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v3.5.6
   1/*
   2 *  ext4.h
   3 *
   4 * Copyright (C) 1992, 1993, 1994, 1995
   5 * Remy Card (card@masi.ibp.fr)
   6 * Laboratoire MASI - Institut Blaise Pascal
   7 * Universite Pierre et Marie Curie (Paris VI)
   8 *
   9 *  from
  10 *
  11 *  linux/include/linux/minix_fs.h
  12 *
  13 *  Copyright (C) 1991, 1992  Linus Torvalds
  14 */
  15
  16#ifndef _EXT4_H
  17#define _EXT4_H
  18
  19#include <linux/types.h>
  20#include <linux/blkdev.h>
  21#include <linux/magic.h>
  22#include <linux/jbd2.h>
  23#include <linux/quota.h>
  24#include <linux/rwsem.h>
  25#include <linux/rbtree.h>
  26#include <linux/seqlock.h>
  27#include <linux/mutex.h>
  28#include <linux/timer.h>
  29#include <linux/wait.h>
  30#include <linux/blockgroup_lock.h>
  31#include <linux/percpu_counter.h>
 
  32#include <crypto/hash.h>
 
  33#ifdef __KERNEL__
  34#include <linux/compat.h>
  35#endif
  36
  37/*
  38 * The fourth extended filesystem constants/structures
  39 */
  40
  41/*
  42 * Define EXT4FS_DEBUG to produce debug messages
  43 */
  44#undef EXT4FS_DEBUG
  45
  46/*
  47 * Debug code
  48 */
  49#ifdef EXT4FS_DEBUG
  50#define ext4_debug(f, a...)						\
  51	do {								\
  52		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
  53			__FILE__, __LINE__, __func__);			\
  54		printk(KERN_DEBUG f, ## a);				\
  55	} while (0)
  56#else
  57#define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
  58#endif
  59
 
 
 
 
 
 
 
 
 
 
  60#define EXT4_ERROR_INODE(inode, fmt, a...) \
  61	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
  62
  63#define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
  64	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
  65
  66#define EXT4_ERROR_FILE(file, block, fmt, a...)				\
  67	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
  68
  69/* data type for block offset of block group */
  70typedef int ext4_grpblk_t;
  71
  72/* data type for filesystem-wide blocks number */
  73typedef unsigned long long ext4_fsblk_t;
  74
  75/* data type for file logical block number */
  76typedef __u32 ext4_lblk_t;
  77
  78/* data type for block group number */
  79typedef unsigned int ext4_group_t;
  80
  81/*
  82 * Flags used in mballoc's allocation_context flags field.
  83 *
  84 * Also used to show what's going on for debugging purposes when the
  85 * flag field is exported via the traceport interface
  86 */
  87
  88/* prefer goal again. length */
  89#define EXT4_MB_HINT_MERGE		0x0001
  90/* blocks already reserved */
  91#define EXT4_MB_HINT_RESERVED		0x0002
  92/* metadata is being allocated */
  93#define EXT4_MB_HINT_METADATA		0x0004
  94/* first blocks in the file */
  95#define EXT4_MB_HINT_FIRST		0x0008
  96/* search for the best chunk */
  97#define EXT4_MB_HINT_BEST		0x0010
  98/* data is being allocated */
  99#define EXT4_MB_HINT_DATA		0x0020
 100/* don't preallocate (for tails) */
 101#define EXT4_MB_HINT_NOPREALLOC		0x0040
 102/* allocate for locality group */
 103#define EXT4_MB_HINT_GROUP_ALLOC	0x0080
 104/* allocate goal blocks or none */
 105#define EXT4_MB_HINT_GOAL_ONLY		0x0100
 106/* goal is meaningful */
 107#define EXT4_MB_HINT_TRY_GOAL		0x0200
 108/* blocks already pre-reserved by delayed allocation */
 109#define EXT4_MB_DELALLOC_RESERVED	0x0400
 110/* We are doing stream allocation */
 111#define EXT4_MB_STREAM_ALLOC		0x0800
 112/* Use reserved root blocks if needed */
 113#define EXT4_MB_USE_ROOT_BLOCKS		0x1000
 
 
 114
 115struct ext4_allocation_request {
 116	/* target inode for block we're allocating */
 117	struct inode *inode;
 118	/* how many blocks we want to allocate */
 119	unsigned int len;
 120	/* logical block in target inode */
 121	ext4_lblk_t logical;
 122	/* the closest logical allocated block to the left */
 123	ext4_lblk_t lleft;
 124	/* the closest logical allocated block to the right */
 125	ext4_lblk_t lright;
 126	/* phys. target (a hint) */
 127	ext4_fsblk_t goal;
 128	/* phys. block for the closest logical allocated block to the left */
 129	ext4_fsblk_t pleft;
 130	/* phys. block for the closest logical allocated block to the right */
 131	ext4_fsblk_t pright;
 132	/* flags. see above EXT4_MB_HINT_* */
 133	unsigned int flags;
 134};
 135
 136/*
 137 * Logical to physical block mapping, used by ext4_map_blocks()
 138 *
 139 * This structure is used to pass requests into ext4_map_blocks() as
 140 * well as to store the information returned by ext4_map_blocks().  It
 141 * takes less room on the stack than a struct buffer_head.
 142 */
 143#define EXT4_MAP_NEW		(1 << BH_New)
 144#define EXT4_MAP_MAPPED		(1 << BH_Mapped)
 145#define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
 146#define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
 147#define EXT4_MAP_UNINIT		(1 << BH_Uninit)
 148/* Sometimes (in the bigalloc case, from ext4_da_get_block_prep) the caller of
 149 * ext4_map_blocks wants to know whether or not the underlying cluster has
 150 * already been accounted for. EXT4_MAP_FROM_CLUSTER conveys to the caller that
 151 * the requested mapping was from previously mapped (or delayed allocated)
 152 * cluster. We use BH_AllocFromCluster only for this flag. BH_AllocFromCluster
 153 * should never appear on buffer_head's state flags.
 154 */
 155#define EXT4_MAP_FROM_CLUSTER	(1 << BH_AllocFromCluster)
 156#define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 157				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
 158				 EXT4_MAP_UNINIT | EXT4_MAP_FROM_CLUSTER)
 159
 160struct ext4_map_blocks {
 161	ext4_fsblk_t m_pblk;
 162	ext4_lblk_t m_lblk;
 163	unsigned int m_len;
 164	unsigned int m_flags;
 165};
 166
 167/*
 168 * For delayed allocation tracking
 169 */
 170struct mpage_da_data {
 171	struct inode *inode;
 172	sector_t b_blocknr;		/* start block number of extent */
 173	size_t b_size;			/* size of extent */
 174	unsigned long b_state;		/* state of the extent */
 175	unsigned long first_page, next_page;	/* extent of pages */
 176	struct writeback_control *wbc;
 177	int io_done;
 178	int pages_written;
 179	int retval;
 180};
 181
 182/*
 183 * Flags for ext4_io_end->flags
 184 */
 185#define	EXT4_IO_END_UNWRITTEN	0x0001
 186#define EXT4_IO_END_ERROR	0x0002
 187#define EXT4_IO_END_QUEUED	0x0004
 188#define EXT4_IO_END_DIRECT	0x0008
 189#define EXT4_IO_END_IN_FSYNC	0x0010
 190
 191struct ext4_io_page {
 192	struct page	*p_page;
 193	atomic_t	p_count;
 194};
 195
 196#define MAX_IO_PAGES 128
 197
 198/*
 199 * For converting uninitialized extents on a work queue.
 200 *
 201 * 'page' is only used from the writepage() path; 'pages' is only used for
 202 * buffered writes; they are used to keep page references until conversion
 203 * takes place.  For AIO/DIO, neither field is filled in.
 204 */
 205typedef struct ext4_io_end {
 206	struct list_head	list;		/* per-file finished IO list */
 
 
 207	struct inode		*inode;		/* file being written to */
 
 
 208	unsigned int		flag;		/* unwritten or not */
 209	struct page		*page;		/* for writepage() path */
 210	loff_t			offset;		/* offset in the file */
 211	ssize_t			size;		/* size of the extent */
 212	struct work_struct	work;		/* data work queue */
 213	struct kiocb		*iocb;		/* iocb struct for AIO */
 214	int			result;		/* error value for AIO */
 215	int			num_io_pages;   /* for writepages() */
 216	struct ext4_io_page	*pages[MAX_IO_PAGES]; /* for writepages() */
 217} ext4_io_end_t;
 218
 219struct ext4_io_submit {
 220	int			io_op;
 221	struct bio		*io_bio;
 222	ext4_io_end_t		*io_end;
 223	struct ext4_io_page	*io_page;
 224	sector_t		io_next_block;
 225};
 226
 227/*
 228 * Special inodes numbers
 229 */
 230#define	EXT4_BAD_INO		 1	/* Bad blocks inode */
 231#define EXT4_ROOT_INO		 2	/* Root inode */
 232#define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
 233#define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
 234#define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
 235#define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
 236#define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
 237#define EXT4_JOURNAL_INO	 8	/* Journal inode */
 238
 239/* First non-reserved inode for old ext4 filesystems */
 240#define EXT4_GOOD_OLD_FIRST_INO	11
 241
 242/*
 243 * Maximal count of links to a file
 244 */
 245#define EXT4_LINK_MAX		65000
 246
 247/*
 248 * Macro-instructions used to manage several block sizes
 249 */
 250#define EXT4_MIN_BLOCK_SIZE		1024
 251#define	EXT4_MAX_BLOCK_SIZE		65536
 252#define EXT4_MIN_BLOCK_LOG_SIZE		10
 253#define EXT4_MAX_BLOCK_LOG_SIZE		16
 254#ifdef __KERNEL__
 255# define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
 256#else
 257# define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 258#endif
 259#define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 260#define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
 261					 EXT4_SB(s)->s_cluster_bits)
 262#ifdef __KERNEL__
 263# define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
 264# define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
 265#else
 266# define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
 267#endif
 268#ifdef __KERNEL__
 269#define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
 270#define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
 271#define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
 272#else
 273#define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 274				 EXT4_GOOD_OLD_INODE_SIZE : \
 275				 (s)->s_inode_size)
 276#define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 277				 EXT4_GOOD_OLD_FIRST_INO : \
 278				 (s)->s_first_ino)
 279#endif
 280#define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
 281
 282/* Translate a block number to a cluster number */
 283#define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
 284/* Translate a cluster number to a block number */
 285#define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
 286/* Translate # of blks to # of clusters */
 287#define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
 288				 (sbi)->s_cluster_bits)
 
 
 
 
 
 
 
 
 
 
 289
 290/*
 291 * Structure of a blocks group descriptor
 292 */
 293struct ext4_group_desc
 294{
 295	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
 296	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
 297	__le32	bg_inode_table_lo;	/* Inodes table block */
 298	__le16	bg_free_blocks_count_lo;/* Free blocks count */
 299	__le16	bg_free_inodes_count_lo;/* Free inodes count */
 300	__le16	bg_used_dirs_count_lo;	/* Directories count */
 301	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
 302	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
 303	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
 304	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
 305	__le16  bg_itable_unused_lo;	/* Unused inodes count */
 306	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
 307	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
 308	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
 309	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
 310	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
 311	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
 312	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
 313	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 314	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
 315	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
 316	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
 317	__u32   bg_reserved;
 318};
 319
 320#define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
 321	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
 322	 sizeof(__le16))
 323#define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
 324	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
 325	 sizeof(__le16))
 326
 327/*
 328 * Structure of a flex block group info
 329 */
 330
 331struct flex_groups {
 332	atomic_t free_inodes;
 333	atomic_t free_clusters;
 334	atomic_t used_dirs;
 335};
 336
 337#define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
 338#define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
 339#define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
 340
 341/*
 342 * Macro-instructions used to manage group descriptors
 343 */
 344#define EXT4_MIN_DESC_SIZE		32
 345#define EXT4_MIN_DESC_SIZE_64BIT	64
 346#define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
 347#define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
 348#ifdef __KERNEL__
 349# define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
 350# define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
 351# define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
 352# define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
 353# define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
 354#else
 355# define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
 356# define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 357# define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
 358#endif
 359
 360/*
 361 * Constants relative to the data blocks
 362 */
 363#define	EXT4_NDIR_BLOCKS		12
 364#define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
 365#define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
 366#define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
 367#define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
 368
 369/*
 370 * Inode flags
 371 */
 372#define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
 373#define	EXT4_UNRM_FL			0x00000002 /* Undelete */
 374#define	EXT4_COMPR_FL			0x00000004 /* Compress file */
 375#define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
 376#define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
 377#define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
 378#define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
 379#define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
 380/* Reserved for compression usage... */
 381#define EXT4_DIRTY_FL			0x00000100
 382#define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
 383#define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
 384#define EXT4_ECOMPR_FL			0x00000800 /* Compression error */
 385/* End compression flags --- maybe not all used */
 386#define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
 387#define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
 388#define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
 389#define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
 390#define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
 391#define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
 392#define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 393#define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
 394#define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
 395#define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
 
 396#define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
 397
 398#define EXT4_FL_USER_VISIBLE		0x004BDFFF /* User visible flags */
 399#define EXT4_FL_USER_MODIFIABLE		0x004B80FF /* User modifiable flags */
 400
 401/* Flags that should be inherited by new inodes from their parent. */
 402#define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 403			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 404			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 405			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 406
 407/* Flags that are appropriate for regular files (all but dir-specific ones). */
 408#define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 409
 410/* Flags that are appropriate for non-directories/regular files. */
 411#define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 412
 413/* Mask out flags that are inappropriate for the given type of inode. */
 414static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 415{
 416	if (S_ISDIR(mode))
 417		return flags;
 418	else if (S_ISREG(mode))
 419		return flags & EXT4_REG_FLMASK;
 420	else
 421		return flags & EXT4_OTHER_FLMASK;
 422}
 423
 424/*
 425 * Inode flags used for atomic set/get
 426 */
 427enum {
 428	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
 429	EXT4_INODE_UNRM		= 1,	/* Undelete */
 430	EXT4_INODE_COMPR	= 2,	/* Compress file */
 431	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
 432	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
 433	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
 434	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
 435	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
 436/* Reserved for compression usage... */
 437	EXT4_INODE_DIRTY	= 8,
 438	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
 439	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
 440	EXT4_INODE_ECOMPR	= 11,	/* Compression error */
 441/* End compression flags --- maybe not all used */
 442	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
 443	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
 444	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
 445	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
 446	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
 447	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
 448	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
 449	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
 450	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
 451	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
 
 452	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
 453};
 454
 455#define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
 456#define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \
 457	printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \
 458		EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); }
 459
 460/*
 461 * Since it's pretty easy to mix up bit numbers and hex values, and we
 462 * can't do a compile-time test for ENUM values, we use a run-time
 463 * test to make sure that EXT4_XXX_FL is consistent with respect to
 464 * EXT4_INODE_XXX.  If all is well the printk and BUG_ON will all drop
 465 * out so it won't cost any extra space in the compiled kernel image.
 466 * But it's important that these values are the same, since we are
 467 * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL
 468 * must be consistent with the values of FS_XXX_FL defined in
 469 * include/linux/fs.h and the on-disk values found in ext2, ext3, and
 470 * ext4 filesystems, and of course the values defined in e2fsprogs.
 471 *
 472 * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
 473 */
 
 
 
 474static inline void ext4_check_flag_values(void)
 475{
 476	CHECK_FLAG_VALUE(SECRM);
 477	CHECK_FLAG_VALUE(UNRM);
 478	CHECK_FLAG_VALUE(COMPR);
 479	CHECK_FLAG_VALUE(SYNC);
 480	CHECK_FLAG_VALUE(IMMUTABLE);
 481	CHECK_FLAG_VALUE(APPEND);
 482	CHECK_FLAG_VALUE(NODUMP);
 483	CHECK_FLAG_VALUE(NOATIME);
 484	CHECK_FLAG_VALUE(DIRTY);
 485	CHECK_FLAG_VALUE(COMPRBLK);
 486	CHECK_FLAG_VALUE(NOCOMPR);
 487	CHECK_FLAG_VALUE(ECOMPR);
 488	CHECK_FLAG_VALUE(INDEX);
 489	CHECK_FLAG_VALUE(IMAGIC);
 490	CHECK_FLAG_VALUE(JOURNAL_DATA);
 491	CHECK_FLAG_VALUE(NOTAIL);
 492	CHECK_FLAG_VALUE(DIRSYNC);
 493	CHECK_FLAG_VALUE(TOPDIR);
 494	CHECK_FLAG_VALUE(HUGE_FILE);
 495	CHECK_FLAG_VALUE(EXTENTS);
 496	CHECK_FLAG_VALUE(EA_INODE);
 497	CHECK_FLAG_VALUE(EOFBLOCKS);
 
 498	CHECK_FLAG_VALUE(RESERVED);
 499}
 500
 501/* Used to pass group descriptor data when online resize is done */
 502struct ext4_new_group_input {
 503	__u32 group;		/* Group number for this data */
 504	__u64 block_bitmap;	/* Absolute block number of block bitmap */
 505	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
 506	__u64 inode_table;	/* Absolute block number of inode table start */
 507	__u32 blocks_count;	/* Total number of blocks in this group */
 508	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
 509	__u16 unused;
 510};
 511
 512#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 513struct compat_ext4_new_group_input {
 514	u32 group;
 515	compat_u64 block_bitmap;
 516	compat_u64 inode_bitmap;
 517	compat_u64 inode_table;
 518	u32 blocks_count;
 519	u16 reserved_blocks;
 520	u16 unused;
 521};
 522#endif
 523
 524/* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 525struct ext4_new_group_data {
 526	__u32 group;
 527	__u64 block_bitmap;
 528	__u64 inode_bitmap;
 529	__u64 inode_table;
 530	__u32 blocks_count;
 531	__u16 reserved_blocks;
 532	__u16 unused;
 533	__u32 free_blocks_count;
 534};
 535
 536/* Indexes used to index group tables in ext4_new_group_data */
 537enum {
 538	BLOCK_BITMAP = 0,	/* block bitmap */
 539	INODE_BITMAP,		/* inode bitmap */
 540	INODE_TABLE,		/* inode tables */
 541	GROUP_TABLE_COUNT,
 542};
 543
 544/*
 545 * Flags used by ext4_map_blocks()
 546 */
 547	/* Allocate any needed blocks and/or convert an unitialized
 548	   extent to be an initialized ext4 */
 549#define EXT4_GET_BLOCKS_CREATE			0x0001
 550	/* Request the creation of an unitialized extent */
 551#define EXT4_GET_BLOCKS_UNINIT_EXT		0x0002
 552#define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT	(EXT4_GET_BLOCKS_UNINIT_EXT|\
 553						 EXT4_GET_BLOCKS_CREATE)
 554	/* Caller is from the delayed allocation writeout path,
 555	   so set the magic i_delalloc_reserve_flag after taking the
 556	   inode allocation semaphore for */
 557#define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
 558	/* caller is from the direct IO path, request to creation of an
 559	unitialized extents if not allocated, split the uninitialized
 560	extent if blocks has been preallocated already*/
 561#define EXT4_GET_BLOCKS_PRE_IO			0x0008
 562#define EXT4_GET_BLOCKS_CONVERT			0x0010
 563#define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
 564					 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 565	/* Convert extent to initialized after IO complete */
 566#define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
 567					 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 568	/* Punch out blocks of an extent */
 569#define EXT4_GET_BLOCKS_PUNCH_OUT_EXT		0x0020
 
 570	/* Don't normalize allocation size (used for fallocate) */
 571#define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
 572	/* Request will not result in inode size update (user for fallocate) */
 573#define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 574
 575/*
 576 * Flags used by ext4_free_blocks
 577 */
 578#define EXT4_FREE_BLOCKS_METADATA	0x0001
 579#define EXT4_FREE_BLOCKS_FORGET		0x0002
 580#define EXT4_FREE_BLOCKS_VALIDATED	0x0004
 581#define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE	0x0008
 582#define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
 583#define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
 584
 585/*
 586 * Flags used by ext4_discard_partial_page_buffers
 587 */
 588#define EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED	0x0001
 589
 590/*
 591 * ioctl commands
 592 */
 593#define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
 594#define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
 595#define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
 596#define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
 597#define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
 598#define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
 599#define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
 600#define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
 601#define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
 602#define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
 603#define EXT4_IOC_MIGRATE		_IO('f', 9)
 604 /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 605 /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 606#define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
 607#define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
 608#define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
 
 
 609
 610#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 611/*
 612 * ioctl commands in 32 bit emulation
 613 */
 614#define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
 615#define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
 616#define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
 617#define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
 618#define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
 619#define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
 620#define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
 621#define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
 622#define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
 623#define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
 624#endif
 625
 626/* Max physical block we can address w/o extents */
 627#define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
 628
 629/*
 630 * Structure of an inode on the disk
 631 */
 632struct ext4_inode {
 633	__le16	i_mode;		/* File mode */
 634	__le16	i_uid;		/* Low 16 bits of Owner Uid */
 635	__le32	i_size_lo;	/* Size in bytes */
 636	__le32	i_atime;	/* Access time */
 637	__le32	i_ctime;	/* Inode Change time */
 638	__le32	i_mtime;	/* Modification time */
 639	__le32	i_dtime;	/* Deletion Time */
 640	__le16	i_gid;		/* Low 16 bits of Group Id */
 641	__le16	i_links_count;	/* Links count */
 642	__le32	i_blocks_lo;	/* Blocks count */
 643	__le32	i_flags;	/* File flags */
 644	union {
 645		struct {
 646			__le32  l_i_version;
 647		} linux1;
 648		struct {
 649			__u32  h_i_translator;
 650		} hurd1;
 651		struct {
 652			__u32  m_i_reserved1;
 653		} masix1;
 654	} osd1;				/* OS dependent 1 */
 655	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 656	__le32	i_generation;	/* File version (for NFS) */
 657	__le32	i_file_acl_lo;	/* File ACL */
 658	__le32	i_size_high;
 659	__le32	i_obso_faddr;	/* Obsoleted fragment address */
 660	union {
 661		struct {
 662			__le16	l_i_blocks_high; /* were l_i_reserved1 */
 663			__le16	l_i_file_acl_high;
 664			__le16	l_i_uid_high;	/* these 2 fields */
 665			__le16	l_i_gid_high;	/* were reserved2[0] */
 666			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
 667			__le16	l_i_reserved;
 668		} linux2;
 669		struct {
 670			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
 671			__u16	h_i_mode_high;
 672			__u16	h_i_uid_high;
 673			__u16	h_i_gid_high;
 674			__u32	h_i_author;
 675		} hurd2;
 676		struct {
 677			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
 678			__le16	m_i_file_acl_high;
 679			__u32	m_i_reserved2[2];
 680		} masix2;
 681	} osd2;				/* OS dependent 2 */
 682	__le16	i_extra_isize;
 683	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
 684	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 685	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 686	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 687	__le32  i_crtime;       /* File Creation time */
 688	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 689	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
 690};
 691
 692struct move_extent {
 693	__u32 reserved;		/* should be zero */
 694	__u32 donor_fd;		/* donor file descriptor */
 695	__u64 orig_start;	/* logical start offset in block for orig */
 696	__u64 donor_start;	/* logical start offset in block for donor */
 697	__u64 len;		/* block length to be moved */
 698	__u64 moved_len;	/* moved block length */
 699};
 700
 701#define EXT4_EPOCH_BITS 2
 702#define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 703#define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 704
 705/*
 706 * Extended fields will fit into an inode if the filesystem was formatted
 707 * with large inodes (-I 256 or larger) and there are not currently any EAs
 708 * consuming all of the available space. For new inodes we always reserve
 709 * enough space for the kernel's known extended fields, but for inodes
 710 * created with an old kernel this might not have been the case. None of
 711 * the extended inode fields is critical for correct filesystem operation.
 712 * This macro checks if a certain field fits in the inode. Note that
 713 * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 714 */
 715#define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
 716	((offsetof(typeof(*ext4_inode), field) +	\
 717	  sizeof((ext4_inode)->field))			\
 718	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
 719	    (einode)->i_extra_isize))			\
 720
 721static inline __le32 ext4_encode_extra_time(struct timespec *time)
 722{
 723       return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 724			   (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
 725                          ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 726}
 727
 728static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 729{
 730       if (sizeof(time->tv_sec) > 4)
 731	       time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 732			       << 32;
 733       time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 734}
 735
 736#define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)			       \
 737do {									       \
 738	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	       \
 739	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 740		(raw_inode)->xtime ## _extra =				       \
 741				ext4_encode_extra_time(&(inode)->xtime);       \
 742} while (0)
 743
 744#define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
 745do {									       \
 746	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
 747		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 748	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
 749		(raw_inode)->xtime ## _extra =				       \
 750				ext4_encode_extra_time(&(einode)->xtime);      \
 751} while (0)
 752
 753#define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)			       \
 754do {									       \
 755	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 756	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 757		ext4_decode_extra_time(&(inode)->xtime,			       \
 758				       raw_inode->xtime ## _extra);	       \
 759	else								       \
 760		(inode)->xtime.tv_nsec = 0;				       \
 761} while (0)
 762
 763#define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
 764do {									       \
 765	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
 766		(einode)->xtime.tv_sec = 				       \
 767			(signed)le32_to_cpu((raw_inode)->xtime);	       \
 
