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v6.2
   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   4 * All Rights Reserved.
   5 */
   6#ifndef __XFS_FORMAT_H__
   7#define __XFS_FORMAT_H__
   8
   9/*
  10 * XFS On Disk Format Definitions
  11 *
  12 * This header file defines all the on-disk format definitions for
  13 * general XFS objects. Directory and attribute related objects are defined in
  14 * xfs_da_format.h, which log and log item formats are defined in
  15 * xfs_log_format.h. Everything else goes here.
  16 */
  17
  18struct xfs_mount;
  19struct xfs_trans;
  20struct xfs_inode;
  21struct xfs_buf;
  22struct xfs_ifork;
  23
  24/*
  25 * Super block
  26 * Fits into a sector-sized buffer at address 0 of each allocation group.
  27 * Only the first of these is ever updated except during growfs.
  28 */
  29#define	XFS_SB_MAGIC		0x58465342	/* 'XFSB' */
  30#define	XFS_SB_VERSION_1	1		/* 5.3, 6.0.1, 6.1 */
  31#define	XFS_SB_VERSION_2	2		/* 6.2 - attributes */
  32#define	XFS_SB_VERSION_3	3		/* 6.2 - new inode version */
  33#define	XFS_SB_VERSION_4	4		/* 6.2+ - bitmask version */
  34#define	XFS_SB_VERSION_5	5		/* CRC enabled filesystem */
  35#define	XFS_SB_VERSION_NUMBITS		0x000f
  36#define	XFS_SB_VERSION_ALLFBITS		0xfff0
  37#define	XFS_SB_VERSION_ATTRBIT		0x0010
  38#define	XFS_SB_VERSION_NLINKBIT		0x0020
  39#define	XFS_SB_VERSION_QUOTABIT		0x0040
  40#define	XFS_SB_VERSION_ALIGNBIT		0x0080
  41#define	XFS_SB_VERSION_DALIGNBIT	0x0100
  42#define	XFS_SB_VERSION_SHAREDBIT	0x0200
  43#define XFS_SB_VERSION_LOGV2BIT		0x0400
  44#define XFS_SB_VERSION_SECTORBIT	0x0800
  45#define	XFS_SB_VERSION_EXTFLGBIT	0x1000
  46#define	XFS_SB_VERSION_DIRV2BIT		0x2000
  47#define	XFS_SB_VERSION_BORGBIT		0x4000	/* ASCII only case-insens. */
  48#define	XFS_SB_VERSION_MOREBITSBIT	0x8000
  49
  50/*
  51 * The size of a single extended attribute on disk is limited by
  52 * the size of index values within the attribute entries themselves.
  53 * These are be16 fields, so we can only support attribute data
  54 * sizes up to 2^16 bytes in length.
  55 */
  56#define XFS_XATTR_SIZE_MAX (1 << 16)
  57
  58/*
  59 * Supported feature bit list is just all bits in the versionnum field because
  60 * we've used them all up and understand them all. Except, of course, for the
  61 * shared superblock bit, which nobody knows what it does and so is unsupported.
  62 */
  63#define	XFS_SB_VERSION_OKBITS		\
  64	((XFS_SB_VERSION_NUMBITS | XFS_SB_VERSION_ALLFBITS) & \
  65		~XFS_SB_VERSION_SHAREDBIT)
  66
  67/*
  68 * There are two words to hold XFS "feature" bits: the original
  69 * word, sb_versionnum, and sb_features2.  Whenever a bit is set in
  70 * sb_features2, the feature bit XFS_SB_VERSION_MOREBITSBIT must be set.
  71 *
  72 * These defines represent bits in sb_features2.
  73 */
  74#define XFS_SB_VERSION2_RESERVED1BIT	0x00000001
  75#define XFS_SB_VERSION2_LAZYSBCOUNTBIT	0x00000002	/* Superblk counters */
  76#define XFS_SB_VERSION2_RESERVED4BIT	0x00000004
  77#define XFS_SB_VERSION2_ATTR2BIT	0x00000008	/* Inline attr rework */
  78#define XFS_SB_VERSION2_PARENTBIT	0x00000010	/* parent pointers */
  79#define XFS_SB_VERSION2_PROJID32BIT	0x00000080	/* 32 bit project id */
  80#define XFS_SB_VERSION2_CRCBIT		0x00000100	/* metadata CRCs */
  81#define XFS_SB_VERSION2_FTYPE		0x00000200	/* inode type in dir */
  82
  83#define	XFS_SB_VERSION2_OKBITS		\
  84	(XFS_SB_VERSION2_LAZYSBCOUNTBIT	| \
  85	 XFS_SB_VERSION2_ATTR2BIT	| \
  86	 XFS_SB_VERSION2_PROJID32BIT	| \
  87	 XFS_SB_VERSION2_FTYPE)
  88
  89/* Maximum size of the xfs filesystem label, no terminating NULL */
  90#define XFSLABEL_MAX			12
  91
  92/*
  93 * Superblock - in core version.  Must match the ondisk version below.
  94 * Must be padded to 64 bit alignment.
  95 */
  96typedef struct xfs_sb {
  97	uint32_t	sb_magicnum;	/* magic number == XFS_SB_MAGIC */
  98	uint32_t	sb_blocksize;	/* logical block size, bytes */
  99	xfs_rfsblock_t	sb_dblocks;	/* number of data blocks */
 100	xfs_rfsblock_t	sb_rblocks;	/* number of realtime blocks */
 101	xfs_rtblock_t	sb_rextents;	/* number of realtime extents */
 102	uuid_t		sb_uuid;	/* user-visible file system unique id */
 103	xfs_fsblock_t	sb_logstart;	/* starting block of log if internal */
 104	xfs_ino_t	sb_rootino;	/* root inode number */
 105	xfs_ino_t	sb_rbmino;	/* bitmap inode for realtime extents */
 106	xfs_ino_t	sb_rsumino;	/* summary inode for rt bitmap */
 107	xfs_agblock_t	sb_rextsize;	/* realtime extent size, blocks */
 108	xfs_agblock_t	sb_agblocks;	/* size of an allocation group */
 109	xfs_agnumber_t	sb_agcount;	/* number of allocation groups */
 110	xfs_extlen_t	sb_rbmblocks;	/* number of rt bitmap blocks */
 111	xfs_extlen_t	sb_logblocks;	/* number of log blocks */
 112	uint16_t	sb_versionnum;	/* header version == XFS_SB_VERSION */
 113	uint16_t	sb_sectsize;	/* volume sector size, bytes */
 114	uint16_t	sb_inodesize;	/* inode size, bytes */
 115	uint16_t	sb_inopblock;	/* inodes per block */
 116	char		sb_fname[XFSLABEL_MAX]; /* file system name */
 117	uint8_t		sb_blocklog;	/* log2 of sb_blocksize */
 118	uint8_t		sb_sectlog;	/* log2 of sb_sectsize */
 119	uint8_t		sb_inodelog;	/* log2 of sb_inodesize */
 120	uint8_t		sb_inopblog;	/* log2 of sb_inopblock */
 121	uint8_t		sb_agblklog;	/* log2 of sb_agblocks (rounded up) */
 122	uint8_t		sb_rextslog;	/* log2 of sb_rextents */
 123	uint8_t		sb_inprogress;	/* mkfs is in progress, don't mount */
 124	uint8_t		sb_imax_pct;	/* max % of fs for inode space */
 125					/* statistics */
 126	/*
 127	 * These fields must remain contiguous.  If you really
 128	 * want to change their layout, make sure you fix the
 129	 * code in xfs_trans_apply_sb_deltas().
 130	 */
 131	uint64_t	sb_icount;	/* allocated inodes */
 132	uint64_t	sb_ifree;	/* free inodes */
 133	uint64_t	sb_fdblocks;	/* free data blocks */
 134	uint64_t	sb_frextents;	/* free realtime extents */
 135	/*
 136	 * End contiguous fields.
 137	 */
 138	xfs_ino_t	sb_uquotino;	/* user quota inode */
 139	xfs_ino_t	sb_gquotino;	/* group quota inode */
 140	uint16_t	sb_qflags;	/* quota flags */
 141	uint8_t		sb_flags;	/* misc. flags */
 142	uint8_t		sb_shared_vn;	/* shared version number */
 143	xfs_extlen_t	sb_inoalignmt;	/* inode chunk alignment, fsblocks */
 144	uint32_t	sb_unit;	/* stripe or raid unit */
 145	uint32_t	sb_width;	/* stripe or raid width */
 146	uint8_t		sb_dirblklog;	/* log2 of dir block size (fsbs) */
 147	uint8_t		sb_logsectlog;	/* log2 of the log sector size */
 148	uint16_t	sb_logsectsize;	/* sector size for the log, bytes */
 149	uint32_t	sb_logsunit;	/* stripe unit size for the log */
 150	uint32_t	sb_features2;	/* additional feature bits */
 151
 152	/*
 153	 * bad features2 field as a result of failing to pad the sb structure to
 154	 * 64 bits. Some machines will be using this field for features2 bits.
 155	 * Easiest just to mark it bad and not use it for anything else.
 156	 *
 157	 * This is not kept up to date in memory; it is always overwritten by
 158	 * the value in sb_features2 when formatting the incore superblock to
 159	 * the disk buffer.
 160	 */
 161	uint32_t	sb_bad_features2;
 162
 163	/* version 5 superblock fields start here */
 164
 165	/* feature masks */
 166	uint32_t	sb_features_compat;
 167	uint32_t	sb_features_ro_compat;
 168	uint32_t	sb_features_incompat;
 169	uint32_t	sb_features_log_incompat;
 170
 171	uint32_t	sb_crc;		/* superblock crc */
 172	xfs_extlen_t	sb_spino_align;	/* sparse inode chunk alignment */
 173
 174	xfs_ino_t	sb_pquotino;	/* project quota inode */
 175	xfs_lsn_t	sb_lsn;		/* last write sequence */
 176	uuid_t		sb_meta_uuid;	/* metadata file system unique id */
 177
 
 
 
 
 
 
 
 
 178	/* must be padded to 64 bit alignment */
 179} xfs_sb_t;
 180
 181#define XFS_SB_CRC_OFF		offsetof(struct xfs_sb, sb_crc)
 182
 183/*
 184 * Superblock - on disk version.  Must match the in core version above.
 185 * Must be padded to 64 bit alignment.
 186 */
 187struct xfs_dsb {
 188	__be32		sb_magicnum;	/* magic number == XFS_SB_MAGIC */
 189	__be32		sb_blocksize;	/* logical block size, bytes */
 190	__be64		sb_dblocks;	/* number of data blocks */
 191	__be64		sb_rblocks;	/* number of realtime blocks */
 192	__be64		sb_rextents;	/* number of realtime extents */
 193	uuid_t		sb_uuid;	/* user-visible file system unique id */
 194	__be64		sb_logstart;	/* starting block of log if internal */
 195	__be64		sb_rootino;	/* root inode number */
 196	__be64		sb_rbmino;	/* bitmap inode for realtime extents */
 197	__be64		sb_rsumino;	/* summary inode for rt bitmap */
 198	__be32		sb_rextsize;	/* realtime extent size, blocks */
 199	__be32		sb_agblocks;	/* size of an allocation group */
 200	__be32		sb_agcount;	/* number of allocation groups */
 201	__be32		sb_rbmblocks;	/* number of rt bitmap blocks */
 202	__be32		sb_logblocks;	/* number of log blocks */
 203	__be16		sb_versionnum;	/* header version == XFS_SB_VERSION */
 204	__be16		sb_sectsize;	/* volume sector size, bytes */
 205	__be16		sb_inodesize;	/* inode size, bytes */
 206	__be16		sb_inopblock;	/* inodes per block */
 207	char		sb_fname[XFSLABEL_MAX]; /* file system name */
 208	__u8		sb_blocklog;	/* log2 of sb_blocksize */
 209	__u8		sb_sectlog;	/* log2 of sb_sectsize */
 210	__u8		sb_inodelog;	/* log2 of sb_inodesize */
 211	__u8		sb_inopblog;	/* log2 of sb_inopblock */
 212	__u8		sb_agblklog;	/* log2 of sb_agblocks (rounded up) */
 213	__u8		sb_rextslog;	/* log2 of sb_rextents */
 214	__u8		sb_inprogress;	/* mkfs is in progress, don't mount */
 215	__u8		sb_imax_pct;	/* max % of fs for inode space */
 216					/* statistics */
 217	/*
 218	 * These fields must remain contiguous.  If you really
 219	 * want to change their layout, make sure you fix the
 220	 * code in xfs_trans_apply_sb_deltas().
 221	 */
 222	__be64		sb_icount;	/* allocated inodes */
 223	__be64		sb_ifree;	/* free inodes */
 224	__be64		sb_fdblocks;	/* free data blocks */
 225	__be64		sb_frextents;	/* free realtime extents */
 226	/*
 227	 * End contiguous fields.
 228	 */
 229	__be64		sb_uquotino;	/* user quota inode */
 230	__be64		sb_gquotino;	/* group quota inode */
 231	__be16		sb_qflags;	/* quota flags */
 232	__u8		sb_flags;	/* misc. flags */
 233	__u8		sb_shared_vn;	/* shared version number */
 234	__be32		sb_inoalignmt;	/* inode chunk alignment, fsblocks */
 235	__be32		sb_unit;	/* stripe or raid unit */
 236	__be32		sb_width;	/* stripe or raid width */
 237	__u8		sb_dirblklog;	/* log2 of dir block size (fsbs) */
 238	__u8		sb_logsectlog;	/* log2 of the log sector size */
 239	__be16		sb_logsectsize;	/* sector size for the log, bytes */
 240	__be32		sb_logsunit;	/* stripe unit size for the log */
 241	__be32		sb_features2;	/* additional feature bits */
 242	/*
 243	 * bad features2 field as a result of failing to pad the sb
 244	 * structure to 64 bits. Some machines will be using this field
 245	 * for features2 bits. Easiest just to mark it bad and not use
 246	 * it for anything else.
 247	 */
 248	__be32		sb_bad_features2;
 249
 250	/* version 5 superblock fields start here */
 251
 252	/* feature masks */
 253	__be32		sb_features_compat;
 254	__be32		sb_features_ro_compat;
 255	__be32		sb_features_incompat;
 256	__be32		sb_features_log_incompat;
 257
 258	__le32		sb_crc;		/* superblock crc */
 259	__be32		sb_spino_align;	/* sparse inode chunk alignment */
 260
 261	__be64		sb_pquotino;	/* project quota inode */
 262	__be64		sb_lsn;		/* last write sequence */
 263	uuid_t		sb_meta_uuid;	/* metadata file system unique id */
 264
 265	/* must be padded to 64 bit alignment */
 
 
 
 
 
 
 
 
 
 
 
 
 266};
 267
 
 
 268/*
 269 * Misc. Flags - warning - these will be cleared by xfs_repair unless
 270 * a feature bit is set when the flag is used.
 271 */
 272#define XFS_SBF_NOFLAGS		0x00	/* no flags set */
 273#define XFS_SBF_READONLY	0x01	/* only read-only mounts allowed */
 274
 275/*
 276 * define max. shared version we can interoperate with
 277 */
 278#define XFS_SB_MAX_SHARED_VN	0
 279
 280#define	XFS_SB_VERSION_NUM(sbp)	((sbp)->sb_versionnum & XFS_SB_VERSION_NUMBITS)
 281
 282static inline bool xfs_sb_is_v5(struct xfs_sb *sbp)
 283{
 284	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5;
 285}
 286
 287/*
 288 * Detect a mismatched features2 field.  Older kernels read/wrote
 289 * this into the wrong slot, so to be safe we keep them in sync.
 290 */
 291static inline bool xfs_sb_has_mismatched_features2(struct xfs_sb *sbp)
 292{
 293	return sbp->sb_bad_features2 != sbp->sb_features2;
 294}
 295
 296static inline bool xfs_sb_version_hasmorebits(struct xfs_sb *sbp)
 297{
 298	return xfs_sb_is_v5(sbp) ||
 299	       (sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT);
 300}
 301
 302static inline void xfs_sb_version_addattr(struct xfs_sb *sbp)
 303{
 304	sbp->sb_versionnum |= XFS_SB_VERSION_ATTRBIT;
 305}
 306
 307static inline void xfs_sb_version_addquota(struct xfs_sb *sbp)
 308{
 309	sbp->sb_versionnum |= XFS_SB_VERSION_QUOTABIT;
 310}
 311
 312static inline void xfs_sb_version_addattr2(struct xfs_sb *sbp)
 313{
 314	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
 315	sbp->sb_features2 |= XFS_SB_VERSION2_ATTR2BIT;
 316}
 317
 318static inline void xfs_sb_version_addprojid32(struct xfs_sb *sbp)
 319{
 320	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
 321	sbp->sb_features2 |= XFS_SB_VERSION2_PROJID32BIT;
 322}
 323
 324/*
 325 * Extended v5 superblock feature masks. These are to be used for new v5
 326 * superblock features only.
 327 *
 328 * Compat features are new features that old kernels will not notice or affect
 329 * and so can mount read-write without issues.
 330 *
 331 * RO-Compat (read only) are features that old kernels can read but will break
 332 * if they write. Hence only read-only mounts of such filesystems are allowed on
 333 * kernels that don't support the feature bit.
 334 *
 335 * InCompat features are features which old kernels will not understand and so
 336 * must not mount.
 337 *
 338 * Log-InCompat features are for changes to log formats or new transactions that
 339 * can't be replayed on older kernels. The fields are set when the filesystem is
 340 * mounted, and a clean unmount clears the fields.
 341 */
 342#define XFS_SB_FEAT_COMPAT_ALL 0
 343#define XFS_SB_FEAT_COMPAT_UNKNOWN	~XFS_SB_FEAT_COMPAT_ALL
 344static inline bool
 345xfs_sb_has_compat_feature(
 346	struct xfs_sb	*sbp,
 347	uint32_t	feature)
 348{
 349	return (sbp->sb_features_compat & feature) != 0;
 350}
 351
 352#define XFS_SB_FEAT_RO_COMPAT_FINOBT   (1 << 0)		/* free inode btree */
 353#define XFS_SB_FEAT_RO_COMPAT_RMAPBT   (1 << 1)		/* reverse map btree */
 354#define XFS_SB_FEAT_RO_COMPAT_REFLINK  (1 << 2)		/* reflinked files */
 355#define XFS_SB_FEAT_RO_COMPAT_INOBTCNT (1 << 3)		/* inobt block counts */
 356#define XFS_SB_FEAT_RO_COMPAT_ALL \
 357		(XFS_SB_FEAT_RO_COMPAT_FINOBT | \
 358		 XFS_SB_FEAT_RO_COMPAT_RMAPBT | \
 359		 XFS_SB_FEAT_RO_COMPAT_REFLINK| \
 360		 XFS_SB_FEAT_RO_COMPAT_INOBTCNT)
 361#define XFS_SB_FEAT_RO_COMPAT_UNKNOWN	~XFS_SB_FEAT_RO_COMPAT_ALL
 362static inline bool
 363xfs_sb_has_ro_compat_feature(
 364	struct xfs_sb	*sbp,
 365	uint32_t	feature)
 366{
 367	return (sbp->sb_features_ro_compat & feature) != 0;
 368}
 369
 370#define XFS_SB_FEAT_INCOMPAT_FTYPE	(1 << 0)	/* filetype in dirent */
 371#define XFS_SB_FEAT_INCOMPAT_SPINODES	(1 << 1)	/* sparse inode chunks */
 372#define XFS_SB_FEAT_INCOMPAT_META_UUID	(1 << 2)	/* metadata UUID */
 373#define XFS_SB_FEAT_INCOMPAT_BIGTIME	(1 << 3)	/* large timestamps */
 374#define XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR (1 << 4)	/* needs xfs_repair */
 375#define XFS_SB_FEAT_INCOMPAT_NREXT64	(1 << 5)	/* large extent counters */
 
 
 
 376#define XFS_SB_FEAT_INCOMPAT_ALL \
 377		(XFS_SB_FEAT_INCOMPAT_FTYPE|	\
 378		 XFS_SB_FEAT_INCOMPAT_SPINODES|	\
 379		 XFS_SB_FEAT_INCOMPAT_META_UUID| \
 380		 XFS_SB_FEAT_INCOMPAT_BIGTIME| \
 381		 XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR| \
 382		 XFS_SB_FEAT_INCOMPAT_NREXT64)
 
 
 
 383
 384#define XFS_SB_FEAT_INCOMPAT_UNKNOWN	~XFS_SB_FEAT_INCOMPAT_ALL
 385static inline bool
 386xfs_sb_has_incompat_feature(
 387	struct xfs_sb	*sbp,
 388	uint32_t	feature)
 389{
 390	return (sbp->sb_features_incompat & feature) != 0;
 391}
 392
 393#define XFS_SB_FEAT_INCOMPAT_LOG_XATTRS   (1 << 0)	/* Delayed Attributes */
 394#define XFS_SB_FEAT_INCOMPAT_LOG_ALL \
 395	(XFS_SB_FEAT_INCOMPAT_LOG_XATTRS)
 396#define XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN	~XFS_SB_FEAT_INCOMPAT_LOG_ALL
 397static inline bool
 398xfs_sb_has_incompat_log_feature(
 399	struct xfs_sb	*sbp,
 400	uint32_t	feature)
 401{
 402	return (sbp->sb_features_log_incompat & feature) != 0;
 403}
 404
 405static inline void
 406xfs_sb_remove_incompat_log_features(
 407	struct xfs_sb	*sbp)
 408{
 409	sbp->sb_features_log_incompat &= ~XFS_SB_FEAT_INCOMPAT_LOG_ALL;
 410}
 411
 412static inline void
 413xfs_sb_add_incompat_log_features(
 414	struct xfs_sb	*sbp,
 415	unsigned int	features)
 416{
 417	sbp->sb_features_log_incompat |= features;
 418}
 419
 420static inline bool xfs_sb_version_haslogxattrs(struct xfs_sb *sbp)
 421{
 422	return xfs_sb_is_v5(sbp) && (sbp->sb_features_log_incompat &
 423		 XFS_SB_FEAT_INCOMPAT_LOG_XATTRS);
 424}
 425
 426static inline bool
 427xfs_is_quota_inode(struct xfs_sb *sbp, xfs_ino_t ino)
 428{
 429	return (ino == sbp->sb_uquotino ||
 430		ino == sbp->sb_gquotino ||
 431		ino == sbp->sb_pquotino);
 432}
 433
 434#define XFS_SB_DADDR		((xfs_daddr_t)0) /* daddr in filesystem/ag */
 435#define	XFS_SB_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_SB_DADDR)
 436
 437#define	XFS_HDR_BLOCK(mp,d)	((xfs_agblock_t)XFS_BB_TO_FSBT(mp,d))
 438#define	XFS_DADDR_TO_FSB(mp,d)	XFS_AGB_TO_FSB(mp, \
 439			xfs_daddr_to_agno(mp,d), xfs_daddr_to_agbno(mp,d))
 440#define	XFS_FSB_TO_DADDR(mp,fsbno)	XFS_AGB_TO_DADDR(mp, \
 441			XFS_FSB_TO_AGNO(mp,fsbno), XFS_FSB_TO_AGBNO(mp,fsbno))
 442
 443/*
 444 * File system sector to basic block conversions.
 445 */
 446#define XFS_FSS_TO_BB(mp,sec)	((sec) << (mp)->m_sectbb_log)
 447
 448/*
 449 * File system block to basic block conversions.
 450 */
 451#define	XFS_FSB_TO_BB(mp,fsbno)	((fsbno) << (mp)->m_blkbb_log)
 452#define	XFS_BB_TO_FSB(mp,bb)	\
 453	(((bb) + (XFS_FSB_TO_BB(mp,1) - 1)) >> (mp)->m_blkbb_log)
 454#define	XFS_BB_TO_FSBT(mp,bb)	((bb) >> (mp)->m_blkbb_log)
 455
 456/*
 457 * File system block to byte conversions.
 458 */
 459#define XFS_FSB_TO_B(mp,fsbno)	((xfs_fsize_t)(fsbno) << (mp)->m_sb.sb_blocklog)
 460#define XFS_B_TO_FSB(mp,b)	\
 461	((((uint64_t)(b)) + (mp)->m_blockmask) >> (mp)->m_sb.sb_blocklog)
 462#define XFS_B_TO_FSBT(mp,b)	(((uint64_t)(b)) >> (mp)->m_sb.sb_blocklog)
 463
 464/*
 465 * Allocation group header
 466 *
 467 * This is divided into three structures, placed in sequential 512-byte
 468 * buffers after a copy of the superblock (also in a 512-byte buffer).
 469 */
 470#define	XFS_AGF_MAGIC	0x58414746	/* 'XAGF' */
 471#define	XFS_AGI_MAGIC	0x58414749	/* 'XAGI' */
 472#define	XFS_AGFL_MAGIC	0x5841464c	/* 'XAFL' */
 473#define	XFS_AGF_VERSION	1
 474#define	XFS_AGI_VERSION	1
 475
 476#define	XFS_AGF_GOOD_VERSION(v)	((v) == XFS_AGF_VERSION)
 477#define	XFS_AGI_GOOD_VERSION(v)	((v) == XFS_AGI_VERSION)
 478
 479/*
 480 * Btree number 0 is bno, 1 is cnt, 2 is rmap. This value gives the size of the
 481 * arrays below.
 482 */
 483#define	XFS_BTNUM_AGF	((int)XFS_BTNUM_RMAPi + 1)
 484
 485/*
 486 * The second word of agf_levels in the first a.g. overlaps the EFS
 487 * superblock's magic number.  Since the magic numbers valid for EFS
 488 * are > 64k, our value cannot be confused for an EFS superblock's.
 489 */
 490
 491typedef struct xfs_agf {
 492	/*
 493	 * Common allocation group header information
 494	 */
 495	__be32		agf_magicnum;	/* magic number == XFS_AGF_MAGIC */
 496	__be32		agf_versionnum;	/* header version == XFS_AGF_VERSION */
 497	__be32		agf_seqno;	/* sequence # starting from 0 */
 498	__be32		agf_length;	/* size in blocks of a.g. */
 499	/*
 500	 * Freespace and rmap information
 501	 */
 502	__be32		agf_roots[XFS_BTNUM_AGF];	/* root blocks */
 503	__be32		agf_levels[XFS_BTNUM_AGF];	/* btree levels */
 
