SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/media/video/videobuf-dma-sg.c

   1 /*
   2  * helper functions for PCI DMA video4linux capture buffers
   3  *
   4  * The functions expect the hardware being able to scatter gatter
   5  * (i.e. the buffers are not linear in physical memory, but fragmented
   6  * into PAGE_SIZE chunks).  They also assume the driver does not need
   7  * to touch the video data.
   8  *
   9  * (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org>
  10  *
  11  * Highly based on video-buf written originally by:
  12  * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org>
  13  * (c) 2006 Mauro Carvalho Chehab, <mchehab@infradead.org>
  14  * (c) 2006 Ted Walther and John Sokol
  15  *
  16  * This program is free software; you can redistribute it and/or modify
  17  * it under the terms of the GNU General Public License as published by
  18  * the Free Software Foundation; either version 2
  19  */
  20
  21 #include <linux/init.h>
  22 #include <linux/module.h>
  23 #include <linux/moduleparam.h>
  24 #include <linux/slab.h>
  25 #include <linux/interrupt.h>
  26
  27 #include <linux/pci.h>
  28 #include <linux/vmalloc.h>
  29 #include <linux/pagemap.h>
  30 #include <asm/page.h>
  31 #include <asm/pgtable.h>
  32
  33 #include <media/videobuf-dma-sg.h>
  34
  35 #define MAGIC_DMABUF 0x19721112
  36 #define MAGIC_SG_MEM 0x17890714
  37
  38 #define MAGIC_CHECK(is,should)  if (unlikely((is) != (should))) \
  39         { printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); }
  40
  41 static int debug = 0;
  42 module_param(debug, int, 0644);
  43
  44 MODULE_DESCRIPTION("helper module to manage video4linux pci dma sg buffers");
  45 MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>");
  46 MODULE_LICENSE("GPL");
  47
  48 #define dprintk(level, fmt, arg...)     if (debug >= level) \
  49         printk(KERN_DEBUG "vbuf-sg: " fmt , ## arg)
  50
  51 /* --------------------------------------------------------------------- */
  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 struct videobuf_dmabuf *videobuf_to_dma (struct videobuf_buffer *buf)
 122 {
 123         struct videbuf_pci_sg_memory *mem=buf->priv;
 124         BUG_ON (!mem);
 125
 126         MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
 127
 128         return &mem->dma;
 129 }
 130
 131 void videobuf_dma_init(struct videobuf_dmabuf *dma)
 132 {
 133         memset(dma,0,sizeof(*dma));
 134         dma->magic = MAGIC_DMABUF;
 135 }
 136
 137 static int videobuf_dma_init_user_locked(struct videobuf_dmabuf *dma,
 138                         int direction, unsigned long data, unsigned long size)
 139 {
 140         unsigned long first,last;
 141         int err, rw = 0;
 142
 143         dma->direction = direction;
 144         switch (dma->direction) {
 145         case PCI_DMA_FROMDEVICE: rw = READ;  break;
 146         case PCI_DMA_TODEVICE:   rw = WRITE; break;
 147         default:                 BUG();
 148         }
 149
 150         first = (data          & PAGE_MASK) >> PAGE_SHIFT;
 151         last  = ((data+size-1) & PAGE_MASK) >> PAGE_SHIFT;
 152         dma->offset   = data & ~PAGE_MASK;
 153         dma->nr_pages = last-first+1;
 154         dma->pages = kmalloc(dma->nr_pages * sizeof(struct page*),
 155                              GFP_KERNEL);
 156         if (NULL == dma->pages)
 157                 return -ENOMEM;
 158         dprintk(1,"init user [0x%lx+0x%lx => %d pages]\n",
 159                 data,size,dma->nr_pages);
 160
 161         dma->varea = (void *) data;
 162
 163
 164         err = get_user_pages(current,current->mm,
 165                              data & PAGE_MASK, dma->nr_pages,
 166                              rw == READ, 1, /* force */
 167                              dma->pages, NULL);
 168
 169         if (err != dma->nr_pages) {
 170                 dma->nr_pages = (err >= 0) ? err : 0;
 171                 dprintk(1,"get_user_pages: err=%d [%d]\n",err,dma->nr_pages);
 172                 return err < 0 ? err : -EINVAL;
 173         }
 174         return 0;
 175 }
 176
 177 int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
 178                            unsigned long data, unsigned long size)
 179 {
 180         int ret;
 181         down_read(&current->mm->mmap_sem);
 182         ret = videobuf_dma_init_user_locked(dma, direction, data, size);
 183         up_read(&current->mm->mmap_sem);
 184
 185         return ret;
 186 }
 187
 188 int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
 189                              int nr_pages)
 190 {
 191         dprintk(1,"init kernel [%d pages]\n",nr_pages);
 192         dma->direction = direction;
 193         dma->vmalloc = vmalloc_32(nr_pages << PAGE_SHIFT);
 194         if (NULL == dma->vmalloc) {
 195                 dprintk(1,"vmalloc_32(%d pages) failed\n",nr_pages);
 196                 return -ENOMEM;
 197         }
 198         dprintk(1,"vmalloc is at addr 0x%08lx, size=%d\n",
 199                                 (unsigned long)dma->vmalloc,
 200                                 nr_pages << PAGE_SHIFT);
 201         memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT);
 202         dma->nr_pages = nr_pages;
 203         return 0;
 204 }
 205
 206 int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
 207                               dma_addr_t addr, int nr_pages)
 208 {
 209         dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n",
 210                 nr_pages,(unsigned long)addr);
 211         dma->direction = direction;
 212         if (0 == addr)
 213                 return -EINVAL;
 214
 215         dma->bus_addr = addr;
 216         dma->nr_pages = nr_pages;
 217         return 0;
 218 }
 219
 220 int videobuf_dma_map(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
 221 {
 222         void                   *dev=q->dev;
 223
 224         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 225         BUG_ON(0 == dma->nr_pages);
 226
 227         if (dma->pages) {
 228                 dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
 229                                                    dma->offset);
 230         }
 231         if (dma->vmalloc) {
 232                 dma->sglist = videobuf_vmalloc_to_sg
 233                                                 (dma->vmalloc,dma->nr_pages);
 234         }
 235         if (dma->bus_addr) {
 236                 dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
 237                 if (NULL != dma->sglist) {
 238                         dma->sglen  = 1;
 239                         sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK;
 240                         dma->sglist[0].offset           = dma->bus_addr & ~PAGE_MASK;
 241                         sg_dma_len(&dma->sglist[0])     = dma->nr_pages * PAGE_SIZE;
 242                 }
 243         }
 244         if (NULL == dma->sglist) {
 245                 dprintk(1,"scatterlist is NULL\n");
 246                 return -ENOMEM;
 247         }
 248         if (!dma->bus_addr) {
 249                 dma->sglen = pci_map_sg(dev,dma->sglist,
 250                                         dma->nr_pages, dma->direction);
 251                 if (0 == dma->sglen) {
 252                         printk(KERN_WARNING
 253                                "%s: videobuf_map_sg failed\n",__FUNCTION__);
 254                         kfree(dma->sglist);
 255                         dma->sglist = NULL;
 256                         dma->sglen = 0;
 257                         return -EIO;
 258                 }
 259         }
 260         return 0;
 261 }
 262
 263 int videobuf_dma_sync(struct videobuf_queue *q,struct videobuf_dmabuf *dma)
 264 {
 265         void                   *dev=q->dev;
 266
 267         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 268         BUG_ON(!dma->sglen);
 269
 270         pci_dma_sync_sg_for_cpu (dev,dma->sglist,dma->nr_pages,dma->direction);
 271         return 0;
 272 }
 273
 274 int videobuf_dma_unmap(struct videobuf_queue* q,struct videobuf_dmabuf *dma)
 275 {
 276         void                   *dev=q->dev;
 277
 278         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 279         if (!dma->sglen)
 280                 return 0;
 281
 282         pci_unmap_sg (dev,dma->sglist,dma->nr_pages,dma->direction);
 283
 284         kfree(dma->sglist);
 285         dma->sglist = NULL;
 286         dma->sglen = 0;
 287         return 0;
 288 }
 289
 290 int videobuf_dma_free(struct videobuf_dmabuf *dma)
 291 {
 292         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 293         BUG_ON(dma->sglen);
 294
 295         if (dma->pages) {
 296                 int i;
 297                 for (i=0; i < dma->nr_pages; i++)
 298                         page_cache_release(dma->pages[i]);
 299                 kfree(dma->pages);
 300                 dma->pages = NULL;
 301         }
 302
 303         vfree(dma->vmalloc);
 304         dma->vmalloc = NULL;
 305         dma->varea = NULL;
 306
 307         if (dma->bus_addr) {
 308                 dma->bus_addr = 0;
 309         }
 310         dma->direction = PCI_DMA_NONE;
 311         return 0;
 312 }
 313
 314 /* --------------------------------------------------------------------- */
 315
 316 int videobuf_pci_dma_map(struct pci_dev *pci,struct videobuf_dmabuf *dma)
 317 {
 318         struct videobuf_queue q;
 319
 320         q.dev=pci;
 321
 322         return (videobuf_dma_map(&q,dma));
 323 }
 324
 325 int videobuf_pci_dma_unmap(struct pci_dev *pci,struct videobuf_dmabuf *dma)
 326 {
 327         struct videobuf_queue q;
 328
 329         q.dev=pci;
 330
 331         return (videobuf_dma_unmap(&q,dma));
 332 }
 333
 334 /* --------------------------------------------------------------------- */
 335
 336 static void
 337 videobuf_vm_open(struct vm_area_struct *vma)
 338 {
 339         struct videobuf_mapping *map = vma->vm_private_data;
 340
 341         dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
 342                 map->count,vma->vm_start,vma->vm_end);
 343         map->count++;
 344 }
 345
 346 static void
 347 videobuf_vm_close(struct vm_area_struct *vma)
 348 {
 349         struct videobuf_mapping *map = vma->vm_private_data;
 350         struct videobuf_queue *q = map->q;
 351         struct videbuf_pci_sg_memory *mem;
 352         int i;
 353
 354         dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
 355                 map->count,vma->vm_start,vma->vm_end);
 356
 357         map->count--;
 358         if (0 == map->count) {
 359                 dprintk(1,"munmap %p q=%p\n",map,q);
 360                 mutex_lock(&q->lock);
 361                 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 362                         if (NULL == q->bufs[i])
 363                                 continue;
 364                         mem=q->bufs[i]->priv;
 365
 366                         if (!mem)
 367                                 continue;
 368
 369                         MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
 370
 371                         if (q->bufs[i]->map != map)
 372                                 continue;
 373                         q->bufs[i]->map   = NULL;
 374                         q->bufs[i]->baddr = 0;
 375                         q->ops->buf_release(q,q->bufs[i]);
 376                 }
 377                 mutex_unlock(&q->lock);
 378                 kfree(map);
 379         }
 380         return;
 381 }
 382
 383 /*
 384  * Get a anonymous page for the mapping.  Make sure we can DMA to that
 385  * memory location with 32bit PCI devices (i.e. don't use highmem for
 386  * now ...).  Bounce buffers don't work very well for the data rates
 387  * video capture has.