 
 768	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
 769		ext4_decode_extra_time(&(einode)->xtime,		       \
 770				       raw_inode->xtime ## _extra);	       \
 771	else								       \
 772		(einode)->xtime.tv_nsec = 0;				       \
 773} while (0)
 774
 775#define i_disk_version osd1.linux1.l_i_version
 776
 777#if defined(__KERNEL__) || defined(__linux__)
 778#define i_reserved1	osd1.linux1.l_i_reserved1
 779#define i_file_acl_high	osd2.linux2.l_i_file_acl_high
 780#define i_blocks_high	osd2.linux2.l_i_blocks_high
 781#define i_uid_low	i_uid
 782#define i_gid_low	i_gid
 783#define i_uid_high	osd2.linux2.l_i_uid_high
 784#define i_gid_high	osd2.linux2.l_i_gid_high
 785#define i_checksum_lo	osd2.linux2.l_i_checksum_lo
 786
 787#elif defined(__GNU__)
 788
 789#define i_translator	osd1.hurd1.h_i_translator
 790#define i_uid_high	osd2.hurd2.h_i_uid_high
 791#define i_gid_high	osd2.hurd2.h_i_gid_high
 792#define i_author	osd2.hurd2.h_i_author
 793
 794#elif defined(__masix__)
 795
 796#define i_reserved1	osd1.masix1.m_i_reserved1
 797#define i_file_acl_high	osd2.masix2.m_i_file_acl_high
 798#define i_reserved2	osd2.masix2.m_i_reserved2
 799
 800#endif /* defined(__KERNEL__) || defined(__linux__) */
 801
 802/*
 803 * storage for cached extent
 804 * If ec_len == 0, then the cache is invalid.
 805 * If ec_start == 0, then the cache represents a gap (null mapping)
 806 */
 807struct ext4_ext_cache {
 808	ext4_fsblk_t	ec_start;
 809	ext4_lblk_t	ec_block;
 810	__u32		ec_len; /* must be 32bit to return holes */
 811};
 812
 813/*
 814 * fourth extended file system inode data in memory
 815 */
 816struct ext4_inode_info {
 817	__le32	i_data[15];	/* unconverted */
 818	__u32	i_dtime;
 819	ext4_fsblk_t	i_file_acl;
 820
 821	/*
 822	 * i_block_group is the number of the block group which contains
 823	 * this file's inode.  Constant across the lifetime of the inode,
 824	 * it is ued for making block allocation decisions - we try to
 825	 * place a file's data blocks near its inode block, and new inodes
 826	 * near to their parent directory's inode.
 827	 */
 828	ext4_group_t	i_block_group;
 829	ext4_lblk_t	i_dir_start_lookup;
 830#if (BITS_PER_LONG < 64)
 831	unsigned long	i_state_flags;		/* Dynamic state flags */
 832#endif
 833	unsigned long	i_flags;
 834
 835#ifdef CONFIG_EXT4_FS_XATTR
 836	/*
 837	 * Extended attributes can be read independently of the main file
 838	 * data. Taking i_mutex even when reading would cause contention
 839	 * between readers of EAs and writers of regular file data, so
 840	 * instead we synchronize on xattr_sem when reading or changing
 841	 * EAs.
 842	 */
 843	struct rw_semaphore xattr_sem;
 844#endif
 845
 846	struct list_head i_orphan;	/* unlinked but open inodes */
 847
 848	/*
 849	 * i_disksize keeps track of what the inode size is ON DISK, not
 850	 * in memory.  During truncate, i_size is set to the new size by
 851	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
 852	 * set i_disksize to 0 until the truncate is actually under way.
 853	 *
 854	 * The intent is that i_disksize always represents the blocks which
 855	 * are used by this file.  This allows recovery to restart truncate
 856	 * on orphans if we crash during truncate.  We actually write i_disksize
 857	 * into the on-disk inode when writing inodes out, instead of i_size.
 858	 *
 859	 * The only time when i_disksize and i_size may be different is when
 860	 * a truncate is in progress.  The only things which change i_disksize
 861	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
 862	 */
 863	loff_t	i_disksize;
 864
 865	/*
 866	 * i_data_sem is for serialising ext4_truncate() against
 867	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
 868	 * data tree are chopped off during truncate. We can't do that in
 869	 * ext4 because whenever we perform intermediate commits during
 870	 * truncate, the inode and all the metadata blocks *must* be in a
 871	 * consistent state which allows truncation of the orphans to restart
 872	 * during recovery.  Hence we must fix the get_block-vs-truncate race
 873	 * by other means, so we have i_data_sem.
 874	 */
 875	struct rw_semaphore i_data_sem;
 876	struct inode vfs_inode;
 877	struct jbd2_inode *jinode;
 878
 879	struct ext4_ext_cache i_cached_extent;
 880	/*
 881	 * File creation time. Its function is same as that of
 882	 * struct timespec i_{a,c,m}time in the generic inode.
 883	 */
 884	struct timespec i_crtime;
 885
 886	/* mballoc */
 887	struct list_head i_prealloc_list;
 888	spinlock_t i_prealloc_lock;
 889
 
 
 
 
 
 
 
 890	/* ialloc */
 891	ext4_group_t	i_last_alloc_group;
 892
 893	/* allocation reservation info for delalloc */
 894	/* In case of bigalloc, these refer to clusters rather than blocks */
 895	unsigned int i_reserved_data_blocks;
 896	unsigned int i_reserved_meta_blocks;
 897	unsigned int i_allocated_meta_blocks;
 898	ext4_lblk_t i_da_metadata_calc_last_lblock;
 899	int i_da_metadata_calc_len;
 900
 901	/* on-disk additional length */
 902	__u16 i_extra_isize;
 903
 
 
 
 
 904#ifdef CONFIG_QUOTA
 905	/* quota space reservation, managed internally by quota code */
 906	qsize_t i_reserved_quota;
 907#endif
 908
 909	/* completed IOs that might need unwritten extents handling */
 910	struct list_head i_completed_io_list;
 911	spinlock_t i_completed_io_lock;
 
 
 
 
 
 
 
 
 
 912	atomic_t i_ioend_count;	/* Number of outstanding io_end structs */
 913	/* current io_end structure for async DIO write*/
 914	ext4_io_end_t *cur_aio_dio;
 915	atomic_t i_aiodio_unwritten; /* Nr. of inflight conversions pending */
 916
 917	spinlock_t i_block_reservation_lock;
 918
 919	/*
 920	 * Transactions that contain inode's metadata needed to complete
 921	 * fsync and fdatasync, respectively.
 922	 */
 923	tid_t i_sync_tid;
 924	tid_t i_datasync_tid;
 925
 926	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
 927	__u32 i_csum_seed;
 928};
 929
 930/*
 931 * File system states
 932 */
 933#define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
 934#define	EXT4_ERROR_FS			0x0002	/* Errors detected */
 935#define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
 936
 937/*
 938 * Misc. filesystem flags
 939 */
 940#define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
 941#define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
 942#define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
 943
 944/*
 945 * Mount flags
 946 */
 947#define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
 948#define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
 949#define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
 950#define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
 951#define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
 952#define EXT4_MOUNT_ERRORS_MASK		0x00070
 953#define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
 954#define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
 955#define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
 956#define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
 957#define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
 958#define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
 959#define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
 960#define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
 961#define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
 962#define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
 963#define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
 964#define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
 965#define EXT4_MOUNT_QUOTA		0x80000 /* Some quota option set */
 966#define EXT4_MOUNT_USRQUOTA		0x100000 /* "old" user quota */
 967#define EXT4_MOUNT_GRPQUOTA		0x200000 /* "old" group quota */
 968#define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
 969#define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
 970#define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
 971#define EXT4_MOUNT_MBLK_IO_SUBMIT	0x4000000 /* multi-block io submits */
 972#define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
 973#define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
 974#define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
 975#define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
 976#define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
 977
 
 
 
 
 
 978#define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
 979						      specified delalloc */
 
 
 
 
 
 980
 981#define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
 982						~EXT4_MOUNT_##opt
 983#define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
 984						EXT4_MOUNT_##opt
 985#define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
 986					 EXT4_MOUNT_##opt)
 987
 988#define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
 989						~EXT4_MOUNT2_##opt
 990#define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
 991						EXT4_MOUNT2_##opt
 992#define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
 993					 EXT4_MOUNT2_##opt)
 994
 995#define ext4_test_and_set_bit		__test_and_set_bit_le
 996#define ext4_set_bit			__set_bit_le
 997#define ext4_set_bit_atomic		ext2_set_bit_atomic
 998#define ext4_test_and_clear_bit		__test_and_clear_bit_le
 999#define ext4_clear_bit			__clear_bit_le
1000#define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1001#define ext4_test_bit			test_bit_le
1002#define ext4_find_next_zero_bit		find_next_zero_bit_le
1003#define ext4_find_next_bit		find_next_bit_le
1004
1005extern void ext4_set_bits(void *bm, int cur, int len);
1006
1007/*
1008 * Maximal mount counts between two filesystem checks
1009 */
1010#define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1011#define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1012
1013/*
1014 * Behaviour when detecting errors
1015 */
1016#define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1017#define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1018#define EXT4_ERRORS_PANIC		3	/* Panic */
1019#define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1020
1021/* Metadata checksum algorithm codes */
1022#define EXT4_CRC32C_CHKSUM		1
1023
1024/*
1025 * Structure of the super block
1026 */
1027struct ext4_super_block {
1028/*00*/	__le32	s_inodes_count;		/* Inodes count */
1029	__le32	s_blocks_count_lo;	/* Blocks count */
1030	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1031	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1032/*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1033	__le32	s_first_data_block;	/* First Data Block */
1034	__le32	s_log_block_size;	/* Block size */
1035	__le32	s_log_cluster_size;	/* Allocation cluster size */
1036/*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1037	__le32	s_clusters_per_group;	/* # Clusters per group */
1038	__le32	s_inodes_per_group;	/* # Inodes per group */
1039	__le32	s_mtime;		/* Mount time */
1040/*30*/	__le32	s_wtime;		/* Write time */
1041	__le16	s_mnt_count;		/* Mount count */
1042	__le16	s_max_mnt_count;	/* Maximal mount count */
1043	__le16	s_magic;		/* Magic signature */
1044	__le16	s_state;		/* File system state */
1045	__le16	s_errors;		/* Behaviour when detecting errors */
1046	__le16	s_minor_rev_level;	/* minor revision level */
1047/*40*/	__le32	s_lastcheck;		/* time of last check */
1048	__le32	s_checkinterval;	/* max. time between checks */
1049	__le32	s_creator_os;		/* OS */
1050	__le32	s_rev_level;		/* Revision level */
1051/*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1052	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1053	/*
1054	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1055	 *
1056	 * Note: the difference between the compatible feature set and
1057	 * the incompatible feature set is that if there is a bit set
1058	 * in the incompatible feature set that the kernel doesn't
1059	 * know about, it should refuse to mount the filesystem.
1060	 *
1061	 * e2fsck's requirements are more strict; if it doesn't know
1062	 * about a feature in either the compatible or incompatible
1063	 * feature set, it must abort and not try to meddle with
1064	 * things it doesn't understand...
1065	 */
1066	__le32	s_first_ino;		/* First non-reserved inode */
1067	__le16  s_inode_size;		/* size of inode structure */
1068	__le16	s_block_group_nr;	/* block group # of this superblock */
1069	__le32	s_feature_compat;	/* compatible feature set */
1070/*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1071	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1072/*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1073/*78*/	char	s_volume_name[16];	/* volume name */
1074/*88*/	char	s_last_mounted[64];	/* directory where last mounted */
1075/*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1076	/*
1077	 * Performance hints.  Directory preallocation should only
1078	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1079	 */
1080	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1081	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1082	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1083	/*
1084	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1085	 */
1086/*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1087/*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1088	__le32	s_journal_dev;		/* device number of journal file */
1089	__le32	s_last_orphan;		/* start of list of inodes to delete */
1090	__le32	s_hash_seed[4];		/* HTREE hash seed */
1091	__u8	s_def_hash_version;	/* Default hash version to use */
1092	__u8	s_jnl_backup_type;
1093	__le16  s_desc_size;		/* size of group descriptor */
1094/*100*/	__le32	s_default_mount_opts;
1095	__le32	s_first_meta_bg;	/* First metablock block group */
1096	__le32	s_mkfs_time;		/* When the filesystem was created */
1097	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1098	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1099/*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1100	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1101	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1102	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1103	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1104	__le32	s_flags;		/* Miscellaneous flags */
1105	__le16  s_raid_stride;		/* RAID stride */
1106	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1107	__le64  s_mmp_block;            /* Block for multi-mount protection */
1108	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1109	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1110	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1111	__le16  s_reserved_pad;
1112	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1113	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1114	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1115	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1116					      snapshot's future use */
1117	__le32	s_snapshot_list;	/* inode number of the head of the
1118					   on-disk snapshot list */
1119#define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1120	__le32	s_error_count;		/* number of fs errors */
1121	__le32	s_first_error_time;	/* first time an error happened */
1122	__le32	s_first_error_ino;	/* inode involved in first error */
1123	__le64	s_first_error_block;	/* block involved of first error */
1124	__u8	s_first_error_func[32];	/* function where the error happened */
1125	__le32	s_first_error_line;	/* line number where error happened */
1126	__le32	s_last_error_time;	/* most recent time of an error */
1127	__le32	s_last_error_ino;	/* inode involved in last error */
1128	__le32	s_last_error_line;	/* line number where error happened */
1129	__le64	s_last_error_block;	/* block involved of last error */
1130	__u8	s_last_error_func[32];	/* function where the error happened */
1131#define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1132	__u8	s_mount_opts[64];
1133	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1134	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1135	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1136	__le32	s_reserved[108];	/* Padding to the end of the block */
1137	__le32	s_checksum;		/* crc32c(superblock) */
1138};
1139
1140#define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1141
1142#ifdef __KERNEL__
1143
1144/*
1145 * run-time mount flags
1146 */
1147#define EXT4_MF_MNTDIR_SAMPLED	0x0001
1148#define EXT4_MF_FS_ABORTED	0x0002	/* Fatal error detected */
1149
1150/*
1151 * fourth extended-fs super-block data in memory
1152 */
1153struct ext4_sb_info {
1154	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1155	unsigned long s_inodes_per_block;/* Number of inodes per block */
1156	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1157	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1158	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1159	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1160	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1161	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1162	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1163	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1164	unsigned long s_overhead;  /* # of fs overhead clusters */
1165	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1166	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1167	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1168	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1169	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1170	struct buffer_head **s_group_desc;
1171	unsigned int s_mount_opt;
1172	unsigned int s_mount_opt2;
1173	unsigned int s_mount_flags;
1174	unsigned int s_def_mount_opt;
1175	ext4_fsblk_t s_sb_block;
 
1176	kuid_t s_resuid;
1177	kgid_t s_resgid;
1178	unsigned short s_mount_state;
1179	unsigned short s_pad;
1180	int s_addr_per_block_bits;
1181	int s_desc_per_block_bits;
1182	int s_inode_size;
1183	int s_first_ino;
1184	unsigned int s_inode_readahead_blks;
1185	unsigned int s_inode_goal;
1186	spinlock_t s_next_gen_lock;
1187	u32 s_next_generation;
1188	u32 s_hash_seed[4];
1189	int s_def_hash_version;
1190	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1191	struct percpu_counter s_freeclusters_counter;
1192	struct percpu_counter s_freeinodes_counter;
1193	struct percpu_counter s_dirs_counter;
1194	struct percpu_counter s_dirtyclusters_counter;
1195	struct blockgroup_lock *s_blockgroup_lock;
1196	struct proc_dir_entry *s_proc;
1197	struct kobject s_kobj;
1198	struct completion s_kobj_unregister;
1199	struct super_block *s_sb;
1200
1201	/* Journaling */
1202	struct journal_s *s_journal;
1203	struct list_head s_orphan;
1204	struct mutex s_orphan_lock;
1205	unsigned long s_resize_flags;		/* Flags indicating if there
1206						   is a resizer */
1207	unsigned long s_commit_interval;
1208	u32 s_max_batch_time;
1209	u32 s_min_batch_time;
1210	struct block_device *journal_bdev;
1211#ifdef CONFIG_QUOTA
1212	char *s_qf_names[MAXQUOTAS];		/* Names of quota files with journalled quota */
1213	int s_jquota_fmt;			/* Format of quota to use */
1214#endif
1215	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1216	struct rb_root system_blks;
1217
1218#ifdef EXTENTS_STATS
1219	/* ext4 extents stats */
1220	unsigned long s_ext_min;
1221	unsigned long s_ext_max;
1222	unsigned long s_depth_max;
1223	spinlock_t s_ext_stats_lock;
1224	unsigned long s_ext_blocks;
1225	unsigned long s_ext_extents;
1226#endif
1227
1228	/* for buddy allocator */
1229	struct ext4_group_info ***s_group_info;
1230	struct inode *s_buddy_cache;
1231	spinlock_t s_md_lock;
1232	unsigned short *s_mb_offsets;
1233	unsigned int *s_mb_maxs;
 
1234
1235	/* tunables */
1236	unsigned long s_stripe;
1237	unsigned int s_mb_stream_request;
1238	unsigned int s_mb_max_to_scan;
1239	unsigned int s_mb_min_to_scan;
1240	unsigned int s_mb_stats;
1241	unsigned int s_mb_order2_reqs;
1242	unsigned int s_mb_group_prealloc;
1243	unsigned int s_max_writeback_mb_bump;
1244	/* where last allocation was done - for stream allocation */
1245	unsigned long s_mb_last_group;
1246	unsigned long s_mb_last_start;
1247
1248	/* stats for buddy allocator */
1249	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1250	atomic_t s_bal_success;	/* we found long enough chunks */
1251	atomic_t s_bal_allocated;	/* in blocks */
1252	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1253	atomic_t s_bal_goals;	/* goal hits */
1254	atomic_t s_bal_breaks;	/* too long searches */
1255	atomic_t s_bal_2orders;	/* 2^order hits */
1256	spinlock_t s_bal_lock;
1257	unsigned long s_mb_buddies_generated;
1258	unsigned long long s_mb_generation_time;
1259	atomic_t s_mb_lost_chunks;
1260	atomic_t s_mb_preallocated;
1261	atomic_t s_mb_discarded;
1262	atomic_t s_lock_busy;
1263
1264	/* locality groups */
1265	struct ext4_locality_group __percpu *s_locality_groups;
1266
1267	/* for write statistics */
1268	unsigned long s_sectors_written_start;
1269	u64 s_kbytes_written;
1270
 
 
 
1271	unsigned int s_log_groups_per_flex;
1272	struct flex_groups *s_flex_groups;
 
1273
1274	/* workqueue for dio unwritten */
1275	struct workqueue_struct *dio_unwritten_wq;
1276
1277	/* timer for periodic error stats printing */
1278	struct timer_list s_err_report;
1279
1280	/* Lazy inode table initialization info */
1281	struct ext4_li_request *s_li_request;
1282	/* Wait multiplier for lazy initialization thread */
1283	unsigned int s_li_wait_mult;
1284
1285	/* Kernel thread for multiple mount protection */
1286	struct task_struct *s_mmp_tsk;
1287
1288	/* record the last minlen when FITRIM is called. */
1289	atomic_t s_last_trim_minblks;
1290
1291	/* Reference to checksum algorithm driver via cryptoapi */
1292	struct crypto_shash *s_chksum_driver;
1293
1294	/* Precomputed FS UUID checksum for seeding other checksums */
1295	__u32 s_csum_seed;
 
 
 
 
 
 
 
 
 
 
 
 
 
1296};
1297
1298static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1299{
1300	return sb->s_fs_info;
1301}
1302static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1303{
1304	return container_of(inode, struct ext4_inode_info, vfs_inode);
1305}
1306
1307static inline struct timespec ext4_current_time(struct inode *inode)
1308{
1309	return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1310		current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1311}
1312
1313static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1314{
1315	return ino == EXT4_ROOT_INO ||
 
 
 
1316		ino == EXT4_JOURNAL_INO ||
1317		ino == EXT4_RESIZE_INO ||
1318		(ino >= EXT4_FIRST_INO(sb) &&
1319		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1320}
1321
1322static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1323					      struct ext4_io_end *io_end)
1324{
1325	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1326		io_end->flag |= EXT4_IO_END_UNWRITTEN;
1327		atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
1328	}
1329}
1330
 
 
 
 
 
 
 
 
 
 
1331/*
1332 * Inode dynamic state flags
1333 */
1334enum {
1335	EXT4_STATE_JDATA,		/* journaled data exists */
1336	EXT4_STATE_NEW,			/* inode is newly created */
1337	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1338	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1339	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1340	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1341	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1342	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1343	EXT4_STATE_DELALLOC_RESERVED,	/* blks already reserved for delalloc */
 
 
 
 
 
1344};
1345
1346#define EXT4_INODE_BIT_FNS(name, field, offset)				\
1347static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1348{									\
1349	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1350}									\
1351static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1352{									\
1353	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1354}									\
1355static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1356{									\
1357	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1358}
1359
 
 
 
 
 
1360EXT4_INODE_BIT_FNS(flag, flags, 0)
 
 
 
 
 
 
1361#if (BITS_PER_LONG < 64)
1362EXT4_INODE_BIT_FNS(state, state_flags, 0)
1363
1364static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1365{
1366	(ei)->i_state_flags = 0;
1367}
1368#else
1369EXT4_INODE_BIT_FNS(state, flags, 32)
1370
1371static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1372{
1373	/* We depend on the fact that callers will set i_flags */
1374}
1375#endif
1376#else
1377/* Assume that user mode programs are passing in an ext4fs superblock, not
1378 * a kernel struct super_block.  This will allow us to call the feature-test
1379 * macros from user land. */
1380#define EXT4_SB(sb)	(sb)
1381#endif
1382
1383#define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1384
1385/*
1386 * Codes for operating systems
1387 */
1388#define EXT4_OS_LINUX		0
1389#define EXT4_OS_HURD		1
1390#define EXT4_OS_MASIX		2
1391#define EXT4_OS_FREEBSD		3
1392#define EXT4_OS_LITES		4
1393
1394/*
1395 * Revision levels
1396 */
1397#define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1398#define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1399
1400#define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1401#define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1402
1403#define EXT4_GOOD_OLD_INODE_SIZE 128
1404
1405/*
1406 * Feature set definitions
1407 */
1408
1409#define EXT4_HAS_COMPAT_FEATURE(sb,mask)			\
1410	((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1411#define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)			\
1412	((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1413#define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)			\
1414	((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1415#define EXT4_SET_COMPAT_FEATURE(sb,mask)			\
1416	EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1417#define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)			\
1418	EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1419#define EXT4_SET_INCOMPAT_FEATURE(sb,mask)			\
1420	EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1421#define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)			\
1422	EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1423#define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
1424	EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1425#define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
1426	EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1427
1428#define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1429#define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1430#define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1431#define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1432#define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1433#define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1434
1435#define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1436#define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1437#define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1438#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1439#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1440#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1441#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1442#define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1443#define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1444/*
1445 * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1446 * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1447 * all other data structures' checksums.  However, the METADATA_CSUM and
1448 * GDT_CSUM bits are mutually exclusive.
1449 */
1450#define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1451
1452#define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1453#define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1454#define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1455#define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1456#define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1457#define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1458#define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1459#define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1460#define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1461#define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1462#define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1463#define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM	0x2000 /* use crc32c for bg */
1464#define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1465#define EXT4_FEATURE_INCOMPAT_INLINEDATA	0x8000 /* data in inode */
1466
1467#define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1468#define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1469					 EXT4_FEATURE_INCOMPAT_META_BG)
1470#define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1471					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1472					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1473
1474#define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1475#define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1476					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1477					 EXT4_FEATURE_INCOMPAT_META_BG)
1478#define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1479					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1480					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1481
1482#define EXT4_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR
1483#define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1484					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1485					 EXT4_FEATURE_INCOMPAT_META_BG| \
1486					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1487					 EXT4_FEATURE_INCOMPAT_64BIT| \
1488					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1489					 EXT4_FEATURE_INCOMPAT_MMP)
 
1490#define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1491					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1492					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1493					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1494					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1495					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1496					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1497					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1498					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)
 
