#!/usr/bin/env bash

set -e

rootdir=$(readlink -f $(dirname $0))/..
source "$rootdir/scripts/common.sh"

function usage()
{
	if [ `uname` = Linux ]; then
		options="[config|reset|status|help]"
	else
		options="[config|reset|help]"
	fi

	[[ ! -z $2 ]] && ( echo "$2"; echo ""; )
	echo "Helper script for allocating hugepages and binding NVMe, I/OAT and Virtio devices to"
	echo "a generic VFIO kernel driver. If VFIO is not available on the system, this script will"
	echo "fall back to UIO. NVMe and Virtio devices with active mountpoints will be ignored."
	echo "All hugepage operations use default hugepage size on the system (hugepagesz)."
	echo "Usage: $(basename $1) $options"
	echo
	echo "$options - as following:"
	echo "config            Default mode. Allocate hugepages and bind PCI devices."
	echo "reset             Rebind PCI devices back to their original drivers."
	echo "                  Also cleanup any leftover spdk files/resources."
	echo "                  Hugepage memory size will remain unchanged."
	if [ `uname` = Linux ]; then
		echo "status            Print status of all SPDK-compatible devices on the system."
	fi
	echo "help              Print this help message."
	echo
	echo "The following environment variables can be specified."
	echo "HUGEMEM           Size of hugepage memory to allocate (in MB). 2048 by default."
	echo "                  For NUMA systems, the hugepages will be evenly distributed"
	echo "                  between CPU nodes"
	echo "NRHUGE            Number of hugepages to allocate. This variable overwrites HUGEMEM."
	echo "HUGENODE          Specific NUMA node to allocate hugepages on. To allocate"
	echo "                  hugepages on multiple nodes run this script multiple times -"
	echo "                  once for each node."
	echo "NVME_WHITELIST    Whitespace separated list of NVMe devices to bind."
	echo "                  Each device must be specified as a full PCI address."
	echo "                  E.g. NVME_WHITELIST=\"0000:01:00.0 0000:02:00.0\""
	echo "                  To blacklist all NVMe devices use a non-valid PCI address."
	echo "                  E.g. NVME_WHITELIST=\"none\""
	echo "                  If empty or unset, all PCI devices will be bound."
	echo "SKIP_PCI          Setting this variable to non-zero value will skip all PCI operations."
	echo "TARGET_USER       User that will own hugepage mountpoint directory and vfio groups."
	echo "                  By default the current user will be used."
	exit 0
}

function nvme_whitelist_contains() {
	for i in ${NVME_WHITELIST[@]}
	do
		if [ "$i" == "$1" ] ; then
			 return 1
		fi
	done
	return 0
}

function linux_bind_driver() {
	bdf="$1"
	driver_name="$2"
	old_driver_name="no driver"
	ven_dev_id=$(lspci -n -s $bdf | cut -d' ' -f3 | sed 's/:/ /')

	if [ -e "/sys/bus/pci/devices/$bdf/driver" ]; then
		old_driver_name=$(basename $(readlink /sys/bus/pci/devices/$bdf/driver))

		if [ "$driver_name" = "$old_driver_name" ]; then
			return 0
		fi

		echo "$ven_dev_id" > "/sys/bus/pci/devices/$bdf/driver/remove_id" 2> /dev/null || true
		echo "$bdf" > "/sys/bus/pci/devices/$bdf/driver/unbind"
	fi

	echo "$bdf ($ven_dev_id): $old_driver_name -> $driver_name"

	echo "$ven_dev_id" > "/sys/bus/pci/drivers/$driver_name/new_id" 2> /dev/null || true
	echo "$bdf" > "/sys/bus/pci/drivers/$driver_name/bind" 2> /dev/null || true

	iommu_group=$(basename $(readlink -f /sys/bus/pci/devices/$bdf/iommu_group))
	if [ -e "/dev/vfio/$iommu_group" ]; then
		if [ -n "$TARGET_USER" ]; then
			chown "$TARGET_USER" "/dev/vfio/$iommu_group"
		fi
	fi
}

function linux_unbind_driver() {
	bdf="$1"
	ven_dev_id=$(lspci -n -s $bdf | cut -d' ' -f3 | sed 's/:/ /')

	if ! [ -e "/sys/bus/pci/devices/$bdf/driver" ]; then
		return 0
	fi

	old_driver_name=$(basename $(readlink /sys/bus/pci/devices/$bdf/driver))

