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4c98248234
Fix it to not print kernel pointer address. Remove the conditional and debug message as it isn't very useful. Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
196 lines
3.9 KiB
C
196 lines
3.9 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* Copyright (C) 2003-2008 Takahiro Hirofuchi
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* Copyright (C) 2015 Nobuo Iwata
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*/
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#include <linux/kthread.h>
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#include <linux/export.h>
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#include <linux/slab.h>
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#include <linux/workqueue.h>
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#include "usbip_common.h"
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struct usbip_event {
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struct list_head node;
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struct usbip_device *ud;
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};
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static DEFINE_SPINLOCK(event_lock);
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static LIST_HEAD(event_list);
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static void set_event(struct usbip_device *ud, unsigned long event)
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{
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unsigned long flags;
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spin_lock_irqsave(&ud->lock, flags);
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ud->event |= event;
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spin_unlock_irqrestore(&ud->lock, flags);
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}
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static void unset_event(struct usbip_device *ud, unsigned long event)
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{
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unsigned long flags;
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spin_lock_irqsave(&ud->lock, flags);
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ud->event &= ~event;
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spin_unlock_irqrestore(&ud->lock, flags);
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}
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static struct usbip_device *get_event(void)
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{
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struct usbip_event *ue = NULL;
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struct usbip_device *ud = NULL;
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unsigned long flags;
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spin_lock_irqsave(&event_lock, flags);
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if (!list_empty(&event_list)) {
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ue = list_first_entry(&event_list, struct usbip_event, node);
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list_del(&ue->node);
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}
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spin_unlock_irqrestore(&event_lock, flags);
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if (ue) {
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ud = ue->ud;
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kfree(ue);
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}
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return ud;
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}
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static struct task_struct *worker_context;
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static void event_handler(struct work_struct *work)
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{
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struct usbip_device *ud;
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if (worker_context == NULL) {
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worker_context = current;
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}
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while ((ud = get_event()) != NULL) {
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usbip_dbg_eh("pending event %lx\n", ud->event);
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/*
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* NOTE: shutdown must come first.
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* Shutdown the device.
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*/
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if (ud->event & USBIP_EH_SHUTDOWN) {
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ud->eh_ops.shutdown(ud);
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unset_event(ud, USBIP_EH_SHUTDOWN);
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}
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/* Reset the device. */
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if (ud->event & USBIP_EH_RESET) {
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ud->eh_ops.reset(ud);
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unset_event(ud, USBIP_EH_RESET);
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}
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/* Mark the device as unusable. */
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if (ud->event & USBIP_EH_UNUSABLE) {
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ud->eh_ops.unusable(ud);
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unset_event(ud, USBIP_EH_UNUSABLE);
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}
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wake_up(&ud->eh_waitq);
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}
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}
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int usbip_start_eh(struct usbip_device *ud)
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{
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init_waitqueue_head(&ud->eh_waitq);
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ud->event = 0;
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return 0;
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}
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EXPORT_SYMBOL_GPL(usbip_start_eh);
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void usbip_stop_eh(struct usbip_device *ud)
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{
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unsigned long pending = ud->event & ~USBIP_EH_BYE;
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if (!(ud->event & USBIP_EH_BYE))
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usbip_dbg_eh("usbip_eh stopping but not removed\n");
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if (pending)
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usbip_dbg_eh("usbip_eh waiting completion %lx\n", pending);
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wait_event_interruptible(ud->eh_waitq, !(ud->event & ~USBIP_EH_BYE));
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usbip_dbg_eh("usbip_eh has stopped\n");
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}
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EXPORT_SYMBOL_GPL(usbip_stop_eh);
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#define WORK_QUEUE_NAME "usbip_event"
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static struct workqueue_struct *usbip_queue;
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static DECLARE_WORK(usbip_work, event_handler);
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int usbip_init_eh(void)
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{
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usbip_queue = create_singlethread_workqueue(WORK_QUEUE_NAME);
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if (usbip_queue == NULL) {
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pr_err("failed to create usbip_event\n");
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return -ENOMEM;
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}
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return 0;
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}
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void usbip_finish_eh(void)
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{
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flush_workqueue(usbip_queue);
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destroy_workqueue(usbip_queue);
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usbip_queue = NULL;
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}
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void usbip_event_add(struct usbip_device *ud, unsigned long event)
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{
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struct usbip_event *ue;
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unsigned long flags;
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if (ud->event & USBIP_EH_BYE)
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return;
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set_event(ud, event);
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spin_lock_irqsave(&event_lock, flags);
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list_for_each_entry_reverse(ue, &event_list, node) {
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if (ue->ud == ud)
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goto out;
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}
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ue = kmalloc(sizeof(struct usbip_event), GFP_ATOMIC);
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if (ue == NULL)
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goto out;
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ue->ud = ud;
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list_add_tail(&ue->node, &event_list);
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queue_work(usbip_queue, &usbip_work);
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out:
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spin_unlock_irqrestore(&event_lock, flags);
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}
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EXPORT_SYMBOL_GPL(usbip_event_add);
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int usbip_event_happened(struct usbip_device *ud)
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{
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int happened = 0;
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unsigned long flags;
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spin_lock_irqsave(&ud->lock, flags);
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if (ud->event != 0)
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happened = 1;
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spin_unlock_irqrestore(&ud->lock, flags);
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return happened;
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}
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EXPORT_SYMBOL_GPL(usbip_event_happened);
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int usbip_in_eh(struct task_struct *task)
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{
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if (task == worker_context)
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return 1;
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return 0;
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}
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EXPORT_SYMBOL_GPL(usbip_in_eh);
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