storage: Complete implementation volume by hash object

Alter the volume logic to use the hash tables instead of forward
linked lists. There are three hash tables to allow for fast lookup
by name, target.path, and key.

Modify the virStoragePoolObjAddVol to place the object in all 3
tables if possible using self locking RWLock on the volumes object.
Conversely when removing the volume, it's a removal of the object
from the various hash tables.

Implement functions to handle remote ForEach and Search Volume
type helpers. These are used by the disk backend in order to
facilitate adding a primary, extended, or logical partition.

Implement the various VolDefFindBy* helpers as simple (and fast)
hash lookups. The NumOfVolumes, GetNames, and ListExport helpers
are all implemented using standard for each hash table calls.

src/conf/virstorageobj.c

@@ -53,11 +53,6 @@ virStorageVolObjListDispose(void *opaque);
 
 
 
-struct _virStorageVolDefList {
-    size_t count;
-    virStorageVolDefPtr *objs;
-};
-
 typedef struct _virStorageVolObj virStorageVolObj;
 typedef virStorageVolObj *virStorageVolObjPtr;
 struct _virStorageVolObj {
@@ -96,7 +91,7 @@ struct _virStoragePoolObj {
     virStoragePoolDefPtr def;
     virStoragePoolDefPtr newDef;
 
-    virStorageVolDefList volumes;
+    virStorageVolObjListPtr volumes;
 };
 
 struct _virStoragePoolObjList {
@@ -133,7 +128,7 @@ virStorageVolObjOnceInit(void)
 VIR_ONCE_GLOBAL_INIT(virStorageVolObj)
 
 
-static virStorageVolObjPtr ATTRIBUTE_UNUSED
+static virStorageVolObjPtr
 virStorageVolObjNew(void)
 {
     virStorageVolObjPtr obj;
@@ -149,7 +144,7 @@ virStorageVolObjNew(void)
 }
 
 
-static void ATTRIBUTE_UNUSED
+static void
 virStorageVolObjEndAPI(virStorageVolObjPtr *obj)
 {
     if (!*obj)
@@ -173,7 +168,7 @@ virStorageVolObjDispose(void *opaque)
 }
 
 
-static virStorageVolObjListPtr ATTRIBUTE_UNUSED
+static virStorageVolObjListPtr
 virStorageVolObjListNew(void)
 {
     virStorageVolObjListPtr vols;
@@ -241,6 +236,11 @@ virStoragePoolObjNew(void)
     if (!(obj = virObjectLockableNew(virStoragePoolObjClass)))
         return NULL;
 
+    if (!(obj->volumes = virStorageVolObjListNew())) {
+        virObjectUnref(obj);
+        return NULL;
+    }
+
     virObjectLock(obj);
     obj->active = false;
     return obj;
@@ -377,6 +377,7 @@ virStoragePoolObjDispose(void *opaque)
         return;
 
     virStoragePoolObjClearVols(obj);
+    virObjectUnref(obj->volumes);
 
     virStoragePoolDefFree(obj->def);
     virStoragePoolDefFree(obj->newDef);
@@ -625,12 +626,9 @@ virStoragePoolSourceFindDuplicateDevices(virStoragePoolObjPtr obj,
 void
 virStoragePoolObjClearVols(virStoragePoolObjPtr obj)
 {
-    size_t i;
+    virHashRemoveAll(obj->volumes->objsKey);
-    for (i = 0; i < obj->volumes.count; i++)
+    virHashRemoveAll(obj->volumes->objsName);
-        virStorageVolDefFree(obj->volumes.objs[i]);
+    virHashRemoveAll(obj->volumes->objsPath);
-
-    VIR_FREE(obj->volumes.objs);
-    obj->volumes.count = 0;
 }
 
