ext4: avoid duplicate writes of the backup bg descriptor blocks

The resize code was needlessly writing the backup block group
descriptor blocks multiple times (once per block group) during an
online resize.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
This commit is contained in:
Yongqiang Yang 2012-09-05 01:27:50 -04:00 committed by Theodore Ts'o
parent 6df935ad2f
commit 2ebd1704de

View File

@ -1358,13 +1358,15 @@ exit_journal:
err = err2;
if (!err) {
int i;
int gdb_num = group / EXT4_DESC_PER_BLOCK(sb);
int gdb_num_end = ((group + flex_gd->count - 1) /
EXT4_DESC_PER_BLOCK(sb));
update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es,
sizeof(struct ext4_super_block));
for (i = 0; i < flex_gd->count; i++, group++) {
for (; gdb_num <= gdb_num_end; gdb_num++) {
struct buffer_head *gdb_bh;
int gdb_num;
gdb_num = group / EXT4_BLOCKS_PER_GROUP(sb);
gdb_bh = sbi->s_group_desc[gdb_num];
update_backups(sb, gdb_bh->b_blocknr, gdb_bh->b_data,
gdb_bh->b_size);