freebsd-dev/sys/gnu/fs/xfs/xfs_ialloc.h
Craig Rodrigues 331b6cc0ea Sync XFS for FreeBSD tree with newer changes from SGI XFS for Linux tree.
Improve support for writing to XFS partitions.

Work done by:	Russell Cattelan <cattelan at xfs dot org>
2006-06-09 06:04:06 +00:00

155 lines
5.1 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_H__
#define __XFS_IALLOC_H__
struct xfs_buf;
struct xfs_dinode;
struct xfs_mount;
struct xfs_trans;
/*
* Allocation parameters for inode allocation.
*/
#define XFS_IALLOC_INODES(mp) (mp)->m_ialloc_inos
#define XFS_IALLOC_BLOCKS(mp) (mp)->m_ialloc_blks
/*
* For small block file systems, move inodes in clusters of this size.
* When we don't have a lot of memory, however, we go a bit smaller
* to reduce the number of AGI and ialloc btree blocks we need to keep
* around for xfs_dilocate(). We choose which one to use in
* xfs_mount_int().
*/
#define XFS_INODE_BIG_CLUSTER_SIZE 8192
#define XFS_INODE_SMALL_CLUSTER_SIZE 4096
#define XFS_INODE_CLUSTER_SIZE(mp) (mp)->m_inode_cluster_size
/*
* Make an inode pointer out of the buffer/offset.
*/
#define XFS_MAKE_IPTR(mp,b,o) xfs_make_iptr(mp,b,o)
static inline struct xfs_dinode *
xfs_make_iptr(struct xfs_mount *mp, struct xfs_buf *b, int o)
{
return (xfs_dinode_t *)
(xfs_buf_offset(b, o << (mp)->m_sb.sb_inodelog));
}
/*
* Find a free (set) bit in the inode bitmask.
*/
#define XFS_IALLOC_FIND_FREE(fp) xfs_ialloc_find_free(fp)
static inline int xfs_ialloc_find_free(xfs_inofree_t *fp)
{
return xfs_lowbit64(*fp);
}
#ifdef __KERNEL__
/*
* Allocate an inode on disk.
* Mode is used to tell whether the new inode will need space, and whether
* it is a directory.
*
* To work within the constraint of one allocation per transaction,
* xfs_dialloc() is designed to be called twice if it has to do an
* allocation to make more free inodes. If an inode is
* available without an allocation, agbp would be set to the current
* agbp and alloc_done set to false.
* If an allocation needed to be done, agbp would be set to the
* inode header of the allocation group and alloc_done set to true.
* The caller should then commit the current transaction and allocate a new
* transaction. xfs_dialloc() should then be called again with
* the agbp value returned from the previous call.
*
* Once we successfully pick an inode its number is returned and the
* on-disk data structures are updated. The inode itself is not read
* in, since doing so would break ordering constraints with xfs_reclaim.
*
* *agbp should be set to NULL on the first call, *alloc_done set to FALSE.
*/
int /* error */
xfs_dialloc(
struct xfs_trans *tp, /* transaction pointer */
xfs_ino_t parent, /* parent inode (directory) */
mode_t mode, /* mode bits for new inode */
int okalloc, /* ok to allocate more space */
struct xfs_buf **agbp, /* buf for a.g. inode header */
boolean_t *alloc_done, /* an allocation was done to replenish
the free inodes */
xfs_ino_t *inop); /* inode number allocated */
/*
* Free disk inode. Carefully avoids touching the incore inode, all
* manipulations incore are the caller's responsibility.
* The on-disk inode is not changed by this operation, only the
* btree (free inode mask) is changed.
*/
int /* error */
xfs_difree(
struct xfs_trans *tp, /* transaction pointer */
xfs_ino_t inode, /* inode to be freed */
struct xfs_bmap_free *flist, /* extents to free */
int *delete, /* set if inode cluster was deleted */
xfs_ino_t *first_ino); /* first inode in deleted cluster */
/*
* Return the location of the inode in bno/len/off,
* for mapping it into a buffer.
*/
int
xfs_dilocate(
struct xfs_mount *mp, /* file system mount structure */
struct xfs_trans *tp, /* transaction pointer */
xfs_ino_t ino, /* inode to locate */
xfs_fsblock_t *bno, /* output: block containing inode */
int *len, /* output: num blocks in cluster*/
int *off, /* output: index in block of inode */
uint flags); /* flags for inode btree lookup */
/*
* Compute and fill in value of m_in_maxlevels.
*/
void
xfs_ialloc_compute_maxlevels(
struct xfs_mount *mp); /* file system mount structure */
/*
* Log specified fields for the ag hdr (inode section)
*/
void
xfs_ialloc_log_agi(
struct xfs_trans *tp, /* transaction pointer */
struct xfs_buf *bp, /* allocation group header buffer */
int fields); /* bitmask of fields to log */
/*
* Read in the allocation group header (inode allocation section)
*/
int /* error */
xfs_ialloc_read_agi(
struct xfs_mount *mp, /* file system mount structure */
struct xfs_trans *tp, /* transaction pointer */
xfs_agnumber_t agno, /* allocation group number */
struct xfs_buf **bpp); /* allocation group hdr buf */
#endif /* __KERNEL__ */
#endif /* __XFS_IALLOC_H__ */