git.oblomov.eu Git - 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/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         dma->varea = (void *) data;
 152
 153         down_read(&current->mm->mmap_sem);
 154         err = get_user_pages(current,current->mm,
 155                              data & PAGE_MASK, dma->nr_pages,
 156                              rw == READ, 1, /* force */
 157                              dma->pages, NULL);
 158         up_read(&current->mm->mmap_sem);
 159         if (err != dma->nr_pages) {
 160                 dma->nr_pages = (err >= 0) ? err : 0;
 161                 dprintk(1,"get_user_pages: err=%d [%d]\n",err,dma->nr_pages);
 162                 return err < 0 ? err : -EINVAL;
 163         }
 164         return 0;
 165 }
 166
 167 int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
 168                              int nr_pages)
 169 {
 170         dprintk(1,"init kernel [%d pages]\n",nr_pages);
 171         dma->direction = direction;
 172         dma->vmalloc = vmalloc_32(nr_pages << PAGE_SHIFT);
 173         if (NULL == dma->vmalloc) {
 174                 dprintk(1,"vmalloc_32(%d pages) failed\n",nr_pages);
 175                 return -ENOMEM;
 176         }
 177         dprintk(1,"vmalloc is at addr 0x%08lx, size=%d\n",
 178                                 (unsigned long)dma->vmalloc,
 179                                 nr_pages << PAGE_SHIFT);
 180         memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT);
 181         dma->nr_pages = nr_pages;
 182         return 0;
 183 }
 184
 185 int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
 186                               dma_addr_t addr, int nr_pages)
 187 {
 188         dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n",
 189                 nr_pages,(unsigned long)addr);
 190         dma->direction = direction;
 191         if (0 == addr)
 192                 return -EINVAL;
 193
 194         dma->bus_addr = addr;
 195         dma->nr_pages = nr_pages;
 196         return 0;
 197 }
 198
 199 int videobuf_dma_map(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
 200 {
 201         void                   *dev=q->dev;
 202
 203         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 204         BUG_ON(0 == dma->nr_pages);
 205
 206         if (dma->pages) {
 207                 dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
 208                                                    dma->offset);
 209         }
 210         if (dma->vmalloc) {
 211                 dma->sglist = videobuf_vmalloc_to_sg
 212                                                 (dma->vmalloc,dma->nr_pages);
 213         }
 214         if (dma->bus_addr) {
 215                 dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
 216                 if (NULL != dma->sglist) {
 217                         dma->sglen  = 1;
 218                         sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK;
 219                         dma->sglist[0].offset           = dma->bus_addr & ~PAGE_MASK;
 220                         sg_dma_len(&dma->sglist[0])     = dma->nr_pages * PAGE_SIZE;
 221                 }
 222         }
 223         if (NULL == dma->sglist) {
 224                 dprintk(1,"scatterlist is NULL\n");
 225                 return -ENOMEM;
 226         }
 227         if (!dma->bus_addr) {
 228                 if (q->ops->vb_map_sg) {
 229                         dma->sglen = q->ops->vb_map_sg(dev,dma->sglist,
 230                                         dma->nr_pages, dma->direction);
 231                 }
 232                 if (0 == dma->sglen) {
 233                         printk(KERN_WARNING
 234                                "%s: videobuf_map_sg failed\n",__FUNCTION__);
 235                         kfree(dma->sglist);
 236                         dma->sglist = NULL;
 237                         dma->sglen = 0;
 238                         return -EIO;
 239                 }
 240         }
 241         return 0;
 242 }
 243
 244 int videobuf_dma_sync(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
 245 {
 246         void                   *dev=q->dev;
 247
 248         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 249         BUG_ON(!dma->sglen);
 250
 251         if (!dma->bus_addr && q->ops->vb_dma_sync_sg)
 252                 q->ops->vb_dma_sync_sg(dev,dma->sglist,dma->nr_pages,
 253                                                         dma->direction);
 254
 255         return 0;
 256 }
 257
 258 int videobuf_dma_unmap(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
 259 {
 260         void                   *dev=q->dev;
 261
 262         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 263         if (!dma->sglen)
 264                 return 0;
 265
 266         if (!dma->bus_addr && q->ops->vb_unmap_sg)
 267                         q->ops->vb_unmap_sg(dev,dma->sglist,dma->nr_pages,
 268                                                         dma->direction);
 269         kfree(dma->sglist);
 270         dma->sglist = NULL;
 271         dma->sglen = 0;
 272         return 0;
 273 }
 274
 275 int videobuf_dma_free(struct videobuf_dmabuf *dma)
 276 {
 277         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 278         BUG_ON(dma->sglen);
 279
 280         if (dma->pages) {
 281                 int i;
 282                 for (i=0; i < dma->nr_pages; i++)
 283                         page_cache_release(dma->pages[i]);
 284                 kfree(dma->pages);
 285                 dma->pages = NULL;
 286         }
 287
 288         vfree(dma->vmalloc);
 289         dma->vmalloc = NULL;
 290         dma->varea = NULL;
 291
 292         if (dma->bus_addr) {
 293                 dma->bus_addr = 0;
