29 static void init_vp_index(struct vmbus_channel *channel);
46 	/* Fibre Channel */
170  * The rescinded channel may be blocked waiting for a response from the host;
173 static void vmbus_rescind_cleanup(struct vmbus_channel *channel)  in vmbus_rescind_cleanup()  argument
180 	channel->rescind = true;  in vmbus_rescind_cleanup()
184 		if (msginfo->waiting_channel == channel) {  in vmbus_rescind_cleanup()
202 static u16 hv_get_dev_type(const struct vmbus_channel *channel)  in hv_get_dev_type()  argument
204 	const guid_t *guid = &channel->offermsg.offer.if_type;  in hv_get_dev_type()
207 	if (is_hvsock_channel(channel) || is_unsupported_vmbus_devs(guid))  in hv_get_dev_type()
221  * @buf: Raw buffer channel data
222  * @buflen: Length of the raw buffer channel data.
351  * alloc_channel - Allocate and initialize a vmbus channel object
355 	struct vmbus_channel *channel;  in alloc_channel()  local
357 	channel = kzalloc(sizeof(*channel), GFP_ATOMIC);  in alloc_channel()
358 	if (!channel)  in alloc_channel()
361 	spin_lock_init(&channel->sched_lock);  in alloc_channel()
362 	init_completion(&channel->rescind_event);  in alloc_channel()
364 	INIT_LIST_HEAD(&channel->sc_list);  in alloc_channel()
366 	tasklet_init(&channel->callback_event,  in alloc_channel()
367 		     vmbus_on_event, (unsigned long)channel);  in alloc_channel()
369 	hv_ringbuffer_pre_init(channel);  in alloc_channel()
371 	return channel;  in alloc_channel()
375  * free_channel - Release the resources used by the vmbus channel object
377 static void free_channel(struct vmbus_channel *channel)  in free_channel()  argument
379 	tasklet_kill(&channel->callback_event);  in free_channel()
380 	vmbus_remove_channel_attr_group(channel);  in free_channel()
382 	kobject_put(&channel->kobj);  in free_channel()
385 void vmbus_channel_map_relid(struct vmbus_channel *channel)  in vmbus_channel_map_relid()  argument
387 	if (WARN_ON(channel->offermsg.child_relid >= MAX_CHANNEL_RELIDS))  in vmbus_channel_map_relid()
390 	 * The mapping of the channel's relid is visible from the CPUs that  in vmbus_channel_map_relid()
398 	 *      channel's ring buffer is allocated/initialized and the  in vmbus_channel_map_relid()
399 	 *      OPENCHANNEL message for the channel is sent in vmbus_open().  in vmbus_channel_map_relid()
400 	 *      Hyper-V won't start sending the interrupts for the channel  in vmbus_channel_map_relid()
403 	 *      that vmbus_chan_sched() must find the channel's relid in  in vmbus_channel_map_relid()
404 	 *      recv_int_page before retrieving the channel pointer from the  in vmbus_channel_map_relid()
415 		vmbus_connection.channels[channel->offermsg.child_relid],  in vmbus_channel_map_relid()
416 		channel);  in vmbus_channel_map_relid()
419 void vmbus_channel_unmap_relid(struct vmbus_channel *channel)  in vmbus_channel_unmap_relid()  argument
421 	if (WARN_ON(channel->offermsg.child_relid >= MAX_CHANNEL_RELIDS))  in vmbus_channel_unmap_relid()
424 		vmbus_connection.channels[channel->offermsg.child_relid],  in vmbus_channel_unmap_relid()
442 void hv_process_channel_removal(struct vmbus_channel *channel)  in hv_process_channel_removal()  argument
445 	BUG_ON(!channel->rescind);  in hv_process_channel_removal()
451 	WARN_ON(channel->offermsg.child_relid == INVALID_RELID &&  in hv_process_channel_removal()
452 		!is_hvsock_channel(channel));  in hv_process_channel_removal()
455 	 * Upon suspend, an in-use hv_sock channel is removed from the array of  in hv_process_channel_removal()
457 	 * user-space application destroys the channel, it's unnecessary and  in hv_process_channel_removal()
458 	 * unsafe to remove the channel from the array of channels.  See also  in hv_process_channel_removal()
461 	if (channel->offermsg.child_relid != INVALID_RELID)  in hv_process_channel_removal()
462 		vmbus_channel_unmap_relid(channel);  in hv_process_channel_removal()
464 	if (channel->primary_channel == NULL)  in hv_process_channel_removal()
465 		list_del(&channel->listentry);  in hv_process_channel_removal()
