Add libxenlight driver

Add a new xen driver based on libxenlight [1], which is the primary
toolstack starting with Xen 4.1.0.  The driver is stateful and runs
privileged only.

Like the existing xen-unified driver, the libxenlight driver is
accessed with xen:// URI.  Driver selection is based on the status
of xend.  If xend is running, the libxenlight driver will not load
and xen:// connections are handled by xen-unified.  If xend is not
running *and* the libxenlight driver is available, xen://
connections are deferred to the libxenlight driver.

V6:
 - Address several code style issues noted by Daniel Veillard
 - Make drive work with xen:/// URI
 - Hold domain object reference while domain is injected in
   libvirt event loop.  Race found and fixed by Markus Groß.

V5:
 - Ensure events are unregistered when domain private data
   is destroyed.  Discovered and fixed by Markus Groß.

V4:
 - Handle restart of libvirtd, reconnecting to previously
   started domains
 - Rebased to current master
 - Tested against Xen 4.1 RC7-pre (c/s 22961:c5d121fd35c0)

V3:
  - Reserve vnc port within driver when autoport=yes

V2:
  - Update to Xen 4.1 RC6-pre (c/s 22940:5a4710640f81)
  - Rebased to current master
  - Plug memory leaks found by Stefano Stabellini and valgrind
  - Handle SHUTDOWN_crash domain death event

[1] http://lists.xensource.com/archives/html/xen-devel/2009-11/msg00436.html

cfg.mk

@@ -403,6 +403,7 @@ msg_gen_function += virXenStoreError
 msg_gen_function += virXendError
 msg_gen_function += vmwareError
 msg_gen_function += xenapiSessionErrorHandler
+msg_gen_function += libxlError
 msg_gen_function += xenUnifiedError
 msg_gen_function += xenXMError
 msg_gen_function += VIR_ERROR

configure.ac

@@ -263,6 +263,8 @@ AC_ARG_WITH([phyp],
   AC_HELP_STRING([--with-phyp], [add PHYP support @<:@default=check@:>@]),[],[with_phyp=check])
 AC_ARG_WITH([xenapi],
   AC_HELP_STRING([--with-xenapi], [add XenAPI support @<:@default=check@:>@]),[],[with_xenapi=check])
+AC_ARG_WITH([libxl],
+  AC_HELP_STRING([--with-libxl], [add libxenlight support @<:@default=check@:>@]),[],[with_libxl=check])
 AC_ARG_WITH([vbox],
   AC_HELP_STRING([--with-vbox=@<:@PFX@:>@],
                  [VirtualBox XPCOMC location @<:@default=yes@:>@]),[],
@@ -497,6 +499,46 @@ fi
 AC_SUBST([LIBXENSERVER_CFLAGS])
 AC_SUBST([LIBXENSERVER_LIBS])
 
+old_LIBS="$LIBS"
+old_CFLAGS="$CFLAGS"
+LIBXL_LIBS=""
+LIBXL_CFLAGS=""
+dnl search for libxl, aka libxenlight
+fail=0
+if test "$with_libxl" != "no" ; then
+    if test "$with_libxl" != "yes" && test "$with_libxl" != "check" ; then
+        LIBXL_CFLAGS="-I$with_libxl/include"
+        LIBXL_LIBS="-L$with_libxl"
+    fi
+    CFLAGS="$CFLAGS $LIBXL_CFLAGS"
+    LIBS="$LIBS $LIBXL_LIBS"
+    AC_CHECK_LIB([xenlight], [libxl_ctx_init], [
+        with_libxl=yes
+        LIBXL_LIBS="$LIBXL_LIBS -lxenlight -lxenstore -lxenctrl -lxenguest -luuid -lutil -lblktapctl"
+    ],[
+        if test "$with_libxl" = "yes"; then
+            fail=1
+        fi
+        with_libxl=no
+    ],[
+        -lxenstore -lxenctrl -lxenguest -luuid -lutil -lblktapctl
+    ])
+fi
+
+LIBS="$old_LIBS"
+CFLAGS="$old_CFLAGS"
+
+if test $fail = 1; then
+    AC_MSG_ERROR([You must install the libxl Library to compile libxenlight driver with -lxl])
+fi
+
+if test "$with_libxl" = "yes"; then
+    AC_DEFINE_UNQUOTED([WITH_LIBXL], 1, [whether libxenlight driver is enabled])
+fi
+AM_CONDITIONAL([WITH_LIBXL], [test "$with_libxl" = "yes"])
+
+AC_SUBST([LIBXL_CFLAGS])
+AC_SUBST([LIBXL_LIBS])
 
