[PATCH 1/4] qemu: Generate shorter channel target paths

A <channel/> device is basically an UNIX socket into guest. Whatever is sent from the host, appears in the guest and vice versa. But because of that, the length of the path to the socket is important (underscored by fact that we derive the path from domain short name). But there are still cases where we might not fit into UNIX_PATH_MAX limit (usually 108 characters), because the path is derived also from other variables, e.g. XDG_CONFIG_HOME for session domains. There is one component though, that's needless: "/target/". Drop it. This is safe to do, because running domains have their path saved in status XML and even though paths are dropped on migration, they are not part of guest ABI and thus we are free to change them. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; --- libvirt.spec.in | 1 - src/qemu/qemu_conf.c | 6 +++--- src/qemu/qemu_domain.c | 9 ++++++--- .../qemuhotplug-qemu-agent-detach.xml | 2 +- .../qemuhotplug-base-live+qemu-agent-detach.xml | 2 +- .../qemuhotplug-base-live+qemu-agent.xml | 2 +- tests/qemuxml2argvdata/channel-unix-source-path.xml | 4 ++++ .../channel-unix-source-path-active.xml | 5 +++++ .../channel-unix-source-path-inactive.xml | 4 ++++ 9 files changed, 25 insertions(+), 10 deletions(-) diff --git a/libvirt.spec.in b/libvirt.spec.in index 1f77cd90b7..8aee709e42 100644 --- a/libvirt.spec.in +++ b/libvirt.spec.in @@ -2125,7 +2125,6 @@ exit 0 %ghost %dir %{_rundir}/libvirt/qemu/swtpm/ %dir %attr(0751, %{qemu_user}, %{qemu_group}) %{_localstatedir}/lib/libvirt/qemu/ %dir %attr(0751, %{qemu_user}, %{qemu_group}) %{_localstatedir}/lib/libvirt/qemu/channel/ -%dir %attr(0751, %{qemu_user}, %{qemu_group}) %{_localstatedir}/lib/libvirt/qemu/channel/target/ %dir %attr(0751, %{qemu_user}, %{qemu_group}) %{_localstatedir}/lib/libvirt/qemu/checkpoint/ %dir %attr(0751, %{qemu_user}, %{qemu_group}) %{_localstatedir}/lib/libvirt/qemu/dump/ %dir %attr(0751, %{qemu_user}, %{qemu_group}) %{_localstatedir}/lib/libvirt/qemu/nvram/ diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c index bd984448a3..532fe36be3 100644 --- a/src/qemu/qemu_conf.c +++ b/src/qemu/qemu_conf.c @@ -151,7 +151,7 @@ virQEMUDriverConfig *virQEMUDriverConfigNew(bool privileged, cfg->snapshotDir = g_strdup_printf("%s/snapshot", cfg->libDir); cfg->checkpointDir = g_strdup_printf("%s/checkpoint", cfg->libDir); cfg->autoDumpPath = g_strdup_printf("%s/dump", cfg->libDir); - cfg->channelTargetDir = g_strdup_printf("%s/channel/target", cfg->libDir); + cfg->channelTargetDir = g_strdup_printf("%s/channel", cfg->libDir); cfg->nvramDir = g_strdup_printf("%s/nvram", cfg->libDir); cfg->memoryBackingDir = g_strdup_printf("%s/ram", cfg->libDir); } else if (privileged) { @@ -173,7 +173,7 @@ virQEMUDriverConfig *virQEMUDriverConfigNew(bool privileged, cfg->snapshotDir = g_strdup_printf("%s/snapshot", cfg->libDir); cfg->checkpointDir = g_strdup_printf("%s/checkpoint", cfg->libDir); cfg->autoDumpPath = g_strdup_printf("%s/dump", cfg->libDir); - cfg->channelTargetDir = g_strdup_printf("%s/channel/target", cfg->libDir); + cfg->channelTargetDir = g_strdup_printf("%s/channel", cfg->libDir); cfg->nvramDir = g_strdup_printf("%s/nvram", cfg->libDir); cfg->memoryBackingDir = g_strdup_printf("%s/ram", cfg->libDir); cfg->swtpmStorageDir = g_strdup_printf("%s/lib/libvirt/swtpm", @@ -201,7 +201,7 @@ virQEMUDriverConfig *virQEMUDriverConfigNew(bool privileged, cfg->checkpointDir = g_strdup_printf("%s/qemu/checkpoint", cfg->configBaseDir); cfg->autoDumpPath = g_strdup_printf("%s/qemu/dump", cfg->configBaseDir); - cfg->channelTargetDir = g_strdup_printf("%s/qemu/channel/target", + cfg->channelTargetDir = g_strdup_printf("%s/qemu/channel", cfg->configBaseDir); cfg->nvramDir = g_strdup_printf("%s/qemu/nvram", cfg->configBaseDir); cfg->memoryBackingDir = g_strdup_printf("%s/qemu/ram", cfg->configBaseDir); diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 94587638c3..b4844351ba 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -1780,7 +1780,7 @@ qemuDomainSetPrivatePaths(virQEMUDriver *driver, priv->libDir = g_strdup_printf("%s/domain-%s", cfg->libDir, domname); if (!priv->channelTargetDir) - priv->channelTargetDir = g_strdup_printf("%s/domain-%s", + priv->channelTargetDir = g_strdup_printf("%s/%s", cfg->channelTargetDir, domname); return 0; @@ -5352,9 +5352,12 @@ qemuDomainDefaultNetModel(const virDomainDef *def, * libvirt 1.2.19 - 1.3.2: * {cfg->channelTargetDir}/domain-{dom-name}/{target-name} * - * libvirt 1.3.3 and newer: + * libvirt 1.3.3 - 9.4.0: * {cfg->channelTargetDir}/domain-{dom-id}-{short-dom-name}/{target-name} * + * libvirt 9.6.0 and newer: + * {cfg->channelTargetDir}/{dom-id}-{short-dom-name}/{target-name} + * * The unix socket path was stored in config XML until libvirt 1.3.0. * If someone specifies the same path as we generate, they shouldn't do it. * @@ -5379,7 +5382,7 @@ qemuDomainChrDefDropDefaultPath(virDomainChrDef *chr, cfg = virQEMUDriverGetConfig(driver); virBufferEscapeRegex(&buf, "^%s", cfg->channelTargetDir); - virBufferAddLit(&buf, "/([^/]+\\.)|(domain-[^/]+/)"); + virBufferAddLit(&buf, "/(target/)?([^/]+\\.)|(domain-[^/]+/)|([0-9]+-[^/]+/)"); virBufferEscapeRegex(&buf, "%s$", chr->target.name); regexp = virBufferContentAndReset(&buf); diff --git a/tests/qemuhotplugtestdevices/qemuhotplug-qemu-agent-detach.xml b/tests/qemuhotplugtestdevices/qemuhotplug-qemu-agent-detach.xml index 0c3c70a78e..2e5cbfe09c 100644 --- a/tests/qemuhotplugtestdevices/qemuhotplug-qemu-agent-detach.xml +++ b/tests/qemuhotplugtestdevices/qemuhotplug-qemu-agent-detach.xml @@ -1,5 +1,5 @@ <channel type='unix'> - <source mode='bind' path='/var/lib/libvirt/qemu/channel/target/domain-7-hotplug/org.qemu.guest_agent.0'/> + <source mode='bind' path='/var/lib/libvirt/qemu/channel/target/7-hotplug/org.qemu.guest_agent.0'/> <target type='virtio' name='org.qemu.guest_agent.0'/> <address type='virtio-serial' controller='0' bus='0' port='1'/> </channel> diff --git a/tests/qemuhotplugtestdomains/qemuhotplug-base-live+qemu-agent-detach.xml b/tests/qemuhotplugtestdomains/qemuhotplug-base-live+qemu-agent-detach.xml index 728af3391e..0469760737 100644 --- a/tests/qemuhotplugtestdomains/qemuhotplug-base-live+qemu-agent-detach.xml +++ b/tests/qemuhotplugtestdomains/qemuhotplug-base-live+qemu-agent-detach.xml @@ -39,7 +39,7 @@ <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> </controller> <channel type='unix'> - <source mode='bind' path='/var/lib/libvirt/qemu/channel/target/domain-7-hotplug/org.qemu.guest_agent.0'/> + <source