[POWERPC] Add arch-specific walk_memory_remove() for 64-bit powerpc

walk_memory_resource() verifies if there are holes in a given memory
range, by checking against /proc/iomem.  On x86/ia64 system memory is
represented in /proc/iomem.  On powerpc, we don't show system memory as
IO resource in /proc/iomem - instead it's maintained in
/proc/device-tree.

This provides a way for an architecture to provide its own
walk_memory_resource() function.  On powerpc, the memory region is
small (16MB), contiguous and non-overlapping.  So extra checking
against the device-tree is not needed.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <galak@gate.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/kernel/resource.c b/kernel/resource.c
index 2eb553d9b517..82aea814d409 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -228,7 +228,7 @@ int release_resource(struct resource *old)
 
 EXPORT_SYMBOL(release_resource);
 
-#ifdef CONFIG_MEMORY_HOTPLUG
+#if defined(CONFIG_MEMORY_HOTPLUG) && !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
 /*
  * Finds the lowest memory reosurce exists within [res->start.res->end)
  * the caller must specify res->start, res->end, res->flags.