From 61356088ace1866a847a727d4d40da7bf00b67fc Mon Sep 17 00:00:00 2001 From: Reinhard Speyerer Date: Wed, 12 Jun 2019 19:02:13 +0200 Subject: [PATCH 1/4] qmi_wwan: add support for QMAP padding in the RX path The QMAP code in the qmi_wwan driver is based on the CodeAurora GobiNet driver which does not process QMAP padding in the RX path correctly. Add support for QMAP padding to qmimux_rx_fixup() according to the description of the rmnet driver. Fixes: c6adf77953bc ("net: usb: qmi_wwan: add qmap mux protocol support") Cc: Daniele Palmas Signed-off-by: Reinhard Speyerer Signed-off-by: David S. Miller --- drivers/net/usb/qmi_wwan.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c index d9a6699abe59..fd3d078a1923 100644 --- a/drivers/net/usb/qmi_wwan.c +++ b/drivers/net/usb/qmi_wwan.c @@ -153,7 +153,7 @@ static bool qmimux_has_slaves(struct usbnet *dev) static int qmimux_rx_fixup(struct usbnet *dev, struct sk_buff *skb) { - unsigned int len, offset = 0; + unsigned int len, offset = 0, pad_len, pkt_len; struct qmimux_hdr *hdr; struct net_device *net; struct sk_buff *skbn; @@ -171,10 +171,16 @@ static int qmimux_rx_fixup(struct usbnet *dev, struct sk_buff *skb) if (hdr->pad & 0x80) goto skip; + /* extract padding length and check for valid length info */ + pad_len = hdr->pad & 0x3f; + if (len == 0 || pad_len >= len) + goto skip; + pkt_len = len - pad_len; + net = qmimux_find_dev(dev, hdr->mux_id); if (!net) goto skip; - skbn = netdev_alloc_skb(net, len); + skbn = netdev_alloc_skb(net, pkt_len); if (!skbn) return 0; skbn->dev = net; @@ -191,7 +197,7 @@ static int qmimux_rx_fixup(struct usbnet *dev, struct sk_buff *skb) goto skip; } - skb_put_data(skbn, skb->data + offset + qmimux_hdr_sz, len); + skb_put_data(skbn, skb->data + offset + qmimux_hdr_sz, pkt_len); if (netif_rx(skbn) != NET_RX_SUCCESS) return 0; From 44f82312fe9113bab6642f4d0eab6b1b7902b6e1 Mon Sep 17 00:00:00 2001 From: Reinhard Speyerer Date: Wed, 12 Jun 2019 19:02:46 +0200 Subject: [PATCH 2/4] qmi_wwan: add network device usage statistics for qmimux devices Add proper network device usage statistics for qmimux devices instead of reporting all-zero values for them. Fixes: c6adf77953bc ("net: usb: qmi_wwan: add qmap mux protocol support") Cc: Daniele Palmas Signed-off-by: Reinhard Speyerer Signed-off-by: David S. Miller --- drivers/net/usb/qmi_wwan.c | 76 +++++++++++++++++++++++++++++++++++--- 1 file changed, 71 insertions(+), 5 deletions(-) diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c index fd3d078a1923..b0a96459621f 100644 --- a/drivers/net/usb/qmi_wwan.c +++ b/drivers/net/usb/qmi_wwan.c @@ -22,6 +22,7 @@ #include #include #include +#include /* This driver supports wwan (3G/LTE/?) devices using a vendor * specific management protocol called Qualcomm MSM Interface (QMI) - @@ -75,6 +76,7 @@ struct qmimux_hdr { struct qmimux_priv { struct net_device *real_dev; u8 mux_id; + struct pcpu_sw_netstats __percpu *stats64; }; static int qmimux_open(struct net_device *dev) @@ -101,19 +103,65 @@ static netdev_tx_t qmimux_start_xmit(struct sk_buff *skb, struct net_device *dev struct qmimux_priv *priv = netdev_priv(dev); unsigned int len = skb->len; struct qmimux_hdr *hdr; + netdev_tx_t ret; hdr = skb_push(skb, sizeof(struct qmimux_hdr)); hdr->pad = 0; hdr->mux_id = priv->mux_id; hdr->pkt_len = cpu_to_be16(len); skb->dev = priv->real_dev; - return dev_queue_xmit(skb); + ret = dev_queue_xmit(skb); + + if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) { + struct pcpu_sw_netstats *stats64 = this_cpu_ptr(priv->stats64); + + u64_stats_update_begin(&stats64->syncp); + stats64->tx_packets++; + stats64->tx_bytes += len; + u64_stats_update_end(&stats64->syncp); + } else { + dev->stats.tx_dropped++; + } + + return ret; +} + +static void qmimux_get_stats64(struct net_device *net, + struct rtnl_link_stats64 *stats) +{ + struct qmimux_priv *priv = netdev_priv(net); + unsigned int start; + int cpu; + + netdev_stats_to_stats64(stats, &net->stats); + + for_each_possible_cpu(cpu) { + struct pcpu_sw_netstats *stats64; + u64 rx_packets, rx_bytes; + u64 tx_packets, tx_bytes; + + stats64 = per_cpu_ptr(priv->stats64, cpu); + + do { + start = u64_stats_fetch_begin_irq(&stats64->syncp); + rx_packets = stats64->rx_packets; + rx_bytes = stats64->rx_bytes; + tx_packets = stats64->tx_packets; + tx_bytes = stats64->tx_bytes; + } while (u64_stats_fetch_retry_irq(&stats64->syncp, start)); + + stats->rx_packets += rx_packets; + stats->rx_bytes += rx_bytes; + stats->tx_packets += tx_packets; + stats->tx_bytes += tx_bytes; + } } static const struct net_device_ops qmimux_netdev_ops = { - .ndo_open = qmimux_open, - .ndo_stop = qmimux_stop, - .ndo_start_xmit = qmimux_start_xmit, + .ndo_open = qmimux_open, + .ndo_stop = qmimux_stop, + .ndo_start_xmit = qmimux_start_xmit, + .ndo_get_stats64 = qmimux_get_stats64, }; static void qmimux_setup(struct net_device *dev) @@ -198,8 +246,19 @@ static int qmimux_rx_fixup(struct usbnet *dev, struct sk_buff *skb) } skb_put_data(skbn, skb->data + offset + qmimux_hdr_sz, pkt_len); - if (netif_rx(skbn) != NET_RX_SUCCESS) + if (netif_rx(skbn) != NET_RX_SUCCESS) { + net->stats.rx_errors++; return 0; + } else { + struct pcpu_sw_netstats *stats64; + struct qmimux_priv *priv = netdev_priv(net); + + stats64 = this_cpu_ptr(priv->stats64); + u64_stats_update_begin(&stats64->syncp); + stats64->rx_packets++; + stats64->rx_bytes += pkt_len; + u64_stats_update_end(&stats64->syncp); + } skip: offset += len + qmimux_hdr_sz; @@ -223,6 +282,12 @@ static int qmimux_register_device(struct net_device *real_dev, u8 mux_id) priv->mux_id = mux_id; priv->real_dev = real_dev; + priv->stats64 = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); + if (!priv->stats64) { + err = -ENOBUFS; + goto out_free_newdev; + } + err = register_netdevice(new_dev); if (err < 0) goto out_free_newdev; @@ -252,6 +317,7 @@ static void qmimux_unregister_device(struct net_device *dev) struct qmimux_priv *priv = netdev_priv(dev); struct net_device *real_dev = priv->real_dev; + free_percpu(priv->stats64); netdev_upper_dev_unlink(real_dev, dev); unregister_netdevice(dev); From a8fdde1cb830e560208af42b6c10750137f53eb3 Mon Sep 17 00:00:00 2001 From: Reinhard Speyerer Date: Wed, 12 Jun 2019 19:03:15 +0200 Subject: [PATCH 3/4] qmi_wwan: avoid RCU stalls on device disconnect when in QMAP mode Switch qmimux_unregister_device() and qmi_wwan_disconnect() to use unregister_netdevice_queue() and unregister_netdevice_many() instead of unregister_netdevice(). This avoids RCU stalls which have been observed on device disconnect in certain setups otherwise. Fixes: c6adf77953bc ("net: usb: qmi_wwan: add qmap mux protocol support") Cc: Daniele Palmas Signed-off-by: Reinhard Speyerer Signed-off-by: David S. Miller --- drivers/net/usb/qmi_wwan.