alpine: Add Hyper-V daemons to the build

The daemons allow proper shutdown of a VM, heartbeats,
inquiring and setting the network configuratio etc etc.

They are only started with running in a Hyper-V VM

Signed-off-by: Rolf Neugebauer <rolf.neugebauer@docker.com>

alpine/Dockerfile

@@ -41,6 +41,13 @@ COPY packages/database/etc /etc/
 COPY packages/hupper/hupper /bin/
 COPY packages/hupper/etc /etc/
 COPY packages/hostlog/etc /etc/
+COPY packages/hvtools/hv_fcopy_daemon /sbin/
+COPY packages/hvtools/hv_kvp_daemon /sbin/
+COPY packages/hvtools/hv_vss_daemon /sbin/
+COPY packages/hvtools/etc /etc/
+COPY packages/hvtools/hv_get_dhcp_info /sbin/
+COPY packages/hvtools/hv_get_dns_info /sbin/
+COPY packages/hvtools/hv_set_ifconfig /sbin/
 
 RUN \
   rc-update add swap boot && \
@@ -77,6 +84,9 @@ RUN \
   rc-update add database boot && \
   rc-update add hupper default && \
   rc-update add hostlog default && \
+  rc-update add hv_fcopy_daemon default && \
+  rc-update add hv_kvp_daemon default && \
+  rc-update add hv_vss_daemon default && \
   ln -s /bin/busybox /init
 
 CMD ["/bin/sh"]

alpine/packages/Makefile

@@ -4,6 +4,7 @@ all:
 	$(MAKE) -C mdnstool
 	$(MAKE) -C docker
 	$(MAKE) -C hupper
+	$(MAKE) -C hvtools
 
 arm:
 	$(MAKE) -C 9pudc ARCH=arm
@@ -18,3 +19,4 @@ clean:
 	$(MAKE) -C mdnstool clean
 	$(MAKE) -C docker clean
 	$(MAKE) -C hupper clean
+	$(MAKE) -C hvtools clean

alpine/packages/hvtools/Dockerfile

@@ -0,0 +1,10 @@
+FROM alpine:3.3
+
+RUN apk update && apk upgrade && apk add alpine-sdk linux-headers
+
+RUN mkdir -p /hvtools
+WORKDIR /hvtools
+
+COPY src /hvtools/
+
+RUN make

alpine/packages/hvtools/Makefile

@@ -0,0 +1,12 @@
+all: hvtools
+
+hvtools: Dockerfile src/*
+	docker build -t hvtools:build .
+	docker run hvtools:build cat /hvtools/hv_fcopy_daemon > hv_fcopy_daemon
+	docker run hvtools:build cat /hvtools/hv_kvp_daemon > hv_kvp_daemon
+	docker run hvtools:build cat /hvtools/hv_vss_daemon > hv_vss_daemon
+	chmod 755 hv_fcopy_daemon hv_kvp_daemon hv_vss_daemon
+
+clean:
+	rm -f hv_fcopy_daemon hv_kvp_daemon hv_vss_daemon
+	docker images -q hvtools:build | xargs docker rmi -f

alpine/packages/hvtools/README.md

@@ -0,0 +1,3 @@
+# Hyper-V guest tools and daemons
+
+This package contains a copy of the ./tools/hv directory of the matching Linux kernel source in ./src. At the top level directory are customised versions of the various scripts used by the daemons.

alpine/packages/hvtools/etc/init.d/hv_fcopy_daemon

@@ -0,0 +1,32 @@
+#!/sbin/openrc-run
+
+HV_DAEMON=hv_fcopy_daemon
+
+start()
+{
+        [ ! -d /sys/bus/vmbus ] && exit 0
+
+        ebegin "Starting Hyper-V Daemon: ${HV_DAEMON}"
+
+        [ -n "${PIDFILE}" ] || PIDFILE=/var/run/${HV_DAEMON}.pid
+
+        start-stop-daemon --start --quiet \
+                --background \
+                --exec /sbin/${HV_DAEMON} \
+                --make-pidfile --pidfile ${PIDFILE} \
+                --
+        eend 0
+}
+
+stop()
+{
+        [ ! -d /sys/bus/vmbus ] && exit 0
+
+        ebegin "Stopping Hyper-V Daemon: ${HV_DAEMON}"
+
+        [ -n "${PIDFILE}" ] || PIDFILE=/var/run/${HV_DAEMON}.pid
+
+        start-stop-daemon --stop --quiet --pidfile ${PIDFILE}
+
+        eend $? "Failed to stop ${HV_DAEMON}"
+}

