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>

1 files changed, 3 insertions, 20 deletions

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 707d81247630..6fac793329c6 100644
--- 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);