ARM: 8432/1: move VMALLOC_END from 0xff000000 to 0xff800000

There is a 12MB unused region in our memory map between the vmalloc and
fixmap areas. This became unused with commit e9da6e9905e6, confirmed
with commit 64d3b6a3f480.

We also have a 8MB guard area before the vmalloc area.  With the default
240MB vmalloc area size and the current VMALLOC_END definition, that
means the end of low memory ends up at 0xef800000 which is unfortunate
for 768MB machines where 8MB of RAM is lost to himem.

Let's move VMALLOC_END to 0xff800000 so the guard area won't chop the
top of the 768MB low memory area while keeping the default vmalloc area
size unchanged and still preserving a gap between the vmalloc and fixmap
areas.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/Documentation/arm/memory.txt b/Documentation/arm/memory.txt
index 4178ebda6e665c1c2e9dac6451e2137acfd41eb1..546a39048eb0d6893a6d2fa81fe309bb5555ddbc 100644 (file)
--- a/Documentation/arm/memory.txt
+++ b/Documentation/arm/memory.txt
@@ -54,7 +54,7 @@ VMALLOC_START VMALLOC_END-1   vmalloc() / ioremap() space.
                                located here through iotable_init().
                                VMALLOC_START is based upon the value
                                of the high_memory variable, and VMALLOC_END
-                               is equal to 0xff000000.
+                               is equal to 0xff800000.
 
 PAGE_OFFSET    high_memory-1   Kernel direct-mapped RAM region.
                                This maps the platforms RAM, and typically

diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index f40354198bad4078717ac8933966d511c6dc130b..348caabb7625ee7b12fc0ddd8e2546b22f338b1c 100644 (file)
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -43,7 +43,7 @@
  */
 #define VMALLOC_OFFSET         (8*1024*1024)
 #define VMALLOC_START          (((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
-#define VMALLOC_END            0xff000000UL
+#define VMALLOC_END            0xff800000UL
 
 #define LIBRARY_TEXT_START     0x0c000000