On 09/26/2016 11:33 AM, Joao Martins wrote: The last sentence is not clear IMO and I'd like to improve it before pushing this series. What do you think of the below diff? Or feel free to propose something better :-). diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in index 129ba62..7008005 100644 --- a/docs/formatdomain.html.in +++ b/docs/formatdomain.html.in @@ -5981,12 +5981,12 @@ qemu-kvm -net nic,model=? /dev/null <code>connected</code> and <code>disconnected</code>. </dd> <dt><code>xen</code></dt> - <dd> Paravirtualized xen channel. Channel is exposed in the guest as a - xen console but identified with a name. The setup of the channel - depends to guest own rules and can live in a arbitrary path (for more - info, please see <a href="http://xenbits.xen.org/docs/unstable/misc/channel.txt">...>). + <dd> Paravirtualized Xen channel. Channel is exposed in the guest as a + Xen console but identified with a name. Setup and consumption of a Xen + channel depends on software and configuration in the guest + (for more info, please see <a href="http://xenbits.xen.org/docs/unstable/misc/channel.txt">...>). Channel source path semantics are the same as the virtio target type. - Although <code>state</code> attribute is not provided as xen channels + The <code>state</code> attribute is not supported since Xen channels lack the necessary probing mechanism. <span class="since">Since 2.3.0</span> </dd> Regards, Jim

And allow libxl to handle channel element which creates a Xen console visible to the guest as a low-bandwitdh communication channel. If type is PTY we also fetch the tty after boot using libxl_channel_getinfo to fetch the tty path. On socket case, we autogenerate a path if not specified in the XML. Path autogenerated is slightly different from qemu driver: qemu stores also on "channels/target" but it creates then a directory per domain with each channel target name. libxl doesn't appear to have a clear definition of private files associated with each domain, so for simplicity we do it slightly different. On qemu each autogenerated channel goes like: channels/target/<domain-name>/<target name> Whereas for libxl: channels/target/<domain-name>-<target name> Should note that if path is not specified it won't persist, existing only on live XML, unless user had initially specified it. Since support for libxl channels only came on Xen >= 4.5 we therefore need to conditionally compile it with LIBXL_HAVE_DEVICE_CHANNEL. After this patch and having a qemu guest agent: $ cat domain.xml | grep -a1 channel | head -n 5 | tail -n 4 <channel type='unix'> <source mode='bind' path='/tmp/channel'/> <target type='xen' name='org.qemu.guest_agent.0'/> </channel> $ virsh create domain.xml $ echo '{"execute":"guest-network-get-interfaces"}' | socat stdio,ignoreeof unix-connect:/tmp/channel {"execute":"guest-network-get-interfaces"} {"return": [{"name": "lo", "ip-addresses": [{"ip-address-type": "ipv4", "ip-address": "127.0.0.1", "prefix": 8}, {"ip-address-type": "ipv6", "ip-address": "::1", "prefix": 128}], "hardware-address": "00:00:00:00:00:00"}, {"name": "eth0", "ip-addresses": [{"ip-address-type": "ipv4", "ip-address": "10.100.0.6", "prefix": 24}, {"ip-address-type": "ipv6", "ip-address": "fe80::216:3eff:fe40:88eb", "prefix": 64}], "hardware-address": "00:16:3e:40:88:eb"}, {"name": "sit0"}]} Signed-off-by: Joao Martins <joao.m.martins(a)oracle.com&gt; --- Since v2: * Remove ret variable and do similar to other make functions. * Have channelDir passed as an argument instead of driver. Since v1: * Autogenerated paths, and updated commit message explaning it the different naming. Despite per domain name being slightly different, parent directory is same across both drivers. --- src/libxl/libxl_conf.c | 110 +++++++++++++++++++++++++++++++++++++++++++++++ src/libxl/libxl_conf.h | 3 ++ src/libxl/libxl_domain.c | 43 +++++++++++++++++- src/libxl/libxl_driver.c | 7 +++ 4 files changed, 162 insertions(+), 1 deletion(-) diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c index 92faa44..4c94d54 100644 --- a/src/libxl/libxl_conf.c +++ b/src/libxl/libxl_conf.c @@ -88,6 +88,7 @@ libxlDriverConfigDispose(void *obj) VIR_FREE(cfg->saveDir); VIR_FREE(cfg->autoDumpDir); VIR_FREE(cfg->lockManagerName); + VIR_FREE(cfg->channelDir); virFirmwareFreeList(cfg->firmwares, cfg->nfirmwares); } @@ -1348,6 +1349,8 @@ libxlDriverConfigNew(void) goto error; if (VIR_STRDUP(cfg->autoDumpDir, LIBXL_DUMP_DIR) < 0) goto error; + if (VIR_STRDUP(cfg->channelDir, LIBXL_CHANNEL_DIR) < 0) + goto error; if (virAsprintf(&log_file, "%s/libxl-driver.log", cfg->logDir) < 0) goto error; @@ -1499,6 +1502,107 @@ int libxlDriverConfigLoadFile(libxlDriverConfigPtr cfg, } +#ifdef LIBXL_HAVE_DEVICE_CHANNEL +static int +libxlPrepareChannel(virDomainChrDefPtr channel, + const char *channelDir, + const char *domainName) +{ + if (channel->targetType == VIR_DOMAIN_CHR_CHANNEL_TARGET_TYPE_XEN && + channel->source.type == VIR_DOMAIN_CHR_TYPE_UNIX && + !channel->source.data.nix.path) { + if (virAsprintf(&channel->source.data.nix.path, + "%s/%s-%s", channelDir, domainName, + channel->target.name ? channel->target.name + : "unknown.sock") < 0) + return -1; + + channel->source.data.nix.listen = true; + } + + return 0; +} + +static int +libxlMakeChannel(virDomainChrDefPtr l_channel, + libxl_device_channel *x_channel) +{ + libxl_device_channel_init(x_channel); + + if (l_channel->targetType != VIR_DOMAIN_CHR_CHANNEL_TARGET_TYPE_XEN) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("channel target type not supported")); + return -1; + } + + switch (l_channel->source.type) { + case VIR_DOMAIN_CHR_TYPE_PTY: + x_channel->connection = LIBXL_CHANNEL_CONNECTION_PTY; + break; + case VIR_DOMAIN_CHR_TYPE_UNIX: + x_channel->connection = LIBXL_CHANNEL_CONNECTION_SOCKET; + if (VIR_STRDUP(x_channel->u.socket.path, + l_channel->source.data.nix.path) < 0) + return -1; + break; + default: + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("channel source type not supported")); + break; + } + + if (!l_channel->target.name) { + virReportError(VIR_ERR_OPERATION_INVALID, "%s", + _("channel target name missing")); + return -1; + } + + if (VIR_STRDUP(x_channel->name, l_channel->target.name) < 0) + return -1; + + return 0; +} + +static int +libxlMakeChannelList(const char *channelDir, + virDomainDefPtr def, + libxl_domain_config *d_config) +{ + virDomainChrDefPtr *l_channels = def->channels; + size_t nchannels = def->nchannels; + libxl_device_channel *x_channels; + size_t i, nvchannels = 0; + + if (VIR_ALLOC_N(x_channels, nchannels) < 0) + return -1; + + for (i = 0; i < nchannels; i++) { + if (l_channels[i]->deviceType != VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL) + continue; + + if (libxlPrepareChannel(l_channels[i], channelDir, def->name) < 0) + goto error; + + if (libxlMakeChannel(l_channels[i], &x_channels[nvchannels]) < 0) + goto error; + + nvchannels++; + } + + VIR_SHRINK_N(x_channels, nchannels, nchannels - nvchannels); + d_config->channels = x_channels; + d_config->num_channels = nvchannels; + + return 0; + + error: + for (i = 0; i < nchannels; i++) + libxl_device_channel_dispose(&x_channels[i]); + VIR_FREE(x_channels); + return -1; +} +#endif + #ifdef LIBXL_HAVE_PVUSB int libxlMakeUSBController(virDomainControllerDefPtr controller, @@ -1839,6 +1943,7 @@ libxlDriverNodeGetInfo(libxlDriverPrivatePtr driver, virNodeInfoPtr info) int libxlBuildDomainConfig(virPortAllocatorPtr graphicsports, virDomainDefPtr def, + const char *channelDir, libxl_ctx *ctx, libxl_domain_config *d_config) { @@ -1873,6 +1978,11 @@ libxlBuildDomainConfig(virPortAllocatorPtr graphicsports, return -1; #endif +#ifdef LIBXL_HAVE_DEVICE_CHANNEL + if (libxlMakeChannelList(channelDir, def, d_config) < 0) + return -1; +#endif + /* * Now that any potential VFBs are defined, update the build info with * the data of the primary display. Some day libxl might implicitely do diff --git a/src/libxl/libxl_conf.h b/src/libxl/libxl_conf.h index ed5a3de..2d60fcc 100644 --- a/src/libxl/libxl_conf.h +++ b/src/libxl/libxl_conf.h @@ -57,6 +57,7 @@ # define LIBXL_LIB_DIR LOCALSTATEDIR "/lib/libvirt/libxl" # define LIBXL_SAVE_DIR LIBXL_LIB_DIR "/save" # define LIBXL_DUMP_DIR LIBXL_LIB_DIR "/dump" +# define LIBXL_CHANNEL_DIR LIBXL_LIB_DIR "/channel/target" # define LIBXL_BOOTLOADER_PATH "pygrub" @@ -98,6 +99,7 @@ struct _libxlDriverConfig { char *libDir; char *saveDir; char *autoDumpDir; + char *channelDir; virFirmwarePtr *firmwares; size_t nfirmwares; @@ -199,6 +201,7 @@ libxlCreateXMLConf(void); int libxlBuildDomainConfig(virPortAllocatorPtr graphicsports, virDomainDefPtr def, + const char *channelDir, libxl_ctx *ctx, libxl_domain_config *d_config); diff --git a/src/libxl/libxl_domain.c b/src/libxl/libxl_domain.c index bd04a05..77ce9fb 100644 --- a/src/libxl/libxl_domain.c +++ b/src/libxl/libxl_domain.c @@ -1061,6 +1061,42 @@ libxlDomainCreateIfaceNames(virDomainDefPtr def, libxl_domain_config *d_config) } } +#ifdef LIBXL_HAVE_DEVICE_CHANNEL +static void +libxlDomainCreateChannelPTY(virDomainDefPtr def, libxl_ctx *ctx) +{ + libxl_device_channel *x_channels; + virDomainChrDefPtr chr; + size_t i; + int nchannels; + + x_channels = libxl_device_channel_list(ctx, def->id, &nchannels); + if (!x_channels) + return; + + for (i = 0; i < def->nchannels; i++) { + libxl_channelinfo channelinfo; + int ret; + + chr = def->channels[i]; + if (chr->source.type != VIR_DOMAIN_CHR_TYPE_PTY) + continue; + + ret = libxl_device_channel_getinfo(ctx, def->id, &x_channels[i], + &channelinfo); + + if (!ret && channelinfo.u.pty.path && + channelinfo.u.pty.path != '\0') { + VIR_FREE(chr->source.data.file.path); + ignore_value(VIR_STRDUP(chr->source.data.file.path, + channelinfo.u.pty.path)); + } + } + + for (i = 0; i < nchannels; i++) + libxl_device_channel_dispose(&x_channels[i]); +} +#endif #ifdef LIBXL_HAVE_SRM_V2 # define LIBXL_DOMSTART_RESTORE_VER_ATTR /* empty */ @@ -1184,7 +1220,7 @@ libxlDomainStart(libxlDriverPrivatePtr driver, goto cleanup_dom; if (libxlBuildDomainConfig(driver->reservedGraphicsPorts, vm->def, - cfg->ctx, &d_config) < 0) + cfg->channelDir, cfg->ctx, &d_config) < 0) goto cleanup_dom; if (cfg->autoballoon && libxlDomainFreeMem(cfg->ctx, &d_config) < 0) @@ -1265,6 +1301,11 @@ libxlDomainStart(libxlDriverPrivatePtr driver, libxlDomainCreateIfaceNames(vm->def, &d_config); +#ifdef LIBXL_HAVE_DEVICE_CHANNEL + if (vm->def->nchannels > 0) + libxlDomainCreateChannelPTY(vm->def, cfg->ctx); +#endif + if ((dom_xml = virDomainDefFormat(vm->def, cfg->caps, 0)) == NULL) goto destroy_dom; diff --git a/src/libxl/libxl_driver.c b/src/libxl/libxl_driver.c index 54eee55..1adf4c5 100644 --- a/src/libxl/libxl_driver.c +++ b/src/libxl/libxl_driver.c @@ -718,6 +718,13 @@ libxlStateInitialize(bool privileged, virStrerror(errno, ebuf, sizeof(ebuf))); goto error; } + if (virFileMakePath(cfg->channelDir) < 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("failed to create channel dir '%s': %s"), + cfg->channelDir, + virStrerror(errno, ebuf, sizeof(ebuf))); + goto error; + } if (!(libxl_driver->lockManager = virLockManagerPluginNew(cfg->lockManagerName ? -- 2.1.4

