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                 /*
 369                  * Using a double cast to avoid compiler warnings when
 370                  * building for PAE. Compiler doesn't like direct casting
 371                  * of a 32 bit ptr to 64 bit integer.
 372                  */
 373                 bus   = (dma_addr_t)(unsigned long)fbuf->base + vb->boff;
 374                 pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
 375                 err = videobuf_dma_init_overlay(&vb->dma,PCI_DMA_FROMDEVICE,
 376                                                 bus, pages);
 377                 if (0 != err)
 378                         return err;
 379                 break;
 380         default:
 381                 BUG();
 382         }
 383         err = videobuf_dma_map(q,&vb->dma);
 384         if (0 != err)
 385                 return err;
 386
 387         return 0;
 388 }
 389
 390 /* --------------------------------------------------------------------- */
 391
 392 void videobuf_queue_pci(struct videobuf_queue* q)
 393 {
 394         /* If not specified, defaults to PCI map sg */
 395         if (!q->ops->vb_map_sg)
 396                 q->ops->vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 397
 398         if (!q->ops->vb_dma_sync_sg)
 399                 q->ops->vb_dma_sync_sg=(vb_map_sg_t *)pci_dma_sync_sg_for_cpu;
 400         if (!q->ops->vb_unmap_sg)
 401                 q->ops->vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 402 }
 403
 404 int videobuf_pci_dma_map(struct pci_dev *pci,struct videobuf_dmabuf *dma)
 405 {
 406         struct videobuf_queue q;
 407         struct videobuf_queue_ops qops;
 408
 409         q.dev=pci;
 410         qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 411         qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 412         q.ops = &qops;
 413
 414         return (videobuf_dma_map(&q,dma));
 415 }
 416
 417 int videobuf_pci_dma_unmap(struct pci_dev *pci,struct videobuf_dmabuf *dma)
 418 {
 419         struct videobuf_queue q;
 420         struct videobuf_queue_ops qops;
 421
 422         q.dev=pci;
 423         qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 424         qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 425         q.ops = &qops;
 426
 427         return (videobuf_dma_unmap(&q,dma));
 428 }
 429
 430 void videobuf_queue_init(struct videobuf_queue* q,
 431                          struct videobuf_queue_ops *ops,
 432                          void *dev,
 433                          spinlock_t *irqlock,
 434                          enum v4l2_buf_type type,
 435                          enum v4l2_field field,
 436                          unsigned int msize,
 437                          void *priv)
 438 {
 439         memset(q,0,sizeof(*q));
 440         q->irqlock = irqlock;
 441         q->dev     = dev;
 442         q->type    = type;
 443         q->field   = field;
 444         q->msize   = msize;
 445         q->ops     = ops;
 446         q->priv_data = priv;
 447
 448         videobuf_queue_pci(q);
 449
 450         mutex_init(&q->lock);
 451         INIT_LIST_HEAD(&q->stream);
 452 }
 453
 454 int
 455 videobuf_queue_is_busy(struct videobuf_queue *q)
 456 {
 457         int i;
 458
 459         if (q->streaming) {
 460                 dprintk(1,"busy: streaming active\n");
 461                 return 1;
 462         }
 463         if (q->reading) {
 464                 dprintk(1,"busy: pending read #1\n");
 465                 return 1;
 466         }
 467         if (q->read_buf) {
 468                 dprintk(1,"busy: pending read #2\n");
 469                 return 1;
 470         }
 471         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 472                 if (NULL == q->bufs[i])
 473                         continue;
 474                 if (q->bufs[i]->map) {
 475                         dprintk(1,"busy: buffer #%d mapped\n",i);
 476                         return 1;
 477                 }
 478                 if (q->bufs[i]->state == STATE_QUEUED) {
 479                         dprintk(1,"busy: buffer #%d queued\n",i);
 480                         return 1;
 481                 }
 482                 if (q->bufs[i]->state == STATE_ACTIVE) {
 483                         dprintk(1,"busy: buffer #%d avtive\n",i);
 484                         return 1;
 485                 }
 486         }
 487         return 0;
 488 }
 489
 490 void
 491 videobuf_queue_cancel(struct videobuf_queue *q)
 492 {
 493         unsigned long flags=0;
 494         int i;
 495
 496         /* remove queued buffers from list */
 497         if (q->irqlock)
 498                 spin_lock_irqsave(q->irqlock,flags);
 499         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 500                 if (NULL == q->bufs[i])
 501                         continue;
 502                 if (q->bufs[i]->state == STATE_QUEUED) {
 503                         list_del(&q->bufs[i]->queue);
 504                         q->bufs[i]->state = STATE_ERROR;
 505                 }
 506         }
 507         if (q->irqlock)
 508                 spin_unlock_irqrestore(q->irqlock,flags);
 509
 510         /* free all buffers + clear queue */
 511         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 512                 if (NULL == q->bufs[i])
 513                         continue;
 514                 q->ops->buf_release(q,q->bufs[i]);
 515         }
 516         INIT_LIST_HEAD(&q->stream);
 517 }
 518
 519 /* --------------------------------------------------------------------- */
 520
 521 enum v4l2_field
 522 videobuf_next_field(struct videobuf_queue *q)
 523 {
 524         enum v4l2_field field = q->field;
 525
 526         BUG_ON(V4L2_FIELD_ANY == field);
 527
 528         if (V4L2_FIELD_ALTERNATE == field) {
 529                 if (V4L2_FIELD_TOP == q->last) {
 530                         field   = V4L2_FIELD_BOTTOM;
 531                         q->last = V4L2_FIELD_BOTTOM;
 532                 } else {
 533                         field   = V4L2_FIELD_TOP;
 534                         q->last = V4L2_FIELD_TOP;
 535                 }
 536         }
 537         return field;
 538 }
 539
 540 void
 541 videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb,
 542                 enum v4l2_buf_type type)
 543 {
 544         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 545
 546         b->index    = vb->i;
 547         b->type     = type;
 548
 549         b->memory   = vb->memory;
 550         switch (b->memory) {
 551         case V4L2_MEMORY_MMAP:
 552                 b->m.offset  = vb->boff;
 553                 b->length    = vb->bsize;
 554                 break;
 555         case V4L2_MEMORY_USERPTR:
 556                 b->m.userptr = vb->baddr;
 557                 b->length    = vb->bsize;
 558                 break;
 559         case V4L2_MEMORY_OVERLAY:
 560                 b->m.offset  = vb->boff;
 561                 break;
 562         }
 563
 564         b->flags    = 0;
 565         if (vb->map)
 566                 b->flags |= V4L2_BUF_FLAG_MAPPED;
 567
 568         switch (vb->state) {
 569         case STATE_PREPARED:
 570         case STATE_QUEUED:
 571         case STATE_ACTIVE:
 572                 b->flags |= V4L2_BUF_FLAG_QUEUED;
 573                 break;
 574         case STATE_DONE:
 575         case STATE_ERROR:
 576                 b->flags |= V4L2_BUF_FLAG_DONE;
 577                 break;
 578         case STATE_NEEDS_INIT:
 579         case STATE_IDLE:
 580                 /* nothing */
 581                 break;
 582         }
 583
 584         if (vb->input != UNSET) {
 585                 b->flags |= V4L2_BUF_FLAG_INPUT;
 586                 b->input  = vb->input;
 587         }
 588
 589         b->field     = vb->field;
 590         b->timestamp = vb->ts;
 591         b->bytesused = vb->size;
 592         b->sequence  = vb->field_count >> 1;
 593 }
 594
 595 int
 596 videobuf_reqbufs(struct videobuf_queue *q,
 597                  struct v4l2_requestbuffers *req)
 598 {
 599         unsigned int size,count;
 600         int retval;
 601
 602         if (req->type != q->type) {
 603                 dprintk(1,"reqbufs: queue type invalid\n");
 604                 return -EINVAL;
 605         }
 606         if (req->count < 1) {
 607                 dprintk(1,"reqbufs: count invalid (%d)\n",req->count);
 608                 return -EINVAL;
 609         }
 610         if (req->memory != V4L2_MEMORY_MMAP     &&
 611             req->memory != V4L2_MEMORY_USERPTR  &&
 612             req->memory != V4L2_MEMORY_OVERLAY) {
 613                 dprintk(1,"reqbufs: memory type invalid\n");
 614                 return -EINVAL;
 615         }
 616
 617         if (q->streaming) {
 618                 dprintk(1,"reqbufs: streaming already exists\n");
 619                 return -EBUSY;
 620         }
 621         if (!list_empty(&q->stream)) {
 622                 dprintk(1,"reqbufs: stream running\n");
 623                 return -EBUSY;
 624         }
 625
 626         mutex_lock(&q->lock);
 627         count = req->count;
 628         if (count > VIDEO_MAX_FRAME)
 629                 count = VIDEO_MAX_FRAME;
 630         size = 0;
 631         q->ops->buf_setup(q,&count,&size);
 632         size = PAGE_ALIGN(size);
 633         dprintk(1,"reqbufs: bufs=%d, size=0x%x [%d pages total]\n",
 634                 count, size, (count*size)>>PAGE_SHIFT);
 635
 636         retval = videobuf_mmap_setup(q,count,size,req->memory);
 637         if (retval < 0) {
 638                 dprintk(1,"reqbufs: mmap setup returned %d\n",retval);
 639                 goto done;
 640         }
 641
 642         req->count = count;
 643
 644  done:
 645         mutex_unlock(&q->lock);
 646         return retval;
 647 }
 648
 649 int
 650 videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b)
 651 {
 652         if (unlikely(b->type != q->type)) {
 653                 dprintk(1,"querybuf: Wrong type.\n");
 654                 return -EINVAL;
 655         }
 656         if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME)) {
 657                 dprintk(1,"querybuf: index out of range.\n");
 658                 return -EINVAL;
 659         }
 660         if (unlikely(NULL == q->bufs[b->index])) {
 661                 dprintk(1,"querybuf: buffer is null.\n");
 662                 return -EINVAL;
 663         }
 664         videobuf_status(b,q->bufs[b->index],q->type);
 665         return 0;
 666 }
 667
 668 int
 669 videobuf_qbuf(struct videobuf_queue *q,
 670               struct v4l2_buffer *b)
 671 {
 672         struct videobuf_buffer *buf;
 673         enum v4l2_field field;
 674         unsigned long flags=0;
 675         int retval;
 676
 677         mutex_lock(&q->lock);
 678         retval = -EBUSY;
 679         if (q->reading) {
 680                 dprintk(1,"qbuf: Reading running...\n");
 681                 goto done;
 682         }
 683         retval = -EINVAL;
 684         if (b->type != q->type) {
 685                 dprintk(1,"qbuf: Wrong type.\n");
 686                 goto done;
 687         }
 688         if (b->index < 0 || b->index >= VIDEO_MAX_FRAME) {
 689                 dprintk(1,"qbuf: index out of range.\n");
 690                 goto done;
 691         }
 692         buf = q->bufs[b->index];
 693         if (NULL == buf) {
 694                 dprintk(1,"qbuf: buffer is null.\n");
 695                 goto done;
 696         }
 697         MAGIC_CHECK(buf->magic,MAGIC_BUFFER);
 698         if (buf->memory != b->memory) {
 699                 dprintk(1,"qbuf: memory type is wrong.\n");
 700                 goto done;
 701         }
 702         if (buf->state == STATE_QUEUED ||
 703             buf->state == STATE_ACTIVE) {
 704                 dprintk(1,"qbuf: buffer is already queued or active.\n");
 705                 goto done;
 706         }
 707
 708         if (b->flags & V4L2_BUF_FLAG_INPUT) {
 709                 if (b->input >= q->inputs) {
 710                         dprintk(1,"qbuf: wrong input.\n");
 711                         goto done;
 712                 }
 713                 buf->input = b->input;
 714         } else {
 715                 buf->input = UNSET;
 716         }
 717
 718         switch (b->memory) {
 719         case V4L2_MEMORY_MMAP:
 720                 if (0 == buf->baddr) {
 721                         dprintk(1,"qbuf: mmap requested but buffer addr is zero!\n");
 722                         goto done;
 723                 }
 724                 break;
 725         case V4L2_MEMORY_USERPTR:
 726                 if (b->length < buf->bsize) {
 727                         dprintk(1,"qbuf: buffer length is not enough\n");
 728                         goto done;
 729                 }
 730                 if (STATE_NEEDS_INIT != buf->state && buf->baddr != b->m.userptr)
 731                         q->ops->buf_release(q,buf);
 732                 buf->baddr = b->m.userptr;
 733                 break;
 734         case V4L2_MEMORY_OVERLAY:
 735                 buf->boff = b->m.offset;
 736                 break;
 737         default:
 738                 dprintk(1,"qbuf: wrong memory type\n");
 739                 goto done;
 740         }
 741
 742         dprintk(1,"qbuf: requesting next field\n");
 743         field = videobuf_next_field(q);
 744         retval = q->ops->buf_prepare(q,buf,field);
 745         if (0 != retval) {
 746                 dprintk(1,"qbuf: buffer_prepare returned %d\n",retval);
 747                 goto done;
 748         }
 749
 750         list_add_tail(&buf->stream,&q->stream);
 751         if (q->streaming) {
 752                 if (q->irqlock)
 753                         spin_lock_irqsave(q->irqlock,flags);
 754                 q->ops->buf_queue(q,buf);
 755                 if (q->irqlock)
 756                         spin_unlock_irqrestore(q->irqlock,flags);
 757         }
 758         dprintk(1,"qbuf: succeded\n");
 759         retval = 0;
 760
 761  done:
 762         mutex_unlock(&q->lock);
 763         return retval;
 764 }
 765
 766 int
 767 videobuf_dqbuf(struct videobuf_queue *q,
 768                struct v4l2_buffer *b, int nonblocking)
 769 {
 770         struct videobuf_buffer *buf;
 771         int retval;
 772
 773         mutex_lock(&q->lock);
 774         retval = -EBUSY;
 775         if (q->reading) {
 776                 dprintk(1,"dqbuf: Reading running...\n");
 777                 goto done;
 778         }
 779         retval = -EINVAL;
 780         if (b->type != q->type) {
 781                 dprintk(1,"dqbuf: Wrong type.\n");
