netvsc: fix warnings reported by lockdep

This includes a bunch of fixups for issues reported by
lockdep.
   * ethtool routines can assume RTNL
   * send is done with RCU lock (and BH disable)
   * avoid refetching internal device struct (netvsc)
     instead pass it as a parameter.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index 4e7ff34..fb62ea6 100644 (file)
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -217,7 +217,8 @@ int rndis_filter_receive(struct net_device *ndev,
                         struct vmbus_channel *channel,
                         void *data, u32 buflen);
 
-int rndis_filter_set_device_mac(struct net_device *ndev, char *mac);
+int rndis_filter_set_device_mac(struct netvsc_device *ndev,
+                               const char *mac);
 
 void netvsc_switch_datapath(struct net_device *nv_dev, bool vf);
 

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 06f39a9..94c00ac 100644 (file)
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -832,7 +832,7 @@ int netvsc_send(struct net_device_context *ndev_ctx,
                struct sk_buff *skb)
 {
        struct netvsc_device *net_device
-               = rcu_dereference_rtnl(ndev_ctx->nvdev);
+               = rcu_dereference_bh(ndev_ctx->nvdev);
        struct hv_device *device = ndev_ctx->device_ctx;
        int ret = 0;
        struct netvsc_channel *nvchan;

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index f1eaf67..a04f2ef 100644 (file)
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -923,6 +923,8 @@ static void netvsc_get_stats64(struct net_device *net,
 
 static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
 {
+       struct net_device_context *ndc = netdev_priv(ndev);
+       struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
        struct sockaddr *addr = p;
        char save_adr[ETH_ALEN];
        unsigned char save_aatype;
@@ -935,7 +937,10 @@ static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
        if (err != 0)
                return err;
 
-       err = rndis_filter_set_device_mac(ndev, addr->sa_data);
+       if (!nvdev)
+               return -ENODEV;
+
+       err = rndis_filter_set_device_mac(nvdev, addr->sa_data);
        if (err != 0) {
                /* roll back to saved MAC */
                memcpy(ndev->dev_addr, save_adr, ETH_ALEN);
@@ -981,7 +986,7 @@ 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 = rcu_dereference(ndc->nvdev);
+       struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
        const void *nds = &ndc->eth_stats;
        const struct netvsc_stats *qstats;
        unsigned int start;
@@ -1019,7 +1024,7 @@ 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 = rcu_dereference(ndc->nvdev);
+       struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
        u8 *p = data;
        int i;
 
@@ -1077,7 +1082,7 @@ 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 = rcu_dereference(ndc->nvdev);
+       struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
 
        if (!nvdev)
                return -ENODEV;
@@ -1127,7 +1132,7 @@ 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 = rcu_dereference(ndc->nvdev);
+       struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
        struct rndis_device *rndis_dev;
        int i;
 

diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index eaa3f0d..bf21ea9 100644 (file)
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -85,14 +85,6 @@ static struct rndis_device *get_rndis_device(void)
        return device;
 }
 
-static struct netvsc_device *
-net_device_to_netvsc_device(struct net_device *ndev)
-{
-       struct net_device_context *net_device_ctx = netdev_priv(ndev);
-
-       return rtnl_dereference(net_device_ctx->nvdev);
-}
-
 static struct rndis_request *get_rndis_request(struct rndis_device *dev,
                                             u32 msg_type,
                                             u32 msg_len)
@@ -252,7 +244,10 @@ static int rndis_filter_send_request(struct rndis_device *dev,
                        pb[0].len;
        }
 
+       rcu_read_lock_bh();
        ret = netvsc_send(net_device_ctx, packet, NULL, &pb, NULL);
+       rcu_read_unlock_bh();
+
        return ret;
 }
 
@@ -452,8 +447,9 @@ int rndis_filter_receive(struct net_device *ndev,
        return 0;
 }
 
