[PATCH] hot-add-mem x86_64: memory_add_physaddr_to_nid node fixup

In cases where the acpi memory-add event does not containe the pxm (node)
infomation allow the driver to look up node info based on the address.  The
acpi_get_node call returns -1 if it can't decode the pxm info, this causes
add_memory to panic.  acpi_get_node would have to decode the resource from the
handle (a lenghty proposition).  This seems to be the cleanist point to
interject the hook.

[[email protected]: build fixes]
[[email protected]: build fixes]
Signed-off-by: Keith Mannthey <[email protected]>
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Andi Kleen <[email protected]>
Signed-off-by: KAMEZAWA Hiroyuki <[email protected]>
Signed-off-by: Yasunori Goto <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

arch/ia64/mm/numa.c

@@ -16,6 +16,7 @@
 #include <linux/node.h>
 #include <linux/init.h>
 #include <linux/bootmem.h>
+#include <linux/module.h>
 #include <asm/mmzone.h>
 #include <asm/numa.h>
 
@@ -69,4 +70,21 @@ int early_pfn_to_nid(unsigned long pfn)
 
 	return 0;
 }
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+/*
+ *  SRAT information is stored in node_memblk[], then we can use SRAT
+ *  information at memory-hot-add if necessary.
+ */
+
+int memory_add_physaddr_to_nid(u64 addr)
+{
+	int nid = paddr_to_nid(addr);
+	if (nid < 0)
+		return 0;
+	return nid;
+}
+
+EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
+#endif
 #endif

arch/x86_64/mm/init.c

@@ -498,6 +498,7 @@ int memory_add_physaddr_to_nid(u64 start)
 {
 	return 0;
 }
+EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 #endif
 
 #else /* CONFIG_MEMORY_HOTPLUG */

arch/x86_64/mm/srat.c

@@ -477,3 +477,5 @@ int memory_add_physaddr_to_nid(u64 start)
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
+

drivers/acpi/acpi_memhotplug.c

@@ -238,6 +238,10 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
 			num_enabled++;
 			continue;
 		}
+
+		if (node < 0)
+			node = memory_add_physaddr_to_nid(info->start_addr);
+
 		result = add_memory(node, info->start_addr, info->length);
 		if (result)
 			continue;