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/*
 * Taken from Linux kernel tree (linux/fs/xfs)
 *
 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * Copyright (c) 2012 Paulo Alcantara <pcacjr@zytor.com>
 *
 * 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_

#include <stddef.h>

#include <sys/types.h>

typedef unsigned char uuid_t[16];

/*
 * 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		"XFSB"		/* '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_BORGBIT		0x4000	/* ASCII only case-insens. */
#define	XFS_SB_VERSION_MOREBITSBIT	0x8000
#define	XFS_SB_VERSION_OKSASHFBITS	\
	(XFS_SB_VERSION_EXTFLGBIT | \
	 XFS_SB_VERSION_DIRV2BIT | \
	 XFS_SB_VERSION_BORGBIT)
#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_PARENTBIT	0x00000010	/* parent pointers */
#define XFS_SB_VERSION2_PROJID32BIT	0x00000080	/* 32 bit project id */

#define	XFS_SB_VERSION2_OKREALFBITS	\
	(XFS_SB_VERSION2_LAZYSBCOUNTBIT	| \
	 XFS_SB_VERSION2_ATTR2BIT	| \
	 XFS_SB_VERSION2_PROJID32BIT)
#define	XFS_SB_VERSION2_OKSASHFBITS	\
	(0)
#define XFS_SB_VERSION2_OKREALBITS	\
	(XFS_SB_VERSION2_OKREALFBITS |	\
	 XFS_SB_VERSION2_OKSASHFBITS )

/*
 * 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_BAD_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_BAD_FEATURES2	XFS_SB_MVAL(BAD_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 | \
	 XFS_SB_BAD_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)

/*
 * end of superblock version macros
 */

#define	XFS_SB_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_SB_DADDR)
#define XFS_BUF_TO_SBP(bp)	((xfs_dsb_t *)((bp)->b_addr))

#define	XFS_HDR_BLOCK(mp,d)	((xfs_agblock_t)XFS_BB_TO_FSBT(mp,d))
#define	XFS_DADDR_TO_FSB(mp,d)	XFS_AGB_TO_FSB(mp, \
			xfs_daddr_to_agno(mp,d), xfs_daddr_to_agbno(mp,d))
#define	XFS_FSB_TO_DADDR(mp,fsbno)	XFS_AGB_TO_DADDR(mp, \
			XFS_FSB_TO_AGNO(mp,fsbno), XFS_FSB_TO_AGBNO(mp,fsbno))

/*
 * File system sector to basic block conversions.
 */
#define XFS_FSS_TO_BB(mp,sec)	((sec) << (mp)->m_sectbb_log)

/*
 * File system block to basic block conversions.
 */
#define	XFS_FSB_TO_BB(mp,fsbno)	((fsbno) << (mp)->m_blkbb_log)
#define	XFS_BB_TO_FSB(mp,bb)	\
	(((bb) + (XFS_FSB_TO_BB(mp,1) - 1)) >> (mp)->m_blkbb_log)
#define	XFS_BB_TO_FSBT(mp,bb)	((bb) >> (mp)->m_blkbb_log)

/*
 * File system block to byte conversions.
 */
#define XFS_FSB_TO_B(mp,fsbno)	((xfs_fsize_t)(fsbno) << (mp)->m_sb.sb_blocklog)
#define XFS_B_TO_FSB(mp,b)	\
	((((uint64_t)(b)) + (mp)->m_blockmask) >> (mp)->m_sb.sb_blocklog)
#define XFS_B_TO_FSBT(mp,b)	(((uint64_t)(b)) >> (mp)->m_sb.sb_blocklog)
#define XFS_B_FSB_OFFSET(mp,b)	((b) & (mp)->m_blockmask)

#endif	/* XFS_SB_H_ */