Re: Hide rootfs filesystem in df

[Robert Milasan]

On Mon, 24 Sep 2012 14:16:16 +0000
"Bernhard Voelker" <address@hidden> wrote:

> Robert Milasan wrote:
> > On Mon, 24 Sep 2012 13:35:49 +0000
> > "Bernhard Voelker" <address@hidden> wrote:
> >
> > 
> > > Thanks for the patch.
> > > The actual patch won't be so small, because the user would
> > > want to see rootfs if "df -a" is used or when she
> > > explictly calls df for the mount point.
> >
> > Don't think that makes sense to have at all "rootfs". If you check
> > mount you'll see that there is no rootfs. I've checked mount using
> > strace and seems that it reads /proc/self/mountinfo and there is no
> > rootfs.
> >
> > Anyway, it's your choice, but has no meaning/reason being able to
> > see "rootfs" even when running "df -a".
> 
> Not quite - util-linux had also to make a change related
> to a rootfs entry in /proc/self/mountinfo:
> http://git.kernel.org/?p=utils/util-linux/util-linux.git;a=commit;h=bf91904c24c470a750a7efa8ceaed3f9e9996b6c
> 
> Have a nice day,
> Berny
> 
> 

That has been fixed, at least in 12.1 and 12.2 (even if it's not fixed
there is not rootfs entry in /proc/self/mountinfo):

from 12.1:

robert@viper:~> df 
Filesystem     1K-blocks     Used Available Use% Mounted on
rootfs         103210272  6482660  95679060   7% /
devtmpfs         1997116        4   1997112   1% /dev
tmpfs            2004924      860   2004064   1% /dev/shm
tmpfs            2004924      616   2004308   1% /run
/dev/sda5      103210272  6482660  95679060   7% /
tmpfs            2004924        0   2004924   0% /sys/fs/cgroup
tmpfs            2004924        0   2004924   0% /media
tmpfs            2004924      616   2004308   1% /var/lock
tmpfs            2004924      616   2004308   1% /var/run
buildfs          5242880        0   5242880   0% /var/tmp
/dev/sda6      369245224 40832824 309655744  12% /home
robert@viper:~> cat /proc/self/mountinfo 
18 22 0:5 / /dev rw,relatime - devtmpfs devtmpfs
rw,size=1997116k,nr_inodes=499279,mode=755 19 18 0:16 / /dev/shm
rw,relatime - tmpfs tmpfs rw 20 22 0:17 / /run rw,nosuid,nodev,relatime
- tmpfs tmpfs rw,mode=755 21 18 0:11 / /dev/pts rw,relatime - devpts
devpts rw,gid=5,mode=620,ptmxmode=000 22 1 8:5 / / rw,noatime -
ext4 /dev/sda5 rw,user_xattr,acl,barrier=1,data=ordered 23 22
0:3 / /proc rw,relatime - proc proc rw 16 22 0:15 / /sys rw,relatime -
sysfs sysfs rw 17 16 0:18 / /sys/fs/cgroup
rw,nosuid,nodev,noexec,relatime - tmpfs tmpfs rw,mode=755 24 17
0:19 / /sys/fs/cgroup/systemd rw,nosuid,nodev,noexec,relatime - cgroup
cgroup rw,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd
25 17 0:20 / /sys/fs/cgroup/cpuset rw,nosuid,nodev,noexec,relatime -
cgroup cgroup rw,cpuset 26 17 0:21 / /sys/fs/cgroup/cpu,cpuacct
rw,nosuid,nodev,noexec,relatime - cgroup cgroup rw,cpuacct,cpu 27 17
0:22 / /sys/fs/cgroup/memory rw,nosuid,nodev,noexec,relatime - cgroup
cgroup rw,memory 28 17 0:23 / /sys/fs/cgroup/devices
rw,nosuid,nodev,noexec,relatime - cgroup cgroup rw,devices 29 17
0:24 / /sys/fs/cgroup/freezer rw,nosuid,nodev,noexec,relatime - cgroup
cgroup rw,freezer 30 17 0:25 / /sys/fs/cgroup/net_cls
rw,nosuid,nodev,noexec,relatime - cgroup cgroup rw,net_cls 31 17
0:26 / /sys/fs/cgroup/blkio rw,nosuid,nodev,noexec,relatime - cgroup
cgroup rw,blkio 32 17 0:27 / /sys/fs/cgroup/perf_event
rw,nosuid,nodev,noexec,relatime - cgroup cgroup rw,perf_event 33 23
0:28 / /proc/sys/fs/binfmt_misc rw,relatime - autofs systemd-1
rw,fd=21,pgrp=1,timeout=300,minproto=5,maxproto=5,direct 34 18
0:29 / /dev/hugepages rw,relatime - hugetlbfs hugetlbfs rw 36 16
0:10 / /sys/kernel/security rw,relatime - securityfs securityfs rw 37
18 0:13 / /dev/mqueue rw,relatime - mqueue mqueue rw 35 22
0:30 / /media rw,nosuid,nodev,noexec,relatime - tmpfs tmpfs rw,mode=755
38 22 0:17 /lock /var/lock rw,nosuid,nodev,relatime - tmpfs tmpfs
rw,mode=755 39 16 0:6 / /sys/kernel/debug rw,relatime - debugfs debugfs
rw 40 22 0:17 / /var/run rw,nosuid,nodev,relatime - tmpfs tmpfs
rw,mode=755 41 22 0:31 / /var/tmp rw,noatime - tmpfs buildfs
rw,size=5242880k 42 22 8:6 / /home rw,noatime - ext4 /dev/sda6
rw,user_xattr,acl,barrier=1,data=ordered 44 16
0:33 / /sys/fs/fuse/connections rw,relatime - fusectl fusectl rw 43 42
0:32 / /home/robert/.gvfs rw,nosuid,nodev,relatime -
fuse.gvfs-fuse-daemon gvfs-fuse-daemon rw,user_id=1000,group_id=100 46
33 0:35 / /proc/sys/fs/binfmt_misc rw,relatime - binfmt_misc
binfmt_misc rw


-- 
Robert Milasan
L3 Support Engineer
SUSE Linux
address@hidden