implement managedsave in libvirt xen legacy driver

Implement the domainManagedSave, domainHasManagedSaveImage, and
domainManagedSaveRemove functions in the libvirt legacy xen driver.

domainHasManagedSaveImage check the managedsave image from filesystem
everytime. This is different from qemu and libxl driver. In qemu or
libxl driver, there is a hasManagesSave flag in virDomainObjPtr which
is not used in xen legacy driver. This flag could not add into xen
driver ptr either, because the driver ptr will be released at the end of
every libvirt api call. Meanwhile, AFAIK, xen store all the flags in
xen not in libvirt xen driver. There is no need to add this flag in xen.

Signed-off-by: Bamvor Jian Zhang <bjzhang@suse.com>

libvirt.spec.in

@@ -1719,6 +1719,9 @@ rm -f $RPM_BUILD_ROOT%{_sysconfdir}/sysctl.d/libvirtd
 %ghost %dir %{_localstatedir}/run/libvirt/libxl/
 %dir %attr(0700, root, root) %{_localstatedir}/lib/libvirt/libxl/
 %endif
+%if %{with_xen}
+%dir %attr(0700, root, root) %{_localstatedir}/lib/libvirt/xen/
+%endif
 %if %{with_network}
 %ghost %dir %{_localstatedir}/run/libvirt/network/
 %dir %attr(0700, root, root) %{_localstatedir}/lib/libvirt/network/

src/Makefile.am

@@ -1771,6 +1771,9 @@ if WITH_UML
 	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/lib/libvirt/uml"
 	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/run/libvirt/uml"
 endif
+if WITH_XEN
+	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/lib/libvirt/xen"
+endif
 if WITH_NETWORK
 	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/lib/libvirt/network"
 	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/lib/libvirt/dnsmasq"
@@ -1817,6 +1820,9 @@ if WITH_UML
 	rmdir "$(DESTDIR)$(localstatedir)/lib/libvirt/uml" ||:
 	rmdir "$(DESTDIR)$(localstatedir)/run/libvirt/uml" ||:
 endif
+if WITH_XEN
+	rmdir "$(DESTDIR)$(localstatedir)/lib/libvirt/xen" ||:
+endif
 if WITH_NETWORK
 	rm -f $(DESTDIR)$(sysconfdir)/libvirt/qemu/networks/autostart/default.xml
 	rm -f $(DESTDIR)$(sysconfdir)/libvirt/qemu/networks/default.xml

src/xen/xen_driver.c

@@ -65,8 +65,10 @@
 #include "command.h"
 #include "virnodesuspend.h"
 #include "nodeinfo.h"
+#include "configmake.h"
 
 #define VIR_FROM_THIS VIR_FROM_XEN
+#define XEN_SAVE_DIR LOCALSTATEDIR "/lib/libvirt/xen/save"
 
 static int
 xenUnifiedNodeGetInfo(virConnectPtr conn, virNodeInfoPtr info);
@@ -269,6 +271,7 @@ xenUnifiedOpen(virConnectPtr conn, virConnectAuthPtr auth, unsigned int flags)
 {
     int i, ret = VIR_DRV_OPEN_DECLINED;
     xenUnifiedPrivatePtr priv;
+    char ebuf[1024];
 
 #ifdef __sun
     /*
@@ -408,6 +411,17 @@ xenUnifiedOpen(virConnectPtr conn, virConnectAuthPtr auth, unsigned int flags)
     }
 #endif
 
+    if (virAsprintf(&priv->saveDir, "%s", XEN_SAVE_DIR) == -1) {
+        virReportOOMError();
+        goto fail;
+    }
+
+    if (virFileMakePath(priv->saveDir) < 0) {
+        VIR_ERROR(_("Failed to create save dir '%s': %s"), priv->saveDir,
+                  virStrerror(errno, ebuf, sizeof(ebuf)));
+        goto fail;
+    }
+
     return VIR_DRV_OPEN_SUCCESS;
 
 fail:
@@ -439,6 +453,7 @@ xenUnifiedClose(virConnectPtr conn)
         if (priv->opened[i])
             drivers[i]->xenClose(conn);
 
+    VIR_FREE(priv->saveDir);
     virMutexDestroy(&priv->lock);
     VIR_FREE(conn->privateData);
 
@@ -1082,6 +1097,77 @@ xenUnifiedDomainSave(virDomainPtr dom, const char *to)
     return xenUnifiedDomainSaveFlags(dom, to, NULL, 0);
 }
 