 294         }
 295         dma->direction = PCI_DMA_NONE;
 296         return 0;
 297 }
 298
 299 /* --------------------------------------------------------------------- */
 300
 301 void* videobuf_alloc(unsigned int size)
 302 {
 303         struct videobuf_buffer *vb;
 304
 305         vb = kzalloc(size,GFP_KERNEL);
 306         if (NULL != vb) {
 307                 videobuf_dma_init(&vb->dma);
 308                 init_waitqueue_head(&vb->done);
 309                 vb->magic     = MAGIC_BUFFER;
 310         }
 311         return vb;
 312 }
 313
 314 int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
 315 {
 316         int retval = 0;
 317         DECLARE_WAITQUEUE(wait, current);
 318
 319         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 320         add_wait_queue(&vb->done, &wait);
 321         while (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED) {
 322                 if (non_blocking) {
 323                         retval = -EAGAIN;
 324                         break;
 325                 }
 326                 set_current_state(intr  ? TASK_INTERRUPTIBLE
 327                                         : TASK_UNINTERRUPTIBLE);
 328                 if (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED)
 329                         schedule();
 330                 set_current_state(TASK_RUNNING);
 331                 if (intr && signal_pending(current)) {
 332                         dprintk(1,"buffer waiton: -EINTR\n");
 333                         retval = -EINTR;
 334                         break;
 335                 }
 336         }
 337         remove_wait_queue(&vb->done, &wait);
 338         return retval;
 339 }
 340
 341 int
 342 videobuf_iolock(struct videobuf_queue* q, struct videobuf_buffer *vb,
 343                 struct v4l2_framebuffer *fbuf)
 344 {
 345         int err,pages;
 346         dma_addr_t bus;
 347
 348         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 349         switch (vb->memory) {
 350         case V4L2_MEMORY_MMAP:
 351         case V4L2_MEMORY_USERPTR:
 352                 if (0 == vb->baddr) {
 353                         /* no userspace addr -- kernel bounce buffer */
 354                         pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
 355                         err = videobuf_dma_init_kernel(&vb->dma,PCI_DMA_FROMDEVICE,
 356                                                        pages);
 357                         if (0 != err)
 358                                 return err;
 359                 } else {
 360                         /* dma directly to userspace */
 361                         err = videobuf_dma_init_user(&vb->dma,PCI_DMA_FROMDEVICE,
 362                                                      vb->baddr,vb->bsize);
 363                         if (0 != err)
 364                                 return err;
 365                 }
 366                 break;
 367         case V4L2_MEMORY_OVERLAY:
 368                 if (NULL == fbuf)
 369                         return -EINVAL;
 370                 /* FIXME: need sanity checks for vb->boff */
 371                 /*
 372                  * Using a double cast to avoid compiler warnings when
 373                  * building for PAE. Compiler doesn't like direct casting
 374                  * of a 32 bit ptr to 64 bit integer.
 375                  */
 376                 bus   = (dma_addr_t)(unsigned long)fbuf->base + vb->boff;
 377                 pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
 378                 err = videobuf_dma_init_overlay(&vb->dma,PCI_DMA_FROMDEVICE,
 379                                                 bus, pages);
 380                 if (0 != err)
 381                         return err;
 382                 break;
 383         default:
 384                 BUG();
 385         }
 386         err = videobuf_dma_map(q,&vb->dma);
 387         if (0 != err)
 388                 return err;
 389
 390         return 0;
 391 }
 392
 393 /* --------------------------------------------------------------------- */
 394
 395 void videobuf_queue_pci(struct videobuf_queue* q)
 396 {
 397         /* If not specified, defaults to PCI map sg */
 398         if (!q->ops->vb_map_sg)
 399                 q->ops->vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 400
 401         if (!q->ops->vb_dma_sync_sg)
 402                 q->ops->vb_dma_sync_sg=(vb_map_sg_t *)pci_dma_sync_sg_for_cpu;
 403         if (!q->ops->vb_unmap_sg)
 404                 q->ops->vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 405 }
 406
 407 int videobuf_pci_dma_map(struct pci_dev *pci,struct videobuf_dmabuf *dma)
 408 {
 409         struct videobuf_queue q;
 410         struct videobuf_queue_ops qops;
 411
 412         q.dev=pci;
 413         qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 414         qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 415         q.ops = &qops;
 416
 417         return (videobuf_dma_map(&q,dma));
 418 }
 419
 420 int videobuf_pci_dma_unmap(struct pci_dev *pci,struct videobuf_dmabuf *dma)
 421 {
 422         struct videobuf_queue q;
 423         struct videobuf_queue_ops qops;
 424
 425         q.dev=pci;
 426         qops.vb_map_sg=(vb_map_sg_t *)pci_map_sg;
 427         qops.vb_unmap_sg=(vb_map_sg_t *)pci_unmap_sg;
 428         q.ops = &qops;
 429
 430         return (videobuf_dma_unmap(&q,dma));
 431 }
 432
 433 void videobuf_queue_init(struct videobuf_queue* q,
 434                          struct videobuf_queue_ops *ops,
 435                          void *dev,
 436                          spinlock_t *irqlock,
 437                          enum v4l2_buf_type type,
 438                          enum v4l2_field field,
