Changeset 417aaafb in mainline for uspace/lib/virtio/virtio.c

Timestamp:

2018-06-25T21:37:48Z (6 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

e3107e2

Parents:

ea6840d

Message:

Protect the virtqueue with a mutex

File:

• uspace/lib/virtio/virtio.c (modified) (5 diffs)

uspace/lib/virtio/virtio.c

@@ -63 +63 @@
         virtq_t *q = &vdev->queues[num];
 
+        fibril_mutex_lock(&q->lock);
         uint16_t idx = pio_read_le16(&q->avail->idx);
         pio_write_le16(&q->avail->ring[idx % q->queue_size], descno);
@@ -69 +70 @@
         write_barrier();
         pio_write_le16(q->notify, num);
+        fibril_mutex_unlock(&q->lock);
 }
 
@@ -76 +78 @@
         virtq_t *q = &vdev->queues[num];
 
+        fibril_mutex_lock(&q->lock);
         uint16_t last_idx = q->used_last_idx % q->queue_size;
-        if (last_idx == (pio_read_le16(&q->used->idx) % q->queue_size))
+        if (last_idx == (pio_read_le16(&q->used->idx) % q->queue_size)) {
+                fibril_mutex_unlock(&q->lock);
                 return false;
+        }
 
         *descno = (uint16_t) pio_read_le32(&q->used->ring[last_idx].id);
@@ -84 +89 @@
 
         q->used_last_idx++;
+        fibril_mutex_unlock(&q->lock);
 
         return true;
@@ -132 +138 @@
         }
 
+        fibril_mutex_initialize(&q->lock);
+
         q->size = mem_size;
         q->queue_size = size;