Commit | Line | Data |
---|---|---|
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 | */ | |
c1426bc7 | 46 | static int __vb2_buf_mem_alloc(struct vb2_buffer *vb) |
e23ccc0a PO |
47 | { |
48 | struct vb2_queue *q = vb->vb2_queue; | |
49 | void *mem_priv; | |
50 | int plane; | |
51 | ||
52 | /* Allocate memory for all planes in this buffer */ | |
53 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
54 | mem_priv = call_memop(q, plane, alloc, q->alloc_ctx[plane], | |
c1426bc7 | 55 | q->plane_sizes[plane]); |
62a79436 | 56 | if (IS_ERR_OR_NULL(mem_priv)) |
e23ccc0a PO |
57 | goto free; |
58 | ||
59 | /* Associate allocator private data with this plane */ | |
60 | vb->planes[plane].mem_priv = mem_priv; | |
c1426bc7 | 61 | vb->v4l2_planes[plane].length = q->plane_sizes[plane]; |
e23ccc0a PO |
62 | } |
63 | ||
64 | return 0; | |
65 | free: | |
66 | /* Free already allocated memory if one of the allocations failed */ | |
67 | for (; plane > 0; --plane) | |
68 | call_memop(q, plane, put, vb->planes[plane - 1].mem_priv); | |
69 | ||
70 | return -ENOMEM; | |
71 | } | |
72 | ||
73 | /** | |
74 | * __vb2_buf_mem_free() - free memory of the given buffer | |
75 | */ | |
76 | static void __vb2_buf_mem_free(struct vb2_buffer *vb) | |
77 | { | |
78 | struct vb2_queue *q = vb->vb2_queue; | |
79 | unsigned int plane; | |
80 | ||
81 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
82 | call_memop(q, plane, put, vb->planes[plane].mem_priv); | |
83 | vb->planes[plane].mem_priv = NULL; | |
84 | dprintk(3, "Freed plane %d of buffer %d\n", | |
85 | plane, vb->v4l2_buf.index); | |
86 | } | |
87 | } | |
88 | ||
89 | /** | |
90 | * __vb2_buf_userptr_put() - release userspace memory associated with | |
91 | * a USERPTR buffer | |
92 | */ | |
93 | static void __vb2_buf_userptr_put(struct vb2_buffer *vb) | |
94 | { | |
95 | struct vb2_queue *q = vb->vb2_queue; | |
96 | unsigned int plane; | |
97 | ||
98 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
99 | void *mem_priv = vb->planes[plane].mem_priv; | |
100 | ||
101 | if (mem_priv) { | |
102 | call_memop(q, plane, put_userptr, mem_priv); | |
103 | vb->planes[plane].mem_priv = NULL; | |
104 | } | |
105 | } | |
106 | } | |
107 | ||
108 | /** | |
109 | * __setup_offsets() - setup unique offsets ("cookies") for every plane in | |
110 | * every buffer on the queue | |
111 | */ | |
112 | static void __setup_offsets(struct vb2_queue *q) | |
113 | { | |
114 | unsigned int buffer, plane; | |
115 | struct vb2_buffer *vb; | |
116 | unsigned long off = 0; | |
117 | ||
118 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
119 | vb = q->bufs[buffer]; | |
120 | if (!vb) | |
121 | continue; | |
122 | ||
123 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
124 | vb->v4l2_planes[plane].m.mem_offset = off; | |
125 | ||
126 | dprintk(3, "Buffer %d, plane %d offset 0x%08lx\n", | |
127 | buffer, plane, off); | |
128 | ||
129 | off += vb->v4l2_planes[plane].length; | |
130 | off = PAGE_ALIGN(off); | |
131 | } | |
132 | } | |
133 | } | |
134 | ||
135 | /** | |
136 | * __vb2_queue_alloc() - allocate videobuf buffer structures and (for MMAP type) | |
137 | * video buffer memory for all buffers/planes on the queue and initializes the | |
138 | * queue | |
139 | * | |
140 | * Returns the number of buffers successfully allocated. | |
141 | */ | |
142 | static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory, | |
c1426bc7 | 143 | unsigned int num_buffers, unsigned int num_planes) |
e23ccc0a PO |
144 | { |
145 | unsigned int buffer; | |
146 | struct vb2_buffer *vb; | |
147 | int ret; | |
148 | ||
149 | for (buffer = 0; buffer < num_buffers; ++buffer) { | |
150 | /* Allocate videobuf buffer structures */ | |
151 | vb = kzalloc(q->buf_struct_size, GFP_KERNEL); | |
152 | if (!vb) { | |
153 | dprintk(1, "Memory alloc for buffer struct failed\n"); | |
154 | break; | |
155 | } | |
156 | ||
157 | /* Length stores number of planes for multiplanar buffers */ | |
158 | if (V4L2_TYPE_IS_MULTIPLANAR(q->type)) | |
159 | vb->v4l2_buf.length = num_planes; | |
160 | ||
161 | vb->state = VB2_BUF_STATE_DEQUEUED; | |
162 | vb->vb2_queue = q; | |
163 | vb->num_planes = num_planes; | |
164 | vb->v4l2_buf.index = buffer; | |
165 | vb->v4l2_buf.type = q->type; | |
166 | vb->v4l2_buf.memory = memory; | |
167 | ||
168 | /* Allocate video buffer memory for the MMAP type */ | |
169 | if (memory == V4L2_MEMORY_MMAP) { | |
c1426bc7 | 170 | ret = __vb2_buf_mem_alloc(vb); |
e23ccc0a PO |
171 | if (ret) { |
172 | dprintk(1, "Failed allocating memory for " | |
173 | "buffer %d\n", buffer); | |
174 | kfree(vb); | |
175 | break; | |
176 | } | |
177 | /* | |
178 | * Call the driver-provided buffer initialization | |
179 | * callback, if given. An error in initialization | |
180 | * results in queue setup failure. | |
181 | */ | |
182 | ret = call_qop(q, buf_init, vb); | |
183 | if (ret) { | |
184 | dprintk(1, "Buffer %d %p initialization" | |
185 | " failed\n", buffer, vb); | |
186 | __vb2_buf_mem_free(vb); | |
187 | kfree(vb); | |
188 | break; | |
189 | } | |
190 | } | |
191 | ||
192 | q->bufs[buffer] = vb; | |
193 | } | |
194 | ||
195 | q->num_buffers = buffer; | |
196 | ||
197 | __setup_offsets(q); | |
198 | ||
199 | dprintk(1, "Allocated %d buffers, %d plane(s) each\n", | |
200 | q->num_buffers, num_planes); | |
201 | ||
202 | return buffer; | |
203 | } | |
204 | ||
205 | /** | |
206 | * __vb2_free_mem() - release all video buffer memory for a given queue | |
207 | */ | |
208 | static void __vb2_free_mem(struct vb2_queue *q) | |
209 | { | |
210 | unsigned int buffer; | |
211 | struct vb2_buffer *vb; | |
212 | ||
213 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
214 | vb = q->bufs[buffer]; | |
215 | if (!vb) | |
216 | continue; | |
217 | ||
218 | /* Free MMAP buffers or release USERPTR buffers */ | |
219 | if (q->memory == V4L2_MEMORY_MMAP) | |
220 | __vb2_buf_mem_free(vb); | |
221 | else | |
222 | __vb2_buf_userptr_put(vb); | |
223 | } | |
224 | } | |
225 | ||
226 | /** | |
227 | * __vb2_queue_free() - free the queue - video memory and related information | |
228 | * and return the queue to an uninitialized state. Might be called even if the | |
229 | * queue has already been freed. | |
230 | */ | |
72f1fc33 | 231 | static void __vb2_queue_free(struct vb2_queue *q) |
e23ccc0a PO |
232 | { |
233 | unsigned int buffer; | |
234 | ||
235 | /* Call driver-provided cleanup function for each buffer, if provided */ | |
236 | if (q->ops->buf_cleanup) { | |
237 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
238 | if (NULL == q->bufs[buffer]) | |
239 | continue; | |
240 | q->ops->buf_cleanup(q->bufs[buffer]); | |
241 | } | |
242 | } | |
243 | ||
244 | /* Release video buffer memory */ | |
245 | __vb2_free_mem(q); | |
246 | ||
247 | /* Free videobuf buffers */ | |
248 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
249 | kfree(q->bufs[buffer]); | |
250 | q->bufs[buffer] = NULL; | |
251 | } | |
252 | ||
253 | q->num_buffers = 0; | |
254 | q->memory = 0; | |
e23ccc0a PO |
255 | } |
256 | ||
257 | /** | |
258 | * __verify_planes_array() - verify that the planes array passed in struct | |
259 | * v4l2_buffer from userspace can be safely used | |
260 | */ | |
261 | static int __verify_planes_array(struct vb2_buffer *vb, struct v4l2_buffer *b) | |
262 | { | |
263 | /* Is memory for copying plane information present? */ | |
264 | if (NULL == b->m.planes) { | |
265 | dprintk(1, "Multi-planar buffer passed but " | |
266 | "planes array not provided\n"); | |
267 | return -EINVAL; | |
268 | } | |
269 | ||
270 | if (b->length < vb->num_planes || b->length > VIDEO_MAX_PLANES) { | |
271 | dprintk(1, "Incorrect planes array length, " | |
272 | "expected %d, got %d\n", vb->num_planes, b->length); | |
273 | return -EINVAL; | |
274 | } | |
275 | ||
276 | return 0; | |
277 | } | |
278 | ||
25a27d91 MS |
279 | /** |
280 | * __buffer_in_use() - return true if the buffer is in use and | |
281 | * the queue cannot be freed (by the means of REQBUFS(0)) call | |