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c index b0a96459621f..c6fbc2a2a785 100644 --- a/drivers/net/usb/qmi_wwan.c +++ b/drivers/net/usb/qmi_wwan.c @@ -312,14 +312,15 @@ static int qmimux_register_device(struct net_device *real_dev, u8 mux_id) return err; } -static void qmimux_unregister_device(struct net_device *dev) +static void qmimux_unregister_device(struct net_device *dev, + struct list_head *head) { struct qmimux_priv *priv = netdev_priv(dev); struct net_device *real_dev = priv->real_dev; free_percpu(priv->stats64); netdev_upper_dev_unlink(real_dev, dev); - unregister_netdevice(dev); + unregister_netdevice_queue(dev, head); /* Get rid of the reference to real_dev */ dev_put(real_dev); @@ -490,7 +491,7 @@ static ssize_t del_mux_store(struct device *d, struct device_attribute *attr, c ret = -EINVAL; goto err; } - qmimux_unregister_device(del_dev); + qmimux_unregister_device(del_dev, NULL); if (!qmimux_has_slaves(dev)) info->flags &= ~QMI_WWAN_FLAG_MUX; @@ -1500,6 +1501,7 @@ static void qmi_wwan_disconnect(struct usb_interface *intf) struct qmi_wwan_state *info; struct list_head *iter; struct net_device *ldev; + LIST_HEAD(list); /* called twice if separate control and data intf */ if (!dev) @@ -1512,8 +1514,9 @@ static void qmi_wwan_disconnect(struct usb_interface *intf) } rcu_read_lock(); netdev_for_each_upper_dev_rcu(dev->net, ldev, iter) - qmimux_unregister_device(ldev); + qmimux_unregister_device(ldev, &list); rcu_read_unlock(); + unregister_netdevice_many(&list); rtnl_unlock(); info->flags &= ~QMI_WWAN_FLAG_MUX; } From 36815b416fa48766ac5a98e4b2dc3ebc5887222e Mon Sep 17 00:00:00 2001 From: Reinhard Speyerer Date: Wed, 12 Jun 2019 19:03:50 +0200 Subject: [PATCH 4/4] qmi_wwan: extend permitted QMAP mux_id value range Permit mux_id values up to 254 to be used in qmimux_register_device() for compatibility with ip(8) and the rmnet driver. Fixes: c6adf77953bc ("net: usb: qmi_wwan: add qmap mux protocol support") Cc: Daniele Palmas Signed-off-by: Reinhard Speyerer Signed-off-by: David S. Miller --- Documentation/ABI/testing/sysfs-class-net-qmi | 4 ++-- drivers/net/usb/qmi_wwan.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-class-net-qmi b/Documentation/ABI/testing/sysfs-class-net-qmi index 7122d6264c49..c310db4ccbc2 100644 --- a/Documentation/ABI/testing/sysfs-class-net-qmi +++ b/Documentation/ABI/testing/sysfs-class-net-qmi @@ -29,7 +29,7 @@ Contact: Bjørn Mork Description: Unsigned integer. - Write a number ranging from 1 to 127 to add a qmap mux + Write a number ranging from 1 to 254 to add a qmap mux based network device, supported by recent Qualcomm based modems. @@ -46,5 +46,5 @@ Contact: Bjørn Mork Description: Unsigned integer. - Write a number ranging from 1 to 127 to delete a previously + Write a number ranging from 1 to 254 to delete a previously created qmap mux based network device. diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c index c6fbc2a2a785..780c10ee359b 100644 --- a/drivers/net/usb/qmi_wwan.c +++ b/drivers/net/usb/qmi_wwan.c @@ -429,8 +429,8 @@ static ssize_t add_mux_store(struct device *d, struct device_attribute *attr, c if (kstrtou8(buf, 0, &mux_id)) return -EINVAL; - /* mux_id [1 - 0x7f] range empirically found */ - if (mux_id < 1 || mux_id > 0x7f) + /* mux_id [1 - 254] for compatibility with ip(8) and the rmnet driver */ + if (mux_id < 1 || mux_id > 254) return -EINVAL; if (!rtnl_trylock())