dlm: align midcomms message buffer

gcc does not guarantee that an auto buffer is 64bit aligned.
This change allows sparc64 to work.

Signed-off-by: Fabio M. Di Nitto <fabbione@ubuntu.com>
Signed-off-by: David Teigland <teigland@redhat.com>

1 files changed, 9 insertions, 6 deletions

diff --git a/fs/dlm/midcomms.c b/fs/dlm/midcomms.c
index f8c69dda16a0..e69926e984db 100644
--- a/fs/dlm/midcomms.c
+++ b/fs/dlm/midcomms.c
@@ -2,7 +2,7 @@
 *******************************************************************************
 **
 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
-**  Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -58,8 +58,12 @@ static void copy_from_cb(void *dst, const void *base, unsigned offset,
 int dlm_process_incoming_buffer(int nodeid, const void *base,
                                 unsigned offset, unsigned len, unsigned limit)
 {
-        unsigned char __tmp[DLM_INBUF_LEN];
-        struct dlm_header *msg = (struct dlm_header *) __tmp;
+        union {
+                unsigned char __buf[DLM_INBUF_LEN];
+                /* this is to force proper alignment on some arches */
+                struct dlm_header dlm;
+        } __tmp;
+        struct dlm_header *msg = &__tmp.dlm;
         int ret = 0;
         int err = 0;
         uint16_t msglen;
@@ -100,8 +104,7 @@ int dlm_process_incoming_buffer(int nodeid, const void *base,
                    in the buffer on the stack (which should work for most
                    ordinary messages). */
 
-                if (msglen > sizeof(__tmp) &&
-                    msg == (struct dlm_header *) __tmp) {
+                if (msglen > DLM_INBUF_LEN && msg == &__tmp.dlm) {
                         msg = kmalloc(dlm_config.ci_buffer_size, GFP_KERNEL);
                         if (msg == NULL)
                                 return ret;
@@ -119,7 +122,7 @@ int dlm_process_incoming_buffer(int nodeid, const void *base,
                 dlm_receive_buffer(msg, nodeid);
         }
 
-        if (msg != (struct dlm_header *) __tmp)
+        if (msg != &__tmp.dlm)
                 kfree(msg);
 
         return err ? err : ret;