Update from product codes

[profile/mobile/platform/kernel/linux-3.10-sc7730.git] / fs / ext4 / inode.c

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index e48bd5a..d4d7265 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -626,6 +626,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
                status = map->m_flags & EXT4_MAP_UNWRITTEN ?
                                EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
                if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) &&
+                   !(status & EXTENT_STATUS_WRITTEN) &&
                    ext4_find_delalloc_range(inode, map->m_lblk,
                                             map->m_lblk + map->m_len - 1))
                        status |= EXTENT_STATUS_DELAYED;
@@ -736,6 +737,7 @@ found:
                status = map->m_flags & EXT4_MAP_UNWRITTEN ?
                                EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
                if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) &&
+                   !(status & EXTENT_STATUS_WRITTEN) &&
                    ext4_find_delalloc_range(inode, map->m_lblk,
                                             map->m_lblk + map->m_len - 1))
                        status |= EXTENT_STATUS_DELAYED;
@@ -1030,7 +1032,8 @@ retry_journal:
                ext4_journal_stop(handle);
                goto retry_grab;
        }
-       wait_on_page_writeback(page);
+       /* In case writeback began while the page was unlocked */
+       wait_for_stable_page(page);
 
        if (ext4_should_dioread_nolock(inode))
                ret = __block_write_begin(page, pos, len, ext4_get_block_write);
@@ -2096,19 +2099,32 @@ static int __ext4_journalled_writepage(struct page *page,
                ext4_walk_page_buffers(handle, page_bufs, 0, len,
                                       NULL, bget_one);
        }
-       /* As soon as we unlock the page, it can go away, but we have
-        * references to buffers so we are safe */
+       /*
+        * We need to release the page lock before we start the
+        * journal, so grab a reference so the page won't disappear
+        * out from under us.
+        */
+       get_page(page);
        unlock_page(page);
 
        handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE,
                                    ext4_writepage_trans_blocks(inode));
        if (IS_ERR(handle)) {
                ret = PTR_ERR(handle);
-               goto out;
+               put_page(page);
+               goto out_no_pagelock;
        }
-
        BUG_ON(!ext4_handle_valid(handle));
 
+       lock_page(page);
+       put_page(page);
+       if (page->mapping != mapping) {
+               /* The page got truncated from under us */
+               ext4_journal_stop(handle);
+               ret = 0;
+               goto out;
+       }
+
        if (inline_data) {
                ret = ext4_journal_get_write_access(handle, inode_bh);
 
@@ -2133,6 +2149,8 @@ static int __ext4_journalled_writepage(struct page *page,
                                       NULL, bput_one);
        ext4_set_inode_state(inode, EXT4_STATE_JDATA);
 out:
+       unlock_page(page);
+out_no_pagelock:
        brelse(inode_bh);
        return ret;
 }
@@ -2727,7 +2745,7 @@ retry_journal:
                goto retry_grab;
        }
        /* In case writeback began while the page was unlocked */
-       wait_on_page_writeback(page);
+       wait_for_stable_page(page);
 
        ret = __block_write_begin(page, pos, len, ext4_da_get_block_prep);
        if (ret < 0) {