qemu: snapshot: Add support for external active snapshots on gluster

Add support for gluster backed images as sources for snapshots in the
qemu driver. This will also simplify adding further network backed
volumes as sources for snapshot in case qemu will support them.

diff --git a/docs/formatsnapshot.html.in b/docs/formatsnapshot.html.in
index 44ed4fdab03ff6deeb33d285acb4e510751178e3..1f9a6c68cf04d7ec63bd4a0a50181ddf9a781c21 100644 (file)
--- a/docs/formatsnapshot.html.in
+++ b/docs/formatsnapshot.html.in
@@ -183,8 +183,9 @@
             documentation for further information.
 
             Libvirt currently supports the <code>type</code> element in the qemu
-            driver and supported values are <code>file</code> and
-            <code>block</code> <span class="since">(since 1.2.2)</span>.
+            driver and supported values are <code>file</code>, <code>block</code>
+            and <code>network</code> with a protocol of <code>gluster</code>
+            <span class="since">(since 1.2.2)</span>.
           </dd>
         </dl>
       </dd>

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index e9908f9e65d2683586bb4f25dda5040931614e4b..bb8756fd4631c30f459857c48d24ea02482b4763 100644 (file)
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3822,7 +3822,7 @@ cleanup:
 }
 
 
-static int
+int
 qemuGetDriveSourceString(int type,
                          const char *src,
                          int protocol,

diff --git a/src/qemu/qemu_command.h b/src/qemu/qemu_command.h
index 82ca4b30bf85a1333b80df27c41ed93ab70c6138..ebb0b1d21044118a1e8b7fdc4ad7f1b608e26dea 100644 (file)
--- a/src/qemu/qemu_command.h
+++ b/src/qemu/qemu_command.h
@@ -313,4 +313,13 @@ qemuParseKeywords(const char *str,
                   int *retnkeywords,
                   int allowEmptyValue);
 
+int qemuGetDriveSourceString(int type,
+                             const char *src,
+                             int protocol,
+                             size_t nhosts,
+                             virDomainDiskHostDefPtr hosts,
+                             const char *username,
+                             const char *secret,
+                             char **path);
+
 #endif /* __QEMU_COMMAND_H__*/

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 04cd13b5ffbd459a7753a78d540761d8bb20b45e..6ea837ef0409f4864a8fb0fa58803d8710f8e36e 100644 (file)
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -11933,6 +11933,24 @@ cleanup:
     return ret;
 }
 
+
+static int
+qemuDomainSnapshotDiskGetSourceString(virDomainSnapshotDiskDefPtr disk,
+                                      char **source)
+{
+    *source = NULL;
+
+    return qemuGetDriveSourceString(virDomainSnapshotDiskGetActualType(disk),
+                                    disk->file,
+                                    disk->protocol,
+                                    disk->nhosts,
+                                    disk->hosts,
+                                    NULL,
+                                    NULL,
+                                    source);
+}
+
+
 typedef enum {
     VIR_DISK_CHAIN_NO_ACCESS,
     VIR_DISK_CHAIN_READ_ONLY,
@@ -12330,6 +12348,29 @@ qemuDomainSnapshotPrepareDiskExternalOverlayActive(virDomainSnapshotDiskDefPtr d
         return 0;
 
     case VIR_DOMAIN_DISK_TYPE_NETWORK:
+        switch ((enum virDomainDiskProtocol) disk->protocol) {
+        case VIR_DOMAIN_DISK_PROTOCOL_GLUSTER:
+            return 0;
+
+        case VIR_DOMAIN_DISK_PROTOCOL_NBD:
+        case VIR_DOMAIN_DISK_PROTOCOL_RBD:
+        case VIR_DOMAIN_DISK_PROTOCOL_SHEEPDOG:
+        case VIR_DOMAIN_DISK_PROTOCOL_ISCSI:
+        case VIR_DOMAIN_DISK_PROTOCOL_HTTP:
+        case VIR_DOMAIN_DISK_PROTOCOL_HTTPS:
+        case VIR_DOMAIN_DISK_PROTOCOL_FTP:
+        case VIR_DOMAIN_DISK_PROTOCOL_FTPS:
+        case VIR_DOMAIN_DISK_PROTOCOL_TFTP:
+        case VIR_DOMAIN_DISK_PROTOCOL_LAST:
+            virReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("external active snapshots are not supported on "
+                             "'network' disks using '%s' protocol"),
+                           virDomainDiskProtocolTypeToString(disk->protocol));
+            return -1;
+
+        }
+        break;
+
     case VIR_DOMAIN_DISK_TYPE_DIR:
     case VIR_DOMAIN_DISK_TYPE_VOLUME:
     case VIR_DOMAIN_DISK_TYPE_LAST:
@@ -12637,6 +12678,9 @@ qemuDomainSnapshotCreateSingleDiskActive(virQEMUDriverPtr driver,
     qemuDomainObjPrivatePtr priv = vm->privateData;
     char *device = NULL;
     char *source = NULL;
+    char *newsource = NULL;
+    virDomainDiskHostDefPtr newhosts = NULL;
+    virDomainDiskHostDefPtr persistHosts = NULL;
     int format = snap->format;
     const char *formatStr = NULL;
     char *persistSource = NULL;
@@ -12651,8 +12695,7 @@ qemuDomainSnapshotCreateSingleDiskActive(virQEMUDriverPtr driver,
         return -1;
     }
 
