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e23ccc0a PO |
1 | /* |
2 | * videobuf2-core.c - V4L2 driver helper framework | |
3 | * | |
4 | * Copyright (C) 2010 Samsung Electronics | |
5 | * | |
95072084 | 6 | * Author: Pawel Osciak <pawel@osciak.com> |
e23ccc0a PO |
7 | * Marek Szyprowski <m.szyprowski@samsung.com> |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License as published by | |
11 | * the Free Software Foundation. | |
12 | */ | |
13 | ||
14 | #include <linux/err.h> | |
15 | #include <linux/kernel.h> | |
16 | #include <linux/module.h> | |
17 | #include <linux/mm.h> | |
18 | #include <linux/poll.h> | |
19 | #include <linux/slab.h> | |
20 | #include <linux/sched.h> | |
21 | ||
22 | #include <media/videobuf2-core.h> | |
23 | ||
24 | static int debug; | |
25 | module_param(debug, int, 0644); | |
26 | ||
27 | #define dprintk(level, fmt, arg...) \ | |
28 | do { \ | |
29 | if (debug >= level) \ | |
30 | printk(KERN_DEBUG "vb2: " fmt, ## arg); \ | |
31 | } while (0) | |
32 | ||
33 | #define call_memop(q, plane, op, args...) \ | |
34 | (((q)->mem_ops->op) ? \ | |
35 | ((q)->mem_ops->op(args)) : 0) | |
36 | ||
37 | #define call_qop(q, op, args...) \ | |
38 | (((q)->ops->op) ? ((q)->ops->op(args)) : 0) | |
39 | ||
ea42c8ec MS |
40 | #define V4L2_BUFFER_STATE_FLAGS (V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_QUEUED | \ |
41 | V4L2_BUF_FLAG_DONE | V4L2_BUF_FLAG_ERROR) | |
42 | ||
e23ccc0a PO |
43 | /** |
44 | * __vb2_buf_mem_alloc() - allocate video memory for the given buffer | |
45 | */ | |
46 | static int __vb2_buf_mem_alloc(struct vb2_buffer *vb, | |
47 | unsigned long *plane_sizes) | |
48 | { | |
49 | struct vb2_queue *q = vb->vb2_queue; | |
50 | void *mem_priv; | |
51 | int plane; | |
52 | ||
53 | /* Allocate memory for all planes in this buffer */ | |
54 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
55 | mem_priv = call_memop(q, plane, alloc, q->alloc_ctx[plane], | |
56 | plane_sizes[plane]); | |
62a79436 | 57 | if (IS_ERR_OR_NULL(mem_priv)) |
e23ccc0a PO |
58 | goto free; |
59 | ||
60 | /* Associate allocator private data with this plane */ | |
61 | vb->planes[plane].mem_priv = mem_priv; | |
62 | vb->v4l2_planes[plane].length = plane_sizes[plane]; | |
63 | } | |
64 | ||
65 | return 0; | |
66 | free: | |
67 | /* Free already allocated memory if one of the allocations failed */ | |
68 | for (; plane > 0; --plane) | |
69 | call_memop(q, plane, put, vb->planes[plane - 1].mem_priv); | |
70 | ||
71 | return -ENOMEM; | |
72 | } | |
73 | ||
74 | /** | |
75 | * __vb2_buf_mem_free() - free memory of the given buffer | |
76 | */ | |
77 | static void __vb2_buf_mem_free(struct vb2_buffer *vb) | |
78 | { | |
79 | struct vb2_queue *q = vb->vb2_queue; | |
80 | unsigned int plane; | |
81 | ||
82 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
83 | call_memop(q, plane, put, vb->planes[plane].mem_priv); | |
84 | vb->planes[plane].mem_priv = NULL; | |
85 | dprintk(3, "Freed plane %d of buffer %d\n", | |
86 | plane, vb->v4l2_buf.index); | |
87 | } | |
88 | } | |
89 | ||
90 | /** | |
91 | * __vb2_buf_userptr_put() - release userspace memory associated with | |
92 | * a USERPTR buffer | |
93 | */ | |
94 | static void __vb2_buf_userptr_put(struct vb2_buffer *vb) | |
95 | { | |
96 | struct vb2_queue *q = vb->vb2_queue; | |
97 | unsigned int plane; | |
98 | ||
99 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
100 | void *mem_priv = vb->planes[plane].mem_priv; | |
101 | ||
102 | if (mem_priv) { | |
103 | call_memop(q, plane, put_userptr, mem_priv); | |
104 | vb->planes[plane].mem_priv = NULL; | |
105 | } | |
106 | } | |
107 | } | |
108 | ||
109 | /** | |
110 | * __setup_offsets() - setup unique offsets ("cookies") for every plane in | |
111 | * every buffer on the queue | |
112 | */ | |
113 | static void __setup_offsets(struct vb2_queue *q) | |
114 | { | |
115 | unsigned int buffer, plane; | |
116 | struct vb2_buffer *vb; | |
117 | unsigned long off = 0; | |
118 | ||
119 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
120 | vb = q->bufs[buffer]; | |
121 | if (!vb) | |
122 | continue; | |
123 | ||
124 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
125 | vb->v4l2_planes[plane].m.mem_offset = off; | |
126 | ||
127 | dprintk(3, "Buffer %d, plane %d offset 0x%08lx\n", | |
128 | buffer, plane, off); | |
129 | ||
130 | off += vb->v4l2_planes[plane].length; | |
131 | off = PAGE_ALIGN(off); | |
132 | } | |
133 | } | |
134 | } | |
135 | ||
136 | /** | |
137 | * __vb2_queue_alloc() - allocate videobuf buffer structures and (for MMAP type) | |
138 | * video buffer memory for all buffers/planes on the queue and initializes the | |
139 | * queue | |
140 | * | |
141 | * Returns the number of buffers successfully allocated. | |
142 | */ | |
143 | static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory, | |
144 | unsigned int num_buffers, unsigned int num_planes, | |
145 | unsigned long plane_sizes[]) | |
146 | { | |
147 | unsigned int buffer; | |
148 | struct vb2_buffer *vb; | |
149 | int ret; | |
150 | ||
151 | for (buffer = 0; buffer < num_buffers; ++buffer) { | |
152 | /* Allocate videobuf buffer structures */ | |
153 | vb = kzalloc(q->buf_struct_size, GFP_KERNEL); | |
154 | if (!vb) { | |
155 | dprintk(1, "Memory alloc for buffer struct failed\n"); | |
156 | break; | |
157 | } | |
158 | ||
159 | /* Length stores number of planes for multiplanar buffers */ | |
160 | if (V4L2_TYPE_IS_MULTIPLANAR(q->type)) | |
161 | vb->v4l2_buf.length = num_planes; | |
162 | ||
163 | vb->state = VB2_BUF_STATE_DEQUEUED; | |
164 | vb->vb2_queue = q; | |
165 | vb->num_planes = num_planes; | |
166 | vb->v4l2_buf.index = buffer; | |
167 | vb->v4l2_buf.type = q->type; | |
168 | vb->v4l2_buf.memory = memory; | |
169 | ||
170 | /* Allocate video buffer memory for the MMAP type */ | |
171 | if (memory == V4L2_MEMORY_MMAP) { | |
172 | ret = __vb2_buf_mem_alloc(vb, plane_sizes); | |
173 | if (ret) { | |
174 | dprintk(1, "Failed allocating memory for " | |
175 | "buffer %d\n", buffer); | |
176 | kfree(vb); | |
177 | break; | |
178 | } | |
179 | /* | |
180 | * Call the driver-provided buffer initialization | |
181 | * callback, if given. An error in initialization | |
182 | * results in queue setup failure. | |
183 | */ | |
184 | ret = call_qop(q, buf_init, vb); | |
185 | if (ret) { | |
186 | dprintk(1, "Buffer %d %p initialization" | |
187 | " failed\n", buffer, vb); | |
188 | __vb2_buf_mem_free(vb); | |
189 | kfree(vb); | |
190 | break; | |
191 | } | |
192 | } | |
193 | ||
194 | q->bufs[buffer] = vb; | |
195 | } | |
196 | ||
197 | q->num_buffers = buffer; | |
198 | ||
199 | __setup_offsets(q); | |
200 | ||
201 | dprintk(1, "Allocated %d buffers, %d plane(s) each\n", | |
202 | q->num_buffers, num_planes); | |
203 | ||
204 | return buffer; | |
205 | } | |
206 | ||
207 | /** | |
208 | * __vb2_free_mem() - release all video buffer memory for a given queue | |
209 | */ | |
210 | static void __vb2_free_mem(struct vb2_queue *q) | |
211 | { | |
212 | unsigned int buffer; | |
213 | struct vb2_buffer *vb; | |
214 | ||
215 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
216 | vb = q->bufs[buffer]; | |
217 | if (!vb) | |
218 | continue; | |
219 | ||
220 | /* Free MMAP buffers or release USERPTR buffers */ | |
221 | if (q->memory == V4L2_MEMORY_MMAP) | |
222 | __vb2_buf_mem_free(vb); | |
223 | else | |
224 | __vb2_buf_userptr_put(vb); | |
225 | } | |
226 | } | |
227 | ||
228 | /** | |
229 | * __vb2_queue_free() - free the queue - video memory and related information | |
230 | * and return the queue to an uninitialized state. Might be called even if the | |
231 | * queue has already been freed. | |
232 | */ | |
72f1fc33 | 233 | static void __vb2_queue_free(struct vb2_queue *q) |
e23ccc0a PO |
234 | { |
235 | unsigned int buffer; | |
236 | ||
237 | /* Call driver-provided cleanup function for each buffer, if provided */ | |
238 | if (q->ops->buf_cleanup) { | |
239 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
