SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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/vmalloc.h>
  28 #include <linux/pagemap.h>
  29 #include <linux/slab.h>
  30 #include <linux/pci.h>
  31 #include <linux/interrupt.h>
  32 #include <asm/page.h>
  33 #include <asm/pgtable.h>
  34
  35 #include <media/video-buf.h>
  36
  37 #define MAGIC_DMABUF 0x19721112
  38 #define MAGIC_BUFFER 0x20040302
  39 #define MAGIC_CHECK(is,should)  if (unlikely((is) != (should))) \
  40         { printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); }
  41
  42 static int debug = 0;
  43 module_param(debug, int, 0644);
  44
  45 MODULE_DESCRIPTION("helper module to manage video4linux pci dma buffers");
  46 MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
  47 MODULE_LICENSE("GPL");
  48
  49 #define dprintk(level, fmt, arg...)     if (debug >= level) \
  50         printk(KERN_DEBUG "vbuf: " fmt , ## arg)
  51
  52 struct scatterlist*
  53 videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages)
  54 {
  55         struct scatterlist *sglist;
  56         struct page *pg;
  57         int i;
  58
  59         sglist = kcalloc(nr_pages, sizeof(struct scatterlist), GFP_KERNEL);
  60         if (NULL == sglist)
  61                 return NULL;
  62         for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
  63                 pg = vmalloc_to_page(virt);
  64                 if (NULL == pg)
  65                         goto err;
  66                 BUG_ON(PageHighMem(pg));
  67                 sglist[i].page   = pg;
  68                 sglist[i].length = PAGE_SIZE;
  69         }
  70         return sglist;
  71
  72  err:
  73         kfree(sglist);
  74         return NULL;
  75 }
  76
  77 struct scatterlist*
  78 videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset)
  79 {
  80         struct scatterlist *sglist;
  81         int i = 0;
  82
  83         if (NULL == pages[0])
  84                 return NULL;
  85         sglist = kcalloc(nr_pages, sizeof(*sglist), GFP_KERNEL);
  86         if (NULL == sglist)
  87                 return NULL;
  88
  89         if (NULL == pages[0])
  90                 goto nopage;
  91         if (PageHighMem(pages[0]))
  92                 /* DMA to highmem pages might not work */
  93                 goto highmem;
  94         sglist[0].page   = pages[0];
  95         sglist[0].offset = offset;
  96         sglist[0].length = PAGE_SIZE - offset;
  97         for (i = 1; i < nr_pages; i++) {
  98                 if (NULL == pages[i])
  99                         goto nopage;
 100                 if (PageHighMem(pages[i]))
 101                         goto highmem;
 102                 sglist[i].page   = pages[i];
 103                 sglist[i].length = PAGE_SIZE;
 104         }
 105         return sglist;
 106
 107  nopage:
 108         dprintk(2,"sgl: oops - no page\n");
 109         kfree(sglist);
 110         return NULL;
 111
 112  highmem:
 113         dprintk(2,"sgl: oops - highmem page\n");
 114         kfree(sglist);
 115         return NULL;
 116 }
 117
 118 /* --------------------------------------------------------------------- */
 119
 120 void videobuf_dma_init(struct videobuf_dmabuf *dma)
 121 {
 122         memset(dma,0,sizeof(*dma));
 123         dma->magic = MAGIC_DMABUF;
 124 }
 125
 126 int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
 127                            unsigned long data, unsigned long size)
 128 {
 129         unsigned long first,last;
 130         int err, rw = 0;
 131
 132         dma->direction = direction;
 133         switch (dma->direction) {
 134         case PCI_DMA_FROMDEVICE: rw = READ;  break;
 135         case PCI_DMA_TODEVICE:   rw = WRITE; break;
 136         default:                 BUG();
 137         }
 138
 139         first = (data          & PAGE_MASK) >> PAGE_SHIFT;
 140         last  = ((data+size-1) & PAGE_MASK) >> PAGE_SHIFT;
 141         dma->offset   = data & ~PAGE_MASK;
 142         dma->nr_pages = last-first+1;
 143         dma->pages = kmalloc(dma->nr_pages * sizeof(struct page*),
 144                              GFP_KERNEL);
 145         if (NULL == dma->pages)
 146                 return -ENOMEM;
 147         dprintk(1,"init user [0x%lx+0x%lx => %d pages]\n",
 148                 data,size,dma->nr_pages);
 149
 150         dma->varea = (void *) data;
 151
 152         down_read(&current->mm->mmap_sem);
 153         err = get_user_pages(current,current->mm,
 154                              data & PAGE_MASK, dma->nr_pages,
 155                              rw == READ, 1, /* force */
 156                              dma->pages, NULL);
 157         up_read(&current->mm->mmap_sem);
 158         if (err != dma->nr_pages) {
 159                 dma->nr_pages = (err >= 0) ? err : 0;
 160                 dprintk(1,"get_user_pages: err=%d [%d]\n",err,dma->nr_pages);
 161                 return err < 0 ? err : -EINVAL;
 162         }
 163         return 0;
 164 }
 165
 166 int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
 167                              int nr_pages)
 168 {
 169         dprintk(1,"init kernel [%d pages]\n",nr_pages);
 170         dma->direction = direction;
 171         dma->vmalloc = vmalloc_32(nr_pages << PAGE_SHIFT);
 172         if (NULL == dma->vmalloc) {
 173                 dprintk(1,"vmalloc_32(%d pages) failed\n",nr_pages);
 174                 return -ENOMEM;
 175         }
 176         dprintk(1,"vmalloc is at addr 0x%08lx, size=%d\n",
 177                                 (unsigned long)dma->vmalloc,
 178                                 nr_pages << PAGE_SHIFT);
 179         memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT);
 180         dma->nr_pages = nr_pages;
 181         return 0;
 182 }
 183
 184 int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
 185                               dma_addr_t addr, int nr_pages)
 186 {
 187         dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n",
 188                 nr_pages,(unsigned long)addr);
 189         dma->direction = direction;
 190         if (0 == addr)
 191                 return -EINVAL;
 192
 193         dma->bus_addr = addr;
 194         dma->nr_pages = nr_pages;
 195         return 0;
 196 }
 197
 198 int videobuf_dma_map(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
 199 {
 200         void                   *dev=q->dev;
 201
 202         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 203         BUG_ON(0 == dma->nr_pages);
 204
 205         if (dma->pages) {
 206                 dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
 207                                                    dma->offset);