 
 
 
 
 504
 505	__be32		agf_flfirst;	/* first freelist block's index */
 506	__be32		agf_fllast;	/* last freelist block's index */
 507	__be32		agf_flcount;	/* count of blocks in freelist */
 508	__be32		agf_freeblks;	/* total free blocks */
 509
 510	__be32		agf_longest;	/* longest free space */
 511	__be32		agf_btreeblks;	/* # of blocks held in AGF btrees */
 512	uuid_t		agf_uuid;	/* uuid of filesystem */
 513
 514	__be32		agf_rmap_blocks;	/* rmapbt blocks used */
 515	__be32		agf_refcount_blocks;	/* refcountbt blocks used */
 516
 517	__be32		agf_refcount_root;	/* refcount tree root block */
 518	__be32		agf_refcount_level;	/* refcount btree levels */
 519
 520	/*
 521	 * reserve some contiguous space for future logged fields before we add
 522	 * the unlogged fields. This makes the range logging via flags and
 523	 * structure offsets much simpler.
 524	 */
 525	__be64		agf_spare64[14];
 526
 527	/* unlogged fields, written during buffer writeback. */
 528	__be64		agf_lsn;	/* last write sequence */
 529	__be32		agf_crc;	/* crc of agf sector */
 530	__be32		agf_spare2;
 531
 532	/* structure must be padded to 64 bit alignment */
 533} xfs_agf_t;
 534
 535#define XFS_AGF_CRC_OFF		offsetof(struct xfs_agf, agf_crc)
 536
 537#define	XFS_AGF_MAGICNUM	(1u << 0)
 538#define	XFS_AGF_VERSIONNUM	(1u << 1)
 539#define	XFS_AGF_SEQNO		(1u << 2)
 540#define	XFS_AGF_LENGTH		(1u << 3)
 541#define	XFS_AGF_ROOTS		(1u << 4)
 542#define	XFS_AGF_LEVELS		(1u << 5)
 543#define	XFS_AGF_FLFIRST		(1u << 6)
 544#define	XFS_AGF_FLLAST		(1u << 7)
 545#define	XFS_AGF_FLCOUNT		(1u << 8)
 546#define	XFS_AGF_FREEBLKS	(1u << 9)
 547#define	XFS_AGF_LONGEST		(1u << 10)
 548#define	XFS_AGF_BTREEBLKS	(1u << 11)
 549#define	XFS_AGF_UUID		(1u << 12)
 550#define	XFS_AGF_RMAP_BLOCKS	(1u << 13)
 551#define	XFS_AGF_REFCOUNT_BLOCKS	(1u << 14)
 552#define	XFS_AGF_REFCOUNT_ROOT	(1u << 15)
 553#define	XFS_AGF_REFCOUNT_LEVEL	(1u << 16)
 554#define	XFS_AGF_SPARE64		(1u << 17)
 555#define	XFS_AGF_NUM_BITS	18
 556#define	XFS_AGF_ALL_BITS	((1u << XFS_AGF_NUM_BITS) - 1)
 557
 558#define XFS_AGF_FLAGS \
 559	{ XFS_AGF_MAGICNUM,	"MAGICNUM" }, \
 560	{ XFS_AGF_VERSIONNUM,	"VERSIONNUM" }, \
 561	{ XFS_AGF_SEQNO,	"SEQNO" }, \
 562	{ XFS_AGF_LENGTH,	"LENGTH" }, \
 563	{ XFS_AGF_ROOTS,	"ROOTS" }, \
 564	{ XFS_AGF_LEVELS,	"LEVELS" }, \
 565	{ XFS_AGF_FLFIRST,	"FLFIRST" }, \
 566	{ XFS_AGF_FLLAST,	"FLLAST" }, \
 567	{ XFS_AGF_FLCOUNT,	"FLCOUNT" }, \
 568	{ XFS_AGF_FREEBLKS,	"FREEBLKS" }, \
 569	{ XFS_AGF_LONGEST,	"LONGEST" }, \
 570	{ XFS_AGF_BTREEBLKS,	"BTREEBLKS" }, \
 571	{ XFS_AGF_UUID,		"UUID" }, \
 572	{ XFS_AGF_RMAP_BLOCKS,	"RMAP_BLOCKS" }, \
 573	{ XFS_AGF_REFCOUNT_BLOCKS,	"REFCOUNT_BLOCKS" }, \
 574	{ XFS_AGF_REFCOUNT_ROOT,	"REFCOUNT_ROOT" }, \
 575	{ XFS_AGF_REFCOUNT_LEVEL,	"REFCOUNT_LEVEL" }, \
 576	{ XFS_AGF_SPARE64,	"SPARE64" }
 577
 578/* disk block (xfs_daddr_t) in the AG */
 579#define XFS_AGF_DADDR(mp)	((xfs_daddr_t)(1 << (mp)->m_sectbb_log))
 580#define	XFS_AGF_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))
 581
 582/*
 583 * Size of the unlinked inode hash table in the agi.
 584 */
 585#define	XFS_AGI_UNLINKED_BUCKETS	64
 586
 587typedef struct xfs_agi {
 588	/*
 589	 * Common allocation group header information
 590	 */
 591	__be32		agi_magicnum;	/* magic number == XFS_AGI_MAGIC */
 592	__be32		agi_versionnum;	/* header version == XFS_AGI_VERSION */
 593	__be32		agi_seqno;	/* sequence # starting from 0 */
 594	__be32		agi_length;	/* size in blocks of a.g. */
 595	/*
 596	 * Inode information
 597	 * Inodes are mapped by interpreting the inode number, so no
 598	 * mapping data is needed here.
 599	 */
 600	__be32		agi_count;	/* count of allocated inodes */
 601	__be32		agi_root;	/* root of inode btree */
 602	__be32		agi_level;	/* levels in inode btree */
 603	__be32		agi_freecount;	/* number of free inodes */
 604
 605	__be32		agi_newino;	/* new inode just allocated */
 606	__be32		agi_dirino;	/* last directory inode chunk */
 607	/*
 608	 * Hash table of inodes which have been unlinked but are
 609	 * still being referenced.
 610	 */
 611	__be32		agi_unlinked[XFS_AGI_UNLINKED_BUCKETS];
 612	/*
 613	 * This marks the end of logging region 1 and start of logging region 2.
 614	 */
 615	uuid_t		agi_uuid;	/* uuid of filesystem */
 616	__be32		agi_crc;	/* crc of agi sector */
 617	__be32		agi_pad32;
 618	__be64		agi_lsn;	/* last write sequence */
 619
 620	__be32		agi_free_root; /* root of the free inode btree */
 621	__be32		agi_free_level;/* levels in free inode btree */
 622
 623	__be32		agi_iblocks;	/* inobt blocks used */
 624	__be32		agi_fblocks;	/* finobt blocks used */
 625
 626	/* structure must be padded to 64 bit alignment */
 627} xfs_agi_t;
 628
 629#define XFS_AGI_CRC_OFF		offsetof(struct xfs_agi, agi_crc)
 630
 631#define	XFS_AGI_MAGICNUM	(1u << 0)
 632#define	XFS_AGI_VERSIONNUM	(1u << 1)
 633#define	XFS_AGI_SEQNO		(1u << 2)
 634#define	XFS_AGI_LENGTH		(1u << 3)
 635#define	XFS_AGI_COUNT		(1u << 4)
 636#define	XFS_AGI_ROOT		(1u << 5)
 637#define	XFS_AGI_LEVEL		(1u << 6)
 638#define	XFS_AGI_FREECOUNT	(1u << 7)
 639#define	XFS_AGI_NEWINO		(1u << 8)
 640#define	XFS_AGI_DIRINO		(1u << 9)
 641#define	XFS_AGI_UNLINKED	(1u << 10)
 642#define	XFS_AGI_NUM_BITS_R1	11	/* end of the 1st agi logging region */
 643#define	XFS_AGI_ALL_BITS_R1	((1u << XFS_AGI_NUM_BITS_R1) - 1)
 644#define	XFS_AGI_FREE_ROOT	(1u << 11)
 645#define	XFS_AGI_FREE_LEVEL	(1u << 12)
 646#define	XFS_AGI_IBLOCKS		(1u << 13) /* both inobt/finobt block counters */
 647#define	XFS_AGI_NUM_BITS_R2	14
 648
 649/* disk block (xfs_daddr_t) in the AG */
 650#define XFS_AGI_DADDR(mp)	((xfs_daddr_t)(2 << (mp)->m_sectbb_log))
 651#define	XFS_AGI_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGI_DADDR(mp))
 652
 653/*
 654 * The third a.g. block contains the a.g. freelist, an array
 655 * of block pointers to blocks owned by the allocation btree code.
 656 */
 657#define XFS_AGFL_DADDR(mp)	((xfs_daddr_t)(3 << (mp)->m_sectbb_log))
 658#define	XFS_AGFL_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGFL_DADDR(mp))
 659#define	XFS_BUF_TO_AGFL(bp)	((struct xfs_agfl *)((bp)->b_addr))
 660
 661struct xfs_agfl {
 662	__be32		agfl_magicnum;
 663	__be32		agfl_seqno;
 664	uuid_t		agfl_uuid;
 665	__be64		agfl_lsn;
 666	__be32		agfl_crc;
 667} __attribute__((packed));
 668
 669#define XFS_AGFL_CRC_OFF	offsetof(struct xfs_agfl, agfl_crc)
 670
 671#define XFS_AGB_TO_FSB(mp,agno,agbno)	\
 672	(((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno))
 673#define	XFS_FSB_TO_AGNO(mp,fsbno)	\
 674	((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog))
 675#define	XFS_FSB_TO_AGBNO(mp,fsbno)	\
 676	((xfs_agblock_t)((fsbno) & xfs_mask32lo((mp)->m_sb.sb_agblklog)))
 677#define	XFS_AGB_TO_DADDR(mp,agno,agbno)	\
 678	((xfs_daddr_t)XFS_FSB_TO_BB(mp, \
 679		(xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno)))
 680#define	XFS_AG_DADDR(mp,agno,d)		(XFS_AGB_TO_DADDR(mp, agno, 0) + (d))
 681
 682/*
 683 * For checking for bad ranges of xfs_daddr_t's, covering multiple
 684 * allocation groups or a single xfs_daddr_t that's a superblock copy.
 685 */
 686#define	XFS_AG_CHECK_DADDR(mp,d,len)	\
 687	((len) == 1 ? \
 688	    ASSERT((d) == XFS_SB_DADDR || \
 689		   xfs_daddr_to_agbno(mp, d) != XFS_SB_DADDR) : \
 690	    ASSERT(xfs_daddr_to_agno(mp, d) == \
 691		   xfs_daddr_to_agno(mp, (d) + (len) - 1)))
 692
 693/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 694 * XFS Timestamps
 695 * ==============
 696 *
 697 * Traditional ondisk inode timestamps consist of signed 32-bit counters for
 698 * seconds and nanoseconds; time zero is the Unix epoch, Jan  1 00:00:00 UTC
 699 * 1970, which means that the timestamp epoch is the same as the Unix epoch.
 700 * Therefore, the ondisk min and max defined here can be used directly to
 701 * constrain the incore timestamps on a Unix system.  Note that we actually
 702 * encode a __be64 value on disk.
 703 *
 704 * When the bigtime feature is enabled, ondisk inode timestamps become an
 705 * unsigned 64-bit nanoseconds counter.  This means that the bigtime inode
 706 * timestamp epoch is the start of the classic timestamp range, which is
 707 * Dec 13 20:45:52 UTC 1901.  Because the epochs are not the same, callers
 708 * /must/ use the bigtime conversion functions when encoding and decoding raw
 709 * timestamps.
 710 */
 711typedef __be64 xfs_timestamp_t;
 712
 713/* Legacy timestamp encoding format. */
 714struct xfs_legacy_timestamp {
 715	__be32		t_sec;		/* timestamp seconds */
 716	__be32		t_nsec;		/* timestamp nanoseconds */
 717};
 718
 719/*
 720 * Smallest possible ondisk seconds value with traditional timestamps.  This
 721 * corresponds exactly with the incore timestamp Dec 13 20:45:52 UTC 1901.
 722 */
 723#define XFS_LEGACY_TIME_MIN	((int64_t)S32_MIN)
 724
 725/*
 726 * Largest possible ondisk seconds value with traditional timestamps.  This
 727 * corresponds exactly with the incore timestamp Jan 19 03:14:07 UTC 2038.
 728 */
 729#define XFS_LEGACY_TIME_MAX	((int64_t)S32_MAX)
 730
 731/*
 732 * Smallest possible ondisk seconds value with bigtime timestamps.  This
 733 * corresponds (after conversion to a Unix timestamp) with the traditional
 734 * minimum timestamp of Dec 13 20:45:52 UTC 1901.
 735 */
 736#define XFS_BIGTIME_TIME_MIN	((int64_t)0)
 737
 738/*
 739 * Largest supported ondisk seconds value with bigtime timestamps.  This
 740 * corresponds (after conversion to a Unix timestamp) with an incore timestamp
 741 * of Jul  2 20:20:24 UTC 2486.
 742 *
 743 * We round down the ondisk limit so that the bigtime quota and inode max
 744 * timestamps will be the same.
 745 */
 746#define XFS_BIGTIME_TIME_MAX	((int64_t)((-1ULL / NSEC_PER_SEC) & ~0x3ULL))
 747
 748/*
 749 * Bigtime epoch is set exactly to the minimum time value that a traditional
 750 * 32-bit timestamp can represent when using the Unix epoch as a reference.
 751 * Hence the Unix epoch is at a fixed offset into the supported bigtime
 752 * timestamp range.
 753 *
 754 * The bigtime epoch also matches the minimum value an on-disk 32-bit XFS
 755 * timestamp can represent so we will not lose any fidelity in converting
 756 * to/from unix and bigtime timestamps.
 757 *
 758 * The following conversion factor converts a seconds counter from the Unix
 759 * epoch to the bigtime epoch.
 760 */
 761#define XFS_BIGTIME_EPOCH_OFFSET	(-(int64_t)S32_MIN)
 762
 763/* Convert a timestamp from the Unix epoch to the bigtime epoch. */
 764static inline uint64_t xfs_unix_to_bigtime(time64_t unix_seconds)
 765{
 766	return (uint64_t)unix_seconds + XFS_BIGTIME_EPOCH_OFFSET;
 767}
 768
 769/* Convert a timestamp from the bigtime epoch to the Unix epoch. */
 770static inline time64_t xfs_bigtime_to_unix(uint64_t ondisk_seconds)
 771{
 772	return (time64_t)ondisk_seconds - XFS_BIGTIME_EPOCH_OFFSET;
 773}
 774
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 775/*
 776 * On-disk inode structure.
 777 *
 778 * This is just the header or "dinode core", the inode is expanded to fill a
 779 * variable size the leftover area split into a data and an attribute fork.
 780 * The format of the data and attribute fork depends on the format of the
 781 * inode as indicated by di_format and di_aformat.  To access the data and
 782 * attribute use the XFS_DFORK_DPTR, XFS_DFORK_APTR, and XFS_DFORK_PTR macros
 783 * below.
 784 *
 785 * There is a very similar struct xfs_log_dinode which matches the layout of
 786 * this structure, but is kept in native format instead of big endian.
 787 *
 788 * Note: di_flushiter is only used by v1/2 inodes - it's effectively a zeroed
 789 * padding field for v3 inodes.
 790 */
 791#define	XFS_DINODE_MAGIC		0x494e	/* 'IN' */
 792struct xfs_dinode {
 793	__be16		di_magic;	/* inode magic # = XFS_DINODE_MAGIC */
 794	__be16		di_mode;	/* mode and type of file */
 795	__u8		di_version;	/* inode version */
 796	__u8		di_format;	/* format of di_c data */
 797	__be16		di_onlink;	/* old number of links to file */
 798	__be32		di_uid;		/* owner's user id */
 799	__be32		di_gid;		/* owner's group id */
 800	__be32		di_nlink;	/* number of links to file */
 801	__be16		di_projid_lo;	/* lower part of owner's project id */
 802	__be16		di_projid_hi;	/* higher part owner's project id */
 803	union {
 804		/* Number of data fork extents if NREXT64 is set */
 805		__be64	di_big_nextents;
 806
 807		/* Padding for V3 inodes without NREXT64 set. */
 808		__be64	di_v3_pad;
 809
 810		/* Padding and inode flush counter for V2 inodes. */
 811		struct {
 812			__u8	di_v2_pad[6];
 813			__be16	di_flushiter;
 814		};
 815	};
 816	xfs_timestamp_t	di_atime;	/* time last accessed */
 817	xfs_timestamp_t	di_mtime;	/* time last modified */
 818	xfs_timestamp_t	di_ctime;	/* time created/inode modified */
 819	__be64		di_size;	/* number of bytes in file */
 820	__be64		di_nblocks;	/* # of direct & btree blocks used */
 821	__be32		di_extsize;	/* basic/minimum extent size for file */
 822	union {
 823		/*
 824		 * For V2 inodes and V3 inodes without NREXT64 set, this
 825		 * is the number of data and attr fork extents.
 826		 */
 827		struct {
 828			__be32	di_nextents;
 829			__be16	di_anextents;
 830		} __packed;
 831
 832		/* Number of attr fork extents if NREXT64 is set. */
 833		struct {
 834			__be32	di_big_anextents;
 835			__be16	di_nrext64_pad;
 836		} __packed;
 837	} __packed;
 838	__u8		di_forkoff;	/* attr fork offs, <<3 for 64b align */
 839	__s8		di_aformat;	/* format of attr fork's data */
 840	__be32		di_dmevmask;	/* DMIG event mask */
 841	__be16		di_dmstate;	/* DMIG state info */
 842	__be16		di_flags;	/* random flags, XFS_DIFLAG_... */
 843	__be32		di_gen;		/* generation number */
 844
 845	/* di_next_unlinked is the only non-core field in the old dinode */
 846	__be32		di_next_unlinked;/* agi unlinked list ptr */
 847
 848	/* start of the extended dinode, writable fields */
 849	__le32		di_crc;		/* CRC of the inode */
 850	__be64		di_changecount;	/* number of attribute changes */
 851	__be64		di_lsn;		/* flush sequence */
 852	__be64		di_flags2;	/* more random flags */
 853	__be32		di_cowextsize;	/* basic cow extent size for file */
 854	__u8		di_pad2[12];	/* more padding for future expansion */
 855
 856	/* fields only written to during inode creation */
 857	xfs_timestamp_t	di_crtime;	/* time created */
 858	__be64		di_ino;		/* inode number */
 859	uuid_t		di_uuid;	/* UUID of the filesystem */
 860
 861	/* structure must be padded to 64 bit alignment */
 862};
 863
 864#define XFS_DINODE_CRC_OFF	offsetof(struct xfs_dinode, di_crc)
 865
 866#define DI_MAX_FLUSH 0xffff
 867
 868/*
 869 * Size of the core inode on disk.  Version 1 and 2 inodes have
 870 * the same size, but version 3 has grown a few additional fields.
 871 */
 872static inline uint xfs_dinode_size(int version)
 873{
 874	if (version == 3)
 875		return sizeof(struct xfs_dinode);
 876	return offsetof(struct xfs_dinode, di_crc);
 877}
 878
 879/*
 880 * The 32 bit link count in the inode theoretically maxes out at UINT_MAX.
 881 * Since the pathconf interface is signed, we use 2^31 - 1 instead.
 882 */
 883#define	XFS_MAXLINK		((1U << 31) - 1U)
 884
 885/*
 
 
 
 
 
