From: Yinghai Lu <yinghai@kernel.org>
Date: Wed, 25 May 2011 00:12:37 +0000 (-0700)
Subject: memblock/nobootmem: allow alloc_bootmem() to take 0 as low limit
X-Git-Tag: MMI-PSA29.97-13-9~19546
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=8bba154ef29e16331e578029e9050c74b87b7ff9;p=GitHub%2FMotorolaMobilityLLC%2Fkernel-slsi.git

memblock/nobootmem: allow alloc_bootmem() to take 0 as low limit

The bootmem wrapper with memblock supports top-down now, so we do not need
to set the low limit to __pa(MAX_DMA_ADDRESS).

The logic should be: good to allocate above __pa(MAX_DMA_ADDRESS), but it
is ok if we can not find memory above 16M on system that has a small
amount of RAM.

Signed-off-by: Yinghai LU <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Olaf Hering <olaf@aepfle.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/include/linux/bootmem.h b/include/linux/bootmem.h
index 01eca1794e14..ab344a521105 100644
--- a/include/linux/bootmem.h
+++ b/include/linux/bootmem.h
@@ -99,24 +99,31 @@ extern void *__alloc_bootmem_low_node(pg_data_t *pgdat,
 				      unsigned long align,
 				      unsigned long goal);
 
+#ifdef CONFIG_NO_BOOTMEM
+/* We are using top down, so it is safe to use 0 here */
+#define BOOTMEM_LOW_LIMIT 0
+#else
+#define BOOTMEM_LOW_LIMIT __pa(MAX_DMA_ADDRESS)
+#endif
+
 #define alloc_bootmem(x) \
-	__alloc_bootmem(x, SMP_CACHE_BYTES, __pa(MAX_DMA_ADDRESS))
+	__alloc_bootmem(x, SMP_CACHE_BYTES, BOOTMEM_LOW_LIMIT)
 #define alloc_bootmem_align(x, align) \
-	__alloc_bootmem(x, align, __pa(MAX_DMA_ADDRESS))
+	__alloc_bootmem(x, align, BOOTMEM_LOW_LIMIT)
 #define alloc_bootmem_nopanic(x) \
-	__alloc_bootmem_nopanic(x, SMP_CACHE_BYTES, __pa(MAX_DMA_ADDRESS))
+	__alloc_bootmem_nopanic(x, SMP_CACHE_BYTES, BOOTMEM_LOW_LIMIT)
 #define alloc_bootmem_pages(x) \
-	__alloc_bootmem(x, PAGE_SIZE, __pa(MAX_DMA_ADDRESS))
+	__alloc_bootmem(x, PAGE_SIZE, BOOTMEM_LOW_LIMIT)
 #define alloc_bootmem_pages_nopanic(x) \
-	__alloc_bootmem_nopanic(x, PAGE_SIZE, __pa(MAX_DMA_ADDRESS))
+	__alloc_bootmem_nopanic(x, PAGE_SIZE, BOOTMEM_LOW_LIMIT)
 #define alloc_bootmem_node(pgdat, x) \
-	__alloc_bootmem_node(pgdat, x, SMP_CACHE_BYTES, __pa(MAX_DMA_ADDRESS))
+	__alloc_bootmem_node(pgdat, x, SMP_CACHE_BYTES, BOOTMEM_LOW_LIMIT)
 #define alloc_bootmem_node_nopanic(pgdat, x) \
-	__alloc_bootmem_node_nopanic(pgdat, x, SMP_CACHE_BYTES, __pa(MAX_DMA_ADDRESS))
+	__alloc_bootmem_node_nopanic(pgdat, x, SMP_CACHE_BYTES, BOOTMEM_LOW_LIMIT)
 #define alloc_bootmem_pages_node(pgdat, x) \
-	__alloc_bootmem_node(pgdat, x, PAGE_SIZE, __pa(MAX_DMA_ADDRESS))
+	__alloc_bootmem_node(pgdat, x, PAGE_SIZE, BOOTMEM_LOW_LIMIT)
 #define alloc_bootmem_pages_node_nopanic(pgdat, x) \
-	__alloc_bootmem_node_nopanic(pgdat, x, PAGE_SIZE, __pa(MAX_DMA_ADDRESS))
+	__alloc_bootmem_node_nopanic(pgdat, x, PAGE_SIZE, BOOTMEM_LOW_LIMIT)
 
 #define alloc_bootmem_low(x) \
 	__alloc_bootmem_low(x, SMP_CACHE_BYTES, 0)