linux/fs/xfs/xfs_ialloc.h
Dave Chinner 1813dd6405 xfs: convert buffer verifiers to an ops structure.
To separate the verifiers from iodone functions and associate read
and write verifiers at the same time, introduce a buffer verifier
operations structure to the xfs_buf.

This avoids the need for assigning the write verifier, clearing the
iodone function and re-running ioend processing in the read
verifier, and gets rid of the nasty "b_pre_io" name for the write
verifier function pointer. If we ever need to, it will also be
easier to add further content specific callbacks to a buffer with an
ops structure in place.

We also avoid needing to export verifier functions, instead we
can simply export the ops structures for those that are needed
outside the function they are defined in.

This patch also fixes a directory block readahead verifier issue
it exposed.

This patch also adds ops callbacks to the inode/alloc btree blocks
initialised by growfs. These will need more work before they will
work with CRCs.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Phil White <pwhite@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-15 21:35:12 -06:00

156 lines
5.0 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_imap;
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
/*
* Move inodes in clusters of this size.
*/
#define XFS_INODE_BIG_CLUSTER_SIZE 8192
#define XFS_INODE_CLUSTER_SIZE(mp) (mp)->m_inode_cluster_size
/*
* Make an inode pointer out of the buffer/offset.
*/
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));
}
/*
* 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) */
umode_t mode, /* mode bits for new inode */
int okalloc, /* ok to allocate more space */
struct xfs_buf **agbp, /* buf for a.g. inode header */
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 imap, for mapping it into a buffer.
*/
int
xfs_imap(
struct xfs_mount *mp, /* file system mount structure */
struct xfs_trans *tp, /* transaction pointer */
xfs_ino_t ino, /* inode to locate */
struct xfs_imap *imap, /* location map structure */
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 */
/*
* Read in the allocation group header to initialise the per-ag data
* in the mount structure
*/
int
xfs_ialloc_pagi_init(
struct xfs_mount *mp, /* file system mount structure */
struct xfs_trans *tp, /* transaction pointer */
xfs_agnumber_t agno); /* allocation group number */
/*
* Lookup a record by ino in the btree given by cur.
*/
int xfs_inobt_lookup(struct xfs_btree_cur *cur, xfs_agino_t ino,
xfs_lookup_t dir, int *stat);
/*
* Get the data from the pointed-to record.
*/
int xfs_inobt_get_rec(struct xfs_btree_cur *cur,
xfs_inobt_rec_incore_t *rec, int *stat);
extern const struct xfs_buf_ops xfs_agi_buf_ops;
#endif /* __XFS_IALLOC_H__ */