/* * Copyright (c) 2000-2005 Silicon Graphics, Inc. * All Rights Reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation. * * This program is distributed in the hope that it would be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef __XFS_FORMAT_H__ #define __XFS_FORMAT_H__ /* * XFS On Disk Format Definitions * * This header file defines all the on-disk format definitions for * general XFS objects. Directory and attribute related objects are defined in * xfs_da_format.h, which log and log item formats are defined in * xfs_log_format.h. Everything else goes here. */ struct xfs_mount; struct xfs_trans; struct xfs_inode; struct xfs_buf; struct xfs_ifork; typedef struct xfs_timestamp { __be32 t_sec; /* timestamp seconds */ __be32 t_nsec; /* timestamp nanoseconds */ } xfs_timestamp_t; /* * On-disk inode structure. * * This is just the header or "dinode core", the inode is expanded to fill a * variable size the leftover area split into a data and an attribute fork. * The format of the data and attribute fork depends on the format of the * inode as indicated by di_format and di_aformat. To access the data and * attribute use the XFS_DFORK_DPTR, XFS_DFORK_APTR, and XFS_DFORK_PTR macros * below. * * There is a very similar struct icdinode in xfs_inode which matches the * layout of the first 96 bytes of this structure, but is kept in native * format instead of big endian. * * Note: di_flushiter is only used by v1/2 inodes - it's effectively a zeroed * padding field for v3 inodes. */ #define XFS_DINODE_MAGIC 0x494e /* 'IN' */ #define XFS_DINODE_GOOD_VERSION(v) ((v) >= 1 && (v) <= 3) typedef struct xfs_dinode { __be16 di_magic; /* inode magic # = XFS_DINODE_MAGIC */ __be16 di_mode; /* mode and type of file */ __u8 di_version; /* inode version */ __u8 di_format; /* format of di_c data */ __be16 di_onlink; /* old number of links to file */ __be32 di_uid; /* owner's user id */ __be32 di_gid; /* owner's group id */ __be32 di_nlink; /* number of links to file */ __be16 di_projid_lo; /* lower part of owner's project id */ __be16 di_projid_hi; /* higher part owner's project id */ __u8 di_pad[6]; /* unused, zeroed space */ __be16 di_flushiter; /* incremented on flush */ xfs_timestamp_t di_atime; /* time last accessed */ xfs_timestamp_t di_mtime; /* time last modified */ xfs_timestamp_t di_ctime; /* time created/inode modified */ __be64 di_size; /* number of bytes in file */ __be64 di_nblocks; /* # of direct & btree blocks used */ __be32 di_extsize; /* basic/minimum extent size for file */ __be32 di_nextents; /* number of extents in data fork */ __be16 di_anextents; /* number of extents in attribute fork*/ __u8 di_forkoff; /* attr fork offs, <<3 for 64b align */ __s8 di_aformat; /* format of attr fork's data */ __be32 di_dmevmask; /* DMIG event mask */ __be16 di_dmstate; /* DMIG state info */ __be16 di_flags; /* random flags, XFS_DIFLAG_... */ __be32 di_gen; /* generation number */ /* di_next_unlinked is the only non-core field in the old dinode */ __be32 di_next_unlinked;/* agi unlinked list ptr */ /* start of the extended dinode, writable fields */ __le32 di_crc; /* CRC of the inode */ __be64 di_changecount; /* number of attribute changes */ __be64 di_lsn; /* flush sequence */ __be64 di_flags2; /* more random flags */ __u8 di_pad2[16]; /* more padding for future expansion */ /* fields only written to during inode creation */ xfs_timestamp_t di_crtime; /* time created */ __be64 di_ino; /* inode number */ uuid_t di_uuid; /* UUID of the filesystem */ /* structure must be padded to 64 bit alignment */ } xfs_dinode_t; #define XFS_DINODE_CRC_OFF offsetof(struct xfs_dinode, di_crc) #define DI_MAX_FLUSH 0xffff /* * Size of the core inode on disk. Version 1 and 2 inodes have * the same size, but version 3 has grown a few additional fields. */ static inline uint xfs_dinode_size(int version) { if (version == 3) return sizeof(struct xfs_dinode); return offsetof(struct xfs_dinode, di_crc); } /* * The 32 bit link count in the inode theoretically maxes out at UINT_MAX. * Since the pathconf interface is signed, we use 2^31 - 1 instead. * The old inode format had a 16 bit link count, so its maximum is USHRT_MAX. */ #define XFS_MAXLINK ((1U << 31) - 1U) #define XFS_MAXLINK_1 65535U /* * Values for di_format */ typedef enum xfs_dinode_fmt { XFS_DINODE_FMT_DEV, /* xfs_dev_t */ XFS_DINODE_FMT_LOCAL, /* bulk data */ XFS_DINODE_FMT_EXTENTS, /* struct xfs_bmbt_rec */ XFS_DINODE_FMT_BTREE, /* struct xfs_bmdr_block */ XFS_DINODE_FMT_UUID /* uuid_t */ } xfs_dinode_fmt_t; /* * Inode minimum and maximum sizes. */ #define XFS_DINODE_MIN_LOG 8 #define XFS_DINODE_MAX_LOG 11 #define XFS_DINODE_MIN_SIZE (1 << XFS_DINODE_MIN_LOG) #define XFS_DINODE_MAX_SIZE (1 << XFS_DINODE_MAX_LOG) /* * Inode size for given fs. */ #define XFS_LITINO(mp, version) \ ((int)(((mp)->m_sb.sb_inodesize) - xfs_dinode_size(version))) /* * Inode data & attribute fork sizes, per inode. */ #define XFS_DFORK_Q(dip) ((dip)->di_forkoff != 0) #define XFS_DFORK_BOFF(dip) ((int)((dip)->di_forkoff << 3)) #define XFS_DFORK_DSIZE(dip,mp) \ (XFS_DFORK_Q(dip) ? \ XFS_DFORK_BOFF(dip) : \ XFS_LITINO(mp, (dip)->di_version)) #define XFS_DFORK_ASIZE(dip,mp) \ (XFS_DFORK_Q(dip) ? \ XFS_LITINO(mp, (dip)->di_version) - XFS_DFORK_BOFF(dip) : \ 0) #define XFS_DFORK_SIZE(dip,mp,w) \ ((w) == XFS_DATA_FORK ? \ XFS_DFORK_DSIZE(dip, mp) : \ XFS_DFORK_ASIZE(dip, mp)) /* * Return pointers to the data or attribute forks. */ #define XFS_DFORK_DPTR(dip) \ ((char *)dip + xfs_dinode_size(dip->di_version)) #define XFS_DFORK_APTR(dip) \ (XFS_DFORK_DPTR(dip) + XFS_DFORK_BOFF(dip)) #define XFS_DFORK_PTR(dip,w) \ ((w) == XFS_DATA_FORK ? XFS_DFORK_DPTR(dip) : XFS_DFORK_APTR(dip)) #define XFS_DFORK_FORMAT(dip,w) \ ((w) == XFS_DATA_FORK ? \ (dip)->di_format : \ (dip)->di_aformat) #define XFS_DFORK_NEXTENTS(dip,w) \ ((w) == XFS_DATA_FORK ? \ be32_to_cpu((dip)->di_nextents) : \ be16_to_cpu((dip)->di_anextents)) /* * For block and character special files the 32bit dev_t is stored at the * beginning of the data fork. */ static inline xfs_dev_t xfs_dinode_get_rdev(struct xfs_dinode *dip) { return be32_to_cpu(*(__be32 *)XFS_DFORK_DPTR(dip)); } static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev) { *(__be32 *)XFS_DFORK_DPTR(dip) = cpu_to_be32(rdev); } /* * Values for di_flags * There should be a one-to-one correspondence between these flags and the * XFS_XFLAG_s. */ #define XFS_DIFLAG_REALTIME_BIT 0 /* file's blocks come from rt area */ #define XFS_DIFLAG_PREALLOC_BIT 1 /* file space has been preallocated */ #define