7 files changed, 303 insertions, 97 deletions

diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 1161d68a1863..56dd261f7142 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -219,6 +219,21 @@ error0:
 }
 EXPORT_SYMBOL_GPL(vmbus_open);
 
+/* Used for Hyper-V Socket: a guest client's connect() to the host */
+int vmbus_send_tl_connect_request(const uuid_le *shv_guest_servie_id,
+				  const uuid_le *shv_host_servie_id)
+{
+	struct vmbus_channel_tl_connect_request conn_msg;
+
+	memset(&conn_msg, 0, sizeof(conn_msg));
+	conn_msg.header.msgtype = CHANNELMSG_TL_CONNECT_REQUEST;
+	conn_msg.guest_endpoint_id = *shv_guest_servie_id;
+	conn_msg.host_service_id = *shv_host_servie_id;
+
+	return vmbus_post_msg(&conn_msg, sizeof(conn_msg));
+}
+EXPORT_SYMBOL_GPL(vmbus_send_tl_connect_request);
+
 /*
  * create_gpadl_header - Creates a gpadl for the specified buffer
  */
@@ -624,6 +639,7 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer,
 	u64 aligned_data = 0;
 	int ret;
 	bool signal = false;
+	bool lock = channel->acquire_ring_lock;
 	int num_vecs = ((bufferlen != 0) ? 3 : 1);
 
 
@@ -643,7 +659,7 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer,
 	bufferlist[2].iov_len = (packetlen_aligned - packetlen);
 
 	ret = hv_ringbuffer_write(&channel->outbound, bufferlist, num_vecs,
-				  &signal);
+				  &signal, lock);
 
 	/*
 	 * Signalling the host is conditional on many factors:
@@ -659,6 +675,9 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer,
 	 * If we cannot write to the ring-buffer; signal the host
 	 * even if we may not have written anything. This is a rare
 	 * enough condition that it should not matter.
+	 * NOTE: in this case, the hvsock channel is an exception, because
+	 * it looks the host side's hvsock implementation has a throttling
+	 * mechanism which can hurt the performance otherwise.
 	 */
 
 	if (channel->signal_policy)
@@ -666,7 +685,8 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer,
 	else
 		kick_q = true;
 
-	if (((ret == 0) && kick_q && signal) || (ret))
+	if (((ret == 0) && kick_q && signal) ||
+	    (ret && !is_hvsock_channel(channel)))
 		vmbus_setevent(channel);
 
 	return ret;
@@ -719,6 +739,7 @@ int vmbus_sendpacket_pagebuffer_ctl(struct vmbus_channel *channel,
 	struct kvec bufferlist[3];
 	u64 aligned_data = 0;
 	bool signal = false;
+	bool lock = channel->acquire_ring_lock;
 
 	if (pagecount > MAX_PAGE_BUFFER_COUNT)
 		return -EINVAL;
@@ -755,7 +776,8 @@ int vmbus_sendpacket_pagebuffer_ctl(struct vmbus_channel *channel,
 	bufferlist[2].iov_base = &aligned_data;
 	bufferlist[2].iov_len = (packetlen_aligned - packetlen);
 
-	ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
+	ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3,
+				  &signal, lock);
 
 	/*
 	 * Signalling the host is conditional on many factors:
@@ -818,6 +840,7 @@ int vmbus_sendpacket_mpb_desc(struct vmbus_channel *channel,
 	struct kvec bufferlist[3];
 	u64 aligned_data = 0;
 	bool signal = false;
+	bool lock = channel->acquire_ring_lock;
 
 	packetlen = desc_size + bufferlen;
 	packetlen_aligned = ALIGN(packetlen, sizeof(u64));
@@ -837,7 +860,8 @@ int vmbus_sendpacket_mpb_desc(struct vmbus_channel *channel,
 	bufferlist[2].iov_base = &aligned_data;
 	bufferlist[2].iov_len = (packetlen_aligned - packetlen);
 