 old_LIBS="$LIBS"
 old_CFLAGS="$CFLAGS"
@@ -2370,6 +2412,7 @@ AC_MSG_NOTICE([  OpenVZ: $with_openvz])
 AC_MSG_NOTICE([  VMware: $with_vmware])
 AC_MSG_NOTICE([    VBox: $with_vbox])
 AC_MSG_NOTICE([  XenAPI: $with_xenapi])
+AC_MSG_NOTICE([xenlight: $with_libxl])
 AC_MSG_NOTICE([     LXC: $with_lxc])
 AC_MSG_NOTICE([    PHYP: $with_phyp])
 AC_MSG_NOTICE([     ONE: $with_one])
@@ -2479,6 +2522,11 @@ AC_MSG_NOTICE([  xenapi: $LIBXENSERVER_CFLAGS $LIBXENSERVER_LIBS])
 else
 AC_MSG_NOTICE([  xenapi: no])
 fi
+if test "$with_libxl" = "yes" ; then
+AC_MSG_NOTICE([  libxenlight: $LIBXL_CFLAGS $LIBXL_LIBS])
+else
+AC_MSG_NOTICE([  libxenlight: no])
+fi
 if test "$with_hal" = "yes" ; then
 AC_MSG_NOTICE([     hal: $HAL_CFLAGS $HAL_LIBS])
 else

daemon/Makefile.am

@@ -106,6 +106,10 @@ if WITH_LXC
     libvirtd_LDADD += ../src/libvirt_driver_lxc.la
 endif
 
+if WITH_LIBXL
+    libvirtd_LDADD += ../src/libvirt_driver_libxl.la
+endif
+
 if WITH_UML
     libvirtd_LDADD += ../src/libvirt_driver_uml.la
 endif

daemon/libvirtd.c

@@ -81,6 +81,9 @@
 # ifdef WITH_LXC
 #  include "lxc/lxc_driver.h"
 # endif
+# ifdef WITH_LIBXL
+#  include "libxl/libxl_driver.h"
+# endif
 # ifdef WITH_UML
 #  include "uml/uml_driver.h"
 # endif
@@ -943,6 +946,9 @@ static struct qemud_server *qemudInitialize(void) {
 # ifdef WITH_NWFILTER
     nwfilterRegister();
 # endif
+# ifdef WITH_LIBXL
+    libxlRegister();
+# endif
 # ifdef WITH_QEMU
     qemuRegister();
 # endif

include/libvirt/virterror.h

@@ -80,6 +80,7 @@ typedef enum {
     VIR_FROM_STREAMS = 38,	/* Error from I/O streams */
     VIR_FROM_VMWARE = 39,	/* Error from VMware driver */
     VIR_FROM_EVENT = 40,       /* Error from event loop impl */
+    VIR_FROM_LIBXL = 41,	/* Error from libxenlight driver */
 } virErrorDomain;
 
 

libvirt.spec.in

@@ -45,6 +45,7 @@
 %define with_vbox          0%{!?_without_vbox:%{server_drivers}}
 %define with_uml           0%{!?_without_uml:%{server_drivers}}
 %define with_xenapi        0%{!?_without_xenapi:%{server_drivers}}
+%define with_libxl         0%{!?_without_libxl:%{server_drivers}}
 # XXX this shouldn't be here, but it mistakenly links into libvirtd
 %define with_one           0%{!?_without_one:%{server_drivers}}
 