 
 886 * Values for di_format
 887 *
 888 * This enum is used in string mapping in xfs_trace.h; please keep the
 889 * TRACE_DEFINE_ENUMs for it up to date.
 890 */
 891enum xfs_dinode_fmt {
 892	XFS_DINODE_FMT_DEV,		/* xfs_dev_t */
 893	XFS_DINODE_FMT_LOCAL,		/* bulk data */
 894	XFS_DINODE_FMT_EXTENTS,		/* struct xfs_bmbt_rec */
 895	XFS_DINODE_FMT_BTREE,		/* struct xfs_bmdr_block */
 896	XFS_DINODE_FMT_UUID		/* added long ago, but never used */
 897};
 898
 899#define XFS_INODE_FORMAT_STR \
 900	{ XFS_DINODE_FMT_DEV,		"dev" }, \
 901	{ XFS_DINODE_FMT_LOCAL,		"local" }, \
 902	{ XFS_DINODE_FMT_EXTENTS,	"extent" }, \
 903	{ XFS_DINODE_FMT_BTREE,		"btree" }, \
 904	{ XFS_DINODE_FMT_UUID,		"uuid" }
 905
 906/*
 907 * Max values for extnum and aextnum.
 908 *
 909 * The original on-disk extent counts were held in signed fields, resulting in
 910 * maximum extent counts of 2^31 and 2^15 for the data and attr forks
 911 * respectively. Similarly the maximum extent length is limited to 2^21 blocks
 912 * by the 21-bit wide blockcount field of a BMBT extent record.
 913 *
 914 * The newly introduced data fork extent counter can hold a 64-bit value,
 915 * however the maximum number of extents in a file is also limited to 2^54
 916 * extents by the 54-bit wide startoff field of a BMBT extent record.
 917 *
 918 * It is further limited by the maximum supported file size of 2^63
 919 * *bytes*. This leads to a maximum extent count for maximally sized filesystem
 920 * blocks (64kB) of:
 921 *
 922 * 2^63 bytes / 2^16 bytes per block = 2^47 blocks
 923 *
 924 * Rounding up 47 to the nearest multiple of bits-per-byte results in 48. Hence
 925 * 2^48 was chosen as the maximum data fork extent count.
 926 *
 927 * The maximum file size that can be represented by the data fork extent counter
 928 * in the worst case occurs when all extents are 1 block in length and each
 929 * block is 1KB in size.
 930 *
 931 * With XFS_MAX_EXTCNT_DATA_FORK_SMALL representing maximum extent count and
 932 * with 1KB sized blocks, a file can reach upto,
 933 * 1KB * (2^31) = 2TB
 934 *
 935 * This is much larger than the theoretical maximum size of a directory
 936 * i.e. XFS_DIR2_SPACE_SIZE * XFS_DIR2_MAX_SPACES = ~96GB.
 937 *
 938 * Hence, a directory inode can never overflow its data fork extent counter.
 939 */
 940#define XFS_MAX_EXTCNT_DATA_FORK_LARGE	((xfs_extnum_t)((1ULL << 48) - 1))
 941#define XFS_MAX_EXTCNT_ATTR_FORK_LARGE	((xfs_extnum_t)((1ULL << 32) - 1))
 942#define XFS_MAX_EXTCNT_DATA_FORK_SMALL	((xfs_extnum_t)((1ULL << 31) - 1))
 943#define XFS_MAX_EXTCNT_ATTR_FORK_SMALL	((xfs_extnum_t)((1ULL << 15) - 1))
 944
 945/*
 946 * When we upgrade an inode to the large extent counts, the maximum value by
 947 * which the extent count can increase is bound by the change in size of the
 948 * on-disk field. No upgrade operation should ever be adding more than a few
 949 * tens of extents, so if we get a really large value it is a sign of a code bug
 950 * or corruption.
 951 */
 952#define XFS_MAX_EXTCNT_UPGRADE_NR	\
 953	min(XFS_MAX_EXTCNT_ATTR_FORK_LARGE - XFS_MAX_EXTCNT_ATTR_FORK_SMALL,	\
 954	    XFS_MAX_EXTCNT_DATA_FORK_LARGE - XFS_MAX_EXTCNT_DATA_FORK_SMALL)
 955
 956/*
 957 * Inode minimum and maximum sizes.
 958 */
 959#define	XFS_DINODE_MIN_LOG	8
 960#define	XFS_DINODE_MAX_LOG	11
 961#define	XFS_DINODE_MIN_SIZE	(1 << XFS_DINODE_MIN_LOG)
 962#define	XFS_DINODE_MAX_SIZE	(1 << XFS_DINODE_MAX_LOG)
 963
 964/*
 965 * Inode size for given fs.
 966 */
 967#define XFS_DINODE_SIZE(mp) \
 968	(xfs_has_v3inodes(mp) ? \
 969		sizeof(struct xfs_dinode) : \
 970		offsetof(struct xfs_dinode, di_crc))
 971#define XFS_LITINO(mp) \
 972	((mp)->m_sb.sb_inodesize - XFS_DINODE_SIZE(mp))
 973
 974/*
 975 * Inode data & attribute fork sizes, per inode.
 976 */
 977#define XFS_DFORK_BOFF(dip)		((int)((dip)->di_forkoff << 3))
 978
 979#define XFS_DFORK_DSIZE(dip,mp) \
 980	((dip)->di_forkoff ? XFS_DFORK_BOFF(dip) : XFS_LITINO(mp))
 981#define XFS_DFORK_ASIZE(dip,mp) \
 982	((dip)->di_forkoff ? XFS_LITINO(mp) - XFS_DFORK_BOFF(dip) : 0)
 983#define XFS_DFORK_SIZE(dip,mp,w) \
 984	((w) == XFS_DATA_FORK ? \
 985		XFS_DFORK_DSIZE(dip, mp) : \
 986		XFS_DFORK_ASIZE(dip, mp))
 987
 988#define XFS_DFORK_MAXEXT(dip, mp, w) \
 989	(XFS_DFORK_SIZE(dip, mp, w) / sizeof(struct xfs_bmbt_rec))
 990
 991/*
 992 * Return pointers to the data or attribute forks.
 993 */
 994#define XFS_DFORK_DPTR(dip) \
 995	((char *)dip + xfs_dinode_size(dip->di_version))
 996#define XFS_DFORK_APTR(dip)	\
 997	(XFS_DFORK_DPTR(dip) + XFS_DFORK_BOFF(dip))
 998#define XFS_DFORK_PTR(dip,w)	\
 999	((w) == XFS_DATA_FORK ? XFS_DFORK_DPTR(dip) : XFS_DFORK_APTR(dip))
1000
1001#define XFS_DFORK_FORMAT(dip,w) \
1002	((w) == XFS_DATA_FORK ? \
1003		(dip)->di_format : \
1004		(dip)->di_aformat)
1005
1006/*
1007 * For block and character special files the 32bit dev_t is stored at the
1008 * beginning of the data fork.
1009 */
1010static inline xfs_dev_t xfs_dinode_get_rdev(struct xfs_dinode *dip)
1011{
1012	return be32_to_cpu(*(__be32 *)XFS_DFORK_DPTR(dip));
1013}
1014
1015static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
1016{
1017	*(__be32 *)XFS_DFORK_DPTR(dip) = cpu_to_be32(rdev);
1018}
1019
1020/*
1021 * Values for di_flags
1022 */
1023#define XFS_DIFLAG_REALTIME_BIT  0	/* file's blocks come from rt area */
1024#define XFS_DIFLAG_PREALLOC_BIT  1	/* file space has been preallocated */
1025#define XFS_DIFLAG_NEWRTBM_BIT   2	/* for rtbitmap inode, new format */
1026#define XFS_DIFLAG_IMMUTABLE_BIT 3	/* inode is immutable */
1027#define XFS_DIFLAG_APPEND_BIT    4	/* inode is append-only */
1028#define XFS_DIFLAG_SYNC_BIT      5	/* inode is written synchronously */
1029#define XFS_DIFLAG_NOATIME_BIT   6	/* do not update atime */
1030#define XFS_DIFLAG_NODUMP_BIT    7	/* do not dump */
1031#define XFS_DIFLAG_RTINHERIT_BIT 8	/* create with realtime bit set */
1032#define XFS_DIFLAG_PROJINHERIT_BIT   9	/* create with parents projid */
1033#define XFS_DIFLAG_NOSYMLINKS_BIT   10	/* disallow symlink creation */
1034#define XFS_DIFLAG_EXTSIZE_BIT      11	/* inode extent size allocator hint */
1035#define XFS_DIFLAG_EXTSZINHERIT_BIT 12	/* inherit inode extent size */
1036#define XFS_DIFLAG_NODEFRAG_BIT     13	/* do not reorganize/defragment */
1037#define XFS_DIFLAG_FILESTREAM_BIT   14  /* use filestream allocator */
1038/* Do not use bit 15, di_flags is legacy and unchanging now */
1039
1040#define XFS_DIFLAG_REALTIME      (1 << XFS_DIFLAG_REALTIME_BIT)
1041#define XFS_DIFLAG_PREALLOC      (1 << XFS_DIFLAG_PREALLOC_BIT)
1042#define XFS_DIFLAG_NEWRTBM       (1 << XFS_DIFLAG_NEWRTBM_BIT)
1043#define XFS_DIFLAG_IMMUTABLE     (1 << XFS_DIFLAG_IMMUTABLE_BIT)
1044#define XFS_DIFLAG_APPEND        (1 << XFS_DIFLAG_APPEND_BIT)
1045#define XFS_DIFLAG_SYNC          (1 << XFS_DIFLAG_SYNC_BIT)
1046#define XFS_DIFLAG_NOATIME       (1 << XFS_DIFLAG_NOATIME_BIT)
1047#define XFS_DIFLAG_NODUMP        (1 << XFS_DIFLAG_NODUMP_BIT)
1048#define XFS_DIFLAG_RTINHERIT     (1 << XFS_DIFLAG_RTINHERIT_BIT)
1049#define XFS_DIFLAG_PROJINHERIT   (1 << XFS_DIFLAG_PROJINHERIT_BIT)
1050#define XFS_DIFLAG_NOSYMLINKS    (1 << XFS_DIFLAG_NOSYMLINKS_BIT)
1051#define XFS_DIFLAG_EXTSIZE       (1 << XFS_DIFLAG_EXTSIZE_BIT)
1052#define XFS_DIFLAG_EXTSZINHERIT  (1 << XFS_DIFLAG_EXTSZINHERIT_BIT)
1053#define XFS_DIFLAG_NODEFRAG      (1 << XFS_DIFLAG_NODEFRAG_BIT)
1054#define XFS_DIFLAG_FILESTREAM    (1 << XFS_DIFLAG_FILESTREAM_BIT)
1055
1056#define XFS_DIFLAG_ANY \
1057	(XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \
1058	 XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \
1059	 XFS_DIFLAG_NOATIME | XFS_DIFLAG_NODUMP | XFS_DIFLAG_RTINHERIT | \
1060	 XFS_DIFLAG_PROJINHERIT | XFS_DIFLAG_NOSYMLINKS | XFS_DIFLAG_EXTSIZE | \
1061	 XFS_DIFLAG_EXTSZINHERIT | XFS_DIFLAG_NODEFRAG | XFS_DIFLAG_FILESTREAM)
1062
1063/*
1064 * Values for di_flags2 These start by being exposed to userspace in the upper
1065 * 16 bits of the XFS_XFLAG_s range.
1066 */
1067#define XFS_DIFLAG2_DAX_BIT	0	/* use DAX for this inode */
1068#define XFS_DIFLAG2_REFLINK_BIT	1	/* file's blocks may be shared */
1069#define XFS_DIFLAG2_COWEXTSIZE_BIT   2  /* copy on write extent size hint */
1070#define XFS_DIFLAG2_BIGTIME_BIT	3	/* big timestamps */
1071#define XFS_DIFLAG2_NREXT64_BIT 4	/* large extent counters */
1072
1073#define XFS_DIFLAG2_DAX		(1 << XFS_DIFLAG2_DAX_BIT)
1074#define XFS_DIFLAG2_REFLINK     (1 << XFS_DIFLAG2_REFLINK_BIT)
1075#define XFS_DIFLAG2_COWEXTSIZE  (1 << XFS_DIFLAG2_COWEXTSIZE_BIT)
1076#define XFS_DIFLAG2_BIGTIME	(1 << XFS_DIFLAG2_BIGTIME_BIT)
1077#define XFS_DIFLAG2_NREXT64	(1 << XFS_DIFLAG2_NREXT64_BIT)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1078
1079#define XFS_DIFLAG2_ANY \
1080	(XFS_DIFLAG2_DAX | XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE | \
1081	 XFS_DIFLAG2_BIGTIME | XFS_DIFLAG2_NREXT64)
1082
1083static inline bool xfs_dinode_has_bigtime(const struct xfs_dinode *dip)
1084{
1085	return dip->di_version >= 3 &&
1086	       (dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_BIGTIME));
1087}
1088
1089static inline bool xfs_dinode_has_large_extent_counts(
1090	const struct xfs_dinode *dip)
1091{
1092	return dip->di_version >= 3 &&
1093	       (dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_NREXT64));
1094}
1095
 
 
 
 
 
 
1096/*
1097 * Inode number format:
1098 * low inopblog bits - offset in block
1099 * next agblklog bits - block number in ag
1100 * next agno_log bits - ag number
1101 * high agno_log-agblklog-inopblog bits - 0
1102 */
1103#define	XFS_INO_MASK(k)			(uint32_t)((1ULL << (k)) - 1)
1104#define	XFS_INO_OFFSET_BITS(mp)		(mp)->m_sb.sb_inopblog
1105#define	XFS_INO_AGBNO_BITS(mp)		(mp)->m_sb.sb_agblklog
1106#define	XFS_INO_AGINO_BITS(mp)		((mp)->m_ino_geo.agino_log)
1107#define	XFS_INO_AGNO_BITS(mp)		(mp)->m_agno_log
1108#define	XFS_INO_BITS(mp)		\
1109	XFS_INO_AGNO_BITS(mp) + XFS_INO_AGINO_BITS(mp)
1110#define	XFS_INO_TO_AGNO(mp,i)		\
1111	((xfs_agnumber_t)((i) >> XFS_INO_AGINO_BITS(mp)))
1112#define	XFS_INO_TO_AGINO(mp,i)		\
1113	((xfs_agino_t)(i) & XFS_INO_MASK(XFS_INO_AGINO_BITS(mp)))
1114#define	XFS_INO_TO_AGBNO(mp,i)		\
1115	(((xfs_agblock_t)(i) >> XFS_INO_OFFSET_BITS(mp)) & \
1116		XFS_INO_MASK(XFS_INO_AGBNO_BITS(mp)))
1117#define	XFS_INO_TO_OFFSET(mp,i)		\
1118	((int)(i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1119#define	XFS_INO_TO_FSB(mp,i)		\
1120	XFS_AGB_TO_FSB(mp, XFS_INO_TO_AGNO(mp,i), XFS_INO_TO_AGBNO(mp,i))
1121#define	XFS_AGINO_TO_INO(mp,a,i)	\
1122	(((xfs_ino_t)(a) << XFS_INO_AGINO_BITS(mp)) | (i))
1123#define	XFS_AGINO_TO_AGBNO(mp,i)	((i) >> XFS_INO_OFFSET_BITS(mp))
1124#define	XFS_AGINO_TO_OFFSET(mp,i)	\
1125	((i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1126#define	XFS_OFFBNO_TO_AGINO(mp,b,o)	\
1127	((xfs_agino_t)(((b) << XFS_INO_OFFSET_BITS(mp)) | (o)))
1128#define	XFS_FSB_TO_INO(mp, b)	((xfs_ino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
1129#define	XFS_AGB_TO_AGINO(mp, b)	((xfs_agino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
1130
1131#define	XFS_MAXINUMBER		((xfs_ino_t)((1ULL << 56) - 1ULL))
1132#define	XFS_MAXINUMBER_32	((xfs_ino_t)((1ULL << 32) - 1ULL))
1133
1134/*
1135 * RealTime Device format definitions
1136 */
1137
1138/* Min and max rt extent sizes, specified in bytes */
1139#define	XFS_MAX_RTEXTSIZE	(1024 * 1024 * 1024)	/* 1GB */
1140#define	XFS_DFL_RTEXTSIZE	(64 * 1024)	        /* 64kB */
1141#define	XFS_MIN_RTEXTSIZE	(4 * 1024)		/* 4kB */
1142
1143#define	XFS_BLOCKSIZE(mp)	((mp)->m_sb.sb_blocksize)
1144#define	XFS_BLOCKMASK(mp)	((mp)->m_blockmask)
1145#define	XFS_BLOCKWSIZE(mp)	((mp)->m_blockwsize)
1146#define	XFS_BLOCKWMASK(mp)	((mp)->m_blockwmask)
1147
1148/*
1149 * RT Summary and bit manipulation macros.
1150 */
1151#define	XFS_SUMOFFS(mp,ls,bb)	((int)((ls) * (mp)->m_sb.sb_rbmblocks + (bb)))
1152#define	XFS_SUMOFFSTOBLOCK(mp,s)	\
1153	(((s) * (uint)sizeof(xfs_suminfo_t)) >> (mp)->m_sb.sb_blocklog)
1154#define	XFS_SUMPTR(mp,bp,so)	\
1155	((xfs_suminfo_t *)((bp)->b_addr + \
1156		(((so) * (uint)sizeof(xfs_suminfo_t)) & XFS_BLOCKMASK(mp))))
1157
1158#define	XFS_BITTOBLOCK(mp,bi)	((bi) >> (mp)->m_blkbit_log)
1159#define	XFS_BLOCKTOBIT(mp,bb)	((bb) << (mp)->m_blkbit_log)
1160#define	XFS_BITTOWORD(mp,bi)	\
1161	((int)(((bi) >> XFS_NBWORDLOG) & XFS_BLOCKWMASK(mp)))
1162
1163#define	XFS_RTMIN(a,b)	((a) < (b) ? (a) : (b))
1164#define	XFS_RTMAX(a,b)	((a) > (b) ? (a) : (b))
1165
1166#define	XFS_RTLOBIT(w)	xfs_lowbit32(w)
1167#define	XFS_RTHIBIT(w)	xfs_highbit32(w)
1168
1169#define	XFS_RTBLOCKLOG(b)	xfs_highbit64(b)
 
1170
1171/*
1172 * Dquot and dquot block format definitions
1173 */
1174#define XFS_DQUOT_MAGIC		0x4451		/* 'DQ' */
1175#define XFS_DQUOT_VERSION	(uint8_t)0x01	/* latest version number */
1176
1177#define XFS_DQTYPE_USER		(1u << 0)	/* user dquot record */
1178#define XFS_DQTYPE_PROJ		(1u << 1)	/* project dquot record */
1179#define XFS_DQTYPE_GROUP	(1u << 2)	/* group dquot record */
1180#define XFS_DQTYPE_BIGTIME	(1u << 7)	/* large expiry timestamps */
1181
1182/* bitmask to determine if this is a user/group/project dquot */
1183#define XFS_DQTYPE_REC_MASK	(XFS_DQTYPE_USER | \
1184				 XFS_DQTYPE_PROJ | \
1185				 XFS_DQTYPE_GROUP)
1186
1187#define XFS_DQTYPE_ANY		(XFS_DQTYPE_REC_MASK | \
1188				 XFS_DQTYPE_BIGTIME)
1189
1190/*
1191 * XFS Quota Timers
1192 * ================
1193 *
1194 * Traditional quota grace period expiration timers are an unsigned 32-bit
1195 * seconds counter; time zero is the Unix epoch, Jan  1 00:00:01 UTC 1970.
1196 * Note that an expiration value of zero means that the quota limit has not
1197 * been reached, and therefore no expiration has been set.  Therefore, the
1198 * ondisk min and max defined here can be used directly to constrain the incore
1199 * quota expiration timestamps on a Unix system.
1200 *
1201 * When bigtime is enabled, we trade two bits of precision to expand the
1202 * expiration timeout range to match that of big inode timestamps.  The min and
1203 * max recorded here are the on-disk limits, not a Unix timestamp.
1204 *
1205 * The grace period for each quota type is stored in the root dquot (id = 0)
1206 * and is applied to a non-root dquot when it exceeds the soft or hard limits.
1207 * The length of quota grace periods are unsigned 32-bit quantities measured in
1208 * units of seconds.  A value of zero means to use the default period.
1209 */
1210
1211/*
1212 * Smallest possible ondisk quota expiration value with traditional timestamps.
1213 * This corresponds exactly with the incore expiration Jan  1 00:00:01 UTC 1970.
1214 */
1215#define XFS_DQ_LEGACY_EXPIRY_MIN	((int64_t)1)
1216
1217/*
1218 * Largest possible ondisk quota expiration value with traditional timestamps.
1219 * This corresponds exactly with the incore expiration Feb  7 06:28:15 UTC 2106.
1220 */
1221#define XFS_DQ_LEGACY_EXPIRY_MAX	((int64_t)U32_MAX)
1222
1223/*
1224 * Smallest possible ondisk quota expiration value with bigtime timestamps.
1225 * This corresponds (after conversion to a Unix timestamp) with the incore
1226 * expiration of Jan  1 00:00:04 UTC 1970.
1227 */
1228#define XFS_DQ_BIGTIME_EXPIRY_MIN	(XFS_DQ_LEGACY_EXPIRY_MIN)
1229
1230/*
1231 * Largest supported ondisk quota expiration value with bigtime timestamps.
1232 * This corresponds (after conversion to a Unix timestamp) with an incore
1233 * expiration of Jul  2 20:20:24 UTC 2486.
1234 *
1235 * The ondisk field supports values up to -1U, which corresponds to an incore
1236 * expiration in 2514.  This is beyond the maximum the bigtime inode timestamp,
1237 * so we cap the maximum bigtime quota expiration to the max inode timestamp.
1238 */
1239#define XFS_DQ_BIGTIME_EXPIRY_MAX	((int64_t)4074815106U)
1240
1241/*
1242 * The following conversion factors assist in converting a quota expiration
1243 * timestamp between the incore and ondisk formats.
1244 */
1245#define XFS_DQ_BIGTIME_SHIFT	(2)
1246#define XFS_DQ_BIGTIME_SLACK	((int64_t)(1ULL << XFS_DQ_BIGTIME_SHIFT) - 1)
1247
1248/* Convert an incore quota expiration timestamp to an ondisk bigtime value. */
1249static inline uint32_t xfs_dq_unix_to_bigtime(time64_t unix_seconds)
1250{
1251	/*
1252	 * Round the expiration timestamp up to the nearest bigtime timestamp
1253	 * that we can store, to give users the most time to fix problems.
1254	 */
1255	return ((uint64_t)unix_seconds + XFS_DQ_BIGTIME_SLACK) >>
1256			XFS_DQ_BIGTIME_SHIFT;
1257}
1258
1259/* Convert an ondisk bigtime quota expiration value to an incore timestamp. */
1260static inline time64_t xfs_dq_bigtime_to_unix(uint32_t ondisk_seconds)
1261{
1262	return (time64_t)ondisk_seconds << XFS_DQ_BIGTIME_SHIFT;
1263}
1264
1265/*
1266 * Default quota grace periods, ranging from zero (use the compiled defaults)
1267 * to ~136 years.  These are applied to a non-root dquot that has exceeded
1268 * either limit.
1269 */
1270#define XFS_DQ_GRACE_MIN		((int64_t)0)
1271#define XFS_DQ_GRACE_MAX		((int64_t)U32_MAX)
 
 
 
