[PATCH] [62/66] x86_64: Support memory hotadd without sparsemem

["Andi Kleen" <ak@xxxxxxx>]

Memory hotadd doesn't need SPARSEMEM, but can be handled by just preallocating
mem_maps. This only needs some untangling of ifdefs to enable the necessary 
code even without SPARSEMEM.

Originally from Keith Mannthey, hacked by AK.


Signed-off-by: Andi Kleen <ak@xxxxxxx>

---
 arch/x86_64/kernel/e820.c      |    2 +-
 arch/x86_64/mm/init.c          |   23 +++++++++++++++++++++--
 drivers/acpi/Kconfig           |    2 +-
 include/linux/init.h           |    3 ++-
 include/linux/memory_hotplug.h |    6 ++++--
 5 files changed, 29 insertions(+), 7 deletions(-)

Index: linux/arch/x86_64/mm/init.c
===================================================================
--- linux.orig/arch/x86_64/mm/init.c
+++ linux/arch/x86_64/mm/init.c
@@ -507,9 +507,8 @@ void __init clear_kernel_mapping(unsigne
 
 /*
  * Memory hotplug specific functions
- * These are only for non-NUMA machines right now.
  */
-#ifdef CONFIG_MEMORY_HOTPLUG
+#if defined(CONFIG_ACPI_HOTPLUG_MEMORY) || defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
 
 void online_page(struct page *page)
 {
@@ -520,6 +519,26 @@ void online_page(struct page *page)
 	num_physpages++;
 }
 
+#ifndef CONFIG_MEMORY_HOTPLUG
+/* 
+ * Memory Hotadd without sparsemem. The mem_maps have been allocated in advance,
+ * just online the pages.
+ */
+int __add_pages(struct zone *z, unsigned long start_pfn, unsigned long nr_pages)
+{
+	int err = -EIO;
+	unsigned long pfn;
+	for (pfn = start_pfn; pfn < start_pfn + nr_pages; pfn++) {
+		unsigned long addr = pfn << PAGE_SHIFT;
+		if (pfn_valid(pfn) && e820_mapped(addr, addr+1, E820_RAM)) {
+			online_page(pfn_to_page(pfn));
+			err = 0;
+		}
+	}
+	return err;
+}
+#endif
+
 int add_memory(u64 start, u64 size)
 {
 	struct pglist_data *pgdat = NODE_DATA(0);
Index: linux/drivers/acpi/Kconfig
===================================================================
--- linux.orig/drivers/acpi/Kconfig
+++ linux/drivers/acpi/Kconfig
@@ -316,7 +316,7 @@ config ACPI_CONTAINER
 config ACPI_HOTPLUG_MEMORY
 	tristate "Memory Hotplug"
 	depends on ACPI
-	depends on MEMORY_HOTPLUG
+	depends on MEMORY_HOTPLUG || X86_64
 	default n
 	help
 	  This driver adds supports for ACPI Memory Hotplug.  This driver
Index: linux/include/linux/memory_hotplug.h
===================================================================
--- linux.orig/include/linux/memory_hotplug.h
+++ linux/include/linux/memory_hotplug.h
@@ -58,8 +58,6 @@ extern int add_one_highpage(struct page 
 /* need some defines for these for archs that don't support it */
 extern void online_page(struct page *page);
 /* VM interface that may be used by firmware interface */
-extern int add_memory(u64 start, u64 size);
-extern int remove_memory(u64 start, u64 size);
 extern int online_pages(unsigned long, unsigned long);
 
 /* reasonably generic interface to expand the physical pages in a zone  */
@@ -105,4 +103,8 @@ static inline int __remove_pages(struct 
 	dump_stack();
 	return -ENOSYS;
 }
+
+extern int add_memory(u64 start, u64 size);
+extern int remove_memory(u64 start, u64 size);
+
 #endif /* __LINUX_MEMORY_HOTPLUG_H */
Index: linux/include/linux/init.h
===================================================================
--- linux.orig/include/linux/init.h
+++ linux/include/linux/init.h
@@ -241,7 +241,8 @@ void __init parse_early_param(void);
 #define __cpuexitdata	__exitdata
 #endif
 
-#ifdef CONFIG_MEMORY_HOTPLUG
+#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_ACPI_HOTPLUG_MEMORY) \
+	|| defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
 #define __meminit
 #define __meminitdata
 #define __memexit
Index: linux/arch/x86_64/kernel/e820.c
===================================================================
--- linux.orig/arch/x86_64/kernel/e820.c
+++ linux/arch/x86_64/kernel/e820.c
@@ -80,7 +80,7 @@ static inline int bad_addr(unsigned long
 	return 0;
 } 
 
-int __init e820_mapped(unsigned long start, unsigned long end, unsigned type) 
+int __meminit e820_mapped(unsigned long start, unsigned long end, unsigned type) 
 { 
 	int i;
 	for (i = 0; i < e820.nr_map; i++) { 
-
: send the line "unsubscribe linux-x86_64" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html