1499
1500/*
1501 * Default values for user and/or group using reserved blocks
1502 */
1503#define	EXT4_DEF_RESUID		0
1504#define	EXT4_DEF_RESGID		0
1505
1506#define EXT4_DEF_INODE_READAHEAD_BLKS	32
1507
1508/*
1509 * Default mount options
1510 */
1511#define EXT4_DEFM_DEBUG		0x0001
1512#define EXT4_DEFM_BSDGROUPS	0x0002
1513#define EXT4_DEFM_XATTR_USER	0x0004
1514#define EXT4_DEFM_ACL		0x0008
1515#define EXT4_DEFM_UID16		0x0010
1516#define EXT4_DEFM_JMODE		0x0060
1517#define EXT4_DEFM_JMODE_DATA	0x0020
1518#define EXT4_DEFM_JMODE_ORDERED	0x0040
1519#define EXT4_DEFM_JMODE_WBACK	0x0060
1520#define EXT4_DEFM_NOBARRIER	0x0100
1521#define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1522#define EXT4_DEFM_DISCARD	0x0400
1523#define EXT4_DEFM_NODELALLOC	0x0800
1524
1525/*
1526 * Default journal batch times
1527 */
1528#define EXT4_DEF_MIN_BATCH_TIME	0
1529#define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1530
1531/*
1532 * Minimum number of groups in a flexgroup before we separate out
1533 * directories into the first block group of a flexgroup
1534 */
1535#define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1536
1537/*
1538 * Structure of a directory entry
1539 */
1540#define EXT4_NAME_LEN 255
1541
1542struct ext4_dir_entry {
1543	__le32	inode;			/* Inode number */
1544	__le16	rec_len;		/* Directory entry length */
1545	__le16	name_len;		/* Name length */
1546	char	name[EXT4_NAME_LEN];	/* File name */
1547};
1548
1549/*
1550 * The new version of the directory entry.  Since EXT4 structures are
1551 * stored in intel byte order, and the name_len field could never be
1552 * bigger than 255 chars, it's safe to reclaim the extra byte for the
1553 * file_type field.
1554 */
1555struct ext4_dir_entry_2 {
1556	__le32	inode;			/* Inode number */
1557	__le16	rec_len;		/* Directory entry length */
1558	__u8	name_len;		/* Name length */
1559	__u8	file_type;
1560	char	name[EXT4_NAME_LEN];	/* File name */
1561};
1562
1563/*
1564 * This is a bogus directory entry at the end of each leaf block that
1565 * records checksums.
1566 */
1567struct ext4_dir_entry_tail {
1568	__le32	det_reserved_zero1;	/* Pretend to be unused */
1569	__le16	det_rec_len;		/* 12 */
1570	__u8	det_reserved_zero2;	/* Zero name length */
1571	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1572	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1573};
1574
 
 
 
 
 
1575/*
1576 * Ext4 directory file types.  Only the low 3 bits are used.  The
1577 * other bits are reserved for now.
1578 */
1579#define EXT4_FT_UNKNOWN		0
1580#define EXT4_FT_REG_FILE	1
1581#define EXT4_FT_DIR		2
1582#define EXT4_FT_CHRDEV		3
1583#define EXT4_FT_BLKDEV		4
1584#define EXT4_FT_FIFO		5
1585#define EXT4_FT_SOCK		6
1586#define EXT4_FT_SYMLINK		7
1587
1588#define EXT4_FT_MAX		8
1589
1590#define EXT4_FT_DIR_CSUM	0xDE
1591
1592/*
1593 * EXT4_DIR_PAD defines the directory entries boundaries
1594 *
1595 * NOTE: It must be a multiple of 4
1596 */
1597#define EXT4_DIR_PAD			4
1598#define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1599#define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1600					 ~EXT4_DIR_ROUND)
1601#define EXT4_MAX_REC_LEN		((1<<16)-1)
1602
1603/*
1604 * If we ever get support for fs block sizes > page_size, we'll need
1605 * to remove the #if statements in the next two functions...
1606 */
1607static inline unsigned int
1608ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1609{
1610	unsigned len = le16_to_cpu(dlen);
1611
1612#if (PAGE_CACHE_SIZE >= 65536)
1613	if (len == EXT4_MAX_REC_LEN || len == 0)
1614		return blocksize;
1615	return (len & 65532) | ((len & 3) << 16);
1616#else
1617	return len;
1618#endif
1619}
1620
1621static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1622{
1623	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1624		BUG();
1625#if (PAGE_CACHE_SIZE >= 65536)
1626	if (len < 65536)
1627		return cpu_to_le16(len);
1628	if (len == blocksize) {
1629		if (blocksize == 65536)
1630			return cpu_to_le16(EXT4_MAX_REC_LEN);
1631		else
1632			return cpu_to_le16(0);
1633	}
1634	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1635#else
1636	return cpu_to_le16(len);
1637#endif
1638}
1639
1640/*
1641 * Hash Tree Directory indexing
1642 * (c) Daniel Phillips, 2001
1643 */
1644
1645#define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1646				      EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1647		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1648#define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1649#define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1650
1651/* Legal values for the dx_root hash_version field: */
1652
1653#define DX_HASH_LEGACY		0
1654#define DX_HASH_HALF_MD4	1
1655#define DX_HASH_TEA		2
1656#define DX_HASH_LEGACY_UNSIGNED	3
1657#define DX_HASH_HALF_MD4_UNSIGNED	4
1658#define DX_HASH_TEA_UNSIGNED		5
1659
1660static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1661			      const void *address, unsigned int length)
1662{
1663	struct {
1664		struct shash_desc shash;
1665		char ctx[crypto_shash_descsize(sbi->s_chksum_driver)];
1666	} desc;
1667	int err;
1668
 
 
1669	desc.shash.tfm = sbi->s_chksum_driver;
1670	desc.shash.flags = 0;
1671	*(u32 *)desc.ctx = crc;
1672
1673	err = crypto_shash_update(&desc.shash, address, length);
1674	BUG_ON(err);
1675
1676	return *(u32 *)desc.ctx;
1677}
1678
1679#ifdef __KERNEL__
1680
1681/* hash info structure used by the directory hash */
1682struct dx_hash_info
1683{
1684	u32		hash;
1685	u32		minor_hash;
1686	int		hash_version;
1687	u32		*seed;
1688};
1689
1690
1691/* 32 and 64 bit signed EOF for dx directories */
1692#define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1693#define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1694
1695
1696/*
1697 * Control parameters used by ext4_htree_next_block
1698 */
1699#define HASH_NB_ALWAYS		1
1700
1701
1702/*
1703 * Describe an inode's exact location on disk and in memory
1704 */
1705struct ext4_iloc
1706{
1707	struct buffer_head *bh;
1708	unsigned long offset;
1709	ext4_group_t block_group;
1710};
1711
1712static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1713{
1714	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1715}
1716
1717/*
1718 * This structure is stuffed into the struct file's private_data field
1719 * for directories.  It is where we put information so that we can do
1720 * readdir operations in hash tree order.
1721 */
1722struct dir_private_info {
1723	struct rb_root	root;
1724	struct rb_node	*curr_node;
1725	struct fname	*extra_fname;
1726	loff_t		last_pos;
1727	__u32		curr_hash;
1728	__u32		curr_minor_hash;
1729	__u32		next_hash;
1730};
1731
1732/* calculate the first block number of the group */
1733static inline ext4_fsblk_t
1734ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1735{
1736	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1737		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1738}
1739
1740/*
1741 * Special error return code only used by dx_probe() and its callers.
1742 */
1743#define ERR_BAD_DX_DIR	-75000
1744
1745void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1746			ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1747
1748/*
1749 * Timeout and state flag for lazy initialization inode thread.
1750 */
1751#define EXT4_DEF_LI_WAIT_MULT			10
1752#define EXT4_DEF_LI_MAX_START_DELAY		5
1753#define EXT4_LAZYINIT_QUIT			0x0001
1754#define EXT4_LAZYINIT_RUNNING			0x0002
1755
1756/*
1757 * Lazy inode table initialization info
1758 */
1759struct ext4_lazy_init {
1760	unsigned long		li_state;
1761	struct list_head	li_request_list;
1762	struct mutex		li_list_mtx;
1763};
1764
1765struct ext4_li_request {
1766	struct super_block	*lr_super;
1767	struct ext4_sb_info	*lr_sbi;
1768	ext4_group_t		lr_next_group;
1769	struct list_head	lr_request;
1770	unsigned long		lr_next_sched;
1771	unsigned long		lr_timeout;
1772};
1773
1774struct ext4_features {
1775	struct kobject f_kobj;
1776	struct completion f_kobj_unregister;
1777};
1778
1779/*
1780 * This structure will be used for multiple mount protection. It will be
1781 * written into the block number saved in the s_mmp_block field in the
1782 * superblock. Programs that check MMP should assume that if
1783 * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1784 * to use the filesystem, regardless of how old the timestamp is.
1785 */
1786#define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1787#define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1788#define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1789#define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1790
1791struct mmp_struct {
1792	__le32	mmp_magic;		/* Magic number for MMP */
1793	__le32	mmp_seq;		/* Sequence no. updated periodically */
1794
1795	/*
1796	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1797	 * purposes and do not affect the correctness of the algorithm
1798	 */
1799	__le64	mmp_time;		/* Time last updated */
1800	char	mmp_nodename[64];	/* Node which last updated MMP block */
1801	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
1802
1803	/*
1804	 * mmp_check_interval is used to verify if the MMP block has been
1805	 * updated on the block device. The value is updated based on the
1806	 * maximum time to write the MMP block during an update cycle.
1807	 */
1808	__le16	mmp_check_interval;
1809
1810	__le16	mmp_pad1;
1811	__le32	mmp_pad2[226];
1812	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
1813};
1814
1815/* arguments passed to the mmp thread */
1816struct mmpd_data {
1817	struct buffer_head *bh; /* bh from initial read_mmp_block() */
1818	struct super_block *sb;  /* super block of the fs */
1819};
1820
1821/*
1822 * Check interval multiplier
1823 * The MMP block is written every update interval and initially checked every
1824 * update interval x the multiplier (the value is then adapted based on the
1825 * write latency). The reason is that writes can be delayed under load and we
1826 * don't want readers to incorrectly assume that the filesystem is no longer
1827 * in use.
1828 */
1829#define EXT4_MMP_CHECK_MULT		2UL
1830
1831/*
1832 * Minimum interval for MMP checking in seconds.
1833 */
1834#define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
1835
1836/*
1837 * Maximum interval for MMP checking in seconds.
1838 */
1839#define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
1840
1841/*
1842 * Function prototypes
1843 */
1844
1845/*
1846 * Ok, these declarations are also in <linux/kernel.h> but none of the
1847 * ext4 source programs needs to include it so they are duplicated here.
1848 */
1849# define NORET_TYPE	/**/
1850# define ATTRIB_NORET	__attribute__((noreturn))
1851# define NORET_AND	noreturn,
1852
1853/* bitmap.c */
1854extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
1855void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1856				struct ext4_group_desc *gdp,
1857				struct buffer_head *bh, int sz);
1858int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1859				  struct ext4_group_desc *gdp,
1860				  struct buffer_head *bh, int sz);
1861void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1862				struct ext4_group_desc *gdp,
1863				struct buffer_head *bh, int sz);
1864int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1865				  struct ext4_group_desc *gdp,
1866				  struct buffer_head *bh, int sz);
1867
1868/* balloc.c */
 
 
 
 
 
 
 
1869extern void ext4_validate_block_bitmap(struct super_block *sb,
1870				       struct ext4_group_desc *desc,
1871				       unsigned int block_group,
1872				       struct buffer_head *bh);
1873extern unsigned int ext4_block_group(struct super_block *sb,
1874			ext4_fsblk_t blocknr);
1875extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1876			ext4_fsblk_t blocknr);
1877extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1878extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1879			ext4_group_t group);
1880extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1881					 ext4_fsblk_t goal,
1882					 unsigned int flags,
1883					 unsigned long *count,
1884					 int *errp);
1885extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1886				    s64 nclusters, unsigned int flags);
1887extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1888extern void ext4_check_blocks_bitmap(struct super_block *);
1889extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1890						    ext4_group_t block_group,
1891						    struct buffer_head ** bh);
1892extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1893
1894extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
1895						ext4_group_t block_group);
1896extern int ext4_wait_block_bitmap(struct super_block *sb,
1897				  ext4_group_t block_group,
1898				  struct buffer_head *bh);
1899extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1900						  ext4_group_t block_group);
1901extern void ext4_init_block_bitmap(struct super_block *sb,
1902				   struct buffer_head *bh,
1903				   ext4_group_t group,
1904				   struct ext4_group_desc *desc);
1905extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1906					      ext4_group_t block_group,
1907					      struct ext4_group_desc *gdp);
1908extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
1909					   ext4_group_t block_group,
1910					   struct ext4_group_desc *gdp);
1911ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1912
1913/* dir.c */
1914extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
1915				  struct file *,
1916				  struct ext4_dir_entry_2 *,
1917				  struct buffer_head *, unsigned int);
1918#define ext4_check_dir_entry(dir, filp, de, bh, offset)			\
 
1919	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
1920					(de), (bh), (offset)))
1921extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1922				    __u32 minor_hash,
1923				    struct ext4_dir_entry_2 *dirent);
1924extern void ext4_htree_free_dir_info(struct dir_private_info *p);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1925
1926/* fsync.c */
1927extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
1928extern int ext4_flush_completed_IO(struct inode *);
1929
1930/* hash.c */
1931extern int ext4fs_dirhash(const char *name, int len, struct
1932			  dx_hash_info *hinfo);
1933
1934/* ialloc.c */
1935extern struct inode *ext4_new_inode(handle_t *, struct inode *, umode_t,
1936				    const struct qstr *qstr, __u32 goal,
1937				    uid_t *owner);
 
 
 
 
 
 
 
 
 
 
 
1938extern void ext4_free_inode(handle_t *, struct inode *);
1939extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1940extern unsigned long ext4_count_free_inodes(struct super_block *);
1941extern unsigned long ext4_count_dirs(struct super_block *);
1942extern void ext4_check_inodes_bitmap(struct super_block *);
1943extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1944extern int ext4_init_inode_table(struct super_block *sb,
1945				 ext4_group_t group, int barrier);
1946extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
1947
1948/* mballoc.c */
1949extern long ext4_mb_stats;
1950extern long ext4_mb_max_to_scan;
1951extern int ext4_mb_init(struct super_block *);
1952extern int ext4_mb_release(struct super_block *);
1953extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1954				struct ext4_allocation_request *, int *);
1955extern int ext4_mb_reserve_blocks(struct super_block *, int);
1956extern void ext4_discard_preallocations(struct inode *);
1957extern int __init ext4_init_mballoc(void);
1958extern void ext4_exit_mballoc(void);
1959extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1960			     struct buffer_head *bh, ext4_fsblk_t block,
1961			     unsigned long count, int flags);
 
 
1962extern int ext4_mb_add_groupinfo(struct super_block *sb,
1963		ext4_group_t i, struct ext4_group_desc *desc);
1964extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
1965				ext4_fsblk_t block, unsigned long count);
1966extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
1967
1968/* inode.c */
1969struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1970						ext4_lblk_t, int, int *);
1971struct buffer_head *ext4_bread(handle_t *, struct inode *,
1972						ext4_lblk_t, int, int *);
 
 
1973int ext4_get_block(struct inode *inode, sector_t iblock,
1974				struct buffer_head *bh_result, int create);
 
 
 
 
 
 
 
 
 
 
 
 
 
1975
1976extern struct inode *ext4_iget(struct super_block *, unsigned long);
1977extern int  ext4_write_inode(struct inode *, struct writeback_control *);
1978extern int  ext4_setattr(struct dentry *, struct iattr *);
1979extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1980				struct kstat *stat);
1981extern void ext4_evict_inode(struct inode *);
1982extern void ext4_clear_inode(struct inode *);
1983extern int  ext4_sync_inode(handle_t *, struct inode *);
1984extern void ext4_dirty_inode(struct inode *, int);
1985extern int ext4_change_inode_journal_flag(struct inode *, int);
1986extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
 
1987extern int ext4_can_truncate(struct inode *inode);
1988extern void ext4_truncate(struct inode *);
1989extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
1990extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1991extern void ext4_set_inode_flags(struct inode *);
1992extern void ext4_get_inode_flags(struct ext4_inode_info *);
1993extern int ext4_alloc_da_blocks(struct inode *inode);
1994extern void ext4_set_aops(struct inode *inode);
1995extern int ext4_writepage_trans_blocks(struct inode *);
1996extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1997extern int ext4_discard_partial_page_buffers(handle_t *handle,
1998		struct address_space *mapping, loff_t from,
1999		loff_t length, int flags);
 
2000extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2001extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2002extern void ext4_da_update_reserve_space(struct inode *inode,
2003					int used, int quota_claim);
2004
2005/* indirect.c */
2006extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2007				struct ext4_map_blocks *map, int flags);
2008extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
2009				const struct iovec *iov, loff_t offset,
2010				unsigned long nr_segs);
2011extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2012extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk);
2013extern void ext4_ind_truncate(struct inode *inode);
 
 
2014
2015/* ioctl.c */
2016extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2017extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2018
2019/* migrate.c */
2020extern int ext4_ext_migrate(struct inode *);
 
2021
2022/* namei.c */
2023extern int ext4_dirent_csum_verify(struct inode *inode,
2024				   struct ext4_dir_entry *dirent);
2025extern int ext4_orphan_add(handle_t *, struct inode *);
2026extern int ext4_orphan_del(handle_t *, struct inode *);
2027extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2028				__u32 start_minor_hash, __u32 *next_hash);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2029
2030/* resize.c */
2031extern int ext4_group_add(struct super_block *sb,
2032				struct ext4_new_group_data *input);
2033extern int ext4_group_extend(struct super_block *sb,
2034				struct ext4_super_block *es,
2035				ext4_fsblk_t n_blocks_count);
2036extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2037
2038/* super.c */
2039extern int ext4_calculate_overhead(struct super_block *sb);
2040extern int ext4_superblock_csum_verify(struct super_block *sb,
2041				       struct ext4_super_block *es);
2042extern void ext4_superblock_csum_set(struct super_block *sb,
2043				     struct ext4_super_block *es);
2044extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2045extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2046extern void ext4_kvfree(void *ptr);
 
 
 
 
 
2047extern __printf(4, 5)
2048void __ext4_error(struct super_block *, const char *, unsigned int,
2049		  const char *, ...);
2050#define ext4_error(sb, message...)	__ext4_error(sb, __func__,	\
2051						     __LINE__, ## message)
2052extern __printf(5, 6)
2053void ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2054		      const char *, ...);
2055extern __printf(5, 6)
2056void ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2057		     const char *, ...);
2058extern void __ext4_std_error(struct super_block *, const char *,
2059			     unsigned int, int);
2060extern __printf(4, 5)
2061void __ext4_abort(struct super_block *, const char *, unsigned int,
2062		  const char *, ...);
2063#define ext4_abort(sb, message...)	__ext4_abort(sb, __func__, \
2064						       __LINE__, ## message)
2065extern __printf(4, 5)
2066void __ext4_warning(struct super_block *, const char *, unsigned int,
2067		    const char *, ...);
2068#define ext4_warning(sb, message...)	__ext4_warning(sb, __func__, \
2069						       __LINE__, ## message)
2070extern __printf(3, 4)
2071void ext4_msg(struct super_block *, const char *, const char *, ...);
2072extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2073			   const char *, unsigned int, const char *);
2074#define dump_mmp_msg(sb, mmp, msg)	__dump_mmp_msg(sb, mmp, __func__, \
2075						       __LINE__, msg)
2076extern __printf(7, 8)
2077void __ext4_grp_locked_error(const char *, unsigned int,
2078			     struct super_block *, ext4_group_t,
2079			     unsigned long, ext4_fsblk_t,
2080			     const char *, ...);
2081#define ext4_grp_locked_error(sb, grp, message...) \
2082	__ext4_grp_locked_error(__func__, __LINE__, (sb), (grp), ## message)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2083extern void ext4_update_dynamic_rev(struct super_block *sb);
2084extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2085					__u32 compat);
2086extern int ext4_update_rocompat_feature(handle_t *handle,
2087					struct super_block *sb,	__u32 rocompat);
2088extern int ext4_update_incompat_feature(handle_t *handle,
2089					struct super_block *sb,	__u32 incompat);
2090extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2091				      struct ext4_group_desc *bg);
2092extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2093				      struct ext4_group_desc *bg);
2094extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2095				     struct ext4_group_desc *bg);
2096extern __u32 ext4_free_group_clusters(struct super_block *sb,
2097				      struct ext4_group_desc *bg);
2098extern __u32 ext4_free_inodes_count(struct super_block *sb,
2099				 struct ext4_group_desc *bg);
2100extern __u32 ext4_used_dirs_count(struct super_block *sb,
2101				struct ext4_group_desc *bg);
2102extern __u32 ext4_itable_unused_count(struct super_block *sb,
2103				   struct ext4_group_desc *bg);
2104extern void ext4_block_bitmap_set(struct super_block *sb,
2105				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2106extern void ext4_inode_bitmap_set(struct super_block *sb,
2107				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2108extern void ext4_inode_table_set(struct super_block *sb,
2109				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2110extern void ext4_free_group_clusters_set(struct super_block *sb,
2111					 struct ext4_group_desc *bg,
2112					 __u32 count);
2113extern void ext4_free_inodes_set(struct super_block *sb,
2114				struct ext4_group_desc *bg, __u32 count);
2115extern void ext4_used_dirs_set(struct super_block *sb,
2116				struct ext4_group_desc *bg, __u32 count);
2117extern void ext4_itable_unused_set(struct super_block *sb,
2118				   struct ext4_group_desc *bg, __u32 count);
2119extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2120				       struct ext4_group_desc *gdp);
2121extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2122				     struct ext4_group_desc *gdp);
 
 
2123
2124static inline int ext4_has_group_desc_csum(struct super_block *sb)
2125{
2126	return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2127					  EXT4_FEATURE_RO_COMPAT_GDT_CSUM |
2128					  EXT4_FEATURE_RO_COMPAT_METADATA_CSUM);
2129}
2130
2131static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2132{
2133	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2134		le32_to_cpu(es->s_blocks_count_lo);
2135}
2136
2137static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2138{
2139	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2140		le32_to_cpu(es->s_r_blocks_count_lo);
2141}
2142
2143static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2144{
2145	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2146		le32_to_cpu(es->s_free_blocks_count_lo);
2147}
2148
2149static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2150					 ext4_fsblk_t blk)
2151{
2152	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2153	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2154}
2155
2156static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2157					      ext4_fsblk_t blk)
2158{
2159	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2160	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2161}
2162
2163static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2164					   ext4_fsblk_t blk)
2165{
2166	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2167	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2168}
2169
2170static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2171{
2172	if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2173		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2174			le32_to_cpu(raw_inode->i_size_lo);
2175	else
2176		return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2177}
2178
2179static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2180{
2181	raw_inode->i_size_lo = cpu_to_le32(i_size);
2182	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2183}
2184
2185static inline
2186struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2187					    ext4_group_t group)
2188{
2189	 struct ext4_group_info ***grp_info;
2190	 long indexv, indexh;
 
2191	 grp_info = EXT4_SB(sb)->s_group_info;
2192	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2193	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2194	 return grp_info[indexv][indexh];
2195}
2196
2197/*
2198 * Reading s_groups_count requires using smp_rmb() afterwards.  See
2199 * the locking protocol documented in the comments of ext4_group_add()
2200 * in resize.c
2201 */
2202static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2203{
2204	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2205
2206	smp_rmb();
2207	return ngroups;
2208}
2209
2210static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2211					     ext4_group_t block_group)
2212{
2213	return block_group >> sbi->s_log_groups_per_flex;
2214}
2215
2216static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2217{
2218	return 1 << sbi->s_log_groups_per_flex;
2219}
2220
2221#define ext4_std_error(sb, errno)				\
2222do {								\
2223	if ((errno))						\
2224		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2225} while (0)
2226
2227#ifdef CONFIG_SMP
2228/* Each CPU can accumulate percpu_counter_batch clusters in their local
2229 * counters. So we need to make sure we have free clusters more
2230 * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2231 */
2232#define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2233#else
2234#define EXT4_FREECLUSTERS_WATERMARK 0
2235#endif
2236
 