1272
1273/*
1274 * This is the main portion of the on-disk representation of quota information
1275 * for a user.  We pad this with some more expansion room to construct the on
1276 * disk structure.
1277 */
1278struct xfs_disk_dquot {
1279	__be16		d_magic;	/* dquot magic = XFS_DQUOT_MAGIC */
1280	__u8		d_version;	/* dquot version */
1281	__u8		d_type;		/* XFS_DQTYPE_USER/PROJ/GROUP */
1282	__be32		d_id;		/* user,project,group id */
1283	__be64		d_blk_hardlimit;/* absolute limit on disk blks */
1284	__be64		d_blk_softlimit;/* preferred limit on disk blks */
1285	__be64		d_ino_hardlimit;/* maximum # allocated inodes */
1286	__be64		d_ino_softlimit;/* preferred inode limit */
1287	__be64		d_bcount;	/* disk blocks owned by the user */
1288	__be64		d_icount;	/* inodes owned by the user */
1289	__be32		d_itimer;	/* zero if within inode limits if not,
1290					   this is when we refuse service */
1291	__be32		d_btimer;	/* similar to above; for disk blocks */
1292	__be16		d_iwarns;	/* warnings issued wrt num inodes */
1293	__be16		d_bwarns;	/* warnings issued wrt disk blocks */
1294	__be32		d_pad0;		/* 64 bit align */
1295	__be64		d_rtb_hardlimit;/* absolute limit on realtime blks */
1296	__be64		d_rtb_softlimit;/* preferred limit on RT disk blks */
1297	__be64		d_rtbcount;	/* realtime blocks owned */
1298	__be32		d_rtbtimer;	/* similar to above; for RT disk blocks */
1299	__be16		d_rtbwarns;	/* warnings issued wrt RT disk blocks */
1300	__be16		d_pad;
1301};
1302
1303/*
1304 * This is what goes on disk. This is separated from the xfs_disk_dquot because
1305 * carrying the unnecessary padding would be a waste of memory.
1306 */
1307struct xfs_dqblk {
1308	struct xfs_disk_dquot	dd_diskdq; /* portion living incore as well */
1309	char			dd_fill[4];/* filling for posterity */
1310
1311	/*
1312	 * These two are only present on filesystems with the CRC bits set.
1313	 */
1314	__be32		  dd_crc;	/* checksum */
1315	__be64		  dd_lsn;	/* last modification in log */
1316	uuid_t		  dd_uuid;	/* location information */
1317};
1318
1319#define XFS_DQUOT_CRC_OFF	offsetof(struct xfs_dqblk, dd_crc)
1320
1321/*
1322 * This defines the unit of allocation of dquots.
1323 *
1324 * Currently, it is just one file system block, and a 4K blk contains 30
1325 * (136 * 30 = 4080) dquots. It's probably not worth trying to make
1326 * this more dynamic.
1327 *
1328 * However, if this number is changed, we have to make sure that we don't
1329 * implicitly assume that we do allocations in chunks of a single filesystem
1330 * block in the dquot/xqm code.
1331 *
1332 * This is part of the ondisk format because the structure size is not a power
1333 * of two, which leaves slack at the end of the disk block.
1334 */
1335#define XFS_DQUOT_CLUSTER_SIZE_FSB	(xfs_filblks_t)1
1336
1337/*
1338 * Remote symlink format and access functions.
1339 */
1340#define XFS_SYMLINK_MAGIC	0x58534c4d	/* XSLM */
1341
1342struct xfs_dsymlink_hdr {
1343	__be32	sl_magic;
1344	__be32	sl_offset;
1345	__be32	sl_bytes;
1346	__be32	sl_crc;
1347	uuid_t	sl_uuid;
1348	__be64	sl_owner;
1349	__be64	sl_blkno;
1350	__be64	sl_lsn;
1351};
1352
1353#define XFS_SYMLINK_CRC_OFF	offsetof(struct xfs_dsymlink_hdr, sl_crc)
1354
1355#define XFS_SYMLINK_MAXLEN	1024
1356/*
1357 * The maximum pathlen is 1024 bytes. Since the minimum file system
1358 * blocksize is 512 bytes, we can get a max of 3 extents back from
1359 * bmapi when crc headers are taken into account.
1360 */
1361#define XFS_SYMLINK_MAPS 3
1362
1363#define XFS_SYMLINK_BUF_SPACE(mp, bufsize)	\
1364	((bufsize) - (xfs_has_crc((mp)) ? \
1365			sizeof(struct xfs_dsymlink_hdr) : 0))
1366
1367
1368/*
1369 * Allocation Btree format definitions
1370 *
1371 * There are two on-disk btrees, one sorted by blockno and one sorted
1372 * by blockcount and blockno.  All blocks look the same to make the code
1373 * simpler; if we have time later, we'll make the optimizations.
1374 */
1375#define	XFS_ABTB_MAGIC		0x41425442	/* 'ABTB' for bno tree */
1376#define	XFS_ABTB_CRC_MAGIC	0x41423342	/* 'AB3B' */
1377#define	XFS_ABTC_MAGIC		0x41425443	/* 'ABTC' for cnt tree */
1378#define	XFS_ABTC_CRC_MAGIC	0x41423343	/* 'AB3C' */
1379
1380/*
1381 * Data record/key structure
1382 */
1383typedef struct xfs_alloc_rec {
1384	__be32		ar_startblock;	/* starting block number */
1385	__be32		ar_blockcount;	/* count of free blocks */
1386} xfs_alloc_rec_t, xfs_alloc_key_t;
1387
1388typedef struct xfs_alloc_rec_incore {
1389	xfs_agblock_t	ar_startblock;	/* starting block number */
1390	xfs_extlen_t	ar_blockcount;	/* count of free blocks */
1391} xfs_alloc_rec_incore_t;
1392
1393/* btree pointer type */
1394typedef __be32 xfs_alloc_ptr_t;
1395
1396/*
1397 * Block numbers in the AG:
1398 * SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3.
1399 */
1400#define	XFS_BNO_BLOCK(mp)	((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1))
1401#define	XFS_CNT_BLOCK(mp)	((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))
1402
1403
1404/*
1405 * Inode Allocation Btree format definitions
1406 *
1407 * There is a btree for the inode map per allocation group.
1408 */
1409#define	XFS_IBT_MAGIC		0x49414254	/* 'IABT' */
1410#define	XFS_IBT_CRC_MAGIC	0x49414233	/* 'IAB3' */
1411#define	XFS_FIBT_MAGIC		0x46494254	/* 'FIBT' */
1412#define	XFS_FIBT_CRC_MAGIC	0x46494233	/* 'FIB3' */
1413
1414typedef uint64_t	xfs_inofree_t;
1415#define	XFS_INODES_PER_CHUNK		(NBBY * sizeof(xfs_inofree_t))
1416#define	XFS_INODES_PER_CHUNK_LOG	(XFS_NBBYLOG + 3)
1417#define	XFS_INOBT_ALL_FREE		((xfs_inofree_t)-1)
1418#define	XFS_INOBT_MASK(i)		((xfs_inofree_t)1 << (i))
1419
1420#define XFS_INOBT_HOLEMASK_FULL		0	/* holemask for full chunk */
1421#define XFS_INOBT_HOLEMASK_BITS		(NBBY * sizeof(uint16_t))
1422#define XFS_INODES_PER_HOLEMASK_BIT	\
1423	(XFS_INODES_PER_CHUNK / (NBBY * sizeof(uint16_t)))
1424
1425static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
1426{
1427	return ((n >= XFS_INODES_PER_CHUNK ? 0 : XFS_INOBT_MASK(n)) - 1) << i;
1428}
1429
1430/*
1431 * The on-disk inode record structure has two formats. The original "full"
1432 * format uses a 4-byte freecount. The "sparse" format uses a 1-byte freecount
1433 * and replaces the 3 high-order freecount bytes wth the holemask and inode
1434 * count.
1435 *
1436 * The holemask of the sparse record format allows an inode chunk to have holes
1437 * that refer to blocks not owned by the inode record. This facilitates inode
1438 * allocation in the event of severe free space fragmentation.
1439 */
1440typedef struct xfs_inobt_rec {
1441	__be32		ir_startino;	/* starting inode number */
1442	union {
1443		struct {
1444			__be32	ir_freecount;	/* count of free inodes */
1445		} f;
1446		struct {
1447			__be16	ir_holemask;/* hole mask for sparse chunks */
1448			__u8	ir_count;	/* total inode count */
1449			__u8	ir_freecount;	/* count of free inodes */
1450		} sp;
1451	} ir_u;
1452	__be64		ir_free;	/* free inode mask */
1453} xfs_inobt_rec_t;
1454
1455typedef struct xfs_inobt_rec_incore {
1456	xfs_agino_t	ir_startino;	/* starting inode number */
1457	uint16_t	ir_holemask;	/* hole mask for sparse chunks */
1458	uint8_t		ir_count;	/* total inode count */
1459	uint8_t		ir_freecount;	/* count of free inodes (set bits) */
1460	xfs_inofree_t	ir_free;	/* free inode mask */
1461} xfs_inobt_rec_incore_t;
1462
1463static inline bool xfs_inobt_issparse(uint16_t holemask)
1464{
1465	/* non-zero holemask represents a sparse rec. */
1466	return holemask;
1467}
1468
1469/*
1470 * Key structure
1471 */
1472typedef struct xfs_inobt_key {
1473	__be32		ir_startino;	/* starting inode number */
1474} xfs_inobt_key_t;
1475
1476/* btree pointer type */
1477typedef __be32 xfs_inobt_ptr_t;
1478
1479/*
1480 * block numbers in the AG.
1481 */
1482#define	XFS_IBT_BLOCK(mp)		((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1))
1483#define	XFS_FIBT_BLOCK(mp)		((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))
1484
1485/*
1486 * Reverse mapping btree format definitions
1487 *
1488 * There is a btree for the reverse map per allocation group
1489 */
1490#define	XFS_RMAP_CRC_MAGIC	0x524d4233	/* 'RMB3' */
1491
1492/*
1493 * Ownership info for an extent.  This is used to create reverse-mapping
1494 * entries.
1495 */
1496#define XFS_OWNER_INFO_ATTR_FORK	(1 << 0)
1497#define XFS_OWNER_INFO_BMBT_BLOCK	(1 << 1)
1498struct xfs_owner_info {
1499	uint64_t		oi_owner;
1500	xfs_fileoff_t		oi_offset;
1501	unsigned int		oi_flags;
1502};
1503
1504/*
1505 * Special owner types.
1506 *
1507 * Seeing as we only support up to 8EB, we have the upper bit of the owner field
1508 * to tell us we have a special owner value. We use these for static metadata
1509 * allocated at mkfs/growfs time, as well as for freespace management metadata.
1510 */
1511#define XFS_RMAP_OWN_NULL	(-1ULL)	/* No owner, for growfs */
1512#define XFS_RMAP_OWN_UNKNOWN	(-2ULL)	/* Unknown owner, for EFI recovery */
1513#define XFS_RMAP_OWN_FS		(-3ULL)	/* static fs metadata */
1514#define XFS_RMAP_OWN_LOG	(-4ULL)	/* static fs metadata */
1515#define XFS_RMAP_OWN_AG		(-5ULL)	/* AG freespace btree blocks */
1516#define XFS_RMAP_OWN_INOBT	(-6ULL)	/* Inode btree blocks */
1517#define XFS_RMAP_OWN_INODES	(-7ULL)	/* Inode chunk */
1518#define XFS_RMAP_OWN_REFC	(-8ULL) /* refcount tree */
1519#define XFS_RMAP_OWN_COW	(-9ULL) /* cow allocations */
1520#define XFS_RMAP_OWN_MIN	(-10ULL) /* guard */
1521
1522#define XFS_RMAP_NON_INODE_OWNER(owner)	(!!((owner) & (1ULL << 63)))
1523
1524/*
1525 * Data record structure
1526 */
1527struct xfs_rmap_rec {
1528	__be32		rm_startblock;	/* extent start block */
1529	__be32		rm_blockcount;	/* extent length */
1530	__be64		rm_owner;	/* extent owner */
1531	__be64		rm_offset;	/* offset within the owner */
1532};
1533
1534/*
1535 * rmap btree record
1536 *  rm_offset:63 is the attribute fork flag
1537 *  rm_offset:62 is the bmbt block flag
1538 *  rm_offset:61 is the unwritten extent flag (same as l0:63 in bmbt)
1539 *  rm_offset:54-60 aren't used and should be zero
1540 *  rm_offset:0-53 is the block offset within the inode
1541 */
1542#define XFS_RMAP_OFF_ATTR_FORK	((uint64_t)1ULL << 63)
1543#define XFS_RMAP_OFF_BMBT_BLOCK	((uint64_t)1ULL << 62)
1544#define XFS_RMAP_OFF_UNWRITTEN	((uint64_t)1ULL << 61)
1545
1546#define XFS_RMAP_LEN_MAX	((uint32_t)~0U)
1547#define XFS_RMAP_OFF_FLAGS	(XFS_RMAP_OFF_ATTR_FORK | \
1548				 XFS_RMAP_OFF_BMBT_BLOCK | \
1549				 XFS_RMAP_OFF_UNWRITTEN)
1550#define XFS_RMAP_OFF_MASK	((uint64_t)0x3FFFFFFFFFFFFFULL)
1551
1552#define XFS_RMAP_OFF(off)		((off) & XFS_RMAP_OFF_MASK)
1553
1554#define XFS_RMAP_IS_BMBT_BLOCK(off)	(!!((off) & XFS_RMAP_OFF_BMBT_BLOCK))
1555#define XFS_RMAP_IS_ATTR_FORK(off)	(!!((off) & XFS_RMAP_OFF_ATTR_FORK))
1556#define XFS_RMAP_IS_UNWRITTEN(len)	(!!((off) & XFS_RMAP_OFF_UNWRITTEN))
1557
1558#define RMAPBT_STARTBLOCK_BITLEN	32
1559#define RMAPBT_BLOCKCOUNT_BITLEN	32
1560#define RMAPBT_OWNER_BITLEN		64
1561#define RMAPBT_ATTRFLAG_BITLEN		1
1562#define RMAPBT_BMBTFLAG_BITLEN		1
1563#define RMAPBT_EXNTFLAG_BITLEN		1
1564#define RMAPBT_UNUSED_OFFSET_BITLEN	7
1565#define RMAPBT_OFFSET_BITLEN		54
1566
1567/*
1568 * Key structure
1569 *
1570 * We don't use the length for lookups
1571 */
1572struct xfs_rmap_key {
1573	__be32		rm_startblock;	/* extent start block */
1574	__be64		rm_owner;	/* extent owner */
1575	__be64		rm_offset;	/* offset within the owner */
1576} __attribute__((packed));
1577
1578/* btree pointer type */
1579typedef __be32 xfs_rmap_ptr_t;
1580
1581#define	XFS_RMAP_BLOCK(mp) \
1582	(xfs_has_finobt(((mp))) ? \
1583	 XFS_FIBT_BLOCK(mp) + 1 : \
1584	 XFS_IBT_BLOCK(mp) + 1)
1585
1586/*
1587 * Reference Count Btree format definitions
1588 *
1589 */
1590#define	XFS_REFC_CRC_MAGIC	0x52334643	/* 'R3FC' */
1591
1592unsigned int xfs_refc_block(struct xfs_mount *mp);
1593
1594/*
1595 * Data record/key structure
1596 *
1597 * Each record associates a range of physical blocks (starting at
1598 * rc_startblock and ending rc_blockcount blocks later) with a reference
1599 * count (rc_refcount).  Extents that are being used to stage a copy on
1600 * write (CoW) operation are recorded in the refcount btree with a
1601 * refcount of 1.  All other records must have a refcount > 1 and must
1602 * track an extent mapped only by file data forks.
1603 *
1604 * Extents with a single owner (attributes, metadata, non-shared file
1605 * data) are not tracked here.  Free space is also not tracked here.
1606 * This is consistent with pre-reflink XFS.
1607 */
1608
1609/*
1610 * Extents that are being used to stage a copy on write are stored
1611 * in the refcount btree with a refcount of 1 and the upper bit set
1612 * on the startblock.  This speeds up mount time deletion of stale
1613 * staging extents because they're all at the right side of the tree.
1614 */
1615#define XFS_REFC_COWFLAG		(1U << 31)
1616#define REFCNTBT_COWFLAG_BITLEN		1
1617#define REFCNTBT_AGBLOCK_BITLEN		31
1618
1619struct xfs_refcount_rec {
1620	__be32		rc_startblock;	/* starting block number */
1621	__be32		rc_blockcount;	/* count of blocks */
1622	__be32		rc_refcount;	/* number of inodes linked here */
1623};
1624
1625struct xfs_refcount_key {
1626	__be32		rc_startblock;	/* starting block number */
1627};
1628
1629#define MAXREFCOUNT	((xfs_nlink_t)~0U)
1630#define MAXREFCEXTLEN	((xfs_extlen_t)~0U)
1631
1632/* btree pointer type */
1633typedef __be32 xfs_refcount_ptr_t;
1634
1635
1636/*
1637 * BMAP Btree format definitions
1638 *
1639 * This includes both the root block definition that sits inside an inode fork
1640 * and the record/pointer formats for the leaf/node in the blocks.
1641 */
1642#define XFS_BMAP_MAGIC		0x424d4150	/* 'BMAP' */
1643#define XFS_BMAP_CRC_MAGIC	0x424d4133	/* 'BMA3' */
1644
1645/*
1646 * Bmap root header, on-disk form only.
1647 */
1648typedef struct xfs_bmdr_block {
1649	__be16		bb_level;	/* 0 is a leaf */
1650	__be16		bb_numrecs;	/* current # of data records */
1651} xfs_bmdr_block_t;
1652
1653/*
1654 * Bmap btree record and extent descriptor.
1655 *  l0:63 is an extent flag (value 1 indicates non-normal).
1656 *  l0:9-62 are startoff.
1657 *  l0:0-8 and l1:21-63 are startblock.
1658 *  l1:0-20 are blockcount.
1659 */
1660#define BMBT_EXNTFLAG_BITLEN	1
1661#define BMBT_STARTOFF_BITLEN	54
1662#define BMBT_STARTBLOCK_BITLEN	52
1663#define BMBT_BLOCKCOUNT_BITLEN	21
1664
1665#define BMBT_STARTOFF_MASK	((1ULL << BMBT_STARTOFF_BITLEN) - 1)
1666#define BMBT_BLOCKCOUNT_MASK	((1ULL << BMBT_BLOCKCOUNT_BITLEN) - 1)
1667
1668#define XFS_MAX_BMBT_EXTLEN	((xfs_extlen_t)(BMBT_BLOCKCOUNT_MASK))
1669
1670/*
1671 * bmbt records have a file offset (block) field that is 54 bits wide, so this
1672 * is the largest xfs_fileoff_t that we ever expect to see.
1673 */
1674#define XFS_MAX_FILEOFF		(BMBT_STARTOFF_MASK + BMBT_BLOCKCOUNT_MASK)
1675
1676typedef struct xfs_bmbt_rec {
1677	__be64			l0, l1;
1678} xfs_bmbt_rec_t;
1679
1680typedef uint64_t	xfs_bmbt_rec_base_t;	/* use this for casts */
1681typedef xfs_bmbt_rec_t xfs_bmdr_rec_t;
1682
1683/*
1684 * Values and macros for delayed-allocation startblock fields.
1685 */
1686#define STARTBLOCKVALBITS	17
1687#define STARTBLOCKMASKBITS	(15 + 20)
1688#define STARTBLOCKMASK		\
1689	(((((xfs_fsblock_t)1) << STARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
1690
1691static inline int isnullstartblock(xfs_fsblock_t x)
1692{
1693	return ((x) & STARTBLOCKMASK) == STARTBLOCKMASK;
1694}
1695
1696static inline xfs_fsblock_t nullstartblock(int k)
1697{
1698	ASSERT(k < (1 << STARTBLOCKVALBITS));
1699	return STARTBLOCKMASK | (k);
1700}
1701
1702static inline xfs_filblks_t startblockval(xfs_fsblock_t x)
1703{
1704	return (xfs_filblks_t)((x) & ~STARTBLOCKMASK);
1705}
1706
1707/*
1708 * Key structure for non-leaf levels of the tree.
1709 */
1710typedef struct xfs_bmbt_key {
1711	__be64		br_startoff;	/* starting file offset */
1712} xfs_bmbt_key_t, xfs_bmdr_key_t;
1713
1714/* btree pointer type */
1715typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t;
1716
1717
1718/*
1719 * Generic Btree block format definitions
1720 *
1721 * This is a combination of the actual format used on disk for short and long
1722 * format btrees.  The first three fields are shared by both format, but the
1723 * pointers are different and should be used with care.
1724 *
1725 * To get the size of the actual short or long form headers please use the size
1726 * macros below.  Never use sizeof(xfs_btree_block).
1727 *
1728 * The blkno, crc, lsn, owner and uuid fields are only available in filesystems
1729 * with the crc feature bit, and all accesses to them must be conditional on
1730 * that flag.
1731 */
1732/* short form block header */
1733struct xfs_btree_block_shdr {
1734	__be32		bb_leftsib;
1735	__be32		bb_rightsib;
1736
1737	__be64		bb_blkno;
1738	__be64		bb_lsn;
1739	uuid_t		bb_uuid;
1740	__be32		bb_owner;
1741	__le32		bb_crc;
1742};
1743
1744/* long form block header */
1745struct xfs_btree_block_lhdr {
1746	__be64		bb_leftsib;
1747	__be64		bb_rightsib;
1748
1749	__be64		bb_blkno;
1750	__be64		bb_lsn;
1751	uuid_t		bb_uuid;
1752	__be64		bb_owner;
1753	__le32		bb_crc;
1754	__be32		bb_pad; /* padding for alignment */
1755};
1756
1757struct xfs_btree_block {
1758	__be32		bb_magic;	/* magic number for block type */
1759	__be16		bb_level;	/* 0 is a leaf */
1760	__be16		bb_numrecs;	/* current # of data records */
1761	union {
1762		struct xfs_btree_block_shdr s;
1763		struct xfs_btree_block_lhdr l;
1764	} bb_u;				/* rest */
1765};
1766
1767/* size of a short form block */
1768#define XFS_BTREE_SBLOCK_LEN \
1769	(offsetof(struct xfs_btree_block, bb_u) + \
1770	 offsetof(struct xfs_btree_block_shdr, bb_blkno))
1771/* size of a long form block */
1772#define XFS_BTREE_LBLOCK_LEN \
1773	(offsetof(struct xfs_btree_block, bb_u) + \
1774	 offsetof(struct xfs_btree_block_lhdr, bb_blkno))
1775
1776/* sizes of CRC enabled btree blocks */
1777#define XFS_BTREE_SBLOCK_CRC_LEN \
1778	(offsetof(struct xfs_btree_block, bb_u) + \
1779	 sizeof(struct xfs_btree_block_shdr))
1780#define XFS_BTREE_LBLOCK_CRC_LEN \
1781	(offsetof(struct xfs_btree_block, bb_u) + \
1782	 sizeof(struct xfs_btree_block_lhdr))
1783
1784#define XFS_BTREE_SBLOCK_CRC_OFF \
1785	offsetof(struct xfs_btree_block, bb_u.s.bb_crc)
1786#define XFS_BTREE_LBLOCK_CRC_OFF \
1787	offsetof(struct xfs_btree_block, bb_u.l.bb_crc)
1788
1789/*
1790 * On-disk XFS access control list structure.
1791 */
1792struct xfs_acl_entry {
1793	__be32	ae_tag;
1794	__be32	ae_id;
1795	__be16	ae_perm;
1796	__be16	ae_pad;		/* fill the implicit hole in the structure */
1797};
1798
1799struct xfs_acl {
1800	__be32			acl_cnt;
1801	struct xfs_acl_entry	acl_entry[];
1802};
1803
1804/*
1805 * The number of ACL entries allowed is defined by the on-disk format.
1806 * For v4 superblocks, that is limited to 25 entries. For v5 superblocks, it is
1807 * limited only by the maximum size of the xattr that stores the information.
1808 */
1809#define XFS_ACL_MAX_ENTRIES(mp)	\
1810	(xfs_has_crc(mp) \
1811		?  (XFS_XATTR_SIZE_MAX - sizeof(struct xfs_acl)) / \
1812						sizeof(struct xfs_acl_entry) \
1813		: 25)
1814
1815#define XFS_ACL_SIZE(cnt) \
1816	(sizeof(struct xfs_acl) + \
1817		sizeof(struct xfs_acl_entry) * cnt)
1818
1819#define XFS_ACL_MAX_SIZE(mp) \
1820	XFS_ACL_SIZE(XFS_ACL_MAX_ENTRIES((mp)))
1821
1822
1823/* On-disk XFS extended attribute names */
1824#define SGI_ACL_FILE		"SGI_ACL_FILE"
1825#define SGI_ACL_DEFAULT		"SGI_ACL_DEFAULT"
1826#define SGI_ACL_FILE_SIZE	(sizeof(SGI_ACL_FILE)-1)
1827#define SGI_ACL_DEFAULT_SIZE	(sizeof(SGI_ACL_DEFAULT)-1)
1828
1829#endif /* __XFS_FORMAT_H__ */
v6.13.7
   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   4 * All Rights Reserved.
   5 */
   6#ifndef __XFS_FORMAT_H__
   7#define __XFS_FORMAT_H__
   8
   9/*
  10 * XFS On Disk Format Definitions
  11 *
  12 * This header file defines all the on-disk format definitions for
  13 * general XFS objects. Directory and attribute related objects are defined in
  14 * xfs_da_format.h, which log and log item formats are defined in
  15 * xfs_log_format.h. Everything else goes here.
  16 */
  17
  18struct xfs_mount;
  19struct xfs_trans;
  20struct xfs_inode;
  21struct xfs_buf;
  22struct xfs_ifork;
  23
  24/*
  25 * Super block
  26 * Fits into a sector-sized buffer at address 0 of each allocation group.
  27 * Only the first of these is ever updated except during growfs.
  28 */
  29#define	XFS_SB_MAGIC		0x58465342	/* 'XFSB' */
  30#define	XFS_SB_VERSION_1	1		/* 5.3, 6.0.1, 6.1 */
  31#define	XFS_SB_VERSION_2	2		/* 6.2 - attributes */
  32#define	XFS_SB_VERSION_3	3		/* 6.2 - new inode version */
  33#define	XFS_SB_VERSION_4	4		/* 6.2+ - bitmask version */
  34#define	XFS_SB_VERSION_5	5		/* CRC enabled filesystem */
  35#define	XFS_SB_VERSION_NUMBITS		0x000f
  36#define	XFS_SB_VERSION_ALLFBITS		0xfff0
  37#define	XFS_SB_VERSION_ATTRBIT		0x0010
  38#define	XFS_SB_VERSION_NLINKBIT		0x0020
  39#define	XFS_SB_VERSION_QUOTABIT		0x0040
  40#define	XFS_SB_VERSION_ALIGNBIT		0x0080
  41#define	XFS_SB_VERSION_DALIGNBIT	0x0100
  42#define	XFS_SB_VERSION_SHAREDBIT	0x0200
  43#define XFS_SB_VERSION_LOGV2BIT		0x0400
  44#define XFS_SB_VERSION_SECTORBIT	0x0800
  45#define	XFS_SB_VERSION_EXTFLGBIT	0x1000
  46#define	XFS_SB_VERSION_DIRV2BIT		0x2000
  47#define	XFS_SB_VERSION_BORGBIT		0x4000	/* ASCII only case-insens. */
  48#define	XFS_SB_VERSION_MOREBITSBIT	0x8000
  49
  50/*
  51 * The size of a single extended attribute on disk is limited by
  52 * the size of index values within the attribute entries themselves.
  53 * These are be16 fields, so we can only support attribute data
  54 * sizes up to 2^16 bytes in length.
  55 */
  56#define XFS_XATTR_SIZE_MAX (1 << 16)
  57
  58/*
  59 * Supported feature bit list is just all bits in the versionnum field because
  60 * we've used them all up and understand them all. Except, of course, for the
  61 * shared superblock bit, which nobody knows what it does and so is unsupported.
  62 */
  63#define	XFS_SB_VERSION_OKBITS		\
  64	((XFS_SB_VERSION_NUMBITS | XFS_SB_VERSION_ALLFBITS) & \
  65		~XFS_SB_VERSION_SHAREDBIT)
  66
  67/*
  68 * There are two words to hold XFS "feature" bits: the original
  69 * word, sb_versionnum, and sb_features2.  Whenever a bit is set in
  70 * sb_features2, the feature bit XFS_SB_VERSION_MOREBITSBIT must be set.
  71 *
  72 * These defines represent bits in sb_features2.
  73 */
  74#define XFS_SB_VERSION2_RESERVED1BIT	0x00000001
  75#define XFS_SB_VERSION2_LAZYSBCOUNTBIT	0x00000002	/* Superblk counters */
  76#define XFS_SB_VERSION2_RESERVED4BIT	0x00000004
  77#define XFS_SB_VERSION2_ATTR2BIT	0x00000008	/* Inline attr rework */
  78#define XFS_SB_VERSION2_PARENTBIT	0x00000010	/* parent pointers */
  79#define XFS_SB_VERSION2_PROJID32BIT	0x00000080	/* 32 bit project id */
  80#define XFS_SB_VERSION2_CRCBIT		0x00000100	/* metadata CRCs */
  81#define XFS_SB_VERSION2_FTYPE		0x00000200	/* inode type in dir */
  82
  83#define	XFS_SB_VERSION2_OKBITS		\
  84	(XFS_SB_VERSION2_LAZYSBCOUNTBIT	| \
  85	 XFS_SB_VERSION2_ATTR2BIT	| \
  86	 XFS_SB_VERSION2_PROJID32BIT	| \
  87	 XFS_SB_VERSION2_FTYPE)
  88
  89/* Maximum size of the xfs filesystem label, no terminating NULL */
  90#define XFSLABEL_MAX			12
  91
  92/*
  93 * Superblock - in core version.  Must be padded to 64 bit alignment.
 
