1 /* 2 * videobuf2-core.c - video buffer 2 core framework 3 * 4 * Copyright (C) 2010 Samsung Electronics 5 * 6 * Author: Pawel Osciak <pawel@osciak.com> 7 * Marek Szyprowski <m.szyprowski@samsung.com> 8 * 9 * The vb2_thread implementation was based on code from videobuf-dvb.c: 10 * (c) 2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs] 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation. 15 */ 16 17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 18 19 #include <linux/err.h> 20 #include <linux/kernel.h> 21 #include <linux/module.h> 22 #include <linux/mm.h> 23 #include <linux/poll.h> 24 #include <linux/slab.h> 25 #include <linux/sched.h> 26 #include <linux/freezer.h> 27 #include <linux/kthread.h> 28 29 #include <media/videobuf2-core.h> 30 #include <media/v4l2-mc.h> 31 32 #include <trace/events/vb2.h> 33 34 static int debug; 35 module_param(debug, int, 0644); 36 37 #define dprintk(q, level, fmt, arg...) \ 38 do { \ 39 if (debug >= level) \ 40 pr_info("[%s] %s: " fmt, (q)->name, __func__, \ 41 ## arg); \ 42 } while (0) 43 44 #ifdef CONFIG_VIDEO_ADV_DEBUG 45 46 /* 47 * If advanced debugging is on, then count how often each op is called 48 * successfully, which can either be per-buffer or per-queue. 49 * 50 * This makes it easy to check that the 'init' and 'cleanup' 51 * (and variations thereof) stay balanced. 52 */ 53 54 #define log_memop(vb, op) \ 55 dprintk((vb)->vb2_queue, 2, "call_memop(%d, %s)%s\n", \ 56 (vb)->index, #op, \ 57 (vb)->vb2_queue->mem_ops->op ? "" : " (nop)") 58 59 #define call_memop(vb, op, args...) \ 60 ({ \ 61 struct vb2_queue *_q = (vb)->vb2_queue; \ 62 int err; \ 63 \ 64 log_memop(vb, op); \ 65 err = _q->mem_ops->op ? _q->mem_ops->op(args) : 0; \ 66 if (!err) \ 67 (vb)->cnt_mem_ ## op++; \ 68 err; \ 69 }) 70 71 #define call_ptr_memop(op, vb, args...) \ 72 ({ \ 73 struct vb2_queue *_q = (vb)->vb2_queue; \ 74 void *ptr; \ 75 \ 76 log_memop(vb, op); \ 77 ptr = _q->mem_ops->op ? _q->mem_ops->op(vb, args) : NULL; \ 78 if (!IS_ERR_OR_NULL(ptr)) \ 79 (vb)->cnt_mem_ ## op++; \ 80 ptr; \ 81 }) 82 83 #define call_void_memop(vb, op, args...) \ 84 ({ \ 85 struct vb2_queue *_q = (vb)->vb2_queue; \ 86 \ 87 log_memop(vb, op); \ 88 if (_q->mem_ops->op) \ 89 _q->mem_ops->op(args); \ 90 (vb)->cnt_mem_ ## op++; \ 91 }) 92 93 #define log_qop(q, op) \ 94 dprintk(q, 2, "call_qop(%s)%s\n", #op, \ 95 (q)->ops->op ? "" : " (nop)") 96 97 #define call_qop(q, op, args...) \ 98 ({ \ 99 int err; \ 100 \ 101 log_qop(q, op); \ 102 err = (q)->ops->op ? (q)->ops->op(args) : 0; \ 103 if (!err) \ 104 (q)->cnt_ ## op++; \ 105 err; \ 106 }) 107 108 #define call_void_qop(q, op, args...) \ 109 ({ \ 110 log_qop(q, op); \ 111 if ((q)->ops->op) \ 112 (q)->ops->op(args); \ 113 (q)->cnt_ ## op++; \ 114 }) 115 116 #define log_vb_qop(vb, op, args...) \ 117 dprintk((vb)->vb2_queue, 2, "call_vb_qop(%d, %s)%s\n", \ 118 (vb)->index, #op, \ 119 (vb)->vb2_queue->ops->op ? "" : " (nop)") 120 121 #define call_vb_qop(vb, op, args...) \ 122 ({ \ 123 int err; \ 124 \ 125 log_vb_qop(vb, op); \ 126 err = (vb)->vb2_queue->ops->op ? \ 127 (vb)->vb2_queue->ops->op(args) : 0; \ 128 if (!err) \ 129 (vb)->cnt_ ## op++; \ 130 err; \ 131 }) 132 133 #define call_void_vb_qop(vb, op, args...) \ 134 ({ \ 135 log_vb_qop(vb, op); \ 136 if ((vb)->vb2_queue->ops->op) \ 137 (vb)->vb2_queue->ops->op(args); \ 138 (vb)->cnt_ ## op++; \ 139 }) 140 141 #else 142 143 #define call_memop(vb, op, args...) \ 144 ((vb)->vb2_queue->mem_ops->op ? \ 145 (vb)->vb2_queue->mem_ops->op(args) : 0) 146 147 #define call_ptr_memop(op, vb, args...) \ 148 ((vb)->vb2_queue->mem_ops->op ? \ 149 (vb)->vb2_queue->mem_ops->op(vb, args) : NULL) 150 151 #define call_void_memop(vb, op, args...) \ 152 do { \ 153 if ((vb)->vb2_queue->mem_ops->op) \ 154 (vb)->vb2_queue->mem_ops->op(args); \ 155 } while (0) 156 157 #define call_qop(q, op, args...) \ 158 ((q)->ops->op ? (q)->ops->op(args) : 0) 159 160 #define call_void_qop(q, op, args...) \ 161 do { \ 162 if ((q)->ops->op) \ 163 (q)->ops->op(args); \ 164 } while (0) 165 166 #define call_vb_qop(vb, op, args...) \ 167 ((vb)->vb2_queue->ops->op ? (vb)->vb2_queue->ops->op(args) : 0) 168 169 #define call_void_vb_qop(vb, op, args...) \ 170 do { \ 171 if ((vb)->vb2_queue->ops->op) \ 172 (vb)->vb2_queue->ops->op(args); \ 173 } while (0) 174 175 #endif 176 177 #define call_bufop(q, op, args...) \ 178 ({ \ 179 int ret = 0; \ 180 if (q && q->buf_ops && q->buf_ops->op) \ 181 ret = q->buf_ops->op(args); \ 182 ret; \ 183 }) 184 185 #define call_void_bufop(q, op, args...) \ 186 ({ \ 187 if (q && q->buf_ops && q->buf_ops->op) \ 188 q->buf_ops->op(args); \ 189 }) 190 191 static void __vb2_queue_cancel(struct vb2_queue *q); 192 static void __enqueue_in_driver(struct vb2_buffer *vb); 193 194 static const char *vb2_state_name(enum vb2_buffer_state s) 195 { 196 static const char * const state_names[] = { 197 [VB2_BUF_STATE_DEQUEUED] = "dequeued", 198 [VB2_BUF_STATE_IN_REQUEST] = "in request", 199 [VB2_BUF_STATE_PREPARING] = "preparing", 200 [VB2_BUF_STATE_QUEUED] = "queued", 201 [VB2_BUF_STATE_ACTIVE] = "active", 202 [VB2_BUF_STATE_DONE] = "done", 203 [VB2_BUF_STATE_ERROR] = "error", 204 }; 205 206 if ((unsigned int)(s) < ARRAY_SIZE(state_names)) 207 return state_names[s]; 208 return "unknown"; 209 } 210 211 /* 212 * __vb2_buf_mem_alloc() - allocate video memory for the given buffer 213 */ 214 static int __vb2_buf_mem_alloc(struct vb2_buffer *vb) 215 { 216 struct vb2_queue *q = vb->vb2_queue; 217 void *mem_priv; 218 int plane; 219 int ret = -ENOMEM; 220 221 /* 222 * Allocate memory for all planes in this buffer 223 * NOTE: mmapped areas should be page aligned 224 */ 225 for (plane = 0; plane < vb->num_planes; ++plane) { 226 /* Memops alloc requires size to be page aligned. */ 227 unsigned long size = PAGE_ALIGN(vb->planes[plane].length); 228 229 /* Did it wrap around? */ 230 if (size < vb->planes[plane].length) 231 goto free; 232 233 mem_priv = call_ptr_memop(alloc, 234 vb, 235 q->alloc_devs[plane] ? : q->dev, 236 size); 237 if (IS_ERR_OR_NULL(mem_priv)) { 238 if (mem_priv) 239 ret = PTR_ERR(mem_priv); 240 goto free; 241 } 242 243 /* Associate allocator private data with this plane */ 244 vb->planes[plane].mem_priv = mem_priv; 245 } 246 247 return 0; 248 free: 249 /* Free already allocated memory if one of the allocations failed */ 250 for (; plane > 0; --plane) { 251 call_void_memop(vb, put, vb->planes[plane - 1].mem_priv); 252 vb->planes[plane - 1].mem_priv = NULL; 253 } 254 255 return ret; 256 } 257 258 /* 259 * __vb2_buf_mem_free() - free memory of the given buffer 260 */ 261 static void __vb2_buf_mem_free(struct vb2_buffer *vb) 262 { 263 unsigned int plane; 264 265 for (plane = 0; plane < vb->num_planes; ++plane) { 266 call_void_memop(vb, put, vb->planes[plane].mem_priv); 267 vb->planes[plane].mem_priv = NULL; 268 dprintk(vb->vb2_queue, 3, "freed plane %d of buffer %d\n", 269 plane, vb->index); 270 } 271 } 272 273 /* 274 * __vb2_buf_userptr_put() - release userspace memory associated with 275 * a USERPTR buffer 276 */ 277 static void __vb2_buf_userptr_put(struct vb2_buffer *vb) 278 { 279 unsigned int plane; 280 281 for (plane = 0; plane < vb->num_planes; ++plane) { 282 if (vb->planes[plane].mem_priv) 283 call_void_memop(vb, put_userptr, vb->planes[plane].mem_priv); 284 vb->planes[plane].mem_priv = NULL; 285 } 286 } 287 288 /* 289 * __vb2_plane_dmabuf_put() - release memory associated with 290 * a DMABUF shared plane 291 */ 292 static void __vb2_plane_dmabuf_put(struct vb2_buffer *vb, struct vb2_plane *p) 293 { 294 if (!p->mem_priv) 295 return; 296 297 if (p->dbuf_mapped) 298 call_void_memop(vb, unmap_dmabuf, p->mem_priv); 299 300 call_void_memop(vb, detach_dmabuf, p->mem_priv); 301 dma_buf_put(p->dbuf); 302 p->mem_priv = NULL; 303 p->dbuf = NULL; 304 p->dbuf_mapped = 0; 305 } 306 307 /* 308 * __vb2_buf_dmabuf_put() - release memory associated with 309 * a DMABUF shared buffer 310 */ 311 static void __vb2_buf_dmabuf_put(struct vb2_buffer *vb) 312 { 313 unsigned int plane; 314 315 for (plane = 0; plane < vb->num_planes; ++plane) 316 __vb2_plane_dmabuf_put(vb, &vb->planes[plane]); 317 } 318 319 /* 320 * __vb2_buf_mem_prepare() - call ->prepare() on buffer's private memory 321 * to sync caches 322 */ 323 static void __vb2_buf_mem_prepare(struct vb2_buffer *vb) 324 { 325 unsigned int plane; 326 327 if (vb->synced) 328 return; 329 330 vb->synced = 1; 331 for (plane = 0; plane < vb->num_planes; ++plane) 332 call_void_memop(vb, prepare, vb->planes[plane].mem_priv); 333 } 334 335 /* 336 * __vb2_buf_mem_finish() - call ->finish on buffer's private memory 337 * to sync caches 338 */ 339 static void __vb2_buf_mem_finish(struct vb2_buffer *vb) 340 { 341 unsigned int plane; 342 343 if (!vb->synced) 344 return; 345 346 vb->synced = 0; 347 for (plane = 0; plane < vb->num_planes; ++plane) 348 call_void_memop(vb, finish, vb->planes[plane].mem_priv); 349 } 350 351 /* 352 * __setup_offsets() - setup unique offsets ("cookies") for every plane in 353 * the buffer. 354 */ 355 static void __setup_offsets(struct vb2_buffer *vb) 356 { 357 struct vb2_queue *q = vb->vb2_queue; 358 unsigned int plane; 359 unsigned long off = 0; 360 361 if (vb->index) { 362 struct vb2_buffer *prev = q->bufs[vb->index - 1]; 363 struct vb2_plane *p = &prev->planes[prev->num_planes - 1]; 364 365 off = PAGE_ALIGN(p->m.offset + p->length); 366 } 367 368 for (plane = 0; plane < vb->num_planes; ++plane) { 369 vb->planes[plane].m.offset = off; 370 371 dprintk(q, 3, "buffer %d, plane %d offset 0x%08lx\n", 372 vb->index, plane, off); 373 374 off += vb->planes[plane].length; 375 off = PAGE_ALIGN(off); 376 } 377 } 378 379 static void init_buffer_cache_hints(struct vb2_queue *q, struct vb2_buffer *vb) 380 { 381 /* 382 * DMA exporter should take care of cache syncs, so we can avoid 383 * explicit ->prepare()/->finish() syncs. For other ->memory types 384 * we always need ->prepare() or/and ->finish() cache sync. 385 */ 386 if (q->memory == VB2_MEMORY_DMABUF) { 387 vb->skip_cache_sync_on_finish = 1; 388 vb->skip_cache_sync_on_prepare = 1; 389 return; 390 } 391 392 /* 393 * ->finish() cache sync can be avoided when queue direction is 394 * TO_DEVICE. 395 */ 396 if (q->dma_dir == DMA_TO_DEVICE) 397 vb->skip_cache_sync_on_finish = 1; 398 } 399 400 /* 401 * __vb2_queue_alloc() - allocate videobuf buffer structures and (for MMAP type) 402 * video buffer memory for all buffers/planes on the queue and initializes the 403 * queue 404 * 405 * Returns the number of buffers successfully allocated. 