x86: EFI: Back efi_ioremap with init_memory_mapping instead of FIX_MAP

Impact: Fix boot failure on EFI system with large runtime memory range

Brian Maly reported that some EFI system with large runtime memory
range can not boot. Because the FIX_MAP used to map runtime memory
range is smaller than run time memory range.

This patch fixes this issue by re-implement efi_ioremap() with
init_memory_mapping().

Reported-and-tested-by: Brian Maly <bmaly@redhat.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Brian Maly <bmaly@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1236135513.6204.306.camel@yhuang-dev.sh.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 17 deletions

diff --git a/arch/x86/kernel/efi_64.c b/arch/x86/kernel/efi_64.c
index 652c5287215f..cb783b92c50c 100644
--- a/arch/x86/kernel/efi_64.c
+++ b/arch/x86/kernel/efi_64.c
@@ -99,24 +99,11 @@ void __init efi_call_phys_epilog(void)
 
 void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size)
 {
-	static unsigned pages_mapped __initdata;
-	unsigned i, pages;
-	unsigned long offset;
+	unsigned long last_map_pfn;
 
-	pages = PFN_UP(phys_addr + size) - PFN_DOWN(phys_addr);
-	offset = phys_addr & ~PAGE_MASK;
-	phys_addr &= PAGE_MASK;
-
-	if (pages_mapped + pages > MAX_EFI_IO_PAGES)
+	last_map_pfn = init_memory_mapping(phys_addr, phys_addr + size);
+	if ((last_map_pfn << PAGE_SHIFT) < phys_addr + size)
 		return NULL;
 
-	for (i = 0; i < pages; i++) {
-		__set_fixmap(FIX_EFI_IO_MAP_FIRST_PAGE - pages_mapped,
-			     phys_addr, PAGE_KERNEL);
-		phys_addr += PAGE_SIZE;
-		pages_mapped++;
-	}
-
-	return (void __iomem *)__fix_to_virt(FIX_EFI_IO_MAP_FIRST_PAGE - \
-					     (pages_mapped - pages)) + offset;
+	return (void __iomem *)__va(phys_addr);
 }