tools/hotplug: Add an initscript to start "xl devd" in a driver domain

The removal of the udev rules highlighted that although it has been
replaced by "xl devd" there isn't an initscript to replace it.

To enable this add a --pidfile option to xl devd.

Tested on Linux by running the script in dom0 and checking the daemon
was started/stopped, but not in an actual driver domain environment
since I don't have one conveniently available. I also checked that
running without the --pidfile option still works.

Scripts mainly cribbed from the xencommons for each platform.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Roger Pau Monné <roger.pau@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad@darnok.org>
Cc: George Dunlap <george.dunlap@eu.citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>

.gitignore

@@ -133,10 +133,12 @@ tools/flask/utils/flask-set-bool
 tools/flask/utils/flask-label-pci
 tools/hotplug/common/hotplugpath.sh
 tools/hotplug/FreeBSD/rc.d/xencommons
+tools/hotplug/FreeBSD/rc.d/xendriverdomain
 tools/hotplug/Linux/init.d/sysconfig.xencommons
 tools/hotplug/Linux/init.d/xen-watchdog
 tools/hotplug/Linux/init.d/xencommons
 tools/hotplug/Linux/init.d/xendomains
+tools/hotplug/Linux/init.d/xendriverdomain
 tools/hotplug/Linux/systemd/*.conf
 tools/hotplug/Linux/systemd/*.mount
 tools/hotplug/Linux/systemd/*.socket
@@ -146,6 +148,7 @@ tools/hotplug/Linux/xen-backend.rules
 tools/hotplug/Linux/xen-hotplug-common.sh
 tools/hotplug/Linux/xendomains
 tools/hotplug/NetBSD/rc.d/xencommons
+tools/hotplug/NetBSD/rc.d/xendriverdomain
 tools/include/xen/*
 tools/include/xen-xsm/*
 tools/include/xen-foreign/*.(c|h|size)

tools/configure

@@ -2403,7 +2403,7 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
 
-ac_config_files="$ac_config_files ../config/Tools.mk hotplug/FreeBSD/rc.d/xencommons hotplug/Linux/init.d/sysconfig.xencommons hotplug/Linux/init.d/xen-watchdog hotplug/Linux/init.d/xencommons hotplug/Linux/init.d/xendomains hotplug/Linux/vif-setup hotplug/Linux/xen-hotplug-common.sh hotplug/Linux/xendomains hotplug/NetBSD/rc.d/xencommons libxl/xenlight.pc.in libxl/xlutil.pc.in"
+ac_config_files="$ac_config_files ../config/Tools.mk hotplug/FreeBSD/rc.d/xencommons hotplug/FreeBSD/rc.d/xendriverdomain hotplug/Linux/init.d/sysconfig.xencommons hotplug/Linux/init.d/xen-watchdog hotplug/Linux/init.d/xencommons hotplug/Linux/init.d/xendomains hotplug/Linux/init.d/xendriverdomain hotplug/Linux/vif-setup hotplug/Linux/xen-hotplug-common.sh hotplug/Linux/xendomains hotplug/NetBSD/rc.d/xencommons hotplug/NetBSD/rc.d/xendriverdomain libxl/xenlight.pc.in libxl/xlutil.pc.in"
 
 ac_config_headers="$ac_config_headers config.h"
 
