From: Roger Pau Monne Date: Mon, 7 Dec 2015 16:48:37 +0000 (+0100) Subject: libxl: add support for migrating HVM guests without a device model X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=18fcef8d62b28766e7b373a71d54bcf7578cea23;p=people%2Fjulieng%2Fxen-unstable.git libxl: add support for migrating HVM guests without a device model Only some minor libxl changes are needed in order to be able to migrate HVM guests without a device model, no hypervisor changes are needed. This change prevents sending the emulator context if the device model version is set to none. Signed-off-by: Roger Pau Monné Reviewed-by: Andrew Cooper Acked-by: Wei Liu Cc: Ian Jackson Cc: Ian Campbell Cc: Wei Liu --- diff --git a/tools/libxl/libxl_dom.c b/tools/libxl/libxl_dom.c index deb3ffa720..47971a96d3 100644 --- a/tools/libxl/libxl_dom.c +++ b/tools/libxl/libxl_dom.c @@ -1316,6 +1316,9 @@ void libxl__domain_suspend_common_switch_qemu_logdirty case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN: domain_suspend_switch_qemu_xen_logdirty(domid, enable, shs); break; + case LIBXL_DEVICE_MODEL_VERSION_NONE: + libxl__xc_domain_saverestore_async_callback_done(egc, shs, 0); + break; default: LOG(ERROR,"logdirty switch failed" ", no valid device model version found, abandoning suspend"); diff --git a/tools/libxl/libxl_dom_suspend.c b/tools/libxl/libxl_dom_suspend.c index 4cc01ad0fa..3313ad1ce4 100644 --- a/tools/libxl/libxl_dom_suspend.c +++ b/tools/libxl/libxl_dom_suspend.c @@ -43,6 +43,8 @@ int libxl__domain_suspend_device_model(libxl__gc *gc, if (ret) unlink(filename); break; + case LIBXL_DEVICE_MODEL_VERSION_NONE: + break; default: return ERROR_INVAL; } diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h index 15731a84a3..a556a38a42 100644 --- a/tools/libxl/libxl_internal.h +++ b/tools/libxl/libxl_internal.h @@ -3039,6 +3039,9 @@ struct libxl__stream_write_state { libxl__datacopier_state dc; sws_record_done_cb record_done_callback; + /* Cache device model version. */ + libxl_device_model_version device_model_version; + /* Only used when constructing EMULATOR records. */ libxl__datacopier_state emu_dc; libxl__carefd *emu_carefd; diff --git a/tools/libxl/libxl_stream_read.c b/tools/libxl/libxl_stream_read.c index 4ec29da9ab..258dec4c83 100644 --- a/tools/libxl/libxl_stream_read.c +++ b/tools/libxl/libxl_stream_read.c @@ -539,6 +539,14 @@ static bool process_record(libxl__egc *egc, break; case REC_TYPE_EMULATOR_XENSTORE_DATA: + if (dcs->guest_config->b_info.device_model_version == + LIBXL_DEVICE_MODEL_VERSION_NONE) { + rc = ERROR_FAIL; + LOG(ERROR, + "Received a xenstore emulator record when none was expected"); + goto err; + } + if (rec->hdr.length < sizeof(libxl__sr_emulator_hdr)) { rc = ERROR_FAIL; LOG(ERROR, @@ -560,6 +568,14 @@ static bool process_record(libxl__egc *egc, break; case REC_TYPE_EMULATOR_CONTEXT: + if (dcs->guest_config->b_info.device_model_version == + LIBXL_DEVICE_MODEL_VERSION_NONE) { + rc = ERROR_FAIL; + LOG(ERROR, + "Received an emulator context record when none was expected"); + goto err; + } + write_emulator_blob(egc, stream, rec); break; diff --git a/tools/libxl/libxl_stream_write.c b/tools/libxl/libxl_stream_write.c index 52a60d7726..80d9208062 100644 --- a/tools/libxl/libxl_stream_write.c +++ b/tools/libxl/libxl_stream_write.c @@ -167,6 +167,8 @@ static void setup_emulator_write(libxl__egc *egc, void *body, sws_record_done_cb cb) { + assert(stream->emu_sub_hdr.id != EMULATOR_UNKNOWN); + assert(stream->device_model_version != LIBXL_DEVICE_MODEL_VERSION_NONE); setup_generic_write(egc, stream, what, hdr, emu_hdr, body, cb); } @@ -207,6 +209,7 @@ void libxl__stream_write_init(libxl__stream_write_state *stream) FILLZERO(stream->emu_rec_hdr); FILLZERO(stream->emu_sub_hdr); stream->emu_body = NULL; + stream->device_model_version = LIBXL_DEVICE_MODEL_VERSION_UNKNOWN; } void libxl__stream_write_start(libxl__egc *egc, @@ -223,7 +226,9 @@ void libxl__stream_write_start(libxl__egc *egc, stream->running = true; if (dss->type == LIBXL_DOMAIN_TYPE_HVM) { - switch (libxl__device_model_version_running(gc, dss->domid)) { + stream->device_model_version = + libxl__device_model_version_running(gc, dss->domid); + switch (stream->device_model_version) { case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL: stream->emu_sub_hdr.id = EMULATOR_QEMU_TRADITIONAL; break; @@ -232,6 +237,10 @@ void libxl__stream_write_start(libxl__egc *egc, stream->emu_sub_hdr.id = EMULATOR_QEMU_UPSTREAM; break; + case LIBXL_DEVICE_MODEL_VERSION_NONE: + stream->emu_sub_hdr.id = EMULATOR_UNKNOWN; + break; + default: rc = ERROR_FAIL; LOG(ERROR, "Unknown emulator for HVM domain"); @@ -359,6 +368,11 @@ static void write_emulator_xenstore_record(libxl__egc *egc, char *buf = NULL; uint32_t len = 0; + if (stream->device_model_version == LIBXL_DEVICE_MODEL_VERSION_NONE) { + emulator_xenstore_record_done(egc, stream); + return; + } + rc = libxl__save_emulator_xenstore_data(dss, &buf, &len); if (rc) goto err; @@ -410,6 +424,11 @@ static void write_emulator_context_record(libxl__egc *egc, assert(dss->type == LIBXL_DOMAIN_TYPE_HVM); + if (stream->device_model_version == LIBXL_DEVICE_MODEL_VERSION_NONE) { + emulator_context_record_done(egc, stream); + return; + } + /* Convenience aliases */ const char *const filename = dss->dm_savefile;