	echo "$ven_dev_id" > "/sys/bus/pci/devices/$bdf/driver/remove_id" 2> /dev/null || true
	echo "$bdf" > "/sys/bus/pci/devices/$bdf/driver/unbind"
	echo "$bdf ($ven_dev_id): $old_driver_name -> no driver"
}

function linux_hugetlbfs_mounts() {
	mount | grep ' type hugetlbfs ' | awk '{ print $3 }'
}

function get_nvme_name_from_bdf {
	set +e
	nvme_devs=`lsblk -d --output NAME | grep "^nvme"`
	set -e
	for dev in $nvme_devs; do
		link_name=$(readlink /sys/block/$dev/device/device) || true
		if [ -z "$link_name" ]; then
			link_name=$(readlink /sys/block/$dev/device)
		fi
		bdf=$(basename "$link_name")
		if [ "$bdf" = "$1" ]; then
			eval "$2=$dev"
			return
		fi
	done
}

function get_virtio_names_from_bdf {
	set +e
	virtio_ctrlrs=`lsblk --nodeps --output "NAME,SUBSYSTEMS" | grep virtio | awk '{print $1}'`
	set -e
	virtio_names=''

	for ctrlr in $virtio_ctrlrs; do
		if readlink "/sys/block/$ctrlr" | grep -q "$1"; then
			virtio_names="$virtio_names $ctrlr"
		fi
	done

	eval "$2='$virtio_names'"
}

function configure_linux_pci {
	driver_name=vfio-pci
	if [ -z "$(ls /sys/kernel/iommu_groups)" ]; then
		# No IOMMU. Use uio.
		driver_name=uio_pci_generic
	fi

	# NVMe
	modprobe $driver_name || true
	for bdf in $(iter_pci_class_code 01 08 02); do
		blkname=''
		get_nvme_name_from_bdf "$bdf" blkname
		if [[ ${#NVME_WHITELIST[@]} != 0 ]] && nvme_whitelist_contains $bdf == "0" ; then
			echo "Skipping un-whitelisted NVMe controller $blkname ($bdf)"
			continue
		fi
		if [ "$blkname" != "" ]; then
			mountpoints=$(lsblk /dev/$blkname --output MOUNTPOINT -n | wc -w)
		else
			mountpoints="0"
		fi
		if [ "$mountpoints" = "0" ]; then
			linux_bind_driver "$bdf" "$driver_name"
		else
			echo Active mountpoints on /dev/$blkname, so not binding PCI dev $bdf
		fi
	done

	# IOAT
	TMP=`mktemp`
	#collect all the device_id info of ioat devices.
	grep "PCI_DEVICE_ID_INTEL_IOAT" $rootdir/include/spdk/pci_ids.h \
	| awk -F"x" '{print $2}' > $TMP

	for dev_id in `cat $TMP`; do
		for bdf in $(iter_pci_dev_id 8086 $dev_id); do
			linux_bind_driver "$bdf" "$driver_name"
		done
	done
	rm $TMP

	# virtio-scsi
	TMP=`mktemp`
	#collect all the device_id info of virtio-scsi devices.
	grep "PCI_DEVICE_ID_VIRTIO_SCSI" $rootdir/include/spdk/pci_ids.h \
	| awk -F"x" '{print $2}' > $TMP

	for dev_id in `cat $TMP`; do
		for bdf in $(iter_pci_dev_id 1af4 $dev_id); do
			blknames=''
			get_virtio_names_from_bdf "$bdf" blknames
			for blkname in $blknames; do
				if mount | grep -q "/dev/$blkname"; then
					echo Active mountpoints on /dev/$blkname, so not binding PCI dev $bdf
					continue 2
				fi
			done

			linux_bind_driver "$bdf" "$driver_name"
		done
	done
	rm $TMP

	echo "1" > "/sys/bus/pci/rescan"
}

function configure_linux {
	if [ "$SKIP_PCI" == 0 ]; then
		configure_linux_pci
	fi

	hugetlbfs_mounts=$(linux_hugetlbfs_mounts)

	if [ -z "$hugetlbfs_mounts" ]; then
		hugetlbfs_mounts=/mnt/huge
		echo "Mounting hugetlbfs at $hugetlbfs_mounts"
		mkdir -p "$hugetlbfs_mounts"
		mount -t hugetlbfs nodev "$hugetlbfs_mounts"
	fi

	if [ -z "$HUGENODE" ]; then
		hugepages_target="/proc/sys/vm/nr_hugepages"
	else
		hugepages_target="/sys/devices/system/node/node${HUGENODE}/hugepages/hugepages-${HUGEPGSZ}kB/nr_hugepages"
	fi