alpine/packages/hvtools/etc/init.d/hv_kvp_daemon

@@ -0,0 +1,32 @@
+#!/sbin/openrc-run
+
+HV_DAEMON=hv_kvp_daemon
+
+start()
+{
+        [ ! -d /sys/bus/vmbus ] && exit 0
+
+        ebegin "Starting Hyper-V Daemon: ${HV_DAEMON}"
+
+        [ -n "${PIDFILE}" ] || PIDFILE=/var/run/${HV_DAEMON}.pid
+
+        start-stop-daemon --start --quiet \
+                --background \
+                --exec /sbin/${HV_DAEMON} \
+                --make-pidfile --pidfile ${PIDFILE} \
+                --
+        eend 0
+}
+
+stop()
+{
+        [ ! -d /sys/bus/vmbus ] && exit 0
+
+        ebegin "Stopping Hyper-V Daemon: ${HV_DAEMON}"
+
+        [ -n "${PIDFILE}" ] || PIDFILE=/var/run/${HV_DAEMON}.pid
+
+        start-stop-daemon --stop --quiet --pidfile ${PIDFILE}
+
+        eend $? "Failed to stop ${HV_DAEMON}"
+}

alpine/packages/hvtools/etc/init.d/hv_vss_daemon

@@ -0,0 +1,32 @@
+#!/sbin/openrc-run
+
+HV_DAEMON=hv_vss_daemon
+
+start()
+{
+        [ ! -d /sys/bus/vmbus ] && exit 0
+
+        ebegin "Starting Hyper-V Daemon: ${HV_DAEMON}"
+
+        [ -n "${PIDFILE}" ] || PIDFILE=/var/run/${HV_DAEMON}.pid
+
+        start-stop-daemon --start --quiet \
+                --background \
+                --exec /sbin/${HV_DAEMON} \
+                --make-pidfile --pidfile ${PIDFILE} \
+                --
+        eend 0
+}
+
+stop()
+{
+        [ ! -d /sys/bus/vmbus ] && exit 0
+
+        ebegin "Stopping Hyper-V Daemon: ${HV_DAEMON}"
+
+        [ -n "${PIDFILE}" ] || PIDFILE=/var/run/${HV_DAEMON}.pid
+
+        start-stop-daemon --stop --quiet --pidfile ${PIDFILE}
+
+        eend $? "Failed to stop ${HV_DAEMON}"
+}

alpine/packages/hvtools/hv_get_dhcp_info

@@ -0,0 +1,30 @@
+#!/bin/bash
+
+# Adjusted for Alpine
+
+# This example script retrieves the DHCP state of a given interface.
+# In the interest of keeping the KVP daemon code free of distro specific
+# information; the kvp daemon code invokes this external script to gather
+# DHCP setting for the specific interface.
+#
+# Input: Name of the interface
+#
+# Output: The script prints the string "Enabled" to stdout to indicate
+#	that DHCP is enabled on the interface. If DHCP is not enabled,
+#	the script prints the string "Disabled" to stdout.
+#
+# Each Distro is expected to implement this script in a distro specific
+# fashion. For instance on Distros that ship with Network Manager enabled,
+# this script can be based on the Network Manager APIs for retrieving DHCP
+# information.
+
+if_file="/etc/network/interfaces"
+
+dhcp=$(grep "$1.*dhcp" $if_file 2>/dev/null)
+
+if [ "$dhcp" != "" ];
+then
+echo "Enabled"
+else
+echo "Disabled"
+fi

alpine/packages/hvtools/hv_get_dns_info

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+# This example script parses /etc/resolv.conf to retrive DNS information.
+# In the interest of keeping the KVP daemon code free of distro specific
+# information; the kvp daemon code invokes this external script to gather
+# DNS information.
+# This script is expected to print the nameserver values to stdout.
+# Each Distro is expected to implement this script in a distro specific
+# fashion. For instance on Distros that ship with Network Manager enabled,
+# this script can be based on the Network Manager APIs for retrieving DNS
+# entries.
+
+cat /etc/resolv.conf 2>/dev/null | awk '/^nameserver/ { print $2 }'