240 | if (NULL == q->bufs[buffer]) | |
241 | continue; | |
242 | q->ops->buf_cleanup(q->bufs[buffer]); | |
243 | } | |
244 | } | |
245 | ||
246 | /* Release video buffer memory */ | |
247 | __vb2_free_mem(q); | |
248 | ||
249 | /* Free videobuf buffers */ | |
250 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
251 | kfree(q->bufs[buffer]); | |
252 | q->bufs[buffer] = NULL; | |
253 | } | |
254 | ||
255 | q->num_buffers = 0; | |
256 | q->memory = 0; | |
e23ccc0a PO |
257 | } |
258 | ||
259 | /** | |
260 | * __verify_planes_array() - verify that the planes array passed in struct | |
261 | * v4l2_buffer from userspace can be safely used | |
262 | */ | |
263 | static int __verify_planes_array(struct vb2_buffer *vb, struct v4l2_buffer *b) | |
264 | { | |
265 | /* Is memory for copying plane information present? */ | |
266 | if (NULL == b->m.planes) { | |
267 | dprintk(1, "Multi-planar buffer passed but " | |
268 | "planes array not provided\n"); | |
269 | return -EINVAL; | |
270 | } | |
271 | ||
272 | if (b->length < vb->num_planes || b->length > VIDEO_MAX_PLANES) { | |
273 | dprintk(1, "Incorrect planes array length, " | |
274 | "expected %d, got %d\n", vb->num_planes, b->length); | |
275 | return -EINVAL; | |
276 | } | |
277 | ||
278 | return 0; | |
279 | } | |
280 | ||
281 | /** | |
282 | * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be | |
283 | * returned to userspace | |
284 | */ | |
285 | static int __fill_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b) | |
286 | { | |
287 | struct vb2_queue *q = vb->vb2_queue; | |
288 | int ret = 0; | |
289 | ||
ea42c8ec | 290 | /* Copy back data such as timestamp, flags, input, etc. */ |
e23ccc0a PO |
291 | memcpy(b, &vb->v4l2_buf, offsetof(struct v4l2_buffer, m)); |
292 | b->input = vb->v4l2_buf.input; | |
293 | b->reserved = vb->v4l2_buf.reserved; | |
294 | ||
295 | if (V4L2_TYPE_IS_MULTIPLANAR(q->type)) { | |
296 | ret = __verify_planes_array(vb, b); | |
297 | if (ret) | |
298 | return ret; | |
299 | ||
300 | /* | |
301 | * Fill in plane-related data if userspace provided an array | |
302 | * for it. The memory and size is verified above. | |
303 | */ | |
304 | memcpy(b->m.planes, vb->v4l2_planes, | |
305 | b->length * sizeof(struct v4l2_plane)); | |
306 | } else { | |
307 | /* | |
308 | * We use length and offset in v4l2_planes array even for | |
309 | * single-planar buffers, but userspace does not. | |
310 | */ | |
311 | b->length = vb->v4l2_planes[0].length; | |
312 | b->bytesused = vb->v4l2_planes[0].bytesused; | |
313 | if (q->memory == V4L2_MEMORY_MMAP) | |
314 | b->m.offset = vb->v4l2_planes[0].m.mem_offset; | |
315 | else if (q->memory == V4L2_MEMORY_USERPTR) | |
316 | b->m.userptr = vb->v4l2_planes[0].m.userptr; | |
317 | } | |
318 | ||
ea42c8ec MS |
319 | /* |
320 | * Clear any buffer state related flags. | |
321 | */ | |
322 | b->flags &= ~V4L2_BUFFER_STATE_FLAGS; | |
e23ccc0a PO |
323 | |
324 | switch (vb->state) { | |
325 | case VB2_BUF_STATE_QUEUED: | |
326 | case VB2_BUF_STATE_ACTIVE: | |
327 | b->flags |= V4L2_BUF_FLAG_QUEUED; | |
328 | break; | |
329 | case VB2_BUF_STATE_ERROR: | |
330 | b->flags |= V4L2_BUF_FLAG_ERROR; | |
331 | /* fall through */ | |
332 | case VB2_BUF_STATE_DONE: | |
333 | b->flags |= V4L2_BUF_FLAG_DONE; | |
334 | break; | |
335 | case VB2_BUF_STATE_DEQUEUED: | |
336 | /* nothing */ | |
337 | break; | |
338 | } | |
339 | ||
340 | if (vb->num_planes_mapped == vb->num_planes) | |
341 | b->flags |= V4L2_BUF_FLAG_MAPPED; | |
342 | ||
343 | return ret; | |
344 | } | |
345 | ||
346 | /** | |
347 | * vb2_querybuf() - query video buffer information | |
348 | * @q: videobuf queue | |
349 | * @b: buffer struct passed from userspace to vidioc_querybuf handler | |
350 | * in driver | |
351 | * | |
352 | * Should be called from vidioc_querybuf ioctl handler in driver. | |
353 | * This function will verify the passed v4l2_buffer structure and fill the | |
354 | * relevant information for the userspace. | |
355 | * | |
356 | * The return values from this function are intended to be directly returned | |
357 | * from vidioc_querybuf handler in driver. | |
358 | */ | |
359 | int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b) | |
360 | { | |
361 | struct vb2_buffer *vb; | |
362 | ||
363 | if (b->type != q->type) { | |
364 | dprintk(1, "querybuf: wrong buffer type\n"); | |
365 | return -EINVAL; | |
366 | } | |
367 | ||
368 | if (b->index >= q->num_buffers) { | |
369 | dprintk(1, "querybuf: buffer index out of range\n"); | |
370 | return -EINVAL; | |
371 | } | |
372 | vb = q->bufs[b->index]; | |
373 | ||
374 | return __fill_v4l2_buffer(vb, b); | |
375 | } | |
376 | EXPORT_SYMBOL(vb2_querybuf); | |
377 | ||
378 | /** | |
379 | * __verify_userptr_ops() - verify that all memory operations required for | |
380 | * USERPTR queue type have been provided | |
381 | */ | |
382 | static int __verify_userptr_ops(struct vb2_queue *q) | |
383 | { | |
384 | if (!(q->io_modes & VB2_USERPTR) || !q->mem_ops->get_userptr || | |
385 | !q->mem_ops->put_userptr) | |
386 | return -EINVAL; | |
387 | ||
388 | return 0; | |
389 | } | |
390 | ||
391 | /** | |
392 | * __verify_mmap_ops() - verify that all memory operations required for | |
393 | * MMAP queue type have been provided | |
394 | */ | |
395 | static int __verify_mmap_ops(struct vb2_queue *q) | |
396 | { | |
397 | if (!(q->io_modes & VB2_MMAP) || !q->mem_ops->alloc || | |
398 | !q->mem_ops->put || !q->mem_ops->mmap) | |
399 | return -EINVAL; | |
400 | ||
401 | return 0; | |
402 | } | |
403 | ||
404 | /** | |
405 | * __buffers_in_use() - return true if any buffers on the queue are in use and | |
406 | * the queue cannot be freed (by the means of REQBUFS(0)) call | |
407 | */ | |
408 | static bool __buffers_in_use(struct vb2_queue *q) | |
409 | { | |
410 | unsigned int buffer, plane; | |
411 | struct vb2_buffer *vb; | |
412 | ||
413 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
414 | vb = q->bufs[buffer]; | |
415 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
416 | /* | |
417 | * If num_users() has not been provided, call_memop | |
418 | * will return 0, apparently nobody cares about this | |
419 | * case anyway. If num_users() returns more than 1, | |
420 | * we are not the only user of the plane's memory. | |
421 | */ | |
422 | if (call_memop(q, plane, num_users, | |
423 | vb->planes[plane].mem_priv) > 1) | |
424 | return true; | |
425 | } | |
426 | } | |
427 | ||
428 | return false; | |
429 | } | |
430 | ||
431 | /** | |
432 | * vb2_reqbufs() - Initiate streaming | |
433 | * @q: videobuf2 queue | |
434 | * @req: struct passed from userspace to vidioc_reqbufs handler in driver | |
435 | * | |
436 | * Should be called from vidioc_reqbufs ioctl handler of a driver. | |
437 | * This function: | |
438 | * 1) verifies streaming parameters passed from the userspace, | |
439 | * 2) sets up the queue, | |
440 | * 3) negotiates number of buffers and planes per buffer with the driver | |
441 | * to be used during streaming, | |
442 | * 4) allocates internal buffer structures (struct vb2_buffer), according to | |
443 | * the agreed parameters, | |
444 | * 5) for MMAP memory type, allocates actual video memory, using the | |
445 | * memory handling/allocation routines provided during queue initialization | |
446 | * | |
447 | * If req->count is 0, all the memory will be freed instead. | |
448 | * If the queue has been allocated previously (by a previous vb2_reqbufs) call | |
449 | * and the queue is not busy, memory will be reallocated. | |
450 | * | |
451 | * The return values from this function are intended to be directly returned | |
452 | * from vidioc_reqbufs handler in driver. | |
453 | */ | |
454 | int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) | |
455 | { | |
456 | unsigned int num_buffers, num_planes; | |
457 | unsigned long plane_sizes[VIDEO_MAX_PLANES]; | |
458 | int ret = 0; | |
459 | ||
b25748fe MS |
460 | if (q->fileio) { |
461 | dprintk(1, "reqbufs: file io in progress\n"); | |
462 | return -EBUSY; | |