@@ -10045,14 +10045,17 @@ do
   case $ac_config_target in
     "../config/Tools.mk") CONFIG_FILES="$CONFIG_FILES ../config/Tools.mk" ;;
     "hotplug/FreeBSD/rc.d/xencommons") CONFIG_FILES="$CONFIG_FILES hotplug/FreeBSD/rc.d/xencommons" ;;
+    "hotplug/FreeBSD/rc.d/xendriverdomain") CONFIG_FILES="$CONFIG_FILES hotplug/FreeBSD/rc.d/xendriverdomain" ;;
     "hotplug/Linux/init.d/sysconfig.xencommons") CONFIG_FILES="$CONFIG_FILES hotplug/Linux/init.d/sysconfig.xencommons" ;;
     "hotplug/Linux/init.d/xen-watchdog") CONFIG_FILES="$CONFIG_FILES hotplug/Linux/init.d/xen-watchdog" ;;
     "hotplug/Linux/init.d/xencommons") CONFIG_FILES="$CONFIG_FILES hotplug/Linux/init.d/xencommons" ;;
     "hotplug/Linux/init.d/xendomains") CONFIG_FILES="$CONFIG_FILES hotplug/Linux/init.d/xendomains" ;;
+    "hotplug/Linux/init.d/xendriverdomain") CONFIG_FILES="$CONFIG_FILES hotplug/Linux/init.d/xendriverdomain" ;;
     "hotplug/Linux/vif-setup") CONFIG_FILES="$CONFIG_FILES hotplug/Linux/vif-setup" ;;
     "hotplug/Linux/xen-hotplug-common.sh") CONFIG_FILES="$CONFIG_FILES hotplug/Linux/xen-hotplug-common.sh" ;;
     "hotplug/Linux/xendomains") CONFIG_FILES="$CONFIG_FILES hotplug/Linux/xendomains" ;;
     "hotplug/NetBSD/rc.d/xencommons") CONFIG_FILES="$CONFIG_FILES hotplug/NetBSD/rc.d/xencommons" ;;
+    "hotplug/NetBSD/rc.d/xendriverdomain") CONFIG_FILES="$CONFIG_FILES hotplug/NetBSD/rc.d/xendriverdomain" ;;
     "libxl/xenlight.pc.in") CONFIG_FILES="$CONFIG_FILES libxl/xenlight.pc.in" ;;
     "libxl/xlutil.pc.in") CONFIG_FILES="$CONFIG_FILES libxl/xlutil.pc.in" ;;
     "config.h") CONFIG_HEADERS="$CONFIG_HEADERS config.h" ;;

tools/configure.ac

@@ -8,14 +8,17 @@ AC_CONFIG_SRCDIR([libxl/libxl.c])
 AC_CONFIG_FILES([
 ../config/Tools.mk
 hotplug/FreeBSD/rc.d/xencommons
+hotplug/FreeBSD/rc.d/xendriverdomain
 hotplug/Linux/init.d/sysconfig.xencommons
 hotplug/Linux/init.d/xen-watchdog
 hotplug/Linux/init.d/xencommons
 hotplug/Linux/init.d/xendomains
+hotplug/Linux/init.d/xendriverdomain
 hotplug/Linux/vif-setup
 hotplug/Linux/xen-hotplug-common.sh
 hotplug/Linux/xendomains
 hotplug/NetBSD/rc.d/xencommons
+hotplug/NetBSD/rc.d/xendriverdomain
 libxl/xenlight.pc.in
 libxl/xlutil.pc.in
 ])

tools/hotplug/FreeBSD/Makefile

@@ -6,7 +6,7 @@ XEN_SCRIPTS = vif-bridge
 
 XEN_SCRIPT_DATA =
 
-XEN_RCD_PROG = rc.d/xencommons
+XEN_RCD_PROG = rc.d/xencommons rc.d/xendriverdomain
 
 .PHONY: all
 all:

tools/hotplug/FreeBSD/rc.d/xendriverdomain.in

@@ -0,0 +1,48 @@
+#!/bin/sh
+#
+# PROVIDE: xendriverdomain
+# REQUIRE: DAEMON
+#
+# Should be run in a driver domain, but not in domain 0.
+
+. /etc/rc.subr
+
+. /etc/xen/scripts/hotplugpath.sh
+
+LD_LIBRARY_PATH="${libdir}"
+export LD_LIBRARY_PATH
+
+name="xendriverdomain"
+start_precmd="xendriverdomain_precmd"
+start_cmd="xendriverdomain_startcmd"
+stop_cmd="xendriverdomain_stop"
+extra_commands=""
+
+XLDEVD_PIDFILE="/var/run/xldevd.pid"
+
+xendriverdomain_precmd()
+{
+	:
+}
+
+xendriverdomain_startcmd()
+{
+	printf "Starting xenservices: xl devd."
+
+	${sbindir}/xl devd --pidfile=$XLDEVD_PIDFILE ${XLDEVD_ARGS}
+
+	printf "\n"
+}
+
+xendriverdomain_stop()
+{
+	printf "Stopping xl devd.\n"
+
+	rc_pid=$(check_pidfile ${XLDEVD_PIDFILE} ${sbindir}/xl)
+
+	kill -${sig_stop:-TERM} $rc_pids
+	wait_for_pids $rc_pids
+}
+
+load_rc_config $name
+run_rc_command "$1"

tools/hotplug/Linux/Makefile

@@ -9,6 +9,8 @@ XENDOMAINS_SYSCONFIG = init.d/sysconfig.xendomains
 XENCOMMONS_INITD = init.d/xencommons
 XENCOMMONS_SYSCONFIG = init.d/sysconfig.xencommons
 
