From 37923ed6b8cea94d7d76038e2f72c57a0b45daab Mon Sep 17 00:00:00 2001 From: David Ahern Date: Tue, 27 Mar 2018 18:22:00 -0700 Subject: [PATCH] netdevsim: Add simple FIB resource controller via devlink Add devlink support to netdevsim and use it to implement a simple, profile based resource controller. Only one controller is needed per namespace, so the first netdevsim netdevice in a namespace registers with devlink. If that device is deleted, the resource settings are deleted. The resource controller allows a user to limit the number of IPv4 and IPv6 FIB entries and FIB rules. The resource paths are: /IPv4 /IPv4/fib /IPv4/fib-rules /IPv6 /IPv6/fib /IPv6/fib-rules The IPv4 and IPv6 top level resources are unlimited in size and can not be changed. From there, the number of FIB entries and FIB rule entries are unlimited by default. A user can specify a limit for the fib and fib-rules resources: $ devlink resource set netdevsim/netdevsim0 path /IPv4/fib size 96 $ devlink resource set netdevsim/netdevsim0 path /IPv4/fib-rules size 16 $ devlink resource set netdevsim/netdevsim0 path /IPv6/fib size 64 $ devlink resource set netdevsim/netdevsim0 path /IPv6/fib-rules size 16 $ devlink dev reload netdevsim/netdevsim0 such that the number of rules or routes is limited (96 ipv4 routes in the example above): $ for n in $(seq 1 32); do ip ro add 10.99.$n.0/24 dev eth1; done Error: netdevsim: Exceeded number of supported fib entries. $ devlink resource show netdevsim/netdevsim0 netdevsim/netdevsim0: name IPv4 size unlimited unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables non resources: name fib size 96 occ 96 unit entry size_min 0 size_max unlimited size_gran 1 dpipe_tables ... With this template in place for resource management, it is fairly trivial to extend and shows one way to implement a simple counter based resource controller typical of network profiles. Currently, devlink only supports initial namespace. Code is in place to adapt netdevsim to a per namespace controller once the network namespace issues are resolved. Signed-off-by: David Ahern Signed-off-by: David S. Miller --- drivers/net/Kconfig | 1 + drivers/net/netdevsim/Makefile | 4 + drivers/net/netdevsim/devlink.c | 294 ++++++++++++++++++++++++++++++ drivers/net/netdevsim/fib.c | 263 ++++++++++++++++++++++++++ drivers/net/netdevsim/netdev.c | 12 +- drivers/net/netdevsim/netdevsim.h | 43 +++++ 6 files changed, 616 insertions(+), 1 deletion(-) create mode 100644 drivers/net/netdevsim/devlink.c create mode 100644 drivers/net/netdevsim/fib.c diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index 08b85215c2be..891846655000 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -500,6 +500,7 @@ 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/netdevsim/Makefile b/drivers/net/netdevsim/Makefile index 09388c06171d..449b2a1a1800 100644 --- a/drivers/net/netdevsim/Makefile +++ b/drivers/net/netdevsim/Makefile @@ -9,3 +9,7 @@ ifeq ($(CONFIG_BPF_SYSCALL),y) netdevsim-objs += \ bpf.o endif + +ifneq ($(CONFIG_NET_DEVLINK),) +netdevsim-objs += devlink.o fib.o +endif diff --git a/drivers/net/netdevsim/devlink.c b/drivers/net/netdevsim/devlink.c new file mode 100644 index 000000000000..bbdcf064ba10 --- /dev/null +++ b/drivers/net/netdevsim/devlink.c @@ -0,0 +1,294 @@ +/* + * Copyright (c) 2018 Cumulus Networks. All rights reserved. + * Copyright (c) 2018 David Ahern + * + * This software is licensed under the GNU General License Version 2, + * June 1991 as shown in the file COPYING in the top-level directory of this + * source tree. + * + * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" + * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, + * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE + * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME + * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. + */ + +#include +#include +#include + +#include "netdevsim.h" + +static unsigned int nsim_devlink_id; + +/* place holder until devlink and namespaces is sorted out */ +static struct net *nsim_devlink_net(struct devlink *devlink) +{ + return &init_net; +} + +/* IPv4 + */ +static u64 nsim_ipv4_fib_resource_occ_get(struct devlink *devlink) +{ + struct net *net = nsim_devlink_net(devlink); + + return nsim_fib_get_val(net, NSIM_RESOURCE_IPV4_FIB, false); +} + +static struct devlink_resource_ops nsim_ipv4_fib_res_ops = { + .occ_get = nsim_ipv4_fib_resource_occ_get, +}; + +static u64 nsim_ipv4_fib_rules_res_occ_get(struct devlink *devlink) +{ + struct net *net = nsim_devlink_net(devlink); + + return nsim_fib_get_val(net, NSIM_RESOURCE_IPV4_FIB_RULES, false); +} + +static struct devlink_resource_ops nsim_ipv4_fib_rules_res_ops = { + .occ_get = nsim_ipv4_fib_rules_res_occ_get, +}; + +/* IPv6 + */ +static u64 nsim_ipv6_fib_resource_occ_get(struct devlink *devlink) +{ + struct net *net = nsim_devlink_net(devlink); + + return nsim_fib_get_val(net, NSIM_RESOURCE_IPV6_FIB, false); +} + +static struct devlink_resource_ops nsim_ipv6_fib_res_ops = { + .occ_get = nsim_ipv6_fib_resource_occ_get, +}; + +static u64 nsim_ipv6_fib_rules_res_occ_get(struct devlink *devlink) +{ + struct net *net = nsim_devlink_net(devlink); + + return nsim_fib_get_val(net, NSIM_RESOURCE_IPV6_FIB_RULES, false); +} + +static struct devlink_resource_ops nsim_ipv6_fib_rules_res_ops = { + .occ_get = nsim_ipv6_fib_rules_res_occ_get, +}; + +static int devlink_resources_register(struct devlink *devlink) +{ + struct devlink_resource_size_params params = { + .size_max = (u64)-1, + .size_granularity = 1, + .unit = DEVLINK_RESOURCE_UNIT_ENTRY + }; + struct net *net = nsim_devlink_net(devlink); + int err; + u64 n; + + /* Resources for IPv4 */ + err = devlink_resource_register(devlink, "IPv4", (u64)-1, + NSIM_RESOURCE_IPV4, + DEVLINK_RESOURCE_ID_PARENT_TOP, + ¶ms, NULL); + if (err) { + pr_err("Failed to register IPv4 top resource\n"); + goto out; + } + + n = nsim_fib_get_val(net, NSIM_RESOURCE_IPV4_FIB, true); + err = devlink_resource_register(devlink, "fib", n, + NSIM_RESOURCE_IPV4_FIB, + NSIM_RESOURCE_IPV4, + ¶ms, &nsim_ipv4_fib_res_ops); + if (err) { + pr_err("Failed to register IPv4 FIB resource\n"); + return err; + } + + n = nsim_fib_get_val(net, NSIM_RESOURCE_IPV4_FIB_RULES, true); + err = devlink_resource_register(devlink, "fib-rules", n, + NSIM_RESOURCE_IPV4_FIB_RULES, + NSIM_RESOURCE_IPV4, + ¶ms, &nsim_ipv4_fib_rules_res_ops); + if (err) { + pr_err("Failed to register IPv4 FIB rules resource\n"); + return err; + } + + /* Resources for IPv6 */ + err = devlink_resource_register(devlink, "IPv6", (u64)-1, + NSIM_RESOURCE_IPV6, + DEVLINK_RESOURCE_ID_PARENT_TOP, + ¶ms, NULL); + if (err) { + pr_err("Failed to register IPv6 top resource\n"); + goto out; + } + + n = nsim_fib_get_val(net, NSIM_RESOURCE_IPV6_FIB, true); + err = devlink_resource_register(devlink, "fib", n, + NSIM_RESOURCE_IPV6_FIB, + NSIM_RESOURCE_IPV6, + ¶ms, &nsim_ipv6_fib_res_ops); + if (err) { + pr_err("Failed to register IPv6 FIB resource\n"); + return err; + } + + n = nsim_fib_get_val(net, NSIM_RESOURCE_IPV6_FIB_RULES, true); + err = devlink_resource_register(devlink, "fib-rules", n, + NSIM_RESOURCE_IPV6_FIB_RULES, + NSIM_RESOURCE_IPV6, + ¶ms, &nsim_ipv6_fib_rules_res_ops); + if (err) { + pr_err("Failed to register IPv6 FIB rules resource\n"); + return err; + } +out: + return err; +} + +static int nsim_devlink_reload(struct devlink *devlink) +{ + enum nsim_resource_id res_ids[] = { + NSIM_RESOURCE_IPV4_FIB, NSIM_RESOURCE_IPV4_FIB_RULES, + NSIM_RESOURCE_IPV6_FIB, NSIM_RESOURCE_IPV6_FIB_RULES + }; + struct net *net = nsim_devlink_net(devlink); + int i; + + for (i = 0; i < ARRAY_SIZE(res_ids); ++i) { + int err; + u64 val; + + err = devlink_resource_size_get(devlink, res_ids[i], &val); + if (!err) { + err = nsim_fib_set_max(net, res_ids[i], val); + if (err) + return err; + } + } + + return 0; +} + +static void nsim_devlink_net_reset(struct net *net) +{ + enum nsim_resource_id res_ids[] = { + NSIM_RESOURCE_IPV4_FIB, NSIM_RESOURCE_IPV4_FIB_RULES, + NSIM_RESOURCE_IPV6_FIB, NSIM_RESOURCE_IPV6_FIB_RULES + }; + int i; + + for (i = 0; i < ARRAY_SIZE(res_ids); ++i) { + if (nsim_fib_set_max(net, res_ids[i], (u64)-1)) { + pr_err("Failed to reset limit for resource %u\n", + res_ids[i]); + } + } +} + +static const struct devlink_ops nsim_devlink_ops = { + .reload = nsim_devlink_reload, +}; + +/* once devlink / namespace issues are sorted out + * this needs to be net in which a devlink instance + * is to be created. e.g., dev_net(ns->netdev) + */ +static struct net *nsim_to_net(struct netdevsim *ns) +{ + return &init_net; +} + +void nsim_devlink_teardown(struct netdevsim *ns) +{ + if (ns->devlink) { + struct net *net = nsim_to_net(ns); + bool *reg_devlink = net_generic(net, nsim_devlink_id); + + devlink_unregister(ns->devlink); + devlink_free(ns->devlink); + ns->devlink = NULL; + + nsim_devlink_net_reset(net); + *reg_devlink = true; + } +} + +void nsim_devlink_setup(struct netdevsim *ns) +{ + struct net *net = nsim_to_net(ns); + bool *reg_devlink = net_generic(net, nsim_devlink_id); + struct devlink *devlink; + int err = -ENOMEM; + + /* only one device per namespace controls devlink */ + if (!*reg_devlink) { + ns->devlink = NULL; + return; + } + + devlink = devlink_alloc(&nsim_devlink_ops, 0); + if (!devlink) + return; + + err = devlink_register(devlink, &ns->dev); + if (err) + goto err_devlink_free; + + err = devlink_resources_register(devlink); + if (err) + goto err_dl_unregister; + + ns->devlink = devlink; + + *reg_devlink = false; + + return; + +err_dl_unregister: + devlink_unregister(devlink); +err_devlink_free: + devlink_free(devlink); +} + +/* Initialize per network namespace state */ +static int __net_init nsim_devlink_netns_init(struct net *net) +{ + bool *reg_devlink = net_generic(net, nsim_devlink_id); + + *reg_devlink = true; + + return 0; +} + +static struct pernet_operations nsim_devlink_net_ops __net_initdata = { + .init = nsim_devlink_netns_init, + .id = &nsim_devlink_id, + .size = sizeof(bool), +}; + +void nsim_devlink_exit(void) +{ + unregister_pernet_subsys(&nsim_devlink_net_ops); + nsim_fib_exit(); +} + +int nsim_devlink_init(void) +{ + int err; + + err = nsim_fib_init(); + if (err) + goto err_out; + + err = register_pernet_subsys(&nsim_devlink_net_ops); + if (err) + nsim_fib_exit(); + +err_out: + return err; +} diff --git a/drivers/net/netdevsim/fib.c b/drivers/net/netdevsim/fib.c new file mode 100644 index 000000000000..0d105bafa261 --- /dev/null +++ b/drivers/net/netdevsim/fib.c @@ -0,0 +1,263 @@ +/* + * Copyright (c) 2018 Cumulus Networks. All rights reserved. + * Copyright (c) 2018 David Ahern + * + * This software is licensed under the GNU General License Version 2, + * June 1991 as shown in the file COPYING in the top-level directory of this + * source tree. + * + * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" + * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, + * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE + * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME + * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. + */ + +#include +#include +#include +#include +#include + +#include "netdevsim.h" + +struct nsim_fib_entry { + u64 max; + u64 num; +}; + +struct nsim_per_fib_data { + struct nsim_fib_entry fib; + struct nsim_fib_entry rules; +}; + +struct nsim_fib_data { + struct nsim_per_fib_data ipv4; + struct nsim_per_fib_data