From 007f790c8276271de26416f90d55561bcc96588a Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Fri, 28 Nov 2014 14:34:17 +0100 Subject: [PATCH] net: introduce generic switch devices support The goal of this is to provide a possibility to support various switch chips. Drivers should implement relevant ndos to do so. Now there is only one ndo defined: - for getting physical switch id is in place. Note that user can use random port netdevice to access the switch. Signed-off-by: Jiri Pirko Reviewed-by: Thomas Graf Acked-by: Andy Gospodarek Signed-off-by: David S. Miller --- Documentation/networking/switchdev.txt | 59 ++++++++++++++++++++++++++ MAINTAINERS | 7 +++ include/linux/netdevice.h | 10 +++++ include/net/switchdev.h | 30 +++++++++++++ net/Kconfig | 1 + net/Makefile | 3 ++ net/switchdev/Kconfig | 13 ++++++ net/switchdev/Makefile | 5 +++ net/switchdev/switchdev.c | 33 ++++++++++++++ 9 files changed, 161 insertions(+) create mode 100644 Documentation/networking/switchdev.txt create mode 100644 include/net/switchdev.h create mode 100644 net/switchdev/Kconfig create mode 100644 net/switchdev/Makefile create mode 100644 net/switchdev/switchdev.c diff --git a/Documentation/networking/switchdev.txt b/Documentation/networking/switchdev.txt new file mode 100644 index 000000000000..f981a9295a39 --- /dev/null +++ b/Documentation/networking/switchdev.txt @@ -0,0 +1,59 @@ +Switch (and switch-ish) device drivers HOWTO +=========================== + +Please note that the word "switch" is here used in very generic meaning. +This include devices supporting L2/L3 but also various flow offloading chips, +including switches embedded into SR-IOV NICs. + +Lets describe a topology a bit. Imagine the following example: + + +----------------------------+ +---------------+ + | SOME switch chip | | CPU | + +----------------------------+ +---------------+ + port1 port2 port3 port4 MNGMNT | PCI-E | + | | | | | +---------------+ + PHY PHY | | | | NIC0 NIC1 + | | | | | | + | | +- PCI-E -+ | | + | +------- MII -------+ | + +------------- MII ------------+ + +In this example, there are two independent lines between the switch silicon +and CPU. NIC0 and NIC1 drivers are not aware of a switch presence. They are +separate from the switch driver. SOME switch chip is by managed by a driver +via PCI-E device MNGMNT. Note that MNGMNT device, NIC0 and NIC1 may be +connected to some other type of bus. + +Now, for the previous example show the representation in kernel: + + +----------------------------+ +---------------+ + | SOME switch chip | | CPU | + +----------------------------+ +---------------+ + sw0p0 sw0p1 sw0p2 sw0p3 MNGMNT | PCI-E | + | | | | | +---------------+ + PHY PHY | | | | eth0 eth1 + | | | | | | + | | +- PCI-E -+ | | + | +------- MII -------+ | + +------------- MII ------------+ + +Lets call the example switch driver for SOME switch chip "SOMEswitch". This +driver takes care of PCI-E device MNGMNT. There is a netdevice instance sw0pX +created for each port of a switch. These netdevices are instances +of "SOMEswitch" driver. sw0pX netdevices serve as a "representation" +of the switch chip. eth0 and eth1 are instances of some other existing driver. + +The only difference of the switch-port netdevice from the ordinary netdevice +is that is implements couple more NDOs: + + ndo_switch_parent_id_get - This returns the same ID for two port netdevices + of the same physical switch chip. This is + mandatory to be implemented by all switch drivers + and serves the caller for recognition of a port + netdevice. + ndo_switch_parent_* - Functions that serve for a manipulation of the switch + chip itself (it can be though of as a "parent" of the + port, therefore the name). They are not port-specific. + Caller might use arbitrary port netdevice of the same + switch and it will make no difference. + ndo_switch_port_* - Functions that serve for a port-specific manipulation. diff --git a/MAINTAINERS b/MAINTAINERS index 6b880deae3d2..3aba0ac2d5a3 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9059,6 +9059,13 @@ F: lib/swiotlb.c F: arch/*/kernel/pci-swiotlb.c F: include/linux/swiotlb.h +SWITCHDEV +M: Jiri Pirko +L: netdev@vger.kernel.org +S: Supported +F: net/switchdev/ +F: include/net/switchdev.h + SYNOPSYS ARC ARCHITECTURE M: Vineet Gupta S: Supported diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 4bd41d72559d..3603f31e78f3 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1018,6 +1018,12 @@ typedef u16 (*select_queue_fallback_t)(struct net_device *dev, * performing GSO on a packet. The device returns true if it is * able to GSO the packet, false otherwise. If the return value is * false the stack will do software GSO. + * + * int (*ndo_switch_parent_id_get)(struct net_device *dev, + * struct netdev_phys_item_id *psid); + * Called to get an ID of the switch chip this port is part of. + * If driver implements this, it indicates that it represents a port + * of a switch chip. */ struct net_device_ops { int (*ndo_init)(struct net_device *dev); @@ -1171,6 +1177,10 @@ struct net_device_ops { int (*ndo_get_lock_subclass)(struct net_device *dev); bool (*ndo_gso_check) (struct sk_buff *skb, struct net_device *dev); +#ifdef CONFIG_NET_SWITCHDEV + int (*ndo_switch_parent_id_get)(struct net_device *dev, + struct netdev_phys_item_id *psid); +#endif }; /** diff --git a/include/net/switchdev.h b/include/net/switchdev.h new file mode 100644 index 000000000000..7a52360a1446 --- /dev/null +++ b/include/net/switchdev.h @@ -0,0 +1,30 @@ +/* + * include/net/switchdev.h - Switch device API + * Copyright (c) 2014 Jiri Pirko + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ +#ifndef _LINUX_SWITCHDEV_H_ +#define _LINUX_SWITCHDEV_H_ + +#include + +#ifdef CONFIG_NET_SWITCHDEV + +int netdev_switch_parent_id_get(struct net_device *dev, + struct netdev_phys_item_id *psid); + +#else + +static inline int netdev_switch_parent_id_get(struct net_device *dev, + struct netdev_phys_item_id *psid) +{ + return -EOPNOTSUPP; +} + +#endif + +#endif /* _LINUX_SWITCHDEV_H_ */ diff --git a/net/Kconfig b/net/Kconfig index 99815b5454bf..ff9ffc17fa0e 100644 --- a/net/Kconfig +++ b/net/Kconfig @@ -228,6 +228,7 @@ source "net/vmw_vsock/Kconfig" source "net/netlink/Kconfig" source "net/mpls/Kconfig" source "net/hsr/Kconfig" +source "net/switchdev/Kconfig" config RPS boolean diff --git a/net/Makefile b/net/Makefile index 7ed1970074b0..95fc694e4ddc 100644 --- a/net/Makefile +++ b/net/Makefile @@ -73,3 +73,6 @@ obj-$(CONFIG_OPENVSWITCH) += openvswitch/ obj-$(CONFIG_VSOCKETS) += vmw_vsock/ obj-$(CONFIG_NET_MPLS_GSO) += mpls/ obj-$(CONFIG_HSR) += hsr/ +ifneq ($(CONFIG_NET_SWITCHDEV),) +obj-y += switchdev/ +endif diff --git a/net/switchdev/Kconfig b/net/switchdev/Kconfig new file mode 100644 index 000000000000..155754588fd6 --- /dev/null +++ b/net/switchdev/Kconfig @@ -0,0 +1,13 @@ +# +# Configuration for Switch device support +# + +config NET_SWITCHDEV + boolean "Switch (and switch-ish) device support (EXPERIMENTAL)" + depends on INET + ---help--- + This module provides glue between core networking code and device + drivers in order to support hardware switch chips in very generic + meaning of the word "switch". This include devices supporting L2/L3 but + also various flow offloading chips, including switches embedded into + SR-IOV NICs. diff --git a/net/switchdev/Makefile b/net/switchdev/Makefile new file mode 100644 index 000000000000..5ed63ed324d0 --- /dev/null +++ b/net/switchdev/Makefile @@ -0,0 +1,5 @@ +# +# Makefile for the Switch device API +# + +obj-$(CONFIG_NET_SWITCHDEV) += switchdev.o diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c new file mode 100644 index 000000000000..66973deaae56 --- /dev/null +++ b/net/switchdev/switchdev.c @@ -0,0 +1,33 @@ +/* + * net/switchdev/switchdev.c - Switch device API + * Copyright (c) 2014 Jiri Pirko + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include +#include +#include +#include +#include + +/** + * netdev_switch_parent_id_get - Get ID of a switch + * @dev: port device + * @psid: switch ID + * + * Get ID of a switch this port is part of. + */ +int netdev_switch_parent_id_get(struct net_device *dev, + struct netdev_phys_item_id *psid) +{ + const struct net_device_ops *ops = dev->netdev_ops; + + if (!ops->ndo_switch_parent_id_get) + return -EOPNOTSUPP; + return ops->ndo_switch_parent_id_get(dev, psid); +} +EXPORT_SYMBOL(netdev_switch_parent_id_get); -- 2.20.1