Merge tag 'iwlwifi-next-for-kalle-2014-12-30' of https://git.kernel.org/pub/scm/linux...

[cascardo/linux.git] / arch / x86 / mm / pageattr.c

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index dfaf2e0..536ea2f 100644 (file)
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -383,6 +383,26 @@ static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address,
         return lookup_address(address, level);
 }
 
+/*
+ * Lookup the PMD entry for a virtual address. Return a pointer to the entry
+ * or NULL if not present.
+ */
+pmd_t *lookup_pmd_address(unsigned long address)
+{
+       pgd_t *pgd;
+       pud_t *pud;
+
+       pgd = pgd_offset_k(address);
+       if (pgd_none(*pgd))
+               return NULL;
+
+       pud = pud_offset(pgd, address);
+       if (pud_none(*pud) || pud_large(*pud) || !pud_present(*pud))
+               return NULL;
+
+       return pmd_offset(pud, address);
+}
+
 /*
  * This is necessary because __pa() does not work on some
  * kinds of memory, like vmalloc() or the alloc_remap()