463 | } | |
464 | ||
e23ccc0a PO |
465 | if (req->memory != V4L2_MEMORY_MMAP |
466 | && req->memory != V4L2_MEMORY_USERPTR) { | |
467 | dprintk(1, "reqbufs: unsupported memory type\n"); | |
468 | return -EINVAL; | |
469 | } | |
470 | ||
471 | if (req->type != q->type) { | |
472 | dprintk(1, "reqbufs: requested type is incorrect\n"); | |
473 | return -EINVAL; | |
474 | } | |
475 | ||
476 | if (q->streaming) { | |
477 | dprintk(1, "reqbufs: streaming active\n"); | |
478 | return -EBUSY; | |
479 | } | |
480 | ||
481 | /* | |
482 | * Make sure all the required memory ops for given memory type | |
483 | * are available. | |
484 | */ | |
485 | if (req->memory == V4L2_MEMORY_MMAP && __verify_mmap_ops(q)) { | |
486 | dprintk(1, "reqbufs: MMAP for current setup unsupported\n"); | |
487 | return -EINVAL; | |
488 | } | |
489 | ||
490 | if (req->memory == V4L2_MEMORY_USERPTR && __verify_userptr_ops(q)) { | |
491 | dprintk(1, "reqbufs: USERPTR for current setup unsupported\n"); | |
492 | return -EINVAL; | |
493 | } | |
494 | ||
29e3fbd8 | 495 | if (req->count == 0 || q->num_buffers != 0 || q->memory != req->memory) { |
e23ccc0a PO |
496 | /* |
497 | * We already have buffers allocated, so first check if they | |
498 | * are not in use and can be freed. | |
499 | */ | |
500 | if (q->memory == V4L2_MEMORY_MMAP && __buffers_in_use(q)) { | |
501 | dprintk(1, "reqbufs: memory in use, cannot free\n"); | |
502 | return -EBUSY; | |
503 | } | |
504 | ||
72f1fc33 | 505 | __vb2_queue_free(q); |
29e3fbd8 MS |
506 | |
507 | /* | |
508 | * In case of REQBUFS(0) return immediately without calling | |
509 | * driver's queue_setup() callback and allocating resources. | |
510 | */ | |
511 | if (req->count == 0) | |
512 | return 0; | |
e23ccc0a PO |
513 | } |
514 | ||
515 | /* | |
516 | * Make sure the requested values and current defaults are sane. | |
517 | */ | |
518 | num_buffers = min_t(unsigned int, req->count, VIDEO_MAX_FRAME); | |
519 | memset(plane_sizes, 0, sizeof(plane_sizes)); | |
520 | memset(q->alloc_ctx, 0, sizeof(q->alloc_ctx)); | |
13b14095 | 521 | q->memory = req->memory; |
e23ccc0a PO |
522 | |
523 | /* | |
524 | * Ask the driver how many buffers and planes per buffer it requires. | |
525 | * Driver also sets the size and allocator context for each plane. | |
526 | */ | |
527 | ret = call_qop(q, queue_setup, q, &num_buffers, &num_planes, | |
528 | plane_sizes, q->alloc_ctx); | |
529 | if (ret) | |
530 | return ret; | |
531 | ||
532 | /* Finally, allocate buffers and video memory */ | |
533 | ret = __vb2_queue_alloc(q, req->memory, num_buffers, num_planes, | |
534 | plane_sizes); | |
66072d4f MS |
535 | if (ret == 0) { |
536 | dprintk(1, "Memory allocation failed\n"); | |
537 | return -ENOMEM; | |
e23ccc0a PO |
538 | } |
539 | ||
540 | /* | |
541 | * Check if driver can handle the allocated number of buffers. | |
542 | */ | |
543 | if (ret < num_buffers) { | |
544 | unsigned int orig_num_buffers; | |
545 | ||
546 | orig_num_buffers = num_buffers = ret; | |
547 | ret = call_qop(q, queue_setup, q, &num_buffers, &num_planes, | |
548 | plane_sizes, q->alloc_ctx); | |
549 | if (ret) | |
550 | goto free_mem; | |
551 | ||
552 | if (orig_num_buffers < num_buffers) { | |
553 | ret = -ENOMEM; | |
554 | goto free_mem; | |
555 | } | |
556 | ||
557 | /* | |
558 | * Ok, driver accepted smaller number of buffers. | |
559 | */ | |
560 | ret = num_buffers; | |
561 | } | |
562 | ||
e23ccc0a PO |
563 | /* |
564 | * Return the number of successfully allocated buffers | |
565 | * to the userspace. | |
566 | */ | |
567 | req->count = ret; | |
568 | ||
569 | return 0; | |
570 | ||
571 | free_mem: | |
572 | __vb2_queue_free(q); | |
573 | return ret; | |
574 | } | |
575 | EXPORT_SYMBOL_GPL(vb2_reqbufs); | |
576 | ||
577 | /** | |
578 | * vb2_plane_vaddr() - Return a kernel virtual address of a given plane | |
579 | * @vb: vb2_buffer to which the plane in question belongs to | |
580 | * @plane_no: plane number for which the address is to be returned | |
581 | * | |
582 | * This function returns a kernel virtual address of a given plane if | |
583 | * such a mapping exist, NULL otherwise. | |
584 | */ | |
585 | void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no) | |
586 | { | |
587 | struct vb2_queue *q = vb->vb2_queue; | |
588 | ||
589 | if (plane_no > vb->num_planes) | |
590 | return NULL; | |
591 | ||
592 | return call_memop(q, plane_no, vaddr, vb->planes[plane_no].mem_priv); | |
593 | ||
594 | } | |
595 | EXPORT_SYMBOL_GPL(vb2_plane_vaddr); | |
596 | ||
597 | /** | |
598 | * vb2_plane_cookie() - Return allocator specific cookie for the given plane | |
599 | * @vb: vb2_buffer to which the plane in question belongs to | |
600 | * @plane_no: plane number for which the cookie is to be returned | |
601 | * | |
602 | * This function returns an allocator specific cookie for a given plane if | |
603 | * available, NULL otherwise. The allocator should provide some simple static | |
604 | * inline function, which would convert this cookie to the allocator specific | |
605 | * type that can be used directly by the driver to access the buffer. This can | |
606 | * be for example physical address, pointer to scatter list or IOMMU mapping. | |
607 | */ | |
608 | void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no) | |
609 | { | |
610 | struct vb2_queue *q = vb->vb2_queue; | |
611 | ||
612 | if (plane_no > vb->num_planes) | |
613 | return NULL; | |
614 | ||
615 | return call_memop(q, plane_no, cookie, vb->planes[plane_no].mem_priv); | |
616 | } | |
617 | EXPORT_SYMBOL_GPL(vb2_plane_cookie); | |
618 | ||
619 | /** | |
620 | * vb2_buffer_done() - inform videobuf that an operation on a buffer is finished | |
621 | * @vb: vb2_buffer returned from the driver | |
622 | * @state: either VB2_BUF_STATE_DONE if the operation finished successfully | |
623 | * or VB2_BUF_STATE_ERROR if the operation finished with an error | |
624 | * | |
625 | * This function should be called by the driver after a hardware operation on | |
626 | * a buffer is finished and the buffer may be returned to userspace. The driver | |
627 | * cannot use this buffer anymore until it is queued back to it by videobuf | |
628 | * by the means of buf_queue callback. Only buffers previously queued to the | |
629 | * driver by buf_queue can be passed to this function. | |
630 | */ | |
631 | void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state) | |
632 | { | |
633 | struct vb2_queue *q = vb->vb2_queue; | |
634 | unsigned long flags; | |
635 | ||
636 | if (vb->state != VB2_BUF_STATE_ACTIVE) | |
637 | return; | |
638 | ||
639 | if (state != VB2_BUF_STATE_DONE && state != VB2_BUF_STATE_ERROR) | |
640 | return; | |
641 | ||
642 | dprintk(4, "Done processing on buffer %d, state: %d\n", | |
643 | vb->v4l2_buf.index, vb->state); | |
644 | ||
645 | /* Add the buffer to the done buffers list */ | |
646 | spin_lock_irqsave(&q->done_lock, flags); | |
647 | vb->state = state; | |
648 | list_add_tail(&vb->done_entry, &q->done_list); | |
649 | atomic_dec(&q->queued_count); | |
650 | spin_unlock_irqrestore(&q->done_lock, flags); | |
651 | ||
652 | /* Inform any processes that may be waiting for buffers */ | |
653 | wake_up(&q->done_wq); | |
654 | } | |
655 | EXPORT_SYMBOL_GPL(vb2_buffer_done); | |
656 | ||
657 | /** | |
658 | * __fill_vb2_buffer() - fill a vb2_buffer with information provided in | |
659 | * a v4l2_buffer by the userspace | |
660 | */ | |
661 | static int __fill_vb2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b, | |
662 | struct v4l2_plane *v4l2_planes) | |
663 | { | |
664 | unsigned int plane; | |
665 | int ret; | |
666 | ||
667 | if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) { | |
668 | /* | |
669 | * Verify that the userspace gave us a valid array for | |
670 | * plane information. | |
671 | */ | |
672 | ret = __verify_planes_array(vb, b); | |
673 | if (ret) | |
674 | return ret; | |
675 | ||
676 | /* Fill in driver-provided information for OUTPUT types */ | |
