From d0922bf7981799fd86e248de330fb4152399d6c2 Mon Sep 17 00:00:00 2001 From: Haiyang Zhang Date: Mon, 29 Mar 2021 16:21:35 -0700 Subject: [PATCH] hv_netvsc: Add error handling while switching data path Add error handling in case of failure to send switching data path message to the host. Reported-by: Shachar Raindel Signed-off-by: Haiyang Zhang Signed-off-by: David S. Miller --- drivers/net/hyperv/hyperv_net.h | 6 +++++- drivers/net/hyperv/netvsc.c | 35 +++++++++++++++++++++++++++++++---- drivers/net/hyperv/netvsc_drv.c | 18 ++++++++++++------ 3 files changed, 48 insertions(+), 11 deletions(-) diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h index 59ac04a..442c520 100644 --- a/drivers/net/hyperv/hyperv_net.h +++ b/drivers/net/hyperv/hyperv_net.h @@ -269,7 +269,7 @@ int rndis_filter_receive(struct net_device *ndev, int rndis_filter_set_device_mac(struct netvsc_device *ndev, const char *mac); -void netvsc_switch_datapath(struct net_device *nv_dev, bool vf); +int netvsc_switch_datapath(struct net_device *nv_dev, bool vf); #define NVSP_INVALID_PROTOCOL_VERSION ((u32)0xFFFFFFFF) @@ -1718,4 +1718,8 @@ struct rndis_message { #define TRANSPORT_INFO_IPV6_TCP 0x10 #define TRANSPORT_INFO_IPV6_UDP 0x20 +#define RETRY_US_LO 5000 +#define RETRY_US_HI 10000 +#define RETRY_MAX 2000 /* >10 sec */ + #endif /* _HYPERV_NET_H */ diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index 5bce247..9d07c9c 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -31,12 +31,13 @@ * Switch the data path from the synthetic interface to the VF * interface. */ -void netvsc_switch_datapath(struct net_device *ndev, bool vf) +int netvsc_switch_datapath(struct net_device *ndev, bool vf) { struct net_device_context *net_device_ctx = netdev_priv(ndev); struct hv_device *dev = net_device_ctx->device_ctx; struct netvsc_device *nv_dev = rtnl_dereference(net_device_ctx->nvdev); struct nvsp_message *init_pkt = &nv_dev->channel_init_pkt; + int ret, retry = 0; /* Block sending traffic to VF if it's about to be gone */ if (!vf) @@ -51,15 +52,41 @@ void netvsc_switch_datapath(struct net_device *ndev, bool vf) init_pkt->msg.v4_msg.active_dp.active_datapath = NVSP_DATAPATH_SYNTHETIC; +again: trace_nvsp_send(ndev, init_pkt); - vmbus_sendpacket(dev->channel, init_pkt, + ret = vmbus_sendpacket(dev->channel, init_pkt, sizeof(struct nvsp_message), - (unsigned long)init_pkt, - VM_PKT_DATA_INBAND, + (unsigned long)init_pkt, VM_PKT_DATA_INBAND, VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + + /* If failed to switch to/from VF, let data_path_is_vf stay false, + * so we use synthetic path to send data. + */ + if (ret) { + if (ret != -EAGAIN) { + netdev_err(ndev, + "Unable to send sw datapath msg, err: %d\n", + ret); + return ret; + } + + if (retry++ < RETRY_MAX) { + usleep_range(RETRY_US_LO, RETRY_US_HI); + goto again; + } else { + netdev_err( + ndev, + "Retry failed to send sw datapath msg, err: %d\n", + ret); + return ret; + } + } + wait_for_completion(&nv_dev->channel_init_wait); net_device_ctx->data_path_is_vf = vf; + + return 0; } /* Worker to setup sub channels on initial setup diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index 97b5c9b..7349a70 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -38,9 +38,6 @@ #include "hyperv_net.h" #define RING_SIZE_MIN 64 -#define RETRY_US_LO 5000 -#define RETRY_US_HI 10000 -#define RETRY_MAX 2000 /* >10 sec */ #define LINKCHANGE_INT (2 * HZ) #define VF_TAKEOVER_INT (HZ / 10) @@ -2402,6 +2399,7 @@ static int netvsc_vf_changed(struct net_device *vf_netdev, unsigned long event) struct netvsc_device *netvsc_dev; struct net_device *ndev; bool vf_is_up = false; + int ret; if (event != NETDEV_GOING_DOWN) vf_is_up = netif_running(vf_netdev); @@ -2418,9 +2416,17 @@ static int netvsc_vf_changed(struct net_device *vf_netdev, unsigned long event) if (net_device_ctx->data_path_is_vf == vf_is_up) return NOTIFY_OK; - netvsc_switch_datapath(ndev, vf_is_up); - netdev_info(ndev, "Data path switched %s VF: %s\n", - vf_is_up ? "to" : "from", vf_netdev->name); + ret = netvsc_switch_datapath(ndev, vf_is_up); + + if (ret) { + netdev_err(ndev, + "Data path failed to switch %s VF: %s, err: %d\n", + vf_is_up ? "to" : "from", vf_netdev->name, ret); + return NOTIFY_DONE; + } else { + netdev_info(ndev, "Data path switched %s VF: %s\n", + vf_is_up ? "to" : "from", vf_netdev->name); + } return NOTIFY_OK; } -- 2.7.4