-	ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
+	ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3,
+				  &signal, lock);
 
 	if (ret == 0 && signal)
 		vmbus_setevent(channel);
@@ -862,6 +886,7 @@ int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
 	struct kvec bufferlist[3];
 	u64 aligned_data = 0;
 	bool signal = false;
+	bool lock = channel->acquire_ring_lock;
 	u32 pfncount = NUM_PAGES_SPANNED(multi_pagebuffer->offset,
 					 multi_pagebuffer->len);
 
@@ -900,7 +925,8 @@ int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
 	bufferlist[2].iov_base = &aligned_data;
 	bufferlist[2].iov_len = (packetlen_aligned - packetlen);
 
-	ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
+	ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3,
+				  &signal, lock);
 
 	if (ret == 0 && signal)
 		vmbus_setevent(channel);
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 1c1ad47042c5..b40f429aaa13 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -28,12 +28,127 @@
 #include <linux/list.h>
 #include <linux/module.h>
 #include <linux/completion.h>
+#include <linux/delay.h>
 #include <linux/hyperv.h>
 
 #include "hyperv_vmbus.h"
 
-static void init_vp_index(struct vmbus_channel *channel,
-			  const uuid_le *type_guid);
+static void init_vp_index(struct vmbus_channel *channel, u16 dev_type);
+
+static const struct vmbus_device vmbus_devs[] = {
+	/* IDE */
+	{ .dev_type = HV_IDE,
+	  HV_IDE_GUID,
+	  .perf_device = true,
+	},
+
+	/* SCSI */
+	{ .dev_type = HV_SCSI,
+	  HV_SCSI_GUID,
+	  .perf_device = true,
+	},
+
+	/* Fibre Channel */
+	{ .dev_type = HV_FC,
+	  HV_SYNTHFC_GUID,
+	  .perf_device = true,
+	},
+
+	/* Synthetic NIC */
+	{ .dev_type = HV_NIC,
+	  HV_NIC_GUID,
+	  .perf_device = true,
+	},
+
+	/* Network Direct */
+	{ .dev_type = HV_ND,
+	  HV_ND_GUID,
+	  .perf_device = true,
+	},
+
+	/* PCIE */
+	{ .dev_type = HV_PCIE,
+	  HV_PCIE_GUID,
+	  .perf_device = true,
+	},
+
+	/* Synthetic Frame Buffer */
+	{ .dev_type = HV_FB,
+	  HV_SYNTHVID_GUID,
+	  .perf_device = false,
+	},
+
+	/* Synthetic Keyboard */
+	{ .dev_type = HV_KBD,
+	  HV_KBD_GUID,
+	  .perf_device = false,
+	},
+
+	/* Synthetic MOUSE */
+	{ .dev_type = HV_MOUSE,
+	  HV_MOUSE_GUID,
+	  .perf_device = false,
+	},
+
+	/* KVP */
+	{ .dev_type = HV_KVP,
+	  HV_KVP_GUID,
+	  .perf_device = false,
+	},
+
+	/* Time Synch */
+	{ .dev_type = HV_TS,
+	  HV_TS_GUID,
+	  .perf_device = false,
+	},
+
+	/* Heartbeat */
+	{ .dev_type = HV_HB,
+	  HV_HEART_BEAT_GUID,
+	  .perf_device = false,
+	},
+
+	/* Shutdown */
+	{ .dev_type = HV_SHUTDOWN,
+	  HV_SHUTDOWN_GUID,
+	  .perf_device = false,
+	},
+
+	/* File copy */
+	{ .dev_type = HV_FCOPY,
+	  HV_FCOPY_GUID,
+	  .perf_device = false,
+	},
+
+	/* Backup */
+	{ .dev_type = HV_BACKUP,
+	  HV_VSS_GUID,
+	  .perf_device = false,
+	},
+
+	/* Dynamic Memory */
+	{ .dev_type = HV_DM,
+	  HV_DM_GUID,
+	  .perf_device = false,
+	},
+
+	/* Unknown GUID */
+	{ .dev_type = HV_UNKOWN,
+	  .perf_device = false,
+	},
+};
+
+static u16 hv_get_dev_type(const uuid_le *guid)
+{
+	u16 i;
+
+	for (i = HV_IDE; i < HV_UNKOWN; i++) {
+		if (!uuid_le_cmp(*guid, vmbus_devs[i].guid))
+			return i;
+	}
+	pr_info("Unknown GUID: %pUl\n", guid);
+	return i;
+}
 
