gve: Remove qpl_cfg struct since qpl_ids map with queues respectively

The qpl_cfg struct was used to make sure that no two different queues
are using QPL with the same qpl_id. We can remove that qpl_cfg struct
since now the qpl_ids map with the queues respectively as follows:
For tx queues: qpl_id = tx_qid
For rx queues: qpl_id = max_tx_queues + rx_qid

And when XDP is used, it will need the user to reduce the tx queues to
be at most half of the max_tx_queues. Then it will use the same number
of tx queues starting from the end of existing tx queues for XDP. So the
XDP queues will not exceed the max_tx_queues range and will not overlap
with the rx queues, where the qpl_ids will not have overlapping too.

Considering of that, we remove the qpl_cfg struct to get the qpl_id
directly based on the queue id. Unless we are erroneously allocating a
rx/tx queue that has already been allocated, we would never allocate
the qpl with the same qpl_id twice. In that case, it should fail much
earlier than the QPL assignment.

Suggested-by: Praveen Kaligineedi <pkaligineedi@google.com>
Signed-off-by: Ziwei Xiao <ziweixiao@google.com>
Reviewed-by: Harshitha Ramamurthy <hramamurthy@google.com>
Reviewed-by: Shailend Chand <shailend@google.com>
Link: https://lore.kernel.org/r/20240417205757.778551-1-ziweixiao@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 2 insertions, 37 deletions

diff --git a/drivers/net/ethernet/google/gve/gve.h b/drivers/net/ethernet/google/gve/gve.h
index e97633b68e25..53b5244dc7bc 100644
--- a/drivers/net/ethernet/google/gve/gve.h
+++ b/drivers/net/ethernet/google/gve/gve.h
@@ -639,7 +639,6 @@ struct gve_ptype_lut {
 
 /* Parameters for allocating queue page lists */
 struct gve_qpls_alloc_cfg {
-	struct gve_qpl_config *qpl_cfg;
 	struct gve_queue_config *tx_cfg;
 	struct gve_queue_config *rx_cfg;
 
@@ -655,9 +654,8 @@ struct gve_qpls_alloc_cfg {
 struct gve_tx_alloc_rings_cfg {
 	struct gve_queue_config *qcfg;
 
-	/* qpls and qpl_cfg must already be allocated */
+	/* qpls must already be allocated */
 	struct gve_queue_page_list *qpls;
-	struct gve_qpl_config *qpl_cfg;
 
 	u16 ring_size;
 	u16 start_idx;
@@ -674,9 +672,8 @@ struct gve_rx_alloc_rings_cfg {
 	struct gve_queue_config *qcfg;
 	struct gve_queue_config *qcfg_tx;
 
-	/* qpls and qpl_cfg must already be allocated */
+	/* qpls must already be allocated */
 	struct gve_queue_page_list *qpls;
-	struct gve_qpl_config *qpl_cfg;
 
 	u16 ring_size;
 	u16 packet_buffer_size;
@@ -732,7 +729,6 @@ struct gve_priv {
 	u16 num_xdp_queues;
 	struct gve_queue_config tx_cfg;
 	struct gve_queue_config rx_cfg;
-	struct gve_qpl_config qpl_cfg; /* map used QPL ids */
 	u32 num_ntfy_blks; /* spilt between TX and RX so must be even */
 
 	struct gve_registers __iomem *reg_bar0; /* see gve_register.h */
@@ -1053,37 +1049,6 @@ static inline u32 gve_get_rx_pages_per_qpl_dqo(u32 rx_desc_cnt)
 	return 2 * rx_desc_cnt;
 }
 
-/* Returns a pointer to the next available tx qpl in the list of qpls */
-static inline
-struct gve_queue_page_list *gve_assign_tx_qpl(struct gve_tx_alloc_rings_cfg *cfg,
-					      int tx_qid)
-{
-	/* QPL already in use */
-	if (test_bit(tx_qid, cfg->qpl_cfg->qpl_id_map))
-		return NULL;
-	set_bit(tx_qid, cfg->qpl_cfg->qpl_id_map);
-	return &cfg->qpls[tx_qid];
-}
-
-/* Returns a pointer to the next available rx qpl in the list of qpls */
-static inline
-struct gve_queue_page_list *gve_assign_rx_qpl(struct gve_rx_alloc_rings_cfg *cfg,
-					      int rx_qid)
-{
-	int id = gve_get_rx_qpl_id(cfg->qcfg_tx, rx_qid);
-	/* QPL already in use */
-	if (test_bit(id, cfg->qpl_cfg->qpl_id_map))
-		return NULL;
-	set_bit(id, cfg->qpl_cfg->qpl_id_map);
-	return &cfg->qpls[id];
-}
-
-/* Unassigns the qpl with the given id */
-static inline void gve_unassign_qpl(struct gve_qpl_config *qpl_cfg, int id)
-{
-	clear_bit(id, qpl_cfg->qpl_id_map);
-}
-
 /* Returns the correct dma direction for tx and rx qpls */
 static inline enum dma_data_direction gve_qpl_dma_dir(struct gve_priv *priv,
 						      int id)