ionic: convert Rx queue buffers to use page_pool

Our home-grown buffer management needs to go away and we need
to be playing nicely with the page_pool infrastructure.  This
converts the Rx traffic queues to use page_pool.

Also, since ionic_rx_buf_size() was removed, redefine
IONIC_PAGE_SIZE to account for IONIC_MAX_BUF_LEN being the
largest allowed buffer to prevent overflowing u16 variables,
which could happen when PAGE_SIZE is defined as >= 64KB.

include/linux/minmax.h:93:37: warning: conversion from 'long unsigned int' to 'u16' {aka 'short unsigned int'} changes value from '65536' to '0' [-Woverflow]
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Link: https://patch.msgid.link/20240906232623.39651-7-brett.creeley@amd.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/pensando/Kconfig

@@ -23,6 +23,7 @@ config IONIC
 	depends on PTP_1588_CLOCK_OPTIONAL
 	select NET_DEVLINK
 	select DIMLIB
+	select PAGE_POOL
 	help
 	  This enables the support for the Pensando family of Ethernet
 	  adapters.  More specific information on this driver can be

drivers/net/ethernet/pensando/ionic/ionic_dev.h

@@ -181,10 +181,7 @@ struct ionic_queue;
 struct ionic_qcq;
 
 #define IONIC_MAX_BUF_LEN			((u16)-1)
-#define IONIC_PAGE_SIZE				PAGE_SIZE
-#define IONIC_PAGE_SPLIT_SZ			(PAGE_SIZE / 2)
-#define IONIC_PAGE_GFP_MASK			(GFP_ATOMIC | __GFP_NOWARN |\
-						 __GFP_COMP | __GFP_MEMALLOC)
+#define IONIC_PAGE_SIZE				MIN(PAGE_SIZE, IONIC_MAX_BUF_LEN)
 
 #define IONIC_XDP_MAX_LINEAR_MTU	(IONIC_PAGE_SIZE -	\
 					 (VLAN_ETH_HLEN +	\
@@ -248,11 +245,6 @@ struct ionic_queue {
 		struct ionic_rxq_desc *rxq;
 		struct ionic_admin_cmd *adminq;
 	};
-	union {
-		void __iomem *cmb_base;
-		struct ionic_txq_desc __iomem *cmb_txq;
-		struct ionic_rxq_desc __iomem *cmb_rxq;
-	};
 	union {
 		void *sg_base;
 		struct ionic_txq_sg_desc *txq_sgl;
@@ -261,8 +253,14 @@ struct ionic_queue {
 	};
 	struct xdp_rxq_info *xdp_rxq_info;
 	struct bpf_prog *xdp_prog;
+	struct page_pool *page_pool;
 	struct ionic_queue *partner;
 
+	union {
+		void __iomem *cmb_base;
+		struct ionic_txq_desc __iomem *cmb_txq;
+		struct ionic_rxq_desc __iomem *cmb_rxq;
+	};
 	unsigned int type;
 	unsigned int hw_index;
 	dma_addr_t base_pa;

drivers/net/ethernet/pensando/ionic/ionic_lif.c

@@ -13,6 +13,7 @@
 #include <linux/cpumask.h>
 #include <linux/crash_dump.h>
 #include <linux/vmalloc.h>
+#include <net/page_pool/helpers.h>
 
 #include "ionic.h"
 #include "ionic_bus.h"
@@ -439,6 +440,9 @@ static void ionic_qcq_free(struct ionic_lif *lif, struct ionic_qcq *qcq)
 		qcq->sg_base_pa = 0;
 	}
 
+	page_pool_destroy(qcq->q.page_pool);
+	qcq->q.page_pool = NULL;
+
 	ionic_qcq_intr_free(lif, qcq);
 	vfree(qcq->q.info);
 	qcq->q.info = NULL;
@@ -553,7 +557,8 @@ static int ionic_qcq_alloc(struct ionic_lif *lif, unsigned int type,
 			   unsigned int cq_desc_size,
 			   unsigned int sg_desc_size,
 			   unsigned int desc_info_size,
-			   unsigned int pid, struct ionic_qcq **qcq)
+			   unsigned int pid, struct bpf_prog *xdp_prog,
+			   struct ionic_qcq **qcq)
 {
 	struct ionic_dev *idev = &lif->ionic->idev;
 	struct device *dev = lif->ionic->dev;
@@ -579,6 +584,31 @@ static int ionic_qcq_alloc(struct ionic_lif *lif, unsigned int type,
 		goto err_out_free_qcq;
 	}
 
+	if (type == IONIC_QTYPE_RXQ) {
+		struct page_pool_params pp_params = {
+			.flags = PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV,
+			.order = 0,
+			.pool_size = num_descs,
+			.nid = NUMA_NO_NODE,
+			.dev = lif->ionic->dev,
+			.napi = &new->napi,
+			.dma_dir = DMA_FROM_DEVICE,
+			.max_len = PAGE_SIZE,
+			.netdev = lif->netdev,
+		};
+
+		if (xdp_prog)
+			pp_params.dma_dir = DMA_BIDIRECTIONAL;
+
+		new->q.page_pool = page_pool_create(&pp_params);
+		if (IS_ERR(new->q.page_pool)) {
+			netdev_err(lif->netdev, "Cannot create page_pool\n");
+			err = PTR_ERR(new->q.page_pool);
+			new->q.page_pool = NULL;
+			goto err_out_free_q_info;
+		}
+	}
+
 	new->q.type = type;
 	new->q.max_sg_elems = lif->qtype_info[type].max_sg_elems;
 
@@ -586,12 +616,12 @@ static int ionic_qcq_alloc(struct ionic_lif *lif, unsigned int type,
 			   desc_size, sg_desc_size, pid);
 	if (err) {
 		netdev_err(lif->netdev, "Cannot initialize queue\n");
-		goto err_out_free_q_info;
+		goto err_out_free_page_pool;
 	}
 
 	err = ionic_alloc_qcq_interrupt(lif, new);
 	if (err)
-		goto err_out_free_q_info;
+		goto err_out_free_page_pool;
 
 	err = ionic_cq_init(lif, &new->cq, &new->intr, num_descs, cq_desc_size);
 	if (err) {
@@ -712,6 +742,8 @@ static int ionic_qcq_alloc(struct ionic_lif *lif, unsigned int type,
 		devm_free_irq(dev, new->intr.vector, &new->napi);
 		ionic_intr_free(lif->ionic, new->intr.index);
 	}
+err_out_free_page_pool:
+	page_pool_destroy(new->q.page_pool);
 err_out_free_q_info:
 	vfree(new->q.info);
 err_out_free_qcq:
@@ -734,7 +766,7 @@ static int ionic_qcqs_alloc(struct ionic_lif *lif)
 			      sizeof(struct ionic_admin_comp),
 			      0,
 			      sizeof(struct ionic_admin_desc_info),
-			      lif->kern_pid, &lif->adminqcq);
+			      lif->kern_pid, NULL, &lif->adminqcq);
 	if (err)
 		return err;
 	ionic_debugfs_add_qcq(lif, lif->adminqcq);
@@ -747,7 +779,7 @@ static int ionic_qcqs_alloc(struct ionic_lif *lif)
 				      sizeof(union ionic_notifyq_comp),
 				      0,
 				      sizeof(struct ionic_admin_desc_info),
-				      lif->kern_pid, &lif->notifyqcq);
+				      lif->kern_pid, NULL, &lif->notifyqcq);
 		if (err)
 			goto err_out;
 		ionic_debugfs_add_qcq(lif, lif->notifyqcq);
@@ -965,7 +997,7 @@ int ionic_lif_create_hwstamp_txq(struct ionic_lif *lif)
 	err = ionic_qcq_alloc(lif, IONIC_QTYPE_TXQ, txq_i, "hwstamp_tx", flags,
 			      num_desc, desc_sz, comp_sz, sg_desc_sz,
 			      sizeof(struct ionic_tx_desc_info),
-			      lif->kern_pid, &txq);
+			      lif->kern_pid, NULL, &txq);
 	if (err)
 		goto err_qcq_alloc;
 
@@ -1025,7 +1057,7 @@ int ionic_lif_create_hwstamp_rxq(struct ionic_lif *lif)
 	err = ionic_qcq_alloc(lif, IONIC_QTYPE_RXQ, rxq_i, "hwstamp_rx", flags,
 			      num_desc, desc_sz, comp_sz, sg_desc_sz,
 			      sizeof(struct ionic_rx_desc_info),
-			      lif->kern_pid, &rxq);
+			      lif->kern_pid, NULL, &rxq);
 	if (err)
 		goto err_qcq_alloc;
 
@@ -2051,7 +2083,7 @@ static int ionic_txrx_alloc(struct ionic_lif *lif)
 		err = ionic_qcq_alloc(lif, IONIC_QTYPE_TXQ, i, "tx", flags,
 				      num_desc, desc_sz, comp_sz, sg_desc_sz,
 				      sizeof(struct ionic_tx_desc_info),
-				      lif->kern_pid, &lif->txqcqs[i]);
+				      lif->kern_pid, NULL, &lif->txqcqs[i]);
 		if (err)
 			goto err_out;
 
