diff options
Diffstat (limited to 'drivers/usb')
-rw-r--r-- | drivers/usb/usbip/stub_dev.c | 3 | ||||
-rw-r--r-- | drivers/usb/usbip/usbip_common.c | 7 | ||||
-rw-r--r-- | drivers/usb/usbip/usbip_common.h | 4 | ||||
-rw-r--r-- | drivers/usb/usbip/usbip_event.c | 168 |
4 files changed, 137 insertions, 45 deletions
diff --git a/drivers/usb/usbip/stub_dev.c b/drivers/usb/usbip/stub_dev.c index a3ec49bdc1e6..e286346041f6 100644 --- a/drivers/usb/usbip/stub_dev.c +++ b/drivers/usb/usbip/stub_dev.c @@ -388,7 +388,6 @@ err_files: err_port: dev_set_drvdata(&udev->dev, NULL); usb_put_dev(udev); - kthread_stop_put(sdev->ud.eh); busid_priv->sdev = NULL; stub_device_free(sdev); @@ -449,7 +448,7 @@ static void stub_disconnect(struct usb_device *udev) } /* If usb reset is called from event handler */ - if (busid_priv->sdev->ud.eh == current) + if (usbip_in_eh(current)) return; /* shutdown the current connection */ diff --git a/drivers/usb/usbip/usbip_common.c b/drivers/usb/usbip/usbip_common.c index e40da7759a0e..2e5cf6392a8e 100644 --- a/drivers/usb/usbip/usbip_common.c +++ b/drivers/usb/usbip/usbip_common.c @@ -769,12 +769,19 @@ EXPORT_SYMBOL_GPL(usbip_recv_xbuff); static int __init usbip_core_init(void) { + int ret; + pr_info(DRIVER_DESC " v" USBIP_VERSION "\n"); + ret = usbip_init_eh(); + if (ret) + return ret; + return 0; } static void __exit usbip_core_exit(void) { + usbip_finish_eh(); return; } diff --git a/drivers/usb/usbip/usbip_common.h b/drivers/usb/usbip/usbip_common.h index 86b08475c254..2fbbc643b888 100644 --- a/drivers/usb/usbip/usbip_common.h +++ b/drivers/usb/usbip/usbip_common.h @@ -267,7 +267,6 @@ struct usbip_device { struct task_struct *tcp_tx; unsigned long event; - struct task_struct *eh; wait_queue_head_t eh_waitq; struct eh_ops { @@ -313,10 +312,13 @@ void usbip_pad_iso(struct usbip_device *ud, struct urb *urb); int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb); /* usbip_event.c */ +int usbip_init_eh(void); +void usbip_finish_eh(void); int usbip_start_eh(struct usbip_device *ud); void usbip_stop_eh(struct usbip_device *ud); void usbip_event_add(struct usbip_device *ud, unsigned long event); int usbip_event_happened(struct usbip_device *ud); +int usbip_in_eh(struct task_struct *task); static inline int interface_to_busnum(struct usb_interface *interface) { diff --git a/drivers/usb/usbip/usbip_event.c b/drivers/usb/usbip/usbip_event.c index 2580a32bcdff..f1635662c299 100644 --- a/drivers/usb/usbip/usbip_event.c +++ b/drivers/usb/usbip/usbip_event.c @@ -1,5 +1,6 @@ /* * Copyright (C) 2003-2008 Takahiro Hirofuchi + * Copyright (C) 2015 Nobuo Iwata * * This is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -19,17 +20,68 @@ #include <linux/kthread.h> #include <linux/export.h> +#include <linux/slab.h> +#include <linux/workqueue.h> #include "usbip_common.h" -static int event_handler(struct usbip_device *ud) +struct usbip_event { + struct list_head node; + struct usbip_device *ud; +}; + +static DEFINE_SPINLOCK(event_lock); +static LIST_HEAD(event_list); + +static void set_event(struct usbip_device *ud, unsigned long event) { - usbip_dbg_eh("enter\n"); + unsigned long flags; - /* - * Events are handled by only this thread. - */ - while (usbip_event_happened(ud)) { + spin_lock_irqsave(&ud->lock, flags); + ud->event |= event; + spin_unlock_irqrestore(&ud->lock, flags); +} + +static void unset_event(struct usbip_device *ud, unsigned long event) +{ + unsigned long flags; + + spin_lock_irqsave(&ud->lock, flags); + ud->event &= ~event; + spin_unlock_irqrestore(&ud->lock, flags); +} + +static struct usbip_device *get_event(void) +{ + struct usbip_event *ue = NULL; + struct usbip_device *ud = NULL; + unsigned long flags; + + spin_lock_irqsave(&event_lock, flags); + if (!list_empty(&event_list)) { + ue = list_first_entry(&event_list, struct usbip_event, node); + list_del(&ue->node); + } + spin_unlock_irqrestore(&event_lock, flags); + + if (ue) { + ud = ue->ud; + kfree(ue); + } + return ud; +} + +static struct task_struct *worker_context; + +static void event_handler(struct work_struct *work) +{ + struct usbip_device *ud; + + if (worker_context == NULL) { + worker_context = current; + } + + while ((ud = get_event()) != NULL) { usbip_dbg_eh("pending event %lx\n", ud->event); /* @@ -38,79 +90,102 @@ static int event_handler(struct usbip_device *ud) */ if (ud->event & USBIP_EH_SHUTDOWN) { ud->eh_ops.shutdown(ud); - ud->event &= ~USBIP_EH_SHUTDOWN; + unset_event(ud, USBIP_EH_SHUTDOWN); } /* Reset the device. */ if (ud->event & USBIP_EH_RESET) { ud->eh_ops.reset(ud); - ud->event &= ~USBIP_EH_RESET; + unset_event(ud, USBIP_EH_RESET); } /* Mark the device as unusable. */ if (ud->event & USBIP_EH_UNUSABLE) { ud->eh_ops.unusable(ud); - ud->event &= ~USBIP_EH_UNUSABLE; + unset_event(ud, USBIP_EH_UNUSABLE); } /* Stop the error handler. */ if (ud->event & USBIP_EH_BYE) - return -1; + usbip_dbg_eh("removed %p\n", ud); + + wake_up(&ud->eh_waitq); } +} +int usbip_start_eh(struct usbip_device *ud) +{ + init_waitqueue_head(&ud->eh_waitq); + ud->event = 0; return 0; } +EXPORT_SYMBOL_GPL(usbip_start_eh); -static int event_handler_loop(void *data) +void usbip_stop_eh(struct usbip_device *ud) { - struct usbip_device *ud = data; + unsigned long pending = ud->event & ~USBIP_EH_BYE; - while (!kthread_should_stop()) { - wait_event_interruptible(ud->eh_waitq, - usbip_event_happened(ud) || - kthread_should_stop()); - usbip_dbg_eh("wakeup\n"); + if (!(ud->event & USBIP_EH_BYE)) + usbip_dbg_eh("usbip_eh stopping but not removed\n"); - if (event_handler(ud) < 0) - break; - } + if (pending) + usbip_dbg_eh("usbip_eh waiting completion %lx\n", pending); - return 0; + wait_event_interruptible(ud->eh_waitq, !(ud->event & ~USBIP_EH_BYE)); + usbip_dbg_eh("usbip_eh has stopped\n"); } +EXPORT_SYMBOL_GPL(usbip_stop_eh); -int usbip_start_eh(struct usbip_device *ud) -{ - init_waitqueue_head(&ud->eh_waitq); - ud->event = 0; +#define WORK_QUEUE_NAME "usbip_event" - ud->eh = kthread_run(event_handler_loop, ud, "usbip_eh"); - if (IS_ERR(ud->eh)) { - pr_warn("Unable to start control thread\n"); - return PTR_ERR(ud->eh); - } +static struct workqueue_struct *usbip_queue; +static DECLARE_WORK(usbip_work, event_handler); +int usbip_init_eh(void) +{ + usbip_queue = create_singlethread_workqueue(WORK_QUEUE_NAME); + if (usbip_queue == NULL) { + pr_err("failed to create usbip_event\n"); + return -ENOMEM; + } return 0; } -EXPORT_SYMBOL_GPL(usbip_start_eh); -void usbip_stop_eh(struct usbip_device *ud) +void usbip_finish_eh(void) { - if (ud->eh == current) - return; /* do not wait for myself */ - - kthread_stop(ud->eh); - usbip_dbg_eh("usbip_eh has finished\n"); + flush_workqueue(usbip_queue); + destroy_workqueue(usbip_queue); + usbip_queue = NULL; } -EXPORT_SYMBOL_GPL(usbip_stop_eh); void usbip_event_add(struct usbip_device *ud, unsigned long event) { + struct usbip_event *ue; unsigned long flags; - spin_lock_irqsave(&ud->lock, flags); - ud->event |= event; - wake_up(&ud->eh_waitq); - spin_unlock_irqrestore(&ud->lock, flags); + if (ud->event & USBIP_EH_BYE) + return; + + set_event(ud, event); + + spin_lock_irqsave(&event_lock, flags); + + list_for_each_entry_reverse(ue, &event_list, node) { + if (ue->ud == ud) + goto out; + } + + ue = kmalloc(sizeof(struct usbip_event), GFP_ATOMIC); + if (ue == NULL) + goto out; + + ue->ud = ud; + + list_add_tail(&ue->node, &event_list); + queue_work(usbip_queue, &usbip_work); + +out: + spin_unlock_irqrestore(&event_lock, flags); } EXPORT_SYMBOL_GPL(usbip_event_add); @@ -127,3 +202,12 @@ int usbip_event_happened(struct usbip_device *ud) return happened; } EXPORT_SYMBOL_GPL(usbip_event_happened); + +int usbip_in_eh(struct task_struct *task) +{ + if (task == worker_context) + return 1; + + return 0; +} +EXPORT_SYMBOL_GPL(usbip_in_eh); |