xfs: remove buftarg hash for external devices

For RT and external log devices, we never use hashed buffers on them
now.  Remove the buftarg hash tables that are set up for them.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>

diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index 975d6589394af4c939c37c01558dfc646b61a162..251bcdc6352ed1216c7f95bf9ef4256afd676607 100644 (file)
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -1458,7 +1458,11 @@ xfs_alloc_bufhash(
 {
        unsigned int            i;
 
-       btp->bt_hashshift = external ? 3 : 12;  /* 8 or 4096 buckets */
+       if (external) {
+               btp->bt_hash = NULL;
+               return;
+       }
+       btp->bt_hashshift = 12; /* 4096 buckets */
        btp->bt_hash = kmem_zalloc_large((1 << btp->bt_hashshift) *
                                         sizeof(xfs_bufhash_t));
        for (i = 0; i < (1 << btp->bt_hashshift); i++) {