qemu: Don't store path to qemu img

The 'virCommand' helpers already look up the full path to the binary in
PATH if it's not specified. This means that the qemu driver doesn't have
to lookup and store the path to 'qemu-img' in the conf object but rather
can be cleaned up to use this new infrastructure.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

src/qemu/qemu_conf.h

@@ -271,9 +271,6 @@ struct _virQEMUDriver {
     /* Immutable pointer, self-locking APIs */
     virDomainObjList *domains;
 
-    /* Immutable pointer */
-    char *qemuImgBinary;
-
     /* Immutable pointer, lockless APIs. Pointless abstraction */
     ebtablesContext *ebtables;
 

src/qemu/qemu_domain.c

@@ -5671,17 +5671,6 @@ qemuDomainLogAppendMessage(virQEMUDriver *driver,
 }
 
 
-/* Locate an appropriate 'qemu-img' binary.  */
-const char *
-qemuFindQemuImgBinary(virQEMUDriver *driver)
-{
-    if (!driver->qemuImgBinary)
-        virReportError(VIR_ERR_INTERNAL_ERROR,
-                       "%s", _("unable to find qemu-img"));
-
-    return driver->qemuImgBinary;
-}
-
 int
 qemuDomainSnapshotWriteMetadata(virDomainObj *vm,
                                 virDomainMomentObj *snapshot,
@@ -5727,18 +5716,11 @@ qemuDomainSnapshotForEachQcow2Raw(virQEMUDriver *driver,
                                   int ndisks)
 {
     virDomainSnapshotDef *snapdef = virDomainSnapshotObjGetDef(snap);
-    const char *qemuimgbin;
     size_t i;
     bool skipped = false;
 
-    qemuimgbin = qemuFindQemuImgBinary(driver);
-    if (qemuimgbin == NULL) {
-        /* qemuFindQemuImgBinary set the error */
-        return -1;
-    }
-
     for (i = 0; i < ndisks; i++) {
-        g_autoptr(virCommand) cmd = virCommandNewArgList(qemuimgbin, "snapshot",
+        g_autoptr(virCommand) cmd = virCommandNewArgList("qemu-img", "snapshot",
                                                          op, snap->def->name, NULL);
         int format = virDomainDiskGetFormat(def->disks[i]);
 

src/qemu/qemu_domain.h

@@ -665,8 +665,6 @@ int qemuDomainLogAppendMessage(virQEMUDriver *driver,
                                const char *fmt,
                                ...) G_GNUC_PRINTF(3, 4);
 
-const char *qemuFindQemuImgBinary(virQEMUDriver *driver);
-
 int qemuDomainSnapshotWriteMetadata(virDomainObj *vm,
                                     virDomainMomentObj *snapshot,
                                     virDomainXMLOption *xmlopt,

src/qemu/qemu_driver.c

@@ -679,8 +679,6 @@ qemuStateInitialize(bool privileged,
          virPidFileAcquire(cfg->stateDir, "driver", getpid())) < 0)
         goto error;
 
-    qemu_driver->qemuImgBinary = virFindFileInPath("qemu-img");
-
     if (!(qemu_driver->lockManager =
           virLockManagerPluginNew(cfg->lockManagerName ?
                                   cfg->lockManagerName : "nop",
@@ -1065,7 +1063,6 @@ qemuStateCleanup(void)
     virCPUDefFree(qemu_driver->hostcpu);
     virObjectUnref(qemu_driver->caps);
     ebtablesContextFree(qemu_driver->ebtables);
-    VIR_FREE(qemu_driver->qemuImgBinary);
     virObjectUnref(qemu_driver->domains);
     virObjectUnref(qemu_driver->nbdkitCapsCache);
 

src/qemu/qemu_snapshot.c

@@ -185,7 +185,6 @@ qemuSnapshotDomainDefUpdateDisk(virDomainDef *domdef,
 
 /**
  * qemuSnapshotCreateQcow2Files:
- * @driver: QEMU driver
  * @def: domain definition
  * @snapdef: snapshot definition
  * @created: bitmap to store which disks were created
@@ -196,20 +195,15 @@ qemuSnapshotDomainDefUpdateDisk(virDomainDef *domdef,
  * Returns 0 on success, -1 on error.
  */
 static int
-qemuSnapshotCreateQcow2Files(virQEMUDriver *driver,
+qemuSnapshotCreateQcow2Files(virDomainDef *def,
-                             virDomainDef *def,
                              virDomainSnapshotDef *snapdef,
                              virBitmap *created)
 {
     size_t i;
-    const char *qemuImgPath;
     g_auto(virBuffer) buf = VIR_BUFFER_INITIALIZER;
     virDomainSnapshotDiskDef *snapdisk = NULL;
     virDomainDiskDef *defdisk = NULL;
 