+static char *
+xenUnifiedDomainManagedSavePath(xenUnifiedPrivatePtr priv, virDomainPtr dom)
+{
+    char *ret;
+
+    if (virAsprintf(&ret, "%s/%s.save", priv->saveDir, dom->name) < 0) {
+        virReportOOMError();
+        return NULL;
+    }
+
+    VIR_DEBUG("managed save image: %s", ret);
+    return ret;
+}
+
+static int
+xenUnifiedDomainManagedSave(virDomainPtr dom, unsigned int flags)
+{
+    GET_PRIVATE(dom->conn);
+    char *name;
+    int ret = -1;
+
+    virCheckFlags(0, -1);
+
+    name = xenUnifiedDomainManagedSavePath(priv, dom);
+    if (!name)
+        goto cleanup;
+
+    if (priv->opened[XEN_UNIFIED_XEND_OFFSET])
+        ret = xenDaemonDomainSave(dom, name);
+
+cleanup:
+    VIR_FREE(name);
+    return ret;
+}
+
+static int
+xenUnifiedDomainHasManagedSaveImage(virDomainPtr dom, unsigned int flags)
+{
+    GET_PRIVATE(dom->conn);
+    char *name;
+    int ret = -1;
+
+    virCheckFlags(0, -1);
+
+    name = xenUnifiedDomainManagedSavePath(priv, dom);
+    if (!name)
+        return ret;
+
+    ret = virFileExists(name);
+    VIR_FREE(name);
+    return ret;
+}
+
+static int
+xenUnifiedDomainManagedSaveRemove(virDomainPtr dom, unsigned int flags)
+{
+    GET_PRIVATE(dom->conn);
+    char *name;
+    int ret = -1;
+
+    virCheckFlags(0, -1);
+
+    name = xenUnifiedDomainManagedSavePath(priv, dom);
+    if (!name)
+        return ret;
+
+    ret = unlink(name);
+    VIR_FREE(name);
+    return ret;
+}
+
 static int
 xenUnifiedDomainRestoreFlags(virConnectPtr conn, const char *from,
                              const char *dxml, unsigned int flags)
@@ -1507,15 +1593,35 @@ xenUnifiedDomainCreateWithFlags(virDomainPtr dom, unsigned int flags)
 {
     GET_PRIVATE(dom->conn);
     int i;
+    int ret = -1;
+    char *name = NULL;
 
     virCheckFlags(0, -1);
 
-    for (i = 0; i < XEN_UNIFIED_NR_DRIVERS; ++i)
-        if (priv->opened[i] && drivers[i]->xenDomainCreate &&
-            drivers[i]->xenDomainCreate(dom) == 0)
-            return 0;
+    name = xenUnifiedDomainManagedSavePath(priv, dom);
+    if (!name)
+        goto cleanup;
 
-    return -1;
+    if (virFileExists(name)) {
+        if (priv->opened[XEN_UNIFIED_XEND_OFFSET]) {
+            ret = xenDaemonDomainRestore(dom->conn, name);
+            if (ret == 0)
+                unlink(name);
+        }
+        goto cleanup;
+    }
+
+    for (i = 0; i < XEN_UNIFIED_NR_DRIVERS; ++i) {
+        if (priv->opened[i] && drivers[i]->xenDomainCreate &&
+            drivers[i]->xenDomainCreate(dom) == 0) {
+            ret = 0;
+            goto cleanup;
+        }
+    }
+
+cleanup:
+    VIR_FREE(name);
+    return ret;
 }
 
 static int
@@ -2220,6 +2326,9 @@ static virDriver xenUnifiedDriver = {
     .domainGetState = xenUnifiedDomainGetState, /* 0.9.2 */
     .domainSave = xenUnifiedDomainSave, /* 0.0.3 */
     .domainSaveFlags = xenUnifiedDomainSaveFlags, /* 0.9.4 */
+    .domainManagedSave = xenUnifiedDomainManagedSave, /* 1.0.1 */
+    .domainHasManagedSaveImage = xenUnifiedDomainHasManagedSaveImage, /* 1.0.1 */
+    .domainManagedSaveRemove = xenUnifiedDomainManagedSaveRemove, /* 1.0.1 */
     .domainRestore = xenUnifiedDomainRestore, /* 0.0.3 */
     .domainRestoreFlags = xenUnifiedDomainRestoreFlags, /* 0.9.4 */
     .domainCoreDump = xenUnifiedDomainCoreDump, /* 0.1.9 */

src/xen/xen_driver.h

@@ -200,6 +200,8 @@ struct _xenUnifiedPrivate {
     /* Location of config files, either /etc
      * or /var/lib/xen */
     const char *configDir;
+    /* Location of managed save dir, default /var/lib/libvirt/xen/save */
+    char *saveDir;
 
 # if WITH_XEN_INOTIFY
     /* The inotify fd */