282 | */ | |
283 | static bool __buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb) | |
284 | { | |
285 | unsigned int plane; | |
286 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
287 | /* | |
288 | * If num_users() has not been provided, call_memop | |
289 | * will return 0, apparently nobody cares about this | |
290 | * case anyway. If num_users() returns more than 1, | |
291 | * we are not the only user of the plane's memory. | |
292 | */ | |
293 | if (call_memop(q, plane, num_users, | |
294 | vb->planes[plane].mem_priv) > 1) | |
295 | return true; | |
296 | } | |
297 | return false; | |
298 | } | |
299 | ||
300 | /** | |
301 | * __buffers_in_use() - return true if any buffers on the queue are in use and | |
302 | * the queue cannot be freed (by the means of REQBUFS(0)) call | |
303 | */ | |
304 | static bool __buffers_in_use(struct vb2_queue *q) | |
305 | { | |
306 | unsigned int buffer; | |
307 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
308 | if (__buffer_in_use(q, q->bufs[buffer])) | |
309 | return true; | |
310 | } | |
311 | return false; | |
312 | } | |
313 | ||
e23ccc0a PO |
314 | /** |
315 | * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be | |
316 | * returned to userspace | |
317 | */ | |
318 | static int __fill_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b) | |
319 | { | |
320 | struct vb2_queue *q = vb->vb2_queue; | |
321 | int ret = 0; | |
322 | ||
ea42c8ec | 323 | /* Copy back data such as timestamp, flags, input, etc. */ |
e23ccc0a PO |
324 | memcpy(b, &vb->v4l2_buf, offsetof(struct v4l2_buffer, m)); |
325 | b->input = vb->v4l2_buf.input; | |
326 | b->reserved = vb->v4l2_buf.reserved; | |
327 | ||
328 | if (V4L2_TYPE_IS_MULTIPLANAR(q->type)) { | |
329 | ret = __verify_planes_array(vb, b); | |
330 | if (ret) | |
331 | return ret; | |
332 | ||
333 | /* | |
334 | * Fill in plane-related data if userspace provided an array | |
335 | * for it. The memory and size is verified above. | |
336 | */ | |
337 | memcpy(b->m.planes, vb->v4l2_planes, | |
338 | b->length * sizeof(struct v4l2_plane)); | |
339 | } else { | |
340 | /* | |
341 | * We use length and offset in v4l2_planes array even for | |
342 | * single-planar buffers, but userspace does not. | |
343 | */ | |
344 | b->length = vb->v4l2_planes[0].length; | |
345 | b->bytesused = vb->v4l2_planes[0].bytesused; | |
346 | if (q->memory == V4L2_MEMORY_MMAP) | |
347 | b->m.offset = vb->v4l2_planes[0].m.mem_offset; | |
348 | else if (q->memory == V4L2_MEMORY_USERPTR) | |
349 | b->m.userptr = vb->v4l2_planes[0].m.userptr; | |
350 | } | |
351 | ||
ea42c8ec MS |
352 | /* |
353 | * Clear any buffer state related flags. | |
354 | */ | |
355 | b->flags &= ~V4L2_BUFFER_STATE_FLAGS; | |
e23ccc0a PO |
356 | |
357 | switch (vb->state) { | |
358 | case VB2_BUF_STATE_QUEUED: | |
359 | case VB2_BUF_STATE_ACTIVE: | |
360 | b->flags |= V4L2_BUF_FLAG_QUEUED; | |
361 | break; | |
362 | case VB2_BUF_STATE_ERROR: | |
363 | b->flags |= V4L2_BUF_FLAG_ERROR; | |
364 | /* fall through */ | |
365 | case VB2_BUF_STATE_DONE: | |
366 | b->flags |= V4L2_BUF_FLAG_DONE; | |
367 | break; | |
368 | case VB2_BUF_STATE_DEQUEUED: | |
ebc087d0 | 369 | case VB2_BUF_STATE_PREPARED: |
e23ccc0a PO |
370 | /* nothing */ |
371 | break; | |
372 | } | |
373 | ||
25a27d91 | 374 | if (__buffer_in_use(q, vb)) |
e23ccc0a PO |
375 | b->flags |= V4L2_BUF_FLAG_MAPPED; |
376 | ||
377 | return ret; | |
378 | } | |
379 | ||
380 | /** | |
381 | * vb2_querybuf() - query video buffer information | |
382 | * @q: videobuf queue | |
383 | * @b: buffer struct passed from userspace to vidioc_querybuf handler | |
384 | * in driver | |
385 | * | |
386 | * Should be called from vidioc_querybuf ioctl handler in driver. | |
387 | * This function will verify the passed v4l2_buffer structure and fill the | |
388 | * relevant information for the userspace. | |
389 | * | |
390 | * The return values from this function are intended to be directly returned | |
391 | * from vidioc_querybuf handler in driver. | |
392 | */ | |
393 | int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b) | |
394 | { | |
395 | struct vb2_buffer *vb; | |
396 | ||
397 | if (b->type != q->type) { | |
398 | dprintk(1, "querybuf: wrong buffer type\n"); | |
399 | return -EINVAL; | |
400 | } | |
401 | ||
402 | if (b->index >= q->num_buffers) { | |
403 | dprintk(1, "querybuf: buffer index out of range\n"); | |
404 | return -EINVAL; | |
405 | } | |
406 | vb = q->bufs[b->index]; | |
407 | ||
408 | return __fill_v4l2_buffer(vb, b); | |
409 | } | |
410 | EXPORT_SYMBOL(vb2_querybuf); | |
411 | ||
412 | /** | |
413 | * __verify_userptr_ops() - verify that all memory operations required for | |
414 | * USERPTR queue type have been provided | |
415 | */ | |
416 | static int __verify_userptr_ops(struct vb2_queue *q) | |
417 | { | |
418 | if (!(q->io_modes & VB2_USERPTR) || !q->mem_ops->get_userptr || | |
419 | !q->mem_ops->put_userptr) | |
420 | return -EINVAL; | |
421 | ||
422 | return 0; | |
423 | } | |
424 | ||
425 | /** | |
426 | * __verify_mmap_ops() - verify that all memory operations required for | |
427 | * MMAP queue type have been provided | |
428 | */ | |
429 | static int __verify_mmap_ops(struct vb2_queue *q) | |
430 | { | |
431 | if (!(q->io_modes & VB2_MMAP) || !q->mem_ops->alloc || | |
432 | !q->mem_ops->put || !q->mem_ops->mmap) | |
433 | return -EINVAL; | |
434 | ||
435 | return 0; | |
436 | } | |
437 | ||
e23ccc0a PO |
438 | /** |
439 | * vb2_reqbufs() - Initiate streaming | |
440 | * @q: videobuf2 queue | |
441 | * @req: struct passed from userspace to vidioc_reqbufs handler in driver | |
442 | * | |
443 | * Should be called from vidioc_reqbufs ioctl handler of a driver. | |
444 | * This function: | |
445 | * 1) verifies streaming parameters passed from the userspace, | |
446 | * 2) sets up the queue, | |
447 | * 3) negotiates number of buffers and planes per buffer with the driver | |
448 | * to be used during streaming, | |
449 | * 4) allocates internal buffer structures (struct vb2_buffer), according to | |
450 | * the agreed parameters, | |
451 | * 5) for MMAP memory type, allocates actual video memory, using the | |
452 | * memory handling/allocation routines provided during queue initialization | |
453 | * | |
454 | * If req->count is 0, all the memory will be freed instead. | |
455 | * If the queue has been allocated previously (by a previous vb2_reqbufs) call | |
456 | * and the queue is not busy, memory will be reallocated. | |
457 | * | |
458 | * The return values from this function are intended to be directly returned | |
459 | * from vidioc_reqbufs handler in driver. | |
460 | */ | |
461 | int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) | |
462 | { | |
463 | unsigned int num_buffers, num_planes; | |
e23ccc0a PO |
464 | int ret = 0; |
465 | ||
b25748fe MS |
466 | if (q->fileio) { |
467 | dprintk(1, "reqbufs: file io in progress\n"); | |
468 | return -EBUSY; | |
469 | } | |
470 | ||
e23ccc0a PO |
471 | if (req->memory != V4L2_MEMORY_MMAP |
472 | && req->memory != V4L2_MEMORY_USERPTR) { | |
473 | dprintk(1, "reqbufs: unsupported memory type\n"); | |
474 | return -EINVAL; | |
475 | } | |
476 | ||
477 | if (req->type != q->type) { | |
478 | dprintk(1, "reqbufs: requested type is incorrect\n"); | |
479 | return -EINVAL; | |
480 | } | |
481 | ||
482 | if (q->streaming) { | |
483 | dprintk(1, "reqbufs: streaming active\n"); | |
484 | return -EBUSY; | |
485 | } | |
486 | ||
487 | /* | |
488 | * Make sure all the required memory ops for given memory type | |
489 | * are available. | |
490 | */ | |
491 | if (req->memory == V4L2_MEMORY_MMAP && __verify_mmap_ops(q)) { | |
492 | dprintk(1, "reqbufs: MMAP for current setup unsupported\n"); | |
493 | return -EINVAL; | |
494 | } | |
495 | ||
496 | if (req->memory == V4L2_MEMORY_USERPTR && __verify_userptr_ops(q)) { | |
497 | dprintk(1, "reqbufs: USERPTR for current setup unsupported\n"); | |
498 | return -EINVAL; | |
499 | } | |
500 | ||
