From: Darrick J. Wong Date: Mon, 29 Oct 2018 23:43:16 +0000 (+1100) Subject: ocfs2: fix pagecache truncation prior to reflink X-Git-Tag: v4.20-rc1~23^2~8 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=a8a94302c9754d05069ee149cf01df8aa5116aaa;p=users%2Fdwmw2%2Flinux.git ocfs2: 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 should be fine. Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner Signed-off-by: Dave Chinner --- diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c index 2a5c96bc96774..7c709229e1084 100644 --- a/fs/ocfs2/refcounttree.c +++ b/fs/ocfs2/refcounttree.c @@ -4862,8 +4862,9 @@ int ocfs2_reflink_remap_range(struct file *file_in, SINGLE_DEPTH_NESTING); /* 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); ret = ocfs2_reflink_remap_blocks(inode_in, in_bh, pos_in, inode_out, out_bh, pos_out, len);