Re: [libvirt] [PATCH v1 14/19] qemu: Allow hotplug of vhost-scsi device

Adjust the device string that is built for vhost-scsi devices so that it can be invoked from hotplug. >From the QEMU command line, the file descriptors are expect to be numeric only. However, for hotplug, the file descriptors are expected to begin with at least one alphabetic character else this error occurs: # virsh attach-device guest_0001 ~/vhost.xml error: Failed to attach device from /root/vhost.xml error: internal error: unable to execute QEMU command 'getfd': Parameter 'fdname' expects a name not starting with a digit We also close the file descriptor in this case, so that shutting down the guest cleans up the host cgroup entries and allows future guests to use vhost-scsi devices. (Otherwise the guest will silently end.) Signed-off-by: Eric Farman <farman(a)linux.vnet.ibm.com&gt; Reviewed-by: Bjoern Walk <bwalk(a)linux.vnet.ibm.com&gt; Reviewed-by: Boris Fiuczynski <fiuczy(a)linux.vnet.ibm.com&gt; --- src/qemu/qemu_command.c | 34 ++++++++++++++++++++++++++++---- src/qemu/qemu_command.h | 3 ++- src/qemu/qemu_hotplug.c | 52 ++++++++++++++++++++++++++++++++++++++----------- src/qemu/qemu_monitor.c | 21 ++++++++++++++++++++ src/qemu/qemu_monitor.h | 4 ++++ 5 files changed, 98 insertions(+), 16 deletions(-) diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 31b30a4..6677c28 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -4536,12 +4536,14 @@ char * qemuBuildSCSIVhostHostdevDevStr(const virDomainDef *def, virDomainHostdevDefPtr dev, virQEMUCapsPtr qemuCaps, - virCommandPtr cmd) + virCommandPtr cmd, + qemuMonitorPtr mon) { size_t i; virBuffer buf = VIR_BUFFER_INITIALIZER; virDomainHostdevSubsysSCSIPtr scsisrc = &dev->source.subsys.u.scsi; virDomainHostdevSubsysSCSIVhostPtr vhostsrc = &scsisrc->u.vhost; + char **vhostfdName = NULL; int *vhostfd = NULL; size_t vhostfdSize = 1; @@ -4551,6 +4553,9 @@ qemuBuildSCSIVhostHostdevDevStr(const virDomainDef *def, goto cleanup; } + if ((cmd && mon) || (!cmd && !mon)) + goto cleanup; + if (ARCH_IS_S390(def->os.arch)) virBufferAddLit(&buf, "vhost-scsi-ccw"); else @@ -4563,18 +4568,28 @@ qemuBuildSCSIVhostHostdevDevStr(const virDomainDef *def, memset(vhostfd, -1, sizeof(*vhostfd) * vhostfdSize); + if (VIR_ALLOC_N(vhostfdName, vhostfdSize) < 0) + goto cleanup; + if (virSCSIOpenVhost(vhostfd, &vhostfdSize) < 0) goto cleanup; + if (mon) { + if (qemuMonitorAttachVhostSCSI(mon, vhostfd, vhostfdName, vhostfdSize) < 0) + goto cleanup; + } + for (i = 0; i < vhostfdSize; i++) { if (cmd) { virCommandPassFD(cmd, vhostfd[i], VIR_COMMAND_PASS_FD_CLOSE_PARENT); + if (virAsprintf(&vhostfdName[i], "%d", vhostfd[i]) < 0) + goto cleanup; } } if (vhostfdSize == 1) { - virBufferAsprintf(&buf, ",vhostfd=%d", vhostfd[0]); + virBufferAsprintf(&buf, ",vhostfd=%s", vhostfdName[0]); } else { /* FIXME if 'vhostfds' became a valid vhost-scsi property in QEMU */ goto cleanup; @@ -4582,13 +4597,24 @@ qemuBuildSCSIVhostHostdevDevStr(const virDomainDef *def, virBufferAsprintf(&buf, ",id=%s", dev->info->alias); + for (i = 0; vhostfd && i < vhostfdSize; i++) { + if (mon) + VIR_FORCE_CLOSE(vhostfd[i]); + if (vhostfdName) + VIR_FREE(vhostfdName[i]); + } VIR_FREE(vhostfd); + VIR_FREE(vhostfdName); return virBufferContentAndReset(&buf); cleanup: - for (i = 0; vhostfd && i < vhostfdSize; i++) + for (i = 0; vhostfd && i < vhostfdSize; i++) { VIR_FORCE_CLOSE(vhostfd[i]); + if (vhostfdName) + VIR_FREE(vhostfdName[i]); + } VIR_FREE(vhostfd); + VIR_FREE(vhostfdName); virBufferFreeAndReset(&buf); return NULL; }

@@ -5017,7 +5043,7 @@ qemuBuildHostdevCommandLine(virCommandPtr cmd, if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_SCSI_GENERIC)) { if (hostdev->source.subsys.u.scsi.protocol == VIR_DOMAIN_HOSTDEV_SCSI_PROTOCOL_TYPE_VHOST) { virCommandAddArg(cmd, "-device"); - if (!(devstr = qemuBuildSCSIVhostHostdevDevStr(def, hostdev, qemuCaps, cmd))) + if (!(devstr = qemuBuildSCSIVhostHostdevDevStr(def, hostdev, qemuCaps, cmd, NULL))) return -1; } else { char *drvstr; diff --git a/src/qemu/qemu_command.h b/src/qemu/qemu_command.h index 5c2dcb0..d5a6256 100644 --- a/src/qemu/qemu_command.h +++ b/src/qemu/qemu_command.h @@ -163,7 +163,8 @@ char * qemuBuildSCSIVhostHostdevDevStr(const virDomainDef *def, virDomainHostdevDefPtr dev, virQEMUCapsPtr qemuCaps, - virCommandPtr cmd); + virCommandPtr cmd, + qemuMonitorPtr mon); char *qemuBuildRedirdevDevStr(const virDomainDef *def, virDomainRedirdevDefPtr dev, diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c index 02f7017..77e436c 100644 --- a/src/qemu/qemu_hotplug.c +++ b/src/qemu/qemu_hotplug.c @@ -2003,16 +2003,29 @@ qemuDomainAttachHostSCSIDevice(virConnectPtr conn, return -1; } - /* Let's make sure the disk has a controller defined and loaded before - * trying to add it. The controller used by the disk must exist before a - * qemu command line string is generated. - * - * Ensure that the given controller and all controllers with a smaller index - * exist; there must not be any missing index in between. - */ - for (i = 0; i <= hostdev->info->addr.drive.controller; i++) { - if (!qemuDomainFindOrCreateSCSIDiskController(driver, vm, i)) - return -1; + if (hostdev->source.subsys.u.scsi.protocol != VIR_DOMAIN_HOSTDEV_SCSI_PROTOCOL_TYPE_VHOST) { + /* Let's make sure the disk has a controller defined and loaded before + * trying to add it. The controller used by the disk must exist before a + * qemu command line string is generated. + * + * Ensure that the given controller and all controllers with a smaller index + * exist; there must not be any missing index in between. + */ + for (i = 0; i <= hostdev->info->addr.drive.controller; i++) { + if (!qemuDomainFindOrCreateSCSIDiskController(driver, vm, i)) + return -1; + } + } else { + if (hostdev->info->type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE) { + if (qemuDomainMachineIsS390CCW(vm->def) && + virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_VIRTIO_CCW)) + hostdev->info->type = VIR_DOMAIN_DEVICE_ADDRESS_TYPE_CCW; + } + if (hostdev->info->type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_CCW) { + if (virDomainCCWAddressAssign(hostdev->info, priv->ccwaddrs,

