From 13e6d5cdde0e785aa943810f08b801cadd0935df Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 31 Aug 2009 21:00:31 -0300 Subject: 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 978b7237123d007b9fa983af6e0e2fa8f97f9934 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 Reviewed-by: Felix Blyakher Signed-off-by: Felix Blyakher --- fs/xfs/linux-2.6/xfs_file.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) (limited to 'fs/xfs/linux-2.6/xfs_file.c') diff --git a/fs/xfs/linux-2.6/xfs_file.c b/fs/xfs/linux-2.6/xfs_file.c index 0542fd50764..988d8f87bc0 100644 --- a/fs/xfs/linux-2.6/xfs_file.c +++ b/fs/xfs/linux-2.6/xfs_file.c @@ -172,12 +172,21 @@ xfs_file_release( */ STATIC int xfs_file_fsync( - struct file *filp, - struct dentry *dentry, - int datasync) + struct file *file, + struct dentry *dentry, + int datasync) { - xfs_iflags_clear(XFS_I(dentry->d_inode), XFS_ITRUNCATED); - return -xfs_fsync(XFS_I(dentry->d_inode)); + struct inode *inode = dentry->d_inode; + struct xfs_inode *ip = XFS_I(inode); + int error; + + /* capture size updates in I/O completion before writing the inode. */ + error = filemap_fdatawait(inode->i_mapping); + if (error) + return error; + + xfs_iflags_clear(ip, XFS_ITRUNCATED); + return -xfs_fsync(ip); } STATIC int -- cgit v1.2.3-70-g09d2