diff --git a/drivers/net/ethernet/amd/pcnet32.c b/drivers/net/ethernet/amd/pcnet32.c index 72db9f9e7beea..c6bd803f5b0c1 100644 --- a/drivers/net/ethernet/amd/pcnet32.c +++ b/drivers/net/ethernet/amd/pcnet32.c @@ -462,7 +462,7 @@ static void pcnet32_netif_start(struct net_device *dev) val = lp->a->read_csr(ioaddr, CSR3); val &= 0x00ff; lp->a->write_csr(ioaddr, CSR3, val); - napi_enable(&lp->napi); + napi_enable_locked(&lp->napi); } /* @@ -889,6 +889,7 @@ static int pcnet32_set_ringparam(struct net_device *dev, if (netif_running(dev)) pcnet32_netif_stop(dev); + netdev_lock(dev); spin_lock_irqsave(&lp->lock, flags); lp->a->write_csr(ioaddr, CSR0, CSR0_STOP); /* stop the chip */ @@ -920,6 +921,7 @@ static int pcnet32_set_ringparam(struct net_device *dev, } spin_unlock_irqrestore(&lp->lock, flags); + netdev_unlock(dev); netif_info(lp, drv, dev, "Ring Param Settings: RX: %d, TX: %d\n", lp->rx_ring_size, lp->tx_ring_size); @@ -985,6 +987,7 @@ static int pcnet32_loopback_test(struct net_device *dev, uint64_t * data1) if (netif_running(dev)) pcnet32_netif_stop(dev); + netdev_lock(dev); spin_lock_irqsave(&lp->lock, flags); lp->a->write_csr(ioaddr, CSR0, CSR0_STOP); /* stop the chip */ @@ -1122,6 +1125,7 @@ static int pcnet32_loopback_test(struct net_device *dev, uint64_t * data1) lp->a->write_bcr(ioaddr, 20, 4); /* return to 16bit mode */ } spin_unlock_irqrestore(&lp->lock, flags); + netdev_unlock(dev); return rc; } /* end pcnet32_loopback_test */ @@ -2101,6 +2105,7 @@ static int pcnet32_open(struct net_device *dev) return -EAGAIN; } + netdev_lock(dev); spin_lock_irqsave(&lp->lock, flags); /* Check for a valid station address */ if (!is_valid_ether_addr(dev->dev_addr)) { @@ -2266,7 +2271,7 @@ static int pcnet32_open(struct net_device *dev) goto err_free_ring; } - napi_enable(&lp->napi); + napi_enable_locked(&lp->napi); /* Re-initialize the PCNET32, and start it when done. */ lp->a->write_csr(ioaddr, 1, (lp->init_dma_addr & 0xffff)); @@ -2300,6 +2305,7 @@ static int pcnet32_open(struct net_device *dev) lp->a->read_csr(ioaddr, CSR0)); spin_unlock_irqrestore(&lp->lock, flags); + netdev_unlock(dev); return 0; /* Always succeed */ @@ -2315,6 +2321,7 @@ static int pcnet32_open(struct net_device *dev) err_free_irq: spin_unlock_irqrestore(&lp->lock, flags); + netdev_unlock(dev); free_irq(dev->irq, dev); return rc; } diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c index 7740f446c73f4..cbfaaa5b7d02e 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_main.c +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c @@ -1180,7 +1180,7 @@ static void iavf_napi_enable_all(struct iavf_adapter *adapter) q_vector = &adapter->q_vectors[q_idx]; napi = &q_vector->napi; - napi_enable(napi); + napi_enable_locked(napi); } } @@ -1196,7 +1196,7 @@ static void iavf_napi_disable_all(struct iavf_adapter *adapter) for (q_idx = 0; q_idx < q_vectors; q_idx++) { q_vector = &adapter->q_vectors[q_idx]; - napi_disable(&q_vector->napi); + napi_disable_locked(&q_vector->napi); } } @@ -1800,8 +1800,8 @@ static int iavf_alloc_q_vectors(struct iavf_adapter *adapter) q_vector->v_idx = q_idx; q_vector->reg_idx = q_idx; cpumask_copy(&q_vector->affinity_mask, cpu_possible_mask); - netif_napi_add(adapter->netdev, &q_vector->napi, - iavf_napi_poll); + netif_napi_add_locked(adapter->netdev, &q_vector->napi, + iavf_napi_poll); } return 0; @@ -1827,7 +1827,7 @@ static void iavf_free_q_vectors(struct iavf_adapter *adapter) for (q_idx = 0; q_idx < num_q_vectors; q_idx++) { struct iavf_q_vector *q_vector = &adapter->q_vectors[q_idx]; - netif_napi_del(&q_vector->napi); + netif_napi_del_locked(&q_vector->napi); } kfree(adapter->q_vectors); adapter->q_vectors = NULL; @@ -1977,7 +1977,7 @@ static void iavf_finish_config(struct work_struct *work) * The dev->lock is needed to update the queue number */ rtnl_lock(); - mutex_lock(&adapter->netdev->lock); + netdev_lock(adapter->netdev); mutex_lock(&adapter->crit_lock); if ((adapter->flags & IAVF_FLAG_SETUP_NETDEV_FEATURES) && @@ -1997,7 +1997,7 @@ static void iavf_finish_config(struct work_struct *work) netif_set_real_num_tx_queues(adapter->netdev, pairs); if (adapter->netdev->reg_state != NETREG_REGISTERED) { - mutex_unlock(&adapter->netdev->lock); + netdev_unlock(adapter->netdev); netdev_released = true; err = register_netdevice(adapter->netdev); if (err) { @@ -2027,7 +2027,7 @@ static void iavf_finish_config(struct work_struct *work) out: mutex_unlock(&adapter->crit_lock); if (!netdev_released) - mutex_unlock(&adapter->netdev->lock); + netdev_unlock(adapter->netdev); rtnl_unlock(); } @@ -2724,10 +2724,10 @@ static void iavf_watchdog_task(struct work_struct *work) struct iavf_hw *hw = &adapter->hw; u32 reg_val; - mutex_lock(&netdev->lock); + netdev_lock(netdev); if (!mutex_trylock(&adapter->crit_lock)) { if (adapter->state == __IAVF_REMOVE) { - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return; } @@ -2741,35 +2741,35 @@ static void iavf_watchdog_task(struct work_struct *work) case __IAVF_STARTUP: iavf_startup(adapter); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(30)); return; case __IAVF_INIT_VERSION_CHECK: iavf_init_version_check(adapter); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(30)); return; case __IAVF_INIT_GET_RESOURCES: iavf_init_get_resources(adapter); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(1)); return; case __IAVF_INIT_EXTENDED_CAPS: iavf_init_process_extended_caps(adapter); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(1)); return; case __IAVF_INIT_CONFIG_ADAPTER: iavf_init_config_adapter(adapter); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(1)); return; @@ -2781,7 +2781,7 @@ static void iavf_watchdog_task(struct work_struct *work) * as it can loop forever */ mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return; } if (++adapter->aq_wait_count > IAVF_AQ_MAX_ERR) { @@ -2790,7 +2790,7 @@ static void iavf_watchdog_task(struct work_struct *work) adapter->flags |= IAVF_FLAG_PF_COMMS_FAILED; iavf_shutdown_adminq(hw); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); queue_delayed_work(adapter->wq, &adapter->watchdog_task, (5 * HZ)); return; @@ -2798,7 +2798,7 @@ static void iavf_watchdog_task(struct work_struct *work) /* Try again from failed step*/ iavf_change_state(adapter, adapter->last_state); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); queue_delayed_work(adapter->wq, &adapter->watchdog_task, HZ); return; case __IAVF_COMM_FAILED: @@ -2811,7 +2811,7 @@ static void iavf_watchdog_task(struct work_struct *work) iavf_change_state(adapter, __IAVF_INIT_FAILED); adapter->flags &= ~IAVF_FLAG_PF_COMMS_FAILED; mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return; } reg_val = rd32(hw, IAVF_VFGEN_RSTAT) & @@ -2831,14 +2831,14 @@ static void iavf_watchdog_task(struct work_struct *work) adapter->aq_required = 0; adapter->current_op = VIRTCHNL_OP_UNKNOWN; mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); queue_delayed_work(adapter->wq, &adapter->watchdog_task, msecs_to_jiffies(10)); return; case __IAVF_RESETTING: mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); queue_delayed_work(adapter->wq, &adapter->watchdog_task, HZ * 2); return; @@ -2869,7 +2869,7 @@ static void iavf_watchdog_task(struct work_struct *work) case __IAVF_REMOVE: default: mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return; } @@ -2881,14 +2881,14 @@ static void iavf_watchdog_task(struct work_struct *work) dev_err(&adapter->pdev->dev, "Hardware reset detected\n"); iavf_schedule_reset(adapter, IAVF_FLAG_RESET_PENDING); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); queue_delayed_work(adapter->wq, &adapter->watchdog_task, HZ * 2); return; } mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); restart_watchdog: if (adapter->state >= __IAVF_DOWN) queue_work(adapter->wq, &adapter->adminq_task); @@ -3015,12 +3015,12 @@ static void iavf_reset_task(struct work_struct *work) /* When device is being removed it doesn't make sense to run the reset * task, just return in such a case. */ - mutex_lock(&netdev->lock); + netdev_lock(netdev); if (!mutex_trylock(&adapter->crit_lock)) { if (adapter->state != __IAVF_REMOVE) queue_work(adapter->wq, &adapter->reset_task); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return; } @@ -3068,7 +3068,7 @@ static void iavf_reset_task(struct work_struct *work) reg_val); iavf_disable_vf(adapter); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return; /* Do not attempt to reinit. It's dead, Jim. */ } @@ -3209,7 +3209,7 @@ static void iavf_reset_task(struct work_struct *work) wake_up(&adapter->reset_waitqueue); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return; reset_err: @@ -3220,7 +3220,7 @@ static void iavf_reset_task(struct work_struct *work) iavf_disable_vf(adapter); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); dev_err(&adapter->pdev->dev, "failed to allocate resources during reinit\n"); } @@ -3692,10 +3692,10 @@ static int __iavf_setup_tc(struct net_device *netdev, void *type_data) if (test_bit(__IAVF_IN_REMOVE_TASK, &adapter->crit_section)) return 0; - mutex_lock(&netdev->lock); + netdev_lock(netdev); netif_set_real_num_rx_queues(netdev, total_qps); netif_set_real_num_tx_queues(netdev, total_qps); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return