From 2ebd1704ded88a8ae29b5f3998b13959c715c4be Mon Sep 17 00:00:00 2001 From: Yongqiang Yang Date: Wed, 5 Sep 2012 01:27:50 -0400 Subject: [PATCH] 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 Signed-off-by: "Theodore Ts'o" Cc: stable@vger.kernel.org --- fs/ext4/resize.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index a0ee26c23dd8..365d800ff8c1 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -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); -- 2.20.1