Connect to the monitor in the old namespace and use that connection for
WaitClean requests when stopping the victim mdmon instance. This allows
ping_monitor() to work post chroot().
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
It is currently possible to remove a device and re-add it without the
manager noticing, i.e. without detecting a mdstat->devcnt
container->devcnt mismatch. Introduce ping_manager() to arrange for
mdmon to run manage_container() prior to mdadm dropping the exclusive
open() on the container. Despite these precautions sysfs_read() may
still fail. If this happens invalidate container->devcnt to ensure
manage_container() runs at the next event.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The action we are waiting for may not be complete until the monitor has
had a chance to take action on the result.
The following script can now remove the device on the first attempt,
versus a few attempts with the original Wait():
#!/bin/bash
#export MDADM_NO_MDMON=1
export IMSM_DEVNAME_AS_SERIAL=1
./mdadm -Ss
./mdadm --zero-superblock /dev/loop[0-3]
echo 2 > /proc/sys/dev/raid/speed_limit_max
./mdadm --create /dev/imsm /dev/loop[0-3] -n 4 -e imsm -a md
./mdadm --create /dev/md/r1 /dev/loop[0-3] -n 4 -l 5 --force -a mdp
./mdadm --fail /dev/md/r1 /dev/loop3
./mdadm --wait /dev/md/r1
x=0
while ! ./mdadm --remove /dev/imsm /dev/loop3 > /dev/null 2>&1
do
x=$((x+1))
done
echo "removed after $x attempts"
./mdadm --add /dev/imsm /dev/loop3
Include 2 small cleanups:
* remove the almost open coded fd2devnum() in Wait() by introducing a
new utility routine stat2devnum()
* teach connect_monitor() to parse the container device from a subarray
string
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This really should be done in mdadm, not mdmon.
We ensure the device won't be suddenly commited as a hot-spare
using O_EXCL, then check the 'holders' sysfs directory
to make sure it is only in use once.
From: Dan Williams <dan.j.williams@intel.com>
1/ Block attempts to add/remove devices from container members
2/ Forward add/remove requests to containers
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Dan Williams
NeilBrown