[libvirt PATCHv5 12/15] 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. https://bugzilla.redhat.com/show_bug.cgi?id=1694166 Introduced by QEMU commit a43efa34c7d7b628cbf1ec0fe60043e5c91043ea Signed-off-by: Ján Tomko <jtomko(a)redhat.com&gt; --- po/POTFILES.in | 1 + src/qemu/Makefile.inc.am | 2 + src/qemu/qemu_domain.c | 5 +- src/qemu/qemu_domain.h | 2 +- src/qemu/qemu_extdevice.c | 20 ++- src/qemu/qemu_virtiofs.c | 301 ++++++++++++++++++++++++++++++++++++++ src/qemu/qemu_virtiofs.h | 37 +++++ tests/qemuxml2argvtest.c | 11 ++ 8 files changed, 376 insertions(+), 3 deletions(-) create mode 100644 src/qemu/qemu_virtiofs.c create mode 100644 src/qemu/qemu_virtiofs.h diff --git a/po/POTFILES.in b/po/POTFILES.in index fe361204bb..982f2ebc36 100644 --- a/po/POTFILES.in +++ b/po/POTFILES.in @@ -172,6 +172,7 @@ @SRCDIR(a)/src/qemu/qemu_tpm.c @SRCDIR(a)/src/qemu/qemu_vhost_user.c @SRCDIR(a)/src/qemu/qemu_vhost_user_gpu.c +@SRCDIR(a)/src/qemu/qemu_virtiofs.c @SRCDIR(a)/src/remote/remote_daemon.c @SRCDIR(a)/src/remote/remote_daemon_config.c @SRCDIR(a)/src/remote/remote_daemon_dispatch.c diff --git a/src/qemu/Makefile.inc.am b/src/qemu/Makefile.inc.am index 94a333f855..51cd79879d 100644 --- a/src/qemu/Makefile.inc.am +++ b/src/qemu/Makefile.inc.am @@ -67,6 +67,8 @@ QEMU_DRIVER_SOURCES = \ qemu/qemu_vhost_user.h \ qemu/qemu_vhost_user_gpu.c \ qemu/qemu_vhost_user_gpu.h \ + qemu/qemu_virtiofs.c \ + qemu/qemu_virtiofs.h \ qemu/qemu_checkpoint.c \ qemu/qemu_checkpoint.h \ qemu/qemu_backup.c \ diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index d85c089dce..33c2158eb5 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -1433,8 +1433,11 @@ qemuDomainFSPrivateNew(void) static void -qemuDomainFSPrivateDispose(void *obj G_GNUC_UNUSED) +qemuDomainFSPrivateDispose(void *obj) { + qemuDomainFSPrivatePtr priv = obj; + + g_free(priv->vhostuser_fs_sock); } static virClassPtr qemuDomainVideoPrivateClass; diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h index f8fb48f2ff..476056c73f 100644 --- a/src/qemu/qemu_domain.h +++ b/src/qemu/qemu_domain.h @@ -568,7 +568,7 @@ typedef qemuDomainFSPrivate *qemuDomainFSPrivatePtr; struct _qemuDomainFSPrivate { virObject parent; - int dummy; + char *vhostuser_fs_sock; }; diff --git a/src/qemu/qemu_extdevice.c b/src/qemu/qemu_extdevice.c index bb73787b8d..bfa770f45a 100644 --- a/src/qemu/qemu_extdevice.c +++ b/src/qemu/qemu_extdevice.c @@ -20,11 +20,13 @@ #include <config.h> +#include "qemu_command.h" #include "qemu_extdevice.h" #include "qemu_vhost_user_gpu.h" #include "qemu_domain.h" #include "qemu_tpm.h" #include "qemu_slirp.h" +#include "qemu_virtiofs.h" #include "viralloc.h" #include "virlog.h" @@ -153,7 +155,7 @@ qemuExtDevicesCleanupHost(virQEMUDriverPtr driver, int qemuExtDevicesStart(virQEMUDriverPtr driver, virDomainObjPtr vm, - virLogManagerPtr logManager G_GNUC_UNUSED, + virLogManagerPtr logManager, bool incomingMigration) { virDomainDefPtr def = vm->def; @@ -183,6 +185,15 @@ qemuExtDevicesStart(virQEMUDriverPtr driver, return -1; } + for (i = 0; i < def->nfss; i++) { + virDomainFSDefPtr fs = def->fss[i]; + + if (fs->fsdriver == VIR_DOMAIN_FS_DRIVER_TYPE_VIRTIOFS) { + if (qemuVirtioFSStart(logManager, driver, vm, fs) < 0) + return -1; + } + } + return 0; } @@ -214,6 +225,13 @@ qemuExtDevicesStop(virQEMUDriverPtr