alpine/packages/hvtools/hv_set_ifconfig

@@ -0,0 +1,90 @@
+#!/bin/bash
+
+# This example script activates an interface based on the specified
+# configuration.
+#
+# In the interest of keeping the KVP daemon code free of distro specific
+# information; the kvp daemon code invokes this external script to configure
+# the interface.
+#
+# The only argument to this script is the configuration file that is to
+# be used to configure the interface.
+#
+# Each Distro is expected to implement this script in a distro specific
+# fashion. For instance on Distros that ship with Network Manager enabled,
+# this script can be based on the Network Manager APIs for configuring the
+# interface.
+#
+# This example script is based on a RHEL environment.
+#
+# Here is the format of the ip configuration file:
+#
+# HWADDR=macaddr
+# DEVICE=interface name
+# BOOTPROTO=<protocol> (where <protocol> is "dhcp" if DHCP is configured
+#                       or "none" if no boot-time protocol should be used)
+#
+# IPADDR0=ipaddr1
+# IPADDR1=ipaddr2
+# IPADDRx=ipaddry (where y = x + 1)
+#
+# NETMASK0=netmask1
+# NETMASKx=netmasky (where y = x + 1)
+#
+# GATEWAY=ipaddr1
+# GATEWAYx=ipaddry (where y = x + 1)
+#
+# DNSx=ipaddrx (where first DNS address is tagged as DNS1 etc)
+#
+# IPV6 addresses will be tagged as IPV6ADDR, IPV6 gateway will be
+# tagged as IPV6_DEFAULTGW and IPV6 NETMASK will be tagged as
+# IPV6NETMASK.
+#
+# The host can specify multiple ipv4 and ipv6 addresses to be
+# configured for the interface. Furthermore, the configuration
+# needs to be persistent. A subsequent GET call on the interface
+# is expected to return the configuration that is set via the SET
+# call.
+#
+
+
+##
+## XXX This is really hacky. We just whack the existing
+## /etc/network/interfaces and also only configure IPv4. This will
+## break with multiple network interfaces etc.
+##
+
+
+# Stash away a copy of the config we got
+cp $1 /etc/network/hv_config
+
+# This is where we write the configuration
+outf=/etc/network/interfaces
+
+# Source it
+. $1
+
+# Down the interface
+ifdown $DEVICE
+
+# create a new interfaces file
+echo "auto lo" > $outf
+echo "iface lo inet loopback" >> $outf
+echo "" >> outf
+echo "auto $DEVICE" >> $outf
+
+if [  "$BOOTPROTO" = "dhcp" ]; then
+    echo "iface $DEVICE inet dhcp" >> $outf
+else
+    echo "iface $DEVICE inet static" >> $outf
+    echo "    address $IPADDR0" >> outf
+    echo "    netmask $NETMASK0" >> outf
+    echo "    gateway $GATEWAY" >> outf
+fi
+
+echo "    nameserver $DNS0" >> outf
+
+echo "    hwaddress ether $HWADDR" >> outf
+
+# Up the interface
+ifup $DEVICE

alpine/packages/hvtools/src/Makefile

@@ -0,0 +1,13 @@
+# Makefile for Hyper-V tools
+
+CC = $(CROSS_COMPILE)gcc
+PTHREAD_LIBS = -lpthread
+WARNINGS = -Wall -Wextra
+CFLAGS = $(WARNINGS) -g $(PTHREAD_LIBS) $(shell getconf LFS_CFLAGS)
+
+all: hv_kvp_daemon hv_vss_daemon hv_fcopy_daemon
+%: %.c
+	$(CC) $(CFLAGS) -o $@ $^
+
+clean:
+	$(RM) hv_kvp_daemon hv_vss_daemon hv_fcopy_daemon