On 09/26/2016 10:44 PM, Jim Fehlig wrote: Argh, sorry about this. In the rush of submitting this before beginning the freeze, I didn't remember to test the !LIBXL_HAVE_DEVICE_CHANNEL. Previous versions were good as it had driver being passed which was being also used to fetch reservedGraphicsPorts. Thanks, similar to src/network/bridge_driver.h you probably mean something like the diff below? It reuses the #ifdef LIBXL_HAVE_DEVICE_CHANNEL already in place in the patch . Though Your diff follow the general style with LIBXL_HAVE_* and potentially allows cleaner handling if we were to extend with more more arguments in libxlBuildDomainConfig or other function. FWIW, both approaches look good to me. diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c index 4c94d54..05745ee 100644 --- a/src/libxl/libxl_conf.c +++ b/src/libxl/libxl_conf.c @@ -1601,6 +1601,14 @@ libxlMakeChannelList(const char *channelDir, VIR_FREE(x_channels); return -1; } +#else +static int +libxlMakeChannelList(const char *channelDir ATTRIBUTE_UNUSED, + virDomainDefPtr def ATTRIBUTE_UNUSED, + libxl_domain_config *d_config ATTRIBUTE_UNUSED) +{ + return 0; +} #endif #ifdef LIBXL_HAVE_PVUSB @@ -1978,10 +1986,8 @@ libxlBuildDomainConfig(virPortAllocatorPtr graphicsports, return -1; #endif -#ifdef LIBXL_HAVE_DEVICE_CHANNEL if (libxlMakeChannelList(channelDir, def, d_config) < 0) return -1; -#endif /* * Now that any potential VFBs are defined, update the build info with

Add support for formating/parsing libxl channels. Syntax on xen libxl goes as following: channel=["connection=pty|socket,path=/path/to/socket,name=XXX",...] Signed-off-by: Joao Martins <joao.m.martins(a)oracle.com&gt; Acked-by: Jim Fehlig <jfehlig(a)suse.com&gt; --- Changes since v1: * Move path to UNIX case. --- src/xenconfig/xen_xl.c | 176 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 176 insertions(+) diff --git a/src/xenconfig/xen_xl.c b/src/xenconfig/xen_xl.c index 4615bfd..a06983e 100644 --- a/src/xenconfig/xen_xl.c +++ b/src/xenconfig/xen_xl.c @@ -685,6 +685,93 @@ xenParseXLUSB(virConfPtr conf, virDomainDefPtr def) return 0; } +static int +xenParseXLChannel(virConfPtr conf, virDomainDefPtr def) +{ + virConfValuePtr list = virConfGetValue(conf, "channel"); + virDomainChrDefPtr channel = NULL; + char *name = NULL; + char *path = NULL; + + if (list && list->type == VIR_CONF_LIST) { + list = list->list; + while (list) { + char type[10]; + char *key; + + if ((list->type != VIR_CONF_STRING) || (list->str == NULL)) + goto skipchannel; + + key = list->str; + while (key) { + char *data; + char *nextkey = strchr(key, ','); + + if (!(data = strchr(key, '='))) + goto skipchannel; + data++; + + if (STRPREFIX(key, "connection=")) { + int len = nextkey ? (nextkey - data) : sizeof(type) - 1; + if (virStrncpy(type, data, len, sizeof(type)) == NULL) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("connection %s too big"), data); + goto skipchannel; + } + } else if (STRPREFIX(key, "name=")) { + int len = nextkey ? (nextkey - data) : strlen(data); + VIR_FREE(name); + if (VIR_STRNDUP(name, data, len) < 0) + goto cleanup; + } else if (STRPREFIX(key, "path=")) { + int len = nextkey ? (nextkey - data) : strlen(data); + VIR_FREE(path); + if (VIR_STRNDUP(path, data, len) < 0) + goto cleanup; + } + + while (nextkey && (nextkey[0] == ',' || + nextkey[0] == ' ' || + nextkey[0] == '\t')) + nextkey++; + key = nextkey; + } + + if (!