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(op, vb, args...)                                 \
  72 ({                                                                      \
  73         struct vb2_queue *_q = (vb)->vb2_queue;                         \
  74         void *ptr;                                                      \
  75                                                                         \
  76         log_memop(vb, op);                                              \
  77         ptr = _q->mem_ops->op ? _q->mem_ops->op(vb, args) : NULL;       \
  78         if (!IS_ERR_OR_NULL(ptr))                                       \
  79                 (vb)->cnt_mem_ ## op++;                                 \
  80         ptr;                                                            \
  81 })
  82
  83 #define call_void_memop(vb, op, args...)                                \
  84 ({                                                                      \
  85         struct vb2_queue *_q = (vb)->vb2_queue;                         \
  86                                                                         \
  87         log_memop(vb, op);                                              \
  88         if (_q->mem_ops->op)                                            \
  89                 _q->mem_ops->op(args);                                  \
  90         (vb)->cnt_mem_ ## op++;                                         \
  91 })
  92
  93 #define log_qop(q, op)                                                  \
  94         dprintk(q, 2, "call_qop(%s)%s\n", #op,                          \
  95                 (q)->ops->op ? "" : " (nop)")
  96
  97 #define call_qop(q, op, args...)                                        \
  98 ({                                                                      \
  99         int err;                                                        \
 100                                                                         \
 101         log_qop(q, op);                                                 \
 102         err = (q)->ops->op ? (q)->ops->op(args) : 0;                    \
 103         if (!err)                                                       \
 104                 (q)->cnt_ ## op++;                                      \
 105         err;                                                            \
 106 })
 107
 108 #define call_void_qop(q, op, args...)                                   \
 109 ({                                                                      \
 110         log_qop(q, op);                                                 \
 111         if ((q)->ops->op)                                               \
 112                 (q)->ops->op(args);                                     \
 113         (q)->cnt_ ## op++;                                              \
 114 })
 115
 116 #define log_vb_qop(vb, op, args...)                                     \
 117         dprintk((vb)->vb2_queue, 2, "call_vb_qop(%d, %s)%s\n",          \
 118                 (vb)->index, #op,                                       \
 119                 (vb)->vb2_queue->ops->op ? "" : " (nop)")
 120
 121 #define call_vb_qop(vb, op, args...)                                    \
 122 ({                                                                      \
 123         int err;                                                        \
 124                                                                         \
 125         log_vb_qop(vb, op);                                             \
 126         err = (vb)->vb2_queue->ops->op ?                                \
 127                 (vb)->vb2_queue->ops->op(args) : 0;                     \
 128         if (!err)                                                       \
 129                 (vb)->cnt_ ## op++;                                     \
 130         err;                                                            \
 131 })
 132
 133 #define call_void_vb_qop(vb, op, args...)                               \
 134 ({                                                                      \
 135         log_vb_qop(vb, op);                                             \
 136         if ((vb)->vb2_queue->ops->op)                                   \
 137                 (vb)->vb2_queue->ops->op(args);                         \
 138         (vb)->cnt_ ## op++;                                             \
 139 })
 140
 141 #else
 142
 143 #define call_memop(vb, op, args...)                                     \
 144         ((vb)->vb2_queue->mem_ops->op ?                                 \
 145                 (vb)->vb2_queue->mem_ops->op(args) : 0)
 146
 147 #define call_ptr_memop(op, vb, args...)                                 \
 148         ((vb)->vb2_queue->mem_ops->op ?                                 \
 149                 (vb)->vb2_queue->mem_ops->op(vb, args) : NULL)
 150
 151 #define call_void_memop(vb, op, args...)                                \
 152         do {                                                            \
 153                 if ((vb)->vb2_queue->mem_ops->op)                       \
 154                         (vb)->vb2_queue->mem_ops->op(args);             \
 155         } while (0)
 156
 157 #define call_qop(q, op, args...)                                        \
 158         ((q)->ops->op ? (q)->ops->op(args) : 0)
 159
 160 #define call_void_qop(q, op, args...)                                   \
 161         do {                                                            \
 162                 if ((q)->ops->op)                                       \
 163                         (q)->ops->op(args);                             \
 164         } while (0)
 165
 166 #define call_vb_qop(vb, op, args...)                                    \
 167         ((vb)->vb2_queue->ops->op ? (vb)->vb2_queue->ops->op(args) : 0)
 168
 169 #define call_void_vb_qop(vb, op, args...)                               \
 170         do {                                                            \
 171                 if ((vb)->vb2_queue->ops->op)                           \
 172                         (vb)->vb2_queue->ops->op(args);                 \
 173         } while (0)
 174
 175 #endif
 176
 177 #define call_bufop(q, op, args...)                                      \
 178 ({                                                                      \
 179         int ret = 0;                                                    \
 180         if (q && q->buf_ops && q->buf_ops->op)                          \
 181                 ret = q->buf_ops->op(args);                             \
 182         ret;                                                            \
 183 })
 184
 185 #define call_void_bufop(q, op, args...)                                 \
 186 ({                                                                      \
 187         if (q && q->buf_ops && q->buf_ops->op)                          \
 188                 q->buf_ops->op(args);                                   \
 189 })
 190
 191 static void __vb2_queue_cancel(struct vb2_queue *q);
 192 static void __enqueue_in_driver(struct vb2_buffer *vb);
 193
 194 static const char *vb2_state_name(enum vb2_buffer_state s)
 195 {
 196         static const char * const state_names[] = {
 197                 [VB2_BUF_STATE_DEQUEUED] = "dequeued",
 198                 [VB2_BUF_STATE_IN_REQUEST] = "in request",
 199                 [VB2_BUF_STATE_PREPARING] = "preparing",
 200                 [VB2_BUF_STATE_QUEUED] = "queued",
 201                 [VB2_BUF_STATE_ACTIVE] = "active",
 202                 [VB2_BUF_STATE_DONE] = "done",
 203                 [VB2_BUF_STATE_ERROR] = "error",
 204         };
 205
 206         if ((unsigned int)(s) < ARRAY_SIZE(state_names))
 207                 return state_names[s];
 208         return "unknown";
 209 }
 210
 211 /*
 212  * __vb2_buf_mem_alloc() - allocate video memory for the given buffer
 213  */
 214 static int __vb2_buf_mem_alloc(struct vb2_buffer *vb)
 215 {
 216         struct vb2_queue *q = vb->vb2_queue;
 217         void *mem_priv;
 218         int plane;
 219         int ret = -ENOMEM;
 220
 221         /*
 222          * Allocate memory for all planes in this buffer
 223          * NOTE: mmapped areas should be page aligned
 224          */
 225         for (plane = 0; plane < vb->num_planes; ++plane) {
 226                 /* Memops alloc requires size to be page aligned. */
 227                 unsigned long size = PAGE_ALIGN(vb->planes[plane].length);
 228
 229                 /* Did it wrap around? */
 230                 if (size < vb->planes[plane].length)
 231                         goto free;
 232
 233                 mem_priv = call_ptr_memop(alloc,
 234                                           vb,
 235                                           q->alloc_devs[plane] ? : q->dev,
 236                                           size);
 237                 if (IS_ERR_OR_NULL(mem_priv)) {
 238                         if (mem_priv)
 239                                 ret = PTR_ERR(mem_priv);
 240                         goto free;
 241                 }
 242
 243                 /* Associate allocator private data with this plane */
 244                 vb->planes[plane].mem_priv = mem_priv;
 245         }
 246
 247         return 0;
 248 free:
 249         /* Free already allocated memory if one of the allocations failed */
 250         for (; plane > 0; --plane) {
 251                 call_void_memop(vb, put, vb->planes[plane - 1].mem_priv);
 252                 vb->planes[plane - 1].mem_priv = NULL;
 253         }
 254
 255         return ret;
 256 }
 257
 258 /*
 259  * __vb2_buf_mem_free() - free memory of the given buffer
 260  */
 261 static void __vb2_buf_mem_free(struct vb2_buffer *vb)
 262 {
 263         unsigned int plane;
 264
 265         for (plane = 0; plane < vb->num_planes; ++plane) {
 266                 call_void_memop(vb, put, vb->planes[plane].mem_priv);
 267                 vb->planes[plane].mem_priv = NULL;
 268                 dprintk(vb->vb2_queue, 3, "freed plane %d of buffer %d\n",
 269                         plane, vb->index);
 270         }
 271 }
 272
 273 /*
 274  * __vb2_buf_userptr_put() - release userspace memory associated with
 275  * a USERPTR buffer
 276  */
 277 static void __vb2_buf_userptr_put(struct vb2_buffer *vb)
 278 {
 279         unsigned int plane;
 280
 281         for (plane = 0; plane < vb->num_planes; ++plane) {
 282                 if (vb->planes[plane].mem_priv)
 283                         call_void_memop(vb, put_userptr, vb->planes[plane].mem_priv);
 284                 vb->planes[plane].mem_priv = NULL;
 285         }
 286 }
 287
 288 /*
 289  * __vb2_plane_dmabuf_put() - release memory associated with
 290  * a DMABUF shared plane
 291  */
 292 static void __vb2_plane_dmabuf_put(struct vb2_buffer *vb, struct vb2_plane *p)
 293 {
 294         if (!p->mem_priv)
 295                 return;
 296
 297         if (p->dbuf_mapped)
 298                 call_void_memop(vb, unmap_dmabuf, p->mem_priv);
 299
 300         call_void_memop(vb, detach_dmabuf, p->mem_priv);
 301         dma_buf_put(p->dbuf);
 302         p->mem_priv = NULL;
 303         p->dbuf = NULL;
 304         p->dbuf_mapped = 0;
 305 }
 306
 307 /*
 308  * __vb2_buf_dmabuf_put() - release memory associated with
 309  * a DMABUF shared buffer
 310  */
 311 static void __vb2_buf_dmabuf_put(struct vb2_buffer *vb)
 312 {
 313         unsigned int plane;
 314
 315         for (plane = 0; plane < vb->num_planes; ++plane)
 316                 __vb2_plane_dmabuf_put(vb, &vb->planes[plane]);
 317 }
 318
 319 /*
 320  * __vb2_buf_mem_prepare() - call ->prepare() on buffer's private memory
 321  * to sync caches
 322  */
 323 static void __vb2_buf_mem_prepare(struct vb2_buffer *vb)
 324 {
 325         unsigned int plane;
 326
 327         if (vb->synced)
 328                 return;
 329
 330         vb->synced = 1;
 331         for (plane = 0; plane < vb->num_planes; ++plane)
 332                 call_void_memop(vb, prepare, vb->planes[plane].mem_priv);
 333 }
 334
 335 /*
 336  * __vb2_buf_mem_finish() - call ->finish on buffer's private memory
 337  * to sync caches
 338  */
 339 static void __vb2_buf_mem_finish(struct vb2_buffer *vb)
 340 {
 341         unsigned int plane;
 342
 343         if (!vb->synced)
 344                 return;
 345
 346         vb->synced = 0;
 347         for (plane = 0; plane < vb->num_planes; ++plane)
 348                 call_void_memop(vb, finish, vb->planes[plane].mem_priv);
 349 }
 350
 351 /*
 352  * __setup_offsets() - setup unique offsets ("cookies") for every plane in
 353  * the buffer.
 354  */
 355 static void __setup_offsets(struct vb2_buffer *vb)
 356 {
 357         struct vb2_queue *q = vb->vb2_queue;
 358         unsigned int plane;
 359         unsigned long off = 0;
 360
 361         if (vb->index) {
 362                 struct vb2_buffer *prev = q->bufs[vb->index - 1];
 363                 struct vb2_plane *p = &prev->planes[prev->num_planes - 1];
 364
 365                 off = PAGE_ALIGN(p->m.offset + p->length);
 366         }
 367
 368         for (plane = 0; plane < vb->num_planes; ++plane) {
 369                 vb->planes[plane].m.offset = off;
 370
 371                 dprintk(q, 3, "buffer %d, plane %d offset 0x%08lx\n",
 372                                 vb->index, plane, off);
 373
 374                 off += vb->planes[plane].length;
 375                 off = PAGE_ALIGN(off);
 376         }
 377 }
 378
 379 static void init_buffer_cache_hints(struct vb2_queue *q, struct vb2_buffer *vb)
 380 {
 381         /*
 382          * DMA exporter should take care of cache syncs, so we can avoid
 383          * explicit ->prepare()/->finish() syncs. For other ->memory types
 384          * we always need ->prepare() or/and ->finish() cache sync.
 385          */
 386         if (q->memory == VB2_MEMORY_DMABUF) {
 387                 vb->skip_cache_sync_on_finish = 1;
 388                 vb->skip_cache_sync_on_prepare = 1;
 389                 return;
 390         }
 391
 392         /*
 393          * ->finish() cache sync can be avoided when queue direction is
 394          * TO_DEVICE.
 395          */
 396         if (q->dma_dir == DMA_TO_DEVICE)
 397                 vb->skip_cache_sync_on_finish = 1;
 398 }
 399
 400 /*
 401  * __vb2_queue_alloc() - allocate vb2 buffer structures and (for MMAP type)
 402  * video buffer memory for all buffers/planes on the queue and initializes the
 403  * queue
 404  *
 405  * Returns the number of buffers successfully allocated.