ipv6; +}; + +static unsigned int nsim_fib_net_id; + +u64 nsim_fib_get_val(struct net *net, enum nsim_resource_id res_id, bool max) +{ + struct nsim_fib_data *fib_data = net_generic(net, nsim_fib_net_id); + struct nsim_fib_entry *entry; + + switch (res_id) { + case NSIM_RESOURCE_IPV4_FIB: + entry = &fib_data->ipv4.fib; + break; + case NSIM_RESOURCE_IPV4_FIB_RULES: + entry = &fib_data->ipv4.rules; + break; + case NSIM_RESOURCE_IPV6_FIB: + entry = &fib_data->ipv6.fib; + break; + case NSIM_RESOURCE_IPV6_FIB_RULES: + entry = &fib_data->ipv6.rules; + break; + default: + return 0; + } + + return max ? entry->max : entry->num; +} + +int nsim_fib_set_max(struct net *net, enum nsim_resource_id res_id, u64 val) +{ + struct nsim_fib_data *fib_data = net_generic(net, nsim_fib_net_id); + struct nsim_fib_entry *entry; + int err = 0; + + switch (res_id) { + case NSIM_RESOURCE_IPV4_FIB: + entry = &fib_data->ipv4.fib; + break; + case NSIM_RESOURCE_IPV4_FIB_RULES: + entry = &fib_data->ipv4.rules; + break; + case NSIM_RESOURCE_IPV6_FIB: + entry = &fib_data->ipv6.fib; + break; + case NSIM_RESOURCE_IPV6_FIB_RULES: + entry = &fib_data->ipv6.rules; + break; + default: + return 0; + } + + /* not allowing a new max to be less than curren occupancy + * --> no means of evicting entries + */ + if (val < entry->num) + err = -EINVAL; + else + entry->max = val; + + return err; +} + +static int nsim_fib_rule_account(struct nsim_fib_entry *entry, bool add, + struct netlink_ext_ack *extack) +{ + int err = 0; + + if (add) { + if (entry->num < entry->max) { + entry->num++; + } else { + err = -ENOSPC; + NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported fib rule entries"); + } + } else { + entry->num--; + } + + return err; +} + +static int nsim_fib_rule_event(struct fib_notifier_info *info, bool add) +{ + struct nsim_fib_data *data = net_generic(info->net, nsim_fib_net_id); + struct netlink_ext_ack *extack = info->extack; + int err = 0; + + switch (info->family) { + case AF_INET: + err = nsim_fib_rule_account(&data->ipv4.rules, add, extack); + break; + case AF_INET6: + err = nsim_fib_rule_account(&data->ipv6.rules, add, extack); + break; + } + + return err; +} + +static int nsim_fib_account(struct nsim_fib_entry *entry, bool add, + struct netlink_ext_ack *extack) +{ + int err = 0; + + if (add) { + if (entry->num < entry->max) { + entry->num++; + } else { + err = -ENOSPC; + NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported fib entries"); + } + } else { + entry->num--; + } + + return err; +} + +static int nsim_fib_event(struct fib_notifier_info *info, bool add) +{ + struct nsim_fib_data *data = net_generic(info->net, nsim_fib_net_id); + struct netlink_ext_ack *extack = info->extack; + int err = 0; + + switch (info->family) { + case AF_INET: + err = nsim_fib_account(&data->ipv4.fib, add, extack); + break; + case AF_INET6: + err = nsim_fib_account(&data->ipv6.fib, add, extack); + break; + } + + return err; +} + +static int nsim_fib_event_nb(struct notifier_block *nb, unsigned long event, + void *ptr) +{ + struct fib_notifier_info *info = ptr; + int err = 0; + + switch (event) { + case FIB_EVENT_RULE_ADD: /* fall through */ + case FIB_EVENT_RULE_DEL: + err = nsim_fib_rule_event(info, event == FIB_EVENT_RULE_ADD); + break; + + case FIB_EVENT_ENTRY_ADD: /* fall through */ + case FIB_EVENT_ENTRY_DEL: + err = nsim_fib_event(info, event == FIB_EVENT_ENTRY_ADD); + break; + } + + return notifier_from_errno(err); +} + +/* inconsistent dump, trying again */ +static void nsim_fib_dump_inconsistent(struct notifier_block *nb) +{ + struct nsim_fib_data *data; + struct net *net; + + rcu_read_lock(); + for_each_net_rcu(net) { + data = net_generic(net, nsim_fib_net_id); + + data->ipv4.fib.num = 0ULL; + data->ipv4.rules.num = 0ULL; + + data->ipv6.fib.num = 