alpine/packages/hvtools/src/hv_fcopy_daemon.c

@@ -0,0 +1,221 @@
+/*
+ * An implementation of host to guest copy functionality for Linux.
+ *
+ * Copyright (C) 2014, Microsoft, Inc.
+ *
+ * Author : K. Y. Srinivasan <kys@microsoft.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ */
+
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/poll.h>
+#include <linux/types.h>
+#include <linux/kdev_t.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <ctype.h>
+#include <errno.h>
+#include <linux/hyperv.h>
+#include <syslog.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <getopt.h>
+
+static int target_fd;
+static char target_fname[W_MAX_PATH];
+
+static int hv_start_fcopy(struct hv_start_fcopy *smsg)
+{
+	int error = HV_E_FAIL;
+	char *q, *p;
+
+	p = (char *)smsg->path_name;
+	snprintf(target_fname, sizeof(target_fname), "%s/%s",
+		 (char *)smsg->path_name, (char *)smsg->file_name);
+
+	syslog(LOG_INFO, "Target file name: %s", target_fname);
+	/*
+	 * Check to see if the path is already in place; if not,
+	 * create if required.
+	 */
+	while ((q = strchr(p, '/')) != NULL) {
+		if (q == p) {
+			p++;
+			continue;
+		}
+		*q = '\0';
+		if (access((char *)smsg->path_name, F_OK)) {
+			if (smsg->copy_flags & CREATE_PATH) {
+				if (mkdir((char *)smsg->path_name, 0755)) {
+					syslog(LOG_ERR, "Failed to create %s",
+						(char *)smsg->path_name);
+					goto done;
+				}
+			} else {
+				syslog(LOG_ERR, "Invalid path: %s",
+					(char *)smsg->path_name);
+				goto done;
+			}
+		}
+		p = q + 1;
+		*q = '/';
+	}
+
+	if (!access(target_fname, F_OK)) {
+		syslog(LOG_INFO, "File: %s exists", target_fname);
+		if (!(smsg->copy_flags & OVER_WRITE)) {
+			error = HV_ERROR_ALREADY_EXISTS;
+			goto done;
+		}
+	}
+
+	target_fd = open(target_fname,
+			 O_RDWR | O_CREAT | O_TRUNC | O_CLOEXEC, 0744);
+	if (target_fd == -1) {
+		syslog(LOG_INFO, "Open Failed: %s", strerror(errno));
+		goto done;
+	}
+
+	error = 0;
+done:
+	return error;
+}
+
+static int hv_copy_data(struct hv_do_fcopy *cpmsg)
+{
+	ssize_t bytes_written;
+
+	bytes_written = pwrite(target_fd, cpmsg->data, cpmsg->size,
+				cpmsg->offset);
+
+	if (bytes_written != cpmsg->size)
+		return HV_E_FAIL;
+
+	return 0;
+}
+
+static int hv_copy_finished(void)
+{
+	close(target_fd);
+	return 0;
+}
+static int hv_copy_cancel(void)
+{
+	close(target_fd);
+	unlink(target_fname);
+	return 0;
+
+}
+
+void print_usage(char *argv[])
+{
+	fprintf(stderr, "Usage: %s [options]\n"
+		"Options are:\n"
+		"  -n, --no-daemon        stay in foreground, don't daemonize\n"
+		"  -h, --help             print this help\n", argv[0]);
+}
+
+int main(int argc, char *argv[])
+{
+	int fcopy_fd, len;
+	int error;
+	int daemonize = 1, long_index = 0, opt;
+	int version = FCOPY_CURRENT_VERSION;
+	char *buffer[4096 * 2];
+	struct hv_fcopy_hdr *in_msg;
+
+	static struct option long_options[] = {
+		{"help",	no_argument,	   0,  'h' },
+		{"no-daemon",	no_argument,	   0,  'n' },
+		{0,		0,		   0,  0   }
+	};
+
+	while ((opt = getopt_long(argc, argv, "hn", long_options,
+				  &long_index)) != -1) {
+		switch (opt) {
+		case 'n':
+			daemonize = 0;
+			break;
+		case 'h':
+		default:
+			print_usage(argv);
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	if (daemonize && daemon(1, 0)) {
+		syslog(LOG_ERR, "daemon() failed; error: %s", strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	openlog("HV_FCOPY", 0, LOG_USER);
+	syslog(LOG_INFO, "HV_FCOPY starting; pid is:%d", getpid());
+
+	fcopy_fd = open("/dev/vmbus/hv_fcopy", O_RDWR);
+
+	if (fcopy_fd < 0) {
+		syslog(LOG_ERR, "open /dev/vmbus/hv_fcopy failed; error: %d %s",
+			errno, strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	/*
+	 * Register with the kernel.
+	 */
+	if ((write(fcopy_fd, &version, sizeof(int))) != sizeof(int)) {
+		syslog(LOG_ERR, "Registration failed: %s", strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	while (1) {
+		/*
+		 * In this loop we process fcopy messages after the
+		 * handshake is complete.
+		 */
+		len = pread(fcopy_fd, buffer, (4096 * 2), 0);
+		if (len < 0) {
+			syslog(LOG_ERR, "pread failed: %s", strerror(errno));
+			exit(EXIT_FAILURE);
+		}
+		in_msg = (struct hv_fcopy_hdr *)buffer;
+
+		switch (in_msg->operation) {
+		case START_FILE_COPY:
+			error = hv_start_fcopy((struct hv_start_fcopy *)in_msg);
+			break;
+		case WRITE_TO_FILE:
+			error = hv_copy_data((struct hv_do_fcopy *)in_msg);
+			break;
+		case COMPLETE_FCOPY:
+			error = hv_copy_finished();
+			break;
+		case CANCEL_FCOPY:
+			error = hv_copy_cancel();
+			break;
+
+		default:
+			syslog(LOG_ERR, "Unknown operation: %d",
+				in_msg->operation);
+
+		}
+
+		if (pwrite(fcopy_fd, &error, sizeof(int), 0) != sizeof(int)) {
+			syslog(LOG_ERR, "pwrite failed: %s", strerror(errno));
+			exit(EXIT_FAILURE);
+		}
+	}
+}

alpine/packages/hvtools/src/hv_get_dhcp_info.sh

@@ -0,0 +1,28 @@
+#!/bin/bash
+
+# This example script retrieves the DHCP state of a given interface.
+# In the interest of keeping the KVP daemon code free of distro specific
+# information; the kvp daemon code invokes this external script to gather
+# DHCP setting for the specific interface.
+#
+# Input: Name of the interface
+#
+# Output: The script prints the string "Enabled" to stdout to indicate
+#	that DHCP is enabled on the interface. If DHCP is not enabled,
+#	the script prints the string "Disabled" to stdout.
+#
+# Each Distro is expected to implement this script in a distro specific
+# fashion. For instance on Distros that ship with Network Manager enabled,
+# this script can be based on the Network Manager APIs for retrieving DHCP
+# information.
+
+if_file="/etc/sysconfig/network-scripts/ifcfg-"$1
+
+dhcp=$(grep "dhcp" $if_file 2>/dev/null)
+
+if [ "$dhcp" != "" ];
+then
+echo "Enabled"
+else
+echo "Disabled"
+fi