 /**
  * vmbus_prep_negotiate_resp() - Create default response for Hyper-V Negotiate message
@@ -144,6 +259,7 @@ static struct vmbus_channel *alloc_channel(void)
 		return NULL;
 
 	channel->id = atomic_inc_return(&chan_num);
+	channel->acquire_ring_lock = true;
 	spin_lock_init(&channel->inbound_lock);
 	spin_lock_init(&channel->lock);
 
@@ -195,6 +311,7 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
 	vmbus_release_relid(relid);
 
 	BUG_ON(!channel->rescind);
+	BUG_ON(!mutex_is_locked(&vmbus_connection.channel_mutex));
 
 	if (channel->target_cpu != get_cpu()) {
 		put_cpu();
@@ -206,9 +323,7 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
 	}
 
 	if (channel->primary_channel == NULL) {
-		mutex_lock(&vmbus_connection.channel_mutex);
 		list_del(&channel->listentry);
-		mutex_unlock(&vmbus_connection.channel_mutex);
 
 		primary_channel = channel;
 	} else {
@@ -251,6 +366,8 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
 	struct vmbus_channel *channel;
 	bool fnew = true;
 	unsigned long flags;
+	u16 dev_type;
+	int ret;
 
 	/* Make sure this is a new offer */
 	mutex_lock(&vmbus_connection.channel_mutex);
@@ -288,7 +405,9 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
 			goto err_free_chan;
 	}
 
-	init_vp_index(newchannel, &newchannel->offermsg.offer.if_type);
+	dev_type = hv_get_dev_type(&newchannel->offermsg.offer.if_type);
+
+	init_vp_index(newchannel, dev_type);
 
 	if (newchannel->target_cpu != get_cpu()) {
 		put_cpu();
@@ -325,12 +444,17 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
 	if (!newchannel->device_obj)
 		goto err_deq_chan;
 
+	newchannel->device_obj->device_id = dev_type;
 	/*
 	 * Add the new device to the bus. This will kick off device-driver
 	 * binding which eventually invokes the device driver's AddDevice()
 	 * method.
 	 */
-	if (vmbus_device_register(newchannel->device_obj) != 0) {
+	mutex_lock(&vmbus_connection.channel_mutex);
+	ret = vmbus_device_register(newchannel->device_obj);
+	mutex_unlock(&vmbus_connection.channel_mutex);
+
+	if (ret != 0) {
 		pr_err("unable to add child device object (relid %d)\n",
 			newchannel->offermsg.child_relid);
 		kfree(newchannel->device_obj);
@@ -358,37 +482,6 @@ err_free_chan:
 	free_channel(newchannel);
 }
 
-enum {
-	IDE = 0,
-	SCSI,
-	FC,
-	NIC,
-	ND_NIC,
-	PCIE,
-	MAX_PERF_CHN,
-};
-
-/*
- * This is an array of device_ids (device types) that are performance critical.
- * We attempt to distribute the interrupt load for these devices across
- * all available CPUs.
- */
-static const struct hv_vmbus_device_id hp_devs[] = {
-	/* IDE */
-	{ HV_IDE_GUID, },
-	/* Storage - SCSI */
-	{ HV_SCSI_GUID, },
-	/* Storage - FC */
-	{ HV_SYNTHFC_GUID, },
-	/* Network */
-	{ HV_NIC_GUID, },
-	/* NetworkDirect Guest RDMA */
-	{ HV_ND_GUID, },
-	/* PCI Express Pass Through */
-	{ HV_PCIE_GUID, },
-};
-
-
 /*
  * We use this state to statically distribute the channel interrupt load.
  */
@@ -405,22 +498,15 @@ static int next_numa_node_id;
  * For pre-win8 hosts or non-performance critical channels we assign the
  * first CPU in the first NUMA node.
  */
-static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_guid)
+static void init_vp_index(struct vmbus_channel *channel, u16 dev_type)
 {
 	u32 cur_cpu;
-	int i;
-	bool perf_chn = false;
+	bool perf_chn = vmbus_devs[dev_type].perf_device;
 	struct vmbus_channel *primary = channel->primary_channel;
 	int next_node;
 	struct cpumask available_mask;
 	struct cpumask *alloced_mask;
 
