[PATCH net-next v8 03/15] libeth: allow to create fill queues without NAPI

From: Pavan Kumar Linga <[email protected]>

Control queues can utilize libeth_rx fill queues, despite working outside
of NAPI context. The only problem is standard fill queues requiring NAPI
that provides them with the device pointer.

Introduce a way to provide the device directly without using NAPI.

Suggested-by: Alexander Lobakin <[email protected]>
Reviewed-by: Maciej Fijalkowski <[email protected]>
Signed-off-by: Pavan Kumar Linga <[email protected]>
Tested-by: Bharath R <[email protected]>
Tested-by: Samuel Salin <[email protected]>
Signed-off-by: Larysa Zaremba <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>
---
 drivers/net/ethernet/intel/libeth/rx.c | 12 ++++++++----
 include/net/libeth/rx.h                |  4 +++-
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/intel/libeth/rx.c b/drivers/net/ethernet/intel/libeth/rx.c
index 62521a1f4ec9..0c1a565a1b3a 100644
--- a/drivers/net/ethernet/intel/libeth/rx.c
+++ b/drivers/net/ethernet/intel/libeth/rx.c
@@ -145,25 +145,29 @@ static bool libeth_rx_page_pool_params_zc(struct libeth_fq *fq,
 /**
  * libeth_rx_fq_create - create a PP with the default libeth settings
  * @fq: buffer queue struct to fill
- * @napi: &napi_struct covering this PP (no usage outside its poll loops)
+ * @napi_dev: &napi_struct for NAPI (data) queues, &device for others
  *
  * Return: %0 on success, -%errno on failure.
  */
-int libeth_rx_fq_create(struct libeth_fq *fq, struct napi_struct *napi)
+int libeth_rx_fq_create(struct libeth_fq *fq, void *napi_dev)
 {
+	struct napi_struct *napi = fq->no_napi ? NULL : napi_dev;
 	struct page_pool_params pp = {
 		.flags		= PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV,
 		.order		= LIBETH_RX_PAGE_ORDER,
 		.pool_size	= fq->count,
 		.nid		= fq->nid,
-		.dev		= napi->dev->dev.parent,
-		.netdev		= napi->dev,
+		.dev		= napi ? napi->dev->dev.parent : napi_dev,
+		.netdev		= napi ? napi->dev : NULL,
 		.napi		= napi,
 	};
 	struct libeth_fqe *fqes;
 	struct page_pool *pool;
 	int ret;
 
+	if (!pp.netdev && fq->type == LIBETH_FQE_MTU)
+		return -EINVAL;
+
 	pp.dma_dir = fq->xdp ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE;
 
 	if (!fq->hsplit)
diff --git a/include/net/libeth/rx.h b/include/net/libeth/rx.h
index 5d991404845e..0e736846c5e8 100644
--- a/include/net/libeth/rx.h
+++ b/include/net/libeth/rx.h
@@ -69,6 +69,7 @@ enum libeth_fqe_type {
  * @type: type of the buffers this queue has
  * @hsplit: flag whether header split is enabled
  * @xdp: flag indicating whether XDP is enabled
+ * @no_napi: the queue is not a data queue and does not have NAPI
  * @buf_len: HW-writeable length per each buffer
  * @nid: ID of the closest NUMA node with memory
  */
@@ -85,12 +86,13 @@ struct libeth_fq {
 	enum libeth_fqe_type	type:2;
 	bool			hsplit:1;
 	bool			xdp:1;
+	bool			no_napi:1;
 
 	u32			buf_len;
 	int			nid;
 };
 
-int libeth_rx_fq_create(struct libeth_fq *fq, struct napi_struct *napi);
+int libeth_rx_fq_create(struct libeth_fq *fq, void *napi_dev);
 void libeth_rx_fq_destroy(struct libeth_fq *fq);
 
 /**
-- 
2.47.1