/* * net/switchdev/switchdev.c - Switch device API * Copyright (c) 2014-2015 Jiri Pirko <jiri@resnulli.us> * Copyright (c) 2014-2015 Scott Feldman <sfeldma@gmail.com> * * 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 <linux/kernel.h> #include <linux/types.h> #include <linux/init.h> #include <linux/mutex.h> #include <linux/notifier.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/if_bridge.h> #include <linux/list.h> #include <linux/workqueue.h> #include <linux/if_vlan.h> #include <linux/rtnetlink.h> #include <net/switchdev.h> /** * switchdev_trans_item_enqueue - Enqueue data item to transaction queue * * @trans: transaction * @data: pointer to data being queued * @destructor: data destructor * @tritem: transaction item being queued * * Enqeueue data item to transaction queue. tritem is typically placed in * cointainter pointed at by data pointer. Destructor is called on * transaction abort and after successful commit phase in case * the caller did not dequeue the item before. */ void switchdev_trans_item_enqueue(struct switchdev_trans *trans, void *data, void (*destructor)(void const *), struct switchdev_trans_item *tritem) { tritem->data = data; tritem->destructor = destructor; list_add_tail(&tritem->list, &trans->item_list); } EXPORT_SYMBOL_GPL(switchdev_trans_item_enqueue); static struct switchdev_trans_item * __switchdev_trans_item_dequeue(struct switchdev_trans *trans) { struct switchdev_trans_item *tritem; if (list_empty(&trans->item_list)) return NULL; tritem = list_first_entry(&trans->item_list, struct switchdev_trans_item, list); list_del(&tritem->list); return tritem; } /** * switchdev_trans_item_dequeue - Dequeue data item from transaction queue * * @trans: transaction */ void *switchdev_trans_item_dequeue(struct switchdev_trans *trans) { struct switchdev_trans_item *tritem; tritem = __switchdev_trans_item_dequeue(trans); BUG_ON(!tritem); return tritem->data; } EXPORT_SYMBOL_GPL(switchdev_trans_item_dequeue); static void switchdev_trans_init(struct switchdev_trans *trans) { INIT_LIST_HEAD(&trans->item_list); } static void switchdev_trans_items_destroy(struct switchdev_trans *trans) { struct switchdev_trans_item *tritem; while ((tritem = __switchdev_trans_item_dequeue(trans))) tritem->destructor(tritem->data); } static void switchdev_trans_items_warn_destroy(struct net_device *dev, struct switchdev_trans *trans) { WARN(!list_empty(&trans->item_list), "%s: transaction item queue is not empty.\n", dev->name); switchdev_trans_items_destroy(trans); } static LIST_HEAD(deferred); static DEFINE_SPINLOCK(deferred_lock); typedef void switchdev_deferred_func_t(struct net_device *dev, const void *data); struct switchdev_deferred_item { struct list_head list; struct net_device *dev; switchdev_deferred_func_t *func; unsigned long data[0]; }; static struct switchdev_deferred_item *switchdev_deferred_dequeue(void) { struct switchdev_deferred_item *dfitem; spin_lock_bh(&deferred_lock); if (list_empty(&deferred)) { dfitem = NULL; goto unlock; } dfitem = list_first_entry(&deferred, struct switchdev_deferred_item, list); list_del(&dfitem->list); unlock: spin_unlock_bh(&deferred_lock); return dfitem; } /** * switchdev_deferred_process - Process ops in deferred queue * * Called to flush the ops currently queued in deferred ops queue. * rtnl_lock must be held. */ void switchdev_deferred_process(void) { struct switchdev_deferred_item *dfitem; ASSERT_RTNL(); while ((dfitem = switchdev_deferred_dequeue())) { dfitem->func(dfitem->dev, dfitem->data); dev_put(dfitem->dev); kfree(dfitem); } } EXPORT_SYMBOL_GPL(switchdev_deferred_process); static void switchdev_deferred_process_work(struct work_struct *work) { rtnl_lock(); switchdev_deferred_process(); rtnl_unlock(); } static DECLARE_WORK(deferred_process_work, switchdev_deferred_process_work); static int switchdev_deferred_enqueue(struct net_device *dev, const void *data, size_t data_len, switchdev_deferred_func_t *func) { struct switchdev_deferred_item *dfitem; dfitem = kmalloc(sizeof(*dfitem) + data_len, GFP_ATOMIC); if (!dfitem) return -ENOMEM; dfitem->dev = dev; dfitem->func = func; memcpy(dfitem->data, data, data_len); dev_hold(dev); spin_lock_bh(&deferred_lock); list_add_tail(&dfitem->list, &deferred); spin_unlock_bh(&deferred_lock); schedule_work(&deferred_process_work); return 0; } /** * switchdev_port_attr_get - Get port attribute * * @dev: port device * @attr: attribute to get */ int switchdev_port_attr_get(struct net_device *dev, struct switchdev_attr *attr) { const struct switchdev_ops *ops = dev->switchdev_ops; struct net_device *lower_dev; struct list_head *iter; struct switchdev_attr first = { .id = SWITCHDEV_ATTR_ID_UNDEFINED }; int err = -EOPNOTSUPP; if (ops && ops->switchdev_port_attr_get) return ops->switchdev_port_attr_get(dev, attr); if (attr->flags & SWITCHDEV_F_NO_RECURSE) return err; /* Switch device port(s) may be stacked under * bond/team/vlan dev, so recurse down to get attr on * each port. Return -ENODATA if attr values don't * compare across ports. */ netdev_for_each_lower_dev(dev, lower_dev, iter) { err = switchdev_port_attr_get(lower_dev, attr); if (err) break; if (first.id == SWITCHDEV_ATTR_ID_UNDEFINED) first = *attr; else if (memcmp(&first, attr, sizeof(*attr))) return -ENODATA; } return err; } EXPORT_SYMBOL_GPL(switchdev_port_attr_get); static int __switchdev_port_attr_set(struct net_device *dev, const struct switchdev_attr *attr, struct switchdev_trans *trans) { const struct switchdev_ops *ops = dev->switchdev_ops; struct net_device *lower_dev; struct list_head *iter; int err = -EOPNOTSUPP; if (ops && ops->switchdev_port_attr_set) { err = ops->switchdev_port_attr_set(dev, attr, trans); goto done; } if (attr->flags & SWITCHDEV_F_NO_RECURSE) goto done; /* Switch device port(s) may be stacked under * bond/team/vlan dev, so recurse down to set attr on * each port. */ netdev_for_each_lower_dev(dev, lower_dev, iter) { err = __switchdev_port_attr_set(lower_dev, attr, trans); if (err) break; } done: if (err == -EOPNOTSUPP && attr->flags & SWITCHDEV_F_SKIP_EOPNOTSUPP) err = 0; return err; } static int switchdev_port_attr_set_now(struct net_device *dev, const struct switchdev_attr *attr) { struct switchdev_trans trans; int err; switchdev_trans_init(&trans); /* Phase I: prepare for attr set. Driver/device should fail * here if there are going to be issues in the commit phase, * such as lack of resources or support. The driver/device * should reserve resources needed for the commit phase here, * but should not commit the attr. */ trans.ph_prepare = true; err = __switchdev_port_attr_set(dev, attr, &trans); if (err) { /* Prepare phase failed: abort the transaction. Any * resources reserved in the prepare phase are * released. */ if (err != -EOPNOTSUPP) switchdev_trans_items_destroy(&trans); return err; } /* Phase II: commit attr set. This cannot fail as a fault * of driver/device. If it does, it's a bug in the driver/device * because the driver said everythings was OK in phase I. */ trans.ph_prepare = false; err = __switchdev_port_attr_set(dev, attr, &trans); WARN(err, "%s: Commit of attribute (id=%d) failed.