Re: [libvirt] [PATCH v4 14/20] qemu: add vhost-user-gpu helper unit

From: Marc-André Lureau <marcandre.lureau(a)redhat.com&gt; Similar to the qemu_tpm.c, add a unit with a few functions to start/stop and setup the cgroup of the external vhost-user-gpu process. See function documentation. The vhost-user connection fd is set on qemuDomainVideoPrivate struct. Signed-off-by: Marc-André Lureau <marcandre.lureau(a)redhat.com&gt; --- src/qemu/Makefile.inc.am | 2 + src/qemu/qemu_domain.c | 5 +- src/qemu/qemu_domain.h | 2 +- src/qemu/qemu_vhost_user_gpu.c | 276 +++++++++++++++++++++++++++++++++ src/qemu/qemu_vhost_user_gpu.h | 49 ++++++ 5 files changed, 332 insertions(+), 2 deletions(-) create mode 100644 src/qemu/qemu_vhost_user_gpu.c create mode 100644 src/qemu/qemu_vhost_user_gpu.h diff --git a/src/qemu/Makefile.inc.am b/src/qemu/Makefile.inc.am index 449550e64b..8040bf9366 100644 --- a/src/qemu/Makefile.inc.am +++ b/src/qemu/Makefile.inc.am @@ -66,6 +66,8 @@ QEMU_DRIVER_SOURCES = \ qemu/qemu_tpm.h \ qemu/qemu_vhost_user.c \ qemu/qemu_vhost_user.h \ + qemu/qemu_vhost_user_gpu.c \ + qemu/qemu_vhost_user_gpu.h \ $(NULL) diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 9437694940..ab923aa917 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -1341,8 +1341,11 @@ qemuDomainVideoPrivateNew(void) static void -qemuDomainVideoPrivateDispose(void *obj ATTRIBUTE_UNUSED) +qemuDomainVideoPrivateDispose(void *obj) { + qemuDomainVideoPrivatePtr priv = obj; + + VIR_FORCE_CLOSE(priv->vhost_user_fd); } diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h index 89bd77b3c0..8afb4993d3 100644 --- a/src/qemu/qemu_domain.h +++ b/src/qemu/qemu_domain.h @@ -509,7 +509,7 @@ typedef qemuDomainVideoPrivate *qemuDomainVideoPrivatePtr; struct _qemuDomainVideoPrivate { virObject parent; - bool tmp_to_remove; + int vhost_user_fd; }; diff --git a/src/qemu/qemu_vhost_user_gpu.c b/src/qemu/qemu_vhost_user_gpu.c new file mode 100644 index 0000000000..b259b58434 --- /dev/null +++ b/src/qemu/qemu_vhost_user_gpu.c @@ -0,0 +1,276 @@ +/* + * qemu_vhost_user_gpu.c: QEMU vhost-user GPU support + * + * Copyright (C) 2019 Red Hat, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library. If not, see + * <http://www.gnu.org/licenses/>;. + */ + +#include <config.h> + +#include "qemu_vhost_user_gpu.h" +#include "qemu_vhost_user.h" +#include "qemu_extdevice.h" + +#include "conf/domain_conf.h" +#include "configmake.h" +#include "vircommand.h" +#include "viralloc.h" +#include "virlog.h" +#include "virutil.h" +#include "virfile.h" +#include "virstring.h" +#include "virtime.h" +#include "virpidfile.h" + +#define VIR_FROM_THIS VIR_FROM_NONE + +VIR_LOG_INIT("qemu.vhost_user_gpu"); + + +static char * +qemuVhostUserGPUCreatePidFilename(const char *stateDir, + const char *shortName, + const char *alias) +{ + VIR_AUTOFREE(char *) devicename = NULL; + + if (virAsprintf(&devicename, "%s-%s-vhost-user-gpu", shortName, alias) < 0) + return NULL; + + return virPidFileBuildPath(stateDir, devicename); +} + + +/* + * qemuVhostUserGPUGetPid: + * @binpath: path of executable associated with the pidfile + * @stateDir: the directory where vhost-user-gpu writes the pidfile into + * @shortName: short name of the domain + * @alias: video device alias + * @pid: pointer to pid + * + * Return -errno upon error, or zero on successful reading of the pidfile. + * If the PID was not still alive, zero will be returned, and @pid will be + * set to -1; + */ +static int +qemuVhostUserGPUGetPid(const char *binPath, + const char *stateDir, + const char *shortName, + const char *alias, + pid_t *pid) +{ + VIR_AUTOFREE(char *) pidfile = NULL; + + pidfile = qemuVhostUserGPUCreatePidFilename(stateDir, shortName, alias); + if (!pidfile) + return -ENOMEM; + + return virPidFileReadPathIfAlive(pidfile, pid, binPath); +} + + +int qemuExtVhostUserGPUPrepareDomain(virQEMUDriverPtr driver, + virDomainVideoDefPtr video) +{ + return qemuVhostUserFillDomainGPU(driver, video); +} + + +/* + * qemuExtVhostUserGPUStart: + * @driver: QEMU driver + * @vm: the VM domain + * @video: the video device + * + * Start the external vhost-user-gpu process: + * - open a socketpair for vhost-user communication + * - have the command line built + * - start the external process and sync with it before QEMU start + */ +int qemuExtVhostUserGPUStart(virQEMUDriverPtr driver, + virDomainObjPtr vm, + virDomainVideoDefPtr video) +{ + VIR_AUTOUNREF(virQEMUDriverConfigPtr) cfg = virQEMUDriverGetConfig(driver); + VIR_AUTOFREE(char *) shortname = NULL; + VIR_AUTOFREE(char *) pidfile = NULL; + VIR_AUTOPTR(virCommand) cmd = NULL; + int pair[2] = { -1, -1 }; + int cmdret = 0, rc; + int exitstatus = 0; + pid_t pid; + int ret = -1; + + shortname = virDomainDefGetShortName(vm->def); + if (!shortname) + goto error; + + /* stop any left-over for this VM */ + qemuExtVhostUserGPUStop(driver, vm, video); + + if (!(pidfile = qemuVhostUserGPUCreatePidFilename( + cfg->stateDir, shortname, video->info.alias))) + goto error; + + if (qemuSecuritySetSocketLabel(driver->securityManager, vm->def) < 0) + goto error; + + if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) < 0) { + virReportSystemError(errno, "%s", _("failed to create socket")); + goto error; + } + + if (qemuSecurityClearSocketLabel(driver->securityManager, vm->def) < 0) + goto error; + + cmd = virCommandNew(video->driver->vhost_user_binary); + if (!cmd) + goto error; + + virCommandClearCaps(cmd); + virCommandSetPidFile(cmd, pidfile); + virCommandDaemonize(cmd); + + if (qemuExtDeviceLogCommand(driver, vm, cmd, "vhost-user-gpu") < 0) + goto error; +

+ virCommandAddArgFormat(cmd, "--fd=%d", pair[0]); + virCommandPassFD(cmd, pair[0], VIR_COMMAND_PASS_FD_CLOSE_PARENT); + pair[0] = -1; + + if (video->accel) { + if (video->accel->accel3d) + virCommandAddArg(cmd, "--virgl"); + + if (video->accel->rendernode) + virCommandAddArgFormat(cmd, "--render-node=%s", video->accel->rendernode); + } + + if (qemuSecurityStartVhostUserGPU(driver, vm, cmd, + &exitstatus, &cmdret) < 0) + goto error; + + if (cmdret < 0 || exitstatus != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Could not start 'vhost-user-gpu'. exitstatus: %d"), exitstatus); + goto cleanup; + } +