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

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