 439                          unsigned int msize,
 440                          void *priv)
 441 {
 442         memset(q,0,sizeof(*q));
 443         q->irqlock = irqlock;
 444         q->dev     = dev;
 445         q->type    = type;
 446         q->field   = field;
 447         q->msize   = msize;
 448         q->ops     = ops;
 449         q->priv_data = priv;
 450
 451         videobuf_queue_pci(q);
 452
 453         mutex_init(&q->lock);
 454         INIT_LIST_HEAD(&q->stream);
 455 }
 456
 457 int
 458 videobuf_queue_is_busy(struct videobuf_queue *q)
 459 {
 460         int i;
 461
 462         if (q->streaming) {
 463                 dprintk(1,"busy: streaming active\n");
 464                 return 1;
 465         }
 466         if (q->reading) {
 467                 dprintk(1,"busy: pending read #1\n");
 468                 return 1;
 469         }
 470         if (q->read_buf) {
 471                 dprintk(1,"busy: pending read #2\n");
 472                 return 1;
 473         }
 474         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 475                 if (NULL == q->bufs[i])
 476                         continue;
 477                 if (q->bufs[i]->map) {
 478                         dprintk(1,"busy: buffer #%d mapped\n",i);
 479                         return 1;
 480                 }
 481                 if (q->bufs[i]->state == STATE_QUEUED) {
 482                         dprintk(1,"busy: buffer #%d queued\n",i);
 483                         return 1;
 484                 }
 485                 if (q->bufs[i]->state == STATE_ACTIVE) {
 486                         dprintk(1,"busy: buffer #%d avtive\n",i);
 487                         return 1;
 488                 }
 489         }
 490         return 0;
 491 }
 492
 493 void
 494 videobuf_queue_cancel(struct videobuf_queue *q)
 495 {
 496         unsigned long flags=0;
 497         int i;
 498
 499         /* remove queued buffers from list */
 500         if (q->irqlock)
 501                 spin_lock_irqsave(q->irqlock,flags);
 502         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 503                 if (NULL == q->bufs[i])
 504                         continue;
 505                 if (q->bufs[i]->state == STATE_QUEUED) {
 506                         list_del(&q->bufs[i]->queue);
 507                         q->bufs[i]->state = STATE_ERROR;
 508                 }
 509         }
 510         if (q->irqlock)
 511                 spin_unlock_irqrestore(q->irqlock,flags);
 512
 513         /* free all buffers + clear queue */
 514         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 515                 if (NULL == q->bufs[i])
 516                         continue;
 517                 q->ops->buf_release(q,q->bufs[i]);
 518         }
 519         INIT_LIST_HEAD(&q->stream);
 520 }
 521
 522 /* --------------------------------------------------------------------- */
 523
 524 enum v4l2_field
 525 videobuf_next_field(struct videobuf_queue *q)
 526 {
 527         enum v4l2_field field = q->field;
 528
 529         BUG_ON(V4L2_FIELD_ANY == field);
 530
 531         if (V4L2_FIELD_ALTERNATE == field) {
 532                 if (V4L2_FIELD_TOP == q->last) {
 533                         field   = V4L2_FIELD_BOTTOM;
 534                         q->last = V4L2_FIELD_BOTTOM;
 535                 } else {
 536                         field   = V4L2_FIELD_TOP;
 537                         q->last = V4L2_FIELD_TOP;
 538                 }
 539         }
 540         return field;
 541 }
 542
 543 void
 544 videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb,
 545                 enum v4l2_buf_type type)
 546 {
 547         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 548
 549         b->index    = vb->i;
 550         b->type     = type;
 551
 552         b->memory   = vb->memory;
 553         switch (b->memory) {
 554         case V4L2_MEMORY_MMAP:
 555                 b->m.offset  = vb->boff;
 556                 b->length    = vb->bsize;
 557                 break;
 558         case V4L2_MEMORY_USERPTR:
 559                 b->m.userptr = vb->baddr;
 560                 b->length    = vb->bsize;
 561                 break;
 562         case V4L2_MEMORY_OVERLAY:
 563                 b->m.offset  = vb->boff;
 564                 break;
 565         }
 566
 567         b->flags    = 0;
 568         if (vb->map)
 569                 b->flags |= V4L2_BUF_FLAG_MAPPED;
 570
 571         switch (vb->state) {
 572         case STATE_PREPARED:
 573         case STATE_QUEUED:
 574         case STATE_ACTIVE:
 575                 b->flags |= V4L2_BUF_FLAG_QUEUED;
 576                 break;
 577         case STATE_DONE:
 578         case STATE_ERROR:
 579                 b->flags |= V4L2_BUF_FLAG_DONE;
 580                 break;
 581         case STATE_NEEDS_INIT:
 582         case STATE_IDLE:
 583                 /* nothing */
 584                 break;
 585         }
 586
 587         if (vb->input != UNSET) {
 588                 b->flags |= V4L2_BUF_FLAG_INPUT;
 589                 b->input  = vb->input;
 590         }
 591
 592         b->field     = vb->field;
 593         b->timestamp = vb->ts;
 594         b->bytesused = vb->size;
 595         b->sequence  = vb->field_count >> 1;
 596 }
 597
 598 int
 599 videobuf_reqbufs(struct videobuf_queue *q,
 600                  struct v4l2_requestbuffers *req)
 601 {
 602         unsigned int size,count;
 603         int retval;
 604
 605         if (req->type != q->type) {
 606                 dprintk(1,"reqbufs: queue type invalid\n");
 607                 return -EINVAL;
 608         }
 609         if (req->count < 1) {
 610                 dprintk(1,"reqbufs: count invalid (%d)\n",req->count);
 611                 return -EINVAL;
 612         }
 613         if (req->memory != V4L2_MEMORY_MMAP     &&
 614             req->memory != V4L2_MEMORY_USERPTR  &&
 615             req->memory != V4L2_MEMORY_OVERLAY) {
 616                 dprintk(1,"reqbufs: memory type invalid\n");
 617                 return -EINVAL;
 618         }
 619
 620         if (q->streaming) {
 621                 dprintk(1,"reqbufs: streaming already exists\n");
 622                 return -EBUSY;
 623         }
 624         if (!list_empty(&q->stream)) {
 625                 dprintk(1,"reqbufs: stream running\n");
 626                 return -EBUSY;
 627         }
 628
 629         mutex_lock(&q->lock);
 630         count = req->count;
 631         if (count > VIDEO_MAX_FRAME)
 632                 count = VIDEO_MAX_FRAME;
 633         size = 0;
 634         q->ops->buf_setup(q,&count,&size);
 635         size = PAGE_ALIGN(size);
 636         dprintk(1,"reqbufs: bufs=%d, size=0x%x [%d pages total]\n",
 637                 count, size, (count*size)>>PAGE_SHIFT);
 638
 639         retval = videobuf_mmap_setup(q,count,size,req->memory);
 640         if (retval < 0) {
 641                 dprintk(1,"reqbufs: mmap setup returned %d\n",retval);
 642                 goto done;
 643         }
 644
 645         req->count = count;
 646
 647  done:
 648         mutex_unlock(&q->lock);
 649         return retval;
 650 }
 651
 652 int
 653 videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b)
 654 {
 655         if (unlikely(b->type != q->type)) {
 656                 dprintk(1,"querybuf: Wrong type.\n");
 657                 return -EINVAL;
 658         }
 659         if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME)) {
 660                 dprintk(1,"querybuf: index out of range.\n");
 661                 return -EINVAL;
 662         }
 663         if (unlikely(NULL == q->bufs[b->index])) {
 664                 dprintk(1,"querybuf: buffer is null.\n");
 665                 return -EINVAL;
 666         }
 667         videobuf_status(b,q->bufs[b->index],q->type);
 668         return 0;
 669 }
 670
 671 int
 672 videobuf_qbuf(struct videobuf_queue *q,
 673               struct v4l2_buffer *b)
 674 {
 675         struct videobuf_buffer *buf;
 676         enum v4l2_field field;
 677         unsigned long flags=0;
 678         int retval;
 679
 680         mutex_lock(&q->lock);
 681         retval = -EBUSY;
 682         if (q->reading) {
 683                 dprintk(1,"qbuf: Reading running...\n");
 684                 goto done;
 685         }
 686         retval = -EINVAL;
 687         if (b->type != q->type) {
 688                 dprintk(1,"qbuf: Wrong type.\n");
 689                 goto done;
 690         }
 691         if (b->index < 0 || b->index >= VIDEO_MAX_FRAME) {
 692                 dprintk(1,"qbuf: index out of range.\n");
 693                 goto done;
 694         }
 695         buf = q->bufs[b->index];
 696         if (NULL == buf) {
 697                 dprintk(1,"qbuf: buffer is null.\n");
 698                 goto done;
 699         }
 700         MAGIC_CHECK(buf->magic,MAGIC_BUFFER);
 701         if (buf->memory != b->memory) {
 702                 dprintk(1,"qbuf: memory type is wrong.\n");
 703                 goto done;
 704         }
 705         if (buf->state != STATE_NEEDS_INIT && buf->state != STATE_IDLE) {
 706                 dprintk(1,"qbuf: buffer is already queued or active.\n");
 707                 goto done;
 708         }
 709
 710         if (b->flags & V4L2_BUF_FLAG_INPUT) {
 711                 if (b->input >= q->inputs) {
 712                         dprintk(1,"qbuf: wrong input.\n");
 713                         goto done;
 714                 }
 715                 buf->input = b->input;
 716         } else {
 717                 buf->input = UNSET;
 718         }
 719
 720         switch (b->memory) {
 721         case V4L2_MEMORY_MMAP:
 722                 if (0 == buf->baddr) {
 723                         dprintk(1,"qbuf: mmap requested but buffer addr is zero!\n");
 724                         goto done;
 725                 }
 726                 break;
 727         case V4L2_MEMORY_USERPTR:
 728                 if (b->length < buf->bsize) {
 729                         dprintk(1,"qbuf: buffer length is not enough\n");
 730                         goto done;
 731                 }
 732                 if (STATE_NEEDS_INIT != buf->state && buf->baddr != b->m.userptr)
 733                         q->ops->buf_release(q,buf);
 734                 buf->baddr = b->m.userptr;
 735                 break;
 736         case V4L2_MEMORY_OVERLAY:
 737                 buf->boff = b->m.offset;
 738                 break;
 739         default:
 740                 dprintk(1,"qbuf: wrong memory type\n");
 741                 goto done;
 742         }
 743
 744         dprintk(1,"qbuf: requesting next field\n");
 745         field = videobuf_next_field(q);
 746         retval = q->ops->buf_prepare(q,buf,field);
 747         if (0 != retval) {
 748                 dprintk(1,"qbuf: buffer_prepare returned %d\n",retval);
 749                 goto done;
 750         }
 751
 752         list_add_tail(&buf->stream,&q->stream);
 753         if (q->streaming) {
 754                 if (q->irqlock)
 755                         spin_lock_irqsave(q->irqlock,flags);
 756                 q->ops->buf_queue(q,buf);
 757                 if (q->irqlock)
 758                         spin_unlock_irqrestore(q->irqlock,flags);
 759         }
 760         dprintk(1,"qbuf: succeded\n");
 761         retval = 0;
 762
 763  done:
 764         mutex_unlock(&q->lock);
 765         return retval;
 766 }
 767
 768 int
 769 videobuf_dqbuf(struct videobuf_queue *q,