 
@@ -638,9 +636,40 @@ int
 virStoragePoolObjAddVol(virStoragePoolObjPtr obj,
                         virStorageVolDefPtr voldef)
 {
-    if (VIR_APPEND_ELEMENT(obj->volumes.objs, obj->volumes.count, voldef) < 0)
+    virStorageVolObjPtr volobj = NULL;
-        return -1;
+    virStorageVolObjListPtr volumes = obj->volumes;
+
+    virObjectRWLockWrite(volumes);
+
+    if (!(volobj = virStorageVolObjNew()))
+        goto error;
+
+    if (virHashAddEntry(volumes->objsKey, voldef->key, volobj) < 0)
+        goto error;
+    virObjectRef(volobj);
+
+    if (virHashAddEntry(volumes->objsName, voldef->name, volobj) < 0) {
+        virHashRemoveEntry(volumes->objsKey, voldef->key);
+        goto error;
+    }
+    virObjectRef(volobj);
+
+    if (virHashAddEntry(volumes->objsPath, voldef->target.path, volobj) < 0) {
+        virHashRemoveEntry(volumes->objsKey, voldef->key);
+        virHashRemoveEntry(volumes->objsName, voldef->name);
+        goto error;
+    }
+    virObjectRef(volobj);
+
+    volobj->voldef = voldef;
+    virObjectRWUnlock(volumes);
+    virStorageVolObjEndAPI(&volobj);
     return 0;
+
+ error:
+    virStorageVolObjEndAPI(&volobj);
+    virObjectRWUnlock(volumes);
+    return -1;
 }
 
 
@@ -648,26 +677,64 @@ void
 virStoragePoolObjRemoveVol(virStoragePoolObjPtr obj,
                            virStorageVolDefPtr voldef)
 {
-    virStoragePoolDefPtr def = virStoragePoolObjGetDef(obj);
+    virStorageVolObjListPtr volumes = obj->volumes;
-    size_t i;
+    virStorageVolObjPtr volobj;
 
-    for (i = 0; i < obj->volumes.count; i++) {
+    virObjectRWLockWrite(volumes);
-        if (obj->volumes.objs[i] == voldef) {
+    volobj = virHashLookup(volumes->objsName, voldef->name);
-            VIR_INFO("Deleting volume '%s' from storage pool '%s'",
+    if (!volobj) {
-                     voldef->name, def->name);
+        VIR_INFO("Cannot find volume '%s' from storage pool '%s'",
-            virStorageVolDefFree(voldef);
+                 voldef->name, obj->def->name);
-
+        virObjectRWUnlock(volumes);
-            VIR_DELETE_ELEMENT(obj->volumes.objs, i, obj->volumes.count);
+        return;
-            return;
-        }
     }
+    VIR_INFO("Deleting volume '%s' from storage pool '%s'",
+             voldef->name, obj->def->name);
+
+    virObjectRef(volobj);
+    virObjectLock(volobj);
+    virHashRemoveEntry(volumes->objsKey, voldef->key);
+    virHashRemoveEntry(volumes->objsName, voldef->name);
+    virHashRemoveEntry(volumes->objsPath, voldef->target.path);
+    virStorageVolObjEndAPI(&volobj);
+
+    virObjectRWUnlock(volumes);
 }
 
 
 size_t
 virStoragePoolObjGetVolumesCount(virStoragePoolObjPtr obj)
 {
-    return obj->volumes.count;
+    size_t nbElems;
+
+    virObjectRWLockRead(obj->volumes);
+    nbElems = virHashSize(obj->volumes->objsKey);
+    virObjectRWUnlock(obj->volumes);
+
+    return nbElems;
+}
+
+
+struct _virStoragePoolObjForEachVolData {
+    virStorageVolObjListIterator iter;
+    const void *opaque;
+};
+
+static int
+virStoragePoolObjForEachVolumeCb(void *payload,
+                                 const void *name ATTRIBUTE_UNUSED,
+                                 void *opaque)
+{
+    int ret = 0;
+    virStorageVolObjPtr volobj = payload;
+    struct _virStoragePoolObjForEachVolData *data = opaque;
+
+    virObjectLock(volobj);
+    if (data->iter(volobj->voldef, data->opaque) < 0)
+        ret = -1;
+    virObjectUnlock(volobj);
+
+    return ret;
 }
 
 
@@ -676,28 +743,58 @@ virStoragePoolObjForEachVolume(virStoragePoolObjPtr obj,
                                virStorageVolObjListIterator iter,
                                const void *opaque)
 {
-    size_t i;
+    struct _virStoragePoolObjForEachVolData data = {
-
+        .iter = iter, .opaque = opaque };
-    for (i = 0; i < obj->volumes.count; i++) {
-        if (iter(obj->volumes.objs[i], opaque) < 0)
-            return -1;
-    }
 
