1 files changed, 70 insertions, 22 deletions

diff --git a/drivers/dma/idxd/submit.c b/drivers/dma/idxd/submit.c
index 19afb62abaff..36c9c1a89b7e 100644
--- a/drivers/dma/idxd/submit.c
+++ b/drivers/dma/idxd/submit.c
@@ -25,11 +25,10 @@ static struct idxd_desc *__get_desc(struct idxd_wq *wq, int idx, int cpu)
 	 * Descriptor completion vectors are 1...N for MSIX. We will round
 	 * robin through the N vectors.
 	 */
-	wq->vec_ptr = (wq->vec_ptr % idxd->num_wq_irqs) + 1;
+	wq->vec_ptr = desc->vector = (wq->vec_ptr % idxd->num_wq_irqs) + 1;
 	if (!idxd->int_handles) {
 		desc->hw->int_handle = wq->vec_ptr;
 	} else {
-		desc->vector = wq->vec_ptr;
 		/*
 		 * int_handles are only for descriptor completion. However for device
 		 * MSIX enumeration, vec 0 is used for misc interrupts. Therefore even
@@ -88,9 +87,64 @@ void idxd_free_desc(struct idxd_wq *wq, struct idxd_desc *desc)
 	sbitmap_queue_clear(&wq->sbq, desc->id, cpu);
 }
 
+static struct idxd_desc *list_abort_desc(struct idxd_wq *wq, struct idxd_irq_entry *ie,
+					 struct idxd_desc *desc)
+{
+	struct idxd_desc *d, *n;
+
+	lockdep_assert_held(&ie->list_lock);
+	list_for_each_entry_safe(d, n, &ie->work_list, list) {
+		if (d == desc) {
+			list_del(&d->list);
+			return d;
+		}
+	}
+
+	/*
+	 * At this point, the desc needs to be aborted is held by the completion
+	 * handler where it has taken it off the pending list but has not added to the
+	 * work list. It will be cleaned up by the interrupt handler when it sees the
+	 * IDXD_COMP_DESC_ABORT for completion status.
+	 */
+	return NULL;
+}
+
+static void llist_abort_desc(struct idxd_wq *wq, struct idxd_irq_entry *ie,
+			     struct idxd_desc *desc)
+{
+	struct idxd_desc *d, *t, *found = NULL;
+	struct llist_node *head;
+	unsigned long flags;
+
+	desc->completion->status = IDXD_COMP_DESC_ABORT;
+	/*
+	 * Grab the list lock so it will block the irq thread handler. This allows the
+	 * abort code to locate the descriptor need to be aborted.
+	 */
+	spin_lock_irqsave(&ie->list_lock, flags);
+	head = llist_del_all(&ie->pending_llist);
+	if (head) {
+		llist_for_each_entry_safe(d, t, head, llnode) {
+			if (d == desc) {
+				found = desc;
+				continue;
+			}
+			list_add_tail(&desc->list, &ie->work_list);
+		}
+	}
+
+	if (!found)
+		found = list_abort_desc(wq, ie, desc);
+	spin_unlock_irqrestore(&ie->list_lock, flags);
+
+	if (found)
+		complete_desc(found, IDXD_COMPLETE_ABORT);
+}
+
 int idxd_submit_desc(struct idxd_wq *wq, struct idxd_desc *desc)
 {
 	struct idxd_device *idxd = wq->idxd;
+	struct idxd_irq_entry *ie = NULL;
 	void __iomem *portal;
 	int rc;
 
@@ -108,6 +162,16 @@ int idxd_submit_desc(struct idxd_wq *wq, struct idxd_desc *desc)
 	 * even on UP because the recipient is a device.
 	 */
 	wmb();
+
+	/*
+	 * Pending the descriptor to the lockless list for the irq_entry
+	 * that we designated the descriptor to.
+	 */
+	if (desc->hw->flags & IDXD_OP_FLAG_RCI) {
+		ie = &idxd->irq_entries[desc->vector];
+		llist_add(&desc->llnode, &ie->pending_llist);
+	}
+
 	if (wq_dedicated(wq)) {
 		iosubmit_cmds512(portal, desc->hw, 1);
 	} else {
@@ -118,29 +182,13 @@ int idxd_submit_desc(struct idxd_wq *wq, struct idxd_desc *desc)
 		 * device is not accepting descriptor at all.
 		 */
 		rc = enqcmds(portal, desc->hw);
-		if (rc < 0)
+		if (rc < 0) {
+			if (ie)
+				llist_abort_desc(wq, ie, desc);
 			return rc;
+		}
 	}
 
 	percpu_ref_put(&wq->wq_active);
-
-	/*
-	 * Pending the descriptor to the lockless list for the irq_entry
-	 * that we designated the descriptor to.
-	 */
-	if (desc->hw->flags & IDXD_OP_FLAG_RCI) {
-		int vec;
-
-		/*
-		 * If the driver is on host kernel, it would be the value
-		 * assigned to interrupt handle, which is index for MSIX
-		 * vector. If it's guest then can't use the int_handle since
-		 * that is the index to IMS for the entire device. The guest
-		 * device local index will be used.
-		 */
-		vec = !idxd->int_handles ? desc->hw->int_handle : desc->vector;
-		llist_add(&desc->llnode, &idxd->irq_entries[vec].pending_llist);
-	}
-
 	return 0;
 }