1 files changed, 35 insertions, 22 deletions

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 8777bb7688f4..b86f66fa5185 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -19,6 +19,11 @@
 #include <asm/pgtable.h>
 #include <asm/tlbflush.h>
 
+enum ioremap_mode {
+        IOR_MODE_UNCACHED,
+        IOR_MODE_CACHED,
+};
+
 #ifdef CONFIG_X86_64
 
 unsigned long __phys_addr(unsigned long x)
@@ -64,19 +69,17 @@ int page_is_ram(unsigned long pagenr)
  * Fix up the linear direct mapping of the kernel to avoid cache attribute
  * conflicts.
  */
-static int ioremap_change_attr(unsigned long phys_addr, unsigned long size,
-                               pgprot_t prot)
+static int ioremap_change_attr(unsigned long paddr, unsigned long size,
+                               enum ioremap_mode mode)
 {
-        unsigned long npages, vaddr, last_addr = phys_addr + size - 1;
+        unsigned long vaddr = (unsigned long)__va(paddr);
+        unsigned long nrpages = size >> PAGE_SHIFT;
         int err, level;
 
         /* No change for pages after the last mapping */
-        if (last_addr >= (max_pfn_mapped << PAGE_SHIFT))
+        if ((paddr + size - 1) >= (max_pfn_mapped << PAGE_SHIFT))
                 return 0;
 
-        npages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
-        vaddr = (unsigned long) __va(phys_addr);
-
         /*
          * If there is no identity map for this address,
          * change_page_attr_addr is unnecessary
@@ -84,13 +87,15 @@ static int ioremap_change_attr(unsigned long phys_addr, unsigned long size,
         if (!lookup_address(vaddr, &level))
                 return 0;
 
-        /*
-         * Must use an address here and not struct page because the
-         * phys addr can be a in hole between nodes and not have a
-         * memmap entry.
-         */
-        err = change_page_attr_addr(vaddr, npages, prot);
-
+        switch (mode) {
+        case IOR_MODE_UNCACHED:
+        default:
+                err = set_memory_uc(vaddr, nrpages);
+                break;
+        case IOR_MODE_CACHED:
+                err = set_memory_wb(vaddr, nrpages);
+                break;
+        }
         if (!err)
                 global_flush_tlb();
 
@@ -107,12 +112,12 @@ static int ioremap_change_attr(unsigned long phys_addr, unsigned long size,
  * caller shouldn't need to know that small detail.
  */
 static void __iomem *__ioremap(unsigned long phys_addr, unsigned long size,
-                               unsigned long flags)
+                               enum ioremap_mode mode)
 {
         void __iomem *addr;
         struct vm_struct *area;
         unsigned long offset, last_addr;
-        pgprot_t pgprot;
+        pgprot_t prot;
 
         /* Don't allow wraparound or zero size */
         last_addr = phys_addr + size - 1;
@@ -134,7 +139,15 @@ static void __iomem *__ioremap(unsigned long phys_addr, unsigned long size,
                         return NULL;
         }
 
-        pgprot = MAKE_GLOBAL(__PAGE_KERNEL | flags);
+        switch (mode) {
+        case IOR_MODE_UNCACHED:
+        default:
+                prot = PAGE_KERNEL_NOCACHE;
+                break;
+        case IOR_MODE_CACHED:
+                prot = PAGE_KERNEL;
+                break;
+        }
 
         /*
          * Mappings have to be page-aligned
@@ -152,12 +165,12 @@ static void __iomem *__ioremap(unsigned long phys_addr, unsigned long size,
         area->phys_addr = phys_addr;
         addr = (void __iomem *) area->addr;
         if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size,
-                               phys_addr, pgprot)) {
+                               phys_addr, prot)) {
                 remove_vm_area((void *)(PAGE_MASK & (unsigned long) addr));
                 return NULL;
         }
 
-        if (ioremap_change_attr(phys_addr, size, pgprot) < 0) {
+        if (ioremap_change_attr(phys_addr, size, mode) < 0) {
                 vunmap(addr);
                 return NULL;
         }
@@ -188,13 +201,13 @@ static void __iomem *__ioremap(unsigned long phys_addr, unsigned long size,
  */
 void __iomem *ioremap_nocache(unsigned long phys_addr, unsigned long size)
 {
-        return __ioremap(phys_addr, size, _PAGE_PCD | _PAGE_PWT);
+        return __ioremap(phys_addr, size, IOR_MODE_UNCACHED);
 }
 EXPORT_SYMBOL(ioremap_nocache);
 
 void __iomem *ioremap_cache(unsigned long phys_addr, unsigned long size)
 {
-        return __ioremap(phys_addr, size, 0);
+        return __ioremap(phys_addr, size, IOR_MODE_CACHED);
 }
 EXPORT_SYMBOL(ioremap_cache);
 
@@ -242,7 +255,7 @@ void iounmap(volatile void __iomem *addr)
         }
 
         /* Reset the direct mapping. Can block */
-        ioremap_change_attr(p->phys_addr, p->size, PAGE_KERNEL);
+        ioremap_change_attr(p->phys_addr, p->size, IOR_MODE_CACHED);
 
         /* Finally remove it */
         o = remove_vm_area((void *)addr);