/* * 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>#ifdef __KERNEL__ #include <linux/kref.h>#include <linux/ktime.h>#include <linux/list.h>#include <linux/spinlock.h>#include <linux/wait.h> struct sync_timeline;struct sync_pt;struct sync_fence; /** * struct sync_timeline_ops - sync object implementation ops * @driver_name:	name of the implentation * @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 signabl before b * @free_pt:		called before sync_pt is freed * @release_obj:	called before sync_timeline is freed * @print_obj:		deprecated * @print_pt:		deprecated * @fill_driver_data:	write implmentation 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); 	/* deprecated */	void (*print_obj)(struct seq_file *s,			  struct sync_timeline *sync_timeline); 	/* deprecated */	void (*print_pt)(struct seq_file *s, struct sync_pt *sync_pt); 	/* 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 implementaiton of the sync_timeline * @name:		name of the sync_timeline. Useful for debugging * @destoryed:		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; 	struct list_head	child_list_head;	spinlock_t		child_list_lock; 	struct list_head	active_list_head;	spinlock_t		active_list_lock; 	struct list_head	sync_timeline_list;}; /** * struct sync_pt - sync point * @parent:		sync_timeline to which this sync_pt belongs * @child_list:		membership in sync_timeline.child_list_head * @active_list:	membership in sync_timeline.active_list_head * @signaled_list:	membership in temorary 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 *			  singaled or error. */struct sync_pt {	struct sync_timeline		*parent;	struct list_head	child_list; 	struct list_head	active_list;	struct list_head	signaled_list; 	struct sync_fence	*fence;	struct list_head	pt_list; 	/* protected by parent->active_list_lock */	int			status; 	ktime_t			timestamp;}; /** * struct sync_fence - sync fence * @file:		file representing this fence * @kref:		referenace count on fence. * @name:		name of sync_fence.  Useful for debugging * @pt_list_head:	list of sync_pts in ths fence.  immutable once fence *			  is created * @waiter_list_head:	list of asynchronous waiters on this fence * @waiter_list_lock:	lock protecting @waiter_list_head and @status * @status:		1: 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]; 	/* this list is immutable once the fence is created */	struct list_head	pt_list_head; 	struct list_head	waiter_list_head;	spinlock_t		waiter_list_lock; /* also protects status */	int			status; 	wait_queue_head_t	wq; 	struct list_head	sync_fence_list;}; 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 {	struct list_head	waiter_list; 	sync_callback_t		callback;}; static inline void sync_fence_waiter_init(struct sync_fence_waiter *waiter,					  sync_callback_t callback){	waiter->callback = callback;} /* * API for sync_timeline implementers */ /** * sync_timeline_create() - creates a sync object * @ops:	specifies the implemention ops for the object * @size:	size to allocate for this obj * @name:	sync_timeline name * * Creates a new sync_timeline which will use the implemetation specified by * @ops.  @size bytes will be allocated allowing for implemntation specific * data to be kept after the generic sync_timeline stuct. */struct sync_timeline *sync_timeline_create(const struct sync_timeline_ops *ops,					   int size, const char *name); /** * sync_timeline_destory() - destorys a sync object * @obj:	sync_timeline to destroy * * A sync implemntation should call this when the @obj is going away * (i.e. module unload.)  @obj won't actually be freed until all its childern * 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 implemntation 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 chiled of @parent.  @size bytes will be * allocated allowing for implemntation 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 refernnce 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 instal * @fd:		file descriptor in which to install the fence * * Installs @fence into @fd.  @fd's should be acquired through get_unused_fd(). */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); #endif /* __KERNEL__ */ /** * struct sync_merge_data - data passed to merge ioctl * @fd2:	file descriptor of second fence * @name:	name of new fence * @fence:	returns the fd of the new fence to userspace */struct sync_merge_data {	__s32	fd2; /* fd of second fence */	char	name[32]; /* name of new fence */	__s32	fence; /* fd on newly created fence */}; /** * struct sync_pt_info - detailed sync_pt information * @len:		length of sync_pt_info including any driver_data * @obj_name:		name of parent sync_timeline * @driver_name:	name of driver implmenting the parent * @status:		status of the sync_pt 0:active 1:signaled <0:error * @timestamp_ns:	timestamp of status change in nanoseconds * @driver_data:	any driver dependant data */struct sync_pt_info {	__u32	len;	char	obj_name[32];	char	driver_name[32];	__s32	status;	__u64	timestamp_ns; 	__u8	driver_data[0];}; /** * struct sync_fence_info_data - data returned from fence info ioctl * @len:	ioctl caller writes the size of the buffer its passing in. *		ioctl returns length of sync_fence_data reutnred to userspace *		including pt_info. * @name:	name of fence * @status:	status of fence. 1: signaled 0:active <0:error * @pt_info:	a sync_pt_info struct for every sync_pt in the fence */struct sync_fence_info_data {	__u32	len;	char	name[32];	__s32	status; 	__u8	pt_info[0];}; #define SYNC_IOC_MAGIC		'>' /** * DOC: SYNC_IOC_WAIT - wait for a fence to signal * * pass timeout in milliseconds.  Waits indefinitely timeout < 0. */#define SYNC_IOC_WAIT		_IOW(SYNC_IOC_MAGIC, 0, __s32) /** * DOC: SYNC_IOC_MERGE - merge two fences * * Takes a struct sync_merge_data.  Creates a new fence containing copies of * the sync_pts in both the calling fd and sync_merge_data.fd2.  Returns the * new fence's fd in sync_merge_data.fence */#define SYNC_IOC_MERGE		_IOWR(SYNC_IOC_MAGIC, 1, struct sync_merge_data) /** * DOC: SYNC_IOC_FENCE_INFO - get detailed information on a fence * * Takes a struct sync_fence_info_data with extra space allocated for pt_info. * Caller should write the size of the buffer into len.  On return, len is * updated to reflect the total size of the sync_fence_info_data including * pt_info. * * pt_info is a buffer containing sync_pt_infos for every sync_pt in the fence. * To itterate over the sync_pt_infos, use the sync_pt_info.len field. */#define SYNC_IOC_FENCE_INFO	_IOWR(SYNC_IOC_MAGIC, 2,\	struct sync_fence_info_data) #endif /* _LINUX_SYNC_H */