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1/*2 * Copyright (C) 2013 Red Hat3 *4 * Permission is hereby granted, free of charge, to any person obtaining a5 * copy of this software and associated documentation files (the "Software"),6 * to deal in the Software without restriction, including without limitation7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,8 * and/or sell copies of the Software, and to permit persons to whom the9 * Software is furnished to do so, subject to the following conditions:10 *11 * The above copyright notice and this permission notice (including the next12 * paragraph) shall be included in all copies or substantial portions of the13 * Software.14 *15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE21 * SOFTWARE.22 */23 24#include <linux/slab.h>25 26#include <drm/drm_flip_work.h>27#include <drm/drm_print.h>28#include <drm/drm_util.h>29 30struct drm_flip_task {31 struct list_head node;32 void *data;33};34 35static struct drm_flip_task *drm_flip_work_allocate_task(void *data, gfp_t flags)36{37 struct drm_flip_task *task;38 39 task = kzalloc(sizeof(*task), flags);40 if (task)41 task->data = data;42 43 return task;44}45 46static void drm_flip_work_queue_task(struct drm_flip_work *work, struct drm_flip_task *task)47{48 unsigned long flags;49 50 spin_lock_irqsave(&work->lock, flags);51 list_add_tail(&task->node, &work->queued);52 spin_unlock_irqrestore(&work->lock, flags);53}54 55/**56 * drm_flip_work_queue - queue work57 * @work: the flip-work58 * @val: the value to queue59 *60 * Queues work, that will later be run (passed back to drm_flip_func_t61 * func) on a work queue after drm_flip_work_commit() is called.62 */63void drm_flip_work_queue(struct drm_flip_work *work, void *val)64{65 struct drm_flip_task *task;66 67 task = drm_flip_work_allocate_task(val,68 drm_can_sleep() ? GFP_KERNEL : GFP_ATOMIC);69 if (task) {70 drm_flip_work_queue_task(work, task);71 } else {72 DRM_ERROR("%s could not allocate task!\n", work->name);73 work->func(work, val);74 }75}76EXPORT_SYMBOL(drm_flip_work_queue);77 78/**79 * drm_flip_work_commit - commit queued work80 * @work: the flip-work81 * @wq: the work-queue to run the queued work on82 *83 * Trigger work previously queued by drm_flip_work_queue() to run84 * on a workqueue. The typical usage would be to queue work (via85 * drm_flip_work_queue()) at any point (from vblank irq and/or86 * prior), and then from vblank irq commit the queued work.87 */88void drm_flip_work_commit(struct drm_flip_work *work,89 struct workqueue_struct *wq)90{91 unsigned long flags;92 93 spin_lock_irqsave(&work->lock, flags);94 list_splice_tail(&work->queued, &work->commited);95 INIT_LIST_HEAD(&work->queued);96 spin_unlock_irqrestore(&work->lock, flags);97 queue_work(wq, &work->worker);98}99EXPORT_SYMBOL(drm_flip_work_commit);100 101static void flip_worker(struct work_struct *w)102{103 struct drm_flip_work *work = container_of(w, struct drm_flip_work, worker);104 struct list_head tasks;105 unsigned long flags;106 107 while (1) {108 struct drm_flip_task *task, *tmp;109 110 INIT_LIST_HEAD(&tasks);111 spin_lock_irqsave(&work->lock, flags);112 list_splice_tail(&work->commited, &tasks);113 INIT_LIST_HEAD(&work->commited);114 spin_unlock_irqrestore(&work->lock, flags);115 116 if (list_empty(&tasks))117 break;118 119 list_for_each_entry_safe(task, tmp, &tasks, node) {120 work->func(work, task->data);121 kfree(task);122 }123 }124}125 126/**127 * drm_flip_work_init - initialize flip-work128 * @work: the flip-work to initialize129 * @name: debug name130 * @func: the callback work function131 *132 * Initializes/allocates resources for the flip-work133 */134void drm_flip_work_init(struct drm_flip_work *work,135 const char *name, drm_flip_func_t func)136{137 work->name = name;138 INIT_LIST_HEAD(&work->queued);139 INIT_LIST_HEAD(&work->commited);140 spin_lock_init(&work->lock);141 work->func = func;142 143 INIT_WORK(&work->worker, flip_worker);144}145EXPORT_SYMBOL(drm_flip_work_init);146 147/**148 * drm_flip_work_cleanup - cleans up flip-work149 * @work: the flip-work to cleanup150 *151 * Destroy resources allocated for the flip-work152 */153void drm_flip_work_cleanup(struct drm_flip_work *work)154{155 WARN_ON(!list_empty(&work->queued) || !list_empty(&work->commited));156}157EXPORT_SYMBOL(drm_flip_work_cleanup);158