 208         }
 209         if (dma->vmalloc) {
 210                 dma->sglist = videobuf_vmalloc_to_sg
 211                                                 (dma->vmalloc,dma->nr_pages);
 212         }
 213         if (dma->bus_addr) {
 214                 dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
 215                 if (NULL != dma->sglist) {
 216                         dma->sglen  = 1;
 217                         sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK;
 218                         dma->sglist[0].offset           = dma->bus_addr & ~PAGE_MASK;
 219                         sg_dma_len(&dma->sglist[0])     = dma->nr_pages * PAGE_SIZE;
 220                 }
 221         }
 222         if (NULL == dma->sglist) {
 223                 dprintk(1,"scatterlist is NULL\n");
 224                 return -ENOMEM;
 225         }
 226         if (!dma->bus_addr) {
 227                 if (q->ops->vb_map_sg) {
 228                         dma->sglen = q->ops->vb_map_sg(dev,dma->sglist,
 229                                         dma->nr_pages, dma->direction);
 230                 }
 231                 if (0 == dma->sglen) {
 232                         printk(KERN_WARNING
 233                                "%s: videobuf_map_sg failed\n",__FUNCTION__);
 234                         kfree(dma->sglist);
 235                         dma->sglist = NULL;
 236                         dma->sglen = 0;
 237                         return -EIO;
 238                 }
 239         }
 240         return 0;
 241 }
 242
 243 int videobuf_dma_sync(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
 244 {
 245         void                   *dev=q->dev;
 246
 247         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 248         BUG_ON(!dma->sglen);
 249
 250         if (!dma->bus_addr && q->ops->vb_dma_sync_sg)
 251                 q->ops->vb_dma_sync_sg(dev,dma->sglist,dma->nr_pages,
 252                                                         dma->direction);
 253
 254         return 0;
 255 }
 256
 257 int videobuf_dma_unmap(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
 258 {
 259         void                   *dev=q->dev;
 260
 261         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 262         if (!dma->sglen)
 263                 return 0;
 264
 265         if (!dma->bus_addr && q->ops->vb_unmap_sg)
 266                         q->ops->vb_unmap_sg(dev,dma->sglist,dma->nr_pages,
 267                                                         dma->direction);
 268         kfree(dma->sglist);
 269         dma->sglist = NULL;
 270         dma->sglen = 0;
 271         return 0;
 272 }
 273
 274 int videobuf_dma_free(struct videobuf_dmabuf *dma)
 275 {
 276         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 277         BUG_ON(dma->sglen);
 278
 279         if (dma->pages) {
 280                 int i;
 281                 for (i=0; i < dma->nr_pages; i++)
 282                         page_cache_release(dma->pages[i]);
 283                 kfree(dma->pages);
 284                 dma->pages = NULL;
 285         }
 286
 287         vfree(dma->vmalloc);
 288         dma->vmalloc = NULL;
 289         dma->varea = NULL;
 290
 291         if (dma->bus_addr) {
 292                 dma->bus_addr = 0;
 293         }
 294         dma->direction = PCI_DMA_NONE;
 295         return 0;
 296 }
 297
 298 /* --------------------------------------------------------------------- */
 299
 300 void* videobuf_alloc(unsigned int size)
 301 {
 302         struct videobuf_buffer *vb;
 303
 304         vb = kzalloc(size,GFP_KERNEL);
 305         if (NULL != vb) {
 306                 videobuf_dma_init(&vb->dma);
 307                 init_waitqueue_head(&vb->done);
 308                 vb->magic     = MAGIC_BUFFER;
 309         }
 310         return vb;
 311 }
 312
 313 int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
 314 {
 315         int retval = 0;
 316         DECLARE_WAITQUEUE(wait, current);
 317
 318         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 319         add_wait_queue(&vb->done, &wait);
 320         while (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED) {
 321                 if (non_blocking) {
 322                         retval = -EAGAIN;
 323                         break;
 324                 }
 325                 set_current_state(intr  ? TASK_INTERRUPTIBLE
 326                                         : TASK_UNINTERRUPTIBLE);
 327                 if (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED)
 328                         schedule();
 329                 set_current_state(TASK_RUNNING);
 330                 if (intr && signal_pending(current)) {
 331                         dprintk(1,"buffer waiton: -EINTR\n");
 332                         retval = -EINTR;
 333                         break;
 334                 }
 335         }
 336         remove_wait_queue(&vb->done, &wait);
 337         return retval;
 338 }
 339
 340 int
 341 videobuf_iolock(struct videobuf_queue* q, struct videobuf_buffer *vb,
 342                 struct v4l2_framebuffer *fbuf)
 343 {
 344         int err,pages;
 345         dma_addr_t bus;
 346
 347         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 348         switch (vb->memory) {
 349         case V4L2_MEMORY_MMAP:
 350         case V4L2_MEMORY_USERPTR:
 351                 if (0 == vb->baddr) {
 352                         /* no userspace addr -- kernel bounce buffer */
 353                         pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
 354                         err = videobuf_dma_init_kernel(&vb->dma,PCI_DMA_FROMDEVICE,
 355                                                        pages);
 356                         if (0 != err)
 357                                 return err;
 358                 } else {
 359                         /* dma directly to userspace */
 360                         err = videobuf_dma_init_user(&vb->dma,PCI_DMA_FROMDEVICE,
 361                                                      vb->baddr,vb->bsize);
 362                         if (0 != err)
 363                                 return err;
 364                 }
 365                 break;
 366         case V4L2_MEMORY_OVERLAY:
 367                 if (NULL == fbuf)
 368                         return -EINVAL;
 369                 /* FIXME: need sanity checks for vb->boff */
 370                 /*
 371                  * Using a double cast to avoid compiler warnings when
 372                  * building for PAE. Compiler doesn't like direct casting
 373                  * of a 32 bit ptr to 64 bit integer.
