From 50698d80f8bb1db989b7b9fa433f588fade5e382 Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Mon, 27 Feb 2017 10:26:47 -0800
Subject: netvsc: don't overload variable in same function

There are two variables named packet in the same function. One is the
metadata descriptor from host (vmpacket_descriptor) and the other is
the control block in the skb used to hold metadata from send.
Change name to avoid possible confusion and bugs.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/netvsc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index d35ebd993b38..5dedbc36c326 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -600,9 +600,9 @@ static inline void netvsc_free_send_slot(struct netvsc_device *net_device,
 static void netvsc_send_tx_complete(struct netvsc_device *net_device,
 				    struct vmbus_channel *incoming_channel,
 				    struct hv_device *device,
-				    struct vmpacket_descriptor *packet)
+				    const struct vmpacket_descriptor *desc)
 {
-	struct sk_buff *skb = (struct sk_buff *)(unsigned long)packet->trans_id;
+	struct sk_buff *skb = (struct sk_buff *)(unsigned long)desc->trans_id;
 	struct net_device *ndev = hv_get_drvdata(device);
 	struct net_device_context *net_device_ctx = netdev_priv(ndev);
 	struct vmbus_channel *channel = device->channel;
-- 
cgit v1.2.3


From f3dd3f4797652c311df9c074436d420f1ad3566e Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Mon, 27 Feb 2017 10:26:48 -0800
Subject: vmbus: introduce in-place packet iterator

This is mostly just a refactoring of previous functions
(get_pkt_next_raw, put_pkt_raw and commit_rd_index) to make it easier
to use for other drivers and NAPI.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/hv/ring_buffer.c    | 94 +++++++++++++++++++++++++++++++++++++++++++-
 drivers/net/hyperv/netvsc.c | 34 +++++-----------
 include/linux/hyperv.h      | 96 ++++++++++++++-------------------------------
 3 files changed, 133 insertions(+), 91 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 87799e81af97..c3f1a9e33cef 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -32,6 +32,8 @@
 
 #include "hyperv_vmbus.h"
 
+#define VMBUS_PKT_TRAILER	8
+
 /*
  * When we write to the ring buffer, check if the host needs to
  * be signaled. Here is the details of this protocol:
@@ -336,6 +338,12 @@ int hv_ringbuffer_write(struct vmbus_channel *channel,
 	return 0;
 }
 
+static inline void
+init_cached_read_index(struct hv_ring_buffer_info *rbi)
+{
+	rbi->cached_read_index = rbi->ring_buffer->read_index;
+}
+
 int hv_ringbuffer_read(struct vmbus_channel *channel,
 		       void *buffer, u32 buflen, u32 *buffer_actual_len,
 		       u64 *requestid, bool raw)
@@ -366,7 +374,8 @@ int hv_ringbuffer_read(struct vmbus_channel *channel,
 		return ret;
 	}
 
-	init_cached_read_index(channel);
+	init_cached_read_index(inring_info);
+
 	next_read_location = hv_get_next_read_location(inring_info);
 	next_read_location = hv_copyfrom_ringbuffer(inring_info, &desc,
 						    sizeof(desc),
@@ -410,3 +419,86 @@ int hv_ringbuffer_read(struct vmbus_channel *channel,
 
 	return ret;
 }
+
+/*
+ * Determine number of bytes available in ring buffer after
+ * the current iterator (priv_read_index) location.
+ *
+ * This is similar to hv_get_bytes_to_read but with private
+ * read index instead.
+ */
+static u32 hv_pkt_iter_avail(const struct hv_ring_buffer_info *rbi)
+{
+	u32 priv_read_loc = rbi->priv_read_index;
+	u32 write_loc = READ_ONCE(rbi->ring_buffer->write_index);
+
+	if (write_loc >= priv_read_loc)
+		return write_loc - priv_read_loc;
+	else
+		return (rbi->ring_datasize - priv_read_loc) + write_loc;
+}
+
+/*
+ * Get first vmbus packet from ring buffer after read_index
+ *
+ * If ring buffer is empty, returns NULL and no other action needed.
+ */
+struct vmpacket_descriptor *hv_pkt_iter_first(struct vmbus_channel *channel)
+{
+	struct hv_ring_buffer_info *rbi = &channel->inbound;
+
+	/* set state for later hv_signal_on_read() */
+	init_cached_read_index(rbi);
+
+	if (hv_pkt_iter_avail(rbi) < sizeof(struct vmpacket_descriptor))
+		return NULL;
+
+	return hv_get_ring_buffer(rbi) + rbi->priv_read_index;
+}
+EXPORT_SYMBOL_GPL(hv_pkt_iter_first);
+
+/*
+ * Get next vmbus packet from ring buffer.
+ *
+ * Advances the current location (priv_read_index) and checks for more
+ * data. If the end of the ring buffer is reached, then return NULL.
+ */
+struct vmpacket_descriptor *
+__hv_pkt_iter_next(struct vmbus_channel *channel,
+		   const struct vmpacket_descriptor *desc)
+{
+	struct hv_ring_buffer_info *rbi = &channel->inbound;
+	u32 packetlen = desc->len8 << 3;
+	u32 dsize = rbi->ring_datasize;
+
+	/* bump offset to next potential packet */
+	rbi->priv_read_index += packetlen + VMBUS_PKT_TRAILER;
+	if (rbi->priv_read_index >= dsize)
+		rbi->priv_read_index -= dsize;
+
+	/* more data? */
+	if (hv_pkt_iter_avail(rbi) < sizeof(struct vmpacket_descriptor))
+		return NULL;
+	else
+		return hv_get_ring_buffer(rbi) + rbi->priv_read_index;
+}
+EXPORT_SYMBOL_GPL(__hv_pkt_iter_next);
+
+/*
+ * Update host ring buffer after iterating over packets.
+ */
+void hv_pkt_iter_close(struct vmbus_channel *channel)
+{
+	struct hv_ring_buffer_info *rbi = &channel->inbound;
+
+	/*
+	 * Make sure all reads are done before we update the read index since
+	 * the writer may start writing to the read area once the read index
+	 * is updated.
+	 */
+	virt_rmb();
+	rbi->ring_buffer->read_index = rbi->priv_read_index;
+
+	hv_signal_on_read(channel);
+}
+EXPORT_SYMBOL_GPL(hv_pkt_iter_close);
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 5dedbc36c326..3681fb59bdbe 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -647,14 +647,11 @@ static void netvsc_send_tx_complete(struct netvsc_device *net_device,
 static void netvsc_send_completion(struct netvsc_device *net_device,
 				   struct vmbus_channel *incoming_channel,
 				   struct hv_device *device,
-				   struct vmpacket_descriptor *packet)
+				   const struct vmpacket_descriptor *desc)
 {
-	struct nvsp_message *nvsp_packet;
+	struct nvsp_message *nvsp_packet = hv_pkt_data(desc);
 	struct net_device *ndev = hv_get_drvdata(device);
 
-	nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
-					      (packet->offset8 << 3));
-
 	switch (nvsp_packet->hdr.msg_type) {
 	case NVSP_MSG_TYPE_INIT_COMPLETE:
 	case NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE:
@@ -668,7 +665,7 @@ static void netvsc_send_completion(struct netvsc_device *net_device,
 
 	case NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE:
 		netvsc_send_tx_complete(net_device, incoming_channel,
-					device, packet);
+					device, desc);
 		break;
 
 	default:
@@ -1071,9 +1068,11 @@ static void netvsc_receive(struct net_device *ndev,
 		   struct net_device_context *net_device_ctx,
 		   struct hv_device *device,
 		   struct vmbus_channel *channel,
-		   struct vmtransfer_page_packet_header *vmxferpage_packet,
+		   const struct vmpacket_descriptor *desc,
 		   struct nvsp_message *nvsp)
 {
+	const struct vmtransfer_page_packet_header *vmxferpage_packet
+		= container_of(desc, const struct vmtransfer_page_packet_header, d);
 	char *recv_buf = net_device->recv_buf;
 	u32 status = NVSP_STAT_SUCCESS;
 	int i;
@@ -1185,12 +1184,10 @@ static void netvsc_process_raw_pkt(struct hv_device *device,
 				   struct netvsc_device *net_device,
 				   struct net_device *ndev,
 				   u64 request_id,
-				   struct vmpacket_descriptor *desc)
+				   const struct vmpacket_descriptor *desc)
 {
 	struct net_device_context *net_device_ctx = netdev_priv(ndev);
-	struct nvsp_message *nvmsg
-		= (struct nvsp_message *)((unsigned long)desc
-					  + (desc->offset8 << 3));
+	struct nvsp_message *nvmsg = hv_pkt_data(desc);
 
 	switch (desc->type) {
 	case VM_PKT_COMP:
@@ -1199,9 +1196,7 @@ static void netvsc_process_raw_pkt(struct hv_device *device,
 
 	case VM_PKT_DATA_USING_XFER_PAGES:
 		netvsc_receive(ndev, net_device, net_device_ctx,
-			       device, channel,
-			       (struct vmtransfer_page_packet_header *)desc,
-			       nvmsg);
+			       device, channel, desc, nvmsg);
 		break;
 
 	case VM_PKT_DATA_INBAND:
@@ -1223,7 +1218,6 @@ void netvsc_channel_cb(void *context)
 	struct netvsc_device *net_device;
 	struct vmpacket_descriptor *desc;
 	struct net_device *ndev;
-	bool need_to_commit = false;
 
 	if (channel->primary_channel != NULL)
 		device = channel->primary_channel->device_obj;
@@ -1239,20 +1233,12 @@ void netvsc_channel_cb(void *context)
 	    netvsc_channel_idle(net_device, q_idx))
 		return;
 
