net/hyperv: Add support for jumbo frame up to 64KB

Allow the user set the MTU up to 65536 for Linux guests running on
Hyper-V 2008 R2 or later.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 67 insertions, 17 deletions

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index 287767055125..dec5836ae075 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -456,12 +456,9 @@ struct nvsp_message {
 } __packed;
 
 
+#define NETVSC_MTU 65536
 
-
-/* #define NVSC_MIN_PROTOCOL_VERSION            1 */
-/* #define NVSC_MAX_PROTOCOL_VERSION            1 */
-
-#define NETVSC_RECEIVE_BUFFER_SIZE              (1024*1024)     /* 1MB */
+#define NETVSC_RECEIVE_BUFFER_SIZE              (1024*1024*2)   /* 2MB */
 
 #define NETVSC_RECEIVE_BUFFER_ID                0xcafe
 
@@ -479,6 +476,7 @@ struct netvsc_device {
         u32 nvsp_version;
 
         atomic_t num_outstanding_sends;
+        bool start_remove;
         bool destroy;
         /*
          * List of free preallocated hv_netvsc_packet to represent receive
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 46828b4dd8ab..8965b45ce5a5 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -42,7 +42,7 @@ static struct netvsc_device *alloc_net_device(struct hv_device *device)
         if (!net_device)
                 return NULL;
 
-
+        net_device->start_remove = false;
         net_device->destroy = false;
         net_device->dev = device;
         net_device->ndev = ndev;
@@ -299,7 +299,7 @@ static int negotiate_nvsp_ver(struct hv_device *device,
         /* NVSPv2 only: Send NDIS config */
         memset(init_packet, 0, sizeof(struct nvsp_message));
         init_packet->hdr.msg_type = NVSP_MSG2_TYPE_SEND_NDIS_CONFIG;
-        init_packet->msg.v2_msg.send_ndis_config.mtu = ETH_DATA_LEN;
+        init_packet->msg.v2_msg.send_ndis_config.mtu = net_device->ndev->mtu;
 
         ret = vmbus_sendpacket(device->channel, init_packet,
                                 sizeof(struct nvsp_message),
@@ -464,7 +464,7 @@ static void netvsc_send_completion(struct hv_device *device,
 
                 atomic_dec(&net_device->num_outstanding_sends);
 
-                if (netif_queue_stopped(ndev))
+                if (netif_queue_stopped(ndev) && !net_device->start_remove)
                         netif_wake_queue(ndev);
         } else {
                 netdev_err(ndev, "Unknown send completion packet type- "
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index b7cbd126f20a..462d05f05e84 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -148,10 +148,12 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
         struct net_device_context *net_device_ctx = netdev_priv(net);
         struct hv_netvsc_packet *packet;
         int ret;
-        unsigned int i, num_pages;
+        unsigned int i, num_pages, npg_data;
 
-        /* Add 1 for skb->data and additional one for RNDIS */
-        num_pages = skb_shinfo(skb)->nr_frags + 1 + 1;
+        /* Add multipage for skb->data and additional one for RNDIS */
+        npg_data = (((unsigned long)skb->data + skb_headlen(skb) - 1)
+                >> PAGE_SHIFT) - ((unsigned long)skb->data >> PAGE_SHIFT) + 1;
+        num_pages = skb_shinfo(skb)->nr_frags + npg_data + 1;
 
         /* Allocate a netvsc packet based on # of frags. */
         packet = kzalloc(sizeof(struct hv_netvsc_packet) +
@@ -174,21 +176,36 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
         packet->page_buf_cnt = num_pages;
 
         /* Initialize it from the skb */
-        packet->total_data_buflen       = skb->len;
+        packet->total_data_buflen = skb->len;
 