 406  */
 407 static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
 408                              unsigned int num_buffers, unsigned int num_planes,
 409                              const unsigned plane_sizes[VB2_MAX_PLANES])
 410 {
 411         unsigned int buffer, plane;
 412         struct vb2_buffer *vb;
 413         int ret;
 414
 415         /* Ensure that q->num_buffers+num_buffers is below VB2_MAX_FRAME */
 416         num_buffers = min_t(unsigned int, num_buffers,
 417                             VB2_MAX_FRAME - q->num_buffers);
 418
 419         for (buffer = 0; buffer < num_buffers; ++buffer) {
 420                 /* Allocate vb2 buffer structures */
 421                 vb = kzalloc(q->buf_struct_size, GFP_KERNEL);
 422                 if (!vb) {
 423                         dprintk(q, 1, "memory alloc for buffer struct failed\n");
 424                         break;
 425                 }
 426
 427                 vb->state = VB2_BUF_STATE_DEQUEUED;
 428                 vb->vb2_queue = q;
 429                 vb->num_planes = num_planes;
 430                 vb->index = q->num_buffers + buffer;
 431                 vb->type = q->type;
 432                 vb->memory = memory;
 433                 init_buffer_cache_hints(q, vb);
 434                 for (plane = 0; plane < num_planes; ++plane) {
 435                         vb->planes[plane].length = plane_sizes[plane];
 436                         vb->planes[plane].min_length = plane_sizes[plane];
 437                 }
 438                 call_void_bufop(q, init_buffer, vb);
 439
 440                 q->bufs[vb->index] = vb;
 441
 442                 /* Allocate video buffer memory for the MMAP type */
 443                 if (memory == VB2_MEMORY_MMAP) {
 444                         ret = __vb2_buf_mem_alloc(vb);
 445                         if (ret) {
 446                                 dprintk(q, 1, "failed allocating memory for buffer %d\n",
 447                                         buffer);
 448                                 q->bufs[vb->index] = NULL;
 449                                 kfree(vb);
 450                                 break;
 451                         }
 452                         __setup_offsets(vb);
 453                         /*
 454                          * Call the driver-provided buffer initialization
 455                          * callback, if given. An error in initialization
 456                          * results in queue setup failure.
 457                          */
 458                         ret = call_vb_qop(vb, buf_init, vb);
 459                         if (ret) {
 460                                 dprintk(q, 1, "buffer %d %p initialization failed\n",
 461                                         buffer, vb);
 462                                 __vb2_buf_mem_free(vb);
 463                                 q->bufs[vb->index] = NULL;
 464                                 kfree(vb);
 465                                 break;
 466                         }
 467                 }
 468         }
 469
 470         dprintk(q, 3, "allocated %d buffers, %d plane(s) each\n",
 471                 buffer, num_planes);
 472
 473         return buffer;
 474 }
 475
 476 /*
 477  * __vb2_free_mem() - release all video buffer memory for a given queue
 478  */
 479 static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers)
 480 {
 481         unsigned int buffer;
 482         struct vb2_buffer *vb;
 483
 484         for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
 485              ++buffer) {
 486                 vb = q->bufs[buffer];
 487                 if (!vb)
 488                         continue;
 489
 490                 /* Free MMAP buffers or release USERPTR buffers */
 491                 if (q->memory == VB2_MEMORY_MMAP)
 492                         __vb2_buf_mem_free(vb);
 493                 else if (q->memory == VB2_MEMORY_DMABUF)
 494                         __vb2_buf_dmabuf_put(vb);
 495                 else
 496                         __vb2_buf_userptr_put(vb);
 497         }
 498 }
 499
 500 /*
 501  * __vb2_queue_free() - free buffers at the end of the queue - video memory and
 502  * related information, if no buffers are left return the queue to an
 503  * uninitialized state. Might be called even if the queue has already been freed.
 504  */
 505 static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
 506 {
 507         unsigned int buffer;
 508
 509         lockdep_assert_held(&q->mmap_lock);
 510
 511         /* Call driver-provided cleanup function for each buffer, if provided */
 512         for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
 513              ++buffer) {
 514                 struct vb2_buffer *vb = q->bufs[buffer];
 515
 516                 if (vb && vb->planes[0].mem_priv)
 517                         call_void_vb_qop(vb, buf_cleanup, vb);
 518         }
 519
 520         /* Release video buffer memory */
 521         __vb2_free_mem(q, buffers);
 522
 523 #ifdef CONFIG_VIDEO_ADV_DEBUG
 524         /*
 525          * Check that all the calls were balances during the life-time of this
 526          * queue. If not (or if the debug level is 1 or up), then dump the
 527          * counters to the kernel log.
 528          */
 529         if (q->num_buffers) {
 530                 bool unbalanced = q->cnt_start_streaming != q->cnt_stop_streaming ||
 531                                   q->cnt_prepare_streaming != q->cnt_unprepare_streaming ||
 532                                   q->cnt_wait_prepare != q->cnt_wait_finish;
 533
 534                 if (unbalanced || debug) {
 535                         pr_info("counters for queue %p:%s\n", q,
 536                                 unbalanced ? " UNBALANCED!" : "");
 537                         pr_info("     setup: %u start_streaming: %u stop_streaming: %u\n",
 538                                 q->cnt_queue_setup, q->cnt_start_streaming,
 539                                 q->cnt_stop_streaming);
 540                         pr_info("     prepare_streaming: %u unprepare_streaming: %u\n",
 541                                 q->cnt_prepare_streaming, q->cnt_unprepare_streaming);
 542                         pr_info("     wait_prepare: %u wait_finish: %u\n",
 543                                 q->cnt_wait_prepare, q->cnt_wait_finish);
 544                 }
 545                 q->cnt_queue_setup = 0;
 546                 q->cnt_wait_prepare = 0;
 547                 q->cnt_wait_finish = 0;
 548                 q->cnt_prepare_streaming = 0;
 549                 q->cnt_start_streaming = 0;
 550                 q->cnt_stop_streaming = 0;
 551                 q->cnt_unprepare_streaming = 0;
 552         }
 553         for (buffer = 0; buffer < q->num_buffers; ++buffer) {
 554                 struct vb2_buffer *vb = q->bufs[buffer];
 555                 bool unbalanced = vb->cnt_mem_alloc != vb->cnt_mem_put ||
 556                                   vb->cnt_mem_prepare != vb->cnt_mem_finish ||
 557                                   vb->cnt_mem_get_userptr != vb->cnt_mem_put_userptr ||
 558                                   vb->cnt_mem_attach_dmabuf != vb->cnt_mem_detach_dmabuf ||
 559                                   vb->cnt_mem_map_dmabuf != vb->cnt_mem_unmap_dmabuf ||
 560                                   vb->cnt_buf_queue != vb->cnt_buf_done ||
 561                                   vb->cnt_buf_prepare != vb->cnt_buf_finish ||
 562                                   vb->cnt_buf_init != vb->cnt_buf_cleanup;
 563
 564                 if (unbalanced || debug) {
 565                         pr_info("   counters for queue %p, buffer %d:%s\n",
 566                                 q, buffer, unbalanced ? " UNBALANCED!" : "");
 567                         pr_info("     buf_init: %u buf_cleanup: %u buf_prepare: %u buf_finish: %u\n",
 568                                 vb->cnt_buf_init, vb->cnt_buf_cleanup,
 569                                 vb->cnt_buf_prepare, vb->cnt_buf_finish);
 570                         pr_info("     buf_out_validate: %u buf_queue: %u buf_done: %u buf_request_complete: %u\n",
 571                                 vb->cnt_buf_out_validate, vb->cnt_buf_queue,
 572                                 vb->cnt_buf_done, vb->cnt_buf_request_complete);
 573                         pr_info("     alloc: %u put: %u prepare: %u finish: %u mmap: %u\n",
 574                                 vb->cnt_mem_alloc, vb->cnt_mem_put,
 575                                 vb->cnt_mem_prepare, vb->cnt_mem_finish,
 576                                 vb->cnt_mem_mmap);
 577                         pr_info("     get_userptr: %u put_userptr: %u\n",
 578                                 vb->cnt_mem_get_userptr, vb->cnt_mem_put_userptr);
 579                         pr_info("     attach_dmabuf: %u detach_dmabuf: %u map_dmabuf: %u unmap_dmabuf: %u\n",
 580                                 vb->cnt_mem_attach_dmabuf, vb->cnt_mem_detach_dmabuf,
 581                                 vb->cnt_mem_map_dmabuf, vb->cnt_mem_unmap_dmabuf);
 582                         pr_info("     get_dmabuf: %u num_users: %u vaddr: %u cookie: %u\n",
 583                                 vb->cnt_mem_get_dmabuf,
 584                                 vb->cnt_mem_num_users,
 585                                 vb->cnt_mem_vaddr,
 586                                 vb->cnt_mem_cookie);
 587                 }
 588         }
 589 #endif
 590
 591         /* Free vb2 buffers */
 592         for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
 593              ++buffer) {
 594                 kfree(q->bufs[buffer]);
 595                 q->bufs[buffer] = NULL;
 596         }
 597
 598         q->num_buffers -= buffers;
 599         if (!q->num_buffers) {
 600                 q->memory = VB2_MEMORY_UNKNOWN;
 601                 INIT_LIST_HEAD(&q->queued_list);
 602         }
 603 }
 604
 605 bool vb2_buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb)
 606 {
 607         unsigned int plane;
 608         for (plane = 0; plane < vb->num_planes; ++plane) {
 609                 void *mem_priv = vb->planes[plane].mem_priv;
 610                 /*
 611                  * If num_users() has not been provided, call_memop
 612                  * will return 0, apparently nobody cares about this
 613                  * case anyway. If num_users() returns more than 1,
 614                  * we are not the only user of the plane's memory.
 615                  */
 616                 if (mem_priv && call_memop(vb, num_users, mem_priv) > 1)
 617                         return true;
 618         }
 619         return false;
 620 }
 621 EXPORT_SYMBOL(vb2_buffer_in_use);
 622
 623 /*
 624  * __buffers_in_use() - return true if any buffers on the queue are in use and
 625  * the queue cannot be freed (by the means of REQBUFS(0)) call
 626  */
 627 static bool __buffers_in_use(struct vb2_queue *q)
 628 {
 629         unsigned int buffer;
 630         for (buffer = 0; buffer < q->num_buffers; ++buffer) {
 631                 if (vb2_buffer_in_use(q, q->bufs[buffer]))
 632                         return true;
 633         }
 634         return false;
 635 }
 636
 637 void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb)
 638 {
 639         call_void_bufop(q, fill_user_buffer, q->bufs[index], pb);
 640 }
 641 EXPORT_SYMBOL_GPL(vb2_core_querybuf);
 642
 643 /*
 644  * __verify_userptr_ops() - verify that all memory operations required for
 645  * USERPTR queue type have been provided
 646  */
 647 static int __verify_userptr_ops(struct vb2_queue *q)
 648 {
 649         if (!(q->io_modes & VB2_USERPTR) || !q->mem_ops->get_userptr ||
 650             !q->mem_ops->put_userptr)
 651                 return -EINVAL;
 652
 653         return 0;
 654 }
 655
 656 /*
 657  * __verify_mmap_ops() - verify that all memory operations required for
 658  * MMAP queue type have been provided
 659  */
 660 static int __verify_mmap_ops(struct vb2_queue *q)
 661 {
 662         if (!(q->io_modes & VB2_MMAP) || !q->mem_ops->alloc ||
 663             !q->mem_ops->put || !q->mem_ops->mmap)
 664                 return -EINVAL;
 665
 666         return 0;
 667 }
 668
 669 /*
 670  * __verify_dmabuf_ops() - verify that all memory operations required for
 671  * DMABUF queue type have been provided
 672  */
 673 static int __verify_dmabuf_ops(struct vb2_queue *q)
 674 {
 675         if (!(q->io_modes & VB2_DMABUF) || !q->mem_ops->attach_dmabuf ||
 676             !q->mem_ops->detach_dmabuf  || !q->mem_ops->map_dmabuf ||
 677             !q->mem_ops->unmap_dmabuf)
 678                 return -EINVAL;
 679
 680         return 0;
 681 }
 682
 683 int vb2_verify_memory_type(struct vb2_queue *q,
 684                 enum vb2_memory memory, unsigned int type)
 685 {
 686         if (memory != VB2_MEMORY_MMAP && memory != VB2_MEMORY_USERPTR &&
 687             memory != VB2_MEMORY_DMABUF) {
 688                 dprintk(q, 1, "unsupported memory type\n");
 689                 return -EINVAL;
 690         }
 691
 692         if (type != q->type) {
 693                 dprintk(q, 1, "requested type is incorrect\n");
 694                 return -EINVAL;
 695         }
 696
 697         /*
 698          * Make sure all the required memory ops for given memory type
 699          * are available.
 700          */
 701         if (memory == VB2_MEMORY_MMAP && __verify_mmap_ops(q)) {
 702                 dprintk(q, 1, "MMAP for current setup unsupported\n");
 703                 return -EINVAL;
 704         }
 705
 706         if (memory == VB2_MEMORY_USERPTR && __verify_userptr_ops(q)) {
 707                 dprintk(q, 1, "USERPTR for current setup unsupported\n");
 708                 return -EINVAL;
 709         }
 710
 711         if (memory == VB2_MEMORY_DMABUF && __verify_dmabuf_ops(q)) {
 712                 dprintk(q, 1, "DMABUF for current setup unsupported\n");
 713                 return -EINVAL;
 714         }
 715
 716         /*
 717          * Place the busy tests at the end: -EBUSY can be ignored when
 718          * create_bufs is called with count == 0, but count == 0 should still
 719          * do the memory and type validation.
 720          */
 721         if (vb2_fileio_is_active(q)) {
 722                 dprintk(q, 1, "file io in progress\n");
 723                 return -EBUSY;
 724         }
 725         return 0;
 726 }
 727 EXPORT_SYMBOL(vb2_verify_memory_type);
 728
 729 static void set_queue_coherency(struct vb2_queue *q, bool non_coherent_mem)
 730 {
 731         q->non_coherent_mem = 0;
 732
 733         if (!vb2_queue_allows_cache_hints(q))
 734                 return;
 735         q->non_coherent_mem = non_coherent_mem;
 736 }
 737
 738 static bool verify_coherency_flags(struct vb2_queue *q, bool non_coherent_mem)
 739 {
 740         if (non_coherent_mem != q->non_coherent_mem) {
 741                 dprintk(q, 1, "memory coherency model mismatch\n");
 742                 return false;
 743         }
 744         return true;
 745 }
 746
 747 int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
 748                      unsigned int flags, unsigned int *count)
 749 {
 750         unsigned int num_buffers, allocated_buffers, num_planes = 0;
 751         unsigned plane_sizes[VB2_MAX_PLANES] = { };
 752         bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT;
 753         unsigned int i;
 754         int ret;
 755
 756         if (q->streaming) {
 757                 dprintk(q, 1, "streaming active\n");
 758                 return -EBUSY;
 759         }
 760
 761         if (q->waiting_in_dqbuf && *count) {
 762                 dprintk(q, 1, "another dup()ped fd is waiting for a buffer\n");
 763                 return -EBUSY;
 764         }
 765
 766         if (*count == 0 || q->num_buffers != 0 ||
 767             (q->memory != VB2_MEMORY_UNKNOWN && q->memory != memory) ||
 768             !verify_coherency_flags(q, non_coherent_mem)) {
 769                 /*
 770                  * We already have buffers allocated, so first check if they
 771                  * are not in use and can be freed.