 782                 goto done;
 783         }
 784         if (list_empty(&q->stream)) {
 785                 dprintk(1,"dqbuf: stream running\n");
 786                 goto done;
 787         }
 788         buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
 789         retval = videobuf_waiton(buf, nonblocking, 1);
 790         if (retval < 0) {
 791                 dprintk(1,"dqbuf: waiton returned %d\n",retval);
 792                 goto done;
 793         }
 794         switch (buf->state) {
 795         case STATE_ERROR:
 796                 dprintk(1,"dqbuf: state is error\n");
 797                 retval = -EIO;
 798                 videobuf_dma_sync(q,&buf->dma);
 799                 buf->state = STATE_IDLE;
 800                 break;
 801         case STATE_DONE:
 802                 dprintk(1,"dqbuf: state is done\n");
 803                 videobuf_dma_sync(q,&buf->dma);
 804                 buf->state = STATE_IDLE;
 805                 break;
 806         default:
 807                 dprintk(1,"dqbuf: state invalid\n");
 808                 retval = -EINVAL;
 809                 goto done;
 810         }
 811         list_del(&buf->stream);
 812         memset(b,0,sizeof(*b));
 813         videobuf_status(b,buf,q->type);
 814
 815  done:
 816         mutex_unlock(&q->lock);
 817         return retval;
 818 }
 819
 820 int videobuf_streamon(struct videobuf_queue *q)
 821 {
 822         struct videobuf_buffer *buf;
 823         struct list_head *list;
 824         unsigned long flags=0;
 825         int retval;
 826
 827         mutex_lock(&q->lock);
 828         retval = -EBUSY;
 829         if (q->reading)
 830                 goto done;
 831         retval = 0;
 832         if (q->streaming)
 833                 goto done;
 834         q->streaming = 1;
 835         if (q->irqlock)
 836                 spin_lock_irqsave(q->irqlock,flags);
 837         list_for_each(list,&q->stream) {
 838                 buf = list_entry(list, struct videobuf_buffer, stream);
 839                 if (buf->state == STATE_PREPARED)
 840                         q->ops->buf_queue(q,buf);
 841         }
 842         if (q->irqlock)
 843                 spin_unlock_irqrestore(q->irqlock,flags);
 844
 845  done:
 846         mutex_unlock(&q->lock);
 847         return retval;
 848 }
 849
 850 int videobuf_streamoff(struct videobuf_queue *q)
 851 {
 852         int retval = -EINVAL;
 853
 854         mutex_lock(&q->lock);
 855         if (!q->streaming)
 856                 goto done;
 857         videobuf_queue_cancel(q);
 858         q->streaming = 0;
 859         retval = 0;
 860
 861  done:
 862         mutex_unlock(&q->lock);
 863         return retval;
 864 }
 865
 866 static ssize_t
 867 videobuf_read_zerocopy(struct videobuf_queue *q, char __user *data,
 868                        size_t count, loff_t *ppos)
 869 {
 870         enum v4l2_field field;
 871         unsigned long flags=0;
 872         int retval;
 873
 874         /* setup stuff */
 875         q->read_buf = videobuf_alloc(q->msize);
 876         if (NULL == q->read_buf)
 877                 return -ENOMEM;
 878
 879         q->read_buf->memory = V4L2_MEMORY_USERPTR;
 880         q->read_buf->baddr  = (unsigned long)data;
 881         q->read_buf->bsize  = count;
 882         field = videobuf_next_field(q);
 883         retval = q->ops->buf_prepare(q,q->read_buf,field);
 884         if (0 != retval)
 885                 goto done;
 886
 887         /* start capture & wait */
 888         if (q->irqlock)
 889                 spin_lock_irqsave(q->irqlock,flags);
 890         q->ops->buf_queue(q,q->read_buf);
 891         if (q->irqlock)
 892                 spin_unlock_irqrestore(q->irqlock,flags);
 893         retval = videobuf_waiton(q->read_buf,0,0);
 894         if (0 == retval) {
 895                 videobuf_dma_sync(q,&q->read_buf->dma);
 896                 if (STATE_ERROR == q->read_buf->state)
 897                         retval = -EIO;
 898                 else
 899                         retval = q->read_buf->size;
 900         }
 901
 902  done:
 903         /* cleanup */
 904         q->ops->buf_release(q,q->read_buf);
 905         kfree(q->read_buf);
 906         q->read_buf = NULL;
 907         return retval;
 908 }
 909
 910 ssize_t videobuf_read_one(struct videobuf_queue *q,
 911                           char __user *data, size_t count, loff_t *ppos,
 912                           int nonblocking)
 913 {
 914         enum v4l2_field field;
 915         unsigned long flags=0;
 916         unsigned size, nbufs, bytes;
 917         int retval;
 918
 919         mutex_lock(&q->lock);
 920
 921         nbufs = 1; size = 0;
 922         q->ops->buf_setup(q,&nbufs,&size);
 923         if (NULL == q->read_buf  &&
 924             count >= size        &&
 925             !nonblocking) {
 926                 retval = videobuf_read_zerocopy(q,data,count,ppos);
 927                 if (retval >= 0  ||  retval == -EIO)
 928                         /* ok, all done */
 929                         goto done;
 930                 /* fallback to kernel bounce buffer on failures */
 931         }
 932
 933         if (NULL == q->read_buf) {
 934                 /* need to capture a new frame */
 935                 retval = -ENOMEM;
 936                 q->read_buf = videobuf_alloc(q->msize);
 937                 dprintk(1,"video alloc=0x%p\n", q->read_buf);
 938                 if (NULL == q->read_buf)
 939                         goto done;
 940                 q->read_buf->memory = V4L2_MEMORY_USERPTR;
 941                 q->read_buf->bsize = count; /* preferred size */
 942                 field = videobuf_next_field(q);
 943                 retval = q->ops->buf_prepare(q,q->read_buf,field);
 944                 if (0 != retval) {
 945                         kfree (q->read_buf);
 946                         q->read_buf = NULL;
 947                         goto done;
 948                 }
 949                 if (q->irqlock)
 950                         spin_lock_irqsave(q->irqlock,flags);
 951                 q->ops->buf_queue(q,q->read_buf);
 952                 if (q->irqlock)
 953                         spin_unlock_irqrestore(q->irqlock,flags);
 954                 q->read_off = 0;
 955         }
 956
 957         /* wait until capture is done */
 958         retval = videobuf_waiton(q->read_buf, nonblocking, 1);
 959         if (0 != retval)
 960                 goto done;
 961         videobuf_dma_sync(q,&q->read_buf->dma);
 962
 963         if (STATE_ERROR == q->read_buf->state) {
 964                 /* catch I/O errors */
 965                 q->ops->buf_release(q,q->read_buf);
 966                 kfree(q->read_buf);
 967                 q->read_buf = NULL;
 968                 retval = -EIO;
 969                 goto done;
 970         }
 971
 972         /* copy to userspace */
 973         bytes = count;
 974         if (bytes > q->read_buf->size - q->read_off)
 975                 bytes = q->read_buf->size - q->read_off;
 976         retval = -EFAULT;
 977         if (copy_to_user(data, q->read_buf->dma.vmalloc+q->read_off, bytes))
 978                 goto done;
 979
 980         retval = bytes;
 981         q->read_off += bytes;
 982         if (q->read_off == q->read_buf->size) {
 983                 /* all data copied, cleanup */
 984                 q->ops->buf_release(q,q->read_buf);
 985                 kfree(q->read_buf);
 986                 q->read_buf = NULL;
 987         }
 988
 989  done:
 990         mutex_unlock(&q->lock);
 991         return retval;
 992 }
 993
 994 int videobuf_read_start(struct videobuf_queue *q)
 995 {
 996         enum v4l2_field field;
 997         unsigned long flags=0;
 998         int count = 0, size = 0;
 999         int err, i;
1000
1001         q->ops->buf_setup(q,&count,&size);
1002         if (count < 2)
1003                 count = 2;
1004         if (count > VIDEO_MAX_FRAME)
1005                 count = VIDEO_MAX_FRAME;
1006         size = PAGE_ALIGN(size);
1007
1008         err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
1009         if (err)
1010                 return err;
1011         for (i = 0; i < count; i++) {
1012                 field = videobuf_next_field(q);
1013                 err = q->ops->buf_prepare(q,q->bufs[i],field);
1014                 if (err)
1015                         return err;
1016                 list_add_tail(&q->bufs[i]->stream, &q->stream);
1017         }
1018         if (q->irqlock)
1019                 spin_lock_irqsave(q->irqlock,flags);
1020         for (i = 0; i < count; i++)
1021                 q->ops->buf_queue(q,q->bufs[i]);
1022         if (q->irqlock)
1023                 spin_unlock_irqrestore(q->irqlock,flags);
1024         q->reading = 1;
1025         return 0;
1026 }
1027
1028 void videobuf_read_stop(struct videobuf_queue *q)
1029 {
1030         int i;
1031
1032         videobuf_queue_cancel(q);
1033         videobuf_mmap_free(q);
1034         INIT_LIST_HEAD(&q->stream);
1035         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1036                 if (NULL == q->bufs[i])
1037                         continue;
1038                 kfree(q->bufs[i]);
1039                 q->bufs[i] = NULL;
1040         }
1041         q->read_buf = NULL;
1042         q->reading  = 0;
1043 }
1044
1045 ssize_t videobuf_read_stream(struct videobuf_queue *q,
1046                              char __user *data, size_t count, loff_t *ppos,
1047                              int vbihack, int nonblocking)
1048 {
1049         unsigned int *fc, bytes;
1050         int err, retval;
1051         unsigned long flags=0;
1052
1053         dprintk(2,"%s\n",__FUNCTION__);
1054         mutex_lock(&q->lock);
1055         retval = -EBUSY;