467 		list_del(&channel->sc_list);  in hv_process_channel_removal()
470 	 * If this is a "perf" channel, updates the hv_numa_map[] masks so that  in hv_process_channel_removal()
473 	if (hv_is_perf_channel(channel))  in hv_process_channel_removal()
474 		hv_clear_allocated_cpu(channel->target_cpu);  in hv_process_channel_removal()
477 	 * Upon suspend, an in-use hv_sock channel is marked as "rescinded" and  in hv_process_channel_removal()
479 	 * destroys the channel, the relid is INVALID_RELID, and in this case  in hv_process_channel_removal()
481 	 * relid can refer to a completely different channel now.  in hv_process_channel_removal()
483 	if (channel->offermsg.child_relid != INVALID_RELID)  in hv_process_channel_removal()
484 		vmbus_release_relid(channel->offermsg.child_relid);  in hv_process_channel_removal()
486 	free_channel(channel);  in hv_process_channel_removal()
491 	struct vmbus_channel *channel, *tmp;  in vmbus_free_channels()  local
493 	list_for_each_entry_safe(channel, tmp, &vmbus_connection.chn_list,  in vmbus_free_channels()
496 		channel->rescind = true;  in vmbus_free_channels()
498 		vmbus_device_unregister(channel->device_obj);  in vmbus_free_channels()
512 	 * so that when we do close the channel normally, we  in vmbus_add_channel_work()
518 		/* newchannel is a sub-channel. */  in vmbus_add_channel_work()
532 	 * Start the process of binding the primary channel to the driver  in vmbus_add_channel_work()
577 	/* vmbus_process_offer() has mapped the channel. */  in vmbus_add_channel_work()
588  * vmbus_process_offer - Process the offer by creating a channel/device
593 	struct vmbus_channel *channel;  in vmbus_process_offer()  local
624 	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {  in vmbus_process_offer()
625 		if (guid_equal(&channel->offermsg.offer.if_type,  in vmbus_process_offer()
627 		    guid_equal(&channel->offermsg.offer.if_instance,  in vmbus_process_offer()
630 			newchannel->primary_channel = channel;  in vmbus_process_offer()
652 		 * Check to see if this is a valid sub-channel.  in vmbus_process_offer()
666 		 * Process the sub-channel.  in vmbus_process_offer()
668 		list_add_tail(&newchannel->sc_list, &channel->sc_list);  in vmbus_process_offer()
677 	 * vmbus_process_offer() mustn't call channel->sc_creation_callback()  in vmbus_process_offer()
680 	 * OPEN_CHANNEL message (the host may rescind a channel at any time,  in vmbus_process_offer()
728  * We use this state to statically distribute the channel interrupt load.
733  * We can statically distribute the incoming channel interrupt load
734  * by binding a channel to VCPU.
741 static void init_vp_index(struct vmbus_channel *channel)  in init_vp_index()  argument
743 	bool perf_chn = hv_is_perf_channel(channel);  in init_vp_index()
755 		 * If the channel is not a performance critical  in init_vp_index()
756 		 * channel, bind it to VMBUS_CONNECT_CPU.  in init_vp_index()
762 		channel->target_cpu = VMBUS_CONNECT_CPU;  in init_vp_index()
797 		if (channel->offermsg.offer.sub_channel_index >= ncpu ||  in init_vp_index()
798 		    i > ncpu || !hv_cpuself_used(target_cpu, channel))  in init_vp_index()
802 	channel->target_cpu = target_cpu;  in init_vp_index()
948 static void vmbus_setup_channel_state(struct vmbus_channel *channel,  in vmbus_setup_channel_state()  argument
954 	channel->sig_event = VMBUS_EVENT_CONNECTION_ID;  in vmbus_setup_channel_state()
956 	channel->is_dedicated_interrupt =  in vmbus_setup_channel_state()
958 	channel->sig_event = offer->connection_id;  in vmbus_setup_channel_state()
960 	memcpy(&channel->offermsg, offer,  in vmbus_setup_channel_state()
962 	channel->monitor_grp = (u8)offer->monitorid / 32;  in vmbus_setup_channel_state()
963 	channel->monitor_bit = (u8)offer->monitorid % 32;  in vmbus_setup_channel_state()
964 	channel->device_id = hv_get_dev_type(channel);  in vmbus_setup_channel_state()
968  * find_primary_channel_by_offer - Get the channel object given the new offer.
