[libvirt] [PATCHv4 26/51] snapshot: refactor some qemu code

Prepare for code sharing. No semantic change. * src/qemu/qemu_driver.c (qemuFindQemuImgBinary) (qemuDomainSnapshotWriteMetadata) (qemuDomainSnapshotDiscard): Float up. (qemuDomainSnapshotDiscardDescendant): Likewise, and rename... (qemuDomainSnapshotDiscardAll): ...for generic use. (qemuDomainSnapshotDelete): Update caller. --- src/qemu/qemu_driver.c | 380 ++++++++++++++++++++++++------------------------ 1 files changed, 192 insertions(+), 188 deletions(-) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 38a21db..2db0d62 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -1582,6 +1582,197 @@ cleanup: } +/* Locate an appropriate 'qemu-img' binary. */ +static char * +qemuFindQemuImgBinary(void) +{ + char *ret; + + ret = virFindFileInPath("kvm-img"); + if (ret == NULL) + ret = virFindFileInPath("qemu-img"); + if (ret == NULL) + qemuReportError(VIR_ERR_INTERNAL_ERROR, + "%s", _("unable to find kvm-img or qemu-img")); + + return ret; +} + +static int +qemuDomainSnapshotWriteMetadata(virDomainObjPtr vm, + virDomainSnapshotObjPtr snapshot, + char *snapshotDir) +{ + int fd = -1; + char *newxml = NULL; + int ret = -1; + char *snapDir = NULL; + char *snapFile = NULL; + char uuidstr[VIR_UUID_STRING_BUFLEN]; + + virUUIDFormat(vm->def->uuid, uuidstr); + newxml = virDomainSnapshotDefFormat(uuidstr, snapshot->def, 1); + if (newxml == NULL) { + virReportOOMError(); + return -1; + } + + if (virAsprintf(&snapDir, "%s/%s", snapshotDir, vm->def->name) < 0) { + virReportOOMError(); + goto cleanup; + } + if (virFileMakePath(snapDir) < 0) { + virReportSystemError(errno, _("cannot create snapshot directory '%s'"), + snapDir); + goto cleanup; + } + + if (virAsprintf(&snapFile, "%s/%s.xml", snapDir, snapshot->def->name) < 0) { + virReportOOMError(); + goto cleanup; + } + fd = open(snapFile, O_CREAT|O_TRUNC|O_WRONLY, S_IRUSR|S_IWUSR); + if (fd < 0) { + qemuReportError(VIR_ERR_OPERATION_FAILED, + _("failed to create snapshot file '%s'"), snapFile); + goto cleanup; + } + if (safewrite(fd, newxml, strlen(newxml)) != strlen(newxml)) { + virReportSystemError(errno, _("Failed to write snapshot data to %s"), + snapFile); + goto cleanup; + } + + ret = 0; + +cleanup: + VIR_FREE(snapFile); + VIR_FREE(snapDir); + VIR_FREE(newxml); + VIR_FORCE_CLOSE(fd); + return ret; +} + +/* Discard one snapshot (or its metadata), without reparenting any children. */ +static int +qemuDomainSnapshotDiscard(struct qemud_driver *driver, + virDomainObjPtr vm, + virDomainSnapshotObjPtr snap, + bool update_current, + bool metadata_only) +{ + const char *qemuimgarg[] = { NULL, "snapshot", "-d", NULL, NULL, NULL }; + char *snapFile = NULL; + int ret = -1; + int i; + qemuDomainObjPrivatePtr priv; + virDomainSnapshotObjPtr parentsnap = NULL; + + if (!metadata_only) { + if (!virDomainObjIsActive(vm)) { + qemuimgarg[0] = qemuFindQemuImgBinary(); + if (qemuimgarg[0] == NULL) + /* qemuFindQemuImgBinary set the error */ + goto cleanup; + + qemuimgarg[3] = snap->def->name; + + for (i = 0; i < vm->def->ndisks; i++) { + /* FIXME: we also need to handle LVM here */ + if (vm->def->disks[i]->device == VIR_DOMAIN_DISK_DEVICE_DISK) { + if (!vm->def->disks[i]->driverType || + STRNEQ(vm->def->disks[i]->driverType, "qcow2")) { + /* we continue on even in the face of error, since other + * disks in this VM may have this snapshot in place + */ + continue; + } + + qemuimgarg[4] = vm->def->disks[i]->src; + + if (virRun(qemuimgarg, NULL) < 0) { + /* we continue on even in the face of