1 files changed, 90 insertions, 70 deletions

diff --git a/drivers/firewire/net.c b/drivers/firewire/net.c
index 18fdd9703b48..1a467a91fb0b 100644
--- a/drivers/firewire/net.c
+++ b/drivers/firewire/net.c
@@ -7,6 +7,7 @@
  */
 
 #include <linux/bug.h>
+#include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/firewire.h>
 #include <linux/firewire-constants.h>
@@ -26,8 +27,14 @@
 #include <asm/unaligned.h>
 #include <net/arp.h>
 
-#define FWNET_MAX_FRAGMENTS     25      /* arbitrary limit */
-#define FWNET_ISO_PAGE_COUNT    (PAGE_SIZE < 16 * 1024 ? 4 : 2)
+/* rx limits */
+#define FWNET_MAX_FRAGMENTS             30 /* arbitrary, > TX queue depth */
+#define FWNET_ISO_PAGE_COUNT            (PAGE_SIZE < 16*1024 ? 4 : 2)
+
+/* tx limits */
+#define FWNET_MAX_QUEUED_DATAGRAMS      20 /* < 64 = number of tlabels */
+#define FWNET_MIN_QUEUED_DATAGRAMS      10 /* should keep AT DMA busy enough */
+#define FWNET_TX_QUEUE_LEN              FWNET_MAX_QUEUED_DATAGRAMS /* ? */
 
 #define IEEE1394_BROADCAST_CHANNEL      31
 #define IEEE1394_ALL_NODES              (0xffc0 | 0x003f)
@@ -169,15 +176,8 @@ struct fwnet_device {
         struct fw_address_handler handler;
         u64 local_fifo;
 
-        /* List of packets to be sent */
-        struct list_head packet_list;
-        /*
-         * List of packets that were broadcasted.  When we get an ISO interrupt
-         * one of them has been sent
-         */
-        struct list_head broadcasted_list;
-        /* List of packets that have been sent but not yet acked */
-        struct list_head sent_list;
+        /* Number of tx datagrams that have been queued but not yet acked */
+        int queued_datagrams;
 
         struct list_head peer_list;
         struct fw_card *card;
@@ -195,7 +195,7 @@ struct fwnet_peer {
         unsigned pdg_size;        /* pd_list size */
 
         u16 datagram_label;       /* outgoing datagram label */
-        unsigned max_payload;     /* includes RFC2374_FRAG_HDR_SIZE overhead */
+        u16 max_payload;          /* includes RFC2374_FRAG_HDR_SIZE overhead */
         int node_id;
         int generation;
         unsigned speed;
@@ -203,22 +203,18 @@ struct fwnet_peer {
 
 /* This is our task struct. It's used for the packet complete callback.  */
 struct fwnet_packet_task {
-        /*
-         * ptask can actually be on dev->packet_list, dev->broadcasted_list,
-         * or dev->sent_list depending on its current state.
-         */
-        struct list_head pt_link;
         struct fw_transaction transaction;
         struct rfc2734_header hdr;
         struct sk_buff *skb;
         struct fwnet_device *dev;
 
         int outstanding_pkts;
-        unsigned max_payload;
         u64 fifo_addr;
         u16 dest_node;
+        u16 max_payload;
         u8 generation;
         u8 speed;
+        u8 enqueued;
 };
 
 /*
@@ -650,8 +646,6 @@ static int fwnet_finish_incoming_packet(struct net_device *net,
                 net->stats.rx_packets++;
                 net->stats.rx_bytes += skb->len;
         }
-        if (netif_queue_stopped(net))
-                netif_wake_queue(net);
 
         return 0;
 
@@ -660,8 +654,6 @@ static int fwnet_finish_incoming_packet(struct net_device *net,
         net->stats.rx_dropped++;
 
         dev_kfree_skb_any(skb);
-        if (netif_queue_stopped(net))
-                netif_wake_queue(net);
 
         return -ENOENT;
 }
@@ -793,15 +785,10 @@ static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
          * Datagram is not complete, we're done for the
          * moment.
          */
-        spin_unlock_irqrestore(&dev->lock, flags);
-
-        return 0;
+        retval = 0;
  fail:
         spin_unlock_irqrestore(&dev->lock, flags);
 
-        if (netif_queue_stopped(net))
-                netif_wake_queue(net);
-
         return retval;
 }
 
@@ -901,11 +888,19 @@ static void fwnet_free_ptask(struct fwnet_packet_task *ptask)
         kmem_cache_free(fwnet_packet_task_cache, ptask);
 }
 
+/* Caller must hold dev->lock. */
+static void dec_queued_datagrams(struct fwnet_device *dev)
+{
+        if (--dev->queued_datagrams == FWNET_MIN_QUEUED_DATAGRAMS)
+                netif_wake_queue(dev->netdev);
+}
+
 static int fwnet_send_packet(struct fwnet_packet_task *ptask);
 
 static void fwnet_transmit_packet_done(struct fwnet_packet_task *ptask)
 {
         struct fwnet_device *dev = ptask->dev;
+        struct sk_buff *skb = ptask->skb;
         unsigned long flags;
         bool free;
 
