From 8d1ed12f7992be24c75ad50dba140b15e89d0992 Mon Sep 17 00:00:00 2001 From: Anand Jain Date: Tue, 15 Sep 2015 16:46:23 +0800 Subject: [PATCH] btrfs-progs: optimize not to scan repeated fsid mount points fsid can be mounted multiple times, with different subvolid. And we don't have to scan a mount point if we already have that in the scanned list. And thus nicely avoids the following warning with multiple subvol mounts on older kernel like 2.6.32 where BTRFS_IOC_GET_FSLABEL ioctl does not exist. ./btrfs fi show -m Label: none uuid: 31845933-611e-422d-ae6f-386e57ad81aa Total devices 2 FS bytes used 172.00KiB devid 1 size 3.00GiB used 642.38MiB path /dev/sdd devid 2 size 3.00GiB used 622.38MiB path /dev/sde warning, device 2 is missing warning devid 2 not found already warning, device 2 is missing warning devid 2 not found already Signed-off-by: Anand Jain Signed-off-by: David Sterba --- cmds-filesystem.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/cmds-filesystem.c b/cmds-filesystem.c index 02def40a..36637347 100644 --- a/cmds-filesystem.c +++ b/cmds-filesystem.c @@ -468,6 +468,10 @@ static int btrfs_scan_kernel(void *search, unsigned unit_mode) goto out; } + /* skip all fs already shown as mounted fs */ + if (is_seen_fsid(fs_info_arg.fsid)) + continue; + ret = get_label_mounted(mnt->mnt_dir, label); /* provide backward kernel compatibility */ if (ret == -ENOTTY)