[PATCH] optional ZONE_DMA: optional ZONE_DMA for ia64

ZONE_DMA less operation for IA64 SGI platform

Disable ZONE_DMA for SGI SN2.  All memory is addressable by all devices and we
do not need any special memory pool.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/arch/ia64/mm/contig.c b/arch/ia64/mm/contig.c
index 63e6d49c5813..ca4d41e5f177 100644
--- a/arch/ia64/mm/contig.c
+++ b/arch/ia64/mm/contig.c
@@ -259,9 +259,11 @@ paging_init (void)
         num_physpages = 0;
         efi_memmap_walk(count_pages, &num_physpages);
 
-        max_dma = virt_to_phys((void *) MAX_DMA_ADDRESS) >> PAGE_SHIFT;
         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
+#ifdef CONFIG_ZONE_DMA
+        max_dma = virt_to_phys((void *) MAX_DMA_ADDRESS) >> PAGE_SHIFT;
         max_zone_pfns[ZONE_DMA] = max_dma;
+#endif
         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 
 #ifdef CONFIG_VIRTUAL_MEM_MAP