 374                  */
 375                 bus   = (dma_addr_t)(unsigned long)fbuf->base + vb->boff;
 376                 pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
 377                 err = videobuf_dma_init_overlay(&vb->dma,PCI_DMA_FROMDEVICE,
 378                                                 bus, pages);
 379                 if (0 != err)
 380                         return err;
 381                 break;
 382         default:
 383                 BUG();
 384         }
 385         err = videobuf_dma_map(q,&vb->dma);
 386         if (0 != err)
 387                 return err;
 388
 389         return 0;
 390 }
 391
 392 /* --------------------------------------------------------------------- */
 393
 394 void videobuf_queue_pci(struct videobuf_queue* q)
 395 {
 396         /* If not specified, defaults to PCI map sg */
 397         if (!q->ops->vb_map_sg)
 398                 q->ops->vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 399
 400         if (!q->ops->vb_dma_sync_sg)
 401                 q->ops->vb_dma_sync_sg=(vb_map_sg_t *)pci_dma_sync_sg_for_cpu;
 402         if (!q->ops->vb_unmap_sg)
 403                 q->ops->vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 404 }
 405
 406 int videobuf_pci_dma_map(struct pci_dev *pci,struct videobuf_dmabuf *dma)
 407 {
 408         struct videobuf_queue q;
 409         struct videobuf_queue_ops qops;
 410
 411         q.dev=pci;
 412         qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 413         qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 414         q.ops = &qops;
 415
 416         return (videobuf_dma_map(&q,dma));
 417 }
 418
 419 int videobuf_pci_dma_unmap(struct pci_dev *pci,struct videobuf_dmabuf *dma)
 420 {
 421         struct videobuf_queue q;
 422         struct videobuf_queue_ops qops;
 423
 424         q.dev=pci;
 425         qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 426         qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 427         q.ops = &qops;
 428
 429         return (videobuf_dma_unmap(&q,dma));
 430 }
 431
 432 void videobuf_queue_init(struct videobuf_queue* q,
 433                          struct videobuf_queue_ops *ops,
 434                          void *dev,
 435                          spinlock_t *irqlock,
 436                          enum v4l2_buf_type type,
 437                          enum v4l2_field field,
 438                          unsigned int msize,
 439                          void *priv)
 440 {
 441         memset(q,0,sizeof(*q));
 442         q->irqlock = irqlock;
 443         q->dev     = dev;
 444         q->type    = type;
 445         q->field   = field;
 446         q->msize   = msize;
 447         q->ops     = ops;
 448         q->priv_data = priv;
 449
 450         videobuf_queue_pci(q);
 451
 452         mutex_init(&q->lock);
 453         INIT_LIST_HEAD(&q->stream);
 454 }
 455
 456 int
 457 videobuf_queue_is_busy(struct videobuf_queue *q)
 458 {
 459         int i;
 460
 461         if (q->streaming) {
 462                 dprintk(1,"busy: streaming active\n");
 463                 return 1;
 464         }
 465         if (q->reading) {
 466                 dprintk(1,"busy: pending read #1\n");
 467                 return 1;
 468         }
 469         if (q->read_buf) {
 470                 dprintk(1,"busy: pending read #2\n");
 471                 return 1;
 472         }
 473         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 474                 if (NULL == q->bufs[i])
 475                         continue;
 476                 if (q->bufs[i]->map) {
 477                         dprintk(1,"busy: buffer #%d mapped\n",i);
 478                         return 1;
 479                 }
 480                 if (q->bufs[i]->state == STATE_QUEUED) {
 481                         dprintk(1,"busy: buffer #%d queued\n",i);
 482                         return 1;
 483                 }
 484                 if (q->bufs[i]->state == STATE_ACTIVE) {
 485                         dprintk(1,"busy: buffer #%d avtive\n",i);
 486                         return 1;
 487                 }
 488         }
 489         return 0;
 490 }
 491
 492 void
 493 videobuf_queue_cancel(struct videobuf_queue *q)
 494 {
 495         unsigned long flags=0;
 496         int i;
 497
 498         /* remove queued buffers from list */
 499         if (q->irqlock)
 500                 spin_lock_irqsave(q->irqlock,flags);
 501         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 502                 if (NULL == q->bufs[i])
 503                         continue;
 504                 if (q->bufs[i]->state == STATE_QUEUED) {
 505                         list_del(&q->bufs[i]->queue);
 506                         q->bufs[i]->state = STATE_ERROR;
 507                 }
 508         }
 509         if (q->irqlock)
 510                 spin_unlock_irqrestore(q->irqlock,flags);
 511
 512         /* free all buffers + clear queue */
 513         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 514                 if (NULL == q->bufs[i])
 515                         continue;
 516                 q->ops->buf_release(q,q->bufs[i]);
 517         }
 518         INIT_LIST_HEAD(&q->stream);
 519 }
 520
 521 /* --------------------------------------------------------------------- */
 522
 523 enum v4l2_field
 524 videobuf_next_field(struct videobuf_queue *q)
 525 {
 526         enum v4l2_field field = q->field;
 527
 528         BUG_ON(V4L2_FIELD_ANY == field);
 529
 530         if (V4L2_FIELD_ALTERNATE == field) {
 531                 if (V4L2_FIELD_TOP == q->last) {
 532                         field   = V4L2_FIELD_BOTTOM;
 533                         q->last = V4L2_FIELD_BOTTOM;
 534                 } else {
 535                         field   = V4L2_FIELD_TOP;
 536                         q->last = V4L2_FIELD_TOP;
 537                 }
 538         }
 539         return field;
 540 }
 541
 542 void
 543 videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb,
 544                 enum v4l2_buf_type type)
 545 {
 546         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 547
 548         b->index    = vb->i;
 549         b->type     = type;
 550
 551         b->memory   = vb->memory;
 552         switch (b->memory) {
 553         case V4L2_MEMORY_MMAP:
 554                 b->m.offset  = vb->boff;
 555                 b->length    = vb->bsize;
 556                 break;
 557         case V4L2_MEMORY_USERPTR:
 558                 b->m.userptr = vb->baddr;
 559                 b->length    = vb->bsize;
 560                 break;
 561         case V4L2_MEMORY_OVERLAY:
 562                 b->m.offset  = vb->boff;
 563                 break;
 564         }
 565
 566         b->flags    = 0;
 567         if (vb->map)
 568                 b->flags |= V4L2_BUF_FLAG_MAPPED;
 569
 570         switch (vb->state) {
 571         case STATE_PREPARED:
 572         case STATE_QUEUED:
 573         case STATE_ACTIVE:
 574                 b->flags |= V4L2_BUF_FLAG_QUEUED;
 575                 break;
 576         case STATE_DONE:
 577         case STATE_ERROR:
 578                 b->flags |= V4L2_BUF_FLAG_DONE;
 579                 break;
 580         case STATE_NEEDS_INIT:
 581         case STATE_IDLE:
 582                 /* nothing */
 583                 break;
 584         }
 585
 586         if (vb->input != UNSET) {
 587                 b->flags |= V4L2_BUF_FLAG_INPUT;
 588                 b->input  = vb->input;
 589         }
 590
 591         b->field     = vb->field;
 592         b->timestamp = vb->ts;
 593         b->bytesused = vb->size;
 594         b->sequence  = vb->field_count >> 1;
 595 }
 596
 597 int
 598 videobuf_reqbufs(struct videobuf_queue *q,
 599                  struct v4l2_requestbuffers *req)
 600 {
 601         unsigned int size,count;
 602         int retval;
 603
 604         if (req->type != q->type) {
 605                 dprintk(1,"reqbufs: queue type invalid\n");
 606                 return -EINVAL;
 607         }
 608         if (req->count < 1) {
 609                 dprintk(1,"reqbufs: count invalid (%d)\n",req->count);
 610                 return -EINVAL;
 611         }
 612         if (req->memory != V4L2_MEMORY_MMAP     &&
 613             req->memory != V4L2_MEMORY_USERPTR  &&
 614             req->memory != V4L2_MEMORY_OVERLAY) {
 615                 dprintk(1,"reqbufs: memory type invalid\n");
 616                 return -EINVAL;
 617         }
 618
 619         if (q->streaming) {
 620                 dprintk(1,"reqbufs: streaming already exists\n");
 621                 return -EBUSY;
 622         }
 623         if (!list_empty(&q->stream)) {
 624                 dprintk(1,"reqbufs: stream running\n");
 625                 return -EBUSY;
 626         }
 627
 628         mutex_lock(&q->lock);
 629         count = req->count;
 630         if (count > VIDEO_MAX_FRAME)
 631                 count = VIDEO_MAX_FRAME;
 632         size = 0;
 633         q->ops->buf_setup(q,&count,&size);
 634         size = PAGE_ALIGN(size);
 635         dprintk(1,"reqbufs: bufs=%d, size=0x%x [%d pages total]\n",
 636                 count, size, (count*size)>>PAGE_SHIFT);
 637
 638         retval = videobuf_mmap_setup(q,count,size,req->memory);
 639         if (retval < 0) {
 640                 dprintk(1,"reqbufs: mmap setup returned %d\n",retval);
 641                 goto done;
 642         }
 643
 644         req->count = count;
 645
 646  done:
 647         mutex_unlock(&q->lock);
 648         return retval;
 649 }
 650
 651 int
 652 videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b)
 653 {
 654         if (unlikely(b->type != q->type)) {
 655                 dprintk(1,"querybuf: Wrong type.\n");
 656                 return -EINVAL;
 657         }
 658         if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME)) {
 659                 dprintk(1,"querybuf: index out of range.\n");
 660                 return -EINVAL;
 661         }
 662         if (unlikely(NULL == q->bufs[b->index])) {
 663                 dprintk(1,"querybuf: buffer is null.\n");
 664                 return -EINVAL;
 665         }
 666         videobuf_status(b,q->bufs[b->index],q->type);
 667         return 0;
 668 }
 669
 670 int
 671 videobuf_qbuf(struct videobuf_queue *q,
 672               struct v4l2_buffer *b)
 673 {
 674         struct videobuf_buffer *buf;
 675         enum v4l2_field field;
 676         unsigned long flags=0;
 677         int retval;
 678
 679         mutex_lock(&q->lock);
 680         retval = -EBUSY;
 681         if (q->reading) {
 682                 dprintk(1,"qbuf: Reading running...\n");
 683                 goto done;
 684         }
 685         retval = -EINVAL;
 686         if (b->type != q->type) {
 687                 dprintk(1,"qbuf: Wrong type.\n");
 688                 goto done;
 689         }
 690         if (b->index < 0 || b->index >= VIDEO_MAX_FRAME) {
 691                 dprintk(1,"qbuf: index out of range.\n");
 692                 goto done;
 693         }
 694         buf = q->bufs[b->index];
 695         if (NULL == buf) {
 696                 dprintk(1,"qbuf: buffer is null.\n");
 697                 goto done;
 698         }
 699         MAGIC_CHECK(buf->magic,MAGIC_BUFFER);
 700         if (buf->memory != b->memory) {
 701                 dprintk(1,"qbuf: memory type is wrong.\n");
 702                 goto done;
 703         }
 704         if (buf->state != STATE_NEEDS_INIT && buf->state != STATE_IDLE) {
 705                 dprintk(1,"qbuf: buffer is already queued or active.\n");
 706                 goto done;
 707         }
 708
 709         if (b->flags & V4L2_BUF_FLAG_INPUT) {
 710                 if (b->input >= q->inputs) {
 711                         dprintk(1,"qbuf: wrong input.\n");
 712                         goto done;
 713                 }
 714                 buf->input = b->input;
 715         } else {
 716                 buf->input = UNSET;
 717         }
 718
 719         switch (b->memory) {
 720         case V4L2_MEMORY_MMAP:
 721                 if (0 == buf->baddr) {
 722                         dprintk(1,"qbuf: mmap requested but buffer addr is zero!\n");
 723                         goto done;
 724                 }
 725                 break;
 726         case V4L2_MEMORY_USERPTR:
 727                 if (b->length < buf->bsize) {
 728                         dprintk(1,"qbuf: buffer length is not enough\n");
 729                         goto done;
 730                 }
 731                 if (STATE_NEEDS_INIT != buf->state && buf->baddr != b->m.userptr)
 732                         q->ops->buf_release(q,buf);
 733                 buf->baddr = b->m.userptr;