+    virObjectRWLockRead(obj->volumes);
+    virHashForEach(obj->volumes->objsKey, virStoragePoolObjForEachVolumeCb,
+                   &data);
+    virObjectRWUnlock(obj->volumes);
     return 0;
 }
 
 
+struct _virStoragePoolObjSearchVolData {
+    virStorageVolObjListSearcher iter;
+    const void *opaque;
+};
+
+static int
+virStoragePoolObjSearchVolumeCb(const void *payload,
+                                const void *name ATTRIBUTE_UNUSED,
+                                const void *opaque)
+{
+    virStorageVolObjPtr volobj = (virStorageVolObjPtr) payload;
+    struct _virStoragePoolObjSearchVolData *data =
+        (struct _virStoragePoolObjSearchVolData *) opaque;
+    int found = 0;
+
+    virObjectLock(volobj);
+    if (data->iter(volobj->voldef, data->opaque))
+        found = 1;
+    virObjectUnlock(volobj);
+
+    return found;
+}
+
+
 virStorageVolDefPtr
 virStoragePoolObjSearchVolume(virStoragePoolObjPtr obj,
                               virStorageVolObjListSearcher iter,
                               const void *opaque)
 {
-    size_t i;
+    virStorageVolObjPtr volobj;
+    struct _virStoragePoolObjSearchVolData data = {
+        .iter = iter, .opaque = opaque };
 
-    for (i = 0; i < obj->volumes.count; i++) {
+    virObjectRWLockRead(obj->volumes);
-        if (iter(obj->volumes.objs[i], opaque))
+    volobj = virHashSearch(obj->volumes->objsKey,
-            return obj->volumes.objs[i];
+                           virStoragePoolObjSearchVolumeCb,
-    }
+                           &data, NULL);
+    virObjectRWUnlock(obj->volumes);
+
+    if (volobj)
+        return volobj->voldef;
 
     return NULL;
 }
@@ -707,12 +804,14 @@ virStorageVolDefPtr
 virStorageVolDefFindByKey(virStoragePoolObjPtr obj,
                           const char *key)
 {
-    size_t i;
+    virStorageVolObjPtr volobj;
 
-    for (i = 0; i < obj->volumes.count; i++)
+    virObjectRWLockRead(obj->volumes);
-        if (STREQ(obj->volumes.objs[i]->key, key))
+    volobj = virHashLookup(obj->volumes->objsKey, key);
-            return obj->volumes.objs[i];
+    virObjectRWUnlock(obj->volumes);
 
+    if (volobj)
+        return volobj->voldef;
     return NULL;
 }
 
@@ -721,12 +820,14 @@ virStorageVolDefPtr
 virStorageVolDefFindByPath(virStoragePoolObjPtr obj,
                            const char *path)
 {
-    size_t i;
+    virStorageVolObjPtr volobj;
 
-    for (i = 0; i < obj->volumes.count; i++)
+    virObjectRWLockRead(obj->volumes);
-        if (STREQ(obj->volumes.objs[i]->target.path, path))
+    volobj = virHashLookup(obj->volumes->objsPath, path);
-            return obj->volumes.objs[i];
+    virObjectRWUnlock(obj->volumes);
 
+    if (volobj)
+        return volobj->voldef;
     return NULL;
 }
 
@@ -735,34 +836,107 @@ virStorageVolDefPtr
 virStorageVolDefFindByName(virStoragePoolObjPtr obj,
                            const char *name)
 {
-    size_t i;
+    virStorageVolObjPtr volobj;
 
-    for (i = 0; i < obj->volumes.count; i++)
+    virObjectRWLockRead(obj->volumes);
-        if (STREQ(obj->volumes.objs[i]->name, name))
+    volobj = virHashLookup(obj->volumes->objsName, name);
-            return obj->volumes.objs[i];
+    virObjectRWUnlock(obj->volumes);
 
