Merge remote-tracking branch 'torvalds/master' into perf/core

[linux-2.6-microblaze.git] / arch / powerpc / include / asm / pte-walk.h

diff --git a/arch/powerpc/include/asm/pte-walk.h b/arch/powerpc/include/asm/pte-walk.h
index 33fa5dd..714a35f 100644 (file)
--- a/arch/powerpc/include/asm/pte-walk.h
+++ b/arch/powerpc/include/asm/pte-walk.h
@@ -31,6 +31,35 @@ static inline pte_t *find_init_mm_pte(unsigned long ea, unsigned *hshift)
        pgd_t *pgdir = init_mm.pgd;
        return __find_linux_pte(pgdir, ea, NULL, hshift);
 }
+
+/*
+ * Convert a kernel vmap virtual address (vmalloc or ioremap space) to a
+ * physical address, without taking locks. This can be used in real-mode.
+ */
+static inline phys_addr_t ppc_find_vmap_phys(unsigned long addr)
+{
+       pte_t *ptep;
+       phys_addr_t pa;
+       int hugepage_shift;
+
+       /*
+        * init_mm does not free page tables, and does not do THP. It may
+        * have huge pages from huge vmalloc / ioremap etc.
+        */
+       ptep = find_init_mm_pte(addr, &hugepage_shift);
+       if (WARN_ON(!ptep))
+               return 0;
+
+       pa = PFN_PHYS(pte_pfn(*ptep));
+
+       if (!hugepage_shift)
+               hugepage_shift = PAGE_SHIFT;
+
+       pa |= addr & ((1ul << hugepage_shift) - 1);
+
+       return pa;
+}
+
 /*
  * This is what we should always use. Any other lockless page table lookup needs
  * careful audit against THP split.