From 5c989a0ee06eb77a44baffd1779a5dbb9a7e873f Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <darrick.wong@oracle.com>
Date: Sun, 10 Dec 2017 18:03:54 -0800
Subject: [PATCH] xfs: remove dest file's post-eof preallocations before
reflinking
Git-commit: 5c989a0ee06eb77a44baffd1779a5dbb9a7e873f
Patch-mainline: v4.15-rc5
References: bsc#1132365, bsc#1132219
If we try to reflink into a file with post-eof preallocations at an
offset well past the preallocations, we increase i_size as one would
expect. However, those allocations do not have page cache backing them,
so they won't get cleaned out on their own. This leads to asserts in
the collapse/insert range code and xfs_destroy_inode when they encounter
delalloc extents they weren't expecting to find.
Since there are plenty of other places where we dump those post-eof
blocks, do the same to the reflink destination file before we start
remapping extents. This was found by adding clonerange support to
fsstress and running it in write-only mode.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Anthony Iliopoulos <ailiopoulos@suse.com>
---
fs/xfs/xfs_reflink.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index cf7c8f81bebb..e13f5ad57a03 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -1291,6 +1291,17 @@ xfs_reflink_remap_range(
trace_xfs_reflink_remap_range(src, pos_in, len, dest, pos_out);
+ /*
+ * Clear out post-eof preallocations because we don't have page cache
+ * backing the delayed allocations and they'll never get freed on
+ * their own.
+ */
+ if (xfs_can_free_eofblocks(dest, true)) {
+ ret = xfs_free_eofblocks(dest);
+ if (ret)
+ goto out_unlock;
+ }
+
/* Set flags and remap blocks. */
ret = xfs_reflink_set_inode_flag(src, dest);
if (ret)
--
2.16.4