From 1e925d1c171e8eb7893f4f6b2aa948a66742b784 Mon Sep 17 00:00:00 2001 From: Peter Krempa Date: Thu, 5 May 2022 16:34:52 +0200 Subject: [PATCH] qemu_fd: Don't rely on fdset id allocation by qemu MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If we use our own fdset ID when hot-adding a fdset we can vastly simplify our internals. As a stop-gap when a fdset would be added behind libvirt's back we'll validated that the fdset to be added is not yet used. Signed-off-by: Peter Krempa Reviewed-by: Jonathon Jongsma Reviewed-by: Ján Tomko --- src/qemu/qemu_fd.c | 69 ++++++++++++++++--------------------- src/qemu/qemu_fd.h | 3 -- tests/qemuhotplugtest.c | 1 + tests/qemumonitorjsontest.c | 7 ---- 4 files changed, 30 insertions(+), 50 deletions(-) diff --git a/src/qemu/qemu_fd.c b/src/qemu/qemu_fd.c index 84e9d2bfdf..88039e8596 100644 --- a/src/qemu/qemu_fd.c +++ b/src/qemu/qemu_fd.c @@ -111,8 +111,12 @@ qemuFDPassNew(const char *prefix, fdpass->prefix = g_strdup(prefix); fdpass->useFDSet = true; - if (priv) + if (priv) { fdpass->fdSetID = qemuDomainFDSetIDNew(priv); + fdpass->path = g_strdup_printf("/dev/fdset/%u", fdpass->fdSetID); + } else { + fdpass->path = g_strdup_printf("/dev/fdset/monitor-fake"); + } return fdpass; } @@ -171,6 +175,11 @@ qemuFDPassAddFD(qemuFDPass *fdpass, newfd.opaque = g_strdup_printf("%s%s", fdpass->prefix, NULLSTR_EMPTY(suffix)); + if (!fdpass->useFDSet) { + g_free(fdpass->path); + fdpass->path = g_strdup(newfd.opaque); + } + VIR_APPEND_ELEMENT(fdpass->fds, fdpass->nfds, newfd); } @@ -207,10 +216,10 @@ qemuFDPassTransferCommand(qemuFDPass *fdpass, fdpass->fds[i].opaque); virCommandAddArgList(cmd, "-add-fd", arg, NULL); - - fdpass->path = g_strdup_printf("/dev/fdset/%u", fdpass->fdSetID); } else { - fdpass->path = g_strdup_printf("%u", fdpass->fds[i].fd); + /* for monitor use the older FD passing needs the FD number */ + g_free(fdpass->path); + fdpass->path = g_strdup_printf("%d", fdpass->fds[i].fd); } fdpass->fds[i].fd = -1; @@ -232,7 +241,6 @@ int qemuFDPassTransferMonitor(qemuFDPass *fdpass, qemuMonitor *mon) { - int fdsetid = -1; size_t i; if (!fdpass) @@ -240,6 +248,21 @@ qemuFDPassTransferMonitor(qemuFDPass *fdpass, if (qemuFDPassValidate(fdpass) < 0) return -1; + if (fdpass->useFDSet) { + g_autoptr(qemuMonitorFdsets) fdsets = NULL; + + if (qemuMonitorQueryFdsets(mon, &fdsets) < 0) + return -1; + + for (i = 0; i < fdsets->nfdsets; i++) { + if (fdsets->fdsets[i].id == fdpass->fdSetID) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("fdset '%u' is already in use by qemu"), + fdpass->fdSetID); + return -1; + } + } + } for (i = 0; i < fdpass->nfds; i++) { if (fdpass->useFDSet) { @@ -247,22 +270,15 @@ qemuFDPassTransferMonitor(qemuFDPass *fdpass, if (qemuMonitorAddFileHandleToSet(mon, fdpass->fds[i].fd, - fdsetid, + fdpass->fdSetID, fdpass->fds[i].opaque, &fdsetinfo) < 0) return -1; - - if (fdsetid == -1) { - fdpass->fdSetID = fdsetid = fdsetinfo.fdset; - fdpass->path = g_strdup_printf("/dev/fdset/%u", fdsetid); - } } else { if (qemuMonitorSendFileHandle(mon, fdpass->fds[i].opaque, fdpass->fds[i].fd) < 0) return -1; - - fdpass->path = g_strdup(fdpass->fds[i].opaque); } fdpass->passed = true; @@ -272,33 +288,6 @@ qemuFDPassTransferMonitor(qemuFDPass *fdpass, } -/** - * qemuFDPassTransferMonitorFake: - * @fdpass: The fd passing helper struct - * - * Simulate as if @fdpass was passed via monitor for callers which don't - * actually wish to test that code path. - */ -int -qemuFDPassTransferMonitorFake(qemuFDPass *fdpass) -{ - - if (!fdpass) - return 0; - - if (qemuFDPassValidate(fdpass) < 0) - return -1; - - if (fdpass->useFDSet) { - fdpass->path = g_strdup_printf("/dev/fdset/monitor-fake"); - } else { - fdpass->path = g_strdup(fdpass->fds[0].opaque); - } - - return 0; -} - - /** * qemuFDPassTransferMonitorRollback: * @fdpass: The fd passing helper struct diff --git a/src/qemu/qemu_fd.h b/src/qemu/qemu_fd.h index ef35daba8c..d078d4ce5d 100644 --- a/src/qemu/qemu_fd.h +++ b/src/qemu/qemu_fd.h @@ -47,9 +47,6 @@ int qemuFDPassTransferMonitor(qemuFDPass *fdpass, qemuMonitor *mon); -int -qemuFDPassTransferMonitorFake(qemuFDPass *fdpass); - void qemuFDPassTransferMonitorRollback(qemuFDPass *fdpass, qemuMonitor *mon); diff --git a/tests/qemuhotplugtest.c b/tests/qemuhotplugtest.c index 21302e0fce..fe8f0b58db 100644 --- a/tests/qemuhotplugtest.c +++ b/tests/qemuhotplugtest.c @@ -834,6 +834,7 @@ mymain(void) "device_del", QMP_DEVICE_DELETED("hostdev0") QMP_OK); DO_TEST_ATTACH("base-live", "interface-vdpa", false, true, + "query-fdsets", "{\"return\":[{\"fdset-id\":99999}]}", "add-fd", "{ \"return\": { \"fdset-id\": 1, \"fd\": 95 }}", "netdev_add", QMP_OK, "device_add", QMP_OK); DO_TEST_DETACH("base-live", "interface-vdpa", false, false, diff --git a/tests/qemumonitorjsontest.c b/tests/qemumonitorjsontest.c index e15c8533f6..c3ee771cbb 100644 --- a/tests/qemumonitorjsontest.c +++ b/tests/qemumonitorjsontest.c @@ -725,7 +725,6 @@ qemuMonitorJSONTestAttachChardev(virDomainXMLOption *xmlopt, { g_autoptr(virDomainChrSourceDef) chr = virDomainChrSourceDefNew(xmlopt); - qemuDomainChrSourcePrivate *charpriv = QEMU_DOMAIN_CHR_SOURCE_PRIVATE(chr); chr->data.file.path = g_strdup("/test/path"); @@ -743,12 +742,6 @@ qemuMonitorJSONTestAttachChardev(virDomainXMLOption *xmlopt, chrdev.source = chr; ignore_value(testQemuPrepareHostBackendChardevOne(&dev, chr, NULL)); - if (qemuFDPassTransferMonitorFake(charpriv->sourcefd) < 0) - ret = -1; - - if (qemuFDPassTransferMonitorFake(charpriv->logfd) < 0) - ret = -1; - CHECK("file", false, "{'id':'alias','backend':{'type':'file','data':{'out':'/dev/fdset/monitor-fake'," "'append':true,"