+    if (volobj)
+        return volobj->voldef;
     return NULL;
 }
 
 
+struct _virStorageVolObjCountData {
+    virConnectPtr conn;
+    virStoragePoolVolumeACLFilter filter;
+    virStoragePoolDefPtr pooldef;
+    int count;
+};
+
+
+static int
+virStoragePoolObjNumOfVolumesCb(void *payload,
+                                const void *name ATTRIBUTE_UNUSED,
+                                void *opaque)
+{
+    virStorageVolObjPtr volobj = payload;
+    struct _virStorageVolObjCountData *data = opaque;
+
+    virObjectLock(volobj);
+
+    if (data->filter &&
+        !data->filter(data->conn, data->pooldef, volobj->voldef))
+        goto cleanup;
+
+    data->count++;
+
+ cleanup:
+    virObjectUnlock(volobj);
+    return 0;
+}
+
+
 int
 virStoragePoolObjNumOfVolumes(virStoragePoolObjPtr obj,
                               virConnectPtr conn,
                               virStoragePoolVolumeACLFilter filter)
 {
-    virStoragePoolDefPtr pooldef = obj->def;
+    virStorageVolObjListPtr volumes = obj->volumes;
-    virStorageVolDefListPtr volumes = &obj->volumes;
+    struct _virStorageVolObjCountData data = {
-    int nvolumes = 0;
+        .conn = conn, .filter = filter, .pooldef = obj->def, .count = 0 };
-    size_t i;
 
-    for (i = 0; i < volumes->count; i++) {
+    virObjectRWLockRead(volumes);
-        virStorageVolDefPtr def = volumes->objs[i];
+    virHashForEach(volumes->objsName, virStoragePoolObjNumOfVolumesCb, &data);
-        if (filter && !filter(conn, pooldef, def))
+    virObjectRWUnlock(volumes);
-            continue;
+
-        nvolumes++;
+    return data.count;
+}
+
+
+struct _virStorageVolObjNameData {
+    virConnectPtr conn;
+    virStoragePoolVolumeACLFilter filter;
+    virStoragePoolDefPtr pooldef;
+    bool error;
+    int nnames;
+    int maxnames;
+    char **const names;
+};
+
+static int
+virStoragePoolObjVolumeGetNamesCb(void *payload,
+                                  const void *name ATTRIBUTE_UNUSED,
+                                  void *opaque)
+{
+    virStorageVolObjPtr volobj = payload;
+    struct _virStorageVolObjNameData *data = opaque;
+
+    if (data->error)
+        return 0;
+
+    if (data->maxnames >= 0 && data->nnames == data->maxnames)
+        return 0;
+
+    virObjectLock(volobj);
+
+    if (data->filter &&
+        !data->filter(data->conn, data->pooldef, volobj->voldef))
+        goto cleanup;
+
+    if (data->names) {
+        if (VIR_STRDUP(data->names[data->nnames], volobj->voldef->name) < 0) {
+            data->error = true;
+            goto cleanup;
+        }
     }
 
-    return nvolumes;
+    data->nnames++;
+
+ cleanup:
+    virObjectUnlock(volobj);
+    return 0;
 }
 
 
@@ -773,27 +947,69 @@ virStoragePoolObjVolumeGetNames(virStoragePoolObjPtr obj,
                                 char **const names,
                                 int maxnames)
 {
-    virStoragePoolDefPtr pooldef = obj->def;
+    virStorageVolObjListPtr volumes = obj->volumes;
-    virStorageVolDefListPtr volumes = &obj->volumes;
+    struct _virStorageVolObjNameData data = {
-    int nnames = 0;
+        .conn = conn, .filter = filter, .pooldef = obj->def, .error = false,
-    size_t i;
+        .nnames = 0, .maxnames = maxnames, .names = names };
 
