net: devlink: turn devlink into a built-in

Being able to build devlink as a module causes growing pains.
First all drivers had to add a meta dependency to make sure
they are not built in when devlink is built as a module.  Now
we are struggling to invoke ethtool compat code reliably.

Make devlink code built-in, users can still not build it at
all but the dynamically loadable module option is removed.

Signed-off-by: Jakub Kicinski <[email protected]>
Reviewed-by: Florian Fainelli <[email protected]>
Acked-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: Jakub Kicinski

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---

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---

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

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---

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

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

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

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.
 

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

include/net/devlink.h

@@ -707,6 +707,10 @@ devlink_health_reporter_priv(struct devlink_health_reporter *reporter);
 int devlink_health_report(struct devlink_health_reporter *reporter,
 			  const char *msg, void *priv_ctx);
 
+void devlink_compat_running_version(struct net_device *dev,
+				    char *buf, size_t len);
+int devlink_compat_flash_update(struct net_device *dev, const char *file_name);
+
 #else
 
 static inline struct devlink *devlink_alloc(const struct devlink_ops *ops,
@@ -1190,13 +1194,7 @@ devlink_health_report(struct devlink_health_reporter *reporter,
 {
 	return 0;
 }
-#endif
 
-#if IS_REACHABLE(CONFIG_NET_DEVLINK)
-void devlink_compat_running_version(struct net_device *dev,
-				    char *buf, size_t len);
-int devlink_compat_flash_update(struct net_device *dev, const char *file_name);
-#else
 static inline void
 devlink_compat_running_version(struct net_device *dev, char *buf, size_t len)
 {

net/Kconfig

@@ -429,21 +429,12 @@ config NET_SOCK_MSG
 	  with the help of BPF programs.
 
 config NET_DEVLINK
-	tristate "Network physical/parent device Netlink interface"
+	bool "Network physical/parent device Netlink interface"
 	help
 	  Network physical/parent device Netlink interface provides
 	  infrastructure to support access to physical chip-wide config and
 	  monitoring.
 
-config MAY_USE_DEVLINK
-	tristate
-	default m if NET_DEVLINK=m
-	default y if NET_DEVLINK=y || NET_DEVLINK=n
-	help
-	  Drivers using the devlink infrastructure should have a dependency
-	  on MAY_USE_DEVLINK to ensure they do not cause link errors when
-	  devlink is a loadable module and the driver using it is built-in.
-
 config PAGE_POOL
        bool
 

net/core/devlink.c

@@ -6482,20 +6482,9 @@ int devlink_compat_flash_update(struct net_device *dev, const char *file_name)
 	return -EOPNOTSUPP;
 }
 
-static int __init devlink_module_init(void)
+static int __init devlink_init(void)
 {
 	return genl_register_family(&devlink_nl_family);
 }
 
-static void __exit devlink_module_exit(void)
-{
-	genl_unregister_family(&devlink_nl_family);
-}
-
-module_init(devlink_module_init);
-module_exit(devlink_module_exit);
-
-MODULE_LICENSE("GPL v2");
-MODULE_AUTHOR("Jiri Pirko <[email protected]>");
-MODULE_DESCRIPTION("Network physical device Netlink interface");
-MODULE_ALIAS_GENL_FAMILY(DEVLINK_GENL_NAME);
+subsys_initcall(devlink_init);

net/dsa/Kconfig

@@ -6,7 +6,7 @@ config HAVE_NET_DSA
 
 config NET_DSA
 	tristate "Distributed Switch Architecture"
-	depends on HAVE_NET_DSA && MAY_USE_DEVLINK
+	depends on HAVE_NET_DSA
 	depends on BRIDGE || BRIDGE=n
 	select NET_SWITCHDEV
 	select PHYLINK