From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp1040.oracle.com ([141.146.126.69]:50705 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752000AbaBXLoZ (ORCPT ); Mon, 24 Feb 2014 06:44:25 -0500 Received: from ucsinet21.oracle.com (ucsinet21.oracle.com [156.151.31.93]) by aserp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id s1OBiN2f000450 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 24 Feb 2014 11:44:24 GMT Received: from aserz7021.oracle.com (aserz7021.oracle.com [141.146.126.230]) by ucsinet21.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s1OBiM6L017497 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Mon, 24 Feb 2014 11:44:23 GMT Received: from abhmp0004.oracle.com (abhmp0004.oracle.com [141.146.116.10]) by aserz7021.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s1OBiM41026229 for ; Mon, 24 Feb 2014 11:44:22 GMT From: Anand Jain To: linux-btrfs@vger.kernel.org Subject: [PATCH 2/3] btrfs-progs: latest_devid is not always the probed devid Date: Mon, 24 Feb 2014 19:43:38 +0800 Message-Id: <1393242219-18525-2-git-send-email-Anand.Jain@oracle.com> In-Reply-To: <1393242219-18525-1-git-send-email-Anand.Jain@oracle.com> References: <1393242219-18525-1-git-send-email-Anand.Jain@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: btrfs-progs picks the latest_dev based on first probed greatest trans-id. However below test case proofs that approach is wrong. $ mkfs.btrfs -d raid1 -m raid1 /dev/sde /dev/sdf $ modprobe -r btrfs && modprobe btrfs $ mount -o degraded /dev/sde /btrfs $ touch /btrfs/testfile && btrfs fi sync /btrfs The above steps will make /dev/sdf not part of the btrfs. and as below when you use /dev/sdf the btrfs dev stat and dev scrub picks up wrong disk $ btrfs dev stat /dev/sdf [/dev/sde].write_io_errs 0 [/dev/sde].read_io_errs 0 [/dev/sde].flush_io_errs 0 [/dev/sde].corruption_errs 0 [/dev/sde].generation_errs 0 $ btrfs scrub start -B /dev/sdf scrub done for 2e99c881-6abd-4f8a-8290-e2f8d0acc575 scrub started at Mon Feb 24 14:45:06 2014 and finished after 0 seconds total bytes scrubbed: 256.00KiB with 0 errors Signed-off-by: Anand Jain --- utils.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) diff --git a/utils.c b/utils.c index e0c750d..231031e 100644 --- a/utils.c +++ b/utils.c @@ -1646,6 +1646,11 @@ int get_fs_info(char *path, struct btrfs_ioctl_fs_info_args *fi_args, memset(fi_args, 0, sizeof(*fi_args)); if (is_block_device(path)) { + + struct btrfs_super_block *disk_super; + char *buf; + u64 devid; + /* Ensure it's mounted, then set path to the mountpoint */ fd = open(path, O_RDONLY); if (fd < 0) { @@ -1665,8 +1670,23 @@ int get_fs_info(char *path, struct btrfs_ioctl_fs_info_args *fi_args, path = mp; /* Only fill in this one device */ fi_args->num_devices = 1; - fi_args->max_id = fs_devices_mnt->latest_devid; - i = fs_devices_mnt->latest_devid; + + buf = malloc(4096); + if (!buf) { + ret = -ENOMEM; + goto out; + } + disk_super = (struct btrfs_super_block *)buf; + ret = btrfs_read_dev_super(fd, disk_super, BTRFS_SUPER_INFO_OFFSET); + if (ret < 0) { + ret = -EIO; + goto out; + } + devid = btrfs_stack_device_id(&disk_super->dev_item); + + fi_args->max_id = devid; + i = devid; + memcpy(fi_args->fsid, fs_devices_mnt->fsid, BTRFS_FSID_SIZE); close(fd); } -- 1.8.4.2