ext4: Init the complete page while building buddy cache

(cherry picked from commit 29eaf024980e07cc01f31ae4ea5d68c917f4b7da)

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index cf4734089a6f54cfc7051e6916c98de23ec997eb..dbf6c0e52d43e9ccbe5230cdfb8f5efa232435ec 100644 (file)
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -848,6 +848,8 @@ 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;
@@ -874,7 +876,6 @@ 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,