arcnet: add err_skb package for package status feedback
authorMichael Grzeschik <m.grzeschik@pengutronix.de>
Wed, 28 Jun 2017 16:32:18 +0000 (18:32 +0200)
committerDavid S. Miller <davem@davemloft.net>
Thu, 29 Jun 2017 19:26:13 +0000 (15:26 -0400)
We need to track the status of our queued packages. This way the driving
process knows if failed packages need to be retransmitted. For this
purpose we queue the transferred/failed packages back into the err_skb
message queue added with some status information.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/arcnet/arcdevice.h
drivers/net/arcnet/arcnet.c

index 20bfb9ba83ea23d38880676198e279513ed70123..cbb4f8566bbe58a72eae8bbec0633b83687c5e13 100644 (file)
@@ -269,6 +269,10 @@ struct arcnet_local {
 
        struct timer_list       timer;
 
+       struct net_device *dev;
+       int reply_status;
+       struct tasklet_struct reply_tasklet;
+
        /*
         * Buffer management: an ARCnet card has 4 x 512-byte buffers, each of
         * which can be used for either sending or receiving.  The new dynamic
index 62ee439d58829574d732e84b8afba738871a43e5..d87f4da29f1138f6ee24b7dcc7bd6e775d9d8d0b 100644 (file)
@@ -51,6 +51,7 @@
 #include <net/arp.h>
 #include <linux/init.h>
 #include <linux/jiffies.h>
+#include <linux/errqueue.h>
 
 #include <linux/leds.h>
 
@@ -391,6 +392,52 @@ static void arcnet_timer(unsigned long data)
        }
 }
 
+static void arcnet_reply_tasklet(unsigned long data)
+{
+       struct arcnet_local *lp = (struct arcnet_local *)data;
+
+       struct sk_buff *ackskb, *skb;
+       struct sock_exterr_skb *serr;
+       struct sock *sk;
+       int ret;
+
+       local_irq_disable();
+       skb = lp->outgoing.skb;
+       if (!skb || !skb->sk) {
+               local_irq_enable();
+               return;
+       }
+
+       sock_hold(skb->sk);
+       sk = skb->sk;
+       ackskb = skb_clone_sk(skb);
+       sock_put(skb->sk);
+
+       if (!ackskb) {
+               local_irq_enable();
+               return;
+       }
+
+       serr = SKB_EXT_ERR(ackskb);
+       memset(serr, 0, sizeof(*serr));
+       serr->ee.ee_errno = ENOMSG;
+       serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;
+       serr->ee.ee_data = skb_shinfo(skb)->tskey;
+       serr->ee.ee_info = lp->reply_status;
+
+       /* finally erasing outgoing skb */
+       dev_kfree_skb(lp->outgoing.skb);
+       lp->outgoing.skb = NULL;
+
+       ackskb->dev = lp->dev;
+
+       ret = sock_queue_err_skb(sk, ackskb);
+       if (ret)
+               kfree_skb(ackskb);
+
+       local_irq_enable();
+};
+
 struct net_device *alloc_arcdev(const char *name)
 {
        struct net_device *dev;
@@ -401,6 +448,7 @@ struct net_device *alloc_arcdev(const char *name)
        if (dev) {
                struct arcnet_local *lp = netdev_priv(dev);
 
+               lp->dev = dev;
                spin_lock_init(&lp->lock);
                init_timer(&lp->timer);
                lp->timer.data = (unsigned long) dev;
@@ -436,6 +484,9 @@ int arcnet_open(struct net_device *dev)
                arc_cont(D_PROTO, "\n");
        }
 
+       tasklet_init(&lp->reply_tasklet, arcnet_reply_tasklet,
+                    (unsigned long)lp);
+
        arc_printk(D_INIT, dev, "arcnet_open: resetting card.\n");
 
        /* try to put the card in a defined state - if it fails the first
@@ -527,6 +578,8 @@ int arcnet_close(struct net_device *dev)
        netif_stop_queue(dev);
        netif_carrier_off(dev);
 
+       tasklet_kill(&lp->reply_tasklet);
+
        /* flush TX and disable RX */
        lp->hw.intmask(dev, 0);
        lp->hw.command(dev, NOTXcmd);   /* stop transmit */
@@ -635,13 +688,13 @@ netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
                txbuf = -1;
 
        if (txbuf != -1) {
+               lp->outgoing.skb = skb;
                if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
                    !proto->ack_tx) {
                        /* done right away and we don't want to acknowledge
                         *  the package later - forget about it now
                         */
                        dev->stats.tx_bytes += skb->len;
-                       dev_kfree_skb(skb);
                } else {
                        /* do it the 'split' way */
                        lp->outgoing.proto = proto;
@@ -842,8 +895,16 @@ irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 
                /* a transmit finished, and we're interested in it. */
                if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
+                       int ackstatus;
                        lp->intmask &= ~(TXFREEflag | EXCNAKflag);
 
+                       if (status & TXACKflag)
+                               ackstatus = 2;
+                       else if (lp->excnak_pending)
+                               ackstatus = 1;
+                       else
+                               ackstatus = 0;
+
                        arc_printk(D_DURING, dev, "TX IRQ (stat=%Xh)\n",
                                   status);
 
@@ -866,18 +927,11 @@ irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 
                                if (lp->outgoing.proto &&
                                    lp->outgoing.proto->ack_tx) {
-                                       int ackstatus;
-
-                                       if (status & TXACKflag)
-                                               ackstatus = 2;
-                                       else if (lp->excnak_pending)
-                                               ackstatus = 1;
-                                       else
-                                               ackstatus = 0;
-
                                        lp->outgoing.proto
                                                ->ack_tx(dev, ackstatus);
                                }
+                               lp->reply_status = ackstatus;
+                               tasklet_hi_schedule(&lp->reply_tasklet);
                        }
                        if (lp->cur_tx != -1)
                                release_arcbuf(dev, lp->cur_tx);