Re: [libvirt PATCHv3 10/12] qemu: add code for handling virtiofsd

Start virtiofsd for each <filesystem> device using it. Pre-create the socket for communication with QEMU and pass it to virtiofsd. Note that virtiofsd needs to run as root.

+int +qemuVirtioFSStart(virLogManagerPtr logManager, + virQEMUDriverPtr driver, + virDomainObjPtr vm, + virDomainFSDefPtr fs) +{ + g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver); + g_autoptr(virCommand) cmd = NULL; + g_autofree char *socket_path = NULL; + g_autofree char *pidfile = NULL; + g_autofree char *logpath = NULL; + pid_t pid = (pid_t) -1; + VIR_AUTOCLOSE fd = -1; + VIR_AUTOCLOSE logfd = -1; + int ret = -1; + int rc;

+ + if (!(pidfile = qemuVirtioFSCreatePidFilename(cfg, vm->def, fs->info.alias))) + goto cleanup; + + if (!(socket_path = qemuVirtioFSCreateSocketFilename(vm, fs->info.alias))) + goto cleanup; + + if ((fd = qemuVirtioFSOpenChardev(driver, vm, socket_path)) < 0) + goto cleanup; + + logpath = qemuVirtioFSCreateLogFilename(cfg, vm->def, fs->info.alias); + + if (cfg->stdioLogD) { + if ((logfd = virLogManagerDomainOpenLogFile(logManager, + "qemu", + vm->def->uuid, + vm->def->name, + logpath, + 0, + NULL, NULL)) < 0) + goto cleanup; + } else { + if ((logfd = open(logpath, O_WRONLY | O_CREAT | O_APPEND, S_IRUSR | S_IWUSR)) < 0) { + virReportSystemError(errno, _("failed to create logfile %s"), + logpath); + goto cleanup; + } + if (virSetCloseExec(logfd) < 0) { + virReportSystemError(errno, _("failed to set close-on-exec flag on %s"), + logpath); + goto error; + } + } + + if (!(cmd = qemuVirtioFSBuildCommandLine(cfg, fs, &fd))) + goto cleanup; + + virCommandSetPidFile(cmd, pidfile); + virCommandSetOutputFD(cmd, &logfd); + virCommandSetErrorFD(cmd, &logfd); + virCommandNonblockingFDs(cmd); + virCommandDaemonize(cmd);

+ + if (qemuExtDeviceLogCommand(driver, vm, cmd, "virtiofsd") < 0) + goto cleanup; + + rc = virCommandRun(cmd, NULL); + logfd = -1; + + if (rc < 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("Could not start 'virtiofsd'")); + goto error; + } + + rc = virPidFileReadPath(pidfile, &pid); + if (rc < 0) { + virReportSystemError(-rc, + _("Unable to read virtiofsd pidfile '%s'"), + pidfile); + goto error; + } + + if (virProcessKill(pid, 0) != 0) { + virReportSystemError(errno, "%s", + _("virtiofsd died unexpectedly")); + goto error; + } + + QEMU_DOMAIN_FS_PRIVATE(fs)->vhostuser_fs_sock = g_steal_pointer(&socket_path); + ret = 0; + + cleanup: + if (socket_path) + unlink(socket_path); + return ret; + + error: + if (pid != -1) + virProcessKillPainfully(pid, true); + if (pidfile) + unlink(pidfile); + goto cleanup; +}