 770                struct v4l2_buffer *b, int nonblocking)
 771 {
 772         struct videobuf_buffer *buf;
 773         int retval;
 774
 775         mutex_lock(&q->lock);
 776         retval = -EBUSY;
 777         if (q->reading) {
 778                 dprintk(1,"dqbuf: Reading running...\n");
 779                 goto done;
 780         }
 781         retval = -EINVAL;
 782         if (b->type != q->type) {
 783                 dprintk(1,"dqbuf: Wrong type.\n");
 784                 goto done;
 785         }
 786         if (list_empty(&q->stream)) {
 787                 dprintk(1,"dqbuf: stream running\n");
 788                 goto done;
 789         }
 790         buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
 791         retval = videobuf_waiton(buf, nonblocking, 1);
 792         if (retval < 0) {
 793                 dprintk(1,"dqbuf: waiton returned %d\n",retval);
 794                 goto done;
 795         }
 796         switch (buf->state) {
 797         case STATE_ERROR:
 798                 dprintk(1,"dqbuf: state is error\n");
 799                 retval = -EIO;
 800                 videobuf_dma_sync(q,&buf->dma);
 801                 buf->state = STATE_IDLE;
 802                 break;
 803         case STATE_DONE:
 804                 dprintk(1,"dqbuf: state is done\n");
 805                 videobuf_dma_sync(q,&buf->dma);
 806                 buf->state = STATE_IDLE;
 807                 break;
 808         default:
 809                 dprintk(1,"dqbuf: state invalid\n");
 810                 retval = -EINVAL;
 811                 goto done;
 812         }
 813         list_del(&buf->stream);
 814         memset(b,0,sizeof(*b));
 815         videobuf_status(b,buf,q->type);
 816
 817  done:
 818         mutex_unlock(&q->lock);
 819         return retval;
 820 }
 821
 822 int videobuf_streamon(struct videobuf_queue *q)
 823 {
 824         struct videobuf_buffer *buf;
 825         struct list_head *list;
 826         unsigned long flags=0;
 827         int retval;
 828
 829         mutex_lock(&q->lock);
 830         retval = -EBUSY;
 831         if (q->reading)
 832                 goto done;
 833         retval = 0;
 834         if (q->streaming)
 835                 goto done;
 836         q->streaming = 1;
 837         if (q->irqlock)
 838                 spin_lock_irqsave(q->irqlock,flags);
 839         list_for_each(list,&q->stream) {
 840                 buf = list_entry(list, struct videobuf_buffer, stream);
 841                 if (buf->state == STATE_PREPARED)
 842                         q->ops->buf_queue(q,buf);
 843         }
 844         if (q->irqlock)
 845                 spin_unlock_irqrestore(q->irqlock,flags);
 846
 847  done:
 848         mutex_unlock(&q->lock);
 849         return retval;
 850 }
 851
 852 int videobuf_streamoff(struct videobuf_queue *q)
 853 {
 854         int retval = -EINVAL;
 855
 856         mutex_lock(&q->lock);
 857         if (!q->streaming)
 858                 goto done;
 859         videobuf_queue_cancel(q);
 860         q->streaming = 0;
 861         retval = 0;
 862
 863  done:
 864         mutex_unlock(&q->lock);
 865         return retval;
 866 }
 867
 868 static ssize_t
 869 videobuf_read_zerocopy(struct videobuf_queue *q, char __user *data,
 870                        size_t count, loff_t *ppos)
 871 {
 872         enum v4l2_field field;
 873         unsigned long flags=0;
 874         int retval;
 875
 876         /* setup stuff */
 877         q->read_buf = videobuf_alloc(q->msize);
 878         if (NULL == q->read_buf)
 879                 return -ENOMEM;
 880
 881         q->read_buf->memory = V4L2_MEMORY_USERPTR;
 882         q->read_buf->baddr  = (unsigned long)data;
 883         q->read_buf->bsize  = count;
 884         field = videobuf_next_field(q);
 885         retval = q->ops->buf_prepare(q,q->read_buf,field);
 886         if (0 != retval)
 887                 goto done;
 888
 889         /* start capture & wait */
 890         if (q->irqlock)
 891                 spin_lock_irqsave(q->irqlock,flags);
 892         q->ops->buf_queue(q,q->read_buf);
 893         if (q->irqlock)
 894                 spin_unlock_irqrestore(q->irqlock,flags);
 895         retval = videobuf_waiton(q->read_buf,0,0);
 896         if (0 == retval) {
 897                 videobuf_dma_sync(q,&q->read_buf->dma);
 898                 if (STATE_ERROR == q->read_buf->state)
 899                         retval = -EIO;
 900                 else
 901                         retval = q->read_buf->size;
 902         }
 903
 904  done:
 905         /* cleanup */
 906         q->ops->buf_release(q,q->read_buf);
 907         kfree(q->read_buf);
 908         q->read_buf = NULL;
 909         return retval;
 910 }
 911
 912 ssize_t videobuf_read_one(struct videobuf_queue *q,
 913                           char __user *data, size_t count, loff_t *ppos,
 914                           int nonblocking)
 915 {
 916         enum v4l2_field field;
 917         unsigned long flags=0;
 918         unsigned size, nbufs, bytes;
 919         int retval;
 920
 921         mutex_lock(&q->lock);
 922
 923         nbufs = 1; size = 0;
 924         q->ops->buf_setup(q,&nbufs,&size);
 925         if (NULL == q->read_buf  &&
 926             count >= size        &&
 927             !nonblocking) {
 928                 retval = videobuf_read_zerocopy(q,data,count,ppos);
 929                 if (retval >= 0  ||  retval == -EIO)
 930                         /* ok, all done */
 931                         goto done;
 932                 /* fallback to kernel bounce buffer on failures */
 933         }
 934
 935         if (NULL == q->read_buf) {
 936                 /* need to capture a new frame */
 937                 retval = -ENOMEM;
 938                 q->read_buf = videobuf_alloc(q->msize);
 939                 dprintk(1,"video alloc=0x%p\n", q->read_buf);
 940                 if (NULL == q->read_buf)
 941                         goto done;
 942                 q->read_buf->memory = V4L2_MEMORY_USERPTR;
 943                 q->read_buf->bsize = count; /* preferred size */
 944                 field = videobuf_next_field(q);
 945                 retval = q->ops->buf_prepare(q,q->read_buf,field);
 946                 if (0 != retval) {
 947                         kfree (q->read_buf);
 948                         q->read_buf = NULL;
 949                         goto done;
 950                 }
 951                 if (q->irqlock)
 952                         spin_lock_irqsave(q->irqlock,flags);
 953                 q->ops->buf_queue(q,q->read_buf);
 954                 if (q->irqlock)
 955                         spin_unlock_irqrestore(q->irqlock,flags);
 956                 q->read_off = 0;
 957         }
 958
 959         /* wait until capture is done */
 960         retval = videobuf_waiton(q->read_buf, nonblocking, 1);
 961         if (0 != retval)
 962                 goto done;
 963         videobuf_dma_sync(q,&q->read_buf->dma);
 964
 965         if (STATE_ERROR == q->read_buf->state) {
 966                 /* catch I/O errors */
 967                 q->ops->buf_release(q,q->read_buf);
 968                 kfree(q->read_buf);
 969                 q->read_buf = NULL;
 970                 retval = -EIO;
 971                 goto done;
 972         }
 973
 974         /* copy to userspace */
 975         bytes = count;
 976         if (bytes > q->read_buf->size - q->read_off)
 977                 bytes = q->read_buf->size - q->read_off;
 978         retval = -EFAULT;
 979         if (copy_to_user(data, q->read_buf->dma.vmalloc+q->read_off, bytes))
 980                 goto done;
 981
 982         retval = bytes;
 983         q->read_off += bytes;
 984         if (q->read_off == q->read_buf->size) {
 985                 /* all data copied, cleanup */
 986                 q->ops->buf_release(q,q->read_buf);
 987                 kfree(q->read_buf);
 988                 q->read_buf = NULL;
 989         }
 990
 991  done:
 992         mutex_unlock(&q->lock);
 993         return retval;
 994 }
 995
 996 int videobuf_read_start(struct videobuf_queue *q)
 997 {
 998         enum v4l2_field field;
 999         unsigned long flags=0;
1000         int count = 0, size = 0;
1001         int err, i;
1002
1003         q->ops->buf_setup(q,&count,&size);
1004         if (count < 2)
1005                 count = 2;
1006         if (count > VIDEO_MAX_FRAME)
1007                 count = VIDEO_MAX_FRAME;
1008         size = PAGE_ALIGN(size);
1009
1010         err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
1011         if (err)
1012                 return err;
1013         for (i = 0; i < count; i++) {
1014                 field = videobuf_next_field(q);
1015                 err = q->ops->buf_prepare(q,q->bufs[i],field);
1016                 if (err)
1017                         return err;
1018                 list_add_tail(&q->bufs[i]->stream, &q->stream);
1019         }
1020         if (q->irqlock)
1021                 spin_lock_irqsave(q->irqlock,flags);
1022         for (i = 0; i < count; i++)
1023                 q->ops->buf_queue(q,q->bufs[i]);
1024         if (q->irqlock)
1025                 spin_unlock_irqrestore(q->irqlock,flags);
1026         q->reading = 1;
1027         return 0;
1028 }
1029
1030 void videobuf_read_stop(struct videobuf_queue *q)
1031 {
1032         int i;
1033
1034         videobuf_queue_cancel(q);
1035         videobuf_mmap_free(q);
1036         INIT_LIST_HEAD(&q->stream);
1037         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1038                 if (NULL == q->bufs[i])
1039                         continue;
1040                 kfree(q->bufs[i]);
1041                 q->bufs[i] = NULL;
1042         }
1043         q->read_buf = NULL;
1044         q->reading  = 0;
1045 }
1046
1047 ssize_t videobuf_read_stream(struct videobuf_queue *q,
1048                              char __user *data, size_t count, loff_t *ppos,
1049                              int vbihack, int nonblocking)
1050 {
1051         unsigned int *fc, bytes;
1052         int err, retval;
1053         unsigned long flags=0;
1054
1055         dprintk(2,"%s\n",__FUNCTION__);
1056         mutex_lock(&q->lock);
1057         retval = -EBUSY;
1058         if (q->streaming)
1059                 goto done;
1060         if (!q->reading) {
1061                 retval = videobuf_read_start(q);
1062                 if (retval < 0)
1063                         goto done;
1064         }
1065
1066         retval = 0;
1067         while (count > 0) {
1068                 /* get / wait for data */
1069                 if (NULL == q->read_buf) {
1070                         q->read_buf = list_entry(q->stream.next,
1071                                                  struct videobuf_buffer,
1072                                                  stream);
1073                         list_del(&q->read_buf->stream);
1074                         q->read_off = 0;
1075                 }
1076                 err = videobuf_waiton(q->read_buf, nonblocking, 1);
1077                 if (err < 0) {
1078                         if (0 == retval)
1079                                 retval = err;
1080                         break;
1081                 }
1082
1083                 if (q->read_buf->state == STATE_DONE) {
1084                         if (vbihack) {
1085                                 /* dirty, undocumented hack -- pass the frame counter
1086                                  * within the last four bytes of each vbi data block.