XFS_DIFLAG_NEWRTBM_BIT 2 /* for rtbitmap inode, new format */ #define XFS_DIFLAG_IMMUTABLE_BIT 3 /* inode is immutable */ #define XFS_DIFLAG_APPEND_BIT 4 /* inode is append-only */ #define XFS_DIFLAG_SYNC_BIT 5 /* inode is written synchronously */ #define XFS_DIFLAG_NOATIME_BIT 6 /* do not update atime */ #define XFS_DIFLAG_NODUMP_BIT 7 /* do not dump */ #define XFS_DIFLAG_RTINHERIT_BIT 8 /* create with realtime bit set */ #define XFS_DIFLAG_PROJINHERIT_BIT 9 /* create with parents projid */ #define XFS_DIFLAG_NOSYMLINKS_BIT 10 /* disallow symlink creation */ #define XFS_DIFLAG_EXTSIZE_BIT 11 /* inode extent size allocator hint */ #define XFS_DIFLAG_EXTSZINHERIT_BIT 12 /* inherit inode extent size */ #define XFS_DIFLAG_NODEFRAG_BIT 13 /* do not reorganize/defragment */ #define XFS_DIFLAG_FILESTREAM_BIT 14 /* use filestream allocator */ #define XFS_DIFLAG_REALTIME (1 << XFS_DIFLAG_REALTIME_BIT) #define XFS_DIFLAG_PREALLOC (1 << XFS_DIFLAG_PREALLOC_BIT) #define XFS_DIFLAG_NEWRTBM (1 << XFS_DIFLAG_NEWRTBM_BIT) #define XFS_DIFLAG_IMMUTABLE (1 << XFS_DIFLAG_IMMUTABLE_BIT) #define XFS_DIFLAG_APPEND (1 << XFS_DIFLAG_APPEND_BIT) #define XFS_DIFLAG_SYNC (1 << XFS_DIFLAG_SYNC_BIT) #define XFS_DIFLAG_NOATIME (1 << XFS_DIFLAG_NOATIME_BIT) #define XFS_DIFLAG_NODUMP (1 << XFS_DIFLAG_NODUMP_BIT) #define XFS_DIFLAG_RTINHERIT (1 << XFS_DIFLAG_RTINHERIT_BIT) #define XFS_DIFLAG_PROJINHERIT (1 << XFS_DIFLAG_PROJINHERIT_BIT) #define XFS_DIFLAG_NOSYMLINKS (1 << XFS_DIFLAG_NOSYMLINKS_BIT) #define XFS_DIFLAG_EXTSIZE (1 << XFS_DIFLAG_EXTSIZE_BIT) #define XFS_DIFLAG_EXTSZINHERIT (1 << XFS_DIFLAG_EXTSZINHERIT_BIT) #define XFS_DIFLAG_NODEFRAG (1 << XFS_DIFLAG_NODEFRAG_BIT) #define XFS_DIFLAG_FILESTREAM (1 << XFS_DIFLAG_FILESTREAM_BIT) #define XFS_DIFLAG_ANY \ (XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \ XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \ XFS_DIFLAG_NOATIME | XFS_DIFLAG_NODUMP | XFS_DIFLAG_RTINHERIT | \ XFS_DIFLAG_PROJINHERIT | XFS_DIFLAG_NOSYMLINKS | XFS_DIFLAG_EXTSIZE | \ XFS_DIFLAG_EXTSZINHERIT | XFS_DIFLAG_NODEFRAG | XFS_DIFLAG_FILESTREAM) /* * RealTime Device format definitions */ /* Min and max rt extent sizes, specified in bytes */ #define XFS_MAX_RTEXTSIZE (1024 * 1024 * 1024) /* 1GB */ #define XFS_DFL_RTEXTSIZE (64 * 1024) /* 64kB */ #define XFS_MIN_RTEXTSIZE (4 * 1024) /* 4kB */ #define XFS_BLOCKSIZE(mp) ((mp)->m_sb.sb_blocksize) #define XFS_BLOCKMASK(mp) ((mp)->m_blockmask) #define XFS_BLOCKWSIZE(mp) ((mp)->m_blockwsize) #define XFS_BLOCKWMASK(mp) ((mp)->m_blockwmask) /* * RT Summary and bit manipulation macros. */ #define XFS_SUMOFFS(mp,ls,bb) ((int)((ls) * (mp)->m_sb.sb_rbmblocks + (bb))) #define XFS_SUMOFFSTOBLOCK(mp,s) \ (((s) * (uint)sizeof(xfs_suminfo_t)) >> (mp)->m_sb.sb_blocklog) #define XFS_SUMPTR(mp,bp,so) \ ((xfs_suminfo_t *)((bp)->b_addr + \ (((so) * (uint)sizeof(xfs_suminfo_t)) & XFS_BLOCKMASK(mp)))) #define XFS_BITTOBLOCK(mp,bi) ((bi) >> (mp)->m_blkbit_log) #define XFS_BLOCKTOBIT(mp,bb) ((bb) << (mp)->m_blkbit_log) #define XFS_BITTOWORD(mp,bi) \ ((int)(((bi) >> XFS_NBWORDLOG) & XFS_BLOCKWMASK(mp))) #define XFS_RTMIN(a,b) ((a) < (b) ? (a) : (b)) #define XFS_RTMAX(a,b) ((a) > (b) ? (a) : (b)) #define XFS_RTLOBIT(w) xfs_lowbit32(w) #define XFS_RTHIBIT(w) xfs_highbit32(w) #define