mode='bind' path='/var/lib/libvirt/qemu/channel/target/7-hotplug/org.qemu.guest_agent.0'/> <target type='virtio' name='org.qemu.guest_agent.0'/> <alias name='channel0'/> <address type='virtio-serial' controller='0' bus='0' port='1'/> diff --git a/tests/qemuhotplugtestdomains/qemuhotplug-base-live+qemu-agent.xml b/tests/qemuhotplugtestdomains/qemuhotplug-base-live+qemu-agent.xml index 0e4c3907bf..8635a686e9 100644 --- a/tests/qemuhotplugtestdomains/qemuhotplug-base-live+qemu-agent.xml +++ b/tests/qemuhotplugtestdomains/qemuhotplug-base-live+qemu-agent.xml @@ -42,7 +42,7 @@ <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> </controller> <channel type='unix'> - <source mode='bind' path='/var/lib/libvirt/qemu/channel/target/domain-7-hotplug/org.qemu.guest_agent.0'/> + <source mode='bind' path='/var/lib/libvirt/qemu/channel/target/7-hotplug/org.qemu.guest_agent.0'/> <target type='virtio' name='org.qemu.guest_agent.0'/> <alias name='channel0'/> <address type='virtio-serial' controller='0' bus='0' port='1'/> diff --git a/tests/qemuxml2argvdata/channel-unix-source-path.xml b/tests/qemuxml2argvdata/channel-unix-source-path.xml index f24c636147..db0e99c3d1 100644 --- a/tests/qemuxml2argvdata/channel-unix-source-path.xml +++ b/tests/qemuxml2argvdata/channel-unix-source-path.xml @@ -24,6 +24,10 @@ <source mode='bind' path='/var/lib/libvirt/qemu/channel/target/QEMUGuest1/org.qemu.guest_agent.3'/> <target type='virtio' name='org.qemu.guest_agent.3'/> </channel> + <channel type='unix'> + <source mode='bind' path='/var/lib/libvirt/qemu/channel/1-QEMUGuest1/org.qemu.guest_agent.4'/> + <target type='virtio' name='org.qemu.guest_agent.4'/> + </channel> <memballoon model='none'/> </devices> </domain> diff --git a/tests/qemuxml2xmloutdata/channel-unix-source-path-active.xml b/tests/qemuxml2xmloutdata/channel-unix-source-path-active.xml index 0d6a0295f8..68835ceb15 100644 --- a/tests/qemuxml2xmloutdata/channel-unix-source-path-active.xml +++ b/tests/qemuxml2xmloutdata/channel-unix-source-path-active.xml @@ -41,6 +41,11 @@ <target type='virtio' name='org.qemu.guest_agent.3'/> <address type='virtio-serial' controller='0' bus='0' port='4'/> </channel> + <channel type='unix'> + <source mode='bind' path='/var/lib/libvirt/qemu/channel/1-QEMUGuest1/org.qemu.guest_agent.4'/> + <target type='virtio' name='org.qemu.guest_agent.4'/> + <address type='virtio-serial' controller='0' bus='0' port='5'/> + </channel> <input type='mouse' bus='ps2'/> <input type='keyboard' bus='ps2'/> <audio id='1' type='none'/> diff --git a/tests/qemuxml2xmloutdata/channel-unix-source-path-inactive.xml b/tests/qemuxml2xmloutdata/channel-unix-source-path-inactive.xml index d02ea52408..738c1184c0 100644 --- a/tests/qemuxml2xmloutdata/channel-unix-source-path-inactive.xml +++ b/tests/qemuxml2xmloutdata/channel-unix-source-path-inactive.xml @@ -38,6 +38,10 @@ <target type='virtio' name='org.qemu.guest_agent.3'/> <address type='virtio-serial' controller='0' bus='0' port='4'/> </channel> + <channel type='unix'> + <target type='virtio' name='org.qemu.guest_agent.4'/> + <address type='virtio-serial' controller='0' bus='0' port='5'/> + </channel> <input type='mouse' bus='ps2'/> <input type='keyboard' bus='ps2'/> <audio id='1' type='none'/> -- 2.41.0