From 477f8a6a2c237bedd958ef9fb043f5a73388cd94 Mon Sep 17 00:00:00 2001
From: Michael Chan <michael.chan@broadcom.com>
Date: Mon, 2 Aug 2021 10:52:38 -0400
Subject: [PATCH 21/21] bnxt_en: Don't use static arrays for completion ring
 pages
Git-commit: 03c7448790b87cec82a2f1406ff40dd1a8861170
Patch-mainline: v5.15-rc1
References: git-fixes

We currently store these page addresses and DMA addreses in static
arrays.  On systems with 4K pages, we support up to 64 pages per
completion ring.  The actual number of pages for each completion ring
may be much less than 64.  For example, when the RX ring size is set
to the default 511 entries, only 16 completion ring pages are needed
per ring.

In the next patch, we'll be doubling the maximum number of completion
pages.  So we convert to allocate these arrays as needed instead of
declaring them statically.

Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 65 +++++++++++++++++++++++++++++++
 drivers/net/ethernet/broadcom/bnxt/bnxt.h |  6 +--
 2 files changed, 68 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index ce1ba7b1e90e..b618fd5fe3d2 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -2669,6 +2669,58 @@ static int bnxt_alloc_tx_rings(struct bnxt *bp)
 	return 0;
 }
 
+static void bnxt_free_cp_arrays(struct bnxt_cp_ring_info *cpr)
+{
+	kfree(cpr->cp_desc_ring);
+	cpr->cp_desc_ring = NULL;
+	kfree(cpr->cp_desc_mapping);
+	cpr->cp_desc_mapping = NULL;
+}
+
+static int bnxt_alloc_cp_arrays(struct bnxt_cp_ring_info *cpr, int n)
+{
+	cpr->cp_desc_ring = kcalloc(n, sizeof(*cpr->cp_desc_ring), GFP_KERNEL);
+	if (!cpr->cp_desc_ring)
+		return -ENOMEM;
+	cpr->cp_desc_mapping = kcalloc(n, sizeof(*cpr->cp_desc_mapping),
+				       GFP_KERNEL);
+	if (!cpr->cp_desc_mapping)
+		return -ENOMEM;
+	return 0;
+}
+
+static void bnxt_free_all_cp_arrays(struct bnxt *bp)
+{
+	int i;
+
+	if (!bp->bnapi)
+		return;
+	for (i = 0; i < bp->cp_nr_rings; i++) {
+		struct bnxt_napi *bnapi = bp->bnapi[i];
+
+		if (!bnapi)
+			continue;
+		bnxt_free_cp_arrays(&bnapi->cp_ring);
+	}
+}
+
+static int bnxt_alloc_all_cp_arrays(struct bnxt *bp)
+{
+	int i, n = bp->cp_nr_pages;
+
+	for (i = 0; i < bp->cp_nr_rings; i++) {
+		struct bnxt_napi *bnapi = bp->bnapi[i];
+		int rc;
+
+		if (!bnapi)
+			continue;
+		rc = bnxt_alloc_cp_arrays(&bnapi->cp_ring, n);
+		if (rc)
+			return rc;
+	}
+	return 0;
+}
+
 static void bnxt_free_cp_rings(struct bnxt *bp)
 {
 	int i;
@@ -2696,6 +2748,7 @@ static void bnxt_free_cp_rings(struct bnxt *bp)
 			if (cpr2) {
 				ring = &cpr2->cp_ring_struct;
 				bnxt_free_ring(bp, &ring->ring_mem);
+				bnxt_free_cp_arrays(cpr2);
 				kfree(cpr2);
 				cpr->cp_ring_arr[j] = NULL;
 			}
@@ -2714,6 +2767,12 @@ static struct bnxt_cp_ring_info *bnxt_alloc_cp_sub_ring(struct bnxt *bp)
 	if (!cpr)
 		return NULL;
 
+	rc = bnxt_alloc_cp_arrays(cpr, bp->cp_nr_pages);
+	if (rc) {
+		bnxt_free_cp_arrays(cpr);
+		kfree(cpr);
+		return NULL;
+	}
 	ring = &cpr->cp_ring_struct;
 	rmem = &ring->ring_mem;
 	rmem->nr_pages = bp->cp_nr_pages;
@@ -2724,6 +2783,7 @@ static struct bnxt_cp_ring_info *bnxt_alloc_cp_sub_ring(struct bnxt *bp)
 	rc = bnxt_alloc_ring(bp, rmem);
 	if (rc) {
 		bnxt_free_ring(bp, rmem);
+		bnxt_free_cp_arrays(cpr);
 		kfree(cpr);
 		cpr = NULL;
 	}
@@ -3637,6 +3697,7 @@ static void bnxt_free_mem(struct bnxt *bp, bool irq_re_init)
 	bnxt_free_tx_rings(bp);
 	bnxt_free_rx_rings(bp);
 	bnxt_free_cp_rings(bp);
+	bnxt_free_all_cp_arrays(bp);
 	bnxt_free_ntp_fltrs(bp, irq_re_init);
 	if (irq_re_init) {
 		bnxt_free_ring_stats(bp);
@@ -3753,6 +3814,10 @@ static int bnxt_alloc_mem(struct bnxt *bp, bool irq_re_init)
 			goto alloc_mem_err;
 	}
 
+	rc = bnxt_alloc_all_cp_arrays(bp);
+	if (rc)
+		goto alloc_mem_err;
+
 	bnxt_init_ring_struct(bp);
 
 	rc = bnxt_alloc_rx_rings(bp);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 11591dd557a8..7472947b1230 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -818,11 +818,11 @@ struct bnxt_cp_ring_info {
 	struct dim		dim;
 
 	union {
-		struct tx_cmp	*cp_desc_ring[MAX_CP_PAGES];
-		struct nqe_cn	*nq_desc_ring[MAX_CP_PAGES];
+		struct tx_cmp	**cp_desc_ring;
+		struct nqe_cn	**nq_desc_ring;
 	};
 
-	dma_addr_t		cp_desc_mapping[MAX_CP_PAGES];
+	dma_addr_t		*cp_desc_mapping;
 
 	struct ctx_hw_stats	*hw_stats;
 	dma_addr_t		hw_stats_map;
-- 
2.16.4