29e3fbd8 | 501 | if (req->count == 0 || q->num_buffers != 0 || q->memory != req->memory) { |
e23ccc0a PO |
502 | /* |
503 | * We already have buffers allocated, so first check if they | |
504 | * are not in use and can be freed. | |
505 | */ | |
506 | if (q->memory == V4L2_MEMORY_MMAP && __buffers_in_use(q)) { | |
507 | dprintk(1, "reqbufs: memory in use, cannot free\n"); | |
508 | return -EBUSY; | |
509 | } | |
510 | ||
72f1fc33 | 511 | __vb2_queue_free(q); |
29e3fbd8 MS |
512 | |
513 | /* | |
514 | * In case of REQBUFS(0) return immediately without calling | |
515 | * driver's queue_setup() callback and allocating resources. | |
516 | */ | |
517 | if (req->count == 0) | |
518 | return 0; | |
e23ccc0a PO |
519 | } |
520 | ||
521 | /* | |
522 | * Make sure the requested values and current defaults are sane. | |
523 | */ | |
524 | num_buffers = min_t(unsigned int, req->count, VIDEO_MAX_FRAME); | |
c1426bc7 | 525 | memset(q->plane_sizes, 0, sizeof(q->plane_sizes)); |
e23ccc0a | 526 | memset(q->alloc_ctx, 0, sizeof(q->alloc_ctx)); |
13b14095 | 527 | q->memory = req->memory; |
e23ccc0a PO |
528 | |
529 | /* | |
530 | * Ask the driver how many buffers and planes per buffer it requires. | |
531 | * Driver also sets the size and allocator context for each plane. | |
532 | */ | |
533 | ret = call_qop(q, queue_setup, q, &num_buffers, &num_planes, | |
c1426bc7 | 534 | q->plane_sizes, q->alloc_ctx); |
e23ccc0a PO |
535 | if (ret) |
536 | return ret; | |
537 | ||
538 | /* Finally, allocate buffers and video memory */ | |
c1426bc7 | 539 | ret = __vb2_queue_alloc(q, req->memory, num_buffers, num_planes); |
66072d4f MS |
540 | if (ret == 0) { |
541 | dprintk(1, "Memory allocation failed\n"); | |
542 | return -ENOMEM; | |
e23ccc0a PO |
543 | } |
544 | ||
545 | /* | |
546 | * Check if driver can handle the allocated number of buffers. | |
547 | */ | |
548 | if (ret < num_buffers) { | |
549 | unsigned int orig_num_buffers; | |
550 | ||
551 | orig_num_buffers = num_buffers = ret; | |
552 | ret = call_qop(q, queue_setup, q, &num_buffers, &num_planes, | |
c1426bc7 | 553 | q->plane_sizes, q->alloc_ctx); |
e23ccc0a PO |
554 | if (ret) |
555 | goto free_mem; | |
556 | ||
557 | if (orig_num_buffers < num_buffers) { | |
558 | ret = -ENOMEM; | |
559 | goto free_mem; | |
560 | } | |
561 | ||
562 | /* | |
563 | * Ok, driver accepted smaller number of buffers. | |
564 | */ | |
565 | ret = num_buffers; | |
566 | } | |
567 | ||
e23ccc0a PO |
568 | /* |
569 | * Return the number of successfully allocated buffers | |
570 | * to the userspace. | |
571 | */ | |
572 | req->count = ret; | |
573 | ||
574 | return 0; | |
575 | ||
576 | free_mem: | |
577 | __vb2_queue_free(q); | |
578 | return ret; | |
579 | } | |
580 | EXPORT_SYMBOL_GPL(vb2_reqbufs); | |
581 | ||
582 | /** | |
583 | * vb2_plane_vaddr() - Return a kernel virtual address of a given plane | |
584 | * @vb: vb2_buffer to which the plane in question belongs to | |
585 | * @plane_no: plane number for which the address is to be returned | |
586 | * | |
587 | * This function returns a kernel virtual address of a given plane if | |
588 | * such a mapping exist, NULL otherwise. | |
589 | */ | |
590 | void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no) | |
591 | { | |
592 | struct vb2_queue *q = vb->vb2_queue; | |
593 | ||
594 | if (plane_no > vb->num_planes) | |
595 | return NULL; | |
596 | ||
597 | return call_memop(q, plane_no, vaddr, vb->planes[plane_no].mem_priv); | |
598 | ||
599 | } | |
600 | EXPORT_SYMBOL_GPL(vb2_plane_vaddr); | |
601 | ||
602 | /** | |
603 | * vb2_plane_cookie() - Return allocator specific cookie for the given plane | |
604 | * @vb: vb2_buffer to which the plane in question belongs to | |
605 | * @plane_no: plane number for which the cookie is to be returned | |
606 | * | |
607 | * This function returns an allocator specific cookie for a given plane if | |
608 | * available, NULL otherwise. The allocator should provide some simple static | |
609 | * inline function, which would convert this cookie to the allocator specific | |
610 | * type that can be used directly by the driver to access the buffer. This can | |
611 | * be for example physical address, pointer to scatter list or IOMMU mapping. | |
612 | */ | |
613 | void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no) | |
614 | { | |
615 | struct vb2_queue *q = vb->vb2_queue; | |
616 | ||
617 | if (plane_no > vb->num_planes) | |
618 | return NULL; | |
619 | ||
620 | return call_memop(q, plane_no, cookie, vb->planes[plane_no].mem_priv); | |
621 | } | |
622 | EXPORT_SYMBOL_GPL(vb2_plane_cookie); | |
623 | ||
624 | /** | |
625 | * vb2_buffer_done() - inform videobuf that an operation on a buffer is finished | |
626 | * @vb: vb2_buffer returned from the driver | |
627 | * @state: either VB2_BUF_STATE_DONE if the operation finished successfully | |
628 | * or VB2_BUF_STATE_ERROR if the operation finished with an error | |
629 | * | |
630 | * This function should be called by the driver after a hardware operation on | |
631 | * a buffer is finished and the buffer may be returned to userspace. The driver | |
632 | * cannot use this buffer anymore until it is queued back to it by videobuf | |
633 | * by the means of buf_queue callback. Only buffers previously queued to the | |
634 | * driver by buf_queue can be passed to this function. | |
635 | */ | |
636 | void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state) | |
637 | { | |
638 | struct vb2_queue *q = vb->vb2_queue; | |
639 | unsigned long flags; | |
640 | ||
641 | if (vb->state != VB2_BUF_STATE_ACTIVE) | |
642 | return; | |
643 | ||
644 | if (state != VB2_BUF_STATE_DONE && state != VB2_BUF_STATE_ERROR) | |
645 | return; | |
646 | ||
647 | dprintk(4, "Done processing on buffer %d, state: %d\n", | |
648 | vb->v4l2_buf.index, vb->state); | |
649 | ||
650 | /* Add the buffer to the done buffers list */ | |
651 | spin_lock_irqsave(&q->done_lock, flags); | |
652 | vb->state = state; | |
653 | list_add_tail(&vb->done_entry, &q->done_list); | |
654 | atomic_dec(&q->queued_count); | |
655 | spin_unlock_irqrestore(&q->done_lock, flags); | |
656 | ||
657 | /* Inform any processes that may be waiting for buffers */ | |
658 | wake_up(&q->done_wq); | |
659 | } | |
660 | EXPORT_SYMBOL_GPL(vb2_buffer_done); | |
661 | ||
662 | /** | |
663 | * __fill_vb2_buffer() - fill a vb2_buffer with information provided in | |
664 | * a v4l2_buffer by the userspace | |
665 | */ | |
666 | static int __fill_vb2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b, | |
667 | struct v4l2_plane *v4l2_planes) | |
668 | { | |
669 | unsigned int plane; | |
670 | int ret; | |
671 | ||
672 | if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) { | |
673 | /* | |
674 | * Verify that the userspace gave us a valid array for | |
675 | * plane information. | |
676 | */ | |
677 | ret = __verify_planes_array(vb, b); | |
678 | if (ret) | |
679 | return ret; | |
680 | ||
681 | /* Fill in driver-provided information for OUTPUT types */ | |
682 | if (V4L2_TYPE_IS_OUTPUT(b->type)) { | |
683 | /* | |
684 | * Will have to go up to b->length when API starts | |
685 | * accepting variable number of planes. | |
686 | */ | |
687 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
688 | v4l2_planes[plane].bytesused = | |
689 | b->m.planes[plane].bytesused; | |
690 | v4l2_planes[plane].data_offset = | |
691 | b->m.planes[plane].data_offset; | |
692 | } | |
693 | } | |
694 | ||
695 | if (b->memory == V4L2_MEMORY_USERPTR) { | |
696 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
697 | v4l2_planes[plane].m.userptr = | |
698 | b->m.planes[plane].m.userptr; | |
699 | v4l2_planes[plane].length = | |
700 | b->m.planes[plane].length; | |
701 | } | |
702 | } | |
703 | } else { | |
704 | /* | |
705 | * Single-planar buffers do not use planes array, | |
706 | * so fill in relevant v4l2_buffer struct fields instead. | |
707 | * In videobuf we use our internal V4l2_planes struct for | |
708 | * single-planar buffers as well, for simplicity. | |
