/* * drivers/base/sync.c * * Copyright (C) 2012 Google, Inc. * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and * may be copied, distributed, and modified under those terms. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * */ #include <linux/debugfs.h>#include <linux/export.h>#include <linux/kernel.h>#include <linux/sched.h>#include <linux/seq_file.h>#include <linux/slab.h>#include <linux/uaccess.h>#include <linux/anon_inodes.h> #include "sync.h" #define CREATE_TRACE_POINTS#include "trace/sync.h" static const struct fence_ops android_fence_ops; struct sync_timeline *sync_timeline_create(const struct sync_timeline_ops *ops,					   int size, const char *name){	struct sync_timeline *obj; 	if (size < sizeof(struct sync_timeline))		return NULL; 	obj = kzalloc(size, GFP_KERNEL);	if (!obj)		return NULL; 	kref_init(&obj->kref);	obj->ops = ops;	obj->context = fence_context_alloc(1);	strlcpy(obj->name, name, sizeof(obj->name)); 	INIT_LIST_HEAD(&obj->child_list_head);	INIT_LIST_HEAD(&obj->active_list_head);	spin_lock_init(&obj->child_list_lock); 	sync_timeline_debug_add(obj); 	return obj;}EXPORT_SYMBOL(sync_timeline_create); static void sync_timeline_free(struct kref *kref){	struct sync_timeline *obj =		container_of(kref, struct sync_timeline, kref); 	sync_timeline_debug_remove(obj); 	kfree(obj);} static void sync_timeline_get(struct sync_timeline *obj){	kref_get(&obj->kref);} static void sync_timeline_put(struct sync_timeline *obj){	kref_put(&obj->kref, sync_timeline_free);} void sync_timeline_destroy(struct sync_timeline *obj){	obj->destroyed = true;	/*	 * Ensure timeline is marked as destroyed before	 * changing timeline's fences status.	 */	smp_wmb(); 	sync_timeline_put(obj);}EXPORT_SYMBOL(sync_timeline_destroy); void sync_timeline_signal(struct sync_timeline *obj){	unsigned long flags;	struct fence *fence, *next; 	trace_sync_timeline(obj); 	spin_lock_irqsave(&obj->child_list_lock, flags); 	list_for_each_entry_safe(fence, next, &obj->active_list_head,				 active_list) {		if (fence_is_signaled_locked(fence))			list_del_init(&fence->active_list);	} 	spin_unlock_irqrestore(&obj->child_list_lock, flags);}EXPORT_SYMBOL(sync_timeline_signal); struct fence *sync_pt_create(struct sync_timeline *obj, int size){	unsigned long flags;	struct fence *fence; 	if (size < sizeof(*fence))		return NULL; 	fence = kzalloc(size, GFP_KERNEL);	if (!fence)		return NULL; 	spin_lock_irqsave(&obj->child_list_lock, flags);	sync_timeline_get(obj);	fence_init(fence, &android_fence_ops, &obj->child_list_lock,		   obj->context, ++obj->value);	list_add_tail(&fence->child_list, &obj->child_list_head);	INIT_LIST_HEAD(&fence->active_list);	spin_unlock_irqrestore(&obj->child_list_lock, flags);	return fence;}EXPORT_SYMBOL(sync_pt_create); static const char *android_fence_get_driver_name(struct fence *fence){	struct sync_timeline *parent = fence_parent(fence); 	return parent->ops->driver_name;} static const char *android_fence_get_timeline_name(struct fence *fence){	struct sync_timeline *parent = fence_parent(fence); 	return parent->name;} static void android_fence_release(struct fence *fence){	struct sync_timeline *parent = fence_parent(fence);	unsigned long flags; 	spin_lock_irqsave(fence->lock, flags);	list_del(&fence->child_list);	if (WARN_ON_ONCE(!list_empty(&fence->active_list)))		list_del(&fence->active_list);	spin_unlock_irqrestore(fence->lock, flags); 	sync_timeline_put(parent);	fence_free(fence);} static bool android_fence_signaled(struct fence *fence){	struct sync_timeline *parent = fence_parent(fence);	int ret; 	ret = parent->ops->has_signaled(fence);	if (ret < 0)		fence->status = ret;	return ret;} static bool android_fence_enable_signaling(struct fence *fence){	struct sync_timeline *parent = fence_parent(fence); 	if (android_fence_signaled(fence))		return false; 	list_add_tail(&fence->active_list, &parent->active_list_head);	return true;} static void android_fence_value_str(struct fence *fence,				    char *str, int size){	struct sync_timeline *parent = fence_parent(fence); 	if (!parent->ops->fence_value_str) {		if (size)			*str = 0;		return;	}	parent->ops->fence_value_str(fence, str, size);} static void android_fence_timeline_value_str(struct fence *fence,					     char *str, int size){	struct sync_timeline *parent = fence_parent(fence); 	if (!parent->ops->timeline_value_str) {		if (size)			*str = 0;		return;	}	parent->ops->timeline_value_str(parent, str, size);} static const struct fence_ops android_fence_ops = {	.get_driver_name = android_fence_get_driver_name,	.get_timeline_name = android_fence_get_timeline_name,	.enable_signaling = android_fence_enable_signaling,	.signaled = android_fence_signaled,	.wait = fence_default_wait,	.release = android_fence_release,	.fence_value_str = android_fence_value_str,	.timeline_value_str = android_fence_timeline_value_str,};