Re: [PATCH v3 06/18] ibmvfc: add handlers to drain and complete Sub-CRQ responses
From: Brian King <hidden>
Date: 2020-12-04 14:52:46
Also in:
linux-scsi, lkml
On 12/2/20 8:07 PM, Tyrel Datwyler wrote:
quoted hunk ↗ jump to hunk
The logic for iterating over the Sub-CRQ responses is similiar to that of the primary CRQ. Add the necessary handlers for processing those responses. Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com> --- drivers/scsi/ibmvscsi/ibmvfc.c | 80 ++++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+)diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c index e082935f56cf..b61ae1df21e5 100644 --- a/drivers/scsi/ibmvscsi/ibmvfc.c +++ b/drivers/scsi/ibmvscsi/ibmvfc.c@@ -3381,6 +3381,86 @@ static int ibmvfc_toggle_scrq_irq(struct ibmvfc_sub_queue *scrq, int enable) return rc; } +static void ibmvfc_handle_scrq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost) +{ + struct ibmvfc_event *evt = (struct ibmvfc_event *)be64_to_cpu(crq->ioba); + unsigned long flags; + + switch (crq->valid) { + case IBMVFC_CRQ_CMD_RSP: + break; + case IBMVFC_CRQ_XPORT_EVENT: + return; + default: + dev_err(vhost->dev, "Got and invalid message type 0x%02x\n", crq->valid); + return; + } + + /* The only kind of payload CRQs we should get are responses to + * things we send. Make sure this response is to something we + * actually sent + */ + if (unlikely(!ibmvfc_valid_event(&vhost->pool, evt))) { + dev_err(vhost->dev, "Returned correlation_token 0x%08llx is invalid!\n", + crq->ioba); + return; + } + + if (unlikely(atomic_read(&evt->free))) { + dev_err(vhost->dev, "Received duplicate correlation_token 0x%08llx!\n", + crq->ioba); + return; + } + + del_timer(&evt->timer); + list_del(&evt->queue); + ibmvfc_trc_end(evt);> + spin_unlock_irqrestore(vhost->host->host_lock, flags);
You can't do this here... You are grabbing the host lock in ibmvfc_drain_sub_crq and saving the irqflags to a local in that function, then doing a spin_unlock_irqrestore and restoring irqflags using an uninitialized local in this function... I'm assuming this will get sorted out with the locking changes we've been discussing off-list...
+ evt->done(evt);
+ spin_lock_irqsave(vhost->host->host_lock, flags);
+}
+
+static struct ibmvfc_crq *ibmvfc_next_scrq(struct ibmvfc_sub_queue *scrq)
+{
+ struct ibmvfc_crq *crq;
+
+ crq = &scrq->msgs[scrq->cur].crq;
+ if (crq->valid & 0x80) {
+ if (++scrq->cur == scrq->size)
+ scrq->cur = 0;
+ rmb();
+ } else
+ crq = NULL;
+
+ return crq;
+}
+
+static void ibmvfc_drain_sub_crq(struct ibmvfc_sub_queue *scrq)
+{
+ struct ibmvfc_crq *crq;
+ unsigned long flags;
+ int done = 0;
+
+ spin_lock_irqsave(scrq->vhost->host->host_lock, flags);
+ while (!done) {
+ while ((crq = ibmvfc_next_scrq(scrq)) != NULL) {
+ ibmvfc_handle_scrq(crq, scrq->vhost);
+ crq->valid = 0;
+ wmb();
+ }
+
+ ibmvfc_toggle_scrq_irq(scrq, 1);
+ if ((crq = ibmvfc_next_scrq(scrq)) != NULL) {
+ ibmvfc_toggle_scrq_irq(scrq, 0);
+ ibmvfc_handle_scrq(crq, scrq->vhost);
+ crq->valid = 0;
+ wmb();
+ } else
+ done = 1;
+ }
+ spin_unlock_irqrestore(scrq->vhost->host->host_lock, flags);
+}
+
/**
* ibmvfc_init_tgt - Set the next init job step for the target
* @tgt: ibmvfc target struct-- Brian King Power Linux I/O IBM Linux Technology Center