x86: switch to change_page_attr_addr in ioremap_32.c
authorThomas Gleixner <tglx@linutronix.de>
Wed, 30 Jan 2008 12:34:05 +0000 (13:34 +0100)
committerIngo Molnar <mingo@elte.hu>
Wed, 30 Jan 2008 12:34:05 +0000 (13:34 +0100)
Use change_page_attr_addr() instead of change_page_attr(), which
simplifies the code significantly and matches the 64bit
implementation.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/mm/ioremap_32.c

index 213ace58a188bb3f4b5c71df151d94f891f6be70..ae7e55c8c647ffdb9d724bc6cf3b5c12d3869133 100644 (file)
@@ -6,6 +6,7 @@
  * (C) Copyright 1995 1996 Linus Torvalds
  */
 
+#include <linux/bootmem.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/module.h>
 #include <asm/pgtable.h>
 #include <asm/tlbflush.h>
 
+/*
+ * 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)
+{
+       unsigned long npages, vaddr, last_addr = phys_addr + size - 1;
+       int err, level;
+
+       /* No change for pages after the last mapping */
+       if (last_addr >= (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
+        */
+       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);
+       if (!err)
+               global_flush_tlb();
+
+       return err;
+}
+
 /*
  * Remap an arbitrary physical address space into the kernel virtual
  * address space. Needed when the kernel wants to access high addresses
@@ -33,7 +70,7 @@ void __iomem *__ioremap(unsigned long phys_addr, unsigned long size,
        void __iomem *addr;
        struct vm_struct *area;
        unsigned long offset, last_addr;
-       pgprot_t prot;
+       pgprot_t pgprot;
 
        /* Don't allow wraparound or zero size */
        last_addr = phys_addr + size - 1;
@@ -62,7 +99,7 @@ void __iomem *__ioremap(unsigned long phys_addr, unsigned long size,
                                return NULL;
        }
 
-       prot = MAKE_GLOBAL(__PAGE_KERNEL | flags);
+       pgprot = MAKE_GLOBAL(__PAGE_KERNEL | flags);
 
        /*
         * Mappings have to be page-aligned
@@ -79,11 +116,17 @@ void __iomem *__ioremap(unsigned long phys_addr, unsigned long size,
                return NULL;
        area->phys_addr = phys_addr;
        addr = (void __iomem *) area->addr;
-       if (ioremap_page_range((unsigned long) addr,
-                              (unsigned long) addr + size, phys_addr, prot)) {
+       if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size,
+                              phys_addr, pgprot)) {
                vunmap((void __force *) addr);
                return NULL;
        }
+
+       if (ioremap_change_attr(phys_addr, size, pgprot) < 0) {
+               vunmap(addr);
+               return NULL;
+       }
+
        return (void __iomem *) (offset + (char __iomem *)addr);
 }
 EXPORT_SYMBOL(__ioremap);
@@ -111,37 +154,7 @@ EXPORT_SYMBOL(__ioremap);
  */
 void __iomem *ioremap_nocache(unsigned long phys_addr, unsigned long size)
 {
-       unsigned long last_addr;
-       void __iomem *p = __ioremap(phys_addr, size, _PAGE_PCD | _PAGE_PWT);
-
-       if (!p)
-               return p;
-
-       /* Guaranteed to be > phys_addr, as per __ioremap() */
-       last_addr = phys_addr + size - 1;
-
-       if (last_addr < virt_to_phys(high_memory) - 1) {
-               struct page *ppage = virt_to_page(__va(phys_addr));
-               unsigned long npages;
-
-               phys_addr &= PAGE_MASK;
-
-               /* This might overflow and become zero.. */
-               last_addr = PAGE_ALIGN(last_addr);
-
-               /* .. but that's ok, because modulo-2**n arithmetic will make
-                * the page-aligned "last - first" come out right.
-                */
-               npages = (last_addr - phys_addr) >> PAGE_SHIFT;
-
-               if (change_page_attr(ppage, npages, PAGE_KERNEL_NOCACHE) < 0) {
-                       iounmap(p);
-                       p = NULL;
-               }
-               global_flush_tlb();
-       }
-
-       return p;
+       return __ioremap(phys_addr, size, _PAGE_PCD | _PAGE_PWT);
 }
 EXPORT_SYMBOL(ioremap_nocache);
 
@@ -189,12 +202,7 @@ void iounmap(volatile void __iomem *addr)
        }
 
        /* Reset the direct mapping. Can block */
-       if (p->phys_addr < virt_to_phys(high_memory) - 1) {
-               change_page_attr(virt_to_page(__va(p->phys_addr)),
-                                get_vm_area_size(p) >> PAGE_SHIFT,
-                                PAGE_KERNEL);
-               global_flush_tlb();
-       }
+       ioremap_change_attr(p->phys_addr, p->size, PAGE_KERNEL);
 
        /* Finally remove it */
        o = remove_vm_area((void *)addr);