storage: Introduce storage volume add, delete, count APIs

Create/use virStoragePoolObjAddVol in order to add volumes onto list.

Create/use virStoragePoolObjRemoveVol in order to remove volumes from list.

Create/use virStoragePoolObjGetVolumesCount to get count of volumes on list.

For the storage driver, the logic alters when the volumes.obj list grows
to after we've fetched the volobj. This is an optimization of sorts, but
also doesn't "needlessly" grow the volumes.objs list and then just decr
the count if the virGetStorageVol fails.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

src/conf/virstorageobj.c

@@ -282,6 +282,43 @@ virStoragePoolObjClearVols(virStoragePoolObjPtr obj)
 }
 
 
+int
+virStoragePoolObjAddVol(virStoragePoolObjPtr obj,
+                        virStorageVolDefPtr voldef)
+{
+    if (VIR_APPEND_ELEMENT(obj->volumes.objs, obj->volumes.count, voldef) < 0)
+        return -1;
+    return 0;
+}
+
+
+void
+virStoragePoolObjRemoveVol(virStoragePoolObjPtr obj,
+                           virStorageVolDefPtr voldef)
+{
+    virStoragePoolDefPtr def = virStoragePoolObjGetDef(obj);
+    size_t i;
+
+    for (i = 0; i < obj->volumes.count; i++) {
+        if (obj->volumes.objs[i] == voldef) {
+            VIR_INFO("Deleting volume '%s' from storage pool '%s'",
+                     voldef->name, def->name);
+            virStorageVolDefFree(voldef);
+
+            VIR_DELETE_ELEMENT(obj->volumes.objs, i, obj->volumes.count);
+            return;
+        }
+    }
+}
+
+
+size_t
+virStoragePoolObjGetVolumesCount(virStoragePoolObjPtr obj)
+{
+    return obj->volumes.count;
+}
+
+
 virStorageVolDefPtr
 virStorageVolDefFindByKey(virStoragePoolObjPtr obj,
                           const char *key)

src/conf/virstorageobj.h

@@ -136,6 +136,17 @@ virStoragePoolObjPtr
 virStoragePoolObjFindByName(virStoragePoolObjListPtr pools,
                             const char *name);
 
+int
+virStoragePoolObjAddVol(virStoragePoolObjPtr obj,
+                        virStorageVolDefPtr voldef);
+
+void
+virStoragePoolObjRemoveVol(virStoragePoolObjPtr obj,
+                           virStorageVolDefPtr voldef);
+
+size_t
+virStoragePoolObjGetVolumesCount(virStoragePoolObjPtr obj);
+
 virStorageVolDefPtr
 virStorageVolDefFindByKey(virStoragePoolObjPtr obj,
                           const char *key);

src/libvirt_private.syms

@@ -1053,6 +1053,7 @@ virSecretObjSetValueSize;
 
 
 # conf/virstorageobj.h
+virStoragePoolObjAddVol;
 virStoragePoolObjAssignDef;
 virStoragePoolObjClearVols;
 virStoragePoolObjDecrAsyncjobs;
@@ -1066,6 +1067,7 @@ virStoragePoolObjGetConfigFile;
 virStoragePoolObjGetDef;
 virStoragePoolObjGetNames;
 virStoragePoolObjGetNewDef;
+virStoragePoolObjGetVolumesCount;
 virStoragePoolObjIncrAsyncjobs;
 virStoragePoolObjIsActive;
 virStoragePoolObjIsAutostart;
@@ -1079,6 +1081,7 @@ virStoragePoolObjNew;
 virStoragePoolObjNumOfStoragePools;
 virStoragePoolObjNumOfVolumes;
 virStoragePoolObjRemove;
+virStoragePoolObjRemoveVol;
 virStoragePoolObjSaveDef;
 virStoragePoolObjSetActive;
 virStoragePoolObjSetAutostart;