+ !hostdev->info->addr.ccw.assigned) < 0) + goto cleanup; + } } if (qemuHostdevPrepareSCSIDevices(driver, vm->def->name, @@ -2023,6 +2036,11 @@ qemuDomainAttachHostSCSIDevice(virConnectPtr conn, virReportError(VIR_ERR_INTERNAL_ERROR, _("Unable to prepare scsi hostdev for iSCSI: %s"), iscsisrc->path); + } else if (scsisrc->protocol == VIR_DOMAIN_HOSTDEV_SCSI_PROTOCOL_TYPE_VHOST) { + virDomainHostdevSubsysSCSIVhostPtr vhostsrc = &scsisrc->u.vhost; + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Unable to prepare scsi hostdev for vhost: %s"), + vhostsrc->wwpn); } else { virDomainHostdevSubsysSCSIHostPtr scsihostsrc = &scsisrc->u.host; virReportError(VIR_ERR_INTERNAL_ERROR, @@ -2048,7 +2066,19 @@ qemuDomainAttachHostSCSIDevice(virConnectPtr conn, if (qemuDomainSecretHostdevPrepare(conn, priv, hostdev) < 0) goto cleanup; - if (hostdev->source.subsys.u.scsi.protocol != VIR_DOMAIN_HOSTDEV_SCSI_PROTOCOL_TYPE_VHOST) { + if (hostdev->source.subsys.u.scsi.protocol == VIR_DOMAIN_HOSTDEV_SCSI_PROTOCOL_TYPE_VHOST) { + qemuDomainObjEnterMonitor(driver, vm); + if (!(devstr = qemuBuildSCSIVhostHostdevDevStr(vm->def, hostdev, priv->qemuCaps, NULL, priv->mon))) + goto cleanup; + + if (VIR_REALLOC_N(vm->def->hostdevs, vm->def->nhostdevs + 1) < 0) + goto cleanup; + + if ((ret = qemuMonitorAddDevice(priv->mon, devstr)) < 0) { + ignore_value(qemuDomainObjExitMonitor(driver, vm) < 0); + goto cleanup; + } + } else { if (!(drvstr = qemuBuildSCSIHostdevDrvStr(hostdev))) goto cleanup; diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c index 098e654..51c3531 100644 --- a/src/qemu/qemu_monitor.c +++ b/src/qemu/qemu_monitor.c @@ -2689,6 +2689,27 @@ qemuMonitorGetChardevInfo(qemuMonitorPtr mon, } +int +qemuMonitorAttachVhostSCSI(qemuMonitorPtr mon, + int *vhostfd, + char **vhostfdName, + int vhostfdSize) +{ + size_t i; + + QEMU_CHECK_MONITOR(mon); + + for (i = 0; i < vhostfdSize; i++) { + if (virAsprintf(&vhostfdName[i], "vhost-%d", vhostfd[i]) < 0) + return -1; + if (qemuMonitorSendFileHandle(mon, vhostfdName[i], vhostfd[i]) < 0) + return -1; + } + + return 0; +}

+ + /** * qemuMonitorDriveDel: * @mon: monitor object diff --git a/src/qemu/qemu_monitor.h b/src/qemu/qemu_monitor.h index cb4cca8..67050c5 100644 --- a/src/qemu/qemu_monitor.h +++ b/src/qemu/qemu_monitor.h @@ -679,6 +679,10 @@ void qemuMonitorChardevInfoFree(void *data, const void *name); int qemuMonitorGetChardevInfo(qemuMonitorPtr mon, virHashTablePtr *retinfo); +int qemuMonitorAttachVhostSCSI(qemuMonitorPtr mon, + int *vhostfd, + char **vhostfdName, + int vhostfdSize); int qemuMonitorAttachPCIDiskController(qemuMonitorPtr mon, const char *bus, virPCIDeviceAddress *guestAddr);