Re: [libvirt] [PATCH v1 10/19] qemu: Add vhost-scsi string for -device parameter

Open /dev/vhost-scsi, and record the resulting file descriptor, so that the guest has access to the host device outside of the libvirt daemon. Pass this information, along with data parsed from the XML file, to build a device string for the qemu command line. That device string will be for either a vhost-scsi-ccw device in the case of an s390 machine, or vhost-scsi-pci for any others. Signed-off-by: Eric Farman <farman(a)linux.vnet.ibm.com&gt; Reviewed-by: Boris Fiuczynski <fiuczy(a)linux.vnet.ibm.com&gt; --- src/libvirt_private.syms | 1 + src/qemu/qemu_command.c | 67 +++++++++++++++++++++++++++++++++++++++++++++++- src/qemu/qemu_command.h | 5 ++++ src/util/virscsi.c | 26 +++++++++++++++++++ src/util/virscsi.h | 1 + 5 files changed, 99 insertions(+), 1 deletion(-) diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 9396c4e..b91c7a8 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -2253,6 +2253,7 @@ virSCSIDeviceListNew; virSCSIDeviceListSteal; virSCSIDeviceNew; virSCSIDeviceSetUsedBy; +virSCSIOpenVhost; # util/virseclabel.h diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index dd15ff8..31b30a4 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -4533,6 +4533,67 @@ qemuBuildSCSIiSCSIHostdevDrvStr(virDomainHostdevDefPtr dev) } char * +qemuBuildSCSIVhostHostdevDevStr(const virDomainDef *def, + virDomainHostdevDefPtr dev, + virQEMUCapsPtr qemuCaps, + virCommandPtr cmd) +{ + size_t i; + virBuffer buf = VIR_BUFFER_INITIALIZER; + virDomainHostdevSubsysSCSIPtr scsisrc = &dev->source.subsys.u.scsi; + virDomainHostdevSubsysSCSIVhostPtr vhostsrc = &scsisrc->u.vhost; + int *vhostfd = NULL; + size_t vhostfdSize = 1; + + if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_VHOST_SCSI)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("This QEMU doesn't support vhost-scsi devices")); + goto cleanup; + } + + if (ARCH_IS_S390(def->os.arch)) + virBufferAddLit(&buf, "vhost-scsi-ccw"); + else + virBufferAddLit(&buf, "vhost-scsi-pci"); + + virBufferAsprintf(&buf, ",wwpn=%s", vhostsrc->wwpn); + + if (VIR_ALLOC_N(vhostfd, vhostfdSize) < 0) + goto cleanup; + + memset(vhostfd, -1, sizeof(*vhostfd) * vhostfdSize); + + if (virSCSIOpenVhost(vhostfd, &vhostfdSize) < 0) + goto cleanup; + + for (i = 0; i < vhostfdSize; i++) { + if (cmd) {

+ virCommandPassFD(cmd, vhostfd[i], + VIR_COMMAND_PASS_FD_CLOSE_PARENT); + } + } + + if (vhostfdSize == 1) { + virBufferAsprintf(&buf, ",vhostfd=%d", vhostfd[0]); + } else { + /* FIXME if 'vhostfds' became a valid vhost-scsi property in QEMU */ + goto cleanup;

+ } + + virBufferAsprintf(&buf, ",id=%s", dev->info->alias);

+ + VIR_FREE(vhostfd); + return virBufferContentAndReset(&buf); + + cleanup: + for (i = 0; vhostfd && i < vhostfdSize; i++) + VIR_FORCE_CLOSE(vhostfd[i]); + VIR_FREE(vhostfd); + virBufferFreeAndReset(&buf); + return NULL; +}