1 /*
2  * videobuf2-core.h - V4L2 driver helper framework
3  *
4  * Copyright (C) 2010 Samsung Electronics
5  *
6  * Author: Pawel Osciak <pawel@osciak.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation.
11  */
12 #ifndef _MEDIA_VIDEOBUF2_CORE_H
13 #define _MEDIA_VIDEOBUF2_CORE_H
14 
15 #include <linux/mm_types.h>
16 #include <linux/mutex.h>
17 #include <linux/poll.h>
18 #include <linux/videodev2.h>
19 #include <linux/dma-buf.h>
20 
21 struct vb2_alloc_ctx;
22 struct vb2_fileio_data;
23 
24 /**
25  * struct vb2_mem_ops - memory handling/memory allocator operations
26  * @alloc:	allocate video memory and, optionally, allocator private data,
27  *		return NULL on failure or a pointer to allocator private,
28  *		per-buffer data on success; the returned private structure
29  *		will then be passed as buf_priv argument to other ops in this
30  *		structure. Additional gfp_flags to use when allocating the
31  *		are also passed to this operation. These flags are from the
32  *		gfp_flags field of vb2_queue.
33  * @put:	inform the allocator that the buffer will no longer be used;
34  *		usually will result in the allocator freeing the buffer (if
35  *		no other users of this buffer are present); the buf_priv
36  *		argument is the allocator private per-buffer structure
37  *		previously returned from the alloc callback.
38  * @get_userptr: acquire userspace memory for a hardware operation; used for
39  *		 USERPTR memory types; vaddr is the address passed to the
40  *		 videobuf layer when queuing a video buffer of USERPTR type;
41  *		 should return an allocator private per-buffer structure
42  *		 associated with the buffer on success, NULL on failure;
43  *		 the returned private structure will then be passed as buf_priv
44  *		 argument to other ops in this structure.
45  * @put_userptr: inform the allocator that a USERPTR buffer will no longer
46  *		 be used.
47  * @attach_dmabuf: attach a shared struct dma_buf for a hardware operation;
48  *		   used for DMABUF memory types; alloc_ctx is the alloc context
49  *		   dbuf is the shared dma_buf; returns NULL on failure;
50  *		   allocator private per-buffer structure on success;
51  *		   this needs to be used for further accesses to the buffer.
52  * @detach_dmabuf: inform the exporter of the buffer that the current DMABUF
53  *		   buffer is no longer used; the buf_priv argument is the
54  *		   allocator private per-buffer structure previously returned
55  *		   from the attach_dmabuf callback.
56  * @map_dmabuf: request for access to the dmabuf from allocator; the allocator
57  *		of dmabuf is informed that this driver is going to use the
58  *		dmabuf.
59  * @unmap_dmabuf: releases access control to the dmabuf - allocator is notified
60  *		  that this driver is done using the dmabuf for now.
61  * @prepare:	called every time the buffer is passed from userspace to the
62  *		driver, useful for cache synchronisation, optional.
63  * @finish:	called every time the buffer is passed back from the driver
64  *		to the userspace, also optional.
65  * @vaddr:	return a kernel virtual address to a given memory buffer
66  *		associated with the passed private structure or NULL if no
67  *		such mapping exists.
68  * @cookie:	return allocator specific cookie for a given memory buffer
69  *		associated with the passed private structure or NULL if not
70  *		available.
71  * @num_users:	return the current number of users of a memory buffer;
72  *		return 1 if the videobuf layer (or actually the driver using
73  *		it) is the only user.
74  * @mmap:	setup a userspace mapping for a given memory buffer under
75  *		the provided virtual memory region.
76  *
77  * Required ops for USERPTR types: get_userptr, put_userptr.
78  * Required ops for MMAP types: alloc, put, num_users, mmap.
79  * Required ops for read/write access types: alloc, put, num_users, vaddr.
80  * Required ops for DMABUF types: attach_dmabuf, detach_dmabuf, map_dmabuf,
81  *				  unmap_dmabuf.