 734                 break;
 735         case V4L2_MEMORY_OVERLAY:
 736                 buf->boff = b->m.offset;
 737                 break;
 738         default:
 739                 dprintk(1,"qbuf: wrong memory type\n");
 740                 goto done;
 741         }
 742
 743         dprintk(1,"qbuf: requesting next field\n");
 744         field = videobuf_next_field(q);
 745         retval = q->ops->buf_prepare(q,buf,field);
 746         if (0 != retval) {
 747                 dprintk(1,"qbuf: buffer_prepare returned %d\n",retval);
 748                 goto done;
 749         }
 750
 751         list_add_tail(&buf->stream,&q->stream);
 752         if (q->streaming) {
 753                 if (q->irqlock)
 754                         spin_lock_irqsave(q->irqlock,flags);
 755                 q->ops->buf_queue(q,buf);
 756                 if (q->irqlock)
 757                         spin_unlock_irqrestore(q->irqlock,flags);
 758         }
 759         dprintk(1,"qbuf: succeded\n");
 760         retval = 0;
 761
 762  done:
 763         mutex_unlock(&q->lock);
 764         return retval;
 765 }
 766
 767 int
 768 videobuf_dqbuf(struct videobuf_queue *q,
 769                struct v4l2_buffer *b, int nonblocking)
 770 {
 771         struct videobuf_buffer *buf;
 772         int retval;
 773
 774         mutex_lock(&q->lock);
 775         retval = -EBUSY;
 776         if (q->reading) {
 777                 dprintk(1,"dqbuf: Reading running...\n");
 778                 goto done;
 779         }
 780         retval = -EINVAL;
 781         if (b->type != q->type) {
 782                 dprintk(1,"dqbuf: Wrong type.\n");
 783                 goto done;
 784         }
 785         if (list_empty(&q->stream)) {
 786                 dprintk(1,"dqbuf: stream running\n");
 787                 goto done;
 788         }
 789         buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
 790         retval = videobuf_waiton(buf, nonblocking, 1);
 791         if (retval < 0) {
 792                 dprintk(1,"dqbuf: waiton returned %d\n",retval);
 793                 goto done;
 794         }
 795         switch (buf->state) {
 796         case STATE_ERROR:
 797                 dprintk(1,"dqbuf: state is error\n");
 798                 retval = -EIO;
 799                 videobuf_dma_sync(q,&buf->dma);
 800                 buf->state = STATE_IDLE;
 801                 break;
 802         case STATE_DONE:
 803                 dprintk(1,"dqbuf: state is done\n");
 804                 videobuf_dma_sync(q,&buf->dma);
 805                 buf->state = STATE_IDLE;
 806                 break;
 807         default:
 808                 dprintk(1,"dqbuf: state invalid\n");
 809                 retval = -EINVAL;
 810                 goto done;
 811         }
 812         list_del(&buf->stream);
 813         memset(b,0,sizeof(*b));
 814         videobuf_status(b,buf,q->type);
 815
 816  done:
 817         mutex_unlock(&q->lock);
 818         return retval;
 819 }
 820
 821 int videobuf_streamon(struct videobuf_queue *q)
 822 {
 823         struct videobuf_buffer *buf;
 824         struct list_head *list;
 825         unsigned long flags=0;
 826         int retval;
 827
 828         mutex_lock(&q->lock);
 829         retval = -EBUSY;
 830         if (q->reading)
 831                 goto done;
 832         retval = 0;
 833         if (q->streaming)
 834                 goto done;
 835         q->streaming = 1;
 836         if (q->irqlock)
 837                 spin_lock_irqsave(q->irqlock,flags);
 838         list_for_each(list,&q->stream) {
 839                 buf = list_entry(list, struct videobuf_buffer, stream);
 840                 if (buf->state == STATE_PREPARED)
 841                         q->ops->buf_queue(q,buf);
 842         }
 843         if (q->irqlock)
 844                 spin_unlock_irqrestore(q->irqlock,flags);
 845
 846  done:
 847         mutex_unlock(&q->lock);
 848         return retval;
 849 }
 850
 851 int videobuf_streamoff(struct videobuf_queue *q)
 852 {
 853         int retval = -EINVAL;
 854
 855         mutex_lock(&q->lock);
 856         if (!q->streaming)
 857                 goto done;
 858         videobuf_queue_cancel(q);
 859         q->streaming = 0;
 860         retval = 0;
 861
 862  done:
 863         mutex_unlock(&q->lock);
 864         return retval;
 865 }
 866
 867 static ssize_t
 868 videobuf_read_zerocopy(struct videobuf_queue *q, char __user *data,
 869                        size_t count, loff_t *ppos)
 870 {
 871         enum v4l2_field field;
 872         unsigned long flags=0;
 873         int retval;
 874
 875         /* setup stuff */
 876         q->read_buf = videobuf_alloc(q->msize);
 877         if (NULL == q->read_buf)
 878                 return -ENOMEM;
 879
 880         q->read_buf->memory = V4L2_MEMORY_USERPTR;
 881         q->read_buf->baddr  = (unsigned long)data;
 882         q->read_buf->bsize  = count;
 883         field = videobuf_next_field(q);
 884         retval = q->ops->buf_prepare(q,q->read_buf,field);
 885         if (0 != retval)
 886                 goto done;
 887
 888         /* start capture & wait */
 889         if (q->irqlock)
 890                 spin_lock_irqsave(q->irqlock,flags);
 891         q->ops->buf_queue(q,q->read_buf);
 892         if (q->irqlock)
 893                 spin_unlock_irqrestore(q->irqlock,flags);
 894         retval = videobuf_waiton(q->read_buf,0,0);
 895         if (0 == retval) {
 896                 videobuf_dma_sync(q,&q->read_buf->dma);
 897                 if (STATE_ERROR == q->read_buf->state)
 898                         retval = -EIO;
 899                 else
 900                         retval = q->read_buf->size;
 901         }
 902
 903  done:
 904         /* cleanup */
 905         q->ops->buf_release(q,q->read_buf);
 906         kfree(q->read_buf);
 907         q->read_buf = NULL;
 908         return retval;
 909 }
 910
 911 ssize_t videobuf_read_one(struct videobuf_queue *q,
 912                           char __user *data, size_t count, loff_t *ppos,
 913                           int nonblocking)
 914 {
 915         enum v4l2_field field;
 916         unsigned long flags=0;
 917         unsigned size, nbufs, bytes;
 918         int retval;
 919
 920         mutex_lock(&q->lock);
 921
 922         nbufs = 1; size = 0;
 923         q->ops->buf_setup(q,&nbufs,&size);