 772                  */
 773                 mutex_lock(&q->mmap_lock);
 774                 if (debug && q->memory == VB2_MEMORY_MMAP &&
 775                     __buffers_in_use(q))
 776                         dprintk(q, 1, "memory in use, orphaning buffers\n");
 777
 778                 /*
 779                  * Call queue_cancel to clean up any buffers in the
 780                  * QUEUED state which is possible if buffers were prepared or
 781                  * queued without ever calling STREAMON.
 782                  */
 783                 __vb2_queue_cancel(q);
 784                 __vb2_queue_free(q, q->num_buffers);
 785                 mutex_unlock(&q->mmap_lock);
 786
 787                 /*
 788                  * In case of REQBUFS(0) return immediately without calling
 789                  * driver's queue_setup() callback and allocating resources.
 790                  */
 791                 if (*count == 0)
 792                         return 0;
 793         }
 794
 795         /*
 796          * Make sure the requested values and current defaults are sane.
 797          */
 798         WARN_ON(q->min_buffers_needed > VB2_MAX_FRAME);
 799         num_buffers = max_t(unsigned int, *count, q->min_buffers_needed);
 800         num_buffers = min_t(unsigned int, num_buffers, VB2_MAX_FRAME);
 801         memset(q->alloc_devs, 0, sizeof(q->alloc_devs));
 802         /*
 803          * Set this now to ensure that drivers see the correct q->memory value
 804          * in the queue_setup op.
 805          */
 806         mutex_lock(&q->mmap_lock);
 807         q->memory = memory;
 808         mutex_unlock(&q->mmap_lock);
 809         set_queue_coherency(q, non_coherent_mem);
 810
 811         /*
 812          * Ask the driver how many buffers and planes per buffer it requires.
 813          * Driver also sets the size and allocator context for each plane.
 814          */
 815         ret = call_qop(q, queue_setup, q, &num_buffers, &num_planes,
 816                        plane_sizes, q->alloc_devs);
 817         if (ret)
 818                 goto error;
 819
 820         /* Check that driver has set sane values */
 821         if (WARN_ON(!num_planes)) {
 822                 ret = -EINVAL;
 823                 goto error;
 824         }
 825
 826         for (i = 0; i < num_planes; i++)
 827                 if (WARN_ON(!plane_sizes[i])) {
 828                         ret = -EINVAL;
 829                         goto error;
 830                 }
 831
 832         /* Finally, allocate buffers and video memory */
 833         allocated_buffers =
 834                 __vb2_queue_alloc(q, memory, num_buffers, num_planes, plane_sizes);
 835         if (allocated_buffers == 0) {
 836                 dprintk(q, 1, "memory allocation failed\n");
 837                 ret = -ENOMEM;
 838                 goto error;
 839         }
 840
 841         /*
 842          * There is no point in continuing if we can't allocate the minimum
 843          * number of buffers needed by this vb2_queue.
 844          */
 845         if (allocated_buffers < q->min_buffers_needed)
 846                 ret = -ENOMEM;
 847
 848         /*
 849          * Check if driver can handle the allocated number of buffers.
 850          */
 851         if (!ret && allocated_buffers < num_buffers) {
 852                 num_buffers = allocated_buffers;
 853                 /*
 854                  * num_planes is set by the previous queue_setup(), but since it
 855                  * signals to queue_setup() whether it is called from create_bufs()
 856                  * vs reqbufs() we zero it here to signal that queue_setup() is
 857                  * called for the reqbufs() case.
 858                  */
 859                 num_planes = 0;
 860
 861                 ret = call_qop(q, queue_setup, q, &num_buffers,
 862                                &num_planes, plane_sizes, q->alloc_devs);
 863
 864                 if (!ret && allocated_buffers < num_buffers)
 865                         ret = -ENOMEM;
 866
 867                 /*
 868                  * Either the driver has accepted a smaller number of buffers,
 869                  * or .queue_setup() returned an error
 870                  */
 871         }
 872
 873         mutex_lock(&q->mmap_lock);
 874         q->num_buffers = allocated_buffers;
 875
 876         if (ret < 0) {
 877                 /*
 878                  * Note: __vb2_queue_free() will subtract 'allocated_buffers'
 879                  * from q->num_buffers and it will reset q->memory to
 880                  * VB2_MEMORY_UNKNOWN.
 881                  */
 882                 __vb2_queue_free(q, allocated_buffers);
 883                 mutex_unlock(&q->mmap_lock);
 884                 return ret;
 885         }
 886         mutex_unlock(&q->mmap_lock);
 887
 888         /*
 889          * Return the number of successfully allocated buffers
 890          * to the userspace.
 891          */
 892         *count = allocated_buffers;
 893         q->waiting_for_buffers = !q->is_output;
 894
 895         return 0;
 896
 897 error:
 898         mutex_lock(&q->mmap_lock);
 899         q->memory = VB2_MEMORY_UNKNOWN;
 900         mutex_unlock(&q->mmap_lock);
 901         return ret;
 902 }
 903 EXPORT_SYMBOL_GPL(vb2_core_reqbufs);
 904
 905 int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
 906                          unsigned int flags, unsigned int *count,
 907                          unsigned int requested_planes,
 908                          const unsigned int requested_sizes[])
 909 {
 910         unsigned int num_planes = 0, num_buffers, allocated_buffers;
 911         unsigned plane_sizes[VB2_MAX_PLANES] = { };
 912         bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT;
 913         bool no_previous_buffers = !q->num_buffers;
 914         int ret;
 915
 916         if (q->num_buffers == VB2_MAX_FRAME) {
 917                 dprintk(q, 1, "maximum number of buffers already allocated\n");
 918                 return -ENOBUFS;
 919         }
 920
 921         if (no_previous_buffers) {
 922                 if (q->waiting_in_dqbuf && *count) {
 923                         dprintk(q, 1, "another dup()ped fd is waiting for a buffer\n");
 924                         return -EBUSY;
 925                 }
 926                 memset(q->alloc_devs, 0, sizeof(q->alloc_devs));
 927                 /*
 928                  * Set this now to ensure that drivers see the correct q->memory
 929                  * value in the queue_setup op.
 930                  */
 931                 mutex_lock(&q->mmap_lock);
 932                 q->memory = memory;
 933                 mutex_unlock(&q->mmap_lock);
 934                 q->waiting_for_buffers = !q->is_output;
 935                 set_queue_coherency(q, non_coherent_mem);
 936         } else {
 937                 if (q->memory != memory) {
 938                         dprintk(q, 1, "memory model mismatch\n");
 939                         return -EINVAL;
 940                 }
 941                 if (!verify_coherency_flags(q, non_coherent_mem))
 942                         return -EINVAL;
 943         }
 944
 945         num_buffers = min(*count, VB2_MAX_FRAME - q->num_buffers);
 946
 947         if (requested_planes && requested_sizes) {
 948                 num_planes = requested_planes;
 949                 memcpy(plane_sizes, requested_sizes, sizeof(plane_sizes));
 950         }
 951
 952         /*
 953          * Ask the driver, whether the requested number of buffers, planes per
 954          * buffer and their sizes are acceptable
 955          */
 956         ret = call_qop(q, queue_setup, q, &num_buffers,
 957                        &num_planes, plane_sizes, q->alloc_devs);
 958         if (ret)
 959                 goto error;
 960
 961         /* Finally, allocate buffers and video memory */
 962         allocated_buffers = __vb2_queue_alloc(q, memory, num_buffers,
 963                                 num_planes, plane_sizes);
 964         if (allocated_buffers == 0) {
 965                 dprintk(q, 1, "memory allocation failed\n");
 966                 ret = -ENOMEM;
 967                 goto error;
 968         }
 969
 970         /*
 971          * Check if driver can handle the so far allocated number of buffers.
 972          */
 973         if (allocated_buffers < num_buffers) {
 974                 num_buffers = allocated_buffers;
 975
 976                 /*
 977                  * q->num_buffers contains the total number of buffers, that the
 978                  * queue driver has set up
 979                  */
 980                 ret = call_qop(q, queue_setup, q, &num_buffers,
 981                                &num_planes, plane_sizes, q->alloc_devs);
 982
 983                 if (!ret && allocated_buffers < num_buffers)
 984                         ret = -ENOMEM;
 985
 986                 /*
 987                  * Either the driver has accepted a smaller number of buffers,
 988                  * or .queue_setup() returned an error
 989                  */
 990         }
 991
 992         mutex_lock(&q->mmap_lock);
 993         q->num_buffers += allocated_buffers;
 994
 995         if (ret < 0) {
 996                 /*
 997                  * Note: __vb2_queue_free() will subtract 'allocated_buffers'
 998                  * from q->num_buffers and it will reset q->memory to
 999                  * VB2_MEMORY_UNKNOWN.
1000                  */
1001                 __vb2_queue_free(q, allocated_buffers);
1002                 mutex_unlock(&q->mmap_lock);
1003                 return -ENOMEM;
1004         }
1005         mutex_unlock(&q->mmap_lock);
1006
1007         /*
1008          * Return the number of successfully allocated buffers
1009          * to the userspace.
1010          */
1011         *count = allocated_buffers;
1012
1013         return 0;
1014
1015 error:
1016         if (no_previous_buffers) {
1017                 mutex_lock(&q->mmap_lock);
1018                 q->memory = VB2_MEMORY_UNKNOWN;
1019                 mutex_unlock(&q->mmap_lock);
1020         }
1021         return ret;
1022 }
1023 EXPORT_SYMBOL_GPL(vb2_core_create_bufs);
1024
1025 void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no)
1026 {
1027         if (plane_no >= vb->num_planes || !vb->planes[plane_no].mem_priv)
1028                 return NULL;
1029
1030         return call_ptr_memop(vaddr, vb, vb->planes[plane_no].mem_priv);
1031
1032 }
1033 EXPORT_SYMBOL_GPL(vb2_plane_vaddr);
1034
1035 void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no)
1036 {
1037         if (plane_no >= vb->num_planes || !vb->planes[plane_no].mem_priv)
1038                 return NULL;
1039
1040         return call_ptr_memop(cookie, vb, vb->planes[plane_no].mem_priv);
1041 }
1042 EXPORT_SYMBOL_GPL(vb2_plane_cookie);
1043
1044 void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state)
1045 {
1046         struct vb2_queue *q = vb->vb2_queue;
1047         unsigned long flags;
1048
1049         if (WARN_ON(vb->state != VB2_BUF_STATE_ACTIVE))
1050                 return;
1051
1052         if (WARN_ON(state != VB2_BUF_STATE_DONE &&
1053                     state != VB2_BUF_STATE_ERROR &&
1054                     state != VB2_BUF_STATE_QUEUED))
1055                 state = VB2_BUF_STATE_ERROR;
1056
1057 #ifdef CONFIG_VIDEO_ADV_DEBUG
1058         /*
1059          * Although this is not a callback, it still does have to balance
1060          * with the buf_queue op. So update this counter manually.
1061          */
1062         vb->cnt_buf_done++;
1063 #endif
1064         dprintk(q, 4, "done processing on buffer %d, state: %s\n",
1065                 vb->index, vb2_state_name(state));
1066
1067         if (state != VB2_BUF_STATE_QUEUED)
1068                 __vb2_buf_mem_finish(vb);
1069
1070         spin_lock_irqsave(&q->done_lock, flags);
1071         if (state == VB2_BUF_STATE_QUEUED) {
1072                 vb->state = VB2_BUF_STATE_QUEUED;
1073         } else {
1074                 /* Add the buffer to the done buffers list */
1075                 list_add_tail(&vb->done_entry, &q->done_list);
1076                 vb->state = state;
1077         }
1078         atomic_dec(&q->owned_by_drv_count);
1079
1080         if (state != VB2_BUF_STATE_QUEUED && vb->req_obj.req) {
1081                 media_request_object_unbind(&vb->req_obj);
1082                 media_request_object_put(&vb->req_obj);
1083         }
1084
1085         spin_unlock_irqrestore(&q->done_lock, flags);
1086
1087         trace_vb2_buf_done(q, vb);
1088
1089         switch (state) {
1090         case VB2_BUF_STATE_QUEUED:
1091                 return;
1092         default:
1093                 /* Inform any processes that may be waiting for buffers */
1094                 wake_up(&q->done_wq);
1095                 break;
1096         }
1097 }
1098 EXPORT_SYMBOL_GPL(vb2_buffer_done);
1099
1100 void vb2_discard_done(struct vb2_queue *q)
1101 {
1102         struct vb2_buffer *vb;
1103         unsigned long flags;
1104
1105         spin_lock_irqsave(&q->done_lock, flags);
1106         list_for_each_entry(vb, &q->done_list, done_entry)
1107                 vb->state = VB2_BUF_STATE_ERROR;
1108         spin_unlock_irqrestore(&q->done_lock, flags);
1109 }
1110 EXPORT_SYMBOL_GPL(vb2_discard_done);
1111
1112 /*
1113  * __prepare_mmap() - prepare an MMAP buffer
1114  */
1115 static int __prepare_mmap(struct vb2_buffer *vb)
1116 {
1117         int ret = 0;
1118
1119         ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
1120                          vb, vb->planes);
1121         return ret ? ret : call_vb_qop(vb, buf_prepare, vb);
1122 }
1123
1124 /*
1125  * __prepare_userptr() - prepare a USERPTR buffer
1126  */
1127 static int __prepare_userptr(struct vb2_buffer *vb)
1128 {
1129         struct vb2_plane planes[VB2_MAX_PLANES];
1130         struct vb2_queue *q = vb->vb2_queue;
1131         void *mem_priv;
1132         unsigned int plane;
1133         int ret = 0;
1134         bool reacquired = vb->planes[0].mem_priv == NULL;
1135
1136         memset(planes, 0, sizeof(planes[0]) * vb->num_planes);
1137         /* Copy relevant information provided by the userspace */
1138         ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
1139                          vb, planes);
1140         if (ret)
1141                 return ret;
1142
1143         for (plane = 0; plane < vb->num_planes; ++plane) {
1144                 /* Skip the plane if already verified */
1145                 if (vb->planes[plane].m.userptr &&
1146                         vb->planes[plane].m.userptr == planes[plane].m.userptr
1147                         && vb->planes[plane].length == planes[plane].length)
1148                         continue;
1149
1150                 dprintk(q, 3, "userspace address for plane %d changed, reacquiring memory\n",
1151                         plane);
1152
1153                 /* Check if the provided plane buffer is large enough */
1154                 if (planes[plane].length < vb->planes[plane].min_length) {
1155                         dprintk(q, 1, "provided buffer size %u is less than setup size %u for plane %d\n",
1156                                                 planes[plane].length,
1157                                                 vb->planes[plane].min_length,
1158                                                 plane);
1159                         ret = -EINVAL;
1160                         goto err;
1161                 }
1162
1163                 /* Release previously acquired memory if present */
1164                 if (vb->planes[plane].mem_priv) {
1165                         if (!reacquired) {
1166                                 reacquired = true;
1167                                 vb->copied_timestamp = 0;
1168                                 call_void_vb_qop(vb, buf_cleanup, vb);
1169                         }
1170                         call_void_memop(vb, put_userptr, vb->planes[plane].mem_priv);
1171                 }
1172
1173                 vb->planes[plane].mem_priv = NULL;
1174                 vb->planes[plane].bytesused = 0;
1175                 vb->planes[plane].length = 0;
1176                 vb->planes[plane].m.userptr = 0;
1177                 vb->planes[plane].data_offset = 0;
1178
1179                 /* Acquire each plane's memory */
1180                 mem_priv = call_ptr_memop(get_userptr,
1181                                           vb,
1182                                           q->alloc_devs[plane] ? : q->dev,
1183                                           planes[plane].m.userptr,
1184                                           planes[plane].length);
1185                 if (IS_ERR(mem_priv)) {
1186                         dprintk(q, 1, "failed acquiring userspace memory for plane %d\n",
1187                                 plane);
1188                         ret = PTR_ERR(mem_priv);
1189                         goto err;
1190                 }
1191                 vb->planes[plane].mem_priv = mem_priv;
1192         }
1193
1194         /*
1195          * Now that everything is in order, copy relevant information
1196          * provided by userspace.
