| Message ID | 20181008101624.28120-1-hch@lst.de (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | xfs: cancel COW blocks before swapext | expand |
On Mon, Oct 08, 2018 at 12:16:24PM +0200, Christoph Hellwig wrote: > We need to make sure we have no outstanding COW blocks before we swap > extents, as there is nothing preventing us from having preallocated COW > delalloc on either inode that swapext is called on. That case can > easily be reproduced by running generic/324 in always_cow mode: > Ok, I'm a little curious how you end up with delayed allocation cowblocks in the temporary inode (created by xfs_fsr), but it sounds like you have a mechanism enabled that utilizes cow in more situations than purely shared blocks..? Out of curiosity, what does xfs_fsr do to trigger cow fork reservation in always_cow mode? Is it limited to overwrites, or do all writes result in some kind of cow reservation? > [ 620.760572] XFS: Assertion failed: tip->i_delayed_blks == 0, file: fs/xfs/xfs_bmap_util.c, line: 1669 > [ 620.761608] ------------[ cut here ]------------ ... > > Signed-off-by: Christoph Hellwig <hch@lst.de> > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> > --- > fs/xfs/xfs_bmap_util.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c > index 7cfda25f1bb1..97f7543fdfb6 100644 > --- a/fs/xfs/xfs_bmap_util.c > +++ b/fs/xfs/xfs_bmap_util.c > @@ -1465,6 +1465,12 @@ xfs_swap_extent_flush( > return error; > truncate_pagecache_range(VFS_I(ip), 0, -1); > > + if (xfs_inode_has_cow_data(ip)) { > + error = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true); > + if (error) > + return error; > + } > + Same comment as before.. we have 20-30 lines of code in xfs_swap_extents() dedicated to swapping the cowblocks tags and cow forks when ->if_bytes != 0. This patch appears to nullify that code, so we should at least be able to reduce some of that to asserts. Brian > /* Verify O_DIRECT for ftmp */ > if (VFS_I(ip)->i_mapping->nrpages) > return -EINVAL; > -- > 2.19.0 >
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 7cfda25f1bb1..97f7543fdfb6 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -1465,6 +1465,12 @@ xfs_swap_extent_flush( return error; truncate_pagecache_range(VFS_I(ip), 0, -1); + if (xfs_inode_has_cow_data(ip)) { + error = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true); + if (error) + return error; + } + /* Verify O_DIRECT for ftmp */ if (VFS_I(ip)->i_mapping->nrpages) return -EINVAL;