1 files changed, 32 insertions, 126 deletions

diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index 6ce8b874e833..a8366fec1458 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -93,12 +93,10 @@ static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo,
 	 * all the CPUs. This is needed for kexec to work correctly where
 	 * the CPU attempting to connect may not be CPU 0.
 	 */
-	if (version >= VERSION_WIN8_1) {
-		msg->target_vcpu = hv_context.vp_index[get_cpu()];
-		put_cpu();
-	} else {
+	if (version >= VERSION_WIN8_1)
+		msg->target_vcpu = hv_context.vp_index[smp_processor_id()];
+	else
 		msg->target_vcpu = 0;
-	}
 
 	/*
 	 * Add to list before we send the request since we may
@@ -111,7 +109,8 @@ static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo,
 	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 
 	ret = vmbus_post_msg(msg,
-			       sizeof(struct vmbus_channel_initiate_contact));
+			     sizeof(struct vmbus_channel_initiate_contact),
+			     true);
 	if (ret != 0) {
 		spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 		list_del(&msginfo->msglistentry);
@@ -220,11 +219,8 @@ int vmbus_connect(void)
 		goto cleanup;
 
 	vmbus_proto_version = version;
-	pr_info("Hyper-V Host Build:%d-%d.%d-%d-%d.%d; Vmbus version:%d.%d\n",
-		    host_info_eax, host_info_ebx >> 16,
-		    host_info_ebx & 0xFFFF, host_info_ecx,
-		    host_info_edx >> 24, host_info_edx & 0xFFFFFF,
-		    version >> 16, version & 0xFFFF);
+	pr_info("Vmbus version:%d.%d\n",
+		version >> 16, version & 0xFFFF);
 
 	kfree(msginfo);
 	return 0;
@@ -264,29 +260,6 @@ void vmbus_disconnect(void)
 }
 
 /*
- * Map the given relid to the corresponding channel based on the
- * per-cpu list of channels that have been affinitized to this CPU.
- * This will be used in the channel callback path as we can do this
- * mapping in a lock-free fashion.
- */
-static struct vmbus_channel *pcpu_relid2channel(u32 relid)
-{
-	struct vmbus_channel *channel;
-	struct vmbus_channel *found_channel  = NULL;
-	int cpu = smp_processor_id();
-	struct list_head *pcpu_head = &hv_context.percpu_list[cpu];
-
-	list_for_each_entry(channel, pcpu_head, percpu_list) {
-		if (channel->offermsg.child_relid == relid) {
-			found_channel = channel;
-			break;
-		}
-	}
-
-	return found_channel;
-}
-
-/*
  * relid2channel - Get the channel object given its
  * child relative id (ie channel id)
  */
@@ -322,23 +295,12 @@ struct vmbus_channel *relid2channel(u32 relid)
 }
 
 /*
- * process_chn_event - Process a channel event notification
+ * vmbus_on_event - Process a channel event notification
  */
-static void process_chn_event(u32 relid)
+void vmbus_on_event(unsigned long data)
 {
-	struct vmbus_channel *channel;
-	void *arg;
-	bool read_state;
-	u32 bytes_to_read;
-
-	/*
-	 * Find the channel based on this relid and invokes the
-	 * channel callback to process the event
-	 */
-	channel = pcpu_relid2channel(relid);
-
-	if (!channel)
-		return;
+	struct vmbus_channel *channel = (void *) data;
+	void (*callback_fn)(void *);
 
 	/*
 	 * A channel once created is persistent even when there
@@ -348,10 +310,13 @@ static void process_chn_event(u32 relid)
 	 * Thus, checking and invoking the driver specific callback takes
 	 * care of orderly unloading of the driver.
 	 */
+	callback_fn = READ_ONCE(channel->onchannel_callback);
+	if (unlikely(callback_fn == NULL))
+		return;
 
-	if (channel->onchannel_callback != NULL) {
-		arg = channel->channel_callback_context;
-		read_state = channel->batched_reading;
+	(*callback_fn)(channel->channel_callback_context);
+
+	if (channel->callback_mode == HV_CALL_BATCHED) {
 		/*
 		 * This callback reads the messages sent by the host.
 		 * We can optimize host to guest signaling by ensuring:
@@ -363,71 +328,10 @@ static void process_chn_event(u32 relid)
 		 *    state is set we check to see if additional packets are
 		 *    available to read. In this case we repeat the process.
 		 */
+		if (hv_end_read(&channel->inbound) != 0) {
+			hv_begin_read(&channel->inbound);
 
