s390: qeth driver fixes: atomic context fixups

    - qeth device functions were not callable
      in atomic context due to usage of wait_event_xxx operations in qeth.
      "schedule while atomic" message appeared and kernel dumped when
      removing slave from bond device.

Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

2 files changed, 30 insertions, 97 deletions

diff --git a/drivers/s390/net/qeth.h b/drivers/s390/net/qeth.h
index 53c358c7d368..e95c281f1e36 100644
--- a/drivers/s390/net/qeth.h
+++ b/drivers/s390/net/qeth.h
@@ -710,7 +710,7 @@ struct qeth_reply {
         int (*callback)(struct qeth_card *,struct qeth_reply *,unsigned long);
         u32 seqno;
         unsigned long offset;
-        int received;
+        atomic_t received;
         int rc;
         void *param;
         struct qeth_card *card;
diff --git a/drivers/s390/net/qeth_main.c b/drivers/s390/net/qeth_main.c
index bfc37bae19bc..d2efa5ff125d 100644
--- a/drivers/s390/net/qeth_main.c
+++ b/drivers/s390/net/qeth_main.c
@@ -471,7 +471,7 @@ qeth_irq(struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
             channel->state == CH_STATE_UP)
                 qeth_issue_next_read(card);
 
-        tasklet_schedule(&channel->irq_tasklet);
+        qeth_irq_tasklet((unsigned long)channel);
         return;
 out:
         wake_up(&card->wait_q);
@@ -951,40 +951,6 @@ qeth_do_run_thread(struct qeth_card *card, unsigned long thread)
 }
 
 static int
-qeth_register_ip_addresses(void *ptr)
-{
-        struct qeth_card *card;
-
-        card = (struct qeth_card *) ptr;
-        daemonize("qeth_reg_ip");
-        QETH_DBF_TEXT(trace,4,"regipth1");
-        if (!qeth_do_run_thread(card, QETH_SET_IP_THREAD))
-                return 0;
-        QETH_DBF_TEXT(trace,4,"regipth2");
-        qeth_set_ip_addr_list(card);
-        qeth_clear_thread_running_bit(card, QETH_SET_IP_THREAD);
-        return 0;
-}
-
-/*
- * Drive the SET_PROMISC_MODE thread
- */
-static int
-qeth_set_promisc_mode(void *ptr)
-{
-        struct qeth_card *card = (struct qeth_card *) ptr;
-
-        daemonize("qeth_setprm");
-        QETH_DBF_TEXT(trace,4,"setprm1");
-        if (!qeth_do_run_thread(card, QETH_SET_PROMISC_MODE_THREAD))
-                return 0;
-        QETH_DBF_TEXT(trace,4,"setprm2");
-        qeth_setadp_promisc_mode(card);
-        qeth_clear_thread_running_bit(card, QETH_SET_PROMISC_MODE_THREAD);
-        return 0;
-}
-
-static int
 qeth_recover(void *ptr)
 {
         struct qeth_card *card;
@@ -1047,11 +1013,6 @@ qeth_start_kernel_thread(struct work_struct *work)
         if (card->read.state != CH_STATE_UP &&
             card->write.state != CH_STATE_UP)
                 return;
-
-        if (qeth_do_start_thread(card, QETH_SET_IP_THREAD))
-                kernel_thread(qeth_register_ip_addresses, (void *)card,SIGCHLD);
-        if (qeth_do_start_thread(card, QETH_SET_PROMISC_MODE_THREAD))
-                kernel_thread(qeth_set_promisc_mode, (void *)card, SIGCHLD);
         if (qeth_do_start_thread(card, QETH_RECOVER_THREAD))
                 kernel_thread(qeth_recover, (void *) card, SIGCHLD);
 }
@@ -1613,8 +1574,6 @@ qeth_issue_next_read(struct qeth_card *card)
                 return -ENOMEM;
         }
         qeth_setup_ccw(&card->read, iob->data, QETH_BUFSIZE);
-        wait_event(card->wait_q,
-                   atomic_cmpxchg(&card->read.irq_pending, 0, 1) == 0);
         QETH_DBF_TEXT(trace, 6, "noirqpnd");
         rc = ccw_device_start(card->read.ccwdev, &card->read.ccw,
                               (addr_t) iob, 0, 0);
@@ -1635,6 +1594,7 @@ qeth_alloc_reply(struct qeth_card *card)
         reply = kzalloc(sizeof(struct qeth_reply), GFP_ATOMIC);
         if (reply){
                 atomic_set(&reply->refcnt, 1);
+                atomic_set(&reply->received, 0);
                 reply->card = card;
         };
         return reply;
@@ -1655,31 +1615,6 @@ qeth_put_reply(struct qeth_reply *reply)
                 kfree(reply);
 }
 
