Re: [libvirt] [PATCH 6/6] qemu: Use fd: protocol for migration

By opening a connection to remote qemu process ourselves and passing the socket to qemu we get much better errors than just "migration failed" when the connection is opened by qemu. --- src/qemu/qemu_migration.c | 128 ++++++++++++++++++++++++++++++++++----------- 1 files changed, 98 insertions(+), 30 deletions(-) diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c index c29ea9e..537e57e 100644 --- a/src/qemu/qemu_migration.c +++ b/src/qemu/qemu_migration.c @@ -1269,6 +1269,7 @@ cleanup: enum qemuMigrationDestinationType { MIGRATION_DEST_HOST, MIGRATION_DEST_UNIX, + MIGRATION_DEST_FD, }; enum qemuMigrationForwardType { @@ -1287,9 +1288,14 @@ struct _qemuMigrationSpec { } host; struct { - const char *file; + char *file; int sock; } unics; /* this sucks but "unix" is a macro defined to 1 */ + + struct { + int qemu; + int local; + } fd; } dest; enum qemuMigrationForwardType fwdType; @@ -1472,6 +1478,14 @@ qemuMigrationRun(struct qemud_driver *driver, ret = qemuMonitorMigrateToCommand(priv->mon, migrate_flags, args); } break; + + case MIGRATION_DEST_FD: + if (spec->fwdType != MIGRATION_FWD_DIRECT) + fd = spec->dest.fd.local; + ret = qemuMonitorMigrateToFd(priv->mon, migrate_flags, + spec->dest.fd.qemu); + VIR_FORCE_CLOSE(spec->dest.fd.qemu);

+ break; } qemuDomainObjExitMonitorWithDriver(driver, vm); if (ret < 0) @@ -1568,9 +1582,11 @@ static int doNativeMigrate(struct qemud_driver *driver, unsigned int flags, unsigned long resource) { + qemuDomainObjPrivatePtr priv = vm->privateData; xmlURIPtr uribits = NULL; - int ret; + int ret = -1; qemuMigrationSpec spec; + char *tmp = NULL; VIR_DEBUG("driver=%p, vm=%p, uri=%s, cookiein=%s, cookieinlen=%d, " "cookieout=%p, cookieoutlen=%p, flags=%x, resource=%lu", @@ -1579,13 +1595,12 @@ static int doNativeMigrate(struct qemud_driver *driver, if (STRPREFIX(uri, "tcp:") && !STRPREFIX(uri, "tcp://")) { /* HACK: source host generates bogus URIs, so fix them up */ - char *tmpuri; - if (virAsprintf(&tmpuri, "tcp://%s", uri + strlen("tcp:")) < 0) { + if (virAsprintf(&tmp, "tcp://%s", uri + strlen("tcp:")) < 0) { virReportOOMError(); return -1; } - uribits = xmlParseURI(tmpuri); - VIR_FREE(tmpuri); + uribits = xmlParseURI(tmp); + VIR_FREE(tmp); } else { uribits = xmlParseURI(uri); } @@ -1595,13 +1610,38 @@ static int doNativeMigrate(struct qemud_driver *driver, return -1; } - spec.destType = MIGRATION_DEST_HOST; - spec.dest.host.name = uribits->server; - spec.dest.host.port = uribits->port; spec.fwdType = MIGRATION_FWD_DIRECT; + if (qemuCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATE_QEMU_FD)) { + virNetSocketPtr sock; + + spec.destType = MIGRATION_DEST_FD; + spec.dest.fd.qemu = -1; + + if (virAsprintf(&tmp, "%d", uribits->port) < 0) { + virReportOOMError(); + goto cleanup; + } + if (virNetSocketNewConnectTCP(uribits->server, tmp, &sock) == 0) { + spec.dest.fd.qemu = virNetSocketDupFD(sock, true); + virNetSocketFree(sock); + } + if (spec.dest.fd.qemu == -1) + goto cleanup; + } else { + spec.destType = MIGRATION_DEST_HOST; + spec.dest.host.name = uribits->server; + spec.dest.host.port = uribits->port; + } + ret = qemuMigrationRun(driver, vm, cookiein, cookieinlen, cookieout, cookieoutlen, flags, resource, &spec); + +cleanup: + if (spec.destType == MIGRATION_DEST_FD) + VIR_FORCE_CLOSE(spec.dest.fd.qemu); + + VIR_FREE(tmp); xmlFreeURI(uribits); return ret; @@ -1619,7 +1659,6 @@ static int doTunnelMigrate(struct qemud_driver *driver, unsigned long resource) { qemuDomainObjPrivatePtr priv = vm->privateData; - char *unixfile = NULL; virNetSocketPtr sock = NULL; int ret = -1; qemuMigrationSpec spec; @@ -1629,36 +1668,65 @@ static int doTunnelMigrate(struct qemud_driver *driver, driver, vm, st, NULLSTR(cookiein), cookieinlen, cookieout, cookieoutlen, flags, resource); - if (!qemuCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATE_QEMU_UNIX) && + if (!qemuCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATE_QEMU_FD) && + !qemuCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATE_QEMU_UNIX) && !qemuCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATE_QEMU_EXEC)) { - qemuReportError(VIR_ERR_OPERATION_FAILED, - "%s", _("Source qemu is too old to support tunnelled migration")); - goto cleanup; - } - - if (virAsprintf(&unixfile, "%s/qemu.tunnelmigrate.src.%s", - driver->libDir, vm->def->name) < 0) { - virReportOOMError(); - goto cleanup; + qemuReportError(VIR_ERR_OPERATION_FAILED, "%s", + _("Source qemu is too old to support tunnelled migration")); + return -1; } - if (virNetSocketNewListenUNIX(unixfile, 0700, - driver->user, driver->group, &sock) < 0 || - virNetSocketListen(sock, 1) < 0) - goto cleanup; - - spec.destType = MIGRATION_DEST_UNIX; - spec.dest.unics.file = unixfile; - spec.dest.unics.sock = virNetSocketGetFD(sock); spec.fwdType = MIGRATION_FWD_STREAM; spec.fwd.stream = st; + if (qemuCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATE_QEMU_FD)) { + int fds[2]; + + spec.destType = MIGRATION_DEST_FD; + spec.dest.fd.qemu = -1; + spec.dest.fd.local = -1; + + if (pipe(fds) == 0) { + spec.dest.fd.qemu = fds[1]; + spec.dest.fd.local = fds[0]; + } + if (spec.dest.fd.qemu == -1 || + virSetCloseExec(spec.dest.fd.qemu) < 0 || + virSetCloseExec(spec.dest.fd.local) < 0) { + virReportSystemError(errno, "%s", + _("cannot create pipe for tunnelled migration")); + goto cleanup; + } + } else { + spec.destType = MIGRATION_DEST_UNIX; + spec.dest.unics.sock = -1; + spec.dest.unics.file = NULL; + + if (virAsprintf(&spec.dest.unics.file, "%s/qemu.tunnelmigrate.src.%s", + driver->libDir, vm->def->name) < 0) { + virReportOOMError(); + goto cleanup; + } + + if (virNetSocketNewListenUNIX(spec.dest.unics.file, 0700, driver->user, + driver->group, &sock) < 0 || + virNetSocketListen(sock, 1) < 0) + goto cleanup; + + spec.dest.unics.sock = virNetSocketGetFD(sock); + } + ret = qemuMigrationRun(driver, vm, cookiein, cookieinlen, cookieout, cookieoutlen, flags, resource, &spec); cleanup: - virNetSocketFree(sock); - VIR_FREE(unixfile); + if (spec.destType == MIGRATION_DEST_FD) { + VIR_FORCE_CLOSE(spec.dest.fd.qemu); + VIR_FORCE_CLOSE(spec.dest.fd.local); + } else { + virNetSocketFree(sock); + VIR_FREE(spec.dest.unics.file); + } return ret; }