diff mbox series

[net-next,v4,1/4] virtio_ring: enable premapped mode whatever use_dma_api

Message ID 20240508063718.69806-2-xuanzhuo@linux.alibaba.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series virtio_net: rx enable premapped mode by default | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 928 this patch: 928
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 4 of 4 maintainers
netdev/build_clang success Errors and warnings before: 938 this patch: 938
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 939 this patch: 939
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 19 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 22 this patch: 22
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-05-11--03-00 (tests: 1016)

Commit Message

Xuan Zhuo May 8, 2024, 6:37 a.m. UTC
Now, we have virtio DMA APIs, the driver can be the premapped
mode whatever the virtio core uses dma api or not.

So remove the limit of checking use_dma_api from
virtqueue_set_dma_premapped().

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
---
 drivers/virtio/virtio_ring.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

Comments

Larysa Zaremba May 10, 2024, 7:19 a.m. UTC | #1
On Wed, May 08, 2024 at 02:37:15PM +0800, Xuan Zhuo wrote:
> Now, we have virtio DMA APIs, the driver can be the premapped
> mode whatever the virtio core uses dma api or not.
> 
> So remove the limit of checking use_dma_api from
> virtqueue_set_dma_premapped().
> 
> Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> Acked-by: Jason Wang <jasowang@redhat.com>
> ---
>  drivers/virtio/virtio_ring.c | 7 +------
>  1 file changed, 1 insertion(+), 6 deletions(-)
> 
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 6f7e5010a673..85d0dc26ae9f 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -2782,7 +2782,7 @@ EXPORT_SYMBOL_GPL(virtqueue_resize);
>   *
>   * Returns zero or a negative error.
>   * 0: success.
> - * -EINVAL: vring does not use the dma api, so we can not enable premapped mode.
> + * -EINVAL: the vq is in use.

To me it sounds more like -EBUSY with the current error description.
But I suspect that the error is returned, when the following condition is not 
met:

* This function must be called immediately after creating the vq, or after vq 
* reset, and before adding any buffers to it.

If I am not mistaking, then a better way to put it would be:
* -EINVAL: too late to enable premapped mode, the vq already contains buffers

>   */
>  int virtqueue_set_dma_premapped(struct virtqueue *_vq)
>  {
> @@ -2798,11 +2798,6 @@ int virtqueue_set_dma_premapped(struct virtqueue *_vq)
>  		return -EINVAL;
>  	}
>  
> -	if (!vq->use_dma_api) {
> -		END_USE(vq);
> -		return -EINVAL;
> -	}
> -
>  	vq->premapped = true;
>  	vq->do_unmap = false;
>  
> -- 
> 2.32.0.3.g01195cf9f
> 
>
diff mbox series

Patch

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 6f7e5010a673..85d0dc26ae9f 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -2782,7 +2782,7 @@  EXPORT_SYMBOL_GPL(virtqueue_resize);
  *
  * Returns zero or a negative error.
  * 0: success.
- * -EINVAL: vring does not use the dma api, so we can not enable premapped mode.
+ * -EINVAL: the vq is in use.
  */
 int virtqueue_set_dma_premapped(struct virtqueue *_vq)
 {
@@ -2798,11 +2798,6 @@  int virtqueue_set_dma_premapped(struct virtqueue *_vq)
 		return -EINVAL;
 	}
 
-	if (!vq->use_dma_api) {
-		END_USE(vq);
-		return -EINVAL;
-	}
-
 	vq->premapped = true;
 	vq->do_unmap = false;