+XENDRIVERDOMAIN_INITD = init.d/xendriverdomain
+
 # Xen script dir and scripts to go there.
 XEN_SCRIPTS = vif-bridge
 XEN_SCRIPTS += vif-route
@@ -53,6 +55,7 @@ install-initd:
 	$(INSTALL_DATA) $(XENDOMAINS_SYSCONFIG) $(DESTDIR)$(SYSCONFIG_DIR)/xendomains
 	$(INSTALL_PROG) $(XENCOMMONS_INITD) $(DESTDIR)$(INITD_DIR)
 	$(INSTALL_DATA) $(XENCOMMONS_SYSCONFIG) $(DESTDIR)$(SYSCONFIG_DIR)/xencommons
+	$(INSTALL_PROG) $(XENDRIVERDOMAIN_INITD) $(DESTDIR)$(INITD_DIR)
 	$(INSTALL_PROG) init.d/xen-watchdog $(DESTDIR)$(INITD_DIR)
 
 .PHONY: install-scripts

tools/hotplug/Linux/init.d/xendriverdomain.in

@@ -0,0 +1,85 @@
+
+#!/bin/bash
+#
+# xendriverdomain    Script to start services needed in a Xen driver domain
+#
+# NOTE: This initscript is not needed on dom0.
+
+# chkconfig: 2345 70 10
+# description: Starts and stops xen driver domain daemon
+### BEGIN INIT INFO
+# Provides:          xendevd
+# Required-Start:    $syslog $remote_fs
+# Should-Start:
+# Required-Stop:     $syslog $remote_fs
+# Should-Stop:
+# Default-Start:     2 3 5
+# Default-Stop:      0 1 6
+# Short-Description: Start/stop xen driver domain daemon
+# Description:       Starts and stops the daemons neeeded for a xen driver domain
+### END INIT INFO
+
+. @XEN_SCRIPT_DIR@/hotplugpath.sh
+
+xendriverdomain_config=@CONFIG_DIR@/@CONFIG_LEAF_DIR@
+
+test -f $xendriverdomain_config/xendriverdomain && . $xendriverdomain_config/xendriverdomain
+
+XLDEVD_PIDFILE=/var/run/xldevd.pid
+
+# not running in Xen dom0 or domU
+if ! test -d /proc/xen ; then
+	exit 0
+fi
+
+# mount xenfs in dom0 or domU with a pv_ops kernel
+if test "x$1" = xstart && \
+   ! test -f /proc/xen/capabilities && \
+   ! grep '^xenfs ' /proc/mounts >/dev/null;
+then
+	mount -t xenfs xenfs /proc/xen
+fi
+
+# run this script only in domU:
+# no capabilities file in xenlinux domU kernel
+# empty capabilities file in pv_ops domU kernel
+if ! test -f /proc/xen/capabilities || \
+   grep -q "control_d" /proc/xen/capabilities ; then
+	exit 0
+fi
+
+do_start () {
+	echo Starting xl devd...
+	${sbindir}/xl devd --pidfile=$XLDEVD_PIDFILE $XLDEVD_ARGS
+}
+do_stop () {
+        echo Stopping xl devd...
+	if read 2>/dev/null <$XLDEVD_PIDFILE pid; then
+		kill $pid
+		while kill -9 $pid >/dev/null 2>&1; do sleep 0.1; done
+		rm -f $XLDEVD_PIDFILE
+	fi
+}
+
+case "$1" in
+  start)
+	do_start
+	;;
+  stop)
+	do_stop
+	;;
+  reload)
+	echo >&2 'Reload not available; use force-reload'; exit 1
+	;;
+  force-reload|restart)
+        do_stop
+	do_start
+	;;
+  *)
+	# do not advertise unreasonable commands that there is no reason
+	# to use with this device
+	echo $"Usage: $0 {start|stop|restart|force-reload}"
+	exit 1
+esac
+
+exit $?

tools/hotplug/NetBSD/Makefile

@@ -8,7 +8,7 @@ XEN_SCRIPTS += vif-bridge
 XEN_SCRIPTS += vif-ip
 
 XEN_SCRIPT_DATA =
-XEN_RCD_PROG = rc.d/xencommons rc.d/xendomains rc.d/xen-watchdog
+XEN_RCD_PROG = rc.d/xencommons rc.d/xendomains rc.d/xen-watchdog rc.d/xendriverdomain
 
