1 files changed, 52 insertions, 8 deletions

diff --git a/mm/memory.c b/mm/memory.c
index ef09f0acb1d..e7066e71dfa 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -678,7 +678,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
 				if (pte_dirty(ptent))
 					set_page_dirty(page);
 				if (pte_young(ptent))
-					mark_page_accessed(page);
+					SetPageReferenced(page);
 				file_rss--;
 			}
 			page_remove_rmap(page, vma);
@@ -1277,6 +1277,51 @@ int vm_insert_page(struct vm_area_struct *vma, unsigned long addr, struct page *
 }
 EXPORT_SYMBOL(vm_insert_page);
 
+/**
+ * vm_insert_pfn - insert single pfn into user vma
+ * @vma: user vma to map to
+ * @addr: target user address of this page
+ * @pfn: source kernel pfn
+ *
+ * Similar to vm_inert_page, this allows drivers to insert individual pages
+ * they've allocated into a user vma. Same comments apply.
+ *
+ * This function should only be called from a vm_ops->fault handler, and
+ * in that case the handler should return NULL.
+ */
+int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
+		unsigned long pfn)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	int retval;
+	pte_t *pte, entry;
+	spinlock_t *ptl;
+
+	BUG_ON(!(vma->vm_flags & VM_PFNMAP));
+	BUG_ON(is_cow_mapping(vma->vm_flags));
+
+	retval = -ENOMEM;
+	pte = get_locked_pte(mm, addr, &ptl);
+	if (!pte)
+		goto out;
+	retval = -EBUSY;
+	if (!pte_none(*pte))
+		goto out_unlock;
+
+	/* Ok, finally just insert the thing.. */
+	entry = pfn_pte(pfn, vma->vm_page_prot);
+	set_pte_at(mm, addr, pte, entry);
+	update_mmu_cache(vma, addr, entry);
+
+	retval = 0;
+out_unlock:
+	pte_unmap_unlock(pte, ptl);
+
+out:
+	return retval;
+}
+EXPORT_SYMBOL(vm_insert_pfn);
+
 /*
  * maps a range of physical memory into the requested pages. the old
  * mappings are removed. any references to nonexistent pages results
@@ -1531,8 +1576,6 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 			if (vma->vm_ops->page_mkwrite(vma, old_page) < 0)
 				goto unwritable_page;
 
-			page_cache_release(old_page);
-
 			/*
 			 * Since we dropped the lock we need to revalidate
 			 * the PTE as someone else may have changed it.  If
@@ -1541,6 +1584,7 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 			 */
 			page_table = pte_offset_map_lock(mm, pmd, address,
 							 &ptl);
+			page_cache_release(old_page);
 			if (!pte_same(*page_table, orig_pte))
 				goto unlock;
 		}
@@ -1776,9 +1820,7 @@ restart:
 }
 
 /**
- * unmap_mapping_range - unmap the portion of all mmaps
- * in the specified address_space corresponding to the specified
- * page range in the underlying file.
+ * unmap_mapping_range - unmap the portion of all mmaps in the specified address_space corresponding to the specified page range in the underlying file.
  * @mapping: the address space containing mmaps to be unmapped.
  * @holebegin: byte in first page to unmap, relative to the start of
  * the underlying file.  This will be rounded down to a PAGE_SIZE
@@ -2313,10 +2355,12 @@ static noinline int do_no_pfn(struct mm_struct *mm, struct vm_area_struct *vma,
 	BUG_ON(is_cow_mapping(vma->vm_flags));
 
 	pfn = vma->vm_ops->nopfn(vma, address & PAGE_MASK);
-	if (pfn == NOPFN_OOM)
+	if (unlikely(pfn == NOPFN_OOM))
 		return VM_FAULT_OOM;
-	if (pfn == NOPFN_SIGBUS)
+	else if (unlikely(pfn == NOPFN_SIGBUS))
 		return VM_FAULT_SIGBUS;
+	else if (unlikely(pfn == NOPFN_REFAULT))
+		return VM_FAULT_MINOR;
 
 	page_table = pte_offset_map_lock(mm, pmd, address, &ptl);