ibmveth: Remove dead frag processing code
Brian King [Fri, 17 Aug 2007 14:16:49 +0000 (09:16 -0500)]
Removes dead frag processing code from ibmveth. Since NETIF_F_SG was
not set, this code was never executed. Also, since the ibmveth
interface can only handle 6 fragments, core networking code would need
to be modified in order to efficiently enable this support.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/net/ibmveth.c
drivers/net/ibmveth.h

index 40cb00e..f6be7b2 100644 (file)
@@ -28,7 +28,6 @@
 /**************************************************************************/
 /*
   TODO:
-  - remove frag processing code - no longer needed
   - add support for sysfs
   - possibly remove procfs support
 */
@@ -128,9 +127,6 @@ struct ibmveth_stat ibmveth_stats[] = {
        { "replenish_add_buff_success", IBMVETH_STAT_OFF(replenish_add_buff_success) },
        { "rx_invalid_buffer", IBMVETH_STAT_OFF(rx_invalid_buffer) },
        { "rx_no_buffer", IBMVETH_STAT_OFF(rx_no_buffer) },
-       { "tx_multidesc_send", IBMVETH_STAT_OFF(tx_multidesc_send) },
-       { "tx_linearized", IBMVETH_STAT_OFF(tx_linearized) },
-       { "tx_linearize_failed", IBMVETH_STAT_OFF(tx_linearize_failed) },
        { "tx_map_failed", IBMVETH_STAT_OFF(tx_map_failed) },
        { "tx_send_failed", IBMVETH_STAT_OFF(tx_send_failed) },
 };
@@ -843,9 +839,8 @@ static int ibmveth_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 static int ibmveth_start_xmit(struct sk_buff *skb, struct net_device *netdev)
 {
        struct ibmveth_adapter *adapter = netdev->priv;
-       union ibmveth_buf_desc desc[IbmVethMaxSendFrags];
+       union ibmveth_buf_desc desc;
        unsigned long lpar_rc;
-       int nfrags = 0, curfrag;
        unsigned long correlator;
        unsigned long flags;
        unsigned int retry_count;
@@ -855,25 +850,11 @@ static int ibmveth_start_xmit(struct sk_buff *skb, struct net_device *netdev)
        unsigned int tx_send_failed = 0;
        unsigned int tx_map_failed = 0;
 
-
-       if ((skb_shinfo(skb)->nr_frags + 1) > IbmVethMaxSendFrags) {
-               tx_dropped++;
-               goto out;
-       }
-
-       memset(&desc, 0, sizeof(desc));
-
-       /* nfrags = number of frags after the initial fragment */
-       nfrags = skb_shinfo(skb)->nr_frags;
-
-       if(nfrags)
-               adapter->tx_multidesc_send++;
-
-       /* map the initial fragment */
-       desc[0].fields.length  = nfrags ? skb->len - skb->data_len : skb->len;
-       desc[0].fields.address = dma_map_single(&adapter->vdev->dev, skb->data,
-                                       desc[0].fields.length, DMA_TO_DEVICE);
-       desc[0].fields.valid   = 1;
+       desc.desc = 0;
+       desc.fields.length  = skb->len;
+       desc.fields.address = dma_map_single(&adapter->vdev->dev, skb->data,
+                                            desc.fields.length, DMA_TO_DEVICE);
+       desc.fields.valid   = 1;
 
        if (skb->ip_summed == CHECKSUM_PARTIAL &&
            ip_hdr(skb)->protocol != IPPROTO_TCP && skb_checksum_help(skb)) {
@@ -885,75 +866,34 @@ static int ibmveth_start_xmit(struct sk_buff *skb, struct net_device *netdev)
        if (skb->ip_summed == CHECKSUM_PARTIAL) {
                unsigned char *buf = skb_transport_header(skb) + skb->csum_offset;
 
-               desc[0].fields.no_csum = 1;
-               desc[0].fields.csum_good = 1;
+               desc.fields.no_csum = 1;
+               desc.fields.csum_good = 1;
 
                /* Need to zero out the checksum */
                buf[0] = 0;
                buf[1] = 0;
        }
 
-       if(dma_mapping_error(desc[0].fields.address)) {
-               ibmveth_error_printk("tx: unable to map initial fragment\n");
+       if (dma_mapping_error(desc.fields.address)) {
+               ibmveth_error_printk("tx: unable to map xmit buffer\n");
                tx_map_failed++;
                tx_dropped++;
                goto out;
        }
 
