linux-kernel - [RFC PATCH 07/17] btrfs: disable device replace in HMZONED mode

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-Id: <20180809180450.5091-8-naota@elisp.net>
Date:   Fri, 10 Aug 2018 03:04:40 +0900
From:   Naohiro Aota <naota@...sp.net>
To:     David Sterba <dsterba@...e.com>, linux-btrfs@...r.kernel.org
Cc:     Chris Mason <clm@...com>, Josef Bacik <jbacik@...com>,
        linux-kernel@...r.kernel.org, Hannes Reinecke <hare@...e.com>,
        Damien Le Moal <damien.lemoal@....com>,
        Bart Van Assche <bart.vanassche@....com>,
        Matias Bjorling <mb@...htnvm.io>,
        Naohiro Aota <naota@...sp.net>
Subject: [RFC PATCH 07/17] btrfs: disable device replace in HMZONED mode

To enable device replacing feature in HMZONED mode, we should avoid write
replicating from replace source device to replace target device so that we
do not write to a location after the position of a zone's device write
pointer. In addition, scrub process should be modified to dispatch the
write I/Os sequentially and to fill holes between the extents. Finally,
write pointers of the zones should be synchronized to match with RAID
siblings in a RAID case.

It needs more works to solve all these issues. So disable the device
replace feature in HMZONED mode for now.

Signed-off-by: Naohiro Aota <naota@...sp.net>
---
 fs/btrfs/dev-replace.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 839a35008fd8..cde61fb217db 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -416,6 +416,9 @@ int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
 	struct btrfs_device *tgt_device = NULL;
 	struct btrfs_device *src_device = NULL;

+	if (btrfs_fs_incompat(fs_info, HMZONED))
+		return -EOPNOTSUPP;
+
 	ret = btrfs_find_device_by_devspec(fs_info, srcdevid,
 					    srcdev_name, &src_device);
 	if (ret)
-- 
2.18.0