@@ -96,7 +97,7 @@
 %endif
 
 # RHEL doesn't ship OpenVZ, VBox, UML, OpenNebula, PowerHypervisor,
-# VMWare, or libxenserver (xenapi)
+# VMWare, libxenserver (xenapi), or libxenlight (Xen 4.1 and newer)
 %if 0%{?rhel}
 %define with_openvz 0
 %define with_vbox 0
@@ -105,6 +106,7 @@
 %define with_phyp 0
 %define with_vmware 0
 %define with_xenapi 0
+%define with_libxl 0
 %endif
 
 # RHEL-5 has restricted QEMU to x86_64 only and is too old for LXC
@@ -493,6 +495,10 @@ of recent versions of Linux (and other OSes).
 %define _without_xenapi --without-xenapi
 %endif
 
+%if ! %{with_libxl}
+%define _without_libxl --without-libxl
+%endif
+
 %if ! %{with_sasl}
 %define _without_sasl --without-sasl
 %endif
@@ -872,6 +878,9 @@ fi
 %dir %attr(0700, root, root) %{_localstatedir}/log/libvirt/qemu/
 %dir %attr(0700, root, root) %{_localstatedir}/log/libvirt/lxc/
 %dir %attr(0700, root, root) %{_localstatedir}/log/libvirt/uml/
+%if %{with_libxl}
+%dir %attr(0700, root, root) %{_localstatedir}/log/libvirt/libxl/
+%endif
 
 %config(noreplace) %{_sysconfdir}/logrotate.d/libvirtd
 %if %{with_qemu}
@@ -912,6 +921,10 @@ fi
 %dir %{_localstatedir}/run/libvirt/uml/
 %dir %attr(0700, root, root) %{_localstatedir}/lib/libvirt/uml/
 %endif
+%if %{with_libxl}
+%dir %{_localstatedir}/run/libvirt/libxl/
+%dir %attr(0700, root, root) %{_localstatedir}/lib/libvirt/libxl/
+%endif
 %if %{with_network}
 %dir %{_localstatedir}/run/libvirt/network/
 %dir %attr(0700, root, root) %{_localstatedir}/lib/libvirt/network/

po/POTFILES.in

@@ -34,6 +34,8 @@ src/lxc/lxc_conf.c
 src/lxc/lxc_controller.c
 src/lxc/lxc_driver.c
 src/lxc/veth.c
+src/libxl/libxl_driver.c
+src/libxl/libxl_conf.c
 src/network/bridge_driver.c
 src/node_device/node_device_driver.c
 src/node_device/node_device_hal.c

src/Makefile.am

@@ -298,6 +298,10 @@ XENAPI_DRIVER_SOURCES =								\
 		xenapi/xenapi_driver_private.h					\
 		xenapi/xenapi_utils.c xenapi/xenapi_utils.h
 
+LIBXL_DRIVER_SOURCES =						\
+		libxl/libxl_conf.c libxl/libxl_conf.h		\
+		libxl/libxl_driver.c libxl/libxl_driver.h
+
 UML_DRIVER_SOURCES =						\
 		uml/uml_conf.c uml/uml_conf.h			\
 		uml/uml_driver.c uml/uml_driver.h
@@ -692,6 +696,25 @@ endif
 libvirt_driver_xenapi_la_SOURCES = $(XENAPI_DRIVER_SOURCES)
 endif
 