alpine/packages/hvtools/src/hv_get_dns_info.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+# This example script parses /etc/resolv.conf to retrive DNS information.
+# In the interest of keeping the KVP daemon code free of distro specific
+# information; the kvp daemon code invokes this external script to gather
+# DNS information.
+# This script is expected to print the nameserver values to stdout.
+# Each Distro is expected to implement this script in a distro specific
+# fashion. For instance on Distros that ship with Network Manager enabled,
+# this script can be based on the Network Manager APIs for retrieving DNS
+# entries.
+
+cat /etc/resolv.conf 2>/dev/null | awk '/^nameserver/ { print $2 }'

alpine/packages/hvtools/src/hv_set_ifconfig.sh

@@ -0,0 +1,64 @@
+#!/bin/bash
+
+# This example script activates an interface based on the specified
+# configuration.
+#
+# In the interest of keeping the KVP daemon code free of distro specific
+# information; the kvp daemon code invokes this external script to configure
+# the interface.
+#
+# The only argument to this script is the configuration file that is to
+# be used to configure the interface.
+#
+# Each Distro is expected to implement this script in a distro specific
+# fashion. For instance on Distros that ship with Network Manager enabled,
+# this script can be based on the Network Manager APIs for configuring the
+# interface.
+#
+# This example script is based on a RHEL environment.
+#
+# Here is the format of the ip configuration file:
+#
+# HWADDR=macaddr
+# DEVICE=interface name
+# BOOTPROTO=<protocol> (where <protocol> is "dhcp" if DHCP is configured
+#                       or "none" if no boot-time protocol should be used)
+#
+# IPADDR0=ipaddr1
+# IPADDR1=ipaddr2
+# IPADDRx=ipaddry (where y = x + 1)
+#
+# NETMASK0=netmask1
+# NETMASKx=netmasky (where y = x + 1)
+#
+# GATEWAY=ipaddr1
+# GATEWAYx=ipaddry (where y = x + 1)
+#
+# DNSx=ipaddrx (where first DNS address is tagged as DNS1 etc)
+#
+# IPV6 addresses will be tagged as IPV6ADDR, IPV6 gateway will be
+# tagged as IPV6_DEFAULTGW and IPV6 NETMASK will be tagged as
+# IPV6NETMASK.
+#
+# The host can specify multiple ipv4 and ipv6 addresses to be
+# configured for the interface. Furthermore, the configuration
+# needs to be persistent. A subsequent GET call on the interface
+# is expected to return the configuration that is set via the SET
+# call.
+#
+
+
+
+echo "IPV6INIT=yes" >> $1
+echo "NM_CONTROLLED=no" >> $1
+echo "PEERDNS=yes" >> $1
+echo "ONBOOT=yes" >> $1
+
+
+cp $1 /etc/sysconfig/network-scripts/
+
+
+interface=$(echo $1 | awk -F - '{ print $2 }')
+
+/sbin/ifdown $interface 2>/dev/null
+/sbin/ifup $interface 2>/dev/null

