ext4: Init the complete page while building buddy cache

We need to init the complete page during buddy cache init
by setting the contents to '1'.  Otherwise we can see the
following errors after doing an online resize of the
filesystem:

EXT4-fs error (device sdb1): ext4_mb_mark_diskspace_used:
	Allocating block 1040385 in system zone of 127 group

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 0c7e247f714c..fd2294de404c 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -846,6 +846,8 @@ static int ext4_mb_init_cache(struct page *page, char *incore)
 
         err = 0;
         first_block = page->index * blocks_per_page;
+        /* init the page  */
+        memset(page_address(page), 0xff, PAGE_CACHE_SIZE);
         for (i = 0; i < blocks_per_page; i++) {
                 int group;
                 struct ext4_group_info *grinfo;
@@ -872,7 +874,6 @@ static int ext4_mb_init_cache(struct page *page, char *incore)
                         BUG_ON(incore == NULL);
                         mb_debug("put buddy for group %u in page %lu/%x\n",
                                 group, page->index, i * blocksize);
-                        memset(data, 0xff, blocksize);
                         grinfo = ext4_get_group_info(sb, group);
                         grinfo->bb_fragments = 0;
                         memset(grinfo->bb_counters, 0,