 388  */
 389 static struct page*
 390 videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
 391                    int *type)
 392 {
 393         struct page *page;
 394
 395         dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n",
 396                 vaddr,vma->vm_start,vma->vm_end);
 397         if (vaddr > vma->vm_end)
 398                 return NOPAGE_SIGBUS;
 399         page = alloc_page(GFP_USER | __GFP_DMA32);
 400         if (!page)
 401                 return NOPAGE_OOM;
 402         clear_user_page(page_address(page), vaddr, page);
 403         if (type)
 404                 *type = VM_FAULT_MINOR;
 405         return page;
 406 }
 407
 408 static struct vm_operations_struct videobuf_vm_ops =
 409 {
 410         .open     = videobuf_vm_open,
 411         .close    = videobuf_vm_close,
 412         .nopage   = videobuf_vm_nopage,
 413 };
 414
 415 /* ---------------------------------------------------------------------
 416  * PCI handlers for the generic methods
 417  */
 418
 419 /* Allocated area consists on 3 parts:
 420         struct video_buffer
 421         struct <driver>_buffer (cx88_buffer, saa7134_buf, ...)
 422         struct videobuf_pci_sg_memory
 423  */
 424
 425 static void *__videobuf_alloc(size_t size)
 426 {
 427         struct videbuf_pci_sg_memory *mem;
 428         struct videobuf_buffer *vb;
 429
 430         vb = kzalloc(size+sizeof(*mem),GFP_KERNEL);
 431
 432         mem = vb->priv = ((char *)vb)+size;
 433         mem->magic=MAGIC_SG_MEM;
 434
 435         videobuf_dma_init(&mem->dma);
 436
 437         dprintk(1,"%s: allocated at %p(%ld+%ld) & %p(%ld)\n",
 438                 __FUNCTION__,vb,(long)sizeof(*vb),(long)size-sizeof(*vb),
 439                 mem,(long)sizeof(*mem));
 440
 441         return vb;
 442 }
 443
 444 static int __videobuf_iolock (struct videobuf_queue* q,
 445                               struct videobuf_buffer *vb,
 446                               struct v4l2_framebuffer *fbuf)
 447 {
 448         int err,pages;
 449         dma_addr_t bus;
 450         struct videbuf_pci_sg_memory *mem=vb->priv;
 451         BUG_ON(!mem);
 452
 453         MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
 454
 455         switch (vb->memory) {
 456         case V4L2_MEMORY_MMAP:
 457         case V4L2_MEMORY_USERPTR:
 458                 if (0 == vb->baddr) {
 459                         /* no userspace addr -- kernel bounce buffer */
 460                         pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
 461                         err = videobuf_dma_init_kernel( &mem->dma,
 462                                                         PCI_DMA_FROMDEVICE,
 463                                                         pages );
 464                         if (0 != err)
 465                                 return err;
 466                 } else if (vb->memory == V4L2_MEMORY_USERPTR) {
 467                         /* dma directly to userspace */
 468                         err = videobuf_dma_init_user( &mem->dma,
 469                                                       PCI_DMA_FROMDEVICE,
 470                                                       vb->baddr,vb->bsize );
 471                         if (0 != err)
 472                                 return err;
 473                 } else {
 474                         /* NOTE: HACK: videobuf_iolock on V4L2_MEMORY_MMAP
 475                         buffers can only be called from videobuf_qbuf
 476                         we take current->mm->mmap_sem there, to prevent
 477                         locking inversion, so don't take it here */
 478
 479                         err = videobuf_dma_init_user_locked(&mem->dma,
 480                                                       PCI_DMA_FROMDEVICE,
 481                                                       vb->baddr, vb->bsize);
 482                         if (0 != err)
 483                                 return err;
 484                 }
 485                 break;
 486         case V4L2_MEMORY_OVERLAY:
 487                 if (NULL == fbuf)
 488                         return -EINVAL;
 489                 /* FIXME: need sanity checks for vb->boff */
 490                 /*
 491                  * Using a double cast to avoid compiler warnings when
 492                  * building for PAE. Compiler doesn't like direct casting
 493                  * of a 32 bit ptr to 64 bit integer.