709 | */ | |
710 | if (V4L2_TYPE_IS_OUTPUT(b->type)) | |
711 | v4l2_planes[0].bytesused = b->bytesused; | |
712 | ||
713 | if (b->memory == V4L2_MEMORY_USERPTR) { | |
714 | v4l2_planes[0].m.userptr = b->m.userptr; | |
715 | v4l2_planes[0].length = b->length; | |
716 | } | |
717 | } | |
718 | ||
719 | vb->v4l2_buf.field = b->field; | |
720 | vb->v4l2_buf.timestamp = b->timestamp; | |
ea42c8ec MS |
721 | vb->v4l2_buf.input = b->input; |
722 | vb->v4l2_buf.flags = b->flags & ~V4L2_BUFFER_STATE_FLAGS; | |
e23ccc0a PO |
723 | |
724 | return 0; | |
725 | } | |
726 | ||
727 | /** | |
728 | * __qbuf_userptr() - handle qbuf of a USERPTR buffer | |
729 | */ | |
730 | static int __qbuf_userptr(struct vb2_buffer *vb, struct v4l2_buffer *b) | |
731 | { | |
732 | struct v4l2_plane planes[VIDEO_MAX_PLANES]; | |
733 | struct vb2_queue *q = vb->vb2_queue; | |
734 | void *mem_priv; | |
735 | unsigned int plane; | |
736 | int ret; | |
737 | int write = !V4L2_TYPE_IS_OUTPUT(q->type); | |
738 | ||
739 | /* Verify and copy relevant information provided by the userspace */ | |
740 | ret = __fill_vb2_buffer(vb, b, planes); | |
741 | if (ret) | |
742 | return ret; | |
743 | ||
744 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
745 | /* Skip the plane if already verified */ | |
746 | if (vb->v4l2_planes[plane].m.userptr == planes[plane].m.userptr | |
747 | && vb->v4l2_planes[plane].length == planes[plane].length) | |
748 | continue; | |
749 | ||
750 | dprintk(3, "qbuf: userspace address for plane %d changed, " | |
751 | "reacquiring memory\n", plane); | |
752 | ||
c1426bc7 MS |
753 | /* Check if the provided plane buffer is large enough */ |
754 | if (planes[plane].length < q->plane_sizes[plane]) { | |
4c2625db | 755 | ret = -EINVAL; |
c1426bc7 MS |
756 | goto err; |
757 | } | |
758 | ||
e23ccc0a PO |
759 | /* Release previously acquired memory if present */ |
760 | if (vb->planes[plane].mem_priv) | |
761 | call_memop(q, plane, put_userptr, | |
762 | vb->planes[plane].mem_priv); | |
763 | ||
764 | vb->planes[plane].mem_priv = NULL; | |
c1426bc7 MS |
765 | vb->v4l2_planes[plane].m.userptr = 0; |
766 | vb->v4l2_planes[plane].length = 0; | |
e23ccc0a PO |
767 | |
768 | /* Acquire each plane's memory */ | |
769 | if (q->mem_ops->get_userptr) { | |
770 | mem_priv = q->mem_ops->get_userptr(q->alloc_ctx[plane], | |
771 | planes[plane].m.userptr, | |
772 | planes[plane].length, | |
773 | write); | |
774 | if (IS_ERR(mem_priv)) { | |
775 | dprintk(1, "qbuf: failed acquiring userspace " | |
776 | "memory for plane %d\n", plane); | |
777 | ret = PTR_ERR(mem_priv); | |
778 | goto err; | |
779 | } | |
780 | vb->planes[plane].mem_priv = mem_priv; | |
781 | } | |
782 | } | |
783 | ||
784 | /* | |
785 | * Call driver-specific initialization on the newly acquired buffer, | |
786 | * if provided. | |
787 | */ | |
788 | ret = call_qop(q, buf_init, vb); | |
789 | if (ret) { | |
790 | dprintk(1, "qbuf: buffer initialization failed\n"); | |
791 | goto err; | |
792 | } | |
793 | ||
794 | /* | |
795 | * Now that everything is in order, copy relevant information | |
796 | * provided by userspace. | |
797 | */ | |
798 | for (plane = 0; plane < vb->num_planes; ++plane) | |
799 | vb->v4l2_planes[plane] = planes[plane]; | |
800 | ||
801 | return 0; | |
802 | err: | |
803 | /* In case of errors, release planes that were already acquired */ | |
c1426bc7 MS |
804 | for (plane = 0; plane < vb->num_planes; ++plane) { |
805 | if (vb->planes[plane].mem_priv) | |
806 | call_memop(q, plane, put_userptr, | |
807 | vb->planes[plane].mem_priv); | |
808 | vb->planes[plane].mem_priv = NULL; | |
809 | vb->v4l2_planes[plane].m.userptr = 0; | |
810 | vb->v4l2_planes[plane].length = 0; | |
e23ccc0a PO |
811 | } |
812 | ||
813 | return ret; | |
814 | } | |
815 | ||
816 | /** | |
817 | * __qbuf_mmap() - handle qbuf of an MMAP buffer | |
818 | */ | |
819 | static int __qbuf_mmap(struct vb2_buffer *vb, struct v4l2_buffer *b) | |
820 | { | |
821 | return __fill_vb2_buffer(vb, b, vb->v4l2_planes); | |
822 | } | |
823 | ||
824 | /** | |
825 | * __enqueue_in_driver() - enqueue a vb2_buffer in driver for processing | |
826 | */ | |
827 | static void __enqueue_in_driver(struct vb2_buffer *vb) | |
828 | { | |
829 | struct vb2_queue *q = vb->vb2_queue; | |
830 | ||
831 | vb->state = VB2_BUF_STATE_ACTIVE; | |
832 | atomic_inc(&q->queued_count); | |
833 | q->ops->buf_queue(vb); | |
834 | } | |
835 | ||
ebc087d0 GL |
836 | static int __buf_prepare(struct vb2_buffer *vb, struct v4l2_buffer *b) |
837 | { | |
838 | struct vb2_queue *q = vb->vb2_queue; | |
839 | int ret; | |
840 | ||
841 | switch (q->memory) { | |
842 | case V4L2_MEMORY_MMAP: | |
843 | ret = __qbuf_mmap(vb, b); | |
844 | break; | |
845 | case V4L2_MEMORY_USERPTR: | |
846 | ret = __qbuf_userptr(vb, b); | |
847 | break; | |
848 | default: | |
849 | WARN(1, "Invalid queue type\n"); | |
850 | ret = -EINVAL; | |
851 | } | |
852 | ||
853 | if (!ret) | |
854 | ret = call_qop(q, buf_prepare, vb); | |
855 | if (ret) | |
856 | dprintk(1, "qbuf: buffer preparation failed: %d\n", ret); | |
857 | else | |
858 | vb->state = VB2_BUF_STATE_PREPARED; | |
859 | ||
860 | return ret; | |
861 | } | |
862 | ||
e23ccc0a PO |
863 | /** |
864 | * vb2_qbuf() - Queue a buffer from userspace | |
865 | * @q: videobuf2 queue | |
866 | * @b: buffer structure passed from userspace to vidioc_qbuf handler | |
867 | * in driver | |
868 | * | |
869 | * Should be called from vidioc_qbuf ioctl handler of a driver. | |
870 | * This function: | |
871 | * 1) verifies the passed buffer, | |
ebc087d0 GL |
872 | * 2) if necessary, calls buf_prepare callback in the driver (if provided), in |
873 | * which driver-specific buffer initialization can be performed, | |
e23ccc0a PO |
874 | * 3) if streaming is on, queues the buffer in driver by the means of buf_queue |
875 | * callback for processing. | |
876 | * | |
877 | * The return values from this function are intended to be directly returned | |
878 | * from vidioc_qbuf handler in driver. | |
879 | */ | |
880 | int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b) | |
881 | { | |
882 | struct vb2_buffer *vb; | |
ebc087d0 | 883 | int ret; |
e23ccc0a | 884 | |
b25748fe MS |
885 | if (q->fileio) { |
886 | dprintk(1, "qbuf: file io in progress\n"); | |
887 | return -EBUSY; | |
888 | } | |
889 | ||
e23ccc0a PO |
890 | if (b->type != q->type) { |
891 | dprintk(1, "qbuf: invalid buffer type\n"); | |
892 | return -EINVAL; | |
893 | } | |
894 | ||
895 | if (b->index >= q->num_buffers) { | |
896 | dprintk(1, "qbuf: buffer index out of range\n"); | |
897 | return -EINVAL; | |
898 | } | |
899 | ||
900 | vb = q->bufs[b->index]; | |
901 | if (NULL == vb) { | |
902 | /* Should never happen */ | |
903 | dprintk(1, "qbuf: buffer is NULL\n"); | |
904 | return -EINVAL; | |
905 | } | |
906 | ||
907 | if (b->memory != q->memory) { | |
908 | dprintk(1, "qbuf: invalid memory type\n"); | |
909 | return -EINVAL; | |
910 | } | |
911 | ||
ebc087d0 GL |
912 | switch (vb->state) { |
913 | case VB2_BUF_STATE_DEQUEUED: | |
914 | ret = __buf_prepare(vb, b); | |
915 | if (ret) | |
916 | return ret; | |
917 | case VB2_BUF_STATE_PREPARED: | |
918 | break; | |
919 | default: | |
e23ccc0a PO |
920 | dprintk(1, "qbuf: buffer already in use\n"); |
921 | return -EINVAL; | |
922 | } | |
923 | ||
e23ccc0a PO |
924 | /* |
925 | * Add to the queued buffers list, a buffer will stay on it until | |
926 | * dequeued in dqbuf. | |
927 | */ | |
928 | list_add_tail(&vb->queued_entry, &q->queued_list); | |
929 | vb->state = VB2_BUF_STATE_QUEUED; | |
930 | ||
931 | /* | |
932 | * If already streaming, give the buffer to driver for processing. | |
933 | * If not, the buffer will be given to driver on next streamon. | |
934 | */ | |
935 | if (q->streaming) | |
936 | __enqueue_in_driver(vb); | |
937 | ||
21db3e07 GL |
938 | /* Fill buffer information for the userspace */ |
939 | __fill_v4l2_buffer(vb, b); | |
940 | ||
e23ccc0a PO |
941 | dprintk(1, "qbuf of buffer %d succeeded\n", vb->v4l2_buf.index); |