-static void
-qeth_cmd_timeout(unsigned long data)
-{
-        struct qeth_reply *reply, *list_reply, *r;
-        unsigned long flags;
-
-        reply = (struct qeth_reply *) data;
-        spin_lock_irqsave(&reply->card->lock, flags);
-        list_for_each_entry_safe(list_reply, r,
-                                 &reply->card->cmd_waiter_list, list) {
-                if (reply == list_reply){
-                        qeth_get_reply(reply);
-                        list_del_init(&reply->list);
-                        spin_unlock_irqrestore(&reply->card->lock, flags);
-                        reply->rc = -ETIME;
-                        reply->received = 1;
-                        wake_up(&reply->wait_q);
-                        qeth_put_reply(reply);
-                        return;
-                }
-        }
-        spin_unlock_irqrestore(&reply->card->lock, flags);
-}
-
-
 static struct qeth_ipa_cmd *
 qeth_check_ipa_data(struct qeth_card *card, struct qeth_cmd_buffer *iob)
 {
@@ -1745,7 +1680,7 @@ qeth_clear_ipacmd_list(struct qeth_card *card)
         list_for_each_entry_safe(reply, r, &card->cmd_waiter_list, list) {
                 qeth_get_reply(reply);
                 reply->rc = -EIO;
-                reply->received = 1;
+                atomic_inc(&reply->received);
                 list_del_init(&reply->list);
                 wake_up(&reply->wait_q);
                 qeth_put_reply(reply);
@@ -1814,7 +1749,7 @@ qeth_send_control_data_cb(struct qeth_channel *channel,
                                               &card->cmd_waiter_list);
                                 spin_unlock_irqrestore(&card->lock, flags);
                         } else {
-                                reply->received = 1;
+                                atomic_inc(&reply->received);
                                 wake_up(&reply->wait_q);
                         }
                         qeth_put_reply(reply);
@@ -1858,7 +1793,7 @@ qeth_send_control_data(struct qeth_card *card, int len,
         int rc;
         unsigned long flags;
         struct qeth_reply *reply = NULL;
-        struct timer_list timer;
+        unsigned long timeout;
 
         QETH_DBF_TEXT(trace, 2, "sendctl");
 
