qeth: remove dev_queue_xmit invocation

For a certain Hipersockets specific error code in the xmit path, the
qeth driver tries to invoke dev_queue_xmit again.
Commit 79640a4ca6955e3ebdb7038508fa7a0cd7fa5527 introduces a busylock
causing locking problems in case of re-invoked dev_queue_xmit by qeth.
This patch removes the attempts to retry packet sending with
dev_queue_xmit from the qeth driver.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 8 insertions, 54 deletions

diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index 6be43eb126b4..f47a714538db 100644
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -440,7 +440,6 @@ struct qeth_qdio_out_q {
          * index of buffer to be filled by driver; state EMPTY or PACKING
          */
         int next_buf_to_fill;
-        int sync_iqdio_error;
         /*
          * number of buffers that are currently filled (PRIMED)
          * -> these buffers are hardware-owned
@@ -695,14 +694,6 @@ struct qeth_mc_mac {
         int is_vmac;
 };
 
-struct qeth_skb_data {
-        __u32 magic;
-        int count;
-};
-
-#define QETH_SKB_MAGIC 0x71657468
-#define QETH_SIGA_CC2_RETRIES 3
-
 struct qeth_rx {
         int b_count;
         int b_index;
diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 764267062601..09ab6a2d3e49 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -877,8 +877,8 @@ out:
         return;
 }
 
-static void __qeth_clear_output_buffer(struct qeth_qdio_out_q *queue,
-                 struct qeth_qdio_out_buffer *buf, unsigned int qeth_skip_skb)
+static void qeth_clear_output_buffer(struct qeth_qdio_out_q *queue,
+                struct qeth_qdio_out_buffer *buf)
 {
         int i;
         struct sk_buff *skb;
@@ -887,13 +887,11 @@ static void __qeth_clear_output_buffer(struct qeth_qdio_out_q *queue,
         if (buf->buffer->element[0].flags & 0x40)
                 atomic_dec(&queue->set_pci_flags_count);
 
-        if (!qeth_skip_skb) {
+        skb = skb_dequeue(&buf->skb_list);
+        while (skb) {
+                atomic_dec(&skb->users);
+                dev_kfree_skb_any(skb);
                 skb = skb_dequeue(&buf->skb_list);
-                while (skb) {
-                        atomic_dec(&skb->users);
-                        dev_kfree_skb_any(skb);
-                        skb = skb_dequeue(&buf->skb_list);
-                }
         }
         for (i = 0; i < QETH_MAX_BUFFER_ELEMENTS(queue->card); ++i) {
                 if (buf->buffer->element[i].addr && buf->is_header[i])
@@ -909,12 +907,6 @@ static void __qeth_clear_output_buffer(struct qeth_qdio_out_q *queue,
         atomic_set(&buf->state, QETH_QDIO_BUF_EMPTY);
 }
 
-static void qeth_clear_output_buffer(struct qeth_qdio_out_q *queue,
-                struct qeth_qdio_out_buffer *buf)
-{
-        __qeth_clear_output_buffer(queue, buf, 0);
-}
-
 void qeth_clear_qdio_buffers(struct qeth_card *card)
 {
         int i, j;
@@ -2833,7 +2825,6 @@ static void qeth_flush_buffers(struct qeth_qdio_out_q *queue, int index,
                 }
         }
 
-        queue->sync_iqdio_error = 0;
         queue->card->dev->trans_start = jiffies;
         if (queue->card->options.performance_stats) {
                 queue->card->perf_stats.outbound_do_qdio_cnt++;
@@ -2849,10 +2840,6 @@ static void qeth_flush_buffers(struct qeth_qdio_out_q *queue, int index,
                 queue->card->perf_stats.outbound_do_qdio_time +=
                         qeth_get_micros() -
                         queue->card->perf_stats.outbound_do_qdio_start_time;
-        if (rc > 0) {
-                if (!(rc & QDIO_ERROR_SIGA_BUSY))
-                        queue->sync_iqdio_error = rc & 3;
-        }
         if (rc) {
                 queue->card->stats.tx_errors += count;
                 /* ignore temporary SIGA errors without busy condition */
@@ -2940,7 +2927,6 @@ void qeth_qdio_output_handler(struct ccw_device *ccwdev,
         struct qeth_qdio_out_q *queue = card->qdio.out_qs[__queue];
         struct qeth_qdio_out_buffer *buffer;
         int i;
-        unsigned qeth_send_err;
 
         QETH_CARD_TEXT(card, 6, "qdouhdl");
         if (qdio_error & QDIO_ERROR_ACTIVATE_CHECK_CONDITION) {
@@ -2956,9 +2942,8 @@ void qeth_qdio_output_handler(struct ccw_device *ccwdev,
         }
         for (i = first_element; i < (first_element + count); ++i) {
                 buffer = &queue->bufs[i % QDIO_MAX_BUFFERS_PER_Q];
-                qeth_send_err = qeth_handle_send_error(card, buffer, qdio_error);
-                __qeth_clear_output_buffer(queue, buffer,
-                        (qeth_send_err == QETH_SEND_ERROR_RETRY) ? 1 : 0);
+                qeth_handle_send_error(card, buffer, qdio_error);
+                qeth_clear_output_buffer(queue, buffer);
         }
         atomic_sub(count, &queue->used_buffers);
         /* check if we need to do something on this outbound queue */
@@ -3183,10 +3168,7 @@ int qeth_do_send_packet_fast(struct qeth_card *card,
                 int offset, int hd_len)
 {
         struct qeth_qdio_out_buffer *buffer;
-        struct sk_buff *skb1;
-        struct qeth_skb_data *retry_ctrl;
         int index;
-        int rc;
 
         /* spin until we get the queue ... */
         while (atomic_cmpxchg(&queue->state, QETH_OUT_Q_UNLOCKED,
@@ -3205,25 +3187,6 @@ int qeth_do_send_packet_fast(struct qeth_card *card,
         atomic_set(&queue->state, QETH_OUT_Q_UNLOCKED);
         qeth_fill_buffer(queue, buffer, skb, hdr, offset, hd_len);
         qeth_flush_buffers(queue, index, 1);
-        if (queue->sync_iqdio_error == 2) {
-                skb1 = skb_dequeue(&buffer->skb_list);
-                while (skb1) {
-                        atomic_dec(&skb1->users);
-                        skb1 = skb_dequeue(&buffer->skb_list);
-                }
-                retry_ctrl = (struct qeth_skb_data *) &skb->cb[16];
-                if (retry_ctrl->magic != QETH_SKB_MAGIC) {
-                        retry_ctrl->magic = QETH_SKB_MAGIC;
-                        retry_ctrl->count = 0;
-                }
-                if (retry_ctrl->count < QETH_SIGA_CC2_RETRIES) {
-                        retry_ctrl->count++;
-                        rc = dev_queue_xmit(skb);
-                } else {
-                        dev_kfree_skb_any(skb);
-                        QETH_CARD_TEXT(card, 2, "qrdrop");
-                }
-        }
         return 0;
 out:
         atomic_set(&queue->state, QETH_OUT_Q_UNLOCKED);