(channel = virDomainChrDefNew())) + goto cleanup; + + if (STRPREFIX(type, "socket")) { + channel->source.type = VIR_DOMAIN_CHR_TYPE_UNIX; + channel->source.data.nix.path = path; + channel->source.data.nix.listen = 1; + } else if (STRPREFIX(type, "pty")) { + channel->source.type = VIR_DOMAIN_CHR_TYPE_PTY; + VIR_FREE(path); + } else { + goto cleanup; + } + + channel->deviceType = VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL; + channel->targetType = VIR_DOMAIN_CHR_CHANNEL_TARGET_TYPE_XEN; + channel->target.name = name; + + if (VIR_APPEND_ELEMENT(def->channels, def->nchannels, channel) < 0) + goto cleanup; + + skipchannel: + list = list->next; + } + } + + return 0; + + cleanup: + virDomainChrDefFree(channel); + VIR_FREE(path); + VIR_FREE(name); + return -1; +} + virDomainDefPtr xenParseXL(virConfPtr conf, virCapsPtr caps, @@ -720,6 +807,9 @@ xenParseXL(virConfPtr conf, if (xenParseXLUSBController(conf, def) < 0) goto cleanup; + if (xenParseXLChannel(conf, def) < 0) + goto cleanup; + if (virDomainDefPostParse(def, caps, VIR_DOMAIN_DEF_PARSE_ABI_UPDATE, xmlopt, NULL) < 0) goto cleanup; @@ -1347,6 +1437,89 @@ xenFormatXLUSB(virConfPtr conf, return -1; } +static int +xenFormatXLChannel(virConfValuePtr list, virDomainChrDefPtr channel) +{ + virBuffer buf = VIR_BUFFER_INITIALIZER; + int sourceType = channel->source.type; + virConfValuePtr val, tmp; + + /* connection */ + virBufferAddLit(&buf, "connection="); + switch (sourceType) { + case VIR_DOMAIN_CHR_TYPE_PTY: + virBufferAddLit(&buf, "pty,"); + break; + case VIR_DOMAIN_CHR_TYPE_UNIX: + virBufferAddLit(&buf, "socket,"); + /* path */ + if (channel->source.data.nix.path) + virBufferAsprintf(&buf, "path=%s,", + channel->source.data.nix.path); + break; + default: + goto cleanup; + } + + /* name */ + virBufferAsprintf(&buf, "name=%s", channel->target.name); + + if (VIR_ALLOC(val) < 0) + goto cleanup; + + val->type = VIR_CONF_STRING; + val->str = virBufferContentAndReset(&buf); + tmp = list->list; + while (tmp && tmp->next) + tmp = tmp->next; + if (tmp) + tmp->next = val; + else + list->list = val; + return 0; + + cleanup: + virBufferFreeAndReset(&buf); + return -1; +} + +static int +xenFormatXLDomainChannels(virConfPtr conf, virDomainDefPtr def) +{ + virConfValuePtr channelVal = NULL; + size_t i; + + if (VIR_ALLOC(channelVal) < 0) + goto cleanup; + + channelVal->type = VIR_CONF_LIST; + channelVal->list = NULL; + + for (i = 0; i < def->nchannels; i++) { + virDomainChrDefPtr chr = def->channels[i]; + + if (chr->targetType != VIR_DOMAIN_CHR_CHANNEL_TARGET_TYPE_XEN) + continue; + + if (xenFormatXLChannel(channelVal, def->channels[i]) < 0) + goto cleanup; + } + + if (channelVal->list != NULL) { + int ret = virConfSetValue(conf, "channel", channelVal); + channelVal = NULL; + if (ret < 0) + goto cleanup; + } + + VIR_FREE(channelVal); + return 0; + + cleanup: + virConfFreeValue(channelVal); + return -1; +} + virConfPtr xenFormatXL(virDomainDefPtr def, virConnectPtr conn) { @@ -1376,6 +1549,9 @@ xenFormatXL(virDomainDefPtr def, virConnectPtr conn) if (xenFormatXLUSBController(conf, def) < 0) goto cleanup; + if (xenFormatXLDomainChannels(conf, def) < 0) + goto cleanup; + return conf; cleanup: -- 2.1.4