677 | if (V4L2_TYPE_IS_OUTPUT(b->type)) { | |
678 | /* | |
679 | * Will have to go up to b->length when API starts | |
680 | * accepting variable number of planes. | |
681 | */ | |
682 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
683 | v4l2_planes[plane].bytesused = | |
684 | b->m.planes[plane].bytesused; | |
685 | v4l2_planes[plane].data_offset = | |
686 | b->m.planes[plane].data_offset; | |
687 | } | |
688 | } | |
689 | ||
690 | if (b->memory == V4L2_MEMORY_USERPTR) { | |
691 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
692 | v4l2_planes[plane].m.userptr = | |
693 | b->m.planes[plane].m.userptr; | |
694 | v4l2_planes[plane].length = | |
695 | b->m.planes[plane].length; | |
696 | } | |
697 | } | |
698 | } else { | |
699 | /* | |
700 | * Single-planar buffers do not use planes array, | |
701 | * so fill in relevant v4l2_buffer struct fields instead. | |
702 | * In videobuf we use our internal V4l2_planes struct for | |
703 | * single-planar buffers as well, for simplicity. | |
704 | */ | |
705 | if (V4L2_TYPE_IS_OUTPUT(b->type)) | |
706 | v4l2_planes[0].bytesused = b->bytesused; | |
707 | ||
708 | if (b->memory == V4L2_MEMORY_USERPTR) { | |
709 | v4l2_planes[0].m.userptr = b->m.userptr; | |
710 | v4l2_planes[0].length = b->length; | |
711 | } | |
712 | } | |
713 | ||
714 | vb->v4l2_buf.field = b->field; | |
715 | vb->v4l2_buf.timestamp = b->timestamp; | |
ea42c8ec MS |
716 | vb->v4l2_buf.input = b->input; |
717 | vb->v4l2_buf.flags = b->flags & ~V4L2_BUFFER_STATE_FLAGS; | |
e23ccc0a PO |
718 | |
719 | return 0; | |
720 | } | |
721 | ||
722 | /** | |
723 | * __qbuf_userptr() - handle qbuf of a USERPTR buffer | |
724 | */ | |
725 | static int __qbuf_userptr(struct vb2_buffer *vb, struct v4l2_buffer *b) | |
726 | { | |
727 | struct v4l2_plane planes[VIDEO_MAX_PLANES]; | |
728 | struct vb2_queue *q = vb->vb2_queue; | |
729 | void *mem_priv; | |
730 | unsigned int plane; | |
731 | int ret; | |
732 | int write = !V4L2_TYPE_IS_OUTPUT(q->type); | |
733 | ||
734 | /* Verify and copy relevant information provided by the userspace */ | |
735 | ret = __fill_vb2_buffer(vb, b, planes); | |
736 | if (ret) | |
737 | return ret; | |
738 | ||
739 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
740 | /* Skip the plane if already verified */ | |
741 | if (vb->v4l2_planes[plane].m.userptr == planes[plane].m.userptr | |
742 | && vb->v4l2_planes[plane].length == planes[plane].length) | |
743 | continue; | |
744 | ||
745 | dprintk(3, "qbuf: userspace address for plane %d changed, " | |
746 | "reacquiring memory\n", plane); | |
747 | ||
748 | /* Release previously acquired memory if present */ | |
749 | if (vb->planes[plane].mem_priv) | |
750 | call_memop(q, plane, put_userptr, | |
751 | vb->planes[plane].mem_priv); | |
752 | ||
753 | vb->planes[plane].mem_priv = NULL; | |
754 | ||
755 | /* Acquire each plane's memory */ | |
756 | if (q->mem_ops->get_userptr) { | |
757 | mem_priv = q->mem_ops->get_userptr(q->alloc_ctx[plane], | |
758 | planes[plane].m.userptr, | |
759 | planes[plane].length, | |
760 | write); | |
761 | if (IS_ERR(mem_priv)) { | |
762 | dprintk(1, "qbuf: failed acquiring userspace " | |
763 | "memory for plane %d\n", plane); | |
764 | ret = PTR_ERR(mem_priv); | |
765 | goto err; | |
766 | } | |
767 | vb->planes[plane].mem_priv = mem_priv; | |
768 | } | |
769 | } | |
770 | ||
771 | /* | |
772 | * Call driver-specific initialization on the newly acquired buffer, | |
773 | * if provided. | |
774 | */ | |
775 | ret = call_qop(q, buf_init, vb); | |
776 | if (ret) { | |
777 | dprintk(1, "qbuf: buffer initialization failed\n"); | |
778 | goto err; | |
779 | } | |
780 | ||
781 | /* | |
782 | * Now that everything is in order, copy relevant information | |
783 | * provided by userspace. | |
784 | */ | |
785 | for (plane = 0; plane < vb->num_planes; ++plane) | |
786 | vb->v4l2_planes[plane] = planes[plane]; | |
787 | ||
788 | return 0; | |
789 | err: | |
790 | /* In case of errors, release planes that were already acquired */ | |
791 | for (; plane > 0; --plane) { | |
792 | call_memop(q, plane, put_userptr, | |
793 | vb->planes[plane - 1].mem_priv); | |
794 | vb->planes[plane - 1].mem_priv = NULL; | |
795 | } | |
796 | ||
797 | return ret; | |
798 | } | |
799 | ||
800 | /** | |
801 | * __qbuf_mmap() - handle qbuf of an MMAP buffer | |
802 | */ | |
803 | static int __qbuf_mmap(struct vb2_buffer *vb, struct v4l2_buffer *b) | |
804 | { | |
805 | return __fill_vb2_buffer(vb, b, vb->v4l2_planes); | |
806 | } | |
807 | ||
808 | /** | |
809 | * __enqueue_in_driver() - enqueue a vb2_buffer in driver for processing | |
810 | */ | |
811 | static void __enqueue_in_driver(struct vb2_buffer *vb) | |
812 | { | |
813 | struct vb2_queue *q = vb->vb2_queue; | |
814 | ||
815 | vb->state = VB2_BUF_STATE_ACTIVE; | |
816 | atomic_inc(&q->queued_count); | |
817 | q->ops->buf_queue(vb); | |
818 | } | |
819 | ||
820 | /** | |
821 | * vb2_qbuf() - Queue a buffer from userspace | |
822 | * @q: videobuf2 queue | |
823 | * @b: buffer structure passed from userspace to vidioc_qbuf handler | |
824 | * in driver | |
825 | * | |
826 | * Should be called from vidioc_qbuf ioctl handler of a driver. | |
827 | * This function: | |
828 | * 1) verifies the passed buffer, | |
829 | * 2) calls buf_prepare callback in the driver (if provided), in which | |
830 | * driver-specific buffer initialization can be performed, | |
831 | * 3) if streaming is on, queues the buffer in driver by the means of buf_queue | |
832 | * callback for processing. | |
833 | * | |
834 | * The return values from this function are intended to be directly returned | |
835 | * from vidioc_qbuf handler in driver. | |
836 | */ | |
837 | int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b) | |
838 | { | |
839 | struct vb2_buffer *vb; | |
840 | int ret = 0; | |
841 | ||
b25748fe MS |
842 | if (q->fileio) { |
843 | dprintk(1, "qbuf: file io in progress\n"); | |
844 | return -EBUSY; | |
845 | } | |
846 | ||
e23ccc0a PO |
847 | if (b->type != q->type) { |
848 | dprintk(1, "qbuf: invalid buffer type\n"); | |
849 | return -EINVAL; | |
850 | } | |
851 | ||
852 | if (b->index >= q->num_buffers) { | |
853 | dprintk(1, "qbuf: buffer index out of range\n"); | |
854 | return -EINVAL; | |
855 | } | |
856 | ||
857 | vb = q->bufs[b->index]; | |
858 | if (NULL == vb) { | |
859 | /* Should never happen */ | |
860 | dprintk(1, "qbuf: buffer is NULL\n"); | |
861 | return -EINVAL; | |
862 | } | |
863 | ||
864 | if (b->memory != q->memory) { | |
865 | dprintk(1, "qbuf: invalid memory type\n"); | |
866 | return -EINVAL; | |
867 | } | |
868 | ||
869 | if (vb->state != VB2_BUF_STATE_DEQUEUED) { | |
870 | dprintk(1, "qbuf: buffer already in use\n"); | |
871 | return -EINVAL; | |
872 | } | |
873 | ||
874 | if (q->memory == V4L2_MEMORY_MMAP) | |
875 | ret = __qbuf_mmap(vb, b); | |
876 | else if (q->memory == V4L2_MEMORY_USERPTR) | |
877 | ret = __qbuf_userptr(vb, b); | |
878 | else { | |
879 | WARN(1, "Invalid queue type\n"); | |
880 | return -EINVAL; | |
881 | } | |
882 | ||
883 | if (ret) | |
884 | return ret; | |
885 | ||
886 | ret = call_qop(q, buf_prepare, vb); | |
887 | if (ret) { | |
888 | dprintk(1, "qbuf: buffer preparation failed\n"); | |
889 | return ret; | |
890 | } | |
891 | ||
892 | /* | |
893 | * Add to the queued buffers list, a buffer will stay on it until | |
894 | * dequeued in dqbuf. | |
895 | */ | |
896 | list_add_tail(&vb->queued_entry, &q->queued_list); | |
897 | vb->state = VB2_BUF_STATE_QUEUED; | |
898 | ||
899 | /* | |
900 | * If already streaming, give the buffer to driver for processing. | |
901 | * If not, the buffer will be given to driver on next streamon. | |
902 | */ | |
903 | if (q->streaming) | |
904 | __enqueue_in_driver(vb); | |
905 | ||
906 | dprintk(1, "qbuf of buffer %d succeeded\n", vb->v4l2_buf.index); | |
907 | return 0; | |
908 | } | |
909 | EXPORT_SYMBOL_GPL(vb2_qbuf); | |
910 | ||
911 | /** | |
912 | * __vb2_wait_for_done_vb() - wait for a buffer to become available | |
