/* * 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/fence.h> #include "uapi/sync.h" struct sync_timeline;struct sync_file; /** * struct sync_timeline_ops - sync object implementation ops * @driver_name:	name of the implementation * @has_signaled:	returns: *			  1 if pt has signaled *			  0 if pt has not signaled *			 <0 on error * @timeline_value_str: fill str with the value of the sync_timeline's counter * @fence_value_str:	fill str with the value of the fence */struct sync_timeline_ops {	const char *driver_name; 	/* required */	int (*has_signaled)(struct fence *fence); 	/* optional */	void (*timeline_value_str)(struct sync_timeline *timeline, char *str,				   int size); 	/* optional */	void (*fence_value_str)(struct fence *fence, 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 *			fence.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}; static inline struct sync_timeline *fence_parent(struct fence *fence){	return container_of(fence->lock, struct sync_timeline,			    child_list_lock);} struct sync_file_cb {	struct fence_cb cb;	struct fence *fence;	struct sync_file *sync_file;}; /** * struct sync_file - sync file to export to the userspace * @file:		file representing this fence * @kref:		reference count on fence. * @name:		name of sync_file.  Useful for debugging * @sync_file_list:	membership in global file list * @num_fences		number of sync_pts in the fence * @wq:			wait queue for fence signaling * @status:		0: signaled, >0:active, <0: error * @cbs:		sync_pts callback information */struct sync_file {	struct file		*file;	struct kref		kref;	char			name[32];#ifdef CONFIG_DEBUG_FS	struct list_head	sync_file_list;#endif	int num_fences; 	wait_queue_head_t	wq;	atomic_t		status; 	struct sync_file_cb	cbs[];}; /* * 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. Returns the * sync_timeline object or NULL in case of error. */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 * fences 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 fences * has signaled or has an error condition. */void sync_timeline_signal(struct sync_timeline *obj); /** * sync_pt_create() - creates a sync pt * @parent:	fence's parent sync_timeline * @size:	size to allocate for this pt * * Creates a new fence as a child of @parent.  @size bytes will be * allocated allowing for implementation specific data to be kept after * the generic sync_timeline struct. Returns the fence object or * NULL in case of error. */struct fence *sync_pt_create(struct sync_timeline *parent, int size); /** * sync_fence_create() - creates a sync fence * @name:	name of fence to create * @fence:	fence to add to the sync_fence * * Creates a sync_file containg @fence. Once this is called, the sync_file * takes ownership of @fence. */struct sync_file *sync_file_create(const char *name, struct fence *fence); /* * API for sync_file consumers */ /** * sync_file_merge() - merge two sync_files * @name:	name of new fence * @a:		sync_file a * @b:		sync_file b * * Creates a new sync_file which contains copies of all the fences in both * @a and @b.  @a and @b remain valid, independent sync_file. Returns the * new merged sync_file or NULL in case of error. */struct sync_file *sync_file_merge(const char *name,				    struct sync_file *a, struct sync_file *b); /** * sync_file_fdget() - get a sync_file from an fd * @fd:		fd referencing a fence * * Ensures @fd references a valid sync_file, increments the refcount of the * backing file. Returns the sync_file or NULL in case of error. */struct sync_file *sync_file_fdget(int fd); /** * sync_file_put() - puts a reference of a sync_file * @sync_file:	sync_file to put * * Puts a reference on @sync_fence.  If this is the last reference, the * sync_fil and all it's sync_pts will be freed */void sync_file_put(struct sync_file *sync_file); /** * sync_file_install() - installs a sync_file into a file descriptor * @sync_file:	sync_file to install * @fd:		file descriptor in which to install the fence * * Installs @sync_file into @fd.  @fd's should be acquired through * get_unused_fd_flags(O_CLOEXEC). */void sync_file_install(struct sync_file *sync_file, int fd); #ifdef CONFIG_DEBUG_FS void sync_timeline_debug_add(struct sync_timeline *obj);void sync_timeline_debug_remove(struct sync_timeline *obj);void sync_file_debug_add(struct sync_file *fence);void sync_file_debug_remove(struct sync_file *fence);void sync_dump(void); #else# define sync_timeline_debug_add(obj)# define sync_timeline_debug_remove(obj)# define sync_file_debug_add(fence)# define sync_file_debug_remove(fence)# define sync_dump()#endif #endif /* _LINUX_SYNC_H */