@@ -2083,7 +2115,8 @@ static int ionic_txrx_alloc(struct ionic_lif *lif)
 		err = ionic_qcq_alloc(lif, IONIC_QTYPE_RXQ, i, "rx", flags,
 				      num_desc, desc_sz, comp_sz, sg_desc_sz,
 				      sizeof(struct ionic_rx_desc_info),
-				      lif->kern_pid, &lif->rxqcqs[i]);
+				      lif->kern_pid, lif->xdp_prog,
+				      &lif->rxqcqs[i]);
 		if (err)
 			goto err_out;
 
@@ -2679,14 +2712,14 @@ static int ionic_register_rxq_info(struct ionic_queue *q, unsigned int napi_id)
 
 	err = xdp_rxq_info_reg(rxq_info, q->lif->netdev, q->index, napi_id);
 	if (err) {
-		dev_err(q->dev, "Queue %d xdp_rxq_info_reg failed, err %d\n",
+		netdev_err(q->lif->netdev, "q%d xdp_rxq_info_reg failed, err %d\n",
 			   q->index, err);
 		goto err_out;
 	}
 
-	err = xdp_rxq_info_reg_mem_model(rxq_info, MEM_TYPE_PAGE_ORDER0, NULL);
+	err = xdp_rxq_info_reg_mem_model(rxq_info, MEM_TYPE_PAGE_POOL, q->page_pool);
 	if (err) {
-		dev_err(q->dev, "Queue %d xdp_rxq_info_reg_mem_model failed, err %d\n",
+		netdev_err(q->lif->netdev, "q%d xdp_rxq_info_reg_mem_model failed, err %d\n",
 			   q->index, err);
 		xdp_rxq_info_unreg(rxq_info);
 		goto err_out;
@@ -2853,7 +2886,16 @@ static int ionic_cmb_reconfig(struct ionic_lif *lif,
 
 static void ionic_swap_queues(struct ionic_qcq *a, struct ionic_qcq *b)
 {
-	/* only swapping the queues, not the napi, flags, or other stuff */
+	/* only swapping the queues and napi, not flags or other stuff */
+	swap(a->napi,         b->napi);
+
+	if (a->q.type == IONIC_QTYPE_RXQ) {
+		swap(a->q.page_pool, b->q.page_pool);
+		a->q.page_pool->p.napi = &a->napi;
+		if (b->q.page_pool)  /* is NULL when increasing queue count */
+			b->q.page_pool->p.napi = &b->napi;
+	}
+
 	swap(a->q.features,   b->q.features);
 	swap(a->q.num_descs,  b->q.num_descs);
 	swap(a->q.desc_size,  b->q.desc_size);
@@ -2943,7 +2985,7 @@ int ionic_reconfigure_queues(struct ionic_lif *lif,
 				err = ionic_qcq_alloc(lif, IONIC_QTYPE_TXQ, i, "tx", flags,
 						      4, desc_sz, comp_sz, sg_desc_sz,
 						      sizeof(struct ionic_tx_desc_info),
-						      lif->kern_pid, &lif->txqcqs[i]);
+						      lif->kern_pid, NULL, &lif->txqcqs[i]);
 				if (err)
 					goto err_out;
 			}
@@ -2952,7 +2994,7 @@ int ionic_reconfigure_queues(struct ionic_lif *lif,
 			err = ionic_qcq_alloc(lif, IONIC_QTYPE_TXQ, i, "tx", flags,
 					      num_desc, desc_sz, comp_sz, sg_desc_sz,
 					      sizeof(struct ionic_tx_desc_info),
-					      lif->kern_pid, &tx_qcqs[i]);
+					      lif->kern_pid, NULL, &tx_qcqs[i]);
 			if (err)
 				goto err_out;
 		}
@@ -2974,7 +3016,7 @@ int ionic_reconfigure_queues(struct ionic_lif *lif,
 				err = ionic_qcq_alloc(lif, IONIC_QTYPE_RXQ, i, "rx", flags,
 						      4, desc_sz, comp_sz, sg_desc_sz,
 						      sizeof(struct ionic_rx_desc_info),
-						      lif->kern_pid, &lif->rxqcqs[i]);
+						      lif->kern_pid, NULL, &lif->rxqcqs[i]);
 				if (err)
 					goto err_out;
 			}
@@ -2983,7 +3025,7 @@ int ionic_reconfigure_queues(struct ionic_lif *lif,
 			err = ionic_qcq_alloc(lif, IONIC_QTYPE_RXQ, i, "rx", flags,
 					      num_desc, desc_sz, comp_sz, sg_desc_sz,
 					      sizeof(struct ionic_rx_desc_info),
-					      lif->kern_pid, &rx_qcqs[i]);
+					      lif->kern_pid, qparam->xdp_prog, &rx_qcqs[i]);
 			if (err)
 				goto err_out;