alpine/packages/hvtools/src/hv_vss_daemon.c

@@ -0,0 +1,342 @@
+/*
+ * An implementation of the host initiated guest snapshot for Hyper-V.
+ *
+ *
+ * Copyright (C) 2013, Microsoft, Inc.
+ * Author : K. Y. Srinivasan <kys@microsoft.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ *
+ */
+
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/poll.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <mntent.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <ctype.h>
+#include <errno.h>
+#include <arpa/inet.h>
+#include <linux/fs.h>
+#include <linux/connector.h>
+#include <linux/hyperv.h>
+#include <linux/netlink.h>
+#include <syslog.h>
+#include <getopt.h>
+
+static struct sockaddr_nl addr;
+
+#ifndef SOL_NETLINK
+#define SOL_NETLINK 270
+#endif
+
+
+/* Don't use syslog() in the function since that can cause write to disk */
+static int vss_do_freeze(char *dir, unsigned int cmd)
+{
+	int ret, fd = open(dir, O_RDONLY);
+
+	if (fd < 0)
+		return 1;
+
+	ret = ioctl(fd, cmd, 0);
+
+	/*
+	 * If a partition is mounted more than once, only the first
+	 * FREEZE/THAW can succeed and the later ones will get
+	 * EBUSY/EINVAL respectively: there could be 2 cases:
+	 * 1) a user may mount the same partition to differnt directories
+	 *  by mistake or on purpose;
+	 * 2) The subvolume of btrfs appears to have the same partition
+	 * mounted more than once.
+	 */
+	if (ret) {
+		if ((cmd == FIFREEZE && errno == EBUSY) ||
+		    (cmd == FITHAW && errno == EINVAL)) {
+			close(fd);
+			return 0;
+		}
+	}
+
+	close(fd);
+	return !!ret;
+}
+
+static int vss_operate(int operation)
+{
+	char match[] = "/dev/";
+	FILE *mounts;
+	struct mntent *ent;
+	char errdir[1024] = {0};
+	unsigned int cmd;
+	int error = 0, root_seen = 0, save_errno = 0;
+
+	switch (operation) {
+	case VSS_OP_FREEZE:
+		cmd = FIFREEZE;
+		break;
+	case VSS_OP_THAW:
+		cmd = FITHAW;
+		break;
+	default:
+		return -1;
+	}
+
+	mounts = setmntent("/proc/mounts", "r");
+	if (mounts == NULL)
+		return -1;
+
+	while ((ent = getmntent(mounts))) {
+		if (strncmp(ent->mnt_fsname, match, strlen(match)))
+			continue;
+		if (hasmntopt(ent, MNTOPT_RO) != NULL)
+			continue;
+		if (strcmp(ent->mnt_type, "vfat") == 0)
+			continue;
+		if (strcmp(ent->mnt_dir, "/") == 0) {
+			root_seen = 1;
+			continue;
+		}
+		error |= vss_do_freeze(ent->mnt_dir, cmd);
+		if (error && operation == VSS_OP_FREEZE)
+			goto err;
+	}
+
+	endmntent(mounts);
+
+	if (root_seen) {
+		error |= vss_do_freeze("/", cmd);
+		if (error && operation == VSS_OP_FREEZE)
+			goto err;
+	}
+
+	goto out;
+err:
+	save_errno = errno;
+	if (ent) {
+		strncpy(errdir, ent->mnt_dir, sizeof(errdir)-1);
+		endmntent(mounts);
+	}
+	vss_operate(VSS_OP_THAW);
+	/* Call syslog after we thaw all filesystems */
+	if (ent)
+		syslog(LOG_ERR, "FREEZE of %s failed; error:%d %s",
+		       errdir, save_errno, strerror(save_errno));
+	else
+		syslog(LOG_ERR, "FREEZE of / failed; error:%d %s", save_errno,
+		       strerror(save_errno));
+out:
+	return error;
+}
+
+static int netlink_send(int fd, struct cn_msg *msg)
+{
+	struct nlmsghdr nlh = { .nlmsg_type = NLMSG_DONE };
+	unsigned int size;
+	struct msghdr message;
+	struct iovec iov[2];
+
+	size = sizeof(struct cn_msg) + msg->len;
+
+	nlh.nlmsg_pid = getpid();
+	nlh.nlmsg_len = NLMSG_LENGTH(size);
+
+	iov[0].iov_base = &nlh;
+	iov[0].iov_len = sizeof(nlh);
+
+	iov[1].iov_base = msg;
+	iov[1].iov_len = size;
+
+	memset(&message, 0, sizeof(message));
+	message.msg_name = &addr;
+	message.msg_namelen = sizeof(addr);
+	message.msg_iov = iov;
+	message.msg_iovlen = 2;
+
+	return sendmsg(fd, &message, 0);
+}
+
+void print_usage(char *argv[])
+{
+	fprintf(stderr, "Usage: %s [options]\n"
+		"Options are:\n"
+		"  -n, --no-daemon        stay in foreground, don't daemonize\n"
+		"  -h, --help             print this help\n", argv[0]);
+}
+
+int main(int argc, char *argv[])
+{
+	int fd, len, nl_group;
+	int error;
+	struct cn_msg *message;
+	struct pollfd pfd;
+	struct nlmsghdr *incoming_msg;