-	/* commit_rd_index() -> hv_signal_on_read() needs this. */
-	init_cached_read_index(channel);
-
-	while ((desc = get_next_pkt_raw(channel)) != NULL) {
+	foreach_vmbus_pkt(desc, channel) {
 		netvsc_process_raw_pkt(device, channel, net_device,
 				       ndev, desc->trans_id, desc);
 
-		put_pkt_raw(channel, desc);
-		need_to_commit = true;
 	}
 
-	if (need_to_commit)
-		commit_rd_index(channel);
-
 	netvsc_chk_recv_comp(net_device, channel, q_idx);
 }
 
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 62bbf3c1aa4a..36162485d663 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -1504,14 +1504,6 @@ static inline  void hv_signal_on_read(struct vmbus_channel *channel)
 	return;
 }
 
-static inline void
-init_cached_read_index(struct vmbus_channel *channel)
-{
-	struct hv_ring_buffer_info *rbi = &channel->inbound;
-
-	rbi->cached_read_index = rbi->ring_buffer->read_index;
-}
-
 /*
  * Mask off host interrupt callback notifications
  */
@@ -1545,76 +1537,48 @@ static inline u32 hv_end_read(struct hv_ring_buffer_info *rbi)
 /*
  * An API to support in-place processing of incoming VMBUS packets.
  */
-#define VMBUS_PKT_TRAILER	8
 
-static inline struct vmpacket_descriptor *
-get_next_pkt_raw(struct vmbus_channel *channel)
+/* Get data payload associated with descriptor */
+static inline void *hv_pkt_data(const struct vmpacket_descriptor *desc)
 {
-	struct hv_ring_buffer_info *ring_info = &channel->inbound;
-	u32 priv_read_loc = ring_info->priv_read_index;
-	void *ring_buffer = hv_get_ring_buffer(ring_info);
-	u32 dsize = ring_info->ring_datasize;
-	/*
-	 * delta is the difference between what is available to read and
-	 * what was already consumed in place. We commit read index after
-	 * the whole batch is processed.
-	 */
-	u32 delta = priv_read_loc >= ring_info->ring_buffer->read_index ?
-		priv_read_loc - ring_info->ring_buffer->read_index :
-		(dsize - ring_info->ring_buffer->read_index) + priv_read_loc;
-	u32 bytes_avail_toread = (hv_get_bytes_to_read(ring_info) - delta);
-
-	if (bytes_avail_toread < sizeof(struct vmpacket_descriptor))
-		return NULL;
-
-	return ring_buffer + priv_read_loc;
+	return (void *)((unsigned long)desc + (desc->offset8 << 3));
 }
 
-/*
- * A helper function to step through packets "in-place"
- * This API is to be called after each successful call
- * get_next_pkt_raw().
- */
-static inline void put_pkt_raw(struct vmbus_channel *channel,
-				struct vmpacket_descriptor *desc)
+/* Get data size associated with descriptor */
+static inline u32 hv_pkt_datalen(const struct vmpacket_descriptor *desc)
 {
-	struct hv_ring_buffer_info *ring_info = &channel->inbound;
-	u32 packetlen = desc->len8 << 3;
-	u32 dsize = ring_info->ring_datasize;
-
-	/*
-	 * Include the packet trailer.
-	 */
-	ring_info->priv_read_index += packetlen + VMBUS_PKT_TRAILER;
-	ring_info->priv_read_index %= dsize;
+	return (desc->len8 << 3) - (desc->offset8 << 3);
 }
 
+
+struct vmpacket_descriptor *
+hv_pkt_iter_first(struct vmbus_channel *channel);
+
+struct vmpacket_descriptor *
+__hv_pkt_iter_next(struct vmbus_channel *channel,
+		   const struct vmpacket_descriptor *pkt);
+
+void hv_pkt_iter_close(struct vmbus_channel *channel);
+
 /*
- * This call commits the read index and potentially signals the host.
- * Here is the pattern for using the "in-place" consumption APIs:
- *
- * init_cached_read_index();
- *
- * while (get_next_pkt_raw() {
- *	process the packet "in-place";
- *	put_pkt_raw();
- * }
- * if (packets processed in place)
- *	commit_rd_index();
+ * Get next packet descriptor from iterator
+ * If at end of list, return NULL and update host.
  */
-static inline void commit_rd_index(struct vmbus_channel *channel)
+static inline struct vmpacket_descriptor *
+hv_pkt_iter_next(struct vmbus_channel *channel,
+		 const struct vmpacket_descriptor *pkt)
 {
-	struct hv_ring_buffer_info *ring_info = &channel->inbound;
-	/*
-	 * Make sure all reads are done before we update the read index since
-	 * the writer may start writing to the read area once the read index
-	 * is updated.
-	 */
-	virt_rmb();
-	ring_info->ring_buffer->read_index = ring_info->priv_read_index;
+	struct vmpacket_descriptor *nxt;
+
+	nxt = __hv_pkt_iter_next(channel, pkt);
+	if (!nxt)
+		hv_pkt_iter_close(channel);
 
-	hv_signal_on_read(channel);
+	return nxt;
 }
 
+#define foreach_vmbus_pkt(pkt, channel) \
+	for (pkt = hv_pkt_iter_first(channel); pkt; \
+	    pkt = hv_pkt_iter_next(channel, pkt))
 
 #endif /* _HYPERV_H */
-- 
cgit v1.2.3


From 15a863bf7436124e799ba175a801e25f7b57191e Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Mon, 27 Feb 2017 10:26:49 -0800
Subject: netvsc: implement NAPI

Use NAPI (softirq), to handle receive packets and send completions.
Previously this was handled by tasklet.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/hyperv_net.h   |   2 +
 drivers/net/hyperv/netvsc.c       | 140 ++++++++++++++++++++++++++------------
 drivers/net/hyperv/netvsc_drv.c   |   5 --
 drivers/net/hyperv/rndis_filter.c |   2 +
 4 files changed, 102 insertions(+), 47 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index d3e73ac158ae..7433b164e513 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -196,6 +196,7 @@ int netvsc_recv_callback(struct net_device *net,
 			 const struct ndis_tcp_ip_checksum_info *csum_info,
 			 const struct ndis_pkt_8021q_info *vlan);
 void netvsc_channel_cb(void *context);
+int netvsc_poll(struct napi_struct *napi, int budget);
 int rndis_filter_open(struct netvsc_device *nvdev);
 int rndis_filter_close(struct netvsc_device *nvdev);
 int rndis_filter_device_add(struct hv_device *dev,
@@ -720,6 +721,7 @@ struct net_device_context {
 /* Per channel data */
 struct netvsc_channel {
 	struct vmbus_channel *channel;
+	struct napi_struct napi;
 	struct multi_send_data msd;
 	struct multi_recv_comp mrc;
 	atomic_t queue_sends;
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 3681fb59bdbe..b1328cef9d5a 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -556,6 +556,7 @@ void netvsc_device_remove(struct hv_device *device)
 	struct net_device *ndev = hv_get_drvdata(device);
 	struct net_device_context *net_device_ctx = netdev_priv(ndev);
 	struct netvsc_device *net_device = net_device_ctx->nvdev;
+	int i;
 
 	netvsc_disconnect_vsp(device);
 
@@ -570,6 +571,9 @@ void netvsc_device_remove(struct hv_device *device)
 	/* Now, we can close the channel safely */
 	vmbus_close(device->channel);
 
+	for (i = 0; i < VRSS_CHANNEL_MAX; i++)
+		napi_disable(&net_device->chan_table[0].napi);
+
 	/* Release all resources */
 	free_netvsc_device(net_device);
 }
@@ -1063,7 +1067,7 @@ static inline struct recv_comp_data *get_recv_comp_slot(
 	return rcd;
 }
 
-static void netvsc_receive(struct net_device *ndev,
+static int netvsc_receive(struct net_device *ndev,
 		   struct netvsc_device *net_device,
 		   struct net_device_context *net_device_ctx,
 		   struct hv_device *device,
@@ -1073,20 +1077,19 @@ static void netvsc_receive(struct net_device *ndev,
 {
 	const struct vmtransfer_page_packet_header *vmxferpage_packet
 		= container_of(desc, const struct vmtransfer_page_packet_header, d);
+	u16 q_idx = channel->offermsg.offer.sub_channel_index;
 	char *recv_buf = net_device->recv_buf;
 	u32 status = NVSP_STAT_SUCCESS;
 	int i;
 	int count = 0;
 	int ret;
-	struct recv_comp_data *rcd;
-	u16 q_idx = channel->offermsg.offer.sub_channel_index;
 
