1 files changed, 107 insertions, 69 deletions

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 26b419203f16..fbcb06352308 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -31,6 +31,7 @@
 #include <linux/completion.h>
 #include <linux/delay.h>
 #include <linux/hyperv.h>
+#include <asm/mshyperv.h>
 
 #include "hyperv_vmbus.h"
 
@@ -147,6 +148,29 @@ static const struct {
 	{ HV_RDV_GUID	},
 };
 
+/*
+ * The rescinded channel may be blocked waiting for a response from the host;
+ * take care of that.
+ */
+static void vmbus_rescind_cleanup(struct vmbus_channel *channel)
+{
+	struct vmbus_channel_msginfo *msginfo;
+	unsigned long flags;
+
+
+	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+
+	list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
+				msglistentry) {
+
+		if (msginfo->waiting_channel == channel) {
+			complete(&msginfo->waitevent);
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+}
+
 static bool is_unsupported_vmbus_devs(const uuid_le *guid)
 {
 	int i;
@@ -180,33 +204,34 @@ static u16 hv_get_dev_type(const struct vmbus_channel *channel)
  * @buf: Raw buffer channel data
  *
  * @icmsghdrp is of type &struct icmsg_hdr.
- * @negop is of type &struct icmsg_negotiate.
  * Set up and fill in default negotiate response message.
  *
- * The fw_version specifies the  framework version that
- * we can support and srv_version specifies the service
- * version we can support.
+ * The fw_version and fw_vercnt specifies the framework version that
+ * we can support.
+ *
+ * The srv_version and srv_vercnt specifies the service
+ * versions we can support.
+ *
+ * Versions are given in decreasing order.
+ *
+ * nego_fw_version and nego_srv_version store the selected protocol versions.
  *
  * Mainly used by Hyper-V drivers.
  */
 bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
-				struct icmsg_negotiate *negop, u8 *buf,
-				int fw_version, int srv_version)
+				u8 *buf, const int *fw_version, int fw_vercnt,
+				const int *srv_version, int srv_vercnt,
+				int *nego_fw_version, int *nego_srv_version)
 {
 	int icframe_major, icframe_minor;
 	int icmsg_major, icmsg_minor;
 	int fw_major, fw_minor;
 	int srv_major, srv_minor;
-	int i;
+	int i, j;
 	bool found_match = false;
+	struct icmsg_negotiate *negop;
 
 	icmsghdrp->icmsgsize = 0x10;
-	fw_major = (fw_version >> 16);
-	fw_minor = (fw_version & 0xFFFF);
-
-	srv_major = (srv_version >> 16);
-	srv_minor = (srv_version & 0xFFFF);
-
 	negop = (struct icmsg_negotiate *)&buf[
 		sizeof(struct vmbuspipe_hdr) +
 		sizeof(struct icmsg_hdr)];
@@ -222,13 +247,22 @@ bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
 	 * support.
 	 */
 
-	for (i = 0; i < negop->icframe_vercnt; i++) {
-		if ((negop->icversion_data[i].major == fw_major) &&
-		   (negop->icversion_data[i].minor == fw_minor)) {
-			icframe_major = negop->icversion_data[i].major;
-			icframe_minor = negop->icversion_data[i].minor;
-			found_match = true;
+	for (i = 0; i < fw_vercnt; i++) {
+		fw_major = (fw_version[i] >> 16);
+		fw_minor = (fw_version[i] & 0xFFFF);
+
+		for (j = 0; j < negop->icframe_vercnt; j++) {
+			if ((negop->icversion_data[j].major == fw_major) &&
+			    (negop->icversion_data[j].minor == fw_minor)) {
+				icframe_major = negop->icversion_data[j].major;
+				icframe_minor = negop->icversion_data[j].minor;
+				found_match = true;
+				break;
+			}
 		}
+
+		if (found_match)
+			break;
 	}
 
 	if (!found_match)
@@ -236,14 +270,26 @@ bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
 
 	found_match = false;
 