+if WITH_LIBXL
+if WITH_DRIVER_MODULES
+mod_LTLIBRARIES += libvirt_driver_libxl.la
+else
+noinst_LTLIBRARIES += libvirt_driver_libxl.la
+# Stateful, so linked to daemon instead
+#libvirt_la_BUILT_LIBADD += libvirt_driver_libxl.la
+endif
+libvirt_driver_libxl_la_CFLAGS = $(LIBXL_CFLAGS) \
+		-I@top_srcdir@/src/conf $(AM_CFLAGS)
+libvirt_driver_libxl_la_LDFLAGS = $(AM_LDFLAGS)
+libvirt_driver_libxl_la_LIBADD = $(LIBXL_LIBS)
+if WITH_DRIVER_MODULES
+libvirt_driver_libxl_la_LIBADD += ../gnulib/lib/libgnu.la
+libvirt_driver_libxl_la_LDFLAGS += -module -avoid-version
+endif
+libvirt_driver_libxl_la_SOURCES = $(LIBXL_DRIVER_SOURCES)
+endif
+
 if WITH_QEMU
 if WITH_DRIVER_MODULES
 mod_LTLIBRARIES += libvirt_driver_qemu.la
@@ -1005,6 +1028,7 @@ EXTRA_DIST +=							\
 		$(PHYP_DRIVER_SOURCES)				\
 		$(VBOX_DRIVER_SOURCES)				\
 		$(XENAPI_DRIVER_SOURCES)			\
+		$(LIBXL_DRIVER_SOURCES)			\
 		$(ESX_DRIVER_SOURCES)				\
 		$(ESX_DRIVER_EXTRA_DIST)			\
 		$(NETWORK_DRIVER_SOURCES)			\
@@ -1259,6 +1283,10 @@ if WITH_LXC
 	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/lib/libvirt/lxc"
 	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/run/libvirt/lxc"
 endif
+if WITH_LIBXL
+	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/lib/libvirt/libxl"
+	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/run/libvirt/libxl"
+endif
 if WITH_UML
 	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/lib/libvirt/uml"
 	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/run/libvirt/uml"
@@ -1296,6 +1324,10 @@ if WITH_LXC
 	rmdir "$(DESTDIR)$(localstatedir)/lib/libvirt/lxc" ||:
 	rmdir "$(DESTDIR)$(localstatedir)/run/libvirt/lxc" ||:
 endif
+if WITH_LIBXL
+	rmdir "$(DESTDIR)$(localstatedir)/lib/libvirt/libxl" ||:
+	rmdir "$(DESTDIR)$(localstatedir)/run/libvirt/libxl" ||:
+endif
 if WITH_UML
 	rmdir "$(DESTDIR)$(localstatedir)/lib/libvirt/uml" ||:
 	rmdir "$(DESTDIR)$(localstatedir)/run/libvirt/uml" ||:

src/driver.h

@@ -27,7 +27,8 @@ typedef enum {
     VIR_DRV_ESX = 10,
     VIR_DRV_PHYP = 11,
     VIR_DRV_XENAPI = 12,
-    VIR_DRV_VMWARE = 13
+    VIR_DRV_VMWARE = 13,
+    VIR_DRV_LIBXL = 14,
 } virDrvNo;
 
 

src/libvirt.c

@@ -912,6 +912,10 @@ virGetVersion(unsigned long *libVer, const char *type,
         if (STRCASEEQ(type, "LXC"))
             *typeVer = LIBVIR_VERSION_NUMBER;
 # endif
+# if WITH_LIBXL
+        if (STRCASEEQ(type, "xenlight"))
+            *typeVer = LIBVIR_VERSION_NUMBER;
+# endif
 # if WITH_PHYP
         if (STRCASEEQ(type, "phyp"))
             *typeVer = LIBVIR_VERSION_NUMBER;