 	/* Make sure this is a valid nvsp packet */
 	if (unlikely(nvsp->hdr.msg_type != NVSP_MSG1_TYPE_SEND_RNDIS_PKT)) {
 		netif_err(net_device_ctx, rx_err, ndev,
 			  "Unknown nvsp packet type received %u\n",
 			  nvsp->hdr.msg_type);
-		return;
+		return 0;
 	}
 
 	if (unlikely(vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID)) {
@@ -1094,7 +1097,7 @@ static void netvsc_receive(struct net_device *ndev,
 			  "Invalid xfer page set id - expecting %x got %x\n",
 			  NETVSC_RECEIVE_BUFFER_ID,
 			  vmxferpage_packet->xfer_pageset_id);
-		return;
+		return 0;
 	}
 
 	count = vmxferpage_packet->range_cnt;
@@ -1110,26 +1113,26 @@ static void netvsc_receive(struct net_device *ndev,
 					      channel, data, buflen);
 	}
 
-	if (!net_device->chan_table[q_idx].mrc.buf) {
+	if (net_device->chan_table[q_idx].mrc.buf) {
+		struct recv_comp_data *rcd;
+
+		rcd = get_recv_comp_slot(net_device, channel, q_idx);
+		if (rcd) {
+			rcd->tid = vmxferpage_packet->d.trans_id;
+			rcd->status = status;
+		} else {
+			netdev_err(ndev, "Recv_comp full buf q:%hd, tid:%llx\n",
+				   q_idx, vmxferpage_packet->d.trans_id);
+		}
+	} else {
 		ret = netvsc_send_recv_completion(channel,
 						  vmxferpage_packet->d.trans_id,
 						  status);
 		if (ret)
 			netdev_err(ndev, "Recv_comp q:%hd, tid:%llx, err:%d\n",
 				   q_idx, vmxferpage_packet->d.trans_id, ret);
-		return;
 	}
-
-	rcd = get_recv_comp_slot(net_device, channel, q_idx);
-
-	if (!rcd) {
-		netdev_err(ndev, "Recv_comp full buf q:%hd, tid:%llx\n",
-			   q_idx, vmxferpage_packet->d.trans_id);
-		return;
-	}
-
-	rcd->tid = vmxferpage_packet->d.trans_id;
-	rcd->status = status;
+	return count;
 }
 
 static void netvsc_send_table(struct hv_device *hdev,
@@ -1179,12 +1182,12 @@ static inline void netvsc_receive_inband(struct hv_device *hdev,
 	}
 }
 
-static void netvsc_process_raw_pkt(struct hv_device *device,
-				   struct vmbus_channel *channel,
-				   struct netvsc_device *net_device,
-				   struct net_device *ndev,
-				   u64 request_id,
-				   const struct vmpacket_descriptor *desc)
+static int netvsc_process_raw_pkt(struct hv_device *device,
+				  struct vmbus_channel *channel,
+				  struct netvsc_device *net_device,
+				  struct net_device *ndev,
+				  u64 request_id,
+				  const struct vmpacket_descriptor *desc)
 {
 	struct net_device_context *net_device_ctx = netdev_priv(ndev);
 	struct nvsp_message *nvmsg = hv_pkt_data(desc);
@@ -1195,8 +1198,8 @@ static void netvsc_process_raw_pkt(struct hv_device *device,
 		break;
 
 	case VM_PKT_DATA_USING_XFER_PAGES:
-		netvsc_receive(ndev, net_device, net_device_ctx,
-			       device, channel, desc, nvmsg);
+		return netvsc_receive(ndev, net_device, net_device_ctx,
+				      device, channel, desc, nvmsg);
 		break;
 
 	case VM_PKT_DATA_INBAND:
@@ -1208,22 +1211,64 @@ static void netvsc_process_raw_pkt(struct hv_device *device,
 			   desc->type, request_id);
 		break;
 	}
+
+	return 0;
+}
+
+static struct hv_device *netvsc_channel_to_device(struct vmbus_channel *channel)
+{
+	struct vmbus_channel *primary = channel->primary_channel;
+
+	return primary ? primary->device_obj : channel->device_obj;
+}
+
+int netvsc_poll(struct napi_struct *napi, int budget)
+{
+	struct netvsc_channel *nvchan
+		= container_of(napi, struct netvsc_channel, napi);
+	struct vmbus_channel *channel = nvchan->channel;
+	struct hv_device *device = netvsc_channel_to_device(channel);
+	u16 q_idx = channel->offermsg.offer.sub_channel_index;
+	struct net_device *ndev = hv_get_drvdata(device);
+	struct netvsc_device *net_device = net_device_to_netvsc_device(ndev);
+	const struct vmpacket_descriptor *desc;
+	int work_done = 0;
+
+	desc = hv_pkt_iter_first(channel);
+	while (desc) {
+		int count;
+
+		count = netvsc_process_raw_pkt(device, channel, net_device,
+					       ndev, desc->trans_id, desc);
+		work_done += count;
+		desc = __hv_pkt_iter_next(channel, desc);
+
+		/* If receive packet budget is exhausted, reschedule */
+		if (work_done >= budget) {
+			work_done = budget;
+			break;
+		}
+	}
+	hv_pkt_iter_close(channel);
+
+	/* If ring is empty and NAPI is not doing polling */
+	if (work_done < budget &&
+	    napi_complete_done(napi, work_done) &&
+	    hv_end_read(&channel->inbound) != 0)
+		napi_reschedule(napi);
+
+	netvsc_chk_recv_comp(net_device, channel, q_idx);
+	return work_done;
 }
 
 void netvsc_channel_cb(void *context)
 {
 	struct vmbus_channel *channel = context;
+	struct hv_device *device = netvsc_channel_to_device(channel);
 	u16 q_idx = channel->offermsg.offer.sub_channel_index;
-	struct hv_device *device;
 	struct netvsc_device *net_device;
-	struct vmpacket_descriptor *desc;
 	struct net_device *ndev;
 
-	if (channel->primary_channel != NULL)
-		device = channel->primary_channel->device_obj;
-	else
-		device = channel->device_obj;
-
 	ndev = hv_get_drvdata(device);
 	if (unlikely(!ndev))
 		return;
@@ -1233,13 +1278,9 @@ void netvsc_channel_cb(void *context)
 	    netvsc_channel_idle(net_device, q_idx))
 		return;
 
-	foreach_vmbus_pkt(desc, channel) {
-		netvsc_process_raw_pkt(device, channel, net_device,
-				       ndev, desc->trans_id, desc);
-
-	}
-
-	netvsc_chk_recv_comp(net_device, channel, q_idx);
+	/* disable interupts from host */
+	hv_begin_read(&channel->inbound);
+	napi_schedule(&net_device->chan_table[q_idx].napi);
 }
 
 /*
@@ -1261,6 +1302,11 @@ int netvsc_device_add(struct hv_device *device,
 
 	net_device->ring_size = ring_size;
 
+	/* Because the device uses NAPI, all the interrupt batching and
+	 * control is done via Net softirq, not the channel handling
+	 */
+	set_channel_read_mode(device->channel, HV_CALL_ISR);
+
 	/* Open the channel */
 	ret = vmbus_open(device->channel, ring_size * PAGE_SIZE,
 			 ring_size * PAGE_SIZE, NULL, 0,
@@ -1278,8 +1324,16 @@ int netvsc_device_add(struct hv_device *device,
 	 * chn_table with the default channel to use it before subchannels are
 	 * opened.
 	 */
-	for (i = 0; i < VRSS_CHANNEL_MAX; i++)
-		net_device->chan_table[i].channel = device->channel;
+	for (i = 0; i < VRSS_CHANNEL_MAX; i++) {
+		struct netvsc_channel *nvchan = &net_device->chan_table[i];
+
+		nvchan->channel = device->channel;
+		netif_napi_add(ndev, &nvchan->napi,
+			       netvsc_poll, NAPI_POLL_WEIGHT);
+	}
+
+	/* Enable NAPI handler for init callbacks */
+	napi_enable(&net_device->chan_table[0].napi);
 
 	/* Writing nvdev pointer unlocks netvsc_send(), make sure chn_table is
 	 * populated.
@@ -1299,6 +1353,8 @@ int netvsc_device_add(struct hv_device *device,
 	return ret;
 
 close:
+	napi_disable(&net_device->chan_table[0].napi);
+
 	/* Now, we can close the channel safely */
 	vmbus_close(device->channel);
 
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index bc05c895d958..65d738b783cb 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -690,11 +690,6 @@ int netvsc_recv_callback(struct net_device *net,
 		++rx_stats->multicast;
 	u64_stats_update_end(&rx_stats->syncp);
 
-	/*
-	 * Pass the skb back up. Network stack will deallocate the skb when it
-	 * is done.
-	 * TODO - use NAPI?
-	 */
 	netif_receive_skb(skb);
 	rcu_read_unlock();
 
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index 19356f56b7b1..d7b6311e6c19 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1012,6 +1012,8 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc)
 	if (ret == 0)
 		nvscdev->chan_table[chn_index].channel = new_sc;
 
+	napi_enable(&nvscdev->chan_table[chn_index].napi);
+
 	spin_lock_irqsave(&nvscdev->sc_lock, flags);
 	nvscdev->num_sc_offered--;
 	spin_unlock_irqrestore(&nvscdev->sc_lock, flags);
-- 
cgit v1.2.3


From 0d6dd35784e76bc3e052ffa13c6839d5c9bcb449 Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Thu, 9 Mar 2017 15:04:14 -0800
Subject: netvsc: need napi scheduled during removal

Since rndis_halt_device waits until all outstanding sends and
receives are completed. Netvsc device needs to still schedule
NAPI to see those completions.