	echo "$NRHUGE" > "$hugepages_target"
	allocated_hugepages=`cat $hugepages_target`
	if [ "$allocated_hugepages" -lt "$NRHUGE" ]; then
		echo ""
		echo "## ERROR: requested $NRHUGE hugepages but only $allocated_hugepages could be allocated."
		echo "## Memory might be heavily fragmented. Please try flushing the system cache, or reboot the machine."
		exit 1
	fi

	if [ "$driver_name" = "vfio-pci" ]; then
		if [ -n "$TARGET_USER" ]; then
			for mount in $hugetlbfs_mounts; do
				chown "$TARGET_USER" "$mount"
				chmod g+w "$mount"
			done
		fi

		MEMLOCK_AMNT=`ulimit -l`
		if [ "$MEMLOCK_AMNT" != "unlimited" ] ; then
			MEMLOCK_MB=$(( $MEMLOCK_AMNT / 1024 ))
			echo ""
			echo "Current user memlock limit: ${MEMLOCK_MB} MB"
			echo ""
			echo "This is the maximum amount of memory you will be"
			echo "able to use with DPDK and VFIO if run as current user."
			echo -n "To change this, please adjust limits.conf memlock "
			echo "limit for current user."

			if [ $MEMLOCK_AMNT -lt 65536 ] ; then
				echo ""
				echo "## WARNING: memlock limit is less than 64MB"
				echo -n "## DPDK with VFIO may not be able to initialize "
				echo "if run as current user."
			fi
		fi
	fi
}

function reset_linux_pci {
	# NVMe
	set +e
	lsmod | grep nvme > /dev/null
	driver_loaded=$?
	set -e
	for bdf in $(iter_pci_class_code 01 08 02); do
		if [ $driver_loaded -eq 0 ]; then
			linux_bind_driver "$bdf" nvme
		else
			linux_unbind_driver "$bdf"
		fi
	done

	# IOAT
	TMP=`mktemp`
	#collect all the device_id info of ioat devices.
	grep "PCI_DEVICE_ID_INTEL_IOAT" $rootdir/include/spdk/pci_ids.h \
	| awk -F"x" '{print $2}' > $TMP

	set +e
	lsmod | grep ioatdma > /dev/null
	driver_loaded=$?
	set -e
	for dev_id in `cat $TMP`; do
		for bdf in $(iter_pci_dev_id 8086 $dev_id); do
			if [ $driver_loaded -eq 0 ]; then
				linux_bind_driver "$bdf" ioatdma
			else
				linux_unbind_driver "$bdf"
			fi
		done
	done
	rm $TMP

	# virtio-scsi
	TMP=`mktemp`
	#collect all the device_id info of virtio-scsi devices.
	grep "PCI_DEVICE_ID_VIRTIO_SCSI" $rootdir/include/spdk/pci_ids.h \
	| awk -F"x" '{print $2}' > $TMP

	# TODO: check if virtio-pci is loaded first and just unbind if it is not loaded
	# Requires some more investigation - for example, some kernels do not seem to have
	#  virtio-pci but just virtio_scsi instead.  Also need to make sure we get the
	#  underscore vs. dash right in the virtio_scsi name.
	modprobe virtio-pci || true
	for dev_id in `cat $TMP`; do
		for bdf in $(iter_pci_dev_id 1af4 $dev_id); do
			linux_bind_driver "$bdf" virtio-pci
		done
	done
	rm $TMP

	echo "1" > "/sys/bus/pci/rescan"
}

function reset_linux {
	if [ "$SKIP_PCI" == 0 ]; then
		reset_linux_pci
	fi

	for mount in $(linux_hugetlbfs_mounts); do
		rm -f "$mount"/spdk*map_*
	done
	rm -f /run/.spdk*
}

function status_linux {
	echo "NVMe devices"

	echo -e "BDF\t\tNuma Node\tDriver name\t\tDevice name"
	for bdf in $(iter_pci_class_code 01 08 02); do
		driver=`grep DRIVER /sys/bus/pci/devices/$bdf/uevent |awk -F"=" '{print $2}'`
		node=`cat /sys/bus/pci/devices/$bdf/numa_node`;
		if [ "$driver" = "nvme" -a -d /sys/bus/pci/devices/$bdf/nvme ]; then
			name="\t"`ls /sys/bus/pci/devices/$bdf/nvme`;
		else
			name="-";
		fi
		echo -e "$bdf\t$node\t\t$driver\t\t$name";
	done

	echo "I/OAT DMA"

