zfs/contrib/dracut/90zfs/mount-zfs.sh.in

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#!/bin/sh
. /lib/dracut-zfs-lib.sh
ZFS_DATASET=""
ZFS_POOL=""
case "${root}" in
zfs:*) ;;
*) return ;;
esac
Use a different technique to detect whether to mount-zfs The behavior of the Dracut module was very wrong before. The correct behavior: initramfs should not run `zfs-mount` to completion if the two generator files exist. If, however, one of them is missing, it indicates one of three cases: * The kernel command line did not specify a root ZFS file system, and another Dracut module is already handling root mount (via systemd). `mount-zfs` can run, but it will do nothing. * There is no systemd to run `sysroot.mount` to begin with. `mount-zfs` must run. * The root parameter is zfs:AUTO, which cannot be run in sysroot.mount. `mount-zfs` must run. In any of these three cases, it is safe to run `zfs-mount` to completion. `zfs-mount` must also delete itself if it determines it should not run, or else Dracut will do the insane thing of running it over and over again. Literally, the definition of insanity, doing the same thing that did not work before, expecting different results. Doing that may have had a great result before, when we had a race between devices appearing and pools being mounted, and `mount-zfs` was tasked with the full responsibility of importing the needed pool, but nowadays it is wrong behavior and should be suppressed. I deduced that self-deletion was the correct thing to do by looking at other Dracut code, because (as we all are very fully aware of) Dracut is entirely, ahem, "implementation-defined". Tested-by: @wphilips Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Manuel Amador (Rudd-O) <rudd-o@rudd-o.com> Closes #5157 Closes #5204
2016-10-06 17:26:47 +00:00
GENERATOR_FILE=/run/systemd/generator/sysroot.mount
GENERATOR_EXTENSION=/run/systemd/generator/sysroot.mount.d/zfs-enhancement.conf
if [ -e "$GENERATOR_FILE" -a -e "$GENERATOR_EXTENSION" ] ; then
# If the ZFS sysroot.mount flag exists, the initial RAM disk configured
# it to mount ZFS on root. In that case, we bail early. This flag
# file gets created by the zfs-generator program upon successful run.
info "ZFS: There is a sysroot.mount and zfs-generator has extended it."
info "ZFS: Delegating root mount to sysroot.mount."
# Let us tell the initrd to run on shutdown.
# We have a shutdown hook to run
# because we imported the pool.
need_shutdown
# We now prevent Dracut from running this thing again.
for zfsmounthook in "$hookdir"/mount/*zfs* ; do
if [ -f "$zfsmounthook" ] ; then
rm -f "$zfsmounthook"
fi
done
return
fi
Use a different technique to detect whether to mount-zfs The behavior of the Dracut module was very wrong before. The correct behavior: initramfs should not run `zfs-mount` to completion if the two generator files exist. If, however, one of them is missing, it indicates one of three cases: * The kernel command line did not specify a root ZFS file system, and another Dracut module is already handling root mount (via systemd). `mount-zfs` can run, but it will do nothing. * There is no systemd to run `sysroot.mount` to begin with. `mount-zfs` must run. * The root parameter is zfs:AUTO, which cannot be run in sysroot.mount. `mount-zfs` must run. In any of these three cases, it is safe to run `zfs-mount` to completion. `zfs-mount` must also delete itself if it determines it should not run, or else Dracut will do the insane thing of running it over and over again. Literally, the definition of insanity, doing the same thing that did not work before, expecting different results. Doing that may have had a great result before, when we had a race between devices appearing and pools being mounted, and `mount-zfs` was tasked with the full responsibility of importing the needed pool, but nowadays it is wrong behavior and should be suppressed. I deduced that self-deletion was the correct thing to do by looking at other Dracut code, because (as we all are very fully aware of) Dracut is entirely, ahem, "implementation-defined". Tested-by: @wphilips Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Manuel Amador (Rudd-O) <rudd-o@rudd-o.com> Closes #5157 Closes #5204
2016-10-06 17:26:47 +00:00
info "ZFS: No sysroot.mount exists or zfs-generator did not extend it."
info "ZFS: Mounting root with the traditional mount-zfs.sh instead."
# Delay until all required block devices are present.
udevadm settle
if [ "${root}" = "zfs:AUTO" ] ; then
ZFS_DATASET="$(find_bootfs)"
if [ $? -ne 0 ] ; then
zpool import -N -a ${ZPOOL_IMPORT_OPTS}
ZFS_DATASET="$(find_bootfs)"
if [ $? -ne 0 ] ; then
warn "ZFS: No bootfs attribute found in importable pools."
export_all || export_all "-f"
rootok=0
return 1
fi
fi
info "ZFS: Using ${ZFS_DATASET} as root."
fi
ZFS_DATASET="${ZFS_DATASET:-${root#zfs:}}"
ZFS_POOL="${ZFS_DATASET%%/*}"
if import_pool "${ZFS_POOL}" ; then
Use a different technique to detect whether to mount-zfs The behavior of the Dracut module was very wrong before. The correct behavior: initramfs should not run `zfs-mount` to completion if the two generator files exist. If, however, one of them is missing, it indicates one of three cases: * The kernel command line did not specify a root ZFS file system, and another Dracut module is already handling root mount (via systemd). `mount-zfs` can run, but it will do nothing. * There is no systemd to run `sysroot.mount` to begin with. `mount-zfs` must run. * The root parameter is zfs:AUTO, which cannot be run in sysroot.mount. `mount-zfs` must run. In any of these three cases, it is safe to run `zfs-mount` to completion. `zfs-mount` must also delete itself if it determines it should not run, or else Dracut will do the insane thing of running it over and over again. Literally, the definition of insanity, doing the same thing that did not work before, expecting different results. Doing that may have had a great result before, when we had a race between devices appearing and pools being mounted, and `mount-zfs` was tasked with the full responsibility of importing the needed pool, but nowadays it is wrong behavior and should be suppressed. I deduced that self-deletion was the correct thing to do by looking at other Dracut code, because (as we all are very fully aware of) Dracut is entirely, ahem, "implementation-defined". Tested-by: @wphilips Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Manuel Amador (Rudd-O) <rudd-o@rudd-o.com> Closes #5157 Closes #5204
2016-10-06 17:26:47 +00:00
# Let us tell the initrd to run on shutdown.
# We have a shutdown hook to run
# because we imported the pool.
need_shutdown
info "ZFS: Mounting dataset ${ZFS_DATASET}..."
if mount_dataset "${ZFS_DATASET}" ; then
ROOTFS_MOUNTED=yes
return 0
fi
fi
rootok=0