Fixes: 2506b1dc4bbe ("netvsc: implement NAPI")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/netvsc.c | 16 ++--------------
 1 file changed, 2 insertions(+), 14 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index b1328cef9d5a..0e0c757c1681 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -91,15 +91,6 @@ static void free_netvsc_device(struct netvsc_device *nvdev)
 }
 
 
-static inline bool netvsc_channel_idle(const struct netvsc_device *net_device,
-				       u16 q_idx)
-{
-	const struct netvsc_channel *nvchan = &net_device->chan_table[q_idx];
-
-	return atomic_read(&net_device->num_outstanding_recvs) == 0 &&
-		atomic_read(&nvchan->queue_sends) == 0;
-}
-
 static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
 {
 	struct netvsc_device *net_device = hv_device_to_netvsc_device(device);
@@ -1273,13 +1264,10 @@ void netvsc_channel_cb(void *context)
 	if (unlikely(!ndev))
 		return;
 
-	net_device = net_device_to_netvsc_device(ndev);
-	if (unlikely(net_device->destroy) &&
-	    netvsc_channel_idle(net_device, q_idx))
-		return;
-
 	/* disable interupts from host */
 	hv_begin_read(&channel->inbound);
+
+	net_device = net_device_to_netvsc_device(ndev);
 	napi_schedule(&net_device->chan_table[q_idx].napi);
 }
 
-- 
cgit v1.2.3


From 79cd874c96b38694fb2b4ee3850f6fbbc3015439 Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Thu, 9 Mar 2017 15:04:15 -0800
Subject: netvsc: fix hang on netvsc module removal

The code in netvsc_device_remove was incorrectly calling napi_disable
repeatedly on the same element. This would cause attempts
to remove netvsc module to hang.

Fixes: 2506b1dc4bbe ("netvsc: implement NAPI")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/netvsc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 0e0c757c1681..8f9aeec2ce0f 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -562,8 +562,8 @@ void netvsc_device_remove(struct hv_device *device)
 	/* Now, we can close the channel safely */
 	vmbus_close(device->channel);
 
-	for (i = 0; i < VRSS_CHANNEL_MAX; i++)
-		napi_disable(&net_device->chan_table[0].napi);
+	for (i = 0; i < net_device->num_chn; i++)
+		napi_disable(&net_device->chan_table[i].napi);
 
 	/* Release all resources */
 	free_netvsc_device(net_device);
-- 
cgit v1.2.3


From 6de38af611ca81a970965c06231cd2d5f30b2566 Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Thu, 16 Mar 2017 16:12:37 -0700
Subject: netvsc: avoid race with callback

Change the argument to channel callback from the channel pointer
to the internal data structure containing per-channel info.
This avoids any possible races when callback happens during
initialization and makes IRQ code simpler.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/netvsc.c       | 18 +++++-------------
 drivers/net/hyperv/rndis_filter.c | 15 ++++++++++-----
 2 files changed, 15 insertions(+), 18 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 0e71164849dd..0a2e9bd98d2c 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -1250,21 +1250,12 @@ int netvsc_poll(struct napi_struct *napi, int budget)
 
 void netvsc_channel_cb(void *context)
 {
-	struct vmbus_channel *channel = context;
-	struct hv_device *device = netvsc_channel_to_device(channel);
-	u16 q_idx = channel->offermsg.offer.sub_channel_index;
-	struct netvsc_device *net_device;
-	struct net_device *ndev;
-
-	ndev = hv_get_drvdata(device);
-	if (unlikely(!ndev))
-		return;
+	struct netvsc_channel *nvchan = context;
 
 	/* disable interupts from host */
-	hv_begin_read(&channel->inbound);
+	hv_begin_read(&nvchan->channel->inbound);
 
-	net_device = net_device_to_netvsc_device(ndev);
-	napi_schedule(&net_device->chan_table[q_idx].napi);
+	napi_schedule(&nvchan->napi);
 }
 
 /*
@@ -1294,7 +1285,8 @@ int netvsc_device_add(struct hv_device *device,
 	/* Open the channel */
 	ret = vmbus_open(device->channel, ring_size * PAGE_SIZE,
 			 ring_size * PAGE_SIZE, NULL, 0,
-			 netvsc_channel_cb, device->channel);
+			 netvsc_channel_cb,
+			 net_device->chan_table);
 
 	if (ret != 0) {
 		netdev_err(ndev, "unable to open channel: %d\n", ret);
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index d7b6311e6c19..382b9a62e3c4 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -996,23 +996,28 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc)
 		hv_get_drvdata(new_sc->primary_channel->device_obj);
 	struct netvsc_device *nvscdev = net_device_to_netvsc_device(ndev);
 	u16 chn_index = new_sc->offermsg.offer.sub_channel_index;
-	int ret;
+	struct netvsc_channel *nvchan;
 	unsigned long flags;
+	int ret;
 
 	if (chn_index >= nvscdev->num_chn)
 		return;
 
-	nvscdev->chan_table[chn_index].mrc.buf
+	nvchan = nvscdev->chan_table + chn_index;
+	nvchan->mrc.buf
 		= vzalloc(NETVSC_RECVSLOT_MAX * sizeof(struct recv_comp_data));
 
+	if (!nvchan->mrc.buf)
+		return;
+
 	ret = vmbus_open(new_sc, nvscdev->ring_size * PAGE_SIZE,
 			 nvscdev->ring_size * PAGE_SIZE, NULL, 0,
-			 netvsc_channel_cb, new_sc);
+			 netvsc_channel_cb, nvchan);
 
 	if (ret == 0)
-		nvscdev->chan_table[chn_index].channel = new_sc;
+		nvchan->channel = new_sc;
 
-	napi_enable(&nvscdev->chan_table[chn_index].napi);
+	napi_enable(&nvchan->napi);
 
 	spin_lock_irqsave(&nvscdev->sc_lock, flags);
 	nvscdev->num_sc_offered--;
-- 
cgit v1.2.3


From 262b7f142a50badde4032e925902a0d0ad89eb7f Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Thu, 16 Mar 2017 16:12:38 -0700
Subject: netvsc: add comments about callback's and NAPI

Add some short description of how callback's and NAPI interoperate.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/netvsc.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 0a2e9bd98d2c..989b7cd99380 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -1209,6 +1209,10 @@ static struct hv_device *netvsc_channel_to_device(struct vmbus_channel *channel)
 	return primary ? primary->device_obj : channel->device_obj;
 }
 
+/* Network processing softirq
+ * Process data in incoming ring buffer from host
+ * Stops when ring is empty or budget is met or exceeded.
+ */
 int netvsc_poll(struct napi_struct *napi, int budget)
 {
 	struct netvsc_channel *nvchan
@@ -1238,7 +1242,11 @@ int netvsc_poll(struct napi_struct *napi, int budget)
 	}
 	hv_pkt_iter_close(channel);
 
-	/* If ring is empty and NAPI is not doing polling */
+	/* If budget was not exhausted and
+	 * not doing busy poll
+	 * then re-enable host interrupts
+	 *  and reschedule if ring is not empty.
+	 */
 	if (work_done < budget &&
 	    napi_complete_done(napi, work_done) &&
 	    hv_end_read(&channel->inbound) != 0)
@@ -1248,6 +1256,9 @@ int netvsc_poll(struct napi_struct *napi, int budget)
 	return work_done;
 }
 
+/* Call back when data is available in host ring buffer.
+ * Processing is deferred until network softirq (NAPI)
+ */
 void netvsc_channel_cb(void *context)
 {
 	struct netvsc_channel *nvchan = context;
-- 
cgit v1.2.3


From f4f1c23d6e41f5ee4973a6da65cba1e1c536ec29 Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Wed, 22 Mar 2017 14:50:57 -0700
Subject: netvsc: fix NAPI performance regression

When using NAPI, the single stream performance declined signifcantly
because the poll routine was updating host after every burst
of packets. This excess signalling caused host throttling.

