xfs_sb.h

linux 内核源代码

/*
 * 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_SB_H__
#define	__XFS_SB_H__

/*
 * Super block
 * Fits into a sector-sized buffer at address 0 of each allocation group.
 * Only the first of these is ever updated except during growfs.
 */

struct xfs_buf;
struct xfs_mount;

#define	XFS_SB_MAGIC		0x58465342	/* 'XFSB' */
#define	XFS_SB_VERSION_1	1		/* 5.3, 6.0.1, 6.1 */
#define	XFS_SB_VERSION_2	2		/* 6.2 - attributes */
#define	XFS_SB_VERSION_3	3		/* 6.2 - new inode version */
#define	XFS_SB_VERSION_4	4		/* 6.2+ - bitmask version */
#define	XFS_SB_VERSION_NUMBITS		0x000f
#define	XFS_SB_VERSION_ALLFBITS		0xfff0
#define	XFS_SB_VERSION_SASHFBITS	0xf000
#define	XFS_SB_VERSION_REALFBITS	0x0ff0
#define	XFS_SB_VERSION_ATTRBIT		0x0010
#define	XFS_SB_VERSION_NLINKBIT		0x0020
#define	XFS_SB_VERSION_QUOTABIT		0x0040
#define	XFS_SB_VERSION_ALIGNBIT		0x0080
#define	XFS_SB_VERSION_DALIGNBIT	0x0100
#define	XFS_SB_VERSION_SHAREDBIT	0x0200
#define XFS_SB_VERSION_LOGV2BIT		0x0400
#define XFS_SB_VERSION_SECTORBIT	0x0800
#define	XFS_SB_VERSION_EXTFLGBIT	0x1000
#define	XFS_SB_VERSION_DIRV2BIT		0x2000
#define	XFS_SB_VERSION_MOREBITSBIT	0x8000
#define	XFS_SB_VERSION_OKSASHFBITS	\
	(XFS_SB_VERSION_EXTFLGBIT | \
	 XFS_SB_VERSION_DIRV2BIT)
#define	XFS_SB_VERSION_OKREALFBITS	\
	(XFS_SB_VERSION_ATTRBIT | \
	 XFS_SB_VERSION_NLINKBIT | \
	 XFS_SB_VERSION_QUOTABIT | \
	 XFS_SB_VERSION_ALIGNBIT | \
	 XFS_SB_VERSION_DALIGNBIT | \
	 XFS_SB_VERSION_SHAREDBIT | \
	 XFS_SB_VERSION_LOGV2BIT | \
	 XFS_SB_VERSION_SECTORBIT | \
	 XFS_SB_VERSION_MOREBITSBIT)
#define	XFS_SB_VERSION_OKREALBITS	\
	(XFS_SB_VERSION_NUMBITS | \
	 XFS_SB_VERSION_OKREALFBITS | \
	 XFS_SB_VERSION_OKSASHFBITS)

/*
 * There are two words to hold XFS "feature" bits: the original
 * word, sb_versionnum, and sb_features2.  Whenever a bit is set in
 * sb_features2, the feature bit XFS_SB_VERSION_MOREBITSBIT must be set.
 *
 * These defines represent bits in sb_features2.
 */
#define XFS_SB_VERSION2_REALFBITS	0x00ffffff	/* Mask: features */
#define XFS_SB_VERSION2_RESERVED1BIT	0x00000001
#define XFS_SB_VERSION2_LAZYSBCOUNTBIT	0x00000002	/* Superblk counters */
#define XFS_SB_VERSION2_RESERVED4BIT	0x00000004
#define XFS_SB_VERSION2_ATTR2BIT	0x00000008	/* Inline attr rework */

#define	XFS_SB_VERSION2_OKREALFBITS	\
	(XFS_SB_VERSION2_LAZYSBCOUNTBIT	| \
	 XFS_SB_VERSION2_ATTR2BIT)
#define	XFS_SB_VERSION2_OKSASHFBITS	\
	(0)
#define XFS_SB_VERSION2_OKREALBITS	\
	(XFS_SB_VERSION2_OKREALFBITS |	\
	 XFS_SB_VERSION2_OKSASHFBITS )