 924         if (NULL == q->read_buf  &&
 925             count >= size        &&
 926             !nonblocking) {
 927                 retval = videobuf_read_zerocopy(q,data,count,ppos);
 928                 if (retval >= 0  ||  retval == -EIO)
 929                         /* ok, all done */
 930                         goto done;
 931                 /* fallback to kernel bounce buffer on failures */
 932         }
 933
 934         if (NULL == q->read_buf) {
 935                 /* need to capture a new frame */
 936                 retval = -ENOMEM;
 937                 q->read_buf = videobuf_alloc(q->msize);
 938                 dprintk(1,"video alloc=0x%p\n", q->read_buf);
 939                 if (NULL == q->read_buf)
 940                         goto done;
 941                 q->read_buf->memory = V4L2_MEMORY_USERPTR;
 942                 q->read_buf->bsize = count; /* preferred size */
 943                 field = videobuf_next_field(q);
 944                 retval = q->ops->buf_prepare(q,q->read_buf,field);
 945                 if (0 != retval) {
 946                         kfree (q->read_buf);
 947                         q->read_buf = NULL;
 948                         goto done;
 949                 }
 950                 if (q->irqlock)
 951                         spin_lock_irqsave(q->irqlock,flags);
 952                 q->ops->buf_queue(q,q->read_buf);
 953                 if (q->irqlock)
 954                         spin_unlock_irqrestore(q->irqlock,flags);
 955                 q->read_off = 0;
 956         }
 957
 958         /* wait until capture is done */
 959         retval = videobuf_waiton(q->read_buf, nonblocking, 1);
 960         if (0 != retval)
 961                 goto done;
 962         videobuf_dma_sync(q,&q->read_buf->dma);
 963
 964         if (STATE_ERROR == q->read_buf->state) {
 965                 /* catch I/O errors */
 966                 q->ops->buf_release(q,q->read_buf);
 967                 kfree(q->read_buf);
 968                 q->read_buf = NULL;
 969                 retval = -EIO;
 970                 goto done;
 971         }
 972
 973         /* copy to userspace */
 974         bytes = count;
 975         if (bytes > q->read_buf->size - q->read_off)
 976                 bytes = q->read_buf->size - q->read_off;
 977         retval = -EFAULT;
 978         if (copy_to_user(data, q->read_buf->dma.vmalloc+q->read_off, bytes))
 979                 goto done;
 980
 981         retval = bytes;
 982         q->read_off += bytes;
 983         if (q->read_off == q->read_buf->size) {
 984                 /* all data copied, cleanup */
 985                 q->ops->buf_release(q,q->read_buf);
 986                 kfree(q->read_buf);
 987                 q->read_buf = NULL;
 988         }
 989
 990  done:
 991         mutex_unlock(&q->lock);
 992         return retval;
 993 }
 994
 995 int videobuf_read_start(struct videobuf_queue *q)
 996 {
 997         enum v4l2_field field;
 998         unsigned long flags=0;
 999         int count = 0, size = 0;
1000         int err, i;
1001
1002         q->ops->buf_setup(q,&count,&size);
1003         if (count < 2)
1004                 count = 2;
1005         if (count > VIDEO_MAX_FRAME)
1006                 count = VIDEO_MAX_FRAME;
1007         size = PAGE_ALIGN(size);
1008
1009         err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
1010         if (err)
1011                 return err;
1012         for (i = 0; i < count; i++) {
1013                 field = videobuf_next_field(q);
1014                 err = q->ops->buf_prepare(q,q->bufs[i],field);
1015                 if (err)
1016                         return err;
1017                 list_add_tail(&q->bufs[i]->stream, &q->stream);
1018         }
1019         if (q->irqlock)
1020                 spin_lock_irqsave(q->irqlock,flags);
1021         for (i = 0; i < count; i++)
1022                 q->ops->buf_queue(q,q->bufs[i]);
1023         if (q->irqlock)
1024                 spin_unlock_irqrestore(q->irqlock,flags);
1025         q->reading = 1;
1026         return 0;
1027 }
1028
1029 void videobuf_read_stop(struct videobuf_queue *q)
1030 {
1031         int i;
1032
1033         videobuf_queue_cancel(q);
1034         videobuf_mmap_free(q);
1035         INIT_LIST_HEAD(&q->stream);
1036         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1037                 if (NULL == q->bufs[i])
1038                         continue;
1039                 kfree(q->bufs[i]);
1040                 q->bufs[i] = NULL;
1041         }
1042         q->read_buf = NULL;
1043         q->reading  = 0;
1044 }
1045
1046 ssize_t videobuf_read_stream(struct videobuf_queue *q,
1047                              char __user *data, size_t count, loff_t *ppos,
1048                              int vbihack, int nonblocking)
1049 {
1050         unsigned int *fc, bytes;
1051         int err, retval;
1052         unsigned long flags=0;
1053
1054         dprintk(2,"%s\n",__FUNCTION__);
1055         mutex_lock(&q->lock);
1056         retval = -EBUSY;
1057         if (q->streaming)
1058                 goto done;
1059         if (!q->reading) {
1060                 retval = videobuf_read_start(q);
1061                 if (retval < 0)
1062                         goto done;
1063         }
1064
1065         retval = 0;
1066         while (count > 0) {
1067                 /* get / wait for data */
1068                 if (NULL == q->read_buf) {
1069                         q->read_buf = list_entry(q->stream.next,
1070                                                  struct videobuf_buffer,
1071                                                  stream);
1072                         list_del(&q->read_buf->stream);
1073                         q->read_off = 0;
1074                 }
1075                 err = videobuf_waiton(q->read_buf, nonblocking, 1);
1076                 if (err < 0) {
1077                         if (0 == retval)
1078                                 retval = err;
1079                         break;
1080                 }
1081
1082                 if (q->read_buf->state == STATE_DONE) {
1083                         if (vbihack) {
1084                                 /* dirty, undocumented hack -- pass the frame counter
1085                                  * within the last four bytes of each vbi data block.