-    for (i = 0; i < volumes->count && nnames < maxnames; i++) {
+    virObjectRWLockRead(volumes);
-        virStorageVolDefPtr def = volumes->objs[i];
+    virHashForEach(volumes->objsName, virStoragePoolObjVolumeGetNamesCb, &data);
-        if (filter && !filter(conn, pooldef, def))
+    virObjectRWUnlock(volumes);
-            continue;
+
-        if (VIR_STRDUP(names[nnames], def->name) < 0)
+    if (data.error)
-            goto failure;
+        goto error;
-        nnames++;
+
+    return data.nnames;
+
+ error:
+    while (--data.nnames)
+        VIR_FREE(data.names[data.nnames]);
+    return -1;
+}
+
+
+struct _virStorageVolObjExportData {
+    virConnectPtr conn;
+    virStoragePoolVolumeACLFilter filter;
+    virStoragePoolDefPtr pooldef;
+    bool error;
+    int nvols;
+    virStorageVolPtr *vols;
+};
+
+static int
+virStoragePoolObjVolumeListExportCb(void *payload,
+                                    const void *name ATTRIBUTE_UNUSED,
+                                    void *opaque)
+{
+    virStorageVolObjPtr volobj = payload;
+    struct _virStorageVolObjExportData *data = opaque;
+    virStorageVolPtr vol = NULL;
+
+    if (data->error)
+        return 0;
+
+    virObjectLock(volobj);
+
+    if (data->filter &&
+        !data->filter(data->conn, data->pooldef, volobj->voldef))
+        goto cleanup;
+
+    if (data->vols) {
+        if (!(vol = virGetStorageVol(data->conn, data->pooldef->name,
+                                     volobj->voldef->name, volobj->voldef->key,
+                                     NULL, NULL))) {
+            data->error = true;
+            goto cleanup;
+        }
+        data->vols[data->nvols] = vol;
     }
 
-    return nnames;
+    data->nvols++;
 
- failure:
+ cleanup:
-    while (--nnames >= 0)
+    virObjectUnlock(volobj);
-        VIR_FREE(names[nnames]);
+    return 0;
-
-    return -1;
 }
 
 
@@ -803,45 +1019,37 @@ virStoragePoolObjVolumeListExport(virConnectPtr conn,
                                   virStorageVolPtr **vols,
                                   virStoragePoolVolumeACLFilter filter)
 {
-    virStoragePoolDefPtr pooldef = obj->def;
+    virStorageVolObjListPtr volumes = obj->volumes;
-    virStorageVolDefListPtr volumes = &obj->volumes;
+    struct _virStorageVolObjExportData data = {
-    int ret = -1;
+        .conn = conn, .filter = filter, .pooldef = obj->def, .error = false,
-    size_t i;
+        .nvols = 0, .vols = NULL };
-    virStorageVolPtr *tmp_vols = NULL;
+
-    virStorageVolPtr vol = NULL;
+    virObjectRWLockRead(volumes);
-    int nvols = 0;
 
-    /* Just returns the volumes count */
     if (!vols) {
-        ret = volumes->count;
+        int ret = virHashSize(volumes->objsName);
-        goto cleanup;
+        virObjectRWUnlock(volumes);
+        return ret;
     }
 
-    if (VIR_ALLOC_N(tmp_vols, volumes->count + 1) < 0)
+    if (VIR_ALLOC_N(data.vols, virHashSize(volumes->objsName) + 1) < 0) {
-        goto cleanup;
+        virObjectRWUnlock(volumes);
-
+        return -1;
-    for (i = 0; i < volumes->count; i++) {
-        virStorageVolDefPtr def = volumes->objs[i];
-        if (filter && !filter(conn, pooldef, def))
-            continue;
-        if (!(vol = virGetStorageVol(conn, pooldef->name, def->name, def->key,
-                                     NULL, NULL)))
-            goto cleanup;
-        tmp_vols[nvols++] = vol;
     }
 
-    *vols = tmp_vols;
+    virHashForEach(volumes->objsName, virStoragePoolObjVolumeListExportCb, &data);
-    tmp_vols = NULL;
+    virObjectRWUnlock(volumes);
-    ret = nvols;
 
- cleanup:
+    if (data.error)
-    if (tmp_vols) {
+        goto error;
-        for (i = 0; i < nvols; i++)
-            virObjectUnref(tmp_vols[i]);
-        VIR_FREE(tmp_vols);
-    }
 
-    return ret;
+    *vols = data.vols;
+
+    return data.nvols;
+
+ error:
+    virObjectListFree(data.vols);
+    return -1;
 }