 494                  */
 495                 bus   = (dma_addr_t)(unsigned long)fbuf->base + vb->boff;
 496                 pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
 497                 err = videobuf_dma_init_overlay(&mem->dma,PCI_DMA_FROMDEVICE,
 498                                                 bus, pages);
 499                 if (0 != err)
 500                         return err;
 501                 break;
 502         default:
 503                 BUG();
 504         }
 505         err = videobuf_dma_map(q,&mem->dma);
 506         if (0 != err)
 507                 return err;
 508
 509         return 0;
 510 }
 511
 512 static int __videobuf_sync(struct videobuf_queue *q,
 513                            struct videobuf_buffer *buf)
 514 {
 515         struct videbuf_pci_sg_memory *mem=buf->priv;
 516         BUG_ON (!mem);
 517         MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
 518
 519         return  videobuf_dma_sync(q,&mem->dma);
 520 }
 521
 522 static int __videobuf_mmap_free(struct videobuf_queue *q)
 523 {
 524         int i;
 525
 526         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 527                 if (q->bufs[i]) {
 528                         if (q->bufs[i]->map)
 529                                 return -EBUSY;
 530                 }
 531         }
 532
 533         return 0;
 534 }
 535
 536 static int __videobuf_mmap_mapper(struct videobuf_queue *q,
 537                          struct vm_area_struct *vma)
 538 {
 539         struct videbuf_pci_sg_memory *mem;
 540         struct videobuf_mapping *map;
 541         unsigned int first,last,size,i;
 542         int retval;
 543
 544         retval = -EINVAL;
 545         if (!(vma->vm_flags & VM_WRITE)) {
 546                 dprintk(1,"mmap app bug: PROT_WRITE please\n");
 547                 goto done;
 548         }
 549         if (!(vma->vm_flags & VM_SHARED)) {
 550                 dprintk(1,"mmap app bug: MAP_SHARED please\n");
 551                 goto done;
 552         }
 553
 554         /* look for first buffer to map */
 555         for (first = 0; first < VIDEO_MAX_FRAME; first++) {
 556                 if (NULL == q->bufs[first])
 557                         continue;
 558                 mem=q->bufs[first]->priv;
 559                 BUG_ON (!mem);
 560                 MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
 561
 562                 if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
 563                         continue;
 564                 if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
 565                         break;
 566         }
 567         if (VIDEO_MAX_FRAME == first) {
 568                 dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
 569                         (vma->vm_pgoff << PAGE_SHIFT));
 570                 goto done;
 571         }
 572
 573         /* look for last buffer to map */
 574         for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
 575                 if (NULL == q->bufs[last])
 576                         continue;
 577                 if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
 578                         continue;
 579                 if (q->bufs[last]->map) {
 580                         retval = -EBUSY;
 581                         goto done;
 582                 }
 583                 size += q->bufs[last]->bsize;
 584                 if (size == (vma->vm_end - vma->vm_start))
 585                         break;
 586         }
 587         if (VIDEO_MAX_FRAME == last) {
 588                 dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n",
 589                         (vma->vm_end - vma->vm_start));
 590                 goto done;
 591         }
 592
 593         /* create mapping + update buffer list */
 594         retval = -ENOMEM;
 595         map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
 596         if (NULL == map)
 597                 goto done;
 598         for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) {
 599                 q->bufs[i]->map   = map;
 600                 q->bufs[i]->baddr = vma->vm_start + size;
 601         }
 602         map->count    = 1;
 603         map->start    = vma->vm_start;
 604         map->end      = vma->vm_end;
 605         map->q        = q;
 606         vma->vm_ops   = &videobuf_vm_ops;
 607         vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
 608         vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
 609         vma->vm_private_data = map;
 610         dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
 611                 map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
 612         retval = 0;
 613
 614  done:
 615         return retval;
 616 }
 617
 618 static int __videobuf_copy_to_user ( struct videobuf_queue *q,
 619                                 char __user *data, size_t count,
 620                                 int nonblocking )
 621 {
 622         struct videbuf_pci_sg_memory *mem=q->read_buf->priv;
 623         BUG_ON (!mem);
 624         MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
 625
 626         /* copy to userspace */
 627         if (count > q->read_buf->size - q->read_off)
 628                 count = q->read_buf->size - q->read_off;
 629
 630         if (copy_to_user(data, mem->dma.vmalloc+q->read_off, count))
 631                 return -EFAULT;
 632
 633         return count;
 634 }
 635
 636 static int __videobuf_copy_stream ( struct videobuf_queue *q,
 637                                 char __user *data, size_t count, size_t pos,
 638                                 int vbihack, int nonblocking )
 639 {
 640         unsigned int  *fc;
 641         struct videbuf_pci_sg_memory *mem=q->read_buf->priv;
 642         BUG_ON (!mem);
 643         MAGIC_CHECK(mem->magic,MAGIC_SG_MEM);
 644
 645         if (vbihack) {
 646                 /* dirty, undocumented hack -- pass the frame counter
 647                         * within the last four bytes of each vbi data block.