-	for (i = negop->icframe_vercnt;
-		 (i < negop->icframe_vercnt + negop->icmsg_vercnt); i++) {
-		if ((negop->icversion_data[i].major == srv_major) &&
-		   (negop->icversion_data[i].minor == srv_minor)) {
-			icmsg_major = negop->icversion_data[i].major;
-			icmsg_minor = negop->icversion_data[i].minor;
-			found_match = true;
+	for (i = 0; i < srv_vercnt; i++) {
+		srv_major = (srv_version[i] >> 16);
+		srv_minor = (srv_version[i] & 0xFFFF);
+
+		for (j = negop->icframe_vercnt;
+			(j < negop->icframe_vercnt + negop->icmsg_vercnt);
+			j++) {
+
+			if ((negop->icversion_data[j].major == srv_major) &&
+				(negop->icversion_data[j].minor == srv_minor)) {
+
+				icmsg_major = negop->icversion_data[j].major;
+				icmsg_minor = negop->icversion_data[j].minor;
+				found_match = true;
+				break;
+			}
 		}
+
+		if (found_match)
+			break;
 	}
 
 	/*
@@ -260,6 +306,12 @@ fw_error:
 		negop->icmsg_vercnt = 1;
 	}
 
+	if (nego_fw_version)
+		*nego_fw_version = (icframe_major << 16) | icframe_minor;
+
+	if (nego_srv_version)
+		*nego_srv_version = (icmsg_major << 16) | icmsg_minor;
+
 	negop->icversion_data[0].major = icframe_major;
 	negop->icversion_data[0].minor = icframe_minor;
 	negop->icversion_data[1].major = icmsg_major;
@@ -280,13 +332,15 @@ static struct vmbus_channel *alloc_channel(void)
 	if (!channel)
 		return NULL;
 
-	channel->acquire_ring_lock = true;
 	spin_lock_init(&channel->inbound_lock);
 	spin_lock_init(&channel->lock);
 
 	INIT_LIST_HEAD(&channel->sc_list);
 	INIT_LIST_HEAD(&channel->percpu_list);
 
+	tasklet_init(&channel->callback_event,
+		     vmbus_on_event, (unsigned long)channel);
+
 	return channel;
 }
 
@@ -295,22 +349,25 @@ static struct vmbus_channel *alloc_channel(void)
  */
 static void free_channel(struct vmbus_channel *channel)
 {
-	kfree(channel);
+	tasklet_kill(&channel->callback_event);
+
+	kfree_rcu(channel, rcu);
 }
 
 static void percpu_channel_enq(void *arg)
 {
 	struct vmbus_channel *channel = arg;
-	int cpu = smp_processor_id();
+	struct hv_per_cpu_context *hv_cpu
+		= this_cpu_ptr(hv_context.cpu_context);
 
-	list_add_tail(&channel->percpu_list, &hv_context.percpu_list[cpu]);
+	list_add_tail_rcu(&channel->percpu_list, &hv_cpu->chan_list);
 }
 
 static void percpu_channel_deq(void *arg)
 {
 	struct vmbus_channel *channel = arg;
 
-	list_del(&channel->percpu_list);
+	list_del_rcu(&channel->percpu_list);
 }
 
 
@@ -321,24 +378,8 @@ static void vmbus_release_relid(u32 relid)
 	memset(&msg, 0, sizeof(struct vmbus_channel_relid_released));
 	msg.child_relid = relid;
 	msg.header.msgtype = CHANNELMSG_RELID_RELEASED;
-	vmbus_post_msg(&msg, sizeof(struct vmbus_channel_relid_released));
-}
-
-void hv_event_tasklet_disable(struct vmbus_channel *channel)
-{
-	struct tasklet_struct *tasklet;
-	tasklet = hv_context.event_dpc[channel->target_cpu];
-	tasklet_disable(tasklet);
-}
-
-void hv_event_tasklet_enable(struct vmbus_channel *channel)
-{
-	struct tasklet_struct *tasklet;
-	tasklet = hv_context.event_dpc[channel->target_cpu];
-	tasklet_enable(tasklet);
-
-	/* In case there is any pending event */
-	tasklet_schedule(tasklet);
+	vmbus_post_msg(&msg, sizeof(struct vmbus_channel_relid_released),
+		       true);
 }
 
 void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
@@ -349,7 +390,6 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
 	BUG_ON(!channel->rescind);
 	BUG_ON(!mutex_is_locked(&vmbus_connection.channel_mutex));
 
-	hv_event_tasklet_disable(channel);
 	if (channel->target_cpu != get_cpu()) {
 		put_cpu();
 		smp_call_function_single(channel->target_cpu,
@@ -358,7 +398,6 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
 		percpu_channel_deq(channel);
 		put_cpu();
 	}
-	hv_event_tasklet_enable(channel);
 
 	if (channel->primary_channel == NULL) {
 		list_del(&channel->listentry);
@@ -452,7 +491,6 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
 
 	init_vp_index(newchannel, dev_type);
 
