drivers/media/common/videobuf2/videobuf2-v4l2.c

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This source file includes following definitions.
__verify_planes_array
__verify_planes_array_core
__verify_length
__init_vb2_v4l2_buffer
__copy_timestamp
vb2_warn_zero_bytesused
vb2_fill_vb2_v4l2_buffer
vb2_queue_or_prepare_buf
__fill_v4l2_buffer
__fill_vb2_buffer
vb2_find_timestamp
vb2_querybuf
fill_buf_caps
vb2_reqbufs
vb2_prepare_buf
vb2_create_bufs
vb2_qbuf
vb2_dqbuf
vb2_streamon
vb2_streamoff
vb2_expbuf
vb2_queue_init
vb2_queue_release
vb2_poll
vb2_queue_is_busy
vb2_ioctl_reqbufs
vb2_ioctl_create_bufs
vb2_ioctl_prepare_buf
vb2_ioctl_querybuf
vb2_ioctl_qbuf
vb2_ioctl_dqbuf
vb2_ioctl_streamon
vb2_ioctl_streamoff
vb2_ioctl_expbuf
vb2_fop_mmap
_vb2_fop_release
vb2_fop_release
vb2_fop_write
vb2_fop_read
vb2_fop_poll
vb2_fop_get_unmapped_area
vb2_ops_wait_prepare
vb2_ops_wait_finish
vb2_request_validate
vb2_request_queue
   1 /*
   2  * videobuf2-v4l2.c - V4L2 driver helper 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 #include <linux/err.h>
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/mm.h>
  21 #include <linux/poll.h>
  22 #include <linux/slab.h>
  23 #include <linux/sched.h>
  24 #include <linux/freezer.h>
  25 #include <linux/kthread.h>
  26 
  27 #include <media/v4l2-dev.h>
  28 #include <media/v4l2-device.h>
  29 #include <media/v4l2-fh.h>
  30 #include <media/v4l2-event.h>
  31 #include <media/v4l2-common.h>
  32 
  33 #include <media/videobuf2-v4l2.h>
  34 
  35 static int debug;
  36 module_param(debug, int, 0644);
  37 
  38 #define dprintk(level, fmt, arg...)                                           \
  39         do {                                                                  \
  40                 if (debug >= level)                                           \
  41                         pr_info("vb2-v4l2: %s: " fmt, __func__, ## arg); \
  42         } while (0)
  43 
  44 /* Flags that are set by us */
  45 #define V4L2_BUFFER_MASK_FLAGS  (V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_QUEUED | \
  46                                  V4L2_BUF_FLAG_DONE | V4L2_BUF_FLAG_ERROR | \
  47                                  V4L2_BUF_FLAG_PREPARED | \
  48                                  V4L2_BUF_FLAG_IN_REQUEST | \
  49                                  V4L2_BUF_FLAG_REQUEST_FD | \
  50                                  V4L2_BUF_FLAG_TIMESTAMP_MASK)
  51 /* Output buffer flags that should be passed on to the driver */
  52 #define V4L2_BUFFER_OUT_FLAGS   (V4L2_BUF_FLAG_PFRAME | V4L2_BUF_FLAG_BFRAME | \
  53                                  V4L2_BUF_FLAG_KEYFRAME | V4L2_BUF_FLAG_TIMECODE)
  54 
  55 /*
  56  * __verify_planes_array() - verify that the planes array passed in struct
  57  * v4l2_buffer from userspace can be safely used
  58  */
  59 static int __verify_planes_array(struct vb2_buffer *vb, const struct v4l2_buffer *b)
  60 {
  61         if (!V4L2_TYPE_IS_MULTIPLANAR(b->type))
  62                 return 0;
  63 
  64         /* Is memory for copying plane information present? */
  65         if (b->m.planes == NULL) {
  66                 dprintk(1, "multi-planar buffer passed but planes array not provided\n");
  67                 return -EINVAL;
  68         }
  69 
  70         if (b->length < vb->num_planes || b->length > VB2_MAX_PLANES) {
  71                 dprintk(1, "incorrect planes array length, expected %d, got %d\n",
  72                         vb->num_planes, b->length);
  73                 return -EINVAL;
  74         }
  75 
  76         return 0;
  77 }
  78 
  79 static int __verify_planes_array_core(struct vb2_buffer *vb, const void *pb)
  80 {
  81         return __verify_planes_array(vb, pb);
  82 }
  83 
  84 /*
  85  * __verify_length() - Verify that the bytesused value for each plane fits in
  86  * the plane length and that the data offset doesn't exceed the bytesused value.
  87  */
  88 static int __verify_length(struct vb2_buffer *vb, const struct v4l2_buffer *b)
  89 {
  90         unsigned int length;
  91         unsigned int bytesused;
  92         unsigned int plane;
  93 
  94         if (!V4L2_TYPE_IS_OUTPUT(b->type))
  95                 return 0;
  96 
  97         if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) {
  98                 for (plane = 0; plane < vb->num_planes; ++plane) {
  99                         length = (b->memory == VB2_MEMORY_USERPTR ||
 100                                   b->memory == VB2_MEMORY_DMABUF)
 101                                ? b->m.planes[plane].length
 102                                 : vb->planes[plane].length;
 103                         bytesused = b->m.planes[plane].bytesused
 104                                   ? b->m.planes[plane].bytesused : length;
 105 
 106                         if (b->m.planes[plane].bytesused > length)
 107                                 return -EINVAL;
 108 
 109                         if (b->m.planes[plane].data_offset > 0 &&
 110                             b->m.planes[plane].data_offset >= bytesused)
 111                                 return -EINVAL;
 112                 }
 113         } else {
 114                 length = (b->memory == VB2_MEMORY_USERPTR)
 115                         ? b->length : vb->planes[0].length;
 116 
 117                 if (b->bytesused > length)
 118                         return -EINVAL;
 119         }
 120 
 121         return 0;
 122 }
 123 
 124 /*
 125  * __init_vb2_v4l2_buffer() - initialize the vb2_v4l2_buffer struct
 126  */
 127 static void __init_vb2_v4l2_buffer(struct vb2_buffer *vb)
 128 {
 129         struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
 130 
 131         vbuf->request_fd = -1;
 132 }
 133 
 134 static void __copy_timestamp(struct vb2_buffer *vb, const void *pb)
 135 {
 136         const struct v4l2_buffer *b = pb;
 137         struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
 138         struct vb2_queue *q = vb->vb2_queue;
 139 
 140         if (q->is_output) {
 141                 /*
 142                  * For output buffers copy the timestamp if needed,
 143                  * and the timecode field and flag if needed.
