From 4918ef4ea008cd2ff47eb852894e3f9b9047f4f3 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Tue, 30 Oct 2018 10:46:33 +1100 Subject: [PATCH] xfs: fix pagecache truncation prior to reflink Prior to remapping blocks, it is necessary to remove pages from the destination file's page cache. Unfortunately, the truncation is not aggressive enough -- if page size > block size, we'll end up zeroing subpage blocks instead of removing them. So, round the start offset down and the end offset up to page boundaries. We already wrote all the dirty data so the larger range shouldn't be a problem. Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner Reviewed-by: Christoph Hellwig Signed-off-by: Dave Chinner --- fs/xfs/xfs_reflink.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index 9b1ea42c81d1..e8e86646bb4b 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -1369,8 +1369,9 @@ xfs_reflink_remap_prep( goto out_unlock; /* Zap any page cache for the destination file's range. */ - truncate_inode_pages_range(&inode_out->i_data, pos_out, - PAGE_ALIGN(pos_out + *len) - 1); + truncate_inode_pages_range(&inode_out->i_data, + round_down(pos_out, PAGE_SIZE), + round_up(pos_out + *len, PAGE_SIZE) - 1); return 1; out_unlock: