Merge tag 'mips-fixes_5.14_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips...

[linux-2.6-microblaze.git] / drivers / scsi / ibmvscsi / ibmvfc.c

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index bee1bec..935b01e 100644 (file)
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -807,6 +807,13 @@ static int ibmvfc_init_event_pool(struct ibmvfc_host *vhost,
        for (i = 0; i < size; ++i) {
                struct ibmvfc_event *evt = &pool->events[i];
 
+               /*
+                * evt->active states
+                *  1 = in flight
+                *  0 = being completed
+                * -1 = free/freed
+                */
+               atomic_set(&evt->active, -1);
                atomic_set(&evt->free, 1);
                evt->crq.valid = 0x80;
                evt->crq.ioba = cpu_to_be64(pool->iu_token + (sizeof(*evt->xfer_iu) * i));
@@ -1017,6 +1024,7 @@ static void ibmvfc_free_event(struct ibmvfc_event *evt)
 
        BUG_ON(!ibmvfc_valid_event(pool, evt));
        BUG_ON(atomic_inc_return(&evt->free) != 1);
+       BUG_ON(atomic_dec_and_test(&evt->active));
 
        spin_lock_irqsave(&evt->queue->l_lock, flags);
        list_add_tail(&evt->queue_list, &evt->queue->free);
@@ -1072,6 +1080,12 @@ static void ibmvfc_complete_purge(struct list_head *purge_list)
  **/
 static void ibmvfc_fail_request(struct ibmvfc_event *evt, int error_code)
 {
+       /*
+        * Anything we are failing should still be active. Otherwise, it
+        * implies we already got a response for the command and are doing
+        * something bad like double completing it.
+        */
+       BUG_ON(!atomic_dec_and_test(&evt->active));
        if (evt->cmnd) {
                evt->cmnd->result = (error_code << 16);
                evt->done = ibmvfc_scsi_eh_done;
@@ -1723,6 +1737,7 @@ static int ibmvfc_send_event(struct ibmvfc_event *evt,
 
                evt->done(evt);
        } else {
+               atomic_set(&evt->active, 1);
                spin_unlock_irqrestore(&evt->queue->l_lock, flags);
                ibmvfc_trc_start(evt);
        }
@@ -3251,7 +3266,7 @@ static void ibmvfc_handle_crq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost,
                return;
        }
 
-       if (unlikely(atomic_read(&evt->free))) {
+       if (unlikely(atomic_dec_if_positive(&evt->active))) {
                dev_err(vhost->dev, "Received duplicate correlation_token 0x%08llx!\n",
                        crq->ioba);
                return;
@@ -3778,7 +3793,7 @@ static void ibmvfc_handle_scrq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost
                return;
        }
 
-       if (unlikely(atomic_read(&evt->free))) {
+       if (unlikely(atomic_dec_if_positive(&evt->active))) {
                dev_err(vhost->dev, "Received duplicate correlation_token 0x%08llx!\n",
                        crq->ioba);
                return;