From 950c46f1a4fd8beb208fd03c8bb14b022a027ccf Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?J=C3=A1n=20Tomko?= Date: Tue, 22 May 2018 15:52:52 +0200 Subject: [PATCH] util: create virvsock.c MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit A file for vsock-related helper functions. virVsockSetGuestCid to set an already-known CID, virVsockAcquireGuestCid that will use the first available CID https://bugzilla.redhat.com/show_bug.cgi?id=1291851 Signed-off-by: Ján Tomko --- configure.ac | 8 +++ src/libvirt_private.syms | 5 ++ src/util/Makefile.inc.am | 2 + src/util/virvsock.c | 105 +++++++++++++++++++++++++++++++++++++++ src/util/virvsock.h | 29 +++++++++++ 5 files changed, 149 insertions(+) create mode 100644 src/util/virvsock.c create mode 100644 src/util/virvsock.h diff --git a/configure.ac b/configure.ac index cc005ea9e8..b869a17afe 100644 --- a/configure.ac +++ b/configure.ac @@ -641,6 +641,14 @@ if test "$with_linux" = "yes"; then [[#include ]]) fi +dnl +dnl check for VHOST_VSOCK_SET_GUEST_CID +dnl +if test "$with_linux" = "yes"; then + AC_CHECK_DECLS([VHOST_VSOCK_SET_GUEST_CID], [], [], + [[#include ]]) +fi + dnl Allow perl/python overrides AC_PATH_PROGS([PYTHON], [python3 python2 python]) if test -z "$PYTHON"; then diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 682c9f15f3..6001635916 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -3122,6 +3122,11 @@ virVHBAManageVport; virVHBAPathExists; +# util/virvsock.h +virVsockAcquireGuestCid; +virVsockSetGuestCid; + + # util/virxml.h virXMLCheckIllegalChars; virXMLChildElementCount; diff --git a/src/util/Makefile.inc.am b/src/util/Makefile.inc.am index ec8745da7e..a22265606c 100644 --- a/src/util/Makefile.inc.am +++ b/src/util/Makefile.inc.am @@ -204,6 +204,8 @@ UTIL_SOURCES = \ util/viruuid.h \ util/virvhba.c \ util/virvhba.h \ + util/virvsock.c \ + util/virvsock.h \ util/virxdrdefs.h \ util/virxml.c \ util/virxml.h \ diff --git a/src/util/virvsock.c b/src/util/virvsock.c new file mode 100644 index 0000000000..ebb5182619 --- /dev/null +++ b/src/util/virvsock.c @@ -0,0 +1,105 @@ +/* + * 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 + * . + * + */ + +#include + +#include + +#if HAVE_DECL_VHOST_VSOCK_SET_GUEST_CID +# include +#endif + +#include "virvsock.h" + +#include "virerror.h" +#include "virlog.h" + + +#define VIR_FROM_THIS VIR_FROM_NONE + +VIR_LOG_INIT("util.vsock"); + +#if HAVE_DECL_VHOST_VSOCK_SET_GUEST_CID +static int +virVsockSetGuestCidQuiet(int fd, + unsigned int guest_cid) +{ + uint64_t val = guest_cid; + + return ioctl(fd, VHOST_VSOCK_SET_GUEST_CID, &val); +} + +#else +static int +virVsockSetGuestCidQuiet(int fd ATTRIBUTE_UNUSED, + unsigned int guest_cid ATTRIBUTE_UNUSED) +{ + errno = ENOSYS; + return -1; +} +#endif + + +/** + * virVsockSetGuestCid: + * @fd: file descriptor of a vsock interface + * @guest_cid: guest CID to be set + * + * Wrapper for VHOST_VSOCK_SET_GUEST_CID ioctl. + * Returns: 0 on success, -1 on error. + */ +int +virVsockSetGuestCid(int fd, + unsigned int guest_cid) +{ + if (virVsockSetGuestCidQuiet(fd, guest_cid) < 0) { + virReportSystemError(errno, "%s", + _("failed to set guest cid")); + return -1; + } + + return 0; +} + +#define VIR_VSOCK_GUEST_CID_MIN 3 + +/** + * virVsockAcquireGuestCid: + * @fd: file descriptor of a vsock interface + * @guest_cid: where to store the guest CID + * + * Iterates over usable CIDs until a free one is found. + * Returns: 0 on success, with the acquired CID stored in guest_cid + * -1 on error. + */ +int +virVsockAcquireGuestCid(int fd, + unsigned int *guest_cid) +{ + unsigned int cid = VIR_VSOCK_GUEST_CID_MIN; + + for (; virVsockSetGuestCidQuiet(fd, cid) < 0; cid++) { + if (errno != EADDRINUSE) { + virReportSystemError(errno, "%s", + _("failed to acquire guest cid")); + return -1; + } + } + *guest_cid = cid; + + return 0; +} diff --git a/src/util/virvsock.h b/src/util/virvsock.h new file mode 100644 index 0000000000..080a322420 --- /dev/null +++ b/src/util/virvsock.h @@ -0,0 +1,29 @@ +/* + * virvsock.h - vsock related util functions + * + * 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 + * . + */ + +#ifndef __VIR_VSOCK_H__ +# define __VIR_VSOCK_H__ + +int +virVsockSetGuestCid(int fd, + unsigned int guest_cid); + +int +virVsockAcquireGuestCid(int fd, + unsigned int *guest_cid); +#endif /* __VIR_VSOCK_H__ */