src/libxl/libxl_conf.h

+/*---------------------------------------------------------------------------*/
+/*  Copyright (c) 2011 SUSE LINUX Products GmbH, Nuernberg, Germany.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
+ */
+/*---------------------------------------------------------------------------*/
+
+#ifndef LIBXL_CONF_H
+# define LIBXL_CONF_H
+
+# include <config.h>
+
+# include <libxl.h>
+
+# include "internal.h"
+# include "domain_conf.h"
+# include "capabilities.h"
+# include "configmake.h"
+# include "bitmap.h"
+
+
+# define LIBXL_VNC_PORT_MIN  5900
+# define LIBXL_VNC_PORT_MAX  65535
+
+# define LIBXL_CONFIG_DIR SYSCONFDIR "/libvirt/libxl"
+# define LIBXL_AUTOSTART_DIR LIBXL_CONFIG_DIR "/autostart"
+# define LIBXL_STATE_DIR LOCALSTATEDIR "/run/libvirt/libxl"
+# define LIBXL_LOG_DIR LOCALSTATEDIR "/log/libvirt/libxl"
+# define LIBXL_LIB_DIR LOCALSTATEDIR "/lib/libvirt/libxl"
+# define LIBXL_SAVE_DIR LIBXL_LIB_DIR "/save"
+
+
+typedef struct _libxlDriverPrivate libxlDriverPrivate;
+typedef libxlDriverPrivate *libxlDriverPrivatePtr;
+struct _libxlDriverPrivate {
+    virMutex lock;
+    virCapsPtr caps;
+    unsigned int version;
+
+    FILE *logger_file;
+    xentoollog_logger *logger;
+    /* libxl ctx for driver wide ops; getVersion, getNodeInfo, ... */
+    libxl_ctx ctx;
+
+    virBitmapPtr reservedVNCPorts;
+    virDomainObjList domains;
+
+    char *configDir;
+    char *autostartDir;
+    char *logDir;
+    char *stateDir;
+    char *libDir;
+    char *saveDir;
+};
+
+typedef struct _libxlDomainObjPrivate libxlDomainObjPrivate;
+typedef libxlDomainObjPrivate *libxlDomainObjPrivatePtr;
+struct _libxlDomainObjPrivate {
+    /* per domain libxl ctx */
+    libxl_ctx ctx;
+    libxl_waiter *dWaiter;
+    int waiterFD;
+    int eventHdl;
+};
+
+
+# define libxlError(code, ...)                                     \
+    virReportErrorHelper(NULL, VIR_FROM_LIBXL, code, __FILE__,     \
+                         __FUNCTION__, __LINE__, __VA_ARGS__)
+
+virCapsPtr
+libxlMakeCapabilities(libxl_ctx *ctx);
+
+int
+libxlBuildDomainConfig(libxlDriverPrivatePtr driver,
+                       virDomainDefPtr def, libxl_domain_config *d_config);
+
+
+#endif /* LIBXL_CONF_H */

src/libxl/libxl_driver.h

+/*---------------------------------------------------------------------------*/
+/*  Copyright (c) 2011 SUSE LINUX Products GmbH, Nuernberg, Germany.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
+ */
+/*---------------------------------------------------------------------------*/
+
+#ifndef LIBXL_DRIVER_H
+# define LIBXL_DRIVER_H
+
+# include <config.h>
+
+int libxlRegister(void);
+
+#endif /* LIBXL_DRIVER_H */

src/util/virterror.c

@@ -89,6 +89,9 @@ static const char *virErrorDomainName(virErrorDomain domain) {
         case VIR_FROM_XENAPI:
             dom = "XenAPI ";
             break;
+        case VIR_FROM_LIBXL:
+            dom = "xenlight ";
+            break;
         case VIR_FROM_XML:
             dom = "XML ";
             break;

src/xen/xen_driver.c

@@ -50,6 +50,7 @@
 #include "uuid.h"
 #include "fdstream.h"
 #include "files.h"
+#include "command.h"
 
 #define VIR_FROM_THIS VIR_FROM_XEN
 
@@ -229,6 +230,23 @@ xenUnifiedProbe (void)
     return 0;
 }
 
+#ifdef WITH_LIBXL
+static int
+xenUnifiedXendProbe (void)
+{
+    virCommandPtr cmd;
+    int status;
+    int ret = 0;
+
+    cmd = virCommandNewArgList("/usr/sbin/xend", "status", NULL);
+    if (virCommandRun(cmd, &status) == 0 && status == 0)
+        ret = 1;
+    virCommandFree(cmd);
+
+    return ret;
+}
+#endif
+
 static virDrvOpenStatus
 xenUnifiedOpen (virConnectPtr conn, virConnectAuthPtr auth, int flags)
 {
@@ -292,6 +310,13 @@ xenUnifiedOpen (virConnectPtr conn, virConnectAuthPtr auth, int flags)
         }
     }
 
+#ifdef WITH_LIBXL
+    /* Decline xen:// URI if xend is not running and libxenlight
+     * driver is potentially available. */
+    if (!xenUnifiedXendProbe())
+        return VIR_DRV_OPEN_DECLINED;
+#endif
+
     /* We now know the URI is definitely for this driver, so beyond
      * here, don't return DECLINED, always use ERROR */