driver, if (slirp) qemuSlirpStop(slirp, vm, driver, net, false); } + + for (i = 0; i < def->nfss; i++) { + virDomainFSDefPtr fs = def->fss[i]; + + if (fs->fsdriver == VIR_DOMAIN_FS_DRIVER_TYPE_VIRTIOFS) + qemuVirtioFSStop(driver, vm, fs); + } } diff --git a/src/qemu/qemu_virtiofs.c b/src/qemu/qemu_virtiofs.c new file mode 100644 index 0000000000..09ab2cef27 --- /dev/null +++ b/src/qemu/qemu_virtiofs.c @@ -0,0 +1,301 @@ +/* + * qemu_virtiofs.c: virtiofs support + * + * 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 <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> + +#include "logging/log_manager.h" +#include "virlog.h" +#include "qemu_command.h" +#include "qemu_conf.h" +#include "qemu_extdevice.h" +#include "qemu_security.h" +#include "qemu_virtiofs.h" +#include "virpidfile.h" +#include "virqemu.h" +#include "virutil.h" + +#define VIR_FROM_THIS VIR_FROM_QEMU + + +char * +qemuVirtioFSCreatePidFilename(virDomainObjPtr vm, + const char *alias) +{ + qemuDomainObjPrivatePtr priv = vm->privateData; + g_autofree char *shortName = NULL; + g_autofree char *name = NULL; + + if (!(shortName = virDomainDefGetShortName(vm->def))) + return NULL; + + name = g_strdup_printf("%s-%s-virtiofsd", shortName, alias); + + return virPidFileBuildPath(priv->libDir, name); +} + + +char * +qemuVirtioFSCreateSocketFilename(virDomainObjPtr vm, + const char *alias) +{ + qemuDomainObjPrivatePtr priv = vm->privateData; + + return virFileBuildPath(priv->libDir, alias, "-virtiofsd.sock"); +} + + +static char * +qemuVirtioFSCreateLogFilename(virQEMUDriverConfigPtr cfg, + const virDomainDef *def, + const char *alias) +{ + g_autofree char *name = NULL; + + name = g_strdup_printf("%s-%s", def->name, alias); + + return virFileBuildPath(cfg->logDir, name, "-virtiofsd.log"); +} + + +static int +qemuVirtioFSOpenChardev(virQEMUDriverPtr driver, + virDomainObjPtr vm, + const char *socket_path) +{ + virDomainChrSourceDefPtr chrdev = virDomainChrSourceDefNew(NULL); + virDomainChrDef chr = { .source = chrdev }; + VIR_AUTOCLOSE fd = -1; + int ret = -1; + + chrdev->type = VIR_DOMAIN_CHR_TYPE_UNIX; + chrdev->data.nix.listen = true; + chrdev->data.nix.path = g_strdup(socket_path); + + if (qemuSecuritySetDaemonSocketLabel(driver->securityManager, vm->def) < 0) + goto cleanup; + fd = qemuOpenChrChardevUNIXSocket(chrdev); + if (fd < 0) { + ignore_value(qemuSecurityClearSocketLabel(driver->securityManager, vm->def)); + goto cleanup; + } + if (qemuSecurityClearSocketLabel(driver->securityManager, vm->def) < 0) + goto cleanup; + + if (qemuSecuritySetChardevLabel(driver, vm, &chr) < 0) + goto cleanup; + + ret = fd; + fd = -1; + + cleanup: + virObjectUnref(chrdev); + return ret; +} + + +static virCommandPtr +qemuVirtioFSBuildCommandLine(virQEMUDriverConfigPtr cfg, + virDomainFSDefPtr fs, + int *fd) +{ + g_autoptr(virCommand) cmd = NULL; + g_auto(virBuffer) opts = VIR_BUFFER_INITIALIZER; + + if (!