  94 */
  95typedef struct xfs_sb {
  96	uint32_t	sb_magicnum;	/* magic number == XFS_SB_MAGIC */
  97	uint32_t	sb_blocksize;	/* logical block size, bytes */
  98	xfs_rfsblock_t	sb_dblocks;	/* number of data blocks */
  99	xfs_rfsblock_t	sb_rblocks;	/* number of realtime blocks */
 100	xfs_rtbxlen_t	sb_rextents;	/* number of realtime extents */
 101	uuid_t		sb_uuid;	/* user-visible file system unique id */
 102	xfs_fsblock_t	sb_logstart;	/* starting block of log if internal */
 103	xfs_ino_t	sb_rootino;	/* root inode number */
 104	xfs_ino_t	sb_rbmino;	/* bitmap inode for realtime extents */
 105	xfs_ino_t	sb_rsumino;	/* summary inode for rt bitmap */
 106	xfs_agblock_t	sb_rextsize;	/* realtime extent size, blocks */
 107	xfs_agblock_t	sb_agblocks;	/* size of an allocation group */
 108	xfs_agnumber_t	sb_agcount;	/* number of allocation groups */
 109	xfs_extlen_t	sb_rbmblocks;	/* number of rt bitmap blocks */
 110	xfs_extlen_t	sb_logblocks;	/* number of log blocks */
 111	uint16_t	sb_versionnum;	/* header version == XFS_SB_VERSION */
 112	uint16_t	sb_sectsize;	/* volume sector size, bytes */
 113	uint16_t	sb_inodesize;	/* inode size, bytes */
 114	uint16_t	sb_inopblock;	/* inodes per block */
 115	char		sb_fname[XFSLABEL_MAX]; /* file system name */
 116	uint8_t		sb_blocklog;	/* log2 of sb_blocksize */
 117	uint8_t		sb_sectlog;	/* log2 of sb_sectsize */
 118	uint8_t		sb_inodelog;	/* log2 of sb_inodesize */
 119	uint8_t		sb_inopblog;	/* log2 of sb_inopblock */
 120	uint8_t		sb_agblklog;	/* log2 of sb_agblocks (rounded up) */
 121	uint8_t		sb_rextslog;	/* log2 of sb_rextents */
 122	uint8_t		sb_inprogress;	/* mkfs is in progress, don't mount */
 123	uint8_t		sb_imax_pct;	/* max % of fs for inode space */
 124					/* statistics */
 125	/*
 126	 * These fields must remain contiguous.  If you really
 127	 * want to change their layout, make sure you fix the
 128	 * code in xfs_trans_apply_sb_deltas().
 129	 */
 130	uint64_t	sb_icount;	/* allocated inodes */
 131	uint64_t	sb_ifree;	/* free inodes */
 132	uint64_t	sb_fdblocks;	/* free data blocks */
 133	uint64_t	sb_frextents;	/* free realtime extents */
 134	/*
 135	 * End contiguous fields.
 136	 */
 137	xfs_ino_t	sb_uquotino;	/* user quota inode */
 138	xfs_ino_t	sb_gquotino;	/* group quota inode */
 139	uint16_t	sb_qflags;	/* quota flags */
 140	uint8_t		sb_flags;	/* misc. flags */
 141	uint8_t		sb_shared_vn;	/* shared version number */
 142	xfs_extlen_t	sb_inoalignmt;	/* inode chunk alignment, fsblocks */
 143	uint32_t	sb_unit;	/* stripe or raid unit */
 144	uint32_t	sb_width;	/* stripe or raid width */
 145	uint8_t		sb_dirblklog;	/* log2 of dir block size (fsbs) */
 146	uint8_t		sb_logsectlog;	/* log2 of the log sector size */
 147	uint16_t	sb_logsectsize;	/* sector size for the log, bytes */
 148	uint32_t	sb_logsunit;	/* stripe unit size for the log */
 149	uint32_t	sb_features2;	/* additional feature bits */
 150
 151	/*
 152	 * bad features2 field as a result of failing to pad the sb structure to
 153	 * 64 bits. Some machines will be using this field for features2 bits.
 154	 * Easiest just to mark it bad and not use it for anything else.
 155	 *
 156	 * This is not kept up to date in memory; it is always overwritten by
 157	 * the value in sb_features2 when formatting the incore superblock to
 158	 * the disk buffer.
 159	 */
 160	uint32_t	sb_bad_features2;
 161
 162	/* version 5 superblock fields start here */
 163
 164	/* feature masks */
 165	uint32_t	sb_features_compat;
 166	uint32_t	sb_features_ro_compat;
 167	uint32_t	sb_features_incompat;
 168	uint32_t	sb_features_log_incompat;
 169
 170	uint32_t	sb_crc;		/* superblock crc */
 171	xfs_extlen_t	sb_spino_align;	/* sparse inode chunk alignment */
 172
 173	xfs_ino_t	sb_pquotino;	/* project quota inode */
 174	xfs_lsn_t	sb_lsn;		/* last write sequence */
 175	uuid_t		sb_meta_uuid;	/* metadata file system unique id */
 176
 177	xfs_ino_t	sb_metadirino;	/* metadata directory tree root */
 178
 179	xfs_rgnumber_t	sb_rgcount;	/* number of realtime groups */
 180	xfs_rtxlen_t	sb_rgextents;	/* size of a realtime group in rtx */
 181
 182	uint8_t		sb_rgblklog;    /* rt group number shift */
 183	uint8_t		sb_pad[7];	/* zeroes */
 184
 185	/* must be padded to 64 bit alignment */
 186} xfs_sb_t;
 187
 
 
 188/*
 189 * Superblock - on disk version.
 190 * Must be padded to 64 bit alignment.
 191 */
 192struct xfs_dsb {
 193	__be32		sb_magicnum;	/* magic number == XFS_SB_MAGIC */
 194	__be32		sb_blocksize;	/* logical block size, bytes */
 195	__be64		sb_dblocks;	/* number of data blocks */
 196	__be64		sb_rblocks;	/* number of realtime blocks */
 197	__be64		sb_rextents;	/* number of realtime extents */
 198	uuid_t		sb_uuid;	/* user-visible file system unique id */
 199	__be64		sb_logstart;	/* starting block of log if internal */
 200	__be64		sb_rootino;	/* root inode number */
 201	__be64		sb_rbmino;	/* bitmap inode for realtime extents */
 202	__be64		sb_rsumino;	/* summary inode for rt bitmap */
 203	__be32		sb_rextsize;	/* realtime extent size, blocks */
 204	__be32		sb_agblocks;	/* size of an allocation group */
 205	__be32		sb_agcount;	/* number of allocation groups */
 206	__be32		sb_rbmblocks;	/* number of rt bitmap blocks */
 207	__be32		sb_logblocks;	/* number of log blocks */
 208	__be16		sb_versionnum;	/* header version == XFS_SB_VERSION */
 209	__be16		sb_sectsize;	/* volume sector size, bytes */
 210	__be16		sb_inodesize;	/* inode size, bytes */
 211	__be16		sb_inopblock;	/* inodes per block */
 212	char		sb_fname[XFSLABEL_MAX]; /* file system name */
 213	__u8		sb_blocklog;	/* log2 of sb_blocksize */
 214	__u8		sb_sectlog;	/* log2 of sb_sectsize */
 215	__u8		sb_inodelog;	/* log2 of sb_inodesize */
 216	__u8		sb_inopblog;	/* log2 of sb_inopblock */
 217	__u8		sb_agblklog;	/* log2 of sb_agblocks (rounded up) */
 218	__u8		sb_rextslog;	/* log2 of sb_rextents */
 219	__u8		sb_inprogress;	/* mkfs is in progress, don't mount */
 220	__u8		sb_imax_pct;	/* max % of fs for inode space */
 221					/* statistics */
 222	/*
 223	 * These fields must remain contiguous.  If you really
 224	 * want to change their layout, make sure you fix the
 225	 * code in xfs_trans_apply_sb_deltas().
 226	 */
 227	__be64		sb_icount;	/* allocated inodes */
 228	__be64		sb_ifree;	/* free inodes */
 229	__be64		sb_fdblocks;	/* free data blocks */
 230	__be64		sb_frextents;	/* free realtime extents */
 231	/*
 232	 * End contiguous fields.
 233	 */
 234	__be64		sb_uquotino;	/* user quota inode */
 235	__be64		sb_gquotino;	/* group quota inode */
 236	__be16		sb_qflags;	/* quota flags */
 237	__u8		sb_flags;	/* misc. flags */
 238	__u8		sb_shared_vn;	/* shared version number */
 239	__be32		sb_inoalignmt;	/* inode chunk alignment, fsblocks */
 240	__be32		sb_unit;	/* stripe or raid unit */
 241	__be32		sb_width;	/* stripe or raid width */
 242	__u8		sb_dirblklog;	/* log2 of dir block size (fsbs) */
 243	__u8		sb_logsectlog;	/* log2 of the log sector size */
 244	__be16		sb_logsectsize;	/* sector size for the log, bytes */
 245	__be32		sb_logsunit;	/* stripe unit size for the log */
 246	__be32		sb_features2;	/* additional feature bits */
 247	/*
 248	 * bad features2 field as a result of failing to pad the sb
 249	 * structure to 64 bits. Some machines will be using this field
 250	 * for features2 bits. Easiest just to mark it bad and not use
 251	 * it for anything else.
 252	 */
 253	__be32		sb_bad_features2;
 254
 255	/* version 5 superblock fields start here */
 256
 257	/* feature masks */
 258	__be32		sb_features_compat;
 259	__be32		sb_features_ro_compat;
 260	__be32		sb_features_incompat;
 261	__be32		sb_features_log_incompat;
 262
 263	__le32		sb_crc;		/* superblock crc */
 264	__be32		sb_spino_align;	/* sparse inode chunk alignment */
 265
 266	__be64		sb_pquotino;	/* project quota inode */
 267	__be64		sb_lsn;		/* last write sequence */
 268	uuid_t		sb_meta_uuid;	/* metadata file system unique id */
 269
 270	__be64		sb_metadirino;	/* metadata directory tree root */
 271	__be32		sb_rgcount;	/* # of realtime groups */
 272	__be32		sb_rgextents;	/* size of rtgroup in rtx */
 273
 274	__u8		sb_rgblklog;    /* rt group number shift */
 275	__u8		sb_pad[7];	/* zeroes */
 276
 277	/*
 278	 * The size of this structure must be padded to 64 bit alignment.
 279	 *
 280	 * NOTE: Don't forget to update secondary_sb_whack in xfs_repair when
 281	 * adding new fields here.
 282	 */
 283};
 284
 285#define XFS_SB_CRC_OFF		offsetof(struct xfs_dsb, sb_crc)
 286
 287/*
 288 * Misc. Flags - warning - these will be cleared by xfs_repair unless
 289 * a feature bit is set when the flag is used.
 290 */
 291#define XFS_SBF_NOFLAGS		0x00	/* no flags set */
 292#define XFS_SBF_READONLY	0x01	/* only read-only mounts allowed */
 293
 294/*
 295 * define max. shared version we can interoperate with
 296 */
 297#define XFS_SB_MAX_SHARED_VN	0
 298
 299#define	XFS_SB_VERSION_NUM(sbp)	((sbp)->sb_versionnum & XFS_SB_VERSION_NUMBITS)
 300
 301static inline bool xfs_sb_is_v5(const struct xfs_sb *sbp)
 302{
 303	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5;
 304}
 305
 306/*
 307 * Detect a mismatched features2 field.  Older kernels read/wrote
 308 * this into the wrong slot, so to be safe we keep them in sync.
 309 */
 310static inline bool xfs_sb_has_mismatched_features2(const struct xfs_sb *sbp)
 311{
 312	return sbp->sb_bad_features2 != sbp->sb_features2;
 313}
 314
 315static inline bool xfs_sb_version_hasmorebits(const struct xfs_sb *sbp)
 316{
 317	return xfs_sb_is_v5(sbp) ||
 318	       (sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT);
 319}
 320
 321static inline void xfs_sb_version_addattr(struct xfs_sb *sbp)
 322{
 323	sbp->sb_versionnum |= XFS_SB_VERSION_ATTRBIT;
 324}
 325
 326static inline void xfs_sb_version_addquota(struct xfs_sb *sbp)
 327{
 328	sbp->sb_versionnum |= XFS_SB_VERSION_QUOTABIT;
 329}
 330
 331static inline void xfs_sb_version_addattr2(struct xfs_sb *sbp)
 332{
 333	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
 334	sbp->sb_features2 |= XFS_SB_VERSION2_ATTR2BIT;
 335}
 336
 337static inline void xfs_sb_version_addprojid32(struct xfs_sb *sbp)
 338{
 339	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
 340	sbp->sb_features2 |= XFS_SB_VERSION2_PROJID32BIT;
 341}
 342
 343/*
 344 * Extended v5 superblock feature masks. These are to be used for new v5
 345 * superblock features only.
 346 *
 347 * Compat features are new features that old kernels will not notice or affect
 348 * and so can mount read-write without issues.
 349 *
 350 * RO-Compat (read only) are features that old kernels can read but will break
 351 * if they write. Hence only read-only mounts of such filesystems are allowed on
 352 * kernels that don't support the feature bit.
 353 *
 354 * InCompat features are features which old kernels will not understand and so
 355 * must not mount.
 356 *
 357 * Log-InCompat features are for changes to log formats or new transactions that
 358 * can't be replayed on older kernels. The fields are set when the filesystem is
 359 * mounted, and a clean unmount clears the fields.
 360 */
 361#define XFS_SB_FEAT_COMPAT_ALL 0
 362#define XFS_SB_FEAT_COMPAT_UNKNOWN	~XFS_SB_FEAT_COMPAT_ALL
 363static inline bool
 364xfs_sb_has_compat_feature(
 365	const struct xfs_sb	*sbp,
 366	uint32_t		feature)
 367{
 368	return (sbp->sb_features_compat & feature) != 0;
 369}
 370
 371#define XFS_SB_FEAT_RO_COMPAT_FINOBT   (1 << 0)		/* free inode btree */
 372#define XFS_SB_FEAT_RO_COMPAT_RMAPBT   (1 << 1)		/* reverse map btree */
 373#define XFS_SB_FEAT_RO_COMPAT_REFLINK  (1 << 2)		/* reflinked files */
 374#define XFS_SB_FEAT_RO_COMPAT_INOBTCNT (1 << 3)		/* inobt block counts */
 375#define XFS_SB_FEAT_RO_COMPAT_ALL \
 376		(XFS_SB_FEAT_RO_COMPAT_FINOBT | \
 377		 XFS_SB_FEAT_RO_COMPAT_RMAPBT | \
 378		 XFS_SB_FEAT_RO_COMPAT_REFLINK| \
 379		 XFS_SB_FEAT_RO_COMPAT_INOBTCNT)
 380#define XFS_SB_FEAT_RO_COMPAT_UNKNOWN	~XFS_SB_FEAT_RO_COMPAT_ALL
 381static inline bool
 382xfs_sb_has_ro_compat_feature(
 383	const struct xfs_sb	*sbp,
 384	uint32_t		feature)
 385{
 386	return (sbp->sb_features_ro_compat & feature) != 0;
 387}
 388
 389#define XFS_SB_FEAT_INCOMPAT_FTYPE	(1 << 0)  /* filetype in dirent */
 390#define XFS_SB_FEAT_INCOMPAT_SPINODES	(1 << 1)  /* sparse inode chunks */
 391#define XFS_SB_FEAT_INCOMPAT_META_UUID	(1 << 2)  /* metadata UUID */
 392#define XFS_SB_FEAT_INCOMPAT_BIGTIME	(1 << 3)  /* large timestamps */
 393#define XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR (1 << 4) /* needs xfs_repair */
 394#define XFS_SB_FEAT_INCOMPAT_NREXT64	(1 << 5)  /* large extent counters */
 395#define XFS_SB_FEAT_INCOMPAT_EXCHRANGE	(1 << 6)  /* exchangerange supported */
 396#define XFS_SB_FEAT_INCOMPAT_PARENT	(1 << 7)  /* parent pointers */
 397#define XFS_SB_FEAT_INCOMPAT_METADIR	(1 << 8)  /* metadata dir tree */
 398#define XFS_SB_FEAT_INCOMPAT_ALL \
 399		(XFS_SB_FEAT_INCOMPAT_FTYPE | \
 400		 XFS_SB_FEAT_INCOMPAT_SPINODES | \
 401		 XFS_SB_FEAT_INCOMPAT_META_UUID | \
 402		 XFS_SB_FEAT_INCOMPAT_BIGTIME | \
 403		 XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR | \
 404		 XFS_SB_FEAT_INCOMPAT_NREXT64 | \
 405		 XFS_SB_FEAT_INCOMPAT_EXCHRANGE | \
 406		 XFS_SB_FEAT_INCOMPAT_PARENT | \
 407		 XFS_SB_FEAT_INCOMPAT_METADIR)
 408
 409#define XFS_SB_FEAT_INCOMPAT_UNKNOWN	~XFS_SB_FEAT_INCOMPAT_ALL
 410static inline bool
 411xfs_sb_has_incompat_feature(
 412	const struct xfs_sb	*sbp,
 413	uint32_t		feature)
 414{
 415	return (sbp->sb_features_incompat & feature) != 0;
 416}
 417
 418#define XFS_SB_FEAT_INCOMPAT_LOG_XATTRS   (1 << 0)	/* Delayed Attributes */
 419#define XFS_SB_FEAT_INCOMPAT_LOG_ALL \
 420	(XFS_SB_FEAT_INCOMPAT_LOG_XATTRS)
 421#define XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN	~XFS_SB_FEAT_INCOMPAT_LOG_ALL
 422static inline bool
 423xfs_sb_has_incompat_log_feature(
 424	const struct xfs_sb	*sbp,
 425	uint32_t		feature)
 426{
 427	return (sbp->sb_features_log_incompat & feature) != 0;
 428}
 429
 430static inline void
 431xfs_sb_remove_incompat_log_features(
 432	struct xfs_sb	*sbp)
 433{
 434	sbp->sb_features_log_incompat &= ~XFS_SB_FEAT_INCOMPAT_LOG_ALL;
 435}
 436
 437static inline void
 438xfs_sb_add_incompat_log_features(
 439	struct xfs_sb	*sbp,
 440	unsigned int	features)
 441{
 442	sbp->sb_features_log_incompat |= features;
 443}
 444
 445static inline bool xfs_sb_version_haslogxattrs(const struct xfs_sb *sbp)
 446{
 447	return xfs_sb_is_v5(sbp) && (sbp->sb_features_log_incompat &
 448		 XFS_SB_FEAT_INCOMPAT_LOG_XATTRS);
 449}
 450
 451static inline bool
 452xfs_is_quota_inode(struct xfs_sb *sbp, xfs_ino_t ino)
 453{
 454	return (ino == sbp->sb_uquotino ||
 455		ino == sbp->sb_gquotino ||
 456		ino == sbp->sb_pquotino);
 457}
 458
 459#define XFS_SB_DADDR		((xfs_daddr_t)0) /* daddr in filesystem/ag */
 460#define	XFS_SB_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_SB_DADDR)
 461
 462#define	XFS_HDR_BLOCK(mp,d)	((xfs_agblock_t)XFS_BB_TO_FSBT(mp,d))
 463#define	XFS_DADDR_TO_FSB(mp,d)	XFS_AGB_TO_FSB(mp, \
 464			xfs_daddr_to_agno(mp,d), xfs_daddr_to_agbno(mp,d))
 465#define	XFS_FSB_TO_DADDR(mp,fsbno)	XFS_AGB_TO_DADDR(mp, \
 466			XFS_FSB_TO_AGNO(mp,fsbno), XFS_FSB_TO_AGBNO(mp,fsbno))
 467
 468/*
 469 * File system sector to basic block conversions.
 470 */
 471#define XFS_FSS_TO_BB(mp,sec)	((sec) << (mp)->m_sectbb_log)
 472
 473/*
 474 * File system block to basic block conversions.
 475 */
 476#define	XFS_FSB_TO_BB(mp,fsbno)	((fsbno) << (mp)->m_blkbb_log)
 477#define	XFS_BB_TO_FSB(mp,bb)	\
 478	(((bb) + (XFS_FSB_TO_BB(mp,1) - 1)) >> (mp)->m_blkbb_log)
 479#define	XFS_BB_TO_FSBT(mp,bb)	((bb) >> (mp)->m_blkbb_log)
 480
 481/*
 482 * File system block to byte conversions.
 483 */
 484#define XFS_FSB_TO_B(mp,fsbno)	((xfs_fsize_t)(fsbno) << (mp)->m_sb.sb_blocklog)
 485#define XFS_B_TO_FSB(mp,b)	\
 486	((((uint64_t)(b)) + (mp)->m_blockmask) >> (mp)->m_sb.sb_blocklog)
 487#define XFS_B_TO_FSBT(mp,b)	(((uint64_t)(b)) >> (mp)->m_sb.sb_blocklog)
 488
 489/*
 490 * Allocation group header
 491 *
 492 * This is divided into three structures, placed in sequential 512-byte
 493 * buffers after a copy of the superblock (also in a 512-byte buffer).
 494 */
 495#define	XFS_AGF_MAGIC	0x58414746	/* 'XAGF' */
 496#define	XFS_AGI_MAGIC	0x58414749	/* 'XAGI' */
 497#define	XFS_AGFL_MAGIC	0x5841464c	/* 'XAFL' */
 498#define	XFS_AGF_VERSION	1
 499#define	XFS_AGI_VERSION	1
 500
 501#define	XFS_AGF_GOOD_VERSION(v)	((v) == XFS_AGF_VERSION)
 502#define	XFS_AGI_GOOD_VERSION(v)	((v) == XFS_AGI_VERSION)
 503
 504/*
 505 * agf_cnt_level in the first AGF overlaps the EFS superblock's magic number.
 506 * Since the magic numbers valid for EFS are > 64k, our value cannot be confused
 507 * for an EFS superblock.
 
