1 files changed, 29 insertions, 45 deletions

diff --git a/arch/sh/mm/pg-sh4.c b/arch/sh/mm/pg-sh4.c
index 2fe14da1f83..f3c4b2a54fc 100644
--- a/arch/sh/mm/pg-sh4.c
+++ b/arch/sh/mm/pg-sh4.c
@@ -15,8 +15,6 @@
 #include <asm/mmu_context.h>
 #include <asm/cacheflush.h>
 
-#define CACHE_ALIAS (current_cpu_data.dcache.alias_mask)
-
 #define kmap_get_fixmap_pte(vaddr)                                     \
 	pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr))
 
@@ -68,10 +66,9 @@ static inline void kunmap_coherent(struct page *page)
  */
 void clear_user_page(void *to, unsigned long address, struct page *page)
 {
-	__set_bit(PG_mapped, &page->flags);
-
 	clear_page(to);
-	if ((((address & PAGE_MASK) ^ (unsigned long)to) & CACHE_ALIAS))
+
+	if (pages_do_alias((unsigned long)to, address & PAGE_MASK))
 		__flush_wback_region(to, PAGE_SIZE);
 }
 
@@ -79,13 +76,14 @@ void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
 		       unsigned long vaddr, void *dst, const void *src,
 		       unsigned long len)
 {
-	void *vto;
-
-	__set_bit(PG_mapped, &page->flags);
-
-	vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
-	memcpy(vto, src, len);
-	kunmap_coherent(vto);
+	if (page_mapped(page) && !test_bit(PG_dcache_dirty, &page->flags)) {
+		void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
+		memcpy(vto, src, len);
+		kunmap_coherent(vto);
+	} else {
+		memcpy(dst, src, len);
+		set_bit(PG_dcache_dirty, &page->flags);
+	}
 
 	if (vma->vm_flags & VM_EXEC)
 		flush_cache_page(vma, vaddr, page_to_pfn(page));
@@ -95,13 +93,14 @@ void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
 			 unsigned long vaddr, void *dst, const void *src,
 			 unsigned long len)
 {
-	void *vfrom;
-
-	__set_bit(PG_mapped, &page->flags);
-
-	vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
-	memcpy(dst, vfrom, len);
-	kunmap_coherent(vfrom);
+	if (page_mapped(page) && !test_bit(PG_dcache_dirty, &page->flags)) {
+		void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
+		memcpy(dst, vfrom, len);
+		kunmap_coherent(vfrom);
+	} else {
+		memcpy(dst, src, len);
+		set_bit(PG_dcache_dirty, &page->flags);
+	}
 }
 
 void copy_user_highpage(struct page *to, struct page *from,
@@ -109,14 +108,19 @@ void copy_user_highpage(struct page *to, struct page *from,
 {
 	void *vfrom, *vto;
 
-	__set_bit(PG_mapped, &to->flags);
-
 	vto = kmap_atomic(to, KM_USER1);
-	vfrom = kmap_coherent(from, vaddr);
-	copy_page(vto, vfrom);
-	kunmap_coherent(vfrom);
 
-	if (((vaddr ^ (unsigned long)vto) & CACHE_ALIAS))
+	if (page_mapped(from) && !test_bit(PG_dcache_dirty, &from->flags)) {
+		vfrom = kmap_coherent(from, vaddr);
+		copy_page(vto, vfrom);
+		kunmap_coherent(vfrom);
+	} else {
+		vfrom = kmap_atomic(from, KM_USER0);
+		copy_page(vto, vfrom);
+		kunmap_atomic(vfrom, KM_USER0);
+	}
+
+	if (pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
 		__flush_wback_region(vto, PAGE_SIZE);
 
 	kunmap_atomic(vto, KM_USER1);
@@ -124,23 +128,3 @@ void copy_user_highpage(struct page *to, struct page *from,
 	smp_wmb();
 }
 EXPORT_SYMBOL(copy_user_highpage);
-
-/*
- * For SH-4, we have our own implementation for ptep_get_and_clear
- */
-pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
-{
-	pte_t pte = *ptep;
-
-	pte_clear(mm, addr, ptep);
-	if (!pte_not_present(pte)) {
-		unsigned long pfn = pte_pfn(pte);
-		if (pfn_valid(pfn)) {
-			struct page *page = pfn_to_page(pfn);
-			struct address_space *mapping = page_mapping(page);
-			if (!mapping || !mapping_writably_mapped(mapping))
-				__clear_bit(PG_mapped, &page->flags);
-		}
-	}
-	return pte;
-}