-    if (!(qemuImgPath = qemuFindQemuImgBinary(driver)))
-        return -1;
-
     for (i = 0; i < snapdef->ndisks; i++) {
         g_autoptr(virCommand) cmd = NULL;
         snapdisk = &(snapdef->disks[i]);
@@ -225,7 +219,7 @@ qemuSnapshotCreateQcow2Files(virQEMUDriver *driver,
             return -1;
 
         /* creates cmd line args: qemu-img create -f qcow2 -o */
-        if (!(cmd = virCommandNewArgList(qemuImgPath,
+        if (!(cmd = virCommandNewArgList("qemu-img",
                                          "create",
                                          "-f",
                                          virStorageFileFormatTypeToString(snapdisk->src->format),
@@ -281,7 +275,7 @@ qemuSnapshotCreateInactiveExternal(virQEMUDriver *driver,
     /* If reuse is true, then qemuSnapshotPrepare already
      * ensured that the new files exist, and it was up to the user to
      * create them correctly.  */
-    if (!reuse && qemuSnapshotCreateQcow2Files(driver, vm->def, snapdef, created) < 0)
+    if (!reuse && qemuSnapshotCreateQcow2Files(vm->def, snapdef, created) < 0)
         goto cleanup;
 
     /* update disk definitions */
@@ -2300,7 +2294,6 @@ qemuSnapshotRevertExternalActive(virDomainObj *vm,
 
 /**
  * qemuSnapshotRevertExternalInactive:
- * @vm: domain object
  * @tmpsnapdef: temporary snapshot definition
  * @domdef: offline domain definition
  *
@@ -2310,17 +2303,15 @@ qemuSnapshotRevertExternalActive(virDomainObj *vm,
  * Returns 0 on success, -1 on error.
  */
 static int
-qemuSnapshotRevertExternalInactive(virDomainObj *vm,
+qemuSnapshotRevertExternalInactive(virDomainSnapshotDef *tmpsnapdef,
-                                   virDomainSnapshotDef *tmpsnapdef,
                                    virDomainDef *domdef)
 {
-    virQEMUDriver *driver = QEMU_DOMAIN_PRIVATE(vm)->driver;
     g_autoptr(virBitmap) created = NULL;
     int ret = -1;
 
     created = virBitmapNew(tmpsnapdef->ndisks);
 
-    if (qemuSnapshotCreateQcow2Files(driver, domdef, tmpsnapdef, created) < 0)
+    if (qemuSnapshotCreateQcow2Files(domdef, tmpsnapdef, created) < 0)
         goto cleanup;
 
     if (qemuSnapshotDomainDefUpdateDisk(domdef, tmpsnapdef, false) < 0)
@@ -2613,7 +2604,7 @@ qemuSnapshotRevertInactive(virDomainObj *vm,
             return -1;
         }
 
-        if (qemuSnapshotRevertExternalInactive(vm, tmpsnapdef,
+        if (qemuSnapshotRevertExternalInactive(tmpsnapdef,
                                                *inactiveConfig) < 0) {
             return -1;
         }
@@ -3443,22 +3434,16 @@ qemuSnapshotSetInvalid(virDomainObj *vm,
 
 
 static void
-qemuSnapshotUpdateBackingStore(virDomainObj *vm,
+qemuSnapshotUpdateBackingStore(qemuSnapshotDeleteExternalData *data)
-                               qemuSnapshotDeleteExternalData *data)
 {
     GSList *cur = NULL;
-    const char *qemuImgPath;
-    virQEMUDriver *driver = QEMU_DOMAIN_PRIVATE(vm)->driver;
-
-    if (!(qemuImgPath = qemuFindQemuImgBinary(driver)))
-        return;
 
     for (cur = data->disksWithBacking; cur; cur = g_slist_next(cur)) {
         struct _qemuSnapshotDisksWithBackingStoreData *backingData = cur->data;
         g_autoptr(virCommand) cmd = NULL;
 
         /* creates cmd line args: qemu-img create -f qcow2 -o */
-        if (!(cmd = virCommandNewArgList(qemuImgPath,
+        if (!(cmd = virCommandNewArgList("qemu-img",
                                          "rebase",
                                          "-u",
                                          "-F",
@@ -3565,7 +3550,7 @@ qemuSnapshotDiscardExternal(virDomainObj *vm,
 
         qemuBlockJobSyncEnd(vm, data->job, VIR_ASYNC_JOB_SNAPSHOT);
 
-        qemuSnapshotUpdateBackingStore(vm, data);
+        qemuSnapshotUpdateBackingStore(data);
 
         if (qemuSnapshotSetInvalid(vm, data->parentSnap, data->snapDisk, false) < 0)
             goto error;