406 */ 407 static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, 408 unsigned int num_buffers, unsigned int num_planes, 409 const unsigned plane_sizes[VB2_MAX_PLANES]) 410 { 411 unsigned int buffer, plane; 412 struct vb2_buffer *vb; 413 int ret; 414 415 /* Ensure that q->num_buffers+num_buffers is below VB2_MAX_FRAME */ 416 num_buffers = min_t(unsigned int, num_buffers, 417 VB2_MAX_FRAME - q->num_buffers); 418 419 for (buffer = 0; buffer < num_buffers; ++buffer) { 420 /* Allocate videobuf buffer structures */ 421 vb = kzalloc(q->buf_struct_size, GFP_KERNEL); 422 if (!vb) { 423 dprintk(q, 1, "memory alloc for buffer struct failed\n"); 424 break; 425 } 426 427 vb->state = VB2_BUF_STATE_DEQUEUED; 428 vb->vb2_queue = q; 429 vb->num_planes = num_planes; 430 vb->index = q->num_buffers + buffer; 431 vb->type = q->type; 432 vb->memory = memory; 433 init_buffer_cache_hints(q, vb); 434 for (plane = 0; plane < num_planes; ++plane) { 435 vb->planes[plane].length = plane_sizes[plane]; 436 vb->planes[plane].min_length = plane_sizes[plane]; 437 } 438 call_void_bufop(q, init_buffer, vb); 439 440 q->bufs[vb->index] = vb; 441 442 /* Allocate video buffer memory for the MMAP type */ 443 if (memory == VB2_MEMORY_MMAP) { 444 ret = __vb2_buf_mem_alloc(vb); 445 if (ret) { 446 dprintk(q, 1, "failed allocating memory for buffer %d\n", 447 buffer); 448 q->bufs[vb->index] = NULL; 449 kfree(vb); 450 break; 451 } 452 __setup_offsets(vb); 453 /* 454 * Call the driver-provided buffer initialization 455 * callback, if given. An error in initialization 456 * results in queue setup failure. 457 */ 458 ret = call_vb_qop(vb, buf_init, vb); 459 if (ret) { 460 dprintk(q, 1, "buffer %d %p initialization failed\n", 461 buffer, vb); 462 __vb2_buf_mem_free(vb); 463 q->bufs[vb->index] = NULL; 464 kfree(vb); 465 break; 466 } 467 } 468 } 469 470 dprintk(q, 3, "allocated %d buffers, %d plane(s) each\n", 471 buffer, num_planes); 472 473 return buffer; 474 } 475 476 /* 477 * __vb2_free_mem() - release all video buffer memory for a given queue 478 */ 479 static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers) 480 { 481 unsigned int buffer; 482 struct vb2_buffer *vb; 483 484 for (buffer = q->num_buffers - buffers; buffer < q->num_buffers; 485 ++buffer) { 486 vb = q->bufs[buffer]; 487 if (!vb) 488 continue; 489 490 /* Free MMAP buffers or release USERPTR buffers */ 491 if (q->memory == VB2_MEMORY_MMAP) 492 __vb2_buf_mem_free(vb); 493 else if (q->memory == VB2_MEMORY_DMABUF) 494 __vb2_buf_dmabuf_put(vb); 495 else 496 __vb2_buf_userptr_put(vb); 497 } 498 } 499 500 /* 501 * __vb2_queue_free() - free buffers at the end of the queue - video memory and 502 * related information, if no buffers are left return the queue to an 503 * uninitialized state. Might be called even if the queue has already been freed. 504 */ 505 static int __vb2_queue_free(struct vb2_queue *q, unsigned int buffers) 506 { 507 unsigned int buffer; 508 509 /* 510 * Sanity check: when preparing a buffer the queue lock is released for 511 * a short while (see __buf_prepare for the details), which would allow 512 * a race with a reqbufs which can call this function. Removing the 513 * buffers from underneath __buf_prepare is obviously a bad idea, so we 514 * check if any of the buffers is in the state PREPARING, and if so we 515 * just return -EAGAIN. 516 */ 517 for (buffer = q->num_buffers - buffers; buffer < q->num_buffers; 518 ++buffer) { 519 if (q->bufs[buffer] == NULL) 520 continue; 521 if (q->bufs[buffer]->state == VB2_BUF_STATE_PREPARING) { 522 dprintk(q, 1, "preparing buffers, cannot free\n"); 523 return -EAGAIN; 524 } 525 } 526 527 /* Call driver-provided cleanup function for each buffer, if provided */ 528 for (buffer = q->num_buffers - buffers; buffer < q->num_buffers; 529 ++buffer) { 530 struct vb2_buffer *vb = q->bufs[buffer]; 531 532 if (vb && vb->planes[0].mem_priv) 533 call_void_vb_qop(vb, buf_cleanup, vb); 534 } 535 536 /* Release video buffer memory */ 537 __vb2_free_mem(q, buffers); 538 539 #ifdef CONFIG_VIDEO_ADV_DEBUG 540 /* 541 * Check that all the calls were balances during the life-time of this 542 * queue. If not (or if the debug level is 1 or up), then dump the 543 * counters to the kernel log. 544 */ 545 if (q->num_buffers) { 546 bool unbalanced = q->cnt_start_streaming != q->cnt_stop_streaming || 547 q->cnt_wait_prepare != q->cnt_wait_finish; 548 549 if (unbalanced || debug) { 550 pr_info("counters for queue %p:%s\n", q, 551 unbalanced ? " UNBALANCED!" : ""); 552 pr_info(" setup: %u start_streaming: %u stop_streaming: %u\n", 553 q->cnt_queue_setup, q->cnt_start_streaming, 554 q->cnt_stop_streaming); 555 pr_info(" wait_prepare: %u wait_finish: %u\n", 556 q->cnt_wait_prepare, q->cnt_wait_finish); 557 } 558 q->cnt_queue_setup = 0; 559 q->cnt_wait_prepare = 0; 560 q->cnt_wait_finish = 0; 561 q->cnt_start_streaming = 0; 562 q->cnt_stop_streaming = 0; 563 } 564 for (buffer = 0; buffer < q->num_buffers; ++buffer) { 565 struct vb2_buffer *vb = q->bufs[buffer]; 566 bool unbalanced = vb->cnt_mem_alloc != vb->cnt_mem_put || 567 vb->cnt_mem_prepare != vb->cnt_mem_finish || 568 vb->cnt_mem_get_userptr != vb->cnt_mem_put_userptr || 569 vb->cnt_mem_attach_dmabuf != vb->cnt_mem_detach_dmabuf || 570 vb->cnt_mem_map_dmabuf != vb->cnt_mem_unmap_dmabuf || 571 vb->cnt_buf_queue != vb->cnt_buf_done || 572 vb->cnt_buf_prepare != vb->cnt_buf_finish || 573 vb->cnt_buf_init != vb->cnt_buf_cleanup; 574 575 if (unbalanced || debug) { 576 pr_info(" counters for queue %p, buffer %d:%s\n", 577 q, buffer, unbalanced ? " UNBALANCED!" : ""); 578 pr_info(" buf_init: %u buf_cleanup: %u buf_prepare: %u buf_finish: %u\n", 579 vb->cnt_buf_init, vb->cnt_buf_cleanup, 580 vb->cnt_buf_prepare, vb->cnt_buf_finish); 581 pr_info(" buf_out_validate: %u buf_queue: %u buf_done: %u buf_request_complete: %u\n", 582 vb->cnt_buf_out_validate, vb->cnt_buf_queue, 583 vb->cnt_buf_done, vb->cnt_buf_request_complete); 584 pr_info(" alloc: %u put: %u prepare: %u finish: %u mmap: %u\n", 585 vb->cnt_mem_alloc, vb->cnt_mem_put, 586 vb->cnt_mem_prepare, vb->cnt_mem_finish, 587 vb->cnt_mem_mmap); 588 pr_info(" get_userptr: %u put_userptr: %u\n", 589 vb->cnt_mem_get_userptr, vb->cnt_mem_put_userptr); 590 pr_info(" attach_dmabuf: %u detach_dmabuf: %u map_dmabuf: %u unmap_dmabuf: %u\n", 591 vb->cnt_mem_attach_dmabuf, vb->cnt_mem_detach_dmabuf, 592 vb->cnt_mem_map_dmabuf, vb->cnt_mem_unmap_dmabuf); 593 pr_info(" get_dmabuf: %u num_users: %u vaddr: %u cookie: %u\n", 594 vb->cnt_mem_get_dmabuf, 595 vb->cnt_mem_num_users, 596 vb->cnt_mem_vaddr, 597 vb->cnt_mem_cookie); 598 } 599 } 600 #endif 601 602 /* Free videobuf buffers */ 603 for (buffer = q->num_buffers - buffers; buffer < q->num_buffers; 604 ++buffer) { 605 kfree(q->bufs[buffer]); 606 q->bufs[buffer] = NULL; 607 } 608 609 q->num_buffers -= buffers; 610 if (!q->num_buffers) { 611 q->memory = VB2_MEMORY_UNKNOWN; 612 INIT_LIST_HEAD(&q->queued_list); 613 } 614 return 0; 615 } 616 617 bool vb2_buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb) 618 { 619 unsigned int plane; 620 for (plane = 0; plane < vb->num_planes; ++plane) { 621 void *mem_priv = vb->planes[plane].mem_priv; 622 /* 623 * If num_users() has not been provided, call_memop 624 * will return 0, apparently nobody cares about this 625 * case anyway. If num_users() returns more than 1, 626 * we are not the only user of the plane's memory. 627 */ 628 if (mem_priv && call_memop(vb, num_users, mem_priv) > 1) 629 return true; 630 } 631 return false; 632 } 633 EXPORT_SYMBOL(vb2_buffer_in_use); 634 635 /* 636 * __buffers_in_use() - return true if any buffers on the queue are in use and 637 * the queue cannot be freed (by the means of REQBUFS(0)) call 638 */ 639 static bool __buffers_in_use(struct vb2_queue *q) 640 { 641 unsigned int buffer; 642 for (buffer = 0; buffer < q->num_buffers; ++buffer) { 643 if (vb2_buffer_in_use(q, q->bufs[buffer])) 644 return true; 645 } 646 return false; 647 } 648 649 void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb) 650 { 651 call_void_bufop(q, fill_user_buffer, q->bufs[index], pb); 652 } 653 EXPORT_SYMBOL_GPL(vb2_core_querybuf); 654 655 /* 656 * __verify_userptr_ops() - verify that all memory operations required for 657 * USERPTR queue type have been provided 658 */ 659 static int __verify_userptr_ops(struct vb2_queue *q) 660 { 661 if (!(q->io_modes & VB2_USERPTR) || !q->mem_ops->get_userptr || 662 !q->mem_ops->put_userptr) 663 return -EINVAL; 664 665 return 0; 666 } 667 668 /* 669 * __verify_mmap_ops() - verify that all memory operations required for 670 * MMAP queue type have been provided 671 */ 672 static int __verify_mmap_ops(struct vb2_queue *q) 673 { 674 if (!(q->io_modes & VB2_MMAP) || !q->mem_ops->alloc || 675 !q->mem_ops->put || !q->mem_ops->mmap) 676 return -EINVAL; 677 678 return 0; 679 } 680 681 /* 682 * __verify_dmabuf_ops() - verify that all memory operations required for 683 * DMABUF queue type have been provided 684 */ 685 static int __verify_dmabuf_ops(struct vb2_queue *q) 686 { 687 if (!(q->io_modes & VB2_DMABUF) || !q->mem_ops->attach_dmabuf || 688 !q->mem_ops->detach_dmabuf || !q->mem_ops->map_dmabuf || 689 !q->mem_ops->unmap_dmabuf) 690 return -EINVAL; 691 692 return 0; 693 } 694 695 int vb2_verify_memory_type(struct vb2_queue *q, 696 enum vb2_memory memory, unsigned int type) 697 { 698 if (memory != VB2_MEMORY_MMAP && memory != VB2_MEMORY_USERPTR && 699 memory != VB2_MEMORY_DMABUF) { 700 dprintk(q, 1, "unsupported memory type\n"); 701 return -EINVAL; 702 } 703 704 if (type != q->type) { 705 dprintk(q, 1, "requested type is incorrect\n"); 706 return -EINVAL; 707 } 708 709 /* 710 * Make sure all the required memory ops for given memory type 711 * are available. 712 */ 713 if (memory == VB2_MEMORY_MMAP && __verify_mmap_ops(q)) { 714 dprintk(q, 1, "MMAP for current setup unsupported\n"); 715 return -EINVAL; 716 } 717 718 if (memory == VB2_MEMORY_USERPTR && __verify_userptr_ops(q)) { 719 dprintk(q, 1, "USERPTR for current setup unsupported\n"); 720 return -EINVAL; 721 } 722 723 if (memory == VB2_MEMORY_DMABUF && __verify_dmabuf_ops(q)) { 724 dprintk(q, 1, "DMABUF for current setup unsupported\n"); 725 return -EINVAL; 726 } 727 728 /* 729 * Place the busy tests at the end: -EBUSY can be ignored when 730 * create_bufs is called with count == 0, but count == 0 should still 731 * do the memory and type validation. 732 */ 733 if (vb2_fileio_is_active(q)) { 734 dprintk(q, 1, "file io in progress\n"); 735 return -EBUSY; 736 } 737 return 0; 738 } 739 EXPORT_SYMBOL(vb2_verify_memory_type); 740 741 static void set_queue_coherency(struct vb2_queue *q, bool non_coherent_mem) 742 { 743 q->non_coherent_mem = 0; 744 745 if (!vb2_queue_allows_cache_hints(q)) 746 return; 747 q->non_coherent_mem = non_coherent_mem; 748 } 749 750 static bool verify_coherency_flags(struct vb2_queue *q, bool non_coherent_mem) 751 { 752 if (non_coherent_mem != q->non_coherent_mem) { 753 dprintk(q, 1, "memory coherency model mismatch\n"); 754 return false; 755 } 756 return true; 757 } 758 759 int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, 760 unsigned int flags, unsigned int *count) 761 { 762 unsigned int num_buffers, allocated_buffers, num_planes = 0; 763 unsigned plane_sizes[VB2_MAX_PLANES] = { }; 764 bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT; 765 unsigned int i; 766 int ret; 767 768 if (q->streaming) { 769 dprintk(q, 1, "streaming active\n"); 770 return -EBUSY; 771 } 772 773 if (q->waiting_in_dqbuf && *count) { 774 dprintk(q, 1, "another dup()ped fd is waiting for a buffer\n"); 775 return -EBUSY; 776 } 777 778 if (*count == 0 || q->num_buffers != 0 || 779 (q->memory != VB2_MEMORY_UNKNOWN && q->memory != memory) || 780 !verify_coherency_flags(q, non_coherent_mem)) { 781 /* 782 * We already have buffers allocated, so first check if they 783 * are not in use and can be freed. 784 */ 785 mutex_lock(&q->mmap_lock); 786 if (debug && q->memory == VB2_MEMORY_MMAP && 787 __buffers_in_use(q)) 788 dprintk(q, 1, "memory in use, orphaning buffers\n"); 789 790 /* 791 * Call queue_cancel to clean up any buffers in the 792 * QUEUED state which is possible if buffers were prepared or 793 * queued without ever calling STREAMON. 794 */ 795 __vb2_queue_cancel(q); 796 ret = __vb2_queue_free(q, q->num_buffers); 797 mutex_unlock(&q->mmap_lock); 798 if (ret) 799 return ret; 800 801 /* 802 * In case of REQBUFS(0) return immediately without calling 803 * driver's queue_setup() callback and allocating resources. 804 */ 805 if (*count == 0) 806 return 0; 807 } 808 809 /* 810 * Make sure the requested values and current defaults are sane. 811 */ 812 WARN_ON(q->min_buffers_needed > VB2_MAX_FRAME); 813 num_buffers = max_t(unsigned int, *count, q->min_buffers_needed); 814 num_buffers = min_t(unsigned int, num_buffers, VB2_MAX_FRAME); 815 memset(q->alloc_devs, 0, sizeof(q->alloc_devs)); 816 q->memory = memory; 817 set_queue_coherency(q, non_coherent_mem); 818 819 /* 820 * Ask the driver how many buffers and planes per buffer it requires. 821 * Driver also sets the size and allocator context for each plane. 822 */ 823 ret = call_qop(q, queue_setup, q, &num_buffers, &num_planes, 824 plane_sizes, q->alloc_devs); 825 if (ret) 826 return ret; 827 828 /* Check that driver has set sane values */ 829 if (WARN_ON(!num_planes)) 830 return -EINVAL; 831 832 for (i = 0; i < num_planes; i++) 833 if (WARN_ON(!plane_sizes[i])) 834 return -EINVAL; 835 836 /* Finally, allocate buffers and video memory */ 837 allocated_buffers = 838 __vb2_queue_alloc(q, memory, num_buffers, num_planes, plane_sizes); 839 if (allocated_buffers == 0) { 840 dprintk(q, 1, "memory allocation failed\n"); 841 return -ENOMEM; 842 } 843 844 /* 845 * There is no point in continuing if we can't allocate the minimum 846 * number of buffers needed by this vb2_queue. 847 */ 848 if (allocated_buffers < q->min_buffers_needed) 849 ret = -ENOMEM; 850 851 /* 852 * Check if driver can handle the allocated number of buffers. 853 */ 854 if (!ret && allocated_buffers < num_buffers) { 855 num_buffers = allocated_buffers; 856 /* 857 * num_planes is set by the previous queue_setup(), but since it 858 * signals to queue_setup() whether it is called from create_bufs() 859 * vs reqbufs() we zero it here to signal that queue_setup() is 860 * called for the reqbufs() case. 861 */ 862 num_planes = 0; 863 864 ret = call_qop(q, queue_setup, q, &num_buffers, 865 &num_planes, plane_sizes, q->alloc_devs); 866 867 if (!ret && allocated_buffers < num_buffers) 868 ret = -ENOMEM; 869 870 /* 871 * Either the driver has accepted a smaller number of buffers, 872 * or .queue_setup() returned an error 873 */ 874 } 875 876 mutex_lock(&q->mmap_lock); 877 q->num_buffers = allocated_buffers; 878 879 if (ret < 0) { 880 /* 881 * Note: __vb2_queue_free() will subtract 'allocated_buffers' 882 * from q->num_buffers. 883 */ 884 __vb2_queue_free(q, allocated_buffers); 885 mutex_unlock(&q->mmap_lock); 886 return ret; 887 } 888 mutex_unlock(&q->mmap_lock); 889 890 /* 891 * Return the number of successfully allocated buffers 892 * to the userspace. 893 */ 894 *count = allocated_buffers; 895 q->waiting_for_buffers = !q->is_output; 896 897 return 0; 898 } 899 EXPORT_SYMBOL_GPL(vb2_core_reqbufs); 900 901 int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, 902 unsigned int flags, unsigned int *count, 903 unsigned int requested_planes, 904 const unsigned int requested_sizes[]) 905 { 906 unsigned int num_planes = 0, num_buffers, allocated_buffers; 907 unsigned plane_sizes[VB2_MAX_PLANES] = { }; 908 bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT; 909 int ret; 910 911 if (q->num_buffers == VB2_MAX_FRAME) { 912 dprintk(q, 1, "maximum number of buffers already allocated\n"); 913 return -ENOBUFS; 914 } 915 916 if (!q->num_buffers) { 917 if (q->waiting_in_dqbuf && *count) { 918 dprintk(q, 1, "another dup()ped fd is waiting for a buffer\n"); 919 return -EBUSY; 920 } 921 memset(q->alloc_devs, 0, sizeof(q->alloc_devs)); 922 q->memory = memory; 923 q->waiting_for_buffers = !q->is_output; 924 set_queue_coherency(q, non_coherent_mem); 925 } else { 926 if (q->memory != memory) { 927 dprintk(q, 1, "memory model mismatch\n"); 928 return -EINVAL; 929 } 930 if (!verify_coherency_flags(q, non_coherent_mem)) 931 return -EINVAL; 932 } 933 934 num_buffers = min(*count, VB2_MAX_FRAME - q->num_buffers); 935 936 if (requested_planes && requested_sizes) { 937 num_planes = requested_planes; 938 memcpy(plane_sizes, requested_sizes, sizeof(plane_sizes)); 939 } 940 941 /* 942 * Ask the driver, whether the requested number of buffers, planes per 943 * buffer and their sizes are acceptable 944 */ 945 ret = call_qop(q, queue_setup, q, &num_buffers, 946 &num_planes, plane_sizes, q->alloc_devs); 947 if (ret) 948 return ret; 949 950 /* Finally, allocate buffers and video memory */ 951 allocated_buffers = __vb2_queue_alloc(q, memory, num_buffers, 952 num_planes, plane_sizes); 953 if (allocated_buffers == 0) { 954 dprintk(q, 1, "memory allocation failed\n"); 955 return -ENOMEM; 956 } 957 958 /* 959 * Check if driver can handle the so far allocated number of buffers. 960 */ 961 if (allocated_buffers < num_buffers) { 962 num_buffers = allocated_buffers; 963 964 /* 965 * q->num_buffers contains the total number of buffers, that the 966 * queue driver has set up 967 */ 968 ret = call_qop(q, queue_setup, q, &num_buffers, 969 &num_planes, plane_sizes, q->alloc_devs); 970 971 if (!ret && allocated_buffers < num_buffers) 972 ret = -ENOMEM; 973 974 /* 975 * Either the driver has accepted a smaller number of buffers, 976 * or .queue_setup() returned an error 977 */ 978 } 979 980 mutex_lock(&q->mmap_lock); 981 q->num_buffers += allocated_buffers; 982 983 if (ret < 0) { 984 /* 985 * Note: __vb2_queue_free() will subtract 'allocated_buffers' 986 * from q->num_buffers. 987 */ 988 __vb2_queue_free(q, allocated_buffers); 989 mutex_unlock(&q->mmap_lock); 990 return -ENOMEM; 991 } 992 mutex_unlock(&q->mmap_lock); 993 994 /* 995 * Return the number of successfully allocated buffers 996 * to the userspace. 997 */ 998 *count = allocated_buffers; 999 1000 return 0; 1001 } 1002 EXPORT_SYMBOL_GPL(vb2_core_create_bufs); 1003 1004 void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no) 1005 { 1006 if (plane_no >= vb->num_planes || !vb->planes[plane_no].mem_priv) 1007 return NULL; 1008 1009 return call_ptr_memop(vaddr, vb, vb->planes[plane_no].mem_priv); 1010 1011 } 1012 EXPORT_SYMBOL_GPL(vb2_plane_vaddr); 1013 1014 void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no) 1015 { 1016 if (plane_no >= vb->num_planes || !vb->planes[plane_no].mem_priv) 1017 return NULL; 1018 1019 return call_ptr_memop(cookie, vb, vb->planes[plane_no].mem_priv); 1020 } 1021 EXPORT_SYMBOL_GPL(vb2_plane_cookie); 1022 1023 void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state) 1024 { 1025 struct vb2_queue *q = vb->vb2_queue; 1026 unsigned long flags; 1027 1028 if (WARN_ON(vb->state != VB2_BUF_STATE_ACTIVE)) 1029 return; 1030 1031 if (WARN_ON(state != VB2_BUF_STATE_DONE && 1032 state != VB2_BUF_STATE_ERROR && 1033 state != VB2_BUF_STATE_QUEUED)) 1034 state = VB2_BUF_STATE_ERROR; 1035 1036 #ifdef CONFIG_VIDEO_ADV_DEBUG 1037 /* 1038 * Although this is not a callback, it still does have to balance 1039 * with the buf_queue op. So update this counter manually. 1040 */ 1041 vb->cnt_buf_done++; 1042 #endif 1043 dprintk(q, 4, "done processing on buffer %d, state: %s\n", 1044 vb->index, vb2_state_name(state)); 1045 1046 if (state != VB2_BUF_STATE_QUEUED) 1047 __vb2_buf_mem_finish(vb); 1048 1049 spin_lock_irqsave(&q->done_lock, flags); 1050 if (state == VB2_BUF_STATE_QUEUED) { 1051 vb->state = VB2_BUF_STATE_QUEUED; 1052 } else { 1053 /* Add the buffer to the done buffers list */ 1054 list_add_tail(&vb->done_entry, &q->done_list); 1055 vb->state = state; 1056 } 1057 atomic_dec(&q->owned_by_drv_count); 1058 1059 if (state != VB2_BUF_STATE_QUEUED && vb->req_obj.req) { 1060 media_request_object_unbind(&vb->req_obj); 1061 media_request_object_put(&vb->req_obj); 1062 } 1063 1064 spin_unlock_irqrestore(&q->done_lock, flags); 1065 1066 trace_vb2_buf_done(q, vb); 1067 1068 switch (state) { 1069 case VB2_BUF_STATE_QUEUED: 1070 return; 1071 default: 1072 /* Inform any processes that may be waiting for buffers */ 1073 wake_up(&q->done_wq); 1074 break; 1075 } 1076 } 1077 EXPORT_SYMBOL_GPL(vb2_buffer_done); 1078 1079 void vb2_discard_done(struct vb2_queue *q) 1080 { 1081 struct vb2_buffer *vb; 1082 unsigned long flags; 1083 1084 spin_lock_irqsave(&q->done_lock, flags); 1085 list_for_each_entry(vb, &q->done_list, done_entry) 1086 vb->state = VB2_BUF_STATE_ERROR; 1087 spin_unlock_irqrestore(&q->done_lock, flags); 1088 } 1089 EXPORT_SYMBOL_GPL(vb2_discard_done); 1090 1091 /* 1092 * __prepare_mmap() - prepare an MMAP buffer 1093 */ 1094 static int __prepare_mmap(struct vb2_buffer *vb) 1095 { 1096 int ret = 0; 1097 1098 ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, 1099 vb, vb->planes); 1100 return ret ? ret : call_vb_qop(vb, buf_prepare, vb); 1101 } 1102 1103 /* 1104 * __prepare_userptr() - prepare a USERPTR buffer 1105 */ 1106 static int __prepare_userptr(struct vb2_buffer *vb) 1107 { 1108 struct vb2_plane planes[VB2_MAX_PLANES]; 1109 struct vb2_queue *q = vb->vb2_queue; 1110 void *mem_priv; 1111 unsigned int plane; 1112 int ret = 0; 1113 bool reacquired = vb->planes[0].mem_priv == NULL; 1114 1115 memset(planes, 0, sizeof(planes[0]) * vb->num_planes); 1116 /* Copy relevant information provided by the userspace */ 1117 ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, 1118 vb, planes); 1119 if (ret) 1120 return ret; 1121 1122 for (plane = 0; plane < vb->num_planes; ++plane) { 1123 /* Skip the plane if already verified */ 1124 if (vb->planes[plane].m.userptr && 1125 vb->planes[plane].m.userptr == planes[plane].m.userptr 1126 && vb->planes[plane].length == planes[plane].length) 1127 continue; 1128 1129 dprintk(q, 3, "userspace address for plane %d changed, reacquiring memory\n", 1130 plane); 1131 1132 /* Check if the provided plane buffer is large enough */ 1133 if (planes[plane].length < vb->planes[plane].min_length) { 1134 dprintk(q, 1, "provided buffer size %u is less than setup size %u for plane %d\n", 1135 planes[plane].length, 1136 vb->planes[plane].min_length, 1137 plane); 1138 ret = -EINVAL; 1139 goto err; 1140 } 1141 1142 /* Release previously acquired memory if present */ 1143 if (vb->planes[plane].mem_priv) { 1144 if (!reacquired) { 1145 reacquired = true; 1146 vb->copied_timestamp = 0; 1147 call_void_vb_qop(vb, buf_cleanup, vb); 1148 } 1149 call_void_memop(vb, put_userptr, vb->planes[plane].mem_priv); 1150 } 1151 1152 vb->planes[plane].mem_priv = NULL; 1153 vb->planes[plane].bytesused = 0; 1154 vb->planes[plane].length = 0; 1155 vb->planes[plane].m.userptr = 0; 1156 vb->planes[plane].data_offset = 0; 1157 1158 /* Acquire each plane's memory */ 1159 mem_priv = call_ptr_memop(get_userptr, 1160 vb, 1161 q->alloc_devs[plane] ? : q->dev, 1162 planes[plane].m.userptr, 1163 planes[plane].length); 1164 if (IS_ERR(mem_priv)) { 1165 dprintk(q, 1, "failed acquiring userspace memory for plane %d\n", 1166 plane); 1167 ret = PTR_ERR(mem_priv); 1168 goto err; 1169 } 1170 vb->planes[plane].mem_priv = mem_priv; 1171 } 1172 1173 /* 1174 * Now that everything is in order, copy relevant information 1175 * provided by userspace. 1176 */ 1177 for (plane = 0; plane < vb->num_planes; ++plane) { 1178 vb->planes[plane].bytesused = planes[plane].bytesused; 1179 vb->planes[plane].length = planes[plane].length; 1180 vb->planes[plane].m.userptr = planes[plane].m.userptr; 1181 vb->planes[plane].data_offset = planes[plane].data_offset; 1182 } 1183 1184 if (reacquired) { 1185 /* 1186 * One or more planes changed, so we must call buf_init to do 1187 * the driver-specific initialization on the newly acquired 1188 * buffer, if provided. 1189 */ 1190 ret = call_vb_qop(vb, buf_init, vb); 1191 if (ret) { 1192 dprintk(q, 1, "buffer initialization failed\n"); 1193 goto err; 1194 } 1195 } 1196 1197 ret = call_vb_qop(vb, buf_prepare, vb); 1198 if (ret) { 1199 dprintk(q, 1, "buffer preparation failed\n"); 1200 call_void_vb_qop(vb, buf_cleanup, vb); 1201 goto err; 1202 } 1203 1204 return 0; 1205 err: 1206 /* In case of errors, release planes that were already acquired */ 1207 for (plane = 0; plane < vb->num_planes; ++plane) { 1208 if (vb->planes[plane].mem_priv) 1209 call_void_memop(vb, put_userptr, 1210 vb->planes[plane].mem_priv); 1211 vb->planes[plane].mem_priv = NULL; 1212 vb->planes[plane].m.userptr = 0; 1213 vb->planes[plane].length = 0; 1214 } 1215 1216 return ret; 1217 } 1218 1219 /* 1220 * __prepare_dmabuf() - prepare a DMABUF buffer 1221 */ 1222 static int __prepare_dmabuf(struct vb2_buffer *vb) 1223 { 1224 struct vb2_plane planes[VB2_MAX_PLANES]; 1225 struct vb2_queue *q = vb->vb2_queue; 1226 void *mem_priv; 1227 unsigned int plane; 1228 int ret = 0; 1229 bool reacquired = vb->planes[0].mem_priv == NULL; 1230 1231 memset(planes, 0, sizeof(planes[0]) * vb->num_planes); 1232 /* Copy relevant information provided by the userspace */ 1233 ret = call_bufop(vb->vb2_queue, fill_vb2_buffer, 1234 vb, planes); 1235 if (ret) 1236 return ret; 1237 1238 for (plane = 0; plane < vb->num_planes; ++plane) { 1239 struct dma_buf *dbuf = dma_buf_get(planes[plane].m.fd); 1240 1241 if (IS_ERR_OR_NULL(dbuf)) { 1242 dprintk(q, 1, "invalid dmabuf fd for plane %d\n", 1243 plane); 1244 ret = -EINVAL; 1245 goto err; 1246 } 1247 1248 /* use DMABUF size if length is not provided */ 1249 if (planes[plane].length == 0) 1250 planes[plane].length = dbuf->size; 1251 1252 if (planes[plane].length < vb->planes[plane].min_length) { 1253 dprintk(q, 1, "invalid dmabuf length %u for plane %d, minimum length %u\n", 1254 planes[plane].length, plane, 1255 vb->planes[plane].min_length); 1256 dma_buf_put(dbuf); 1257 ret = -EINVAL; 1258 goto err; 1259 } 1260 1261 /* Skip the plane if already verified */ 1262 if (dbuf == vb->planes[plane].dbuf && 1263 vb->planes[plane].length == planes[plane].length) { 1264 dma_buf_put(dbuf); 1265 continue; 1266 } 1267 1268 dprintk(q, 3, "buffer for plane %d changed\n", plane); 1269 1270 if (!reacquired) { 1271 reacquired = true; 1272 vb->copied_timestamp = 0; 1273 call_void_vb_qop(vb, buf_cleanup, vb); 1274 } 1275 1276 /* Release previously acquired memory if present */ 1277 __vb2_plane_dmabuf_put(vb, &vb->planes[plane]); 1278 vb->planes[plane].bytesused = 0; 1279 vb->planes[plane].length = 0; 1280 vb->planes[plane].m.fd = 0; 1281 vb->planes[plane].data_offset = 0; 1282 1283 /* Acquire each plane's memory */ 1284 mem_priv = call_ptr_memop(attach_dmabuf, 1285 vb, 1286 q->alloc_devs[plane] ? : q->dev, 1287 dbuf, 1288 planes[plane].length); 1289 if (IS_ERR(mem_priv)) { 1290 dprintk(q, 1, "failed to attach dmabuf\n"); 1291 ret = PTR_ERR(mem_priv); 1292 dma_buf_put(dbuf); 1293 goto err; 1294 } 1295 1296 vb->planes[plane].dbuf = dbuf; 1297 vb->planes[plane].mem_priv = mem_priv; 1298 } 1299 1300 /* 1301 * This pins the buffer(s) with dma_buf_map_attachment()). It's done 1302 * here instead just before the DMA, while queueing the buffer(s) so 1303 * userspace knows sooner rather than later if the dma-buf map fails. 1304 */ 1305 for (plane = 0; plane < vb->num_planes; ++plane) { 1306 if (vb->planes[plane].dbuf_mapped) 1307 continue; 1308 1309 ret = call_memop(vb, map_dmabuf, vb->planes[plane].mem_priv); 1310 if (ret) { 1311 dprintk(q, 1, "failed to map dmabuf for plane %d\n", 1312 plane); 1313 goto err; 1314 } 1315 vb->planes[plane].dbuf_mapped = 1; 1316 } 1317 1318 /* 1319 * Now that everything is in order, copy relevant information 1320 * provided by userspace. 1321 */ 1322 for (plane = 0; plane < vb->num_planes; ++plane) { 1323 vb->planes[plane].bytesused = planes[plane].bytesused; 1324 vb->planes[plane].length = planes[plane].length; 1325 vb->planes[plane].m.fd = planes[plane].m.fd; 1326 vb->planes[plane].data_offset = planes[plane].data_offset; 1327 } 1328 1329 if (reacquired) { 1330 /* 1331 * Call driver-specific initialization on the newly acquired buffer, 1332 * if provided. 1333 */ 1334 ret = call_vb_qop(vb, buf_init, vb); 1335 if (ret) { 1336 dprintk(q, 1, "buffer initialization failed\n"); 1337 goto err; 1338 } 1339 } 1340 1341 ret = call_vb_qop(vb, buf_prepare, vb); 1342 if (ret) { 1343 dprintk(q, 1, "buffer preparation failed\n"); 1344 call_void_vb_qop(vb, buf_cleanup, vb); 1345 goto err; 1346 } 1347 1348 return 0; 1349 err: 1350 /* In case of errors, release planes that were already acquired */ 1351 __vb2_buf_dmabuf_put(vb); 1352 1353 return ret; 1354 } 1355 1356 /* 1357 * __enqueue_in_driver() - enqueue a vb2_buffer in driver for processing 1358 */ 1359 static void __enqueue_in_driver(struct vb2_buffer *vb) 1360 { 1361 struct vb2_queue *q = vb->vb2_queue; 1362 1363 vb->state = VB2_BUF_STATE_ACTIVE; 1364 atomic_inc(&q->owned_by_drv_count); 1365 1366 trace_vb2_buf_queue(q, vb); 1367 1368 call_void_vb_qop(vb, buf_queue, vb); 1369 } 1370 1371 static int __buf_prepare(struct vb2_buffer *vb) 1372 { 1373 struct vb2_queue *q = vb->vb2_queue; 1374 enum vb2_buffer_state orig_state = vb->state; 1375 int ret; 1376 1377 if (q->error) { 1378 dprintk(q, 1, "fatal error occurred on queue\n"); 1379 return -EIO; 1380 } 1381 1382 if (vb->prepared) 1383 return 0; 1384 WARN_ON(vb->synced); 1385 1386 if (q->is_output) { 1387 ret = call_vb_qop(vb, buf_out_validate, vb); 1388 if (ret) { 1389 dprintk(q, 1, "buffer validation failed\n"); 1390 return ret; 1391 } 1392 } 1393 1394 vb->state = VB2_BUF_STATE_PREPARING; 1395 1396 switch (q->memory) { 1397 case VB2_MEMORY_MMAP: 1398 ret = __prepare_mmap(vb); 1399 break; 1400 case VB2_MEMORY_USERPTR: 1401 ret = __prepare_userptr(vb); 1402 break; 1403 case VB2_MEMORY_DMABUF: 1404 ret = __prepare_dmabuf(vb); 1405 break; 1406 default: 1407 WARN(1, "Invalid queue type\n"); 1408 ret = -EINVAL; 1409 break; 1410 } 1411 1412 if (ret) { 1413 dprintk(q, 1, "buffer preparation failed: %d\n", ret); 1414 vb->state = orig_state; 1415 return ret; 1416 } 1417 1418 __vb2_buf_mem_prepare(vb); 1419 vb->prepared = 1; 1420 vb->state = orig_state; 1421 1422 return 0; 1423 } 1424 1425 static int vb2_req_prepare(struct media_request_object *obj) 1426 { 1427 struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj); 1428 int ret; 1429 1430 if (WARN_ON(vb->state != VB2_BUF_STATE_IN_REQUEST)) 1431 return -EINVAL; 1432 1433 mutex_lock(vb->vb2_queue->lock); 1434 ret = __buf_prepare(vb); 1435 mutex_unlock(vb->vb2_queue->lock); 1436 return ret; 1437 } 1438 1439 static void __vb2_dqbuf(struct vb2_buffer *vb); 1440 1441 static void vb2_req_unprepare(struct media_request_object *obj) 1442 { 1443 struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj); 1444 1445 mutex_lock(vb->vb2_queue->lock); 1446 __vb2_dqbuf(vb); 1447 vb->state = VB2_BUF_STATE_IN_REQUEST; 1448 mutex_unlock(vb->vb2_queue->lock); 1449 WARN_ON(!vb->req_obj.req); 1450 } 1451 1452 int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb, 1453 struct media_request *req); 1454 1455 static void vb2_req_queue(struct media_request_object *obj) 1456 { 1457 struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj); 1458 int err; 1459 1460 mutex_lock(vb->vb2_queue->lock); 1461 /* 1462 * There is no method to propagate an error from vb2_core_qbuf(), 1463 * so if this returns a non-0 value, then WARN. 1464 * 1465 * The only exception is -EIO which is returned if q->error is 1466 * set. We just ignore that, and expect this will be caught the 1467 * next time vb2_req_prepare() is called. 1468 */ 1469 err = vb2_core_qbuf(vb->vb2_queue, vb->index, NULL, NULL); 1470 WARN_ON_ONCE(err && err != -EIO); 1471 mutex_unlock(vb->vb2_queue->lock); 1472 } 1473 1474 static void vb2_req_unbind(struct media_request_object *obj) 1475 { 1476 struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj); 1477 1478 if (vb->state == VB2_BUF_STATE_IN_REQUEST) 1479 call_void_bufop(vb->vb2_queue, init_buffer, vb); 1480 } 1481 1482 static void vb2_req_release(struct media_request_object *obj) 1483 { 1484 struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj); 1485 1486 if (vb->state == VB2_BUF_STATE_IN_REQUEST) { 1487 vb->state = VB2_BUF_STATE_DEQUEUED; 1488 if (vb->request) 1489 media_request_put(vb->request); 1490 vb->request = NULL; 1491 } 1492 } 1493 1494 static const struct media_request_object_ops vb2_core_req_ops = { 1495 .prepare = vb2_req_prepare, 1496 .unprepare = vb2_req_unprepare, 1497 .queue = vb2_req_queue, 1498 .unbind = vb2_req_unbind, 1499 .release = vb2_req_release, 1500 }; 1501 1502 bool vb2_request_object_is_buffer(struct media_request_object *obj) 1503 { 1504 return obj->ops == &vb2_core_req_ops; 1505 } 1506 EXPORT_SYMBOL_GPL(vb2_request_object_is_buffer); 1507 1508 unsigned int vb2_request_buffer_cnt(struct media_request *req) 1509 { 1510 struct media_request_object *obj; 1511 unsigned long flags; 1512 unsigned int buffer_cnt = 0; 1513 1514 spin_lock_irqsave(&req->lock, flags); 1515 list_for_each_entry(obj, &req->objects, list) 1516 if (vb2_request_object_is_buffer(obj)) 1517 buffer_cnt++; 1518 spin_unlock_irqrestore(&req->lock, flags); 1519 1520 return buffer_cnt; 1521 } 1522 EXPORT_SYMBOL_GPL(vb2_request_buffer_cnt); 1523 1524 int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb) 1525 { 1526 struct vb2_buffer *vb; 1527 int ret; 1528 1529 vb = q->bufs[index]; 1530 if (vb->state != VB2_BUF_STATE_DEQUEUED) { 1531 dprintk(q, 1, "invalid buffer state %s\n", 1532 vb2_state_name(vb->state)); 1533 return -EINVAL; 1534 } 1535 if (vb->prepared) { 1536 dprintk(q, 1, "buffer already prepared\n"); 1537 return -EINVAL; 1538 } 1539 1540 ret = __buf_prepare(vb); 1541 if (ret) 1542 return ret; 1543 1544 /* Fill buffer information for the userspace */ 1545 call_void_bufop(q, fill_user_buffer, vb, pb); 1546 1547 dprintk(q, 2, "prepare of buffer %d succeeded\n", vb->index); 1548 1549 return 0; 1550 } 1551 EXPORT_SYMBOL_GPL(vb2_core_prepare_buf); 1552 1553 /* 1554 * vb2_start_streaming() - Attempt to start streaming. 