 648                         * We need that one to maintain backward compatibility
 649                         * to all vbi decoding software out there ... */
 650                 fc  = (unsigned int*)mem->dma.vmalloc;
 651                 fc += (q->read_buf->size>>2) -1;
 652                 *fc = q->read_buf->field_count >> 1;
 653                 dprintk(1,"vbihack: %d\n",*fc);
 654         }
 655
 656         /* copy stuff using the common method */
 657         count = __videobuf_copy_to_user (q,data,count,nonblocking);
 658
 659         if ( (count==-EFAULT) && (0 == pos) )
 660                 return -EFAULT;
 661
 662         return count;
 663 }
 664
 665 static struct videobuf_qtype_ops pci_ops = {
 666         .magic        = MAGIC_QTYPE_OPS,
 667
 668         .alloc        = __videobuf_alloc,
 669         .iolock       = __videobuf_iolock,
 670         .sync         = __videobuf_sync,
 671         .mmap_free    = __videobuf_mmap_free,
 672         .mmap_mapper  = __videobuf_mmap_mapper,
 673         .copy_to_user = __videobuf_copy_to_user,
 674         .copy_stream  = __videobuf_copy_stream,
 675 };
 676
 677 void *videobuf_pci_alloc (size_t size)
 678 {
 679         struct videobuf_queue q;
 680
 681         /* Required to make generic handler to call __videobuf_alloc */
 682         q.int_ops=&pci_ops;
 683
 684         q.msize=size;
 685
 686         return videobuf_alloc (&q);
 687 }
 688
 689 void videobuf_queue_pci_init(struct videobuf_queue* q,
 690                          struct videobuf_queue_ops *ops,
 691                          void *dev,
 692                          spinlock_t *irqlock,
 693                          enum v4l2_buf_type type,
 694                          enum v4l2_field field,
 695                          unsigned int msize,
 696                          void *priv)
 697 {
 698         videobuf_queue_core_init(q, ops, dev, irqlock, type, field, msize,
 699                                  priv, &pci_ops);
 700 }
 701
 702 /* --------------------------------------------------------------------- */
 703
 704 EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
 705
 706 EXPORT_SYMBOL_GPL(videobuf_to_dma);
 707 EXPORT_SYMBOL_GPL(videobuf_dma_init);
 708 EXPORT_SYMBOL_GPL(videobuf_dma_init_user);
 709 EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel);
 710 EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay);
 711 EXPORT_SYMBOL_GPL(videobuf_dma_map);
 712 EXPORT_SYMBOL_GPL(videobuf_dma_sync);
 713 EXPORT_SYMBOL_GPL(videobuf_dma_unmap);
 714 EXPORT_SYMBOL_GPL(videobuf_dma_free);
 715
 716 EXPORT_SYMBOL_GPL(videobuf_pci_dma_map);
 717 EXPORT_SYMBOL_GPL(videobuf_pci_dma_unmap);
 718 EXPORT_SYMBOL_GPL(videobuf_pci_alloc);
 719
 720 EXPORT_SYMBOL_GPL(videobuf_queue_pci_init);
 721
 722 /*
 723  * Local variables:
 724  * c-basic-offset: 8
 725  * End:
 726  */