@@ -914,10 +909,14 @@ static void fwnet_transmit_packet_done(struct fwnet_packet_task *ptask)
         ptask->outstanding_pkts--;
 
         /* Check whether we or the networking TX soft-IRQ is last user. */
-        free = (ptask->outstanding_pkts == 0 && !list_empty(&ptask->pt_link));
+        free = (ptask->outstanding_pkts == 0 && ptask->enqueued);
+        if (free)
+                dec_queued_datagrams(dev);
 
-        if (ptask->outstanding_pkts == 0)
-                list_del(&ptask->pt_link);
+        if (ptask->outstanding_pkts == 0) {
+                dev->netdev->stats.tx_packets++;
+                dev->netdev->stats.tx_bytes += skb->len;
+        }
 
         spin_unlock_irqrestore(&dev->lock, flags);
 
@@ -926,7 +925,6 @@ static void fwnet_transmit_packet_done(struct fwnet_packet_task *ptask)
                 u16 fg_off;
                 u16 datagram_label;
                 u16 lf;
-                struct sk_buff *skb;
 
                 /* Update the ptask to point to the next fragment and send it */
                 lf = fwnet_get_hdr_lf(&ptask->hdr);
@@ -953,7 +951,7 @@ static void fwnet_transmit_packet_done(struct fwnet_packet_task *ptask)
                         datagram_label = fwnet_get_hdr_dgl(&ptask->hdr);
                         break;
                 }
-                skb = ptask->skb;
+
                 skb_pull(skb, ptask->max_payload);
                 if (ptask->outstanding_pkts > 1) {
                         fwnet_make_sf_hdr(&ptask->hdr, RFC2374_HDR_INTFRAG,
@@ -970,6 +968,31 @@ static void fwnet_transmit_packet_done(struct fwnet_packet_task *ptask)
                 fwnet_free_ptask(ptask);
 }
 
+static void fwnet_transmit_packet_failed(struct fwnet_packet_task *ptask)
+{
+        struct fwnet_device *dev = ptask->dev;
+        unsigned long flags;
+        bool free;
+
+        spin_lock_irqsave(&dev->lock, flags);
+
+        /* One fragment failed; don't try to send remaining fragments. */
+        ptask->outstanding_pkts = 0;
+
+        /* Check whether we or the networking TX soft-IRQ is last user. */
+        free = ptask->enqueued;
+        if (free)
+                dec_queued_datagrams(dev);
+
+        dev->netdev->stats.tx_dropped++;
+        dev->netdev->stats.tx_errors++;
+
+        spin_unlock_irqrestore(&dev->lock, flags);
+
+        if (free)
+                fwnet_free_ptask(ptask);
+}
+
 static void fwnet_write_complete(struct fw_card *card, int rcode,
                                  void *payload, size_t length, void *data)
 {
@@ -977,11 +1000,12 @@ static void fwnet_write_complete(struct fw_card *card, int rcode,
 
         ptask = data;
 
-        if (rcode == RCODE_COMPLETE)
+        if (rcode == RCODE_COMPLETE) {
                 fwnet_transmit_packet_done(ptask);
-        else
+        } else {
                 fw_error("fwnet_write_complete: failed: %x\n", rcode);
-                /* ??? error recovery */
+                fwnet_transmit_packet_failed(ptask);
+        }
 }
 
 static int fwnet_send_packet(struct fwnet_packet_task *ptask)
@@ -1039,9 +1063,11 @@ static int fwnet_send_packet(struct fwnet_packet_task *ptask)
                 spin_lock_irqsave(&dev->lock, flags);
 
                 /* If the AT tasklet already ran, we may be last user. */
-                free = (ptask->outstanding_pkts == 0 && list_empty(&ptask->pt_link));
+                free = (ptask->outstanding_pkts == 0 && !ptask->enqueued);
                 if (!free)
-                        list_add_tail(&ptask->pt_link, &dev->broadcasted_list);
+                        ptask->enqueued = true;
+                else
+                        dec_queued_datagrams(dev);
 
                 spin_unlock_irqrestore(&dev->lock, flags);
 
@@ -1056,9 +1082,11 @@ static int fwnet_send_packet(struct fwnet_packet_task *ptask)
         spin_lock_irqsave(&dev->lock, flags);
 
         /* If the AT tasklet already ran, we may be last user. */
-        free = (ptask->outstanding_pkts == 0 && list_empty(&ptask->pt_link));
+        free = (ptask->outstanding_pkts == 0 && !ptask->enqueued);
         if (!free)
-                list_add_tail(&ptask->pt_link, &dev->sent_list);
+                ptask->enqueued = true;
+        else
+                dec_queued_datagrams(dev);
 
         spin_unlock_irqrestore(&dev->lock, flags);
 
@@ -1224,6 +1252,15 @@ static netdev_tx_t fwnet_tx(struct sk_buff *skb, struct net_device *net)
         struct fwnet_peer *peer;
         unsigned long flags;
 
