1 files changed, 16 insertions, 15 deletions

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 8e7cafb5fc6c..a480b09c79b9 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -222,7 +222,10 @@ static int ocfs2_readpage(struct file *file, struct page *page)
                 goto out;
         }
 
-        down_read(&OCFS2_I(inode)->ip_alloc_sem);
+        if (down_read_trylock(&OCFS2_I(inode)->ip_alloc_sem) == 0) {
+                ret = AOP_TRUNCATED_PAGE;
+                goto out_meta_unlock;
+        }
 
         /*
          * i_size might have just been updated as we grabed the meta lock.  We
@@ -235,10 +238,7 @@ static int ocfs2_readpage(struct file *file, struct page *page)
          * XXX sys_readahead() seems to get that wrong?
          */
         if (start >= i_size_read(inode)) {
-                char *addr = kmap(page);
-                memset(addr, 0, PAGE_SIZE);
-                flush_dcache_page(page);
-                kunmap(page);
+                zero_user_page(page, 0, PAGE_SIZE, KM_USER0);
                 SetPageUptodate(page);
                 ret = 0;
                 goto out_alloc;
@@ -258,6 +258,7 @@ static int ocfs2_readpage(struct file *file, struct page *page)
         ocfs2_data_unlock(inode, 0);
 out_alloc:
         up_read(&OCFS2_I(inode)->ip_alloc_sem);
+out_meta_unlock:
         ocfs2_meta_unlock(inode, 0);
 out:
         if (unlock)
@@ -797,6 +798,11 @@ int ocfs2_map_and_write_splice_data(struct inode *inode,
         }
         to = from + bytes;
 
+        BUG_ON(from > PAGE_CACHE_SIZE);
+        BUG_ON(to > PAGE_CACHE_SIZE);
+        BUG_ON(from < cluster_start);
+        BUG_ON(to > cluster_end);
+
         if (wc->w_this_page_new)
                 ret = ocfs2_map_page_blocks(wc->w_this_page, p_blkno, inode,
                                             cluster_start, cluster_end, 1);
@@ -808,11 +814,6 @@ int ocfs2_map_and_write_splice_data(struct inode *inode,
                 goto out;
         }
 
-        BUG_ON(from > PAGE_CACHE_SIZE);
-        BUG_ON(to > PAGE_CACHE_SIZE);
-        BUG_ON(from > osb->s_clustersize);
-        BUG_ON(to > osb->s_clustersize);
-
         src = buf->ops->map(sp->s_pipe, buf, 1);
         dst = kmap_atomic(wc->w_this_page, KM_USER1);
         memcpy(dst + from, src + src_from, bytes);
@@ -889,6 +890,11 @@ int ocfs2_map_and_write_user_data(struct inode *inode,
 
         to = from + bytes;
 
+        BUG_ON(from > PAGE_CACHE_SIZE);
+        BUG_ON(to > PAGE_CACHE_SIZE);
+        BUG_ON(from < cluster_start);
+        BUG_ON(to > cluster_end);
+
         if (wc->w_this_page_new)
                 ret = ocfs2_map_page_blocks(wc->w_this_page, p_blkno, inode,
                                             cluster_start, cluster_end, 1);
@@ -900,11 +906,6 @@ int ocfs2_map_and_write_user_data(struct inode *inode,
                 goto out;
         }
 
-        BUG_ON(from > PAGE_CACHE_SIZE);
-        BUG_ON(to > PAGE_CACHE_SIZE);
-        BUG_ON(from > osb->s_clustersize);
-        BUG_ON(to > osb->s_clustersize);
-
         dst = kmap(wc->w_this_page);
         memcpy(dst + from, bp->b_src_buf + src_from, bytes);
         kunmap(wc->w_this_page);