[PATCH net] octeontx2-af: fix CGX debugfs RVU AF PCI reference leaks

[Ratheesh Kannoth <rkannoth@marvell.com>]

CGX per-lmac debugfs seq readers obtained struct rvu via
pci_get_drvdata(pci_get_device(..., PCI_DEVID_OCTEONTX2_RVU_AF, ...)),
which leaks a PCI device reference on every read. Store rvu and the CGX
handle in debugfs inode private data when creating stats, mac_filter,
and fwdata files (one context per CGX), and use debugfs aux numbers for
fwdata so lmac_id matches the other CGX debugfs entries.

Fixes: f967488d095e ("octeontx2-af: Add per CGX port level NIX Rx/Tx counters")
Fixes: dbc52debf95f ("octeontx2-af: Debugfs support for DMAC filters")
Fixes: 49f02e6877d1 ("Octeontx2-af: Debugfs support for firmware data")
Cc: Linu Cherian <lcherian@marvell.com>
Reported-by: Yuho Choi <dbgh9129@gmail.com>
Signed-off-by: Ratheesh Kannoth <rkannoth@marvell.com>
---
 .../marvell/octeontx2/af/rvu_debugfs.c        | 77 ++++++++++---------
 1 file changed, 42 insertions(+), 35 deletions(-)

diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
index fa461489acdd..77ff734438cd 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
@@ -2809,6 +2809,14 @@ static void rvu_dbg_npa_init(struct rvu *rvu)
 			    &rvu_dbg_npa_ndc_hits_miss_fops);
 }
 
+/* Per-lmac CGX debugfs files need both RVU and CGX handle; inode->i_private
+ * points here so seq_file ops avoid pci_get_device(PCI_DEVID_OCTEONTX2_RVU_AF).
+ */
+struct rvu_cgx_lmac_dbgfs_ctx {
+	struct rvu	*rvu;
+	void		*cgxd;
+};
+
 #define PRINT_CGX_CUML_NIXRX_STATUS(idx, name)				\
 	({								\
 		u64 cnt;						\
@@ -2831,18 +2839,14 @@ static void rvu_dbg_npa_init(struct rvu *rvu)
 
 static int cgx_print_stats(struct seq_file *s, int lmac_id)
 {
+	struct rvu_cgx_lmac_dbgfs_ctx *dctx = s->private;
 	struct cgx_link_user_info linfo;
 	struct mac_ops *mac_ops;
-	void *cgxd = s->private;
+	void *cgxd = dctx->cgxd;
+	struct rvu *rvu = dctx->rvu;
 	u64 ucast, mcast, bcast;
 	int stat = 0, err = 0;
 	u64 tx_stat, rx_stat;
-	struct rvu *rvu;
-
-	rvu = pci_get_drvdata(pci_get_device(PCI_VENDOR_ID_CAVIUM,
-					     PCI_DEVID_OCTEONTX2_RVU_AF, NULL));
-	if (!rvu)
-		return -ENODEV;
 
 	mac_ops = get_mac_ops(cgxd);
 	/* There can be no CGX devices at all */
@@ -2949,20 +2953,16 @@ RVU_DEBUG_SEQ_FOPS(cgx_stat, cgx_stat_display, NULL);
 
 static int cgx_print_dmac_flt(struct seq_file *s, int lmac_id)
 {
+	struct rvu_cgx_lmac_dbgfs_ctx *dctx = s->private;
 	struct pci_dev *pdev = NULL;
-	void *cgxd = s->private;
+	void *cgxd = dctx->cgxd;
+	struct rvu *rvu = dctx->rvu;
 	char *bcast, *mcast;
 	u16 index, domain;
 	u8 dmac[ETH_ALEN];
-	struct rvu *rvu;
 	u64 cfg, mac;
 	int pf;
 
-	rvu = pci_get_drvdata(pci_get_device(PCI_VENDOR_ID_CAVIUM,
-					     PCI_DEVID_OCTEONTX2_RVU_AF, NULL));
-	if (!rvu)
-		return -ENODEV;
-
 	pf = cgxlmac_to_pf(rvu, cgx_get_cgxid(cgxd), lmac_id);
 	domain = 2;
 
@@ -3009,17 +3009,13 @@ RVU_DEBUG_SEQ_FOPS(cgx_dmac_flt, cgx_dmac_flt_display, NULL);
 
 static int cgx_print_fwdata(struct seq_file *s, int lmac_id)
 {
+	struct rvu_cgx_lmac_dbgfs_ctx *dctx = s->private;
 	struct cgx_lmac_fwdata_s *fwdata;
-	void *cgxd = s->private;
+	void *cgxd = dctx->cgxd;
+	struct rvu *rvu = dctx->rvu;
 	struct phy_s *phy;
-	struct rvu *rvu;
 	int cgx_id, i;
 
-	rvu = pci_get_drvdata(pci_get_device(PCI_VENDOR_ID_CAVIUM,
-					     PCI_DEVID_OCTEONTX2_RVU_AF, NULL));
-	if (!rvu)
-		return -ENODEV;
-
 	if (!rvu->fwdata)
 		return -EAGAIN;
 
@@ -3126,20 +3122,31 @@ static void rvu_dbg_cgx_init(struct rvu *rvu)
 		rvu->rvu_dbg.cgx = debugfs_create_dir(dname,
 						      rvu->rvu_dbg.cgx_root);
 
-		for_each_set_bit(lmac_id, &lmac_bmap, rvu->hw->lmac_per_cgx) {
-			/* lmac debugfs dir */
-			sprintf(dname, "lmac%d", lmac_id);
-			rvu->rvu_dbg.lmac =
-				debugfs_create_dir(dname, rvu->rvu_dbg.cgx);
-
-			debugfs_create_file_aux_num("stats", 0600, rvu->rvu_dbg.lmac,
-					    cgx, lmac_id, &rvu_dbg_cgx_stat_fops);
-			debugfs_create_file_aux_num("mac_filter", 0600,
-					    rvu->rvu_dbg.lmac, cgx, lmac_id,
-					    &rvu_dbg_cgx_dmac_flt_fops);
-			debugfs_create_file("fwdata", 0600,
-					    rvu->rvu_dbg.lmac, cgx,
-					    &rvu_dbg_cgx_fwdata_fops);
+		{
+			struct rvu_cgx_lmac_dbgfs_ctx *ctx;
+
+			ctx = devm_kzalloc(rvu->dev, sizeof(*ctx), GFP_KERNEL);
+			if (!ctx)
+				continue;
+
+			ctx->rvu = rvu;
+			ctx->cgxd = cgx;
+
+			for_each_set_bit(lmac_id, &lmac_bmap, rvu->hw->lmac_per_cgx) {
+				/* lmac debugfs dir */
+				sprintf(dname, "lmac%d", lmac_id);
+				rvu->rvu_dbg.lmac =
+					debugfs_create_dir(dname, rvu->rvu_dbg.cgx);
+
+				debugfs_create_file_aux_num("stats", 0600, rvu->rvu_dbg.lmac,
+							    ctx, lmac_id, &rvu_dbg_cgx_stat_fops);
+				debugfs_create_file_aux_num("mac_filter", 0600,
+							    rvu->rvu_dbg.lmac, ctx, lmac_id,
+							    &rvu_dbg_cgx_dmac_flt_fops);
+				debugfs_create_file_aux_num("fwdata", 0600,
+							    rvu->rvu_dbg.lmac, ctx,
+							    lmac_id, &rvu_dbg_cgx_fwdata_fops);
+			}
 		}
 	}
 }
-- 
2.43.0