2237static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2238{
2239	/*
2240	 * XXX: replace with spinlock if seen contended -bzzz
2241	 */
2242	down_write(&EXT4_I(inode)->i_data_sem);
2243	if (newsize > EXT4_I(inode)->i_disksize)
2244		EXT4_I(inode)->i_disksize = newsize;
2245	up_write(&EXT4_I(inode)->i_data_sem);
2246	return ;
2247}
2248
2249struct ext4_group_info {
2250	unsigned long   bb_state;
2251	struct rb_root  bb_free_root;
2252	ext4_grpblk_t	bb_first_free;	/* first free block */
2253	ext4_grpblk_t	bb_free;	/* total free blocks */
2254	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2255	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2256	struct          list_head bb_prealloc_list;
2257#ifdef DOUBLE_CHECK
2258	void            *bb_bitmap;
2259#endif
2260	struct rw_semaphore alloc_sem;
2261	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2262					 * regions, index is order.
2263					 * bb_counters[3] = 5 means
2264					 * 5 free 8-block regions. */
2265};
2266
2267#define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2268#define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
 
 
2269
2270#define EXT4_MB_GRP_NEED_INIT(grp)	\
2271	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
 
 
 
 
2272
2273#define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2274	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2275#define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2276	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2277#define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2278	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2279
2280#define EXT4_MAX_CONTENTION		8
2281#define EXT4_CONTENTION_THRESHOLD	2
2282
2283static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2284					      ext4_group_t group)
2285{
2286	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2287}
2288
2289/*
2290 * Returns true if the filesystem is busy enough that attempts to
2291 * access the block group locks has run into contention.
2292 */
2293static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2294{
2295	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2296}
2297
2298static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2299{
2300	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2301	if (spin_trylock(lock))
2302		/*
2303		 * We're able to grab the lock right away, so drop the
2304		 * lock contention counter.
2305		 */
2306		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2307	else {
2308		/*
2309		 * The lock is busy, so bump the contention counter,
2310		 * and then wait on the spin lock.
2311		 */
2312		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2313				  EXT4_MAX_CONTENTION);
2314		spin_lock(lock);
2315	}
2316}
2317
2318static inline void ext4_unlock_group(struct super_block *sb,
2319					ext4_group_t group)
2320{
2321	spin_unlock(ext4_group_lock_ptr(sb, group));
2322}
2323
2324static inline void ext4_mark_super_dirty(struct super_block *sb)
2325{
2326	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
2327
2328	ext4_superblock_csum_set(sb, es);
2329	if (EXT4_SB(sb)->s_journal == NULL)
2330		sb->s_dirt =1;
2331}
2332
2333/*
2334 * Block validity checking
2335 */
2336#define ext4_check_indirect_blockref(inode, bh)				\
2337	ext4_check_blockref(__func__, __LINE__, inode,			\
2338			    (__le32 *)(bh)->b_data,			\
2339			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2340
2341#define ext4_ind_check_inode(inode)					\
2342	ext4_check_blockref(__func__, __LINE__, inode,			\
2343			    EXT4_I(inode)->i_data,			\
2344			    EXT4_NDIR_BLOCKS)
2345
2346/*
2347 * Inodes and files operations
2348 */
2349
2350/* dir.c */
2351extern const struct file_operations ext4_dir_operations;
2352
2353/* file.c */
2354extern const struct inode_operations ext4_file_inode_operations;
2355extern const struct file_operations ext4_file_operations;
2356extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2357
2358/* namei.c */
2359extern const struct inode_operations ext4_dir_inode_operations;
2360extern const struct inode_operations ext4_special_inode_operations;
2361extern struct dentry *ext4_get_parent(struct dentry *child);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2362
2363/* symlink.c */
2364extern const struct inode_operations ext4_symlink_inode_operations;
2365extern const struct inode_operations ext4_fast_symlink_inode_operations;
2366
2367/* block_validity */
2368extern void ext4_release_system_zone(struct super_block *sb);
2369extern int ext4_setup_system_zone(struct super_block *sb);
2370extern int __init ext4_init_system_zone(void);
2371extern void ext4_exit_system_zone(void);
2372extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2373				 ext4_fsblk_t start_blk,
2374				 unsigned int count);
2375extern int ext4_check_blockref(const char *, unsigned int,
2376			       struct inode *, __le32 *, unsigned int);
2377
2378/* extents.c */
 
 
 
 
 
 
 
 
 
2379extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2380extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2381extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
2382				       int chunk);
2383extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2384			       struct ext4_map_blocks *map, int flags);
2385extern void ext4_ext_truncate(struct inode *);
2386extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
2387				loff_t length);
2388extern void ext4_ext_init(struct super_block *);
2389extern void ext4_ext_release(struct super_block *);
2390extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2391			  loff_t len);
2392extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
2393			  ssize_t len);
2394extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2395			   struct ext4_map_blocks *map, int flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2396extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2397			__u64 start, __u64 len);
 
 
 
2398/* move_extent.c */
 
 
 
 
2399extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2400			     __u64 start_orig, __u64 start_donor,
2401			     __u64 len, __u64 *moved_len);
 
 
2402
2403/* page-io.c */
2404extern int __init ext4_init_pageio(void);
2405extern void ext4_exit_pageio(void);
2406extern void ext4_ioend_wait(struct inode *);
2407extern void ext4_free_io_end(ext4_io_end_t *io);
2408extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2409extern int ext4_end_io_nolock(ext4_io_end_t *io);
 
 
 
 
 
2410extern void ext4_io_submit(struct ext4_io_submit *io);
2411extern int ext4_bio_write_page(struct ext4_io_submit *io,
2412			       struct page *page,
2413			       int len,
2414			       struct writeback_control *wbc);
2415
2416/* mmp.c */
2417extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2418extern void ext4_mmp_csum_set(struct super_block *sb, struct mmp_struct *mmp);
2419extern int ext4_mmp_csum_verify(struct super_block *sb,
2420				struct mmp_struct *mmp);
2421
2422/* BH_Uninit flag: blocks are allocated but uninitialized on disk */
 
 
 
2423enum ext4_state_bits {
2424	BH_Uninit	/* blocks are allocated but uninitialized on disk */
2425	  = BH_JBDPrivateStart,
2426	BH_AllocFromCluster,	/* allocated blocks were part of already
2427				 * allocated cluster. Note that this flag will
2428				 * never, ever appear in a buffer_head's state
2429				 * flag. See EXT4_MAP_FROM_CLUSTER to see where
2430				 * this is used. */
2431	BH_Da_Mapped,	/* Delayed allocated block that now has a mapping. This
2432			 * flag is set when ext4_map_blocks is called on a
2433			 * delayed allocated block to get its real mapping. */
2434};
2435
2436BUFFER_FNS(Uninit, uninit)
2437TAS_BUFFER_FNS(Uninit, uninit)
2438BUFFER_FNS(Da_Mapped, da_mapped)
2439
2440/*
2441 * Add new method to test wether block and inode bitmaps are properly
2442 * initialized. With uninit_bg reading the block from disk is not enough
2443 * to mark the bitmap uptodate. We need to also zero-out the bitmap
2444 */
2445#define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2446
2447static inline int bitmap_uptodate(struct buffer_head *bh)
2448{
2449	return (buffer_uptodate(bh) &&
2450			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2451}
2452static inline void set_bitmap_uptodate(struct buffer_head *bh)
2453{
2454	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2455}
2456
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2457#define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
2458
2459/* For ioend & aio unwritten conversion wait queues */
2460#define EXT4_WQ_HASH_SZ		37
2461#define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2462					    EXT4_WQ_HASH_SZ])
2463#define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2464					     EXT4_WQ_HASH_SZ])
2465extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2466extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2467
2468#define EXT4_RESIZING	0
2469extern int ext4_resize_begin(struct super_block *sb);
2470extern void ext4_resize_end(struct super_block *sb);
2471
2472#endif	/* __KERNEL__ */
2473
2474#include "ext4_extents.h"
2475
2476#endif	/* _EXT4_H */
v3.15
   1/*
   2 *  ext4.h
   3 *
   4 * Copyright (C) 1992, 1993, 1994, 1995
   5 * Remy Card (card@masi.ibp.fr)
   6 * Laboratoire MASI - Institut Blaise Pascal
   7 * Universite Pierre et Marie Curie (Paris VI)
   8 *
   9 *  from
  10 *
  11 *  linux/include/linux/minix_fs.h
  12 *
  13 *  Copyright (C) 1991, 1992  Linus Torvalds
  14 */
  15
  16#ifndef _EXT4_H
  17#define _EXT4_H
  18
  19#include <linux/types.h>
  20#include <linux/blkdev.h>
  21#include <linux/magic.h>
  22#include <linux/jbd2.h>
  23#include <linux/quota.h>
  24#include <linux/rwsem.h>
  25#include <linux/rbtree.h>
  26#include <linux/seqlock.h>
  27#include <linux/mutex.h>
  28#include <linux/timer.h>
  29#include <linux/wait.h>
  30#include <linux/blockgroup_lock.h>
  31#include <linux/percpu_counter.h>
  32#include <linux/ratelimit.h>
  33#include <crypto/hash.h>
  34#include <linux/falloc.h>
  35#ifdef __KERNEL__
  36#include <linux/compat.h>
  37#endif
  38
  39/*
  40 * The fourth extended filesystem constants/structures
  41 */
  42
  43/*
  44 * Define EXT4FS_DEBUG to produce debug messages
  45 */
  46#undef EXT4FS_DEBUG
  47
  48/*
  49 * Debug code
  50 */
  51#ifdef EXT4FS_DEBUG
  52#define ext4_debug(f, a...)						\
  53	do {								\
  54		printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",	\
  55			__FILE__, __LINE__, __func__);			\
  56		printk(KERN_DEBUG f, ## a);				\
  57	} while (0)
  58#else
  59#define ext4_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
  60#endif
  61
  62/*
  63 * Turn on EXT_DEBUG to get lots of info about extents operations.
  64 */
  65#define EXT_DEBUG__
  66#ifdef EXT_DEBUG
  67#define ext_debug(fmt, ...)	printk(fmt, ##__VA_ARGS__)
  68#else
  69#define ext_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
  70#endif
  71
  72#define EXT4_ERROR_INODE(inode, fmt, a...) \
  73	ext4_error_inode((inode), __func__, __LINE__, 0, (fmt), ## a)
  74
  75#define EXT4_ERROR_INODE_BLOCK(inode, block, fmt, a...)			\
  76	ext4_error_inode((inode), __func__, __LINE__, (block), (fmt), ## a)
  77
  78#define EXT4_ERROR_FILE(file, block, fmt, a...)				\
  79	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
  80
  81/* data type for block offset of block group */
  82typedef int ext4_grpblk_t;
  83
  84/* data type for filesystem-wide blocks number */
  85typedef unsigned long long ext4_fsblk_t;
  86
  87/* data type for file logical block number */
  88typedef __u32 ext4_lblk_t;
  89
  90/* data type for block group number */
  91typedef unsigned int ext4_group_t;
  92
  93/*
  94 * Flags used in mballoc's allocation_context flags field.
  95 *
  96 * Also used to show what's going on for debugging purposes when the
  97 * flag field is exported via the traceport interface
  98 */
  99
 100/* prefer goal again. length */
 101#define EXT4_MB_HINT_MERGE		0x0001
 102/* blocks already reserved */
 103#define EXT4_MB_HINT_RESERVED		0x0002
 104/* metadata is being allocated */
 105#define EXT4_MB_HINT_METADATA		0x0004
 106/* first blocks in the file */
 107#define EXT4_MB_HINT_FIRST		0x0008
 108/* search for the best chunk */
 109#define EXT4_MB_HINT_BEST		0x0010
 110/* data is being allocated */
 111#define EXT4_MB_HINT_DATA		0x0020
 112/* don't preallocate (for tails) */
 113#define EXT4_MB_HINT_NOPREALLOC		0x0040
 114/* allocate for locality group */
 115#define EXT4_MB_HINT_GROUP_ALLOC	0x0080
 116/* allocate goal blocks or none */
 117#define EXT4_MB_HINT_GOAL_ONLY		0x0100
 118/* goal is meaningful */
 119#define EXT4_MB_HINT_TRY_GOAL		0x0200
 120/* blocks already pre-reserved by delayed allocation */
 121#define EXT4_MB_DELALLOC_RESERVED	0x0400
 122/* We are doing stream allocation */
 123#define EXT4_MB_STREAM_ALLOC		0x0800
 124/* Use reserved root blocks if needed */
 125#define EXT4_MB_USE_ROOT_BLOCKS		0x1000
 126/* Use blocks from reserved pool */
 127#define EXT4_MB_USE_RESERVED		0x2000
 128
 129struct ext4_allocation_request {
 130	/* target inode for block we're allocating */
 131	struct inode *inode;
 132	/* how many blocks we want to allocate */
 133	unsigned int len;
 134	/* logical block in target inode */
 135	ext4_lblk_t logical;
 136	/* the closest logical allocated block to the left */
 137	ext4_lblk_t lleft;
 138	/* the closest logical allocated block to the right */
 139	ext4_lblk_t lright;
 140	/* phys. target (a hint) */
 141	ext4_fsblk_t goal;
 142	/* phys. block for the closest logical allocated block to the left */
 143	ext4_fsblk_t pleft;
 144	/* phys. block for the closest logical allocated block to the right */
 145	ext4_fsblk_t pright;
 146	/* flags. see above EXT4_MB_HINT_* */
 147	unsigned int flags;
 148};
 149
 150/*
 151 * Logical to physical block mapping, used by ext4_map_blocks()
 152 *
 153 * This structure is used to pass requests into ext4_map_blocks() as
 154 * well as to store the information returned by ext4_map_blocks().  It
 155 * takes less room on the stack than a struct buffer_head.
 156 */
 157#define EXT4_MAP_NEW		(1 << BH_New)
 158#define EXT4_MAP_MAPPED		(1 << BH_Mapped)
 159#define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
 160#define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
 161#define EXT4_MAP_UNINIT		(1 << BH_Uninit)
 162/* Sometimes (in the bigalloc case, from ext4_da_get_block_prep) the caller of
 163 * ext4_map_blocks wants to know whether or not the underlying cluster has
 164 * already been accounted for. EXT4_MAP_FROM_CLUSTER conveys to the caller that
 165 * the requested mapping was from previously mapped (or delayed allocated)
 166 * cluster. We use BH_AllocFromCluster only for this flag. BH_AllocFromCluster
 167 * should never appear on buffer_head's state flags.
 168 */
 169#define EXT4_MAP_FROM_CLUSTER	(1 << BH_AllocFromCluster)
 170#define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 171				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
 172				 EXT4_MAP_UNINIT | EXT4_MAP_FROM_CLUSTER)
 173
 174struct ext4_map_blocks {
 175	ext4_fsblk_t m_pblk;
 176	ext4_lblk_t m_lblk;
 177	unsigned int m_len;
 178	unsigned int m_flags;
 179};
 180
 181/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 182 * Flags for ext4_io_end->flags
 183 */
 184#define	EXT4_IO_END_UNWRITTEN	0x0001
 
 
 
 
 
 
 
 
 
 
 
 185
 186/*
 187 * For converting uninitialized extents on a work queue. 'handle' is used for
 188 * buffered writeback.
 
 
 
 189 */
 190typedef struct ext4_io_end {
 191	struct list_head	list;		/* per-file finished IO list */
 192	handle_t		*handle;	/* handle reserved for extent
 193						 * conversion */
 194	struct inode		*inode;		/* file being written to */
 195	struct bio		*bio;		/* Linked list of completed
 196						 * bios covering the extent */
 197	unsigned int		flag;		/* unwritten or not */
 
 198	loff_t			offset;		/* offset in the file */
 199	ssize_t			size;		/* size of the extent */
 200	atomic_t		count;		/* reference counter */
 
 
 
 
 201} ext4_io_end_t;
 202
 203struct ext4_io_submit {
 204	int			io_op;
 205	struct bio		*io_bio;
 206	ext4_io_end_t		*io_end;
 
 207	sector_t		io_next_block;
 208};
 209
 210/*
 211 * Special inodes numbers
 212 */
 213#define	EXT4_BAD_INO		 1	/* Bad blocks inode */
 214#define EXT4_ROOT_INO		 2	/* Root inode */
 215#define EXT4_USR_QUOTA_INO	 3	/* User quota inode */
 216#define EXT4_GRP_QUOTA_INO	 4	/* Group quota inode */
 217#define EXT4_BOOT_LOADER_INO	 5	/* Boot loader inode */
 218#define EXT4_UNDEL_DIR_INO	 6	/* Undelete directory inode */
 219#define EXT4_RESIZE_INO		 7	/* Reserved group descriptors inode */
 220#define EXT4_JOURNAL_INO	 8	/* Journal inode */
 221
 222/* First non-reserved inode for old ext4 filesystems */
 223#define EXT4_GOOD_OLD_FIRST_INO	11
 224
 225/*
 226 * Maximal count of links to a file
 227 */
 228#define EXT4_LINK_MAX		65000
 229
 230/*
 231 * Macro-instructions used to manage several block sizes
 232 */
 233#define EXT4_MIN_BLOCK_SIZE		1024
 234#define	EXT4_MAX_BLOCK_SIZE		65536
 235#define EXT4_MIN_BLOCK_LOG_SIZE		10
 236#define EXT4_MAX_BLOCK_LOG_SIZE		16
 237#ifdef __KERNEL__
 238# define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
 239#else
 240# define EXT4_BLOCK_SIZE(s)		(EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 241#endif
 242#define	EXT4_ADDR_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 243#define EXT4_CLUSTER_SIZE(s)		(EXT4_BLOCK_SIZE(s) << \
 244					 EXT4_SB(s)->s_cluster_bits)
 245#ifdef __KERNEL__
 246# define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_blocksize_bits)
 247# define EXT4_CLUSTER_BITS(s)		(EXT4_SB(s)->s_cluster_bits)
 248#else
 249# define EXT4_BLOCK_SIZE_BITS(s)	((s)->s_log_block_size + 10)
 250#endif
 251#ifdef __KERNEL__
 252#define	EXT4_ADDR_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_addr_per_block_bits)
 253#define EXT4_INODE_SIZE(s)		(EXT4_SB(s)->s_inode_size)
 254#define EXT4_FIRST_INO(s)		(EXT4_SB(s)->s_first_ino)
 255#else
 256#define EXT4_INODE_SIZE(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 257				 EXT4_GOOD_OLD_INODE_SIZE : \
 258				 (s)->s_inode_size)
 259#define EXT4_FIRST_INO(s)	(((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 260				 EXT4_GOOD_OLD_FIRST_INO : \
 261				 (s)->s_first_ino)
 262#endif
 263#define EXT4_BLOCK_ALIGN(size, blkbits)		ALIGN((size), (1 << (blkbits)))
 264
 265/* Translate a block number to a cluster number */
 266#define EXT4_B2C(sbi, blk)	((blk) >> (sbi)->s_cluster_bits)
 267/* Translate a cluster number to a block number */
 268#define EXT4_C2B(sbi, cluster)	((cluster) << (sbi)->s_cluster_bits)
 269/* Translate # of blks to # of clusters */
 270#define EXT4_NUM_B2C(sbi, blks)	(((blks) + (sbi)->s_cluster_ratio - 1) >> \
 271				 (sbi)->s_cluster_bits)
 272/* Mask out the low bits to get the starting block of the cluster */
 273#define EXT4_PBLK_CMASK(s, pblk) ((pblk) &				\
 274				  ~((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
 275#define EXT4_LBLK_CMASK(s, lblk) ((lblk) &				\
 276				  ~((ext4_lblk_t) (s)->s_cluster_ratio - 1))
 277/* Get the cluster offset */
 278#define EXT4_PBLK_COFF(s, pblk) ((pblk) &				\
 279				 ((ext4_fsblk_t) (s)->s_cluster_ratio - 1))
 280#define EXT4_LBLK_COFF(s, lblk) ((lblk) &				\
 281				 ((ext4_lblk_t) (s)->s_cluster_ratio - 1))
 282
 283/*
 284 * Structure of a blocks group descriptor
 285 */
 286struct ext4_group_desc
 287{
 288	__le32	bg_block_bitmap_lo;	/* Blocks bitmap block */
 289	__le32	bg_inode_bitmap_lo;	/* Inodes bitmap block */
 290	__le32	bg_inode_table_lo;	/* Inodes table block */
 291	__le16	bg_free_blocks_count_lo;/* Free blocks count */
 292	__le16	bg_free_inodes_count_lo;/* Free inodes count */
 293	__le16	bg_used_dirs_count_lo;	/* Directories count */
 294	__le16	bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
 295	__le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
 296	__le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
 297	__le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
 298	__le16  bg_itable_unused_lo;	/* Unused inodes count */
 299	__le16  bg_checksum;		/* crc16(sb_uuid+group+desc) */
 300	__le32	bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
 301	__le32	bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
 302	__le32	bg_inode_table_hi;	/* Inodes table block MSB */
 303	__le16	bg_free_blocks_count_hi;/* Free blocks count MSB */
 304	__le16	bg_free_inodes_count_hi;/* Free inodes count MSB */
 305	__le16	bg_used_dirs_count_hi;	/* Directories count MSB */
 306	__le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 307	__le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
 308	__le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
 309	__le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
 310	__u32   bg_reserved;
 311};
 312
 313#define EXT4_BG_INODE_BITMAP_CSUM_HI_END	\
 314	(offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
 315	 sizeof(__le16))
 316#define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END	\
 317	(offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
 318	 sizeof(__le16))
 319
 320/*
 321 * Structure of a flex block group info
 322 */
 323
 324struct flex_groups {
 325	atomic64_t	free_clusters;
 326	atomic_t	free_inodes;
 327	atomic_t	used_dirs;
 328};
 329
 330#define EXT4_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not in use */
 331#define EXT4_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not in use */
 332#define EXT4_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
 333
 334/*
 335 * Macro-instructions used to manage group descriptors
 336 */
 337#define EXT4_MIN_DESC_SIZE		32
 338#define EXT4_MIN_DESC_SIZE_64BIT	64
 339#define	EXT4_MAX_DESC_SIZE		EXT4_MIN_BLOCK_SIZE
 340#define EXT4_DESC_SIZE(s)		(EXT4_SB(s)->s_desc_size)
 341#ifdef __KERNEL__
 342# define EXT4_BLOCKS_PER_GROUP(s)	(EXT4_SB(s)->s_blocks_per_group)
 343# define EXT4_CLUSTERS_PER_GROUP(s)	(EXT4_SB(s)->s_clusters_per_group)
 344# define EXT4_DESC_PER_BLOCK(s)		(EXT4_SB(s)->s_desc_per_block)
 345# define EXT4_INODES_PER_GROUP(s)	(EXT4_SB(s)->s_inodes_per_group)
 346# define EXT4_DESC_PER_BLOCK_BITS(s)	(EXT4_SB(s)->s_desc_per_block_bits)
 347#else
 348# define EXT4_BLOCKS_PER_GROUP(s)	((s)->s_blocks_per_group)
 349# define EXT4_DESC_PER_BLOCK(s)		(EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 350# define EXT4_INODES_PER_GROUP(s)	((s)->s_inodes_per_group)
 351#endif
 352
 353/*
 354 * Constants relative to the data blocks
 355 */
 356#define	EXT4_NDIR_BLOCKS		12
 357#define	EXT4_IND_BLOCK			EXT4_NDIR_BLOCKS
 358#define	EXT4_DIND_BLOCK			(EXT4_IND_BLOCK + 1)
 359#define	EXT4_TIND_BLOCK			(EXT4_DIND_BLOCK + 1)
 360#define	EXT4_N_BLOCKS			(EXT4_TIND_BLOCK + 1)
 361
 362/*
 363 * Inode flags
 364 */
 365#define	EXT4_SECRM_FL			0x00000001 /* Secure deletion */
 366#define	EXT4_UNRM_FL			0x00000002 /* Undelete */
 367#define	EXT4_COMPR_FL			0x00000004 /* Compress file */
 368#define EXT4_SYNC_FL			0x00000008 /* Synchronous updates */
 369#define EXT4_IMMUTABLE_FL		0x00000010 /* Immutable file */
 370#define EXT4_APPEND_FL			0x00000020 /* writes to file may only append */
 371#define EXT4_NODUMP_FL			0x00000040 /* do not dump file */
 372#define EXT4_NOATIME_FL			0x00000080 /* do not update atime */
 373/* Reserved for compression usage... */
 374#define EXT4_DIRTY_FL			0x00000100
 375#define EXT4_COMPRBLK_FL		0x00000200 /* One or more compressed clusters */
 376#define EXT4_NOCOMPR_FL			0x00000400 /* Don't compress */
 377#define EXT4_ECOMPR_FL			0x00000800 /* Compression error */
 378/* End compression flags --- maybe not all used */
 379#define EXT4_INDEX_FL			0x00001000 /* hash-indexed directory */
 380#define EXT4_IMAGIC_FL			0x00002000 /* AFS directory */
 381#define EXT4_JOURNAL_DATA_FL		0x00004000 /* file data should be journaled */
 382#define EXT4_NOTAIL_FL			0x00008000 /* file tail should not be merged */
 383#define EXT4_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
 384#define EXT4_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
 385#define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 386#define EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
 387#define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
 388#define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
 389#define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
 390#define EXT4_RESERVED_FL		0x80000000 /* reserved for ext4 lib */
 391
 392#define EXT4_FL_USER_VISIBLE		0x004BDFFF /* User visible flags */
 393#define EXT4_FL_USER_MODIFIABLE		0x004380FF /* User modifiable flags */
 394
 395/* Flags that should be inherited by new inodes from their parent. */
 396#define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 397			   EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 398			   EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 399			   EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 400
 401/* Flags that are appropriate for regular files (all but dir-specific ones). */
 402#define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 403
 404/* Flags that are appropriate for non-directories/regular files. */
 405#define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 406
 407/* Mask out flags that are inappropriate for the given type of inode. */
 408static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 409{
 410	if (S_ISDIR(mode))
 411		return flags;
 412	else if (S_ISREG(mode))
 413		return flags & EXT4_REG_FLMASK;
 414	else
 415		return flags & EXT4_OTHER_FLMASK;
 416}
 417
 418/*
 419 * Inode flags used for atomic set/get
 420 */
 421enum {
 422	EXT4_INODE_SECRM	= 0,	/* Secure deletion */
 423	EXT4_INODE_UNRM		= 1,	/* Undelete */
 424	EXT4_INODE_COMPR	= 2,	/* Compress file */
 425	EXT4_INODE_SYNC		= 3,	/* Synchronous updates */
 426	EXT4_INODE_IMMUTABLE	= 4,	/* Immutable file */
 427	EXT4_INODE_APPEND	= 5,	/* writes to file may only append */
 428	EXT4_INODE_NODUMP	= 6,	/* do not dump file */
 429	EXT4_INODE_NOATIME	= 7,	/* do not update atime */
 430/* Reserved for compression usage... */
 431	EXT4_INODE_DIRTY	= 8,
 432	EXT4_INODE_COMPRBLK	= 9,	/* One or more compressed clusters */
 433	EXT4_INODE_NOCOMPR	= 10,	/* Don't compress */
 434	EXT4_INODE_ECOMPR	= 11,	/* Compression error */
 435/* End compression flags --- maybe not all used */
 436	EXT4_INODE_INDEX	= 12,	/* hash-indexed directory */
 437	EXT4_INODE_IMAGIC	= 13,	/* AFS directory */
 438	EXT4_INODE_JOURNAL_DATA	= 14,	/* file data should be journaled */
 439	EXT4_INODE_NOTAIL	= 15,	/* file tail should not be merged */
 440	EXT4_INODE_DIRSYNC	= 16,	/* dirsync behaviour (directories only) */
 441	EXT4_INODE_TOPDIR	= 17,	/* Top of directory hierarchies*/
 442	EXT4_INODE_HUGE_FILE	= 18,	/* Set to each huge file */
 443	EXT4_INODE_EXTENTS	= 19,	/* Inode uses extents */
 444	EXT4_INODE_EA_INODE	= 21,	/* Inode used for large EA */
 445	EXT4_INODE_EOFBLOCKS	= 22,	/* Blocks allocated beyond EOF */
 446	EXT4_INODE_INLINE_DATA	= 28,	/* Data in inode. */
 447	EXT4_INODE_RESERVED	= 31,	/* reserved for ext4 lib */
 448};
 449
 
 
 
 
 
 450/*
 451 * Since it's pretty easy to mix up bit numbers and hex values, we use a
 452 * build-time check to make sure that EXT4_XXX_FL is consistent with respect to
 453 * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost
 454 * any extra space in the compiled kernel image, otherwise, the build will fail.
 455 * It's important that these values are the same, since we are using
 456 * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent
 457 * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk
 458 * values found in ext2, ext3 and ext4 filesystems, and of course the values
 459 * defined in e2fsprogs.
 