 
 
 
 
 
 508 */
 509
 510typedef struct xfs_agf {
 511	/*
 512	 * Common allocation group header information
 513	 */
 514	__be32		agf_magicnum;	/* magic number == XFS_AGF_MAGIC */
 515	__be32		agf_versionnum;	/* header version == XFS_AGF_VERSION */
 516	__be32		agf_seqno;	/* sequence # starting from 0 */
 517	__be32		agf_length;	/* size in blocks of a.g. */
 518	/*
 519	 * Freespace and rmap information
 520	 */
 521	__be32		agf_bno_root;	/* bnobt root block */
 522	__be32		agf_cnt_root;	/* cntbt root block */
 523	__be32		agf_rmap_root;	/* rmapbt root block */
 524
 525	__be32		agf_bno_level;	/* bnobt btree levels */
 526	__be32		agf_cnt_level;	/* cntbt btree levels */
 527	__be32		agf_rmap_level;	/* rmapbt btree levels */
 528
 529	__be32		agf_flfirst;	/* first freelist block's index */
 530	__be32		agf_fllast;	/* last freelist block's index */
 531	__be32		agf_flcount;	/* count of blocks in freelist */
 532	__be32		agf_freeblks;	/* total free blocks */
 533
 534	__be32		agf_longest;	/* longest free space */
 535	__be32		agf_btreeblks;	/* # of blocks held in AGF btrees */
 536	uuid_t		agf_uuid;	/* uuid of filesystem */
 537
 538	__be32		agf_rmap_blocks;	/* rmapbt blocks used */
 539	__be32		agf_refcount_blocks;	/* refcountbt blocks used */
 540
 541	__be32		agf_refcount_root;	/* refcount tree root block */
 542	__be32		agf_refcount_level;	/* refcount btree levels */
 543
 544	/*
 545	 * reserve some contiguous space for future logged fields before we add
 546	 * the unlogged fields. This makes the range logging via flags and
 547	 * structure offsets much simpler.
 548	 */
 549	__be64		agf_spare64[14];
 550
 551	/* unlogged fields, written during buffer writeback. */
 552	__be64		agf_lsn;	/* last write sequence */
 553	__be32		agf_crc;	/* crc of agf sector */
 554	__be32		agf_spare2;
 555
 556	/* structure must be padded to 64 bit alignment */
 557} xfs_agf_t;
 558
 559#define XFS_AGF_CRC_OFF		offsetof(struct xfs_agf, agf_crc)
 560
 561#define	XFS_AGF_MAGICNUM	(1u << 0)
 562#define	XFS_AGF_VERSIONNUM	(1u << 1)
 563#define	XFS_AGF_SEQNO		(1u << 2)
 564#define	XFS_AGF_LENGTH		(1u << 3)
 565#define	XFS_AGF_ROOTS		(1u << 4)
 566#define	XFS_AGF_LEVELS		(1u << 5)
 567#define	XFS_AGF_FLFIRST		(1u << 6)
 568#define	XFS_AGF_FLLAST		(1u << 7)
 569#define	XFS_AGF_FLCOUNT		(1u << 8)
 570#define	XFS_AGF_FREEBLKS	(1u << 9)
 571#define	XFS_AGF_LONGEST		(1u << 10)
 572#define	XFS_AGF_BTREEBLKS	(1u << 11)
 573#define	XFS_AGF_UUID		(1u << 12)
 574#define	XFS_AGF_RMAP_BLOCKS	(1u << 13)
 575#define	XFS_AGF_REFCOUNT_BLOCKS	(1u << 14)
 576#define	XFS_AGF_REFCOUNT_ROOT	(1u << 15)
 577#define	XFS_AGF_REFCOUNT_LEVEL	(1u << 16)
 578#define	XFS_AGF_SPARE64		(1u << 17)
 579#define	XFS_AGF_NUM_BITS	18
 580#define	XFS_AGF_ALL_BITS	((1u << XFS_AGF_NUM_BITS) - 1)
 581
 582#define XFS_AGF_FLAGS \
 583	{ XFS_AGF_MAGICNUM,	"MAGICNUM" }, \
 584	{ XFS_AGF_VERSIONNUM,	"VERSIONNUM" }, \
 585	{ XFS_AGF_SEQNO,	"SEQNO" }, \
 586	{ XFS_AGF_LENGTH,	"LENGTH" }, \
 587	{ XFS_AGF_ROOTS,	"ROOTS" }, \
 588	{ XFS_AGF_LEVELS,	"LEVELS" }, \
 589	{ XFS_AGF_FLFIRST,	"FLFIRST" }, \
 590	{ XFS_AGF_FLLAST,	"FLLAST" }, \
 591	{ XFS_AGF_FLCOUNT,	"FLCOUNT" }, \
 592	{ XFS_AGF_FREEBLKS,	"FREEBLKS" }, \
 593	{ XFS_AGF_LONGEST,	"LONGEST" }, \
 594	{ XFS_AGF_BTREEBLKS,	"BTREEBLKS" }, \
 595	{ XFS_AGF_UUID,		"UUID" }, \
 596	{ XFS_AGF_RMAP_BLOCKS,	"RMAP_BLOCKS" }, \
 597	{ XFS_AGF_REFCOUNT_BLOCKS,	"REFCOUNT_BLOCKS" }, \
 598	{ XFS_AGF_REFCOUNT_ROOT,	"REFCOUNT_ROOT" }, \
 599	{ XFS_AGF_REFCOUNT_LEVEL,	"REFCOUNT_LEVEL" }, \
 600	{ XFS_AGF_SPARE64,	"SPARE64" }
 601
 602/* disk block (xfs_daddr_t) in the AG */
 603#define XFS_AGF_DADDR(mp)	((xfs_daddr_t)(1 << (mp)->m_sectbb_log))
 604#define	XFS_AGF_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))
 605
 606/*
 607 * Size of the unlinked inode hash table in the agi.
 608 */
 609#define	XFS_AGI_UNLINKED_BUCKETS	64
 610
 611typedef struct xfs_agi {
 612	/*
 613	 * Common allocation group header information
 614	 */
 615	__be32		agi_magicnum;	/* magic number == XFS_AGI_MAGIC */
 616	__be32		agi_versionnum;	/* header version == XFS_AGI_VERSION */
 617	__be32		agi_seqno;	/* sequence # starting from 0 */
 618	__be32		agi_length;	/* size in blocks of a.g. */
 619	/*
 620	 * Inode information
 621	 * Inodes are mapped by interpreting the inode number, so no
 622	 * mapping data is needed here.
 623	 */
 624	__be32		agi_count;	/* count of allocated inodes */
 625	__be32		agi_root;	/* root of inode btree */
 626	__be32		agi_level;	/* levels in inode btree */
 627	__be32		agi_freecount;	/* number of free inodes */
 628
 629	__be32		agi_newino;	/* new inode just allocated */
 630	__be32		agi_dirino;	/* last directory inode chunk */
 631	/*
 632	 * Hash table of inodes which have been unlinked but are
 633	 * still being referenced.
 634	 */
 635	__be32		agi_unlinked[XFS_AGI_UNLINKED_BUCKETS];
 636	/*
 637	 * This marks the end of logging region 1 and start of logging region 2.
 638	 */
 639	uuid_t		agi_uuid;	/* uuid of filesystem */
 640	__be32		agi_crc;	/* crc of agi sector */
 641	__be32		agi_pad32;
 642	__be64		agi_lsn;	/* last write sequence */
 643
 644	__be32		agi_free_root; /* root of the free inode btree */
 645	__be32		agi_free_level;/* levels in free inode btree */
 646
 647	__be32		agi_iblocks;	/* inobt blocks used */
 648	__be32		agi_fblocks;	/* finobt blocks used */
 649
 650	/* structure must be padded to 64 bit alignment */
 651} xfs_agi_t;
 652
 653#define XFS_AGI_CRC_OFF		offsetof(struct xfs_agi, agi_crc)
 654
 655#define	XFS_AGI_MAGICNUM	(1u << 0)
 656#define	XFS_AGI_VERSIONNUM	(1u << 1)
 657#define	XFS_AGI_SEQNO		(1u << 2)
 658#define	XFS_AGI_LENGTH		(1u << 3)
 659#define	XFS_AGI_COUNT		(1u << 4)
 660#define	XFS_AGI_ROOT		(1u << 5)
 661#define	XFS_AGI_LEVEL		(1u << 6)
 662#define	XFS_AGI_FREECOUNT	(1u << 7)
 663#define	XFS_AGI_NEWINO		(1u << 8)
 664#define	XFS_AGI_DIRINO		(1u << 9)
 665#define	XFS_AGI_UNLINKED	(1u << 10)
 666#define	XFS_AGI_NUM_BITS_R1	11	/* end of the 1st agi logging region */
 667#define	XFS_AGI_ALL_BITS_R1	((1u << XFS_AGI_NUM_BITS_R1) - 1)
 668#define	XFS_AGI_FREE_ROOT	(1u << 11)
 669#define	XFS_AGI_FREE_LEVEL	(1u << 12)
 670#define	XFS_AGI_IBLOCKS		(1u << 13) /* both inobt/finobt block counters */
 671#define	XFS_AGI_NUM_BITS_R2	14
 672
 673/* disk block (xfs_daddr_t) in the AG */
 674#define XFS_AGI_DADDR(mp)	((xfs_daddr_t)(2 << (mp)->m_sectbb_log))
 675#define	XFS_AGI_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGI_DADDR(mp))
 676
 677/*
 678 * The third a.g. block contains the a.g. freelist, an array
 679 * of block pointers to blocks owned by the allocation btree code.
 680 */
 681#define XFS_AGFL_DADDR(mp)	((xfs_daddr_t)(3 << (mp)->m_sectbb_log))
 682#define	XFS_AGFL_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGFL_DADDR(mp))
 683#define	XFS_BUF_TO_AGFL(bp)	((struct xfs_agfl *)((bp)->b_addr))
 684
 685struct xfs_agfl {
 686	__be32		agfl_magicnum;
 687	__be32		agfl_seqno;
 688	uuid_t		agfl_uuid;
 689	__be64		agfl_lsn;
 690	__be32		agfl_crc;
 691} __attribute__((packed));
 692
 693#define XFS_AGFL_CRC_OFF	offsetof(struct xfs_agfl, agfl_crc)
 694
 695#define XFS_AGB_TO_FSB(mp,agno,agbno)	\
 696	(((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno))
 697#define	XFS_FSB_TO_AGNO(mp,fsbno)	\
 698	((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog))
 699#define	XFS_FSB_TO_AGBNO(mp,fsbno)	\
 700	((xfs_agblock_t)((fsbno) & xfs_mask32lo((mp)->m_sb.sb_agblklog)))
 701#define	XFS_AGB_TO_DADDR(mp,agno,agbno)	\
 702	((xfs_daddr_t)XFS_FSB_TO_BB(mp, \
 703		(xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno)))
 704#define	XFS_AG_DADDR(mp,agno,d)		(XFS_AGB_TO_DADDR(mp, agno, 0) + (d))
 705
 706/*
 707 * For checking for bad ranges of xfs_daddr_t's, covering multiple
 708 * allocation groups or a single xfs_daddr_t that's a superblock copy.
 709 */
 710#define	XFS_AG_CHECK_DADDR(mp,d,len)	\
 711	((len) == 1 ? \
 712	    ASSERT((d) == XFS_SB_DADDR || \
 713		   xfs_daddr_to_agbno(mp, d) != XFS_SB_DADDR) : \
 714	    ASSERT(xfs_daddr_to_agno(mp, d) == \
 715		   xfs_daddr_to_agno(mp, (d) + (len) - 1)))
 716
 717/*
 718 * Realtime bitmap information is accessed by the word, which is currently
 719 * stored in host-endian format.  Starting with the realtime groups feature,
 720 * the words are stored in be32 ondisk.
 721 */
 722union xfs_rtword_raw {
 723	__u32		old;
 724	__be32		rtg;
 725};
 726
 727/*
 728 * Realtime summary counts are accessed by the word, which is currently
 729 * stored in host-endian format.  Starting with the realtime groups feature,
 730 * the words are stored in be32 ondisk.
 731 */
 732union xfs_suminfo_raw {
 733	__u32		old;
 734	__be32		rtg;
 735};
 736
 737/*
 738 * Realtime allocation groups break the rt section into multiple pieces that
 739 * could be locked independently.  Realtime block group numbers are 32-bit
 740 * quantities.  Block numbers within a group are also 32-bit quantities, but
 741 * the upper bit must never be set.  rtgroup 0 might have a superblock in it,
 742 * so the minimum size of an rtgroup is 2 rtx.
 743 */
 744#define XFS_MAX_RGBLOCKS	((xfs_rgblock_t)(1U << 31) - 1)
 745#define XFS_MIN_RGEXTENTS	((xfs_rtxlen_t)2)
 746#define XFS_MAX_RGNUMBER	((xfs_rgnumber_t)(-1U))
 747
 748#define XFS_RTSB_MAGIC	0x46726F67	/* 'Frog' */
 749
 750/*
 751 * Realtime superblock - on disk version.  Must be padded to 64 bit alignment.
 752 * The first block of the realtime volume contains this superblock.
 753 */
 754struct xfs_rtsb {
 755	__be32		rsb_magicnum;	/* magic number == XFS_RTSB_MAGIC */
 756	__le32		rsb_crc;	/* superblock crc */
 757
 758	__be32		rsb_pad;	/* zero */
 759	unsigned char	rsb_fname[XFSLABEL_MAX]; /* file system name */
 760
 761	uuid_t		rsb_uuid;	/* user-visible file system unique id */
 762	uuid_t		rsb_meta_uuid;	/* metadata file system unique id */
 763
 764	/* must be padded to 64 bit alignment */
 765};
 766
 767#define XFS_RTSB_CRC_OFF	offsetof(struct xfs_rtsb, rsb_crc)
 768#define XFS_RTSB_DADDR		((xfs_daddr_t)0) /* daddr in rt section */
 769
 770/*
 771 * XFS Timestamps
 772 * ==============
 773 *
 774 * Traditional ondisk inode timestamps consist of signed 32-bit counters for
 775 * seconds and nanoseconds; time zero is the Unix epoch, Jan  1 00:00:00 UTC
 776 * 1970, which means that the timestamp epoch is the same as the Unix epoch.
 777 * Therefore, the ondisk min and max defined here can be used directly to
 778 * constrain the incore timestamps on a Unix system.  Note that we actually
 779 * encode a __be64 value on disk.
 780 *
 781 * When the bigtime feature is enabled, ondisk inode timestamps become an
 782 * unsigned 64-bit nanoseconds counter.  This means that the bigtime inode
 783 * timestamp epoch is the start of the classic timestamp range, which is
 784 * Dec 13 20:45:52 UTC 1901.  Because the epochs are not the same, callers
 785 * /must/ use the bigtime conversion functions when encoding and decoding raw
 786 * timestamps.
 787 */
 788typedef __be64 xfs_timestamp_t;
 789
 790/* Legacy timestamp encoding format. */
 791struct xfs_legacy_timestamp {
 792	__be32		t_sec;		/* timestamp seconds */
 793	__be32		t_nsec;		/* timestamp nanoseconds */
 794};
 795
 796/*
 797 * Smallest possible ondisk seconds value with traditional timestamps.  This
 798 * corresponds exactly with the incore timestamp Dec 13 20:45:52 UTC 1901.
 799 */
 800#define XFS_LEGACY_TIME_MIN	((int64_t)S32_MIN)
 801
 802/*
 803 * Largest possible ondisk seconds value with traditional timestamps.  This
 804 * corresponds exactly with the incore timestamp Jan 19 03:14:07 UTC 2038.
 805 */
 806#define XFS_LEGACY_TIME_MAX	((int64_t)S32_MAX)
 807
 808/*
 809 * Smallest possible ondisk seconds value with bigtime timestamps.  This
 810 * corresponds (after conversion to a Unix timestamp) with the traditional
 811 * minimum timestamp of Dec 13 20:45:52 UTC 1901.
 812 */
 813#define XFS_BIGTIME_TIME_MIN	((int64_t)0)
 814
 815/*
 816 * Largest supported ondisk seconds value with bigtime timestamps.  This
 817 * corresponds (after conversion to a Unix timestamp) with an incore timestamp
 818 * of Jul  2 20:20:24 UTC 2486.
 819 *
 820 * We round down the ondisk limit so that the bigtime quota and inode max
 821 * timestamps will be the same.
 822 */
 823#define XFS_BIGTIME_TIME_MAX	((int64_t)((-1ULL / NSEC_PER_SEC) & ~0x3ULL))
 824
 825/*
 826 * Bigtime epoch is set exactly to the minimum time value that a traditional
 827 * 32-bit timestamp can represent when using the Unix epoch as a reference.
 828 * Hence the Unix epoch is at a fixed offset into the supported bigtime
 829 * timestamp range.
 830 *
 831 * The bigtime epoch also matches the minimum value an on-disk 32-bit XFS
 832 * timestamp can represent so we will not lose any fidelity in converting
 833 * to/from unix and bigtime timestamps.
 834 *
 835 * The following conversion factor converts a seconds counter from the Unix
 836 * epoch to the bigtime epoch.
 837 */
 838#define XFS_BIGTIME_EPOCH_OFFSET	(-(int64_t)S32_MIN)
 839
 840/* Convert a timestamp from the Unix epoch to the bigtime epoch. */
 841static inline uint64_t xfs_unix_to_bigtime(time64_t unix_seconds)
 842{
 843	return (uint64_t)unix_seconds + XFS_BIGTIME_EPOCH_OFFSET;
 844}
 845
 846/* Convert a timestamp from the bigtime epoch to the Unix epoch. */
 847static inline time64_t xfs_bigtime_to_unix(uint64_t ondisk_seconds)
 848{
 849	return (time64_t)ondisk_seconds - XFS_BIGTIME_EPOCH_OFFSET;
 850}
 851
 852enum xfs_metafile_type {
 853	XFS_METAFILE_UNKNOWN,		/* unknown */
 854	XFS_METAFILE_DIR,		/* metadir directory */
 855	XFS_METAFILE_USRQUOTA,		/* user quota */
 856	XFS_METAFILE_GRPQUOTA,		/* group quota */
 857	XFS_METAFILE_PRJQUOTA,		/* project quota */
 858	XFS_METAFILE_RTBITMAP,		/* rt bitmap */
 859	XFS_METAFILE_RTSUMMARY,		/* rt summary */
 860
 861	XFS_METAFILE_MAX
 862} __packed;
 863
 864#define XFS_METAFILE_TYPE_STR \
 865	{ XFS_METAFILE_UNKNOWN,		"unknown" }, \
 866	{ XFS_METAFILE_DIR,		"dir" }, \
 867	{ XFS_METAFILE_USRQUOTA,	"usrquota" }, \
 868	{ XFS_METAFILE_GRPQUOTA,	"grpquota" }, \
 869	{ XFS_METAFILE_PRJQUOTA,	"prjquota" }, \
 870	{ XFS_METAFILE_RTBITMAP,	"rtbitmap" }, \
 871	{ XFS_METAFILE_RTSUMMARY,	"rtsummary" }
 872
 873/*
 874 * On-disk inode structure.
 875 *
 876 * This is just the header or "dinode core", the inode is expanded to fill a
 877 * variable size the leftover area split into a data and an attribute fork.
 878 * The format of the data and attribute fork depends on the format of the
 879 * inode as indicated by di_format and di_aformat.  To access the data and
 880 * attribute use the XFS_DFORK_DPTR, XFS_DFORK_APTR, and XFS_DFORK_PTR macros
 881 * below.
 882 *
 883 * There is a very similar struct xfs_log_dinode which matches the layout of
 884 * this structure, but is kept in native format instead of big endian.
 885 *
 886 * Note: di_flushiter is only used by v1/2 inodes - it's effectively a zeroed
 887 * padding field for v3 inodes.
 888 */
 889#define	XFS_DINODE_MAGIC		0x494e	/* 'IN' */
 890struct xfs_dinode {
 891	__be16		di_magic;	/* inode magic # = XFS_DINODE_MAGIC */
 892	__be16		di_mode;	/* mode and type of file */
 893	__u8		di_version;	/* inode version */
 894	__u8		di_format;	/* format of di_c data */
 895	__be16		di_metatype;	/* XFS_METAFILE_*; was di_onlink */
 896	__be32		di_uid;		/* owner's user id */
 897	__be32		di_gid;		/* owner's group id */
 898	__be32		di_nlink;	/* number of links to file */
 899	__be16		di_projid_lo;	/* lower part of owner's project id */
 900	__be16		di_projid_hi;	/* higher part owner's project id */
 901	union {
 902		/* Number of data fork extents if NREXT64 is set */
 903		__be64	di_big_nextents;
 904
 905		/* Padding for V3 inodes without NREXT64 set. */
 906		__be64	di_v3_pad;
 907
 908		/* Padding and inode flush counter for V2 inodes. */
 909		struct {