+	struct cn_msg	*incoming_cn_msg;
+	int	op;
+	struct hv_vss_msg *vss_msg;
+	char *vss_recv_buffer;
+	size_t vss_recv_buffer_len;
+	int daemonize = 1, long_index = 0, opt;
+
+	static struct option long_options[] = {
+		{"help",	no_argument,	   0,  'h' },
+		{"no-daemon",	no_argument,	   0,  'n' },
+		{0,		0,		   0,  0   }
+	};
+
+	while ((opt = getopt_long(argc, argv, "hn", long_options,
+				  &long_index)) != -1) {
+		switch (opt) {
+		case 'n':
+			daemonize = 0;
+			break;
+		case 'h':
+		default:
+			print_usage(argv);
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	if (daemonize && daemon(1, 0))
+		return 1;
+
+	openlog("Hyper-V VSS", 0, LOG_USER);
+	syslog(LOG_INFO, "VSS starting; pid is:%d", getpid());
+
+	vss_recv_buffer_len = NLMSG_LENGTH(0) + sizeof(struct cn_msg) + sizeof(struct hv_vss_msg);
+	vss_recv_buffer = calloc(1, vss_recv_buffer_len);
+	if (!vss_recv_buffer) {
+		syslog(LOG_ERR, "Failed to allocate netlink buffers");
+		exit(EXIT_FAILURE);
+	}
+
+	fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR);
+	if (fd < 0) {
+		syslog(LOG_ERR, "netlink socket creation failed; error:%d %s",
+				errno, strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+	addr.nl_family = AF_NETLINK;
+	addr.nl_pad = 0;
+	addr.nl_pid = 0;
+	addr.nl_groups = 0;
+
+
+	error = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
+	if (error < 0) {
+		syslog(LOG_ERR, "bind failed; error:%d %s", errno, strerror(errno));
+		close(fd);
+		exit(EXIT_FAILURE);
+	}
+	nl_group = CN_VSS_IDX;
+	if (setsockopt(fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &nl_group, sizeof(nl_group)) < 0) {
+		syslog(LOG_ERR, "setsockopt failed; error:%d %s", errno, strerror(errno));
+		close(fd);
+		exit(EXIT_FAILURE);
+	}
+	/*
+	 * Register ourselves with the kernel.
+	 */
+	message = (struct cn_msg *)vss_recv_buffer;
+	message->id.idx = CN_VSS_IDX;
+	message->id.val = CN_VSS_VAL;
+	message->ack = 0;
+	vss_msg = (struct hv_vss_msg *)message->data;
+	vss_msg->vss_hdr.operation = VSS_OP_REGISTER;
+
+	message->len = sizeof(struct hv_vss_msg);
+
+	len = netlink_send(fd, message);
+	if (len < 0) {
+		syslog(LOG_ERR, "netlink_send failed; error:%d %s", errno, strerror(errno));
+		close(fd);
+		exit(EXIT_FAILURE);
+	}
+
+	pfd.fd = fd;
+
+	while (1) {
+		struct sockaddr *addr_p = (struct sockaddr *) &addr;
+		socklen_t addr_l = sizeof(addr);
+		pfd.events = POLLIN;
+		pfd.revents = 0;
+
+		if (poll(&pfd, 1, -1) < 0) {
+			syslog(LOG_ERR, "poll failed; error:%d %s", errno, strerror(errno));
+			if (errno == EINVAL) {
+				close(fd);
+				exit(EXIT_FAILURE);
+			}
+			else
+				continue;
+		}
+
+		len = recvfrom(fd, vss_recv_buffer, vss_recv_buffer_len, 0,
+				addr_p, &addr_l);
+
+		if (len < 0) {
+			syslog(LOG_ERR, "recvfrom failed; pid:%u error:%d %s",
+					addr.nl_pid, errno, strerror(errno));
+			close(fd);
+			return -1;
+		}
+
+		if (addr.nl_pid) {
+			syslog(LOG_WARNING,
+				"Received packet from untrusted pid:%u",
+				addr.nl_pid);
+			continue;
+		}
+
+		incoming_msg = (struct nlmsghdr *)vss_recv_buffer;
+
+		if (incoming_msg->nlmsg_type != NLMSG_DONE)
+			continue;
+
+		incoming_cn_msg = (struct cn_msg *)NLMSG_DATA(incoming_msg);
+		vss_msg = (struct hv_vss_msg *)incoming_cn_msg->data;
+		op = vss_msg->vss_hdr.operation;
+		error =  HV_S_OK;
+
+		switch (op) {
+		case VSS_OP_FREEZE:
+		case VSS_OP_THAW:
+			error = vss_operate(op);
+			syslog(LOG_INFO, "VSS: op=%s: %s\n",
+				op == VSS_OP_FREEZE ? "FREEZE" : "THAW",
+				error ? "failed" : "succeeded");
+
+			if (error) {
+				error = HV_E_FAIL;
+				syslog(LOG_ERR, "op=%d failed!", op);
+				syslog(LOG_ERR, "report it with these files:");
+				syslog(LOG_ERR, "/etc/fstab and /proc/mounts");
+			}
+			break;
+		default:
+			syslog(LOG_ERR, "Illegal op:%d\n", op);
+		}
+		vss_msg->error = error;
+		len = netlink_send(fd, incoming_cn_msg);
+		if (len < 0) {
+			syslog(LOG_ERR, "net_link send failed; error:%d %s",
+					errno, strerror(errno));
+			exit(EXIT_FAILURE);
+		}
+	}
+
+}