0ULL; + data->ipv6.rules.num = 0ULL; + } + rcu_read_unlock(); +} + +static struct notifier_block nsim_fib_nb = { + .notifier_call = nsim_fib_event_nb, +}; + +/* Initialize per network namespace state */ +static int __net_init nsim_fib_netns_init(struct net *net) +{ + struct nsim_fib_data *data = net_generic(net, nsim_fib_net_id); + + data->ipv4.fib.max = (u64)-1; + data->ipv4.rules.max = (u64)-1; + + data->ipv6.fib.max = (u64)-1; + data->ipv6.rules.max = (u64)-1; + + return 0; +} + +static struct pernet_operations nsim_fib_net_ops __net_initdata = { + .init = nsim_fib_netns_init, + .id = &nsim_fib_net_id, + .size = sizeof(struct nsim_fib_data), +}; + +void nsim_fib_exit(void) +{ + unregister_pernet_subsys(&nsim_fib_net_ops); + unregister_fib_notifier(&nsim_fib_nb); +} + +int nsim_fib_init(void) +{ + int err; + + err = register_pernet_subsys(&nsim_fib_net_ops); + if (err < 0) { + pr_err("Failed to register pernet subsystem\n"); + goto err_out; + } + + err = register_fib_notifier(&nsim_fib_nb, nsim_fib_dump_inconsistent); + if (err < 0) { + pr_err("Failed to register fib notifier\n"); + goto err_out; + } + +err_out: + return err; +} diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c index 3fd567928f3d..8b30ab3ea2c2 100644 --- a/drivers/net/netdevsim/netdev.c +++ b/drivers/net/netdevsim/netdev.c @@ -167,6 +167,8 @@ static int nsim_init(struct net_device *dev) SET_NETDEV_DEV(dev, &ns->dev); + nsim_devlink_setup(ns); + return 0; err_bpf_uninit: @@ -180,6 +182,7 @@ static void nsim_uninit(struct net_device *dev) { struct netdevsim *ns = netdev_priv(dev); + nsim_devlink_teardown(ns); debugfs_remove_recursive(ns->ddir); nsim_bpf_uninit(ns); } @@ -478,12 +481,18 @@ static int __init nsim_module_init(void) if (err) goto err_debugfs_destroy; - err = rtnl_link_register(&nsim_link_ops); + err = nsim_devlink_init(); if (err) goto err_unreg_bus; + err = rtnl_link_register(&nsim_link_ops); + if (err) + goto err_dl_fini; + return 0; +err_dl_fini: + nsim_devlink_exit(); err_unreg_bus: bus_unregister(&nsim_bus); err_debugfs_destroy: @@ -494,6 +503,7 @@ err_debugfs_destroy: static void __exit nsim_module_exit(void) { rtnl_link_unregister(&nsim_link_ops); + nsim_devlink_exit(); bus_unregister(&nsim_bus); debugfs_remove_recursive(nsim_ddir); } diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h index ea081c10efb8..afb8cf90c0fd 100644 --- a/drivers/net/netdevsim/netdevsim.h +++ b/drivers/net/netdevsim/netdevsim.h @@ -64,6 +64,9 @@ struct netdevsim { bool bpf_map_accept; struct list_head bpf_bound_maps; +#if IS_ENABLED(CONFIG_NET_DEVLINK) + struct devlink *devlink; +#endif }; extern struct dentry *nsim_ddir; @@ -103,6 +106,46 @@ nsim_bpf_setup_tc_block_cb(enum tc_setup_type type, void *type_data, } #endif +#if IS_ENABLED(CONFIG_NET_DEVLINK) +enum nsim_resource_id { + NSIM_RESOURCE_NONE, /* DEVLINK_RESOURCE_ID_PARENT_TOP */ + NSIM_RESOURCE_IPV4, + NSIM_RESOURCE_IPV4_FIB, + NSIM_RESOURCE_IPV4_FIB_RULES, + NSIM_RESOURCE_IPV6, + NSIM_RESOURCE_IPV6_FIB, + NSIM_RESOURCE_IPV6_FIB_RULES, +}; + +void nsim_devlink_setup(struct netdevsim *ns); +void nsim_devlink_teardown(struct netdevsim *ns); + +int nsim_devlink_init(void); +void nsim_devlink_exit(void); + +int nsim_fib_init(void); +void nsim_fib_exit(void); +u64 nsim_fib_get_val(struct net *net, enum nsim_resource_id res_id, bool max); +int nsim_fib_set_max(struct net *net, enum nsim_resource_id res_id, u64 val); +#else +static inline void nsim_devlink_setup(struct netdevsim *ns) +{ +} + +static inline void nsim_devlink_teardown(struct netdevsim *ns) +{ +} + +static inline int nsim_devlink_init(void) +{ + return 0; +} + +static inline void nsim_devlink_exit(void) +{ +} +#endif + static inline struct netdevsim *to_nsim(struct device *ptr) { return container_of(ptr, struct netdevsim, dev); -- 2.30.2