- 根目录:
- fs
- xfs
- xfs_format.h
/*
* 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;
/*
* 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)
#if XFS_BIG_BLKNOS
#define XFS_RTBLOCKLOG(b) xfs_highbit64(b)
#else
#define XFS_RTBLOCKLOG(b) xfs_highbit32(b)
#endif
/*
* 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;
};
/*
* 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' */
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_PREALLOC_BLOCKS(mp) ((xfs_agblock_t)(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 + XFS_BIG_BLKNOS * 20)
#define DSTARTBLOCKMASKBITS (15 + 20)
#define STARTBLOCKMASK \
(((((xfs_fsblock_t)1) << STARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
#define DSTARTBLOCKMASK \
(((((xfs_dfsbno_t)1) << DSTARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
static inline int isnullstartblock(xfs_fsblock_t x)
{
return ((x) & STARTBLOCKMASK) == STARTBLOCKMASK;
}
static inline int isnulldstartblock(xfs_dfsbno_t x)
{
return ((x) & DSTARTBLOCKMASK) == DSTARTBLOCKMASK;
}
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__ */