/*
 * Superblock - in core version.  Must match the ondisk version below.
 */
typedef struct xfs_sb {
	__uint32_t	sb_magicnum;	/* magic number == XFS_SB_MAGIC */
	__uint32_t	sb_blocksize;	/* logical block size, bytes */
	xfs_drfsbno_t	sb_dblocks;	/* number of data blocks */
	xfs_drfsbno_t	sb_rblocks;	/* number of realtime blocks */
	xfs_drtbno_t	sb_rextents;	/* number of realtime extents */
	uuid_t		sb_uuid;	/* file system unique id */
	xfs_dfsbno_t	sb_logstart;	/* starting block of log if internal */
	xfs_ino_t	sb_rootino;	/* root inode number */
	xfs_ino_t	sb_rbmino;	/* bitmap inode for realtime extents */
	xfs_ino_t	sb_rsumino;	/* summary inode for rt bitmap */
	xfs_agblock_t	sb_rextsize;	/* realtime extent size, blocks */
	xfs_agblock_t	sb_agblocks;	/* size of an allocation group */
	xfs_agnumber_t	sb_agcount;	/* number of allocation groups */
	xfs_extlen_t	sb_rbmblocks;	/* number of rt bitmap blocks */
	xfs_extlen_t	sb_logblocks;	/* number of log blocks */
	__uint16_t	sb_versionnum;	/* header version == XFS_SB_VERSION */
	__uint16_t	sb_sectsize;	/* volume sector size, bytes */
	__uint16_t	sb_inodesize;	/* inode size, bytes */
	__uint16_t	sb_inopblock;	/* inodes per block */
	char		sb_fname[12];	/* file system name */
	__uint8_t	sb_blocklog;	/* log2 of sb_blocksize */
	__uint8_t	sb_sectlog;	/* log2 of sb_sectsize */
	__uint8_t	sb_inodelog;	/* log2 of sb_inodesize */
	__uint8_t	sb_inopblog;	/* log2 of sb_inopblock */
	__uint8_t	sb_agblklog;	/* log2 of sb_agblocks (rounded up) */
	__uint8_t	sb_rextslog;	/* log2 of sb_rextents */
	__uint8_t	sb_inprogress;	/* mkfs is in progress, don't mount */
	__uint8_t	sb_imax_pct;	/* max % of fs for inode space */
					/* statistics */
	/*
	 * These fields must remain contiguous.  If you really
	 * want to change their layout, make sure you fix the
	 * code in xfs_trans_apply_sb_deltas().
	 */
	__uint64_t	sb_icount;	/* allocated inodes */
	__uint64_t	sb_ifree;	/* free inodes */
	__uint64_t	sb_fdblocks;	/* free data blocks */
	__uint64_t	sb_frextents;	/* free realtime extents */
	/*
	 * End contiguous fields.
	 */
	xfs_ino_t	sb_uquotino;	/* user quota inode */
	xfs_ino_t	sb_gquotino;	/* group quota inode */
	__uint16_t	sb_qflags;	/* quota flags */
	__uint8_t	sb_flags;	/* misc. flags */
	__uint8_t	sb_shared_vn;	/* shared version number */
	xfs_extlen_t	sb_inoalignmt;	/* inode chunk alignment, fsblocks */
	__uint32_t	sb_unit;	/* stripe or raid unit */
	__uint32_t	sb_width;	/* stripe or raid width */
	__uint8_t	sb_dirblklog;	/* log2 of dir block size (fsbs) */
	__uint8_t	sb_logsectlog;	/* log2 of the log sector size */
	__uint16_t	sb_logsectsize;	/* sector size for the log, bytes */
	__uint32_t	sb_logsunit;	/* stripe unit size for the log */
	__uint32_t	sb_features2;	/* additional feature bits */
} xfs_sb_t;