-static int rndis_filter_query_device(struct rndis_device *dev, u32 oid,
-                                 void *result, u32 *result_size)
+static int rndis_filter_query_device(struct rndis_device *dev,
+                                    struct netvsc_device *nvdev,
+                                    u32 oid, void *result, u32 *result_size)
 {
        struct rndis_request *request;
        u32 inresult_size = *result_size;
@@ -480,8 +476,6 @@ static int rndis_filter_query_device(struct rndis_device *dev, u32 oid,
        query->dev_vc_handle = 0;
 
        if (oid == OID_TCP_OFFLOAD_HARDWARE_CAPABILITIES) {
-               struct net_device_context *ndevctx = netdev_priv(dev->ndev);
-               struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
                struct ndis_offload *hwcaps;
                u32 nvsp_version = nvdev->nvsp_version;
                u8 ndis_rev;
@@ -550,14 +544,15 @@ cleanup:
 
 /* Get the hardware offload capabilities */
 static int
-rndis_query_hwcaps(struct rndis_device *dev, struct ndis_offload *caps)
+rndis_query_hwcaps(struct rndis_device *dev, struct netvsc_device *net_device,
+                  struct ndis_offload *caps)
 {
        u32 caps_len = sizeof(*caps);
        int ret;
 
        memset(caps, 0, sizeof(*caps));
 
-       ret = rndis_filter_query_device(dev,
+       ret = rndis_filter_query_device(dev, net_device,
                                        OID_TCP_OFFLOAD_HARDWARE_CAPABILITIES,
                                        caps, &caps_len);
        if (ret)
@@ -586,11 +581,12 @@ rndis_query_hwcaps(struct rndis_device *dev, struct ndis_offload *caps)
        return 0;
 }
 
-static int rndis_filter_query_device_mac(struct rndis_device *dev)
+static int rndis_filter_query_device_mac(struct rndis_device *dev,
+                                        struct netvsc_device *net_device)
 {
        u32 size = ETH_ALEN;
 
-       return rndis_filter_query_device(dev,
+       return rndis_filter_query_device(dev, net_device,
                                      RNDIS_OID_802_3_PERMANENT_ADDRESS,
                                      dev->hw_mac_adr, &size);
 }
@@ -598,9 +594,9 @@ static int rndis_filter_query_device_mac(struct rndis_device *dev)
 #define NWADR_STR "NetworkAddress"
 #define NWADR_STRLEN 14
 
-int rndis_filter_set_device_mac(struct net_device *ndev, char *mac)
+int rndis_filter_set_device_mac(struct netvsc_device *nvdev,
+                               const char *mac)
 {
-       struct netvsc_device *nvdev = net_device_to_netvsc_device(ndev);
        struct rndis_device *rdev = nvdev->extension;
        struct rndis_request *request;
        struct rndis_set_request *set;
@@ -654,11 +650,8 @@ int rndis_filter_set_device_mac(struct net_device *ndev, char *mac)
        wait_for_completion(&request->wait_event);
 
        set_complete = &request->response_msg.msg.set_complete;
-       if (set_complete->status != RNDIS_STATUS_SUCCESS) {
-               netdev_err(ndev, "Fail to set MAC on host side:0x%x\n",
-                          set_complete->status);
-               ret = -EINVAL;
-       }
+       if (set_complete->status != RNDIS_STATUS_SUCCESS)
+               ret = -EIO;
 
 cleanup:
        put_rndis_request(rdev, request);
@@ -791,27 +784,27 @@ cleanup:
        return ret;
 }
 
-static int rndis_filter_query_device_link_status(struct rndis_device *dev)
+static int rndis_filter_query_device_link_status(struct rndis_device *dev,
+                                                struct netvsc_device *net_device)
 {
        u32 size = sizeof(u32);
        u32 link_status;
-       int ret;
 
-       ret = rndis_filter_query_device(dev,
-                                     RNDIS_OID_GEN_MEDIA_CONNECT_STATUS,
-                                     &link_status, &size);
-
-       return ret;
+       return rndis_filter_query_device(dev, net_device,
+                                        RNDIS_OID_GEN_MEDIA_CONNECT_STATUS,
+                                        &link_status, &size);
 }
 
-static int rndis_filter_query_link_speed(struct rndis_device *dev)
+static int rndis_filter_query_link_speed(struct rndis_device *dev,
+                                        struct netvsc_device *net_device)
 {
        u32 size = sizeof(u32);
        u32 link_speed;
        struct net_device_context *ndc;
        int ret;
 