src/storage/storage_backend_disk.c

@@ -65,8 +65,7 @@ virStorageBackendDiskMakeDataVol(virStoragePoolObjPtr pool,
         if (VIR_ALLOC(vol) < 0)
             return -1;
         if (VIR_STRDUP(vol->name, partname) < 0 ||
-            VIR_APPEND_ELEMENT_COPY(pool->volumes.objs,
-                                    pool->volumes.count, vol) < 0) {
+            virStoragePoolObjAddVol(pool, vol) < 0) {
             virStorageVolDefFree(vol);
             return -1;
         }
@@ -597,7 +596,7 @@ virStorageBackendDiskPartFormat(virStoragePoolObjPtr pool,
                         break;
                     }
                 }
-                if (i == pool->volumes.count) {
+                if (i == virStoragePoolObjGetVolumesCount(pool)) {
                     virReportError(VIR_ERR_INTERNAL_ERROR,
                                    "%s", _("no extended partition found and no primary partition available"));
                     return -1;

src/storage/storage_backend_gluster.c

@@ -386,8 +386,7 @@ virStorageBackendGlusterRefreshPool(virConnectPtr conn ATTRIBUTE_UNUSED,
 
         if (okay < 0)
             goto cleanup;
-        if (vol && VIR_APPEND_ELEMENT(pool->volumes.objs, pool->volumes.count,
-                                      vol) < 0)
+        if (vol && virStoragePoolObjAddVol(pool, vol) < 0)
             goto cleanup;
     }
     if (errno) {

src/storage/storage_backend_logical.c

@@ -356,9 +356,9 @@ virStorageBackendLogicalMakeVol(char **const groups,
     if (virStorageBackendLogicalParseVolExtents(vol, groups) < 0)
         goto cleanup;
 
-    if (is_new_vol &&
-        VIR_APPEND_ELEMENT(pool->volumes.objs, pool->volumes.count, vol) < 0)
+    if (is_new_vol && virStoragePoolObjAddVol(pool, vol) < 0)
         goto cleanup;
+    vol = NULL;
 
     ret = 0;
 

src/storage/storage_backend_mpath.c

@@ -71,8 +71,9 @@ virStorageBackendMpathNewVol(virStoragePoolObjPtr pool,
     if (VIR_STRDUP(vol->key, vol->target.path) < 0)
         goto cleanup;
 
-    if (VIR_APPEND_ELEMENT_COPY(pool->volumes.objs, pool->volumes.count, vol) < 0)
+    if (virStoragePoolObjAddVol(pool, vol) < 0)
         goto cleanup;
+
     pool->def->capacity += vol->target.capacity;
     pool->def->allocation += vol->target.allocation;
     ret = 0;

src/storage/storage_backend_rbd.c

@@ -506,7 +506,7 @@ virStorageBackendRBDRefreshPool(virConnectPtr conn,
             goto cleanup;
         }
 
-        if (VIR_APPEND_ELEMENT(pool->volumes.objs, pool->volumes.count, vol) < 0) {
+        if (virStoragePoolObjAddVol(pool, vol) < 0) {
             virStorageVolDefFree(vol);
             virStoragePoolObjClearVols(pool);
             goto cleanup;
@@ -514,7 +514,7 @@ virStorageBackendRBDRefreshPool(virConnectPtr conn,
     }
 
     VIR_DEBUG("Found %zu images in RBD pool %s",
-              pool->volumes.count, pool->def->source.name);
+              virStoragePoolObjGetVolumesCount(pool), pool->def->source.name);
 
     ret = 0;
 

src/storage/storage_backend_sheepdog.c

@@ -130,11 +130,9 @@ virStorageBackendSheepdogAddVolume(virConnectPtr conn ATTRIBUTE_UNUSED,
     if (virStorageBackendSheepdogRefreshVol(conn, pool, vol) < 0)
         goto error;
 
-    if (VIR_EXPAND_N(pool->volumes.objs, pool->volumes.count, 1) < 0)
+    if (virStoragePoolObjAddVol(pool, vol) < 0)
         goto error;
 
-    pool->volumes.objs[pool->volumes.count - 1] = vol;
-
     return 0;
 
  error:

src/storage/storage_backend_zfs.c

@@ -161,11 +161,9 @@ virStorageBackendZFSParseVol(virStoragePoolObjPtr pool,
     if (volume->target.allocation < volume->target.capacity)
         volume->target.sparse = true;
 
