[patch 02/12 v4] efi: add a wrapper function efi_map_region_fixed

[patch 02/12 v4] efi: add a wrapper function efi_map_region_fixed

[dyoung]

Hi,
References: <20131125085630.417850406@dhcp-16-126.nay.redhat.com>
Content-Disposition: inline; filename=02-efi-map-fixed-addr.patch

Kexec kernel will use saved runtime virtual mapping, so add a
new function efi_map_region_fixed for directly mapping a md
to md->virt.

The md is passed in from 1st kernel, the virtual addr is
saved in md->virt_addr.

Matt: coding style
      reuse __map_region
Boris: Strenthen comment lines to 80 cols.

Signed-off-by: Dave Young <dyoung@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
---
 arch/x86/include/asm/efi.h     |    1 +
 arch/x86/platform/efi/efi_32.c |    2 ++
 arch/x86/platform/efi/efi_64.c |   10 ++++++++++
 3 files changed, 13 insertions(+)

--- efi.orig/arch/x86/include/asm/efi.h
+++ efi/arch/x86/include/asm/efi.h
@@ -128,6 +128,7 @@ extern void efi_call_phys_epilog(void);
 extern void efi_unmap_memmap(void);
 extern void efi_memory_uc(u64 addr, unsigned long size);
 extern void __init efi_map_region(efi_memory_desc_t *md);
+extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
 extern void efi_sync_low_kernel_mappings(void);
 extern void efi_setup_page_tables(void);
 extern void __init old_map_region(efi_memory_desc_t *md);
--- efi.orig/arch/x86/platform/efi/efi_64.c
+++ efi/arch/x86/platform/efi/efi_64.c
@@ -199,6 +199,16 @@ void __init efi_map_region(efi_memory_de
 	md->virt_addr = efi_va;
 }
 
+/*
+ * kexec kernel will use efi_map_region_fixed to map efi runtime memory ranges.
+ * md->virt_addr is the original virtual address which had been mapped in kexec
+ * 1st kernel.
+ */
+void __init efi_map_region_fixed(efi_memory_desc_t *md)
+{
+	__map_region(md, md->virt_addr);
+}
+
 void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size,
 				 u32 type, u64 attribute)
 {
--- efi.orig/arch/x86/platform/efi/efi_32.c
+++ efi/arch/x86/platform/efi/efi_32.c
@@ -47,6 +47,8 @@ void __init efi_map_region(efi_memory_de
 	old_map_region(md);
 }
 
+void __init efi_map_region_fixed(efi_memory_desc_t *md) {}
+
 void efi_call_phys_prelog(void)
 {
 	struct desc_ptr gdt_descr;