\n", dev->name, attr->id); switchdev_trans_items_warn_destroy(dev, &trans); return err; } static void switchdev_port_attr_set_deferred(struct net_device *dev, const void *data) { const struct switchdev_attr *attr = data; int err; err = switchdev_port_attr_set_now(dev, attr); if (err && err != -EOPNOTSUPP) netdev_err(dev, "failed (err=%d) to set attribute (id=%d)\n", err, attr->id); if (attr->complete) attr->complete(dev, err, attr->complete_priv); } static int switchdev_port_attr_set_defer(struct net_device *dev, const struct switchdev_attr *attr) { return switchdev_deferred_enqueue(dev, attr, sizeof(*attr), switchdev_port_attr_set_deferred); } /** * switchdev_port_attr_set - Set port attribute * * @dev: port device * @attr: attribute to set * * Use a 2-phase prepare-commit transaction model to ensure * system is not left in a partially updated state due to * failure from driver/device. * * rtnl_lock must be held and must not be in atomic section, * in case SWITCHDEV_F_DEFER flag is not set. */ int switchdev_port_attr_set(struct net_device *dev, const struct switchdev_attr *attr) { if (attr->flags & SWITCHDEV_F_DEFER) return switchdev_port_attr_set_defer(dev, attr); ASSERT_RTNL(); return switchdev_port_attr_set_now(dev, attr); } EXPORT_SYMBOL_GPL(switchdev_port_attr_set); static size_t switchdev_obj_size(const struct switchdev_obj *obj) { switch (obj->id) { case SWITCHDEV_OBJ_ID_PORT_VLAN: return sizeof(struct switchdev_obj_port_vlan); case SWITCHDEV_OBJ_ID_PORT_MDB: return sizeof(struct switchdev_obj_port_mdb); default: BUG(); } return 0; } static int __switchdev_port_obj_add(struct net_device *dev, const struct switchdev_obj *obj, struct switchdev_trans *trans) { const struct switchdev_ops *ops = dev->switchdev_ops; struct net_device *lower_dev; struct list_head *iter; int err = -EOPNOTSUPP; if (ops && ops->switchdev_port_obj_add) return ops->switchdev_port_obj_add(dev, obj, trans); /* Switch device port(s) may be stacked under * bond/team/vlan dev, so recurse down to add object on * each port. */ netdev_for_each_lower_dev(dev, lower_dev, iter) { err = __switchdev_port_obj_add(lower_dev, obj, trans); if (err) break; } return err; } static int switchdev_port_obj_add_now(struct net_device *dev, const struct switchdev_obj *obj) { struct switchdev_trans trans; int err; ASSERT_RTNL(); switchdev_trans_init(&trans); /* Phase I: prepare for obj add. Driver/device should fail * here if there are going to be issues in the commit phase, * such as lack of resources or support. The driver/device * should reserve resources needed for the commit phase here, * but should not commit the obj. */ trans.ph_prepare = true; err = __switchdev_port_obj_add(dev, obj, &trans); if (err) { /* Prepare phase failed: abort the transaction. Any * resources reserved in the prepare phase are * released. */ if (err != -EOPNOTSUPP) switchdev_trans_items_destroy(&trans); return err; } /* Phase II: commit obj add. This cannot fail as a fault * of driver/device. If it does, it's a bug in the driver/device * because the driver said everythings was OK in phase I. */ trans.ph_prepare = false; err = __switchdev_port_obj_add(dev, obj, &trans); WARN(err, "%s: Commit of object (id=%d) failed.\n", dev->name, obj->id); switchdev_trans_items_warn_destroy(dev, &trans); return err; } static void switchdev_port_obj_add_deferred(struct net_device *dev, const void *data) { const struct switchdev_obj *obj = data; int err; err = switchdev_port_obj_add_now(dev, obj); if (err && err != -EOPNOTSUPP) netdev_err(dev, "failed (err=%d) to add object (id=%d)\n", err, obj->id); if (obj->complete) obj->complete(dev, err, obj->complete_priv); } static int switchdev_port_obj_add_defer(struct net_device *dev, const struct switchdev_obj *obj) { return switchdev_deferred_enqueue(dev, obj, switchdev_obj_size(obj), switchdev_port_obj_add_deferred); } /** * switchdev_port_obj_add - Add port object * * @dev: port device * @id: object ID * @obj: object to add * * Use a 2-phase