1086                                  * We need that one to maintain backward compatibility
1087                                  * to all vbi decoding software out there ... */
1088                                 fc  = (unsigned int*)q->read_buf->dma.vmalloc;
1089                                 fc += (q->read_buf->size>>2) -1;
1090                                 *fc = q->read_buf->field_count >> 1;
1091                                 dprintk(1,"vbihack: %d\n",*fc);
1092                         }
1093
1094                         /* copy stuff */
1095                         bytes = count;
1096                         if (bytes > q->read_buf->size - q->read_off)
1097                                 bytes = q->read_buf->size - q->read_off;
1098                         if (copy_to_user(data + retval,
1099                                          q->read_buf->dma.vmalloc + q->read_off,
1100                                          bytes)) {
1101                                 if (0 == retval)
1102                                         retval = -EFAULT;
1103                                 break;
1104                         }
1105                         count       -= bytes;
1106                         retval      += bytes;
1107                         q->read_off += bytes;
1108                 } else {
1109                         /* some error */
1110                         q->read_off = q->read_buf->size;
1111                         if (0 == retval)
1112                                 retval = -EIO;
1113                 }
1114
1115                 /* requeue buffer when done with copying */
1116                 if (q->read_off == q->read_buf->size) {
1117                         list_add_tail(&q->read_buf->stream,
1118                                       &q->stream);
1119                         if (q->irqlock)
1120                                 spin_lock_irqsave(q->irqlock,flags);
1121                         q->ops->buf_queue(q,q->read_buf);
1122                         if (q->irqlock)
1123                                 spin_unlock_irqrestore(q->irqlock,flags);
1124                         q->read_buf = NULL;
1125                 }
1126                 if (retval < 0)
1127                         break;
1128         }
1129
1130  done:
1131         mutex_unlock(&q->lock);
1132         return retval;
1133 }
1134
1135 unsigned int videobuf_poll_stream(struct file *file,
1136                                   struct videobuf_queue *q,
1137                                   poll_table *wait)
1138 {
1139         struct videobuf_buffer *buf = NULL;
1140         unsigned int rc = 0;
1141
1142         mutex_lock(&q->lock);
1143         if (q->streaming) {
1144                 if (!list_empty(&q->stream))
1145                         buf = list_entry(q->stream.next,
1146                                          struct videobuf_buffer, stream);
1147         } else {
1148                 if (!q->reading)
1149                         videobuf_read_start(q);
1150                 if (!q->reading) {
1151                         rc = POLLERR;
1152                 } else if (NULL == q->read_buf) {
1153                         q->read_buf = list_entry(q->stream.next,
1154                                                  struct videobuf_buffer,
1155                                                  stream);
1156                         list_del(&q->read_buf->stream);
1157                         q->read_off = 0;
1158                 }
1159                 buf = q->read_buf;
1160         }
1161         if (!buf)
1162                 rc = POLLERR;
1163
1164         if (0 == rc) {
1165                 poll_wait(file, &buf->done, wait);
1166                 if (buf->state == STATE_DONE ||
1167                     buf->state == STATE_ERROR)
1168                         rc = POLLIN|POLLRDNORM;
1169         }
1170         mutex_unlock(&q->lock);
1171         return rc;
1172 }
1173
1174 /* --------------------------------------------------------------------- */
1175
1176 static void
1177 videobuf_vm_open(struct vm_area_struct *vma)
1178 {
1179         struct videobuf_mapping *map = vma->vm_private_data;
1180
1181         dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
1182                 map->count,vma->vm_start,vma->vm_end);
1183         map->count++;
1184 }
1185
1186 static void
1187 videobuf_vm_close(struct vm_area_struct *vma)
1188 {
1189         struct videobuf_mapping *map = vma->vm_private_data;
1190         struct videobuf_queue *q = map->q;
1191         int i;
1192
1193         dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
1194                 map->count,vma->vm_start,vma->vm_end);
1195
1196         map->count--;
1197         if (0 == map->count) {
1198                 dprintk(1,"munmap %p q=%p\n",map,q);
1199                 mutex_lock(&q->lock);
1200                 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1201                         if (NULL == q->bufs[i])
1202                                 continue;
1203                         if (q->bufs[i])
1204                                 ;
1205                         if (q->bufs[i]->map != map)
1206                                 continue;
1207                         q->bufs[i]->map   = NULL;
1208                         q->bufs[i]->baddr = 0;
1209                         q->ops->buf_release(q,q->bufs[i]);
1210                 }
1211                 mutex_unlock(&q->lock);
1212                 kfree(map);
1213         }
1214         return;
1215 }
1216
1217 /*
1218  * Get a anonymous page for the mapping.  Make sure we can DMA to that
1219  * memory location with 32bit PCI devices (i.e. don't use highmem for
1220  * now ...).  Bounce buffers don't work very well for the data rates
1221  * video capture has.