942 | return 0; | |
943 | } | |
944 | EXPORT_SYMBOL_GPL(vb2_qbuf); | |
945 | ||
946 | /** | |
947 | * __vb2_wait_for_done_vb() - wait for a buffer to become available | |
948 | * for dequeuing | |
949 | * | |
950 | * Will sleep if required for nonblocking == false. | |
951 | */ | |
952 | static int __vb2_wait_for_done_vb(struct vb2_queue *q, int nonblocking) | |
953 | { | |
954 | /* | |
955 | * All operations on vb_done_list are performed under done_lock | |
956 | * spinlock protection. However, buffers may be removed from | |
957 | * it and returned to userspace only while holding both driver's | |
958 | * lock and the done_lock spinlock. Thus we can be sure that as | |
959 | * long as we hold the driver's lock, the list will remain not | |
960 | * empty if list_empty() check succeeds. | |
961 | */ | |
962 | ||
963 | for (;;) { | |
964 | int ret; | |
965 | ||
966 | if (!q->streaming) { | |
967 | dprintk(1, "Streaming off, will not wait for buffers\n"); | |
968 | return -EINVAL; | |
969 | } | |
970 | ||
971 | if (!list_empty(&q->done_list)) { | |
972 | /* | |
973 | * Found a buffer that we were waiting for. | |
974 | */ | |
975 | break; | |
976 | } | |
977 | ||
978 | if (nonblocking) { | |
979 | dprintk(1, "Nonblocking and no buffers to dequeue, " | |
980 | "will not wait\n"); | |
981 | return -EAGAIN; | |
982 | } | |
983 | ||
984 | /* | |
985 | * We are streaming and blocking, wait for another buffer to | |
986 | * become ready or for streamoff. Driver's lock is released to | |
987 | * allow streamoff or qbuf to be called while waiting. | |
988 | */ | |
989 | call_qop(q, wait_prepare, q); | |
990 | ||
991 | /* | |
992 | * All locks have been released, it is safe to sleep now. | |
993 | */ | |
994 | dprintk(3, "Will sleep waiting for buffers\n"); | |
995 | ret = wait_event_interruptible(q->done_wq, | |
996 | !list_empty(&q->done_list) || !q->streaming); | |
997 | ||
998 | /* | |
999 | * We need to reevaluate both conditions again after reacquiring | |
1000 | * the locks or return an error if one occurred. | |
1001 | */ | |
1002 | call_qop(q, wait_finish, q); | |
1003 | if (ret) | |
1004 | return ret; | |
1005 | } | |
1006 | return 0; | |
1007 | } | |
1008 | ||
1009 | /** | |
1010 | * __vb2_get_done_vb() - get a buffer ready for dequeuing | |
1011 | * | |
1012 | * Will sleep if required for nonblocking == false. | |
1013 | */ | |
1014 | static int __vb2_get_done_vb(struct vb2_queue *q, struct vb2_buffer **vb, | |
1015 | int nonblocking) | |
1016 | { | |
1017 | unsigned long flags; | |
1018 | int ret; | |
1019 | ||
1020 | /* | |
1021 | * Wait for at least one buffer to become available on the done_list. | |
1022 | */ | |
1023 | ret = __vb2_wait_for_done_vb(q, nonblocking); | |
1024 | if (ret) | |
1025 | return ret; | |
1026 | ||
1027 | /* | |
1028 | * Driver's lock has been held since we last verified that done_list | |
1029 | * is not empty, so no need for another list_empty(done_list) check. | |
1030 | */ | |
1031 | spin_lock_irqsave(&q->done_lock, flags); | |
1032 | *vb = list_first_entry(&q->done_list, struct vb2_buffer, done_entry); | |
1033 | list_del(&(*vb)->done_entry); | |
1034 | spin_unlock_irqrestore(&q->done_lock, flags); | |
1035 | ||
1036 | return 0; | |
1037 | } | |
1038 | ||
1039 | /** | |
1040 | * vb2_wait_for_all_buffers() - wait until all buffers are given back to vb2 | |
1041 | * @q: videobuf2 queue | |
1042 | * | |
1043 | * This function will wait until all buffers that have been given to the driver | |
1044 | * by buf_queue() are given back to vb2 with vb2_buffer_done(). It doesn't call | |
1045 | * wait_prepare, wait_finish pair. It is intended to be called with all locks | |
1046 | * taken, for example from stop_streaming() callback. | |
1047 | */ | |
1048 | int vb2_wait_for_all_buffers(struct vb2_queue *q) | |
1049 | { | |
1050 | if (!q->streaming) { | |
1051 | dprintk(1, "Streaming off, will not wait for buffers\n"); | |
1052 | return -EINVAL; | |
1053 | } | |
1054 | ||
1055 | wait_event(q->done_wq, !atomic_read(&q->queued_count)); | |
1056 | return 0; | |
1057 | } | |
1058 | EXPORT_SYMBOL_GPL(vb2_wait_for_all_buffers); | |
1059 | ||
1060 | /** | |
1061 | * vb2_dqbuf() - Dequeue a buffer to the userspace | |
1062 | * @q: videobuf2 queue | |
1063 | * @b: buffer structure passed from userspace to vidioc_dqbuf handler | |
1064 | * in driver | |
1065 | * @nonblocking: if true, this call will not sleep waiting for a buffer if no | |
1066 | * buffers ready for dequeuing are present. Normally the driver | |
1067 | * would be passing (file->f_flags & O_NONBLOCK) here | |
1068 | * | |
1069 | * Should be called from vidioc_dqbuf ioctl handler of a driver. | |
1070 | * This function: | |
1071 | * 1) verifies the passed buffer, | |
1072 | * 2) calls buf_finish callback in the driver (if provided), in which | |
1073 | * driver can perform any additional operations that may be required before | |
1074 | * returning the buffer to userspace, such as cache sync, | |
1075 | * 3) the buffer struct members are filled with relevant information for | |
1076 | * the userspace. | |
1077 | * | |
1078 | * The return values from this function are intended to be directly returned | |
1079 | * from vidioc_dqbuf handler in driver. | |
1080 | */ | |
1081 | int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking) | |
1082 | { | |
1083 | struct vb2_buffer *vb = NULL; | |
1084 | int ret; | |
1085 | ||
b25748fe MS |
1086 | if (q->fileio) { |
1087 | dprintk(1, "dqbuf: file io in progress\n"); | |
1088 | return -EBUSY; | |
1089 | } | |
1090 | ||
e23ccc0a PO |
1091 | if (b->type != q->type) { |
1092 | dprintk(1, "dqbuf: invalid buffer type\n"); | |
1093 | return -EINVAL; | |
1094 | } | |
1095 | ||
1096 | ret = __vb2_get_done_vb(q, &vb, nonblocking); | |
1097 | if (ret < 0) { | |
1098 | dprintk(1, "dqbuf: error getting next done buffer\n"); | |
1099 | return ret; | |
1100 | } | |
1101 | ||
1102 | ret = call_qop(q, buf_finish, vb); | |
1103 | if (ret) { | |
1104 | dprintk(1, "dqbuf: buffer finish failed\n"); | |
1105 | return ret; | |
1106 | } | |
1107 | ||
1108 | switch (vb->state) { | |
1109 | case VB2_BUF_STATE_DONE: | |
1110 | dprintk(3, "dqbuf: Returning done buffer\n"); | |
1111 | break; | |
1112 | case VB2_BUF_STATE_ERROR: | |
1113 | dprintk(3, "dqbuf: Returning done buffer with errors\n"); | |
1114 | break; | |
1115 | default: | |
1116 | dprintk(1, "dqbuf: Invalid buffer state\n"); | |
1117 | return -EINVAL; | |
1118 | } | |
1119 | ||
1120 | /* Fill buffer information for the userspace */ | |
1121 | __fill_v4l2_buffer(vb, b); | |
1122 | /* Remove from videobuf queue */ | |
1123 | list_del(&vb->queued_entry); | |
1124 | ||
1125 | dprintk(1, "dqbuf of buffer %d, with state %d\n", | |
1126 | vb->v4l2_buf.index, vb->state); | |
1127 | ||
1128 | vb->state = VB2_BUF_STATE_DEQUEUED; | |
1129 | return 0; | |
1130 | } | |
1131 | EXPORT_SYMBOL_GPL(vb2_dqbuf); | |
1132 | ||
bd323e28 MS |
1133 | /** |
1134 | * __vb2_queue_cancel() - cancel and stop (pause) streaming | |
1135 | * | |
1136 | * Removes all queued buffers from driver's queue and all buffers queued by | |
1137 | * userspace from videobuf's queue. Returns to state after reqbufs. | |
1138 | */ | |
1139 | static void __vb2_queue_cancel(struct vb2_queue *q) | |
1140 | { | |
1141 | unsigned int i; | |
1142 | ||
1143 | /* | |
1144 | * Tell driver to stop all transactions and release all queued | |
1145 | * buffers. | |
1146 | */ | |
1147 | if (q->streaming) | |
1148 | call_qop(q, stop_streaming, q); | |
1149 | q->streaming = 0; | |
1150 | ||
1151 | /* | |
1152 | * Remove all buffers from videobuf's list... | |
1153 | */ | |
1154 | INIT_LIST_HEAD(&q->queued_list); | |
1155 | /* | |
1156 | * ...and done list; userspace will not receive any buffers it | |
1157 | * has not already dequeued before initiating cancel. | |
1158 | */ | |
1159 | INIT_LIST_HEAD(&q->done_list); | |
1160 | atomic_set(&q->queued_count, 0); | |
1161 | wake_up_all(&q->done_wq); | |
1162 | ||
1163 | /* | |
1164 | * Reinitialize all buffers for next use. | |
1165 | */ | |
1166 | for (i = 0; i < q->num_buffers; ++i) | |
1167 | q->bufs[i]->state = VB2_BUF_STATE_DEQUEUED; | |
1168 | } | |
1169 | ||
e23ccc0a PO |
1170 | /** |
1171 | * vb2_streamon - start streaming | |
1172 | * @q: videobuf2 queue | |
1173 | * @type: type argument passed from userspace to vidioc_streamon handler | |
1174 | * | |
1175 | * Should be called from vidioc_streamon handler of a driver. | |
1176 | * This function: | |
1177 | * 1) verifies current state | |
bd323e28 | 1178 | * 2) passes any previously queued buffers to the driver and starts streaming |
e23ccc0a PO |
1179 | * |
1180 | * The return values from this function are intended to be directly returned | |
1181 | * from vidioc_streamon handler in the driver. | |
1182 | */ | |
1183 | int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type) | |
1184 | { | |
1185 | struct vb2_buffer *vb; | |
5db2c3ba | 1186 | int ret; |
e23ccc0a | 1187 | |
b25748fe MS |
1188 | if (q->fileio) { |
1189 | dprintk(1, "streamon: file io in progress\n"); | |
1190 | return -EBUSY; | |
1191 | } | |
1192 | ||
e23ccc0a PO |
1193 | if (type != q->type) { |
1194 | dprintk(1, "streamon: invalid stream type\n"); | |
1195 | return -EINVAL; | |
1196 | } | |
1197 | ||
1198 | if (q->streaming) { | |
1199 | dprintk(1, "streamon: already streaming\n"); | |
1200 | return -EBUSY; | |
1201 | } | |
1202 | ||
1203 | /* | |
bd323e28 MS |
1204 | * If any buffers were queued before streamon, |
1205 | * we can now pass them to driver for processing. | |
e23ccc0a | 1206 | */ |
bd323e28 MS |
1207 | list_for_each_entry(vb, &q->queued_list, queued_entry) |
1208 | __enqueue_in_driver(vb); | |
e23ccc0a | 1209 | |
e23ccc0a PO |
1210 | /* |
1211 | * Let driver notice that streaming state has been enabled. | |
1212 | */ | |
bd323e28 | 1213 | ret = call_qop(q, start_streaming, q, atomic_read(&q->queued_count)); |
5db2c3ba PO |
1214 | if (ret) { |
1215 | dprintk(1, "streamon: driver refused to start streaming\n"); | |
bd323e28 | 1216 | __vb2_queue_cancel(q); |
5db2c3ba PO |
1217 | return ret; |
1218 | } | |
1219 | ||
1220 | q->streaming = 1; | |
e23ccc0a | 1221 | |
e23ccc0a PO |
1222 | dprintk(3, "Streamon successful\n"); |
1223 | return 0; | |
1224 | } | |
1225 | EXPORT_SYMBOL_GPL(vb2_streamon); | |
1226 | ||
e23ccc0a PO |
1227 | |
1228 | /** | |
1229 | * vb2_streamoff - stop streaming | |
1230 | * @q: videobuf2 queue | |
1231 | * @type: type argument passed from userspace to vidioc_streamoff handler | |
1232 | * | |
1233 | * Should be called from vidioc_streamoff handler of a driver. | |
1234 | * This function: | |
1235 | * 1) verifies current state, | |
1236 | * 2) stop streaming and dequeues any queued buffers, including those previously | |
1237 | * passed to the driver (after waiting for the driver to finish). | |
1238 | * | |
1239 | * This call can be used for pausing playback. | |
1240 | * The return values from this function are intended to be directly returned | |
1241 | * from vidioc_streamoff handler in the driver | |
1242 | */ | |
1243 | int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type) | |
1244 | { | |
b25748fe MS |
1245 | if (q->fileio) { |
1246 | dprintk(1, "streamoff: file io in progress\n"); | |
1247 | return -EBUSY; | |
1248 | } | |
1249 | ||
e23ccc0a PO |
1250 | if (type != q->type) { |
1251 | dprintk(1, "streamoff: invalid stream type\n"); | |
1252 | return -EINVAL; | |
1253 | } | |
1254 | ||
1255 | if (!q->streaming) { | |
1256 | dprintk(1, "streamoff: not streaming\n"); | |
1257 | return -EINVAL; | |
1258 | } | |
1259 | ||
1260 | /* | |
1261 | * Cancel will pause streaming and remove all buffers from the driver | |
1262 | * and videobuf, effectively returning control over them to userspace. | |
1263 | */ | |
1264 | __vb2_queue_cancel(q); | |
1265 | ||
1266 | dprintk(3, "Streamoff successful\n"); | |
1267 | return 0; | |
1268 | } | |
1269 | EXPORT_SYMBOL_GPL(vb2_streamoff); | |
1270 | ||
1271 | /** | |
1272 | * __find_plane_by_offset() - find plane associated with the given offset off | |
1273 | */ | |
1274 | static int __find_plane_by_offset(struct vb2_queue *q, unsigned long off, | |
1275 | unsigned int *_buffer, unsigned int *_plane) | |
1276 | { | |
1277 | struct vb2_buffer *vb; | |
1278 | unsigned int buffer, plane; | |
1279 | ||
1280 | /* | |
1281 | * Go over all buffers and their planes, comparing the given offset | |
1282 | * with an offset assigned to each plane. If a match is found, | |
1283 | * return its buffer and plane numbers. | |
1284 | */ | |
1285 | for (buffer = 0; buffer < q->num_buffers; ++buffer) { | |
1286 | vb = q->bufs[buffer]; | |
1287 | ||
1288 | for (plane = 0; plane < vb->num_planes; ++plane) { | |
1289 | if (vb->v4l2_planes[plane].m.mem_offset == off) { | |
1290 | *_buffer = buffer; | |
1291 | *_plane = plane; | |
1292 | return 0; | |
1293 | } | |
1294 | } | |
1295 | } | |
1296 | ||
1297 | return -EINVAL; | |
1298 | } | |
1299 | ||
1300 | /** | |
1301 | * vb2_mmap() - map video buffers into application address space | |
1302 | * @q: videobuf2 queue | |
1303 | * @vma: vma passed to the mmap file operation handler in the driver | |
1304 | * | |
1305 | * Should be called from mmap file operation handler of a driver. | |
1306 | * This function maps one plane of one of the available video buffers to | |
1307 | * userspace. To map whole video memory allocated on reqbufs, this function | |
1308 | * has to be called once per each plane per each buffer previously allocated. | |
1309 | * | |
1310 | * When the userspace application calls mmap, it passes to it an offset returned | |
1311 | * to it earlier by the means of vidioc_querybuf handler. That offset acts as | |
1312 | * a "cookie", which is then used to identify the plane to be mapped. | |
1313 | * This function finds a plane with a matching offset and a mapping is performed | |
1314 | * by the means of a provided memory operation. | |
1315 | * | |
1316 | * The return values from this function are intended to be directly returned | |
1317 | * from the mmap handler in driver. | |
1318 | */ | |
1319 | int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma) | |
1320 | { | |
1321 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
1322 | struct vb2_plane *vb_plane; | |
1323 | struct vb2_buffer *vb; | |
1324 | unsigned int buffer, plane; | |
1325 | int ret; | |
1326 | ||
1327 | if (q->memory != V4L2_MEMORY_MMAP) { | |
1328 | dprintk(1, "Queue is not currently set up for mmap\n"); | |
1329 | return -EINVAL; | |
1330 | } | |
1331 | ||
1332 | /* | |
1333 | * Check memory area access mode. | |
1334 | */ | |
1335 | if (!(vma->vm_flags & VM_SHARED)) { | |
1336 | dprintk(1, "Invalid vma flags, VM_SHARED needed\n"); | |
1337 | return -EINVAL; | |
1338 | } | |
1339 | if (V4L2_TYPE_IS_OUTPUT(q->type)) { | |
1340 | if (!(vma->vm_flags & VM_WRITE)) { | |
1341 | dprintk(1, "Invalid vma flags, VM_WRITE needed\n"); | |
1342 | return -EINVAL; | |
1343 | } | |
1344 | } else { | |
1345 | if (!(vma->vm_flags & VM_READ)) { | |
1346 | dprintk(1, "Invalid vma flags, VM_READ needed\n"); | |
1347 | return -EINVAL; | |
1348 | } | |
1349 | } | |
1350 | ||
1351 | /* | |
1352 | * Find the plane corresponding to the offset passed by userspace. | |
1353 | */ | |
1354 | ret = __find_plane_by_offset(q, off, &buffer, &plane); | |
1355 | if (ret) | |
1356 | return ret; | |
1357 | ||
1358 | vb = q->bufs[buffer]; | |
1359 | vb_plane = &vb->planes[plane]; | |
1360 | ||
1361 | ret = q->mem_ops->mmap(vb_plane->mem_priv, vma); | |
1362 | if (ret) | |
1363 | return ret; | |
1364 | ||
e23ccc0a PO |
1365 | dprintk(3, "Buffer %d, plane %d successfully mapped\n", buffer, plane); |
1366 | return 0; | |
1367 | } | |
1368 | EXPORT_SYMBOL_GPL(vb2_mmap); | |
1369 | ||
b25748fe MS |
1370 | static int __vb2_init_fileio(struct vb2_queue *q, int read); |
1371 | static int __vb2_cleanup_fileio(struct vb2_queue *q); | |
e23ccc0a PO |
1372 | |
1373 | /** | |
1374 | * vb2_poll() - implements poll userspace operation | |
