);
3187 
3188 /* extents.c */
3189 struct ext4_ext_path;
3190 struct ext4_extent;
3191 
3192 /*
3193  * Maximum number of logical blocks in a file; ext4_extent's ee_block is
3194  * __le32.
3195  */
3196 #define EXT_MAX_BLOCKS	0xffffffff
3197 
3198 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
3199 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
3200 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
3201 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3202 			       struct ext4_map_blocks *map, int flags);
3203 extern int ext4_ext_truncate(handle_t *, struct inode *);
3204 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
3205 				 ext4_lblk_t end);
3206 extern void ext4_ext_init(struct super_block *);
3207 extern void ext4_ext_release(struct super_block *);
3208 extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
3209 			  loff_t len);
3210 extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
3211 					  loff_t offset, ssize_t len);
3212 extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
3213 			   struct ext4_map_blocks *map, int flags);
3214 extern int ext4_ext_calc_metadata_amount(struct inode *inode,
3215 					 ext4_lblk_t lblocks);
3216 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
3217 						   int num,
3218 						   struct ext4_ext_path *path);
3219 extern int ext4_can_extents_be_merged(struct inode *inode,
3220 				      struct ext4_extent *ex1,
3221 				      struct ext4_extent *ex2);
3222 extern int ext4_ext_insert_extent(handle_t *, struct inode *,
3223 				  struct ext4_ext_path **,
3224 				  struct ext4_extent *, int);
3225 extern struct ext4_ext_path *ext4_find_extent(struct inode *, ext4_lblk_t,
3226 					      struct ext4_ext_path **,
3227 					      int flags);
3228 extern void ext4_ext_drop_refs(struct ext4_ext_path *);
3229 extern int ext4_ext_check_inode(struct inode *inode);
3230 extern int ext4_find_delalloc_range(struct inode *inode,
3231 				    ext4_lblk_t lblk_start,
3232 				    ext4_lblk_t lblk_end);
3233 extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
3234 extern ext4_lblk_t ext4_ext_next_allocated_block(struct ext4_ext_path *path);
3235 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
3236 			__u64 start, __u64 len);
3237 extern int ext4_ext_precache(struct inode *inode);
3238 extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
3239 extern int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len);
3240 extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
3241 				struct inode *inode2, ext4_lblk_t lblk1,
3242 			     ext4_lblk_t lblk2,  ext4_lblk_t count,
3243 			     int mark_unwritten,int *err);
3244 
3245 /* move_extent.c */
3246 extern void ext4_double_down_write_data_sem(struct inode *first,
3247 					    struct inode *second);
3248 extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
3249 					  struct inode *donor_inode);
3250 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
3251 			     __u64 start_orig, __u64 start_donor,
3252 			     __u64 len, __u64 *moved_len);
3253 
3254 /* page-io.c */
3255 extern int __init ext4_init_pageio(void);
3256 extern void ext4_exit_pageio(void);
3257 extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
3258 extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
3259 extern int ext4_put_io_end(ext4_io_end_t *io_end);
3260 extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
3261 extern void ext4_io_submit_init(struct ext4_io_submit *io,
3262 				struct writeback_control *wbc);
3263 extern void ext4_end_io_rsv_work(struct work_struct *work);
3264 extern void ext4_io_submit(struct ext4_io_submit *io);
3265 extern int ext4_bio_write_page(struct ext4_io_submit *io,
3266 			       struct page *page,
3267 			       int len,
3268 			       struct writeback_control *wbc,
3269 			       bool keep_towrite);
3270 
3271 /* mmp.c */
3272 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
3273 
3274 /*
3275  * Add new method to test whether block and inode bitmaps are properly
3276  * initialized. With uninit_bg reading the block from disk is not enough
3277  * to mark the bitmap uptodate. We need to also zero-out the bitmap
3278  */
3279 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
3280 
bitmap_uptodate(struct buffer_head * bh)3281 static inline int bitmap_uptodate(struct buffer_head *bh)
3282 {
3283 	return (buffer_uptodate(bh) &&
3284 			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
3285 }
set_bitmap_uptodate(struct buffer_head * bh)3286 static inline void set_bitmap_uptodate(struct buffer_head *bh)
3287 {
3288 	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
3289 }
3290 
3291 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
3292 
3293 /* For ioend & aio unwritten conversion wait queues */
3294 #define EXT4_WQ_HASH_SZ		37
3295 #define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
3296 					    EXT4_WQ_HASH_SZ])
3297 extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
3298 
3299 extern int ext4_resize_begin(struct super_block *sb);
3300 extern void ext4_resize_end(struct super_block *sb);
3301 
ext4_set_io_unwritten_flag(struct inode * inode,struct ext4_io_end * io_end)3302 static inline void ext4_set_io_unwritten_flag(struct inode *inode,
3303 					      struct ext4_io_end *io_end)
3304 {
3305 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
3306 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
3307 		atomic_inc(&EXT4_I(inode)->i_unwritten);
3308 	}
3309 }
3310 
ext4_clear_io_unwritten_flag(ext4_io_end_t * io_end)3311 static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
3312 {
3313 	struct inode *inode = io_end->inode;
3314 
3315 	if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
3316 		io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
3317 		/* Wake up anyone waiting on unwritten extent conversion */
3318 		if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
3319 			wake_up_all(ext4_ioend_wq(inode));
3320 	}
3321 }
3322 
3323 extern const struct iomap_ops ext4_iomap_ops;
3324 
3325 #endif	/* __KERNEL__ */
3326 
3327 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
3328 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
3329 
3330 #endif	/* _EXT4_H */
3331