gve: adminq: DQO specific device descriptor logic

- In addition to TX and RX queues, DQO has TX completion and RX buffer
  queues.
  - TX completions are received when the device has completed sending a
    packet on the wire.
  - RX buffers are posted on a separate queue form the RX completions.
- DQO descriptor rings are allowed to be smaller than PAGE_SIZE.

Signed-off-by: Bailey Forrest <bcf@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Catherine Sullivan <csully@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/google/gve/gve.h b/drivers/net/ethernet/google/gve/gve.h
index 9cb9b8f..9045b86 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve.h
+++ b/drivers/net/ethernet/google/gve/gve.h
@@ -194,6 +194,11 @@ struct gve_qpl_config {
        unsigned long *qpl_id_map; /* bitmap of used qpl ids */
 };
 
+struct gve_options_dqo_rda {
+       u16 tx_comp_ring_entries; /* number of tx_comp descriptors */
+       u16 rx_buff_ring_entries; /* number of rx_buff descriptors */
+};
+
 /* GVE_QUEUE_FORMAT_UNSPECIFIED must be zero since 0 is the default value
  * when the entire configure_device_resources command is zeroed out and the
  * queue_format is not specified.
@@ -286,6 +291,8 @@ struct gve_priv {
        /* Gvnic device link speed from hypervisor. */
        u64 link_speed;
 
+       struct gve_options_dqo_rda options_dqo_rda;
+
        enum gve_queue_format queue_format;
 };
 
@@ -533,6 +540,12 @@ static inline enum dma_data_direction gve_qpl_dma_dir(struct gve_priv *priv,
                return DMA_FROM_DEVICE;
 }
 
+static inline bool gve_is_gqi(struct gve_priv *priv)
+{
+       return priv->queue_format == GVE_GQI_RDA_FORMAT ||
+               priv->queue_format == GVE_GQI_QPL_FORMAT;
+}
+
 /* buffers */
 int gve_alloc_page(struct gve_priv *priv, struct device *dev,
                   struct page **page, dma_addr_t *dma,

diff --git a/drivers/net/ethernet/google/gve/gve_adminq.c b/drivers/net/ethernet/google/gve/gve_adminq.c
index 9dfce9a..9efa60c 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve_adminq.c
+++ b/drivers/net/ethernet/google/gve/gve_adminq.c
@@ -602,6 +602,40 @@ int gve_adminq_destroy_rx_queues(struct gve_priv *priv, u32 num_queues)
        return gve_adminq_kick_and_wait(priv);
 }
 
+static int gve_set_desc_cnt(struct gve_priv *priv,
+                           struct gve_device_descriptor *descriptor)
+{
+       priv->tx_desc_cnt = be16_to_cpu(descriptor->tx_queue_entries);
+       if (priv->tx_desc_cnt * sizeof(priv->tx->desc[0]) < PAGE_SIZE) {
+               dev_err(&priv->pdev->dev, "Tx desc count %d too low\n",
+                       priv->tx_desc_cnt);
+               return -EINVAL;
+       }
+       priv->rx_desc_cnt = be16_to_cpu(descriptor->rx_queue_entries);
+       if (priv->rx_desc_cnt * sizeof(priv->rx->desc.desc_ring[0])
+           < PAGE_SIZE) {
+               dev_err(&priv->pdev->dev, "Rx desc count %d too low\n",
+                       priv->rx_desc_cnt);
+               return -EINVAL;
+       }
+       return 0;
+}
+
+static int
+gve_set_desc_cnt_dqo(struct gve_priv *priv,
+                    const struct gve_device_descriptor *descriptor,
+                    const struct gve_device_option_dqo_rda *dev_op_dqo_rda)
+{
+       priv->tx_desc_cnt = be16_to_cpu(descriptor->tx_queue_entries);
+       priv->options_dqo_rda.tx_comp_ring_entries =
+               be16_to_cpu(dev_op_dqo_rda->tx_comp_ring_entries);
+       priv->rx_desc_cnt = be16_to_cpu(descriptor->rx_queue_entries);
+       priv->options_dqo_rda.rx_buff_ring_entries =
+               be16_to_cpu(dev_op_dqo_rda->rx_buff_ring_entries);
+
+       return 0;
+}
+
 int gve_adminq_describe_device(struct gve_priv *priv)
 {
        struct gve_device_option_gqi_rda *dev_op_gqi_rda = NULL;
@@ -655,22 +689,14 @@ int gve_adminq_describe_device(struct gve_priv *priv)
                dev_info(&priv->pdev->dev,
                         "Driver is running with GQI QPL queue format.\n");
        }
-
-       priv->tx_desc_cnt = be16_to_cpu(descriptor->tx_queue_entries);
-       if (priv->tx_desc_cnt * sizeof(priv->tx->desc[0]) < PAGE_SIZE) {
-               dev_err(&priv->pdev->dev, "Tx desc count %d too low\n", priv->tx_desc_cnt);
-               err = -EINVAL;
-               goto free_device_descriptor;
+       if (gve_is_gqi(priv)) {
+               err = gve_set_desc_cnt(priv, descriptor);
+       } else {
+               err = gve_set_desc_cnt_dqo(priv, descriptor, dev_op_dqo_rda);
        }
-       priv->rx_desc_cnt = be16_to_cpu(descriptor->rx_queue_entries);
-       if (priv->rx_desc_cnt * sizeof(priv->rx->desc.desc_ring[0])
-           < PAGE_SIZE ||
-           priv->rx_desc_cnt * sizeof(priv->rx->data.data_ring[0])
-           < PAGE_SIZE) {
-               dev_err(&priv->pdev->dev, "Rx desc count %d too low\n", priv->rx_desc_cnt);
-               err = -EINVAL;
+       if (err)
                goto free_device_descriptor;
-       }
+
        priv->max_registered_pages =
                                be64_to_cpu(descriptor->max_registered_pages);
        mtu = be16_to_cpu(descriptor->mtu);
@@ -686,7 +712,8 @@ int gve_adminq_describe_device(struct gve_priv *priv)
        dev_info(&priv->pdev->dev, "MAC addr: %pM\n", mac);
        priv->tx_pages_per_qpl = be16_to_cpu(descriptor->tx_pages_per_qpl);
        priv->rx_data_slot_cnt = be16_to_cpu(descriptor->rx_pages_per_qpl);
-       if (priv->rx_data_slot_cnt < priv->rx_desc_cnt) {
+
+       if (gve_is_gqi(priv) && priv->rx_data_slot_cnt < priv->rx_desc_cnt) {
                dev_err(&priv->pdev->dev, "rx_data_slot_cnt cannot be smaller than rx_desc_cnt, setting rx_desc_cnt down to %d.\n",
                        priv->rx_data_slot_cnt);
                priv->rx_desc_cnt = priv->rx_data_slot_cnt;