 460 *
 461 * It's not paranoia if the Murphy's Law really *is* out to get you.  :-)
 462 */
 463#define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG))
 464#define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG))
 465
 466static inline void ext4_check_flag_values(void)
 467{
 468	CHECK_FLAG_VALUE(SECRM);
 469	CHECK_FLAG_VALUE(UNRM);
 470	CHECK_FLAG_VALUE(COMPR);
 471	CHECK_FLAG_VALUE(SYNC);
 472	CHECK_FLAG_VALUE(IMMUTABLE);
 473	CHECK_FLAG_VALUE(APPEND);
 474	CHECK_FLAG_VALUE(NODUMP);
 475	CHECK_FLAG_VALUE(NOATIME);
 476	CHECK_FLAG_VALUE(DIRTY);
 477	CHECK_FLAG_VALUE(COMPRBLK);
 478	CHECK_FLAG_VALUE(NOCOMPR);
 479	CHECK_FLAG_VALUE(ECOMPR);
 480	CHECK_FLAG_VALUE(INDEX);
 481	CHECK_FLAG_VALUE(IMAGIC);
 482	CHECK_FLAG_VALUE(JOURNAL_DATA);
 483	CHECK_FLAG_VALUE(NOTAIL);
 484	CHECK_FLAG_VALUE(DIRSYNC);
 485	CHECK_FLAG_VALUE(TOPDIR);
 486	CHECK_FLAG_VALUE(HUGE_FILE);
 487	CHECK_FLAG_VALUE(EXTENTS);
 488	CHECK_FLAG_VALUE(EA_INODE);
 489	CHECK_FLAG_VALUE(EOFBLOCKS);
 490	CHECK_FLAG_VALUE(INLINE_DATA);
 491	CHECK_FLAG_VALUE(RESERVED);
 492}
 493
 494/* Used to pass group descriptor data when online resize is done */
 495struct ext4_new_group_input {
 496	__u32 group;		/* Group number for this data */
 497	__u64 block_bitmap;	/* Absolute block number of block bitmap */
 498	__u64 inode_bitmap;	/* Absolute block number of inode bitmap */
 499	__u64 inode_table;	/* Absolute block number of inode table start */
 500	__u32 blocks_count;	/* Total number of blocks in this group */
 501	__u16 reserved_blocks;	/* Number of reserved blocks in this group */
 502	__u16 unused;
 503};
 504
 505#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 506struct compat_ext4_new_group_input {
 507	u32 group;
 508	compat_u64 block_bitmap;
 509	compat_u64 inode_bitmap;
 510	compat_u64 inode_table;
 511	u32 blocks_count;
 512	u16 reserved_blocks;
 513	u16 unused;
 514};
 515#endif
 516
 517/* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 518struct ext4_new_group_data {
 519	__u32 group;
 520	__u64 block_bitmap;
 521	__u64 inode_bitmap;
 522	__u64 inode_table;
 523	__u32 blocks_count;
 524	__u16 reserved_blocks;
 525	__u16 unused;
 526	__u32 free_blocks_count;
 527};
 528
 529/* Indexes used to index group tables in ext4_new_group_data */
 530enum {
 531	BLOCK_BITMAP = 0,	/* block bitmap */
 532	INODE_BITMAP,		/* inode bitmap */
 533	INODE_TABLE,		/* inode tables */
 534	GROUP_TABLE_COUNT,
 535};
 536
 537/*
 538 * Flags used by ext4_map_blocks()
 539 */
 540	/* Allocate any needed blocks and/or convert an unitialized
 541	   extent to be an initialized ext4 */
 542#define EXT4_GET_BLOCKS_CREATE			0x0001
 543	/* Request the creation of an unitialized extent */
 544#define EXT4_GET_BLOCKS_UNINIT_EXT		0x0002
 545#define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT	(EXT4_GET_BLOCKS_UNINIT_EXT|\
 546						 EXT4_GET_BLOCKS_CREATE)
 547	/* Caller is from the delayed allocation writeout path
 548	 * finally doing the actual allocation of delayed blocks */
 
 549#define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
 550	/* caller is from the direct IO path, request to creation of an
 551	unitialized extents if not allocated, split the uninitialized
 552	extent if blocks has been preallocated already*/
 553#define EXT4_GET_BLOCKS_PRE_IO			0x0008
 554#define EXT4_GET_BLOCKS_CONVERT			0x0010
 555#define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
 556					 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 557	/* Convert extent to initialized after IO complete */
 558#define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
 559					 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 560	/* Eventual metadata allocation (due to growing extent tree)
 561	 * should not fail, so try to use reserved blocks for that.*/
 562#define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
 563	/* Don't normalize allocation size (used for fallocate) */
 564#define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
 565	/* Request will not result in inode size update (user for fallocate) */
 566#define EXT4_GET_BLOCKS_KEEP_SIZE		0x0080
 567	/* Do not take i_data_sem locking in ext4_map_blocks */
 568#define EXT4_GET_BLOCKS_NO_LOCK			0x0100
 569	/* Do not put hole in extent cache */
 570#define EXT4_GET_BLOCKS_NO_PUT_HOLE		0x0200
 571	/* Convert written extents to unwritten */
 572#define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0400
 573
 574/*
 575 * The bit position of these flags must not overlap with any of the
 576 * EXT4_GET_BLOCKS_*.  They are used by ext4_ext_find_extent(),
 577 * read_extent_tree_block(), ext4_split_extent_at(),
 578 * ext4_ext_insert_extent(), and ext4_ext_create_new_leaf().
 579 * EXT4_EX_NOCACHE is used to indicate that the we shouldn't be
 580 * caching the extents when reading from the extent tree while a
 581 * truncate or punch hole operation is in progress.
 582 */
 583#define EXT4_EX_NOCACHE				0x0400
 584#define EXT4_EX_FORCE_CACHE			0x0800
 585
 586/*
 587 * Flags used by ext4_free_blocks
 588 */
 589#define EXT4_FREE_BLOCKS_METADATA	0x0001
 590#define EXT4_FREE_BLOCKS_FORGET		0x0002
 591#define EXT4_FREE_BLOCKS_VALIDATED	0x0004
 592#define EXT4_FREE_BLOCKS_NO_QUOT_UPDATE	0x0008
 593#define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
 594#define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
 595#define EXT4_FREE_BLOCKS_RESERVE		0x0040
 
 
 
 
 596
 597/*
 598 * ioctl commands
 599 */
 600#define	EXT4_IOC_GETFLAGS		FS_IOC_GETFLAGS
 601#define	EXT4_IOC_SETFLAGS		FS_IOC_SETFLAGS
 602#define	EXT4_IOC_GETVERSION		_IOR('f', 3, long)
 603#define	EXT4_IOC_SETVERSION		_IOW('f', 4, long)
 604#define	EXT4_IOC_GETVERSION_OLD		FS_IOC_GETVERSION
 605#define	EXT4_IOC_SETVERSION_OLD		FS_IOC_SETVERSION
 606#define EXT4_IOC_GETRSVSZ		_IOR('f', 5, long)
 607#define EXT4_IOC_SETRSVSZ		_IOW('f', 6, long)
 608#define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
 609#define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
 610#define EXT4_IOC_MIGRATE		_IO('f', 9)
 611 /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 612 /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 613#define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
 614#define EXT4_IOC_MOVE_EXT		_IOWR('f', 15, struct move_extent)
 615#define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
 616#define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
 617#define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
 618
 619#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 620/*
 621 * ioctl commands in 32 bit emulation
 622 */
 623#define EXT4_IOC32_GETFLAGS		FS_IOC32_GETFLAGS
 624#define EXT4_IOC32_SETFLAGS		FS_IOC32_SETFLAGS
 625#define EXT4_IOC32_GETVERSION		_IOR('f', 3, int)
 626#define EXT4_IOC32_SETVERSION		_IOW('f', 4, int)
 627#define EXT4_IOC32_GETRSVSZ		_IOR('f', 5, int)
 628#define EXT4_IOC32_SETRSVSZ		_IOW('f', 6, int)
 629#define EXT4_IOC32_GROUP_EXTEND		_IOW('f', 7, unsigned int)
 630#define EXT4_IOC32_GROUP_ADD		_IOW('f', 8, struct compat_ext4_new_group_input)
 631#define EXT4_IOC32_GETVERSION_OLD	FS_IOC32_GETVERSION
 632#define EXT4_IOC32_SETVERSION_OLD	FS_IOC32_SETVERSION
 633#endif
 634
 635/* Max physical block we can address w/o extents */
 636#define EXT4_MAX_BLOCK_FILE_PHYS	0xFFFFFFFF
 637
 638/*
 639 * Structure of an inode on the disk
 640 */
 641struct ext4_inode {
 642	__le16	i_mode;		/* File mode */
 643	__le16	i_uid;		/* Low 16 bits of Owner Uid */
 644	__le32	i_size_lo;	/* Size in bytes */
 645	__le32	i_atime;	/* Access time */
 646	__le32	i_ctime;	/* Inode Change time */
 647	__le32	i_mtime;	/* Modification time */
 648	__le32	i_dtime;	/* Deletion Time */
 649	__le16	i_gid;		/* Low 16 bits of Group Id */
 650	__le16	i_links_count;	/* Links count */
 651	__le32	i_blocks_lo;	/* Blocks count */
 652	__le32	i_flags;	/* File flags */
 653	union {
 654		struct {
 655			__le32  l_i_version;
 656		} linux1;
 657		struct {
 658			__u32  h_i_translator;
 659		} hurd1;
 660		struct {
 661			__u32  m_i_reserved1;
 662		} masix1;
 663	} osd1;				/* OS dependent 1 */
 664	__le32	i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 665	__le32	i_generation;	/* File version (for NFS) */
 666	__le32	i_file_acl_lo;	/* File ACL */
 667	__le32	i_size_high;
 668	__le32	i_obso_faddr;	/* Obsoleted fragment address */
 669	union {
 670		struct {
 671			__le16	l_i_blocks_high; /* were l_i_reserved1 */
 672			__le16	l_i_file_acl_high;
 673			__le16	l_i_uid_high;	/* these 2 fields */
 674			__le16	l_i_gid_high;	/* were reserved2[0] */
 675			__le16	l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
 676			__le16	l_i_reserved;
 677		} linux2;
 678		struct {
 679			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
 680			__u16	h_i_mode_high;
 681			__u16	h_i_uid_high;
 682			__u16	h_i_gid_high;
 683			__u32	h_i_author;
 684		} hurd2;
 685		struct {
 686			__le16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
 687			__le16	m_i_file_acl_high;
 688			__u32	m_i_reserved2[2];
 689		} masix2;
 690	} osd2;				/* OS dependent 2 */
 691	__le16	i_extra_isize;
 692	__le16	i_checksum_hi;	/* crc32c(uuid+inum+inode) BE */
 693	__le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 694	__le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 695	__le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 696	__le32  i_crtime;       /* File Creation time */
 697	__le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 698	__le32  i_version_hi;	/* high 32 bits for 64-bit version */
 699};
 700
 701struct move_extent {
 702	__u32 reserved;		/* should be zero */
 703	__u32 donor_fd;		/* donor file descriptor */
 704	__u64 orig_start;	/* logical start offset in block for orig */
 705	__u64 donor_start;	/* logical start offset in block for donor */
 706	__u64 len;		/* block length to be moved */
 707	__u64 moved_len;	/* moved block length */
 708};
 709
 710#define EXT4_EPOCH_BITS 2
 711#define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 712#define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 713
 714/*
 715 * Extended fields will fit into an inode if the filesystem was formatted
 716 * with large inodes (-I 256 or larger) and there are not currently any EAs
 717 * consuming all of the available space. For new inodes we always reserve
 718 * enough space for the kernel's known extended fields, but for inodes
 719 * created with an old kernel this might not have been the case. None of
 720 * the extended inode fields is critical for correct filesystem operation.
 721 * This macro checks if a certain field fits in the inode. Note that
 722 * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 723 */
 724#define EXT4_FITS_IN_INODE(ext4_inode, einode, field)	\
 725	((offsetof(typeof(*ext4_inode), field) +	\
 726	  sizeof((ext4_inode)->field))			\
 727	<= (EXT4_GOOD_OLD_INODE_SIZE +			\
 728	    (einode)->i_extra_isize))			\
 729
 730static inline __le32 ext4_encode_extra_time(struct timespec *time)
 731{
 732       return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 733			   (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
 734                          ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 735}
 736
 737static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 738{
 739       if (sizeof(time->tv_sec) > 4)
 740	       time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 741			       << 32;
 742       time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 743}
 744
 745#define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)			       \
 746do {									       \
 747	(raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);	       \
 748	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 749		(raw_inode)->xtime ## _extra =				       \
 750				ext4_encode_extra_time(&(inode)->xtime);       \
 751} while (0)
 752
 753#define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)			       \
 754do {									       \
 755	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
 756		(raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 757	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
 758		(raw_inode)->xtime ## _extra =				       \
 759				ext4_encode_extra_time(&(einode)->xtime);      \
 760} while (0)
 761
 762#define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)			       \
 763do {									       \
 764	(inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 765	if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 766		ext4_decode_extra_time(&(inode)->xtime,			       \
 767				       raw_inode->xtime ## _extra);	       \
 768	else								       \
 769		(inode)->xtime.tv_nsec = 0;				       \
 770} while (0)
 771
 772#define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)			       \
 773do {									       \
 774	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))		       \
 775		(einode)->xtime.tv_sec = 				       \
 776			(signed)le32_to_cpu((raw_inode)->xtime);	       \
 777	else								       \
 778		(einode)->xtime.tv_sec = 0;				       \
 779	if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))	       \
 780		ext4_decode_extra_time(&(einode)->xtime,		       \
 781				       raw_inode->xtime ## _extra);	       \
 782	else								       \
 783		(einode)->xtime.tv_nsec = 0;				       \
 784} while (0)
 785
 786#define i_disk_version osd1.linux1.l_i_version
 787
 788#if defined(__KERNEL__) || defined(__linux__)
 789#define i_reserved1	osd1.linux1.l_i_reserved1
 790#define i_file_acl_high	osd2.linux2.l_i_file_acl_high
 791#define i_blocks_high	osd2.linux2.l_i_blocks_high
 792#define i_uid_low	i_uid
 793#define i_gid_low	i_gid
 794#define i_uid_high	osd2.linux2.l_i_uid_high
 795#define i_gid_high	osd2.linux2.l_i_gid_high
 796#define i_checksum_lo	osd2.linux2.l_i_checksum_lo
 797
 798#elif defined(__GNU__)
 799
 800#define i_translator	osd1.hurd1.h_i_translator
 801#define i_uid_high	osd2.hurd2.h_i_uid_high
 802#define i_gid_high	osd2.hurd2.h_i_gid_high
 803#define i_author	osd2.hurd2.h_i_author
 804
 805#elif defined(__masix__)
 806
 807#define i_reserved1	osd1.masix1.m_i_reserved1
 808#define i_file_acl_high	osd2.masix2.m_i_file_acl_high
 809#define i_reserved2	osd2.masix2.m_i_reserved2
 810
 811#endif /* defined(__KERNEL__) || defined(__linux__) */
 812
 813#include "extents_status.h"
 
 
 
 
 
 
 
 
 
 814
 815/*
 816 * fourth extended file system inode data in memory
 817 */
 818struct ext4_inode_info {
 819	__le32	i_data[15];	/* unconverted */
 820	__u32	i_dtime;
 821	ext4_fsblk_t	i_file_acl;
 822
 823	/*
 824	 * i_block_group is the number of the block group which contains
 825	 * this file's inode.  Constant across the lifetime of the inode,
 826	 * it is ued for making block allocation decisions - we try to
 827	 * place a file's data blocks near its inode block, and new inodes
 828	 * near to their parent directory's inode.
 829	 */
 830	ext4_group_t	i_block_group;
 831	ext4_lblk_t	i_dir_start_lookup;
 832#if (BITS_PER_LONG < 64)
 833	unsigned long	i_state_flags;		/* Dynamic state flags */
 834#endif
 835	unsigned long	i_flags;
 836
 
 837	/*
 838	 * Extended attributes can be read independently of the main file
 839	 * data. Taking i_mutex even when reading would cause contention
 840	 * between readers of EAs and writers of regular file data, so
 841	 * instead we synchronize on xattr_sem when reading or changing
 842	 * EAs.
 843	 */
 844	struct rw_semaphore xattr_sem;
 
 845
 846	struct list_head i_orphan;	/* unlinked but open inodes */
 847
 848	/*
 849	 * i_disksize keeps track of what the inode size is ON DISK, not
 850	 * in memory.  During truncate, i_size is set to the new size by
 851	 * the VFS prior to calling ext4_truncate(), but the filesystem won't
 852	 * set i_disksize to 0 until the truncate is actually under way.
 853	 *
 854	 * The intent is that i_disksize always represents the blocks which
 855	 * are used by this file.  This allows recovery to restart truncate
 856	 * on orphans if we crash during truncate.  We actually write i_disksize
 857	 * into the on-disk inode when writing inodes out, instead of i_size.
 858	 *
 859	 * The only time when i_disksize and i_size may be different is when
 860	 * a truncate is in progress.  The only things which change i_disksize
 861	 * are ext4_get_block (growth) and ext4_truncate (shrinkth).
 862	 */
 863	loff_t	i_disksize;
 864
 865	/*
 866	 * i_data_sem is for serialising ext4_truncate() against
 867	 * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
 868	 * data tree are chopped off during truncate. We can't do that in
 869	 * ext4 because whenever we perform intermediate commits during
 870	 * truncate, the inode and all the metadata blocks *must* be in a
 871	 * consistent state which allows truncation of the orphans to restart
 872	 * during recovery.  Hence we must fix the get_block-vs-truncate race
 873	 * by other means, so we have i_data_sem.
 874	 */
 875	struct rw_semaphore i_data_sem;
 876	struct inode vfs_inode;
 877	struct jbd2_inode *jinode;
 878
 
 879	/*
 880	 * File creation time. Its function is same as that of
 881	 * struct timespec i_{a,c,m}time in the generic inode.
 882	 */
 883	struct timespec i_crtime;
 884
 885	/* mballoc */
 886	struct list_head i_prealloc_list;
 887	spinlock_t i_prealloc_lock;
 888
 889	/* extents status tree */
 890	struct ext4_es_tree i_es_tree;
 891	rwlock_t i_es_lock;
 892	struct list_head i_es_lru;
 893	unsigned int i_es_lru_nr;	/* protected by i_es_lock */
 894	unsigned long i_touch_when;	/* jiffies of last accessing */
 895
 896	/* ialloc */
 897	ext4_group_t	i_last_alloc_group;
 898
 899	/* allocation reservation info for delalloc */
 900	/* In case of bigalloc, these refer to clusters rather than blocks */
 901	unsigned int i_reserved_data_blocks;
 902	unsigned int i_reserved_meta_blocks;
 903	unsigned int i_allocated_meta_blocks;
 904	ext4_lblk_t i_da_metadata_calc_last_lblock;
 905	int i_da_metadata_calc_len;
 906
 907	/* on-disk additional length */
 908	__u16 i_extra_isize;
 909
 910	/* Indicate the inline data space. */
 911	u16 i_inline_off;
 912	u16 i_inline_size;
 913
 914#ifdef CONFIG_QUOTA
 915	/* quota space reservation, managed internally by quota code */
 916	qsize_t i_reserved_quota;
 917#endif
 918
 919	/* Lock protecting lists below */
 
 920	spinlock_t i_completed_io_lock;
 921	/*
 922	 * Completed IOs that need unwritten extents handling and have
 923	 * transaction reserved
 924	 */
 925	struct list_head i_rsv_conversion_list;
 926	/*
 927	 * Completed IOs that need unwritten extents handling and don't have
 928	 * transaction reserved
 929	 */
 930	atomic_t i_ioend_count;	/* Number of outstanding io_end structs */
 931	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
 932	struct work_struct i_rsv_conversion_work;
 
