[ARM] Convert pmd_page() to be highmem safe

In the long run, we may want to place page tables in highmem.  However,
pmd_page() has traditionally been coded to convert the physical address
to a virtual one, which won't work with highmem pages.  Instead,
translate the physical address to a PFN, and then convert the PFN to a
struct page instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index 110295c..1cd2d64 100644 (file)
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -342,7 +342,7 @@ static inline pte_t *pmd_page_vaddr(pmd_t pmd)
        return __va(ptr);
 }
 
-#define pmd_page(pmd) virt_to_page(__va(pmd_val(pmd)))
+#define pmd_page(pmd)          pfn_to_page(__phys_to_pfn(pmd_val(pmd)))
 
 /*
  * Conversion functions: convert a page and protection to a page entry,