82  */
83 struct vb2_mem_ops {
84 	void		*(*alloc)(void *alloc_ctx, unsigned long size, gfp_t gfp_flags);
85 	void		(*put)(void *buf_priv);
86 	struct dma_buf *(*get_dmabuf)(void *buf_priv, unsigned long flags);
87 
88 	void		*(*get_userptr)(void *alloc_ctx, unsigned long vaddr,
89 					unsigned long size, int write);
90 	void		(*put_userptr)(void *buf_priv);
91 
92 	void		(*prepare)(void *buf_priv);
93 	void		(*finish)(void *buf_priv);
94 
95 	void		*(*attach_dmabuf)(void *alloc_ctx, struct dma_buf *dbuf,
96 				unsigned long size, int write);
97 	void		(*detach_dmabuf)(void *buf_priv);
98 	int		(*map_dmabuf)(void *buf_priv);
99 	void		(*unmap_dmabuf)(void *buf_priv);
100 
101 	void		*(*vaddr)(void *buf_priv);
102 	void		*(*cookie)(void *buf_priv);
103 
104 	unsigned int	(*num_users)(void *buf_priv);
105 
106 	int		(*mmap)(void *buf_priv, struct vm_area_struct *vma);
107 };
108 
109 struct vb2_plane {
110 	void			*mem_priv;
111 	struct dma_buf		*dbuf;
112 	unsigned int		dbuf_mapped;
113 };
114 
115 /**
116  * enum vb2_io_modes - queue access methods
117  * @VB2_MMAP:		driver supports MMAP with streaming API
118  * @VB2_USERPTR:	driver supports USERPTR with streaming API
119  * @VB2_READ:		driver supports read() style access
120  * @VB2_WRITE:		driver supports write() style access
121  * @VB2_DMABUF:		driver supports DMABUF with streaming API
122  */
123 enum vb2_io_modes {
124 	VB2_MMAP	= (1 << 0),
125 	VB2_USERPTR	= (1 << 1),
126 	VB2_READ	= (1 << 2),
127 	VB2_WRITE	= (1 << 3),
128 	VB2_DMABUF	= (1 << 4),
129 };
130 
131 /**
132  * enum vb2_fileio_flags - flags for selecting a mode of the file io emulator,
133  * by default the 'streaming' style is used by the file io emulator
134  * @VB2_FILEIO_READ_ONCE:	report EOF after reading the first buffer
135  * @VB2_FILEIO_WRITE_IMMEDIATELY:	queue buffer after each write() call
136  */
137 enum vb2_fileio_flags {
138 	VB2_FILEIO_READ_ONCE		= (1 << 0),
139 	VB2_FILEIO_WRITE_IMMEDIATELY	= (1 << 1),
140 };
141 
142 /**
143  * enum vb2_buffer_state - current video buffer state
144  * @VB2_BUF_STATE_DEQUEUED:	buffer under userspace control
145  * @VB2_BUF_STATE_PREPARING:	buffer is being prepared in videobuf
146  * @VB2_BUF_STATE_PREPARED:	buffer prepared in videobuf and by the driver
147  * @VB2_BUF_STATE_QUEUED:	buffer queued in videobuf, but not in driver
148  * @VB2_BUF_STATE_ACTIVE:	buffer queued in driver and possibly used
149  *				in a hardware operation
150  * @VB2_BUF_STATE_DONE:		buffer returned from driver to videobuf, but
151  *				not yet dequeued to userspace
152  * @VB2_BUF_STATE_ERROR:	same as above, but the operation on the buffer
153  *				has ended with an error, which will be reported
154  *				to the userspace when it is dequeued
155  */
156 enum vb2_buffer_state {
157 	VB2_BUF_STATE_DEQUEUED,
158 	VB2_BUF_STATE_PREPARING,
159 	VB2_BUF_STATE_PREPARED,
160 	VB2_BUF_STATE_QUEUED,
161 	VB2_BUF_STATE_ACTIVE,
162 	VB2_BUF_STATE_DONE,
163 	VB2_BUF_STATE_ERROR,
164 };
165 
166 struct vb2_queue;
167 
168 /**
169  * struct vb2_buffer - represents a video buffer
170  * @v4l2_buf:		struct v4l2_buffer associated with this buffer; can
171  *			be read by the driver and relevant entries can be
172  *			changed by the driver in case of CAPTURE types
173  *			(such as timestamp)
174  * @v4l2_planes:	struct v4l2_planes associated with this buffer; can
175  *			be read by the driver and relevant entries can be
176  *			changed by the driver in case of CAPTURE types
177  *			(such as bytesused); NOTE that even for single-planar
178  *			types, the v4l2_planes[0] struct should be used
