1 files changed, 25 insertions, 7 deletions

diff --git a/mm/memory.c b/mm/memory.c
index af82741caaa4..02e48aa0ed13 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -736,7 +736,7 @@ again:
         dst_pte = pte_alloc_map_lock(dst_mm, dst_pmd, addr, &dst_ptl);
         if (!dst_pte)
                 return -ENOMEM;
-        src_pte = pte_offset_map_nested(src_pmd, addr);
+        src_pte = pte_offset_map(src_pmd, addr);
         src_ptl = pte_lockptr(src_mm, src_pmd);
         spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
         orig_src_pte = src_pte;
@@ -767,7 +767,7 @@ again:
 
         arch_leave_lazy_mmu_mode();
         spin_unlock(src_ptl);
-        pte_unmap_nested(orig_src_pte);
+        pte_unmap(orig_src_pte);
         add_mm_rss_vec(dst_mm, rss);
         pte_unmap_unlock(orig_dst_pte, dst_ptl);
         cond_resched();
@@ -1591,7 +1591,7 @@ struct page *get_dump_page(unsigned long addr)
 }
 #endif /* CONFIG_ELF_CORE */
 
-pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
+pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr,
                         spinlock_t **ptl)
 {
         pgd_t * pgd = pgd_offset(mm, addr);
@@ -2080,7 +2080,7 @@ static inline void cow_user_page(struct page *dst, struct page *src, unsigned lo
                  * zeroes.
                  */
                 if (__copy_from_user_inatomic(kaddr, uaddr, PAGE_SIZE))
-                        memset(kaddr, 0, PAGE_SIZE);
+                        clear_page(kaddr);
                 kunmap_atomic(kaddr, KM_USER0);
                 flush_dcache_page(dst);
         } else
@@ -2108,6 +2108,7 @@ static inline void cow_user_page(struct page *dst, struct page *src, unsigned lo
 static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
                 unsigned long address, pte_t *page_table, pmd_t *pmd,
                 spinlock_t *ptl, pte_t orig_pte)
+        __releases(ptl)
 {
         struct page *old_page, *new_page;
         pte_t entry;
@@ -2627,6 +2628,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
         struct page *page, *swapcache = NULL;
         swp_entry_t entry;
         pte_t pte;
+        int locked;
         struct mem_cgroup *ptr = NULL;
         int exclusive = 0;
         int ret = 0;
@@ -2677,8 +2679,12 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
                 goto out_release;
         }
 
-        lock_page(page);
+        locked = lock_page_or_retry(page, mm, flags);
         delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
+        if (!locked) {
+                ret |= VM_FAULT_RETRY;
+                goto out_release;
+        }
 
         /*
          * Make sure try_to_free_swap or reuse_swap_page or swapoff did not
@@ -2927,7 +2933,8 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
         vmf.page = NULL;
 
         ret = vma->vm_ops->fault(vma, &vmf);
-        if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))
+        if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE |
+                            VM_FAULT_RETRY)))
                 return ret;
 
         if (unlikely(PageHWPoison(vmf.page))) {
@@ -3344,7 +3351,7 @@ int in_gate_area_no_task(unsigned long addr)
 
 #endif  /* __HAVE_ARCH_GATE_AREA */
 
-static int follow_pte(struct mm_struct *mm, unsigned long address,
+static int __follow_pte(struct mm_struct *mm, unsigned long address,
                 pte_t **ptepp, spinlock_t **ptlp)
 {
         pgd_t *pgd;
@@ -3381,6 +3388,17 @@ out:
         return -EINVAL;
 }
 
+static inline int follow_pte(struct mm_struct *mm, unsigned long address,
+                             pte_t **ptepp, spinlock_t **ptlp)
+{
+        int res;
+
+        /* (void) is needed to make gcc happy */
+        (void) __cond_lock(*ptlp,
+                           !(res = __follow_pte(mm, address, ptepp, ptlp)));
+        return res;
+}
+
 /**
  * follow_pfn - look up PFN at a user virtual address
  * @vma: memory mapping