@@ -1873,21 +1808,20 @@ qeth_send_control_data(struct qeth_card *card, int len,
                 reply->seqno = QETH_IDX_COMMAND_SEQNO;
         else
                 reply->seqno = card->seqno.ipa++;
-        init_timer(&timer);
-        timer.function = qeth_cmd_timeout;
-        timer.data = (unsigned long) reply;
         init_waitqueue_head(&reply->wait_q);
         spin_lock_irqsave(&card->lock, flags);
         list_add_tail(&reply->list, &card->cmd_waiter_list);
         spin_unlock_irqrestore(&card->lock, flags);
         QETH_DBF_HEX(control, 2, iob->data, QETH_DBF_CONTROL_LEN);
-        wait_event(card->wait_q,
-                   atomic_cmpxchg(&card->write.irq_pending, 0, 1) == 0);
+
+        while (atomic_cmpxchg(&card->write.irq_pending, 0, 1)) ;
         qeth_prepare_control_data(card, len, iob);
+
         if (IS_IPA(iob->data))
-                timer.expires = jiffies + QETH_IPA_TIMEOUT;
+                timeout = jiffies + QETH_IPA_TIMEOUT;
         else
-                timer.expires = jiffies + QETH_TIMEOUT;
+                timeout = jiffies + QETH_TIMEOUT;
+
         QETH_DBF_TEXT(trace, 6, "noirqpnd");
         spin_lock_irqsave(get_ccwdev_lock(card->write.ccwdev), flags);
         rc = ccw_device_start(card->write.ccwdev, &card->write.ccw,
@@ -1906,9 +1840,16 @@ qeth_send_control_data(struct qeth_card *card, int len,
                 wake_up(&card->wait_q);
                 return rc;
         }
-        add_timer(&timer);
-        wait_event(reply->wait_q, reply->received);
-        del_timer_sync(&timer);
+        while (!atomic_read(&reply->received)) {
+                if (time_after(jiffies, timeout)) {
+                        spin_lock_irqsave(&reply->card->lock, flags);
+                        list_del_init(&reply->list);
+                        spin_unlock_irqrestore(&reply->card->lock, flags);
+                        reply->rc = -ETIME;
+                        atomic_inc(&reply->received);
+                        wake_up(&reply->wait_q);
+                }
+        };
         rc = reply->rc;
         qeth_put_reply(reply);
         return rc;
@@ -5541,12 +5482,10 @@ qeth_set_multicast_list(struct net_device *dev)
         qeth_add_multicast_ipv6(card);
 #endif
 out:
-        if (qeth_set_thread_start_bit(card, QETH_SET_IP_THREAD) == 0)
-                schedule_work(&card->kernel_thread_starter);
+        qeth_set_ip_addr_list(card);
         if (!qeth_adp_supported(card, IPA_SETADP_SET_PROMISC_MODE))
                 return;
-        if (qeth_set_thread_start_bit(card, QETH_SET_PROMISC_MODE_THREAD)==0)
-                schedule_work(&card->kernel_thread_starter);
+        qeth_setadp_promisc_mode(card);
 }
 
 static int
@@ -8271,8 +8210,7 @@ qeth_add_vipa(struct qeth_card *card, enum qeth_prot_versions proto,
         }
         if (!qeth_add_ip(card, ipaddr))
                 kfree(ipaddr);
-        if (qeth_set_thread_start_bit(card, QETH_SET_IP_THREAD) == 0)
-                schedule_work(&card->kernel_thread_starter);
+        qeth_set_ip_addr_list(card);
         return rc;
 }
 
@@ -8300,8 +8238,7 @@ qeth_del_vipa(struct qeth_card *card, enum qeth_prot_versions proto,
                 return;
         if (!qeth_delete_ip(card, ipaddr))
                 kfree(ipaddr);
-        if (qeth_set_thread_start_bit(card, QETH_SET_IP_THREAD) == 0)
-                schedule_work(&card->kernel_thread_starter);
+        qeth_set_ip_addr_list(card);
 }
 
 /*
@@ -8344,8 +8281,7 @@ qeth_add_rxip(struct qeth_card *card, enum qeth_prot_versions proto,
         }
         if (!qeth_add_ip(card, ipaddr))
                 kfree(ipaddr);
-        if (qeth_set_thread_start_bit(card, QETH_SET_IP_THREAD) == 0)
-                schedule_work(&card->kernel_thread_starter);
+        qeth_set_ip_addr_list(card);
         return 0;
 }
 
@@ -8373,8 +8309,7 @@ qeth_del_rxip(struct qeth_card *card, enum qeth_prot_versions proto,
                 return;
         if (!qeth_delete_ip(card, ipaddr))
                 kfree(ipaddr);
-        if (qeth_set_thread_start_bit(card, QETH_SET_IP_THREAD) == 0)
-                schedule_work(&card->kernel_thread_starter);
+        qeth_set_ip_addr_list(card);
 }
 
 /**
@@ -8416,8 +8351,7 @@ qeth_ip_event(struct notifier_block *this,
         default:
                 break;
         }
-        if (qeth_set_thread_start_bit(card, QETH_SET_IP_THREAD) == 0)
-                schedule_work(&card->kernel_thread_starter);
+        qeth_set_ip_addr_list(card);
 out:
         return NOTIFY_DONE;
 }
@@ -8469,8 +8403,7 @@ qeth_ip6_event(struct notifier_block *this,
         default:
                 break;
         }
-        if (qeth_set_thread_start_bit(card, QETH_SET_IP_THREAD) == 0)
-                schedule_work(&card->kernel_thread_starter);
+        qeth_set_ip_addr_list(card);
 out:
         return NOTIFY_DONE;
 }