-       ret = rndis_filter_query_device(dev, RNDIS_OID_GEN_LINK_SPEED,
+       ret = rndis_filter_query_device(dev, net_device,
+                                       RNDIS_OID_GEN_LINK_SPEED,
                                        &link_speed, &size);
 
        if (!ret) {
@@ -880,14 +873,14 @@ void rndis_filter_update(struct netvsc_device *nvdev)
        schedule_work(&rdev->mcast_work);
 }
 
-static int rndis_filter_init_device(struct rndis_device *dev)
+static int rndis_filter_init_device(struct rndis_device *dev,
+                                   struct netvsc_device *nvdev)
 {
        struct rndis_request *request;
        struct rndis_initialize_request *init;
        struct rndis_initialize_complete *init_complete;
        u32 status;
        int ret;
-       struct netvsc_device *nvdev = net_device_to_netvsc_device(dev->ndev);
 
        request = get_rndis_request(dev, RNDIS_MSG_INIT,
                        RNDIS_MESSAGE_SIZE(struct rndis_initialize_request));
@@ -1024,12 +1017,17 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc)
 {
        struct net_device *ndev =
                hv_get_drvdata(new_sc->primary_channel->device_obj);
-       struct netvsc_device *nvscdev = net_device_to_netvsc_device(ndev);
+       struct net_device_context *ndev_ctx = netdev_priv(ndev);
+       struct netvsc_device *nvscdev;
        u16 chn_index = new_sc->offermsg.offer.sub_channel_index;
        struct netvsc_channel *nvchan;
        int ret;
 
-       if (chn_index >= nvscdev->num_chn)
+       /* This is safe because this callback only happens when
+        * new device is being setup and waiting on the channel_init_wait.
+        */
+       nvscdev = rcu_dereference_raw(ndev_ctx->nvdev);
+       if (!nvscdev || chn_index >= nvscdev->num_chn)
                return;
 
        nvchan = nvscdev->chan_table + chn_index;
@@ -1104,27 +1102,27 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
        rndis_device->ndev = net;
 
        /* Send the rndis initialization message */
-       ret = rndis_filter_init_device(rndis_device);
+       ret = rndis_filter_init_device(rndis_device, net_device);
        if (ret != 0)
                goto err_dev_remv;
 
        /* Get the MTU from the host */
        size = sizeof(u32);
-       ret = rndis_filter_query_device(rndis_device,
+       ret = rndis_filter_query_device(rndis_device, net_device,
                                        RNDIS_OID_GEN_MAXIMUM_FRAME_SIZE,
                                        &mtu, &size);
        if (ret == 0 && size == sizeof(u32) && mtu < net->mtu)
                net->mtu = mtu;
 
        /* Get the mac address */
-       ret = rndis_filter_query_device_mac(rndis_device);
+       ret = rndis_filter_query_device_mac(rndis_device, net_device);
        if (ret != 0)
                goto err_dev_remv;
 
        memcpy(device_info->mac_adr, rndis_device->hw_mac_adr, ETH_ALEN);
 
        /* Find HW offload capabilities */
-       ret = rndis_query_hwcaps(rndis_device, &hwcaps);
+       ret = rndis_query_hwcaps(rndis_device, net_device, &hwcaps);
        if (ret != 0)
                goto err_dev_remv;
 
@@ -1185,7 +1183,7 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
        if (ret)
                goto err_dev_remv;
 
-       rndis_filter_query_device_link_status(rndis_device);
+       rndis_filter_query_device_link_status(rndis_device, net_device);
 
        netdev_dbg(net, "Device MAC %pM link state %s\n",
                   rndis_device->hw_mac_adr,
@@ -1194,11 +1192,11 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
        if (net_device->nvsp_version < NVSP_PROTOCOL_VERSION_5)
                return net_device;
 
-       rndis_filter_query_link_speed(rndis_device);
+       rndis_filter_query_link_speed(rndis_device, net_device);
 
        /* vRSS setup */
        memset(&rsscap, 0, rsscap_size);
-       ret = rndis_filter_query_device(rndis_device,
+       ret = rndis_filter_query_device(rndis_device, net_device,
                                        OID_GEN_RECEIVE_SCALE_CAPABILITIES,
                                        &rsscap, &rsscap_size);
        if (ret || rsscap.num_recv_que < 2)