-	for (i = IDE; i < MAX_PERF_CHN; i++) {
-		if (!uuid_le_cmp(*type_guid, hp_devs[i].guid)) {
-			perf_chn = true;
-			break;
-		}
-	}
 	if ((vmbus_proto_version == VERSION_WS2008) ||
 	    (vmbus_proto_version == VERSION_WIN7) || (!perf_chn)) {
 		/*
@@ -469,6 +555,17 @@ static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_gui
 		    cpumask_of_node(primary->numa_node));
 
 	cur_cpu = -1;
+
+	/*
+	 * Normally Hyper-V host doesn't create more subchannels than there
+	 * are VCPUs on the node but it is possible when not all present VCPUs
+	 * on the node are initialized by guest. Clear the alloced_cpus_in_node
+	 * to start over.
+	 */
+	if (cpumask_equal(&primary->alloced_cpus_in_node,
+			  cpumask_of_node(primary->numa_node)))
+		cpumask_clear(&primary->alloced_cpus_in_node);
+
 	while (true) {
 		cur_cpu = cpumask_next(cur_cpu, &available_mask);
 		if (cur_cpu >= nr_cpu_ids) {
@@ -498,6 +595,40 @@ static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_gui
 	channel->target_vp = hv_context.vp_index[cur_cpu];
 }
 
+static void vmbus_wait_for_unload(void)
+{
+	int cpu = smp_processor_id();
+	void *page_addr = hv_context.synic_message_page[cpu];
+	struct hv_message *msg = (struct hv_message *)page_addr +
+				  VMBUS_MESSAGE_SINT;
+	struct vmbus_channel_message_header *hdr;
+	bool unloaded = false;
+
+	while (1) {
+		if (msg->header.message_type == HVMSG_NONE) {
+			mdelay(10);
+			continue;
+		}
+
+		hdr = (struct vmbus_channel_message_header *)msg->u.payload;
+		if (hdr->msgtype == CHANNELMSG_UNLOAD_RESPONSE)
+			unloaded = true;
+
+		msg->header.message_type = HVMSG_NONE;
+		/*
+		 * header.message_type needs to be written before we do
+		 * wrmsrl() below.
+		 */
+		mb();
+
+		if (msg->header.message_flags.msg_pending)
+			wrmsrl(HV_X64_MSR_EOM, 0);
+
+		if (unloaded)
+			break;
+	}
+}
+
 /*
  * vmbus_unload_response - Handler for the unload response.
  */
@@ -523,7 +654,14 @@ void vmbus_initiate_unload(void)
 	hdr.msgtype = CHANNELMSG_UNLOAD;
 	vmbus_post_msg(&hdr, sizeof(struct vmbus_channel_message_header));
 
-	wait_for_completion(&vmbus_connection.unload_event);
+	/*
+	 * vmbus_initiate_unload() is also called on crash and the crash can be
+	 * happening in an interrupt context, where scheduling is impossible.
+	 */
+	if (!in_interrupt())
+		wait_for_completion(&vmbus_connection.unload_event);
+	else
+		vmbus_wait_for_unload();
 }
 
