linux-ext4 - Re: [PATCH 4/6] Use sb_issue_zeroout in setup_new_group

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <alpine.LFD.2.00.1009291612270.25427@dhcp-lab-213.englab.brq.redhat.com>
Date:	Wed, 29 Sep 2010 16:14:08 +0200 (CEST)
From:	Lukas Czerner <lczerner@...hat.com>
To:	Lukas Czerner <lczerner@...hat.com>
cc:	linux-ext4@...r.kernel.org, tytso@....edu, rwheeler@...hat.com,
	sandeen@...hat.com, adilger@...ger.ca, snitzer@...il.com
Subject: Re: [PATCH 4/6] Use sb_issue_zeroout in setup_new_group_blocks

Use sb_issue_zeroout to zero out inode table and descriptor table
blocks instead of old approach which involves journaling.

Signed-off-by: Lukas Czerner <lczerner@...hat.com>
---
 fs/ext4/resize.c |   46 +++++++++++++---------------------------------
 1 files changed, 13 insertions(+), 33 deletions(-)

diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index ca5c8aa..2f5e347 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -226,23 +226,13 @@ static int setup_new_group_blocks(struct super_block *sb,
 	}
 
 	/* Zero out all of the reserved backup group descriptor table blocks */
-	for (i = 0, bit = gdblocks + 1, block = start + bit;
-	     i < reserved_gdb; i++, block++, bit++) {
-		struct buffer_head *gdb;
-
-		ext4_debug("clear reserved block %#04llx (+%d)\n", block, bit);
-
-		if ((err = extend_or_restart_transaction(handle, 1, bh)))
-			goto exit_bh;
+	ext4_debug("clear inode table blocks %#04llx -> %#04llx\n",
+			block, sbi->s_itb_per_group);
+	err = sb_issue_zeroout(sb, gdblocks + start + 1, reserved_gdb,
+			       GFP_NOFS, BLKDEV_IFL_WAIT);
+	if (err)
+		goto exit_bh;
 
-		if (IS_ERR(gdb = bclean(handle, sb, block))) {
-			err = PTR_ERR(gdb);
-			goto exit_bh;
-		}
-		ext4_handle_dirty_metadata(handle, NULL, gdb);
-		ext4_set_bit(bit, bh->b_data);
-		brelse(gdb);
-	}
 	ext4_debug("mark block bitmap %#04llx (+%llu)\n", input->block_bitmap,
 		   input->block_bitmap - start);
 	ext4_set_bit(input->block_bitmap - start, bh->b_data);
@@ -251,23 +241,13 @@ static int setup_new_group_blocks(struct super_block *sb,
 	ext4_set_bit(input->inode_bitmap - start, bh->b_data);
 
 	/* Zero out all of the inode table blocks */
-	for (i = 0, block = input->inode_table, bit = block - start;
-	     i < sbi->s_itb_per_group; i++, bit++, block++) {
-		struct buffer_head *it;
-
-		ext4_debug("clear inode block %#04llx (+%d)\n", block, bit);
-
-		if ((err = extend_or_restart_transaction(handle, 1, bh)))
-			goto exit_bh;
-
-		if (IS_ERR(it = bclean(handle, sb, block))) {
-			err = PTR_ERR(it);
-			goto exit_bh;
-		}
-		ext4_handle_dirty_metadata(handle, NULL, it);
-		brelse(it);
-		ext4_set_bit(bit, bh->b_data);
-	}
+	block = input->inode_table;
+	ext4_debug("clear inode table blocks %#04llx -> %#04llx\n",
+			block, sbi->s_itb_per_group);
+	err = sb_issue_zeroout(sb, block, sbi->s_itb_per_group,
+			       GFP_NOFS, BLKDEV_IFL_WAIT);
+	if (err)
+		goto exit_bh;
 
 	if ((err = extend_or_restart_transaction(handle, 2, bh)))
 		goto exit_bh;
-- 
1.7.2.3

--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html