Btrfs: unplug all devices in the unplug call back

For larger multi-device filesystems, there was logic to limit the
number of devices unplugged to just the page that was sent to our sync_page
function.

But, the code wasn't always unplugging the right device.  Since this was
just an optimization, disable it for now.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index e18250a6fd2db6009d07eadd339fcc3e3e09fc15..0e8d31274c92733af7ea1de54fb61bdcb0bf888c 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1214,7 +1214,7 @@ void btrfs_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
        u64 offset;
 
        /* the generic O_DIRECT read code does this */
-       if (!page) {
+       if (1 || !page) {
                __unplug_io_fn(bdi, page);
                return;
        }