This fix restores the old behavior. Host is only signalled
after the ring has been emptied.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/hyperv_net.h |  1 +
 drivers/net/hyperv/netvsc.c     | 41 ++++++++++++++++++-----------------------
 2 files changed, 19 insertions(+), 23 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index 6b5f75217694..a33f2ee86044 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -723,6 +723,7 @@ struct net_device_context {
 /* Per channel data */
 struct netvsc_channel {
 	struct vmbus_channel *channel;
+	const struct vmpacket_descriptor *desc;
 	struct napi_struct napi;
 	struct multi_send_data msd;
 	struct multi_recv_comp mrc;
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 989b7cd99380..727762d0f13b 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -1173,7 +1173,6 @@ static int netvsc_process_raw_pkt(struct hv_device *device,
 				  struct vmbus_channel *channel,
 				  struct netvsc_device *net_device,
 				  struct net_device *ndev,
-				  u64 request_id,
 				  const struct vmpacket_descriptor *desc)
 {
 	struct net_device_context *net_device_ctx = netdev_priv(ndev);
@@ -1195,7 +1194,7 @@ static int netvsc_process_raw_pkt(struct hv_device *device,
 
 	default:
 		netdev_err(ndev, "unhandled packet type %d, tid %llx\n",
-			   desc->type, request_id);
+			   desc->type, desc->trans_id);
 		break;
 	}
 
@@ -1222,28 +1221,20 @@ int netvsc_poll(struct napi_struct *napi, int budget)
 	u16 q_idx = channel->offermsg.offer.sub_channel_index;
 	struct net_device *ndev = hv_get_drvdata(device);
 	struct netvsc_device *net_device = net_device_to_netvsc_device(ndev);
-	const struct vmpacket_descriptor *desc;
 	int work_done = 0;
 
-	desc = hv_pkt_iter_first(channel);
-	while (desc) {
-		int count;
+	/* If starting a new interval */
+	if (!nvchan->desc)
+		nvchan->desc = hv_pkt_iter_first(channel);
 
-		count = netvsc_process_raw_pkt(device, channel, net_device,
-					       ndev, desc->trans_id, desc);
-		work_done += count;
-		desc = __hv_pkt_iter_next(channel, desc);
-
-		/* If receive packet budget is exhausted, reschedule */
-		if (work_done >= budget) {
-			work_done = budget;
-			break;
-		}
+	while (nvchan->desc && work_done < budget) {
+		work_done += netvsc_process_raw_pkt(device, channel, net_device,
+						    ndev, nvchan->desc);
+		nvchan->desc = hv_pkt_iter_next(channel, nvchan->desc);
 	}
-	hv_pkt_iter_close(channel);
 
-	/* If budget was not exhausted and
-	 * not doing busy poll
+	/* If receive ring was exhausted
+	 * and not doing busy poll
 	 * then re-enable host interrupts
 	 *  and reschedule if ring is not empty.
 	 */
@@ -1253,7 +1244,9 @@ int netvsc_poll(struct napi_struct *napi, int budget)
 		napi_reschedule(napi);
 
 	netvsc_chk_recv_comp(net_device, channel, q_idx);
-	return work_done;
+
+	/* Driver may overshoot since multiple packets per descriptor */
+	return min(work_done, budget);
 }
 
 /* Call back when data is available in host ring buffer.
@@ -1263,10 +1256,12 @@ void netvsc_channel_cb(void *context)
 {
 	struct netvsc_channel *nvchan = context;
 
-	/* disable interupts from host */
-	hv_begin_read(&nvchan->channel->inbound);
+	if (napi_schedule_prep(&nvchan->napi)) {
+		/* disable interupts from host */
+		hv_begin_read(&nvchan->channel->inbound);
 
-	napi_schedule(&nvchan->napi);
+		__napi_schedule(&nvchan->napi);
+	}
 }
 
 /*
-- 
cgit v1.2.3


From 545a8e79bd1cc8774877a26275171a2ec8881c9e Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Wed, 22 Mar 2017 14:51:00 -0700
Subject: netvsc: use RCU to protect inner device structure

The netvsc driver has an internal structure (netvsc_device) which
is created when device is opened and released when device is closed.
And also opened/released when MTU or number of channels change.

Since this is referenced in the receive and transmit path, it is
safer to use RCU to protect/prevent use after free problems.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/hyperv_net.h |  4 ++-
 drivers/net/hyperv/netvsc.c     | 16 +++++++----
 drivers/net/hyperv/netvsc_drv.c | 61 +++++++++++++++++++++++++++++------------
 3 files changed, 57 insertions(+), 24 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index a33f2ee86044..0ade21f95d71 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -686,7 +686,7 @@ struct net_device_context {
 	/* point back to our device context */
 	struct hv_device *device_ctx;
 	/* netvsc_device */
-	struct netvsc_device *nvdev;
+	struct netvsc_device __rcu *nvdev;
 	/* reconfigure work */
 	struct delayed_work dwork;
 	/* last reconfig time */
@@ -780,6 +780,8 @@ struct netvsc_device {
 	atomic_t open_cnt;
 
 	struct netvsc_channel chan_table[VRSS_CHANNEL_MAX];
+
+	struct rcu_head rcu;
 };
 
 static inline struct netvsc_device *
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 727762d0f13b..ab9118d620ab 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -80,8 +80,10 @@ static struct netvsc_device *alloc_net_device(void)
 	return net_device;
 }
 
-static void free_netvsc_device(struct netvsc_device *nvdev)
+static void free_netvsc_device(struct rcu_head *head)
 {
+	struct netvsc_device *nvdev
+		= container_of(head, struct netvsc_device, rcu);
 	int i;
 
 	for (i = 0; i < VRSS_CHANNEL_MAX; i++)
@@ -90,6 +92,10 @@ static void free_netvsc_device(struct netvsc_device *nvdev)
 	kfree(nvdev);
 }
 
+static void free_netvsc_device_rcu(struct netvsc_device *nvdev)
+{
+	call_rcu(&nvdev->rcu, free_netvsc_device);
+}
 
 static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
 {
@@ -551,7 +557,7 @@ void netvsc_device_remove(struct hv_device *device)
 
 	netvsc_disconnect_vsp(device);
 
-	net_device_ctx->nvdev = NULL;
+	RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
 
 	/*
 	 * At this point, no one should be accessing net_device
@@ -566,7 +572,7 @@ void netvsc_device_remove(struct hv_device *device)
 		napi_disable(&net_device->chan_table[i].napi);
 
 	/* Release all resources */
-	free_netvsc_device(net_device);
+	free_netvsc_device_rcu(net_device);
 }
 
 #define RING_AVAIL_PERCENT_HIWATER 20
@@ -1322,7 +1328,7 @@ int netvsc_device_add(struct hv_device *device,
 	 */
 	wmb();
 
-	net_device_ctx->nvdev = net_device;
+	rcu_assign_pointer(net_device_ctx->nvdev, net_device);
 
 	/* Connect with the NetVsp */
 	ret = netvsc_connect_vsp(device);
@@ -1341,7 +1347,7 @@ close:
 	vmbus_close(device->channel);
 
 cleanup:
-	free_netvsc_device(net_device);
+	free_netvsc_device(&net_device->rcu);
 
 	return ret;
 }
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 2f9de2e9f38e..d8a70d07eeec 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -62,7 +62,7 @@ static void do_set_multicast(struct work_struct *w)
 		container_of(w, struct net_device_context, work);
 	struct hv_device *device_obj = ndevctx->device_ctx;
 	struct net_device *ndev = hv_get_drvdata(device_obj);
-	struct netvsc_device *nvdev = ndevctx->nvdev;
+	struct netvsc_device *nvdev = rcu_dereference(ndevctx->nvdev);
 	struct rndis_device *rdev;
 
 	if (!nvdev)
@@ -116,7 +116,7 @@ static int netvsc_open(struct net_device *net)
 static int netvsc_close(struct net_device *net)
 {
 	struct net_device_context *net_device_ctx = netdev_priv(net);
-	struct netvsc_device *nvdev = net_device_ctx->nvdev;
+	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
 	int ret;
 	u32 aread, awrite, i, msec = 10, retry = 0, retry_max = 20;
 	struct vmbus_channel *chn;
@@ -637,9 +637,9 @@ int netvsc_recv_callback(struct net_device *net,
 			 const struct ndis_pkt_8021q_info *vlan)
 {
 	struct net_device_context *net_device_ctx = netdev_priv(net);
-	struct netvsc_device *net_device = net_device_ctx->nvdev;
+	struct netvsc_device *net_device;
 	u16 q_idx = channel->offermsg.offer.sub_channel_index;
-	struct netvsc_channel *nvchan = &net_device->chan_table[q_idx];
+	struct netvsc_channel *nvchan;
 	struct net_device *vf_netdev;
 	struct sk_buff *skb;
 	struct netvsc_stats *rx_stats;
@@ -655,6 +655,11 @@ int netvsc_recv_callback(struct net_device *net,
 	 * interface in the guest.
 	 */
 	rcu_read_lock();
+	net_device = rcu_dereference(net_device_ctx->nvdev);
+	if (unlikely(!net_device))
+		goto drop;
+
+	nvchan = &net_device->chan_table[q_idx];
 	vf_netdev = rcu_dereference(net_device_ctx->vf_netdev);
 	if (vf_netdev && (vf_netdev->flags & IFF_UP))
 		net = vf_netdev;
@@ -663,6 +668,7 @@ int netvsc_recv_callback(struct net_device *net,
 	skb = netvsc_alloc_recv_skb(net, &nvchan->napi,
 				    csum_info, vlan, data, len);
 	if (unlikely(!skb)) {
+drop:
 		++net->stats.rx_dropped;
 		rcu_read_unlock();
 		return NVSP_STAT_FAIL;
@@ -704,7 +710,7 @@ static void netvsc_get_channels(struct net_device *net,
 				struct ethtool_channels *channel)
 {
 	struct net_device_context *net_device_ctx = netdev_priv(net);
-	struct netvsc_device *nvdev = net_device_ctx->nvdev;
+	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
 