(cmd = virCommandNew(fs->binary))) + return NULL; + + virCommandAddArgFormat(cmd, "--fd=%d", *fd); + virCommandPassFD(cmd, *fd, VIR_COMMAND_PASS_FD_CLOSE_PARENT); + *fd = -1; + + virCommandAddArg(cmd, "-o"); + virBufferAddLit(&opts, "source="); + virQEMUBuildBufferEscapeComma(&opts, fs->src->path); + if (fs->cache) + virBufferAsprintf(&opts, ",cache=%s", virDomainFSCacheModeTypeToString(fs->cache)); + + if (fs->xattr == VIR_TRISTATE_SWITCH_ON) + virBufferAddLit(&opts, ",xattr"); + else if (fs->xattr == VIR_TRISTATE_SWITCH_OFF) + virBufferAddLit(&opts, ",no_xattr"); + + if (fs->flock == VIR_TRISTATE_SWITCH_ON) + virBufferAddLit(&opts, ",flock"); + else if (fs->flock == VIR_TRISTATE_SWITCH_OFF) + virBufferAddLit(&opts, ",no_flock"); + + if (fs->posix_lock == VIR_TRISTATE_SWITCH_ON) + virBufferAddLit(&opts, ",posix_lock"); + else if (fs->posix_lock == VIR_TRISTATE_SWITCH_OFF) + virBufferAddLit(&opts, ",no_posix_lock"); + + virCommandAddArgBuffer(cmd, &opts); + if (cfg->virtiofsdDebug) + virCommandAddArg(cmd, "-d"); + + return g_steal_pointer(&cmd); +} + +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 (!virFileExists(fs->src->path)) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("the virtiofs export directory '%s' does not exist"), + fs->src->path); + return -1; + } + + if (!(pidfile = qemuVirtioFSCreatePidFilename(vm, 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; + + /* so far only running as root is supported */ + virCommandSetUID(cmd, 0); + virCommandSetGID(cmd, 0); + + 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); + + 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; +} + + +void +qemuVirtioFSStop(virQEMUDriverPtr driver G_GNUC_UNUSED, + virDomainObjPtr vm, + virDomainFSDefPtr fs) +{ + g_autofree char *pidfile = NULL; + virErrorPtr orig_err; + pid_t pid = -1; + int rc; + + virErrorPreserveLast(&orig_err); + + if (!(pidfile = qemuVirtioFSCreatePidFilename(vm, fs->info.alias))) + goto cleanup; + + rc = virPidFileReadPathIfAlive(pidfile, &pid, NULL); + if (rc >= 0 && pid != (pid_t) -1) + virProcessKillPainfully(pid, true); + + if (unlink(pidfile) < 0 && + errno != ENOENT) { + virReportSystemError(errno, + _("Unable to remove stale pidfile %s"), + pidfile); + } + + if (QEMU_DOMAIN_FS_PRIVATE(fs)->vhostuser_fs_sock) + unlink(QEMU_DOMAIN_FS_PRIVATE(fs)->vhostuser_fs_sock); + + cleanup: + virErrorRestore(&orig_err); +} diff --git a/src/qemu/qemu_virtiofs.h b/src/qemu/qemu_virtiofs.h new file mode 100644 index 0000000000..b2f0c57d0c --- /dev/null +++ b/src/qemu/qemu_virtiofs.h @@ -0,0 +1,37 @@ +/* + * qemu_virtiofs.h: virtiofs support + * + * 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/>;. + */ + +#pragma once + + +char * +qemuVirtioFSCreatePidFilename(virDomainObjPtr vm, + const char *alias); +char * +qemuVirtioFSCreateSocketFilename(virDomainObjPtr vm, + const char *alias); + +int +qemuVirtioFSStart(virLogManagerPtr logManager, + virQEMUDriverPtr driver, + virDomainObjPtr vm, + virDomainFSDefPtr fs); +void +qemuVirtioFSStop(virQEMUDriverPtr driver, + virDomainObjPtr vm, + virDomainFSDefPtr fs); diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c index 038fd97580..abbc273889 100644 --- a/tests/qemuxml2argvtest.c +++ b/tests/qemuxml2argvtest.c @@ -496,6 +496,17 @@ testCompareXMLToArgv(const void *data) } } + for (i = 0; i < vm->def->nfss; i++) { + virDomainFSDefPtr fs = vm->def->fss[i]; + char *s; + + if (fs->fsdriver != VIR_DOMAIN_FS_DRIVER_TYPE_VIRTIOFS) + continue; + + s = g_strdup_printf("/tmp/lib/domain--1-guest/fs%zu.vhost-fs.sock", i); + QEMU_DOMAIN_FS_PRIVATE(fs)->vhostuser_fs_sock = s; + } + if (vm->def->vsock) { virDomainVsockDefPtr vsock = vm->def->vsock; qemuDomainVsockPrivatePtr vsockPriv = -- 2.24.1