drivers/media/video/video-buf.c

   1 /*
   2  * generic helper functions for video4linux capture buffers, to handle
   3  * memory management and PCI DMA.  Right now bttv + saa7134 use it.
   4  *
   5  * The functions expect the hardware being able to scatter gatter
   6  * (i.e. the buffers are not linear in physical memory, but fragmented
   7  * into PAGE_SIZE chunks).  They also assume the driver does not need
   8  * to touch the video data (thus it is probably not useful for USB 1.1
   9  * as data often must be uncompressed by the drivers).
  10  *
  11  * (c) 2001-2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs]
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  */
  18
  19 #include <linux/init.h>
  20 #include <linux/module.h>
  21 #include <linux/vmalloc.h>
  22 #include <linux/pagemap.h>
  23 #include <linux/slab.h>
  24 #include <linux/pci.h>
  25 #include <linux/interrupt.h>
  26 #include <asm/page.h>
  27 #include <asm/pgtable.h>
  28
  29 #include <media/video-buf.h>
  30
  31 #define MAGIC_DMABUF 0x19721112
  32 #define MAGIC_BUFFER 0x20040302
  33 #define MAGIC_CHECK(is,should)  if (unlikely((is) != (should))) \
  34         { printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); }
  35
  36 static int debug = 0;
  37
  38 MODULE_DESCRIPTION("helper module to manage video4linux pci dma buffers");
  39 MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
  40 MODULE_LICENSE("GPL");
  41 MODULE_PARM(debug,"i");
  42
  43 #define dprintk(level, fmt, arg...)     if (debug >= level) \
  44         printk(KERN_DEBUG "vbuf: " fmt , ## arg)
  45
  46 struct scatterlist*
  47 videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages)
  48 {
  49         struct scatterlist *sglist;
  50         struct page *pg;
  51         int i;
  52
  53         sglist = kmalloc(sizeof(struct scatterlist)*nr_pages, GFP_KERNEL);
  54         if (NULL == sglist)
  55                 return NULL;
  56         memset(sglist,0,sizeof(struct scatterlist)*nr_pages);
  57         for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
  58                 pg = vmalloc_to_page(virt);
  59                 if (NULL == pg)
  60                         goto err;
  61                 if (PageHighMem(pg))
  62                         BUG();
  63                 sglist[i].page   = pg;
  64                 sglist[i].length = PAGE_SIZE;
  65         }
  66         return sglist;
  67
  68  err:
  69         kfree(sglist);
  70         return NULL;
  71 }
  72
  73 struct scatterlist*
  74 videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset)
  75 {
  76         struct scatterlist *sglist;
  77         int i = 0;
  78
  79         if (NULL == pages[0])
  80                 return NULL;
  81         sglist = kmalloc(sizeof(*sglist) * nr_pages, GFP_KERNEL);
  82         if (NULL == sglist)
  83                 return NULL;
  84         memset(sglist, 0, sizeof(*sglist) * nr_pages);
  85
  86         if (NULL == pages[0])
  87                 goto nopage;
  88         if (PageHighMem(pages[0]))
  89                 /* DMA to highmem pages might not work */
  90                 goto highmem;
  91         sglist[0].page   = pages[0];
  92         sglist[0].offset = offset;
  93         sglist[0].length = PAGE_SIZE - offset;
  94         for (i = 1; i < nr_pages; i++) {
  95                 if (NULL == pages[i])
  96                         goto nopage;
  97                 if (PageHighMem(pages[i]))
  98                         goto highmem;
  99                 sglist[i].page   = pages[i];
 100                 sglist[i].length = PAGE_SIZE;
 101         }
 102         return sglist;
 103
 104  nopage:
 105         dprintk(2,"sgl: oops - no page\n");
 106         kfree(sglist);
 107         return NULL;
 108
 109  highmem:
 110         dprintk(2,"sgl: oops - highmem page\n");
 111         kfree(sglist);
 112         return NULL;
 113 }
 114
 115 /* --------------------------------------------------------------------- */
 116
 117 void videobuf_dma_init(struct videobuf_dmabuf *dma)
 118 {
 119         memset(dma,0,sizeof(*dma));
 120         dma->magic = MAGIC_DMABUF;
 121 }
 122
 123 int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
 124                            unsigned long data, unsigned long size)
 125 {
 126         unsigned long first,last;
 127         int err, rw = 0;
 128
 129         dma->direction = direction;
 130         switch (dma->direction) {
 131         case PCI_DMA_FROMDEVICE: rw = READ;  break;
 132         case PCI_DMA_TODEVICE:   rw = WRITE; break;
 133         default:                 BUG();
 134         }
 135
 136         first = (data          & PAGE_MASK) >> PAGE_SHIFT;
 137         last  = ((data+size-1) & PAGE_MASK) >> PAGE_SHIFT;
 138         dma->offset   = data & ~PAGE_MASK;
 139         dma->nr_pages = last-first+1;
 140         dma->pages = kmalloc(dma->nr_pages * sizeof(struct page*),
 141                              GFP_KERNEL);