1375 | * @q: videobuf2 queue | |
1376 | * @file: file argument passed to the poll file operation handler | |
1377 | * @wait: wait argument passed to the poll file operation handler | |
1378 | * | |
1379 | * This function implements poll file operation handler for a driver. | |
1380 | * For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will | |
1381 | * be informed that the file descriptor of a video device is available for | |
1382 | * reading. | |
1383 | * For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor | |
1384 | * will be reported as available for writing. | |
1385 | * | |
1386 | * The return values from this function are intended to be directly returned | |
1387 | * from poll handler in driver. | |
1388 | */ | |
1389 | unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait) | |
1390 | { | |
1391 | unsigned long flags; | |
b25748fe | 1392 | unsigned int ret; |
e23ccc0a PO |
1393 | struct vb2_buffer *vb = NULL; |
1394 | ||
b25748fe | 1395 | /* |
4ffabdb3 | 1396 | * Start file I/O emulator only if streaming API has not been used yet. |
b25748fe MS |
1397 | */ |
1398 | if (q->num_buffers == 0 && q->fileio == NULL) { | |
1399 | if (!V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_READ)) { | |
1400 | ret = __vb2_init_fileio(q, 1); | |
1401 | if (ret) | |
4ffabdb3 | 1402 | return POLLERR; |
b25748fe MS |
1403 | } |
1404 | if (V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_WRITE)) { | |
1405 | ret = __vb2_init_fileio(q, 0); | |
1406 | if (ret) | |
4ffabdb3 | 1407 | return POLLERR; |
b25748fe MS |
1408 | /* |
1409 | * Write to OUTPUT queue can be done immediately. | |
1410 | */ | |
1411 | return POLLOUT | POLLWRNORM; | |
1412 | } | |
1413 | } | |
1414 | ||
e23ccc0a PO |
1415 | /* |
1416 | * There is nothing to wait for if no buffers have already been queued. | |
1417 | */ | |
1418 | if (list_empty(&q->queued_list)) | |
1419 | return POLLERR; | |
1420 | ||
1421 | poll_wait(file, &q->done_wq, wait); | |
1422 | ||
1423 | /* | |
1424 | * Take first buffer available for dequeuing. | |
1425 | */ | |
1426 | spin_lock_irqsave(&q->done_lock, flags); | |
1427 | if (!list_empty(&q->done_list)) | |
1428 | vb = list_first_entry(&q->done_list, struct vb2_buffer, | |
1429 | done_entry); | |
1430 | spin_unlock_irqrestore(&q->done_lock, flags); | |
1431 | ||
1432 | if (vb && (vb->state == VB2_BUF_STATE_DONE | |
1433 | || vb->state == VB2_BUF_STATE_ERROR)) { | |
1434 | return (V4L2_TYPE_IS_OUTPUT(q->type)) ? POLLOUT | POLLWRNORM : | |
1435 | POLLIN | POLLRDNORM; | |
1436 | } | |
1437 | return 0; | |
1438 | } | |
1439 | EXPORT_SYMBOL_GPL(vb2_poll); | |
1440 | ||
1441 | /** | |
1442 | * vb2_queue_init() - initialize a videobuf2 queue | |
1443 | * @q: videobuf2 queue; this structure should be allocated in driver | |
1444 | * | |
1445 | * The vb2_queue structure should be allocated by the driver. The driver is | |
1446 | * responsible of clearing it's content and setting initial values for some | |
1447 | * required entries before calling this function. | |
1448 | * q->ops, q->mem_ops, q->type and q->io_modes are mandatory. Please refer | |
1449 | * to the struct vb2_queue description in include/media/videobuf2-core.h | |
1450 | * for more information. | |
1451 | */ | |
1452 | int vb2_queue_init(struct vb2_queue *q) | |
1453 | { | |
1454 | BUG_ON(!q); | |
1455 | BUG_ON(!q->ops); | |
1456 | BUG_ON(!q->mem_ops); | |
1457 | BUG_ON(!q->type); | |
1458 | BUG_ON(!q->io_modes); | |
1459 | ||
1460 | BUG_ON(!q->ops->queue_setup); | |
1461 | BUG_ON(!q->ops->buf_queue); | |
1462 | ||
1463 | INIT_LIST_HEAD(&q->queued_list); | |
1464 | INIT_LIST_HEAD(&q->done_list); | |
1465 | spin_lock_init(&q->done_lock); | |
1466 | init_waitqueue_head(&q->done_wq); | |
1467 | ||
1468 | if (q->buf_struct_size == 0) | |
1469 | q->buf_struct_size = sizeof(struct vb2_buffer); | |
1470 | ||
1471 | return 0; | |
1472 | } | |
1473 | EXPORT_SYMBOL_GPL(vb2_queue_init); | |
1474 | ||
1475 | /** | |
1476 | * vb2_queue_release() - stop streaming, release the queue and free memory | |
1477 | * @q: videobuf2 queue | |
1478 | * | |
1479 | * This function stops streaming and performs necessary clean ups, including | |
1480 | * freeing video buffer memory. The driver is responsible for freeing | |
1481 | * the vb2_queue structure itself. | |
1482 | */ | |
1483 | void vb2_queue_release(struct vb2_queue *q) | |
1484 | { | |
b25748fe | 1485 | __vb2_cleanup_fileio(q); |
e23ccc0a PO |
1486 | __vb2_queue_cancel(q); |
1487 | __vb2_queue_free(q); | |
1488 | } | |
1489 | EXPORT_SYMBOL_GPL(vb2_queue_release); | |
1490 | ||
b25748fe MS |
1491 | /** |
1492 | * struct vb2_fileio_buf - buffer context used by file io emulator | |
1493 | * | |
1494 | * vb2 provides a compatibility layer and emulator of file io (read and | |
1495 | * write) calls on top of streaming API. This structure is used for | |
1496 | * tracking context related to the buffers. | |
1497 | */ | |
1498 | struct vb2_fileio_buf { | |
1499 | void *vaddr; | |
1500 | unsigned int size; | |
1501 | unsigned int pos; | |
1502 | unsigned int queued:1; | |
1503 | }; | |
1504 | ||
1505 | /** | |
1506 | * struct vb2_fileio_data - queue context used by file io emulator | |
1507 | * | |
1508 | * vb2 provides a compatibility layer and emulator of file io (read and | |
1509 | * write) calls on top of streaming API. For proper operation it required | |
1510 | * this structure to save the driver state between each call of the read | |
1511 | * or write function. | |
1512 | */ | |
1513 | struct vb2_fileio_data { | |
1514 | struct v4l2_requestbuffers req; | |
1515 | struct v4l2_buffer b; | |
1516 | struct vb2_fileio_buf bufs[VIDEO_MAX_FRAME]; | |
1517 | unsigned int index; | |
1518 | unsigned int q_count; | |
1519 | unsigned int dq_count; | |
1520 | unsigned int flags; | |
1521 | }; | |
1522 | ||
1523 | /** | |
1524 | * __vb2_init_fileio() - initialize file io emulator | |
1525 | * @q: videobuf2 queue | |
1526 | * @read: mode selector (1 means read, 0 means write) | |
1527 | */ | |
1528 | static int __vb2_init_fileio(struct vb2_queue *q, int read) | |
1529 | { | |
1530 | struct vb2_fileio_data *fileio; | |
1531 | int i, ret; | |
1532 | unsigned int count = 0; | |
1533 | ||
1534 | /* | |
1535 | * Sanity check | |
1536 | */ | |
1537 | if ((read && !(q->io_modes & VB2_READ)) || | |
1538 | (!read && !(q->io_modes & VB2_WRITE))) | |
1539 | BUG(); | |
1540 | ||
1541 | /* | |
1542 | * Check if device supports mapping buffers to kernel virtual space. | |
1543 | */ | |
1544 | if (!q->mem_ops->vaddr) | |
1545 | return -EBUSY; | |
1546 | ||
1547 | /* | |
1548 | * Check if streaming api has not been already activated. | |
1549 | */ | |
1550 | if (q->streaming || q->num_buffers > 0) | |
1551 | return -EBUSY; | |
1552 | ||
1553 | /* | |
1554 | * Start with count 1, driver can increase it in queue_setup() | |
1555 | */ | |
1556 | count = 1; | |
1557 | ||
1558 | dprintk(3, "setting up file io: mode %s, count %d, flags %08x\n", | |
1559 | (read) ? "read" : "write", count, q->io_flags); | |
1560 | ||
1561 | fileio = kzalloc(sizeof(struct vb2_fileio_data), GFP_KERNEL); | |
1562 | if (fileio == NULL) | |
1563 | return -ENOMEM; | |
1564 | ||
1565 | fileio->flags = q->io_flags; | |
1566 | ||
1567 | /* | |
1568 | * Request buffers and use MMAP type to force driver | |
1569 | * to allocate buffers by itself. | |
1570 | */ | |
1571 | fileio->req.count = count; | |
1572 | fileio->req.memory = V4L2_MEMORY_MMAP; | |
1573 | fileio->req.type = q->type; | |
1574 | ret = vb2_reqbufs(q, &fileio->req); | |
1575 | if (ret) | |
1576 | goto err_kfree; | |
1577 | ||
1578 | /* | |
1579 | * Check if plane_count is correct | |
1580 | * (multiplane buffers are not supported). | |
1581 | */ | |
1582 | if (q->bufs[0]->num_planes != 1) { | |
1583 | fileio->req.count = 0; | |
1584 | ret = -EBUSY; | |
1585 | goto err_reqbufs; | |
1586 | } | |
1587 | ||
1588 | /* | |
1589 | * Get kernel address of each buffer. | |
1590 | */ | |
1591 | for (i = 0; i < q->num_buffers; i++) { | |