179  *			instead of v4l2_buf for filling bytesused - drivers
180  *			should use the vb2_set_plane_payload() function for that
181  * @vb2_queue:		the queue to which this driver belongs
182  * @num_planes:		number of planes in the buffer
183  *			on an internal driver queue
184  * @state:		current buffer state; do not change
185  * @queued_entry:	entry on the queued buffers list, which holds all
186  *			buffers queued from userspace
187  * @done_entry:		entry on the list that stores all buffers ready to
188  *			be dequeued to userspace
189  * @planes:		private per-plane information; do not change
190  */
191 struct vb2_buffer {
192 	struct v4l2_buffer	v4l2_buf;
193 	struct v4l2_plane	v4l2_planes[VIDEO_MAX_PLANES];
194 
195 	struct vb2_queue	*vb2_queue;
196 
197 	unsigned int		num_planes;
198 
199 /* Private: internal use only */
200 	enum vb2_buffer_state	state;
201 
202 	struct list_head	queued_entry;
203 	struct list_head	done_entry;
204 
205 	struct vb2_plane	planes[VIDEO_MAX_PLANES];
206 
207 #ifdef CONFIG_VIDEO_ADV_DEBUG
208 	/*
209 	 * Counters for how often these buffer-related ops are
210 	 * called. Used to check for unbalanced ops.
211 	 */
212 	u32		cnt_mem_alloc;
213 	u32		cnt_mem_put;
214 	u32		cnt_mem_get_dmabuf;
215 	u32		cnt_mem_get_userptr;
216 	u32		cnt_mem_put_userptr;
217 	u32		cnt_mem_prepare;
218 	u32		cnt_mem_finish;
219 	u32		cnt_mem_attach_dmabuf;
220 	u32		cnt_mem_detach_dmabuf;
221 	u32		cnt_mem_map_dmabuf;
222 	u32		cnt_mem_unmap_dmabuf;
223 	u32		cnt_mem_vaddr;
224 	u32		cnt_mem_cookie;
225 	u32		cnt_mem_num_users;
226 	u32		cnt_mem_mmap;
227 
228 	u32		cnt_buf_init;
229 	u32		cnt_buf_prepare;
230 	u32		cnt_buf_finish;
231 	u32		cnt_buf_cleanup;
232 	u32		cnt_buf_queue;
233 
234 	/* This counts the number of calls to vb2_buffer_done() */
235 	u32		cnt_buf_done;
236 #endif
237 };
238 
239 /**
240  * struct vb2_ops - driver-specific callbacks
241  *
242  * @queue_setup:	called from VIDIOC_REQBUFS and VIDIOC_CREATE_BUFS
243  *			handlers before memory allocation, or, if
244  *			*num_planes != 0, after the allocation to verify a
245  *			smaller number of buffers. Driver should return
246  *			the required number of buffers in *num_buffers, the
247  *			required number of planes per buffer in *num_planes; the
248  *			size of each plane should be set in the sizes[] array
249  *			and optional per-plane allocator specific context in the
250  *			alloc_ctxs[] array. When called from VIDIOC_REQBUFS,
251  *			fmt == NULL, the driver has to use the currently
252  *			configured format and *num_buffers is the total number
253  *			of buffers, that are being allocated. When called from
254  *			VIDIOC_CREATE_BUFS, fmt != NULL and it describes the
255  *			target frame format (if the format isn't valid the
256  *			callback must return -EINVAL). In this case *num_buffers
257  *			are being allocated additionally to q->num_buffers.
258  * @wait_prepare:	release any locks taken while calling vb2 functions;
259  *			it is called before an ioctl needs to wait for a new
260  *			buffer to arrive; required to avoid a deadlock in
261  *			blocking access type.
262  * @wait_finish:	reacquire all locks released in the previous callback;
263  *			required to continue operation after sleeping while
264  *			waiting for a new buffer to arrive.
265  * @buf_init:		called once after allocating a buffer (in MMAP case)
266  *			or after acquiring a new USERPTR buffer; drivers may
267  *			perform additional buffer-related initialization;
268  *			initialization failure (return != 0) will prevent
269  *			queue setup from completing successfully; optional.