913 | * for dequeuing | |
914 | * | |
915 | * Will sleep if required for nonblocking == false. | |
916 | */ | |
917 | static int __vb2_wait_for_done_vb(struct vb2_queue *q, int nonblocking) | |
918 | { | |
919 | /* | |
920 | * All operations on vb_done_list are performed under done_lock | |
921 | * spinlock protection. However, buffers may be removed from | |
922 | * it and returned to userspace only while holding both driver's | |
923 | * lock and the done_lock spinlock. Thus we can be sure that as | |
924 | * long as we hold the driver's lock, the list will remain not | |
925 | * empty if list_empty() check succeeds. | |
926 | */ | |
927 | ||
928 | for (;;) { | |
929 | int ret; | |
930 | ||
931 | if (!q->streaming) { | |
932 | dprintk(1, "Streaming off, will not wait for buffers\n"); | |
933 | return -EINVAL; | |
934 | } | |
935 | ||
936 | if (!list_empty(&q->done_list)) { | |
937 | /* | |
938 | * Found a buffer that we were waiting for. | |
939 | */ | |
940 | break; | |
941 | } | |
942 | ||
943 | if (nonblocking) { | |
944 | dprintk(1, "Nonblocking and no buffers to dequeue, " | |
945 | "will not wait\n"); | |
946 | return -EAGAIN; | |
947 | } | |
948 | ||
949 | /* | |
950 | * We are streaming and blocking, wait for another buffer to | |
951 | * become ready or for streamoff. Driver's lock is released to | |
952 | * allow streamoff or qbuf to be called while waiting. | |
953 | */ | |
954 | call_qop(q, wait_prepare, q); | |
955 | ||
956 | /* | |
957 | * All locks have been released, it is safe to sleep now. | |
958 | */ | |
959 | dprintk(3, "Will sleep waiting for buffers\n"); | |
960 | ret = wait_event_interruptible(q->done_wq, | |
961 | !list_empty(&q->done_list) || !q->streaming); | |
962 | ||
963 | /* | |
964 | * We need to reevaluate both conditions again after reacquiring | |
965 | * the locks or return an error if one occurred. | |
966 | */ | |
967 | call_qop(q, wait_finish, q); | |
968 | if (ret) | |
969 | return ret; | |
970 | } | |
971 | return 0; | |
972 | } | |
973 | ||
974 | /** | |
975 | * __vb2_get_done_vb() - get a buffer ready for dequeuing | |
976 | * | |
977 | * Will sleep if required for nonblocking == false. | |
978 | */ | |
979 | static int __vb2_get_done_vb(struct vb2_queue *q, struct vb2_buffer **vb, | |
980 | int nonblocking) | |
981 | { | |
982 | unsigned long flags; | |
983 | int ret; | |
984 | ||
985 | /* | |
986 | * Wait for at least one buffer to become available on the done_list. | |
987 | */ | |
988 | ret = __vb2_wait_for_done_vb(q, nonblocking); | |
989 | if (ret) | |
990 | return ret; | |
991 | ||
992 | /* | |
993 | * Driver's lock has been held since we last verified that done_list | |
994 | * is not empty, so no need for another list_empty(done_list) check. | |
995 | */ | |
996 | spin_lock_irqsave(&q->done_lock, flags); | |
997 | *vb = list_first_entry(&q->done_list, struct vb2_buffer, done_entry); | |
998 | list_del(&(*vb)->done_entry); | |
999 | spin_unlock_irqrestore(&q->done_lock, flags); | |
1000 | ||
1001 | return 0; | |
1002 | } | |
1003 | ||
1004 | /** | |
1005 | * vb2_wait_for_all_buffers() - wait until all buffers are given back to vb2 | |
1006 | * @q: videobuf2 queue | |
1007 | * | |
1008 | * This function will wait until all buffers that have been given to the driver | |
1009 | * by buf_queue() are given back to vb2 with vb2_buffer_done(). It doesn't call | |
1010 | * wait_prepare, wait_finish pair. It is intended to be called with all locks | |
1011 | * taken, for example from stop_streaming() callback. | |
1012 | */ | |
1013 | int vb2_wait_for_all_buffers(struct vb2_queue *q) | |
1014 | { | |
1015 | if (!q->streaming) { | |
1016 | dprintk(1, "Streaming off, will not wait for buffers\n"); | |
1017 | return -EINVAL; | |
1018 | } | |
1019 | ||
1020 | wait_event(q->done_wq, !atomic_read(&q->queued_count)); | |
1021 | return 0; | |
1022 | } | |
1023 | EXPORT_SYMBOL_GPL(vb2_wait_for_all_buffers); | |
1024 | ||
1025 | /** | |
1026 | * vb2_dqbuf() - Dequeue a buffer to the userspace | |
1027 | * @q: videobuf2 queue | |
1028 | * @b: buffer structure passed from userspace to vidioc_dqbuf handler | |
1029 | * in driver | |
1030 | * @nonblocking: if true, this call will not sleep waiting for a buffer if no | |
1031 | * buffers ready for dequeuing are present. Normally the driver | |
1032 | * would be passing (file->f_flags & O_NONBLOCK) here | |
1033 | * | |
1034 | * Should be called from vidioc_dqbuf ioctl handler of a driver. | |
1035 | * This function: | |
1036 | * 1) verifies the passed buffer, | |
1037 | * 2) calls buf_finish callback in the driver (if provided), in which | |
1038 | * driver can perform any additional operations that may be required before | |
1039 | * returning the buffer to userspace, such as cache sync, | |
1040 | * 3) the buffer struct members are filled with relevant information for | |
1041 | * the userspace. | |
1042 | * | |
1043 | * The return values from this function are intended to be directly returned | |
1044 | * from vidioc_dqbuf handler in driver. | |
1045 | */ | |
1046 | int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking) | |
1047 | { | |
1048 | struct vb2_buffer *vb = NULL; | |
1049 | int ret; | |
1050 | ||
b25748fe MS |
1051 | if (q->fileio) { |
1052 | dprintk(1, "dqbuf: file io in progress\n"); | |
1053 | return -EBUSY; | |
1054 | } | |
1055 | ||
e23ccc0a PO |
1056 | if (b->type != q->type) { |
1057 | dprintk(1, "dqbuf: invalid buffer type\n"); | |
1058 | return -EINVAL; | |
1059 | } | |
1060 | ||
1061 | ret = __vb2_get_done_vb(q, &vb, nonblocking); | |
1062 | if (ret < 0) { | |
1063 | dprintk(1, "dqbuf: error getting next done buffer\n"); | |
1064 | return ret; | |
1065 | } | |
1066 | ||
1067 | ret = call_qop(q, buf_finish, vb); | |
1068 | if (ret) { | |
1069 | dprintk(1, "dqbuf: buffer finish failed\n"); | |
1070 | return ret; | |
1071 | } | |
1072 | ||
1073 | switch (vb->state) { | |
1074 | case VB2_BUF_STATE_DONE: | |
1075 | dprintk(3, "dqbuf: Returning done buffer\n"); | |
1076 | break; | |
1077 | case VB2_BUF_STATE_ERROR: | |
1078 | dprintk(3, "dqbuf: Returning done buffer with errors\n"); | |
1079 | break; | |
1080 | default: | |
1081 | dprintk(1, "dqbuf: Invalid buffer state\n"); | |
1082 | return -EINVAL; | |
1083 | } | |
1084 | ||
1085 | /* Fill buffer information for the userspace */ | |
1086 | __fill_v4l2_buffer(vb, b); | |
1087 | /* Remove from videobuf queue */ | |
1088 | list_del(&vb->queued_entry); | |
1089 | ||
1090 | dprintk(1, "dqbuf of buffer %d, with state %d\n", | |
1091 | vb->v4l2_buf.index, vb->state); | |
1092 | ||
1093 | vb->state = VB2_BUF_STATE_DEQUEUED; | |
1094 | return 0; | |
1095 | } | |
1096 | EXPORT_SYMBOL_GPL(vb2_dqbuf); | |
1097 | ||
1098 | /** | |
1099 | * vb2_streamon - start streaming | |
1100 | * @q: videobuf2 queue | |
1101 | * @type: type argument passed from userspace to vidioc_streamon handler | |
1102 | * | |
1103 | * Should be called from vidioc_streamon handler of a driver. | |
1104 | * This function: | |
1105 | * 1) verifies current state | |
1106 | * 2) starts streaming and passes any previously queued buffers to the driver | |
1107 | * | |
1108 | * The return values from this function are intended to be directly returned | |
1109 | * from vidioc_streamon handler in the driver. | |
1110 | */ | |
1111 | int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type) | |
1112 | { | |
1113 | struct vb2_buffer *vb; | |
5db2c3ba | 1114 | int ret; |
e23ccc0a | 1115 | |
b25748fe MS |
1116 | if (q->fileio) { |
1117 | dprintk(1, "streamon: file io in progress\n"); | |
1118 | return -EBUSY; | |
1119 | } | |
1120 | ||
e23ccc0a PO |
1121 | if (type != q->type) { |
1122 | dprintk(1, "streamon: invalid stream type\n"); | |
1123 | return -EINVAL; | |
1124 | } | |
1125 | ||
1126 | if (q->streaming) { | |
1127 | dprintk(1, "streamon: already streaming\n"); | |
1128 | return -EBUSY; | |
1129 | } | |
1130 | ||
1131 | /* | |
1132 | * Cannot start streaming on an OUTPUT device if no buffers have | |
1133 | * been queued yet. | |
1134 | */ | |
1135 | if (V4L2_TYPE_IS_OUTPUT(q->type)) { | |
1136 | if (list_empty(&q->queued_list)) { | |
1137 | dprintk(1, "streamon: no output buffers queued\n"); | |
1138 | return -EINVAL; | |
1139 | } | |
1140 | } | |
1141 | ||
e23ccc0a PO |
1142 | /* |
1143 | * Let driver notice that streaming state has been enabled. | |
1144 | */ | |
5db2c3ba PO |
1145 | ret = call_qop(q, start_streaming, q); |
1146 | if (ret) { | |
1147 | dprintk(1, "streamon: driver refused to start streaming\n"); | |
1148 | return ret; | |
1149 | } | |
1150 | ||
1151 | q->streaming = 1; | |
e23ccc0a PO |
1152 | |
1153 | /* | |
1154 | * If any buffers were queued before streamon, | |
1155 | * we can now pass them to driver for processing. | |
1156 | */ | |
1157 | list_for_each_entry(vb, &q->queued_list, queued_entry) | |
1158 | __enqueue_in_driver(vb); | |
1159 | ||
1160 | dprintk(3, "Streamon successful\n"); | |
1161 | return 0; | |
1162 | } | |
1163 | EXPORT_SYMBOL_GPL(vb2_streamon); | |
1164 | ||
1165 | /** | |
1166 | * __vb2_queue_cancel() - cancel and stop (pause) streaming | |
1167 | * | |
1168 | * Removes all queued buffers from driver's queue and all buffers queued by | |
1169 | * userspace from videobuf's queue. Returns to state after reqbufs. | |
1170 | */ | |
1171 | static void __vb2_queue_cancel(struct vb2_queue *q) | |
1172 | { | |
1173 | unsigned int i; | |
1174 | ||
1175 | /* | |
1176 | * Tell driver to stop all transactions and release all queued | |
1177 | * buffers. | |
1178 | */ | |
1179 | if (q->streaming) | |
1180 | call_qop(q, stop_streaming, q); | |
1181 | q->streaming = 0; | |
1182 | ||
1183 | /* | |
1184 | * Remove all buffers from videobuf's list... | |
1185 | */ | |
1186 | INIT_LIST_HEAD(&q->queued_list); | |
1187 | /* | |
1188 | * ...and done list; userspace will not receive any buffers it | |
1189 | * has not already dequeued before initiating cancel. | |
1190 | */ | |
1191 | INIT_LIST_HEAD(&q->done_list); | |
afdea8ba | 1192 | atomic_set(&q->queued_count, 0); |
e23ccc0a PO |
1193 | wake_up_all(&q->done_wq); |
1194 | ||
1195 | /* | |
1196 | * Reinitialize all buffers for next use. | |
1197 | */ | |
1198 | for (i = 0; i < q->num_buffers; ++i) | |
1199 | q->bufs[i]->state = VB2_BUF_STATE_DEQUEUED; | |
1200 | } | |
1201 | ||
1202 | /** | |
1203 | * vb2_streamoff - stop streaming | |
1204 | * @q: videobuf2 queue | |
1205 | * @type: type argument passed from userspace to vidioc_streamoff handler | |
1206 | * | |
1207 | * Should be called from vidioc_streamoff handler of a driver. | |
1208 | * This function: | |
1209 | * 1) verifies current state, | |
1210 | * 2) stop streaming and dequeues any queued buffers, including those previously | |
1211 | * passed to the driver (after waiting for the driver to finish). | |
1212 | * | |
1213 | * This call can be used for pausing playback. | |
1214 | * The return values from this function are intended to be directly returned | |
1215 | * from vidioc_streamoff handler in the driver | |
1216 | */ | |
1217 | int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type) | |
1218 | { | |
b25748fe MS |
1219 | if (q->fileio) { |
1220 | dprintk(1, "streamoff: file io in progress\n"); | |
1221 | return -EBUSY; | |
1222 | } | |
1223 | ||
e23ccc0a PO |
1224 | if (type != q->type) { |
1225 | dprintk(1, "streamoff: invalid stream type\n"); | |
1226 | return -EINVAL; | |
1227 | } | |
1228 | ||
1229 | if (!q->streaming) { | |
1230 | dprintk(1, "streamoff: not streaming\n"); | |
1231 | return -EINVAL; | |
1232 | } | |
1233 | ||
1234 | /* | |
1235 | * Cancel will pause streaming and remove all buffers from the driver | |
1236 | * and videobuf, effectively returning control over them to userspace. | |
1237 | */ | |
1238 | __vb2_queue_cancel(q); | |
1239 | ||
1240 | dprintk(3, "Streamoff successful\n"); | |
1241 | return 0; | |
1242 | } | |
1243 | EXPORT_SYMBOL_GPL(vb2_streamoff); | |
1244 | ||
1245 | /** | |
1246 | * __find_plane_by_offset() - find plane associated with the given offset off | |
1247 | */ | |
1248 | static int __find_plane_by_offset(struct vb2_queue *q, unsigned long off, | |
1249 | unsigned int *_buffer, unsigned int *_plane) | |
1250 | { | |
1251 | struct vb2_buffer *vb; | |
1252 | unsigned int buffer, plane; | |
1253 | ||
1254 | /* | |
1255 | * Go over all buffers and their planes, comparing the given offset | |
1256 | * with an offset assigned to each plane. If a match is found, | |
1257 | * return its buffer and plane numbers. | |
1258 | */ | |
1259 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
1260 | vb = q->bufs[buffer]; | |
1261 | ||
1262 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
1263 | if (vb->v4l2_planes[plane].m.mem_offset == off) { | |
1264 | *_buffer = buffer; | |
1265 | *_plane = plane; | |
1266 | return 0; | |
1267 | } | |
1268 | } | |
1269 | } | |
1270 | ||
1271 | return -EINVAL; | |
1272 | } | |
1273 | ||
1274 | /** | |
1275 | * vb2_mmap() - map video buffers into application address space | |
1276 | * @q: videobuf2 queue | |
1277 | * @vma: vma passed to the mmap file operation handler in the driver | |
1278 | * | |
1279 | * Should be called from mmap file operation handler of a driver. | |
1280 | * This function maps one plane of one of the available video buffers to | |
1281 | * userspace. To map whole video memory allocated on reqbufs, this function | |
1282 | * has to be called once per each plane per each buffer previously allocated. | |
1283 | * | |
1284 | * When the userspace application calls mmap, it passes to it an offset returned | |
1285 | * to it earlier by the means of vidioc_querybuf handler. That offset acts as | |
1286 | * a "cookie", which is then used to identify the plane to be mapped. | |
1287 | * This function finds a plane with a matching offset and a mapping is performed | |
1288 | * by the means of a provided memory operation. | |
1289 | * | |
1290 | * The return values from this function are intended to be directly returned | |
1291 | * from the mmap handler in driver. | |
1292 | */ | |
1293 | int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma) | |
1294 | { | |
1295 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
1296 | struct vb2_plane *vb_plane; | |
1297 | struct vb2_buffer *vb; | |
1298 | unsigned int buffer, plane; | |
1299 | int ret; | |
1300 | ||
1301 | if (q->memory != V4L2_MEMORY_MMAP) { | |
1302 | dprintk(1, "Queue is not currently set up for mmap\n"); | |
1303 | return -EINVAL; | |
1304 | } | |
1305 | ||
1306 | /* | |
1307 | * Check memory area access mode. | |
1308 | */ | |
1309 | if (!(vma->vm_flags & VM_SHARED)) { | |
1310 | dprintk(1, "Invalid vma flags, VM_SHARED needed\n"); | |
1311 | return -EINVAL; | |
1312 | } | |
1313 | if (V4L2_TYPE_IS_OUTPUT(q->type)) { | |
1314 | if (!(vma->vm_flags & VM_WRITE)) { | |
1315 | dprintk(1, "Invalid vma flags, VM_WRITE needed\n"); | |
1316 | return -EINVAL; | |
1317 | } | |
1318 | } else { | |
1319 | if (!(vma->vm_flags & VM_READ)) { | |
1320 | dprintk(1, "Invalid vma flags, VM_READ needed\n"); | |
1321 | return -EINVAL; | |
1322 | } | |
1323 | } | |
1324 | ||
1325 | /* | |
1326 | * Find the plane corresponding to the offset passed by userspace. | |
1327 | */ | |
1328 | ret = __find_plane_by_offset(q, off, &buffer, &plane); | |
1329 | if (ret) | |
1330 | return ret; | |
1331 | ||
1332 | vb = q->bufs[buffer]; | |
1333 | vb_plane = &vb->planes[plane]; | |
1334 | ||
1335 | ret = q->mem_ops->mmap(vb_plane->mem_priv, vma); | |
1336 | if (ret) | |
1337 | return ret; | |
1338 | ||
1339 | vb_plane->mapped = 1; | |
1340 | vb->num_planes_mapped++; | |
1341 | ||
1342 | dprintk(3, "Buffer %d, plane %d successfully mapped\n", buffer, plane); | |
1343 | return 0; | |
1344 | } | |
1345 | EXPORT_SYMBOL_GPL(vb2_mmap); | |
1346 | ||
b25748fe MS |
1347 | static int __vb2_init_fileio(struct vb2_queue *q, int read); |
1348 | static int __vb2_cleanup_fileio(struct vb2_queue *q); | |
e23ccc0a PO |
1349 | |
1350 | /** | |
1351 | * vb2_poll() - implements poll userspace operation | |
1352 | * @q: videobuf2 queue | |
1353 | * @file: file argument passed to the poll file operation handler | |
1354 | * @wait: wait argument passed to the poll file operation handler | |
1355 | * | |
1356 | * This function implements poll file operation handler for a driver. | |
1357 | * For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will | |
1358 | * be informed that the file descriptor of a video device is available for | |
1359 | * reading. | |
1360 | * For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor | |
1361 | * will be reported as available for writing. | |
1362 | * | |
1363 | * The return values from this function are intended to be directly returned | |
1364 | * from poll handler in driver. | |
1365 | */ | |
1366 | unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait) | |
1367 | { | |
1368 | unsigned long flags; | |
b25748fe | 1369 | unsigned int ret; |
e23ccc0a PO |
1370 | struct vb2_buffer *vb = NULL; |
1371 | ||
b25748fe | 1372 | /* |
4ffabdb3 | 1373 | * Start file I/O emulator only if streaming API has not been used yet. |
b25748fe MS |
1374 | */ |
1375 | if (q->num_buffers == 0 && q->fileio == NULL) { | |
1376 | if (!V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_READ)) { | |
1377 | ret = __vb2_init_fileio(q, 1); | |
1378 | if (ret) | |
4ffabdb3 | 1379 | return POLLERR; |
b25748fe MS |
1380 | } |
1381 | if (V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_WRITE)) { | |
1382 | ret = __vb2_init_fileio(q, 0); | |
1383 | if (ret) | |
4ffabdb3 | 1384 | return POLLERR; |
b25748fe MS |
1385 | /* |
1386 | * Write to OUTPUT queue can be done immediately. | |
1387 | */ | |
1388 | return POLLOUT | POLLWRNORM; | |
1389 | } | |
1390 | } | |
1391 | ||
e23ccc0a PO |
1392 | /* |
1393 | * There is nothing to wait for if no buffers have already been queued. | |
1394 | */ | |
1395 | if (list_empty(&q->queued_list)) | |
1396 | return POLLERR; | |
1397 | ||
1398 | poll_wait(file, &q->done_wq, wait); | |
1399 | ||
1400 | /* | |
1401 | * Take first buffer available for dequeuing. | |
1402 | */ | |
1403 | spin_lock_irqsave(&q->done_lock, flags); | |
1404 | if (!list_empty(&q->done_list)) | |
1405 | vb = list_first_entry(&q->done_list, struct vb2_buffer, | |
1406 | done_entry); | |
1407 | spin_unlock_irqrestore(&q->done_lock, flags); | |
1408 | ||
1409 | if (vb && (vb->state == VB2_BUF_STATE_DONE | |
1410 | || vb->state == VB2_BUF_STATE_ERROR)) { | |
1411 | return (V4L2_TYPE_IS_OUTPUT(q->type)) ? POLLOUT | POLLWRNORM : | |
1412 | POLLIN | POLLRDNORM; | |
1413 | } | |
1414 | return 0; | |
1415 | } | |
1416 | EXPORT_SYMBOL_GPL(vb2_poll); | |
1417 | ||
1418 | /** | |
1419 | * vb2_queue_init() - initialize a videobuf2 queue | |
1420 | * @q: videobuf2 queue; this structure should be allocated in driver | |
1421 | * | |
1422 | * The vb2_queue structure should be allocated by the driver. The driver is | |
1423 | * responsible of clearing it's content and setting initial values for some | |
1424 | * required entries before calling this function. | |
1425 | * q->ops, q->mem_ops, q->type and q->io_modes are mandatory. Please refer | |
1426 | * to the struct vb2_queue description in include/media/videobuf2-core.h | |
1427 | * for more information. | |
1428 | */ | |
1429 | int vb2_queue_init(struct vb2_queue *q) | |
1430 | { | |
1431 | BUG_ON(!q); | |
1432 | BUG_ON(!q->ops); | |
1433 | BUG_ON(!q->mem_ops); | |
1434 | BUG_ON(!q->type); | |
1435 | BUG_ON(!q->io_modes); | |
1436 | ||
1437 | BUG_ON(!q->ops->queue_setup); | |
1438 | BUG_ON(!q->ops->buf_queue); | |
1439 | ||
1440 | INIT_LIST_HEAD(&q->queued_list); | |
1441 | INIT_LIST_HEAD(&q->done_list); | |
1442 | spin_lock_init(&q->done_lock); | |
1443 | init_waitqueue_head(&q->done_wq); | |
1444 | ||
1445 | if (q->buf_struct_size == 0) | |
1446 | q->buf_struct_size = sizeof(struct vb2_buffer); | |
1447 | ||
1448 | return 0; | |
1449 | } | |
1450 | EXPORT_SYMBOL_GPL(vb2_queue_init); | |
1451 | ||
1452 | /** | |
1453 | * vb2_queue_release() - stop streaming, release the queue and free memory | |
1454 | * @q: videobuf2 queue | |
1455 | * | |
1456 | * This function stops streaming and performs necessary clean ups, including | |
1457 | * freeing video buffer memory. The driver is responsible for freeing | |
1458 | * the vb2_queue structure itself. | |
1459 | */ | |
1460 | void vb2_queue_release(struct vb2_queue *q) | |
1461 | { | |
b25748fe | 1462 | __vb2_cleanup_fileio(q); |
e23ccc0a PO |
1463 | __vb2_queue_cancel(q); |
1464 | __vb2_queue_free(q); | |
1465 | } | |
1466 | EXPORT_SYMBOL_GPL(vb2_queue_release); | |
1467 | ||
b25748fe MS |
1468 | /** |
1469 | * struct vb2_fileio_buf - buffer context used by file io emulator | |
1470 | * | |
1471 | * vb2 provides a compatibility layer and emulator of file io (read and | |
1472 | * write) calls on top of streaming API. This structure is used for | |
1473 | * tracking context related to the buffers. | |
1474 | */ | |
1475 | struct vb2_fileio_buf { | |
1476 | void *vaddr; | |
1477 | unsigned int size; | |
1478 | unsigned int pos; | |
1479 | unsigned int queued:1; | |
1480 | }; | |
1481 | ||
1482 | /** | |
1483 | * struct vb2_fileio_data - queue context used by file io emulator | |
1484 | * | |
1485 | * vb2 provides a compatibility layer and emulator of file io (read and | |
1486 | * write) calls on top of streaming API. For proper operation it required | |
1487 | * this structure to save the driver state between each call of the read | |
1488 | * or write function. | |
1489 | */ | |
1490 | struct vb2_fileio_data { | |
1491 | struct v4l2_requestbuffers req; | |
1492 | struct v4l2_buffer b; | |
1493 | struct vb2_fileio_buf bufs[VIDEO_MAX_FRAME]; | |
1494 | unsigned int index; | |
1495 | unsigned int q_count; | |
1496 | unsigned int dq_count; | |
1497 | unsigned int flags; | |
1498 | }; | |
1499 | ||
1500 | /** | |
1501 | * __vb2_init_fileio() - initialize file io emulator | |
1502 | * @q: videobuf2 queue | |
1503 | * @read: mode selector (1 means read, 0 means write) | |
1504 | */ | |
1505 | static int __vb2_init_fileio(struct vb2_queue *q, int read) | |
1506 | { | |
1507 | struct vb2_fileio_data *fileio; | |
1508 | int i, ret; | |
1509 | unsigned int count = 0; | |
1510 | ||
1511 | /* | |
1512 | * Sanity check | |
1513 | */ | |
1514 | if ((read && !(q->io_modes & VB2_READ)) || | |
1515 | (!read && !(q->io_modes & VB2_WRITE))) | |
1516 | BUG(); | |
1517 | ||
1518 | /* | |
1519 | * Check if device supports mapping buffers to kernel virtual space. | |
1520 | */ | |
1521 | if (!q->mem_ops->vaddr) | |
1522 | return -EBUSY; | |
1523 | ||
1524 | /* | |
1525 | * Check if streaming api has not been already activated. | |
1526 | */ | |
1527 | if (q->streaming || q->num_buffers > 0) | |
1528 | return -EBUSY; | |
1529 | ||
1530 | /* | |
1531 | * Start with count 1, driver can increase it in queue_setup() | |
1532 | */ | |
1533 | count = 1; | |
1534 | ||
1535 | dprintk(3, "setting up file io: mode %s, count %d, flags %08x\n", | |
1536 | (read) ? "read" : "write", count, q->io_flags); | |
1537 | ||
1538 | fileio = kzalloc(sizeof(struct vb2_fileio_data), GFP_KERNEL); | |
1539 | if (fileio == NULL) | |
1540 | return -ENOMEM; | |
1541 | ||
1542 | fileio->flags = q->io_flags; | |
1543 | ||
1544 | /* | |
1545 | * Request buffers and use MMAP type to force driver | |
1546 | * to allocate buffers by itself. | |
1547 | */ | |
1548 | fileio->req.count = count; | |
1549 | fileio->req.memory = V4L2_MEMORY_MMAP; | |
1550 | fileio->req.type = q->type; | |
1551 | ret = vb2_reqbufs(q, &fileio->req); | |
1552 | if (ret) | |
1553 | goto err_kfree; | |
1554 | ||
1555 | /* | |
1556 | * Check if plane_count is correct | |
1557 | * (multiplane buffers are not supported). | |
1558 | */ | |
1559 | if (q->bufs[0]->num_planes != 1) { | |
1560 | fileio->req.count = 0; | |
1561 | ret = -EBUSY; | |
1562 | goto err_reqbufs; | |
1563 | } | |
1564 | ||
1565 | /* | |
1566 | * Get kernel address of each buffer. | |
1567 | */ | |
1568 | for (i = 0; i < q->num_buffers; i++) { | |