 /*
@@ -592,6 +730,8 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
 	struct device *dev;
 
 	rescind = (struct vmbus_channel_rescind_offer *)hdr;
+
+	mutex_lock(&vmbus_connection.channel_mutex);
 	channel = relid2channel(rescind->child_relid);
 
 	if (channel == NULL) {
@@ -600,7 +740,7 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
 		 * vmbus_process_offer(), we have already invoked
 		 * vmbus_release_relid() on error.
 		 */
-		return;
+		goto out;
 	}
 
 	spin_lock_irqsave(&channel->lock, flags);
@@ -608,6 +748,10 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
 	spin_unlock_irqrestore(&channel->lock, flags);
 
 	if (channel->device_obj) {
+		if (channel->chn_rescind_callback) {
+			channel->chn_rescind_callback(channel);
+			goto out;
+		}
 		/*
 		 * We will have to unregister this device from the
 		 * driver core.
@@ -621,8 +765,25 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
 		hv_process_channel_removal(channel,
 			channel->offermsg.child_relid);
 	}
+
+out:
+	mutex_unlock(&vmbus_connection.channel_mutex);
 }
 
+void vmbus_hvsock_device_unregister(struct vmbus_channel *channel)
+{
+	mutex_lock(&vmbus_connection.channel_mutex);
+
+	BUG_ON(!is_hvsock_channel(channel));
+
+	channel->rescind = true;
+	vmbus_device_unregister(channel->device_obj);
+
+	mutex_unlock(&vmbus_connection.channel_mutex);
+}
+EXPORT_SYMBOL_GPL(vmbus_hvsock_device_unregister);
+
+
 /*
  * vmbus_onoffers_delivered -
  * This is invoked when all offers have been delivered.
@@ -825,6 +986,10 @@ struct vmbus_channel_message_table_entry
 	{CHANNELMSG_VERSION_RESPONSE,		1, vmbus_onversion_response},
 	{CHANNELMSG_UNLOAD,			0, NULL},
 	{CHANNELMSG_UNLOAD_RESPONSE,		1, vmbus_unload_response},
+	{CHANNELMSG_18,				0, NULL},
+	{CHANNELMSG_19,				0, NULL},
+	{CHANNELMSG_20,				0, NULL},
+	{CHANNELMSG_TL_CONNECT_REQUEST,		0, NULL},
 };
 
 /*
@@ -973,3 +1138,10 @@ bool vmbus_are_subchannels_present(struct vmbus_channel *primary)
 	return ret;
 }
 EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present);
+
+void vmbus_set_chn_rescind_callback(struct vmbus_channel *channel,
+		void (*chn_rescind_cb)(struct vmbus_channel *))
+{
+	channel->chn_rescind_callback = chn_rescind_cb;
+}
+EXPORT_SYMBOL_GPL(vmbus_set_chn_rescind_callback);
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index 3dc5a9c7fad6..fa86b2cb28b8 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -288,7 +288,8 @@ struct vmbus_channel *relid2channel(u32 relid)
 	struct list_head *cur, *tmp;
 	struct vmbus_channel *cur_sc;
 
-	mutex_lock(&vmbus_connection.channel_mutex);
+	BUG_ON(!mutex_is_locked(&vmbus_connection.channel_mutex));
+
 	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
 		if (channel->offermsg.child_relid == relid) {
 			found_channel = channel;
@@ -307,7 +308,6 @@ struct vmbus_channel *relid2channel(u32 relid)
 			}
 		}
 	}
-	mutex_unlock(&vmbus_connection.channel_mutex);
 
 	return found_channel;
 }
@@ -474,7 +474,7 @@ int vmbus_post_msg(void *buffer, size_t buflen)
 /*
  * vmbus_set_event - Send an event notification to the parent
  */
-int vmbus_set_event(struct vmbus_channel *channel)
+void vmbus_set_event(struct vmbus_channel *channel)
 {
 	u32 child_relid = channel->offermsg.child_relid;
 
@@ -485,5 +485,5 @@ int vmbus_set_event(struct vmbus_channel *channel)
 			(child_relid >> 5));
 	}
 