-       curfrag = nfrags;
-
-       /* map fragments past the initial portion if there are any */
-       while(curfrag--) {
-               skb_frag_t *frag = &skb_shinfo(skb)->frags[curfrag];
-               desc[curfrag+1].fields.address
-                       = dma_map_single(&adapter->vdev->dev,
-                               page_address(frag->page) + frag->page_offset,
-                               frag->size, DMA_TO_DEVICE);
-               desc[curfrag+1].fields.length = frag->size;
-               desc[curfrag+1].fields.valid  = 1;
-               if (skb->ip_summed == CHECKSUM_PARTIAL) {
-                       desc[curfrag+1].fields.no_csum = 1;
-                       desc[curfrag+1].fields.csum_good = 1;
-               }
-
-               if(dma_mapping_error(desc[curfrag+1].fields.address)) {
-                       ibmveth_error_printk("tx: unable to map fragment %d\n", curfrag);
-                       tx_map_failed++;
-                       tx_dropped++;
-                       /* Free all the mappings we just created */
-                       while(curfrag < nfrags) {
-                               dma_unmap_single(&adapter->vdev->dev,
-                                                desc[curfrag+1].fields.address,
-                                                desc[curfrag+1].fields.length,
-                                                DMA_TO_DEVICE);
-                               curfrag++;
-                       }
-                       goto out;
-               }
-       }
-
        /* send the frame. Arbitrarily set retrycount to 1024 */
        correlator = 0;
        retry_count = 1024;
        do {
                lpar_rc = h_send_logical_lan(adapter->vdev->unit_address,
-                                            desc[0].desc,
-                                            desc[1].desc,
-                                            desc[2].desc,
-                                            desc[3].desc,
-                                            desc[4].desc,
-                                            desc[5].desc,
-                                            correlator,
-                                            &correlator);
+                                            desc.desc, 0, 0, 0, 0, 0,
+                                            correlator, &correlator);
        } while ((lpar_rc == H_BUSY) && (retry_count--));
 
        if(lpar_rc != H_SUCCESS && lpar_rc != H_DROPPED) {
-               int i;
                ibmveth_error_printk("tx: h_send_logical_lan failed with rc=%ld\n", lpar_rc);
-               for(i = 0; i < 6; i++) {
-                       ibmveth_error_printk("tx: desc[%i] valid=%d, len=%d, address=0x%d\n", i,
-                                            desc[i].fields.valid, desc[i].fields.length, desc[i].fields.address);
-               }
+               ibmveth_error_printk("tx: valid=%d, len=%d, address=0x%08x\n",
+                                    desc.fields.valid, desc.fields.length, desc.fields.address);
                tx_send_failed++;
                tx_dropped++;
        } else {
@@ -962,11 +902,8 @@ static int ibmveth_start_xmit(struct sk_buff *skb, struct net_device *netdev)
                netdev->trans_start = jiffies;
        }
 
-       do {
-               dma_unmap_single(&adapter->vdev->dev,
-                               desc[nfrags].fields.address,
-                               desc[nfrags].fields.length, DMA_TO_DEVICE);
-       } while(--nfrags >= 0);
+       dma_unmap_single(&adapter->vdev->dev, desc.fields.address,
+                        desc.fields.length, DMA_TO_DEVICE);
 
 out:   spin_lock_irqsave(&adapter->stats_lock, flags);
        adapter->stats.tx_dropped += tx_dropped;
@@ -1366,10 +1303,7 @@ static int ibmveth_seq_show(struct seq_file *seq, void *v)
                   firmware_mac[3], firmware_mac[4], firmware_mac[5]);
 
        seq_printf(seq, "\nAdapter Statistics:\n");
-       seq_printf(seq, "  TX:  skbuffs linearized:          %ld\n", adapter->tx_linearized);
-       seq_printf(seq, "       multi-descriptor sends:      %ld\n", adapter->tx_multidesc_send);
-       seq_printf(seq, "       skb_linearize failures:      %ld\n", adapter->tx_linearize_failed);
-       seq_printf(seq, "       vio_map_single failres:      %ld\n", adapter->tx_map_failed);
+       seq_printf(seq, "  TX:  vio_map_single failres:      %ld\n", adapter->tx_map_failed);
        seq_printf(seq, "       send failures:               %ld\n", adapter->tx_send_failed);
        seq_printf(seq, "  RX:  replenish task cycles:       %ld\n", adapter->replenish_task_cycles);
        seq_printf(seq, "       alloc_skb_failures:          %ld\n", adapter->replenish_no_mem);
index 43b068d..30f9fc6 100644 (file)
@@ -25,8 +25,6 @@
 #ifndef _IBMVETH_H
 #define _IBMVETH_H
 
-#define IbmVethMaxSendFrags 6
-
 /* constants for H_MULTICAST_CTRL */
 #define IbmVethMcastReceptionModifyBit     0x80000UL
 #define IbmVethMcastReceptionEnableBit     0x20000UL
@@ -147,9 +145,6 @@ struct ibmveth_adapter {
     u64 replenish_add_buff_success;
     u64 rx_invalid_buffer;
     u64 rx_no_buffer;
-    u64 tx_multidesc_send;
-    u64 tx_linearized;
-    u64 tx_linearize_failed;
     u64 tx_map_failed;
     u64 tx_send_failed;
     spinlock_t stats_lock;