 933
 934	spinlock_t i_block_reservation_lock;
 935
 936	/*
 937	 * Transactions that contain inode's metadata needed to complete
 938	 * fsync and fdatasync, respectively.
 939	 */
 940	tid_t i_sync_tid;
 941	tid_t i_datasync_tid;
 942
 943	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
 944	__u32 i_csum_seed;
 945};
 946
 947/*
 948 * File system states
 949 */
 950#define	EXT4_VALID_FS			0x0001	/* Unmounted cleanly */
 951#define	EXT4_ERROR_FS			0x0002	/* Errors detected */
 952#define	EXT4_ORPHAN_FS			0x0004	/* Orphans being recovered */
 953
 954/*
 955 * Misc. filesystem flags
 956 */
 957#define EXT2_FLAGS_SIGNED_HASH		0x0001  /* Signed dirhash in use */
 958#define EXT2_FLAGS_UNSIGNED_HASH	0x0002  /* Unsigned dirhash in use */
 959#define EXT2_FLAGS_TEST_FILESYS		0x0004	/* to test development code */
 960
 961/*
 962 * Mount flags set via mount options or defaults
 963 */
 964#define EXT4_MOUNT_GRPID		0x00004	/* Create files with directory's group */
 965#define EXT4_MOUNT_DEBUG		0x00008	/* Some debugging messages */
 966#define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
 967#define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
 968#define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
 969#define EXT4_MOUNT_ERRORS_MASK		0x00070
 970#define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
 971#define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
 972#define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */
 973#define EXT4_MOUNT_JOURNAL_DATA		0x00400	/* Write data to journal */
 974#define EXT4_MOUNT_ORDERED_DATA		0x00800	/* Flush data before commit */
 975#define EXT4_MOUNT_WRITEBACK_DATA	0x00C00	/* No data ordering */
 976#define EXT4_MOUNT_UPDATE_JOURNAL	0x01000	/* Update the journal format */
 977#define EXT4_MOUNT_NO_UID32		0x02000  /* Disable 32-bit UIDs */
 978#define EXT4_MOUNT_XATTR_USER		0x04000	/* Extended user attributes */
 979#define EXT4_MOUNT_POSIX_ACL		0x08000	/* POSIX Access Control Lists */
 980#define EXT4_MOUNT_NO_AUTO_DA_ALLOC	0x10000	/* No auto delalloc mapping */
 981#define EXT4_MOUNT_BARRIER		0x20000 /* Use block barriers */
 982#define EXT4_MOUNT_QUOTA		0x80000 /* Some quota option set */
 983#define EXT4_MOUNT_USRQUOTA		0x100000 /* "old" user quota */
 984#define EXT4_MOUNT_GRPQUOTA		0x200000 /* "old" group quota */
 985#define EXT4_MOUNT_DIOREAD_NOLOCK	0x400000 /* Enable support for dio read nolocking */
 986#define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
 987#define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
 
 988#define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
 989#define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
 990#define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
 991#define EXT4_MOUNT_DISCARD		0x40000000 /* Issue DISCARD requests */
 992#define EXT4_MOUNT_INIT_INODE_TABLE	0x80000000 /* Initialize uninitialized itables */
 993
 994/*
 995 * Mount flags set either automatically (could not be set by mount option)
 996 * based on per file system feature or property or in special cases such as
 997 * distinguishing between explicit mount option definition and default.
 998 */
 999#define EXT4_MOUNT2_EXPLICIT_DELALLOC	0x00000001 /* User explicitly
1000						      specified delalloc */
1001#define EXT4_MOUNT2_STD_GROUP_SIZE	0x00000002 /* We have standard group
1002						      size of blocksize * 8
1003						      blocks */
1004#define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated
1005						      file systems */
1006
1007#define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
1008						~EXT4_MOUNT_##opt
1009#define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
1010						EXT4_MOUNT_##opt
1011#define test_opt(sb, opt)		(EXT4_SB(sb)->s_mount_opt & \
1012					 EXT4_MOUNT_##opt)
1013
1014#define clear_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 &= \
1015						~EXT4_MOUNT2_##opt
1016#define set_opt2(sb, opt)		EXT4_SB(sb)->s_mount_opt2 |= \
1017						EXT4_MOUNT2_##opt
1018#define test_opt2(sb, opt)		(EXT4_SB(sb)->s_mount_opt2 & \
1019					 EXT4_MOUNT2_##opt)
1020
1021#define ext4_test_and_set_bit		__test_and_set_bit_le
1022#define ext4_set_bit			__set_bit_le
1023#define ext4_set_bit_atomic		ext2_set_bit_atomic
1024#define ext4_test_and_clear_bit		__test_and_clear_bit_le
1025#define ext4_clear_bit			__clear_bit_le
1026#define ext4_clear_bit_atomic		ext2_clear_bit_atomic
1027#define ext4_test_bit			test_bit_le
1028#define ext4_find_next_zero_bit		find_next_zero_bit_le
1029#define ext4_find_next_bit		find_next_bit_le
1030
1031extern void ext4_set_bits(void *bm, int cur, int len);
1032
1033/*
1034 * Maximal mount counts between two filesystem checks
1035 */
1036#define EXT4_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
1037#define EXT4_DFL_CHECKINTERVAL		0	/* Don't use interval check */
1038
1039/*
1040 * Behaviour when detecting errors
1041 */
1042#define EXT4_ERRORS_CONTINUE		1	/* Continue execution */
1043#define EXT4_ERRORS_RO			2	/* Remount fs read-only */
1044#define EXT4_ERRORS_PANIC		3	/* Panic */
1045#define EXT4_ERRORS_DEFAULT		EXT4_ERRORS_CONTINUE
1046
1047/* Metadata checksum algorithm codes */
1048#define EXT4_CRC32C_CHKSUM		1
1049
1050/*
1051 * Structure of the super block
1052 */
1053struct ext4_super_block {
1054/*00*/	__le32	s_inodes_count;		/* Inodes count */
1055	__le32	s_blocks_count_lo;	/* Blocks count */
1056	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
1057	__le32	s_free_blocks_count_lo;	/* Free blocks count */
1058/*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
1059	__le32	s_first_data_block;	/* First Data Block */
1060	__le32	s_log_block_size;	/* Block size */
1061	__le32	s_log_cluster_size;	/* Allocation cluster size */
1062/*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
1063	__le32	s_clusters_per_group;	/* # Clusters per group */
1064	__le32	s_inodes_per_group;	/* # Inodes per group */
1065	__le32	s_mtime;		/* Mount time */
1066/*30*/	__le32	s_wtime;		/* Write time */
1067	__le16	s_mnt_count;		/* Mount count */
1068	__le16	s_max_mnt_count;	/* Maximal mount count */
1069	__le16	s_magic;		/* Magic signature */
1070	__le16	s_state;		/* File system state */
1071	__le16	s_errors;		/* Behaviour when detecting errors */
1072	__le16	s_minor_rev_level;	/* minor revision level */
1073/*40*/	__le32	s_lastcheck;		/* time of last check */
1074	__le32	s_checkinterval;	/* max. time between checks */
1075	__le32	s_creator_os;		/* OS */
1076	__le32	s_rev_level;		/* Revision level */
1077/*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
1078	__le16	s_def_resgid;		/* Default gid for reserved blocks */
1079	/*
1080	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
1081	 *
1082	 * Note: the difference between the compatible feature set and
1083	 * the incompatible feature set is that if there is a bit set
1084	 * in the incompatible feature set that the kernel doesn't
1085	 * know about, it should refuse to mount the filesystem.
1086	 *
1087	 * e2fsck's requirements are more strict; if it doesn't know
1088	 * about a feature in either the compatible or incompatible
1089	 * feature set, it must abort and not try to meddle with
1090	 * things it doesn't understand...
1091	 */
1092	__le32	s_first_ino;		/* First non-reserved inode */
1093	__le16  s_inode_size;		/* size of inode structure */
1094	__le16	s_block_group_nr;	/* block group # of this superblock */
1095	__le32	s_feature_compat;	/* compatible feature set */
1096/*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
1097	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
1098/*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
1099/*78*/	char	s_volume_name[16];	/* volume name */
1100/*88*/	char	s_last_mounted[64];	/* directory where last mounted */
1101/*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
1102	/*
1103	 * Performance hints.  Directory preallocation should only
1104	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
1105	 */
1106	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
1107	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
1108	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
1109	/*
1110	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
1111	 */
1112/*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
1113/*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
1114	__le32	s_journal_dev;		/* device number of journal file */
1115	__le32	s_last_orphan;		/* start of list of inodes to delete */
1116	__le32	s_hash_seed[4];		/* HTREE hash seed */
1117	__u8	s_def_hash_version;	/* Default hash version to use */
1118	__u8	s_jnl_backup_type;
1119	__le16  s_desc_size;		/* size of group descriptor */
1120/*100*/	__le32	s_default_mount_opts;
1121	__le32	s_first_meta_bg;	/* First metablock block group */
1122	__le32	s_mkfs_time;		/* When the filesystem was created */
1123	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
1124	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
1125/*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
1126	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
1127	__le32	s_free_blocks_count_hi;	/* Free blocks count */
1128	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
1129	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
1130	__le32	s_flags;		/* Miscellaneous flags */
1131	__le16  s_raid_stride;		/* RAID stride */
1132	__le16  s_mmp_update_interval;  /* # seconds to wait in MMP checking */
1133	__le64  s_mmp_block;            /* Block for multi-mount protection */
1134	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
1135	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
1136	__u8	s_checksum_type;	/* metadata checksum algorithm used */
1137	__le16  s_reserved_pad;
1138	__le64	s_kbytes_written;	/* nr of lifetime kilobytes written */
1139	__le32	s_snapshot_inum;	/* Inode number of active snapshot */
1140	__le32	s_snapshot_id;		/* sequential ID of active snapshot */
1141	__le64	s_snapshot_r_blocks_count; /* reserved blocks for active
1142					      snapshot's future use */
1143	__le32	s_snapshot_list;	/* inode number of the head of the
1144					   on-disk snapshot list */
1145#define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
1146	__le32	s_error_count;		/* number of fs errors */
1147	__le32	s_first_error_time;	/* first time an error happened */
1148	__le32	s_first_error_ino;	/* inode involved in first error */
1149	__le64	s_first_error_block;	/* block involved of first error */
1150	__u8	s_first_error_func[32];	/* function where the error happened */
1151	__le32	s_first_error_line;	/* line number where error happened */
1152	__le32	s_last_error_time;	/* most recent time of an error */
1153	__le32	s_last_error_ino;	/* inode involved in last error */
1154	__le32	s_last_error_line;	/* line number where error happened */
1155	__le64	s_last_error_block;	/* block involved of last error */
1156	__u8	s_last_error_func[32];	/* function where the error happened */
1157#define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_mount_opts)
1158	__u8	s_mount_opts[64];
1159	__le32	s_usr_quota_inum;	/* inode for tracking user quota */
1160	__le32	s_grp_quota_inum;	/* inode for tracking group quota */
1161	__le32	s_overhead_clusters;	/* overhead blocks/clusters in fs */
1162	__le32	s_reserved[108];	/* Padding to the end of the block */
1163	__le32	s_checksum;		/* crc32c(superblock) */
1164};
1165
1166#define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
1167
1168#ifdef __KERNEL__
1169
1170/*
1171 * run-time mount flags
1172 */
1173#define EXT4_MF_MNTDIR_SAMPLED	0x0001
1174#define EXT4_MF_FS_ABORTED	0x0002	/* Fatal error detected */
1175
1176/*
1177 * fourth extended-fs super-block data in memory
1178 */
1179struct ext4_sb_info {
1180	unsigned long s_desc_size;	/* Size of a group descriptor in bytes */
1181	unsigned long s_inodes_per_block;/* Number of inodes per block */
1182	unsigned long s_blocks_per_group;/* Number of blocks in a group */
1183	unsigned long s_clusters_per_group; /* Number of clusters in a group */
1184	unsigned long s_inodes_per_group;/* Number of inodes in a group */
1185	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */
1186	unsigned long s_gdb_count;	/* Number of group descriptor blocks */
1187	unsigned long s_desc_per_block;	/* Number of group descriptors per block */
1188	ext4_group_t s_groups_count;	/* Number of groups in the fs */
1189	ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
1190	unsigned long s_overhead;  /* # of fs overhead clusters */
1191	unsigned int s_cluster_ratio;	/* Number of blocks per cluster */
1192	unsigned int s_cluster_bits;	/* log2 of s_cluster_ratio */
1193	loff_t s_bitmap_maxbytes;	/* max bytes for bitmap files */
1194	struct buffer_head * s_sbh;	/* Buffer containing the super block */
1195	struct ext4_super_block *s_es;	/* Pointer to the super block in the buffer */
1196	struct buffer_head **s_group_desc;
1197	unsigned int s_mount_opt;
1198	unsigned int s_mount_opt2;
1199	unsigned int s_mount_flags;
1200	unsigned int s_def_mount_opt;
1201	ext4_fsblk_t s_sb_block;
1202	atomic64_t s_resv_clusters;
1203	kuid_t s_resuid;
1204	kgid_t s_resgid;
1205	unsigned short s_mount_state;
1206	unsigned short s_pad;
1207	int s_addr_per_block_bits;
1208	int s_desc_per_block_bits;
1209	int s_inode_size;
1210	int s_first_ino;
1211	unsigned int s_inode_readahead_blks;
1212	unsigned int s_inode_goal;
1213	spinlock_t s_next_gen_lock;
1214	u32 s_next_generation;
1215	u32 s_hash_seed[4];
1216	int s_def_hash_version;
1217	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
1218	struct percpu_counter s_freeclusters_counter;
1219	struct percpu_counter s_freeinodes_counter;
1220	struct percpu_counter s_dirs_counter;
1221	struct percpu_counter s_dirtyclusters_counter;
1222	struct blockgroup_lock *s_blockgroup_lock;
1223	struct proc_dir_entry *s_proc;
1224	struct kobject s_kobj;
1225	struct completion s_kobj_unregister;
1226	struct super_block *s_sb;
1227
1228	/* Journaling */
1229	struct journal_s *s_journal;
1230	struct list_head s_orphan;
1231	struct mutex s_orphan_lock;
1232	unsigned long s_resize_flags;		/* Flags indicating if there
1233						   is a resizer */
1234	unsigned long s_commit_interval;
1235	u32 s_max_batch_time;
1236	u32 s_min_batch_time;
1237	struct block_device *journal_bdev;
1238#ifdef CONFIG_QUOTA
1239	char *s_qf_names[MAXQUOTAS];		/* Names of quota files with journalled quota */
1240	int s_jquota_fmt;			/* Format of quota to use */
1241#endif
1242	unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
1243	struct rb_root system_blks;
1244
1245#ifdef EXTENTS_STATS
1246	/* ext4 extents stats */
1247	unsigned long s_ext_min;
1248	unsigned long s_ext_max;
1249	unsigned long s_depth_max;
1250	spinlock_t s_ext_stats_lock;
1251	unsigned long s_ext_blocks;
1252	unsigned long s_ext_extents;
1253#endif
1254
1255	/* for buddy allocator */
1256	struct ext4_group_info ***s_group_info;
1257	struct inode *s_buddy_cache;
1258	spinlock_t s_md_lock;
1259	unsigned short *s_mb_offsets;
1260	unsigned int *s_mb_maxs;
1261	unsigned int s_group_info_size;
1262
1263	/* tunables */
1264	unsigned long s_stripe;
1265	unsigned int s_mb_stream_request;
1266	unsigned int s_mb_max_to_scan;
1267	unsigned int s_mb_min_to_scan;
1268	unsigned int s_mb_stats;
1269	unsigned int s_mb_order2_reqs;
1270	unsigned int s_mb_group_prealloc;
1271	unsigned int s_max_dir_size_kb;
1272	/* where last allocation was done - for stream allocation */
1273	unsigned long s_mb_last_group;
1274	unsigned long s_mb_last_start;
1275
1276	/* stats for buddy allocator */
1277	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
1278	atomic_t s_bal_success;	/* we found long enough chunks */
1279	atomic_t s_bal_allocated;	/* in blocks */
1280	atomic_t s_bal_ex_scanned;	/* total extents scanned */
1281	atomic_t s_bal_goals;	/* goal hits */
1282	atomic_t s_bal_breaks;	/* too long searches */
1283	atomic_t s_bal_2orders;	/* 2^order hits */
1284	spinlock_t s_bal_lock;
1285	unsigned long s_mb_buddies_generated;
1286	unsigned long long s_mb_generation_time;
1287	atomic_t s_mb_lost_chunks;
1288	atomic_t s_mb_preallocated;
1289	atomic_t s_mb_discarded;
1290	atomic_t s_lock_busy;
1291
1292	/* locality groups */
1293	struct ext4_locality_group __percpu *s_locality_groups;
1294
1295	/* for write statistics */
1296	unsigned long s_sectors_written_start;
1297	u64 s_kbytes_written;
1298
1299	/* the size of zero-out chunk */
1300	unsigned int s_extent_max_zeroout_kb;
1301
1302	unsigned int s_log_groups_per_flex;
1303	struct flex_groups *s_flex_groups;
1304	ext4_group_t s_flex_groups_allocated;
1305
1306	/* workqueue for reserved extent conversions (buffered io) */
1307	struct workqueue_struct *rsv_conversion_wq;
1308
1309	/* timer for periodic error stats printing */
1310	struct timer_list s_err_report;
1311
1312	/* Lazy inode table initialization info */
1313	struct ext4_li_request *s_li_request;
1314	/* Wait multiplier for lazy initialization thread */
1315	unsigned int s_li_wait_mult;
1316
1317	/* Kernel thread for multiple mount protection */
1318	struct task_struct *s_mmp_tsk;
1319
1320	/* record the last minlen when FITRIM is called. */
1321	atomic_t s_last_trim_minblks;
1322
1323	/* Reference to checksum algorithm driver via cryptoapi */
1324	struct crypto_shash *s_chksum_driver;
1325
1326	/* Precomputed FS UUID checksum for seeding other checksums */
1327	__u32 s_csum_seed;
1328
1329	/* Reclaim extents from extent status tree */
1330	struct shrinker s_es_shrinker;
1331	struct list_head s_es_lru;
1332	unsigned long s_es_last_sorted;
1333	struct percpu_counter s_extent_cache_cnt;
1334	struct mb_cache *s_mb_cache;
1335	spinlock_t s_es_lru_lock ____cacheline_aligned_in_smp;
1336
1337	/* Ratelimit ext4 messages. */
1338	struct ratelimit_state s_err_ratelimit_state;
1339	struct ratelimit_state s_warning_ratelimit_state;
1340	struct ratelimit_state s_msg_ratelimit_state;
1341};
1342
1343static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1344{
1345	return sb->s_fs_info;
1346}
1347static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1348{
1349	return container_of(inode, struct ext4_inode_info, vfs_inode);
1350}
1351
1352static inline struct timespec ext4_current_time(struct inode *inode)
1353{
1354	return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1355		current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1356}
1357
1358static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1359{
1360	return ino == EXT4_ROOT_INO ||
1361		ino == EXT4_USR_QUOTA_INO ||
1362		ino == EXT4_GRP_QUOTA_INO ||
1363		ino == EXT4_BOOT_LOADER_INO ||
1364		ino == EXT4_JOURNAL_INO ||
1365		ino == EXT4_RESIZE_INO ||
1366		(ino >= EXT4_FIRST_INO(sb) &&
1367		 ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1368}
1369
1370static inline void ext4_set_io_unwritten_flag(struct inode *inode,
1371					      struct ext4_io_end *io_end)
1372{
1373	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
1374		io_end->flag |= EXT4_IO_END_UNWRITTEN;
1375		atomic_inc(&EXT4_I(inode)->i_unwritten);
1376	}
1377}
1378
1379static inline ext4_io_end_t *ext4_inode_aio(struct inode *inode)
1380{
1381	return inode->i_private;
1382}
1383
1384static inline void ext4_inode_aio_set(struct inode *inode, ext4_io_end_t *io)
1385{
1386	inode->i_private = io;
1387}
1388
1389/*
1390 * Inode dynamic state flags
1391 */
1392enum {
1393	EXT4_STATE_JDATA,		/* journaled data exists */
1394	EXT4_STATE_NEW,			/* inode is newly created */
1395	EXT4_STATE_XATTR,		/* has in-inode xattrs */
1396	EXT4_STATE_NO_EXPAND,		/* No space for expansion */
1397	EXT4_STATE_DA_ALLOC_CLOSE,	/* Alloc DA blks on close */
1398	EXT4_STATE_EXT_MIGRATE,		/* Inode is migrating */
1399	EXT4_STATE_DIO_UNWRITTEN,	/* need convert on dio done*/
1400	EXT4_STATE_NEWENTRY,		/* File just added to dir */
1401	EXT4_STATE_DELALLOC_RESERVED,	/* blks already reserved for delalloc */
1402	EXT4_STATE_DIOREAD_LOCK,	/* Disable support for dio read
1403					   nolocking */
1404	EXT4_STATE_MAY_INLINE_DATA,	/* may have in-inode data */
1405	EXT4_STATE_ORDERED_MODE,	/* data=ordered mode */
1406	EXT4_STATE_EXT_PRECACHED,	/* extents have been precached */
1407};
1408
1409#define EXT4_INODE_BIT_FNS(name, field, offset)				\
1410static inline int ext4_test_inode_##name(struct inode *inode, int bit)	\
1411{									\
1412	return test_bit(bit + (offset), &EXT4_I(inode)->i_##field);	\
1413}									\
1414static inline void ext4_set_inode_##name(struct inode *inode, int bit)	\
1415{									\
1416	set_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1417}									\
1418static inline void ext4_clear_inode_##name(struct inode *inode, int bit) \
1419{									\
1420	clear_bit(bit + (offset), &EXT4_I(inode)->i_##field);		\
1421}
1422
1423/* Add these declarations here only so that these functions can be
1424 * found by name.  Otherwise, they are very hard to locate. */
1425static inline int ext4_test_inode_flag(struct inode *inode, int bit);
1426static inline void ext4_set_inode_flag(struct inode *inode, int bit);
1427static inline void ext4_clear_inode_flag(struct inode *inode, int bit);
1428EXT4_INODE_BIT_FNS(flag, flags, 0)
1429
1430/* Add these declarations here only so that these functions can be
1431 * found by name.  Otherwise, they are very hard to locate. */
1432static inline int ext4_test_inode_state(struct inode *inode, int bit);
1433static inline void ext4_set_inode_state(struct inode *inode, int bit);
1434static inline void ext4_clear_inode_state(struct inode *inode, int bit);
1435#if (BITS_PER_LONG < 64)
1436EXT4_INODE_BIT_FNS(state, state_flags, 0)
1437
1438static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1439{
1440	(ei)->i_state_flags = 0;
1441}
1442#else
1443EXT4_INODE_BIT_FNS(state, flags, 32)
1444
1445static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
1446{
1447	/* We depend on the fact that callers will set i_flags */
1448}
1449#endif
1450#else
1451/* Assume that user mode programs are passing in an ext4fs superblock, not
1452 * a kernel struct super_block.  This will allow us to call the feature-test
1453 * macros from user land. */
1454#define EXT4_SB(sb)	(sb)
1455#endif
1456
1457#define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1458
1459/*
1460 * Codes for operating systems
1461 */
1462#define EXT4_OS_LINUX		0
1463#define EXT4_OS_HURD		1
1464#define EXT4_OS_MASIX		2
1465#define EXT4_OS_FREEBSD		3
1466#define EXT4_OS_LITES		4
1467
1468/*
1469 * Revision levels
1470 */
1471#define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
1472#define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
1473
1474#define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
1475#define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
1476
1477#define EXT4_GOOD_OLD_INODE_SIZE 128
1478
1479/*
1480 * Feature set definitions
1481 */
1482
1483#define EXT4_HAS_COMPAT_FEATURE(sb,mask)			\
1484	((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1485#define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)			\
1486	((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1487#define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)			\
1488	((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1489#define EXT4_SET_COMPAT_FEATURE(sb,mask)			\
1490	EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1491#define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)			\
1492	EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1493#define EXT4_SET_INCOMPAT_FEATURE(sb,mask)			\
1494	EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1495#define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)			\
1496	EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1497#define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
1498	EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1499#define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
1500	EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1501
1502#define EXT4_FEATURE_COMPAT_DIR_PREALLOC	0x0001
1503#define EXT4_FEATURE_COMPAT_IMAGIC_INODES	0x0002
1504#define EXT4_FEATURE_COMPAT_HAS_JOURNAL		0x0004
1505#define EXT4_FEATURE_COMPAT_EXT_ATTR		0x0008
1506#define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
1507#define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
1508
1509#define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
1510#define EXT4_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
1511#define EXT4_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
1512#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1513#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
1514#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
1515#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
1516#define EXT4_FEATURE_RO_COMPAT_QUOTA		0x0100
1517#define EXT4_FEATURE_RO_COMPAT_BIGALLOC		0x0200
1518/*
1519 * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
1520 * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
1521 * all other data structures' checksums.  However, the METADATA_CSUM and
1522 * GDT_CSUM bits are mutually exclusive.
1523 */
1524#define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM	0x0400
1525
1526#define EXT4_FEATURE_INCOMPAT_COMPRESSION	0x0001
1527#define EXT4_FEATURE_INCOMPAT_FILETYPE		0x0002
1528#define EXT4_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
1529#define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
1530#define EXT4_FEATURE_INCOMPAT_META_BG		0x0010
1531#define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
1532#define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
1533#define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1534#define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
1535#define EXT4_FEATURE_INCOMPAT_EA_INODE		0x0400 /* EA in inode */
1536#define EXT4_FEATURE_INCOMPAT_DIRDATA		0x1000 /* data in dirent */
1537#define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM	0x2000 /* use crc32c for bg */
1538#define EXT4_FEATURE_INCOMPAT_LARGEDIR		0x4000 /* >2GB or 3-lvl htree */
1539#define EXT4_FEATURE_INCOMPAT_INLINE_DATA	0x8000 /* data in inode */
1540
1541#define EXT2_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1542#define EXT2_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1543					 EXT4_FEATURE_INCOMPAT_META_BG)
1544#define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1545					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1546					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1547
1548#define EXT3_FEATURE_COMPAT_SUPP	EXT4_FEATURE_COMPAT_EXT_ATTR
1549#define EXT3_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1550					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1551					 EXT4_FEATURE_INCOMPAT_META_BG)
1552#define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1553					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1554					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
1555
1556#define EXT4_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR
1557#define EXT4_FEATURE_INCOMPAT_SUPP	(EXT4_FEATURE_INCOMPAT_FILETYPE| \
1558					 EXT4_FEATURE_INCOMPAT_RECOVER| \
1559					 EXT4_FEATURE_INCOMPAT_META_BG| \
1560					 EXT4_FEATURE_INCOMPAT_EXTENTS| \
1561					 EXT4_FEATURE_INCOMPAT_64BIT| \
1562					 EXT4_FEATURE_INCOMPAT_FLEX_BG| \
1563					 EXT4_FEATURE_INCOMPAT_MMP |	\
1564					 EXT4_FEATURE_INCOMPAT_INLINE_DATA)
1565#define EXT4_FEATURE_RO_COMPAT_SUPP	(EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1566					 EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1567					 EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1568					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1569					 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1570					 EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1571					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
1572					 EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
1573					 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
1574					 EXT4_FEATURE_RO_COMPAT_QUOTA)
1575
1576/*
1577 * Default values for user and/or group using reserved blocks
1578 */
1579#define	EXT4_DEF_RESUID		0
1580#define	EXT4_DEF_RESGID		0
1581
1582#define EXT4_DEF_INODE_READAHEAD_BLKS	32
1583
1584/*
1585 * Default mount options
1586 */
1587#define EXT4_DEFM_DEBUG		0x0001
1588#define EXT4_DEFM_BSDGROUPS	0x0002
1589#define EXT4_DEFM_XATTR_USER	0x0004
1590#define EXT4_DEFM_ACL		0x0008
1591#define EXT4_DEFM_UID16		0x0010
1592#define EXT4_DEFM_JMODE		0x0060
1593#define EXT4_DEFM_JMODE_DATA	0x0020
1594#define EXT4_DEFM_JMODE_ORDERED	0x0040
1595#define EXT4_DEFM_JMODE_WBACK	0x0060
1596#define EXT4_DEFM_NOBARRIER	0x0100
1597#define EXT4_DEFM_BLOCK_VALIDITY 0x0200
1598#define EXT4_DEFM_DISCARD	0x0400
1599#define EXT4_DEFM_NODELALLOC	0x0800
1600
1601/*
1602 * Default journal batch times
1603 */
1604#define EXT4_DEF_MIN_BATCH_TIME	0
1605#define EXT4_DEF_MAX_BATCH_TIME	15000 /* 15ms */
1606
1607/*
1608 * Minimum number of groups in a flexgroup before we separate out
1609 * directories into the first block group of a flexgroup
1610 */
1611#define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME	4
1612
1613/*
1614 * Structure of a directory entry
1615 */
1616#define EXT4_NAME_LEN 255
1617
1618struct ext4_dir_entry {
1619	__le32	inode;			/* Inode number */
1620	__le16	rec_len;		/* Directory entry length */
1621	__le16	name_len;		/* Name length */
1622	char	name[EXT4_NAME_LEN];	/* File name */
1623};
1624
1625/*
1626 * The new version of the directory entry.  Since EXT4 structures are
1627 * stored in intel byte order, and the name_len field could never be
1628 * bigger than 255 chars, it's safe to reclaim the extra byte for the
1629 * file_type field.
1630 */
1631struct ext4_dir_entry_2 {
1632	__le32	inode;			/* Inode number */
1633	__le16	rec_len;		/* Directory entry length */
1634	__u8	name_len;		/* Name length */
1635	__u8	file_type;
1636	char	name[EXT4_NAME_LEN];	/* File name */
1637};
1638
1639/*
1640 * This is a bogus directory entry at the end of each leaf block that
1641 * records checksums.
1642 */
1643struct ext4_dir_entry_tail {
1644	__le32	det_reserved_zero1;	/* Pretend to be unused */
1645	__le16	det_rec_len;		/* 12 */
1646	__u8	det_reserved_zero2;	/* Zero name length */
1647	__u8	det_reserved_ft;	/* 0xDE, fake file type */
1648	__le32	det_checksum;		/* crc32c(uuid+inum+dirblock) */
1649};
1650
1651#define EXT4_DIRENT_TAIL(block, blocksize) \
1652	((struct ext4_dir_entry_tail *)(((void *)(block)) + \
1653					((blocksize) - \
1654					 sizeof(struct ext4_dir_entry_tail))))
1655
1656/*
1657 * Ext4 directory file types.  Only the low 3 bits are used.  The
1658 * other bits are reserved for now.
1659 */
1660#define EXT4_FT_UNKNOWN		0
1661#define EXT4_FT_REG_FILE	1
1662#define EXT4_FT_DIR		2
1663#define EXT4_FT_CHRDEV		3
1664#define EXT4_FT_BLKDEV		4
1665#define EXT4_FT_FIFO		5
1666#define EXT4_FT_SOCK		6
1667#define EXT4_FT_SYMLINK		7
1668
1669#define EXT4_FT_MAX		8
1670
1671#define EXT4_FT_DIR_CSUM	0xDE
1672
1673/*
1674 * EXT4_DIR_PAD defines the directory entries boundaries
1675 *
1676 * NOTE: It must be a multiple of 4
1677 */
1678#define EXT4_DIR_PAD			4
1679#define EXT4_DIR_ROUND			(EXT4_DIR_PAD - 1)
1680#define EXT4_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT4_DIR_ROUND) & \
1681					 ~EXT4_DIR_ROUND)
1682#define EXT4_MAX_REC_LEN		((1<<16)-1)
1683
1684/*
1685 * If we ever get support for fs block sizes > page_size, we'll need
1686 * to remove the #if statements in the next two functions...
1687 */
1688static inline unsigned int
1689ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
1690{
1691	unsigned len = le16_to_cpu(dlen);
1692
1693#if (PAGE_CACHE_SIZE >= 65536)
1694	if (len == EXT4_MAX_REC_LEN || len == 0)
1695		return blocksize;
1696	return (len & 65532) | ((len & 3) << 16);
1697#else
1698	return len;
1699#endif
1700}
1701
1702static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
1703{
1704	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
1705		BUG();
1706#if (PAGE_CACHE_SIZE >= 65536)
1707	if (len < 65536)
1708		return cpu_to_le16(len);
1709	if (len == blocksize) {
1710		if (blocksize == 65536)
1711			return cpu_to_le16(EXT4_MAX_REC_LEN);
1712		else
1713			return cpu_to_le16(0);
1714	}
1715	return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
1716#else
1717	return cpu_to_le16(len);
1718#endif
1719}
1720
1721/*
1722 * Hash Tree Directory indexing
1723 * (c) Daniel Phillips, 2001
1724 */
1725
1726#define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1727				      EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1728		    ext4_test_inode_flag((dir), EXT4_INODE_INDEX))
1729#define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1730#define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1731
1732/* Legal values for the dx_root hash_version field: */
1733
1734#define DX_HASH_LEGACY		0
1735#define DX_HASH_HALF_MD4	1
1736#define DX_HASH_TEA		2
1737#define DX_HASH_LEGACY_UNSIGNED	3
1738#define DX_HASH_HALF_MD4_UNSIGNED	4
1739#define DX_HASH_TEA_UNSIGNED		5
1740
1741static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
1742			      const void *address, unsigned int length)
1743{
1744	struct {
1745		struct shash_desc shash;
1746		char ctx[4];
1747	} desc;
1748	int err;
1749
1750	BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver)!=sizeof(desc.ctx));
1751
1752	desc.shash.tfm = sbi->s_chksum_driver;
1753	desc.shash.flags = 0;
1754	*(u32 *)desc.ctx = crc;
1755
1756	err = crypto_shash_update(&desc.shash, address, length);
1757	BUG_ON(err);
1758
1759	return *(u32 *)desc.ctx;
1760}
1761
1762#ifdef __KERNEL__
1763
1764/* hash info structure used by the directory hash */
1765struct dx_hash_info
1766{
1767	u32		hash;
1768	u32		minor_hash;
1769	int		hash_version;
1770	u32		*seed;
1771};
1772
1773
1774/* 32 and 64 bit signed EOF for dx directories */
1775#define EXT4_HTREE_EOF_32BIT   ((1UL  << (32 - 1)) - 1)
1776#define EXT4_HTREE_EOF_64BIT   ((1ULL << (64 - 1)) - 1)
1777
1778
1779/*
1780 * Control parameters used by ext4_htree_next_block
1781 */
1782#define HASH_NB_ALWAYS		1
1783
1784
1785/*
1786 * Describe an inode's exact location on disk and in memory
1787 */
1788struct ext4_iloc
1789{
1790	struct buffer_head *bh;
1791	unsigned long offset;
1792	ext4_group_t block_group;
1793};
1794
1795static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1796{
1797	return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1798}
1799
1800/*
1801 * This structure is stuffed into the struct file's private_data field
1802 * for directories.  It is where we put information so that we can do
1803 * readdir operations in hash tree order.
1804 */
1805struct dir_private_info {
1806	struct rb_root	root;
1807	struct rb_node	*curr_node;
1808	struct fname	*extra_fname;
1809	loff_t		last_pos;
1810	__u32		curr_hash;
1811	__u32		curr_minor_hash;
1812	__u32		next_hash;
1813};
1814
1815/* calculate the first block number of the group */
1816static inline ext4_fsblk_t
1817ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1818{
1819	return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1820		le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1821}
1822
1823/*
1824 * Special error return code only used by dx_probe() and its callers.
1825 */
1826#define ERR_BAD_DX_DIR	-75000
1827
 
