Merge branch 'sh_eth-next'

Laurent Pinchart says:

====================
sh_eth: Fix the race between open and MDIO bus registration

This patch series fixes the race condition that exists in the sh_eth driver
between network device open and MDIO bus registration. The actual fix is in
patch 4/5, with previous patches preparing the driver and patch 5/5 cleaning
up an unrelated issue.

I've based the idea on Sergei's attempt to fix the problem and can successfully
boot the Koelsch board over NFS with this series. I might have missed other
issues though, hence the RFC status.

The patches are based on top of the latest net-next master branch.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 31 insertions, 54 deletions

diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c
index efaca6d5e85b..e4bff181c910 100644
--- a/drivers/net/ethernet/renesas/sh_eth.c
+++ b/drivers/net/ethernet/renesas/sh_eth.c
@@ -873,7 +873,7 @@ static int sh_eth_reset(struct net_device *ndev)
 
 		ret = sh_eth_check_reset(ndev);
 		if (ret)
-			goto out;
+			return ret;
 
 		/* Table Init */
 		sh_eth_write(ndev, 0x0, TDLAR);
@@ -900,7 +900,6 @@ static int sh_eth_reset(struct net_device *ndev)
 			     EDMR);
 	}
 
-out:
 	return ret;
 }
 
@@ -1264,7 +1263,7 @@ static int sh_eth_dev_init(struct net_device *ndev, bool start)
 	/* Soft Reset */
 	ret = sh_eth_reset(ndev);
 	if (ret)
-		goto out;
+		return ret;
 
 	if (mdp->cd->rmiimode)
 		sh_eth_write(ndev, 0x1, RMIIMODE);
@@ -1343,7 +1342,6 @@ static int sh_eth_dev_init(struct net_device *ndev, bool start)
 		netif_start_queue(ndev);
 	}
 
-out:
 	return ret;
 }
 
@@ -2583,37 +2581,30 @@ static void sh_eth_tsu_init(struct sh_eth_private *mdp)
 }
 
 /* MDIO bus release function */
-static int sh_mdio_release(struct net_device *ndev)
+static int sh_mdio_release(struct sh_eth_private *mdp)
 {
-	struct mii_bus *bus = dev_get_drvdata(&ndev->dev);
-
 	/* unregister mdio bus */
-	mdiobus_unregister(bus);
-
-	/* remove mdio bus info from net_device */
-	dev_set_drvdata(&ndev->dev, NULL);
+	mdiobus_unregister(mdp->mii_bus);
 
 	/* free bitbang info */
-	free_mdio_bitbang(bus);
+	free_mdio_bitbang(mdp->mii_bus);
 
 	return 0;
 }
 
 /* MDIO bus init function */
-static int sh_mdio_init(struct net_device *ndev, int id,
+static int sh_mdio_init(struct sh_eth_private *mdp,
 			struct sh_eth_plat_data *pd)
 {
 	int ret, i;
 	struct bb_info *bitbang;
-	struct sh_eth_private *mdp = netdev_priv(ndev);
+	struct platform_device *pdev = mdp->pdev;
+	struct device *dev = &mdp->pdev->dev;
 
 	/* create bit control struct for PHY */
-	bitbang = devm_kzalloc(&ndev->dev, sizeof(struct bb_info),
-			       GFP_KERNEL);
-	if (!bitbang) {
-		ret = -ENOMEM;
-		goto out;
-	}
+	bitbang = devm_kzalloc(dev, sizeof(struct bb_info), GFP_KERNEL);
+	if (!bitbang)
+		return -ENOMEM;
 
 	/* bitbang init */
 	bitbang->addr = mdp->addr + mdp->reg_offset[PIR];
@@ -2626,30 +2617,26 @@ static int sh_mdio_init(struct net_device *ndev, int id,
 
 	/* MII controller setting */
 	mdp->mii_bus = alloc_mdio_bitbang(&bitbang->ctrl);
-	if (!mdp->mii_bus) {
-		ret = -ENOMEM;
-		goto out;
-	}
+	if (!mdp->mii_bus)
+		return -ENOMEM;
 
 	/* Hook up MII support for ethtool */
 	mdp->mii_bus->name = "sh_mii";
-	mdp->mii_bus->parent = &ndev->dev;
+	mdp->mii_bus->parent = dev;
 	snprintf(mdp->mii_bus->id, MII_BUS_ID_SIZE, "%s-%x",
-		 mdp->pdev->name, id);
+		 pdev->name, pdev->id);
 
 	/* PHY IRQ */
-	mdp->mii_bus->irq = devm_kzalloc(&ndev->dev,
-					 sizeof(int) * PHY_MAX_ADDR,
+	mdp->mii_bus->irq = devm_kzalloc(dev, sizeof(int) * PHY_MAX_ADDR,
 					 GFP_KERNEL);
 	if (!mdp->mii_bus->irq) {
 		ret = -ENOMEM;
 		goto out_free_bus;
 	}
 
-	/* register mdio bus */
-	if (ndev->dev.parent->of_node) {
-		ret = of_mdiobus_register(mdp->mii_bus,
-					  ndev->dev.parent->of_node);
+	/* register MDIO bus */
+	if (dev->of_node) {
+		ret = of_mdiobus_register(mdp->mii_bus, dev->of_node);
 	} else {
 		for (i = 0; i < PHY_MAX_ADDR; i++)
 			mdp->mii_bus->irq[i] = PHY_POLL;
@@ -2662,14 +2649,10 @@ static int sh_mdio_init(struct net_device *ndev, int id,
 	if (ret)
 		goto out_free_bus;
 
-	dev_set_drvdata(&ndev->dev, mdp->mii_bus);
-
 	return 0;
 
 out_free_bus:
 	free_mdio_bitbang(mdp->mii_bus);
-
-out:
 	return ret;
 }
 
@@ -2782,15 +2765,12 @@ static int sh_eth_drv_probe(struct platform_device *pdev)
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (unlikely(res == NULL)) {
 		dev_err(&pdev->dev, "invalid resource\n");
-		ret = -EINVAL;
-		goto out;
+		return -EINVAL;
 	}
 
 	ndev = alloc_etherdev(sizeof(struct sh_eth_private));
-	if (!ndev) {
-		ret = -ENOMEM;
-		goto out;
-	}
+	if (!ndev)
+		return -ENOMEM;
 
 	/* The sh Ether-specific entries in the device structure. */
 	ndev->base_addr = res->start;
@@ -2900,6 +2880,13 @@ static int sh_eth_drv_probe(struct platform_device *pdev)
 		}
 	}
 
+	/* MDIO bus init */
+	ret = sh_mdio_init(mdp, pd);
+	if (ret) {
+		dev_err(&ndev->dev, "failed to initialise MDIO\n");
+		goto out_release;
+	}
+
 	netif_napi_add(ndev, &mdp->napi, sh_eth_poll, 64);
 
 	/* network device register */
@@ -2907,13 +2894,6 @@ static int sh_eth_drv_probe(struct platform_device *pdev)
 	if (ret)
 		goto out_napi_del;
 
-	/* mdio bus init */
-	ret = sh_mdio_init(ndev, pdev->id, pd);
-	if (ret) {
-		dev_err(&ndev->dev, "failed to initialise MDIO\n");
-		goto out_unregister;
-	}
-
 	/* print device information */
 	netdev_info(ndev, "Base address at 0x%x, %pM, IRQ %d.\n",
 		    (u32)ndev->base_addr, ndev->dev_addr, ndev->irq);
@@ -2922,18 +2902,15 @@ static int sh_eth_drv_probe(struct platform_device *pdev)
 
 	return ret;
 
-out_unregister:
-	unregister_netdev(ndev);
-
 out_napi_del:
 	netif_napi_del(&mdp->napi);
+	sh_mdio_release(mdp);
 
 out_release:
 	/* net_dev free */
 	if (ndev)
 		free_netdev(ndev);
 
-out:
 	return ret;
 }
 
@@ -2942,9 +2919,9 @@ static int sh_eth_drv_remove(struct platform_device *pdev)
 	struct net_device *ndev = platform_get_drvdata(pdev);
 	struct sh_eth_private *mdp = netdev_priv(ndev);
 
-	sh_mdio_release(ndev);
 	unregister_netdev(ndev);
 	netif_napi_del(&mdp->napi);
+	sh_mdio_release(mdp);
 	pm_runtime_disable(&pdev->dev);
 	free_netdev(ndev);