From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:42900 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751347AbeC0MVU (ORCPT ); Tue, 27 Mar 2018 08:21:20 -0400 Subject: Re: [PATCH 7/8] btrfs: verify checksum for all devices in mount context To: Anand Jain , linux-btrfs@vger.kernel.org References: <20180326082742.9235-1-anand.jain@oracle.com> <20180326082742.9235-8-anand.jain@oracle.com> From: Nikolay Borisov Message-ID: <63df7a25-7b4b-bb7e-6b85-383c3dcdc54e@suse.com> Date: Tue, 27 Mar 2018 15:21:18 +0300 MIME-Version: 1.0 In-Reply-To: <20180326082742.9235-8-anand.jain@oracle.com> Content-Type: text/plain; charset=utf-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 26.03.2018 11:27, Anand Jain wrote: > During mount context, we aren't verifying the superblock checksum > for all the devices, instead, we verify it only for the > struct btrfs_fs_device::latest_bdev. This patch fixes it > by moving the checksum verification code from the function open_ctree() > into the function btrfs_read_dev_one_super(). > > By doing this now we are verifying the superblock checksum > in the mount-context, device-replace and, device-delete context. Which call chain provides the device-replace and device-delete contexts? I think it is worth it documenting them in the changelog. > > Signed-off-by: Anand Jain Reviewed-by: Nikolay Borisov > --- > fs/btrfs/disk-io.c | 35 +++++++++++++++++------------------ > 1 file changed, 17 insertions(+), 18 deletions(-) > > diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c > index 6299ab18da5f..3cc50041c0b9 100644 > --- a/fs/btrfs/disk-io.c > +++ b/fs/btrfs/disk-io.c > @@ -2565,24 +2565,6 @@ int open_ctree(struct super_block *sb, > } > > /* > - * We want to check superblock checksum, the type is stored inside. > - * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k). > - */ > - err = btrfs_check_super_csum(bh->b_data); > - if (err) { > - if (err == -EINVAL) > - pr_err("BTRFS error (device %pg): "\ > - "unsupported checksum algorithm", > - fs_devices->latest_bdev); > - else > - pr_err("BTRFS error (device %pg): "\ > - "superblock checksum mismatch", > - fs_devices->latest_bdev); > - brelse(bh); > - goto fail_alloc; > - } > - > - /* > * super_copy is zeroed at allocation time and we never touch the > * following bytes up to INFO_SIZE, the checksum is calculated from > * the whole block of INFO_SIZE > @@ -3128,6 +3110,7 @@ int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num, > struct buffer_head *bh; > struct btrfs_super_block *super; > u64 bytenr; > + int err; > > bytenr = btrfs_sb_offset(copy_num); > if (bytenr + BTRFS_SUPER_INFO_SIZE >= i_size_read(bdev->bd_inode)) > @@ -3148,6 +3131,22 @@ int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num, > return -EINVAL; > } > > + /* > + * Check the superblock checksum, the type is stored inside. > + * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k). > + */ > + err = btrfs_check_super_csum(bh->b_data); > + if (err) { > + if (err == -EINVAL) > + pr_err("BTRFS error (device %pg): unsupported checksum algorithm", > + bdev); > + else if (err == -EUCLEAN) > + pr_err("BTRFS error (device %pg): superblock checksum mismatch", > + bdev); > + brelse(bh); > + return err; > + } > + > *bh_ret = bh; > return 0; > } >