-	return hv_signal_event(channel->sig_event);
+	hv_do_hypercall(HVCALL_SIGNAL_EVENT, channel->sig_event, NULL);
 }
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 11bca51ef5ff..ccb335f57c88 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -295,8 +295,14 @@ void hv_cleanup(void)
 	 * Cleanup the TSC page based CS.
 	 */
 	if (ms_hyperv.features & HV_X64_MSR_REFERENCE_TSC_AVAILABLE) {
-		clocksource_change_rating(&hyperv_cs_tsc, 10);
-		clocksource_unregister(&hyperv_cs_tsc);
+		/*
+		 * Crash can happen in an interrupt context and unregistering
+		 * a clocksource is impossible and redundant in this case.
+		 */
+		if (!oops_in_progress) {
+			clocksource_change_rating(&hyperv_cs_tsc, 10);
+			clocksource_unregister(&hyperv_cs_tsc);
+		}
 
 		hypercall_msr.as_uint64 = 0;
 		wrmsrl(HV_X64_MSR_REFERENCE_TSC, hypercall_msr.as_uint64);
@@ -337,22 +343,6 @@ int hv_post_message(union hv_connection_id connection_id,
 	return status & 0xFFFF;
 }
 
-
-/*
- * hv_signal_event -
- * Signal an event on the specified connection using the hypervisor event IPC.
- *
- * This involves a hypercall.
- */
-int hv_signal_event(void *con_id)
-{
-	u64 status;
-
-	status = hv_do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL);
-
-	return status & 0xFFFF;
-}
-
 static int hv_ce_set_next_event(unsigned long delta,
 				struct clock_event_device *evt)
 {
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 4ebc796b4f33..b9ea7f59036b 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -501,8 +501,6 @@ extern int hv_post_message(union hv_connection_id connection_id,
 			 enum hv_message_type message_type,
 			 void *payload, size_t payload_size);
 
-extern int hv_signal_event(void *con_id);
-
 extern int hv_synic_alloc(void);
 
 extern void hv_synic_free(void);
@@ -531,7 +529,7 @@ void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
 
 int hv_ringbuffer_write(struct hv_ring_buffer_info *ring_info,
 		    struct kvec *kv_list,
-		    u32 kv_count, bool *signal);
+		    u32 kv_count, bool *signal, bool lock);
 
 int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
 		       void *buffer, u32 buflen, u32 *buffer_actual_len,
@@ -650,7 +648,7 @@ void vmbus_disconnect(void);
 
 int vmbus_post_msg(void *buffer, size_t buflen);
 
-int vmbus_set_event(struct vmbus_channel *channel);
+void vmbus_set_event(struct vmbus_channel *channel);
 
 void vmbus_on_event(unsigned long data);
 
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index b53702ce692f..5613e2b5cff7 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -314,7 +314,7 @@ void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info)
 
 /* Write to the ring buffer. */
 int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
-		    struct kvec *kv_list, u32 kv_count, bool *signal)
+		    struct kvec *kv_list, u32 kv_count, bool *signal, bool lock)
 {
 	int i = 0;
 	u32 bytes_avail_towrite;
@@ -324,14 +324,15 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
 	u32 next_write_location;
 	u32 old_write;
 	u64 prev_indices = 0;
-	unsigned long flags;
+	unsigned long flags = 0;
 
 	for (i = 0; i < kv_count; i++)
 		totalbytes_towrite += kv_list[i].iov_len;
 
 	totalbytes_towrite += sizeof(u64);
 
-	spin_lock_irqsave(&outring_info->ring_lock, flags);
+	if (lock)
+		spin_lock_irqsave(&outring_info->ring_lock, flags);
 
 	hv_get_ringbuffer_availbytes(outring_info,
 				&bytes_avail_toread,
@@ -343,7 +344,8 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
 	 * is empty since the read index == write index.
 	 */
 	if (bytes_avail_towrite <= totalbytes_towrite) {
-		spin_unlock_irqrestore(&outring_info->ring_lock, flags);
+		if (lock)
+			spin_unlock_irqrestore(&outring_info->ring_lock, flags);
 		return -EAGAIN;
 	}
 
@@ -374,7 +376,8 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
 	hv_set_next_write_location(outring_info, next_write_location);
 
 
-	spin_unlock_irqrestore(&outring_info->ring_lock, flags);
+	if (lock)
+		spin_unlock_irqrestore(&outring_info->ring_lock, flags);
 
