drm: radeon: Fix unaligned access in r300_scratch().

In compat mode, the cmdbuf->buf 64-bit address cookie can
potentially be only 32-bit aligned.  Dereferencing this as
64-bit causes expensive unaligned traps on platforms like
sparc64.

Use get_unaligned() to fix.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
David Miller 2009-02-18 01:35:23 -08:00 committed by Dave Airlie
parent f1a2a9b618
commit 958a6f8ccb

View File

@ -37,6 +37,8 @@
#include "radeon_drv.h"
#include "r300_reg.h"
#include <asm/unaligned.h>
#define R300_SIMULTANEOUS_CLIPRECTS 4
/* Values for R300_RE_CLIPRECT_CNTL depending on the number of cliprects
@ -917,6 +919,7 @@ static int r300_scratch(drm_radeon_private_t *dev_priv,
{
u32 *ref_age_base;
u32 i, buf_idx, h_pending;
u64 ptr_addr;
RING_LOCALS;
if (cmdbuf->bufsz <
@ -930,7 +933,8 @@ static int r300_scratch(drm_radeon_private_t *dev_priv,
dev_priv->scratch_ages[header.scratch.reg]++;
ref_age_base = (u32 *)(unsigned long)*((uint64_t *)cmdbuf->buf);
ptr_addr = get_unaligned((u64 *)cmdbuf->buf);
ref_age_base = (u32 *)(unsigned long)ptr_addr;
cmdbuf->buf += sizeof(u64);
cmdbuf->bufsz -= sizeof(u64);