1056         if (q->streaming)
1057                 goto done;
1058         if (!q->reading) {
1059                 retval = videobuf_read_start(q);
1060                 if (retval < 0)
1061                         goto done;
1062         }
1063
1064         retval = 0;
1065         while (count > 0) {
1066                 /* get / wait for data */
1067                 if (NULL == q->read_buf) {
1068                         q->read_buf = list_entry(q->stream.next,
1069                                                  struct videobuf_buffer,
1070                                                  stream);
1071                         list_del(&q->read_buf->stream);
1072                         q->read_off = 0;
1073                 }
1074                 err = videobuf_waiton(q->read_buf, nonblocking, 1);
1075                 if (err < 0) {
1076                         if (0 == retval)
1077                                 retval = err;
1078                         break;
1079                 }
1080
1081                 if (q->read_buf->state == STATE_DONE) {
1082                         if (vbihack) {
1083                                 /* dirty, undocumented hack -- pass the frame counter
1084                                  * within the last four bytes of each vbi data block.
1085                                  * We need that one to maintain backward compatibility
1086                                  * to all vbi decoding software out there ... */
1087                                 fc  = (unsigned int*)q->read_buf->dma.vmalloc;
1088                                 fc += (q->read_buf->size>>2) -1;
1089                                 *fc = q->read_buf->field_count >> 1;
1090                                 dprintk(1,"vbihack: %d\n",*fc);
1091                         }
1092
1093                         /* copy stuff */
1094                         bytes = count;
1095                         if (bytes > q->read_buf->size - q->read_off)
1096                                 bytes = q->read_buf->size - q->read_off;
1097                         if (copy_to_user(data + retval,
1098                                          q->read_buf->dma.vmalloc + q->read_off,
1099                                          bytes)) {
1100                                 if (0 == retval)
1101                                         retval = -EFAULT;
1102                                 break;
1103                         }
1104                         count       -= bytes;
1105                         retval      += bytes;
1106                         q->read_off += bytes;
1107                 } else {
1108                         /* some error */
1109                         q->read_off = q->read_buf->size;
1110                         if (0 == retval)
1111                                 retval = -EIO;
1112                 }
1113
1114                 /* requeue buffer when done with copying */
1115                 if (q->read_off == q->read_buf->size) {
1116                         list_add_tail(&q->read_buf->stream,
1117                                       &q->stream);
1118                         if (q->irqlock)
1119                                 spin_lock_irqsave(q->irqlock,flags);
1120                         q->ops->buf_queue(q,q->read_buf);
1121                         if (q->irqlock)
1122                                 spin_unlock_irqrestore(q->irqlock,flags);
1123                         q->read_buf = NULL;
1124                 }
1125                 if (retval < 0)
1126                         break;
1127         }
1128
1129  done:
1130         mutex_unlock(&q->lock);
1131         return retval;
1132 }
1133
1134 unsigned int videobuf_poll_stream(struct file *file,
1135                                   struct videobuf_queue *q,
1136                                   poll_table *wait)
1137 {
1138         struct videobuf_buffer *buf = NULL;
1139         unsigned int rc = 0;
1140
1141         mutex_lock(&q->lock);
1142         if (q->streaming) {
1143                 if (!list_empty(&q->stream))
1144                         buf = list_entry(q->stream.next,
1145                                          struct videobuf_buffer, stream);
1146         } else {
1147                 if (!q->reading)
1148                         videobuf_read_start(q);
1149                 if (!q->reading) {
1150                         rc = POLLERR;
1151                 } else if (NULL == q->read_buf) {
1152                         q->read_buf = list_entry(q->stream.next,
1153                                                  struct videobuf_buffer,
1154                                                  stream);
1155                         list_del(&q->read_buf->stream);
1156                         q->read_off = 0;
1157                 }
1158                 buf = q->read_buf;
1159         }
1160         if (!buf)
1161                 rc = POLLERR;