1555 * @q: videobuf2 queue 1556 * 1557 * Attempt to start streaming. When this function is called there must be 1558 * at least q->min_buffers_needed buffers queued up (i.e. the minimum 1559 * number of buffers required for the DMA engine to function). If the 1560 * @start_streaming op fails it is supposed to return all the driver-owned 1561 * buffers back to vb2 in state QUEUED. Check if that happened and if 1562 * not warn and reclaim them forcefully. 1563 */ 1564 static int vb2_start_streaming(struct vb2_queue *q) 1565 { 1566 struct vb2_buffer *vb; 1567 int ret; 1568 1569 /* 1570 * If any buffers were queued before streamon, 1571 * we can now pass them to driver for processing. 1572 */ 1573 list_for_each_entry(vb, &q->queued_list, queued_entry) 1574 __enqueue_in_driver(vb); 1575 1576 /* Tell the driver to start streaming */ 1577 q->start_streaming_called = 1; 1578 ret = call_qop(q, start_streaming, q, 1579 atomic_read(&q->owned_by_drv_count)); 1580 if (!ret) 1581 return 0; 1582 1583 q->start_streaming_called = 0; 1584 1585 dprintk(q, 1, "driver refused to start streaming\n"); 1586 /* 1587 * If you see this warning, then the driver isn't cleaning up properly 1588 * after a failed start_streaming(). See the start_streaming() 1589 * documentation in videobuf2-core.h for more information how buffers 1590 * should be returned to vb2 in start_streaming(). 1591 */ 1592 if (WARN_ON(atomic_read(&q->owned_by_drv_count))) { 1593 unsigned i; 1594 1595 /* 1596 * Forcefully reclaim buffers if the driver did not 1597 * correctly return them to vb2. 1598 */ 1599 for (i = 0; i < q->num_buffers; ++i) { 1600 vb = q->bufs[i]; 1601 if (vb->state == VB2_BUF_STATE_ACTIVE) 1602 vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED); 1603 } 1604 /* Must be zero now */ 1605 WARN_ON(atomic_read(&q->owned_by_drv_count)); 1606 } 1607 /* 1608 * If done_list is not empty, then start_streaming() didn't call 1609 * vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED) but STATE_ERROR or 1610 * STATE_DONE. 1611 */ 1612 WARN_ON(!list_empty(&q->done_list)); 1613 return ret; 1614 } 1615 1616 int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb, 1617 struct media_request *req) 1618 { 1619 struct vb2_buffer *vb; 1620 enum vb2_buffer_state orig_state; 1621 int ret; 1622 1623 if (q->error) { 1624 dprintk(q, 1, "fatal error occurred on queue\n"); 1625 return -EIO; 1626 } 1627 1628 vb = q->bufs[index]; 1629 1630 if (!req && vb->state != VB2_BUF_STATE_IN_REQUEST && 1631 q->requires_requests) { 1632 dprintk(q, 1, "qbuf requires a request\n"); 1633 return -EBADR; 1634 } 1635 1636 if ((req && q->uses_qbuf) || 1637 (!req && vb->state != VB2_BUF_STATE_IN_REQUEST && 1638 q->uses_requests)) { 1639 dprintk(q, 1, "queue in wrong mode (qbuf vs requests)\n"); 1640 return -EBUSY; 1641 } 1642 1643 if (req) { 1644 int ret; 1645 1646 q->uses_requests = 1; 1647 if (vb->state != VB2_BUF_STATE_DEQUEUED) { 1648 dprintk(q, 1, "buffer %d not in dequeued state\n", 1649 vb->index); 1650 return -EINVAL; 1651 } 1652 1653 if (q->is_output && !vb->prepared) { 1654 ret = call_vb_qop(vb, buf_out_validate, vb); 1655 if (ret) { 1656 dprintk(q, 1, "buffer validation failed\n"); 1657 return ret; 1658 } 1659 } 1660 1661 media_request_object_init(&vb->req_obj); 1662 1663 /* Make sure the request is in a safe state for updating. */ 1664 ret = media_request_lock_for_update(req); 1665 if (ret) 1666 return ret; 1667 ret = media_request_object_bind(req, &vb2_core_req_ops, 1668 q, true, &vb->req_obj); 1669 media_request_unlock_for_update(req); 1670 if (ret) 1671 return ret; 1672 1673 vb->state = VB2_BUF_STATE_IN_REQUEST; 1674 1675 /* 1676 * Increment the refcount and store the request. 1677 * The request refcount is decremented again when the 1678 * buffer is dequeued. This is to prevent vb2_buffer_done() 1679 * from freeing the request from interrupt context, which can 1680 * happen if the application closed the request fd after 1681 * queueing the request. 1682 */ 1683 media_request_get(req); 1684 vb->request = req; 1685 1686 /* Fill buffer information for the userspace */ 1687 if (pb) { 1688 call_void_bufop(q, copy_timestamp, vb, pb); 1689 call_void_bufop(q, fill_user_buffer, vb, pb); 1690 } 1691 1692 dprintk(q, 2, "qbuf of buffer %d succeeded\n", vb->index); 1693 return 0; 1694 } 1695 1696 if (vb->state != VB2_BUF_STATE_IN_REQUEST) 1697 q->uses_qbuf = 1; 1698 1699 switch (vb->state) { 1700 case VB2_BUF_STATE_DEQUEUED: 1701 case VB2_BUF_STATE_IN_REQUEST: 1702 if (!vb->prepared) { 1703 ret = __buf_prepare(vb); 1704 if (ret) 1705 return ret; 1706 } 1707 break; 1708 case VB2_BUF_STATE_PREPARING: 1709 dprintk(q, 1, "buffer still being prepared\n"); 1710 return -EINVAL; 1711 default: 1712 dprintk(q, 1, "invalid buffer state %s\n", 1713 vb2_state_name(vb->state)); 1714 return -EINVAL; 1715 } 1716 1717 /* 1718 * Add to the queued buffers list, a buffer will stay on it until 1719 * dequeued in dqbuf. 1720 */ 1721 orig_state = vb->state; 1722 list_add_tail(&vb->queued_entry, &q->queued_list); 1723 q->queued_count++; 1724 q->waiting_for_buffers = false; 1725 vb->state = VB2_BUF_STATE_QUEUED; 1726 1727 if (pb) 1728 call_void_bufop(q, copy_timestamp, vb, pb); 1729 1730 trace_vb2_qbuf(q, vb); 1731 1732 /* 1733 * If already streaming, give the buffer to driver for processing. 1734 * If not, the buffer will be given to driver on next streamon. 1735 */ 1736 if (q->start_streaming_called) 1737 __enqueue_in_driver(vb); 1738 1739 /* Fill buffer information for the userspace */ 1740 if (pb) 1741 call_void_bufop(q, fill_user_buffer, vb, pb); 1742 1743 /* 1744 * If streamon has been called, and we haven't yet called 1745 * start_streaming() since not enough buffers were queued, and 1746 * we now have reached the minimum number of queued buffers, 1747 * then we can finally call start_streaming(). 1748 */ 1749 if (q->streaming && !q->start_streaming_called && 1750 q->queued_count >= q->min_buffers_needed) { 1751 ret = vb2_start_streaming(q); 1752 if (ret) { 1753 /* 1754 * Since vb2_core_qbuf will return with an error, 1755 * we should return it to state DEQUEUED since 1756 * the error indicates that the buffer wasn't queued. 1757 */ 1758 list_del(&vb->queued_entry); 1759 q->queued_count--; 1760 vb->state = orig_state; 1761 return ret; 1762 } 1763 } 1764 1765 dprintk(q, 2, "qbuf of buffer %d succeeded\n", vb->index); 1766 return 0; 1767 } 1768 EXPORT_SYMBOL_GPL(vb2_core_qbuf); 1769 1770 /* 1771 * __vb2_wait_for_done_vb() - wait for a buffer to become available 1772 * for dequeuing 1773 * 1774 * Will sleep if required for nonblocking == false. 1775 */ 1776 static int __vb2_wait_for_done_vb(struct vb2_queue *q, int nonblocking) 1777 { 1778 /* 1779 * All operations on vb_done_list are performed under done_lock 1780 * spinlock protection. However, buffers may be removed from 1781 * it and returned to userspace only while holding both driver's 1782 * lock and the done_lock spinlock. Thus we can be sure that as 1783 * long as we hold the driver's lock, the list will remain not 1784 * empty if list_empty() check succeeds. 1785 */ 1786 1787 for (;;) { 1788 int ret; 1789 1790 if (q->waiting_in_dqbuf) { 1791 dprintk(q, 1, "another dup()ped fd is waiting for a buffer\n"); 1792 return -EBUSY; 1793 } 1794 1795 if (!q->streaming) { 1796 dprintk(q, 1, "streaming off, will not wait for buffers\n"); 1797 return -EINVAL; 1798 } 1799 1800 if (q->error) { 1801 dprintk(q, 1, "Queue in error state, will not wait for buffers\n"); 1802 return -EIO; 1803 } 1804 1805 if (q->last_buffer_dequeued) { 1806 dprintk(q, 3, "last buffer dequeued already, will not wait for buffers\n"); 1807 return -EPIPE; 1808 } 1809 1810 if (!list_empty(&q->done_list)) { 1811 /* 1812 * Found a buffer that we were waiting for. 1813 */ 1814 break; 1815 } 1816 1817 if (nonblocking) { 1818 dprintk(q, 3, "nonblocking and no buffers to dequeue, will not wait\n"); 1819 return -EAGAIN; 1820 } 1821 1822 q->waiting_in_dqbuf = 1; 1823 /* 1824 * We are streaming and blocking, wait for another buffer to 1825 * become ready or for streamoff. Driver's lock is released to 1826 * allow streamoff or qbuf to be called while waiting. 1827 */ 1828 call_void_qop(q, wait_prepare, q); 1829 1830 /* 1831 * All locks have been released, it is safe to sleep now. 1832 */ 1833 dprintk(q, 3, "will sleep waiting for buffers\n"); 1834 ret = wait_event_interruptible(q->done_wq, 1835 !list_empty(&q->done_list) || !q->streaming || 1836 q->error); 1837 1838 /* 1839 * We need to reevaluate both conditions again after reacquiring 1840 * the locks or return an error if one occurred. 1841 */ 1842 call_void_qop(q, wait_finish, q); 1843 q->waiting_in_dqbuf = 0; 1844 if (ret) { 1845 dprintk(q, 1, "sleep was interrupted\n"); 1846 return ret; 1847 } 1848 } 1849 return 0; 1850 } 1851 1852 /* 1853 * __vb2_get_done_vb() - get a buffer ready for dequeuing 1854 * 1855 * Will sleep if required for nonblocking == false. 1856 */ 1857 static int __vb2_get_done_vb(struct vb2_queue *q, struct vb2_buffer **vb, 1858 void *pb, int nonblocking) 1859 { 1860 unsigned long flags; 1861 int ret = 0; 1862 1863 /* 1864 * Wait for at least one buffer to become available on the done_list. 1865 */ 1866 ret = __vb2_wait_for_done_vb(q, nonblocking); 1867 if (ret) 1868 return ret; 1869 1870 /* 1871 * Driver's lock has been held since we last verified that done_list 1872 * is not empty, so no need for another list_empty(done_list) check. 1873 */ 1874 spin_lock_irqsave(&q->done_lock, flags); 1875 *vb = list_first_entry(&q->done_list, struct vb2_buffer, done_entry); 1876 /* 1877 * Only remove the buffer from done_list if all planes can be 1878 * handled. Some cases such as V4L2 file I/O and DVB have pb 1879 * == NULL; skip the check then as there's nothing to verify. 1880 */ 1881 if (pb) 1882 ret = call_bufop(q, verify_planes_array, *vb, pb); 1883 if (!ret) 1884 list_del(&(*vb)->done_entry); 1885 spin_unlock_irqrestore(&q->done_lock, flags); 1886 1887 return ret; 1888 } 1889 1890 int vb2_wait_for_all_buffers(struct vb2_queue *q) 1891 { 1892 if (!q->streaming) { 1893 dprintk(q, 1, "streaming off, will not wait for buffers\n"); 1894 return -EINVAL; 1895 } 1896 1897 if (q->start_streaming_called) 1898 wait_event(q->done_wq, !atomic_read(&q->owned_by_drv_count)); 1899 return 0; 1900 } 1901 EXPORT_SYMBOL_GPL(vb2_wait_for_all_buffers); 1902 1903 /* 1904 * __vb2_dqbuf() - bring back the buffer to the DEQUEUED state 1905 */ 1906 static void __vb2_dqbuf(struct vb2_buffer *vb) 1907 { 1908 struct vb2_queue *q = vb->vb2_queue; 1909 1910 /* nothing to do if the buffer is already dequeued */ 1911 if (vb->state == VB2_BUF_STATE_DEQUEUED) 1912 return; 1913 1914 vb->state = VB2_BUF_STATE_DEQUEUED; 1915 1916 call_void_bufop(q, init_buffer, vb); 1917 } 1918 1919 int vb2_core_dqbuf(struct vb2_queue *q, unsigned int *pindex, void *pb, 1920 bool nonblocking) 1921 { 1922 struct vb2_buffer *vb = NULL; 1923 int ret; 1924 1925 ret = __vb2_get_done_vb(q, &vb, pb, nonblocking); 1926 if (ret < 0) 1927 return ret; 1928 1929 switch (vb->state) { 1930 case VB2_BUF_STATE_DONE: 1931 dprintk(q, 3, "returning done buffer\n"); 1932 break; 1933 case VB2_BUF_STATE_ERROR: 1934 dprintk(q, 3, "returning done buffer with errors\n"); 1935 break; 1936 default: 1937 dprintk(q, 1, "invalid buffer state %s\n", 1938 vb2_state_name(vb->state)); 1939 return -EINVAL; 1940 } 1941 1942 call_void_vb_qop(vb, buf_finish, vb); 1943 vb->prepared = 0; 1944 1945 if (pindex) 1946 *pindex = vb->index; 1947 1948 /* Fill buffer information for the userspace */ 1949 if (pb) 1950 call_void_bufop(q, fill_user_buffer, vb, pb); 1951 1952 /* Remove from videobuf queue */ 1953 list_del(&vb->queued_entry); 1954 q->queued_count--; 1955 1956 trace_vb2_dqbuf(q, vb); 1957 1958 /* go back to dequeued state */ 1959 __vb2_dqbuf(vb); 1960 1961 if (WARN_ON(vb->req_obj.req)) { 1962 media_request_object_unbind(&vb->req_obj); 1963 media_request_object_put(&vb->req_obj); 1964 } 1965 if (vb->request) 1966 media_request_put(vb->request); 1967 vb->request = NULL; 1968 1969 dprintk(q, 2, "dqbuf of buffer %d, state: %s\n", 1970 vb->index, vb2_state_name(vb->state)); 1971 1972 return 0; 1973 1974 } 1975 EXPORT_SYMBOL_GPL(vb2_core_dqbuf); 1976 1977 /* 1978 * __vb2_queue_cancel() - cancel and stop (pause) streaming 1979 * 1980 * Removes all queued buffers from driver's queue and all buffers queued by 1981 * userspace from videobuf's queue. Returns to state after reqbufs. 1982 */ 1983 static void __vb2_queue_cancel(struct vb2_queue *q) 1984 { 1985 unsigned int i; 1986 1987 /* 1988 * Tell driver to stop all transactions and release all queued 1989 * buffers. 1990 */ 1991 if (q->start_streaming_called) 1992 call_void_qop(q, stop_streaming, q); 1993 1994 /* 1995 * If you see this warning, then the driver isn't cleaning up properly 1996 * in stop_streaming(). See the stop_streaming() documentation in 1997 * videobuf2-core.h for more information how buffers should be returned 1998 * to vb2 in stop_streaming(). 1999 */ 2000 if (WARN_ON(atomic_read(&q->owned_by_drv_count))) { 2001 for (i = 0; i < q->num_buffers; ++i) 2002 if (q->bufs[i]->state == VB2_BUF_STATE_ACTIVE) { 2003 pr_warn("driver bug: stop_streaming operation is leaving buf %p in active state\n", 2004 q->bufs[i]); 2005 vb2_buffer_done(q->bufs[i], VB2_BUF_STATE_ERROR); 2006 } 2007 /* Must be zero now */ 2008 WARN_ON(atomic_read(&q->owned_by_drv_count)); 2009 } 2010 2011 q->streaming = 0; 2012 q->start_streaming_called = 0; 2013 q->queued_count = 0; 2014 q->error = 0; 2015 q->uses_requests = 0; 2016 q->uses_qbuf = 0; 2017 2018 /* 2019 * Remove all buffers from videobuf's list... 2020 */ 2021 INIT_LIST_HEAD(&q->queued_list); 2022 /* 2023 * ...and done list; userspace will not receive any buffers it 2024 * has not already dequeued before initiating cancel. 2025 */ 2026 INIT_LIST_HEAD(&q->done_list); 2027 atomic_set(&q->owned_by_drv_count, 0); 2028 wake_up_all(&q->done_wq); 2029 2030 /* 2031 * Reinitialize all buffers for next use. 2032 * Make sure to call buf_finish for any queued buffers. Normally 2033 * that's done in dqbuf, but that's not going to happen when we 2034 * cancel the whole queue. Note: this code belongs here, not in 2035 * __vb2_dqbuf() since in vb2_core_dqbuf() there is a critical 2036 * call to __fill_user_buffer() after buf_finish(). That order can't 2037 * be changed, so we can't move the buf_finish() to __vb2_dqbuf(). 2038 */ 2039 for (i = 0; i < q->num_buffers; ++i) { 2040 struct vb2_buffer *vb = q->bufs[i]; 2041 struct media_request *req = vb->req_obj.req; 2042 2043 /* 2044 * If a request is associated with this buffer, then 2045 * call buf_request_cancel() to give the driver to complete() 2046 * related request objects. Otherwise those objects would 2047 * never complete. 2048 */ 2049 if (req) { 2050 enum media_request_state state; 2051 unsigned long flags; 2052 2053 spin_lock_irqsave(&req->lock, flags); 2054 state = req->state; 2055 spin_unlock_irqrestore(&req->lock, flags); 2056 2057 if (state == MEDIA_REQUEST_STATE_QUEUED) 2058 call_void_vb_qop(vb, buf_request_complete, vb); 2059 } 2060 2061 __vb2_buf_mem_finish(vb); 2062 2063 if (vb->prepared) { 2064 call_void_vb_qop(vb, buf_finish, vb); 2065 vb->prepared = 0; 2066 } 2067 __vb2_dqbuf(vb); 2068 2069 if (vb->req_obj.req) { 2070 media_request_object_unbind(&vb->req_obj); 2071 media_request_object_put(&vb->req_obj); 2072 } 2073 if (vb->request) 2074 media_request_put(vb->request); 2075 vb->request = NULL; 2076 vb->copied_timestamp = 0; 2077 } 2078 } 2079 2080 int vb2_core_streamon(struct vb2_queue *q, unsigned int type) 2081 { 2082 int ret; 2083 2084 if (type != q->type) { 2085 dprintk(q, 1, "invalid stream type\n"); 2086 return -EINVAL; 2087 } 2088 2089 if (q->streaming) { 2090 dprintk(q, 3, "already streaming\n"); 2091 return 0; 2092 } 2093 2094 if (!q->num_buffers) { 2095 dprintk(q, 1, "no buffers have been allocated\n"); 2096 return -EINVAL; 2097 } 2098 2099 if (q->num_buffers < q->min_buffers_needed) { 2100 dprintk(q, 1, "need at least %u allocated buffers\n", 2101 q->min_buffers_needed); 2102 return -EINVAL; 2103 } 2104 2105 /* 2106 * Tell driver to start streaming provided sufficient buffers 2107 * are available. 2108 */ 2109 if (q->queued_count >= q->min_buffers_needed) { 2110 ret = v4l_vb2q_enable_media_source(q); 2111 if (ret) 2112 return ret; 2113 ret = vb2_start_streaming(q); 2114 if (ret) 2115 return ret; 2116 } 2117 2118 q->streaming = 1; 2119 2120 dprintk(q, 3, "successful\n"); 2121 return 0; 2122 } 2123 EXPORT_SYMBOL_GPL(vb2_core_streamon); 2124 2125 void vb2_queue_error(struct vb2_queue *q) 2126 { 2127 q->error = 1; 2128 2129 wake_up_all(&q->done_wq); 2130 } 2131 EXPORT_SYMBOL_GPL(vb2_queue_error); 2132 2133 int vb2_core_streamoff(struct vb2_queue *q, unsigned int type) 2134 { 2135 if (type != q->type) { 2136 dprintk(q, 1, "invalid stream type\n"); 2137 return -EINVAL; 2138 } 2139 2140 /* 2141 * Cancel will pause streaming and remove all buffers from the driver 2142 * and videobuf, effectively returning control over them to userspace. 2143 * 2144 * Note that we do this even if q->streaming == 0: if you prepare or 2145 * queue buffers, and then call streamoff without ever having called 2146 * streamon, you would still expect those buffers to be returned to 2147 * their normal dequeued state. 2148 */ 2149 __vb2_queue_cancel(q); 2150 q->waiting_for_buffers = !q->is_output; 2151 q->last_buffer_dequeued = false; 2152 2153 dprintk(q, 3, "successful\n"); 2154 return 0; 2155 } 2156 EXPORT_SYMBOL_GPL(vb2_core_streamoff); 2157 2158 /* 2159 * __find_plane_by_offset() - find plane associated with the given offset off 2160 */ 2161 static int __find_plane_by_offset(struct vb2_queue *q, unsigned long off, 2162 unsigned int *_buffer, unsigned int *_plane) 2163 { 2164 struct vb2_buffer *vb; 2165 unsigned int buffer, plane; 2166 2167 /* 2168 * Go over all buffers and their planes, comparing the given offset 2169 * with an offset assigned to each plane. If a match is found, 2170 * return its buffer and plane numbers. 2171 */ 2172 for (buffer = 0; buffer < q->num_buffers; ++buffer) { 2173 vb = q->bufs[buffer]; 2174 2175 for (plane = 0; plane < vb->num_planes; ++plane) { 2176 if (vb->planes[plane].m.offset == off) { 2177 *_buffer = buffer; 2178 *_plane = plane; 2179 return 0; 2180 } 2181 } 2182 } 2183 2184 return -EINVAL; 2185 } 2186 2187 int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type, 2188 unsigned int index, unsigned int plane, unsigned int flags) 2189 { 2190 struct vb2_buffer *vb = NULL; 2191 struct vb2_plane *vb_plane; 2192 int ret; 2193 struct dma_buf *dbuf; 2194 2195 if (q->memory != VB2_MEMORY_MMAP) { 2196 dprintk(q, 1, "queue is not currently set up for mmap\n"); 2197 return -EINVAL; 2198 } 2199 2200 if (!q->mem_ops->get_dmabuf) { 2201 dprintk(q, 1, "queue does not support DMA buffer exporting\n"); 2202 return -EINVAL; 2203 } 2204 2205 if (flags & ~(O_CLOEXEC | O_ACCMODE)) { 2206 dprintk(q, 1, "queue does support only O_CLOEXEC and access mode flags\n"); 2207 return -EINVAL; 2208 } 2209 2210 if (type != q->type) { 2211 dprintk(q, 1, "invalid buffer type\n"); 2212 return -EINVAL; 2213 } 2214 2215 if (index >= q->num_buffers) { 2216 dprintk(q, 1, "buffer index out of range\n"); 2217 return -EINVAL; 2218 } 2219 2220 vb = q->bufs[index]; 2221 2222 if (plane >= vb->num_planes) { 2223 dprintk(q, 1, "buffer plane out of range\n"); 2224 return -EINVAL; 2225 } 2226 2227 if (vb2_fileio_is_active(q)) { 2228 dprintk(q, 1, "expbuf: file io in progress\n"); 2229 return -EBUSY; 2230 } 2231 2232 vb_plane = &vb->planes[plane]; 2233 2234 dbuf = call_ptr_memop(get_dmabuf, 2235 vb, 2236 vb_plane->mem_priv, 2237 flags & O_ACCMODE); 2238 if (IS_ERR_OR_NULL(dbuf)) { 2239 dprintk(q, 1, "failed to export buffer %d, plane %d\n", 2240 index, plane); 2241 return -EINVAL; 2242 } 2243 2244 ret = dma_buf_fd(dbuf, flags & ~O_ACCMODE); 2245 if (ret < 0) { 2246 dprintk(q, 3, "buffer %d, plane %d failed to export (%d)\n", 2247 index, plane, ret); 2248 dma_buf_put(dbuf); 2249 return ret; 2250 } 2251 2252 dprintk(q, 3, "buffer %d, plane %d exported as %d descriptor\n", 2253 index, plane, ret); 2254 *fd = ret; 2255 2256 return 0; 2257 } 2258 EXPORT_SYMBOL_GPL(vb2_core_expbuf); 2259 2260 int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma) 2261 { 2262 unsigned long off = vma->vm_pgoff << PAGE_SHIFT; 2263 struct vb2_buffer *vb; 2264 unsigned int buffer = 0, plane = 0; 2265 int ret; 2266 unsigned long length; 2267 2268 if (q->memory != VB2_MEMORY_MMAP) { 2269 dprintk(q, 1, "queue is not currently set up for mmap\n"); 2270 return -EINVAL; 2271 } 2272 2273 /* 2274 * Check memory area access mode. 2275 */ 2276 if (!(vma->vm_flags & VM_SHARED)) { 2277 dprintk(q, 1, "invalid vma flags, VM_SHARED needed\n"); 2278 return -EINVAL; 2279 } 2280 if (q->is_output) { 2281 if (!(vma->vm_flags & VM_WRITE)) { 2282 dprintk(q, 1, "invalid vma flags, VM_WRITE needed\n"); 2283 return -EINVAL; 2284 } 2285 } else { 2286 if (!(vma->vm_flags & VM_READ)) { 2287 dprintk(q, 1, "invalid vma flags, VM_READ needed\n"); 2288 return -EINVAL; 2289 } 2290 } 2291 2292 mutex_lock(&q->mmap_lock); 2293 2294 if (vb2_fileio_is_active(q)) { 2295 dprintk(q, 1, "mmap: file io in progress\n"); 2296 ret = -EBUSY; 2297 goto unlock; 2298 } 2299 2300 /* 2301 * Find the plane corresponding to the offset passed by userspace. 2302 */ 2303 ret = __find_plane_by_offset(q, off, &buffer, &plane); 2304 if (ret) 2305 goto unlock; 2306 2307 vb = q->bufs[buffer]; 2308 2309 /* 2310 * MMAP requires page_aligned buffers. 2311 * The buffer length was page_aligned at __vb2_buf_mem_alloc(), 2312 * so, we need to do the same here. 2313 */ 2314 length = PAGE_ALIGN(vb->planes[plane].length); 2315 if (length < (vma->vm_end - vma->vm_start)) { 2316 dprintk(q, 1, 2317 "MMAP invalid, as it would overflow buffer length\n"); 2318 ret = -EINVAL; 2319 goto unlock; 2320 } 2321 2322 /* 2323 * vm_pgoff is treated in V4L2 API as a 'cookie' to select a buffer, 2324 * not as a in-buffer offset. We always want to mmap a whole buffer 2325 * from its beginning. 2326 */ 2327 vma->vm_pgoff = 0; 2328 2329 ret = call_memop(vb, mmap, vb->planes[plane].mem_priv, vma); 2330 2331 unlock: 2332 mutex_unlock(&q->mmap_lock); 2333 if (ret) 2334 return ret; 2335 2336 dprintk(q, 3, "buffer %d, plane %d successfully mapped\n", buffer, plane); 2337 return 0; 2338 } 2339 EXPORT_SYMBOL_GPL(vb2_mmap); 2340 2341 #ifndef CONFIG_MMU 2342 unsigned long vb2_get_unmapped_area(struct vb2_queue *q, 2343 unsigned long addr, 2344 unsigned long len, 2345 unsigned long pgoff, 2346 unsigned long flags) 2347 { 2348 unsigned long off = pgoff << PAGE_SHIFT; 2349 struct vb2_buffer *vb; 2350 unsigned int buffer, plane; 2351 void *vaddr; 2352 int ret; 2353 2354 if (q->memory != VB2_MEMORY_MMAP) { 2355 dprintk(q, 1, "queue is not currently set up for mmap\n"); 2356 return -EINVAL; 2357 } 2358 2359 /* 2360 * Find the plane corresponding to the offset passed by userspace. 2361 */ 2362 ret = __find_plane_by_offset(q, off, &buffer, &plane); 2363 if (ret) 2364 return ret; 2365 2366 vb = q->bufs[buffer]; 2367 2368 vaddr = vb2_plane_vaddr(vb, plane); 2369 return vaddr ? (unsigned long)vaddr : -EINVAL; 2370 } 2371 EXPORT_SYMBOL_GPL(vb2_get_unmapped_area); 2372 #endif 2373 2374 int vb2_core_queue_init(struct vb2_queue *q) 2375 { 2376 /* 2377 * Sanity check 2378 */ 2379 if (WARN_ON(!q) || 2380 WARN_ON(!q->ops) || 2381 WARN_ON(!q->mem_ops) || 2382 WARN_ON(!q->type) || 2383 WARN_ON(!q->io_modes) || 2384 WARN_ON(!q->ops->queue_setup) || 2385 WARN_ON(!q->ops->buf_queue)) 2386 return -EINVAL; 2387 2388 if (WARN_ON(q->requires_requests && !q->supports_requests)) 2389 return -EINVAL; 2390 2391 /* 2392 * This combination is not allowed since a non-zero value of 2393 * q->min_buffers_needed can cause vb2_core_qbuf() to fail if 2394 * it has to call start_streaming(), and the Request API expects 2395 * that queueing a request (and thus queueing a buffer contained 2396 * in that request) will always succeed. There is no method of 2397 * propagating an error back to userspace. 2398 */ 2399 if (WARN_ON(q->supports_requests && q->min_buffers_needed)) 2400 return -EINVAL; 2401 2402 INIT_LIST_HEAD(&q->queued_list); 2403 INIT_LIST_HEAD(&q->done_list); 2404 spin_lock_init(&q->done_lock); 2405 mutex_init(&q->mmap_lock); 2406 init_waitqueue_head(&q->done_wq); 2407 2408 q->memory = VB2_MEMORY_UNKNOWN; 2409 2410 if (q->buf_struct_size == 0) 2411 q->buf_struct_size = sizeof(struct vb2_buffer); 2412 2413 if (q->bidirectional) 2414 q->dma_dir = DMA_BIDIRECTIONAL; 2415 else 2416 q->dma_dir = q->is_output ? DMA_TO_DEVICE : DMA_FROM_DEVICE; 2417 2418 if (q->name[0] == '\0') 2419 snprintf(q->name, sizeof(q->name), "%s-%p", 2420 q->is_output ? "out" : "cap", q); 2421 2422 return 0; 2423 } 2424 EXPORT_SYMBOL_GPL(vb2_core_queue_init); 2425 2426 static int __vb2_init_fileio(struct vb2_queue *q, int read); 2427 static int __vb2_cleanup_fileio(struct vb2_queue *q); 2428 void vb2_core_queue_release(struct vb2_queue *q) 2429 { 2430 __vb2_cleanup_fileio(q); 2431 __vb2_queue_cancel(q); 2432 mutex_lock(&q->mmap_lock); 2433 __vb2_queue_free(q, q->num_buffers); 2434 mutex_unlock(&q->mmap_lock); 2435 } 2436 EXPORT_SYMBOL_GPL(vb2_core_queue_release); 2437 2438 __poll_t vb2_core_poll(struct vb2_queue *q, struct file *file, 2439 poll_table *wait) 2440 { 2441 __poll_t req_events = poll_requested_events(wait); 2442 struct vb2_buffer *vb = NULL; 2443 unsigned long flags; 2444 2445 /* 2446 * poll_wait() MUST be called on the first invocation on all the 2447 * potential queues of interest, even if we are not interested in their 2448 * events during this first call. Failure to do so will result in 2449 * queue's events to be ignored because the poll_table won't be capable 2450 * of adding new wait queues thereafter. 2451 */ 2452 poll_wait(file, &q->done_wq, wait); 2453 2454 if (!q->is_output && !(req_events & (EPOLLIN | EPOLLRDNORM))) 2455 return 0; 2456 if (q->is_output && !(req_events & (EPOLLOUT | EPOLLWRNORM))) 2457 return 0; 2458 2459 /* 2460 * Start file I/O emulator only if streaming API has not been used yet. 2461 */ 2462 if (q->num_buffers == 0 && !vb2_fileio_is_active(q)) { 2463 if (!q->is_output && (q->io_modes & VB2_READ) && 2464 (req_events & (EPOLLIN | EPOLLRDNORM))) { 2465 if (__vb2_init_fileio(q, 1)) 2466 return EPOLLERR; 2467 } 2468 if (q->is_output && (q->io_modes & VB2_WRITE) && 2469 (req_events & (EPOLLOUT | EPOLLWRNORM))) { 2470 if (__vb2_init_fileio(q, 0)) 2471 return EPOLLERR; 2472 /* 2473 * Write to OUTPUT queue can be done immediately. 2474 */ 2475 return EPOLLOUT | EPOLLWRNORM; 2476 } 2477 } 2478 2479 /* 2480 * There is nothing to wait for if the queue isn't streaming, or if the 2481 * error flag is set. 2482 */ 2483 if (!vb2_is_streaming(q) || q->error) 2484 return EPOLLERR; 2485 2486 /* 2487 * If this quirk is set and QBUF hasn't been called yet then 2488 * return EPOLLERR as well. This only affects capture queues, output 2489 * queues will always initialize waiting_for_buffers to false. 2490 * This quirk is set by V4L2 for backwards compatibility reasons. 2491 */ 2492 if (q->quirk_poll_must_check_waiting_for_buffers && 2493 q->waiting_for_buffers && (req_events & (EPOLLIN | EPOLLRDNORM))) 2494 return EPOLLERR; 2495 2496 /* 2497 * For output streams you can call write() as long as there are fewer 2498 * buffers queued than there are buffers available. 2499 */ 2500 if (q->is_output && q->fileio && q->queued_count < q->num_buffers) 2501 return EPOLLOUT | EPOLLWRNORM; 2502 2503 if (list_empty(&q->done_list)) { 2504 /* 2505 * If the last buffer was dequeued from a capture queue, 2506 * return immediately. DQBUF will return -EPIPE. 2507 */ 2508 if (q->last_buffer_dequeued) 2509 return EPOLLIN | EPOLLRDNORM; 2510 } 2511 2512 /* 2513 * Take first buffer available for dequeuing. 2514 */ 2515 spin_lock_irqsave(&q->done_lock, flags); 2516 if (!list_empty(&q->done_list)) 2517 vb = list_first_entry(&q->done_list, struct vb2_buffer, 2518 done_entry); 2519 spin_unlock_irqrestore(&q->done_lock, flags); 2520 2521 if (vb && (vb->state == VB2_BUF_STATE_DONE 2522 || vb->state == VB2_BUF_STATE_ERROR)) { 2523 return (q->is_output) ? 2524 EPOLLOUT | EPOLLWRNORM : 2525 EPOLLIN | EPOLLRDNORM; 2526 } 2527 return 0; 2528 } 2529 EXPORT_SYMBOL_GPL(vb2_core_poll); 2530 2531 /* 2532 * struct vb2_fileio_buf - buffer context used by file io emulator 2533 * 2534 * vb2 provides a compatibility layer and emulator of file io (read and 2535 * write) calls on top of streaming API. This structure is used for 2536 * tracking context related to the buffers. 2537 */ 2538 struct vb2_fileio_buf { 2539 void *vaddr; 2540 unsigned int size; 2541 unsigned int pos; 2542 unsigned int queued:1; 2543 }; 2544 2545 /* 2546 * struct vb2_fileio_data - queue context used by file io emulator 2547 * 2548 * @cur_index: the index of the buffer currently being read from or 2549 * written to. If equal to q->num_buffers then a new buffer 2550 * must be dequeued. 2551 * @initial_index: in the read() case all buffers are queued up immediately 2552 * in __vb2_init_fileio() and __vb2_perform_fileio() just cycles 2553 * buffers. However, in the write() case no buffers are initially 2554 * queued, instead whenever a buffer is full it is queued up by 2555 * __vb2_perform_fileio(). Only once all available buffers have 2556 * been queued up will __vb2_perform_fileio() start to dequeue 2557 * buffers. This means that initially __vb2_perform_fileio() 2558 * needs to know what buffer index to use when it is queuing up 2559 * the buffers for the first time. That initial index is stored 2560 * in this field. Once it is equal to q->num_buffers all 2561 * available buffers have been queued and __vb2_perform_fileio() 2562 * should start the normal dequeue/queue cycle. 2563 * 2564 * vb2 provides a compatibility layer and emulator of file io (read and 2565 * write) calls on top of streaming API. For proper operation it required 2566 * this structure to save the driver state between each call of the read 2567 * or write function. 2568 */ 2569 struct vb2_fileio_data { 2570 unsigned int count; 2571 unsigned int type; 2572 unsigned int memory; 2573 struct vb2_fileio_buf bufs[VB2_MAX_FRAME]; 2574 unsigned int cur_index; 2575 unsigned int initial_index; 2576 unsigned int q_count; 2577 unsigned int dq_count; 2578 unsigned read_once:1; 2579 unsigned write_immediately:1; 2580 }; 2581 2582 /* 2583 * __vb2_init_fileio() - initialize file io emulator 2584 * @q: videobuf2 queue 2585 * @read: mode selector (1 means read, 0 means write) 2586 */ 2587 static int __vb2_init_fileio(struct vb2_queue *q, int read) 2588 { 2589 struct vb2_fileio_data *fileio; 2590 int i, ret; 2591 unsigned int count = 0; 2592 2593 /* 2594 * Sanity check 2595 */ 2596 if (WARN_ON((read && !(q->io_modes & VB2_READ)) || 2597 (!read && !(q->io_modes & VB2_WRITE)))) 2598 return -EINVAL; 2599 2600 /* 2601 * Check if device supports mapping buffers to kernel virtual space. 2602 */ 2603 if (!q->mem_ops->vaddr) 2604 return -EBUSY; 2605 2606 /* 2607 * Check if streaming api has not been already activated. 2608 */ 2609 if (q->streaming || q->num_buffers > 0) 2610 return -EBUSY; 2611 2612 /* 2613 * Start with count 1, driver can increase it in queue_setup() 2614 */ 2615 count = 1; 2616 2617 dprintk(q, 3, "setting up file io: mode %s, count %d, read_once %d, write_immediately %d\n", 2618 (read) ? "read" : "write", count, q->fileio_read_once, 2619 q->fileio_write_immediately); 2620 2621 fileio = kzalloc(sizeof(*fileio), GFP_KERNEL); 2622 if (fileio == NULL) 2623 return -ENOMEM; 2624 2625 fileio->read_once = q->fileio_read_once; 2626 fileio->write_immediately = q->fileio_write_immediately; 2627 2628 /* 2629 * Request buffers and use MMAP type to force driver 2630 * to allocate buffers by itself. 2631 */ 2632 fileio->count = count; 2633 fileio->memory = VB2_MEMORY_MMAP; 2634 fileio->type = q->type; 2635 q->fileio = fileio; 2636 ret = vb2_core_reqbufs(q, fileio->memory, 0, &fileio->count); 2637 if (ret) 2638 goto err_kfree; 2639 2640 /* 2641 * Check if plane_count is correct 2642 * (multiplane buffers are not supported). 2643 */ 2644 if (q->bufs[0]->num_planes != 1) { 2645 ret = -EBUSY; 2646 goto err_reqbufs; 2647 } 2648 2649 /* 2650 * Get kernel address of each buffer. 2651 */ 2652 for (i = 0; i < q->num_buffers; i++) { 2653 fileio->bufs[i].vaddr = vb2_plane_vaddr(q->bufs[i], 0); 2654 if (fileio->bufs[i].vaddr == NULL) { 2655 ret = -EINVAL; 2656 goto err_reqbufs; 2657 } 2658 fileio->bufs[i].size = vb2_plane_size(q->bufs[i], 0); 2659 } 2660 2661 /* 2662 * Read mode requires pre queuing of all buffers. 2663 */ 2664 if (read) { 2665 /* 2666 * Queue all buffers. 2667 */ 2668 for (i = 0; i < q->num_buffers; i++) { 2669 ret = vb2_core_qbuf(q, i, NULL, NULL); 2670 if (ret) 2671 goto err_reqbufs; 2672 fileio->bufs[i].queued = 1; 2673 } 2674 /* 2675 * All buffers have been queued, so mark that by setting 2676 * initial_index to q->num_buffers 2677 */ 2678 fileio->initial_index = q->num_buffers; 2679 fileio->cur_index = q->num_buffers; 2680 } 2681 2682 /* 2683 * Start streaming. 2684 */ 2685 ret = vb2_core_streamon(q, q->type); 2686 if (ret) 2687 goto err_reqbufs; 2688 2689 return ret; 2690 2691 err_reqbufs: 2692 fileio->count = 0; 2693 vb2_core_reqbufs(q, fileio->memory, 0, &fileio->count); 2694 2695 err_kfree: 2696 q->fileio = NULL; 2697 kfree(fileio); 2698 return ret; 2699 } 2700 2701 /* 2702 * __vb2_cleanup_fileio() - free resourced used by file io emulator 2703 * @q: videobuf2 queue 2704 */ 2705 static int __vb2_cleanup_fileio(struct vb2_queue *q) 2706 { 2707 struct vb2_fileio_data *fileio = q->fileio; 2708 2709 if (fileio) { 2710 vb2_core_streamoff(q, q->type); 2711 q->fileio = NULL; 2712 fileio->count = 0; 2713 vb2_core_reqbufs(q, fileio->memory, 0, &fileio->count); 2714 kfree(fileio); 2715 dprintk(q, 3, "file io emulator closed\n"); 2716 } 2717 return 0; 2718 } 2719 2720 /* 2721 * __vb2_perform_fileio() - perform a single file io (read or write) operation 2722 * @q: videobuf2 queue 2723 * @data: pointed to target userspace buffer 2724 * @count: number of bytes to read or write 2725 * @ppos: file handle position tracking pointer 2726 * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) 2727 * @read: access mode selector (1 means read, 0 means write) 2728 */ 2729 static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_t count, 2730 loff_t *ppos, int nonblock, int read) 2731 { 2732 struct vb2_fileio_data *fileio; 2733 struct vb2_fileio_buf *buf; 2734 bool is_multiplanar = q->is_multiplanar; 2735 /* 2736 * When using write() to write data to an output video node the vb2 core 2737 * should copy timestamps if V4L2_BUF_FLAG_TIMESTAMP_COPY is set. Nobody 2738 * else is able to provide this information with the write() operation. 2739 */ 2740 bool copy_timestamp = !read && q->copy_timestamp; 2741 unsigned index; 2742 int ret; 2743 2744 dprintk(q, 3, "mode %s, offset %ld, count %zd, %sblocking\n", 2745 read ? "read" : "write", (long)*ppos, count, 2746 nonblock ? "non" : ""); 2747 2748 if (!data) 2749 return -EINVAL; 2750 2751 if (q->waiting_in_dqbuf) { 2752 dprintk(q, 3, "another dup()ped fd is %s\n", 2753 read ? "reading" : "writing"); 2754 return -EBUSY; 2755 } 2756 2757 /* 2758 * Initialize emulator on first call. 2759 */ 2760 if (!vb2_fileio_is_active(q)) { 2761 ret = __vb2_init_fileio(q, read); 2762 dprintk(q, 3, "vb2_init_fileio result: %d\n", ret); 2763 if (ret) 2764 return ret; 2765 } 2766 fileio = q->fileio; 2767 2768 /* 2769 * Check if we need to dequeue the buffer. 2770 */ 2771 index = fileio->cur_index; 2772 if (index >= q->num_buffers) { 2773 struct vb2_buffer *b; 2774 2775 /* 2776 * Call vb2_dqbuf to get buffer back. 2777 */ 2778 ret = vb2_core_dqbuf(q, &index, NULL, nonblock); 2779 dprintk(q, 5, "vb2_dqbuf result: %d\n", ret); 2780 if (ret) 2781 return ret; 2782 fileio->dq_count += 1; 2783 2784 fileio->cur_index = index; 2785 buf = &fileio->bufs[index]; 2786 b = q->bufs[index]; 2787 2788 /* 2789 * Get number of bytes filled by the driver 2790 */ 2791 buf->pos = 0; 2792 buf->queued = 0; 2793 buf->size = read ? vb2_get_plane_payload(q->bufs[index], 0) 2794 : vb2_plane_size(q->bufs[index], 0); 2795 /* Compensate for data_offset on read in the multiplanar case. */ 2796 if (is_multiplanar && read && 2797 b->planes[0].data_offset < buf->size) { 2798 buf->pos = b->planes[0].data_offset; 2799 buf->size -= buf->pos; 2800 } 2801 } else { 2802 buf = &fileio->bufs[index]; 2803 } 2804 2805 /* 2806 * Limit count on last few bytes of the buffer. 2807 */ 2808 if (buf->pos + count > buf->size) { 2809 count = buf->size - buf->pos; 2810 dprintk(q, 5, "reducing read count: %zd\n", count); 2811 } 2812 2813 /* 2814 * Transfer data to userspace. 2815 */ 2816 dprintk(q, 3, "copying %zd bytes - buffer %d, offset %u\n", 2817 count, index, buf->pos); 2818 if (read) 2819 ret = copy_to_user(data, buf->vaddr + buf->pos, count); 2820 else 2821 ret = copy_from_user(buf->vaddr + buf->pos, data, count); 2822 if (ret) { 2823 dprintk(q, 3, "error copying data\n"); 2824 return -EFAULT; 2825 } 2826 2827 /* 2828 * Update counters. 2829 */ 2830 buf->pos += count; 2831 *ppos += count; 2832 2833 /* 2834 * Queue next buffer if required. 2835 */ 2836 if (buf->pos == buf->size || (!read && fileio->write_immediately)) { 2837 struct vb2_buffer *b = q->bufs[index]; 2838 2839 /* 2840 * Check if this is the last buffer to read. 2841 */ 2842 if (read && fileio->read_once && fileio->dq_count == 1) { 2843 dprintk(q, 3, "read limit reached\n"); 2844 return __vb2_cleanup_fileio(q); 2845 } 2846 2847 /* 2848 * Call vb2_qbuf and give buffer to the driver. 2849 */ 2850 b->planes[0].bytesused = buf->pos; 2851 2852 if (copy_timestamp) 2853 b->timestamp = ktime_get_ns(); 2854 ret = vb2_core_qbuf(q, index, NULL, NULL); 2855 dprintk(q, 5, "vb2_dbuf result: %d\n", ret); 2856 if (ret) 2857 return ret; 2858 2859 /* 2860 * Buffer has been queued, update the status 2861 */ 2862 buf->pos = 0; 2863 buf->queued = 1; 2864 buf->size = vb2_plane_size(q->bufs[index], 0); 2865 fileio->q_count += 1; 2866 /* 2867 * If we are queuing up buffers for the first time, then 2868 * increase initial_index by one. 2869 */ 2870 if (fileio->initial_index < q->num_buffers) 2871 fileio->initial_index++; 2872 /* 2873 * The next buffer to use is either a buffer that's going to be 2874 * queued for the first time (initial_index < q->num_buffers) 2875 * or it is equal to q->num_buffers, meaning that the next 2876 * time we need to dequeue a buffer since we've now queued up 2877 * all the 'first time' buffers. 2878 */ 2879 fileio->cur_index = fileio->initial_index; 2880 } 2881 2882 /* 2883 * Return proper number of bytes processed. 2884 */ 2885 if (ret == 0) 2886 ret = count; 2887 return ret; 2888 } 2889 2890 size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, 2891 loff_t *ppos, int nonblocking) 2892 { 2893 return __vb2_perform_fileio(q, data, count, ppos, nonblocking, 1); 2894 } 2895 EXPORT_SYMBOL_GPL(vb2_read); 2896 2897 size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, 2898 loff_t *ppos, int nonblocking) 2899 { 2900 return __vb2_perform_fileio(q, (char __user *) data, count, 2901 ppos, nonblocking, 0); 2902 } 2903 EXPORT_SYMBOL_GPL(vb2_write); 2904 2905 struct vb2_threadio_data { 2906 struct task_struct *thread; 2907 vb2_thread_fnc fnc; 2908 void *priv; 2909 bool stop; 2910 }; 2911 2912 static int vb2_thread(void *data) 2913 { 2914 struct vb2_queue *q = data; 2915 struct vb2_threadio_data *threadio = q->threadio; 2916 bool copy_timestamp = false; 2917 unsigned prequeue = 0; 2918 unsigned index = 0; 2919 int ret = 0; 2920 2921 if (q->is_output) { 2922 prequeue = q->num_buffers; 2923 copy_timestamp = q->copy_timestamp; 2924 } 2925 2926 set_freezable(); 2927 2928 for (;;) { 2929 struct vb2_buffer *vb; 2930 2931 /* 2932 * Call vb2_dqbuf to get buffer back. 2933 */ 2934 if (prequeue) { 2935 vb = q->bufs[index++]; 2936 prequeue--; 2937 } else { 2938 call_void_qop(q, wait_finish, q); 2939 if (!threadio->stop) 2940 ret = vb2_core_dqbuf(q, &index, NULL, 0); 2941 call_void_qop(q, wait_prepare, q); 2942 dprintk(q, 5, "file io: vb2_dqbuf result: %d\n", ret); 2943 if (!ret) 2944 vb = q->bufs[index]; 2945 } 2946 if (ret || threadio->stop) 2947 break; 2948 try_to_freeze(); 2949 2950 if (vb->state != VB2_BUF_STATE_ERROR) 2951 if (threadio->fnc(vb, threadio->priv)) 2952 break; 2953 call_void_qop(q, wait_finish, q); 2954 if (copy_timestamp) 2955 vb->timestamp = ktime_get_ns(); 2956 if (!threadio->stop) 2957 ret = vb2_core_qbuf(q, vb->index, NULL, NULL); 2958 call_void_qop(q, wait_prepare, q); 2959 if (ret || threadio->stop) 2960 break; 2961 } 2962 2963 /* Hmm, linux becomes *very* unhappy without this ... */ 2964 while (!kthread_should_stop()) { 2965 set_current_state(TASK_INTERRUPTIBLE); 2966 schedule(); 2967 } 2968 return 0; 2969 } 2970 2971 /* 2972 * This function should not be used for anything else but the videobuf2-dvb 2973 * support. If you think you have another good use-case for this, then please 2974 * contact the linux-media mailinglist first. 2975 */ 2976 int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv, 2977 const char *thread_name) 2978 { 2979 struct vb2_threadio_data *threadio; 2980 int ret = 0; 2981 2982 if (q->threadio) 2983 return -EBUSY; 2984 if (vb2_is_busy(q)) 2985 return -EBUSY; 2986 if (WARN_ON(q->fileio)) 2987 return -EBUSY; 2988 2989 threadio = kzalloc(sizeof(*threadio), GFP_KERNEL); 2990 if (threadio == NULL) 2991 return -ENOMEM; 2992 threadio->fnc = fnc; 2993 threadio->priv = priv; 2994 2995 ret = __vb2_init_fileio(q, !q->is_output); 2996 dprintk(q, 3, "file io: vb2_init_fileio result: %d\n", ret); 2997 if (ret) 2998 goto nomem; 2999 q->threadio = threadio; 3000 threadio->thread = kthread_run(vb2_thread, q, "vb2-%s", thread_name); 3001 if (IS_ERR(threadio->thread)) { 3002 ret = PTR_ERR(threadio->thread); 3003 threadio->thread = NULL; 3004 goto nothread; 3005 } 3006 return 0; 3007 3008 nothread: 3009 __vb2_cleanup_fileio(q); 3010 nomem: 3011 kfree(threadio); 3012 return ret; 3013 } 3014 EXPORT_SYMBOL_GPL(vb2_thread_start); 3015 3016 int vb2_thread_stop(struct vb2_queue *q) 3017 { 3018 struct vb2_threadio_data *threadio = q->threadio; 3019 int err; 3020 3021 if (threadio == NULL) 3022 return 0; 3023 threadio->stop = true; 3024 /* Wake up all pending sleeps in the thread */ 3025 vb2_queue_error(q); 3026 err = kthread_stop(threadio->thread); 3027 __vb2_cleanup_fileio(q); 3028 threadio->thread = NULL; 3029 kfree(threadio); 3030 q->threadio = NULL; 3031 return err; 3032 } 3033 EXPORT_SYMBOL_GPL(vb2_thread_stop); 3034 3035 MODULE_DESCRIPTION("Media buffer core framework"); 3036 MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski"); 3037 MODULE_LICENSE("GPL"); 3038 MODULE_IMPORT_NS(DMA_BUF); 3039