ret; } @@ -4365,7 +4365,7 @@ static int iavf_open(struct net_device *netdev) return -EIO; } - mutex_lock(&netdev->lock); + netdev_lock(netdev); while (!mutex_trylock(&adapter->crit_lock)) { /* If we are in __IAVF_INIT_CONFIG_ADAPTER state the crit_lock * is already taken and iavf_open is called from an upper @@ -4373,7 +4373,7 @@ static int iavf_open(struct net_device *netdev) * We have to leave here to avoid dead lock. */ if (adapter->state == __IAVF_INIT_CONFIG_ADAPTER) { - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return -EBUSY; } @@ -4424,7 +4424,7 @@ static int iavf_open(struct net_device *netdev) iavf_irq_enable(adapter, true); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return 0; @@ -4437,7 +4437,7 @@ static int iavf_open(struct net_device *netdev) iavf_free_all_tx_resources(adapter); err_unlock: mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return err; } @@ -4459,12 +4459,12 @@ static int iavf_close(struct net_device *netdev) u64 aq_to_restore; int status; - mutex_lock(&netdev->lock); + netdev_lock(netdev); mutex_lock(&adapter->crit_lock); if (adapter->state <= __IAVF_DOWN_PENDING) { mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return 0; } @@ -4498,7 +4498,7 @@ static int iavf_close(struct net_device *netdev) iavf_free_traffic_irqs(adapter); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); /* We explicitly don't free resources here because the hardware is * still active and can DMA into memory. Resources are cleared in @@ -5375,7 +5375,7 @@ static int iavf_suspend(struct device *dev_d) netif_device_detach(netdev); - mutex_lock(&netdev->lock); + netdev_lock(netdev); mutex_lock(&adapter->crit_lock); if (netif_running(netdev)) { @@ -5387,7 +5387,7 @@ static int iavf_suspend(struct device *dev_d) iavf_reset_interrupt_capability(adapter); mutex_unlock(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); return 0; } @@ -5486,7 +5486,7 @@ static void iavf_remove(struct pci_dev *pdev) if (netdev->reg_state == NETREG_REGISTERED) unregister_netdev(netdev); - mutex_lock(&netdev->lock); + netdev_lock(netdev); mutex_lock(&adapter->crit_lock); dev_info(&adapter->pdev->dev, "Removing device\n"); iavf_change_state(adapter, __IAVF_REMOVE); @@ -5523,7 +5523,7 @@ static void iavf_remove(struct pci_dev *pdev) mutex_destroy(&hw->aq.asq_mutex); mutex_unlock(&adapter->crit_lock); mutex_destroy(&adapter->crit_lock); - mutex_unlock(&netdev->lock); + netdev_unlock(netdev); iounmap(hw->hw_addr); pci_release_regions(pdev); diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index 9e79a60baebc9..aa049cee576da 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -4392,6 +4392,7 @@ static int mvneta_cpu_online(unsigned int cpu, struct hlist_node *node) if (pp->neta_armada3700) return 0; + netdev_lock(port->napi.dev); spin_lock(&pp->lock); /* * Configuring the driver for a new CPU while the driver is @@ -4418,7 +4419,7 @@ static int mvneta_cpu_online(unsigned int cpu, struct hlist_node *node) /* Mask all ethernet port interrupts */ on_each_cpu(mvneta_percpu_mask_interrupt, pp, true); - napi_enable(&port->napi); + napi_enable_locked(&port->napi); /* * Enable per-CPU interrupts on the CPU that is @@ -4439,6 +4440,8 @@ static int mvneta_cpu_online(unsigned int cpu, struct hlist_node *node) MVNETA_CAUSE_LINK_CHANGE); netif_tx_start_all_queues(pp->dev); spin_unlock(&pp->lock); + netdev_unlock(port->napi.dev); + return 0; } diff --git a/drivers/net/ethernet/via/via-velocity.c b/drivers/net/ethernet/via/via-velocity.c index dd4a07c97eeeb..5aa93144a4f5a 100644 --- a/drivers/net/ethernet/via/via-velocity.c +++ b/drivers/net/ethernet/via/via-velocity.c @@ -2320,7 +2320,8 @@ static int velocity_change_mtu(struct net_device *dev, int new_mtu) if (ret < 0) goto out_free_tmp_vptr_1; - napi_disable(&vptr->napi); + netdev_lock(dev); + napi_disable_locked(&vptr->napi); spin_lock_irqsave(&vptr->lock, flags); @@ -2342,12 +2343,13 @@ static int velocity_change_mtu(struct net_device *dev, int new_mtu) velocity_give_many_rx_descs(vptr); - napi_enable(&vptr->napi); + napi_enable_locked(&vptr->napi); mac_enable_int(vptr->mac_regs); netif_start_queue(dev); spin_unlock_irqrestore(&vptr->lock, flags); + netdev_unlock(dev); velocity_free_rings(tmp_vptr); diff --git a/drivers/net/netdevsim/ethtool.c b/drivers/net/netdevsim/ethtool.c index 9e0df40c71e18..12163635b759f 100644 --- a/drivers/net/netdevsim/ethtool.c +++ b/drivers/net/netdevsim/ethtool.c @@ -108,10 +108,10 @@ nsim_set_channels(struct net_device *dev, struct ethtool_channels *ch) struct netdevsim *ns = netdev_priv(dev); int err; - mutex_lock(&dev->lock); + netdev_lock(dev); err = netif_set_real_num_queues(dev, ch->combined_count, ch->combined_count); - mutex_unlock(&dev->lock); + netdev_unlock(dev); if (err) return err; diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 3e6336775baf0..8308d9c75918f 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -382,8 +382,9 @@ struct napi_struct { struct sk_buff *skb; struct list_head rx_list; /* Pending GRO_NORMAL skbs */ int rx_count; /* length of rx_list */ - unsigned int napi_id; + unsigned int napi_id; /* protected by netdev_lock */ struct hrtimer timer; + /* all fields past this point are write-protected by netdev_lock */ struct task_struct *thread; unsigned long gro_flush_timeout; unsigned long irq_suspend_timeout; @@ -570,16 +571,11 @@ static inline bool napi_complete(struct napi_struct *n) int dev_set_threaded(struct net_device *dev, bool threaded); -/** - * napi_disable - prevent NAPI from scheduling - * @n: NAPI context - * - * Stop NAPI from being scheduled on this context. - * Waits till any outstanding processing completes. - */ void napi_disable(struct napi_struct *n); +void napi_disable_locked(struct napi_struct *n); void napi_enable(struct napi_struct *n); +void napi_enable_locked(struct napi_struct *n); /** * napi_synchronize - wait until NAPI is not running @@ -2444,8 +2440,27 @@ struct net_device { u32 napi_defer_hard_irqs; /** - * @lock: protects @net_shaper_hierarchy, feel free to use for other - * netdev-scope protection. Ordering: take after rtnl_lock. + * @up: copy of @state's IFF_UP, but safe to read with just @lock. + * May report false negatives while the device is being opened + * or closed (@lock does not protect .ndo_open, or .ndo_close). + */ + bool up; + + /** + * @lock: netdev-scope lock, protects a small selection of fields. + * Should always be taken using netdev_lock() / netdev_unlock() helpers. + * Drivers are free to use it for other protection. + * + * Protects: + * @gro_flush_timeout, @napi_defer_hard_irqs, @napi_list, + * @net_shaper_hierarchy, @reg_state, @threaded + * + * Partially protects (writers must hold both @lock and rtnl_lock): + * @up + * + * Also protects some fields in struct napi_struct. + * + * Ordering: take after rtnl_lock. */ struct mutex lock; @@ -2671,18 +2686,58 @@ void netif_queue_set_napi(struct net_device *dev, unsigned int queue_index, enum netdev_queue_type type, struct napi_struct *napi); -static inline void netif_napi_set_irq(struct napi_struct *napi, int irq) +static inline void netdev_lock(struct net_device *dev) +{ + mutex_lock(&dev->lock); +} + +static inline void netdev_unlock(struct net_device *dev) +{ + mutex_unlock(&dev->lock); +} + +static inline void netdev_assert_locked(struct net_device *dev) +{ + lockdep_assert_held(&dev->lock); +} + +static inline void netdev_assert_locked_or_invisible(struct net_device *dev) +{ + if (dev->reg_state == NETREG_REGISTERED || + dev->reg_state == NETREG_UNREGISTERING) + netdev_assert_locked(dev); +} + +static inline void netif_napi_set_irq_locked(struct napi_struct *napi, int irq) { napi->irq = irq; } +static inline void netif_napi_set_irq(struct napi_struct *napi, int irq) +{ + netdev_lock(napi->dev); + netif_napi_set_irq_locked(napi, irq); + netdev_unlock(napi->dev); +} + /* Default NAPI poll() weight * Device drivers are strongly advised to not use bigger value */ #define NAPI_POLL_WEIGHT 64 -void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, - int (*poll)(struct napi_struct *, int), int weight); +void netif_napi_add_weight_locked(struct net_device *dev, + struct napi_struct *napi, + int (*poll)(struct napi_struct *, int), + int weight); + +static inline void +netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, + int (*poll)(struct napi_struct *, int), int weight) +{ + netdev_lock(dev); + netif_napi_add_weight_locked(dev, napi, poll, weight); + netdev_unlock(dev); +} /** * netif_napi_add() - initialize a NAPI context @@ -2700,6 +2755,13 @@ netif_napi_add(struct net_device *dev, struct napi_struct *napi, netif_napi_add_weight(dev, napi, poll, NAPI_POLL_WEIGHT); } +static inline void +netif_napi_add_locked(struct net_device *dev, struct napi_struct *napi, + int (*poll)(struct napi_struct *, int)) +{ + netif_napi_add_weight_locked(dev, napi, poll, NAPI_POLL_WEIGHT); +} + static inline void netif_napi_add_tx_weight(struct net_device *dev, struct napi_struct *napi, @@ -2710,6 +2772,15 @@ netif_napi_add_tx_weight(struct net_device *dev, netif_napi_add_weight(dev, napi, poll, weight); } +static inline void +netif_napi_add_config_locked(struct net_device *dev, struct napi_struct *napi, + int (*poll)(struct napi_struct *, int), int index) +{ + napi->index = index; + napi->config = &dev->napi_config[index]; + netif_napi_add_weight_locked(dev, napi, poll, NAPI_POLL_WEIGHT); +} + /** * netif_napi_add_config - initialize a NAPI context with persistent config * @dev: network device @@ -2721,9 +2792,9 @@ static inline void netif_napi_add_config(struct net_device *dev, struct napi_struct *napi, int (*poll)(struct napi_struct *, int), int index) { - napi->index = index; - napi->config = &dev->napi_config[index]; - netif_napi_add_weight(dev, napi, poll, NAPI_POLL_WEIGHT); + netdev_lock(dev); + netif_napi_add_config_locked(dev, napi, poll, index); + netdev_unlock(dev); } /** @@ -2743,6 +2814,8 @@ static inline void netif_napi_add_tx(struct net_device *dev, netif_napi_add_tx_weight(dev, napi, poll, NAPI_POLL_WEIGHT); } +void __netif_napi_del_locked(struct napi_struct *napi); + /** * __netif_napi_del - remove a NAPI context * @napi: NAPI context @@ -2751,7 +2824,18 @@ static inline void netif_napi_add_tx(struct net_device *dev, * containing @napi. Drivers might want to call this helper to combine * all the needed RCU grace periods into a single one. */ -void __netif_napi_del(struct napi_struct *napi); +static inline void __netif_napi_del(struct napi_struct *napi) +{ + netdev_lock(napi->dev); + __netif_napi_del_locked(napi); + netdev_unlock(napi->dev); +} + +static inline void netif_napi_del_locked(struct napi_struct *napi) +{ + __netif_napi_del_locked(napi); + synchronize_net(); +} /** * netif_napi_del - remove a NAPI context diff --git a/net/core/dev.c b/net/core/dev.c index 47e6b0f73cfc7..b6722ed9767a9 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -768,7 +768,8 @@ static struct napi_struct *napi_by_id(unsigned int napi_id) } /* must be called under rcu_read_lock(), as we dont take a reference */ -struct napi_struct *netdev_napi_by_id(struct net *net, unsigned int napi_id) +static struct napi_struct * +netdev_napi_by_id(struct net *net, unsigned int napi_id) { struct napi_struct *napi; @@ -784,6 +785,49 @@ struct napi_struct *netdev_napi_by_id(struct net *net, unsigned int napi_id) return napi; } +/** + * netdev_napi_by_id_lock() - find a device by NAPI ID and lock it + * @net: the applicable net namespace + * @napi_id: ID of a NAPI of a target device + * + * Find a NAPI instance with @napi_id. Lock its device. + * The device must be in %NETREG_REGISTERED state for lookup to succeed. + * netdev_unlock() must be called to release it. + * + * Return: pointer to NAPI, its device with lock held, NULL if not found. + */ +struct napi_struct * +netdev_napi_by_id_lock(struct net *net, unsigned int napi_id) +{ + struct napi_struct *napi; + struct net_device *dev; + + rcu_read_lock(); + napi = netdev_napi_by_id(net, napi_id); + if (!napi || READ_ONCE(napi->dev->reg_state) != NETREG_REGISTERED) { + rcu_read_unlock(); + return NULL; + } + + dev = napi->dev; + dev_hold(dev); + rcu_read_unlock(); + + dev = __netdev_put_lock(dev); + if (!dev) + return NULL; + + rcu_read_lock(); + napi = netdev_napi_by_id(net, napi_id); + if (napi && napi->dev != dev) + napi = NULL; + rcu_read_unlock(); + + if (!napi) + netdev_unlock(dev); + return napi; +} + /** * __dev_get_by_name - find a device by its name * @net: the applicable net namespace @@ -972,6 +1016,73 @@ struct net_device *dev_get_by_napi_id(unsigned int napi_id) return napi ? napi->dev : NULL; } +/* Release the held reference on the net_device, and if the net_device + * is still registered try to lock the instance lock. If device is being + * unregistered NULL will be returned (but the reference has been released, + * either way!) + * + * This helper is intended for locking net_device after it has been looked up + * using a lockless lookup helper. Lock prevents the instance from going away. + */ +struct net_device *__netdev_put_lock(struct net_device *dev) +{ + netdev_lock(dev); + if (dev->reg_state > NETREG_REGISTERED) { + netdev_unlock(dev); + dev_put(dev); + return NULL; + } + dev_put(dev); + return dev; +} + +/** + * netdev_get_by_index_lock() - find a device by its ifindex + * @net: the applicable net namespace + * @ifindex: index of device + * + * Search for an interface by index. If a valid device + * with @ifindex is found it will be returned with netdev->lock held. + * netdev_unlock() must be called to release it. + * + * Return: pointer to a device with lock held, NULL if not found. + */ +struct net_device *netdev_get_by_index_lock(struct net *net, int ifindex) +{ + struct net_device *dev; + + dev = dev_get_by_index(net, ifindex); + if (!dev) + return NULL; + + return __netdev_put_lock(dev); +} + +struct net_device * +netdev_xa_find_lock(struct net *net, struct net_device *dev, + unsigned long *index) +{ + if (dev) + netdev_unlock(dev); + + do { + rcu_read_lock(); + dev = xa_find(&net->dev_by_index, index, ULONG_MAX, XA_PRESENT); + if (!dev) { + rcu_read_unlock(); + return NULL; + } + dev_hold(dev); + rcu_read_unlock(); + + dev = __netdev_put_lock(dev); + if (dev) + return dev; + + (*index)++; + } while (true); +} + static DEFINE_SEQLOCK(netdev_rename_lock); void netdev_copy_name(struct net_device *dev, char *name) @@ -1509,7 +1620,7 @@ static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack) if (ret) clear_bit(__LINK_STATE_START, &dev->state); else { - dev->flags |= IFF_UP; + netif_set_up(dev, true); dev_set_rx_mode(dev); dev_activate(dev); add_device_randomness(dev->dev_addr, dev->addr_len); @@ -1588,7 +1699,7 @@ static void __dev_close_many(struct list_head *head) if (ops->ndo_stop) ops->ndo_stop(dev); - dev->flags &= ~IFF_UP; + netif_set_up(dev, false); netpoll_poll_enable(dev); } } @@ -6674,6 +6785,8 @@ int dev_set_threaded(struct net_device *dev, bool threaded) struct napi_struct *napi; int err = 0; + netdev_assert_locked_or_invisible(dev); + if (dev->threaded == threaded) return 0; @@ -6800,9 +6913,12 @@ netif_napi_dev_list_add(struct net_device *dev, struct napi_struct *napi) list_add_rcu(&napi->dev_list, higher); /* adds after higher */ } -void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, - int (*poll)(struct napi_struct *, int), int weight) +void netif_napi_add_weight_locked(struct net_device *dev, + struct napi_struct *napi, + int (*poll)(struct napi_struct *, int), + int weight) { + netdev_assert_locked(dev); if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state))) return; @@ -6841,15 +6957,17 @@ void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, */ if (dev->threaded && napi_kthread_create(napi)) dev->threaded = false; - netif_napi_set_irq(napi, -1); + netif_napi_set_irq_locked(napi, -1); } -EXPORT_SYMBOL(netif_napi_add_weight); +EXPORT_SYMBOL(netif_napi_add_weight_locked); -void napi_disable(struct napi_struct *n) +void napi_disable_locked(struct napi_struct *n) { unsigned long val, new; might_sleep(); + netdev_assert_locked(n->dev); + set_bit(NAPI_STATE_DISABLE, &n->state); val = READ_ONCE(n->state); @@ -6872,16 +6990,25 @@ void napi_disable(struct napi_struct *n) clear_bit(NAPI_STATE_DISABLE, &n->state); } -EXPORT_SYMBOL(napi_disable); +EXPORT_SYMBOL(napi_disable_locked); /** - * napi_enable - enable NAPI scheduling - * @n: NAPI context + * napi_disable() - prevent NAPI from scheduling + * @n: NAPI context * - * Resume NAPI from being scheduled on this context. - * Must be paired with napi_disable. + * Stop NAPI from being scheduled on this context. + * Waits till any outstanding processing completes. + * Takes netdev_lock() for associated net_device. */ -void napi_enable(struct napi_struct *n) +void napi_disable(struct napi_struct *n) +{ + netdev_lock(n->dev); + napi_disable_locked(n); + netdev_unlock(n->dev); +} +EXPORT_SYMBOL(napi_disable); + +void napi_enable_locked(struct napi_struct *n) { unsigned long new, val = READ_ONCE(n->state); @@ -6898,6 +7025,22 @@ void napi_enable(struct napi_struct *n) new |= NAPIF_STATE_THREADED; } while (!try_cmpxchg(&n->state, &val, new)); } +EXPORT_SYMBOL(napi_enable_locked); + +/** + * napi_enable() - enable NAPI scheduling + * @n: NAPI context + * + * Enable scheduling of a NAPI instance. + * Must be paired with napi_disable(). + * Takes netdev_lock() for associated net_device. + */ +void napi_enable(struct napi_struct *n) +{ + netdev_lock(n->dev); + napi_enable_locked(n); + netdev_unlock(n->dev); +} EXPORT_SYMBOL(napi_enable); static void flush_gro_hash(struct napi_struct *napi) @@ -6914,8 +7057,10 @@ static void flush_gro_hash(struct napi_struct *napi) } /* Must be called in process context */ -void __netif_napi_del(struct napi_struct *napi) +void __netif_napi_del_locked(struct napi_struct *napi) { + netdev_assert_locked(napi->dev); + if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state)) return; @@ -6935,7 +7080,7 @@ void __netif_napi_del(struct napi_struct *napi) napi->thread = NULL; } } -EXPORT_SYMBOL(__netif_napi_del); +EXPORT_SYMBOL(__netif_napi_del_locked); static int __napi_poll(struct napi_struct *n, bool *repoll) { @@ -10695,7 +10840,9 @@ int register_netdevice(struct net_device *dev) ret = netdev_register_kobject(dev); + netdev_lock(dev); WRITE_ONCE(dev->reg_state, ret ? NETREG_UNREGISTERED : NETREG_REGISTERED); + netdev_unlock(dev); if (ret) goto err_uninit_notify; @@ -10969,7 +11116,9 @@ void netdev_run_todo(void) continue; } + netdev_lock(dev); WRITE_ONCE(dev->reg_state, NETREG_UNREGISTERED); + netdev_unlock(dev); linkwatch_sync_dev(dev); } @@ -11575,7 +11724,9 @@ void unregister_netdevice_many_notify(struct list_head *head, list_for_each_entry(dev, head, unreg_list) { /* And unlink it from device chain. */ unlist_netdevice(dev); + netdev_lock(dev); WRITE_ONCE(dev->reg_state, NETREG_UNREGISTERING); + netdev_unlock(dev); } flush_all_backlogs(); diff --git a/net/core/dev.h b/net/core/dev.h index d8966847794ce..a5b166bbd169a 100644 --- a/net/core/dev.h +++ b/net/core/dev.h @@ -2,6 +2,7 @@ #ifndef _NET_CORE_DEV_H #define _NET_CORE_DEV_H +#include #include #include #include @@ -22,9 +23,23 @@ struct sd_flow_limit { extern int netdev_flow_limit_table_len; -struct napi_struct *netdev_napi_by_id(struct net *net, unsigned int napi_id); +struct napi_struct * +netdev_napi_by_id_lock(struct net *net, unsigned int napi_id); struct net_device *dev_get_by_napi_id(unsigned int napi_id); +struct net_device *netdev_get_by_index_lock(struct net *net, int ifindex); +struct net_device *__netdev_put_lock(struct net_device *dev); +struct net_device * +netdev_xa_find_lock(struct net *net, struct net_device *dev, + unsigned long *index); + +DEFINE_FREE(netdev_unlock, struct net_device *, if (_T) netdev_unlock(_T)); + +#define for_each_netdev_lock_scoped(net, var_name, ifindex) \ + for (struct net_device *var_name __free(netdev_unlock) = NULL; \ + (var_name = netdev_xa_find_lock(net, var_name, &ifindex)); \ + ifindex++) + #ifdef CONFIG_PROC_FS int __init dev_proc_init(void); #else @@ -112,6 +127,18 @@ void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, void unregister_netdevice_many_notify(struct list_head *head, u32 portid, const struct nlmsghdr *nlh); +static inline void netif_set_up(struct net_device *dev, bool value) +{ + if (value) + dev->flags |= IFF_UP; + else + dev->flags &= ~IFF_UP; + + netdev_lock(dev); + dev->up = value; + netdev_unlock(dev); +} + static inline void netif_set_gso_max_size(struct net_device *dev, unsigned int size) { diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 2d9afc6e2161e..07cb99b114bdd 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -36,7 +36,7 @@ static const char fmt_uint[] = "%u\n"; static const char fmt_ulong[] = "%lu\n"; static const char fmt_u64[] = "%llu\n"; -/* Caller holds RTNL or RCU */ +/* Caller holds RTNL, netdev->lock or RCU */ static inline int dev_isalive(const struct net_device *dev) { return READ_ONCE(dev->reg_state) <= NETREG_REGISTERED; @@ -108,6 +108,36 @@ static ssize_t netdev_store(struct device *dev, struct device_attribute *attr, return ret; } +/* Same as netdev_store() but takes netdev_lock() instead of rtnl_lock() */ +static ssize_t +netdev_lock_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len, + int (*set)(struct net_device *, unsigned long)) +{ + struct net_device *netdev = to_net_dev(dev); + struct net *net = dev_net(netdev); + unsigned long new; + int ret; + + if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) + return -EPERM; + + ret = kstrtoul(buf, 0, &new); + if (ret) + return ret; + + netdev_lock(netdev); + + if (dev_isalive(netdev)) { + ret = (*set)(netdev, new); + if (ret == 0) + ret = len; + } + netdev_unlock(netdev); + + return ret; +} + NETDEVICE_SHOW_RO(dev_id, fmt_hex); NETDEVICE_SHOW_RO(dev_port, fmt_dec); NETDEVICE_SHOW_RO(addr_assign_type, fmt_dec); @@ -420,7 +450,7 @@ static ssize_t gro_flush_timeout_store(struct device *dev, if (!capable(CAP_NET_ADMIN)) return -EPERM; - return netdev_store(dev, attr, buf, len, change_gro_flush_timeout); + return netdev_lock_store(dev, attr, buf, len, change_gro_flush_timeout); } NETDEVICE_SHOW_RW(gro_flush_timeout, fmt_ulong); @@ -440,7 +470,8 @@ static ssize_t napi_defer_hard_irqs_store(struct device *dev, if (!capable(CAP_NET_ADMIN)) return -EPERM; - return netdev_store(dev, attr, buf, len, change_napi_defer_hard_irqs); + return netdev_lock_store(dev, attr, buf, len, + change_napi_defer_hard_irqs); } NETDEVICE_SHOW_RW(napi_defer_hard_irqs, fmt_uint); @@ -638,7 +669,7 @@ static ssize_t threaded_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { - return netdev_store(dev, attr, buf, len, modify_napi_threaded); + return netdev_lock_store(dev, attr, buf, len, modify_napi_threaded); } static DEVICE_ATTR_RW(threaded); diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c index c59619a2ec236..715f85c6b62ea 100644 --- a/net/core/netdev-genl.c +++ b/net/core/netdev-genl.c @@ -167,7 +167,7 @@ netdev_nl_napi_fill_one(struct sk_buff *rsp, struct napi_struct *napi, void *hdr; pid_t pid; - if (!