[PATCH] sh: Use pfn_valid() for lazy dcache write-back on SH7705

SH7705 in extended cache mode has some left-over VALID_PAGE() cruft that it
checks when doing lazy dcache write-back.  This has been gone for some time
(the last bits were in the discontig code, which should now also be gone --
this also fixes up a build error in the non-discontig case).

pfn_valid() gives the desired behaviour, so we switch to that.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

arch/sh/mm/tlb-sh3.c

@@ -40,12 +40,17 @@ void update_mmu_cache(struct vm_area_struct * vma,
 		return;
 
 #if defined(CONFIG_SH7705_CACHE_32KB)
-	struct page *page;
-	page = pte_page(pte);
-	if (VALID_PAGE(page) && !test_bit(PG_mapped, &page->flags)) {
-		unsigned long phys = pte_val(pte) & PTE_PHYS_MASK;
-		__flush_wback_region((void *)P1SEGADDR(phys), PAGE_SIZE);
-		__set_bit(PG_mapped, &page->flags);
+	{
+		struct page *page = pte_page(pte);
+		unsigned long pfn = pte_pfn(pte);
+
+		if (pfn_valid(pfn) && !test_bit(PG_mapped, &page->flags)) {
+			unsigned long phys = pte_val(pte) & PTE_PHYS_MASK;
+
+			__flush_wback_region((void *)P1SEGADDR(phys),
+					     PAGE_SIZE);
+			__set_bit(PG_mapped, &page->flags);
+		}
 	}
 #endif
 
@@ -80,7 +85,7 @@ void __flush_tlb_page(unsigned long asid, unsigned long page)
 	 */
 	addr = MMU_TLB_ADDRESS_ARRAY | (page & 0x1F000);
 	data = (page & 0xfffe0000) | asid; /* VALID bit is off */
-	
+
 	if ((cpu_data->flags & CPU_HAS_MMU_PAGE_ASSOC)) {
 		addr |= MMU_PAGE_ASSOC_BIT;
 		ways = 1;	/* we already know the way .. */