-    if (is_new_vol &&
-        VIR_APPEND_ELEMENT(pool->volumes.objs,
-                           pool->volumes.count,
-                           volume) < 0)
+    if (is_new_vol && virStoragePoolObjAddVol(pool, volume) < 0)
         goto cleanup;
+    volume = NULL;
 
     ret = 0;
  cleanup:

src/storage/storage_driver.c

@@ -1626,25 +1626,6 @@ storagePoolLookupByTargetPath(virConnectPtr conn,
 }
 
 
-static void
-storageVolRemoveFromPool(virStoragePoolObjPtr obj,
-                         virStorageVolDefPtr voldef)
-{
-    size_t i;
-
-    for (i = 0; i < obj->volumes.count; i++) {
-        if (obj->volumes.objs[i] == voldef) {
-            VIR_INFO("Deleting volume '%s' from storage pool '%s'",
-                     voldef->name, obj->def->name);
-            virStorageVolDefFree(voldef);
-
-            VIR_DELETE_ELEMENT(obj->volumes.objs, i, obj->volumes.count);
-            break;
-        }
-    }
-}
-
-
 static int
 storageVolDeleteInternal(virStorageVolPtr vol,
                          virStorageBackendPtr backend,
@@ -1676,7 +1657,7 @@ storageVolDeleteInternal(virStorageVolPtr vol,
         }
     }
 
-    storageVolRemoveFromPool(obj, voldef);
+    virStoragePoolObjRemoveVol(obj, voldef);
     ret = 0;
 
  cleanup:
@@ -1815,24 +1796,19 @@ storageVolCreateXML(virStoragePoolPtr pool,
         goto cleanup;
     }
 
-    if (VIR_REALLOC_N(obj->volumes.objs,
-                      obj->volumes.count + 1) < 0)
-        goto cleanup;
-
     /* Wipe any key the user may have suggested, as volume creation
      * will generate the canonical key.  */
     VIR_FREE(voldef->key);
     if (backend->createVol(pool->conn, obj, voldef) < 0)
         goto cleanup;
 
-    obj->volumes.objs[obj->volumes.count++] = voldef;
-    newvol = virGetStorageVol(pool->conn, obj->def->name, voldef->name,
-                              voldef->key, NULL, NULL);
-    if (!newvol) {
-        obj->volumes.count--;
+    if (!(newvol = virGetStorageVol(pool->conn, obj->def->name, voldef->name,
+                                    voldef->key, NULL, NULL)))
         goto cleanup;
-    }
 
+    /* NB: Upon success voldef "owned" by storage pool for deletion purposes */
+    if (virStoragePoolObjAddVol(obj, voldef) < 0)
+        goto cleanup;
 
     if (backend->buildVol) {
         int buildret;
@@ -1867,7 +1843,7 @@ storageVolCreateXML(virStoragePoolPtr pool,
 
         if (buildret < 0) {
             /* buildVol handles deleting volume on failure */
-            storageVolRemoveFromPool(obj, voldef);
+            virStoragePoolObjRemoveVol(obj, voldef);
             voldef = NULL;
             goto cleanup;
         }
@@ -2018,9 +1994,6 @@ storageVolCreateXMLFrom(virStoragePoolPtr pool,
         backend->refreshVol(pool->conn, obj, voldefsrc) < 0)
         goto cleanup;
 
-    if (VIR_REALLOC_N(obj->volumes.objs, obj->volumes.count + 1) < 0)
-        goto cleanup;
-
     /* 'Define' the new volume so we get async progress reporting.
      * Wipe any key the user may have suggested, as volume creation
      * will generate the canonical key.  */
@@ -2037,13 +2010,13 @@ storageVolCreateXMLFrom(virStoragePoolPtr pool,
 
     memcpy(shadowvol, voldef, sizeof(*voldef));
 
