linux_dsm_epyc7002/fs/xfs/libxfs/xfs_ialloc_btree.h
Brian Foster 4148c347a4 xfs: helper to convert holemask to inode alloc. bitmap
The inobt record holemask field is a condensed data type designed to fit
into the existing on-disk record and is zero based (allocated regions
are set to 0, sparse regions are set to 1) to provide backwards
compatibility. This makes the type somewhat complex for use in higher
level inode manipulations such as individual inode allocation, etc.

Rather than foist the complexity of dealing with this field to every bit
of logic that requires inode granular information, create a helper to
convert the holemask to an inode allocation bitmap. The inode allocation
bitmap is inode granularity similar to the inobt record free mask and
indicates which inodes of the chunk are physically allocated on disk,
irrespective of whether the inode is considered allocated or free by the
filesystem.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-05-29 09:09:05 +10:00

69 lines
2.1 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;
/*
* Btree block header size depends on a superblock flag.
*/
#define XFS_INOBT_BLOCK_LEN(mp) \
(xfs_sb_version_hascrc(&((mp)->m_sb)) ? \
XFS_BTREE_SBLOCK_CRC_LEN : 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,
xfs_btnum_t);
extern int xfs_inobt_maxrecs(struct xfs_mount *, int, int);
/* ir_holemask to inode allocation bitmap conversion */
uint64_t xfs_inobt_irec_to_allocmask(struct xfs_inobt_rec_incore *);
#endif /* __XFS_IALLOC_BTREE_H__ */