ARM: dma-mapping: get rid of setting/clearing the reserved page bit

It's unnecessary; x86 doesn't do it, and ALSA doesn't require it
anymore.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Ungerer <gerg@uclinux.org>

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 707d812..6fac793 100644 (file)
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -209,10 +209,6 @@ __dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot)
                do {
                        BUG_ON(!pte_none(*pte));
 
-                       /*
-                        * x86 does not mark the pages reserved...
-                        */
-                       SetPageReserved(page);
                        set_pte_ext(pte, mk_pte(page, prot), 0);
                        page++;
                        pte++;
@@ -257,7 +253,6 @@ static void __dma_free_remap(void *cpu_addr, size_t size)
        addr = c->vm_start;
        do {
                pte_t pte = ptep_get_and_clear(&init_mm, addr, ptep);
-               unsigned long pfn;
 
                ptep++;
                addr += PAGE_SIZE;
@@ -267,21 +262,9 @@ static void __dma_free_remap(void *cpu_addr, size_t size)
                        ptep = consistent_pte[++idx];
                }
 
-               if (!pte_none(pte) && pte_present(pte)) {
-                       pfn = pte_pfn(pte);
-
-                       if (pfn_valid(pfn)) {
-                               struct page *page = pfn_to_page(pfn);
-
-                               /*
-                                * x86 does not mark the pages reserved...
-                                */
-                               ClearPageReserved(page);
-                               continue;
-                       }
-               }
-               printk(KERN_CRIT "%s: bad page in kernel page table\n",
-                      __func__);
+               if (pte_none(pte) || !pte_present(pte))
+                       printk(KERN_CRIT "%s: bad page in kernel page table\n",
+                              __func__);
        } while (size -= PAGE_SIZE);
 
        flush_tlb_kernel_range(c->vm_start, c->vm_end);