[PATCH v2 5/5] xfs: only writeback and truncate pages for the freed range

Brian Foster
2014-09-10T13:20:37Z

xfs_free_file_space() only affects the range of the file for which space
is being freed. It currently writes and truncates the page cache from
the start offset of the free to EOF.

Modify xfs_free_file_space() to write back and truncate page cache of
just the range being freed.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/xfs_bmap_util.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index eae763f..809ae7d 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1205,6 +1205,7 @@ xfs_free_file_space(
xfs_bmap_free_t free_list;
xfs_bmbt_irec_t imap;
xfs_off_t ioffset;
+ xfs_off_t iendoffset;
xfs_extlen_t mod=0;
xfs_mount_t *mp;
int nimap;
@@ -1233,12 +1234,13 @@ xfs_free_file_space(
inode_dio_wait(VFS_I(ip));

rounding = max_t(xfs_off_t, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE);
- ioffset = offset & ~(rounding - 1);
- error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
- ioffset, -1);
+ ioffset = round_down(offset, rounding);
+ iendoffset = round_up(offset + len, rounding) - 1;
+ error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping, ioffset,
+ iendoffset);
if (error)
goto out;
- truncate_pagecache_range(VFS_I(ip), ioffset, -1);
+ truncate_pagecache_range(VFS_I(ip), ioffset, iendoffset);

/*
* Need to zero the stuff we're not freeing, on disk.
--
1.8.3.1