 	if (nvdev) {
 		channel->max_combined	= nvdev->max_chn;
@@ -741,7 +747,7 @@ static int netvsc_set_channels(struct net_device *net,
 {
 	struct net_device_context *net_device_ctx = netdev_priv(net);
 	struct hv_device *dev = net_device_ctx->device_ctx;
-	struct netvsc_device *nvdev = net_device_ctx->nvdev;
+	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
 	unsigned int count = channels->combined_count;
 	bool was_running;
 	int ret;
@@ -848,7 +854,7 @@ static int netvsc_set_link_ksettings(struct net_device *dev,
 static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 {
 	struct net_device_context *ndevctx = netdev_priv(ndev);
-	struct netvsc_device *nvdev = ndevctx->nvdev;
+	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
 	struct hv_device *hdev = ndevctx->device_ctx;
 	struct netvsc_device_info device_info;
 	bool was_running;
@@ -897,7 +903,7 @@ static void netvsc_get_stats64(struct net_device *net,
 			       struct rtnl_link_stats64 *t)
 {
 	struct net_device_context *ndev_ctx = netdev_priv(net);
-	struct netvsc_device *nvdev = ndev_ctx->nvdev;
+	struct netvsc_device *nvdev = rcu_dereference(ndev_ctx->nvdev);
 	int i;
 
 	if (!nvdev)
@@ -982,7 +988,10 @@ static const struct {
 static int netvsc_get_sset_count(struct net_device *dev, int string_set)
 {
 	struct net_device_context *ndc = netdev_priv(dev);
-	struct netvsc_device *nvdev = ndc->nvdev;
+	struct netvsc_device *nvdev = rcu_dereference(ndc->nvdev);
+
+	if (!nvdev)
+		return -ENODEV;
 
 	switch (string_set) {
 	case ETH_SS_STATS:
@@ -996,13 +1005,16 @@ static void netvsc_get_ethtool_stats(struct net_device *dev,
 				     struct ethtool_stats *stats, u64 *data)
 {
 	struct net_device_context *ndc = netdev_priv(dev);
-	struct netvsc_device *nvdev = ndc->nvdev;
+	struct netvsc_device *nvdev = rcu_dereference(ndc->nvdev);
 	const void *nds = &ndc->eth_stats;
 	const struct netvsc_stats *qstats;
 	unsigned int start;
 	u64 packets, bytes;
 	int i, j;
 
+	if (!nvdev)
+		return;
+
 	for (i = 0; i < NETVSC_GLOBAL_STATS_LEN; i++)
 		data[i] = *(unsigned long *)(nds + netvsc_stats[i].offset);
 
@@ -1031,10 +1043,13 @@ static void netvsc_get_ethtool_stats(struct net_device *dev,
 static void netvsc_get_strings(struct net_device *dev, u32 stringset, u8 *data)
 {
 	struct net_device_context *ndc = netdev_priv(dev);
-	struct netvsc_device *nvdev = ndc->nvdev;
+	struct netvsc_device *nvdev = rcu_dereference(ndc->nvdev);
 	u8 *p = data;
 	int i;
 
+	if (!nvdev)
+		return;
+
 	switch (stringset) {
 	case ETH_SS_STATS:
 		for (i = 0; i < ARRAY_SIZE(netvsc_stats); i++)
@@ -1086,7 +1101,10 @@ netvsc_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info,
 		 u32 *rules)
 {
 	struct net_device_context *ndc = netdev_priv(dev);
-	struct netvsc_device *nvdev = ndc->nvdev;
+	struct netvsc_device *nvdev = rcu_dereference(ndc->nvdev);
+
+	if (!nvdev)
+		return -ENODEV;
 
 	switch (info->cmd) {
 	case ETHTOOL_GRXRINGS:
@@ -1122,10 +1140,13 @@ static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
 			   u8 *hfunc)
 {
 	struct net_device_context *ndc = netdev_priv(dev);
-	struct netvsc_device *ndev = ndc->nvdev;
+	struct netvsc_device *ndev = rcu_dereference(ndc->nvdev);
 	struct rndis_device *rndis_dev = ndev->extension;
 	int i;
 
+	if (!ndev)
+		return -ENODEV;
+
 	if (hfunc)
 		*hfunc = ETH_RSS_HASH_TOP;	/* Toeplitz */
 
@@ -1144,10 +1165,13 @@ static int netvsc_set_rxfh(struct net_device *dev, const u32 *indir,
 			   const u8 *key, const u8 hfunc)
 {
 	struct net_device_context *ndc = netdev_priv(dev);
-	struct netvsc_device *ndev = ndc->nvdev;
+	struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
 	struct rndis_device *rndis_dev = ndev->extension;
 	int i;
 
+	if (!ndev)
+		return -ENODEV;
+
 	if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
 		return -EOPNOTSUPP;
 
@@ -1224,7 +1248,7 @@ static void netvsc_link_change(struct work_struct *w)
 	if (ndev_ctx->start_remove)
 		goto out_unlock;
 
-	net_device = ndev_ctx->nvdev;
+	net_device = rtnl_dereference(ndev_ctx->nvdev);
 	rdev = net_device->extension;
 
 	next_reconfig = ndev_ctx->last_reconfig + LINKCHANGE_INT;
@@ -1365,7 +1389,7 @@ static int netvsc_register_vf(struct net_device *vf_netdev)
 		return NOTIFY_DONE;
 
 	net_device_ctx = netdev_priv(ndev);
-	netvsc_dev = net_device_ctx->nvdev;
+	netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
 	if (!netvsc_dev || rtnl_dereference(net_device_ctx->vf_netdev))
 		return NOTIFY_DONE;
 
@@ -1391,7 +1415,7 @@ static int netvsc_vf_up(struct net_device *vf_netdev)
 		return NOTIFY_DONE;
 
 	net_device_ctx = netdev_priv(ndev);
-	netvsc_dev = net_device_ctx->nvdev;
+	netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
 
 	netdev_info(ndev, "VF up: %s\n", vf_netdev->name);
 
@@ -1425,7 +1449,7 @@ static int netvsc_vf_down(struct net_device *vf_netdev)
 		return NOTIFY_DONE;
 
 	net_device_ctx = netdev_priv(ndev);
-	netvsc_dev = net_device_ctx->nvdev;
+	netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
 
 	netdev_info(ndev, "VF down: %s\n", vf_netdev->name);
 	netvsc_switch_datapath(ndev, false);
@@ -1519,6 +1543,7 @@ static int netvsc_probe(struct hv_device *dev,
 		NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX;
 	net->vlan_features = net->features;
 
+	/* RCU not necessary here, device not registered */
 	nvdev = net_device_ctx->nvdev;
 	netif_set_real_num_tx_queues(net, nvdev->num_chn);
 	netif_set_real_num_rx_queues(net, nvdev->num_chn);
-- 
cgit v1.2.3


From a0be450e19d397e9ff215e32ed31bc51339b460a Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Wed, 22 Mar 2017 14:51:01 -0700
Subject: netvsc: uses RCU instead of removal flag

It is cleaner to use RCU protected pointer (nvdev_ctx->nvdev)
to indicate device is in removed state, rather than having a separate
boolean flag. By using the pointer the context can be checked
by static checkers and dynamic lockdep.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/hyperv_net.h |  3 ---
 drivers/net/hyperv/netvsc.c     |  4 ----
 drivers/net/hyperv/netvsc_drv.c | 34 ++++++++++------------------------
 3 files changed, 10 insertions(+), 31 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index 0ade21f95d71..907f55960ba8 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -708,9 +708,6 @@ struct net_device_context {
 	u32 speed;
 	struct netvsc_ethtool_stats eth_stats;
 
-	/* the device is going away */
-	bool start_remove;
-
 	/* State to manage the associated VF interface. */
 	struct net_device __rcu *vf_netdev;
 
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index ab9118d620ab..1f17d948f9b0 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -605,7 +605,6 @@ static void netvsc_send_tx_complete(struct netvsc_device *net_device,
 {
 	struct sk_buff *skb = (struct sk_buff *)(unsigned long)desc->trans_id;
 	struct net_device *ndev = hv_get_drvdata(device);
-	struct net_device_context *net_device_ctx = netdev_priv(ndev);
 	struct vmbus_channel *channel = device->channel;
 	u16 q_idx = 0;
 	int queue_sends;
@@ -639,7 +638,6 @@ static void netvsc_send_tx_complete(struct netvsc_device *net_device,
 		wake_up(&net_device->wait_drain);
 
 	if (netif_tx_queue_stopped(netdev_get_tx_queue(ndev, q_idx)) &&
-	    !net_device_ctx->start_remove &&
 	    (hv_ringbuf_avail_percent(&channel->outbound) > RING_AVAIL_PERCENT_HIWATER ||
 	     queue_sends < 1))
 		netif_tx_wake_queue(netdev_get_tx_queue(ndev, q_idx));
@@ -1326,8 +1324,6 @@ int netvsc_device_add(struct hv_device *device,
 	/* Writing nvdev pointer unlocks netvsc_send(), make sure chn_table is
 	 * populated.
 	 */
-	wmb();
-
 	rcu_assign_pointer(net_device_ctx->nvdev, net_device);
 
