alistair23-linux/fs/xfs/xfs_rw.h
Christoph Hellwig 13e6d5cdde xfs: merge fsync and O_SYNC handling
The guarantees for O_SYNC are exactly the same as the ones we need to
make for an fsync call (and given that Linux O_SYNC is O_DSYNC the
equivalent is fdadatasync, but we treat both the same in XFS), except
with a range data writeout.  Jan Kara has started unifying these two
path for filesystems using the generic helpers, and I've started to
look at XFS.

The actual transaction commited by xfs_fsync and xfs_write_sync_logforce
has a different transaction number, but actually is exactly the same.
We'll only use the fsync transaction going forward.  One major difference
is that xfs_write_sync_logforce never issues a cache flush unless we
commit a transaction causing that as a side-effect, which is an obvious
bug in the O_SYNC handling.  Second all the locking and i_update_size
vs i_update_core changes from 978b723712
never made it to xfs_write_sync_logforce, so we add them back.

To make xfs_fsync easily usable from the O_SYNC path, the filemap_fdatawait
call is moved up to xfs_file_fsync, so that we don't wait on the whole
file after we already waited for our portion in xfs_write.

We'll also use a plain call to filemap_write_and_wait_range instead
of the previous sync_page_rang which did it in two steps including
an half-hearted inode write out that doesn't help us.

Once we're done with this also remove the now useless i_update_size
tracking.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-09-01 12:45:57 -05:00

81 lines
2.3 KiB
C

/*
* Copyright (c) 2000-2006 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_RW_H__
#define __XFS_RW_H__
struct xfs_buf;
struct xfs_inode;
struct xfs_mount;
/*
* Convert the given file system block to a disk block.
* We have to treat it differently based on whether the
* file is a real time file or not, because the bmap code
* does.
*/
static inline xfs_daddr_t
xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb)
{
return (XFS_IS_REALTIME_INODE(ip) ? \
(xfs_daddr_t)XFS_FSB_TO_BB((ip)->i_mount, (fsb)) : \
XFS_FSB_TO_DADDR((ip)->i_mount, (fsb)));
}
/*
* Flags for xfs_free_eofblocks
*/
#define XFS_FREE_EOF_LOCK (1<<0)
#define XFS_FREE_EOF_NOLOCK (1<<1)
/*
* helper function to extract extent size hint from inode
*/
STATIC_INLINE xfs_extlen_t
xfs_get_extsz_hint(
xfs_inode_t *ip)
{
xfs_extlen_t extsz;
if (unlikely(XFS_IS_REALTIME_INODE(ip))) {
extsz = (ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE)
? ip->i_d.di_extsize
: ip->i_mount->m_sb.sb_rextsize;
ASSERT(extsz);
} else {
extsz = (ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE)
? ip->i_d.di_extsize : 0;
}
return extsz;
}
/*
* Prototypes for functions in xfs_rw.c.
*/
extern int xfs_write_clear_setuid(struct xfs_inode *ip);
extern int xfs_bwrite(struct xfs_mount *mp, struct xfs_buf *bp);
extern int xfs_bioerror(struct xfs_buf *bp);
extern int xfs_bioerror_relse(struct xfs_buf *bp);
extern int xfs_read_buf(struct xfs_mount *mp, xfs_buftarg_t *btp,
xfs_daddr_t blkno, int len, uint flags,
struct xfs_buf **bpp);
extern void xfs_ioerror_alert(char *func, struct xfs_mount *mp,
xfs_buf_t *bp, xfs_daddr_t blkno);
#endif /* __XFS_RW_H__ */