XFS_RTBLOCKLOG(b) xfs_highbit64(b) /* * Dquot and dquot block format definitions */ #define XFS_DQUOT_MAGIC 0x4451 /* 'DQ' */ #define XFS_DQUOT_VERSION (u_int8_t)0x01 /* latest version number */ /* * This is the main portion of the on-disk representation of quota * information for a user. This is the q_core of the xfs_dquot_t that * is kept in kernel memory. We pad this with some more expansion room * to construct the on disk structure. */ typedef struct xfs_disk_dquot { __be16 d_magic; /* dquot magic = XFS_DQUOT_MAGIC */ __u8 d_version; /* dquot version */ __u8 d_flags; /* XFS_DQ_USER/PROJ/GROUP */ __be32 d_id; /* user,project,group id */ __be64 d_blk_hardlimit;/* absolute limit on disk blks */ __be64 d_blk_softlimit;/* preferred limit on disk blks */ __be64 d_ino_hardlimit;/* maximum # allocated inodes */ __be64 d_ino_softlimit;/* preferred inode limit */ __be64 d_bcount; /* disk blocks owned by the user */ __be64 d_icount; /* inodes owned by the user */ __be32 d_itimer; /* zero if within inode limits if not, this is when we refuse service */ __be32 d_btimer; /* similar to above; for disk blocks */ __be16 d_iwarns; /* warnings issued wrt num inodes */ __be16 d_bwarns; /* warnings issued wrt disk blocks */ __be32 d_pad0; /* 64 bit align */ __be64 d_rtb_hardlimit;/* absolute limit on realtime blks */ __be64 d_rtb_softlimit;/* preferred limit on RT disk blks */ __be64 d_rtbcount; /* realtime blocks owned */ __be32 d_rtbtimer; /* similar to above; for RT disk blocks */ __be16 d_rtbwarns; /* warnings issued wrt RT disk blocks */ __be16 d_pad; } xfs_disk_dquot_t; /* * This is what goes on disk. This is separated from the xfs_disk_dquot because * carrying the unnecessary padding would be a waste of memory. */ typedef struct xfs_dqblk { xfs_disk_dquot_t dd_diskdq; /* portion that lives incore as well */ char dd_fill[4]; /* filling for posterity */ /* * These two are only present on filesystems with the CRC bits set. */ __be32 dd_crc; /* checksum */ __be64 dd_lsn; /* last modification in log */ uuid_t dd_uuid; /* location information */ } xfs_dqblk_t; #define XFS_DQUOT_CRC_OFF offsetof(struct xfs_dqblk, dd_crc) /* * Remote symlink format and access functions. */ #define XFS_SYMLINK_MAGIC 0x58534c4d /* XSLM */ struct xfs_dsymlink_hdr { __be32 sl_magic; __be32 sl_offset; __be32 sl_bytes; __be32 sl_crc; uuid_t sl_uuid; __be64 sl_owner; __be64 sl_blkno; __be64 sl_lsn; }; #define XFS_SYMLINK_CRC_OFF offsetof(struct xfs_dsymlink_hdr, sl_crc) /* * The maximum pathlen is 1024 bytes. Since the minimum file system * blocksize is 512 bytes, we can get a max of 3 extents back from * bmapi when crc headers are taken into account. */ #define XFS_SYMLINK_MAPS 3 #define XFS_SYMLINK_BUF_SPACE(mp, bufsize) \ ((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \ sizeof(struct xfs_dsymlink_hdr) : 0)) /* * Allocation Btree format definitions * * There are two on-disk btrees, one sorted by blockno and one sorted * by blockcount and blockno. All blocks look the same to make the code * simpler; if we have time later, we'll make the optimizations. */ #define XFS_ABTB_MAGIC 0x41425442 /* 'ABTB' for bno tree */ #define XFS_ABTB_CRC_MAGIC 0x41423342 /* 'AB3B' */ #define XFS_ABTC_MAGIC 0x41425443 /* 'ABTC' for cnt tree */ #define XFS_ABTC_CRC_MAGIC 