270  * @buf_prepare:	called every time the buffer is queued from userspace
271  *			and from the VIDIOC_PREPARE_BUF ioctl; drivers may
272  *			perform any initialization required before each hardware
273  *			operation in this callback; drivers that support
274  *			VIDIOC_CREATE_BUFS must also validate the buffer size;
275  *			if an error is returned, the buffer will not be queued
276  *			in driver; optional.
277  * @buf_finish:		called before every dequeue of the buffer back to
278  *			userspace; drivers may perform any operations required
279  *			before userspace accesses the buffer; optional. The
280  *			buffer state can be one of the following: DONE and
281  *			ERROR occur while streaming is in progress, and the
282  *			PREPARED state occurs when the queue has been canceled
283  *			and all pending buffers are being returned to their
284  *			default DEQUEUED state. Typically you only have to do
285  *			something if the state is VB2_BUF_STATE_DONE, since in
286  *			all other cases the buffer contents will be ignored
287  *			anyway.
288  * @buf_cleanup:	called once before the buffer is freed; drivers may
289  *			perform any additional cleanup; optional.
290  * @start_streaming:	called once to enter 'streaming' state; the driver may
291  *			receive buffers with @buf_queue callback before
292  *			@start_streaming is called; the driver gets the number
293  *			of already queued buffers in count parameter; driver
294  *			can return an error if hardware fails, in that case all
295  *			buffers that have been already given by the @buf_queue
296  *			callback are invalidated.
297  *			If there were not enough queued buffers to start
298  *			streaming, then this callback returns -ENOBUFS, and the
299  *			vb2 core will retry calling @start_streaming when a new
300  *			buffer is queued.
301  * @stop_streaming:	called when 'streaming' state must be disabled; driver
302  *			should stop any DMA transactions or wait until they
303  *			finish and give back all buffers it got from buf_queue()
304  *			callback; may use vb2_wait_for_all_buffers() function
305  * @buf_queue:		passes buffer vb to the driver; driver may start
306  *			hardware operation on this buffer; driver should give
307  *			the buffer back by calling vb2_buffer_done() function;
308  *			it is allways called after calling STREAMON ioctl;
309  *			might be called before start_streaming callback if user
310  *			pre-queued buffers before calling STREAMON.
311  */
312 struct vb2_ops {
313 	int (*queue_setup)(struct vb2_queue *q, const struct v4l2_format *fmt,
314 			   unsigned int *num_buffers, unsigned int *num_planes,
315 			   unsigned int sizes[], void *alloc_ctxs[]);
316 
317 	void (*wait_prepare)(struct vb2_queue *q);
318 	void (*wait_finish)(struct vb2_queue *q);
319 
320 	int (*buf_init)(struct vb2_buffer *vb);
321 	int (*buf_prepare)(struct vb2_buffer *vb);
322 	void (*buf_finish)(struct vb2_buffer *vb);
323 	void (*buf_cleanup)(struct vb2_buffer *vb);
324 
325 	int (*start_streaming)(struct vb2_queue *q, unsigned int count);
326 	int (*stop_streaming)(struct vb2_queue *q);
327 
328 	void (*buf_queue)(struct vb2_buffer *vb);
329 };
330 
331 struct v4l2_fh;
332 
333 /**
334  * struct vb2_queue - a videobuf queue
335  *
336  * @type:	queue type (see V4L2_BUF_TYPE_* in linux/videodev2.h
337  * @io_modes:	supported io methods (see vb2_io_modes enum)
338  * @io_flags:	additional io flags (see vb2_fileio_flags enum)
339  * @lock:	pointer to a mutex that protects the vb2_queue struct. The
340  *		driver can set this to a mutex to let the v4l2 core serialize
341  *		the queuing ioctls. If the driver wants to handle locking
342  *		itself, then this should be set to NULL. This lock is not used
343  *		by the videobuf2 core API.
344  * @owner:	The filehandle that 'owns' the buffers, i.e. the filehandle
345  *		that called reqbufs, create_buffers or started fileio.
346  *		This field is not used by the videobuf2 core API, but it allows
347  *		drivers to easily associate an owner filehandle with the queue.
