From: Alex Ng Date: Wed, 20 Sep 2017 18:17:35 +0000 (-0700) Subject: hv_netvsc: fix send buffer failure on MTU change X-Git-Tag: v4.14-rc2~10^2~10 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=0ab09befdbb7ca9b969d6206108629ddff43876e;p=platform%2Fkernel%2Flinux-rpi3.git hv_netvsc: fix send buffer failure on MTU change If MTU is changed the host would reject the send buffer change. This problem is result of recent change to allow changing send buffer size. Every time we change the MTU, we store the previous net_device section count before destroying the buffer, but we don’t store the previous section size. When we reinitialize the buffer, its size is calculated by multiplying the previous count and previous size. Since we continuously increase the MTU, the host returns us a decreasing count value while the section size is reinitialized to 1728 bytes every time. This eventually leads to a condition where the calculated buf_size is so small that the host rejects it. Fixes: 8b5327975ae1 ("netvsc: allow controlling send/recv buffer size") Signed-off-by: Alex Ng Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h index d98cdfb..5176be7 100644 --- a/drivers/net/hyperv/hyperv_net.h +++ b/drivers/net/hyperv/hyperv_net.h @@ -150,6 +150,8 @@ struct netvsc_device_info { u32 num_chn; u32 send_sections; u32 recv_sections; + u32 send_section_size; + u32 recv_section_size; }; enum rndis_device_state { diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index a5511b7..8d5077f 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -76,9 +76,6 @@ static struct netvsc_device *alloc_net_device(void) net_device->max_pkt = RNDIS_MAX_PKT_DEFAULT; net_device->pkt_align = RNDIS_PKT_ALIGN_DEFAULT; - net_device->recv_section_size = NETVSC_RECV_SECTION_SIZE; - net_device->send_section_size = NETVSC_SEND_SECTION_SIZE; - init_completion(&net_device->channel_init_wait); init_waitqueue_head(&net_device->subchan_open); INIT_WORK(&net_device->subchan_work, rndis_set_subchannel); @@ -262,7 +259,7 @@ static int netvsc_init_buf(struct hv_device *device, int ret = 0; /* Get receive buffer area. */ - buf_size = device_info->recv_sections * net_device->recv_section_size; + buf_size = device_info->recv_sections * device_info->recv_section_size; buf_size = roundup(buf_size, PAGE_SIZE); net_device->recv_buf = vzalloc(buf_size); @@ -344,7 +341,7 @@ static int netvsc_init_buf(struct hv_device *device, goto cleanup; /* Now setup the send buffer. */ - buf_size = device_info->send_sections * net_device->send_section_size; + buf_size = device_info->send_sections * device_info->send_section_size; buf_size = round_up(buf_size, PAGE_SIZE); net_device->send_buf = vzalloc(buf_size); diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index d4902ee5f..a32ae02 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -848,7 +848,9 @@ static int netvsc_set_channels(struct net_device *net, device_info.num_chn = count; device_info.ring_size = ring_size; device_info.send_sections = nvdev->send_section_cnt; + device_info.send_section_size = nvdev->send_section_size; device_info.recv_sections = nvdev->recv_section_cnt; + device_info.recv_section_size = nvdev->recv_section_size; rndis_filter_device_remove(dev, nvdev); @@ -963,7 +965,9 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu) device_info.ring_size = ring_size; device_info.num_chn = nvdev->num_chn; device_info.send_sections = nvdev->send_section_cnt; + device_info.send_section_size = nvdev->send_section_size; device_info.recv_sections = nvdev->recv_section_cnt; + device_info.recv_section_size = nvdev->recv_section_size; rndis_filter_device_remove(hdev, nvdev); @@ -1485,7 +1489,9 @@ static int netvsc_set_ringparam(struct net_device *ndev, device_info.num_chn = nvdev->num_chn; device_info.ring_size = ring_size; device_info.send_sections = new_tx; + device_info.send_section_size = nvdev->send_section_size; device_info.recv_sections = new_rx; + device_info.recv_section_size = nvdev->recv_section_size; netif_device_detach(ndev); was_opened = rndis_filter_opened(nvdev); @@ -1934,7 +1940,9 @@ static int netvsc_probe(struct hv_device *dev, device_info.ring_size = ring_size; device_info.num_chn = VRSS_CHANNEL_DEFAULT; device_info.send_sections = NETVSC_DEFAULT_TX; + device_info.send_section_size = NETVSC_SEND_SECTION_SIZE; device_info.recv_sections = NETVSC_DEFAULT_RX; + device_info.recv_section_size = NETVSC_RECV_SECTION_SIZE; nvdev = rndis_filter_device_add(dev, &device_info); if (IS_ERR(nvdev)) {