	#collect all the device_id info of ioat devices.
	TMP=`grep "PCI_DEVICE_ID_INTEL_IOAT" $rootdir/include/spdk/pci_ids.h \
	| awk -F"x" '{print $2}'`
	echo -e "BDF\t\tNuma Node\tDriver Name"
	for dev_id in $TMP; do
		for bdf in $(iter_pci_dev_id 8086 $dev_id); do
			driver=`grep DRIVER /sys/bus/pci/devices/$bdf/uevent |awk -F"=" '{print $2}'`
			node=`cat /sys/bus/pci/devices/$bdf/numa_node`;
			echo -e "$bdf\t$node\t\t$driver"
		done
	done

	echo "virtio"

	#collect all the device_id info of virtio-scsi devices.
	TMP=`grep "PCI_DEVICE_ID_VIRTIO_SCSI" $rootdir/include/spdk/pci_ids.h \
	| awk -F"x" '{print $2}'`
	echo -e "BDF\t\tNuma Node\tDriver Name"
	for dev_id in $TMP; do
		for bdf in $(iter_pci_dev_id 1af4 $dev_id); do
			driver=`grep DRIVER /sys/bus/pci/devices/$bdf/uevent |awk -F"=" '{print $2}'`
			node=`cat /sys/bus/pci/devices/$bdf/numa_node`;
			echo -e "$bdf\t$node\t\t$driver"
		done
	done
}

function configure_freebsd_pci {
	TMP=`mktemp`

	# NVMe
	GREP_STR="class=0x010802"

	# IOAT
	grep "PCI_DEVICE_ID_INTEL_IOAT" $rootdir/include/spdk/pci_ids.h \
	| awk -F"x" '{print $2}' > $TMP
	for dev_id in `cat $TMP`; do
		GREP_STR="${GREP_STR}\|chip=0x${dev_id}8086"
	done

	AWK_PROG="{if (count > 0) printf \",\"; printf \"%s:%s:%s\",\$2,\$3,\$4; count++}"
	echo $AWK_PROG > $TMP

	BDFS=`pciconf -l | grep "${GREP_STR}" | awk -F: -f $TMP`

	kldunload nic_uio.ko || true
	kenv hw.nic_uio.bdfs=$BDFS
	kldload nic_uio.ko
	rm $TMP
}

function configure_freebsd {
	if [ "$SKIP_PCI" == 0 ]; then
		configure_freebsd_pci
	fi

	kldunload contigmem.ko || true
	kenv hw.contigmem.num_buffers=$((HUGEMEM / 256))
	kenv hw.contigmem.buffer_size=$((256 * 1024 * 1024))
	kldload contigmem.ko
}

function reset_freebsd {
	kldunload contigmem.ko || true

	if [ "$SKIP_PCI" == 0 ]; then
		kldunload nic_uio.ko || true
	fi
}

mode=$1

if [ -z "$mode" ]; then
	mode="config"
fi

: ${HUGEMEM:=2048}
: ${SKIP_PCI:=0}
: ${NVME_WHITELIST:=""}
declare -a NVME_WHITELIST=(${NVME_WHITELIST})

if [ -z "$TARGET_USER" ]; then
	TARGET_USER="$SUDO_USER"
	if [ -z "$TARGET_USER" ]; then
		TARGET_USER=`logname 2>/dev/null` || true
	fi
fi

if [ `uname` = Linux ]; then
	HUGEPGSZ=$(( `grep Hugepagesize /proc/meminfo | cut -d : -f 2 | tr -dc '0-9'` ))
	HUGEPGSZ_MB=$(( $HUGEPGSZ / 1024 ))
	: ${NRHUGE=$(( (HUGEMEM + HUGEPGSZ_MB - 1) / HUGEPGSZ_MB ))}

	if [ "$mode" == "config" ]; then
		configure_linux
	elif [ "$mode" == "reset" ]; then
		reset_linux
	elif [ "$mode" == "status" ]; then
		status_linux
	elif [ "$mode" == "help" ]; then
		usage $0
	else
		usage $0 "Invalid argument '$mode'"
	fi
else
	if [ "$mode" == "config" ]; then
		configure_freebsd
	elif [ "$mode" == "reset" ]; then
		reset_freebsd
	elif [ "$mode" == "help" ]; then
		usage $0
	else
		usage $0 "Invalid argument '$mode'"
	fi
fi