1 files changed, 8 insertions, 15 deletions

diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c
index 4553b2c5aab4..8c199f537732 100644
--- a/mm/filemap_xip.c
+++ b/mm/filemap_xip.c
@@ -68,13 +68,12 @@ do_xip_mapping_read(struct address_space *mapping,
                 if (unlikely(IS_ERR(page))) {
                         if (PTR_ERR(page) == -ENODATA) {
                                 /* sparse */
-                                page = virt_to_page(empty_zero_page);
+                                page = ZERO_PAGE(0);
                         } else {
                                 desc->error = PTR_ERR(page);
                                 goto out;
                         }
-                } else
-                        BUG_ON(!PageUptodate(page));
+                }
 
                 /* If users can be writing to this page using arbitrary
                  * virtual addresses, take care about potential aliasing
@@ -84,8 +83,7 @@ do_xip_mapping_read(struct address_space *mapping,
                         flush_dcache_page(page);
 
                 /*
-                 * Ok, we have the page, and it's up-to-date, so
-                 * now we can copy it to user space...
+                 * Ok, we have the page, so now we can copy it to user space...
                  *
                  * The actor routine returns how many bytes were actually used..
                  * NOTE! This may not be the same as how much of a user buffer
@@ -164,7 +162,7 @@ EXPORT_SYMBOL_GPL(xip_file_sendfile);
  * xip_write
  *
  * This function walks all vmas of the address_space and unmaps the
- * empty_zero_page when found at pgoff. Should it go in rmap.c?
+ * ZERO_PAGE when found at pgoff. Should it go in rmap.c?
  */
 static void
 __xip_unmap (struct address_space * mapping,
@@ -187,7 +185,7 @@ __xip_unmap (struct address_space * mapping,
                  * We need the page_table_lock to protect us from page faults,
                  * munmap, fork, etc...
                  */
-                pte = page_check_address(virt_to_page(empty_zero_page), mm,
+                pte = page_check_address(ZERO_PAGE(address), mm,
                                          address);
                 if (!IS_ERR(pte)) {
                         /* Nuke the page table entry. */
@@ -230,7 +228,6 @@ xip_file_nopage(struct vm_area_struct * area,
 
         page = mapping->a_ops->get_xip_page(mapping, pgoff*(PAGE_SIZE/512), 0);
         if (!IS_ERR(page)) {
-                BUG_ON(!PageUptodate(page));
                 return page;
         }
         if (PTR_ERR(page) != -ENODATA)
@@ -245,12 +242,11 @@ xip_file_nopage(struct vm_area_struct * area,
                         pgoff*(PAGE_SIZE/512), 1);
                 if (IS_ERR(page))
                         return NULL;
-                BUG_ON(!PageUptodate(page));
                 /* unmap page at pgoff from all other vmas */
                 __xip_unmap(mapping, pgoff);
         } else {
-                /* not shared and writable, use empty_zero_page */
-                page = virt_to_page(empty_zero_page);
+                /* not shared and writable, use ZERO_PAGE() */
+                page = ZERO_PAGE(address);
         }
 
         return page;
@@ -319,8 +315,6 @@ __xip_file_write(struct file *filp, const char __user *buf,
                         break;
                 }
 
-                BUG_ON(!PageUptodate(page));
-
                 copied = filemap_copy_from_user(page, offset, buf, bytes);
                 flush_dcache_page(page);
                 if (likely(copied > 0)) {
@@ -435,8 +429,7 @@ xip_truncate_page(struct address_space *mapping, loff_t from)
                         return 0;
                 else
                         return PTR_ERR(page);
-        } else
-                BUG_ON(!PageUptodate(page));
+        }
         kaddr = kmap_atomic(page, KM_USER0);
         memset(kaddr + offset, 0, length);
         kunmap_atomic(kaddr, KM_USER0);