1087                                  * We need that one to maintain backward compatibility
1088                                  * to all vbi decoding software out there ... */
1089                                 fc  = (unsigned int*)q->read_buf->dma.vmalloc;
1090                                 fc += (q->read_buf->size>>2) -1;
1091                                 *fc = q->read_buf->field_count >> 1;
1092                                 dprintk(1,"vbihack: %d\n",*fc);
1093                         }
1094
1095                         /* copy stuff */
1096                         bytes = count;
1097                         if (bytes > q->read_buf->size - q->read_off)
1098                                 bytes = q->read_buf->size - q->read_off;
1099                         if (copy_to_user(data + retval,
1100                                          q->read_buf->dma.vmalloc + q->read_off,
1101                                          bytes)) {
1102                                 if (0 == retval)
1103                                         retval = -EFAULT;
1104                                 break;
1105                         }
1106                         count       -= bytes;
1107                         retval      += bytes;
1108                         q->read_off += bytes;
1109                 } else {
1110                         /* some error */
1111                         q->read_off = q->read_buf->size;
1112                         if (0 == retval)
1113                                 retval = -EIO;
1114                 }
1115
1116                 /* requeue buffer when done with copying */
1117                 if (q->read_off == q->read_buf->size) {
1118                         list_add_tail(&q->read_buf->stream,
1119                                       &q->stream);
1120                         if (q->irqlock)
1121                                 spin_lock_irqsave(q->irqlock,flags);
1122                         q->ops->buf_queue(q,q->read_buf);
1123                         if (q->irqlock)
1124                                 spin_unlock_irqrestore(q->irqlock,flags);
1125                         q->read_buf = NULL;
1126                 }
1127                 if (retval < 0)
1128                         break;
1129         }
1130
1131  done:
1132         mutex_unlock(&q->lock);
1133         return retval;
1134 }
1135
1136 unsigned int videobuf_poll_stream(struct file *file,
1137                                   struct videobuf_queue *q,
1138                                   poll_table *wait)
1139 {
1140         struct videobuf_buffer *buf = NULL;
1141         unsigned int rc = 0;
1142
1143         mutex_lock(&q->lock);
1144         if (q->streaming) {
1145                 if (!list_empty(&q->stream))
1146                         buf = list_entry(q->stream.next,
1147                                          struct videobuf_buffer, stream);
1148         } else {
1149                 if (!q->reading)
1150                         videobuf_read_start(q);
1151                 if (!q->reading) {
1152                         rc = POLLERR;
1153                 } else if (NULL == q->read_buf) {
1154                         q->read_buf = list_entry(q->stream.next,
1155                                                  struct videobuf_buffer,
1156                                                  stream);
1157                         list_del(&q->read_buf->stream);
1158                         q->read_off = 0;
1159                 }
1160                 buf = q->read_buf;
1161         }
1162         if (!buf)
1163                 rc = POLLERR;
1164
1165         if (0 == rc) {
1166                 poll_wait(file, &buf->done, wait);
1167                 if (buf->state == STATE_DONE ||
1168                     buf->state == STATE_ERROR)
1169                         rc = POLLIN|POLLRDNORM;
1170         }
1171         mutex_unlock(&q->lock);
1172         return rc;
1173 }
1174
1175 /* --------------------------------------------------------------------- */
1176
1177 static void
1178 videobuf_vm_open(struct vm_area_struct *vma)
1179 {
1180         struct videobuf_mapping *map = vma->vm_private_data;
1181
1182         dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
1183                 map->count,vma->vm_start,vma->vm_end);
1184         map->count++;
1185 }
1186
1187 static void
1188 videobuf_vm_close(struct vm_area_struct *vma)
1189 {
1190         struct videobuf_mapping *map = vma->vm_private_data;
1191         struct videobuf_queue *q = map->q;
1192         int i;
1193
1194         dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
1195                 map->count,vma->vm_start,vma->vm_end);
1196
1197         map->count--;
1198         if (0 == map->count) {
1199                 dprintk(1,"munmap %p q=%p\n",map,q);
1200                 mutex_lock(&q->lock);
1201                 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1202                         if (NULL == q->bufs[i])
1203                                 continue;
1204                         if (q->bufs[i])
1205                                 ;
1206                         if (q->bufs[i]->map != map)
1207                                 continue;
1208                         q->bufs[i]->map   = NULL;
1209                         q->bufs[i]->baddr = 0;
1210                         q->ops->buf_release(q,q->bufs[i]);
1211                 }
1212                 mutex_unlock(&q->lock);
1213                 kfree(map);
1214         }
1215         return;
1216 }
1217
1218 /*
1219  * Get a anonymous page for the mapping.  Make sure we can DMA to that
1220  * memory location with 32bit PCI devices (i.e. don't use highmem for
1221  * now ...).  Bounce buffers don't work very well for the data rates
1222  * video capture has.
1223  */
1224 static struct page*
1225 videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
1226                    int *type)
1227 {
1228         struct page *page;
1229
1230         dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n",
1231                 vaddr,vma->vm_start,vma->vm_end);
1232         if (vaddr > vma->vm_end)
1233                 return NOPAGE_SIGBUS;
1234         page = alloc_page(GFP_USER | __GFP_DMA32);
1235         if (!page)
1236                 return NOPAGE_OOM;
1237         clear_user_page(page_address(page), vaddr, page);
1238         if (type)
1239                 *type = VM_FAULT_MINOR;
1240         return page;
1241 }
1242
1243 static struct vm_operations_struct videobuf_vm_ops =
1244 {
1245         .open     = videobuf_vm_open,
1246         .close    = videobuf_vm_close,
1247         .nopage   = videobuf_vm_nopage,
1248 };
1249
1250 int videobuf_mmap_setup(struct videobuf_queue *q,
