[PATCH] register hot-added memory to iomem resource

Register hot-added memory to iomem_resource.  With this, /proc/iomem can
show hot-added memory.

Note: kdump uses /proc/iomem to catch memory range when it is installed.
      So, kdump should be re-installed after /proc/iomem change.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 25 insertions, 0 deletions

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 83d37a401b3b..0b11a8543441 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -21,6 +21,7 @@
 #include <linux/memory_hotplug.h>
 #include <linux/highmem.h>
 #include <linux/vmalloc.h>
+#include <linux/ioport.h>
 
 #include <asm/tlbflush.h>
 
@@ -192,6 +193,27 @@ static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
         return;
 }
 
+/* add this memory to iomem resource */
+static void register_memory_resource(u64 start, u64 size)
+{
+        struct resource *res;
+
+        res = kzalloc(sizeof(struct resource), GFP_KERNEL);
+        BUG_ON(!res);
+
+        res->name = "System RAM";
+        res->start = start;
+        res->end = start + size - 1;
+        res->flags = IORESOURCE_MEM;
+        if (request_resource(&iomem_resource, res) < 0) {
+                printk("System RAM resource %llx - %llx cannot be added\n",
+                (unsigned long long)res->start, (unsigned long long)res->end);
+                kfree(res);
+        }
+}
+
+
+
 int add_memory(int nid, u64 start, u64 size)
 {
         pg_data_t *pgdat = NULL;
@@ -217,6 +239,9 @@ int add_memory(int nid, u64 start, u64 size)
         /* we online node here. we have no error path from here. */
         node_set_online(nid);
 
+        /* register this memory as resource */
+        register_memory_resource(start, size);
+
         return ret;
 error:
         /* rollback pgdat allocation and others */