[PATCH 2/4] x86: efi: break efi_lookup_mapped_addr out to generic code

[Leif Lindholm <leif.lindholm@linaro.org>]

efi_lookup_mapped_addr is a handy helper function for translating
a physical address to the corresponding virtual one by scanning
through memmap.map.

This patch breaks it out into a new file for use elsewhere.

Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
---
 arch/x86/platform/efi/efi.c       |   28 ----------------------------
 drivers/firmware/efi/Makefile     |    2 +-
 drivers/firmware/efi/efi-helper.c |   33 +++++++++++++++++++++++++++++++++
 3 files changed, 34 insertions(+), 29 deletions(-)
 create mode 100644 drivers/firmware/efi/efi-helper.c

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 5ae2eb0..d1a1b6b 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -814,34 +814,6 @@ static void __init runtime_code_page_mkexec(void)
 	}
 }
 
-/*
- * We can't ioremap data in EFI boot services RAM, because we've already mapped
- * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
- * callable after efi_enter_virtual_mode and before efi_free_boot_services.
- */
-void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
-{
-	void *p;
-	if (WARN_ON(!memmap.map))
-		return NULL;
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
-		efi_memory_desc_t *md = p;
-		u64 size = md->num_pages << EFI_PAGE_SHIFT;
-		u64 end = md->phys_addr + size;
-		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
-		    md->type != EFI_BOOT_SERVICES_CODE &&
-		    md->type != EFI_BOOT_SERVICES_DATA)
-			continue;
-		if (!md->virt_addr)
-			continue;
-		if (phys_addr >= md->phys_addr && phys_addr < end) {
-			phys_addr += md->virt_addr - md->phys_addr;
-			return (__force void __iomem *)(unsigned long)phys_addr;
-		}
-	}
-	return NULL;
-}
-
 void efi_memory_uc(u64 addr, unsigned long size)
 {
 	unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index 99245ab..629a513 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -1,6 +1,6 @@
 #
 # Makefile for linux kernel
 #
-obj-y					+= efi.o vars.o
+obj-y					+= efi.o vars.o efi-helper.o
 obj-$(CONFIG_EFI_VARS)			+= efivars.o
 obj-$(CONFIG_EFI_VARS_PSTORE)		+= efi-pstore.o
diff --git a/drivers/firmware/efi/efi-helper.c b/drivers/firmware/efi/efi-helper.c
new file mode 100644
index 0000000..c5c2c72
--- /dev/null
+++ b/drivers/firmware/efi/efi-helper.c
@@ -0,0 +1,33 @@
+/*
+ * Common [U]EFI support helper functions across architectures.
+ */
+
+#include <linux/efi.h>
+
+/*
+ * We can't ioremap data in EFI boot services RAM, because we've already mapped
+ * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
+ * callable after efi_enter_virtual_mode and before efi_free_boot_services.
+ */
+void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
+{
+	void *p;
+	if (WARN_ON(!memmap.map))
+		return NULL;
+	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+		efi_memory_desc_t *md = p;
+		u64 size = md->num_pages << EFI_PAGE_SHIFT;
+		u64 end = md->phys_addr + size;
+		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
+		    md->type != EFI_BOOT_SERVICES_CODE &&
+		    md->type != EFI_BOOT_SERVICES_DATA)
+			continue;
+		if (!md->virt_addr)
+			continue;
+		if (phys_addr >= md->phys_addr && phys_addr < end) {
+			phys_addr += md->virt_addr - md->phys_addr;
+			return (__force void __iomem *)(unsigned long)phys_addr;
+		}
+	}
+	return NULL;
+}
-- 
1.7.10.4