Merge branch 'devlink-make-ethtool-compat-reliable'

Jakub Kicinski says:

====================
devlink: make ethtool compat reliable

This is a follow up to the series which added device flash
updates via devlink. I went with the approach of adding a
new NDO in the end. It seems to end up looking cleaner.

First patch removes the option to build devlink as a module.
Users can still decide to not build it, but the module option
ends up not being worth the maintenance cost.

Next two patches add a NDO which can be used to ask the driver
to return a devlink instance associated with a given netdev,
instead of iterating over devlink ports. Drivers which implement
this NDO must take into account the potential impact on the
visibility of the devlink instance.

With the new NDO in place we can remove NFP ethtool flash update
code.

Fifth patch makes sure we hold a reference to dev while
callbacks are active.

Last but not least the NULL-check of devlink->ops is moved
to instance allocation time.

Last but not least missing checks for devlink->ops are added.
There is currently no driver registering devlink without ops,
so can just fix this in -next.

v2 (Michal): add netdev_to_devlink() in patch 3.
v3 (Florian):
 - add missing checks for devlink->ops;
 - move locking/holding into devlink_compat_ functions.
v4 (Jiri):
 - hold devlink_mutex around callbacks (patch 2);
 - require non-NULL ops (patch 6).
====================

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

14 files changed, 15 insertions, 33 deletions

diff --git a/drivers/infiniband/hw/bnxt_re/Kconfig b/drivers/infiniband/hw/bnxt_re/Kconfig
index 18f5ed082f41..19982a4a9bba 100644
--- a/drivers/infiniband/hw/bnxt_re/Kconfig
+++ b/drivers/infiniband/hw/bnxt_re/Kconfig
@@ -1,7 +1,6 @@
 config INFINIBAND_BNXT_RE
     tristate "Broadcom Netxtreme HCA support"
     depends on ETHERNET && NETDEVICES && PCI && INET && DCB
-    depends on MAY_USE_DEVLINK
     select NET_VENDOR_BROADCOM
     select BNXT
     ---help---
diff --git a/drivers/infiniband/hw/mlx4/Kconfig b/drivers/infiniband/hw/mlx4/Kconfig
index d1de3285fd88..4e9936731867 100644
--- a/drivers/infiniband/hw/mlx4/Kconfig
+++ b/drivers/infiniband/hw/mlx4/Kconfig
@@ -2,7 +2,6 @@ config MLX4_INFINIBAND
 	tristate "Mellanox ConnectX HCA support"
 	depends on NETDEVICES && ETHERNET && PCI && INET
 	depends on INFINIBAND_USER_ACCESS || !INFINIBAND_USER_ACCESS
-	depends on MAY_USE_DEVLINK
 	select NET_VENDOR_MELLANOX
 	select MLX4_CORE
 	---help---
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 6210757772ed..5e4ca082cfcd 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -505,7 +505,6 @@ source "drivers/net/hyperv/Kconfig"
 config NETDEVSIM
 	tristate "Simulated networking device"
 	depends on DEBUG_FS
-	depends on MAY_USE_DEVLINK
 	help
 	  This driver is a developer testing tool and software model that can
 	  be used to test various control path networking APIs, especially
diff --git a/drivers/net/ethernet/broadcom/Kconfig b/drivers/net/ethernet/broadcom/Kconfig
index c1d3ee9baf7e..716bfbba59cf 100644
--- a/drivers/net/ethernet/broadcom/Kconfig
+++ b/drivers/net/ethernet/broadcom/Kconfig
@@ -194,7 +194,6 @@ config SYSTEMPORT
 config BNXT
 	tristate "Broadcom NetXtreme-C/E support"
 	depends on PCI
-	depends on MAY_USE_DEVLINK
 	select FW_LOADER
 	select LIBCRC32C
 	---help---
diff --git a/drivers/net/ethernet/cavium/Kconfig b/drivers/net/ethernet/cavium/Kconfig
index 05f4a3b21e29..6650e2a5f171 100644
--- a/drivers/net/ethernet/cavium/Kconfig
+++ b/drivers/net/ethernet/cavium/Kconfig
@@ -64,7 +64,6 @@ config CAVIUM_PTP
 config LIQUIDIO
 	tristate "Cavium LiquidIO support"
 	depends on 64BIT && PCI
-	depends on MAY_USE_DEVLINK
 	depends on PCI
 	imply PTP_1588_CLOCK
 	select FW_LOADER
diff --git a/drivers/net/ethernet/mellanox/mlx4/Kconfig b/drivers/net/ethernet/mellanox/mlx4/Kconfig
index f200b8c420d5..ff8057ed97ee 100644
--- a/drivers/net/ethernet/mellanox/mlx4/Kconfig
+++ b/drivers/net/ethernet/mellanox/mlx4/Kconfig
@@ -4,7 +4,6 @@
 
 config MLX4_EN
 	tristate "Mellanox Technologies 1/10/40Gbit Ethernet support"
-	depends on MAY_USE_DEVLINK
 	depends on PCI && NETDEVICES && ETHERNET && INET
 	select MLX4_CORE
 	imply PTP_1588_CLOCK
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
index 37a551436e4a..6debffb8336b 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
+++ b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
@@ -4,7 +4,6 @@
 
 config MLX5_CORE
 	tristate "Mellanox 5th generation network adapters (ConnectX series) core driver"
-	depends on MAY_USE_DEVLINK
 	depends on PCI
 	imply PTP_1588_CLOCK
 	imply VXLAN
diff --git a/drivers/net/ethernet/mellanox/mlxsw/Kconfig b/drivers/net/ethernet/mellanox/mlxsw/Kconfig
index b9a25aed5d11..9c195dfed031 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/Kconfig
+++ b/drivers/net/ethernet/mellanox/mlxsw/Kconfig
@@ -4,7 +4,6 @@
 
 config MLXSW_CORE
 	tristate "Mellanox Technologies Switch ASICs support"
-	depends on MAY_USE_DEVLINK
 	---help---
 	  This driver supports Mellanox Technologies Switch ASICs family.
 
diff --git a/drivers/net/ethernet/netronome/Kconfig b/drivers/net/ethernet/netronome/Kconfig
index 66f15b05b65e..549898d5d450 100644
--- a/drivers/net/ethernet/netronome/Kconfig
+++ b/drivers/net/ethernet/netronome/Kconfig
@@ -19,7 +19,6 @@ config NFP
 	tristate "Netronome(R) NFP4000/NFP6000 NIC driver"
 	depends on PCI && PCI_MSI
 	depends on VXLAN || VXLAN=n
-	depends on MAY_USE_DEVLINK
 	---help---
 	  This driver supports the Netronome(R) NFP4000/NFP6000 based
 	  cards working as a advanced Ethernet NIC.  It works with both
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_app.h b/drivers/net/ethernet/netronome/nfp/nfp_app.h
index d578d856a009..f8d422713705 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_app.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_app.h
@@ -433,4 +433,6 @@ int nfp_app_nic_vnic_alloc(struct nfp_app *app, struct nfp_net *nn,
 int nfp_app_nic_vnic_init_phy_port(struct nfp_pf *pf, struct nfp_app *app,
 				   struct nfp_net *nn, unsigned int id);
 
+struct devlink *nfp_devlink_get_devlink(struct net_device *netdev);
+
 #endif
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_devlink.c b/drivers/net/ethernet/netronome/nfp/nfp_devlink.c
index db2da99f6aa7..e9eca99cf493 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_devlink.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_devlink.c
@@ -376,3 +376,14 @@ void nfp_devlink_port_unregister(struct nfp_port *port)
 {
 	devlink_port_unregister(&port->dl_port);
 }
+
+struct devlink *nfp_devlink_get_devlink(struct net_device *netdev)
+{
+	struct nfp_app *app;
+
+	app = nfp_app_from_netdev(netdev);
+	if (!app)
+		return NULL;
+
+	return priv_to_devlink(app->pf);
+}
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 776f6c07701b..6d1b8816552e 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -3531,6 +3531,7 @@ const struct net_device_ops nfp_net_netdev_ops = {
 	.ndo_udp_tunnel_del	= nfp_net_del_vxlan_port,
 	.ndo_bpf		= nfp_net_xdp,
 	.ndo_get_port_parent_id	= nfp_port_get_port_parent_id,
+	.ndo_get_devlink	= nfp_devlink_get_devlink,
 };
 
 /**
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c b/drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c
index 8f189149efc5..690b62718dbb 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c
@@ -1234,28 +1234,6 @@ static int nfp_net_set_channels(struct net_device *netdev,
 	return nfp_net_set_num_rings(nn, total_rx, total_tx);
 }
 
-static int
-nfp_net_flash_device(struct net_device *netdev, struct ethtool_flash *flash)
-{
-	struct nfp_app *app;
-	int ret;
-
-	if (flash->region != ETHTOOL_FLASH_ALL_REGIONS)
-		return -EOPNOTSUPP;
-
-	app = nfp_app_from_netdev(netdev);
-	if (!app)
-		return -EOPNOTSUPP;
-
-	dev_hold(netdev);
-	rtnl_unlock();
-	ret = nfp_flash_update_common(app->pf, flash->data, NULL);
-	rtnl_lock();
-	dev_put(netdev);
-
-	return ret;
-}
-
 static const struct ethtool_ops nfp_net_ethtool_ops = {
 	.get_drvinfo		= nfp_net_get_drvinfo,
 	.get_link		= ethtool_op_get_link,
@@ -1266,7 +1244,6 @@ static const struct ethtool_ops nfp_net_ethtool_ops = {
 	.get_sset_count		= nfp_net_get_sset_count,
 	.get_rxnfc		= nfp_net_get_rxnfc,
 	.set_rxnfc		= nfp_net_set_rxnfc,
-	.flash_device		= nfp_net_flash_device,
 	.get_rxfh_indir_size	= nfp_net_get_rxfh_indir_size,
 	.get_rxfh_key_size	= nfp_net_get_rxfh_key_size,
 	.get_rxfh		= nfp_net_get_rxfh,
@@ -1292,7 +1269,6 @@ const struct ethtool_ops nfp_port_ethtool_ops = {
 	.get_strings		= nfp_port_get_strings,
 	.get_ethtool_stats	= nfp_port_get_stats,
 	.get_sset_count		= nfp_port_get_sset_count,
-	.flash_device		= nfp_net_flash_device,
 	.set_dump		= nfp_app_set_dump,
 	.get_dump_flag		= nfp_app_get_dump_flag,
 	.get_dump_data		= nfp_app_get_dump_data,
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_repr.c b/drivers/net/ethernet/netronome/nfp/nfp_net_repr.c
index 62839807e21e..d2c803bb4e56 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_repr.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_repr.c
@@ -273,6 +273,7 @@ const struct net_device_ops nfp_repr_netdev_ops = {
 	.ndo_set_features	= nfp_port_set_features,
 	.ndo_set_mac_address    = eth_mac_addr,
 	.ndo_get_port_parent_id	= nfp_port_get_port_parent_id,
+	.ndo_get_devlink	= nfp_devlink_get_devlink,
 };
 
 void