-	hv_event_tasklet_disable(newchannel);
 	if (newchannel->target_cpu != get_cpu()) {
 		put_cpu();
 		smp_call_function_single(newchannel->target_cpu,
@@ -462,7 +500,6 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
 		percpu_channel_enq(newchannel);
 		put_cpu();
 	}
-	hv_event_tasklet_enable(newchannel);
 
 	/*
 	 * This state is used to indicate a successful open
@@ -512,7 +549,6 @@ err_deq_chan:
 	list_del(&newchannel->listentry);
 	mutex_unlock(&vmbus_connection.channel_mutex);
 
-	hv_event_tasklet_disable(newchannel);
 	if (newchannel->target_cpu != get_cpu()) {
 		put_cpu();
 		smp_call_function_single(newchannel->target_cpu,
@@ -521,7 +557,6 @@ err_deq_chan:
 		percpu_channel_deq(newchannel);
 		put_cpu();
 	}
-	hv_event_tasklet_enable(newchannel);
 
 	vmbus_release_relid(newchannel->offermsg.child_relid);
 
@@ -673,9 +708,12 @@ static void vmbus_wait_for_unload(void)
 			break;
 
 		for_each_online_cpu(cpu) {
-			page_addr = hv_context.synic_message_page[cpu];
-			msg = (struct hv_message *)page_addr +
-				VMBUS_MESSAGE_SINT;
+			struct hv_per_cpu_context *hv_cpu
+				= per_cpu_ptr(hv_context.cpu_context, cpu);
+
+			page_addr = hv_cpu->synic_message_page;
+			msg = (struct hv_message *)page_addr
+				+ VMBUS_MESSAGE_SINT;
 
 			message_type = READ_ONCE(msg->header.message_type);
 			if (message_type == HVMSG_NONE)
@@ -699,7 +737,10 @@ static void vmbus_wait_for_unload(void)
 	 * messages after we reconnect.
 	 */
 	for_each_online_cpu(cpu) {
-		page_addr = hv_context.synic_message_page[cpu];
+		struct hv_per_cpu_context *hv_cpu
+			= per_cpu_ptr(hv_context.cpu_context, cpu);
+
+		page_addr = hv_cpu->synic_message_page;
 		msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
 		msg->header.message_type = HVMSG_NONE;
 	}
@@ -728,7 +769,8 @@ void vmbus_initiate_unload(bool crash)
 	init_completion(&vmbus_connection.unload_event);
 	memset(&hdr, 0, sizeof(struct vmbus_channel_message_header));
 	hdr.msgtype = CHANNELMSG_UNLOAD;
-	vmbus_post_msg(&hdr, sizeof(struct vmbus_channel_message_header));
+	vmbus_post_msg(&hdr, sizeof(struct vmbus_channel_message_header),
+		       !crash);
 
 	/*
 	 * vmbus_initiate_unload() is also called on crash and the crash can be
@@ -754,18 +796,12 @@ static void vmbus_onoffer(struct vmbus_channel_message_header *hdr)
 	/* Allocate the channel object and save this offer. */
 	newchannel = alloc_channel();
 	if (!newchannel) {
+		vmbus_release_relid(offer->child_relid);
 		pr_err("Unable to allocate channel object\n");
 		return;
 	}
 
 	/*
-	 * By default we setup state to enable batched
-	 * reading. A specific service can choose to
-	 * disable this prior to opening the channel.
-	 */
-	newchannel->batched_reading = true;
-
-	/*
 	 * Setup state for signalling the host.
 	 */
 	newchannel->sig_event = (struct hv_input_signal_event *)
@@ -823,6 +859,8 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
 	channel->rescind = true;
 	spin_unlock_irqrestore(&channel->lock, flags);
 
+	vmbus_rescind_cleanup(channel);
+
 	if (channel->device_obj) {
 		if (channel->chn_rescind_callback) {
 			channel->chn_rescind_callback(channel);
@@ -1116,8 +1154,8 @@ int vmbus_request_offers(void)
 	msg->msgtype = CHANNELMSG_REQUESTOFFERS;
 
 
-	ret = vmbus_post_msg(msg,
-			       sizeof(struct vmbus_channel_message_header));
+	ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_message_header),
+			     true);
 	if (ret != 0) {
 		pr_err("Unable to request offers - %d\n", ret);