#!/bin/sh
#
#
#     NVMe-oF (rdma, tcp, fc) OCF RA. Exports and manages NVMe targets.
#
#   (c) 2021 LINBIT HA-Solutions GmbH, written by Philipp Reisner
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of version 2 of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it would be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
#
# Further, this software is distributed without any warranty that it is
# free of the rightful claim of any third person regarding infringement
# or the like.  Any license provided herein, whether implied or
# otherwise, applies only to this software file.  Patent licenses, if
# any, provided herein do not apply to combinations of this program with
# other software, or any other product whatsoever.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write the Free Software Foundation,
# Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
#

#######################################################################
# Initialization:
: ${OCF_FUNCTIONS_DIR=${OCF_ROOT}/lib/heartbeat}
. ${OCF_FUNCTIONS_DIR}/ocf-shellfuncs

OCF_RESKEY_namespace_id_default="1"
: ${OCF_RESKEY_namespace_id=${OCF_RESKEY_namespace_id_default}}

OCF_RESKEY_nguid_default=""
: ${OCF_RESKEY_nguid=${OCF_RESKEY_nguid_default}}
#######################################################################

meta_data() {
	cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="nvmet-namespace" version="0.9">
<version>1.0</version>

<longdesc lang="en">
Manages NVMe-oF namespaces. An NVMe-oF namespace is part of an NVMe-oF target.
A namespace must be created after the subsystem. It is similar in concept to
the LUN of an iSCSI target.
</longdesc>
<shortdesc lang="en">NVMe-oF target export agent</shortdesc>

<parameters>
<parameter name="nqn" required="1" unique="1">
<longdesc lang="en">
The NVMe Qualified Name (NQN) is used to identify the remote NVMe
storage target. It is similar to an iSCSI Qualified Name
(IQN). While it is a free-form string, you should follow the convention:
nqn.2014-08.com.vendor:nvme:nvm-subsystem-sn-12345
You need to refer here to the NQN of an NVMe Subsystem your created
with the NVMeSubsystem resource agent.
</longdesc>
<shortdesc lang="en">NVMe Qualified Name</shortdesc>
<content type="string" />
</parameter>

<parameter name="namespace_id" required="0" unique="1">
<longdesc lang="en">
The NVMe namespace id (number).
</longdesc>
<shortdesc lang="en">namespace id</shortdesc>
<content type="integer" default="${OCF_RESKEY_namespace_id_default}"/>
</parameter>

<parameter name="backing_path" required="1" unique="0">
<longdesc lang="en">
The full path to the block device or file that should be exposed through this
namespace.
</longdesc>
<shortdesc lang="en">block device full path</shortdesc>
<content type="string"/>
</parameter>

<parameter name="uuid" required="1" unique="1">
<longdesc lang="en">
The UUID that should be exposed by NVMe. Create it using uuidgen. This is
necessary for the initiators to accept the namespace from the new server
after failover.
</longdesc>
<shortdesc lang="en">UUID</shortdesc>
<content type="string"/>
</parameter>

<parameter name="nguid" required="0" unique="1">
<longdesc lang="en">
NGUID stands for Namespace Globally Unique Identifier. Seems to be optional,
looks like e.g. VMWare ESXi7 uses it to identify namespaces.
Use 'uuidgen' to create it.
</longdesc>
<shortdesc lang="en">NGUID</shortdesc>
<content type="string" default="${OCF_RESKEY_nguid_default}"/>
</parameter>

</parameters>

<actions>
<action name="start"		timeout="10s" />
<action name="stop"		 timeout="10s" />
<action name="status"	   timeout="10s" interval="10s" depth="0" />
<action name="monitor"	  timeout="10s" interval="10s" depth="0" />
<action name="meta-data"	timeout="5s" />
<action name="validate-all"   timeout="10s" />
</actions>
</resource-agent>
END
}

#######################################################################

nvmet_namespace_usage() {
	cat <<END
usage: $0 {start|stop|status|monitor|validate-all|meta-data}

Expects to have a fully populated OCF RA-compliant environment set.
END
}

nvmet_namespace_start() {
	nvmet_namespace_monitor
	if [ $? =  $OCF_SUCCESS ]; then
		return $OCF_SUCCESS
	fi

	if [ ! -d ${subsys} ]; then
		ocf_log err "$subsys does not exist -- Create it with NVMeSubsystem."
		exit $OCF_ERR_GENERIC
	fi

	mkdir ${namespace}
	echo "${OCF_RESKEY_backing_path}" > ${namespace}/device_path
	echo "${OCF_RESKEY_uuid}" > ${namespace}/device_uuid
	[ "${OCF_RESKEY_nguid}" ] && echo "${OCF_RESKEY_nguid}" > ${namespace}/device_nguid
	echo 1 > ${namespace}/enable

	nvmet_namespace_monitor
}

nvmet_namespace_stop() {
	nvmet_namespace_monitor
	if [ $? -eq $OCF_NOT_RUNNING ]; then
		return $OCF_SUCCESS
	fi

	rmdir ${namespace}

	return $OCF_SUCCESS
}

nvmet_namespace_monitor() {
	[ -d ${namespace} ] || return $OCF_NOT_RUNNING
	return $OCF_SUCCESS
}

nvmet_namespace_validate() {
	if [ ! -d /sys/kernel/config/nvmet ]; then
		ocf_log err "/sys/kernel/config/nvmet does not exist -- Load the nvmet.ko linux kernel module."
		exit $OCF_ERR_INSTALLED
	fi
	subsys=/sys/kernel/config/nvmet/subsystems/${OCF_RESKEY_nqn}
	namespace=${subsys}/namespaces/${OCF_RESKEY_namespace_id}

	return $OCF_SUCCESS
}


case $1 in
  meta-data)
	meta_data
	exit $OCF_SUCCESS
	;;
  usage|help)
	nvmet_namespace_usage
	exit $OCF_SUCCESS
	;;
esac

# Everything except usage and meta-data must pass the validate test
nvmet_namespace_validate

case $__OCF_ACTION in
start)		nvmet_namespace_start;;
stop)		nvmet_namespace_stop;;
monitor|status)	nvmet_namespace_monitor;;
reload)		ocf_log info "Reloading..."
			nvmet_namespace_start
		;;
validate-all)	;;
*)		nvmet_namespace_usage
		exit $OCF_ERR_UNIMPLEMENTED
		;;
esac
rc=$?
ocf_log debug "${OCF_RESOURCE_INSTANCE} $__OCF_ACTION : $rc"
exit $rc