1162
1163         if (0 == rc) {
1164                 poll_wait(file, &buf->done, wait);
1165                 if (buf->state == STATE_DONE ||
1166                     buf->state == STATE_ERROR)
1167                         rc = POLLIN|POLLRDNORM;
1168         }
1169         mutex_unlock(&q->lock);
1170         return rc;
1171 }
1172
1173 /* --------------------------------------------------------------------- */
1174
1175 static void
1176 videobuf_vm_open(struct vm_area_struct *vma)
1177 {
1178         struct videobuf_mapping *map = vma->vm_private_data;
1179
1180         dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
1181                 map->count,vma->vm_start,vma->vm_end);
1182         map->count++;
1183 }
1184
1185 static void
1186 videobuf_vm_close(struct vm_area_struct *vma)
1187 {
1188         struct videobuf_mapping *map = vma->vm_private_data;
1189         struct videobuf_queue *q = map->q;
1190         int i;
1191
1192         dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
1193                 map->count,vma->vm_start,vma->vm_end);
1194
1195         map->count--;
1196         if (0 == map->count) {
1197                 dprintk(1,"munmap %p q=%p\n",map,q);
1198                 mutex_lock(&q->lock);
1199                 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1200                         if (NULL == q->bufs[i])
1201                                 continue;
1202                         if (q->bufs[i])
1203                                 ;
1204                         if (q->bufs[i]->map != map)
1205                                 continue;
1206                         q->bufs[i]->map   = NULL;
1207                         q->bufs[i]->baddr = 0;
1208                         q->ops->buf_release(q,q->bufs[i]);
1209                 }
1210                 mutex_unlock(&q->lock);
1211                 kfree(map);
1212         }
1213         return;
1214 }
1215
1216 /*
1217  * Get a anonymous page for the mapping.  Make sure we can DMA to that
1218  * memory location with 32bit PCI devices (i.e. don't use highmem for
1219  * now ...).  Bounce buffers don't work very well for the data rates
1220  * video capture has.
1221  */
1222 static struct page*
1223 videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
1224                    int *type)
1225 {
1226         struct page *page;
1227
1228         dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n",
1229                 vaddr,vma->vm_start,vma->vm_end);
1230         if (vaddr > vma->vm_end)
1231                 return NOPAGE_SIGBUS;
1232         page = alloc_page(GFP_USER);
1233         if (!page)
1234                 return NOPAGE_OOM;
1235         clear_user_page(page_address(page), vaddr, page);
1236         if (type)
1237                 *type = VM_FAULT_MINOR;
1238         return page;
1239 }
1240
1241 static struct vm_operations_struct videobuf_vm_ops =
1242 {
1243         .open     = videobuf_vm_open,
1244         .close    = videobuf_vm_close,
1245         .nopage   = videobuf_vm_nopage,
1246 };
1247
1248 int videobuf_mmap_setup(struct videobuf_queue *q,
1249                         unsigned int bcount, unsigned int bsize,
1250                         enum v4l2_memory memory)
1251 {
1252         unsigned int i;
1253         int err;
1254
1255         err = videobuf_mmap_free(q);
1256         if (0 != err)
1257                 return err;
1258
1259         for (i = 0; i < bcount; i++) {
1260                 q->bufs[i] = videobuf_alloc(q->msize);
1261                 q->bufs[i]->i      = i;
1262                 q->bufs[i]->input  = UNSET;
1263                 q->bufs[i]->memory = memory;
1264                 q->bufs[i]->bsize  = bsize;
1265                 switch (memory) {
1266                 case V4L2_MEMORY_MMAP:
1267                         q->bufs[i]->boff  = bsize * i;
1268                         break;
1269                 case V4L2_MEMORY_USERPTR:
1270                 case V4L2_MEMORY_OVERLAY:
1271                         /* nothing */
1272                         break;
1273                 }
1274         }
1275         dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
1276                 bcount,bsize);
1277         return 0;
1278 }
1279
1280 int videobuf_mmap_free(struct videobuf_queue *q)
1281 {
1282         int i;
1283
1284         for (i = 0; i < VIDEO_MAX_FRAME; i++)
1285                 if (q->bufs[i] && q->bufs[i]->map)
1286                         return -EBUSY;
1287         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1288                 if (NULL == q->bufs[i])
1289                         continue;
1290                 q->ops->buf_release(q,q->bufs[i]);
1291                 kfree(q->bufs[i]);
1292                 q->bufs[i] = NULL;
1293         }
1294         return 0;
1295 }
1296
1297 int videobuf_mmap_mapper(struct videobuf_queue *q,
1298                          struct vm_area_struct *vma)