/*
 * Superblock - on disk version.  Must match the in core version below.
 */
typedef struct xfs_dsb {
	__be32		sb_magicnum;	/* magic number == XFS_SB_MAGIC */
	__be32		sb_blocksize;	/* logical block size, bytes */
	__be64		sb_dblocks;	/* number of data blocks */
	__be64		sb_rblocks;	/* number of realtime blocks */
	__be64		sb_rextents;	/* number of realtime extents */
	uuid_t		sb_uuid;	/* file system unique id */
	__be64		sb_logstart;	/* starting block of log if internal */
	__be64		sb_rootino;	/* root inode number */
	__be64		sb_rbmino;	/* bitmap inode for realtime extents */
	__be64		sb_rsumino;	/* summary inode for rt bitmap */
	__be32		sb_rextsize;	/* realtime extent size, blocks */
	__be32		sb_agblocks;	/* size of an allocation group */
	__be32		sb_agcount;	/* number of allocation groups */
	__be32		sb_rbmblocks;	/* number of rt bitmap blocks */
	__be32		sb_logblocks;	/* number of log blocks */
	__be16		sb_versionnum;	/* header version == XFS_SB_VERSION */
	__be16		sb_sectsize;	/* volume sector size, bytes */
	__be16		sb_inodesize;	/* inode size, bytes */
	__be16		sb_inopblock;	/* inodes per block */
	char		sb_fname[12];	/* file system name */
	__u8		sb_blocklog;	/* log2 of sb_blocksize */
	__u8		sb_sectlog;	/* log2 of sb_sectsize */
	__u8		sb_inodelog;	/* log2 of sb_inodesize */
	__u8		sb_inopblog;	/* log2 of sb_inopblock */
	__u8		sb_agblklog;	/* log2 of sb_agblocks (rounded up) */
	__u8		sb_rextslog;	/* log2 of sb_rextents */
	__u8		sb_inprogress;	/* mkfs is in progress, don't mount */
	__u8		sb_imax_pct;	/* max % of fs for inode space */
					/* statistics */
	/*
	 * These fields must remain contiguous.  If you really
	 * want to change their layout, make sure you fix the
	 * code in xfs_trans_apply_sb_deltas().
	 */
	__be64		sb_icount;	/* allocated inodes */
	__be64		sb_ifree;	/* free inodes */
	__be64		sb_fdblocks;	/* free data blocks */
	__be64		sb_frextents;	/* free realtime extents */
	/*
	 * End contiguous fields.
	 */
	__be64		sb_uquotino;	/* user quota inode */
	__be64		sb_gquotino;	/* group quota inode */
	__be16		sb_qflags;	/* quota flags */
	__u8		sb_flags;	/* misc. flags */
	__u8		sb_shared_vn;	/* shared version number */
	__be32		sb_inoalignmt;	/* inode chunk alignment, fsblocks */
	__be32		sb_unit;	/* stripe or raid unit */
	__be32		sb_width;	/* stripe or raid width */
	__u8		sb_dirblklog;	/* log2 of dir block size (fsbs) */
	__u8		sb_logsectlog;	/* log2 of the log sector size */
	__be16		sb_logsectsize;	/* sector size for the log, bytes */
	__be32		sb_logsunit;	/* stripe unit size for the log */
	__be32		sb_features2;	/* additional feature bits */
} xfs_dsb_t;