         /* Start filling in the page buffers starting after RNDIS buffer. */
         packet->page_buf[1].pfn = virt_to_phys(skb->data) >> PAGE_SHIFT;
         packet->page_buf[1].offset
                 = (unsigned long)skb->data & (PAGE_SIZE - 1);
-        packet->page_buf[1].len = skb_headlen(skb);
+        if (npg_data == 1)
+                packet->page_buf[1].len = skb_headlen(skb);
+        else
+                packet->page_buf[1].len = PAGE_SIZE
+                        - packet->page_buf[1].offset;
+
+        for (i = 2; i <= npg_data; i++) {
+                packet->page_buf[i].pfn = virt_to_phys(skb->data
+                        + PAGE_SIZE * (i-1)) >> PAGE_SHIFT;
+                packet->page_buf[i].offset = 0;
+                packet->page_buf[i].len = PAGE_SIZE;
+        }
+        if (npg_data > 1)
+                packet->page_buf[npg_data].len = (((unsigned long)skb->data
+                        + skb_headlen(skb) - 1) & (PAGE_SIZE - 1)) + 1;
 
         /* Additional fragments are after SKB data */
         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
                 const skb_frag_t *f = &skb_shinfo(skb)->frags[i];
 
-                packet->page_buf[i+2].pfn = page_to_pfn(skb_frag_page(f));
-                packet->page_buf[i+2].offset = f->page_offset;
-                packet->page_buf[i+2].len = skb_frag_size(f);
+                packet->page_buf[i+npg_data+1].pfn =
+                        page_to_pfn(skb_frag_page(f));
+                packet->page_buf[i+npg_data+1].offset = f->page_offset;
+                packet->page_buf[i+npg_data+1].len = skb_frag_size(f);
         }
 
         /* Set the completion routine */
@@ -300,6 +317,39 @@ static void netvsc_get_drvinfo(struct net_device *net,
         strcpy(info->fw_version, "N/A");
 }
 
+static int netvsc_change_mtu(struct net_device *ndev, int mtu)
+{
+        struct net_device_context *ndevctx = netdev_priv(ndev);
+        struct hv_device *hdev =  ndevctx->device_ctx;
+        struct netvsc_device *nvdev = hv_get_drvdata(hdev);
+        struct netvsc_device_info device_info;
+        int limit = ETH_DATA_LEN;
+
+        if (nvdev == NULL || nvdev->destroy)
+                return -ENODEV;
+
+        if (nvdev->nvsp_version == NVSP_PROTOCOL_VERSION_2)
+                limit = NETVSC_MTU;
+
+        if (mtu < 68 || mtu > limit)
+                return -EINVAL;
+
+        nvdev->start_remove = true;
+        cancel_delayed_work_sync(&ndevctx->dwork);
+        netif_stop_queue(ndev);
+        rndis_filter_device_remove(hdev);
+
+        ndev->mtu = mtu;
+
+        ndevctx->device_ctx = hdev;
+        hv_set_drvdata(hdev, ndev);
+        device_info.ring_size = ring_size;
+        rndis_filter_device_add(hdev, &device_info);
+        netif_wake_queue(ndev);
+
+        return 0;
+}
+
 static const struct ethtool_ops ethtool_ops = {
         .get_drvinfo    = netvsc_get_drvinfo,
         .get_link       = ethtool_op_get_link,
@@ -310,7 +360,7 @@ static const struct net_device_ops device_ops = {
         .ndo_stop =                     netvsc_close,
         .ndo_start_xmit =               netvsc_start_xmit,
         .ndo_set_rx_mode =              netvsc_set_multicast_list,
-        .ndo_change_mtu =               eth_change_mtu,
+        .ndo_change_mtu =               netvsc_change_mtu,
         .ndo_validate_addr =            eth_validate_addr,
         .ndo_set_mac_address =          eth_mac_addr,
 };
@@ -403,6 +453,8 @@ static int netvsc_remove(struct hv_device *dev)
                 return 0;
         }
 
+        net_device->start_remove = true;
+
         ndev_ctx = netdev_priv(net);
         cancel_delayed_work_sync(&ndev_ctx->dwork);