x86, mirror: x86 enabling - find mirrored memory ranges
UEFI GetMemoryMap() uses a new attribute bit to mark mirrored memory
address ranges. See UEFI 2.5 spec pages 157-158:
http://www.uefi.org/sites/default/files/resources/UEFI%202_5.pdf
On EFI enabled systems scan the memory map and tell memblock about any
mirrored ranges.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Xiexiuqi <xiexiuqi@huawei.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 39ca113..d3b95b8 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1105,6 +1105,9 @@
memblock_set_current_limit(ISA_END_ADDRESS);
memblock_x86_fill();
+ if (efi_enabled(EFI_BOOT))
+ efi_find_mirror();
+
/*
* The EFI specification says that boot service code won't be called
* after ExitBootServices(). This is, in fact, a lie.
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 3b984c3..c1c382c 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -117,6 +117,27 @@
now->tv_nsec = 0;
}
+void __init efi_find_mirror(void)
+{
+ void *p;
+ u64 mirror_size = 0, total_size = 0;
+
+ for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+ efi_memory_desc_t *md = p;
+ unsigned long long start = md->phys_addr;
+ unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
+
+ total_size += size;
+ if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
+ memblock_mark_mirror(start, size);
+ mirror_size += size;
+ }
+ }
+ if (mirror_size)
+ pr_info("Memory: %lldM/%lldM mirrored memory\n",
+ mirror_size>>20, total_size>>20);
+}
+
/*
* Tell the kernel about the EFI memory map. This might include
* more than the max 128 entries that can fit in the e820 legacy
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 2092965..5f19efe 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -96,6 +96,8 @@
#define EFI_MEMORY_WP ((u64)0x0000000000001000ULL) /* write-protect */
#define EFI_MEMORY_RP ((u64)0x0000000000002000ULL) /* read-protect */
#define EFI_MEMORY_XP ((u64)0x0000000000004000ULL) /* execute-protect */
+#define EFI_MEMORY_MORE_RELIABLE \
+ ((u64)0x0000000000010000ULL) /* higher reliability */
#define EFI_MEMORY_RUNTIME ((u64)0x8000000000000000ULL) /* range requires runtime mapping */
#define EFI_MEMORY_DESCRIPTOR_VERSION 1
@@ -868,6 +870,7 @@
extern void efi_late_init(void);
extern void efi_free_boot_services(void);
extern efi_status_t efi_query_variable_store(u32 attributes, unsigned long size);
+extern void efi_find_mirror(void);
#else
static inline void efi_late_init(void) {}
static inline void efi_free_boot_services(void) {}