974 	struct vmbus_channel *channel = NULL, *iter;  in find_primary_channel_by_offer()  local
977 	/* Ignore sub-channel offers. */  in find_primary_channel_by_offer()
988 			channel = iter;  in find_primary_channel_by_offer()
995 	return channel;  in find_primary_channel_by_offer()
1017  * vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
1041 		 * We're resuming from hibernation: all the sub-channel and  in vmbus_onoffer()
1044 		 * primary channel that we had before the hibernation.  in vmbus_onoffer()
1048 		 * { Initially: channel relid = INVALID_RELID,  in vmbus_onoffer()
1056 		 * STORE channel relid = valid_relid	LOAD r1 = channel relid  in vmbus_onoffer()
1057 		 * MAP_RELID channel			if (r1 != INVALID_RELID)  in vmbus_onoffer()
1058 		 * UNLOCK channel_mutex			  UNMAP_RELID channel  in vmbus_onoffer()
1062 		 *              channels[valid_relid] == channel  in vmbus_onoffer()
1064 		 * Note.  r1 can be INVALID_RELID only for an hv_sock channel.  in vmbus_onoffer()
1097 			/* Fix up the old channel. */  in vmbus_onoffer()
1101 		/* Add the channel back to the array of channels. */  in vmbus_onoffer()
1107 	/* Allocate the channel object and save this offer. */  in vmbus_onoffer()
1112 		pr_err("Unable to allocate channel object\n");  in vmbus_onoffer()
1139 	struct vmbus_channel *channel;  in vmbus_onoffer_rescind()  local
1173 		 * We wait here until any channel offer is currently  in vmbus_onoffer_rescind()
1180 	channel = relid2channel(rescind->child_relid);  in vmbus_onoffer_rescind()
1181 	if (channel != NULL) {  in vmbus_onoffer_rescind()
1184 		 * has got a reference to the channel object.  Synchronize on  in vmbus_onoffer_rescind()
1187 		if (channel->rescind_ref) {  in vmbus_onoffer_rescind()
1191 		channel->rescind_ref = true;  in vmbus_onoffer_rescind()
1195 	if (channel == NULL) {  in vmbus_onoffer_rescind()
1204 	clean_up_chan_for_suspend = is_hvsock_channel(channel) ||  in vmbus_onoffer_rescind()
1205 				    is_sub_channel(channel);  in vmbus_onoffer_rescind()
1207 	 * Before setting channel->rescind in vmbus_rescind_cleanup(), we  in vmbus_onoffer_rescind()
1208 	 * should make sure the channel callback is not running any more.  in vmbus_onoffer_rescind()
1210 	vmbus_reset_channel_cb(channel);  in vmbus_onoffer_rescind()
1215 	vmbus_rescind_cleanup(channel);  in vmbus_onoffer_rescind()
1216 	while (READ_ONCE(channel->probe_done) == false) {  in vmbus_onoffer_rescind()
1218 		 * We wait here until any channel offer is currently  in vmbus_onoffer_rescind()
1228 	if (channel->device_obj) {  in vmbus_onoffer_rescind()
1229 		if (channel->chn_rescind_callback) {  in vmbus_onoffer_rescind()
1230 			channel->chn_rescind_callback(channel);  in vmbus_onoffer_rescind()
1241 		dev = get_device(&channel->device_obj->device);  in vmbus_onoffer_rescind()
1243 			vmbus_device_unregister(channel->device_obj);  in vmbus_onoffer_rescind()
1246 	} else if (channel->primary_channel != NULL) {  in vmbus_onoffer_rescind()
1248 		 * Sub-channel is being rescinded. Following is the channel  in vmbus_onoffer_rescind()
1252 		 * 2. Then close the primary channel.  in vmbus_onoffer_rescind()
1255 		if (channel->state == CHANNEL_OPEN_STATE) {  in vmbus_onoffer_rescind()
1257 			 * The channel is currently not open;  in vmbus_onoffer_rescind()
1258 			 * it is safe for us to cleanup the channel.  in vmbus_onoffer_rescind()
1260 			hv_process_channel_removal(channel);  in vmbus_onoffer_rescind()
1262 			complete(&channel->rescind_event);  in vmbus_onoffer_rescind()
1267 	/* The "channel" may have been freed. Do not access it any longer. */  in vmbus_onoffer_rescind()
1273 void vmbus_hvsock_device_unregister(struct vmbus_channel *channel)  in vmbus_hvsock_device_unregister()  argument
1275 	BUG_ON(!is_hvsock_channel(channel));  in vmbus_hvsock_device_unregister()
1278 	while (!READ_ONCE(channel->probe_done) || !READ_ONCE(channel->rescind))  in vmbus_hvsock_device_unregister()
1281 	vmbus_device_unregister(channel->device_obj);  in vmbus_hvsock_device_unregister()
1290  * channel for any virtual hardware configured in the VM at the time it boots.
1295  * devices can be hot-added to the VM after it is booted, additional channel
1303  * NIC channel is opened (once it knows the guest can support it, via the
1315  * This is invoked when we received a response to our channel open request.
1408  * vmbus_onmodifychannel_response - Modify Channel response handler.
1410  * This is invoked when we received a response to our channel modify request.
1531 /* Channel message dispatch table */
1569  * vmbus_onmessage - Handler for channel protocol messages.
1655 void vmbus_set_chn_rescind_callback(struct vmbus_channel *channel,  in vmbus_set_chn_rescind_callback()  argument
1658 	channel->chn_rescind_callback = chn_rescind_cb;  in vmbus_set_chn_rescind_callback()