 	/* Connect with the NetVsp */
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index d8a70d07eeec..eb7ae79d47bb 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -760,7 +760,7 @@ static int netvsc_set_channels(struct net_device *net,
 	if (count > net->num_tx_queues || count > net->num_rx_queues)
 		return -EINVAL;
 
-	if (net_device_ctx->start_remove || !nvdev || nvdev->destroy)
+	if (!nvdev || nvdev->destroy)
 		return -ENODEV;
 
 	if (nvdev->nvsp_version < NVSP_PROTOCOL_VERSION_5)
@@ -776,7 +776,6 @@ static int netvsc_set_channels(struct net_device *net,
 			return ret;
 	}
 
-	net_device_ctx->start_remove = true;
 	rndis_filter_device_remove(dev, nvdev);
 
 	ret = netvsc_set_queues(net, dev, count);
@@ -785,8 +784,6 @@ static int netvsc_set_channels(struct net_device *net,
 	else
 		netvsc_set_queues(net, dev, nvdev->num_chn);
 
-	net_device_ctx->start_remove = false;
-
 	if (was_running)
 		ret = netvsc_open(net);
 
@@ -860,7 +857,7 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 	bool was_running;
 	int ret;
 
-	if (ndevctx->start_remove || !nvdev || nvdev->destroy)
+	if (!nvdev || nvdev->destroy)
 		return -ENODEV;
 
 	was_running = netif_running(ndev);
@@ -875,7 +872,6 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 	device_info.num_chn = nvdev->num_chn;
 	device_info.max_num_vrss_chns = nvdev->num_chn;
 
-	ndevctx->start_remove = true;
 	rndis_filter_device_remove(hdev, nvdev);
 
 	/* 'nvdev' has been freed in rndis_filter_device_remove() ->
@@ -888,8 +884,6 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 
 	rndis_filter_device_add(hdev, &device_info);
 
-	ndevctx->start_remove = false;
-
 	if (was_running)
 		ret = netvsc_open(ndev);
 
@@ -1245,10 +1239,10 @@ static void netvsc_link_change(struct work_struct *w)
 	unsigned long flags, next_reconfig, delay;
 
 	rtnl_lock();
-	if (ndev_ctx->start_remove)
+	net_device = rtnl_dereference(ndev_ctx->nvdev);
+	if (!net_device)
 		goto out_unlock;
 
-	net_device = rtnl_dereference(ndev_ctx->nvdev);
 	rdev = net_device->extension;
 
 	next_reconfig = ndev_ctx->last_reconfig + LINKCHANGE_INT;
@@ -1509,8 +1503,6 @@ static int netvsc_probe(struct hv_device *dev,
 
 	hv_set_drvdata(dev, net);
 
-	net_device_ctx->start_remove = false;
-
 	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
 	INIT_WORK(&net_device_ctx->work, do_set_multicast);
 
@@ -1579,26 +1571,20 @@ static int netvsc_remove(struct hv_device *dev)
 
 	ndev_ctx = netdev_priv(net);
 
-	/* Avoid racing with netvsc_change_mtu()/netvsc_set_channels()
-	 * removing the device.
-	 */
-	rtnl_lock();
-	ndev_ctx->start_remove = true;
-	rtnl_unlock();
+	netif_device_detach(net);
 
 	cancel_delayed_work_sync(&ndev_ctx->dwork);
 	cancel_work_sync(&ndev_ctx->work);
 
-	/* Stop outbound asap */
-	netif_tx_disable(net);
-
-	unregister_netdev(net);
-
 	/*
 	 * Call to the vsc driver to let it know that the device is being
-	 * removed
+	 * removed. Also blocks mtu and channel changes.
 	 */
+	rtnl_lock();
 	rndis_filter_device_remove(dev, ndev_ctx->nvdev);
+	rtnl_unlock();
+
+	unregister_netdev(net);
 
 	hv_set_drvdata(dev, NULL);
 
-- 
cgit v1.2.3


From ebc1dcf6008e562a8f88a6b1f4a4705f4d4c4fdd Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Wed, 22 Mar 2017 14:51:04 -0700
Subject: netvsc: eliminate unnecessary skb == NULL checks

Since there already is a special case goto for control messages (skb == NULL)
in netvsc_send, there is no need for later checks in same code path.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/netvsc.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 1f17d948f9b0..e998e2f7a619 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -706,8 +706,7 @@ static u32 netvsc_copy_to_send_buf(struct netvsc_device *net_device,
 		packet->page_buf_cnt;
 
 	/* Add padding */
-	if (skb && skb->xmit_more && remain &&
-	    !packet->cp_partial) {
+	if (skb->xmit_more && remain && !packet->cp_partial) {
 		padding = net_device->pkt_align - remain;
 		rndis_msg->msg_len += padding;
 		packet->total_data_buflen += padding;
@@ -865,9 +864,7 @@ int netvsc_send(struct hv_device *device,
 	if (msdp->pkt)
 		msd_len = msdp->pkt->total_data_buflen;
 
-	try_batch = (skb != NULL) && msd_len > 0 && msdp->count <
-		    net_device->max_pkt;
-
+	try_batch =  msd_len > 0 && msdp->count < net_device->max_pkt;
 	if (try_batch && msd_len + pktlen + net_device->pkt_align <
 	    net_device->send_section_size) {
 		section_index = msdp->pkt->send_buf_index;
@@ -877,7 +874,7 @@ int netvsc_send(struct hv_device *device,
 		section_index = msdp->pkt->send_buf_index;
 		packet->cp_partial = true;
 
-	} else if ((skb != NULL) && pktlen + net_device->pkt_align <
+	} else if (pktlen + net_device->pkt_align <
 		   net_device->send_section_size) {
 		section_index = netvsc_get_next_send_section(net_device);
 		if (section_index != NETVSC_INVALID_INDEX) {
-- 
cgit v1.2.3


From bffb184247bcc783a40a0e123a9a2de3c5b28157 Mon Sep 17 00:00:00 2001
From: "K. Y. Srinivasan" <kys@microsoft.com>
Date: Thu, 6 Apr 2017 14:59:21 -0700
Subject: netvsc: Initialize all channel related state prior to opening the
 channel

Prior to opening the channel we should have all the state setup to handle
interrupts. The current code does not do that; fix the bug. This bug
can result in faults in the interrupt path.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/netvsc.c       | 27 +++++++++++++++------------
 drivers/net/hyperv/rndis_filter.c |  5 +++--
 2 files changed, 18 insertions(+), 14 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index e998e2f7a619..7ab06b338a14 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -1289,6 +1289,21 @@ int netvsc_device_add(struct hv_device *device,
 	 */
 	set_channel_read_mode(device->channel, HV_CALL_ISR);
 
+	/* If we're reopening the device we may have multiple queues, fill the
+	 * chn_table with the default channel to use it before subchannels are
+	 * opened.
+	 * Initialize the channel state before we open;
+	 * we can be interrupted as soon as we open the channel.
+	 */
+
+	for (i = 0; i < VRSS_CHANNEL_MAX; i++) {
+		struct netvsc_channel *nvchan = &net_device->chan_table[i];
+
+		nvchan->channel = device->channel;
+		netif_napi_add(ndev, &nvchan->napi,
+			       netvsc_poll, NAPI_POLL_WEIGHT);
+	}
+
 	/* Open the channel */
 	ret = vmbus_open(device->channel, ring_size * PAGE_SIZE,
 			 ring_size * PAGE_SIZE, NULL, 0,
@@ -1303,18 +1318,6 @@ int netvsc_device_add(struct hv_device *device,
 	/* Channel is opened */
 	netdev_dbg(ndev, "hv_netvsc channel opened successfully\n");
 
-	/* If we're reopening the device we may have multiple queues, fill the
-	 * chn_table with the default channel to use it before subchannels are
-	 * opened.
-	 */
-	for (i = 0; i < VRSS_CHANNEL_MAX; i++) {
-		struct netvsc_channel *nvchan = &net_device->chan_table[i];
-
-		nvchan->channel = device->channel;
-		netif_napi_add(ndev, &nvchan->napi,
-			       netvsc_poll, NAPI_POLL_WEIGHT);
-	}
-
 	/* Enable NAPI handler for init callbacks */
 	napi_enable(&net_device->chan_table[0].napi);
 
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index 983582526b37..1e9445bc4539 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1007,12 +1007,13 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc)
 	 */
 	set_channel_read_mode(new_sc, HV_CALL_ISR);
 
