linux/fs/xfs/xfs_ialloc_btree.h
Christoph Hellwig 7cc95a821d [XFS] Always use struct xfs_btree_block instead of short / longform
structures.

Always use the generic xfs_btree_block type instead of the short / long
structures. Add XFS_BTREE_SBLOCK_LEN / XFS_BTREE_LBLOCK_LEN defines for
the length of a short / long form block. The rationale for this is that we
will grow more btree block header variants to support CRCs and other RAS
information, and always accessing them through the same datatype with
unions for the short / long form pointers makes implementing this much
easier.

SGI-PV: 988146

SGI-Modid: xfs-linux-melb:xfs-kern:32300a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-10-30 17:14:34 +11:00

127 lines
3.7 KiB
C

/*
* 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_IALLOC_BTREE_H__
#define __XFS_IALLOC_BTREE_H__
/*
* Inode map on-disk structures
*/
struct xfs_buf;
struct xfs_btree_cur;
struct xfs_mount;
/*
* There is a btree for the inode map per allocation group.
*/
#define XFS_IBT_MAGIC 0x49414254 /* 'IABT' */
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_MASKN(i,n) xfs_inobt_maskn(i,n)
static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
{
return (((n) >= XFS_INODES_PER_CHUNK ? \
(xfs_inofree_t)0 : ((xfs_inofree_t)1 << (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;
/*
* Bit manipulations for ir_free.
*/
#define XFS_INOBT_MASK(i) ((xfs_inofree_t)1 << (i))
#define XFS_INOBT_IS_FREE(rp,i) \
(((rp)->ir_free & XFS_INOBT_MASK(i)) != 0)
#define XFS_INOBT_SET_FREE(rp,i) ((rp)->ir_free |= XFS_INOBT_MASK(i))
#define XFS_INOBT_CLR_FREE(rp,i) ((rp)->ir_free &= ~XFS_INOBT_MASK(i))
/*
* Maximum number of inode btree levels.
*/
#define XFS_IN_MAXLEVELS(mp) ((mp)->m_in_maxlevels)
/*
* 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))
/*
* Btree block header size depends on a superblock flag.
*
* (not quite yet, but soon)
*/
#define XFS_INOBT_BLOCK_LEN(mp) XFS_BTREE_SBLOCK_LEN
/*
* Record, key, and pointer address macros for btree blocks.
*
* (note that some of these may appear unused, but they are used in userspace)
*/
#define XFS_INOBT_REC_ADDR(mp, block, index) \
((xfs_inobt_rec_t *) \
((char *)(block) + \
XFS_INOBT_BLOCK_LEN(mp) + \
(((index) - 1) * sizeof(xfs_inobt_rec_t))))
#define XFS_INOBT_KEY_ADDR(mp, block, index) \
((xfs_inobt_key_t *) \
((char *)(block) + \
XFS_INOBT_BLOCK_LEN(mp) + \
((index) - 1) * sizeof(xfs_inobt_key_t)))
#define XFS_INOBT_PTR_ADDR(mp, block, index, maxrecs) \
((xfs_inobt_ptr_t *) \
((char *)(block) + \
XFS_INOBT_BLOCK_LEN(mp) + \
(maxrecs) * sizeof(xfs_inobt_key_t) + \
((index) - 1) * sizeof(xfs_inobt_ptr_t)))
extern struct xfs_btree_cur *xfs_inobt_init_cursor(struct xfs_mount *,
struct xfs_trans *, struct xfs_buf *, xfs_agnumber_t);
extern int xfs_inobt_maxrecs(struct xfs_mount *, int, int);
#endif /* __XFS_IALLOC_BTREE_H__ */