1197          */
1198         for (plane = 0; plane < vb->num_planes; ++plane) {
1199                 vb->planes[plane].bytesused = planes[plane].bytesused;
1200                 vb->planes[plane].length = planes[plane].length;
1201                 vb->planes[plane].m.userptr = planes[plane].m.userptr;
1202                 vb->planes[plane].data_offset = planes[plane].data_offset;
1203         }
1204
1205         if (reacquired) {
1206                 /*
1207                  * One or more planes changed, so we must call buf_init to do
1208                  * the driver-specific initialization on the newly acquired
1209                  * buffer, if provided.
1210                  */
1211                 ret = call_vb_qop(vb, buf_init, vb);
1212                 if (ret) {
1213                         dprintk(q, 1, "buffer initialization failed\n");
1214                         goto err;
1215                 }
1216         }
1217
1218         ret = call_vb_qop(vb, buf_prepare, vb);
1219         if (ret) {
1220                 dprintk(q, 1, "buffer preparation failed\n");
1221                 call_void_vb_qop(vb, buf_cleanup, vb);
1222                 goto err;
1223         }
1224
1225         return 0;
1226 err:
1227         /* In case of errors, release planes that were already acquired */
1228         for (plane = 0; plane < vb->num_planes; ++plane) {
1229                 if (vb->planes[plane].mem_priv)
1230                         call_void_memop(vb, put_userptr,
1231                                 vb->planes[plane].mem_priv);
1232                 vb->planes[plane].mem_priv = NULL;
1233                 vb->planes[plane].m.userptr = 0;
1234                 vb->planes[plane].length = 0;
1235         }
1236
1237         return ret;
1238 }
1239
1240 /*
1241  * __prepare_dmabuf() - prepare a DMABUF buffer
1242  */
1243 static int __prepare_dmabuf(struct vb2_buffer *vb)
1244 {
1245         struct vb2_plane planes[VB2_MAX_PLANES];
1246         struct vb2_queue *q = vb->vb2_queue;
1247         void *mem_priv;
1248         unsigned int plane;
1249         int ret = 0;
1250         bool reacquired = vb->planes[0].mem_priv == NULL;
1251
1252         memset(planes, 0, sizeof(planes[0]) * vb->num_planes);
1253         /* Copy relevant information provided by the userspace */
1254         ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
1255                          vb, planes);
1256         if (ret)
1257                 return ret;
1258
1259         for (plane = 0; plane < vb->num_planes; ++plane) {
1260                 struct dma_buf *dbuf = dma_buf_get(planes[plane].m.fd);
1261
1262                 if (IS_ERR_OR_NULL(dbuf)) {
1263                         dprintk(q, 1, "invalid dmabuf fd for plane %d\n",
1264                                 plane);
1265                         ret = -EINVAL;
1266                         goto err;
1267                 }
1268
1269                 /* use DMABUF size if length is not provided */
1270                 if (planes[plane].length == 0)
1271                         planes[plane].length = dbuf->size;
1272
1273                 if (planes[plane].length < vb->planes[plane].min_length) {
1274                         dprintk(q, 1, "invalid dmabuf length %u for plane %d, minimum length %u\n",
1275                                 planes[plane].length, plane,
1276                                 vb->planes[plane].min_length);
1277                         dma_buf_put(dbuf);
1278                         ret = -EINVAL;
1279                         goto err;
1280                 }
1281
1282                 /* Skip the plane if already verified */
1283                 if (dbuf == vb->planes[plane].dbuf &&
1284                         vb->planes[plane].length == planes[plane].length) {
1285                         dma_buf_put(dbuf);
1286                         continue;
1287                 }
1288
1289                 dprintk(q, 3, "buffer for plane %d changed\n", plane);
1290
1291                 if (!reacquired) {
1292                         reacquired = true;
1293                         vb->copied_timestamp = 0;
1294                         call_void_vb_qop(vb, buf_cleanup, vb);
1295                 }
1296
1297                 /* Release previously acquired memory if present */
1298                 __vb2_plane_dmabuf_put(vb, &vb->planes[plane]);
1299                 vb->planes[plane].bytesused = 0;
1300                 vb->planes[plane].length = 0;
1301                 vb->planes[plane].m.fd = 0;
1302                 vb->planes[plane].data_offset = 0;
1303
1304                 /* Acquire each plane's memory */
1305                 mem_priv = call_ptr_memop(attach_dmabuf,
1306                                           vb,
1307                                           q->alloc_devs[plane] ? : q->dev,
1308                                           dbuf,
1309                                           planes[plane].length);
1310                 if (IS_ERR(mem_priv)) {
1311                         dprintk(q, 1, "failed to attach dmabuf\n");
1312                         ret = PTR_ERR(mem_priv);
1313                         dma_buf_put(dbuf);
1314                         goto err;
1315                 }
1316
1317                 vb->planes[plane].dbuf = dbuf;
1318                 vb->planes[plane].mem_priv = mem_priv;
1319         }
1320
1321         /*
1322          * This pins the buffer(s) with dma_buf_map_attachment()). It's done
1323          * here instead just before the DMA, while queueing the buffer(s) so
1324          * userspace knows sooner rather than later if the dma-buf map fails.
1325          */
1326         for (plane = 0; plane < vb->num_planes; ++plane) {
1327                 if (vb->planes[plane].dbuf_mapped)
1328                         continue;
1329
1330                 ret = call_memop(vb, map_dmabuf, vb->planes[plane].mem_priv);
1331                 if (ret) {
1332                         dprintk(q, 1, "failed to map dmabuf for plane %d\n",
1333                                 plane);
1334                         goto err;
1335                 }
1336                 vb->planes[plane].dbuf_mapped = 1;
1337         }
1338
1339         /*
1340          * Now that everything is in order, copy relevant information
1341          * provided by userspace.
1342          */
1343         for (plane = 0; plane < vb->num_planes; ++plane) {
1344                 vb->planes[plane].bytesused = planes[plane].bytesused;
1345                 vb->planes[plane].length = planes[plane].length;
1346                 vb->planes[plane].m.fd = planes[plane].m.fd;
1347                 vb->planes[plane].data_offset = planes[plane].data_offset;
1348         }
1349
1350         if (reacquired) {
1351                 /*
1352                  * Call driver-specific initialization on the newly acquired buffer,
1353                  * if provided.
1354                  */
1355                 ret = call_vb_qop(vb, buf_init, vb);
1356                 if (ret) {
1357                         dprintk(q, 1, "buffer initialization failed\n");
1358                         goto err;
1359                 }
1360         }
1361
1362         ret = call_vb_qop(vb, buf_prepare, vb);
1363         if (ret) {
1364                 dprintk(q, 1, "buffer preparation failed\n");
1365                 call_void_vb_qop(vb, buf_cleanup, vb);
1366                 goto err;
1367         }
1368
1369         return 0;
1370 err:
1371         /* In case of errors, release planes that were already acquired */
1372         __vb2_buf_dmabuf_put(vb);
1373
1374         return ret;
1375 }
1376
1377 /*
1378  * __enqueue_in_driver() - enqueue a vb2_buffer in driver for processing
1379  */
1380 static void __enqueue_in_driver(struct vb2_buffer *vb)
1381 {
1382         struct vb2_queue *q = vb->vb2_queue;
1383
1384         vb->state = VB2_BUF_STATE_ACTIVE;
1385         atomic_inc(&q->owned_by_drv_count);
1386
1387         trace_vb2_buf_queue(q, vb);
1388
1389         call_void_vb_qop(vb, buf_queue, vb);
1390 }
1391
1392 static int __buf_prepare(struct vb2_buffer *vb)
1393 {
1394         struct vb2_queue *q = vb->vb2_queue;
1395         enum vb2_buffer_state orig_state = vb->state;
1396         int ret;
1397
1398         if (q->error) {
1399                 dprintk(q, 1, "fatal error occurred on queue\n");
1400                 return -EIO;
1401         }
1402
1403         if (vb->prepared)
1404                 return 0;
1405         WARN_ON(vb->synced);
1406
1407         if (q->is_output) {
1408                 ret = call_vb_qop(vb, buf_out_validate, vb);
1409                 if (ret) {
1410                         dprintk(q, 1, "buffer validation failed\n");
1411                         return ret;
1412                 }
1413         }
1414
1415         vb->state = VB2_BUF_STATE_PREPARING;
1416
1417         switch (q->memory) {
1418         case VB2_MEMORY_MMAP:
1419                 ret = __prepare_mmap(vb);
1420                 break;
1421         case VB2_MEMORY_USERPTR:
1422                 ret = __prepare_userptr(vb);
1423                 break;
1424         case VB2_MEMORY_DMABUF:
1425                 ret = __prepare_dmabuf(vb);
1426                 break;
1427         default:
1428                 WARN(1, "Invalid queue type\n");
1429                 ret = -EINVAL;
1430                 break;
1431         }
1432
1433         if (ret) {
1434                 dprintk(q, 1, "buffer preparation failed: %d\n", ret);
1435                 vb->state = orig_state;
1436                 return ret;
1437         }
1438
1439         __vb2_buf_mem_prepare(vb);
1440         vb->prepared = 1;
1441         vb->state = orig_state;
1442
1443         return 0;
1444 }
1445
1446 static int vb2_req_prepare(struct media_request_object *obj)
1447 {
1448         struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);
1449         int ret;
1450
1451         if (WARN_ON(vb->state != VB2_BUF_STATE_IN_REQUEST))
1452                 return -EINVAL;
1453
1454         mutex_lock(vb->vb2_queue->lock);
1455         ret = __buf_prepare(vb);
1456         mutex_unlock(vb->vb2_queue->lock);
1457         return ret;
1458 }
1459
1460 static void __vb2_dqbuf(struct vb2_buffer *vb);
1461
1462 static void vb2_req_unprepare(struct media_request_object *obj)
1463 {
1464         struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);
1465
1466         mutex_lock(vb->vb2_queue->lock);
1467         __vb2_dqbuf(vb);
1468         vb->state = VB2_BUF_STATE_IN_REQUEST;
1469         mutex_unlock(vb->vb2_queue->lock);
1470         WARN_ON(!vb->req_obj.req);
1471 }
1472
1473 int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb,
1474                   struct media_request *req);
1475
1476 static void vb2_req_queue(struct media_request_object *obj)
1477 {
1478         struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);
1479         int err;
1480
1481         mutex_lock(vb->vb2_queue->lock);
1482         /*
1483          * There is no method to propagate an error from vb2_core_qbuf(),
1484          * so if this returns a non-0 value, then WARN.
1485          *
1486          * The only exception is -EIO which is returned if q->error is
1487          * set. We just ignore that, and expect this will be caught the
1488          * next time vb2_req_prepare() is called.
1489          */
1490         err = vb2_core_qbuf(vb->vb2_queue, vb->index, NULL, NULL);
1491         WARN_ON_ONCE(err && err != -EIO);
1492         mutex_unlock(vb->vb2_queue->lock);
1493 }
1494
1495 static void vb2_req_unbind(struct media_request_object *obj)
1496 {
1497         struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);
1498
1499         if (vb->state == VB2_BUF_STATE_IN_REQUEST)
1500                 call_void_bufop(vb->vb2_queue, init_buffer, vb);
1501 }
1502
1503 static void vb2_req_release(struct media_request_object *obj)
1504 {
1505         struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);
1506
1507         if (vb->state == VB2_BUF_STATE_IN_REQUEST) {
1508                 vb->state = VB2_BUF_STATE_DEQUEUED;
1509                 if (vb->request)
1510                         media_request_put(vb->request);
1511                 vb->request = NULL;
1512         }
1513 }
1514
1515 static const struct media_request_object_ops vb2_core_req_ops = {
1516         .prepare = vb2_req_prepare,
1517         .unprepare = vb2_req_unprepare,
1518         .queue = vb2_req_queue,
1519         .unbind = vb2_req_unbind,
1520         .release = vb2_req_release,
1521 };
1522
1523 bool vb2_request_object_is_buffer(struct media_request_object *obj)
1524 {
1525         return obj->ops == &vb2_core_req_ops;
1526 }
1527 EXPORT_SYMBOL_GPL(vb2_request_object_is_buffer);
1528
1529 unsigned int vb2_request_buffer_cnt(struct media_request *req)
1530 {
1531         struct media_request_object *obj;
1532         unsigned long flags;
1533         unsigned int buffer_cnt = 0;
1534
1535         spin_lock_irqsave(&req->lock, flags);
1536         list_for_each_entry(obj, &req->objects, list)
1537                 if (vb2_request_object_is_buffer(obj))
1538                         buffer_cnt++;
1539         spin_unlock_irqrestore(&req->lock, flags);
1540
1541         return buffer_cnt;
1542 }
1543 EXPORT_SYMBOL_GPL(vb2_request_buffer_cnt);
1544
1545 int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb)
1546 {
1547         struct vb2_buffer *vb;
1548         int ret;
1549
1550         vb = q->bufs[index];
1551         if (vb->state != VB2_BUF_STATE_DEQUEUED) {
1552                 dprintk(q, 1, "invalid buffer state %s\n",
1553                         vb2_state_name(vb->state));
1554                 return -EINVAL;
1555         }
1556         if (vb->prepared) {
1557                 dprintk(q, 1, "buffer already prepared\n");
1558                 return -EINVAL;
1559         }
1560
1561         ret = __buf_prepare(vb);
1562         if (ret)
1563                 return ret;
1564
1565         /* Fill buffer information for the userspace */
1566         call_void_bufop(q, fill_user_buffer, vb, pb);
1567
1568         dprintk(q, 2, "prepare of buffer %d succeeded\n", vb->index);
1569
1570         return 0;
1571 }
1572 EXPORT_SYMBOL_GPL(vb2_core_prepare_buf);
1573
1574 /*
1575  * vb2_start_streaming() - Attempt to start streaming.
1576  * @q:          videobuf2 queue
1577  *
1578  * Attempt to start streaming. When this function is called there must be
1579  * at least q->min_buffers_needed buffers queued up (i.e. the minimum
1580  * number of buffers required for the DMA engine to function). If the
1581  * @start_streaming op fails it is supposed to return all the driver-owned
1582  * buffers back to vb2 in state QUEUED. Check if that happened and if
1583  * not warn and reclaim them forcefully.
1584  */
1585 static int vb2_start_streaming(struct vb2_queue *q)
1586 {
1587         struct vb2_buffer *vb;
1588         int ret;
1589
1590         /*
1591          * If any buffers were queued before streamon,
1592          * we can now pass them to driver for processing.
1593          */
1594         list_for_each_entry(vb, &q->queued_list, queued_entry)
1595                 __enqueue_in_driver(vb);
1596
1597         /* Tell the driver to start streaming */
1598         q->start_streaming_called = 1;
1599         ret = call_qop(q, start_streaming, q,
1600                        atomic_read(&q->owned_by_drv_count));
1601         if (!ret)
1602                 return 0;
1603
1604         q->start_streaming_called = 0;
1605
1606         dprintk(q, 1, "driver refused to start streaming\n");
1607         /*
1608          * If you see this warning, then the driver isn't cleaning up properly
1609          * after a failed start_streaming(). See the start_streaming()
1610          * documentation in videobuf2-core.h for more information how buffers
1611          * should be returned to vb2 in start_streaming().
1612          */
1613         if (WARN_ON(atomic_read(&q->owned_by_drv_count))) {
1614                 unsigned i;
1615
1616                 /*
1617                  * Forcefully reclaim buffers if the driver did not
1618                  * correctly return them to vb2.
1619                  */
1620                 for (i = 0; i < q->num_buffers; ++i) {
1621                         vb = q->bufs[i];
1622                         if (vb->state == VB2_BUF_STATE_ACTIVE)
1623                                 vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED);
1624                 }
1625                 /* Must be zero now */
1626                 WARN_ON(atomic_read(&q->owned_by_drv_count));
1627         }
1628         /*
1629          * If done_list is not empty, then start_streaming() didn't call
1630          * vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED) but STATE_ERROR or
1631          * STATE_DONE.
1632          */
1633         WARN_ON(!list_empty(&q->done_list));
1634         return ret;
1635 }
1636
1637 int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb,
1638                   struct media_request *req)
1639 {
1640         struct vb2_buffer *vb;
1641         enum vb2_buffer_state orig_state;
1642         int ret;
1643
1644         if (q->error) {
1645                 dprintk(q, 1, "fatal error occurred on queue\n");
1646                 return -EIO;
1647         }
1648
1649         vb = q->bufs[index];
1650
1651         if (!req && vb->state != VB2_BUF_STATE_IN_REQUEST &&
1652             q->requires_requests) {
1653                 dprintk(q, 1, "qbuf requires a request\n");
1654                 return -EBADR;
1655         }
1656
1657         if ((req && q->uses_qbuf) ||
1658             (!req && vb->state != VB2_BUF_STATE_IN_REQUEST &&
1659              q->uses_requests)) {
1660                 dprintk(q, 1, "queue in wrong mode (qbuf vs requests)\n");
1661                 return -EBUSY;
1662         }
1663
1664         if (req) {
1665                 int ret;
1666
1667                 q->uses_requests = 1;
1668                 if (vb->state != VB2_BUF_STATE_DEQUEUED) {
1669                         dprintk(q, 1, "buffer %d not in dequeued state\n",
1670                                 vb->index);
1671                         return -EINVAL;
1672                 }
1673
1674                 if (q->is_output && !vb->prepared) {
1675                         ret = call_vb_qop(vb, buf_out_validate, vb);
1676                         if (ret) {
1677                                 dprintk(q, 1, "buffer validation failed\n");
1678                                 return ret;
1679                         }
1680                 }
1681
1682                 media_request_object_init(&vb->req_obj);
1683
1684                 /* Make sure the request is in a safe state for updating. */
1685                 ret = media_request_lock_for_update(req);
1686                 if (ret)
1687                         return ret;
1688                 ret = media_request_object_bind(req, &vb2_core_req_ops,
1689                                                 q, true, &vb->req_obj);
1690                 media_request_unlock_for_update(req);
1691                 if (ret)
1692                         return ret;
1693
1694                 vb->state = VB2_BUF_STATE_IN_REQUEST;
1695
1696                 /*
1697                  * Increment the refcount and store the request.
1698                  * The request refcount is decremented again when the
1699                  * buffer is dequeued. This is to prevent vb2_buffer_done()
1700                  * from freeing the request from interrupt context, which can
1701                  * happen if the application closed the request fd after
1702                  * queueing the request.
1703                  */
1704                 media_request_get(req);
1705                 vb->request = req;
1706
1707                 /* Fill buffer information for the userspace */
1708                 if (pb) {
1709                         call_void_bufop(q, copy_timestamp, vb, pb);
1710                         call_void_bufop(q, fill_user_buffer, vb, pb);
1711                 }
1712
1713                 dprintk(q, 2, "qbuf of buffer %d succeeded\n", vb->index);
1714                 return 0;
1715         }
1716
1717         if (vb->state != VB2_BUF_STATE_IN_REQUEST)
1718                 q->uses_qbuf = 1;
1719
1720         switch (vb->state) {
1721         case VB2_BUF_STATE_DEQUEUED:
1722         case VB2_BUF_STATE_IN_REQUEST:
1723                 if (!vb->prepared) {
1724                         ret = __buf_prepare(vb);
1725                         if (ret)
1726                                 return ret;
1727                 }
1728                 break;
1729         case VB2_BUF_STATE_PREPARING:
1730                 dprintk(q, 1, "buffer still being prepared\n");
1731                 return -EINVAL;
1732         default:
1733                 dprintk(q, 1, "invalid buffer state %s\n",
1734                         vb2_state_name(vb->state));
1735                 return -EINVAL;
1736         }
1737
1738         /*
1739          * Add to the queued buffers list, a buffer will stay on it until
1740          * dequeued in dqbuf.
1741          */
1742         orig_state = vb->state;
1743         list_add_tail(&vb->queued_entry, &q->queued_list);
1744         q->queued_count++;
1745         q->waiting_for_buffers = false;
1746         vb->state = VB2_BUF_STATE_QUEUED;
1747
1748         if (pb)
1749                 call_void_bufop(q, copy_timestamp, vb, pb);
1750
1751         trace_vb2_qbuf(q, vb);
1752
1753         /*
1754          * If already streaming, give the buffer to driver for processing.
1755          * If not, the buffer will be given to driver on next streamon.
1756          */
1757         if (q->start_streaming_called)
1758                 __enqueue_in_driver(vb);
1759
1760         /* Fill buffer information for the userspace */
1761         if (pb)
1762                 call_void_bufop(q, fill_user_buffer, vb, pb);
1763
1764         /*
1765          * If streamon has been called, and we haven't yet called
1766          * start_streaming() since not enough buffers were queued, and
1767          * we now have reached the minimum number of queued buffers,
1768          * then we can finally call start_streaming().
1769          */
1770         if (q->streaming && !q->start_streaming_called &&
1771             q->queued_count >= q->min_buffers_needed) {
1772                 ret = vb2_start_streaming(q);
1773                 if (ret) {
1774                         /*
1775                          * Since vb2_core_qbuf will return with an error,
1776                          * we should return it to state DEQUEUED since
1777                          * the error indicates that the buffer wasn't queued.
1778                          */
1779                         list_del(&vb->queued_entry);
1780                         q->queued_count--;
1781                         vb->state = orig_state;
1782                         return ret;
1783                 }
1784         }
1785
1786         dprintk(q, 2, "qbuf of buffer %d succeeded\n", vb->index);
1787         return 0;
1788 }
1789 EXPORT_SYMBOL_GPL(vb2_core_qbuf);
1790
1791 /*
1792  * __vb2_wait_for_done_vb() - wait for a buffer to become available
1793  * for dequeuing
1794  *
1795  * Will sleep if required for nonblocking == false.
1796  */
1797 static int __vb2_wait_for_done_vb(struct vb2_queue *q, int nonblocking)
1798 {
1799         /*
1800          * All operations on vb_done_list are performed under done_lock
1801          * spinlock protection. However, buffers may be removed from
1802          * it and returned to userspace only while holding both driver's
1803          * lock and the done_lock spinlock. Thus we can be sure that as
1804          * long as we hold the driver's lock, the list will remain not
1805          * empty if list_empty() check succeeds.
1806          */
1807
1808         for (;;) {
1809                 int ret;
1810
1811                 if (q->waiting_in_dqbuf) {
1812                         dprintk(q, 1, "another dup()ped fd is waiting for a buffer\n");
1813                         return -EBUSY;
1814                 }
1815
1816                 if (!q->streaming) {
1817                         dprintk(q, 1, "streaming off, will not wait for buffers\n");
1818                         return -EINVAL;
1819                 }
1820
1821                 if (q->error) {
1822                         dprintk(q, 1, "Queue in error state, will not wait for buffers\n");
1823                         return -EIO;
1824                 }
1825
1826                 if (q->last_buffer_dequeued) {
1827                         dprintk(q, 3, "last buffer dequeued already, will not wait for buffers\n");
1828                         return -EPIPE;
1829                 }
1830
1831                 if (!list_empty(&q->done_list)) {
1832                         /*
1833                          * Found a buffer that we were waiting for.
1834                          */
1835                         break;
1836                 }
1837
1838                 if (nonblocking) {
1839                         dprintk(q, 3, "nonblocking and no buffers to dequeue, will not wait\n");
1840                         return -EAGAIN;
1841                 }
1842
1843                 q->waiting_in_dqbuf = 1;
1844                 /*
1845                  * We are streaming and blocking, wait for another buffer to
1846                  * become ready or for streamoff. Driver's lock is released to
1847                  * allow streamoff or qbuf to be called while waiting.
1848                  */
1849                 call_void_qop(q, wait_prepare, q);
1850
1851                 /*
1852                  * All locks have been released, it is safe to sleep now.
1853                  */
1854                 dprintk(q, 3, "will sleep waiting for buffers\n");
1855                 ret = wait_event_interruptible(q->done_wq,
1856                                 !list_empty(&q->done_list) || !q->streaming ||
1857                                 q->error);
1858
1859                 /*
1860                  * We need to reevaluate both conditions again after reacquiring
1861                  * the locks or return an error if one occurred.
1862                  */
1863                 call_void_qop(q, wait_finish, q);
1864                 q->waiting_in_dqbuf = 0;
1865                 if (ret) {
1866                         dprintk(q, 1, "sleep was interrupted\n");
1867                         return ret;
1868                 }
1869         }
1870         return 0;
1871 }
1872
1873 /*
1874  * __vb2_get_done_vb() - get a buffer ready for dequeuing
1875  *
1876  * Will sleep if required for nonblocking == false.
1877  */
1878 static int __vb2_get_done_vb(struct vb2_queue *q, struct vb2_buffer **vb,
1879                              void *pb, int nonblocking)
1880 {
1881         unsigned long flags;
1882         int ret = 0;
1883
1884         /*
1885          * Wait for at least one buffer to become available on the done_list.
1886          */
1887         ret = __vb2_wait_for_done_vb(q, nonblocking);
1888         if (ret)
1889                 return ret;
1890
1891         /*
1892          * Driver's lock has been held since we last verified that done_list
1893          * is not empty, so no need for another list_empty(done_list) check.
1894          */
1895         spin_lock_irqsave(&q->done_lock, flags);
1896         *vb = list_first_entry(&q->done_list, struct vb2_buffer, done_entry);
1897         /*
1898          * Only remove the buffer from done_list if all planes can be
1899          * handled. Some cases such as V4L2 file I/O and DVB have pb
1900          * == NULL; skip the check then as there's nothing to verify.
1901          */
1902         if (pb)
1903                 ret = call_bufop(q, verify_planes_array, *vb, pb);
1904         if (!ret)
1905                 list_del(&(*vb)->done_entry);
1906         spin_unlock_irqrestore(&q->done_lock, flags);
1907
1908         return ret;
1909 }
1910
1911 int vb2_wait_for_all_buffers(struct vb2_queue *q)
1912 {
1913         if (!q->streaming) {
1914                 dprintk(q, 1, "streaming off, will not wait for buffers\n");
1915                 return -EINVAL;
1916         }
1917
1918         if (q->start_streaming_called)
1919                 wait_event(q->done_wq, !atomic_read(&q->owned_by_drv_count));
1920         return 0;
1921 }
1922 EXPORT_SYMBOL_GPL(vb2_wait_for_all_buffers);
1923
1924 /*
1925  * __vb2_dqbuf() - bring back the buffer to the DEQUEUED state
1926  */
1927 static void __vb2_dqbuf(struct vb2_buffer *vb)
1928 {
1929         struct vb2_queue *q = vb->vb2_queue;
1930
1931         /* nothing to do if the buffer is already dequeued */
1932         if (vb->state == VB2_BUF_STATE_DEQUEUED)
1933                 return;
1934
1935         vb->state = VB2_BUF_STATE_DEQUEUED;
1936
1937         call_void_bufop(q, init_buffer, vb);
1938 }
1939
1940 int vb2_core_dqbuf(struct vb2_queue *q, unsigned int *pindex, void *pb,
1941                    bool nonblocking)
1942 {
1943         struct vb2_buffer *vb = NULL;
1944         int ret;
1945
1946         ret = __vb2_get_done_vb(q, &vb, pb, nonblocking);
1947         if (ret < 0)
1948                 return ret;
1949
1950         switch (vb->state) {
1951         case VB2_BUF_STATE_DONE:
1952                 dprintk(q, 3, "returning done buffer\n");
1953                 break;
1954         case VB2_BUF_STATE_ERROR:
1955                 dprintk(q, 3, "returning done buffer with errors\n");
1956                 break;
1957         default:
1958                 dprintk(q, 1, "invalid buffer state %s\n",
1959                         vb2_state_name(vb->state));
1960                 return -EINVAL;
1961         }
1962
1963         call_void_vb_qop(vb, buf_finish, vb);
1964         vb->prepared = 0;
1965
1966         if (pindex)
1967                 *pindex = vb->index;
1968
1969         /* Fill buffer information for the userspace */
1970         if (pb)
1971                 call_void_bufop(q, fill_user_buffer, vb, pb);
1972
1973         /* Remove from vb2 queue */
1974         list_del(&vb->queued_entry);
1975         q->queued_count--;
1976
1977         trace_vb2_dqbuf(q, vb);
1978
1979         /* go back to dequeued state */
1980         __vb2_dqbuf(vb);
1981
1982         if (WARN_ON(vb->req_obj.req)) {
1983                 media_request_object_unbind(&vb->req_obj);
1984                 media_request_object_put(&vb->req_obj);
1985         }
1986         if (vb->request)
1987                 media_request_put(vb->request);
1988         vb->request = NULL;
1989
1990         dprintk(q, 2, "dqbuf of buffer %d, state: %s\n",
1991                 vb->index, vb2_state_name(vb->state));
1992
1993         return 0;
1994
1995 }
1996 EXPORT_SYMBOL_GPL(vb2_core_dqbuf);
1997
1998 /*
1999  * __vb2_queue_cancel() - cancel and stop (pause) streaming
2000  *
2001  * Removes all queued buffers from driver's queue and all buffers queued by
2002  * userspace from vb2's queue. Returns to state after reqbufs.
2003  */
2004 static void __vb2_queue_cancel(struct vb2_queue *q)
2005 {
2006         unsigned int i;
2007
2008         /*
2009          * Tell driver to stop all transactions and release all queued
2010          * buffers.
2011          */
2012         if (q->start_streaming_called)
2013                 call_void_qop(q, stop_streaming, q);
2014
2015         if (q->streaming)
2016                 call_void_qop(q, unprepare_streaming, q);
2017
2018         /*
2019          * If you see this warning, then the driver isn't cleaning up properly
2020          * in stop_streaming(). See the stop_streaming() documentation in
2021          * videobuf2-core.h for more information how buffers should be returned
2022          * to vb2 in stop_streaming().
2023          */
2024         if (WARN_ON(atomic_read(&q->owned_by_drv_count))) {
2025                 for (i = 0; i < q->num_buffers; ++i)
2026                         if (q->bufs[i]->state == VB2_BUF_STATE_ACTIVE) {
2027                                 pr_warn("driver bug: stop_streaming operation is leaving buf %p in active state\n",
2028                                         q->bufs[i]);
2029                                 vb2_buffer_done(q->bufs[i], VB2_BUF_STATE_ERROR);
2030                         }
2031                 /* Must be zero now */
2032                 WARN_ON(atomic_read(&q->owned_by_drv_count));
2033         }
2034
2035         q->streaming = 0;
2036         q->start_streaming_called = 0;
2037         q->queued_count = 0;
2038         q->error = 0;
2039         q->uses_requests = 0;
2040         q->uses_qbuf = 0;
2041
2042         /*
2043          * Remove all buffers from vb2's list...
2044          */
2045         INIT_LIST_HEAD(&q->queued_list);
2046         /*
2047          * ...and done list; userspace will not receive any buffers it
2048          * has not already dequeued before initiating cancel.
2049          */
2050         INIT_LIST_HEAD(&q->done_list);
2051         atomic_set(&q->owned_by_drv_count, 0);
2052         wake_up_all(&q->done_wq);
2053
2054         /*
2055          * Reinitialize all buffers for next use.
2056          * Make sure to call buf_finish for any queued buffers. Normally
2057          * that's done in dqbuf, but that's not going to happen when we
2058          * cancel the whole queue. Note: this code belongs here, not in
2059          * __vb2_dqbuf() since in vb2_core_dqbuf() there is a critical
2060          * call to __fill_user_buffer() after buf_finish(). That order can't
2061          * be changed, so we can't move the buf_finish() to __vb2_dqbuf().
2062          */
2063         for (i = 0; i < q->num_buffers; ++i) {
2064                 struct vb2_buffer *vb = q->bufs[i];
2065                 struct media_request *req = vb->req_obj.req;
2066
2067                 /*
2068                  * If a request is associated with this buffer, then
2069                  * call buf_request_cancel() to give the driver to complete()
2070                  * related request objects. Otherwise those objects would
2071                  * never complete.
2072                  */
2073                 if (req) {
2074                         enum media_request_state state;
2075                         unsigned long flags;
2076
2077                         spin_lock_irqsave(&req->lock, flags);
2078                         state = req->state;
2079                         spin_unlock_irqrestore(&req->lock, flags);
2080
2081                         if (state == MEDIA_REQUEST_STATE_QUEUED)
2082                                 call_void_vb_qop(vb, buf_request_complete, vb);
2083                 }
2084
2085                 __vb2_buf_mem_finish(vb);
2086
2087                 if (vb->prepared) {
2088                         call_void_vb_qop(vb, buf_finish, vb);
2089                         vb->prepared = 0;
2090                 }
2091                 __vb2_dqbuf(vb);
2092
2093                 if (vb->req_obj.req) {
2094                         media_request_object_unbind(&vb->req_obj);
2095                         media_request_object_put(&vb->req_obj);
2096                 }
2097                 if (vb->request)
2098                         media_request_put(vb->request);
2099                 vb->request = NULL;
2100                 vb->copied_timestamp = 0;
2101         }
2102 }
2103
2104 int vb2_core_streamon(struct vb2_queue *q, unsigned int type)
2105 {
2106         int ret;
2107
2108         if (type != q->type) {
2109                 dprintk(q, 1, "invalid stream type\n");
2110                 return -EINVAL;
2111         }
2112
2113         if (q->streaming) {
2114                 dprintk(q, 3, "already streaming\n");
2115                 return 0;
2116         }
2117
2118         if (!q->num_buffers) {
2119                 dprintk(q, 1, "no buffers have been allocated\n");
2120                 return -EINVAL;
2121         }
2122
2123         if (q->num_buffers < q->min_buffers_needed) {
2124                 dprintk(q, 1, "need at least %u allocated buffers\n",
2125                                 q->min_buffers_needed);
2126                 return -EINVAL;
2127         }
2128
2129         ret = call_qop(q, prepare_streaming, q);
2130         if (ret)
2131                 return ret;
2132
2133         /*
2134          * Tell driver to start streaming provided sufficient buffers
2135          * are available.
2136          */
2137         if (q->queued_count >= q->min_buffers_needed) {
2138                 ret = vb2_start_streaming(q);
2139                 if (ret)
2140                         goto unprepare;
2141         }
2142
2143         q->streaming = 1;
2144
2145         dprintk(q, 3, "successful\n");
2146         return 0;
2147
2148 unprepare:
2149         call_void_qop(q, unprepare_streaming, q);
2150         return ret;
2151 }
2152 EXPORT_SYMBOL_GPL(vb2_core_streamon);
2153
2154 void vb2_queue_error(struct vb2_queue *q)
2155 {
2156         q->error = 1;
2157
2158         wake_up_all(&q->done_wq);
2159 }
2160 EXPORT_SYMBOL_GPL(vb2_queue_error);
2161
2162 int vb2_core_streamoff(struct vb2_queue *q, unsigned int type)
2163 {
2164         if (type != q->type) {
2165                 dprintk(q, 1, "invalid stream type\n");
2166                 return -EINVAL;
2167         }
2168
2169         /*
2170          * Cancel will pause streaming and remove all buffers from the driver
2171          * and vb2, effectively returning control over them to userspace.
2172          *
2173          * Note that we do this even if q->streaming == 0: if you prepare or
2174          * queue buffers, and then call streamoff without ever having called
2175          * streamon, you would still expect those buffers to be returned to
2176          * their normal dequeued state.
2177          */
2178         __vb2_queue_cancel(q);
2179         q->waiting_for_buffers = !q->is_output;
2180         q->last_buffer_dequeued = false;
2181
2182         dprintk(q, 3, "successful\n");
2183         return 0;
2184 }
2185 EXPORT_SYMBOL_GPL(vb2_core_streamoff);
2186
2187 /*
2188  * __find_plane_by_offset() - find plane associated with the given offset off
2189  */
2190 static int __find_plane_by_offset(struct vb2_queue *q, unsigned long off,
2191                         unsigned int *_buffer, unsigned int *_plane)
2192 {
2193         struct vb2_buffer *vb;
2194         unsigned int buffer, plane;
2195
2196         /*
2197          * Sanity checks to ensure the lock is held, MEMORY_MMAP is
2198          * used and fileio isn't active.
2199          */
2200         lockdep_assert_held(&q->mmap_lock);
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 (vb2_fileio_is_active(q)) {
2208                 dprintk(q, 1, "file io in progress\n");
2209                 return -EBUSY;
2210         }
2211
2212         /*
2213          * Go over all buffers and their planes, comparing the given offset
2214          * with an offset assigned to each plane. If a match is found,
2215          * return its buffer and plane numbers.
2216          */
2217         for (buffer = 0; buffer < q->num_buffers; ++buffer) {
2218                 vb = q->bufs[buffer];
2219
2220                 for (plane = 0; plane < vb->num_planes; ++plane) {
2221                         if (vb->planes[plane].m.offset == off) {
2222                                 *_buffer = buffer;
2223                                 *_plane = plane;
2224                                 return 0;
2225                         }
2226                 }
2227         }
2228
2229         return -EINVAL;
2230 }
2231
2232 int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
2233                 unsigned int index, unsigned int plane, unsigned int flags)
2234 {
2235         struct vb2_buffer *vb = NULL;
2236         struct vb2_plane *vb_plane;
2237         int ret;
2238         struct dma_buf *dbuf;
2239
2240         if (q->memory != VB2_MEMORY_MMAP) {
2241                 dprintk(q, 1, "queue is not currently set up for mmap\n");
2242                 return -EINVAL;
2243         }
2244
2245         if (!q->mem_ops->get_dmabuf) {
2246                 dprintk(q, 1, "queue does not support DMA buffer exporting\n");
2247                 return -EINVAL;
2248         }
2249
2250         if (flags & ~(O_CLOEXEC | O_ACCMODE)) {
2251                 dprintk(q, 1, "queue does support only O_CLOEXEC and access mode flags\n");
2252                 return -EINVAL;
2253         }
2254
2255         if (type != q->type) {
2256                 dprintk(q, 1, "invalid buffer type\n");
2257                 return -EINVAL;
2258         }
2259
2260         if (index >= q->num_buffers) {
2261                 dprintk(q, 1, "buffer index out of range\n");
2262                 return -EINVAL;
2263         }
2264
2265         vb = q->bufs[index];
2266
2267         if (plane >= vb->num_planes) {
2268                 dprintk(q, 1, "buffer plane out of range\n");
2269                 return -EINVAL;
2270         }
2271
2272         if (vb2_fileio_is_active(q)) {
2273                 dprintk(q, 1, "expbuf: file io in progress\n");
2274                 return -EBUSY;
2275         }
2276
2277         vb_plane = &vb->planes[plane];
2278
2279         dbuf = call_ptr_memop(get_dmabuf,
2280                               vb,
2281                               vb_plane->mem_priv,
2282                               flags & O_ACCMODE);
2283         if (IS_ERR_OR_NULL(dbuf)) {
2284                 dprintk(q, 1, "failed to export buffer %d, plane %d\n",
2285                         index, plane);
2286                 return -EINVAL;
2287         }
2288
2289         ret = dma_buf_fd(dbuf, flags & ~O_ACCMODE);
2290         if (ret < 0) {
2291                 dprintk(q, 3, "buffer %d, plane %d failed to export (%d)\n",
2292                         index, plane, ret);
2293                 dma_buf_put(dbuf);
2294                 return ret;
2295         }
2296
2297         dprintk(q, 3, "buffer %d, plane %d exported as %d descriptor\n",
2298                 index, plane, ret);
2299         *fd = ret;
2300
2301         return 0;
2302 }
2303 EXPORT_SYMBOL_GPL(vb2_core_expbuf);
2304
2305 int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma)
2306 {
2307         unsigned long off = vma->vm_pgoff << PAGE_SHIFT;
2308         struct vb2_buffer *vb;
2309         unsigned int buffer = 0, plane = 0;
2310         int ret;
2311         unsigned long length;
2312
2313         /*
2314          * Check memory area access mode.
2315          */
2316         if (!(vma->vm_flags & VM_SHARED)) {
2317                 dprintk(q, 1, "invalid vma flags, VM_SHARED needed\n");
2318                 return -EINVAL;
2319         }
2320         if (q->is_output) {
2321                 if (!(vma->vm_flags & VM_WRITE)) {
2322                         dprintk(q, 1, "invalid vma flags, VM_WRITE needed\n");
2323                         return -EINVAL;
2324                 }
2325         } else {
2326                 if (!(vma->vm_flags & VM_READ)) {
2327                         dprintk(q, 1, "invalid vma flags, VM_READ needed\n");
2328                         return -EINVAL;
2329                 }
2330         }
2331
2332         mutex_lock(&q->mmap_lock);
2333
2334         /*
2335          * Find the plane corresponding to the offset passed by userspace. This
2336          * will return an error if not MEMORY_MMAP or file I/O is in progress.
2337          */
2338         ret = __find_plane_by_offset(q, off, &buffer, &plane);
2339         if (ret)
2340                 goto unlock;
2341
2342         vb = q->bufs[buffer];
2343
2344         /*
2345          * MMAP requires page_aligned buffers.
2346          * The buffer length was page_aligned at __vb2_buf_mem_alloc(),
2347          * so, we need to do the same here.
2348          */
2349         length = PAGE_ALIGN(vb->planes[plane].length);
2350         if (length < (vma->vm_end - vma->vm_start)) {
2351                 dprintk(q, 1,
2352                         "MMAP invalid, as it would overflow buffer length\n");
2353                 ret = -EINVAL;
2354                 goto unlock;
2355         }
2356
2357         /*
2358          * vm_pgoff is treated in V4L2 API as a 'cookie' to select a buffer,
2359          * not as a in-buffer offset. We always want to mmap a whole buffer
2360          * from its beginning.
2361          */
2362         vma->vm_pgoff = 0;
2363
2364         ret = call_memop(vb, mmap, vb->planes[plane].mem_priv, vma);
2365
2366 unlock:
2367         mutex_unlock(&q->mmap_lock);
2368         if (ret)
2369                 return ret;
2370
2371         dprintk(q, 3, "buffer %d, plane %d successfully mapped\n", buffer, plane);
2372         return 0;
2373 }
2374 EXPORT_SYMBOL_GPL(vb2_mmap);
2375
2376 #ifndef CONFIG_MMU
2377 unsigned long vb2_get_unmapped_area(struct vb2_queue *q,
2378                                     unsigned long addr,
2379                                     unsigned long len,
2380                                     unsigned long pgoff,
2381                                     unsigned long flags)
2382 {
2383         unsigned long off = pgoff << PAGE_SHIFT;
2384         struct vb2_buffer *vb;
2385         unsigned int buffer, plane;
2386         void *vaddr;
2387         int ret;
2388
2389         mutex_lock(&q->mmap_lock);
2390
2391         /*
2392          * Find the plane corresponding to the offset passed by userspace. This
2393          * will return an error if not MEMORY_MMAP or file I/O is in progress.
2394          */
2395         ret = __find_plane_by_offset(q, off, &buffer, &plane);
2396         if (ret)
2397                 goto unlock;
2398
2399         vb = q->bufs[buffer];
2400
2401         vaddr = vb2_plane_vaddr(vb, plane);
2402         mutex_unlock(&q->mmap_lock);
2403         return vaddr ? (unsigned long)vaddr : -EINVAL;
2404
2405 unlock:
2406         mutex_unlock(&q->mmap_lock);
2407         return ret;
2408 }
2409 EXPORT_SYMBOL_GPL(vb2_get_unmapped_area);
2410 #endif
2411
2412 int vb2_core_queue_init(struct vb2_queue *q)
2413 {
2414         /*
2415          * Sanity check
2416          */
2417         if (WARN_ON(!q)                   ||
2418             WARN_ON(!q->ops)              ||
2419             WARN_ON(!q->mem_ops)          ||
2420             WARN_ON(!q->type)             ||
2421             WARN_ON(!q->io_modes)         ||
2422             WARN_ON(!q->ops->queue_setup) ||
2423             WARN_ON(!q->ops->buf_queue))
2424                 return -EINVAL;
2425
2426         if (WARN_ON(q->requires_requests && !q->supports_requests))
2427                 return -EINVAL;
2428
2429         /*
2430          * This combination is not allowed since a non-zero value of
2431          * q->min_buffers_needed can cause vb2_core_qbuf() to fail if
2432          * it has to call start_streaming(), and the Request API expects
2433          * that queueing a request (and thus queueing a buffer contained
2434          * in that request) will always succeed. There is no method of
2435          * propagating an error back to userspace.
2436          */
2437         if (WARN_ON(q->supports_requests && q->min_buffers_needed))
2438                 return -EINVAL;
2439
2440         INIT_LIST_HEAD(&q->queued_list);
2441         INIT_LIST_HEAD(&q->done_list);
2442         spin_lock_init(&q->done_lock);
2443         mutex_init(&q->mmap_lock);
2444         init_waitqueue_head(&q->done_wq);
2445
2446         q->memory = VB2_MEMORY_UNKNOWN;
2447
2448         if (q->buf_struct_size == 0)
2449                 q->buf_struct_size = sizeof(struct vb2_buffer);
2450
2451         if (q->bidirectional)
2452                 q->dma_dir = DMA_BIDIRECTIONAL;
2453         else
2454                 q->dma_dir = q->is_output ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
2455
2456         if (q->name[0] == '\0')
2457                 snprintf(q->name, sizeof(q->name), "%s-%p",
2458                          q->is_output ? "out" : "cap", q);
2459
2460         return 0;
2461 }
2462 EXPORT_SYMBOL_GPL(vb2_core_queue_init);
2463
2464 static int __vb2_init_fileio(struct vb2_queue *q, int read);
2465 static int __vb2_cleanup_fileio(struct vb2_queue *q);
2466 void vb2_core_queue_release(struct vb2_queue *q)
2467 {
2468         __vb2_cleanup_fileio(q);
2469         __vb2_queue_cancel(q);
2470         mutex_lock(&q->mmap_lock);
2471         __vb2_queue_free(q, q->num_buffers);
2472         mutex_unlock(&q->mmap_lock);
2473 }
2474 EXPORT_SYMBOL_GPL(vb2_core_queue_release);
2475
2476 __poll_t vb2_core_poll(struct vb2_queue *q, struct file *file,
2477                 poll_table *wait)
2478 {
2479         __poll_t req_events = poll_requested_events(wait);
2480         struct vb2_buffer *vb = NULL;
2481         unsigned long flags;
2482
2483         /*
2484          * poll_wait() MUST be called on the first invocation on all the
2485          * potential queues of interest, even if we are not interested in their
2486          * events during this first call. Failure to do so will result in
2487          * queue's events to be ignored because the poll_table won't be capable
2488          * of adding new wait queues thereafter.
2489          */
2490         poll_wait(file, &q->done_wq, wait);
2491
2492         if (!q->is_output && !(req_events & (EPOLLIN | EPOLLRDNORM)))
2493                 return 0;
2494         if (q->is_output && !(req_events & (EPOLLOUT | EPOLLWRNORM)))
2495                 return 0;
2496
2497         /*
2498          * Start file I/O emulator only if streaming API has not been used yet.
2499          */
2500         if (q->num_buffers == 0 && !vb2_fileio_is_active(q)) {
2501                 if (!q->is_output && (q->io_modes & VB2_READ) &&
2502                                 (req_events & (EPOLLIN | EPOLLRDNORM))) {
2503                         if (__vb2_init_fileio(q, 1))
2504                                 return EPOLLERR;
2505                 }
2506                 if (q->is_output && (q->io_modes & VB2_WRITE) &&
2507                                 (req_events & (EPOLLOUT | EPOLLWRNORM))) {
2508                         if (__vb2_init_fileio(q, 0))
2509                                 return EPOLLERR;
2510                         /*
2511                          * Write to OUTPUT queue can be done immediately.
2512                          */
2513                         return EPOLLOUT | EPOLLWRNORM;
2514                 }
2515         }
2516
2517         /*
2518          * There is nothing to wait for if the queue isn't streaming, or if the
2519          * error flag is set.
2520          */
2521         if (!vb2_is_streaming(q) || q->error)
2522                 return EPOLLERR;
2523
2524         /*
2525          * If this quirk is set and QBUF hasn't been called yet then
2526          * return EPOLLERR as well. This only affects capture queues, output
2527          * queues will always initialize waiting_for_buffers to false.
2528          * This quirk is set by V4L2 for backwards compatibility reasons.
2529          */
2530         if (q->quirk_poll_must_check_waiting_for_buffers &&
2531             q->waiting_for_buffers && (req_events & (EPOLLIN | EPOLLRDNORM)))
2532                 return EPOLLERR;
2533
2534         /*
2535          * For output streams you can call write() as long as there are fewer
2536          * buffers queued than there are buffers available.
2537          */
2538         if (q->is_output && q->fileio && q->queued_count < q->num_buffers)
2539                 return EPOLLOUT | EPOLLWRNORM;
2540
2541         if (list_empty(&q->done_list)) {
2542                 /*
2543                  * If the last buffer was dequeued from a capture queue,
2544                  * return immediately. DQBUF will return -EPIPE.
2545                  */
2546                 if (q->last_buffer_dequeued)
2547                         return EPOLLIN | EPOLLRDNORM;
2548         }
2549
2550         /*
2551          * Take first buffer available for dequeuing.
2552          */
2553         spin_lock_irqsave(&q->done_lock, flags);
2554         if (!list_empty(&q->done_list))
2555                 vb = list_first_entry(&q->done_list, struct vb2_buffer,
2556                                         done_entry);
2557         spin_unlock_irqrestore(&q->done_lock, flags);
2558
2559         if (vb && (vb->state == VB2_BUF_STATE_DONE
2560                         || vb->state == VB2_BUF_STATE_ERROR)) {
2561                 return (q->is_output) ?
2562                                 EPOLLOUT | EPOLLWRNORM :
2563                                 EPOLLIN | EPOLLRDNORM;
2564         }
2565         return 0;
2566 }
2567 EXPORT_SYMBOL_GPL(vb2_core_poll);
2568
2569 /*
2570  * struct vb2_fileio_buf - buffer context used by file io emulator
2571  *
2572  * vb2 provides a compatibility layer and emulator of file io (read and
2573  * write) calls on top of streaming API. This structure is used for
2574  * tracking context related to the buffers.
2575  */
2576 struct vb2_fileio_buf {
2577         void *vaddr;
2578         unsigned int size;
2579         unsigned int pos;
2580         unsigned int queued:1;
2581 };
2582
2583 /*
2584  * struct vb2_fileio_data - queue context used by file io emulator
2585  *
2586  * @cur_index:  the index of the buffer currently being read from or
2587  *              written to. If equal to q->num_buffers then a new buffer
2588  *              must be dequeued.
2589  * @initial_index: in the read() case all buffers are queued up immediately
2590  *              in __vb2_init_fileio() and __vb2_perform_fileio() just cycles
2591  *              buffers. However, in the write() case no buffers are initially
2592  *              queued, instead whenever a buffer is full it is queued up by
2593  *              __vb2_perform_fileio(). Only once all available buffers have
2594  *              been queued up will __vb2_perform_fileio() start to dequeue
2595  *              buffers. This means that initially __vb2_perform_fileio()
2596  *              needs to know what buffer index to use when it is queuing up
2597  *              the buffers for the first time. That initial index is stored
2598  *              in this field. Once it is equal to q->num_buffers all
2599  *              available buffers have been queued and __vb2_perform_fileio()
2600  *              should start the normal dequeue/queue cycle.
2601  *
2602  * vb2 provides a compatibility layer and emulator of file io (read and
2603  * write) calls on top of streaming API. For proper operation it required
2604  * this structure to save the driver state between each call of the read
2605  * or write function.
2606  */
2607 struct vb2_fileio_data {
2608         unsigned int count;
2609         unsigned int type;
2610         unsigned int memory;
2611         struct vb2_fileio_buf bufs[VB2_MAX_FRAME];
2612         unsigned int cur_index;
2613         unsigned int initial_index;
2614         unsigned int q_count;
2615         unsigned int dq_count;
2616         unsigned read_once:1;
2617         unsigned write_immediately:1;
2618 };
2619
2620 /*
2621  * __vb2_init_fileio() - initialize file io emulator
2622  * @q:          videobuf2 queue
2623  * @read:       mode selector (1 means read, 0 means write)
2624  */
2625 static int __vb2_init_fileio(struct vb2_queue *q, int read)
2626 {
2627         struct vb2_fileio_data *fileio;
2628         int i, ret;
2629         unsigned int count = 0;
2630
2631         /*
2632          * Sanity check
2633          */
2634         if (WARN_ON((read && !(q->io_modes & VB2_READ)) ||
2635                     (!read && !(q->io_modes & VB2_WRITE))))
2636                 return -EINVAL;
2637
2638         /*
2639          * Check if device supports mapping buffers to kernel virtual space.
2640          */
2641         if (!q->mem_ops->vaddr)
2642                 return -EBUSY;
2643
2644         /*
2645          * Check if streaming api has not been already activated.
2646          */
2647         if (q->streaming || q->num_buffers > 0)
2648                 return -EBUSY;
2649
2650         /*
2651          * Start with count 1, driver can increase it in queue_setup()
2652          */
2653         count = 1;
2654
2655         dprintk(q, 3, "setting up file io: mode %s, count %d, read_once %d, write_immediately %d\n",
2656                 (read) ? "read" : "write", count, q->fileio_read_once,
2657                 q->fileio_write_immediately);
2658
2659         fileio = kzalloc(sizeof(*fileio), GFP_KERNEL);
2660         if (fileio == NULL)
2661                 return -ENOMEM;
2662
2663         fileio->read_once = q->fileio_read_once;
2664         fileio->write_immediately = q->fileio_write_immediately;
2665
2666         /*
2667          * Request buffers and use MMAP type to force driver
2668          * to allocate buffers by itself.
2669          */
2670         fileio->count = count;
2671         fileio->memory = VB2_MEMORY_MMAP;
2672         fileio->type = q->type;
2673         q->fileio = fileio;
2674         ret = vb2_core_reqbufs(q, fileio->memory, 0, &fileio->count);
2675         if (ret)
2676                 goto err_kfree;
2677
2678         /*
2679          * Check if plane_count is correct
2680          * (multiplane buffers are not supported).
2681          */
2682         if (q->bufs[0]->num_planes != 1) {
2683                 ret = -EBUSY;
2684                 goto err_reqbufs;
2685         }
2686
2687         /*
2688          * Get kernel address of each buffer.
2689          */
2690         for (i = 0; i < q->num_buffers; i++) {
2691                 fileio->bufs[i].vaddr = vb2_plane_vaddr(q->bufs[i], 0);
2692                 if (fileio->bufs[i].vaddr == NULL) {
2693                         ret = -EINVAL;
2694                         goto err_reqbufs;
2695                 }
2696                 fileio->bufs[i].size = vb2_plane_size(q->bufs[i], 0);
2697         }
2698
2699         /*
2700          * Read mode requires pre queuing of all buffers.
2701          */
2702         if (read) {
2703                 /*
2704                  * Queue all buffers.
2705                  */
2706                 for (i = 0; i < q->num_buffers; i++) {
2707                         ret = vb2_core_qbuf(q, i, NULL, NULL);
2708                         if (ret)
2709                                 goto err_reqbufs;
2710                         fileio->bufs[i].queued = 1;
2711                 }
2712                 /*
2713                  * All buffers have been queued, so mark that by setting
2714                  * initial_index to q->num_buffers
2715                  */
2716                 fileio->initial_index = q->num_buffers;
2717                 fileio->cur_index = q->num_buffers;
2718         }
2719
2720         /*
2721          * Start streaming.
2722          */
2723         ret = vb2_core_streamon(q, q->type);
2724         if (ret)
2725                 goto err_reqbufs;
2726
2727         return ret;
2728
2729 err_reqbufs:
2730         fileio->count = 0;
2731         vb2_core_reqbufs(q, fileio->memory, 0, &fileio->count);
2732
2733 err_kfree:
2734         q->fileio = NULL;
2735         kfree(fileio);
2736         return ret;
2737 }
2738
2739 /*
2740  * __vb2_cleanup_fileio() - free resourced used by file io emulator
2741  * @q:          videobuf2 queue
2742  */
2743 static int __vb2_cleanup_fileio(struct vb2_queue *q)
2744 {
2745         struct vb2_fileio_data *fileio = q->fileio;
2746
2747         if (fileio) {
2748                 vb2_core_streamoff(q, q->type);
2749                 q->fileio = NULL;
2750                 fileio->count = 0;
2751                 vb2_core_reqbufs(q, fileio->memory, 0, &fileio->count);
2752                 kfree(fileio);
2753                 dprintk(q, 3, "file io emulator closed\n");
2754         }
2755         return 0;
2756 }
2757
2758 /*
2759  * __vb2_perform_fileio() - perform a single file io (read or write) operation
2760  * @q:          videobuf2 queue
2761  * @data:       pointed to target userspace buffer
2762  * @count:      number of bytes to read or write
2763  * @ppos:       file handle position tracking pointer
2764  * @nonblock:   mode selector (1 means blocking calls, 0 means nonblocking)
2765  * @read:       access mode selector (1 means read, 0 means write)
2766  */
2767 static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_t count,
2768                 loff_t *ppos, int nonblock, int read)
2769 {
2770         struct vb2_fileio_data *fileio;
2771         struct vb2_fileio_buf *buf;
2772         bool is_multiplanar = q->is_multiplanar;
2773         /*
2774          * When using write() to write data to an output video node the vb2 core
2775          * should copy timestamps if V4L2_BUF_FLAG_TIMESTAMP_COPY is set. Nobody
2776          * else is able to provide this information with the write() operation.
2777          */
2778         bool copy_timestamp = !read && q->copy_timestamp;
2779         unsigned index;
2780         int ret;
2781
2782         dprintk(q, 3, "mode %s, offset %ld, count %zd, %sblocking\n",
2783                 read ? "read" : "write", (long)*ppos, count,
2784                 nonblock ? "non" : "");
2785
2786         if (!data)
2787                 return -EINVAL;
2788
2789         if (q->waiting_in_dqbuf) {
2790                 dprintk(q, 3, "another dup()ped fd is %s\n",
2791                         read ? "reading" : "writing");
2792                 return -EBUSY;
2793         }
2794
2795         /*
2796          * Initialize emulator on first call.
2797          */
2798         if (!vb2_fileio_is_active(q)) {
2799                 ret = __vb2_init_fileio(q, read);
2800                 dprintk(q, 3, "vb2_init_fileio result: %d\n", ret);
2801                 if (ret)
2802                         return ret;
2803         }
2804         fileio = q->fileio;
2805
2806         /*
2807          * Check if we need to dequeue the buffer.
2808          */
2809         index = fileio->cur_index;
2810         if (index >= q->num_buffers) {
2811                 struct vb2_buffer *b;
2812
2813                 /*
2814                  * Call vb2_dqbuf to get buffer back.
2815                  */
2816                 ret = vb2_core_dqbuf(q, &index, NULL, nonblock);
2817                 dprintk(q, 5, "vb2_dqbuf result: %d\n", ret);
2818                 if (ret)
2819                         return ret;
2820                 fileio->dq_count += 1;
2821
2822                 fileio->cur_index = index;
2823                 buf = &fileio->bufs[index];
2824                 b = q->bufs[index];
2825
2826                 /*
2827                  * Get number of bytes filled by the driver
2828                  */
2829                 buf->pos = 0;
2830                 buf->queued = 0;
2831                 buf->size = read ? vb2_get_plane_payload(q->bufs[index], 0)
2832                                  : vb2_plane_size(q->bufs[index], 0);
2833                 /* Compensate for data_offset on read in the multiplanar case. */
2834                 if (is_multiplanar && read &&
2835                                 b->planes[0].data_offset < buf->size) {
2836                         buf->pos = b->planes[0].data_offset;
2837                         buf->size -= buf->pos;
2838                 }
2839         } else {
2840                 buf = &fileio->bufs[index];
2841         }
2842
2843         /*
2844          * Limit count on last few bytes of the buffer.
2845          */
2846         if (buf->pos + count > buf->size) {
2847                 count = buf->size - buf->pos;
2848                 dprintk(q, 5, "reducing read count: %zd\n", count);
2849         }
2850
2851         /*
2852          * Transfer data to userspace.
2853          */
2854         dprintk(q, 3, "copying %zd bytes - buffer %d, offset %u\n",
2855                 count, index, buf->pos);
2856         if (read)
2857                 ret = copy_to_user(data, buf->vaddr + buf->pos, count);
2858         else
2859                 ret = copy_from_user(buf->vaddr + buf->pos, data, count);
2860         if (ret) {
2861                 dprintk(q, 3, "error copying data\n");
2862                 return -EFAULT;
2863         }
2864
2865         /*
2866          * Update counters.
2867          */
2868         buf->pos += count;
2869         *ppos += count;
2870
2871         /*
2872          * Queue next buffer if required.
2873          */
2874         if (buf->pos == buf->size || (!read && fileio->write_immediately)) {
2875                 struct vb2_buffer *b = q->bufs[index];
2876
2877                 /*
2878                  * Check if this is the last buffer to read.
2879                  */
2880                 if (read && fileio->read_once && fileio->dq_count == 1) {
2881                         dprintk(q, 3, "read limit reached\n");
2882                         return __vb2_cleanup_fileio(q);
2883                 }
2884
2885                 /*
2886                  * Call vb2_qbuf and give buffer to the driver.
2887                  */
2888                 b->planes[0].bytesused = buf->pos;
2889
2890                 if (copy_timestamp)
2891                         b->timestamp = ktime_get_ns();
2892                 ret = vb2_core_qbuf(q, index, NULL, NULL);
2893                 dprintk(q, 5, "vb2_dbuf result: %d\n", ret);
2894                 if (ret)
2895                         return ret;
2896
2897                 /*
2898                  * Buffer has been queued, update the status
2899                  */
2900                 buf->pos = 0;
2901                 buf->queued = 1;
2902                 buf->size = vb2_plane_size(q->bufs[index], 0);
2903                 fileio->q_count += 1;
2904                 /*
2905                  * If we are queuing up buffers for the first time, then
2906                  * increase initial_index by one.
2907                  */
2908                 if (fileio->initial_index < q->num_buffers)
2909                         fileio->initial_index++;
2910                 /*
2911                  * The next buffer to use is either a buffer that's going to be
2912                  * queued for the first time (initial_index < q->num_buffers)
2913                  * or it is equal to q->num_buffers, meaning that the next
2914                  * time we need to dequeue a buffer since we've now queued up
2915                  * all the 'first time' buffers.
2916                  */
2917                 fileio->cur_index = fileio->initial_index;
2918         }
2919
2920         /*
2921          * Return proper number of bytes processed.
2922          */
2923         if (ret == 0)
2924                 ret = count;
2925         return ret;
2926 }
2927
2928 size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count,
2929                 loff_t *ppos, int nonblocking)
2930 {
2931         return __vb2_perform_fileio(q, data, count, ppos, nonblocking, 1);
2932 }
2933 EXPORT_SYMBOL_GPL(vb2_read);
2934
2935 size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count,
2936                 loff_t *ppos, int nonblocking)
2937 {
2938         return __vb2_perform_fileio(q, (char __user *) data, count,
2939                                                         ppos, nonblocking, 0);
2940 }
2941 EXPORT_SYMBOL_GPL(vb2_write);
2942
2943 struct vb2_threadio_data {
2944         struct task_struct *thread;
2945         vb2_thread_fnc fnc;
2946         void *priv;
2947         bool stop;
2948 };
2949
2950 static int vb2_thread(void *data)
2951 {
2952         struct vb2_queue *q = data;
2953         struct vb2_threadio_data *threadio = q->threadio;
2954         bool copy_timestamp = false;
2955         unsigned prequeue = 0;
2956         unsigned index = 0;
2957         int ret = 0;
2958
2959         if (q->is_output) {
2960                 prequeue = q->num_buffers;
2961                 copy_timestamp = q->copy_timestamp;
2962         }
2963
2964         set_freezable();
2965
2966         for (;;) {
2967                 struct vb2_buffer *vb;
2968
2969                 /*
2970                  * Call vb2_dqbuf to get buffer back.
2971                  */
2972                 if (prequeue) {
2973                         vb = q->bufs[index++];
2974                         prequeue--;
2975                 } else {
2976                         call_void_qop(q, wait_finish, q);
2977                         if (!threadio->stop)
2978                                 ret = vb2_core_dqbuf(q, &index, NULL, 0);
2979                         call_void_qop(q, wait_prepare, q);
2980                         dprintk(q, 5, "file io: vb2_dqbuf result: %d\n", ret);
2981                         if (!ret)
2982                                 vb = q->bufs[index];
2983                 }
2984                 if (ret || threadio->stop)
2985                         break;
2986                 try_to_freeze();
2987
2988                 if (vb->state != VB2_BUF_STATE_ERROR)
2989                         if (threadio->fnc(vb, threadio->priv))
2990                                 break;
2991                 call_void_qop(q, wait_finish, q);
2992                 if (copy_timestamp)
2993                         vb->timestamp = ktime_get_ns();
2994                 if (!threadio->stop)
2995                         ret = vb2_core_qbuf(q, vb->index, NULL, NULL);
2996                 call_void_qop(q, wait_prepare, q);
2997                 if (ret || threadio->stop)
2998                         break;
2999         }
3000
3001         /* Hmm, linux becomes *very* unhappy without this ... */
3002         while (!kthread_should_stop()) {
3003                 set_current_state(TASK_INTERRUPTIBLE);
3004                 schedule();
3005         }
3006         return 0;
3007 }
3008
3009 /*
3010  * This function should not be used for anything else but the videobuf2-dvb
3011  * support. If you think you have another good use-case for this, then please
3012  * contact the linux-media mailinglist first.
3013  */
3014 int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv,
3015                      const char *thread_name)
3016 {
3017         struct vb2_threadio_data *threadio;
3018         int ret = 0;
3019
3020         if (q->threadio)
3021                 return -EBUSY;
3022         if (vb2_is_busy(q))
3023                 return -EBUSY;
3024         if (WARN_ON(q->fileio))
3025                 return -EBUSY;
3026
3027         threadio = kzalloc(sizeof(*threadio), GFP_KERNEL);
3028         if (threadio == NULL)
3029                 return -ENOMEM;
3030         threadio->fnc = fnc;
3031         threadio->priv = priv;
3032
3033         ret = __vb2_init_fileio(q, !q->is_output);
3034         dprintk(q, 3, "file io: vb2_init_fileio result: %d\n", ret);
3035         if (ret)
3036                 goto nomem;
3037         q->threadio = threadio;
3038         threadio->thread = kthread_run(vb2_thread, q, "vb2-%s", thread_name);
3039         if (IS_ERR(threadio->thread)) {
3040                 ret = PTR_ERR(threadio->thread);
3041                 threadio->thread = NULL;
3042                 goto nothread;
3043         }
3044         return 0;
3045
3046 nothread:
3047         __vb2_cleanup_fileio(q);
3048 nomem:
3049         kfree(threadio);
3050         return ret;
3051 }
3052 EXPORT_SYMBOL_GPL(vb2_thread_start);
3053
3054 int vb2_thread_stop(struct vb2_queue *q)
3055 {
3056         struct vb2_threadio_data *threadio = q->threadio;
3057         int err;
3058
3059         if (threadio == NULL)
3060                 return 0;
3061         threadio->stop = true;
3062         /* Wake up all pending sleeps in the thread */
3063         vb2_queue_error(q);
3064         err = kthread_stop(threadio->thread);
3065         __vb2_cleanup_fileio(q);
3066         threadio->thread = NULL;
3067         kfree(threadio);
3068         q->threadio = NULL;
3069         return err;
3070 }
3071 EXPORT_SYMBOL_GPL(vb2_thread_stop);
3072
3073 MODULE_DESCRIPTION("Media buffer core framework");
3074 MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski");
3075 MODULE_LICENSE("GPL");
3076 MODULE_IMPORT_NS(DMA_BUF);