ionic: reduce contiguous memory allocation requirement

Split out the queue descriptor blocks into separate dma
allocations to make for smaller blocks.
Co-developed-by: Neel Patel <neel@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -112,7 +112,8 @@ static const struct debugfs_reg32 intr_ctrl_regs[] = {
 
 void ionic_debugfs_add_qcq(struct ionic_lif *lif, struct ionic_qcq *qcq)
 {
-	struct dentry *q_dentry, *cq_dentry, *intr_dentry, *stats_dentry;
+	struct dentry *qcq_dentry, *q_dentry, *cq_dentry;
+	struct dentry *intr_dentry, *stats_dentry;
 	struct ionic_dev *idev = &lif->ionic->idev;
 	struct debugfs_regset32 *intr_ctrl_regset;
 	struct ionic_intr_info *intr = &qcq->intr;
@@ -121,21 +122,21 @@ void ionic_debugfs_add_qcq(struct ionic_lif *lif, struct ionic_qcq *qcq)
 	struct ionic_queue *q = &qcq->q;
 	struct ionic_cq *cq = &qcq->cq;
 
-	qcq->dentry = debugfs_create_dir(q->name, lif->dentry);
+	qcq_dentry = debugfs_create_dir(q->name, lif->dentry);
+	if (IS_ERR_OR_NULL(qcq_dentry))
+		return;
+	qcq->dentry = qcq_dentry;
 
-	debugfs_create_x32("total_size", 0400, qcq->dentry, &qcq->total_size);
-	debugfs_create_x64("base_pa", 0400, qcq->dentry, &qcq->base_pa);
+	debugfs_create_x64("q_base_pa", 0400, qcq_dentry, &qcq->q_base_pa);
+	debugfs_create_x32("q_size", 0400, qcq_dentry, &qcq->q_size);
+	debugfs_create_x64("cq_base_pa", 0400, qcq_dentry, &qcq->cq_base_pa);
+	debugfs_create_x32("cq_size", 0400, qcq_dentry, &qcq->cq_size);
+	debugfs_create_x64("sg_base_pa", 0400, qcq_dentry, &qcq->sg_base_pa);
+	debugfs_create_x32("sg_size", 0400, qcq_dentry, &qcq->sg_size);
 
 	q_dentry = debugfs_create_dir("q", qcq->dentry);
 
 	debugfs_create_u32("index", 0400, q_dentry, &q->index);
-	debugfs_create_x64("base_pa", 0400, q_dentry, &q->base_pa);
-	if (qcq->flags & IONIC_QCQ_F_SG) {
-		debugfs_create_x64("sg_base_pa", 0400, q_dentry,
-				   &q->sg_base_pa);
-		debugfs_create_u32("sg_desc_size", 0400, q_dentry,
-				   &q->sg_desc_size);
-	}
 	debugfs_create_u32("num_descs", 0400, q_dentry, &q->num_descs);
 	debugfs_create_u32("desc_size", 0400, q_dentry, &q->desc_size);
 	debugfs_create_u32("pid", 0400, q_dentry, &q->pid);

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

@@ -306,9 +306,23 @@ static void ionic_qcq_free(struct ionic_lif *lif, struct ionic_qcq *qcq)
 
 	ionic_debugfs_del_qcq(qcq);
 
-	dma_free_coherent(dev, qcq->total_size, qcq->base, qcq->base_pa);
-	qcq->base = NULL;
-	qcq->base_pa = 0;
+	if (qcq->q_base) {
+		dma_free_coherent(dev, qcq->q_size, qcq->q_base, qcq->q_base_pa);
+		qcq->q_base = NULL;
+		qcq->q_base_pa = 0;
+	}
+
+	if (qcq->cq_base) {
+		dma_free_coherent(dev, qcq->cq_size, qcq->cq_base, qcq->cq_base_pa);
+		qcq->cq_base = NULL;
+		qcq->cq_base_pa = 0;
+	}
+
+	if (qcq->sg_base) {
+		dma_free_coherent(dev, qcq->sg_size, qcq->sg_base, qcq->sg_base_pa);
+		qcq->sg_base = NULL;
+		qcq->sg_base_pa = 0;
+	}
 
 	if (qcq->flags & IONIC_QCQ_F_INTR) {
 		irq_set_affinity_hint(qcq->intr.vector, NULL);
@@ -374,7 +388,6 @@ static int ionic_qcq_alloc(struct ionic_lif *lif, unsigned int type,
 			   unsigned int pid, struct ionic_qcq **qcq)
 {
 	struct ionic_dev *idev = &lif->ionic->idev;
-	u32 q_size, cq_size, sg_size, total_size;
 	struct device *dev = lif->ionic->dev;
 	void *q_base, *cq_base, *sg_base;
 	dma_addr_t cq_base_pa = 0;
@@ -385,21 +398,6 @@ static int ionic_qcq_alloc(struct ionic_lif *lif, unsigned int type,
 
 	*qcq = NULL;
 
-	q_size  = num_descs * desc_size;
-	cq_size = num_descs * cq_desc_size;
-	sg_size = num_descs * sg_desc_size;
-
-	total_size = ALIGN(q_size, PAGE_SIZE) + ALIGN(cq_size, PAGE_SIZE);
-	/* Note: aligning q_size/cq_size is not enough due to cq_base
-	 * address aligning as q_base could be not aligned to the page.
-	 * Adding PAGE_SIZE.
-	 */
-	total_size += PAGE_SIZE;
-	if (flags & IONIC_QCQ_F_SG) {
-		total_size += ALIGN(sg_size, PAGE_SIZE);
-		total_size += PAGE_SIZE;
-	}
-
 	new = devm_kzalloc(dev, sizeof(*new), GFP_KERNEL);
 	if (!new) {
 		netdev_err(lif->netdev, "Cannot allocate queue structure\n");
@@ -414,7 +412,7 @@ static int ionic_qcq_alloc(struct ionic_lif *lif, unsigned int type,
 	if (!new->q.info) {
 		netdev_err(lif->netdev, "Cannot allocate queue info\n");
 		err = -ENOMEM;
-		goto err_out;
+		goto err_out_free_qcq;
 	}
 
 	new->q.type = type;
@@ -423,7 +421,7 @@ 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;
+		goto err_out_free_q_info;
 	}
 
 	if (flags & IONIC_QCQ_F_INTR) {
@@ -471,46 +469,68 @@ static int ionic_qcq_alloc(struct ionic_lif *lif, unsigned int type,
 	err = ionic_cq_init(lif, &new->cq, &new->intr, num_descs, cq_desc_size);
 	if (err) {
 		netdev_err(lif->netdev, "Cannot initialize completion queue\n");
-		goto err_out_free_irq;
+		goto err_out_free_cq_info;
 	}
 
-	new->base = dma_alloc_coherent(dev, total_size, &new->base_pa,
+	new->q_size = PAGE_SIZE + (num_descs * desc_size);
+	new->q_base = dma_alloc_coherent(dev, new->q_size, &new->q_base_pa,
 					 GFP_KERNEL);
-	if (!new->base) {
+	if (!new->q_base) {
 		netdev_err(lif->netdev, "Cannot allocate queue DMA memory\n");
 		err = -ENOMEM;
-		goto err_out_free_irq;
+		goto err_out_free_cq_info;
 	}
+	q_base = PTR_ALIGN(new->q_base, PAGE_SIZE);
+	q_base_pa = ALIGN(new->q_base_pa, PAGE_SIZE);
+	ionic_q_map(&new->q, q_base, q_base_pa);
 
-	new->total_size = total_size;
-
-	q_base = new->base;
-	q_base_pa = new->base_pa;
-
-	cq_base = (void *)ALIGN((uintptr_t)q_base + q_size, PAGE_SIZE);
-	cq_base_pa = ALIGN(q_base_pa + q_size, PAGE_SIZE);
+	new->cq_size = PAGE_SIZE + (num_descs * cq_desc_size);
+	new->cq_base = dma_alloc_coherent(dev, new->cq_size, &new->cq_base_pa,
+					  GFP_KERNEL);
+	if (!new->cq_base) {
+		netdev_err(lif->netdev, "Cannot allocate cq DMA memory\n");
+		err = -ENOMEM;
+		goto err_out_free_q;
+	}
+	cq_base = PTR_ALIGN(new->cq_base, PAGE_SIZE);
+	cq_base_pa = ALIGN(new->cq_base_pa, PAGE_SIZE);
+	ionic_cq_map(&new->cq, cq_base, cq_base_pa);
+	ionic_cq_bind(&new->cq, &new->q);
 
 	if (flags & IONIC_QCQ_F_SG) {
-		sg_base = (void *)ALIGN((uintptr_t)cq_base + cq_size,
-					PAGE_SIZE);
-		sg_base_pa = ALIGN(cq_base_pa + cq_size, PAGE_SIZE);
+		new->sg_size = PAGE_SIZE + (num_descs * sg_desc_size);
+		new->sg_base = dma_alloc_coherent(dev, new->sg_size, &new->sg_base_pa,
+						  GFP_KERNEL);
+		if (!new->sg_base) {
+			netdev_err(lif->netdev, "Cannot allocate sg DMA memory\n");
+			err = -ENOMEM;
+			goto err_out_free_cq;
+		}
+		sg_base = PTR_ALIGN(new->sg_base, PAGE_SIZE);
+		sg_base_pa = ALIGN(new->sg_base_pa, PAGE_SIZE);
 		ionic_q_sg_map(&new->q, sg_base, sg_base_pa);
 	}
 
-	ionic_q_map(&new->q, q_base, q_base_pa);
-	ionic_cq_map(&new->cq, cq_base, cq_base_pa);
-	ionic_cq_bind(&new->cq, &new->q);
-
 	*qcq = new;
 
 	return 0;
 
+err_out_free_cq:
+	dma_free_coherent(dev, new->cq_size, new->cq_base, new->cq_base_pa);
+err_out_free_q:
+	dma_free_coherent(dev, new->q_size, new->q_base, new->q_base_pa);
+err_out_free_cq_info:
+	devm_kfree(dev, new->cq.info);
 err_out_free_irq:
 	if (flags & IONIC_QCQ_F_INTR)
 		devm_free_irq(dev, new->intr.vector, &new->napi);
 err_out_free_intr:
 	if (flags & IONIC_QCQ_F_INTR)
 		ionic_intr_free(lif->ionic, new->intr.index);
+err_out_free_q_info:
+	devm_kfree(dev, new->q.info);
+err_out_free_qcq:
+	devm_kfree(dev, new);
 err_out:
 	dev_err(dev, "qcq alloc of %s%d failed %d\n", name, index, err);
 	return err;

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

@@ -57,9 +57,15 @@ struct ionic_napi_stats {
 };
 
 struct ionic_qcq {
-	void *base;
-	dma_addr_t base_pa;
-	unsigned int total_size;
+	void *q_base;
+	dma_addr_t q_base_pa;
+	u32 q_size;
+	void *cq_base;
+	dma_addr_t cq_base_pa;
+	u32 cq_size;
+	void *sg_base;
+	dma_addr_t sg_base_pa;
+	u32 sg_size;
 	struct ionic_queue q;
 	struct ionic_cq cq;
 	struct ionic_intr_info intr;