-    if (virAsprintf(&device, "drive-%s", disk->info.alias) < 0 ||
-        (persistDisk && VIR_STRDUP(persistSource, source) < 0))
+    if (virAsprintf(&device, "drive-%s", disk->info.alias) < 0)
         goto cleanup;
 
     /* XXX Here, we know we are about to alter disk->backingChain if
@@ -12666,13 +12709,21 @@ qemuDomainSnapshotCreateSingleDiskActive(virQEMUDriverPtr driver,
     if (!(snapfile = virStorageFileInitFromSnapshotDef(snap)))
         goto cleanup;
 
+    if (qemuDomainSnapshotDiskGetSourceString(snap, &source) < 0)
+        goto cleanup;
+
+    if (VIR_STRDUP(newsource, snap->file) < 0)
+        goto cleanup;
+
+    if (persistDisk &&
+        VIR_STRDUP(persistSource, snap->file) < 0)
+        goto cleanup;
+
     switch (snap->type) {
     case VIR_DOMAIN_DISK_TYPE_BLOCK:
         reuse = true;
         /* fallthrough */
     case VIR_DOMAIN_DISK_TYPE_FILE:
-        if (VIR_STRDUP(source, snap->file) < 0)
-            goto cleanup;
 
         /* create the stub file and set selinux labels; manipulate disk in
          * place, in a way that can be reverted on failure. */
@@ -12692,6 +12743,27 @@ qemuDomainSnapshotCreateSingleDiskActive(virQEMUDriverPtr driver,
         }
         break;
 
+    case VIR_DOMAIN_DISK_TYPE_NETWORK:
+        switch (snap->protocol) {
+        case VIR_DOMAIN_DISK_PROTOCOL_GLUSTER:
+            if (!(newhosts = virDomainDiskHostDefCopy(snap->nhosts, snap->hosts)))
+                goto cleanup;
+
+            if (persistDisk &&
+                !(persistHosts = virDomainDiskHostDefCopy(snap->nhosts, snap->hosts)))
+                goto cleanup;
+
+            break;
+
+        default:
+            virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
+                           _("snapshots on volumes using '%s' protocol "
+                             "are not supported"),
+                           virDomainDiskProtocolTypeToString(snap->protocol));
+            goto cleanup;
+        }
+        break;
+
     default:
         virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
                        _("snapshots are not supported on '%s' volumes"),
@@ -12727,17 +12799,33 @@ qemuDomainSnapshotCreateSingleDiskActive(virQEMUDriverPtr driver,
 
     /* Update vm in place to match changes.  */
     need_unlink = false;
+
     VIR_FREE(disk->src);
-    disk->src = source;
-    source = NULL;
+    virDomainDiskHostDefFree(disk->nhosts, disk->hosts);
+
+    disk->src = newsource;
     disk->format = format;
     disk->type = snap->type;
+    disk->protocol = snap->protocol;
+    disk->nhosts = snap->nhosts;
+    disk->hosts = newhosts;
+
+    newsource = NULL;
+    newhosts = NULL;
+
     if (persistDisk) {
         VIR_FREE(persistDisk->src);
+        virDomainDiskHostDefFree(persistDisk->nhosts, persistDisk->hosts);
+
         persistDisk->src = persistSource;
-        persistSource = NULL;
         persistDisk->format = format;
         persistDisk->type = snap->type;
+        persistDisk->protocol = snap->protocol;
+        persistDisk->nhosts = snap->nhosts;
+        persistDisk->hosts = persistHosts;
+
+        persistSource = NULL;
+        persistHosts = NULL;
     }
 
 cleanup:
@@ -12746,7 +12834,10 @@ cleanup:
     virStorageFileFree(snapfile);
     VIR_FREE(device);
     VIR_FREE(source);
+    VIR_FREE(newsource);
     VIR_FREE(persistSource);
+    virDomainDiskHostDefFree(snap->nhosts, newhosts);
+    virDomainDiskHostDefFree(snap->nhosts, persistHosts);
     return ret;
 }
 
@@ -12785,12 +12876,20 @@ qemuDomainSnapshotUndoSingleDiskActive(virQEMUDriverPtr driver,
     source = NULL;
     disk->format = origdisk->format;
     disk->type = origdisk->type;
+    disk->protocol = origdisk->protocol;
+    virDomainDiskHostDefFree(disk->nhosts, disk->hosts);
+    disk->nhosts = origdisk->nhosts;
+    disk->hosts = virDomainDiskHostDefCopy(origdisk->nhosts, origdisk->hosts);
     if (persistDisk) {
         VIR_FREE(persistDisk->src);
         persistDisk->src = persistSource;
         persistSource = NULL;
         persistDisk->format = origdisk->format;
         persistDisk->type = origdisk->type;
+        persistDisk->protocol = origdisk->protocol;
+        virDomainDiskHostDefFree(persistDisk->nhosts, persistDisk->hosts);
+        persistDisk->nhosts = origdisk->nhosts;
+        persistDisk->hosts = virDomainDiskHostDefCopy(origdisk->nhosts, origdisk->hosts);
     }
 
 cleanup: