[PATCH] reduce MAX_NR_ZONES: make ZONE_DMA32 optional
Make ZONE_DMA32 optional
- Add #ifdefs around ZONE_DMA32 specific code and definitions.
- Add CONFIG_ZONE_DMA32 config option and use that for x86_64
that alone needs this zone.
- Remove the use of CONFIG_DMA_IS_DMA32 and CONFIG_DMA_IS_NORMAL
for ia64 and fix up the way per node ZVCs are calculated.
- Fall back to prior GFP_ZONEMASK of 0x03 if there is no
DMA32 zone.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 03a5a6e..adae3c9 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -109,12 +109,14 @@
* <16M.
*/
ZONE_DMA,
+#ifdef CONFIG_ZONE_DMA32
/*
* x86_64 needs two ZONE_DMAs because it supports devices that are
* only able to do DMA to the lower 16M but also 32 bit devices that
* can only do DMA areas below 4G.
*/
ZONE_DMA32,
+#endif
/*
* Normal addressable memory is in ZONE_NORMAL. DMA operations can be
* performed on pages in ZONE_NORMAL if the DMA devices support
@@ -161,9 +163,13 @@
*
* NOTE! Make sure this matches the zones in <linux/gfp.h>
*/
-#define GFP_ZONEMASK 0x07
-/* #define GFP_ZONETYPES (GFP_ZONEMASK + 1) */ /* Non-loner */
-#define GFP_ZONETYPES ((GFP_ZONEMASK + 1) / 2 + 1) /* Loner */
+#define GFP_ZONETYPES ((GFP_ZONEMASK + 1) / 2 + 1) /* Loner */
+
+#ifdef CONFIG_ZONE_DMA32
+#define GFP_ZONEMASK 0x07
+#else
+#define GFP_ZONEMASK 0x03
+#endif
struct zone {
/* Fields commonly accessed by the page allocator */
@@ -429,7 +435,11 @@
static inline int is_dma32(struct zone *zone)
{
+#ifdef CONFIG_ZONE_DMA32
return zone == zone->zone_pgdat->node_zones + ZONE_DMA32;
+#else
+ return 0;
+#endif
}
static inline int is_dma(struct zone *zone)