/*
 * Sequence number values for the fields.
 */
typedef enum {
	XFS_SBS_MAGICNUM, XFS_SBS_BLOCKSIZE, XFS_SBS_DBLOCKS, XFS_SBS_RBLOCKS,
	XFS_SBS_REXTENTS, XFS_SBS_UUID, XFS_SBS_LOGSTART, XFS_SBS_ROOTINO,
	XFS_SBS_RBMINO, XFS_SBS_RSUMINO, XFS_SBS_REXTSIZE, XFS_SBS_AGBLOCKS,
	XFS_SBS_AGCOUNT, XFS_SBS_RBMBLOCKS, XFS_SBS_LOGBLOCKS,
	XFS_SBS_VERSIONNUM, XFS_SBS_SECTSIZE, XFS_SBS_INODESIZE,
	XFS_SBS_INOPBLOCK, XFS_SBS_FNAME, XFS_SBS_BLOCKLOG,
	XFS_SBS_SECTLOG, XFS_SBS_INODELOG, XFS_SBS_INOPBLOG, XFS_SBS_AGBLKLOG,
	XFS_SBS_REXTSLOG, XFS_SBS_INPROGRESS, XFS_SBS_IMAX_PCT, XFS_SBS_ICOUNT,
	XFS_SBS_IFREE, XFS_SBS_FDBLOCKS, XFS_SBS_FREXTENTS, XFS_SBS_UQUOTINO,
	XFS_SBS_GQUOTINO, XFS_SBS_QFLAGS, XFS_SBS_FLAGS, XFS_SBS_SHARED_VN,
	XFS_SBS_INOALIGNMT, XFS_SBS_UNIT, XFS_SBS_WIDTH, XFS_SBS_DIRBLKLOG,
	XFS_SBS_LOGSECTLOG, XFS_SBS_LOGSECTSIZE, XFS_SBS_LOGSUNIT,
	XFS_SBS_FEATURES2,
	XFS_SBS_FIELDCOUNT
} xfs_sb_field_t;

/*
 * Mask values, defined based on the xfs_sb_field_t values.
 * Only define the ones we're using.
 */
#define	XFS_SB_MVAL(x)		(1LL << XFS_SBS_ ## x)
#define	XFS_SB_UUID		XFS_SB_MVAL(UUID)
#define	XFS_SB_FNAME		XFS_SB_MVAL(FNAME)
#define	XFS_SB_ROOTINO		XFS_SB_MVAL(ROOTINO)
#define	XFS_SB_RBMINO		XFS_SB_MVAL(RBMINO)
#define	XFS_SB_RSUMINO		XFS_SB_MVAL(RSUMINO)
#define	XFS_SB_VERSIONNUM	XFS_SB_MVAL(VERSIONNUM)
#define XFS_SB_UQUOTINO		XFS_SB_MVAL(UQUOTINO)
#define XFS_SB_GQUOTINO		XFS_SB_MVAL(GQUOTINO)
#define XFS_SB_QFLAGS		XFS_SB_MVAL(QFLAGS)
#define XFS_SB_SHARED_VN	XFS_SB_MVAL(SHARED_VN)
#define XFS_SB_UNIT		XFS_SB_MVAL(UNIT)
#define XFS_SB_WIDTH		XFS_SB_MVAL(WIDTH)
#define XFS_SB_ICOUNT		XFS_SB_MVAL(ICOUNT)
#define XFS_SB_IFREE		XFS_SB_MVAL(IFREE)
#define XFS_SB_FDBLOCKS		XFS_SB_MVAL(FDBLOCKS)
#define XFS_SB_FEATURES2	XFS_SB_MVAL(FEATURES2)
#define	XFS_SB_NUM_BITS		((int)XFS_SBS_FIELDCOUNT)
#define	XFS_SB_ALL_BITS		((1LL << XFS_SB_NUM_BITS) - 1)
#define	XFS_SB_MOD_BITS		\
	(XFS_SB_UUID | XFS_SB_ROOTINO | XFS_SB_RBMINO | XFS_SB_RSUMINO | \
	 XFS_SB_VERSIONNUM | XFS_SB_UQUOTINO | XFS_SB_GQUOTINO | \
	 XFS_SB_QFLAGS | XFS_SB_SHARED_VN | XFS_SB_UNIT | XFS_SB_WIDTH | \
	 XFS_SB_ICOUNT | XFS_SB_IFREE | XFS_SB_FDBLOCKS | XFS_SB_FEATURES2)


/*
 * Misc. Flags - warning - these will be cleared by xfs_repair unless
 * a feature bit is set when the flag is used.
 */
#define XFS_SBF_NOFLAGS		0x00	/* no flags set */
#define XFS_SBF_READONLY	0x01	/* only read-only mounts allowed */

/*
 * define max. shared version we can interoperate with
 */
#define XFS_SB_MAX_SHARED_VN	0

#define	XFS_SB_VERSION_NUM(sbp)	((sbp)->sb_versionnum & XFS_SB_VERSION_NUMBITS)