X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Fmemory.c;h=156861fcac436e4716537c7e5dff565dded43224;hb=d73468533451fd896324058d9ba649c11ba3e3ee;hp=601159a46ab64e538dc1c2cbe710776e3ecb5208;hpb=fecf3404f4aba6d0edeba31eeb018cbb6326dff2;p=linux-2.6

diff --git a/mm/memory.c b/mm/memory.c
index 601159a46a..156861fcac 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -467,7 +467,7 @@ copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 	 */
 	if (is_cow_mapping(vm_flags)) {
 		ptep_set_wrprotect(src_mm, addr, src_pte);
-		pte = *src_pte;
+		pte = pte_wrprotect(pte);
 	}
 
 	/*
@@ -506,6 +506,7 @@ again:
 	src_pte = pte_offset_map_nested(src_pmd, addr);
 	src_ptl = pte_lockptr(src_mm, src_pmd);
 	spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
+	arch_enter_lazy_mmu_mode();
 
 	do {
 		/*
@@ -527,6 +528,7 @@ again:
 		progress += 8;
 	} while (dst_pte++, src_pte++, addr += PAGE_SIZE, addr != end);
 
+	arch_leave_lazy_mmu_mode();
 	spin_unlock(src_ptl);
 	pte_unmap_nested(src_pte - 1);
 	add_mm_rss(dst_mm, rss[0], rss[1]);
@@ -628,6 +630,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
 	int anon_rss = 0;
 
 	pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
+	arch_enter_lazy_mmu_mode();
 	do {
 		pte_t ptent = *pte;
 		if (pte_none(ptent)) {
@@ -690,10 +693,11 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
 			continue;
 		if (!pte_file(ptent))
 			free_swap_and_cache(pte_to_swp_entry(ptent));
-		pte_clear_full(mm, addr, pte, tlb->fullmm);
+		pte_clear_not_present_full(mm, addr, pte, tlb->fullmm);
 	} while (pte++, addr += PAGE_SIZE, (addr != end && *zap_work > 0));
 
 	add_mm_rss(mm, file_rss, anon_rss);
+	arch_leave_lazy_mmu_mode();
 	pte_unmap_unlock(pte - 1, ptl);
 
 	return addr;
@@ -1082,6 +1086,7 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 				default:
 					BUG();
 				}
+				cond_resched();
 			}
 			if (pages) {
 				pages[i] = page;
@@ -1109,6 +1114,7 @@ static int zeromap_pte_range(struct mm_struct *mm, pmd_t *pmd,
 	pte = pte_alloc_map_lock(mm, pmd, addr, &ptl);
 	if (!pte)
 		return -ENOMEM;
+	arch_enter_lazy_mmu_mode();
 	do {
 		struct page *page = ZERO_PAGE(addr);
 		pte_t zero_pte = pte_wrprotect(mk_pte(page, prot));
@@ -1118,6 +1124,7 @@ static int zeromap_pte_range(struct mm_struct *mm, pmd_t *pmd,
 		BUG_ON(!pte_none(*pte));
 		set_pte_at(mm, addr, pte, zero_pte);
 	} while (pte++, addr += PAGE_SIZE, addr != end);
+	arch_leave_lazy_mmu_mode();
 	pte_unmap_unlock(pte - 1, ptl);
 	return 0;
 }
@@ -1275,11 +1282,13 @@ static int remap_pte_range(struct mm_struct *mm, pmd_t *pmd,
 	pte = pte_alloc_map_lock(mm, pmd, addr, &ptl);
 	if (!pte)
 		return -ENOMEM;
+	arch_enter_lazy_mmu_mode();
 	do {
 		BUG_ON(!pte_none(*pte));
 		set_pte_at(mm, addr, pte, pfn_pte(pfn, prot));
 		pfn++;
 	} while (pte++, addr += PAGE_SIZE, addr != end);
+	arch_leave_lazy_mmu_mode();
 	pte_unmap_unlock(pte - 1, ptl);
 	return 0;
 }
@@ -1443,6 +1452,7 @@ static inline void cow_user_page(struct page *dst, struct page *src, unsigned lo
 		if (__copy_from_user_inatomic(kaddr, uaddr, PAGE_SIZE))
 			memset(kaddr, 0, PAGE_SIZE);
 		kunmap_atomic(kaddr, KM_USER0);
+		flush_dcache_page(dst);
 		return;
 		
 	}
@@ -1577,7 +1587,14 @@ gotten:
 		entry = mk_pte(new_page, vma->vm_page_prot);
 		entry = maybe_mkwrite(pte_mkdirty(entry), vma);
 		lazy_mmu_prot_update(entry);
-		ptep_establish(vma, address, page_table, entry);
+		/*
+		 * Clear the pte entry and flush it first, before updating the
+		 * pte with the new entry. This will avoid a race condition
+		 * seen in the presence of one thread doing SMC and another
+		 * thread doing COW.
+		 */
+		ptep_clear_flush(vma, address, page_table);
+		set_pte_at(mm, address, page_table, entry);
 		update_mmu_cache(vma, address, entry);
 		lru_cache_add_active(new_page);
 		page_add_new_anon_rmap(new_page, vma, address);
@@ -2154,11 +2171,13 @@ retry:
 	 * after the next truncate_count read.
 	 */
 
-	/* no page was available -- either SIGBUS or OOM */
-	if (new_page == NOPAGE_SIGBUS)
+	/* no page was available -- either SIGBUS, OOM or REFAULT */
+	if (unlikely(new_page == NOPAGE_SIGBUS))
 		return VM_FAULT_SIGBUS;
-	if (new_page == NOPAGE_OOM)
+	else if (unlikely(new_page == NOPAGE_OOM))
 		return VM_FAULT_OOM;
+	else if (unlikely(new_page == NOPAGE_REFAULT))
+		return VM_FAULT_MINOR;
 
 	/*
 	 * Should we do an early C-O-W break?