 144                  */
 145                 if (q->copy_timestamp)
 146                         vb->timestamp = v4l2_timeval_to_ns(&b->timestamp);
 147                 vbuf->flags |= b->flags & V4L2_BUF_FLAG_TIMECODE;
 148                 if (b->flags & V4L2_BUF_FLAG_TIMECODE)
 149                         vbuf->timecode = b->timecode;
 150         }
 151 };
 152 
 153 static void vb2_warn_zero_bytesused(struct vb2_buffer *vb)
 154 {
 155         static bool check_once;
 156 
 157         if (check_once)
 158                 return;
 159 
 160         check_once = true;
 161 
 162         pr_warn("use of bytesused == 0 is deprecated and will be removed in the future,\n");
 163         if (vb->vb2_queue->allow_zero_bytesused)
 164                 pr_warn("use VIDIOC_DECODER_CMD(V4L2_DEC_CMD_STOP) instead.\n");
 165         else
 166                 pr_warn("use the actual size instead.\n");
 167 }
 168 
 169 static int vb2_fill_vb2_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b)
 170 {
 171         struct vb2_queue *q = vb->vb2_queue;
 172         struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
 173         struct vb2_plane *planes = vbuf->planes;
 174         unsigned int plane;
 175         int ret;
 176 
 177         ret = __verify_length(vb, b);
 178         if (ret < 0) {
 179                 dprintk(1, "plane parameters verification failed: %d\n", ret);
 180                 return ret;
 181         }
 182         if (b->field == V4L2_FIELD_ALTERNATE && q->is_output) {
 183                 /*
 184                  * If the format's field is ALTERNATE, then the buffer's field
 185                  * should be either TOP or BOTTOM, not ALTERNATE since that
 186                  * makes no sense. The driver has to know whether the
 187                  * buffer represents a top or a bottom field in order to
 188                  * program any DMA correctly. Using ALTERNATE is wrong, since
 189                  * that just says that it is either a top or a bottom field,
 190                  * but not which of the two it is.
 191                  */
 192                 dprintk(1, "the field is incorrectly set to ALTERNATE for an output buffer\n");
 193                 return -EINVAL;
 194         }
 195         vbuf->sequence = 0;
 196         vbuf->request_fd = -1;
 197 
 198         if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) {
 199                 switch (b->memory) {
 200                 case VB2_MEMORY_USERPTR:
 201                         for (plane = 0; plane < vb->num_planes; ++plane) {
 202                                 planes[plane].m.userptr =
 203                                         b->m.planes[plane].m.userptr;
 204                                 planes[plane].length =
 205                                         b->m.planes[plane].length;
 206                         }
 207                         break;
 208                 case VB2_MEMORY_DMABUF:
 209                         for (plane = 0; plane < vb->num_planes; ++plane) {
 210                                 planes[plane].m.fd =
 211                                         b->m.planes[plane].m.fd;
 212                                 planes[plane].length =
 213                                         b->m.planes[plane].length;
 214                         }
 215                         break;
 216                 default:
 217                         for (plane = 0; plane < vb->num_planes; ++plane) {
 218                                 planes[plane].m.offset =
 219                                         vb->planes[plane].m.offset;
 220                                 planes[plane].length =
 221                                         vb->planes[plane].length;
 222                         }
 223                         break;
 224                 }
 225 
 226                 /* Fill in driver-provided information for OUTPUT types */
 227                 if (V4L2_TYPE_IS_OUTPUT(b->type)) {
 228                         /*
 229                          * Will have to go up to b->length when API starts
 230                          * accepting variable number of planes.
 231                          *
 232                          * If bytesused == 0 for the output buffer, then fall
 233                          * back to the full buffer size. In that case
 234                          * userspace clearly never bothered to set it and
 235                          * it's a safe assumption that they really meant to
 236                          * use the full plane sizes.
 237                          *
 238                          * Some drivers, e.g. old codec drivers, use bytesused == 0
 239                          * as a way to indicate that streaming is finished.
 240                          * In that case, the driver should use the
 241                          * allow_zero_bytesused flag to keep old userspace
 242                          * applications working.
 243                          */
 244                         for (plane = 0; plane < vb->num_planes; ++plane) {
 245                                 struct vb2_plane *pdst = &planes[plane];
 246                                 struct v4l2_plane *psrc = &b->m.planes[plane];
 247 
 248                                 if (psrc->bytesused == 0)
 249                                         vb2_warn_zero_bytesused(vb);
 250 
 251                                 if (vb->vb2_queue->allow_zero_bytesused)
 252                                         pdst->bytesused = psrc->bytesused;
 253                                 else
 254                                         pdst->bytesused = psrc->bytesused ?
 255                                                 psrc->bytesused : pdst->length;
 256                                 pdst->data_offset = psrc->data_offset;
 257                         }
 258                 }
 259         } else {
 260                 /*
 261                  * Single-planar buffers do not use planes array,
 262                  * so fill in relevant v4l2_buffer struct fields instead.
 263                  * In videobuf we use our internal V4l2_planes struct for
 264                  * single-planar buffers as well, for simplicity.
 265                  *
 266                  * If bytesused == 0 for the output buffer, then fall back
 267                  * to the full buffer size as that's a sensible default.
 268                  *
 269                  * Some drivers, e.g. old codec drivers, use bytesused == 0 as
 270                  * a way to indicate that streaming is finished. In that case,
 271                  * the driver should use the allow_zero_bytesused flag to keep
 272                  * old userspace applications working.