(napi->dev->flags & IFF_UP)) + if (!napi->dev->up) return 0; hdr = genlmsg_iput(rsp, info); @@ -229,20 +229,15 @@ int netdev_nl_napi_get_doit(struct sk_buff *skb, struct genl_info *info) if (!rsp) return -ENOMEM; - rtnl_lock(); - rcu_read_lock(); - - napi = netdev_napi_by_id(genl_info_net(info), napi_id); + napi = netdev_napi_by_id_lock(genl_info_net(info), napi_id); if (napi) { err = netdev_nl_napi_fill_one(rsp, napi, info); + netdev_unlock(napi->dev); } else { NL_SET_BAD_ATTR(info->extack, info->attrs[NETDEV_A_NAPI_ID]); err = -ENOENT; } - rcu_read_unlock(); - rtnl_unlock(); - if (err) { goto err_free_msg; } else if (!rsp->len) { @@ -266,7 +261,7 @@ netdev_nl_napi_dump_one(struct net_device *netdev, struct sk_buff *rsp, unsigned int prev_id; int err = 0; - if (!(netdev->flags & IFF_UP)) + if (!netdev->up) return err; prev_id = UINT_MAX; @@ -301,22 +296,22 @@ int netdev_nl_napi_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb) if (info->attrs[NETDEV_A_NAPI_IFINDEX]) ifindex = nla_get_u32(info->attrs[NETDEV_A_NAPI_IFINDEX]); - rtnl_lock(); if (ifindex) { - netdev = __dev_get_by_index(net, ifindex); - if (netdev) + netdev = netdev_get_by_index_lock(net, ifindex); + if (netdev) { err = netdev_nl_napi_dump_one(netdev, skb, info, ctx); - else + netdev_unlock(netdev); + } else { err = -ENODEV; + } } else { - for_each_netdev_dump(net, netdev, ctx->ifindex) { + for_each_netdev_lock_scoped(net, netdev, ctx->ifindex) { err = netdev_nl_napi_dump_one(netdev, skb, info, ctx); if (err < 0) break; ctx->napi_id = 0; } } - rtnl_unlock(); return err; } @@ -357,20 +352,15 @@ int netdev_nl_napi_set_doit(struct sk_buff *skb, struct genl_info *info) napi_id = nla_get_u32(info->attrs[NETDEV_A_NAPI_ID]); - rtnl_lock(); - rcu_read_lock(); - - napi = netdev_napi_by_id(genl_info_net(info), napi_id); + napi = netdev_napi_by_id_lock(genl_info_net(info), napi_id); if (napi) { err = netdev_nl_napi_set_config(napi, info); + netdev_unlock(napi->dev); } else { NL_SET_BAD_ATTR(info->extack, info->attrs[NETDEV_A_NAPI_ID]); err = -ENOENT; } - rcu_read_unlock(); - rtnl_unlock(); - return err; } @@ -442,7 +432,7 @@ netdev_nl_queue_fill(struct sk_buff *rsp, struct net_device *netdev, u32 q_idx, { int err; - if (!(netdev->flags & IFF_UP)) + if (!netdev->up) return -ENOENT; err = netdev_nl_queue_validate(netdev, q_idx, q_type); @@ -474,11 +464,13 @@ int netdev_nl_queue_get_doit(struct sk_buff *skb, struct genl_info *info) rtnl_lock(); - netdev = __dev_get_by_index(genl_info_net(info), ifindex); - if (netdev) + netdev = netdev_get_by_index_lock(genl_info_net(info), ifindex); + if (netdev) { err = netdev_nl_queue_fill(rsp, netdev, q_id, q_type, info); - else + netdev_unlock(netdev); + } else { err = -ENODEV; + } rtnl_unlock(); @@ -499,7 +491,7 @@ netdev_nl_queue_dump_one(struct net_device *netdev, struct sk_buff *rsp, { int err = 0; - if (!(netdev->flags & IFF_UP)) + if (!netdev->up) return err; for (; ctx->rxq_idx < netdev->real_num_rx_queues; ctx->rxq_idx++) { @@ -532,13 +524,15 @@ int netdev_nl_queue_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb) rtnl_lock(); if (ifindex) { - netdev = __dev_get_by_index(net, ifindex); - if (netdev) + netdev = netdev_get_by_index_lock(net, ifindex); + if (netdev) { err = netdev_nl_queue_dump_one(netdev, skb, info, ctx); - else + netdev_unlock(netdev); + } else { err = -ENODEV; + } } else { - for_each_netdev_dump(net, netdev, ctx->ifindex) { + for_each_netdev_lock_scoped(net, netdev, ctx->ifindex) { err = netdev_nl_queue_dump_one(netdev, skb, info, ctx); if (err < 0) break; diff --git a/net/shaper/shaper.c b/net/shaper/shaper.c index 15463062fe7b6..7101a48bce545 100644 --- a/net/shaper/shaper.c +++ b/net/shaper/shaper.c @@ -40,7 +40,7 @@ static void net_shaper_lock(struct net_shaper_binding *binding) { switch (binding->type) { case NET_SHAPER_BINDING_TYPE_NETDEV: - mutex_lock(&binding->netdev->lock); + netdev_lock(binding->netdev); break; } } @@ -49,7 +49,7 @@ static void net_shaper_unlock(struct net_shaper_binding *binding) { switch (binding->type) { case NET_SHAPER_BINDING_TYPE_NETDEV: - mutex_unlock(&binding->netdev->lock); + netdev_unlock(binding->netdev); break; } } @@ -1398,7 +1398,7 @@ void net_shaper_set_real_num_tx_queues(struct net_device *dev, /* Only drivers implementing shapers support ensure * the lock is acquired in advance. */ - lockdep_assert_held(&dev->lock); + netdev_assert_locked(dev); /* Take action only when decreasing the tx queue number. */ for (i = txq; i < dev->real_num_tx_queues; ++i) {