0x41423343 /* 'AB3C' */ /* * Data record/key structure */ typedef struct xfs_alloc_rec { __be32 ar_startblock; /* starting block number */ __be32 ar_blockcount; /* count of free blocks */ } xfs_alloc_rec_t, xfs_alloc_key_t; typedef struct xfs_alloc_rec_incore { xfs_agblock_t ar_startblock; /* starting block number */ xfs_extlen_t ar_blockcount; /* count of free blocks */ } xfs_alloc_rec_incore_t; /* btree pointer type */ typedef __be32 xfs_alloc_ptr_t; /* * Block numbers in the AG: * SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3. */ #define XFS_BNO_BLOCK(mp) ((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1)) #define XFS_CNT_BLOCK(mp) ((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1)) /* * Inode Allocation Btree format definitions * * There is a btree for the inode map per allocation group. */ #define XFS_IBT_MAGIC 0x49414254 /* 'IABT' */ #define XFS_IBT_CRC_MAGIC 0x49414233 /* 'IAB3' */ #define XFS_FIBT_MAGIC 0x46494254 /* 'FIBT' */ #define XFS_FIBT_CRC_MAGIC 0x46494233 /* 'FIB3' */ typedef __uint64_t xfs_inofree_t; #define XFS_INODES_PER_CHUNK (NBBY * sizeof(xfs_inofree_t)) #define XFS_INODES_PER_CHUNK_LOG (XFS_NBBYLOG + 3) #define XFS_INOBT_ALL_FREE ((xfs_inofree_t)-1) #define XFS_INOBT_MASK(i) ((xfs_inofree_t)1 << (i)) static inline xfs_inofree_t xfs_inobt_maskn(int i, int n) { return ((n >= XFS_INODES_PER_CHUNK ? 0 : XFS_INOBT_MASK(n)) - 1) << i; } /* * Data record structure */ typedef struct xfs_inobt_rec { __be32 ir_startino; /* starting inode number */ __be32 ir_freecount; /* count of free inodes (set bits) */ __be64 ir_free; /* free inode mask */ } xfs_inobt_rec_t; typedef struct xfs_inobt_rec_incore { xfs_agino_t ir_startino; /* starting inode number */ __int32_t ir_freecount; /* count of free inodes (set bits) */ xfs_inofree_t ir_free; /* free inode mask */ } xfs_inobt_rec_incore_t; /* * Key structure */ typedef struct xfs_inobt_key { __be32 ir_startino; /* starting inode number */ } xfs_inobt_key_t; /* btree pointer type */ typedef __be32 xfs_inobt_ptr_t; /* * block numbers in the AG. */ #define XFS_IBT_BLOCK(mp) ((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1)) #define XFS_FIBT_BLOCK(mp) ((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1)) /* * The first data block of an AG depends on whether the filesystem was formatted * with the finobt feature. If so, account for the finobt reserved root btree * block. */ #define XFS_PREALLOC_BLOCKS(mp) \ (xfs_sb_version_hasfinobt(&((mp)->m_sb)) ? \ XFS_FIBT_BLOCK(mp) + 1 : \ XFS_IBT_BLOCK(mp) + 1) /* * BMAP Btree format definitions * * This includes both the root block definition that sits inside an inode fork * and the record/pointer formats for the leaf/node in the blocks. */ #define XFS_BMAP_MAGIC 0x424d4150 /* 'BMAP' */ #define XFS_BMAP_CRC_MAGIC 0x424d4133 /* 'BMA3' */ /* * Bmap root header, on-disk form only. */ typedef struct xfs_bmdr_block { __be16 bb_level; /* 0 is a leaf */ __be16 bb_numrecs; /* current # of data records */ } xfs_bmdr_block_t; /* * Bmap btree record and extent descriptor. * l0:63 is an extent flag (value 1 indicates non-normal). * l0:9-62 are startoff. * l0:0-8 and l1:21-63 are startblock. * l1:0-20 are blockcount. */ #define BMBT_EXNTFLAG_BITLEN 1 #define BMBT_STARTOFF_BITLEN 54 #define BMBT_STARTBLOCK_BITLEN 52 #define BMBT_BLOCKCOUNT_BITLEN 21 typedef struct xfs_bmbt_rec { __be64 l0, l1; } xfs_bmbt_rec_t; typedef __uint64_t xfs_bmbt_rec_base_t; /* use this for casts */ typedef xfs_bmbt_rec_t xfs_bmdr_rec_t; typedef struct xfs_bmbt_rec_host { __uint64_t l0, l1; } xfs_bmbt_rec_host_t; /* * Values and macros for delayed-allocation startblock fields. */ #define STARTBLOCKVALBITS 17 #define STARTBLOCKMASKBITS (15 + 20) #define STARTBLOCKMASK \ (((((xfs_fsblock_t)1) << STARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS) static inline int isnullstartblock(xfs_fsblock_t x) { return ((x) & STARTBLOCKMASK) == STARTBLOCKMASK; } static inline xfs_fsblock_t nullstartblock(int k) { ASSERT(k < (1 << STARTBLOCKVALBITS)); return STARTBLOCKMASK | (k); } static inline xfs_filblks_t startblockval(xfs_fsblock_t x) { return (xfs_filblks_t)((x) & ~STARTBLOCKMASK); } /* * Possible extent formats. */ typedef enum { XFS_EXTFMT_NOSTATE = 0, XFS_EXTFMT_HASSTATE } xfs_exntfmt_t; /* * Possible extent states. */ typedef enum { XFS_EXT_NORM, XFS_EXT_UNWRITTEN, XFS_EXT_DMAPI_OFFLINE, XFS_EXT_INVALID } xfs_exntst_t; /* * Incore version of above. */ typedef struct xfs_bmbt_irec { xfs_fileoff_t br_startoff; /* starting file offset */ xfs_fsblock_t br_startblock; /* starting block number */ xfs_filblks_t br_blockcount; /* number of blocks */ xfs_exntst_t br_state; /* extent state */ } xfs_bmbt_irec_t; /* * Key structure for non-leaf levels of the tree. */ typedef struct xfs_bmbt_key { __be64 br_startoff; /* starting file offset */ } xfs_bmbt_key_t, xfs_bmdr_key_t; /* btree pointer type */ typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t; /* * Generic Btree block format definitions * * This is a combination of the actual format used on disk for short and long * format btrees. The first three fields are shared by both format, but the * pointers are different and should be used with care. * * To get the size of the actual short or long form headers please use the size * macros below. Never use sizeof(xfs_btree_block). * * The blkno, crc, lsn, owner and uuid fields are only available in filesystems * with the crc feature bit, and all accesses to them must be conditional on * that flag. */ struct xfs_btree_block { __be32 bb_magic; /* magic number for block type */ __be16 bb_level; /* 0 is a leaf */ __be16 bb_numrecs; /* current # of data records */ union { struct { __be32 bb_leftsib; __be32 bb_rightsib; __be64 bb_blkno; __be64 bb_lsn; uuid_t bb_uuid; __be32 bb_owner; __le32 bb_crc; } s; /* short form pointers */ struct { __be64 bb_leftsib; __be64 bb_rightsib; __be64 bb_blkno; __be64 bb_lsn; uuid_t bb_uuid; __be64 bb_owner; __le32 bb_crc; __be32 bb_pad; /* padding for alignment */ } l; /* long form pointers */ } bb_u; /* rest */ }; #define XFS_BTREE_SBLOCK_LEN 16 /* size of a short form block */ #define XFS_BTREE_LBLOCK_LEN 24 /* size of a long form block */ /* sizes of CRC enabled btree blocks */ #define XFS_BTREE_SBLOCK_CRC_LEN (XFS_BTREE_SBLOCK_LEN + 40) #define XFS_BTREE_LBLOCK_CRC_LEN (XFS_BTREE_LBLOCK_LEN + 48) #define XFS_BTREE_SBLOCK_CRC_OFF \ offsetof(struct xfs_btree_block, bb_u.s.bb_crc) #define XFS_BTREE_LBLOCK_CRC_OFF \ offsetof(struct xfs_btree_block, bb_u.l.bb_crc) #endif /* __XFS_FORMAT_H__ */