1299 {
1300         struct videobuf_mapping *map;
1301         unsigned int first,last,size,i;
1302         int retval;
1303
1304         mutex_lock(&q->lock);
1305         retval = -EINVAL;
1306         if (!(vma->vm_flags & VM_WRITE)) {
1307                 dprintk(1,"mmap app bug: PROT_WRITE please\n");
1308                 goto done;
1309         }
1310         if (!(vma->vm_flags & VM_SHARED)) {
1311                 dprintk(1,"mmap app bug: MAP_SHARED please\n");
1312                 goto done;
1313         }
1314
1315         /* look for first buffer to map */
1316         for (first = 0; first < VIDEO_MAX_FRAME; first++) {
1317                 if (NULL == q->bufs[first])
1318                         continue;
1319                 if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
1320                         continue;
1321                 if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
1322                         break;
1323         }
1324         if (VIDEO_MAX_FRAME == first) {
1325                 dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
1326                         (vma->vm_pgoff << PAGE_SHIFT));
1327                 goto done;
1328         }
1329
1330         /* look for last buffer to map */
1331         for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
1332                 if (NULL == q->bufs[last])
1333                         continue;
1334                 if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
1335                         continue;
1336                 if (q->bufs[last]->map) {
1337                         retval = -EBUSY;
1338                         goto done;
1339                 }
1340                 size += q->bufs[last]->bsize;
1341                 if (size == (vma->vm_end - vma->vm_start))
1342                         break;
1343         }
1344         if (VIDEO_MAX_FRAME == last) {
1345                 dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n",
1346                         (vma->vm_end - vma->vm_start));
1347                 goto done;
1348         }
1349
1350         /* create mapping + update buffer list */
1351         retval = -ENOMEM;
1352         map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
1353         if (NULL == map)
1354                 goto done;
1355         for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) {
1356                 q->bufs[i]->map   = map;
1357                 q->bufs[i]->baddr = vma->vm_start + size;
1358         }
1359         map->count    = 1;
1360         map->start    = vma->vm_start;
1361         map->end      = vma->vm_end;
1362         map->q        = q;
1363         vma->vm_ops   = &videobuf_vm_ops;
1364         vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
1365         vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
1366         vma->vm_private_data = map;
1367         dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
1368                 map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
1369         retval = 0;
1370
1371  done:
1372         mutex_unlock(&q->lock);
1373         return retval;
1374 }
1375
1376 /* --------------------------------------------------------------------- */
1377
1378 EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
1379
1380 EXPORT_SYMBOL_GPL(videobuf_dma_init);
1381 EXPORT_SYMBOL_GPL(videobuf_dma_init_user);
1382 EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel);
1383 EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay);
1384 EXPORT_SYMBOL_GPL(videobuf_dma_map);
1385 EXPORT_SYMBOL_GPL(videobuf_dma_sync);
1386 EXPORT_SYMBOL_GPL(videobuf_dma_unmap);
1387 EXPORT_SYMBOL_GPL(videobuf_dma_free);
1388
1389 EXPORT_SYMBOL_GPL(videobuf_pci_dma_map);
1390 EXPORT_SYMBOL_GPL(videobuf_pci_dma_unmap);
1391
1392 EXPORT_SYMBOL_GPL(videobuf_alloc);
1393 EXPORT_SYMBOL_GPL(videobuf_waiton);
1394 EXPORT_SYMBOL_GPL(videobuf_iolock);
1395
1396 EXPORT_SYMBOL_GPL(videobuf_queue_init);
1397 EXPORT_SYMBOL_GPL(videobuf_queue_cancel);
1398 EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
1399
1400 EXPORT_SYMBOL_GPL(videobuf_next_field);
1401 EXPORT_SYMBOL_GPL(videobuf_status);
1402 EXPORT_SYMBOL_GPL(videobuf_reqbufs);
1403 EXPORT_SYMBOL_GPL(videobuf_querybuf);
1404 EXPORT_SYMBOL_GPL(videobuf_qbuf);
1405 EXPORT_SYMBOL_GPL(videobuf_dqbuf);
1406 EXPORT_SYMBOL_GPL(videobuf_streamon);
1407 EXPORT_SYMBOL_GPL(videobuf_streamoff);
1408
1409 EXPORT_SYMBOL_GPL(videobuf_read_start);
1410 EXPORT_SYMBOL_GPL(videobuf_read_stop);
1411 EXPORT_SYMBOL_GPL(videobuf_read_stream);
1412 EXPORT_SYMBOL_GPL(videobuf_read_one);
1413 EXPORT_SYMBOL_GPL(videobuf_poll_stream);
1414
1415 EXPORT_SYMBOL_GPL(videobuf_mmap_setup);
1416 EXPORT_SYMBOL_GPL(videobuf_mmap_free);
1417 EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);
1418
1419 /*
1420  * Local variables:
1421  * c-basic-offset: 8
1422  * End:
1423  */