1 files changed, 19 insertions, 9 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 119b7ccdf39b..858829d06a92 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -307,7 +307,6 @@ void free_pgd_range(struct mmu_gather *tlb,
 {
 	pgd_t *pgd;
 	unsigned long next;
-	unsigned long start;
 
 	/*
 	 * The next few lines have given us lots of grief...
@@ -351,7 +350,6 @@ void free_pgd_range(struct mmu_gather *tlb,
 	if (addr > end - 1)
 		return;
 
-	start = addr;
 	pgd = pgd_offset(tlb->mm, addr);
 	do {
 		next = pgd_addr_end(addr, end);
@@ -1394,10 +1392,20 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 				return i ? : -EFAULT;
 			}
 			if (pages) {
-				struct page *page = vm_normal_page(gate_vma, start, *pte);
+				struct page *page;
+
+				page = vm_normal_page(gate_vma, start, *pte);
+				if (!page) {
+					if (!(gup_flags & FOLL_DUMP) &&
+					     is_zero_pfn(pte_pfn(*pte)))
+						page = pte_page(*pte);
+					else {
+						pte_unmap(pte);
+						return i ? : -EFAULT;
+					}
+				}
 				pages[i] = page;
-				if (page)
-					get_page(page);
+				get_page(page);
 			}
 			pte_unmap(pte);
 			if (vmas)
@@ -1998,11 +2006,10 @@ int apply_to_page_range(struct mm_struct *mm, unsigned long addr,
 {
 	pgd_t *pgd;
 	unsigned long next;
-	unsigned long start = addr, end = addr + size;
+	unsigned long end = addr + size;
 	int err;
 
 	BUG_ON(addr >= end);
-	mmu_notifier_invalidate_range_start(mm, start, end);
 	pgd = pgd_offset(mm, addr);
 	do {
 		next = pgd_addr_end(addr, end);
@@ -2010,7 +2017,7 @@ int apply_to_page_range(struct mm_struct *mm, unsigned long addr,
 		if (err)
 			break;
 	} while (pgd++, addr = next, addr != end);
-	mmu_notifier_invalidate_range_end(mm, start, end);
+
 	return err;
 }
 EXPORT_SYMBOL_GPL(apply_to_page_range);
@@ -2620,6 +2627,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
 	swp_entry_t entry;
 	pte_t pte;
 	struct mem_cgroup *ptr = NULL;
+	int exclusive = 0;
 	int ret = 0;
 
 	if (!pte_unmap_same(mm, pmd, page_table, orig_pte))
@@ -2714,10 +2722,12 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
 	if ((flags & FAULT_FLAG_WRITE) && reuse_swap_page(page)) {
 		pte = maybe_mkwrite(pte_mkdirty(pte), vma);
 		flags &= ~FAULT_FLAG_WRITE;
+		ret |= VM_FAULT_WRITE;
+		exclusive = 1;
 	}
 	flush_icache_page(vma, page);
 	set_pte_at(mm, address, page_table, pte);
-	page_add_anon_rmap(page, vma, address);
+	do_page_add_anon_rmap(page, vma, address, exclusive);
 	/* It's better to call commit-charge after rmap is established */
 	mem_cgroup_commit_charge_swapin(page, ptr);