 910			__u8	di_v2_pad[6];
 911			__be16	di_flushiter;
 912		};
 913	};
 914	xfs_timestamp_t	di_atime;	/* time last accessed */
 915	xfs_timestamp_t	di_mtime;	/* time last modified */
 916	xfs_timestamp_t	di_ctime;	/* time created/inode modified */
 917	__be64		di_size;	/* number of bytes in file */
 918	__be64		di_nblocks;	/* # of direct & btree blocks used */
 919	__be32		di_extsize;	/* basic/minimum extent size for file */
 920	union {
 921		/*
 922		 * For V2 inodes and V3 inodes without NREXT64 set, this
 923		 * is the number of data and attr fork extents.
 924		 */
 925		struct {
 926			__be32	di_nextents;
 927			__be16	di_anextents;
 928		} __packed;
 929
 930		/* Number of attr fork extents if NREXT64 is set. */
 931		struct {
 932			__be32	di_big_anextents;
 933			__be16	di_nrext64_pad;
 934		} __packed;
 935	} __packed;
 936	__u8		di_forkoff;	/* attr fork offs, <<3 for 64b align */
 937	__s8		di_aformat;	/* format of attr fork's data */
 938	__be32		di_dmevmask;	/* DMIG event mask */
 939	__be16		di_dmstate;	/* DMIG state info */
 940	__be16		di_flags;	/* random flags, XFS_DIFLAG_... */
 941	__be32		di_gen;		/* generation number */
 942
 943	/* di_next_unlinked is the only non-core field in the old dinode */
 944	__be32		di_next_unlinked;/* agi unlinked list ptr */
 945
 946	/* start of the extended dinode, writable fields */
 947	__le32		di_crc;		/* CRC of the inode */
 948	__be64		di_changecount;	/* number of attribute changes */
 949	__be64		di_lsn;		/* flush sequence */
 950	__be64		di_flags2;	/* more random flags */
 951	__be32		di_cowextsize;	/* basic cow extent size for file */
 952	__u8		di_pad2[12];	/* more padding for future expansion */
 953
 954	/* fields only written to during inode creation */
 955	xfs_timestamp_t	di_crtime;	/* time created */
 956	__be64		di_ino;		/* inode number */
 957	uuid_t		di_uuid;	/* UUID of the filesystem */
 958
 959	/* structure must be padded to 64 bit alignment */
 960};
 961
 962#define XFS_DINODE_CRC_OFF	offsetof(struct xfs_dinode, di_crc)
 963
 964#define DI_MAX_FLUSH 0xffff
 965
 966/*
 967 * Size of the core inode on disk.  Version 1 and 2 inodes have
 968 * the same size, but version 3 has grown a few additional fields.
 969 */
 970static inline uint xfs_dinode_size(int version)
 971{
 972	if (version == 3)
 973		return sizeof(struct xfs_dinode);
 974	return offsetof(struct xfs_dinode, di_crc);
 975}
 976
 977/*
 978 * The 32 bit link count in the inode theoretically maxes out at UINT_MAX.
 979 * Since the pathconf interface is signed, we use 2^31 - 1 instead.
 980 */
 981#define	XFS_MAXLINK		((1U << 31) - 1U)
 982
 983/*
 984 * Any file that hits the maximum ondisk link count should be pinned to avoid
 985 * a use-after-free situation.
 986 */
 987#define	XFS_NLINK_PINNED	(~0U)
 988
 989/*
 990 * Values for di_format
 991 *
 992 * This enum is used in string mapping in xfs_trace.h; please keep the
 993 * TRACE_DEFINE_ENUMs for it up to date.
 994 */
 995enum xfs_dinode_fmt {
 996	XFS_DINODE_FMT_DEV,		/* xfs_dev_t */
 997	XFS_DINODE_FMT_LOCAL,		/* bulk data */
 998	XFS_DINODE_FMT_EXTENTS,		/* struct xfs_bmbt_rec */
 999	XFS_DINODE_FMT_BTREE,		/* struct xfs_bmdr_block */
1000	XFS_DINODE_FMT_UUID		/* added long ago, but never used */
1001};
1002
1003#define XFS_INODE_FORMAT_STR \
1004	{ XFS_DINODE_FMT_DEV,		"dev" }, \
1005	{ XFS_DINODE_FMT_LOCAL,		"local" }, \
1006	{ XFS_DINODE_FMT_EXTENTS,	"extent" }, \
1007	{ XFS_DINODE_FMT_BTREE,		"btree" }, \
1008	{ XFS_DINODE_FMT_UUID,		"uuid" }
1009
1010/*
1011 * Max values for extnum and aextnum.
1012 *
1013 * The original on-disk extent counts were held in signed fields, resulting in
1014 * maximum extent counts of 2^31 and 2^15 for the data and attr forks
1015 * respectively. Similarly the maximum extent length is limited to 2^21 blocks
1016 * by the 21-bit wide blockcount field of a BMBT extent record.
1017 *
1018 * The newly introduced data fork extent counter can hold a 64-bit value,
1019 * however the maximum number of extents in a file is also limited to 2^54
1020 * extents by the 54-bit wide startoff field of a BMBT extent record.
1021 *
1022 * It is further limited by the maximum supported file size of 2^63
1023 * *bytes*. This leads to a maximum extent count for maximally sized filesystem
1024 * blocks (64kB) of:
1025 *
1026 * 2^63 bytes / 2^16 bytes per block = 2^47 blocks
1027 *
1028 * Rounding up 47 to the nearest multiple of bits-per-byte results in 48. Hence
1029 * 2^48 was chosen as the maximum data fork extent count.
1030 *
1031 * The maximum file size that can be represented by the data fork extent counter
1032 * in the worst case occurs when all extents are 1 block in length and each
1033 * block is 1KB in size.
1034 *
1035 * With XFS_MAX_EXTCNT_DATA_FORK_SMALL representing maximum extent count and
1036 * with 1KB sized blocks, a file can reach upto,
1037 * 1KB * (2^31) = 2TB
1038 *
1039 * This is much larger than the theoretical maximum size of a directory
1040 * i.e. XFS_DIR2_SPACE_SIZE * XFS_DIR2_MAX_SPACES = ~96GB.
1041 *
1042 * Hence, a directory inode can never overflow its data fork extent counter.
1043 */
1044#define XFS_MAX_EXTCNT_DATA_FORK_LARGE	((xfs_extnum_t)((1ULL << 48) - 1))
1045#define XFS_MAX_EXTCNT_ATTR_FORK_LARGE	((xfs_extnum_t)((1ULL << 32) - 1))
1046#define XFS_MAX_EXTCNT_DATA_FORK_SMALL	((xfs_extnum_t)((1ULL << 31) - 1))
1047#define XFS_MAX_EXTCNT_ATTR_FORK_SMALL	((xfs_extnum_t)((1ULL << 15) - 1))
1048
1049/*
1050 * When we upgrade an inode to the large extent counts, the maximum value by
1051 * which the extent count can increase is bound by the change in size of the
1052 * on-disk field. No upgrade operation should ever be adding more than a few
1053 * tens of extents, so if we get a really large value it is a sign of a code bug
1054 * or corruption.
1055 */
1056#define XFS_MAX_EXTCNT_UPGRADE_NR	\
1057	min(XFS_MAX_EXTCNT_ATTR_FORK_LARGE - XFS_MAX_EXTCNT_ATTR_FORK_SMALL,	\
1058	    XFS_MAX_EXTCNT_DATA_FORK_LARGE - XFS_MAX_EXTCNT_DATA_FORK_SMALL)
1059
1060/*
1061 * Inode minimum and maximum sizes.
1062 */
1063#define	XFS_DINODE_MIN_LOG	8
1064#define	XFS_DINODE_MAX_LOG	11
1065#define	XFS_DINODE_MIN_SIZE	(1 << XFS_DINODE_MIN_LOG)
1066#define	XFS_DINODE_MAX_SIZE	(1 << XFS_DINODE_MAX_LOG)
1067
1068/*
1069 * Inode size for given fs.
1070 */
1071#define XFS_DINODE_SIZE(mp) \
1072	(xfs_has_v3inodes(mp) ? \
1073		sizeof(struct xfs_dinode) : \
1074		offsetof(struct xfs_dinode, di_crc))
1075#define XFS_LITINO(mp) \
1076	((mp)->m_sb.sb_inodesize - XFS_DINODE_SIZE(mp))
1077
1078/*
1079 * Inode data & attribute fork sizes, per inode.
1080 */
1081#define XFS_DFORK_BOFF(dip)		((int)((dip)->di_forkoff << 3))
1082
1083#define XFS_DFORK_DSIZE(dip,mp) \
1084	((dip)->di_forkoff ? XFS_DFORK_BOFF(dip) : XFS_LITINO(mp))
1085#define XFS_DFORK_ASIZE(dip,mp) \
1086	((dip)->di_forkoff ? XFS_LITINO(mp) - XFS_DFORK_BOFF(dip) : 0)
1087#define XFS_DFORK_SIZE(dip,mp,w) \
1088	((w) == XFS_DATA_FORK ? \
1089		XFS_DFORK_DSIZE(dip, mp) : \
1090		XFS_DFORK_ASIZE(dip, mp))
1091
1092#define XFS_DFORK_MAXEXT(dip, mp, w) \
1093	(XFS_DFORK_SIZE(dip, mp, w) / sizeof(struct xfs_bmbt_rec))
1094
1095/*
1096 * Return pointers to the data or attribute forks.
1097 */
1098#define XFS_DFORK_DPTR(dip) \
1099	((void *)dip + xfs_dinode_size(dip->di_version))
1100#define XFS_DFORK_APTR(dip)	\
1101	(XFS_DFORK_DPTR(dip) + XFS_DFORK_BOFF(dip))
1102#define XFS_DFORK_PTR(dip,w)	\
1103	((w) == XFS_DATA_FORK ? XFS_DFORK_DPTR(dip) : XFS_DFORK_APTR(dip))
1104
1105#define XFS_DFORK_FORMAT(dip,w) \
1106	((w) == XFS_DATA_FORK ? \
1107		(dip)->di_format : \
1108		(dip)->di_aformat)
1109
1110/*
1111 * For block and character special files the 32bit dev_t is stored at the
1112 * beginning of the data fork.
1113 */
1114static inline xfs_dev_t xfs_dinode_get_rdev(struct xfs_dinode *dip)
1115{
1116	return be32_to_cpu(*(__be32 *)XFS_DFORK_DPTR(dip));
1117}
1118
1119static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
1120{
1121	*(__be32 *)XFS_DFORK_DPTR(dip) = cpu_to_be32(rdev);
1122}
1123
1124/*
1125 * Values for di_flags
1126 */
1127#define XFS_DIFLAG_REALTIME_BIT  0	/* file's blocks come from rt area */
1128#define XFS_DIFLAG_PREALLOC_BIT  1	/* file space has been preallocated */
1129#define XFS_DIFLAG_NEWRTBM_BIT   2	/* for rtbitmap inode, new format */
1130#define XFS_DIFLAG_IMMUTABLE_BIT 3	/* inode is immutable */
1131#define XFS_DIFLAG_APPEND_BIT    4	/* inode is append-only */
1132#define XFS_DIFLAG_SYNC_BIT      5	/* inode is written synchronously */
1133#define XFS_DIFLAG_NOATIME_BIT   6	/* do not update atime */
1134#define XFS_DIFLAG_NODUMP_BIT    7	/* do not dump */
1135#define XFS_DIFLAG_RTINHERIT_BIT 8	/* create with realtime bit set */
1136#define XFS_DIFLAG_PROJINHERIT_BIT   9	/* create with parents projid */
1137#define XFS_DIFLAG_NOSYMLINKS_BIT   10	/* disallow symlink creation */
1138#define XFS_DIFLAG_EXTSIZE_BIT      11	/* inode extent size allocator hint */
1139#define XFS_DIFLAG_EXTSZINHERIT_BIT 12	/* inherit inode extent size */
1140#define XFS_DIFLAG_NODEFRAG_BIT     13	/* do not reorganize/defragment */
1141#define XFS_DIFLAG_FILESTREAM_BIT   14  /* use filestream allocator */
1142/* Do not use bit 15, di_flags is legacy and unchanging now */
1143
1144#define XFS_DIFLAG_REALTIME      (1 << XFS_DIFLAG_REALTIME_BIT)
1145#define XFS_DIFLAG_PREALLOC      (1 << XFS_DIFLAG_PREALLOC_BIT)
1146#define XFS_DIFLAG_NEWRTBM       (1 << XFS_DIFLAG_NEWRTBM_BIT)
1147#define XFS_DIFLAG_IMMUTABLE     (1 << XFS_DIFLAG_IMMUTABLE_BIT)
1148#define XFS_DIFLAG_APPEND        (1 << XFS_DIFLAG_APPEND_BIT)
1149#define XFS_DIFLAG_SYNC          (1 << XFS_DIFLAG_SYNC_BIT)
1150#define XFS_DIFLAG_NOATIME       (1 << XFS_DIFLAG_NOATIME_BIT)
1151#define XFS_DIFLAG_NODUMP        (1 << XFS_DIFLAG_NODUMP_BIT)
1152#define XFS_DIFLAG_RTINHERIT     (1 << XFS_DIFLAG_RTINHERIT_BIT)
1153#define XFS_DIFLAG_PROJINHERIT   (1 << XFS_DIFLAG_PROJINHERIT_BIT)
1154#define XFS_DIFLAG_NOSYMLINKS    (1 << XFS_DIFLAG_NOSYMLINKS_BIT)
1155#define XFS_DIFLAG_EXTSIZE       (1 << XFS_DIFLAG_EXTSIZE_BIT)
1156#define XFS_DIFLAG_EXTSZINHERIT  (1 << XFS_DIFLAG_EXTSZINHERIT_BIT)
1157#define XFS_DIFLAG_NODEFRAG      (1 << XFS_DIFLAG_NODEFRAG_BIT)
1158#define XFS_DIFLAG_FILESTREAM    (1 << XFS_DIFLAG_FILESTREAM_BIT)
1159
1160#define XFS_DIFLAG_ANY \
1161	(XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \
1162	 XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \
1163	 XFS_DIFLAG_NOATIME | XFS_DIFLAG_NODUMP | XFS_DIFLAG_RTINHERIT | \
1164	 XFS_DIFLAG_PROJINHERIT | XFS_DIFLAG_NOSYMLINKS | XFS_DIFLAG_EXTSIZE | \
1165	 XFS_DIFLAG_EXTSZINHERIT | XFS_DIFLAG_NODEFRAG | XFS_DIFLAG_FILESTREAM)
1166
1167/*
1168 * Values for di_flags2 These start by being exposed to userspace in the upper
1169 * 16 bits of the XFS_XFLAG_s range.
1170 */
1171/* use DAX for this inode */
1172#define XFS_DIFLAG2_DAX_BIT		0
1173
1174/* file's blocks may be shared */
1175#define XFS_DIFLAG2_REFLINK_BIT		1
1176
1177/* copy on write extent size hint */
1178#define XFS_DIFLAG2_COWEXTSIZE_BIT	2
1179
1180/* big timestamps */
1181#define XFS_DIFLAG2_BIGTIME_BIT		3
1182
1183/* large extent counters */
1184#define XFS_DIFLAG2_NREXT64_BIT		4
1185
1186/*
1187 * The inode contains filesystem metadata and can be found through the metadata
1188 * directory tree.  Metadata inodes must satisfy the following constraints:
1189 *
1190 * - V5 filesystem (and ftype) are enabled;
1191 * - The only valid modes are regular files and directories;
1192 * - The access bits must be zero;
1193 * - DMAPI event and state masks are zero;
1194 * - The user and group IDs must be zero;
1195 * - The project ID can be used as a u32 annotation;
1196 * - The immutable, sync, noatime, nodump, nodefrag flags must be set.
1197 * - The dax flag must not be set.
1198 * - Directories must have nosymlinks set.
1199 *
1200 * These requirements are chosen defensively to minimize the ability of
1201 * userspace to read or modify the contents, should a metadata file ever
1202 * escape to userspace.
1203 *
1204 * There are further constraints on the directory tree itself:
1205 *
1206 * - Metadata inodes must never be resolvable through the root directory;
1207 * - They must never be accessed by userspace;
1208 * - Metadata directory entries must have correct ftype.
1209 *
1210 * Superblock-rooted metadata files must have the METADATA iflag set even
1211 * though they do not have a parent directory.
1212 */
1213#define XFS_DIFLAG2_METADATA_BIT	5
1214
1215#define XFS_DIFLAG2_DAX		(1ULL << XFS_DIFLAG2_DAX_BIT)
1216#define XFS_DIFLAG2_REFLINK	(1ULL << XFS_DIFLAG2_REFLINK_BIT)
1217#define XFS_DIFLAG2_COWEXTSIZE	(1ULL << XFS_DIFLAG2_COWEXTSIZE_BIT)
1218#define XFS_DIFLAG2_BIGTIME	(1ULL << XFS_DIFLAG2_BIGTIME_BIT)
1219#define XFS_DIFLAG2_NREXT64	(1ULL << XFS_DIFLAG2_NREXT64_BIT)
1220#define XFS_DIFLAG2_METADATA	(1ULL << XFS_DIFLAG2_METADATA_BIT)
1221
1222#define XFS_DIFLAG2_ANY \
1223	(XFS_DIFLAG2_DAX | XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE | \
1224	 XFS_DIFLAG2_BIGTIME | XFS_DIFLAG2_NREXT64 | XFS_DIFLAG2_METADATA)
1225
1226static inline bool xfs_dinode_has_bigtime(const struct xfs_dinode *dip)
1227{
1228	return dip->di_version >= 3 &&
1229	       (dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_BIGTIME));
1230}
1231
1232static inline bool xfs_dinode_has_large_extent_counts(
1233	const struct xfs_dinode *dip)
1234{
1235	return dip->di_version >= 3 &&
1236	       (dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_NREXT64));
1237}
1238
1239static inline bool xfs_dinode_is_metadir(const struct xfs_dinode *dip)
1240{
1241	return dip->di_version >= 3 &&
1242	       (dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_METADATA));
1243}
1244
1245/*
1246 * Inode number format:
1247 * low inopblog bits - offset in block
1248 * next agblklog bits - block number in ag
1249 * next agno_log bits - ag number
1250 * high agno_log-agblklog-inopblog bits - 0
1251 */
1252#define	XFS_INO_MASK(k)			(uint32_t)((1ULL << (k)) - 1)
1253#define	XFS_INO_OFFSET_BITS(mp)		(mp)->m_sb.sb_inopblog
1254#define	XFS_INO_AGBNO_BITS(mp)		(mp)->m_sb.sb_agblklog
1255#define	XFS_INO_AGINO_BITS(mp)		((mp)->m_ino_geo.agino_log)
1256#define	XFS_INO_AGNO_BITS(mp)		(mp)->m_agno_log
1257#define	XFS_INO_BITS(mp)		\
1258	XFS_INO_AGNO_BITS(mp) + XFS_INO_AGINO_BITS(mp)
1259#define	XFS_INO_TO_AGNO(mp,i)		\
1260	((xfs_agnumber_t)((i) >> XFS_INO_AGINO_BITS(mp)))
1261#define	XFS_INO_TO_AGINO(mp,i)		\
1262	((xfs_agino_t)(i) & XFS_INO_MASK(XFS_INO_AGINO_BITS(mp)))
1263#define	XFS_INO_TO_AGBNO(mp,i)		\
1264	(((xfs_agblock_t)(i) >> XFS_INO_OFFSET_BITS(mp)) & \
1265		XFS_INO_MASK(XFS_INO_AGBNO_BITS(mp)))
1266#define	XFS_INO_TO_OFFSET(mp,i)		\
1267	((int)(i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1268#define	XFS_INO_TO_FSB(mp,i)		\
1269	XFS_AGB_TO_FSB(mp, XFS_INO_TO_AGNO(mp,i), XFS_INO_TO_AGBNO(mp,i))
1270#define	XFS_AGINO_TO_INO(mp,a,i)	\
1271	(((xfs_ino_t)(a) << XFS_INO_AGINO_BITS(mp)) | (i))
1272#define	XFS_AGINO_TO_AGBNO(mp,i)	((i) >> XFS_INO_OFFSET_BITS(mp))
1273#define	XFS_AGINO_TO_OFFSET(mp,i)	\
1274	((i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1275#define	XFS_OFFBNO_TO_AGINO(mp,b,o)	\
1276	((xfs_agino_t)(((b) << XFS_INO_OFFSET_BITS(mp)) | (o)))
1277#define	XFS_FSB_TO_INO(mp, b)	((xfs_ino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
1278#define	XFS_AGB_TO_AGINO(mp, b)	((xfs_agino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
1279
1280#define	XFS_MAXINUMBER		((xfs_ino_t)((1ULL << 56) - 1ULL))
1281#define	XFS_MAXINUMBER_32	((xfs_ino_t)((1ULL << 32) - 1ULL))
1282
1283/*
1284 * RealTime Device format definitions
1285 */
1286
1287/* Min and max rt extent sizes, specified in bytes */
1288#define	XFS_MAX_RTEXTSIZE	(1024 * 1024 * 1024)	/* 1GB */
1289#define	XFS_DFL_RTEXTSIZE	(64 * 1024)	        /* 64kB */
1290#define	XFS_MIN_RTEXTSIZE	(4 * 1024)		/* 4kB */
1291
 