1251                         unsigned int bcount, unsigned int bsize,
1252                         enum v4l2_memory memory)
1253 {
1254         unsigned int i;
1255         int err;
1256
1257         err = videobuf_mmap_free(q);
1258         if (0 != err)
1259                 return err;
1260
1261         for (i = 0; i < bcount; i++) {
1262                 q->bufs[i] = videobuf_alloc(q->msize);
1263                 q->bufs[i]->i      = i;
1264                 q->bufs[i]->input  = UNSET;
1265                 q->bufs[i]->memory = memory;
1266                 q->bufs[i]->bsize  = bsize;
1267                 switch (memory) {
1268                 case V4L2_MEMORY_MMAP:
1269                         q->bufs[i]->boff  = bsize * i;
1270                         break;
1271                 case V4L2_MEMORY_USERPTR:
1272                 case V4L2_MEMORY_OVERLAY:
1273                         /* nothing */
1274                         break;
1275                 }
1276         }
1277         dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
1278                 bcount,bsize);
1279         return 0;
1280 }
1281
1282 int videobuf_mmap_free(struct videobuf_queue *q)
1283 {
1284         int i;
1285
1286         for (i = 0; i < VIDEO_MAX_FRAME; i++)
1287                 if (q->bufs[i] && q->bufs[i]->map)
1288                         return -EBUSY;
1289         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1290                 if (NULL == q->bufs[i])
1291                         continue;
1292                 q->ops->buf_release(q,q->bufs[i]);
1293                 kfree(q->bufs[i]);
1294                 q->bufs[i] = NULL;
1295         }
1296         return 0;
1297 }
1298
1299 int videobuf_mmap_mapper(struct videobuf_queue *q,
1300                          struct vm_area_struct *vma)
1301 {
1302         struct videobuf_mapping *map;
1303         unsigned int first,last,size,i;
1304         int retval;
1305
1306         mutex_lock(&q->lock);
1307         retval = -EINVAL;
1308         if (!(vma->vm_flags & VM_WRITE)) {
1309                 dprintk(1,"mmap app bug: PROT_WRITE please\n");
1310                 goto done;
1311         }
1312         if (!(vma->vm_flags & VM_SHARED)) {
1313                 dprintk(1,"mmap app bug: MAP_SHARED please\n");
1314                 goto done;
1315         }
1316
1317         /* look for first buffer to map */
1318         for (first = 0; first < VIDEO_MAX_FRAME; first++) {
1319                 if (NULL == q->bufs[first])
1320                         continue;
1321                 if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
1322                         continue;
1323                 if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
1324                         break;
1325         }
1326         if (VIDEO_MAX_FRAME == first) {
1327                 dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
1328                         (vma->vm_pgoff << PAGE_SHIFT));
1329                 goto done;
1330         }
1331
1332         /* look for last buffer to map */
1333         for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
1334                 if (NULL == q->bufs[last])
1335                         continue;
1336                 if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
1337                         continue;
1338                 if (q->bufs[last]->map) {
1339                         retval = -EBUSY;
1340                         goto done;
1341                 }
1342                 size += q->bufs[last]->bsize;
1343                 if (size == (vma->vm_end - vma->vm_start))
1344                         break;
1345         }
1346         if (VIDEO_MAX_FRAME == last) {
1347                 dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n",
1348                         (vma->vm_end - vma->vm_start));
1349                 goto done;
1350         }
1351
1352         /* create mapping + update buffer list */
1353         retval = -ENOMEM;
1354         map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
1355         if (NULL == map)
1356                 goto done;
1357         for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) {
1358                 q->bufs[i]->map   = map;
1359                 q->bufs[i]->baddr = vma->vm_start + size;
1360         }
1361         map->count    = 1;
1362         map->start    = vma->vm_start;
1363         map->end      = vma->vm_end;
1364         map->q        = q;
1365         vma->vm_ops   = &videobuf_vm_ops;
1366         vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
1367         vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
1368         vma->vm_private_data = map;
1369         dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
1370                 map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
1371         retval = 0;
1372
1373  done:
1374         mutex_unlock(&q->lock);
1375         return retval;
1376 }
1377
1378 /* --------------------------------------------------------------------- */
1379
1380 EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
1381
1382 EXPORT_SYMBOL_GPL(videobuf_dma_init);
1383 EXPORT_SYMBOL_GPL(videobuf_dma_init_user);
1384 EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel);
1385 EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay);
1386 EXPORT_SYMBOL_GPL(videobuf_dma_map);
1387 EXPORT_SYMBOL_GPL(videobuf_dma_sync);
1388 EXPORT_SYMBOL_GPL(videobuf_dma_unmap);
1389 EXPORT_SYMBOL_GPL(videobuf_dma_free);
1390
1391 EXPORT_SYMBOL_GPL(videobuf_pci_dma_map);
1392 EXPORT_SYMBOL_GPL(videobuf_pci_dma_unmap);
1393
1394 EXPORT_SYMBOL_GPL(videobuf_alloc);
1395 EXPORT_SYMBOL_GPL(videobuf_waiton);
1396 EXPORT_SYMBOL_GPL(videobuf_iolock);
1397
1398 EXPORT_SYMBOL_GPL(videobuf_queue_init);
1399 EXPORT_SYMBOL_GPL(videobuf_queue_cancel);
1400 EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
1401
1402 EXPORT_SYMBOL_GPL(videobuf_next_field);
1403 EXPORT_SYMBOL_GPL(videobuf_status);
1404 EXPORT_SYMBOL_GPL(videobuf_reqbufs);
1405 EXPORT_SYMBOL_GPL(videobuf_querybuf);
1406 EXPORT_SYMBOL_GPL(videobuf_qbuf);
1407 EXPORT_SYMBOL_GPL(videobuf_dqbuf);
1408 EXPORT_SYMBOL_GPL(videobuf_streamon);
1409 EXPORT_SYMBOL_GPL(videobuf_streamoff);
1410
1411 EXPORT_SYMBOL_GPL(videobuf_read_start);
1412 EXPORT_SYMBOL_GPL(videobuf_read_stop);
1413 EXPORT_SYMBOL_GPL(videobuf_read_stream);
1414 EXPORT_SYMBOL_GPL(videobuf_read_one);
1415 EXPORT_SYMBOL_GPL(videobuf_poll_stream);
1416
1417 EXPORT_SYMBOL_GPL(videobuf_mmap_setup);
1418 EXPORT_SYMBOL_GPL(videobuf_mmap_free);
1419 EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);
1420
1421 /*
1422  * Local variables:
1423  * c-basic-offset: 8
1424  * End:
1425  */