Btrfs: fix compressed write corruption on enospc

commit ce62003f690dff38d3164a632ec69efa15c32cbf upstream.

When failing to allocate space for the whole compressed extent, we'll
fallback to uncompressed IO, but we've forgotten to redirty the pages
which belong to this compressed extent, and these 'clean' pages will
simply skip 'submit' part and go to endio directly, at last we got data
corruption as we write nothing.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Tested-By: Martin Steigerwald <martin@lichtvoll.de>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 3668048e16f8fa835c3ffff9ed85998ee201ec58..8ea7610fbaf3eb182321951f96f3fc1c2b498a68 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -709,6 +709,18 @@ retry:
                                unlock_extent(io_tree, async_extent->start,
                                              async_extent->start +
                                              async_extent->ram_size - 1);
+
+                               /*
+                                * we need to redirty the pages if we decide to
+                                * fallback to uncompressed IO, otherwise we
+                                * will not submit these pages down to lower
+                                * layers.
+                                */
+                               extent_range_redirty_for_io(inode,
+                                               async_extent->start,
+                                               async_extent->start +
+                                               async_extent->ram_size - 1);
+
                                goto retry;
                        }
                        goto out_free;