 
 
 
 
1292/*
1293 * RT bit manipulation macros.
1294 */
1295#define XFS_RTBITMAP_MAGIC	0x424D505A	/* BMPZ */
1296#define XFS_RTSUMMARY_MAGIC	0x53554D59	/* SUMY */
 
 
 
 
1297
1298struct xfs_rtbuf_blkinfo {
1299	__be32		rt_magic;	/* validity check on block */
1300	__be32		rt_crc;		/* CRC of block */
1301	__be64		rt_owner;	/* inode that owns the block */
1302	__be64		rt_blkno;	/* first block of the buffer */
1303	__be64		rt_lsn;		/* sequence number of last write */
1304	uuid_t		rt_uuid;	/* filesystem we belong to */
1305};
 
 
1306
1307#define XFS_RTBUF_CRC_OFF \
1308	offsetof(struct xfs_rtbuf_blkinfo, rt_crc)
1309
1310/*
1311 * Dquot and dquot block format definitions
1312 */
1313#define XFS_DQUOT_MAGIC		0x4451		/* 'DQ' */
1314#define XFS_DQUOT_VERSION	(uint8_t)0x01	/* latest version number */
1315
1316#define XFS_DQTYPE_USER		(1u << 0)	/* user dquot record */
1317#define XFS_DQTYPE_PROJ		(1u << 1)	/* project dquot record */
1318#define XFS_DQTYPE_GROUP	(1u << 2)	/* group dquot record */
1319#define XFS_DQTYPE_BIGTIME	(1u << 7)	/* large expiry timestamps */
1320
1321/* bitmask to determine if this is a user/group/project dquot */
1322#define XFS_DQTYPE_REC_MASK	(XFS_DQTYPE_USER | \
1323				 XFS_DQTYPE_PROJ | \
1324				 XFS_DQTYPE_GROUP)
1325
1326#define XFS_DQTYPE_ANY		(XFS_DQTYPE_REC_MASK | \
1327				 XFS_DQTYPE_BIGTIME)
1328
1329/*
1330 * XFS Quota Timers
1331 * ================
1332 *
1333 * Traditional quota grace period expiration timers are an unsigned 32-bit
1334 * seconds counter; time zero is the Unix epoch, Jan  1 00:00:01 UTC 1970.
1335 * Note that an expiration value of zero means that the quota limit has not
1336 * been reached, and therefore no expiration has been set.  Therefore, the
1337 * ondisk min and max defined here can be used directly to constrain the incore
1338 * quota expiration timestamps on a Unix system.
1339 *
1340 * When bigtime is enabled, we trade two bits of precision to expand the
1341 * expiration timeout range to match that of big inode timestamps.  The min and
1342 * max recorded here are the on-disk limits, not a Unix timestamp.
1343 *
1344 * The grace period for each quota type is stored in the root dquot (id = 0)
1345 * and is applied to a non-root dquot when it exceeds the soft or hard limits.
1346 * The length of quota grace periods are unsigned 32-bit quantities measured in
1347 * units of seconds.  A value of zero means to use the default period.
1348 */
1349
1350/*
1351 * Smallest possible ondisk quota expiration value with traditional timestamps.
1352 * This corresponds exactly with the incore expiration Jan  1 00:00:01 UTC 1970.
1353 */
1354#define XFS_DQ_LEGACY_EXPIRY_MIN	((int64_t)1)
1355
1356/*
1357 * Largest possible ondisk quota expiration value with traditional timestamps.
1358 * This corresponds exactly with the incore expiration Feb  7 06:28:15 UTC 2106.
1359 */
1360#define XFS_DQ_LEGACY_EXPIRY_MAX	((int64_t)U32_MAX)
1361
1362/*
1363 * Smallest possible ondisk quota expiration value with bigtime timestamps.
1364 * This corresponds (after conversion to a Unix timestamp) with the incore
1365 * expiration of Jan  1 00:00:04 UTC 1970.
1366 */
1367#define XFS_DQ_BIGTIME_EXPIRY_MIN	(XFS_DQ_LEGACY_EXPIRY_MIN)
1368
1369/*
1370 * Largest supported ondisk quota expiration value with bigtime timestamps.
1371 * This corresponds (after conversion to a Unix timestamp) with an incore
1372 * expiration of Jul  2 20:20:24 UTC 2486.
1373 *
1374 * The ondisk field supports values up to -1U, which corresponds to an incore
1375 * expiration in 2514.  This is beyond the maximum the bigtime inode timestamp,
1376 * so we cap the maximum bigtime quota expiration to the max inode timestamp.
1377 */
1378#define XFS_DQ_BIGTIME_EXPIRY_MAX	((int64_t)4074815106U)
1379
1380/*
1381 * The following conversion factors assist in converting a quota expiration
1382 * timestamp between the incore and ondisk formats.
1383 */
1384#define XFS_DQ_BIGTIME_SHIFT	(2)
1385#define XFS_DQ_BIGTIME_SLACK	((int64_t)(1ULL << XFS_DQ_BIGTIME_SHIFT) - 1)
1386
1387/* Convert an incore quota expiration timestamp to an ondisk bigtime value. */
1388static inline uint32_t xfs_dq_unix_to_bigtime(time64_t unix_seconds)
1389{
1390	/*
1391	 * Round the expiration timestamp up to the nearest bigtime timestamp
1392	 * that we can store, to give users the most time to fix problems.
1393	 */
1394	return ((uint64_t)unix_seconds + XFS_DQ_BIGTIME_SLACK) >>
1395			XFS_DQ_BIGTIME_SHIFT;
1396}
1397
1398/* Convert an ondisk bigtime quota expiration value to an incore timestamp. */
1399static inline time64_t xfs_dq_bigtime_to_unix(uint32_t ondisk_seconds)
1400{
1401	return (time64_t)ondisk_seconds << XFS_DQ_BIGTIME_SHIFT;
1402}
1403
1404/*
1405 * Default quota grace periods, ranging from zero (use the compiled defaults)
1406 * to ~136 years.  These are applied to a non-root dquot that has exceeded
1407 * either limit.
1408 */
1409#define XFS_DQ_GRACE_MIN		((int64_t)0)
1410#define XFS_DQ_GRACE_MAX		((int64_t)U32_MAX)
1411
1412/* Maximum id value for a quota record */
1413#define XFS_DQ_ID_MAX			(U32_MAX)
1414
1415/*
1416 * This is the main portion of the on-disk representation of quota information
1417 * for a user.  We pad this with some more expansion room to construct the on
1418 * disk structure.
1419 */
1420struct xfs_disk_dquot {
1421	__be16		d_magic;	/* dquot magic = XFS_DQUOT_MAGIC */
1422	__u8		d_version;	/* dquot version */
1423	__u8		d_type;		/* XFS_DQTYPE_USER/PROJ/GROUP */
1424	__be32		d_id;		/* user,project,group id */
1425	__be64		d_blk_hardlimit;/* absolute limit on disk blks */
1426	__be64		d_blk_softlimit;/* preferred limit on disk blks */
1427	__be64		d_ino_hardlimit;/* maximum # allocated inodes */
1428	__be64		d_ino_softlimit;/* preferred inode limit */
1429	__be64		d_bcount;	/* disk blocks owned by the user */
1430	__be64		d_icount;	/* inodes owned by the user */
1431	__be32		d_itimer;	/* zero if within inode limits if not,
1432					   this is when we refuse service */
1433	__be32		d_btimer;	/* similar to above; for disk blocks */
1434	__be16		d_iwarns;	/* warnings issued wrt num inodes */
1435	__be16		d_bwarns;	/* warnings issued wrt disk blocks */
1436	__be32		d_pad0;		/* 64 bit align */
1437	__be64		d_rtb_hardlimit;/* absolute limit on realtime blks */
1438	__be64		d_rtb_softlimit;/* preferred limit on RT disk blks */
1439	__be64		d_rtbcount;	/* realtime blocks owned */
1440	__be32		d_rtbtimer;	/* similar to above; for RT disk blocks */
1441	__be16		d_rtbwarns;	/* warnings issued wrt RT disk blocks */
1442	__be16		d_pad;
1443};
1444
1445/*
1446 * This is what goes on disk. This is separated from the xfs_disk_dquot because
1447 * carrying the unnecessary padding would be a waste of memory.
1448 */
1449struct xfs_dqblk {
1450	struct xfs_disk_dquot	dd_diskdq; /* portion living incore as well */
1451	char			dd_fill[4];/* filling for posterity */
1452
1453	/*
1454	 * These two are only present on filesystems with the CRC bits set.
1455	 */
1456	__be32		  dd_crc;	/* checksum */
1457	__be64		  dd_lsn;	/* last modification in log */
1458	uuid_t		  dd_uuid;	/* location information */
1459};
1460
1461#define XFS_DQUOT_CRC_OFF	offsetof(struct xfs_dqblk, dd_crc)
1462
1463/*
1464 * This defines the unit of allocation of dquots.
1465 *
1466 * Currently, it is just one file system block, and a 4K blk contains 30
1467 * (136 * 30 = 4080) dquots. It's probably not worth trying to make
1468 * this more dynamic.
1469 *
1470 * However, if this number is changed, we have to make sure that we don't
1471 * implicitly assume that we do allocations in chunks of a single filesystem
1472 * block in the dquot/xqm code.
1473 *
1474 * This is part of the ondisk format because the structure size is not a power
1475 * of two, which leaves slack at the end of the disk block.
1476 */
1477#define XFS_DQUOT_CLUSTER_SIZE_FSB	(xfs_filblks_t)1
1478
1479/*
1480 * Remote symlink format and access functions.
1481 */
1482#define XFS_SYMLINK_MAGIC	0x58534c4d	/* XSLM */
1483
1484struct xfs_dsymlink_hdr {
1485	__be32	sl_magic;
1486	__be32	sl_offset;
1487	__be32	sl_bytes;
1488	__be32	sl_crc;
1489	uuid_t	sl_uuid;
1490	__be64	sl_owner;
1491	__be64	sl_blkno;
1492	__be64	sl_lsn;
1493};
1494
1495#define XFS_SYMLINK_CRC_OFF	offsetof(struct xfs_dsymlink_hdr, sl_crc)
1496
1497#define XFS_SYMLINK_MAXLEN	1024
1498/*
1499 * The maximum pathlen is 1024 bytes. Since the minimum file system
1500 * blocksize is 512 bytes, we can get a max of 3 extents back from
1501 * bmapi when crc headers are taken into account.
1502 */
1503#define XFS_SYMLINK_MAPS 3
1504
1505#define XFS_SYMLINK_BUF_SPACE(mp, bufsize)	\
1506	((bufsize) - (xfs_has_crc((mp)) ? \
1507			sizeof(struct xfs_dsymlink_hdr) : 0))
1508
1509
1510/*
1511 * Allocation Btree format definitions
1512 *
1513 * There are two on-disk btrees, one sorted by blockno and one sorted
1514 * by blockcount and blockno.  All blocks look the same to make the code
1515 * simpler; if we have time later, we'll make the optimizations.
1516 */
1517#define	XFS_ABTB_MAGIC		0x41425442	/* 'ABTB' for bno tree */
1518#define	XFS_ABTB_CRC_MAGIC	0x41423342	/* 'AB3B' */
1519#define	XFS_ABTC_MAGIC		0x41425443	/* 'ABTC' for cnt tree */
1520#define	XFS_ABTC_CRC_MAGIC	0x41423343	/* 'AB3C' */
1521
1522/*
1523 * Data record/key structure
1524 */
1525typedef struct xfs_alloc_rec {
1526	__be32		ar_startblock;	/* starting block number */
1527	__be32		ar_blockcount;	/* count of free blocks */
1528} xfs_alloc_rec_t, xfs_alloc_key_t;
1529
1530typedef struct xfs_alloc_rec_incore {
1531	xfs_agblock_t	ar_startblock;	/* starting block number */
1532	xfs_extlen_t	ar_blockcount;	/* count of free blocks */
1533} xfs_alloc_rec_incore_t;
1534
1535/* btree pointer type */
1536typedef __be32 xfs_alloc_ptr_t;
1537
1538/*
1539 * Block numbers in the AG:
1540 * SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3.
1541 */
1542#define	XFS_BNO_BLOCK(mp)	((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1))
1543#define	XFS_CNT_BLOCK(mp)	((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))
1544
1545
1546/*
1547 * Inode Allocation Btree format definitions
1548 *
1549 * There is a btree for the inode map per allocation group.
1550 */
1551#define	XFS_IBT_MAGIC		0x49414254	/* 'IABT' */
1552#define	XFS_IBT_CRC_MAGIC	0x49414233	/* 'IAB3' */
1553#define	XFS_FIBT_MAGIC		0x46494254	/* 'FIBT' */
1554#define	XFS_FIBT_CRC_MAGIC	0x46494233	/* 'FIB3' */
1555
1556typedef uint64_t	xfs_inofree_t;
1557#define	XFS_INODES_PER_CHUNK		(NBBY * sizeof(xfs_inofree_t))
1558#define	XFS_INODES_PER_CHUNK_LOG	(XFS_NBBYLOG + 3)
1559#define	XFS_INOBT_ALL_FREE		((xfs_inofree_t)-1)
1560#define	XFS_INOBT_MASK(i)		((xfs_inofree_t)1 << (i))
1561
1562#define XFS_INOBT_HOLEMASK_FULL		0	/* holemask for full chunk */
1563#define XFS_INOBT_HOLEMASK_BITS		(NBBY * sizeof(uint16_t))
1564#define XFS_INODES_PER_HOLEMASK_BIT	\
1565	(XFS_INODES_PER_CHUNK / (NBBY * sizeof(uint16_t)))
1566
1567static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
1568{
1569	return ((n >= XFS_INODES_PER_CHUNK ? 0 : XFS_INOBT_MASK(n)) - 1) << i;
1570}
1571
1572/*
1573 * The on-disk inode record structure has two formats. The original "full"
1574 * format uses a 4-byte freecount. The "sparse" format uses a 1-byte freecount
1575 * and replaces the 3 high-order freecount bytes wth the holemask and inode
1576 * count.
1577 *
1578 * The holemask of the sparse record format allows an inode chunk to have holes
1579 * that refer to blocks not owned by the inode record. This facilitates inode
1580 * allocation in the event of severe free space fragmentation.
1581 */
1582typedef struct xfs_inobt_rec {
1583	__be32		ir_startino;	/* starting inode number */
1584	union {
1585		struct {
1586			__be32	ir_freecount;	/* count of free inodes */
1587		} f;
1588		struct {
1589			__be16	ir_holemask;/* hole mask for sparse chunks */
1590			__u8	ir_count;	/* total inode count */
1591			__u8	ir_freecount;	/* count of free inodes */
1592		} sp;
1593	} ir_u;
1594	__be64		ir_free;	/* free inode mask */
1595} xfs_inobt_rec_t;
1596
1597typedef struct xfs_inobt_rec_incore {
1598	xfs_agino_t	ir_startino;	/* starting inode number */
1599	uint16_t	ir_holemask;	/* hole mask for sparse chunks */
1600	uint8_t		ir_count;	/* total inode count */
1601	uint8_t		ir_freecount;	/* count of free inodes (set bits) */
1602	xfs_inofree_t	ir_free;	/* free inode mask */
1603} xfs_inobt_rec_incore_t;
1604
1605static inline bool xfs_inobt_issparse(uint16_t holemask)
1606{
1607	/* non-zero holemask represents a sparse rec. */
1608	return holemask;
1609}
1610
1611/*
1612 * Key structure
1613 */
1614typedef struct xfs_inobt_key {
1615	__be32		ir_startino;	/* starting inode number */
1616} xfs_inobt_key_t;
1617
1618/* btree pointer type */
1619typedef __be32 xfs_inobt_ptr_t;
1620
1621/*
1622 * block numbers in the AG.
1623 */
1624#define	XFS_IBT_BLOCK(mp)		((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1))
1625#define	XFS_FIBT_BLOCK(mp)		((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))
1626
1627/*
1628 * Reverse mapping btree format definitions
1629 *
1630 * There is a btree for the reverse map per allocation group
1631 */
1632#define	XFS_RMAP_CRC_MAGIC	0x524d4233	/* 'RMB3' */
1633
1634/*
1635 * Ownership info for an extent.  This is used to create reverse-mapping
1636 * entries.
1637 */
1638#define XFS_OWNER_INFO_ATTR_FORK	(1 << 0)
1639#define XFS_OWNER_INFO_BMBT_BLOCK	(1 << 1)
1640struct xfs_owner_info {
1641	uint64_t		oi_owner;
1642	xfs_fileoff_t		oi_offset;
1643	unsigned int		oi_flags;
1644};
1645
1646/*
1647 * Special owner types.
1648 *
1649 * Seeing as we only support up to 8EB, we have the upper bit of the owner field
1650 * to tell us we have a special owner value. We use these for static metadata
1651 * allocated at mkfs/growfs time, as well as for freespace management metadata.
1652 */
1653#define XFS_RMAP_OWN_NULL	(-1ULL)	/* No owner, for growfs */
1654#define XFS_RMAP_OWN_UNKNOWN	(-2ULL)	/* Unknown owner, for EFI recovery */
1655#define XFS_RMAP_OWN_FS		(-3ULL)	/* static fs metadata */
1656#define XFS_RMAP_OWN_LOG	(-4ULL)	/* static fs metadata */
1657#define XFS_RMAP_OWN_AG		(-5ULL)	/* AG freespace btree blocks */
1658#define XFS_RMAP_OWN_INOBT	(-6ULL)	/* Inode btree blocks */
1659#define XFS_RMAP_OWN_INODES	(-7ULL)	/* Inode chunk */
1660#define XFS_RMAP_OWN_REFC	(-8ULL) /* refcount tree */
1661#define XFS_RMAP_OWN_COW	(-9ULL) /* cow allocations */
1662#define XFS_RMAP_OWN_MIN	(-10ULL) /* guard */
1663
1664#define XFS_RMAP_NON_INODE_OWNER(owner)	(!!((owner) & (1ULL << 63)))
1665
1666/*
1667 * Data record structure
1668 */
1669struct xfs_rmap_rec {
1670	__be32		rm_startblock;	/* extent start block */
1671	__be32		rm_blockcount;	/* extent length */
1672	__be64		rm_owner;	/* extent owner */
1673	__be64		rm_offset;	/* offset within the owner */
1674};
1675
1676/*
1677 * rmap btree record
1678 *  rm_offset:63 is the attribute fork flag
1679 *  rm_offset:62 is the bmbt block flag
1680 *  rm_offset:61 is the unwritten extent flag (same as l0:63 in bmbt)
1681 *  rm_offset:54-60 aren't used and should be zero
1682 *  rm_offset:0-53 is the block offset within the inode
1683 */
1684#define XFS_RMAP_OFF_ATTR_FORK	((uint64_t)1ULL << 63)
1685#define XFS_RMAP_OFF_BMBT_BLOCK	((uint64_t)1ULL << 62)
1686#define XFS_RMAP_OFF_UNWRITTEN	((uint64_t)1ULL << 61)
1687
1688#define XFS_RMAP_LEN_MAX	((uint32_t)~0U)
1689#define XFS_RMAP_OFF_FLAGS	(XFS_RMAP_OFF_ATTR_FORK | \
1690				 XFS_RMAP_OFF_BMBT_BLOCK | \
1691				 XFS_RMAP_OFF_UNWRITTEN)
1692#define XFS_RMAP_OFF_MASK	((uint64_t)0x3FFFFFFFFFFFFFULL)
1693
1694#define XFS_RMAP_OFF(off)		((off) & XFS_RMAP_OFF_MASK)
1695
1696#define XFS_RMAP_IS_BMBT_BLOCK(off)	(!!((off) & XFS_RMAP_OFF_BMBT_BLOCK))
1697#define XFS_RMAP_IS_ATTR_FORK(off)	(!!((off) & XFS_RMAP_OFF_ATTR_FORK))
1698#define XFS_RMAP_IS_UNWRITTEN(len)	(!!((off) & XFS_RMAP_OFF_UNWRITTEN))
1699
1700#define RMAPBT_STARTBLOCK_BITLEN	32
1701#define RMAPBT_BLOCKCOUNT_BITLEN	32
1702#define RMAPBT_OWNER_BITLEN		64
1703#define RMAPBT_ATTRFLAG_BITLEN		1
1704#define RMAPBT_BMBTFLAG_BITLEN		1
1705#define RMAPBT_EXNTFLAG_BITLEN		1
1706#define RMAPBT_UNUSED_OFFSET_BITLEN	7
1707#define RMAPBT_OFFSET_BITLEN		54
1708
1709/*
1710 * Key structure
1711 *
1712 * We don't use the length for lookups
1713 */
1714struct xfs_rmap_key {
1715	__be32		rm_startblock;	/* extent start block */
1716	__be64		rm_owner;	/* extent owner */
1717	__be64		rm_offset;	/* offset within the owner */
1718} __attribute__((packed));
1719
1720/* btree pointer type */
1721typedef __be32 xfs_rmap_ptr_t;
1722
1723#define	XFS_RMAP_BLOCK(mp) \
1724	(xfs_has_finobt(((mp))) ? \
1725	 XFS_FIBT_BLOCK(mp) + 1 : \
1726	 XFS_IBT_BLOCK(mp) + 1)
1727
1728/*
1729 * Reference Count Btree format definitions
1730 *
1731 */
1732#define	XFS_REFC_CRC_MAGIC	0x52334643	/* 'R3FC' */
1733
1734unsigned int xfs_refc_block(struct xfs_mount *mp);
1735
1736/*
1737 * Data record/key structure
1738 *
1739 * Each record associates a range of physical blocks (starting at
1740 * rc_startblock and ending rc_blockcount blocks later) with a reference
1741 * count (rc_refcount).  Extents that are being used to stage a copy on
1742 * write (CoW) operation are recorded in the refcount btree with a
1743 * refcount of 1.  All other records must have a refcount > 1 and must
1744 * track an extent mapped only by file data forks.
1745 *
1746 * Extents with a single owner (attributes, metadata, non-shared file
1747 * data) are not tracked here.  Free space is also not tracked here.
1748 * This is consistent with pre-reflink XFS.
1749 */
1750
1751/*
1752 * Extents that are being used to stage a copy on write are stored
1753 * in the refcount btree with a refcount of 1 and the upper bit set
1754 * on the startblock.  This speeds up mount time deletion of stale
1755 * staging extents because they're all at the right side of the tree.
1756 */
1757#define XFS_REFC_COWFLAG		(1U << 31)
1758#define REFCNTBT_COWFLAG_BITLEN		1
1759#define REFCNTBT_AGBLOCK_BITLEN		31
1760
1761struct xfs_refcount_rec {
1762	__be32		rc_startblock;	/* starting block number */
1763	__be32		rc_blockcount;	/* count of blocks */
1764	__be32		rc_refcount;	/* number of inodes linked here */
1765};
1766
1767struct xfs_refcount_key {
1768	__be32		rc_startblock;	/* starting block number */
1769};
1770
1771#define MAXREFCOUNT	((xfs_nlink_t)~0U)
1772#define MAXREFCEXTLEN	((xfs_extlen_t)~0U)
1773
1774/* btree pointer type */
1775typedef __be32 xfs_refcount_ptr_t;
1776
1777
1778/*
1779 * BMAP Btree format definitions
1780 *
1781 * This includes both the root block definition that sits inside an inode fork
1782 * and the record/pointer formats for the leaf/node in the blocks.
1783 */
1784#define XFS_BMAP_MAGIC		0x424d4150	/* 'BMAP' */
1785#define XFS_BMAP_CRC_MAGIC	0x424d4133	/* 'BMA3' */
1786
1787/*
1788 * Bmap root header, on-disk form only.
1789 */
1790typedef struct xfs_bmdr_block {
1791	__be16		bb_level;	/* 0 is a leaf */
1792	__be16		bb_numrecs;	/* current # of data records */
1793} xfs_bmdr_block_t;
1794
1795/*
1796 * Bmap btree record and extent descriptor.
1797 *  l0:63 is an extent flag (value 1 indicates non-normal).
1798 *  l0:9-62 are startoff.
1799 *  l0:0-8 and l1:21-63 are startblock.
1800 *  l1:0-20 are blockcount.
1801 */
1802#define BMBT_EXNTFLAG_BITLEN	1
1803#define BMBT_STARTOFF_BITLEN	54
1804#define BMBT_STARTBLOCK_BITLEN	52
1805#define BMBT_BLOCKCOUNT_BITLEN	21
1806
1807#define BMBT_STARTOFF_MASK	((1ULL << BMBT_STARTOFF_BITLEN) - 1)
1808#define BMBT_BLOCKCOUNT_MASK	((1ULL << BMBT_BLOCKCOUNT_BITLEN) - 1)
1809
1810#define XFS_MAX_BMBT_EXTLEN	((xfs_extlen_t)(BMBT_BLOCKCOUNT_MASK))
1811
1812/*
1813 * bmbt records have a file offset (block) field that is 54 bits wide, so this
1814 * is the largest xfs_fileoff_t that we ever expect to see.
1815 */
1816#define XFS_MAX_FILEOFF		(BMBT_STARTOFF_MASK + BMBT_BLOCKCOUNT_MASK)
1817
1818typedef struct xfs_bmbt_rec {
1819	__be64			l0, l1;
1820} xfs_bmbt_rec_t;
1821
1822typedef uint64_t	xfs_bmbt_rec_base_t;	/* use this for casts */
1823typedef xfs_bmbt_rec_t xfs_bmdr_rec_t;
1824
1825/*
1826 * Values and macros for delayed-allocation startblock fields.
1827 */
1828#define STARTBLOCKVALBITS	17
1829#define STARTBLOCKMASKBITS	(15 + 20)
1830#define STARTBLOCKMASK		\
1831	(((((xfs_fsblock_t)1) << STARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
1832
1833static inline int isnullstartblock(xfs_fsblock_t x)
1834{
1835	return ((x) & STARTBLOCKMASK) == STARTBLOCKMASK;
1836}
1837
1838static inline xfs_fsblock_t nullstartblock(int k)
1839{
1840	ASSERT(k < (1 << STARTBLOCKVALBITS));
1841	return STARTBLOCKMASK | (k);
1842}
1843
1844static inline xfs_filblks_t startblockval(xfs_fsblock_t x)
1845{
1846	return (xfs_filblks_t)((x) & ~STARTBLOCKMASK);
1847}
1848
1849/*
1850 * Key structure for non-leaf levels of the tree.
1851 */
1852typedef struct xfs_bmbt_key {
1853	__be64		br_startoff;	/* starting file offset */
1854} xfs_bmbt_key_t, xfs_bmdr_key_t;
1855
1856/* btree pointer type */
1857typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t;
1858
1859
1860/*
1861 * Generic Btree block format definitions
1862 *
1863 * This is a combination of the actual format used on disk for short and long
1864 * format btrees.  The first three fields are shared by both format, but the
1865 * pointers are different and should be used with care.
1866 *
1867 * To get the size of the actual short or long form headers please use the size
1868 * macros below.  Never use sizeof(xfs_btree_block).
1869 *
1870 * The blkno, crc, lsn, owner and uuid fields are only available in filesystems
1871 * with the crc feature bit, and all accesses to them must be conditional on
1872 * that flag.
1873 */
1874/* short form block header */
1875struct xfs_btree_block_shdr {
1876	__be32		bb_leftsib;
1877	__be32		bb_rightsib;
1878
1879	__be64		bb_blkno;
1880	__be64		bb_lsn;
1881	uuid_t		bb_uuid;
1882	__be32		bb_owner;
1883	__le32		bb_crc;
1884};
1885
1886/* long form block header */
1887struct xfs_btree_block_lhdr {
1888	__be64		bb_leftsib;
1889	__be64		bb_rightsib;
1890
1891	__be64		bb_blkno;
1892	__be64		bb_lsn;
1893	uuid_t		bb_uuid;
1894	__be64		bb_owner;
1895	__le32		bb_crc;
1896	__be32		bb_pad; /* padding for alignment */
1897};
1898
1899struct xfs_btree_block {
1900	__be32		bb_magic;	/* magic number for block type */
1901	__be16		bb_level;	/* 0 is a leaf */
1902	__be16		bb_numrecs;	/* current # of data records */
1903	union {
1904		struct xfs_btree_block_shdr s;
1905		struct xfs_btree_block_lhdr l;
1906	} bb_u;				/* rest */
1907};
1908
1909/* size of a short form block */
1910#define XFS_BTREE_SBLOCK_LEN \
1911	(offsetof(struct xfs_btree_block, bb_u) + \
1912	 offsetof(struct xfs_btree_block_shdr, bb_blkno))
1913/* size of a long form block */
1914#define XFS_BTREE_LBLOCK_LEN \
1915	(offsetof(struct xfs_btree_block, bb_u) + \
1916	 offsetof(struct xfs_btree_block_lhdr, bb_blkno))
1917
1918/* sizes of CRC enabled btree blocks */
1919#define XFS_BTREE_SBLOCK_CRC_LEN \
1920	(offsetof(struct xfs_btree_block, bb_u) + \
1921	 sizeof(struct xfs_btree_block_shdr))
1922#define XFS_BTREE_LBLOCK_CRC_LEN \
1923	(offsetof(struct xfs_btree_block, bb_u) + \
1924	 sizeof(struct xfs_btree_block_lhdr))
1925
1926#define XFS_BTREE_SBLOCK_CRC_OFF \
1927	offsetof(struct xfs_btree_block, bb_u.s.bb_crc)
1928#define XFS_BTREE_LBLOCK_CRC_OFF \
1929	offsetof(struct xfs_btree_block, bb_u.l.bb_crc)
1930
1931/*
1932 * On-disk XFS access control list structure.
1933 */
1934struct xfs_acl_entry {
1935	__be32	ae_tag;
1936	__be32	ae_id;
1937	__be16	ae_perm;
1938	__be16	ae_pad;		/* fill the implicit hole in the structure */
1939};
1940
1941struct xfs_acl {
1942	__be32			acl_cnt;
1943	struct xfs_acl_entry	acl_entry[];
1944};
1945
1946/*
1947 * The number of ACL entries allowed is defined by the on-disk format.
1948 * For v4 superblocks, that is limited to 25 entries. For v5 superblocks, it is
1949 * limited only by the maximum size of the xattr that stores the information.
1950 */
1951#define XFS_ACL_MAX_ENTRIES(mp)	\
1952	(xfs_has_crc(mp) \
1953		?  (XFS_XATTR_SIZE_MAX - sizeof(struct xfs_acl)) / \
1954						sizeof(struct xfs_acl_entry) \
1955		: 25)
1956
1957#define XFS_ACL_SIZE(cnt) \
1958	(sizeof(struct xfs_acl) + \
1959		sizeof(struct xfs_acl_entry) * cnt)
1960
1961#define XFS_ACL_MAX_SIZE(mp) \
1962	XFS_ACL_SIZE(XFS_ACL_MAX_ENTRIES((mp)))
1963
1964
1965/* On-disk XFS extended attribute names */
1966#define SGI_ACL_FILE		"SGI_ACL_FILE"
1967#define SGI_ACL_DEFAULT		"SGI_ACL_DEFAULT"
1968#define SGI_ACL_FILE_SIZE	(sizeof(SGI_ACL_FILE)-1)
1969#define SGI_ACL_DEFAULT_SIZE	(sizeof(SGI_ACL_DEFAULT)-1)
1970
1971#endif /* __XFS_FORMAT_H__ */