ext4: fix an ext3 collapse range regression in xfstests

The xfstests test suite assumes that an attempt to collapse range on
the range (0, 1) will return EOPNOTSUPP if the file system does not
support collapse range.  Commit 280227a75b56: "ext4: move check under
lock scope to close a race" broke this, and this caused xfstests to
fail when run when testing file systems that did not have the extents
feature enabled.

Reported-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 451b92a9958abb859ed5bf2d12f4b4327cbfdaac..e003a1e81dc351c76465908bec21702ecc6d4b91 100644 (file)
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -5396,6 +5396,14 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len)
        loff_t new_size, ioffset;
        int ret;
 
+       /*
+        * We need to test this early because xfstests assumes that a
+        * collapse range of (0, 1) will return EOPNOTSUPP if the file
+        * system does not support collapse range.
+        */
+       if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
+               return -EOPNOTSUPP;
+
        /* Collapse range works only on fs block size aligned offsets. */
        if (offset & (EXT4_CLUSTER_SIZE(sb) - 1) ||
            len & (EXT4_CLUSTER_SIZE(sb) - 1))