-		do {
-			if (read_state)
-				hv_begin_read(&channel->inbound);
-			channel->onchannel_callback(arg);
-			if (read_state)
-				bytes_to_read = hv_end_read(&channel->inbound);
-			else
-				bytes_to_read = 0;
-		} while (read_state && (bytes_to_read != 0));
-	}
-}
-
-/*
- * vmbus_on_event - Handler for events
- */
-void vmbus_on_event(unsigned long data)
-{
-	u32 dword;
-	u32 maxdword;
-	int bit;
-	u32 relid;
-	u32 *recv_int_page = NULL;
-	void *page_addr;
-	int cpu = smp_processor_id();
-	union hv_synic_event_flags *event;
-
-	if (vmbus_proto_version < VERSION_WIN8) {
-		maxdword = MAX_NUM_CHANNELS_SUPPORTED >> 5;
-		recv_int_page = vmbus_connection.recv_int_page;
-	} else {
-		/*
-		 * When the host is win8 and beyond, the event page
-		 * can be directly checked to get the id of the channel
-		 * that has the interrupt pending.
-		 */
-		maxdword = HV_EVENT_FLAGS_DWORD_COUNT;
-		page_addr = hv_context.synic_event_page[cpu];
-		event = (union hv_synic_event_flags *)page_addr +
-						 VMBUS_MESSAGE_SINT;
-		recv_int_page = event->flags32;
-	}
-
-
-
-	/* Check events */
-	if (!recv_int_page)
-		return;
-	for (dword = 0; dword < maxdword; dword++) {
-		if (!recv_int_page[dword])
-			continue;
-		for (bit = 0; bit < 32; bit++) {
-			if (sync_test_and_clear_bit(bit,
-				(unsigned long *)&recv_int_page[dword])) {
-				relid = (dword << 5) + bit;
-
-				if (relid == 0)
-					/*
-					 * Special case - vmbus
-					 * channel protocol msg
-					 */
-					continue;
-
-				process_chn_event(relid);
-			}
+			tasklet_schedule(&channel->callback_event);
 		}
 	}
 }
@@ -435,7 +339,7 @@ void vmbus_on_event(unsigned long data)
 /*
  * vmbus_post_msg - Send a msg on the vmbus's message connection
  */
-int vmbus_post_msg(void *buffer, size_t buflen)
+int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep)
 {
 	union hv_connection_id conn_id;
 	int ret = 0;
@@ -450,7 +354,7 @@ int vmbus_post_msg(void *buffer, size_t buflen)
 	 * insufficient resources. Retry the operation a couple of
 	 * times before giving up.
 	 */
-	while (retries < 20) {
+	while (retries < 100) {
 		ret = hv_post_message(conn_id, 1, buffer, buflen);
 
 		switch (ret) {
@@ -473,8 +377,14 @@ int vmbus_post_msg(void *buffer, size_t buflen)
 		}
 
 		retries++;
-		udelay(usec);
-		if (usec < 2048)
+		if (can_sleep && usec > 1000)
+			msleep(usec / 1000);
+		else if (usec < MAX_UDELAY_MS * 1000)
+			udelay(usec);
+		else
+			mdelay(usec / 1000);
+
+		if (usec < 256000)
 			usec *= 2;
 	}
 	return ret;
@@ -487,12 +397,8 @@ void vmbus_set_event(struct vmbus_channel *channel)
 {
 	u32 child_relid = channel->offermsg.child_relid;
 
-	if (!channel->is_dedicated_interrupt) {
-		/* Each u32 represents 32 channels */
-		sync_set_bit(child_relid & 31,
-			(unsigned long *)vmbus_connection.send_int_page +
-			(child_relid >> 5));
-	}
+	if (!channel->is_dedicated_interrupt)
+		vmbus_send_interrupt(child_relid);
 
 	hv_do_hypercall(HVCALL_SIGNAL_EVENT, channel->sig_event, NULL);
 }