1222  */
1223 static struct page*
1224 videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
1225                    int *type)
1226 {
1227         struct page *page;
1228
1229         dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n",
1230                 vaddr,vma->vm_start,vma->vm_end);
1231         if (vaddr > vma->vm_end)
1232                 return NOPAGE_SIGBUS;
1233         page = alloc_page(GFP_USER | __GFP_DMA32);
1234         if (!page)
1235                 return NOPAGE_OOM;
1236         clear_user_page(page_address(page), vaddr, page);
1237         if (type)
1238                 *type = VM_FAULT_MINOR;
1239         return page;
1240 }
1241
1242 static struct vm_operations_struct videobuf_vm_ops =
1243 {
1244         .open     = videobuf_vm_open,
1245         .close    = videobuf_vm_close,
1246         .nopage   = videobuf_vm_nopage,
1247 };
1248
1249 int videobuf_mmap_setup(struct videobuf_queue *q,
1250                         unsigned int bcount, unsigned int bsize,
1251                         enum v4l2_memory memory)
1252 {
1253         unsigned int i;
1254         int err;
1255
1256         err = videobuf_mmap_free(q);
1257         if (0 != err)
1258                 return err;
1259
1260         for (i = 0; i < bcount; i++) {
1261                 q->bufs[i] = videobuf_alloc(q->msize);
1262                 q->bufs[i]->i      = i;
1263                 q->bufs[i]->input  = UNSET;
1264                 q->bufs[i]->memory = memory;
1265                 q->bufs[i]->bsize  = bsize;
1266                 switch (memory) {
1267                 case V4L2_MEMORY_MMAP:
1268                         q->bufs[i]->boff  = bsize * i;
1269                         break;
1270                 case V4L2_MEMORY_USERPTR:
1271                 case V4L2_MEMORY_OVERLAY:
1272                         /* nothing */
1273                         break;
1274                 }
1275         }
1276         dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
1277                 bcount,bsize);
1278         return 0;
1279 }
1280
1281 int videobuf_mmap_free(struct videobuf_queue *q)
1282 {
1283         int i;
1284
1285         for (i = 0; i < VIDEO_MAX_FRAME; i++)
1286                 if (q->bufs[i] && q->bufs[i]->map)
1287                         return -EBUSY;
1288         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1289                 if (NULL == q->bufs[i])
1290                         continue;
1291                 q->ops->buf_release(q,q->bufs[i]);
1292                 kfree(q->bufs[i]);
1293                 q->bufs[i] = NULL;
1294         }
1295         return 0;
1296 }
1297
1298 int videobuf_mmap_mapper(struct videobuf_queue *q,
1299                          struct vm_area_struct *vma)
1300 {
1301         struct videobuf_mapping *map;
1302         unsigned int first,last,size,i;
1303         int retval;
1304
1305         mutex_lock(&q->lock);
1306         retval = -EINVAL;
1307         if (!(vma->vm_flags & VM_WRITE)) {
1308                 dprintk(1,"mmap app bug: PROT_WRITE please\n");
1309                 goto done;
1310         }
1311         if (!(vma->vm_flags & VM_SHARED)) {
1312                 dprintk(1,"mmap app bug: MAP_SHARED please\n");
1313                 goto done;
1314         }
1315
1316         /* look for first buffer to map */
1317         for (first = 0; first < VIDEO_MAX_FRAME; first++) {
1318                 if (NULL == q->bufs[first])
1319                         continue;
1320                 if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
1321                         continue;
1322                 if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
1323                         break;
1324         }
1325         if (VIDEO_MAX_FRAME == first) {
1326                 dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
1327                         (vma->vm_pgoff << PAGE_SHIFT));
1328                 goto done;
1329         }
1330
1331         /* look for last buffer to map */
1332         for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
1333                 if (NULL == q->bufs[last])
1334                         continue;
1335                 if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
1336                         continue;
1337                 if (q->bufs[last]->map) {
1338                         retval = -EBUSY;
1339                         goto done;
1340                 }
1341                 size += q->bufs[last]->bsize;
1342                 if (size == (vma->vm_end - vma->vm_start))
1343                         break;
1344         }
1345         if (VIDEO_MAX_FRAME == last) {
1346                 dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n",
1347                         (vma->vm_end - vma->vm_start));
1348                 goto done;
1349         }
1350
1351         /* create mapping + update buffer list */
1352         retval = -ENOMEM;
1353         map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
1354         if (NULL == map)
1355                 goto done;
1356         for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) {
1357                 q->bufs[i]->map   = map;
1358                 q->bufs[i]->baddr = vma->vm_start + size;
1359         }
1360         map->count    = 1;
1361         map->start    = vma->vm_start;
1362         map->end      = vma->vm_end;
1363         map->q        = q;
1364         vma->vm_ops   = &videobuf_vm_ops;
1365         vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
1366         vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
1367         vma->vm_private_data = map;
1368         dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
1369                 map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
1370         retval = 0;
1371
1372  done:
1373         mutex_unlock(&q->lock);
1374         return retval;
1375 }
1376
1377 /* --------------------------------------------------------------------- */
1378
1379 EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
1380
1381 EXPORT_SYMBOL_GPL(videobuf_dma_init);
1382 EXPORT_SYMBOL_GPL(videobuf_dma_init_user);
1383 EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel);
1384 EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay);
1385 EXPORT_SYMBOL_GPL(videobuf_dma_map);
1386 EXPORT_SYMBOL_GPL(videobuf_dma_sync);
1387 EXPORT_SYMBOL_GPL(videobuf_dma_unmap);
1388 EXPORT_SYMBOL_GPL(videobuf_dma_free);
1389
1390 EXPORT_SYMBOL_GPL(videobuf_pci_dma_map);
1391 EXPORT_SYMBOL_GPL(videobuf_pci_dma_unmap);
1392
1393 EXPORT_SYMBOL_GPL(videobuf_alloc);
1394 EXPORT_SYMBOL_GPL(videobuf_waiton);
1395 EXPORT_SYMBOL_GPL(videobuf_iolock);
1396
1397 EXPORT_SYMBOL_GPL(videobuf_queue_init);
1398 EXPORT_SYMBOL_GPL(videobuf_queue_cancel);
1399 EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
1400
1401 EXPORT_SYMBOL_GPL(videobuf_next_field);
1402 EXPORT_SYMBOL_GPL(videobuf_status);
1403 EXPORT_SYMBOL_GPL(videobuf_reqbufs);
1404 EXPORT_SYMBOL_GPL(videobuf_querybuf);
1405 EXPORT_SYMBOL_GPL(videobuf_qbuf);
1406 EXPORT_SYMBOL_GPL(videobuf_dqbuf);
1407 EXPORT_SYMBOL_GPL(videobuf_streamon);
1408 EXPORT_SYMBOL_GPL(videobuf_streamoff);
1409
1410 EXPORT_SYMBOL_GPL(videobuf_read_start);
1411 EXPORT_SYMBOL_GPL(videobuf_read_stop);
1412 EXPORT_SYMBOL_GPL(videobuf_read_stream);
1413 EXPORT_SYMBOL_GPL(videobuf_read_one);
1414 EXPORT_SYMBOL_GPL(videobuf_poll_stream);
1415
1416 EXPORT_SYMBOL_GPL(videobuf_mmap_setup);
1417 EXPORT_SYMBOL_GPL(videobuf_mmap_free);
1418 EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);
1419
1420 /*
1421  * Local variables:
1422  * c-basic-offset: 8
1423  * End:
1424  */