From 78f0cc9d55cbe75faccc0135371c45912a34e6ed Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 18 Feb 2019 09:38:46 -0800 Subject: xfs: don't use delalloc extents for COW on files with extsize hints While using delalloc for extsize hints is generally a good idea, the current code that does so only for COW doesn't help us much and creates a lot of special cases. Switch it to use real allocations like we do for direct I/O. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_iomap.c | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-) (limited to 'fs/xfs/xfs_iomap.c') diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index df6eda336f17..be9d2a4b190a 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -918,22 +918,29 @@ xfs_file_iomap_begin( * been done up front, so we don't need to do them here. */ if (xfs_is_reflink_inode(ip)) { + struct xfs_bmbt_irec orig = imap; + /* if zeroing doesn't need COW allocation, then we are done. */ if ((flags & IOMAP_ZERO) && !needs_cow_for_zeroing(&imap, nimaps)) goto out_found; - if (flags & IOMAP_DIRECT) { - /* may drop and re-acquire the ilock */ - error = xfs_reflink_allocate_cow(ip, &imap, &shared, - &lockmode); - if (error) - goto out_unlock; - } else { - error = xfs_reflink_reserve_cow(ip, &imap); - if (error) - goto out_unlock; - } + /* may drop and re-acquire the ilock */ + error = xfs_reflink_allocate_cow(ip, &imap, &shared, &lockmode, + flags); + if (error) + goto out_unlock; + + /* + * For buffered writes we need to report the address of the + * previous block (if there was any) so that the higher level + * write code can perform read-modify-write operations. For + * direct I/O code, which must be block aligned we need to + * report the newly allocated address. + */ + if (!(flags & IOMAP_DIRECT) && + orig.br_startblock != HOLESTARTBLOCK) + imap = orig; end_fsb = imap.br_startoff + imap.br_blockcount; length = XFS_FSB_TO_B(mp, end_fsb) - offset; -- cgit v1.2.3