 273                  */
 274                 switch (b->memory) {
 275                 case VB2_MEMORY_USERPTR:
 276                         planes[0].m.userptr = b->m.userptr;
 277                         planes[0].length = b->length;
 278                         break;
 279                 case VB2_MEMORY_DMABUF:
 280                         planes[0].m.fd = b->m.fd;
 281                         planes[0].length = b->length;
 282                         break;
 283                 default:
 284                         planes[0].m.offset = vb->planes[0].m.offset;
 285                         planes[0].length = vb->planes[0].length;
 286                         break;
 287                 }
 288 
 289                 planes[0].data_offset = 0;
 290                 if (V4L2_TYPE_IS_OUTPUT(b->type)) {
 291                         if (b->bytesused == 0)
 292                                 vb2_warn_zero_bytesused(vb);
 293 
 294                         if (vb->vb2_queue->allow_zero_bytesused)
 295                                 planes[0].bytesused = b->bytesused;
 296                         else
 297                                 planes[0].bytesused = b->bytesused ?
 298                                         b->bytesused : planes[0].length;
 299                 } else
 300                         planes[0].bytesused = 0;
 301 
 302         }
 303 
 304         /* Zero flags that we handle */
 305         vbuf->flags = b->flags & ~V4L2_BUFFER_MASK_FLAGS;
 306         if (!vb->vb2_queue->copy_timestamp || !V4L2_TYPE_IS_OUTPUT(b->type)) {
 307                 /*
 308                  * Non-COPY timestamps and non-OUTPUT queues will get
 309                  * their timestamp and timestamp source flags from the
 310                  * queue.
 311                  */
 312                 vbuf->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
 313         }
 314 
 315         if (V4L2_TYPE_IS_OUTPUT(b->type)) {
 316                 /*
 317                  * For output buffers mask out the timecode flag:
 318                  * this will be handled later in vb2_qbuf().
 319                  * The 'field' is valid metadata for this output buffer
 320                  * and so that needs to be copied here.
 321                  */
 322                 vbuf->flags &= ~V4L2_BUF_FLAG_TIMECODE;
 323                 vbuf->field = b->field;
 324         } else {
 325                 /* Zero any output buffer flags as this is a capture buffer */
 326                 vbuf->flags &= ~V4L2_BUFFER_OUT_FLAGS;
 327                 /* Zero last flag, this is a signal from driver to userspace */
 328                 vbuf->flags &= ~V4L2_BUF_FLAG_LAST;
 329         }
 330 
 331         return 0;
 332 }
 333 
 334 static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *mdev,
 335                                     struct v4l2_buffer *b, bool is_prepare,
 336                                     struct media_request **p_req)
 337 {
 338         const char *opname = is_prepare ? "prepare_buf" : "qbuf";
 339         struct media_request *req;
 340         struct vb2_v4l2_buffer *vbuf;
 341         struct vb2_buffer *vb;
 342         int ret;
 343 
 344         if (b->type != q->type) {
 345                 dprintk(1, "%s: invalid buffer type\n", opname);
 346                 return -EINVAL;
 347         }
 348 
 349         if (b->index >= q->num_buffers) {
 350                 dprintk(1, "%s: buffer index out of range\n", opname);
 351                 return -EINVAL;
 352         }
 353 
 354         if (q->bufs[b->index] == NULL) {
 355                 /* Should never happen */
 356                 dprintk(1, "%s: buffer is NULL\n", opname);
 357                 return -EINVAL;
 358         }
 359 
 360         if (b->memory != q->memory) {
 361                 dprintk(1, "%s: invalid memory type\n", opname);
 362                 return -EINVAL;
 363         }
 364 
 365         vb = q->bufs[b->index];
 366         vbuf = to_vb2_v4l2_buffer(vb);
 367         ret = __verify_planes_array(vb, b);
 368         if (ret)
 369                 return ret;
 370 
 371         if (!is_prepare && (b->flags & V4L2_BUF_FLAG_REQUEST_FD) &&
 372             vb->state != VB2_BUF_STATE_DEQUEUED) {
 373                 dprintk(1, "%s: buffer is not in dequeued state\n", opname);
 374                 return -EINVAL;
 375         }
 376 
 377         if (!vb->prepared) {
 378                 /* Copy relevant information provided by the userspace */
 379                 memset(vbuf->planes, 0,
 380                        sizeof(vbuf->planes[0]) * vb->num_planes);
 381                 ret = vb2_fill_vb2_v4l2_buffer(vb, b);
 382                 if (ret)
 383                         return ret;
 384         }
 385 
 386         if (is_prepare)
 387                 return 0;
 388 
 389         if (!(b->flags & V4L2_BUF_FLAG_REQUEST_FD)) {
 390                 if (q->requires_requests) {
 391                         dprintk(1, "%s: queue requires requests\n", opname);
 392                         return -EBADR;
 393                 }
 394                 if (q->uses_requests) {
 395                         dprintk(1, "%s: queue uses requests\n", opname);
 396                         return -EBUSY;
 397                 }
 398                 return 0;
 399         } else if (!q->supports_requests) {
 400                 dprintk(1, "%s: queue does not support requests\n", opname);
 401                 return -EBADR;
 402         } else if (q->uses_qbuf) {
 403                 dprintk(1, "%s: queue does not use requests\n", opname);
 404                 return -EBUSY;
 405         }
 406 
 407         /*
 408          * For proper locking when queueing a request you need to be able
 409          * to lock access to the vb2 queue, so check that there is a lock
 410          * that we can use. In addition p_req must be non-NULL.
 411          */
 412         if (WARN_ON(!q->lock || !p_req))
 413                 return -EINVAL;
 414 
 415         /*
 416          * Make sure this op is implemented by the driver. It's easy to forget
 417          * this callback, but is it important when canceling a buffer in a
 418          * queued request.
 419          */
 420         if (WARN_ON(!q->ops->buf_request_complete))
 421                 return -EINVAL;
 422         /*
 423          * Make sure this op is implemented by the driver for the output queue.
 424          * It's easy to forget this callback, but is it important to correctly
 425          * validate the 'field' value at QBUF time.
 426          */
 427         if (WARN_ON((q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT ||
 428                      q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) &&
 429                     !q->ops->buf_out_validate))
 430                 return -EINVAL;
 431 
 432         if (b->request_fd < 0) {
 433                 dprintk(1, "%s: request_fd < 0\n", opname);
 434                 return -EINVAL;
 435         }
 436 
 437         req = media_request_get_by_fd(mdev, b->request_fd);
 438         if (IS_ERR(req)) {
 439                 dprintk(1, "%s: invalid request_fd\n", opname);
 440                 return PTR_ERR(req);
 441         }
 442 
 443         /*
 444          * Early sanity check. This is checked again when the buffer
 445          * is bound to the request in vb2_core_qbuf().
 446          */
 447         if (req->state != MEDIA_REQUEST_STATE_IDLE &&
 448             req->state != MEDIA_REQUEST_STATE_UPDATING) {
 449                 dprintk(1, "%s: request is not idle\n", opname);
 450                 media_request_put(req);
 451                 return -EBUSY;
 452         }
 453 
 454         *p_req = req;
 455         vbuf->request_fd = b->request_fd;
 456 
 457         return 0;
 458 }
 459 
 460 /*
 461  * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be
 462  * returned to userspace
 463  */
 464 static void __fill_v4l2_buffer(struct vb2_buffer *vb, void *pb)
 465 {
 466         struct v4l2_buffer *b = pb;
 467         struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
 468         struct vb2_queue *q = vb->vb2_queue;
 469         unsigned int plane;
 470 
 471         /* Copy back data such as timestamp, flags, etc. */
 472         b->index = vb->index;
 473         b->type = vb->type;
 474         b->memory = vb->memory;
 475         b->bytesused = 0;
 476 
 477         b->flags = vbuf->flags;
 478         b->field = vbuf->field;
 479         b->timestamp = ns_to_timeval(vb->timestamp);
 480         b->timecode = vbuf->timecode;
 481         b->sequence = vbuf->sequence;
 482         b->reserved2 = 0;
 483         b->request_fd = 0;
 484 
 485         if (q->is_multiplanar) {
 486                 /*
 487                  * Fill in plane-related data if userspace provided an array
 488                  * for it. The caller has already verified memory and size.
 489                  */
 490                 b->length = vb->num_planes;
 491                 for (plane = 0; plane < vb->num_planes; ++plane) {
 492                         struct v4l2_plane *pdst = &b->m.planes[plane];
 493                         struct vb2_plane *psrc = &vb->planes[plane];
 494 
 495                         pdst->bytesused = psrc->bytesused;
 496                         pdst->length = psrc->length;
 497                         if (q->memory == VB2_MEMORY_MMAP)
 498                                 pdst->m.mem_offset = psrc->m.offset;
 499                         else if (q->memory == VB2_MEMORY_USERPTR)
 500                                 pdst->m.userptr = psrc->m.userptr;
 501                         else if (q->memory == VB2_MEMORY_DMABUF)
 502                                 pdst->m.fd = psrc->m.fd;
 503                         pdst->data_offset = psrc->data_offset;
 504                         memset(pdst->reserved, 0, sizeof(pdst->reserved));
 505                 }
 506         } else {
 507                 /*
 508                  * We use length and offset in v4l2_planes array even for
 509                  * single-planar buffers, but userspace does not.
 510                  */
 511                 b->length = vb->planes[0].length;
 512                 b->bytesused = vb->planes[0].bytesused;
 513                 if (q->memory == VB2_MEMORY_MMAP)
 514                         b->m.offset = vb->planes[0].m.offset;
 515                 else if (q->memory == VB2_MEMORY_USERPTR)
 516                         b->m.userptr = vb->planes[0].m.userptr;
 517                 else if (q->memory == VB2_MEMORY_DMABUF)
 518                         b->m.fd = vb->planes[0].m.fd;
 519         }
 520 
 521         /*
 522          * Clear any buffer state related flags.
 523          */
 524         b->flags &= ~V4L2_BUFFER_MASK_FLAGS;
 525         b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK;
 526         if (!q->copy_timestamp) {
 527                 /*
 528                  * For non-COPY timestamps, drop timestamp source bits
 529                  * and obtain the timestamp source from the queue.
 530                  */
 531                 b->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
 532                 b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
 533         }
 534 
 535         switch (vb->state) {
 536         case VB2_BUF_STATE_QUEUED:
 537         case VB2_BUF_STATE_ACTIVE:
 538                 b->flags |= V4L2_BUF_FLAG_QUEUED;
 539                 break;
 540         case VB2_BUF_STATE_IN_REQUEST:
 541                 b->flags |= V4L2_BUF_FLAG_IN_REQUEST;
 542                 break;
 543         case VB2_BUF_STATE_ERROR:
 544                 b->flags |= V4L2_BUF_FLAG_ERROR;
 545                 /* fall through */
 546         case VB2_BUF_STATE_DONE:
 547                 b->flags |= V4L2_BUF_FLAG_DONE;
 548                 break;
 549         case VB2_BUF_STATE_PREPARING:
 550         case VB2_BUF_STATE_DEQUEUED:
 551                 /* nothing */
 552                 break;
 553         }
 554 
 555         if ((vb->state == VB2_BUF_STATE_DEQUEUED ||
 556              vb->state == VB2_BUF_STATE_IN_REQUEST) &&
 557             vb->synced && vb->prepared)
 558                 b->flags |= V4L2_BUF_FLAG_PREPARED;
 559 
 560         if (vb2_buffer_in_use(q, vb))
 561                 b->flags |= V4L2_BUF_FLAG_MAPPED;
 562         if (vbuf->request_fd >= 0) {
 563                 b->flags |= V4L2_BUF_FLAG_REQUEST_FD;
 564                 b->request_fd = vbuf->request_fd;
 565         }
 566 }
 567 
 568 /*
 569  * __fill_vb2_buffer() - fill a vb2_buffer with information provided in a
 570  * v4l2_buffer by the userspace. It also verifies that struct
 571  * v4l2_buffer has a valid number of planes.
 572  */
 573 static int __fill_vb2_buffer(struct vb2_buffer *vb, struct vb2_plane *planes)
 574 {
 575         struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
 576         unsigned int plane;
 577 
 578         if (!vb->vb2_queue->copy_timestamp)
 579                 vb->timestamp = 0;
 580 
 581         for (plane = 0; plane < vb->num_planes; ++plane) {
 582                 if (vb->vb2_queue->memory != VB2_MEMORY_MMAP) {
 583                         planes[plane].m = vbuf->planes[plane].m;
 584                         planes[plane].length = vbuf->planes[plane].length;
 585                 }
 586                 planes[plane].bytesused = vbuf->planes[plane].bytesused;
 587                 planes[plane].data_offset = vbuf->planes[plane].data_offset;
 588         }
 589         return 0;
 590 }
 591 
 592 static const struct vb2_buf_ops v4l2_buf_ops = {
 593         .verify_planes_array    = __verify_planes_array_core,
 594         .init_buffer            = __init_vb2_v4l2_buffer,
 595         .fill_user_buffer       = __fill_v4l2_buffer,
 596         .fill_vb2_buffer        = __fill_vb2_buffer,
 597         .copy_timestamp         = __copy_timestamp,
 598 };
 599 
 600 int vb2_find_timestamp(const struct vb2_queue *q, u64 timestamp,
 601                        unsigned int start_idx)
 602 {
 603         unsigned int i;
 604 
 605         for (i = start_idx; i < q->num_buffers; i++)
 606                 if (q->bufs[i]->copied_timestamp &&
 607                     q->bufs[i]->timestamp == timestamp)
 608                         return i;
 609         return -1;
 610 }
 611 EXPORT_SYMBOL_GPL(vb2_find_timestamp);
 612 
 613 /*
 614  * vb2_querybuf() - query video buffer information
 615  * @q:          videobuf queue
 616  * @b:          buffer struct passed from userspace to vidioc_querybuf handler
 617  *              in driver
 618  *
 619  * Should be called from vidioc_querybuf ioctl handler in driver.
 620  * This function will verify the passed v4l2_buffer structure and fill the
 621  * relevant information for the userspace.
 622  *
 623  * The return values from this function are intended to be directly returned
 624  * from vidioc_querybuf handler in driver.
 625  */
 626 int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b)
 627 {
 628         struct vb2_buffer *vb;
 629         int ret;
 630 
 631         if (b->type != q->type) {
 632                 dprintk(1, "wrong buffer type\n");
 633                 return -EINVAL;
 634         }
 635 
 636         if (b->index >= q->num_buffers) {
 637                 dprintk(1, "buffer index out of range\n");
 638                 return -EINVAL;
 639         }
 640         vb = q->bufs[b->index];
 641         ret = __verify_planes_array(vb, b);
 642         if (!ret)
 643                 vb2_core_querybuf(q, b->index, b);
 644         return ret;
 645 }
 646 EXPORT_SYMBOL(vb2_querybuf);
 647 
 648 static void fill_buf_caps(struct vb2_queue *q, u32 *caps)
 649 {
 650         *caps = V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS;
 651         if (q->io_modes & VB2_MMAP)
 652                 *caps |= V4L2_BUF_CAP_SUPPORTS_MMAP;
 653         if (q->io_modes & VB2_USERPTR)
 654                 *caps |= V4L2_BUF_CAP_SUPPORTS_USERPTR;
 655         if (q->io_modes & VB2_DMABUF)
 656                 *caps |= V4L2_BUF_CAP_SUPPORTS_DMABUF;
 657 #ifdef CONFIG_MEDIA_CONTROLLER_REQUEST_API
 658         if (q->supports_requests)
 659                 *caps |= V4L2_BUF_CAP_SUPPORTS_REQUESTS;
 660 #endif
 661 }
 662 
 663 int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
 664 {
 665         int ret = vb2_verify_memory_type(q, req->memory, req->type);
 666 
 667         fill_buf_caps(q, &req->capabilities);
 668         return ret ? ret : vb2_core_reqbufs(q, req->memory, &req->count);
 669 }
 670 EXPORT_SYMBOL_GPL(vb2_reqbufs);
 671 
 672 int vb2_prepare_buf(struct vb2_queue *q, struct media_device *mdev,
 673                     struct v4l2_buffer *b)
 674 {
 675         int ret;
 676 
 677         if (vb2_fileio_is_active(q)) {
 678                 dprintk(1, "file io in progress\n");
 679                 return -EBUSY;
 680         }
 681 
 682         if (b->flags & V4L2_BUF_FLAG_REQUEST_FD)
 683                 return -EINVAL;
 684 
 685         ret = vb2_queue_or_prepare_buf(q, mdev, b, true, NULL);
 686 
 687         return ret ? ret : vb2_core_prepare_buf(q, b->index, b);
 688 }
 689 EXPORT_SYMBOL_GPL(vb2_prepare_buf);
 690 
 691 int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
 692 {
 693         unsigned requested_planes = 1;
 694         unsigned requested_sizes[VIDEO_MAX_PLANES];
 695         struct v4l2_format *f = &create->format;
 696         int ret = vb2_verify_memory_type(q, create->memory, f->type);
 697         unsigned i;
 698 
 699         fill_buf_caps(q, &create->capabilities);
 700         create->index = q->num_buffers;
 701         if (create->count == 0)
 702                 return ret != -EBUSY ? ret : 0;
 703 
 704         switch (f->type) {
 705         case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
 706         case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
 707                 requested_planes = f->fmt.pix_mp.num_planes;
 708                 if (requested_planes == 0 ||
 709                     requested_planes > VIDEO_MAX_PLANES)
 710                         return -EINVAL;
 711                 for (i = 0; i < requested_planes; i++)
 712                         requested_sizes[i] =
 713                                 f->fmt.pix_mp.plane_fmt[i].sizeimage;
 714                 break;
 715         case V4L2_BUF_TYPE_VIDEO_CAPTURE:
 716         case V4L2_BUF_TYPE_VIDEO_OUTPUT:
 717                 requested_sizes[0] = f->fmt.pix.sizeimage;
 718                 break;
 719         case V4L2_BUF_TYPE_VBI_CAPTURE:
 720         case V4L2_BUF_TYPE_VBI_OUTPUT:
 721                 requested_sizes[0] = f->fmt.vbi.samples_per_line *
 722                         (f->fmt.vbi.count[0] + f->fmt.vbi.count[1]);
 723                 break;
 724         case V4L2_BUF_TYPE_SLICED_VBI_CAPTURE:
 725         case V4L2_BUF_TYPE_SLICED_VBI_OUTPUT:
 726                 requested_sizes[0] = f->fmt.sliced.io_size;
 727                 break;
 728         case V4L2_BUF_TYPE_SDR_CAPTURE:
 729         case V4L2_BUF_TYPE_SDR_OUTPUT:
 730                 requested_sizes[0] = f->fmt.sdr.buffersize;
 731                 break;
 732         case V4L2_BUF_TYPE_META_CAPTURE:
 733         case V4L2_BUF_TYPE_META_OUTPUT:
 734                 requested_sizes[0] = f->fmt.meta.buffersize;
 735                 break;
 736         default:
 737                 return -EINVAL;
 738         }
 739         for (i = 0; i < requested_planes; i++)
 740                 if (requested_sizes[i] == 0)
 741                         return -EINVAL;
 742         return ret ? ret : vb2_core_create_bufs(q, create->memory,
 743                 &create->count, requested_planes, requested_sizes);
 744 }
 745 EXPORT_SYMBOL_GPL(vb2_create_bufs);
 746 
 747 int vb2_qbuf(struct vb2_queue *q, struct media_device *mdev,
 748              struct v4l2_buffer *b)
 749 {
 750         struct media_request *req = NULL;
 751         int ret;
 752 
 753         if (vb2_fileio_is_active(q)) {
 754                 dprintk(1, "file io in progress\n");
 755                 return -EBUSY;
 756         }
 757 
 758         ret = vb2_queue_or_prepare_buf(q, mdev, b, false, &req);
 759         if (ret)
 760                 return ret;
 761         ret = vb2_core_qbuf(q, b->index, b, req);
 762         if (req)
 763                 media_request_put(req);
 764         return ret;
 765 }
 766 EXPORT_SYMBOL_GPL(vb2_qbuf);
 767 
 768 int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking)
 769 {
 770         int ret;
 771 
 772         if (vb2_fileio_is_active(q)) {
 773                 dprintk(1, "file io in progress\n");
 774                 return -EBUSY;
 775         }
 776 
 777         if (b->type != q->type) {
 778                 dprintk(1, "invalid buffer type\n");
 779                 return -EINVAL;
 780         }
 781 
 782         ret = vb2_core_dqbuf(q, NULL, b, nonblocking);
 783 
 784         if (!q->is_output &&
 785             b->flags & V4L2_BUF_FLAG_DONE &&
 786             b->flags & V4L2_BUF_FLAG_LAST)
 787                 q->last_buffer_dequeued = true;
 788 
 789         /*
 790          *  After calling the VIDIOC_DQBUF V4L2_BUF_FLAG_DONE must be
 791          *  cleared.
 792          */
 793         b->flags &= ~V4L2_BUF_FLAG_DONE;
 794 
 795         return ret;
 796 }
 797 EXPORT_SYMBOL_GPL(vb2_dqbuf);
 798 
 799 int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type)
 800 {
 801         if (vb2_fileio_is_active(q)) {
 802                 dprintk(1, "file io in progress\n");
 803                 return -EBUSY;
 804         }
 805         return vb2_core_streamon(q, type);
 806 }
 807 EXPORT_SYMBOL_GPL(vb2_streamon);
 808 
 809 int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type)
 810 {
 811         if (vb2_fileio_is_active(q)) {
 812                 dprintk(1, "file io in progress\n");
 813                 return -EBUSY;
 814         }
 815         return vb2_core_streamoff(q, type);
 816 }
 817 EXPORT_SYMBOL_GPL(vb2_streamoff);
 818 
 819 int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb)
 820 {
 821         return vb2_core_expbuf(q, &eb->fd, eb->type, eb->index,
 822                                 eb->plane, eb->flags);
 823 }
 824 EXPORT_SYMBOL_GPL(vb2_expbuf);
 825 
 826 int vb2_queue_init(struct vb2_queue *q)
 827 {
 828         /*
 829          * Sanity check
 830          */
 831         if (WARN_ON(!q)                   ||
 832             WARN_ON(q->timestamp_flags &
 833                     ~(V4L2_BUF_FLAG_TIMESTAMP_MASK |
 834                       V4L2_BUF_FLAG_TSTAMP_SRC_MASK)))
 835                 return -EINVAL;
 836 
 837         /* Warn that the driver should choose an appropriate timestamp type */
 838         WARN_ON((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) ==
 839                 V4L2_BUF_FLAG_TIMESTAMP_UNKNOWN);
 840 
 841         /* Warn that vb2_memory should match with v4l2_memory */
 842         if (WARN_ON(VB2_MEMORY_MMAP != (int)V4L2_MEMORY_MMAP)
 843                 || WARN_ON(VB2_MEMORY_USERPTR != (int)V4L2_MEMORY_USERPTR)
 844                 || WARN_ON(VB2_MEMORY_DMABUF != (int)V4L2_MEMORY_DMABUF))
 845                 return -EINVAL;
 846 
 847         if (q->buf_struct_size == 0)
 848                 q->buf_struct_size = sizeof(struct vb2_v4l2_buffer);
 849 
 850         q->buf_ops = &v4l2_buf_ops;
 851         q->is_multiplanar = V4L2_TYPE_IS_MULTIPLANAR(q->type);
 852         q->is_output = V4L2_TYPE_IS_OUTPUT(q->type);
 853         q->copy_timestamp = (q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK)
 854                         == V4L2_BUF_FLAG_TIMESTAMP_COPY;
 855         /*
 856          * For compatibility with vb1: if QBUF hasn't been called yet, then
 857          * return EPOLLERR as well. This only affects capture queues, output
 858          * queues will always initialize waiting_for_buffers to false.
 859          */
 860         q->quirk_poll_must_check_waiting_for_buffers = true;
 861 
 862         return vb2_core_queue_init(q);
 863 }
 864 EXPORT_SYMBOL_GPL(vb2_queue_init);
 865 
 866 void vb2_queue_release(struct vb2_queue *q)
 867 {
 868         vb2_core_queue_release(q);
 869 }
 870 EXPORT_SYMBOL_GPL(vb2_queue_release);
 871 
 872 __poll_t vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
 873 {
 874         struct video_device *vfd = video_devdata(file);
 875         __poll_t res;
 876 
 877         res = vb2_core_poll(q, file, wait);
 878 
 879         if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) {
 880                 struct v4l2_fh *fh = file->private_data;
 881 
 882                 poll_wait(file, &fh->wait, wait);
 883                 if (v4l2_event_pending(fh))
 884                         res |= EPOLLPRI;
 885         }
 886 
 887         return res;
 888 }
 889 EXPORT_SYMBOL_GPL(vb2_poll);
 890 
 891 /*
 892  * The following functions are not part of the vb2 core API, but are helper
 893  * functions that plug into struct v4l2_ioctl_ops, struct v4l2_file_operations
 894  * and struct vb2_ops.
 895  * They contain boilerplate code that most if not all drivers have to do
 896  * and so they simplify the driver code.
 897  */
 898 
 899 /* The queue is busy if there is a owner and you are not that owner. */
 900 static inline bool vb2_queue_is_busy(struct video_device *vdev, struct file *file)
 901 {
 902         return vdev->queue->owner && vdev->queue->owner != file->private_data;
 903 }
 904 
 905 /* vb2 ioctl helpers */
 906 
 907 int vb2_ioctl_reqbufs(struct file *file, void *priv,
 908                           struct v4l2_requestbuffers *p)
 909 {
 910         struct video_device *vdev = video_devdata(file);
 911         int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type);
 912 
 913         fill_buf_caps(vdev->queue, &p->capabilities);
 914         if (res)
 915                 return res;
 916         if (vb2_queue_is_busy(vdev, file))
 917                 return -EBUSY;
 918         res = vb2_core_reqbufs(vdev->queue, p->memory, &p->count);
 919         /* If count == 0, then the owner has released all buffers and he
 920            is no longer owner of the queue. Otherwise we have a new owner. */
 921         if (res == 0)
 922                 vdev->queue->owner = p->count ? file->private_data : NULL;
 923         return res;
 924 }
 925 EXPORT_SYMBOL_GPL(vb2_ioctl_reqbufs);
 926 
 927 int vb2_ioctl_create_bufs(struct file *file, void *priv,
 928                           struct v4l2_create_buffers *p)
 929 {
 930         struct video_device *vdev = video_devdata(file);
 931         int res = vb2_verify_memory_type(vdev->queue, p->memory,
 932                         p->format.type);
 933 
 934         p->index = vdev->queue->num_buffers;
 935         fill_buf_caps(vdev->queue, &p->capabilities);
 936         /*
 937          * If count == 0, then just check if memory and type are valid.
 938          * Any -EBUSY result from vb2_verify_memory_type can be mapped to 0.
 939          */
 940         if (p->count == 0)
 941                 return res != -EBUSY ? res : 0;
 942         if (res)
 943                 return res;
 944         if (vb2_queue_is_busy(vdev, file))
 945                 return -EBUSY;
 946 
 947         res = vb2_create_bufs(vdev->queue, p);
 948         if (res == 0)
 949                 vdev->queue->owner = file->private_data;
 950         return res;
 951 }
 952 EXPORT_SYMBOL_GPL(vb2_ioctl_create_bufs);
 953 
 954 int vb2_ioctl_prepare_buf(struct file *file, void *priv,
 955                           struct v4l2_buffer *p)
 956 {
 957         struct video_device *vdev = video_devdata(file);
 958 
 959         if (vb2_queue_is_busy(vdev, file))
 960                 return -EBUSY;
 961         return vb2_prepare_buf(vdev->queue, vdev->v4l2_dev->mdev, p);
 962 }
 963 EXPORT_SYMBOL_GPL(vb2_ioctl_prepare_buf);
 964 
 965 int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p)
 966 {
 967         struct video_device *vdev = video_devdata(file);
 968 
 969         /* No need to call vb2_queue_is_busy(), anyone can query buffers. */
 970         return vb2_querybuf(vdev->queue, p);
 971 }
 972 EXPORT_SYMBOL_GPL(vb2_ioctl_querybuf);
 973 
 974 int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p)
 975 {
 976         struct video_device *vdev = video_devdata(file);
 977 
 978         if (vb2_queue_is_busy(vdev, file))
 979                 return -EBUSY;
 980         return vb2_qbuf(vdev->queue, vdev->v4l2_dev->mdev, p);
 981 }
 982 EXPORT_SYMBOL_GPL(vb2_ioctl_qbuf);
 983 
 984 int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p)
 985 {
 986         struct video_device *vdev = video_devdata(file);
 987 
 988         if (vb2_queue_is_busy(vdev, file))
 989                 return -EBUSY;
 990         return vb2_dqbuf(vdev->queue, p, file->f_flags & O_NONBLOCK);
 991 }
 992 EXPORT_SYMBOL_GPL(vb2_ioctl_dqbuf);
 993 
 994 int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i)
 995 {
 996         struct video_device *vdev = video_devdata(file);
 997 
 998         if (vb2_queue_is_busy(vdev, file))
 999                 return -EBUSY;
1000         return vb2_streamon(vdev->queue, i);
1001 }
1002 EXPORT_SYMBOL_GPL(vb2_ioctl_streamon);
1003 
1004 int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i)
1005 {
1006         struct video_device *vdev = video_devdata(file);
1007 
1008         if (vb2_queue_is_busy(vdev, file))
1009                 return -EBUSY;
1010         return vb2_streamoff(vdev->queue, i);
1011 }
1012 EXPORT_SYMBOL_GPL(vb2_ioctl_streamoff);
1013 
1014 int vb2_ioctl_expbuf(struct file *file, void *priv, struct v4l2_exportbuffer *p)
1015 {
1016         struct video_device *vdev = video_devdata(file);
1017 
1018         if (vb2_queue_is_busy(vdev, file))
1019                 return -EBUSY;
1020         return vb2_expbuf(vdev->queue, p);
1021 }
1022 EXPORT_SYMBOL_GPL(vb2_ioctl_expbuf);
1023 
1024 /* v4l2_file_operations helpers */
1025 
1026 int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma)
1027 {
1028         struct video_device *vdev = video_devdata(file);
1029 
1030         return vb2_mmap(vdev->queue, vma);
1031 }
1032 EXPORT_SYMBOL_GPL(vb2_fop_mmap);
1033 
1034 int _vb2_fop_release(struct file *file, struct mutex *lock)
1035 {
1036         struct video_device *vdev = video_devdata(file);
1037 
1038         if (lock)
1039                 mutex_lock(lock);
1040         if (file->private_data == vdev->queue->owner) {
1041                 vb2_queue_release(vdev->queue);
1042                 vdev->queue->owner = NULL;
1043         }
1044         if (lock)
1045                 mutex_unlock(lock);
1046         return v4l2_fh_release(file);
1047 }
1048 EXPORT_SYMBOL_GPL(_vb2_fop_release);
1049 
1050 int vb2_fop_release(struct file *file)
1051 {
1052         struct video_device *vdev = video_devdata(file);
1053         struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
1054 
1055         return _vb2_fop_release(file, lock);
1056 }
1057 EXPORT_SYMBOL_GPL(vb2_fop_release);
1058 
1059 ssize_t vb2_fop_write(struct file *file, const char __user *buf,
1060                 size_t count, loff_t *ppos)
1061 {
1062         struct video_device *vdev = video_devdata(file);
1063         struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
1064         int err = -EBUSY;
1065 
1066         if (!(vdev->queue->io_modes & VB2_WRITE))
1067                 return -EINVAL;
1068         if (lock && mutex_lock_interruptible(lock))
1069                 return -ERESTARTSYS;
1070         if (vb2_queue_is_busy(vdev, file))
1071                 goto exit;
1072         err = vb2_write(vdev->queue, buf, count, ppos,
1073                        file->f_flags & O_NONBLOCK);
1074         if (vdev->queue->fileio)
1075                 vdev->queue->owner = file->private_data;
1076 exit:
1077         if (lock)
1078                 mutex_unlock(lock);
1079         return err;
1080 }
1081 EXPORT_SYMBOL_GPL(vb2_fop_write);
1082 
1083 ssize_t vb2_fop_read(struct file *file, char __user *buf,
1084                 size_t count, loff_t *ppos)
1085 {
1086         struct video_device *vdev = video_devdata(file);
1087         struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
1088         int err = -EBUSY;
1089 
1090         if (!(vdev->queue->io_modes & VB2_READ))
1091                 return -EINVAL;
1092         if (lock && mutex_lock_interruptible(lock))
1093                 return -ERESTARTSYS;
1094         if (vb2_queue_is_busy(vdev, file))
1095                 goto exit;
1096         err = vb2_read(vdev->queue, buf, count, ppos,
1097                        file->f_flags & O_NONBLOCK);
1098         if (vdev->queue->fileio)
1099                 vdev->queue->owner = file->private_data;
1100 exit:
1101         if (lock)
1102                 mutex_unlock(lock);
1103         return err;
1104 }
1105 EXPORT_SYMBOL_GPL(vb2_fop_read);
1106 
1107 __poll_t vb2_fop_poll(struct file *file, poll_table *wait)
1108 {
1109         struct video_device *vdev = video_devdata(file);
1110         struct vb2_queue *q = vdev->queue;
1111         struct mutex *lock = q->lock ? q->lock : vdev->lock;
1112         __poll_t res;
1113         void *fileio;
1114 
1115         /*
1116          * If this helper doesn't know how to lock, then you shouldn't be using
1117          * it but you should write your own.
1118          */
1119         WARN_ON(!lock);
1120 
1121         if (lock && mutex_lock_interruptible(lock))
1122                 return EPOLLERR;
1123 
1124         fileio = q->fileio;
1125 
1126         res = vb2_poll(vdev->queue, file, wait);
1127 
1128         /* If fileio was started, then we have a new queue owner. */
1129         if (!fileio && q->fileio)
1130                 q->owner = file->private_data;
1131         if (lock)
1132                 mutex_unlock(lock);
1133         return res;
1134 }
1135 EXPORT_SYMBOL_GPL(vb2_fop_poll);
1136 
1137 #ifndef CONFIG_MMU
1138 unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr,
1139                 unsigned long len, unsigned long pgoff, unsigned long flags)
1140 {
1141         struct video_device *vdev = video_devdata(file);
1142 
1143         return vb2_get_unmapped_area(vdev->queue, addr, len, pgoff, flags);
1144 }
1145 EXPORT_SYMBOL_GPL(vb2_fop_get_unmapped_area);
1146 #endif
1147 
1148 /* vb2_ops helpers. Only use if vq->lock is non-NULL. */
1149 
1150 void vb2_ops_wait_prepare(struct vb2_queue *vq)
1151 {
1152         mutex_unlock(vq->lock);
1153 }
1154 EXPORT_SYMBOL_GPL(vb2_ops_wait_prepare);
1155 
1156 void vb2_ops_wait_finish(struct vb2_queue *vq)
1157 {
1158         mutex_lock(vq->lock);
1159 }
1160 EXPORT_SYMBOL_GPL(vb2_ops_wait_finish);
1161 
1162 /*
1163  * Note that this function is called during validation time and
1164  * thus the req_queue_mutex is held to ensure no request objects
1165  * can be added or deleted while validating. So there is no need
1166  * to protect the objects list.
1167  */
1168 int vb2_request_validate(struct media_request *req)
1169 {
1170         struct media_request_object *obj;
1171         int ret = 0;
1172 
1173         if (!vb2_request_buffer_cnt(req))
1174                 return -ENOENT;
1175 
1176         list_for_each_entry(obj, &req->objects, list) {
1177                 if (!obj->ops->prepare)
1178                         continue;
1179 
1180                 ret = obj->ops->prepare(obj);
1181                 if (ret)
1182                         break;
1183         }
1184 
1185         if (ret) {
1186                 list_for_each_entry_continue_reverse(obj, &req->objects, list)
1187                         if (obj->ops->unprepare)
1188                                 obj->ops->unprepare(obj);
1189                 return ret;
1190         }
1191         return 0;
1192 }
1193 EXPORT_SYMBOL_GPL(vb2_request_validate);
1194 
1195 void vb2_request_queue(struct media_request *req)
1196 {
1197         struct media_request_object *obj, *obj_safe;
1198 
1199         /*
1200          * Queue all objects. Note that buffer objects are at the end of the
1201          * objects list, after all other object types. Once buffer objects
1202          * are queued, the driver might delete them immediately (if the driver
1203          * processes the buffer at once), so we have to use
1204          * list_for_each_entry_safe() to handle the case where the object we
1205          * queue is deleted.
1206          */
1207         list_for_each_entry_safe(obj, obj_safe, &req->objects, list)
1208                 if (obj->ops->queue)
1209                         obj->ops->queue(obj);
1210 }
1211 EXPORT_SYMBOL_GPL(vb2_request_queue);
1212 
1213 MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2");
1214 MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski");
1215 MODULE_LICENSE("GPL");
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/media/common/videobuf2/videobuf2-v4l2.c

DEFINITIONS