 .PHONY: all
 all:

tools/hotplug/NetBSD/rc.d/xendriverdomain.in

@@ -0,0 +1,49 @@
+#!/bin/sh
+#
+# PROVIDE: xendriverdomain
+# REQUIRE: DAEMON
+#
+# Should be run in a driver domain, but not in domain 0.
+
+. /etc/rc.subr
+
+DIR=$(dirname "$0")
+. "${DIR}/xen-hotplugpath.sh"
+
+LD_LIBRARY_PATH="${libdir}"
+export LD_LIBRARY_PATH
+
+name="xendriverdomain"
+start_precmd="xendriverdomain_precmd"
+start_cmd="xendriverdomain_startcmd"
+stop_cmd="xendriverdomain_stop"
+extra_commands=""
+
+XLDEVD_PIDFILE="/var/run/xldevd.pid"
+
+xendriverdomain_precmd()
+{
+	:
+}
+
+xendriverdomain_startcmd()
+{
+	printf "Starting xenservices: xl devd."
+
+	${sbindir}/xl devd --pidfile=$XLDEVD_PIDFILE ${XLDEVD_ARGS}
+
+	printf "\n"
+}
+
+xendriverdomain_stop()
+{
+	printf "Stopping xl devd.\n"
+
+	rc_pid=$(check_pidfile ${XLDEVD_PIDFILE} ${sbindir}/xl)
+
+	kill -${sig_stop:-TERM} $rc_pids
+	wait_for_pids $rc_pids
+}
+
+load_rc_config $name
+run_rc_command "$1"

tools/libxl/xl_cmdimpl.c

@@ -473,7 +473,7 @@ out:
     flush_stream(fh);
 }
 
-static int do_daemonize(char *name)
+static int do_daemonize(char *name, const char *pidfile)
 {
     char *fullname;
     pid_t child1;
@@ -505,6 +505,31 @@ static int do_daemonize(char *name)
 
     CHK_SYSCALL(daemon(0, 1));
 
+    if (pidfile) {
+        int fd = open(pidfile, O_RDWR | O_CREAT, S_IRUSR|S_IWUSR);
+        char *pid = NULL;
+
+        if (fd == -1) {
+            perror("Unable to open pidfile");
+            exit(1);
+        }
+
+        if (asprintf(&pid, "%ld\n", (long)getpid()) == -1) {
+            perror("Formatting pid");
+            exit(1);
+        }
+
+        if (write(fd, pid, strlen(pid)) < 0) {
+            perror("Writing pid");
+            exit(1);
+        }
+
+        if ( close(fd) < 0 ) {
+            perror("Closing pidfile");
+            exit(1);
+        }
+    }
+
 out:
     return ret;
 }
@@ -2813,7 +2838,7 @@ start:
         char *name;
 
         xasprintf(&name, "xl-%s", d_config.c_info.name);
-        ret = do_daemonize(name);
+        ret = do_daemonize(name, NULL);
         free(name);
         if (ret) {
             ret = (ret == 1) ? domid : ret;
@@ -7982,15 +8007,24 @@ int main_remus(int argc, char **argv)
 int main_devd(int argc, char **argv)
 {
     int ret = 0, opt = 0, daemonize = 1;
+    const char *pidfile = NULL;
+    static const struct option opts[] = {
+        {"pidfile", 1, 0, 'p'},
+        COMMON_LONG_OPTS,
+        {0, 0, 0, 0}
+    };
 
-    SWITCH_FOREACH_OPT(opt, "F", NULL, "devd", 0) {
+    SWITCH_FOREACH_OPT(opt, "Fp:", opts, "devd", 0) {
     case 'F':
         daemonize = 0;
         break;
+    case 'p':
+        pidfile = optarg;
+        break;
     }
 
     if (daemonize) {
-        ret = do_daemonize("xldevd");
+        ret = do_daemonize("xldevd", pidfile);
         if (ret) {
             ret = (ret == 1) ? 0 : ret;
             goto out;

tools/libxl/xl_cmdtable.c

@@ -506,7 +506,8 @@ struct cmd_spec cmd_table[] = {
       &main_devd, 0, 1,
       "Daemon that listens for devices and launches backends",
       "[options]",
-      "-F                      Run in the foreground",
+      "-F                      Run in the foreground.\n"
+      "-p, --pidfile [FILE]    Write PID to pidfile when daemonizing.",
     },
 #ifdef LIBXL_HAVE_PSR_CMT
     { "psr-hwinfo",