1569 | fileio->bufs[i].vaddr = vb2_plane_vaddr(q->bufs[i], 0); | |
1570 | if (fileio->bufs[i].vaddr == NULL) | |
1571 | goto err_reqbufs; | |
1572 | fileio->bufs[i].size = vb2_plane_size(q->bufs[i], 0); | |
1573 | } | |
1574 | ||
1575 | /* | |
1576 | * Read mode requires pre queuing of all buffers. | |
1577 | */ | |
1578 | if (read) { | |
1579 | /* | |
1580 | * Queue all buffers. | |
1581 | */ | |
1582 | for (i = 0; i < q->num_buffers; i++) { | |
1583 | struct v4l2_buffer *b = &fileio->b; | |
1584 | memset(b, 0, sizeof(*b)); | |
1585 | b->type = q->type; | |
1586 | b->memory = q->memory; | |
1587 | b->index = i; | |
1588 | ret = vb2_qbuf(q, b); | |
1589 | if (ret) | |
1590 | goto err_reqbufs; | |
1591 | fileio->bufs[i].queued = 1; | |
1592 | } | |
1593 | ||
1594 | /* | |
1595 | * Start streaming. | |
1596 | */ | |
1597 | ret = vb2_streamon(q, q->type); | |
1598 | if (ret) | |
1599 | goto err_reqbufs; | |
1600 | } | |
1601 | ||
1602 | q->fileio = fileio; | |
1603 | ||
1604 | return ret; | |
1605 | ||
1606 | err_reqbufs: | |
1607 | vb2_reqbufs(q, &fileio->req); | |
1608 | ||
1609 | err_kfree: | |
1610 | kfree(fileio); | |
1611 | return ret; | |
1612 | } | |
1613 | ||
1614 | /** | |
1615 | * __vb2_cleanup_fileio() - free resourced used by file io emulator | |
1616 | * @q: videobuf2 queue | |
1617 | */ | |
1618 | static int __vb2_cleanup_fileio(struct vb2_queue *q) | |
1619 | { | |
1620 | struct vb2_fileio_data *fileio = q->fileio; | |
1621 | ||
1622 | if (fileio) { | |
1623 | /* | |
1624 | * Hack fileio context to enable direct calls to vb2 ioctl | |
1625 | * interface. | |
1626 | */ | |
1627 | q->fileio = NULL; | |
1628 | ||
1629 | vb2_streamoff(q, q->type); | |
1630 | fileio->req.count = 0; | |
1631 | vb2_reqbufs(q, &fileio->req); | |
1632 | kfree(fileio); | |
1633 | dprintk(3, "file io emulator closed\n"); | |
1634 | } | |
1635 | return 0; | |
1636 | } | |
1637 | ||
1638 | /** | |
1639 | * __vb2_perform_fileio() - perform a single file io (read or write) operation | |
1640 | * @q: videobuf2 queue | |
1641 | * @data: pointed to target userspace buffer | |
1642 | * @count: number of bytes to read or write | |
1643 | * @ppos: file handle position tracking pointer | |
1644 | * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) | |
1645 | * @read: access mode selector (1 means read, 0 means write) | |
1646 | */ | |
1647 | static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_t count, | |
1648 | loff_t *ppos, int nonblock, int read) | |
1649 | { | |
1650 | struct vb2_fileio_data *fileio; | |
1651 | struct vb2_fileio_buf *buf; | |
1652 | int ret, index; | |
1653 | ||
08b99e26 | 1654 | dprintk(3, "file io: mode %s, offset %ld, count %zd, %sblocking\n", |
b25748fe MS |
1655 | read ? "read" : "write", (long)*ppos, count, |
1656 | nonblock ? "non" : ""); | |
1657 | ||
1658 | if (!data) | |
1659 | return -EINVAL; | |
1660 | ||
1661 | /* | |
1662 | * Initialize emulator on first call. | |
1663 | */ | |
1664 | if (!q->fileio) { | |
1665 | ret = __vb2_init_fileio(q, read); | |
1666 | dprintk(3, "file io: vb2_init_fileio result: %d\n", ret); | |
1667 | if (ret) | |
1668 | return ret; | |
1669 | } | |
1670 | fileio = q->fileio; | |
1671 | ||
1672 | /* | |
1673 | * Hack fileio context to enable direct calls to vb2 ioctl interface. | |
1674 | * The pointer will be restored before returning from this function. | |
1675 | */ | |
1676 | q->fileio = NULL; | |
1677 | ||
1678 | index = fileio->index; | |
1679 | buf = &fileio->bufs[index]; | |
1680 | ||
1681 | /* | |
1682 | * Check if we need to dequeue the buffer. | |
1683 | */ | |
1684 | if (buf->queued) { | |
1685 | struct vb2_buffer *vb; | |
1686 | ||
1687 | /* | |
1688 | * Call vb2_dqbuf to get buffer back. | |
1689 | */ | |
1690 | memset(&fileio->b, 0, sizeof(fileio->b)); | |
1691 | fileio->b.type = q->type; | |
1692 | fileio->b.memory = q->memory; | |
1693 | fileio->b.index = index; | |
1694 | ret = vb2_dqbuf(q, &fileio->b, nonblock); | |
1695 | dprintk(5, "file io: vb2_dqbuf result: %d\n", ret); | |
1696 | if (ret) | |
1697 | goto end; | |
1698 | fileio->dq_count += 1; | |
1699 | ||
1700 | /* | |
1701 | * Get number of bytes filled by the driver | |
1702 | */ | |
1703 | vb = q->bufs[index]; | |
1704 | buf->size = vb2_get_plane_payload(vb, 0); | |
1705 | buf->queued = 0; | |
1706 | } | |
1707 | ||
1708 | /* | |
1709 | * Limit count on last few bytes of the buffer. | |
1710 | */ | |
1711 | if (buf->pos + count > buf->size) { | |
1712 | count = buf->size - buf->pos; | |
08b99e26 | 1713 | dprintk(5, "reducing read count: %zd\n", count); |
b25748fe MS |
1714 | } |
1715 | ||
1716 | /* | |
1717 | * Transfer data to userspace. | |
1718 | */ | |
08b99e26 | 1719 | dprintk(3, "file io: copying %zd bytes - buffer %d, offset %u\n", |
b25748fe MS |
1720 | count, index, buf->pos); |
1721 | if (read) | |
1722 | ret = copy_to_user(data, buf->vaddr + buf->pos, count); | |
1723 | else | |
1724 | ret = copy_from_user(buf->vaddr + buf->pos, data, count); | |
1725 | if (ret) { | |
1726 | dprintk(3, "file io: error copying data\n"); | |
1727 | ret = -EFAULT; | |
1728 | goto end; | |
1729 | } | |
1730 | ||
1731 | /* | |
1732 | * Update counters. | |
1733 | */ | |
1734 | buf->pos += count; | |
1735 | *ppos += count; | |
1736 | ||
1737 | /* | |
1738 | * Queue next buffer if required. | |
1739 | */ | |
1740 | if (buf->pos == buf->size || | |
1741 | (!read && (fileio->flags & VB2_FILEIO_WRITE_IMMEDIATELY))) { | |
1742 | /* | |
1743 | * Check if this is the last buffer to read. | |
1744 | */ | |
1745 | if (read && (fileio->flags & VB2_FILEIO_READ_ONCE) && | |
1746 | fileio->dq_count == 1) { | |
1747 | dprintk(3, "file io: read limit reached\n"); | |
1748 | /* | |
1749 | * Restore fileio pointer and release the context. | |
1750 | */ | |
1751 | q->fileio = fileio; | |
1752 | return __vb2_cleanup_fileio(q); | |
1753 | } | |
1754 | ||
1755 | /* | |
1756 | * Call vb2_qbuf and give buffer to the driver. | |
1757 | */ | |
1758 | memset(&fileio->b, 0, sizeof(fileio->b)); | |
1759 | fileio->b.type = q->type; | |
1760 | fileio->b.memory = q->memory; | |
1761 | fileio->b.index = index; | |
1762 | fileio->b.bytesused = buf->pos; | |
1763 | ret = vb2_qbuf(q, &fileio->b); | |
1764 | dprintk(5, "file io: vb2_dbuf result: %d\n", ret); | |
1765 | if (ret) | |
1766 | goto end; | |
1767 | ||
1768 | /* | |
1769 | * Buffer has been queued, update the status | |
1770 | */ | |
1771 | buf->pos = 0; | |
1772 | buf->queued = 1; | |
1773 | buf->size = q->bufs[0]->v4l2_planes[0].length; | |
1774 | fileio->q_count += 1; | |
1775 | ||
1776 | /* | |
1777 | * Switch to the next buffer | |
1778 | */ | |
1779 | fileio->index = (index + 1) % q->num_buffers; | |
1780 | ||
1781 | /* | |
1782 | * Start streaming if required. | |
1783 | */ | |
1784 | if (!read && !q->streaming) { | |
1785 | ret = vb2_streamon(q, q->type); | |
1786 | if (ret) | |
1787 | goto end; | |
1788 | } | |
1789 | } | |
1790 | ||
1791 | /* | |
1792 | * Return proper number of bytes processed. | |
1793 | */ | |
1794 | if (ret == 0) | |
1795 | ret = count; | |
1796 | end: | |
1797 | /* | |
1798 | * Restore the fileio context and block vb2 ioctl interface. | |
1799 | */ | |
1800 | q->fileio = fileio; | |
1801 | return ret; | |
1802 | } | |
1803 | ||
1804 | size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, | |
1805 | loff_t *ppos, int nonblocking) | |
1806 | { | |
1807 | return __vb2_perform_fileio(q, data, count, ppos, nonblocking, 1); | |
1808 | } | |
1809 | EXPORT_SYMBOL_GPL(vb2_read); | |
1810 | ||
1811 | size_t vb2_write(struct vb2_queue *q, char __user *data, size_t count, | |
1812 | loff_t *ppos, int nonblocking) | |
1813 | { | |
1814 | return __vb2_perform_fileio(q, data, count, ppos, nonblocking, 0); | |
1815 | } | |
1816 | EXPORT_SYMBOL_GPL(vb2_write); | |
1817 | ||
e23ccc0a | 1818 | MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2"); |
95072084 | 1819 | MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski"); |
e23ccc0a | 1820 | MODULE_LICENSE("GPL"); |