 	*signal = hv_need_to_signal(old_write, outring_info);
 	return 0;
@@ -388,7 +391,6 @@ int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
 	u32 bytes_avail_toread;
 	u32 next_read_location = 0;
 	u64 prev_indices = 0;
-	unsigned long flags;
 	struct vmpacket_descriptor desc;
 	u32 offset;
 	u32 packetlen;
@@ -397,7 +399,6 @@ int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
 	if (buflen <= 0)
 		return -EINVAL;
 
-	spin_lock_irqsave(&inring_info->ring_lock, flags);
 
 	*buffer_actual_len = 0;
 	*requestid = 0;
@@ -412,7 +413,7 @@ int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
 		 * No error is set when there is even no header, drivers are
 		 * supposed to analyze buffer_actual_len.
 		 */
-		goto out_unlock;
+		return ret;
 	}
 
 	next_read_location = hv_get_next_read_location(inring_info);
@@ -425,15 +426,11 @@ int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
 	*buffer_actual_len = packetlen;
 	*requestid = desc.trans_id;
 
-	if (bytes_avail_toread < packetlen + offset) {
-		ret = -EAGAIN;
-		goto out_unlock;
-	}
+	if (bytes_avail_toread < packetlen + offset)
+		return -EAGAIN;
 
-	if (packetlen > buflen) {
-		ret = -ENOBUFS;
-		goto out_unlock;
-	}
+	if (packetlen > buflen)
+		return -ENOBUFS;
 
 	next_read_location =
 		hv_get_next_readlocation_withoffset(inring_info, offset);
@@ -460,7 +457,5 @@ int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
 
 	*signal = hv_need_to_signal_on_read(bytes_avail_towrite, inring_info);
 
-out_unlock:
-	spin_unlock_irqrestore(&inring_info->ring_lock, flags);
 	return ret;
 }
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 328e4c3808e0..063e5f53ca78 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -477,6 +477,24 @@ static ssize_t channel_vp_mapping_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(channel_vp_mapping);
 
+static ssize_t vendor_show(struct device *dev,
+			   struct device_attribute *dev_attr,
+			   char *buf)
+{
+	struct hv_device *hv_dev = device_to_hv_device(dev);
+	return sprintf(buf, "0x%x\n", hv_dev->vendor_id);
+}
+static DEVICE_ATTR_RO(vendor);
+
+static ssize_t device_show(struct device *dev,
+			   struct device_attribute *dev_attr,
+			   char *buf)
+{
+	struct hv_device *hv_dev = device_to_hv_device(dev);
+	return sprintf(buf, "0x%x\n", hv_dev->device_id);
+}
+static DEVICE_ATTR_RO(device);
+
 /* Set up per device attributes in /sys/bus/vmbus/devices/<bus device> */
 static struct attribute *vmbus_attrs[] = {
 	&dev_attr_id.attr,
@@ -502,6 +520,8 @@ static struct attribute *vmbus_attrs[] = {
 	&dev_attr_in_read_bytes_avail.attr,
 	&dev_attr_in_write_bytes_avail.attr,
 	&dev_attr_channel_vp_mapping.attr,
+	&dev_attr_vendor.attr,
+	&dev_attr_device.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(vmbus);
@@ -562,6 +582,10 @@ static int vmbus_match(struct device *device, struct device_driver *driver)
 	struct hv_driver *drv = drv_to_hv_drv(driver);
 	struct hv_device *hv_dev = device_to_hv_device(device);
 
+	/* The hv_sock driver handles all hv_sock offers. */
+	if (is_hvsock_channel(hv_dev->channel))
+		return drv->hvsock;
+
 	if (hv_vmbus_get_id(drv->id_table, &hv_dev->dev_type))
 		return 1;
 
@@ -957,6 +981,7 @@ struct hv_device *vmbus_device_create(const uuid_le *type,
 	memcpy(&child_device_obj->dev_type, type, sizeof(uuid_le));
 	memcpy(&child_device_obj->dev_instance, instance,
 	       sizeof(uuid_le));
+	child_device_obj->vendor_id = 0x1414; /* MSFT vendor ID */
 
 
 	return child_device_obj;