+        spin_lock_irqsave(&dev->lock, flags);
+
+        /* Can this happen? */
+        if (netif_queue_stopped(dev->netdev)) {
+                spin_unlock_irqrestore(&dev->lock, flags);
+
+                return NETDEV_TX_BUSY;
+        }
+
         ptask = kmem_cache_alloc(fwnet_packet_task_cache, GFP_ATOMIC);
         if (ptask == NULL)
                 goto fail;
@@ -1242,9 +1279,6 @@ static netdev_tx_t fwnet_tx(struct sk_buff *skb, struct net_device *net)
         proto = hdr_buf.h_proto;
         dg_size = skb->len;
 
-        /* serialize access to peer, including peer->datagram_label */
-        spin_lock_irqsave(&dev->lock, flags);
-
         /*
          * Set the transmission type for the packet.  ARP packets and IP
          * broadcast packets are sent via GASP.
@@ -1266,7 +1300,7 @@ static netdev_tx_t fwnet_tx(struct sk_buff *skb, struct net_device *net)
 
                 peer = fwnet_peer_find_by_guid(dev, be64_to_cpu(guid));
                 if (!peer || peer->fifo == FWNET_NO_FIFO_ADDR)
-                        goto fail_unlock;
+                        goto fail;
 
                 generation         = peer->generation;
                 dest_node          = peer->node_id;
@@ -1320,18 +1354,21 @@ static netdev_tx_t fwnet_tx(struct sk_buff *skb, struct net_device *net)
                 max_payload += RFC2374_FRAG_HDR_SIZE;
         }
 
+        if (++dev->queued_datagrams == FWNET_MAX_QUEUED_DATAGRAMS)
+                netif_stop_queue(dev->netdev);
+
         spin_unlock_irqrestore(&dev->lock, flags);
 
         ptask->max_payload = max_payload;
-        INIT_LIST_HEAD(&ptask->pt_link);
+        ptask->enqueued    = 0;
 
         fwnet_send_packet(ptask);
 
         return NETDEV_TX_OK;
 
- fail_unlock:
-        spin_unlock_irqrestore(&dev->lock, flags);
  fail:
+        spin_unlock_irqrestore(&dev->lock, flags);
+
         if (ptask)
                 kmem_cache_free(fwnet_packet_task_cache, ptask);
 
@@ -1377,7 +1414,7 @@ static void fwnet_init_dev(struct net_device *net)
         net->addr_len           = FWNET_ALEN;
         net->hard_header_len    = FWNET_HLEN;
         net->type               = ARPHRD_IEEE1394;
-        net->tx_queue_len       = 10;
+        net->tx_queue_len       = FWNET_TX_QUEUE_LEN;
 }
 
 /* caller must hold fwnet_device_mutex */
@@ -1457,14 +1494,9 @@ static int fwnet_probe(struct device *_dev)
         dev->broadcast_rcv_context = NULL;
         dev->broadcast_xmt_max_payload = 0;
         dev->broadcast_xmt_datagramlabel = 0;
-
         dev->local_fifo = FWNET_NO_FIFO_ADDR;
-
-        INIT_LIST_HEAD(&dev->packet_list);
-        INIT_LIST_HEAD(&dev->broadcasted_list);
-        INIT_LIST_HEAD(&dev->sent_list);
+        dev->queued_datagrams = 0;
         INIT_LIST_HEAD(&dev->peer_list);
-
         dev->card = card;
         dev->netdev = net;
 
@@ -1522,7 +1554,7 @@ static int fwnet_remove(struct device *_dev)
         struct fwnet_peer *peer = dev_get_drvdata(_dev);
         struct fwnet_device *dev = peer->dev;
         struct net_device *net;
-        struct fwnet_packet_task *ptask, *pt_next;
+        int i;
 
         mutex_lock(&fwnet_device_mutex);
 
@@ -1540,21 +1572,9 @@ static int fwnet_remove(struct device *_dev)
                                               dev->card);
                         fw_iso_context_destroy(dev->broadcast_rcv_context);
                 }
-                list_for_each_entry_safe(ptask, pt_next,
-                                         &dev->packet_list, pt_link) {
-                        dev_kfree_skb_any(ptask->skb);
-                        kmem_cache_free(fwnet_packet_task_cache, ptask);
-                }
-                list_for_each_entry_safe(ptask, pt_next,
-                                         &dev->broadcasted_list, pt_link) {
-                        dev_kfree_skb_any(ptask->skb);
-                        kmem_cache_free(fwnet_packet_task_cache, ptask);
-                }
-                list_for_each_entry_safe(ptask, pt_next,
-                                         &dev->sent_list, pt_link) {
-                        dev_kfree_skb_any(ptask->skb);
-                        kmem_cache_free(fwnet_packet_task_cache, ptask);
-                }
+                for (i = 0; dev->queued_datagrams && i < 5; i++)
+                        ssleep(1);
+                WARN_ON(dev->queued_datagrams);
                 list_del(&dev->dev_link);
 
                 free_netdev(net);