-    obj->volumes.objs[obj->volumes.count++] = voldef;
-    newvol = virGetStorageVol(pool->conn, obj->def->name, voldef->name,
-                              voldef->key, NULL, NULL);
-    if (!newvol) {
-        obj->volumes.count--;
+    if (!(newvol = virGetStorageVol(pool->conn, obj->def->name, voldef->name,
+                                    voldef->key, NULL, NULL)))
+        goto cleanup;
+
+    /* NB: Upon success voldef "owned" by storage pool for deletion purposes */
+    if (virStoragePoolObjAddVol(obj, voldef) < 0)
         goto cleanup;
-    }
 
     /* Drop the pool lock during volume allocation */
     obj->asyncjobs++;

src/storage/storage_util.c

@@ -3623,13 +3623,13 @@ virStorageBackendRefreshLocal(virConnectPtr conn ATTRIBUTE_UNUSED,
             goto cleanup;
         }
 
-        if (VIR_APPEND_ELEMENT(pool->volumes.objs, pool->volumes.count, vol) < 0)
+        if (virStoragePoolObjAddVol(pool, vol) < 0)
             goto cleanup;
+        vol = NULL;
     }
     if (direrr < 0)
         goto cleanup;
     VIR_DIR_CLOSE(dir);
-    vol = NULL;
 
     if (VIR_ALLOC(target))
         goto cleanup;
@@ -3811,10 +3811,10 @@ virStorageBackendSCSINewLun(virStoragePoolObjPtr pool,
     pool->def->capacity += vol->target.capacity;
     pool->def->allocation += vol->target.allocation;
 
-    if (VIR_APPEND_ELEMENT(pool->volumes.objs, pool->volumes.count, vol) < 0)
+    if (virStoragePoolObjAddVol(pool, vol) < 0)
         goto cleanup;
-
     vol = NULL;
+
     retval = 0;
 
  cleanup:

src/test/test_driver.c

@@ -1079,7 +1079,8 @@ testOpenVolumesForPool(const char *file,
 
         if (!def->key && VIR_STRDUP(def->key, def->target.path) < 0)
             goto error;
-        if (VIR_APPEND_ELEMENT_COPY(obj->volumes.objs, obj->volumes.count, def) < 0)
+
+        if (virStoragePoolObjAddVol(obj, def) < 0)
             goto error;
 
         obj->def->allocation += def->target.allocation;
@@ -5011,8 +5012,7 @@ testStorageVolCreateXML(virStoragePoolPtr pool,
         goto cleanup;
 
     if (VIR_STRDUP(privvol->key, privvol->target.path) < 0 ||
-        VIR_APPEND_ELEMENT_COPY(obj->volumes.objs,
-                                obj->volumes.count, privvol) < 0)
+        virStoragePoolObjAddVol(obj, privvol) < 0)
         goto cleanup;
 
     obj->def->allocation += privvol->target.allocation;
@@ -5079,8 +5079,7 @@ testStorageVolCreateXMLFrom(virStoragePoolPtr pool,
         goto cleanup;
 
     if (VIR_STRDUP(privvol->key, privvol->target.path) < 0 ||
-        VIR_APPEND_ELEMENT_COPY(obj->volumes.objs,
-                                obj->volumes.count, privvol) < 0)
+        virStoragePoolObjAddVol(obj, privvol) < 0)
         goto cleanup;
 
     obj->def->allocation += privvol->target.allocation;
@@ -5105,7 +5104,6 @@ testStorageVolDelete(virStorageVolPtr vol,
     testDriverPtr privconn = vol->conn->privateData;
     virStoragePoolObjPtr obj;
     virStorageVolDefPtr privvol;
-    size_t i;
     int ret = -1;
 
     virCheckFlags(0, -1);
@@ -5119,14 +5117,8 @@ testStorageVolDelete(virStorageVolPtr vol,
     obj->def->allocation -= privvol->target.allocation;
     obj->def->available = (obj->def->capacity - obj->def->allocation);
 
-    for (i = 0; i < obj->volumes.count; i++) {
-        if (obj->volumes.objs[i] == privvol) {
-            virStorageVolDefFree(privvol);
+    virStoragePoolObjRemoveVol(obj, privvol);
 
-            VIR_DELETE_ELEMENT(obj->volumes.objs, i, obj->volumes.count);
-            break;
-        }
-    }
     ret = 0;
 
  cleanup: