drivers/media/video/video-buf.c

   1 /*
   2  *
   3  * generic helper functions for video4linux capture buffers, to handle
   4  * memory management and PCI DMA.
   5  * Right now, bttv, saa7134, saa7146 and cx88 use it.
   6  *
   7  * The functions expect the hardware being able to scatter gatter
   8  * (i.e. the buffers are not linear in physical memory, but fragmented
   9  * into PAGE_SIZE chunks).  They also assume the driver does not need
  10  * to touch the video data.
  11  *
  12  * device specific map/unmap/sync stuff now are mapped as operations
  13  * to allow its usage by USB and virtual devices.
  14  *
  15  * (c) 2001-2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs]
  16  * (c) 2006 Mauro Carvalho Chehab <mchehab@infradead.org>
  17  * (c) 2006 Ted Walther and John Sokol
  18  *
  19  * This program is free software; you can redistribute it and/or modify
  20  * it under the terms of the GNU General Public License as published by
  21  * the Free Software Foundation; either version 2 of the License, or
  22  * (at your option) any later version.
  23  */
  24
  25 #include <linux/init.h>
  26 #include <linux/module.h>
  27 #include <linux/moduleparam.h>
  28 #include <linux/vmalloc.h>
  29 #include <linux/pagemap.h>
  30 #include <linux/slab.h>
  31 #include <linux/pci.h>
  32 #include <linux/interrupt.h>
  33 #include <asm/page.h>
  34 #include <asm/pgtable.h>
  35
  36 #include <media/video-buf.h>
  37
  38 #define MAGIC_DMABUF 0x19721112
  39 #define MAGIC_BUFFER 0x20040302
  40 #define MAGIC_CHECK(is,should)  if (unlikely((is) != (should))) \
  41         { printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); }
  42
  43 static int debug = 0;
  44 module_param(debug, int, 0644);
  45
  46 MODULE_DESCRIPTION("helper module to manage video4linux pci dma buffers");
  47 MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
  48 MODULE_LICENSE("GPL");
  49
  50 #define dprintk(level, fmt, arg...)     if (debug >= level) \
  51         printk(KERN_DEBUG "vbuf: " fmt , ## arg)
  52
  53 struct scatterlist*
  54 videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages)
  55 {
  56         struct scatterlist *sglist;
  57         struct page *pg;
  58         int i;
  59
  60         sglist = kcalloc(nr_pages, sizeof(struct scatterlist), GFP_KERNEL);
  61         if (NULL == sglist)
  62                 return NULL;
  63         for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
  64                 pg = vmalloc_to_page(virt);
  65                 if (NULL == pg)
  66                         goto err;
  67                 BUG_ON(PageHighMem(pg));
  68                 sglist[i].page   = pg;
  69                 sglist[i].length = PAGE_SIZE;
  70         }
  71         return sglist;
  72
  73  err:
  74         kfree(sglist);
  75         return NULL;
  76 }
  77
  78 struct scatterlist*
  79 videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset)
  80 {
  81         struct scatterlist *sglist;
  82         int i = 0;
  83
  84         if (NULL == pages[0])
  85                 return NULL;
  86         sglist = kcalloc(nr_pages, sizeof(*sglist), GFP_KERNEL);
  87         if (NULL == sglist)
  88                 return NULL;
  89
  90         if (NULL == pages[0])
  91                 goto nopage;
  92         if (PageHighMem(pages[0]))
  93                 /* DMA to highmem pages might not work */
  94                 goto highmem;
  95         sglist[0].page   = pages[0];
  96         sglist[0].offset = offset;
  97         sglist[0].length = PAGE_SIZE - offset;
  98         for (i = 1; i < nr_pages; i++) {
  99                 if (NULL == pages[i])
 100                         goto nopage;
 101                 if (PageHighMem(pages[i]))
 102                         goto highmem;
 103                 sglist[i].page   = pages[i];
 104                 sglist[i].length = PAGE_SIZE;
 105         }
 106         return sglist;
 107
 108  nopage:
 109         dprintk(2,"sgl: oops - no page\n");
 110         kfree(sglist);
 111         return NULL;
 112
 113  highmem:
 114         dprintk(2,"sgl: oops - highmem page\n");
 115         kfree(sglist);
 116         return NULL;
 117 }
 118
 119 /* --------------------------------------------------------------------- */
 120
 121 void videobuf_dma_init(struct videobuf_dmabuf *dma)
 122 {
 123         memset(dma,0,sizeof(*dma));
 124         dma->magic = MAGIC_DMABUF;
 125 }
 126
 127 int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
 128                            unsigned long data, unsigned long size)
 129 {
 130         unsigned long first,last;
 131         int err, rw = 0;
 132
 133         dma->direction = direction;
 134         switch (dma->direction) {
 135         case PCI_DMA_FROMDEVICE: rw = READ;  break;
 136         case PCI_DMA_TODEVICE:   rw = WRITE; break;
 137         default:                 BUG();
 138         }
 139
 140         first = (data          & PAGE_MASK) >> PAGE_SHIFT;
 141         last  = ((data+size-1) & PAGE_MASK) >> PAGE_SHIFT;
 142         dma->offset   = data & ~PAGE_MASK;
 143         dma->nr_pages = last-first+1;
 144         dma->pages = kmalloc(dma->nr_pages * sizeof(struct page*),
 145                              GFP_KERNEL);
 146         if (NULL == dma->pages)
 147                 return -ENOMEM;
 148         dprintk(1,"init user [0x%lx+0x%lx => %d pages]\n",
 149                 data,size,dma->nr_pages);
 150
 151         down_read(&current->mm->mmap_sem);
 152         err = get_user_pages(current,current->mm,
 153                              data & PAGE_MASK, dma->nr_pages,
 154                              rw == READ, 1, /* force */
 155                              dma->pages, NULL);
 156         up_read(&current->mm->mmap_sem);
 157         if (err != dma->nr_pages) {
 158                 dma->nr_pages = (err >= 0) ? err : 0;
 159                 dprintk(1,"get_user_pages: err=%d [%d]\n",err,dma->nr_pages);
 160                 return err < 0 ? err : -EINVAL;
 161         }
 162         return 0;
 163 }
 164
 165 int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
 166                              int nr_pages)
 167 {
 168         dprintk(1,"init kernel [%d pages]\n",nr_pages);
 169         dma->direction = direction;
 170         dma->vmalloc = vmalloc_32(nr_pages << PAGE_SHIFT);
 171         if (NULL == dma->vmalloc) {
 172                 dprintk(1,"vmalloc_32(%d pages) failed\n",nr_pages);
 173                 return -ENOMEM;
 174         }
 175         dprintk(1,"vmalloc is at addr 0x%08lx, size=%d\n",
 176                                 (unsigned long)dma->vmalloc,
 177                                 nr_pages << PAGE_SHIFT);
 178         memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT);
 179         dma->nr_pages = nr_pages;
 180         return 0;
 181 }
 182
 183 int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
 184                               dma_addr_t addr, int nr_pages)
 185 {
 186         dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n",
 187                 nr_pages,(unsigned long)addr);
 188         dma->direction = direction;
 189         if (0 == addr)
 190                 return -EINVAL;
 191
 192         dma->bus_addr = addr;
 193         dma->nr_pages = nr_pages;
 194         return 0;
 195 }
 196
 197 int videobuf_dma_map(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
 198 {
 199         void                   *dev=q->dev;
 200
 201         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 202         BUG_ON(0 == dma->nr_pages);
 203
 204         if (dma->pages) {
 205                 dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
 206                                                    dma->offset);
 207         }
 208         if (dma->vmalloc) {
 209                 dma->sglist = videobuf_vmalloc_to_sg
 210                                                 (dma->vmalloc,dma->nr_pages);
 211         }
 212         if (dma->bus_addr) {
 213                 dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
 214                 if (NULL != dma->sglist) {
 215                         dma->sglen  = 1;
 216                         sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK;
 217                         dma->sglist[0].offset           = dma->bus_addr & ~PAGE_MASK;
 218                         sg_dma_len(&dma->sglist[0])     = dma->nr_pages * PAGE_SIZE;
 219                 }
 220         }
 221         if (NULL == dma->sglist) {
 222                 dprintk(1,"scatterlist is NULL\n");
 223                 return -ENOMEM;
 224         }
 225         if (!dma->bus_addr) {
 226                 if (q->ops->vb_map_sg) {
 227                         dma->sglen = q->ops->vb_map_sg(dev,dma->sglist,
 228                                         dma->nr_pages, dma->direction);
 229                 }
 230                 if (0 == dma->sglen) {
 231                         printk(KERN_WARNING
 232                                "%s: videobuf_map_sg failed\n",__FUNCTION__);
 233                         kfree(dma->sglist);
 234                         dma->sglist = NULL;
 235                         dma->sglen = 0;
 236                         return -EIO;
 237                 }
 238         }
 239         return 0;
 240 }
 241
 242 int videobuf_dma_sync(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
 243 {
 244         void                   *dev=q->dev;
 245
 246         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 247         BUG_ON(!dma->sglen);
 248
 249         if (!dma->bus_addr && q->ops->vb_dma_sync_sg)
 250                 q->ops->vb_dma_sync_sg(dev,dma->sglist,dma->nr_pages,
 251                                                         dma->direction);
 252
 253         return 0;
 254 }
 255
 256 int videobuf_dma_unmap(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
 257 {
 258         void                   *dev=q->dev;
 259
 260         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 261         if (!dma->sglen)
 262                 return 0;
 263
 264         if (!dma->bus_addr && q->ops->vb_unmap_sg)
 265                         q->ops->vb_unmap_sg(dev,dma->sglist,dma->nr_pages,
 266                                                         dma->direction);
 267         kfree(dma->sglist);
 268         dma->sglist = NULL;
 269         dma->sglen = 0;
 270         return 0;
 271 }
 272
 273 int videobuf_dma_free(struct videobuf_dmabuf *dma)
 274 {
 275         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 276         BUG_ON(dma->sglen);
 277
 278         if (dma->pages) {
 279                 int i;
 280                 for (i=0; i < dma->nr_pages; i++)
 281                         page_cache_release(dma->pages[i]);
 282                 kfree(dma->pages);
 283                 dma->pages = NULL;
 284         }
 285
 286         vfree(dma->vmalloc);
 287         dma->vmalloc = NULL;
 288
 289         if (dma->bus_addr) {
 290                 dma->bus_addr = 0;
 291         }
 292         dma->direction = PCI_DMA_NONE;
 293         return 0;
 294 }
 295
 296 /* --------------------------------------------------------------------- */
 297
 298 void* videobuf_alloc(unsigned int size)
 299 {
 300         struct videobuf_buffer *vb;
 301
 302         vb = kzalloc(size,GFP_KERNEL);
 303         if (NULL != vb) {
 304                 videobuf_dma_init(&vb->dma);
 305                 init_waitqueue_head(&vb->done);
 306                 vb->magic     = MAGIC_BUFFER;
 307         }
 308         return vb;
 309 }
 310
 311 int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
 312 {
 313         int retval = 0;
 314         DECLARE_WAITQUEUE(wait, current);
 315
 316         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 317         add_wait_queue(&vb->done, &wait);
 318         while (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED) {
 319                 if (non_blocking) {
 320                         retval = -EAGAIN;
 321                         break;
 322                 }
 323                 set_current_state(intr  ? TASK_INTERRUPTIBLE
 324                                         : TASK_UNINTERRUPTIBLE);
 325                 if (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED)
 326                         schedule();
 327                 set_current_state(TASK_RUNNING);
 328                 if (intr && signal_pending(current)) {
 329                         dprintk(1,"buffer waiton: -EINTR\n");
 330                         retval = -EINTR;
 331                         break;
 332                 }
 333         }
 334         remove_wait_queue(&vb->done, &wait);
 335         return retval;
 336 }
 337
 338 int
 339 videobuf_iolock(struct videobuf_queue* q, struct videobuf_buffer *vb,
 340                 struct v4l2_framebuffer *fbuf)
 341 {
 342         int err,pages;
 343         dma_addr_t bus;
 344
 345         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 346         switch (vb->memory) {
 347         case V4L2_MEMORY_MMAP:
 348         case V4L2_MEMORY_USERPTR:
 349                 if (0 == vb->baddr) {
 350                         /* no userspace addr -- kernel bounce buffer */
 351                         pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
 352                         err = videobuf_dma_init_kernel(&vb->dma,PCI_DMA_FROMDEVICE,
 353                                                        pages);
 354                         if (0 != err)
 355                                 return err;
 356                 } else {
 357                         /* dma directly to userspace */
 358                         err = videobuf_dma_init_user(&vb->dma,PCI_DMA_FROMDEVICE,
 359                                                      vb->baddr,vb->bsize);
 360                         if (0 != err)
 361                                 return err;
 362                 }
 363                 break;
 364         case V4L2_MEMORY_OVERLAY:
 365                 if (NULL == fbuf)
 366                         return -EINVAL;
 367                 /* FIXME: need sanity checks for vb->boff */
 368                 bus   = (dma_addr_t)fbuf->base + vb->boff;
 369                 pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
 370                 err = videobuf_dma_init_overlay(&vb->dma,PCI_DMA_FROMDEVICE,
 371                                                 bus, pages);
 372                 if (0 != err)
 373                         return err;
 374                 break;
 375         default:
 376                 BUG();
 377         }
 378         err = videobuf_dma_map(q,&vb->dma);
 379         if (0 != err)
 380                 return err;
 381
 382         return 0;
 383 }
 384
 385 /* --------------------------------------------------------------------- */
 386
 387 void videobuf_queue_pci(struct videobuf_queue* q)
 388 {
 389         /* If not specified, defaults to PCI map sg */
 390         if (!q->ops->vb_map_sg)
 391                 q->ops->vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 392
 393         if (!q->ops->vb_dma_sync_sg)
 394                 q->ops->vb_dma_sync_sg=(vb_map_sg_t *)pci_dma_sync_sg_for_cpu;
 395         if (!q->ops->vb_unmap_sg)
 396                 q->ops->vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 397 }
 398
 399 int videobuf_pci_dma_map(struct pci_dev *pci,struct videobuf_dmabuf *dma)
 400 {
 401         struct videobuf_queue q;
 402         struct videobuf_queue_ops qops;
 403
 404         q.dev=pci;
 405         qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 406         qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 407         q.ops = &qops;
 408
 409         return (videobuf_dma_map(&q,dma));
 410 }
 411
 412 int videobuf_pci_dma_unmap(struct pci_dev *pci,struct videobuf_dmabuf *dma)
 413 {
 414         struct videobuf_queue q;
 415         struct videobuf_queue_ops qops;
 416
 417         q.dev=pci;
 418         qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 419         qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 420         q.ops = &qops;
 421
 422         return (videobuf_dma_unmap(&q,dma));
 423 }
 424
 425 void videobuf_queue_init(struct videobuf_queue* q,
 426                          struct videobuf_queue_ops *ops,
 427                          void *dev,
 428                          spinlock_t *irqlock,
 429                          enum v4l2_buf_type type,
 430                          enum v4l2_field field,
 431                          unsigned int msize,
 432                          void *priv)
 433 {
 434         memset(q,0,sizeof(*q));
 435         q->irqlock = irqlock;
 436         q->dev     = dev;
 437         q->type    = type;
 438         q->field   = field;
 439         q->msize   = msize;
 440         q->ops     = ops;
 441         q->priv_data = priv;
 442
 443         videobuf_queue_pci(q);
 444
 445         mutex_init(&q->lock);
 446         INIT_LIST_HEAD(&q->stream);
 447 }
 448
 449 int
 450 videobuf_queue_is_busy(struct videobuf_queue *q)
 451 {
 452         int i;
 453
 454         if (q->streaming) {
 455                 dprintk(1,"busy: streaming active\n");
 456                 return 1;
 457         }
 458         if (q->reading) {
 459                 dprintk(1,"busy: pending read #1\n");
 460                 return 1;
 461         }
 462         if (q->read_buf) {
 463                 dprintk(1,"busy: pending read #2\n");
 464                 return 1;
 465         }
 466         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 467                 if (NULL == q->bufs[i])
 468                         continue;
 469                 if (q->bufs[i]->map) {
 470                         dprintk(1,"busy: buffer #%d mapped\n",i);
 471                         return 1;
 472                 }
 473                 if (q->bufs[i]->state == STATE_QUEUED) {
 474                         dprintk(1,"busy: buffer #%d queued\n",i);
 475                         return 1;
 476                 }
 477                 if (q->bufs[i]->state == STATE_ACTIVE) {
 478                         dprintk(1,"busy: buffer #%d avtive\n",i);
 479                         return 1;
 480                 }
 481         }
 482         return 0;
 483 }
 484
 485 void
 486 videobuf_queue_cancel(struct videobuf_queue *q)
 487 {
 488         unsigned long flags=0;
 489         int i;
 490
 491         /* remove queued buffers from list */
 492         if (q->irqlock)
 493                 spin_lock_irqsave(q->irqlock,flags);
 494         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 495                 if (NULL == q->bufs[i])
 496                         continue;
 497                 if (q->bufs[i]->state == STATE_QUEUED) {
 498                         list_del(&q->bufs[i]->queue);
 499                         q->bufs[i]->state = STATE_ERROR;
 500                 }
 501         }
 502         if (q->irqlock)
 503                 spin_unlock_irqrestore(q->irqlock,flags);
 504
 505         /* free all buffers + clear queue */
 506         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 507                 if (NULL == q->bufs[i])
 508                         continue;
 509                 q->ops->buf_release(q,q->bufs[i]);
 510         }
 511         INIT_LIST_HEAD(&q->stream);
 512 }
 513
 514 /* --------------------------------------------------------------------- */
 515
 516 enum v4l2_field
 517 videobuf_next_field(struct videobuf_queue *q)
 518 {
 519         enum v4l2_field field = q->field;
 520
 521         BUG_ON(V4L2_FIELD_ANY == field);
 522
 523         if (V4L2_FIELD_ALTERNATE == field) {
 524                 if (V4L2_FIELD_TOP == q->last) {
 525                         field   = V4L2_FIELD_BOTTOM;
 526                         q->last = V4L2_FIELD_BOTTOM;
 527                 } else {
 528                         field   = V4L2_FIELD_TOP;
 529                         q->last = V4L2_FIELD_TOP;
 530                 }
 531         }
 532         return field;
 533 }
 534
 535 void
 536 videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb,
 537                 enum v4l2_buf_type type)
 538 {
 539         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 540
 541         b->index    = vb->i;
 542         b->type     = type;
 543
 544         b->memory   = vb->memory;
 545         switch (b->memory) {
 546         case V4L2_MEMORY_MMAP:
 547                 b->m.offset  = vb->boff;
 548                 b->length    = vb->bsize;
 549                 break;
 550         case V4L2_MEMORY_USERPTR:
 551                 b->m.userptr = vb->baddr;
 552                 b->length    = vb->bsize;
 553                 break;
 554         case V4L2_MEMORY_OVERLAY:
 555                 b->m.offset  = vb->boff;
 556                 break;
 557         }
 558
 559         b->flags    = 0;
 560         if (vb->map)
 561                 b->flags |= V4L2_BUF_FLAG_MAPPED;
 562
 563         switch (vb->state) {
 564         case STATE_PREPARED:
 565         case STATE_QUEUED:
 566         case STATE_ACTIVE:
 567                 b->flags |= V4L2_BUF_FLAG_QUEUED;
 568                 break;
 569         case STATE_DONE:
 570         case STATE_ERROR:
 571                 b->flags |= V4L2_BUF_FLAG_DONE;
 572                 break;
 573         case STATE_NEEDS_INIT:
 574         case STATE_IDLE:
 575                 /* nothing */
 576                 break;
 577         }
 578
 579         if (vb->input != UNSET) {
 580                 b->flags |= V4L2_BUF_FLAG_INPUT;
 581                 b->input  = vb->input;
 582         }
 583
 584         b->field     = vb->field;
 585         b->timestamp = vb->ts;
 586         b->bytesused = vb->size;
 587         b->sequence  = vb->field_count >> 1;
 588 }
 589
 590 int
 591 videobuf_reqbufs(struct videobuf_queue *q,
 592                  struct v4l2_requestbuffers *req)
 593 {
 594         unsigned int size,count;
 595         int retval;
 596
 597         if (req->type != q->type) {
 598                 dprintk(1,"reqbufs: queue type invalid\n");
 599                 return -EINVAL;
 600         }
 601         if (req->count < 1) {
 602                 dprintk(1,"reqbufs: count invalid (%d)\n",req->count);
 603                 return -EINVAL;
 604         }
 605         if (req->memory != V4L2_MEMORY_MMAP     &&
 606             req->memory != V4L2_MEMORY_USERPTR  &&
 607             req->memory != V4L2_MEMORY_OVERLAY) {
 608                 dprintk(1,"reqbufs: memory type invalid\n");
 609                 return -EINVAL;
 610         }
 611
 612         if (q->streaming) {
 613                 dprintk(1,"reqbufs: streaming already exists\n");
 614                 return -EBUSY;
 615         }
 616         if (!list_empty(&q->stream)) {
 617                 dprintk(1,"reqbufs: stream running\n");
 618                 return -EBUSY;
 619         }
 620
 621         mutex_lock(&q->lock);
 622         count = req->count;
 623         if (count > VIDEO_MAX_FRAME)
 624                 count = VIDEO_MAX_FRAME;
 625         size = 0;
 626         q->ops->buf_setup(q,&count,&size);
 627         size = PAGE_ALIGN(size);
 628         dprintk(1,"reqbufs: bufs=%d, size=0x%x [%d pages total]\n",
 629                 count, size, (count*size)>>PAGE_SHIFT);
 630
 631         retval = videobuf_mmap_setup(q,count,size,req->memory);
 632         if (retval < 0) {
 633                 dprintk(1,"reqbufs: mmap setup returned %d\n",retval);
 634                 goto done;
 635         }
 636
 637         req->count = count;
 638
 639  done:
 640         mutex_unlock(&q->lock);
 641         return retval;
 642 }
 643
 644 int
 645 videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b)
 646 {
 647         if (unlikely(b->type != q->type)) {
 648                 dprintk(1,"querybuf: Wrong type.\n");
 649                 return -EINVAL;
 650         }
 651         if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME)) {
 652                 dprintk(1,"querybuf: index out of range.\n");
 653                 return -EINVAL;
 654         }
 655         if (unlikely(NULL == q->bufs[b->index])) {
 656                 dprintk(1,"querybuf: buffer is null.\n");
 657                 return -EINVAL;
 658         }
 659         videobuf_status(b,q->bufs[b->index],q->type);
 660         return 0;
 661 }
 662
 663 int
 664 videobuf_qbuf(struct videobuf_queue *q,
 665               struct v4l2_buffer *b)
 666 {
 667         struct videobuf_buffer *buf;
 668         enum v4l2_field field;
 669         unsigned long flags=0;
 670         int retval;
 671
 672         mutex_lock(&q->lock);
 673         retval = -EBUSY;
 674         if (q->reading) {
 675                 dprintk(1,"qbuf: Reading running...\n");
 676                 goto done;
 677         }
 678         retval = -EINVAL;
 679         if (b->type != q->type) {
 680                 dprintk(1,"qbuf: Wrong type.\n");
 681                 goto done;
 682         }
 683         if (b->index < 0 || b->index >= VIDEO_MAX_FRAME) {
 684                 dprintk(1,"qbuf: index out of range.\n");
 685                 goto done;
 686         }
 687         buf = q->bufs[b->index];
 688         if (NULL == buf) {
 689                 dprintk(1,"qbuf: buffer is null.\n");
 690                 goto done;
 691         }
 692         MAGIC_CHECK(buf->magic,MAGIC_BUFFER);
 693         if (buf->memory != b->memory) {
 694                 dprintk(1,"qbuf: memory type is wrong.\n");
 695                 goto done;
 696         }
 697         if (buf->state == STATE_QUEUED ||
 698             buf->state == STATE_ACTIVE) {
 699                 dprintk(1,"qbuf: buffer is already queued or active.\n");
 700                 goto done;
 701         }
 702
 703         if (b->flags & V4L2_BUF_FLAG_INPUT) {
 704                 if (b->input >= q->inputs) {
 705                         dprintk(1,"qbuf: wrong input.\n");
 706                         goto done;
 707                 }
 708                 buf->input = b->input;
 709         } else {
 710                 buf->input = UNSET;
 711         }
 712
 713         switch (b->memory) {
 714         case V4L2_MEMORY_MMAP:
 715                 if (0 == buf->baddr) {
 716                         dprintk(1,"qbuf: mmap requested but buffer addr is zero!\n");
 717                         goto done;
 718                 }
 719                 break;
 720         case V4L2_MEMORY_USERPTR:
 721                 if (b->length < buf->bsize) {
 722                         dprintk(1,"qbuf: buffer length is not enough\n");
 723                         goto done;
 724                 }
 725                 if (STATE_NEEDS_INIT != buf->state && buf->baddr != b->m.userptr)
 726                         q->ops->buf_release(q,buf);
 727                 buf->baddr = b->m.userptr;
 728                 break;
 729         case V4L2_MEMORY_OVERLAY:
 730                 buf->boff = b->m.offset;
 731                 break;
 732         default:
 733                 dprintk(1,"qbuf: wrong memory type\n");
 734                 goto done;
 735         }
 736
 737         dprintk(1,"qbuf: requesting next field\n");
 738         field = videobuf_next_field(q);
 739         retval = q->ops->buf_prepare(q,buf,field);
 740         if (0 != retval) {
 741                 dprintk(1,"qbuf: buffer_prepare returned %d\n",retval);
 742                 goto done;
 743         }
 744
 745         list_add_tail(&buf->stream,&q->stream);
 746         if (q->streaming) {
 747                 if (q->irqlock)
 748                         spin_lock_irqsave(q->irqlock,flags);
 749                 q->ops->buf_queue(q,buf);
 750                 if (q->irqlock)
 751                         spin_unlock_irqrestore(q->irqlock,flags);
 752         }
 753         dprintk(1,"qbuf: succeded\n");
 754         retval = 0;
 755
 756  done:
 757         mutex_unlock(&q->lock);
 758         return retval;
 759 }
 760
 761 int
 762 videobuf_dqbuf(struct videobuf_queue *q,
 763                struct v4l2_buffer *b, int nonblocking)
 764 {
 765         struct videobuf_buffer *buf;
 766         int retval;
 767
 768         mutex_lock(&q->lock);
 769         retval = -EBUSY;
 770         if (q->reading) {
 771                 dprintk(1,"dqbuf: Reading running...\n");
 772                 goto done;
 773         }
 774         retval = -EINVAL;
 775         if (b->type != q->type) {
 776                 dprintk(1,"dqbuf: Wrong type.\n");
 777                 goto done;
 778         }
 779         if (list_empty(&q->stream)) {
 780                 dprintk(1,"dqbuf: stream running\n");
 781                 goto done;
 782         }
 783         buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
 784         retval = videobuf_waiton(buf, nonblocking, 1);
 785         if (retval < 0) {
 786                 dprintk(1,"dqbuf: waiton returned %d\n",retval);
 787                 goto done;
 788         }
 789         switch (buf->state) {
 790         case STATE_ERROR:
 791                 dprintk(1,"dqbuf: state is error\n");
 792                 retval = -EIO;
 793                 videobuf_dma_sync(q,&buf->dma);
 794                 buf->state = STATE_IDLE;
 795                 break;
 796         case STATE_DONE:
 797                 dprintk(1,"dqbuf: state is done\n");
 798                 videobuf_dma_sync(q,&buf->dma);
 799                 buf->state = STATE_IDLE;
 800                 break;
 801         default:
 802                 dprintk(1,"dqbuf: state invalid\n");
 803                 retval = -EINVAL;
 804                 goto done;
 805         }
 806         list_del(&buf->stream);
 807         memset(b,0,sizeof(*b));
 808         videobuf_status(b,buf,q->type);
 809
 810  done:
 811         mutex_unlock(&q->lock);
 812         return retval;
 813 }
 814
 815 int videobuf_streamon(struct videobuf_queue *q)
 816 {
 817         struct videobuf_buffer *buf;
 818         struct list_head *list;
 819         unsigned long flags=0;
 820         int retval;
 821
 822         mutex_lock(&q->lock);
 823         retval = -EBUSY;
 824         if (q->reading)
 825                 goto done;
 826         retval = 0;
 827         if (q->streaming)
 828                 goto done;
 829         q->streaming = 1;
 830         if (q->irqlock)
 831                 spin_lock_irqsave(q->irqlock,flags);
 832         list_for_each(list,&q->stream) {
 833                 buf = list_entry(list, struct videobuf_buffer, stream);
 834                 if (buf->state == STATE_PREPARED)
 835                         q->ops->buf_queue(q,buf);
 836         }
 837         if (q->irqlock)
 838                 spin_unlock_irqrestore(q->irqlock,flags);
 839
 840  done:
 841         mutex_unlock(&q->lock);
 842         return retval;
 843 }
 844
 845 int videobuf_streamoff(struct videobuf_queue *q)
 846 {
 847         int retval = -EINVAL;
 848
 849         mutex_lock(&q->lock);
 850         if (!q->streaming)
 851                 goto done;
 852         videobuf_queue_cancel(q);
 853         q->streaming = 0;
 854         retval = 0;
 855
 856  done:
 857         mutex_unlock(&q->lock);
 858         return retval;
 859 }
 860
 861 static ssize_t
 862 videobuf_read_zerocopy(struct videobuf_queue *q, char __user *data,
 863                        size_t count, loff_t *ppos)
 864 {
 865         enum v4l2_field field;
 866         unsigned long flags=0;
 867         int retval;
 868
 869         /* setup stuff */
 870         q->read_buf = videobuf_alloc(q->msize);
 871         if (NULL == q->read_buf)
 872                 return -ENOMEM;
 873
 874         q->read_buf->memory = V4L2_MEMORY_USERPTR;
 875         q->read_buf->baddr  = (unsigned long)data;
 876         q->read_buf->bsize  = count;
 877         field = videobuf_next_field(q);
 878         retval = q->ops->buf_prepare(q,q->read_buf,field);
 879         if (0 != retval)
 880                 goto done;
 881
 882         /* start capture & wait */
 883         if (q->irqlock)
 884                 spin_lock_irqsave(q->irqlock,flags);
 885         q->ops->buf_queue(q,q->read_buf);
 886         if (q->irqlock)
 887                 spin_unlock_irqrestore(q->irqlock,flags);
 888         retval = videobuf_waiton(q->read_buf,0,0);
 889         if (0 == retval) {
 890                 videobuf_dma_sync(q,&q->read_buf->dma);
 891                 if (STATE_ERROR == q->read_buf->state)
 892                         retval = -EIO;
 893                 else
 894                         retval = q->read_buf->size;
 895         }
 896
 897  done:
 898         /* cleanup */
 899         q->ops->buf_release(q,q->read_buf);
 900         kfree(q->read_buf);
 901         q->read_buf = NULL;
 902         return retval;
 903 }
 904
 905 ssize_t videobuf_read_one(struct videobuf_queue *q,
 906                           char __user *data, size_t count, loff_t *ppos,
 907                           int nonblocking)
 908 {
 909         enum v4l2_field field;
 910         unsigned long flags=0;
 911         unsigned size, nbufs, bytes;
 912         int retval;
 913
 914         mutex_lock(&q->lock);
 915
 916         nbufs = 1; size = 0;
 917         q->ops->buf_setup(q,&nbufs,&size);
 918         if (NULL == q->read_buf  &&
 919             count >= size        &&
 920             !nonblocking) {
 921                 retval = videobuf_read_zerocopy(q,data,count,ppos);
 922                 if (retval >= 0  ||  retval == -EIO)
 923                         /* ok, all done */
 924                         goto done;
 925                 /* fallback to kernel bounce buffer on failures */
 926         }
 927
 928         if (NULL == q->read_buf) {
 929                 /* need to capture a new frame */
 930                 retval = -ENOMEM;
 931                 q->read_buf = videobuf_alloc(q->msize);
 932                 dprintk(1,"video alloc=0x%p\n", q->read_buf);
 933                 if (NULL == q->read_buf)
 934                         goto done;
 935                 q->read_buf->memory = V4L2_MEMORY_USERPTR;
 936                 q->read_buf->bsize = count; /* preferred size */
 937                 field = videobuf_next_field(q);
 938                 retval = q->ops->buf_prepare(q,q->read_buf,field);
 939                 if (0 != retval) {
 940                         kfree (q->read_buf);
 941                         q->read_buf = NULL;
 942                         goto done;
 943                 }
 944                 if (q->irqlock)
 945                         spin_lock_irqsave(q->irqlock,flags);
 946                 q->ops->buf_queue(q,q->read_buf);
 947                 if (q->irqlock)
 948                         spin_unlock_irqrestore(q->irqlock,flags);
 949                 q->read_off = 0;
 950         }
 951
 952         /* wait until capture is done */
 953         retval = videobuf_waiton(q->read_buf, nonblocking, 1);
 954         if (0 != retval)
 955                 goto done;
 956         videobuf_dma_sync(q,&q->read_buf->dma);
 957
 958         if (STATE_ERROR == q->read_buf->state) {
 959                 /* catch I/O errors */
 960                 q->ops->buf_release(q,q->read_buf);
 961                 kfree(q->read_buf);
 962                 q->read_buf = NULL;
 963                 retval = -EIO;
 964                 goto done;
 965         }
 966
 967         /* copy to userspace */
 968         bytes = count;
 969         if (bytes > q->read_buf->size - q->read_off)
 970                 bytes = q->read_buf->size - q->read_off;
 971         retval = -EFAULT;
 972         if (copy_to_user(data, q->read_buf->dma.vmalloc+q->read_off, bytes))
 973                 goto done;
 974
 975         retval = bytes;
 976         q->read_off += bytes;
 977         if (q->read_off == q->read_buf->size) {
 978                 /* all data copied, cleanup */
 979                 q->ops->buf_release(q,q->read_buf);
 980                 kfree(q->read_buf);
 981                 q->read_buf = NULL;
 982         }
 983
 984  done:
 985         mutex_unlock(&q->lock);
 986         return retval;
 987 }
 988
 989 int videobuf_read_start(struct videobuf_queue *q)
 990 {
 991         enum v4l2_field field;
 992         unsigned long flags=0;
 993         int count = 0, size = 0;
 994         int err, i;
 995
 996         q->ops->buf_setup(q,&count,&size);
 997         if (count < 2)
 998                 count = 2;
 999         if (count > VIDEO_MAX_FRAME)
1000                 count = VIDEO_MAX_FRAME;
1001         size = PAGE_ALIGN(size);
1002
1003         err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
1004         if (err)
1005                 return err;
1006         for (i = 0; i < count; i++) {
1007                 field = videobuf_next_field(q);
1008                 err = q->ops->buf_prepare(q,q->bufs[i],field);
1009                 if (err)
1010                         return err;
1011                 list_add_tail(&q->bufs[i]->stream, &q->stream);
1012         }
1013         if (q->irqlock)
1014                 spin_lock_irqsave(q->irqlock,flags);
1015         for (i = 0; i < count; i++)
1016                 q->ops->buf_queue(q,q->bufs[i]);
1017         if (q->irqlock)
1018                 spin_unlock_irqrestore(q->irqlock,flags);
1019         q->reading = 1;
1020         return 0;
1021 }
1022
1023 void videobuf_read_stop(struct videobuf_queue *q)
1024 {
1025         int i;
1026
1027         videobuf_queue_cancel(q);
1028         videobuf_mmap_free(q);
1029         INIT_LIST_HEAD(&q->stream);
1030         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1031                 if (NULL == q->bufs[i])
1032                         continue;
1033                 kfree(q->bufs[i]);
1034                 q->bufs[i] = NULL;
1035         }
1036         q->read_buf = NULL;
1037         q->reading  = 0;
1038 }
1039
1040 ssize_t videobuf_read_stream(struct videobuf_queue *q,
1041                              char __user *data, size_t count, loff_t *ppos,
1042                              int vbihack, int nonblocking)
1043 {
1044         unsigned int *fc, bytes;
1045         int err, retval;
1046         unsigned long flags=0;
1047
1048         dprintk(2,"%s\n",__FUNCTION__);
1049         mutex_lock(&q->lock);
1050         retval = -EBUSY;
1051         if (q->streaming)
1052                 goto done;
1053         if (!q->reading) {
1054                 retval = videobuf_read_start(q);
1055                 if (retval < 0)
1056                         goto done;
1057         }
1058
1059         retval = 0;
1060         while (count > 0) {
1061                 /* get / wait for data */
1062                 if (NULL == q->read_buf) {
1063                         q->read_buf = list_entry(q->stream.next,
1064                                                  struct videobuf_buffer,
1065                                                  stream);
1066                         list_del(&q->read_buf->stream);
1067                         q->read_off = 0;
1068                 }
1069                 err = videobuf_waiton(q->read_buf, nonblocking, 1);
1070                 if (err < 0) {
1071                         if (0 == retval)
1072                                 retval = err;
1073                         break;
1074                 }
1075
1076                 if (q->read_buf->state == STATE_DONE) {
1077                         if (vbihack) {
1078                                 /* dirty, undocumented hack -- pass the frame counter
1079                                  * within the last four bytes of each vbi data block.
1080                                  * We need that one to maintain backward compatibility
1081                                  * to all vbi decoding software out there ... */
1082                                 fc  = (unsigned int*)q->read_buf->dma.vmalloc;
1083                                 fc += (q->read_buf->size>>2) -1;
1084                                 *fc = q->read_buf->field_count >> 1;
1085                                 dprintk(1,"vbihack: %d\n",*fc);
1086                         }
1087
1088                         /* copy stuff */
1089                         bytes = count;
1090                         if (bytes > q->read_buf->size - q->read_off)
1091                                 bytes = q->read_buf->size - q->read_off;
1092                         if (copy_to_user(data + retval,
1093                                          q->read_buf->dma.vmalloc + q->read_off,
1094                                          bytes)) {
1095                                 if (0 == retval)
1096                                         retval = -EFAULT;
1097                                 break;
1098                         }
1099                         count       -= bytes;
1100                         retval      += bytes;
1101                         q->read_off += bytes;
1102                 } else {
1103                         /* some error */
1104                         q->read_off = q->read_buf->size;
1105                         if (0 == retval)
1106                                 retval = -EIO;
1107                 }
1108
1109                 /* requeue buffer when done with copying */
1110                 if (q->read_off == q->read_buf->size) {
1111                         list_add_tail(&q->read_buf->stream,
1112                                       &q->stream);
1113                         if (q->irqlock)
1114                                 spin_lock_irqsave(q->irqlock,flags);
1115                         q->ops->buf_queue(q,q->read_buf);
1116                         if (q->irqlock)
1117                                 spin_unlock_irqrestore(q->irqlock,flags);
1118                         q->read_buf = NULL;
1119                 }
1120                 if (retval < 0)
1121                         break;
1122         }
1123
1124  done:
1125         mutex_unlock(&q->lock);
1126         return retval;
1127 }
1128
1129 unsigned int videobuf_poll_stream(struct file *file,
1130                                   struct videobuf_queue *q,
1131                                   poll_table *wait)
1132 {
1133         struct videobuf_buffer *buf = NULL;
1134         unsigned int rc = 0;
1135
1136         mutex_lock(&q->lock);
1137         if (q->streaming) {
1138                 if (!list_empty(&q->stream))
1139                         buf = list_entry(q->stream.next,
1140                                          struct videobuf_buffer, stream);
1141         } else {
1142                 if (!q->reading)
1143                         videobuf_read_start(q);
1144                 if (!q->reading) {
1145                         rc = POLLERR;
1146                 } else if (NULL == q->read_buf) {
1147                         q->read_buf = list_entry(q->stream.next,
1148                                                  struct videobuf_buffer,
1149                                                  stream);
1150                         list_del(&q->read_buf->stream);
1151                         q->read_off = 0;
1152                 }
1153                 buf = q->read_buf;
1154         }
1155         if (!buf)
1156                 rc = POLLERR;
1157
1158         if (0 == rc) {
1159                 poll_wait(file, &buf->done, wait);
1160                 if (buf->state == STATE_DONE ||
1161                     buf->state == STATE_ERROR)
1162                         rc = POLLIN|POLLRDNORM;
1163         }
1164         mutex_unlock(&q->lock);
1165         return rc;
1166 }
1167
1168 /* --------------------------------------------------------------------- */
1169
1170 static void
1171 videobuf_vm_open(struct vm_area_struct *vma)
1172 {
1173         struct videobuf_mapping *map = vma->vm_private_data;
1174
1175         dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
1176                 map->count,vma->vm_start,vma->vm_end);
1177         map->count++;
1178 }
1179
1180 static void
1181 videobuf_vm_close(struct vm_area_struct *vma)
1182 {
1183         struct videobuf_mapping *map = vma->vm_private_data;
1184         struct videobuf_queue *q = map->q;
1185         int i;
1186
1187         dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
1188                 map->count,vma->vm_start,vma->vm_end);
1189
1190         map->count--;
1191         if (0 == map->count) {
1192                 dprintk(1,"munmap %p q=%p\n",map,q);
1193                 mutex_lock(&q->lock);
1194                 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1195                         if (NULL == q->bufs[i])
1196                                 continue;
1197                         if (q->bufs[i])
1198                                 ;
1199                         if (q->bufs[i]->map != map)
1200                                 continue;
1201                         q->bufs[i]->map   = NULL;
1202                         q->bufs[i]->baddr = 0;
1203                         q->ops->buf_release(q,q->bufs[i]);
1204                 }
1205                 mutex_unlock(&q->lock);
1206                 kfree(map);
1207         }
1208         return;
1209 }
1210
1211 /*
1212  * Get a anonymous page for the mapping.  Make sure we can DMA to that
1213  * memory location with 32bit PCI devices (i.e. don't use highmem for
1214  * now ...).  Bounce buffers don't work very well for the data rates
1215  * video capture has.
1216  */
1217 static struct page*
1218 videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
1219                    int *type)
1220 {
1221         struct page *page;
1222
1223         dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n",
1224                 vaddr,vma->vm_start,vma->vm_end);
1225         if (vaddr > vma->vm_end)
1226                 return NOPAGE_SIGBUS;
1227         page = alloc_page(GFP_USER);
1228         if (!page)
1229                 return NOPAGE_OOM;
1230         clear_user_page(page_address(page), vaddr, page);
1231         if (type)
1232                 *type = VM_FAULT_MINOR;
1233         return page;
1234 }
1235
1236 static struct vm_operations_struct videobuf_vm_ops =
1237 {
1238         .open     = videobuf_vm_open,
1239         .close    = videobuf_vm_close,
1240         .nopage   = videobuf_vm_nopage,
1241 };
1242
1243 int videobuf_mmap_setup(struct videobuf_queue *q,
1244                         unsigned int bcount, unsigned int bsize,
1245                         enum v4l2_memory memory)
1246 {
1247         unsigned int i;
1248         int err;
1249
1250         err = videobuf_mmap_free(q);
1251         if (0 != err)
1252                 return err;
1253
1254         for (i = 0; i < bcount; i++) {
1255                 q->bufs[i] = videobuf_alloc(q->msize);
1256                 q->bufs[i]->i      = i;
1257                 q->bufs[i]->input  = UNSET;
1258                 q->bufs[i]->memory = memory;
1259                 q->bufs[i]->bsize  = bsize;
1260                 switch (memory) {
1261                 case V4L2_MEMORY_MMAP:
1262                         q->bufs[i]->boff  = bsize * i;
1263                         break;
1264                 case V4L2_MEMORY_USERPTR:
1265                 case V4L2_MEMORY_OVERLAY:
1266                         /* nothing */
1267                         break;
1268                 }
1269         }
1270         dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
1271                 bcount,bsize);
1272         return 0;
1273 }
1274
1275 int videobuf_mmap_free(struct videobuf_queue *q)
1276 {
1277         int i;
1278
1279         for (i = 0; i < VIDEO_MAX_FRAME; i++)
1280                 if (q->bufs[i] && q->bufs[i]->map)
1281                         return -EBUSY;
1282         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1283                 if (NULL == q->bufs[i])
1284                         continue;
1285                 q->ops->buf_release(q,q->bufs[i]);
1286                 kfree(q->bufs[i]);
1287                 q->bufs[i] = NULL;
1288         }
1289         return 0;
1290 }
1291
1292 int videobuf_mmap_mapper(struct videobuf_queue *q,
1293                          struct vm_area_struct *vma)
1294 {
1295         struct videobuf_mapping *map;
1296         unsigned int first,last,size,i;
1297         int retval;
1298
1299         mutex_lock(&q->lock);
1300         retval = -EINVAL;
1301         if (!(vma->vm_flags & VM_WRITE)) {
1302                 dprintk(1,"mmap app bug: PROT_WRITE please\n");
1303                 goto done;
1304         }
1305         if (!(vma->vm_flags & VM_SHARED)) {
1306                 dprintk(1,"mmap app bug: MAP_SHARED please\n");
1307                 goto done;
1308         }
1309
1310         /* look for first buffer to map */
1311         for (first = 0; first < VIDEO_MAX_FRAME; first++) {
1312                 if (NULL == q->bufs[first])
1313                         continue;
1314                 if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
1315                         continue;
1316                 if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
1317                         break;
1318         }
1319         if (VIDEO_MAX_FRAME == first) {
1320                 dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
1321                         (vma->vm_pgoff << PAGE_SHIFT));
1322                 goto done;
1323         }
1324
1325         /* look for last buffer to map */
1326         for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
1327                 if (NULL == q->bufs[last])
1328                         continue;
1329                 if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
1330                         continue;
1331                 if (q->bufs[last]->map) {
1332                         retval = -EBUSY;
1333                         goto done;
1334                 }
1335                 size += q->bufs[last]->bsize;
1336                 if (size == (vma->vm_end - vma->vm_start))
1337                         break;
1338         }
1339         if (VIDEO_MAX_FRAME == last) {
1340                 dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n",
1341                         (vma->vm_end - vma->vm_start));
1342                 goto done;
1343         }
1344
1345         /* create mapping + update buffer list */
1346         retval = -ENOMEM;
1347         map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
1348         if (NULL == map)
1349                 goto done;
1350         for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) {
1351                 q->bufs[i]->map   = map;
1352                 q->bufs[i]->baddr = vma->vm_start + size;
1353         }
1354         map->count    = 1;
1355         map->start    = vma->vm_start;
1356         map->end      = vma->vm_end;
1357         map->q        = q;
1358         vma->vm_ops   = &videobuf_vm_ops;
1359         vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
1360         vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
1361         vma->vm_private_data = map;
1362         dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
1363                 map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
1364         retval = 0;
1365
1366  done:
1367         mutex_unlock(&q->lock);
1368         return retval;
1369 }
1370
1371 /* --------------------------------------------------------------------- */
1372
1373 EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
1374
1375 EXPORT_SYMBOL_GPL(videobuf_dma_init);
1376 EXPORT_SYMBOL_GPL(videobuf_dma_init_user);
1377 EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel);
1378 EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay);
1379 EXPORT_SYMBOL_GPL(videobuf_dma_map);
1380 EXPORT_SYMBOL_GPL(videobuf_dma_sync);
1381 EXPORT_SYMBOL_GPL(videobuf_dma_unmap);
1382 EXPORT_SYMBOL_GPL(videobuf_dma_free);
1383
1384 EXPORT_SYMBOL_GPL(videobuf_pci_dma_map);
1385 EXPORT_SYMBOL_GPL(videobuf_pci_dma_unmap);
1386
1387 EXPORT_SYMBOL_GPL(videobuf_alloc);
1388 EXPORT_SYMBOL_GPL(videobuf_waiton);
1389 EXPORT_SYMBOL_GPL(videobuf_iolock);
1390
1391 EXPORT_SYMBOL_GPL(videobuf_queue_init);
1392 EXPORT_SYMBOL_GPL(videobuf_queue_cancel);
1393 EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
1394
1395 EXPORT_SYMBOL_GPL(videobuf_next_field);
1396 EXPORT_SYMBOL_GPL(videobuf_status);
1397 EXPORT_SYMBOL_GPL(videobuf_reqbufs);
1398 EXPORT_SYMBOL_GPL(videobuf_querybuf);
1399 EXPORT_SYMBOL_GPL(videobuf_qbuf);
1400 EXPORT_SYMBOL_GPL(videobuf_dqbuf);
1401 EXPORT_SYMBOL_GPL(videobuf_streamon);
1402 EXPORT_SYMBOL_GPL(videobuf_streamoff);
1403
1404 EXPORT_SYMBOL_GPL(videobuf_read_start);
1405 EXPORT_SYMBOL_GPL(videobuf_read_stop);
1406 EXPORT_SYMBOL_GPL(videobuf_read_stream);
1407 EXPORT_SYMBOL_GPL(videobuf_read_one);
1408 EXPORT_SYMBOL_GPL(videobuf_poll_stream);
1409
1410 EXPORT_SYMBOL_GPL(videobuf_mmap_setup);
1411 EXPORT_SYMBOL_GPL(videobuf_mmap_free);
1412 EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);
1413
1414 /*
1415  * Local variables:
1416  * c-basic-offset: 8
1417  * End:
1418  */