1 files changed, 28 insertions, 7 deletions

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 2ac09a5822cb..20c01f2b2e11 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -19,6 +19,7 @@
 #include <asm/pgtable.h>
 #include <asm/tlbflush.h>
 #include <asm/pgalloc.h>
+#include <asm/pat.h>
 
 #ifdef CONFIG_X86_64
 
@@ -118,6 +119,7 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size,
 {
         unsigned long pfn, offset, last_addr, vaddr;
         struct vm_struct *area;
+        unsigned long new_prot_val;
         pgprot_t prot;
 
         /* Don't allow wraparound or zero size */
@@ -151,6 +153,28 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size,
                 WARN_ON_ONCE(is_ram);
         }
 
+        /*
+         * Mappings have to be page-aligned
+         */
+        offset = phys_addr & ~PAGE_MASK;
+        phys_addr &= PAGE_MASK;
+        size = PAGE_ALIGN(last_addr+1) - phys_addr;
+
+        if (reserve_memtype(phys_addr, phys_addr + size,
+                            prot_val, &new_prot_val)) {
+                /*
+                 * Do not fallback to certain memory types with certain
+                 * requested type:
+                 * - request is uncached, return cannot be write-back
+                 */
+                if ((prot_val == _PAGE_CACHE_UC &&
+                     new_prot_val == _PAGE_CACHE_WB)) {
+                        free_memtype(phys_addr, phys_addr + size);
+                        return NULL;
+                }
+                prot_val = new_prot_val;
+        }
+
         switch (prot_val) {
         case _PAGE_CACHE_UC:
         default:
@@ -162,13 +186,6 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size,
         }
 
         /*
-         * Mappings have to be page-aligned
-         */
-        offset = phys_addr & ~PAGE_MASK;
-        phys_addr &= PAGE_MASK;
-        size = PAGE_ALIGN(last_addr+1) - phys_addr;
-
-        /*
          * Ok, go for it..
          */
         area = get_vm_area(size, VM_IOREMAP);
@@ -177,11 +194,13 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size,
         area->phys_addr = phys_addr;
         vaddr = (unsigned long) area->addr;
         if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot)) {
+                free_memtype(phys_addr, phys_addr + size);
                 free_vm_area(area);
                 return NULL;
         }
 
         if (ioremap_change_attr(vaddr, size, prot_val) < 0) {
+                free_memtype(phys_addr, phys_addr + size);
                 vunmap(area->addr);
                 return NULL;
         }
@@ -265,6 +284,8 @@ void iounmap(volatile void __iomem *addr)
                 return;
         }
 
+        free_memtype(p->phys_addr, p->phys_addr + get_vm_area_size(p));
+
         /* Finally remove it */
         o = remove_vm_area((void *)addr);
         BUG_ON(p != o || o == NULL);