error, since other + * disks in this VM may have this snapshot in place + */ + continue; + } + } + } + } else { + priv = vm->privateData; + qemuDomainObjEnterMonitorWithDriver(driver, vm); + /* we continue on even in the face of error */ + qemuMonitorDeleteSnapshot(priv->mon, snap->def->name); + qemuDomainObjExitMonitorWithDriver(driver, vm); + } + } + + if (virAsprintf(&snapFile, "%s/%s/%s.xml", driver->snapshotDir, + vm->def->name, snap->def->name) < 0) { + virReportOOMError(); + goto cleanup; + } + + if (snap == vm->current_snapshot) { + if (update_current && snap->def->parent) { + parentsnap = virDomainSnapshotFindByName(&vm->snapshots, + snap->def->parent); + if (!parentsnap) { + VIR_WARN("missing parent snapshot matching name '%s'", + snap->def->parent); + } else { + parentsnap->def->current = true; + if (qemuDomainSnapshotWriteMetadata(vm, parentsnap, + driver->snapshotDir) < 0) { + VIR_WARN("failed to set parent snapshot '%s' as current", + snap->def->parent); + parentsnap->def->current = false; + parentsnap = NULL; + } + } + } + vm->current_snapshot = parentsnap; + } + + if (unlink(snapFile) < 0) + VIR_WARN("Failed to unlink %s", snapFile); + virDomainSnapshotObjListRemove(&vm->snapshots, snap); + + ret = 0; + +cleanup: + VIR_FREE(snapFile); + VIR_FREE(qemuimgarg[0]); + + return ret; +} + +struct snap_remove { + struct qemud_driver *driver; + virDomainObjPtr vm; + int err; + bool metadata_only; + bool current; +}; + +/* Hash iterator callback to discard multiple snapshots. */ +static void +qemuDomainSnapshotDiscardAll(void *payload, + const void *name ATTRIBUTE_UNUSED, + void *data) +{ + virDomainSnapshotObjPtr snap = payload; + struct snap_remove *curr = data; + int err; + + if (snap->def->current) + curr->current = true; + err = qemuDomainSnapshotDiscard(curr->driver, curr->vm, snap, false, + curr->metadata_only); + if (err && !curr->err) + curr->err = err; +} + static int qemuDomainDestroyFlags(virDomainPtr dom, unsigned int flags) @@ -8391,75 +8582,6 @@ cleanup: return ret; } -static char *qemuFindQemuImgBinary(void) -{ - char *ret; - - ret = virFindFileInPath("kvm-img"); - if (ret == NULL) - ret = virFindFileInPath("qemu-img"); - if (ret == NULL) - qemuReportError(VIR_ERR_INTERNAL_ERROR, - "%s", _("unable to find kvm-img or qemu-img")); - - return ret; -} - -static int qemuDomainSnapshotWriteMetadata(virDomainObjPtr vm, - virDomainSnapshotObjPtr snapshot, - char *snapshotDir) -{ - int fd = -1; - char *newxml = NULL; - int ret = -1; - char *snapDir = NULL; - char *snapFile = NULL; - char uuidstr[VIR_UUID_STRING_BUFLEN]; - - virUUIDFormat(vm->def->uuid, uuidstr); - newxml = virDomainSnapshotDefFormat(uuidstr, snapshot->def, 1); - if (newxml == NULL) { - virReportOOMError(); - return -1; - } - - if (virAsprintf(&snapDir, "%s/%s", snapshotDir, vm->def->name) < 0) { - virReportOOMError(); - goto cleanup; - } - if (virFileMakePath(snapDir) < 0) { - virReportSystemError(errno, _("cannot create snapshot directory '%s'"), - snapDir); - goto cleanup; - } - - if (virAsprintf(&snapFile, "%s/%s.xml", snapDir, snapshot->def->name) < 0) { - virReportOOMError(); - goto cleanup; - } - fd = open(snapFile, O_CREAT|O_TRUNC|O_WRONLY, S_IRUSR|S_IWUSR); - if (fd < 0) { - qemuReportError(VIR_ERR_OPERATION_FAILED, - _("failed to create snapshot file '%s'"), snapFile); - goto cleanup; - } - if (safewrite(fd, newxml, strlen(newxml)) != strlen(newxml)) { - virReportSystemError(errno, _("Failed to write snapshot data to %s"), - snapFile); - goto cleanup; - } - - ret = 0; - -cleanup: - VIR_FREE(snapFile); - VIR_FREE(snapDir); - VIR_FREE(newxml); - VIR_FORCE_CLOSE(fd); - return ret; -} - - static int qemuDomainSnapshotIsAllowed(virDomainObjPtr vm) { int i; @@ -9219,124 +9341,6 @@ cleanup: return ret; } -static int -qemuDomainSnapshotDiscard(struct qemud_driver *driver, - virDomainObjPtr vm, - virDomainSnapshotObjPtr snap, - bool update_current, - bool metadata_only) -{ - const char *qemuimgarg[] = { NULL, "snapshot", "-d", NULL, NULL, NULL }; - char *snapFile = NULL; - int ret = -1; - int i; - qemuDomainObjPrivatePtr priv; - virDomainSnapshotObjPtr parentsnap = NULL; - - if (!metadata_only) { - if (!virDomainObjIsActive(vm)) { - qemuimgarg[0] = qemuFindQemuImgBinary(); - if (qemuimgarg[0] == NULL) - /* qemuFindQemuImgBinary set the error */ - goto cleanup; - - qemuimgarg[3] = snap->def->name; - - for (i = 0; i < vm->def->ndisks; i++) { - /* FIXME: we also need to handle LVM here */ - if (vm->def->disks[i]->device == VIR_DOMAIN_DISK_DEVICE_DISK) { - if (!vm->def->disks[i]->driverType || - STRNEQ(vm->def->disks[i]->driverType, "qcow2")) { - /* we continue on even in the face of error, since other - * disks in this VM may have this snapshot in place - */ - continue; - } - - qemuimgarg[4] = vm->def->disks[i]->src; - - if (virRun(qemuimgarg, NULL) < 0) { - /* we continue on even in the face of error, since other - * disks in this VM may have this snapshot in place - */ - continue; - } - } - } - } else { - priv = vm->privateData; - qemuDomainObjEnterMonitorWithDriver(driver, vm); - /* we continue on even in the face of error */ - qemuMonitorDeleteSnapshot(priv->mon, snap->def->name); - qemuDomainObjExitMonitorWithDriver(driver, vm); - } - } - - if (virAsprintf(&snapFile, "%s/%s/%s.xml", driver->snapshotDir, - vm->def->name, snap->def->name) < 0) { - virReportOOMError(); - goto cleanup; - } - - if (snap == vm->current_snapshot) { - if (update_current && snap->def->parent) { - parentsnap = virDomainSnapshotFindByName(&vm->snapshots, - snap->def->parent); - if (!parentsnap) { - VIR_WARN("missing parent snapshot matching name '%s'", - snap->def->parent); - } else { - parentsnap->def->current = true; - if (qemuDomainSnapshotWriteMetadata(vm, parentsnap, - driver->snapshotDir) < 0) { - VIR_WARN("failed to set parent snapshot '%s' as current", - snap->def->parent); - parentsnap->def->current = false; - parentsnap = NULL; - } - } - } - vm->current_snapshot = parentsnap; - } - - if (unlink(snapFile) < 0) - VIR_WARN("Failed to unlink %s", snapFile); - virDomainSnapshotObjListRemove(&vm->snapshots, snap); - - ret = 0; - -cleanup: - VIR_FREE(snapFile); - VIR_FREE(qemuimgarg[0]); - - return ret; -} - -struct snap_remove { - struct qemud_driver *driver; - virDomainObjPtr vm; - bool metadata_only; - int err; - bool current; -}; - -static void -qemuDomainSnapshotDiscardDescendant(void *payload, - const void *name ATTRIBUTE_UNUSED, - void *data) -{ - virDomainSnapshotObjPtr snap = payload; - struct snap_remove *curr = data; - int err; - - if (snap->def->current) - curr->current = true; - err = qemuDomainSnapshotDiscard(curr->driver, curr->vm, snap, false, - curr->metadata_only); - if (err && !curr->err) - curr->err = err; -} - struct snap_reparent { struct qemud_driver *driver; const char *parent; @@ -9415,7 +9419,7 @@ static int qemuDomainSnapshotDelete(virDomainSnapshotPtr snapshot, rem.current = false; virDomainSnapshotForEachDescendant(&vm->snapshots, snap, - qemuDomainSnapshotDiscardDescendant, + qemuDomainSnapshotDiscardAll, &rem); if (rem.err < 0) goto endjob; -- 1.7.4.4