prepare-commit transaction model to ensure * system is not left in a partially updated state due to * failure from driver/device. * * rtnl_lock must be held and must not be in atomic section, * in case SWITCHDEV_F_DEFER flag is not set. */ int switchdev_port_obj_add(struct net_device *dev, const struct switchdev_obj *obj) { if (obj->flags & SWITCHDEV_F_DEFER) return switchdev_port_obj_add_defer(dev, obj); ASSERT_RTNL(); return switchdev_port_obj_add_now(dev, obj); } EXPORT_SYMBOL_GPL(switchdev_port_obj_add); static int switchdev_port_obj_del_now(struct net_device *dev, const struct switchdev_obj *obj) { const struct switchdev_ops *ops = dev->switchdev_ops; struct net_device *lower_dev; struct list_head *iter; int err = -EOPNOTSUPP; if (ops && ops->switchdev_port_obj_del) return ops->switchdev_port_obj_del(dev, obj); /* Switch device port(s) may be stacked under * bond/team/vlan dev, so recurse down to delete object on * each port. */ netdev_for_each_lower_dev(dev, lower_dev, iter) { err = switchdev_port_obj_del_now(lower_dev, obj); if (err) break; } return err; } static void switchdev_port_obj_del_deferred(struct net_device *dev, const void *data) { const struct switchdev_obj *obj = data; int err; err = switchdev_port_obj_del_now(dev, obj); if (err && err != -EOPNOTSUPP) netdev_err(dev, "failed (err=%d) to del object (id=%d)\n", err, obj->id); if (obj->complete) obj->complete(dev, err, obj->complete_priv); } static int switchdev_port_obj_del_defer(struct net_device *dev, const struct switchdev_obj *obj) { return switchdev_deferred_enqueue(dev, obj, switchdev_obj_size(obj), switchdev_port_obj_del_deferred); } /** * switchdev_port_obj_del - Delete port object * * @dev: port device * @id: object ID * @obj: object to delete * * rtnl_lock must be held and must not be in atomic section, * in case SWITCHDEV_F_DEFER flag is not set. */ int switchdev_port_obj_del(struct net_device *dev, const struct switchdev_obj *obj) { if (obj->flags & SWITCHDEV_F_DEFER) return switchdev_port_obj_del_defer(dev, obj); ASSERT_RTNL(); return switchdev_port_obj_del_now(dev, obj); } EXPORT_SYMBOL_GPL(switchdev_port_obj_del); static ATOMIC_NOTIFIER_HEAD(switchdev_notif_chain); /** * register_switchdev_notifier - Register notifier * @nb: notifier_block * * Register switch device notifier. */ int register_switchdev_notifier(struct notifier_block *nb) { return atomic_notifier_chain_register(&switchdev_notif_chain, nb); } EXPORT_SYMBOL_GPL(register_switchdev_notifier); /** * unregister_switchdev_notifier - Unregister notifier * @nb: notifier_block * * Unregister switch device notifier. */ int unregister_switchdev_notifier(struct notifier_block *nb) { return atomic_notifier_chain_unregister(&switchdev_notif_chain, nb); } EXPORT_SYMBOL_GPL(unregister_switchdev_notifier); /** * call_switchdev_notifiers - Call notifiers * @val: value passed unmodified to notifier function * @dev: port device * @info: notifier information data * * Call all network notifier blocks. */ int call_switchdev_notifiers(unsigned long val, struct net_device *dev, struct switchdev_notifier_info *info) { info->dev = dev; return atomic_notifier_call_chain(&switchdev_notif_chain, val, info); } EXPORT_SYMBOL_GPL(call_switchdev_notifiers); bool switchdev_port_same_parent_id(struct net_device *a, struct net_device *b) { struct switchdev_attr a_attr = { .orig_dev = a, .id = SWITCHDEV_ATTR_ID_PORT_PARENT_ID, }; struct switchdev_attr b_attr = { .orig_dev = b, .id = SWITCHDEV_ATTR_ID_PORT_PARENT_ID, }; if (switchdev_port_attr_get(a, &a_attr) || switchdev_port_attr_get(b, &b_attr)) return false; return netdev_phys_item_id_same(&a_attr.u.ppid, &b_attr.u.ppid); } EXPORT_SYMBOL_GPL(switchdev_port_same_parent_id);