/* * include/linux/sync.h * * Copyright (C) 2012 Google, Inc. * * 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. * */ #ifndef _LINUX_SYNC_H#define _LINUX_SYNC_H #include <linux/types.h>#include <linux/kref.h>#include <linux/ktime.h>#include <linux/list.h>#include <linux/spinlock.h>#include <linux/wait.h>#include <linux/fence.h> #include "uapi/sync.h" struct sync_timeline;struct sync_pt;struct sync_fence; /** * struct sync_timeline_ops - sync object implementation ops * @driver_name:	name of the implementation * @dup:		duplicate a sync_pt * @has_signaled:	returns: *			  1 if pt has signaled *			  0 if pt has not signaled *			 <0 on error * @compare:		returns: *			  1 if b will signal before a *			  0 if a and b will signal at the same time *			 -1 if a will signal before b * @free_pt:		called before sync_pt is freed * @release_obj:	called before sync_timeline is freed * @fill_driver_data:	write implementation specific driver data to data. *			  should return an error if there is not enough room *			  as specified by size.  This information is returned *			  to userspace by SYNC_IOC_FENCE_INFO. * @timeline_value_str: fill str with the value of the sync_timeline's counter * @pt_value_str:	fill str with the value of the sync_pt */struct sync_timeline_ops {	const char *driver_name; 	/* required */	struct sync_pt * (*dup)(struct sync_pt *pt); 	/* required */	int (*has_signaled)(struct sync_pt *pt); 	/* required */	int (*compare)(struct sync_pt *a, struct sync_pt *b); 	/* optional */	void (*free_pt)(struct sync_pt *sync_pt); 	/* optional */	void (*release_obj)(struct sync_timeline *sync_timeline); 	/* optional */	int (*fill_driver_data)(struct sync_pt *syncpt, void *data, int size); 	/* optional */	void (*timeline_value_str)(struct sync_timeline *timeline, char *str,				   int size); 	/* optional */	void (*pt_value_str)(struct sync_pt *pt, char *str, int size);}; /** * struct sync_timeline - sync object * @kref:		reference count on fence. * @ops:		ops that define the implementation of the sync_timeline * @name:		name of the sync_timeline. Useful for debugging * @destroyed:		set when sync_timeline is destroyed * @child_list_head:	list of children sync_pts for this sync_timeline * @child_list_lock:	lock protecting @child_list_head, destroyed, and *			  sync_pt.status * @active_list_head:	list of active (unsignaled/errored) sync_pts * @sync_timeline_list:	membership in global sync_timeline_list */struct sync_timeline {	struct kref		kref;	const struct sync_timeline_ops	*ops;	char			name[32]; 	/* protected by child_list_lock */	bool			destroyed;	int			context, value; 	struct list_head	child_list_head;	spinlock_t		child_list_lock; 	struct list_head	active_list_head; #ifdef CONFIG_DEBUG_FS	struct list_head	sync_timeline_list;#endif}; /** * struct sync_pt - sync point * @fence:		base fence class * @child_list:		membership in sync_timeline.child_list_head * @active_list:	membership in sync_timeline.active_list_head * @signaled_list:	membership in temporary signaled_list on stack * @fence:		sync_fence to which the sync_pt belongs * @pt_list:		membership in sync_fence.pt_list_head * @status:		1: signaled, 0:active, <0: error * @timestamp:		time which sync_pt status transitioned from active to *			  signaled or error. */struct sync_pt {	struct fence base; 	struct list_head	child_list;	struct list_head	active_list;}; static inline struct sync_timeline *sync_pt_parent(struct sync_pt *pt){	return container_of(pt->base.lock, struct sync_timeline,			    child_list_lock);} struct sync_fence_cb {	struct fence_cb cb;	struct fence *sync_pt;	struct sync_fence *fence;}; /** * struct sync_fence - sync fence * @file:		file representing this fence * @kref:		reference count on fence. * @name:		name of sync_fence.  Useful for debugging * @pt_list_head:	list of sync_pts in the fence.  immutable once fence *			  is created * @status:		0: signaled, >0:active, <0: error * * @wq:			wait queue for fence signaling * @sync_fence_list:	membership in global fence list */struct sync_fence {	struct file		*file;	struct kref		kref;	char			name[32];#ifdef CONFIG_DEBUG_FS	struct list_head	sync_fence_list;#endif	int num_fences; 	wait_queue_head_t	wq;	atomic_t		status; 	struct sync_fence_cb	cbs[];}; struct sync_fence_waiter;typedef void (*sync_callback_t)(struct sync_fence *fence,				struct sync_fence_waiter *waiter); /** * struct sync_fence_waiter - metadata for asynchronous waiter on a fence * @waiter_list:	membership in sync_fence.waiter_list_head * @callback:		function pointer to call when fence signals * @callback_data:	pointer to pass to @callback */struct sync_fence_waiter {	wait_queue_t work;	sync_callback_t callback;}; static inline void sync_fence_waiter_init(struct sync_fence_waiter *waiter,					  sync_callback_t callback){	INIT_LIST_HEAD(&waiter->work.task_list);	waiter->callback = callback;} /* * API for sync_timeline implementers */ /** * sync_timeline_create() - creates a sync object * @ops:	specifies the implementation ops for the object * @size:	size to allocate for this obj * @name:	sync_timeline name * * Creates a new sync_timeline which will use the implementation specified by * @ops.  @size bytes will be allocated allowing for implementation specific * data to be kept after the generic sync_timeline struct. */struct sync_timeline *sync_timeline_create(const struct sync_timeline_ops *ops,					   int size, const char *name); /** * sync_timeline_destroy() - destroys a sync object * @obj:	sync_timeline to destroy * * A sync implementation should call this when the @obj is going away * (i.e. module unload.)  @obj won't actually be freed until all its children * sync_pts are freed. */void sync_timeline_destroy(struct sync_timeline *obj); /** * sync_timeline_signal() - signal a status change on a sync_timeline * @obj:	sync_timeline to signal * * A sync implementation should call this any time one of it's sync_pts * has signaled or has an error condition. */void sync_timeline_signal(struct sync_timeline *obj); /** * sync_pt_create() - creates a sync pt * @parent:	sync_pt's parent sync_timeline * @size:	size to allocate for this pt * * Creates a new sync_pt as a child of @parent.  @size bytes will be * allocated allowing for implementation specific data to be kept after * the generic sync_timeline struct. */struct sync_pt *sync_pt_create(struct sync_timeline *parent, int size); /** * sync_pt_free() - frees a sync pt * @pt:		sync_pt to free * * This should only be called on sync_pts which have been created but * not added to a fence. */void sync_pt_free(struct sync_pt *pt); /** * sync_fence_create() - creates a sync fence * @name:	name of fence to create * @pt:		sync_pt to add to the fence * * Creates a fence containg @pt.  Once this is called, the fence takes * ownership of @pt. */struct sync_fence *sync_fence_create(const char *name, struct sync_pt *pt); /* * API for sync_fence consumers */ /** * sync_fence_merge() - merge two fences * @name:	name of new fence * @a:		fence a * @b:		fence b * * Creates a new fence which contains copies of all the sync_pts in both * @a and @b.  @a and @b remain valid, independent fences. */struct sync_fence *sync_fence_merge(const char *name,				    struct sync_fence *a, struct sync_fence *b); /** * sync_fence_fdget() - get a fence from an fd * @fd:		fd referencing a fence * * Ensures @fd references a valid fence, increments the refcount of the backing * file, and returns the fence. */struct sync_fence *sync_fence_fdget(int fd); /** * sync_fence_put() - puts a reference of a sync fence * @fence:	fence to put * * Puts a reference on @fence.  If this is the last reference, the fence and * all it's sync_pts will be freed */void sync_fence_put(struct sync_fence *fence); /** * sync_fence_install() - installs a fence into a file descriptor * @fence:	fence to install * @fd:		file descriptor in which to install the fence * * Installs @fence into @fd.  @fd's should be acquired through * get_unused_fd_flags(O_CLOEXEC). */void sync_fence_install(struct sync_fence *fence, int fd); /** * sync_fence_wait_async() - registers and async wait on the fence * @fence:		fence to wait on * @waiter:		waiter callback struck * * Returns 1 if @fence has already signaled. * * Registers a callback to be called when @fence signals or has an error. * @waiter should be initialized with sync_fence_waiter_init(). */int sync_fence_wait_async(struct sync_fence *fence,			  struct sync_fence_waiter *waiter); /** * sync_fence_cancel_async() - cancels an async wait * @fence:		fence to wait on * @waiter:		waiter callback struck * * returns 0 if waiter was removed from fence's async waiter list. * returns -ENOENT if waiter was not found on fence's async waiter list. * * Cancels a previously registered async wait.  Will fail gracefully if * @waiter was never registered or if @fence has already signaled @waiter. */int sync_fence_cancel_async(struct sync_fence *fence,			    struct sync_fence_waiter *waiter); /** * sync_fence_wait() - wait on fence * @fence:	fence to wait on * @tiemout:	timeout in ms * * Wait for @fence to be signaled or have an error.  Waits indefinitely * if @timeout < 0 */int sync_fence_wait(struct sync_fence *fence, long timeout); #ifdef CONFIG_DEBUG_FS extern void sync_timeline_debug_add(struct sync_timeline *obj);extern void sync_timeline_debug_remove(struct sync_timeline *obj);extern void sync_fence_debug_add(struct sync_fence *fence);extern void sync_fence_debug_remove(struct sync_fence *fence);extern void sync_dump(void); #else# define sync_timeline_debug_add(obj)# define sync_timeline_debug_remove(obj)# define sync_fence_debug_add(fence)# define sync_fence_debug_remove(fence)# define sync_dump()#endifint sync_fence_wake_up_wq(wait_queue_t *curr, unsigned mode,				 int wake_flags, void *key); #endif /* _LINUX_SYNC_H */