348  * @ops:	driver-specific callbacks
349  * @mem_ops:	memory allocator specific callbacks
350  * @drv_priv:	driver private data
351  * @buf_struct_size: size of the driver-specific buffer structure;
352  *		"0" indicates the driver doesn't want to use a custom buffer
353  *		structure type, so sizeof(struct vb2_buffer) will is used
354  * @timestamp_flags: Timestamp flags; V4L2_BUF_FLAGS_TIMESTAMP_* and
355  *		V4L2_BUF_FLAGS_TSTAMP_SRC_*
356  * @gfp_flags:	additional gfp flags used when allocating the buffers.
357  *		Typically this is 0, but it may be e.g. GFP_DMA or __GFP_DMA32
358  *		to force the buffer allocation to a specific memory zone.
359  * @min_buffers_needed: the minimum number of buffers needed before
360  *		start_streaming() can be called. Used when a DMA engine
361  *		cannot be started unless at least this number of buffers
362  *		have been queued into the driver.
363  *
364  * @memory:	current memory type used
365  * @bufs:	videobuf buffer structures
366  * @num_buffers: number of allocated/used buffers
367  * @queued_list: list of buffers currently queued from userspace
368  * @queued_count: number of buffers queued and ready for streaming.
369  * @owned_by_drv_count: number of buffers owned by the driver
370  * @done_list:	list of buffers ready to be dequeued to userspace
371  * @done_lock:	lock to protect done_list list
372  * @done_wq:	waitqueue for processes waiting for buffers ready to be dequeued
373  * @alloc_ctx:	memory type/allocator-specific contexts for each plane
374  * @streaming:	current streaming state
375  * @start_streaming_called: start_streaming() was called successfully and we
376  *		started streaming.
377  * @fileio:	file io emulator internal data, used only if emulator is active
378  */
379 struct vb2_queue {
380 	enum v4l2_buf_type		type;
381 	unsigned int			io_modes;
382 	unsigned int			io_flags;
383 	struct mutex			*lock;
384 	struct v4l2_fh			*owner;
385 
386 	const struct vb2_ops		*ops;
387 	const struct vb2_mem_ops	*mem_ops;
388 	void				*drv_priv;
389 	unsigned int			buf_struct_size;
390 	u32				timestamp_flags;
391 	gfp_t				gfp_flags;
392 	u32				min_buffers_needed;
393 
394 /* private: internal use only */
395 	enum v4l2_memory		memory;
396 	struct vb2_buffer		*bufs[VIDEO_MAX_FRAME];
397 	unsigned int			num_buffers;
398 
399 	struct list_head		queued_list;
400 	unsigned int			queued_count;
401 
402 	atomic_t			owned_by_drv_count;
403 	struct list_head		done_list;
404 	spinlock_t			done_lock;
405 	wait_queue_head_t		done_wq;
406 
407 	void				*alloc_ctx[VIDEO_MAX_PLANES];
408 	unsigned int			plane_sizes[VIDEO_MAX_PLANES];
409 
410 	unsigned int			streaming:1;
411 	unsigned int			start_streaming_called:1;
412 
413 	struct vb2_fileio_data		*fileio;
414 
415 #ifdef CONFIG_VIDEO_ADV_DEBUG
416 	/*
417 	 * Counters for how often these queue-related ops are
418 	 * called. Used to check for unbalanced ops.
419 	 */
420 	u32				cnt_queue_setup;
421 	u32				cnt_wait_prepare;
422 	u32				cnt_wait_finish;
423 	u32				cnt_start_streaming;
424 	u32				cnt_stop_streaming;
425 #endif
426 };
427 
428 void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no);
429 void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no);
430 
431 void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state);
432 int vb2_wait_for_all_buffers(struct vb2_queue *q);
433 
434 int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b);
435 int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req);
436 
437 int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create);
438 int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b);
439 
440 int __must_check vb2_queue_init(struct vb2_queue *q);
441 
442 void vb2_queue_release(struct vb2_queue *q);
443 
444 int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b);
445 int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb);
446 int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking);
447 
448 int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type);
449 int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type);
450 
451 int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma);
452 #ifndef CONFIG_MMU
453 unsigned long vb2_get_unmapped_area(struct vb2_queue *q,
454 				    unsigned long addr,
455 				    unsigned long len,
456 				    unsigned long pgoff,
457 				    unsigned long flags);
458 #endif
459 unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait);
460 size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count,
461 		loff_t *ppos, int nonblock);
462 size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count,
463 		loff_t *ppos, int nonblock);
464 
465 /**
466  * vb2_is_streaming() - return streaming status of the queue
467  * @q:		videobuf queue
468  */
469 static inline bool vb2_is_streaming(struct vb2_queue *q)
470 {
471 	return q->streaming;
472 }
473 
474 /**
475  * vb2_is_busy() - return busy status of the queue
476  * @q:		videobuf queue
477  *
478  * This function checks if queue has any buffers allocated.
479  */
480 static inline bool vb2_is_busy(struct vb2_queue *q)
481 {
482 	return (q->num_buffers > 0);
483 }
484 
485 /**
486  * vb2_get_drv_priv() - return driver private data associated with the queue
487  * @q:		videobuf queue
488  */
489 static inline void *vb2_get_drv_priv(struct vb2_queue *q)
490 {
491 	return q->drv_priv;
492 }
493 
494 /**
495  * vb2_set_plane_payload() - set bytesused for the plane plane_no
496  * @vb:		buffer for which plane payload should be set
497  * @plane_no:	plane number for which payload should be set
498  * @size:	payload in bytes
499  */
500 static inline void vb2_set_plane_payload(struct vb2_buffer *vb,
501 				 unsigned int plane_no, unsigned long size)
502 {
503 	if (plane_no < vb->num_planes)
504 		vb->v4l2_planes[plane_no].bytesused = size;
505 }
506 
507 /**
508  * vb2_get_plane_payload() - get bytesused for the plane plane_no
509  * @vb:		buffer for which plane payload should be set
510  * @plane_no:	plane number for which payload should be set
511  * @size:	payload in bytes
512  */
513 static inline unsigned long vb2_get_plane_payload(struct vb2_buffer *vb,
514 				 unsigned int plane_no)
515 {
516 	if (plane_no < vb->num_planes)
517 		return vb->v4l2_planes[plane_no].bytesused;
518 	return 0;
519 }
520 
521 /**
522  * vb2_plane_size() - return plane size in bytes
523  * @vb:		buffer for which plane size should be returned
524  * @plane_no:	plane number for which size should be returned
525  */
526 static inline unsigned long
527 vb2_plane_size(struct vb2_buffer *vb, unsigned int plane_no)
528 {
529 	if (plane_no < vb->num_planes)
530 		return vb->v4l2_planes[plane_no].length;
531 	return 0;
532 }
533 
534 /*
535  * The following functions are not part of the vb2 core API, but are simple
536  * helper functions that you can use in your struct v4l2_file_operations,
537  * struct v4l2_ioctl_ops and struct vb2_ops. They will serialize if vb2_queue->lock
538  * or video_device->lock is set, and they will set and test vb2_queue->owner
539  * to check if the calling filehandle is permitted to do the queuing operation.
540  */
541 
542 /* struct v4l2_ioctl_ops helpers */
543 
544 int vb2_ioctl_reqbufs(struct file *file, void *priv,
545 			  struct v4l2_requestbuffers *p);
546 int vb2_ioctl_create_bufs(struct file *file, void *priv,
547 			  struct v4l2_create_buffers *p);
548 int vb2_ioctl_prepare_buf(struct file *file, void *priv,
549 			  struct v4l2_buffer *p);
550 int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p);
551 int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p);
552 int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p);
553 int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i);
554 int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i);
555 int vb2_ioctl_expbuf(struct file *file, void *priv,
556 	struct v4l2_exportbuffer *p);
557 
558 /* struct v4l2_file_operations helpers */
559 
560 int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma);
561 int vb2_fop_release(struct file *file);
562 int _vb2_fop_release(struct file *file, struct mutex *lock);
563 ssize_t vb2_fop_write(struct file *file, const char __user *buf,
564 		size_t count, loff_t *ppos);
565 ssize_t vb2_fop_read(struct file *file, char __user *buf,
566 		size_t count, loff_t *ppos);
567 unsigned int vb2_fop_poll(struct file *file, poll_table *wait);
568 #ifndef CONFIG_MMU
569 unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr,
570 		unsigned long len, unsigned long pgoff, unsigned long flags);
571 #endif
572 
573 /* struct vb2_ops helpers, only use if vq->lock is non-NULL. */
574 
575 void vb2_ops_wait_prepare(struct vb2_queue *vq);
576 void vb2_ops_wait_finish(struct vb2_queue *vq);
577 
578 #endif /* _MEDIA_VIDEOBUF2_CORE_H */
579