alpine/packages/hvtools/src/lsvmbus

@@ -0,0 +1,101 @@
+#!/usr/bin/env python
+
+import os
+from optparse import OptionParser
+
+parser = OptionParser()
+parser.add_option("-v", "--verbose", dest="verbose",
+		   help="print verbose messages. Try -vv, -vvv for \
+			more verbose messages", action="count")
+
+(options, args) = parser.parse_args()
+
+verbose = 0
+if options.verbose is not None:
+	verbose = options.verbose
+
+vmbus_sys_path = '/sys/bus/vmbus/devices'
+if not os.path.isdir(vmbus_sys_path):
+	print "%s doesn't exist: exiting..." % vmbus_sys_path
+	exit(-1)
+
+vmbus_dev_dict = {
+	'{0e0b6031-5213-4934-818b-38d90ced39db}' : '[Operating system shutdown]',
+	'{9527e630-d0ae-497b-adce-e80ab0175caf}' : '[Time Synchronization]',
+	'{57164f39-9115-4e78-ab55-382f3bd5422d}' : '[Heartbeat]',
+	'{a9a0f4e7-5a45-4d96-b827-8a841e8c03e6}' : '[Data Exchange]',
+	'{35fa2e29-ea23-4236-96ae-3a6ebacba440}' : '[Backup (volume checkpoint)]',
+	'{34d14be3-dee4-41c8-9ae7-6b174977c192}' : '[Guest services]',
+	'{525074dc-8985-46e2-8057-a307dc18a502}' : '[Dynamic Memory]',
+	'{cfa8b69e-5b4a-4cc0-b98b-8ba1a1f3f95a}' : 'Synthetic mouse',
+	'{f912ad6d-2b17-48ea-bd65-f927a61c7684}' : 'Synthetic keyboard',
+	'{da0a7802-e377-4aac-8e77-0558eb1073f8}' : 'Synthetic framebuffer adapter',
+	'{f8615163-df3e-46c5-913f-f2d2f965ed0e}' : 'Synthetic network adapter',
+	'{32412632-86cb-44a2-9b5c-50d1417354f5}' : 'Synthetic IDE Controller',
+	'{ba6163d9-04a1-4d29-b605-72e2ffb1dc7f}' : 'Synthetic SCSI Controller',
+	'{2f9bcc4a-0069-4af3-b76b-6fd0be528cda}' : 'Synthetic fiber channel adapter',
+	'{8c2eaf3d-32a7-4b09-ab99-bd1f1c86b501}' : 'Synthetic RDMA adapter',
+	'{276aacf4-ac15-426c-98dd-7521ad3f01fe}' : '[Reserved system device]',
+	'{f8e65716-3cb3-4a06-9a60-1889c5cccab5}' : '[Reserved system device]',
+	'{3375baf4-9e15-4b30-b765-67acb10d607b}' : '[Reserved system device]',
+}
+
+def get_vmbus_dev_attr(dev_name, attr):
+	try:
+		f = open('%s/%s/%s' % (vmbus_sys_path, dev_name, attr), 'r')
+		lines = f.readlines()
+		f.close()
+	except IOError:
+		lines = []
+
+	return lines
+
+class VMBus_Dev:
+	pass
+
+
+vmbus_dev_list = []
+
+for f in os.listdir(vmbus_sys_path):
+	vmbus_id = get_vmbus_dev_attr(f, 'id')[0].strip()
+	class_id = get_vmbus_dev_attr(f, 'class_id')[0].strip()
+	device_id = get_vmbus_dev_attr(f, 'device_id')[0].strip()
+	dev_desc = vmbus_dev_dict.get(class_id, 'Unknown')
+
+	chn_vp_mapping = get_vmbus_dev_attr(f, 'channel_vp_mapping')
+	chn_vp_mapping = [c.strip() for c in chn_vp_mapping]
+	chn_vp_mapping = sorted(chn_vp_mapping,
+		key = lambda c : int(c.split(':')[0]))
+
+	chn_vp_mapping = ['\tRel_ID=%s, target_cpu=%s' %
+				(c.split(':')[0], c.split(':')[1])
+					for c in chn_vp_mapping]
+	d = VMBus_Dev()
+	d.sysfs_path = '%s/%s' % (vmbus_sys_path, f)
+	d.vmbus_id = vmbus_id
+	d.class_id = class_id
+	d.device_id = device_id
+	d.dev_desc = dev_desc
+	d.chn_vp_mapping = '\n'.join(chn_vp_mapping)
+	if d.chn_vp_mapping:
+		d.chn_vp_mapping += '\n'
+
+	vmbus_dev_list.append(d)
+
+
+vmbus_dev_list  = sorted(vmbus_dev_list, key = lambda d : int(d.vmbus_id))
+
+format0 = '%2s: %s'
+format1 = '%2s: Class_ID = %s - %s\n%s'
+format2 = '%2s: Class_ID = %s - %s\n\tDevice_ID = %s\n\tSysfs path: %s\n%s'
+
+for d in vmbus_dev_list:
+	if verbose == 0:
+		print ('VMBUS ID ' + format0) % (d.vmbus_id, d.dev_desc)
+	elif verbose == 1:
+		print ('VMBUS ID ' + format1) %	\
+			(d.vmbus_id, d.class_id, d.dev_desc, d.chn_vp_mapping)
+	else:
+		print ('VMBUS ID ' + format2) % \
+			(d.vmbus_id, d.class_id, d.dev_desc, \
+			d.device_id, d.sysfs_path, d.chn_vp_mapping)