+	/* Set the channel before opening.*/
+	nvchan->channel = new_sc;
+
 	ret = vmbus_open(new_sc, nvscdev->ring_size * PAGE_SIZE,
 			 nvscdev->ring_size * PAGE_SIZE, NULL, 0,
 			 netvsc_channel_cb, nvchan);
 
-	if (ret == 0)
-		nvchan->channel = new_sc;
 
 	napi_enable(&nvchan->napi);
 
-- 
cgit v1.2.3


From f9645430ef5f53ddf0ddd481e9f70f6fce7ccff2 Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Fri, 7 Apr 2017 14:41:19 -0400
Subject: netvsc: use napi_consume_skb

This allows using deferred skb freeing and with NAPI. And get buffer
recycling.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/netvsc.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 7ab06b338a14..fd21d5aab580 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -601,7 +601,8 @@ static inline void netvsc_free_send_slot(struct netvsc_device *net_device,
 static void netvsc_send_tx_complete(struct netvsc_device *net_device,
 				    struct vmbus_channel *incoming_channel,
 				    struct hv_device *device,
-				    const struct vmpacket_descriptor *desc)
+				    const struct vmpacket_descriptor *desc,
+				    int budget)
 {
 	struct sk_buff *skb = (struct sk_buff *)(unsigned long)desc->trans_id;
 	struct net_device *ndev = hv_get_drvdata(device);
@@ -628,7 +629,7 @@ static void netvsc_send_tx_complete(struct netvsc_device *net_device,
 		tx_stats->bytes += packet->total_bytes;
 		u64_stats_update_end(&tx_stats->syncp);
 
-		dev_consume_skb_any(skb);
+		napi_consume_skb(skb, budget);
 	}
 
 	queue_sends =
@@ -646,7 +647,8 @@ static void netvsc_send_tx_complete(struct netvsc_device *net_device,
 static void netvsc_send_completion(struct netvsc_device *net_device,
 				   struct vmbus_channel *incoming_channel,
 				   struct hv_device *device,
-				   const struct vmpacket_descriptor *desc)
+				   const struct vmpacket_descriptor *desc,
+				   int budget)
 {
 	struct nvsp_message *nvsp_packet = hv_pkt_data(desc);
 	struct net_device *ndev = hv_get_drvdata(device);
@@ -664,7 +666,7 @@ static void netvsc_send_completion(struct netvsc_device *net_device,
 
 	case NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE:
 		netvsc_send_tx_complete(net_device, incoming_channel,
-					device, desc);
+					device, desc, budget);
 		break;
 
 	default:
@@ -1174,14 +1176,16 @@ static int netvsc_process_raw_pkt(struct hv_device *device,
 				  struct vmbus_channel *channel,
 				  struct netvsc_device *net_device,
 				  struct net_device *ndev,
-				  const struct vmpacket_descriptor *desc)
+				  const struct vmpacket_descriptor *desc,
+				  int budget)
 {
 	struct net_device_context *net_device_ctx = netdev_priv(ndev);
 	struct nvsp_message *nvmsg = hv_pkt_data(desc);
 
 	switch (desc->type) {
 	case VM_PKT_COMP:
-		netvsc_send_completion(net_device, channel, device, desc);
+		netvsc_send_completion(net_device, channel, device,
+				       desc, budget);
 		break;
 
 	case VM_PKT_DATA_USING_XFER_PAGES:
@@ -1230,7 +1234,7 @@ int netvsc_poll(struct napi_struct *napi, int budget)
 
 	while (nvchan->desc && work_done < budget) {
 		work_done += netvsc_process_raw_pkt(device, channel, net_device,
-						    ndev, nvchan->desc);
+						    ndev, nvchan->desc, budget);
 		nvchan->desc = hv_pkt_iter_next(channel, nvchan->desc);
 	}
 
-- 
cgit v1.2.3


From 73e64fa4f417b22d8d5521999a631ced8e2d442e Mon Sep 17 00:00:00 2001
From: "K. Y. Srinivasan" <kys@microsoft.com>
Date: Wed, 19 Apr 2017 13:53:49 -0700
Subject: netvsc: Deal with rescinded channels correctly

We will not be able to send packets over a channel that has been
rescinded. Make necessary adjustments so we can properly cleanup
even when the channel is rescinded. This issue can be trigerred
in the NIC hot-remove path.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/netvsc.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index fd21d5aab580..967843ba03fa 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -135,6 +135,13 @@ static void netvsc_destroy_buf(struct hv_device *device)
 				       sizeof(struct nvsp_message),
 				       (unsigned long)revoke_packet,
 				       VM_PKT_DATA_INBAND, 0);
+		/* If the failure is because the channel is rescinded;
+		 * ignore the failure since we cannot send on a rescinded
+		 * channel. This would allow us to properly cleanup
+		 * even when the channel is rescinded.
+		 */
+		if (device->channel->rescind)
+			ret = 0;
 		/*
 		 * If we failed here, we might as well return and
 		 * have a leak rather than continue and a bugchk
@@ -195,6 +202,15 @@ static void netvsc_destroy_buf(struct hv_device *device)
 				       sizeof(struct nvsp_message),
 				       (unsigned long)revoke_packet,
 				       VM_PKT_DATA_INBAND, 0);
+
+		/* If the failure is because the channel is rescinded;
+		 * ignore the failure since we cannot send on a rescinded
+		 * channel. This would allow us to properly cleanup
+		 * even when the channel is rescinded.
+		 */
+		if (device->channel->rescind)
+			ret = 0;
+
 		/* If we failed here, we might as well return and
 		 * have a leak rather than continue and a bugchk
 		 */
-- 
cgit v1.2.3


From 76bb5db5c749dfe19d779aac076133e821b859dd Mon Sep 17 00:00:00 2001
From: stephen hemminger <stephen@networkplumber.org>
Date: Wed, 19 Apr 2017 15:22:02 -0700
Subject: netvsc: fix use after free on module removal

The NAPI data structure is embedded in the netvsc_device structure
and is freed when device is closed. There is still a reference
(in NAPI list) to this which causes a crash in netif_napi_del
when device is removed. Fix by managing NAPI instances correctly.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/hyperv/netvsc.c       | 9 +++++----
 drivers/net/hyperv/rndis_filter.c | 9 ++++++---
 2 files changed, 11 insertions(+), 7 deletions(-)

(limited to 'drivers/net/hyperv/netvsc.c')

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 967843ba03fa..f99651c03e0a 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -584,8 +584,9 @@ void netvsc_device_remove(struct hv_device *device)
 	/* Now, we can close the channel safely */
 	vmbus_close(device->channel);
 
+	/* And dissassociate NAPI context from device */
 	for (i = 0; i < net_device->num_chn; i++)
-		napi_disable(&net_device->chan_table[i].napi);
+		netif_napi_del(&net_device->chan_table[i].napi);
 
 	/* Release all resources */
 	free_netvsc_device_rcu(net_device);
@@ -1320,8 +1321,6 @@ int netvsc_device_add(struct hv_device *device,
 		struct netvsc_channel *nvchan = &net_device->chan_table[i];
 
 		nvchan->channel = device->channel;
-		netif_napi_add(ndev, &nvchan->napi,
-			       netvsc_poll, NAPI_POLL_WEIGHT);
 	}
 
 	/* Open the channel */
@@ -1339,6 +1338,8 @@ int netvsc_device_add(struct hv_device *device,
 	netdev_dbg(ndev, "hv_netvsc channel opened successfully\n");
 
 	/* Enable NAPI handler for init callbacks */
+	netif_napi_add(ndev, &net_device->chan_table[0].napi,
+		       netvsc_poll, NAPI_POLL_WEIGHT);
 	napi_enable(&net_device->chan_table[0].napi);
 
 	/* Writing nvdev pointer unlocks netvsc_send(), make sure chn_table is
@@ -1357,7 +1358,7 @@ int netvsc_device_add(struct hv_device *device,
 	return ret;
 
 close:
-	napi_disable(&net_device->chan_table[0].napi);
+	netif_napi_del(&net_device->chan_table[0].napi);
 
 	/* Now, we can close the channel safely */
 	vmbus_close(device->channel);
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index 1e9445bc4539..ab92c3c95951 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1009,13 +1009,16 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc)
 
 	/* Set the channel before opening.*/
 	nvchan->channel = new_sc;
+	netif_napi_add(ndev, &nvchan->napi,
+		       netvsc_poll, NAPI_POLL_WEIGHT);
 
 	ret = vmbus_open(new_sc, nvscdev->ring_size * PAGE_SIZE,
 			 nvscdev->ring_size * PAGE_SIZE, NULL, 0,
 			 netvsc_channel_cb, nvchan);
-
-
-	napi_enable(&nvchan->napi);
+	if (ret == 0)
+		napi_enable(&nvchan->napi);
+	else
+		netdev_err(ndev, "sub channel open failed (%d)\n", ret);
 
 	if (refcount_dec_and_test(&nvscdev->sc_offered))
 		complete(&nvscdev->channel_init_wait);
-- 
cgit v1.2.3