virtio_pci: Use the DMA API if enabled

[deliverable/linux.git] / drivers / virtio / virtio_pci_modern.c

diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
index 7760fc1a2218e9ea9e053caf8db2be27dc8d2952..f6f28cc7eb45765af6db2f4fa2a41de6fcbecf05 100644 (file)
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -287,31 +287,6 @@ static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector)
        return vp_ioread16(&vp_dev->common->msix_config);
 }
 
-static size_t vring_pci_size(u16 num)
-{
-       /* We only need a cacheline separation. */
-       return PAGE_ALIGN(vring_size(num, SMP_CACHE_BYTES));
-}
-
-static void *alloc_virtqueue_pages(int *num)
-{
-       void *pages;
-
-       /* TODO: allocate each queue chunk individually */
-       for (; *num && vring_pci_size(*num) > PAGE_SIZE; *num /= 2) {
-               pages = alloc_pages_exact(vring_pci_size(*num),
-                                         GFP_KERNEL|__GFP_ZERO|__GFP_NOWARN);
-               if (pages)
-                       return pages;
-       }
-
-       if (!*num)
-               return NULL;
-
-       /* Try to get a single page. You are my only hope! */
-       return alloc_pages_exact(vring_pci_size(*num), GFP_KERNEL|__GFP_ZERO);
-}
-
 static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
                                  struct virtio_pci_vq_info *info,
                                  unsigned index,
@@ -343,29 +318,22 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
        /* get offset of notification word for this vq */
        off = vp_ioread16(&cfg->queue_notify_off);
 
-       info->num = num;
        info->msix_vector = msix_vec;
 
-       info->queue = alloc_virtqueue_pages(&info->num);
-       if (info->queue == NULL)
-               return ERR_PTR(-ENOMEM);
-
        /* create the vring */
-       vq = vring_new_virtqueue(index, info->num,
-                                SMP_CACHE_BYTES, &vp_dev->vdev,
-                                true, info->queue, vp_notify, callback, name);
-       if (!vq) {
-               err = -ENOMEM;
-               goto err_new_queue;
-       }
+       vq = vring_create_virtqueue(index, num,
+                                   SMP_CACHE_BYTES, &vp_dev->vdev,
+                                   true, true, vp_notify, callback, name);
+       if (!vq)
+               return ERR_PTR(-ENOMEM);
 
        /* activate the queue */
-       vp_iowrite16(num, &cfg->queue_size);
-       vp_iowrite64_twopart(virt_to_phys(info->queue),
+       vp_iowrite16(virtqueue_get_vring_size(vq), &cfg->queue_size);
+       vp_iowrite64_twopart(virtqueue_get_desc_addr(vq),
                             &cfg->queue_desc_lo, &cfg->queue_desc_hi);
-       vp_iowrite64_twopart(virt_to_phys(virtqueue_get_avail(vq)),
+       vp_iowrite64_twopart(virtqueue_get_avail_addr(vq),
                             &cfg->queue_avail_lo, &cfg->queue_avail_hi);
-       vp_iowrite64_twopart(virt_to_phys(virtqueue_get_used(vq)),
+       vp_iowrite64_twopart(virtqueue_get_used_addr(vq),
                             &cfg->queue_used_lo, &cfg->queue_used_hi);
 
        if (vp_dev->notify_base) {
@@ -410,8 +378,6 @@ err_assign_vector:
                pci_iounmap(vp_dev->pci_dev, (void __iomem __force *)vq->priv);
 err_map_notify:
        vring_del_virtqueue(vq);
-err_new_queue:
-       free_pages_exact(info->queue, vring_pci_size(info->num));
        return ERR_PTR(err);
 }
 
@@ -456,8 +422,6 @@ static void del_vq(struct virtio_pci_vq_info *info)
                pci_iounmap(vp_dev->pci_dev, (void __force __iomem *)vq->priv);
 
        vring_del_virtqueue(vq);
-
-       free_pages_exact(info->queue, vring_pci_size(info->num));
 }
 
 static const struct virtio_config_ops virtio_pci_config_nodev_ops = {
@@ -641,6 +605,13 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
                return -EINVAL;
        }
 
+       err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64));
+       if (err)
+               err = dma_set_mask_and_coherent(&pci_dev->dev,
+                                               DMA_BIT_MASK(32));
+       if (err)
+               dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA.  Trying to continue, but this might not work.\n");
+
        /* Device capability is only mandatory for devices that have
         * device-specific configuration.
         */