1592 | fileio->bufs[i].vaddr = vb2_plane_vaddr(q->bufs[i], 0); | |
1593 | if (fileio->bufs[i].vaddr == NULL) | |
1594 | goto err_reqbufs; | |
1595 | fileio->bufs[i].size = vb2_plane_size(q->bufs[i], 0); | |
1596 | } | |
1597 | ||
1598 | /* | |
1599 | * Read mode requires pre queuing of all buffers. | |
1600 | */ | |
1601 | if (read) { | |
1602 | /* | |
1603 | * Queue all buffers. | |
1604 | */ | |
1605 | for (i = 0; i < q->num_buffers; i++) { | |
1606 | struct v4l2_buffer *b = &fileio->b; | |
1607 | memset(b, 0, sizeof(*b)); | |
1608 | b->type = q->type; | |
1609 | b->memory = q->memory; | |
1610 | b->index = i; | |
1611 | ret = vb2_qbuf(q, b); | |
1612 | if (ret) | |
1613 | goto err_reqbufs; | |
1614 | fileio->bufs[i].queued = 1; | |
1615 | } | |
1616 | ||
1617 | /* | |
1618 | * Start streaming. | |
1619 | */ | |
1620 | ret = vb2_streamon(q, q->type); | |
1621 | if (ret) | |
1622 | goto err_reqbufs; | |
1623 | } | |
1624 | ||
1625 | q->fileio = fileio; | |
1626 | ||
1627 | return ret; | |
1628 | ||
1629 | err_reqbufs: | |
1630 | vb2_reqbufs(q, &fileio->req); | |
1631 | ||
1632 | err_kfree: | |
1633 | kfree(fileio); | |
1634 | return ret; | |
1635 | } | |
1636 | ||
1637 | /** | |
1638 | * __vb2_cleanup_fileio() - free resourced used by file io emulator | |
1639 | * @q: videobuf2 queue | |
1640 | */ | |
1641 | static int __vb2_cleanup_fileio(struct vb2_queue *q) | |
1642 | { | |
1643 | struct vb2_fileio_data *fileio = q->fileio; | |
1644 | ||
1645 | if (fileio) { | |
1646 | /* | |
1647 | * Hack fileio context to enable direct calls to vb2 ioctl | |
1648 | * interface. | |
1649 | */ | |
1650 | q->fileio = NULL; | |
1651 | ||
1652 | vb2_streamoff(q, q->type); | |
1653 | fileio->req.count = 0; | |
1654 | vb2_reqbufs(q, &fileio->req); | |
1655 | kfree(fileio); | |
1656 | dprintk(3, "file io emulator closed\n"); | |
1657 | } | |
1658 | return 0; | |
1659 | } | |
1660 | ||
1661 | /** | |
1662 | * __vb2_perform_fileio() - perform a single file io (read or write) operation | |
1663 | * @q: videobuf2 queue | |
1664 | * @data: pointed to target userspace buffer | |
1665 | * @count: number of bytes to read or write | |
1666 | * @ppos: file handle position tracking pointer | |
1667 | * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) | |
1668 | * @read: access mode selector (1 means read, 0 means write) | |
1669 | */ | |
1670 | static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_t count, | |
1671 | loff_t *ppos, int nonblock, int read) | |
1672 | { | |
1673 | struct vb2_fileio_data *fileio; | |
1674 | struct vb2_fileio_buf *buf; | |
1675 | int ret, index; | |
1676 | ||
08b99e26 | 1677 | dprintk(3, "file io: mode %s, offset %ld, count %zd, %sblocking\n", |
b25748fe MS |
1678 | read ? "read" : "write", (long)*ppos, count, |
1679 | nonblock ? "non" : ""); | |
1680 | ||
1681 | if (!data) | |
1682 | return -EINVAL; | |
1683 | ||
1684 | /* | |
1685 | * Initialize emulator on first call. | |
1686 | */ | |
1687 | if (!q->fileio) { | |
1688 | ret = __vb2_init_fileio(q, read); | |
1689 | dprintk(3, "file io: vb2_init_fileio result: %d\n", ret); | |
1690 | if (ret) | |
1691 | return ret; | |
1692 | } | |
1693 | fileio = q->fileio; | |
1694 | ||
1695 | /* | |
1696 | * Hack fileio context to enable direct calls to vb2 ioctl interface. | |
1697 | * The pointer will be restored before returning from this function. | |
1698 | */ | |
1699 | q->fileio = NULL; | |
1700 | ||
1701 | index = fileio->index; | |
1702 | buf = &fileio->bufs[index]; | |
1703 | ||
1704 | /* | |
1705 | * Check if we need to dequeue the buffer. | |
1706 | */ | |
1707 | if (buf->queued) { | |
1708 | struct vb2_buffer *vb; | |
1709 | ||
1710 | /* | |
1711 | * Call vb2_dqbuf to get buffer back. | |
1712 | */ | |
1713 | memset(&fileio->b, 0, sizeof(fileio->b)); | |
1714 | fileio->b.type = q->type; | |
1715 | fileio->b.memory = q->memory; | |
1716 | fileio->b.index = index; | |
1717 | ret = vb2_dqbuf(q, &fileio->b, nonblock); | |
1718 | dprintk(5, "file io: vb2_dqbuf result: %d\n", ret); | |
1719 | if (ret) | |
1720 | goto end; | |
1721 | fileio->dq_count += 1; | |
1722 | ||
1723 | /* | |
1724 | * Get number of bytes filled by the driver | |
1725 | */ | |
1726 | vb = q->bufs[index]; | |
1727 | buf->size = vb2_get_plane_payload(vb, 0); | |
1728 | buf->queued = 0; | |
1729 | } | |
1730 | ||
1731 | /* | |
1732 | * Limit count on last few bytes of the buffer. | |
1733 | */ | |
1734 | if (buf->pos + count > buf->size) { | |
1735 | count = buf->size - buf->pos; | |
08b99e26 | 1736 | dprintk(5, "reducing read count: %zd\n", count); |
b25748fe MS |
1737 | } |
1738 | ||
1739 | /* | |
1740 | * Transfer data to userspace. | |
1741 | */ | |
08b99e26 | 1742 | dprintk(3, "file io: copying %zd bytes - buffer %d, offset %u\n", |
b25748fe MS |
1743 | count, index, buf->pos); |
1744 | if (read) | |
1745 | ret = copy_to_user(data, buf->vaddr + buf->pos, count); | |
1746 | else | |
1747 | ret = copy_from_user(buf->vaddr + buf->pos, data, count); | |
1748 | if (ret) { | |
1749 | dprintk(3, "file io: error copying data\n"); | |
1750 | ret = -EFAULT; | |
1751 | goto end; | |
1752 | } | |
1753 | ||
1754 | /* | |
1755 | * Update counters. | |
1756 | */ | |
1757 | buf->pos += count; | |
1758 | *ppos += count; | |
1759 | ||
1760 | /* | |
1761 | * Queue next buffer if required. | |
1762 | */ | |
1763 | if (buf->pos == buf->size || | |
1764 | (!read && (fileio->flags & VB2_FILEIO_WRITE_IMMEDIATELY))) { | |
1765 | /* | |
1766 | * Check if this is the last buffer to read. | |
1767 | */ | |
1768 | if (read && (fileio->flags & VB2_FILEIO_READ_ONCE) && | |
1769 | fileio->dq_count == 1) { | |
1770 | dprintk(3, "file io: read limit reached\n"); | |
1771 | /* | |
1772 | * Restore fileio pointer and release the context. | |
1773 | */ | |
1774 | q->fileio = fileio; | |
1775 | return __vb2_cleanup_fileio(q); | |
1776 | } | |
1777 | ||
1778 | /* | |
1779 | * Call vb2_qbuf and give buffer to the driver. | |
1780 | */ | |
1781 | memset(&fileio->b, 0, sizeof(fileio->b)); | |
1782 | fileio->b.type = q->type; | |
1783 | fileio->b.memory = q->memory; | |
1784 | fileio->b.index = index; | |
1785 | fileio->b.bytesused = buf->pos; | |
1786 | ret = vb2_qbuf(q, &fileio->b); | |
1787 | dprintk(5, "file io: vb2_dbuf result: %d\n", ret); | |
1788 | if (ret) | |
1789 | goto end; | |
1790 | ||
1791 | /* | |
1792 | * Buffer has been queued, update the status | |
1793 | */ | |
1794 | buf->pos = 0; | |
1795 | buf->queued = 1; | |
1796 | buf->size = q->bufs[0]->v4l2_planes[0].length; | |
1797 | fileio->q_count += 1; | |
1798 | ||
1799 | /* | |
1800 | * Switch to the next buffer | |
1801 | */ | |
1802 | fileio->index = (index + 1) % q->num_buffers; | |
1803 | ||
1804 | /* | |
1805 | * Start streaming if required. | |
1806 | */ | |
1807 | if (!read && !q->streaming) { | |
1808 | ret = vb2_streamon(q, q->type); | |
1809 | if (ret) | |
1810 | goto end; | |
1811 | } | |
1812 | } | |
1813 | ||
1814 | /* | |
1815 | * Return proper number of bytes processed. | |
1816 | */ | |
1817 | if (ret == 0) | |
1818 | ret = count; | |
1819 | end: | |
1820 | /* | |
1821 | * Restore the fileio context and block vb2 ioctl interface. | |
1822 | */ | |
1823 | q->fileio = fileio; | |
1824 | return ret; | |
1825 | } | |
1826 | ||
1827 | size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, | |
1828 | loff_t *ppos, int nonblocking) | |
1829 | { | |
1830 | return __vb2_perform_fileio(q, data, count, ppos, nonblocking, 1); | |
1831 | } | |
1832 | EXPORT_SYMBOL_GPL(vb2_read); | |
1833 | ||
1834 | size_t vb2_write(struct vb2_queue *q, char __user *data, size_t count, | |
1835 | loff_t *ppos, int nonblocking) | |
1836 | { | |
1837 | return __vb2_perform_fileio(q, data, count, ppos, nonblocking, 0); | |
1838 | } | |
1839 | EXPORT_SYMBOL_GPL(vb2_write); | |
1840 | ||
e23ccc0a | 1841 | MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2"); |
95072084 | 1842 | MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski"); |
e23ccc0a | 1843 | MODULE_LICENSE("GPL"); |