 
 
1828/*
1829 * Timeout and state flag for lazy initialization inode thread.
1830 */
1831#define EXT4_DEF_LI_WAIT_MULT			10
1832#define EXT4_DEF_LI_MAX_START_DELAY		5
1833#define EXT4_LAZYINIT_QUIT			0x0001
1834#define EXT4_LAZYINIT_RUNNING			0x0002
1835
1836/*
1837 * Lazy inode table initialization info
1838 */
1839struct ext4_lazy_init {
1840	unsigned long		li_state;
1841	struct list_head	li_request_list;
1842	struct mutex		li_list_mtx;
1843};
1844
1845struct ext4_li_request {
1846	struct super_block	*lr_super;
1847	struct ext4_sb_info	*lr_sbi;
1848	ext4_group_t		lr_next_group;
1849	struct list_head	lr_request;
1850	unsigned long		lr_next_sched;
1851	unsigned long		lr_timeout;
1852};
1853
1854struct ext4_features {
1855	struct kobject f_kobj;
1856	struct completion f_kobj_unregister;
1857};
1858
1859/*
1860 * This structure will be used for multiple mount protection. It will be
1861 * written into the block number saved in the s_mmp_block field in the
1862 * superblock. Programs that check MMP should assume that if
1863 * SEQ_FSCK (or any unknown code above SEQ_MAX) is present then it is NOT safe
1864 * to use the filesystem, regardless of how old the timestamp is.
1865 */
1866#define EXT4_MMP_MAGIC     0x004D4D50U /* ASCII for MMP */
1867#define EXT4_MMP_SEQ_CLEAN 0xFF4D4D50U /* mmp_seq value for clean unmount */
1868#define EXT4_MMP_SEQ_FSCK  0xE24D4D50U /* mmp_seq value when being fscked */
1869#define EXT4_MMP_SEQ_MAX   0xE24D4D4FU /* maximum valid mmp_seq value */
1870
1871struct mmp_struct {
1872	__le32	mmp_magic;		/* Magic number for MMP */
1873	__le32	mmp_seq;		/* Sequence no. updated periodically */
1874
1875	/*
1876	 * mmp_time, mmp_nodename & mmp_bdevname are only used for information
1877	 * purposes and do not affect the correctness of the algorithm
1878	 */
1879	__le64	mmp_time;		/* Time last updated */
1880	char	mmp_nodename[64];	/* Node which last updated MMP block */
1881	char	mmp_bdevname[32];	/* Bdev which last updated MMP block */
1882
1883	/*
1884	 * mmp_check_interval is used to verify if the MMP block has been
1885	 * updated on the block device. The value is updated based on the
1886	 * maximum time to write the MMP block during an update cycle.
1887	 */
1888	__le16	mmp_check_interval;
1889
1890	__le16	mmp_pad1;
1891	__le32	mmp_pad2[226];
1892	__le32	mmp_checksum;		/* crc32c(uuid+mmp_block) */
1893};
1894
1895/* arguments passed to the mmp thread */
1896struct mmpd_data {
1897	struct buffer_head *bh; /* bh from initial read_mmp_block() */
1898	struct super_block *sb;  /* super block of the fs */
1899};
1900
1901/*
1902 * Check interval multiplier
1903 * The MMP block is written every update interval and initially checked every
1904 * update interval x the multiplier (the value is then adapted based on the
1905 * write latency). The reason is that writes can be delayed under load and we
1906 * don't want readers to incorrectly assume that the filesystem is no longer
1907 * in use.
1908 */
1909#define EXT4_MMP_CHECK_MULT		2UL
1910
1911/*
1912 * Minimum interval for MMP checking in seconds.
1913 */
1914#define EXT4_MMP_MIN_CHECK_INTERVAL	5UL
1915
1916/*
1917 * Maximum interval for MMP checking in seconds.
1918 */
1919#define EXT4_MMP_MAX_CHECK_INTERVAL	300UL
1920
1921/*
1922 * Function prototypes
1923 */
1924
1925/*
1926 * Ok, these declarations are also in <linux/kernel.h> but none of the
1927 * ext4 source programs needs to include it so they are duplicated here.
1928 */
1929# define NORET_TYPE	/**/
1930# define ATTRIB_NORET	__attribute__((noreturn))
1931# define NORET_AND	noreturn,
1932
1933/* bitmap.c */
1934extern unsigned int ext4_count_free(char *bitmap, unsigned numchars);
1935void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1936				struct ext4_group_desc *gdp,
1937				struct buffer_head *bh, int sz);
1938int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1939				  struct ext4_group_desc *gdp,
1940				  struct buffer_head *bh, int sz);
1941void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
1942				struct ext4_group_desc *gdp,
1943				struct buffer_head *bh);
1944int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
1945				  struct ext4_group_desc *gdp,
1946				  struct buffer_head *bh);
1947
1948/* balloc.c */
1949extern void ext4_get_group_no_and_offset(struct super_block *sb,
1950					 ext4_fsblk_t blocknr,
1951					 ext4_group_t *blockgrpp,
1952					 ext4_grpblk_t *offsetp);
1953extern ext4_group_t ext4_get_group_number(struct super_block *sb,
1954					  ext4_fsblk_t block);
1955
1956extern void ext4_validate_block_bitmap(struct super_block *sb,
1957				       struct ext4_group_desc *desc,
1958				       ext4_group_t block_group,
1959				       struct buffer_head *bh);
1960extern unsigned int ext4_block_group(struct super_block *sb,
1961			ext4_fsblk_t blocknr);
1962extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1963			ext4_fsblk_t blocknr);
1964extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1965extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1966			ext4_group_t group);
1967extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1968					 ext4_fsblk_t goal,
1969					 unsigned int flags,
1970					 unsigned long *count,
1971					 int *errp);
1972extern int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
1973				    s64 nclusters, unsigned int flags);
1974extern ext4_fsblk_t ext4_count_free_clusters(struct super_block *);
1975extern void ext4_check_blocks_bitmap(struct super_block *);
1976extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1977						    ext4_group_t block_group,
1978						    struct buffer_head ** bh);
1979extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1980
1981extern struct buffer_head *ext4_read_block_bitmap_nowait(struct super_block *sb,
1982						ext4_group_t block_group);
1983extern int ext4_wait_block_bitmap(struct super_block *sb,
1984				  ext4_group_t block_group,
1985				  struct buffer_head *bh);
1986extern struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1987						  ext4_group_t block_group);
1988extern void ext4_init_block_bitmap(struct super_block *sb,
1989				   struct buffer_head *bh,
1990				   ext4_group_t group,
1991				   struct ext4_group_desc *desc);
1992extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
1993					      ext4_group_t block_group,
1994					      struct ext4_group_desc *gdp);
1995extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
1996					   ext4_group_t block_group,
1997					   struct ext4_group_desc *gdp);
1998ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
1999
2000/* dir.c */
2001extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
2002				  struct file *,
2003				  struct ext4_dir_entry_2 *,
2004				  struct buffer_head *, char *, int,
2005				  unsigned int);
2006#define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset)	\
2007	unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \
2008					(de), (bh), (buf), (size), (offset)))
2009extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
2010				    __u32 minor_hash,
2011				    struct ext4_dir_entry_2 *dirent);
2012extern void ext4_htree_free_dir_info(struct dir_private_info *p);
2013extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
2014			     struct buffer_head *bh,
2015			     void *buf, int buf_size,
2016			     const char *name, int namelen,
2017			     struct ext4_dir_entry_2 **dest_de);
2018void ext4_insert_dentry(struct inode *inode,
2019			struct ext4_dir_entry_2 *de,
2020			int buf_size,
2021			const char *name, int namelen);
2022static inline void ext4_update_dx_flag(struct inode *inode)
2023{
2024	if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
2025				     EXT4_FEATURE_COMPAT_DIR_INDEX))
2026		ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
2027}
2028static unsigned char ext4_filetype_table[] = {
2029	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
2030};
2031
2032static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
2033{
2034	if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) ||
2035	    (filetype >= EXT4_FT_MAX))
2036		return DT_UNKNOWN;
2037
2038	return ext4_filetype_table[filetype];
2039}
2040
2041/* fsync.c */
2042extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
 
2043
2044/* hash.c */
2045extern int ext4fs_dirhash(const char *name, int len, struct
2046			  dx_hash_info *hinfo);
2047
2048/* ialloc.c */
2049extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
2050				      const struct qstr *qstr, __u32 goal,
2051				      uid_t *owner, int handle_type,
2052				      unsigned int line_no, int nblocks);
2053
2054#define ext4_new_inode(handle, dir, mode, qstr, goal, owner) \
2055	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
2056			 0, 0, 0)
2057#define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
2058				    type, nblocks)		    \
2059	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
2060			 (type), __LINE__, (nblocks))
2061
2062
2063extern void ext4_free_inode(handle_t *, struct inode *);
2064extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
2065extern unsigned long ext4_count_free_inodes(struct super_block *);
2066extern unsigned long ext4_count_dirs(struct super_block *);
2067extern void ext4_check_inodes_bitmap(struct super_block *);
2068extern void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
2069extern int ext4_init_inode_table(struct super_block *sb,
2070				 ext4_group_t group, int barrier);
2071extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
2072
2073/* mballoc.c */
2074extern long ext4_mb_stats;
2075extern long ext4_mb_max_to_scan;
2076extern int ext4_mb_init(struct super_block *);
2077extern int ext4_mb_release(struct super_block *);
2078extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
2079				struct ext4_allocation_request *, int *);
2080extern int ext4_mb_reserve_blocks(struct super_block *, int);
2081extern void ext4_discard_preallocations(struct inode *);
2082extern int __init ext4_init_mballoc(void);
2083extern void ext4_exit_mballoc(void);
2084extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
2085			     struct buffer_head *bh, ext4_fsblk_t block,
2086			     unsigned long count, int flags);
2087extern int ext4_mb_alloc_groupinfo(struct super_block *sb,
2088				   ext4_group_t ngroups);
2089extern int ext4_mb_add_groupinfo(struct super_block *sb,
2090		ext4_group_t i, struct ext4_group_desc *desc);
2091extern int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
2092				ext4_fsblk_t block, unsigned long count);
2093extern int ext4_trim_fs(struct super_block *, struct fstrim_range *);
2094
2095/* inode.c */
2096struct buffer_head *ext4_getblk(handle_t *, struct inode *,
2097						ext4_lblk_t, int, int *);
2098struct buffer_head *ext4_bread(handle_t *, struct inode *,
2099						ext4_lblk_t, int, int *);
2100int ext4_get_block_write(struct inode *inode, sector_t iblock,
2101			 struct buffer_head *bh_result, int create);
2102int ext4_get_block(struct inode *inode, sector_t iblock,
2103				struct buffer_head *bh_result, int create);
2104int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
2105			   struct buffer_head *bh, int create);
2106int ext4_walk_page_buffers(handle_t *handle,
2107			   struct buffer_head *head,
2108			   unsigned from,
2109			   unsigned to,
2110			   int *partial,
2111			   int (*fn)(handle_t *handle,
2112				     struct buffer_head *bh));
2113int do_journal_get_write_access(handle_t *handle,
2114				struct buffer_head *bh);
2115#define FALL_BACK_TO_NONDELALLOC 1
2116#define CONVERT_INLINE_DATA	 2
2117
2118extern struct inode *ext4_iget(struct super_block *, unsigned long);
2119extern int  ext4_write_inode(struct inode *, struct writeback_control *);
2120extern int  ext4_setattr(struct dentry *, struct iattr *);
2121extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
2122				struct kstat *stat);
2123extern void ext4_evict_inode(struct inode *);
2124extern void ext4_clear_inode(struct inode *);
2125extern int  ext4_sync_inode(handle_t *, struct inode *);
2126extern void ext4_dirty_inode(struct inode *, int);
2127extern int ext4_change_inode_journal_flag(struct inode *, int);
2128extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
2129extern int ext4_inode_attach_jinode(struct inode *inode);
2130extern int ext4_can_truncate(struct inode *inode);
2131extern void ext4_truncate(struct inode *);
2132extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
2133extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
2134extern void ext4_set_inode_flags(struct inode *);
2135extern void ext4_get_inode_flags(struct ext4_inode_info *);
2136extern int ext4_alloc_da_blocks(struct inode *inode);
2137extern void ext4_set_aops(struct inode *inode);
2138extern int ext4_writepage_trans_blocks(struct inode *);
2139extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
2140extern int ext4_block_truncate_page(handle_t *handle,
2141		struct address_space *mapping, loff_t from);
2142extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
2143			     loff_t lstart, loff_t lend);
2144extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
2145extern qsize_t *ext4_get_reserved_space(struct inode *inode);
2146extern void ext4_da_update_reserve_space(struct inode *inode,
2147					int used, int quota_claim);
2148
2149/* indirect.c */
2150extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
2151				struct ext4_map_blocks *map, int flags);
2152extern ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
2153				const struct iovec *iov, loff_t offset,
2154				unsigned long nr_segs);
2155extern int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock);
2156extern int ext4_ind_trans_blocks(struct inode *inode, int nrblocks);
2157extern void ext4_ind_truncate(handle_t *, struct inode *inode);
2158extern int ext4_free_hole_blocks(handle_t *handle, struct inode *inode,
2159				 ext4_lblk_t first, ext4_lblk_t stop);
2160
2161/* ioctl.c */
2162extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
2163extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
2164
2165/* migrate.c */
2166extern int ext4_ext_migrate(struct inode *);
2167extern int ext4_ind_migrate(struct inode *inode);
2168
2169/* namei.c */
2170extern int ext4_dirent_csum_verify(struct inode *inode,
2171				   struct ext4_dir_entry *dirent);
2172extern int ext4_orphan_add(handle_t *, struct inode *);
2173extern int ext4_orphan_del(handle_t *, struct inode *);
2174extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
2175				__u32 start_minor_hash, __u32 *next_hash);
2176extern int search_dir(struct buffer_head *bh,
2177		      char *search_buf,
2178		      int buf_size,
2179		      struct inode *dir,
2180		      const struct qstr *d_name,
2181		      unsigned int offset,
2182		      struct ext4_dir_entry_2 **res_dir);
2183extern int ext4_generic_delete_entry(handle_t *handle,
2184				     struct inode *dir,
2185				     struct ext4_dir_entry_2 *de_del,
2186				     struct buffer_head *bh,
2187				     void *entry_buf,
2188				     int buf_size,
2189				     int csum_size);
2190
2191/* resize.c */
2192extern int ext4_group_add(struct super_block *sb,
2193				struct ext4_new_group_data *input);
2194extern int ext4_group_extend(struct super_block *sb,
2195				struct ext4_super_block *es,
2196				ext4_fsblk_t n_blocks_count);
2197extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
2198
2199/* super.c */
2200extern int ext4_calculate_overhead(struct super_block *sb);
2201extern int ext4_superblock_csum_verify(struct super_block *sb,
2202				       struct ext4_super_block *es);
2203extern void ext4_superblock_csum_set(struct super_block *sb);
 
2204extern void *ext4_kvmalloc(size_t size, gfp_t flags);
2205extern void *ext4_kvzalloc(size_t size, gfp_t flags);
2206extern void ext4_kvfree(void *ptr);
2207extern int ext4_alloc_flex_bg_array(struct super_block *sb,
2208				    ext4_group_t ngroup);
2209extern const char *ext4_decode_error(struct super_block *sb, int errno,
2210				     char nbuf[16]);
2211
2212extern __printf(4, 5)
2213void __ext4_error(struct super_block *, const char *, unsigned int,
2214		  const char *, ...);
 
 
2215extern __printf(5, 6)
2216void __ext4_error_inode(struct inode *, const char *, unsigned int, ext4_fsblk_t,
2217		      const char *, ...);
2218extern __printf(5, 6)
2219void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
2220		     const char *, ...);
2221extern void __ext4_std_error(struct super_block *, const char *,
2222			     unsigned int, int);
2223extern __printf(4, 5)
2224void __ext4_abort(struct super_block *, const char *, unsigned int,
2225		  const char *, ...);
 
 
2226extern __printf(4, 5)
2227void __ext4_warning(struct super_block *, const char *, unsigned int,
2228		    const char *, ...);
 
 
2229extern __printf(3, 4)
2230void __ext4_msg(struct super_block *, const char *, const char *, ...);
2231extern void __dump_mmp_msg(struct super_block *, struct mmp_struct *mmp,
2232			   const char *, unsigned int, const char *);
 
 
2233extern __printf(7, 8)
2234void __ext4_grp_locked_error(const char *, unsigned int,
2235			     struct super_block *, ext4_group_t,
2236			     unsigned long, ext4_fsblk_t,
2237			     const char *, ...);
2238
2239#ifdef CONFIG_PRINTK
2240
2241#define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2242	__ext4_error_inode(inode, func, line, block, fmt, ##__VA_ARGS__)
2243#define ext4_error_file(file, func, line, block, fmt, ...)		\
2244	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
2245#define ext4_error(sb, fmt, ...)					\
2246	__ext4_error(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2247#define ext4_abort(sb, fmt, ...)					\
2248	__ext4_abort(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2249#define ext4_warning(sb, fmt, ...)					\
2250	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
2251#define ext4_msg(sb, level, fmt, ...)				\
2252	__ext4_msg(sb, level, fmt, ##__VA_ARGS__)
2253#define dump_mmp_msg(sb, mmp, msg)					\
2254	__dump_mmp_msg(sb, mmp, __func__, __LINE__, msg)
2255#define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2256	__ext4_grp_locked_error(__func__, __LINE__, sb, grp, ino, block, \
2257				fmt, ##__VA_ARGS__)
2258
2259#else
2260
2261#define ext4_error_inode(inode, func, line, block, fmt, ...)		\
2262do {									\
2263	no_printk(fmt, ##__VA_ARGS__);					\
2264	__ext4_error_inode(inode, "", 0, block, " ");			\
2265} while (0)
2266#define ext4_error_file(file, func, line, block, fmt, ...)		\
2267do {									\
2268	no_printk(fmt, ##__VA_ARGS__);					\
2269	__ext4_error_file(file, "", 0, block, " ");			\
2270} while (0)
2271#define ext4_error(sb, fmt, ...)					\
2272do {									\
2273	no_printk(fmt, ##__VA_ARGS__);					\
2274	__ext4_error(sb, "", 0, " ");					\
2275} while (0)
2276#define ext4_abort(sb, fmt, ...)					\
2277do {									\
2278	no_printk(fmt, ##__VA_ARGS__);					\
2279	__ext4_abort(sb, "", 0, " ");					\
2280} while (0)
2281#define ext4_warning(sb, fmt, ...)					\
2282do {									\
2283	no_printk(fmt, ##__VA_ARGS__);					\
2284	__ext4_warning(sb, "", 0, " ");					\
2285} while (0)
2286#define ext4_msg(sb, level, fmt, ...)					\
2287do {									\
2288	no_printk(fmt, ##__VA_ARGS__);					\
2289	__ext4_msg(sb, "", " ");					\
2290} while (0)
2291#define dump_mmp_msg(sb, mmp, msg)					\
2292	__dump_mmp_msg(sb, mmp, "", 0, "")
2293#define ext4_grp_locked_error(sb, grp, ino, block, fmt, ...)		\
2294do {									\
2295	no_printk(fmt, ##__VA_ARGS__);				\
2296	__ext4_grp_locked_error("", 0, sb, grp, ino, block, " ");	\
2297} while (0)
2298
2299#endif
2300
2301extern void ext4_update_dynamic_rev(struct super_block *sb);
2302extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
2303					__u32 compat);
2304extern int ext4_update_rocompat_feature(handle_t *handle,
2305					struct super_block *sb,	__u32 rocompat);
2306extern int ext4_update_incompat_feature(handle_t *handle,
2307					struct super_block *sb,	__u32 incompat);
2308extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
2309				      struct ext4_group_desc *bg);
2310extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
2311				      struct ext4_group_desc *bg);
2312extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
2313				     struct ext4_group_desc *bg);
2314extern __u32 ext4_free_group_clusters(struct super_block *sb,
2315				      struct ext4_group_desc *bg);
2316extern __u32 ext4_free_inodes_count(struct super_block *sb,
2317				 struct ext4_group_desc *bg);
2318extern __u32 ext4_used_dirs_count(struct super_block *sb,
2319				struct ext4_group_desc *bg);
2320extern __u32 ext4_itable_unused_count(struct super_block *sb,
2321				   struct ext4_group_desc *bg);
2322extern void ext4_block_bitmap_set(struct super_block *sb,
2323				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2324extern void ext4_inode_bitmap_set(struct super_block *sb,
2325				  struct ext4_group_desc *bg, ext4_fsblk_t blk);
2326extern void ext4_inode_table_set(struct super_block *sb,
2327				 struct ext4_group_desc *bg, ext4_fsblk_t blk);
2328extern void ext4_free_group_clusters_set(struct super_block *sb,
2329					 struct ext4_group_desc *bg,
2330					 __u32 count);
2331extern void ext4_free_inodes_set(struct super_block *sb,
2332				struct ext4_group_desc *bg, __u32 count);
2333extern void ext4_used_dirs_set(struct super_block *sb,
2334				struct ext4_group_desc *bg, __u32 count);
2335extern void ext4_itable_unused_set(struct super_block *sb,
2336				   struct ext4_group_desc *bg, __u32 count);
2337extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
2338				       struct ext4_group_desc *gdp);
2339extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
2340				     struct ext4_group_desc *gdp);
2341extern int ext4_register_li_request(struct super_block *sb,
2342				    ext4_group_t first_not_zeroed);
2343
2344static inline int ext4_has_group_desc_csum(struct super_block *sb)
2345{
2346	return EXT4_HAS_RO_COMPAT_FEATURE(sb,
2347					  EXT4_FEATURE_RO_COMPAT_GDT_CSUM |
2348					  EXT4_FEATURE_RO_COMPAT_METADATA_CSUM);
2349}
2350
2351static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
2352{
2353	return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
2354		le32_to_cpu(es->s_blocks_count_lo);
2355}
2356
2357static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
2358{
2359	return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
2360		le32_to_cpu(es->s_r_blocks_count_lo);
2361}
2362
2363static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
2364{
2365	return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
2366		le32_to_cpu(es->s_free_blocks_count_lo);
2367}
2368
2369static inline void ext4_blocks_count_set(struct ext4_super_block *es,
2370					 ext4_fsblk_t blk)
2371{
2372	es->s_blocks_count_lo = cpu_to_le32((u32)blk);
2373	es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
2374}
2375
2376static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
2377					      ext4_fsblk_t blk)
2378{
2379	es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
2380	es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
2381}
2382
2383static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
2384					   ext4_fsblk_t blk)
2385{
2386	es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
2387	es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
2388}
2389
2390static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
2391{
2392	if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
2393		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
2394			le32_to_cpu(raw_inode->i_size_lo);
2395	else
2396		return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
2397}
2398
2399static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
2400{
2401	raw_inode->i_size_lo = cpu_to_le32(i_size);
2402	raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
2403}
2404
2405static inline
2406struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
2407					    ext4_group_t group)
2408{
2409	 struct ext4_group_info ***grp_info;
2410	 long indexv, indexh;
2411	 BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
2412	 grp_info = EXT4_SB(sb)->s_group_info;
2413	 indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
2414	 indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
2415	 return grp_info[indexv][indexh];
2416}
2417
2418/*
2419 * Reading s_groups_count requires using smp_rmb() afterwards.  See
2420 * the locking protocol documented in the comments of ext4_group_add()
2421 * in resize.c
2422 */
2423static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
2424{
2425	ext4_group_t	ngroups = EXT4_SB(sb)->s_groups_count;
2426
2427	smp_rmb();
2428	return ngroups;
2429}
2430
2431static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
2432					     ext4_group_t block_group)
2433{
2434	return block_group >> sbi->s_log_groups_per_flex;
2435}
2436
2437static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
2438{
2439	return 1 << sbi->s_log_groups_per_flex;
2440}
2441
2442#define ext4_std_error(sb, errno)				\
2443do {								\
2444	if ((errno))						\
2445		__ext4_std_error((sb), __func__, __LINE__, (errno));	\
2446} while (0)
2447
2448#ifdef CONFIG_SMP
2449/* Each CPU can accumulate percpu_counter_batch clusters in their local
2450 * counters. So we need to make sure we have free clusters more
2451 * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
2452 */
2453#define EXT4_FREECLUSTERS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
2454#else
2455#define EXT4_FREECLUSTERS_WATERMARK 0
2456#endif
2457
2458/* Update i_disksize. Requires i_mutex to avoid races with truncate */
2459static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
2460{
2461	WARN_ON_ONCE(S_ISREG(inode->i_mode) &&
2462		     !mutex_is_locked(&inode->i_mutex));
 
2463	down_write(&EXT4_I(inode)->i_data_sem);
2464	if (newsize > EXT4_I(inode)->i_disksize)
2465		EXT4_I(inode)->i_disksize = newsize;
2466	up_write(&EXT4_I(inode)->i_data_sem);
 
2467}
2468
2469struct ext4_group_info {
2470	unsigned long   bb_state;
2471	struct rb_root  bb_free_root;
2472	ext4_grpblk_t	bb_first_free;	/* first free block */
2473	ext4_grpblk_t	bb_free;	/* total free blocks */
2474	ext4_grpblk_t	bb_fragments;	/* nr of freespace fragments */
2475	ext4_grpblk_t	bb_largest_free_order;/* order of largest frag in BG */
2476	struct          list_head bb_prealloc_list;
2477#ifdef DOUBLE_CHECK
2478	void            *bb_bitmap;
2479#endif
2480	struct rw_semaphore alloc_sem;
2481	ext4_grpblk_t	bb_counters[];	/* Nr of free power-of-two-block
2482					 * regions, index is order.
2483					 * bb_counters[3] = 5 means
2484					 * 5 free 8-block regions. */
2485};
2486
2487#define EXT4_GROUP_INFO_NEED_INIT_BIT		0
2488#define EXT4_GROUP_INFO_WAS_TRIMMED_BIT		1
2489#define EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT	2
2490#define EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT	3
2491
2492#define EXT4_MB_GRP_NEED_INIT(grp)	\
2493	(test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
2494#define EXT4_MB_GRP_BBITMAP_CORRUPT(grp)	\
2495	(test_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2496#define EXT4_MB_GRP_IBITMAP_CORRUPT(grp)	\
2497	(test_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &((grp)->bb_state)))
2498
2499#define EXT4_MB_GRP_WAS_TRIMMED(grp)	\
2500	(test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2501#define EXT4_MB_GRP_SET_TRIMMED(grp)	\
2502	(set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2503#define EXT4_MB_GRP_CLEAR_TRIMMED(grp)	\
2504	(clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state)))
2505
2506#define EXT4_MAX_CONTENTION		8
2507#define EXT4_CONTENTION_THRESHOLD	2
2508
2509static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
2510					      ext4_group_t group)
2511{
2512	return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
2513}
2514
2515/*
2516 * Returns true if the filesystem is busy enough that attempts to
2517 * access the block group locks has run into contention.
2518 */
2519static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
2520{
2521	return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
2522}
2523
2524static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
2525{
2526	spinlock_t *lock = ext4_group_lock_ptr(sb, group);
2527	if (spin_trylock(lock))
2528		/*
2529		 * We're able to grab the lock right away, so drop the
2530		 * lock contention counter.
2531		 */
2532		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
2533	else {
2534		/*
2535		 * The lock is busy, so bump the contention counter,
2536		 * and then wait on the spin lock.
2537		 */
2538		atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
2539				  EXT4_MAX_CONTENTION);
2540		spin_lock(lock);
2541	}
2542}
2543
2544static inline void ext4_unlock_group(struct super_block *sb,
2545					ext4_group_t group)
2546{
2547	spin_unlock(ext4_group_lock_ptr(sb, group));
2548}
2549
 
 
 
 
 
 
 
 
 
2550/*
2551 * Block validity checking
2552 */
2553#define ext4_check_indirect_blockref(inode, bh)				\
2554	ext4_check_blockref(__func__, __LINE__, inode,			\
2555			    (__le32 *)(bh)->b_data,			\
2556			    EXT4_ADDR_PER_BLOCK((inode)->i_sb))
2557
2558#define ext4_ind_check_inode(inode)					\
2559	ext4_check_blockref(__func__, __LINE__, inode,			\
2560			    EXT4_I(inode)->i_data,			\
2561			    EXT4_NDIR_BLOCKS)
2562
2563/*
2564 * Inodes and files operations
2565 */
2566
2567/* dir.c */
2568extern const struct file_operations ext4_dir_operations;
2569
2570/* file.c */
2571extern const struct inode_operations ext4_file_inode_operations;
2572extern const struct file_operations ext4_file_operations;
2573extern loff_t ext4_llseek(struct file *file, loff_t offset, int origin);
2574extern void ext4_unwritten_wait(struct inode *inode);
2575
2576/* inline.c */
2577extern int ext4_has_inline_data(struct inode *inode);
2578extern int ext4_get_inline_size(struct inode *inode);
2579extern int ext4_get_max_inline_size(struct inode *inode);
2580extern int ext4_find_inline_data_nolock(struct inode *inode);
2581extern void ext4_write_inline_data(struct inode *inode,
2582				   struct ext4_iloc *iloc,
2583				   void *buffer, loff_t pos,
2584				   unsigned int len);
2585extern int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
2586				    unsigned int len);
2587extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
2588				 unsigned int len);
2589extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
2590
2591extern int ext4_readpage_inline(struct inode *inode, struct page *page);
2592extern int ext4_try_to_write_inline_data(struct address_space *mapping,
2593					 struct inode *inode,
2594					 loff_t pos, unsigned len,
2595					 unsigned flags,
2596					 struct page **pagep);
2597extern int ext4_write_inline_data_end(struct inode *inode,
2598				      loff_t pos, unsigned len,
2599				      unsigned copied,
2600				      struct page *page);
2601extern struct buffer_head *
2602ext4_journalled_write_inline_data(struct inode *inode,
2603				  unsigned len,
2604				  struct page *page);
2605extern int ext4_da_write_inline_data_begin(struct address_space *mapping,
2606					   struct inode *inode,
2607					   loff_t pos, unsigned len,
2608					   unsigned flags,
2609					   struct page **pagep,
2610					   void **fsdata);
2611extern int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
2612					 unsigned len, unsigned copied,
2613					 struct page *page);
2614extern int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry,
2615				     struct inode *inode);
2616extern int ext4_try_create_inline_dir(handle_t *handle,
2617				      struct inode *parent,
2618				      struct inode *inode);
2619extern int ext4_read_inline_dir(struct file *filp,
2620				struct dir_context *ctx,
2621				int *has_inline_data);
2622extern int htree_inlinedir_to_tree(struct file *dir_file,
2623				   struct inode *dir, ext4_lblk_t block,
2624				   struct dx_hash_info *hinfo,
2625				   __u32 start_hash, __u32 start_minor_hash,
2626				   int *has_inline_data);
2627extern struct buffer_head *ext4_find_inline_entry(struct inode *dir,
2628					const struct qstr *d_name,
2629					struct ext4_dir_entry_2 **res_dir,
2630					int *has_inline_data);
2631extern int ext4_delete_inline_entry(handle_t *handle,
2632				    struct inode *dir,
2633				    struct ext4_dir_entry_2 *de_del,
2634				    struct buffer_head *bh,
2635				    int *has_inline_data);
2636extern int empty_inline_dir(struct inode *dir, int *has_inline_data);
2637extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
2638					struct ext4_dir_entry_2 **parent_de,
2639					int *retval);
2640extern int ext4_inline_data_fiemap(struct inode *inode,
2641				   struct fiemap_extent_info *fieinfo,
2642				   int *has_inline);
2643extern int ext4_try_to_evict_inline_data(handle_t *handle,
2644					 struct inode *inode,
2645					 int needed);
2646extern void ext4_inline_data_truncate(struct inode *inode, int *has_inline);
2647
2648extern int ext4_convert_inline_data(struct inode *inode);
2649
2650/* namei.c */
2651extern const struct inode_operations ext4_dir_inode_operations;
2652extern const struct inode_operations ext4_special_inode_operations;
2653extern struct dentry *ext4_get_parent(struct dentry *child);
2654extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2655				 struct ext4_dir_entry_2 *de,
2656				 int blocksize, int csum_size,
2657				 unsigned int parent_ino, int dotdot_real_len);
2658extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
2659				   unsigned int blocksize);
2660extern int ext4_handle_dirty_dirent_node(handle_t *handle,
2661					 struct inode *inode,
2662					 struct buffer_head *bh);
2663#define S_SHIFT 12
2664static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
2665	[S_IFREG >> S_SHIFT]	= EXT4_FT_REG_FILE,
2666	[S_IFDIR >> S_SHIFT]	= EXT4_FT_DIR,
2667	[S_IFCHR >> S_SHIFT]	= EXT4_FT_CHRDEV,
2668	[S_IFBLK >> S_SHIFT]	= EXT4_FT_BLKDEV,
2669	[S_IFIFO >> S_SHIFT]	= EXT4_FT_FIFO,
2670	[S_IFSOCK >> S_SHIFT]	= EXT4_FT_SOCK,
2671	[S_IFLNK >> S_SHIFT]	= EXT4_FT_SYMLINK,
2672};
2673
2674static inline void ext4_set_de_type(struct super_block *sb,
2675				struct ext4_dir_entry_2 *de,
2676				umode_t mode) {
2677	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE))
2678		de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
2679}
2680
2681
2682/* symlink.c */
2683extern const struct inode_operations ext4_symlink_inode_operations;
2684extern const struct inode_operations ext4_fast_symlink_inode_operations;
2685
2686/* block_validity */
2687extern void ext4_release_system_zone(struct super_block *sb);
2688extern int ext4_setup_system_zone(struct super_block *sb);
2689extern int __init ext4_init_system_zone(void);
2690extern void ext4_exit_system_zone(void);
2691extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
2692				 ext4_fsblk_t start_blk,
2693				 unsigned int count);
2694extern int ext4_check_blockref(const char *, unsigned int,
2695			       struct inode *, __le32 *, unsigned int);
2696
2697/* extents.c */
2698struct ext4_ext_path;
2699struct ext4_extent;
2700
2701/*
2702 * Maximum number of logical blocks in a file; ext4_extent's ee_block is
2703 * __le32.
2704 */
2705#define EXT_MAX_BLOCKS	0xffffffff
2706
2707extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
2708extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
2709extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
 
2710extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
2711			       struct ext4_map_blocks *map, int flags);
2712extern void ext4_ext_truncate(handle_t *, struct inode *);
2713extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
2714				 ext4_lblk_t end);
2715extern void ext4_ext_init(struct super_block *);
2716extern void ext4_ext_release(struct super_block *);
2717extern long ext4_fallocate(struct file *file, int mode, loff_t offset,
2718			  loff_t len);
2719extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode,
2720					  loff_t offset, ssize_t len);
2721extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
2722			   struct ext4_map_blocks *map, int flags);
2723extern int ext4_ext_calc_metadata_amount(struct inode *inode,
2724					 ext4_lblk_t lblocks);
2725extern int ext4_extent_tree_init(handle_t *, struct inode *);
2726extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
2727						   int num,
2728						   struct ext4_ext_path *path);
2729extern int ext4_can_extents_be_merged(struct inode *inode,
2730				      struct ext4_extent *ex1,
2731				      struct ext4_extent *ex2);
2732extern int ext4_ext_insert_extent(handle_t *, struct inode *,
2733				  struct ext4_ext_path *,
2734				  struct ext4_extent *, int);
2735extern struct ext4_ext_path *ext4_ext_find_extent(struct inode *, ext4_lblk_t,
2736						  struct ext4_ext_path *,
2737						  int flags);
2738extern void ext4_ext_drop_refs(struct ext4_ext_path *);
2739extern int ext4_ext_check_inode(struct inode *inode);
2740extern int ext4_find_delalloc_range(struct inode *inode,
2741				    ext4_lblk_t lblk_start,
2742				    ext4_lblk_t lblk_end);
2743extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk);
2744extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
2745			__u64 start, __u64 len);
2746extern int ext4_ext_precache(struct inode *inode);
2747extern int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len);
2748
2749/* move_extent.c */
2750extern void ext4_double_down_write_data_sem(struct inode *first,
2751					    struct inode *second);
2752extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
2753					  struct inode *donor_inode);
2754extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
2755			     __u64 start_orig, __u64 start_donor,
2756			     __u64 len, __u64 *moved_len);
2757extern int mext_next_extent(struct inode *inode, struct ext4_ext_path *path,
2758			    struct ext4_extent **extent);
2759
2760/* page-io.c */
2761extern int __init ext4_init_pageio(void);
2762extern void ext4_exit_pageio(void);
 
 
2763extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
2764extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
2765extern int ext4_put_io_end(ext4_io_end_t *io_end);
2766extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
2767extern void ext4_io_submit_init(struct ext4_io_submit *io,
2768				struct writeback_control *wbc);
2769extern void ext4_end_io_rsv_work(struct work_struct *work);
2770extern void ext4_io_submit(struct ext4_io_submit *io);
2771extern int ext4_bio_write_page(struct ext4_io_submit *io,
2772			       struct page *page,
2773			       int len,
2774			       struct writeback_control *wbc);
2775
2776/* mmp.c */
2777extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
2778extern void ext4_mmp_csum_set(struct super_block *sb, struct mmp_struct *mmp);
2779extern int ext4_mmp_csum_verify(struct super_block *sb,
2780				struct mmp_struct *mmp);
2781
2782/*
2783 * Note that these flags will never ever appear in a buffer_head's state flag.
2784 * See EXT4_MAP_... to see where this is used.
2785 */
2786enum ext4_state_bits {
2787	BH_Uninit	/* blocks are allocated but uninitialized on disk */
2788	 = BH_JBDPrivateStart,
2789	BH_AllocFromCluster,	/* allocated blocks were part of already
2790				 * allocated cluster. */
 
 
 
 
 
 
2791};
2792
 
 
 
 
2793/*
2794 * Add new method to test whether block and inode bitmaps are properly
2795 * initialized. With uninit_bg reading the block from disk is not enough
2796 * to mark the bitmap uptodate. We need to also zero-out the bitmap
2797 */
2798#define BH_BITMAP_UPTODATE BH_JBDPrivateStart
2799
2800static inline int bitmap_uptodate(struct buffer_head *bh)
2801{
2802	return (buffer_uptodate(bh) &&
2803			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
2804}
2805static inline void set_bitmap_uptodate(struct buffer_head *bh)
2806{
2807	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
2808}
2809
2810/*
2811 * Disable DIO read nolock optimization, so new dioreaders will be forced
2812 * to grab i_mutex
2813 */
2814static inline void ext4_inode_block_unlocked_dio(struct inode *inode)
2815{
2816	ext4_set_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2817	smp_mb();
2818}
2819static inline void ext4_inode_resume_unlocked_dio(struct inode *inode)
2820{
2821	smp_mb();
2822	ext4_clear_inode_state(inode, EXT4_STATE_DIOREAD_LOCK);
2823}
2824
2825#define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
2826
2827/* For ioend & aio unwritten conversion wait queues */
2828#define EXT4_WQ_HASH_SZ		37
2829#define ext4_ioend_wq(v)   (&ext4__ioend_wq[((unsigned long)(v)) %\
2830					    EXT4_WQ_HASH_SZ])
2831#define ext4_aio_mutex(v)  (&ext4__aio_mutex[((unsigned long)(v)) %\
2832					     EXT4_WQ_HASH_SZ])
2833extern wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
2834extern struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
2835
2836#define EXT4_RESIZING	0
2837extern int ext4_resize_begin(struct super_block *sb);
2838extern void ext4_resize_end(struct super_block *sb);
2839
2840#endif	/* __KERNEL__ */
 
 
2841
2842#endif	/* _EXT4_H */