 142         if (NULL == dma->pages)
 143                 return -ENOMEM;
 144         dprintk(1,"init user [0x%lx+0x%lx => %d pages]\n",
 145                 data,size,dma->nr_pages);
 146
 147         down_read(&current->mm->mmap_sem);
 148         err = get_user_pages(current,current->mm,
 149                              data & PAGE_MASK, dma->nr_pages,
 150                              rw == READ, 1, /* force */
 151                              dma->pages, NULL);
 152         up_read(&current->mm->mmap_sem);
 153         if (err != dma->nr_pages) {
 154                 dma->nr_pages = (err >= 0) ? err : 0;
 155                 dprintk(1,"get_user_pages: err=%d [%d]\n",err,dma->nr_pages);
 156                 return err < 0 ? err : -EINVAL;
 157         }
 158         return 0;
 159 }
 160
 161 int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
 162                              int nr_pages)
 163 {
 164         dprintk(1,"init kernel [%d pages]\n",nr_pages);
 165         dma->direction = direction;
 166         dma->vmalloc = vmalloc_32(nr_pages << PAGE_SHIFT);
 167         if (NULL == dma->vmalloc) {
 168                 dprintk(1,"vmalloc_32(%d pages) failed\n",nr_pages);
 169                 return -ENOMEM;
 170         }
 171         memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT);
 172         dma->nr_pages = nr_pages;
 173         return 0;
 174 }
 175
 176 int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
 177                               dma_addr_t addr, int nr_pages)
 178 {
 179         dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n",
 180                 nr_pages,(unsigned long)addr);
 181         dma->direction = direction;
 182         if (0 == addr)
 183                 return -EINVAL;
 184
 185         dma->bus_addr = addr;
 186         dma->nr_pages = nr_pages;
 187         return 0;
 188 }
 189
 190 int videobuf_dma_pci_map(struct pci_dev *dev, struct videobuf_dmabuf *dma)
 191 {
 192         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 193         BUG_ON(0 == dma->nr_pages);
 194
 195         if (dma->pages) {
 196                 dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
 197                                                    dma->offset);
 198         }
 199         if (dma->vmalloc) {
 200                 dma->sglist = videobuf_vmalloc_to_sg
 201                         (dma->vmalloc,dma->nr_pages);
 202         }
 203         if (dma->bus_addr) {
 204                 dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
 205                 if (NULL != dma->sglist) {
 206                         dma->sglen  = 1;
 207                         sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK;
 208                         dma->sglist[0].offset           = dma->bus_addr & ~PAGE_MASK;
 209                         sg_dma_len(&dma->sglist[0])     = dma->nr_pages * PAGE_SIZE;
 210                 }
 211         }
 212         if (NULL == dma->sglist) {
 213                 dprintk(1,"scatterlist is NULL\n");
 214                 return -ENOMEM;
 215         }
 216
 217         if (!dma->bus_addr)
 218                 dma->sglen = pci_map_sg(dev,dma->sglist,dma->nr_pages,
 219                                         dma->direction);
 220         return 0;
 221 }
 222
 223 int videobuf_dma_pci_sync(struct pci_dev *dev, struct videobuf_dmabuf *dma)
 224 {
 225         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 226         BUG_ON(!dma->sglen);
 227
 228         if (!dma->bus_addr)
 229                 pci_dma_sync_sg_for_cpu(dev,dma->sglist,dma->nr_pages,dma->direction);
 230         return 0;
 231 }
 232
 233 int videobuf_dma_pci_unmap(struct pci_dev *dev, struct videobuf_dmabuf *dma)
 234 {
 235         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 236         if (!dma->sglen)
 237                 return 0;
 238
 239         if (!dma->bus_addr)
 240                 pci_unmap_sg(dev,dma->sglist,dma->nr_pages,dma->direction);
 241         kfree(dma->sglist);
 242         dma->sglist = NULL;
 243         dma->sglen = 0;
 244         return 0;
 245 }
 246
 247 int videobuf_dma_free(struct videobuf_dmabuf *dma)
 248 {
 249         MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
 250         BUG_ON(dma->sglen);
 251
 252         if (dma->pages) {
 253                 int i;
 254                 for (i=0; i < dma->nr_pages; i++)
 255                         page_cache_release(dma->pages[i]);
 256                 kfree(dma->pages);
 257                 dma->pages = NULL;
 258         }
 259         if (dma->vmalloc) {
 260                 vfree(dma->vmalloc);
 261                 dma->vmalloc = NULL;
 262         }
 263         if (dma->bus_addr) {
 264                 dma->bus_addr = 0;
 265         }
 266         dma->direction = PCI_DMA_NONE;
 267         return 0;
 268 }
 269
 270 /* --------------------------------------------------------------------- */
 271
 272 void* videobuf_alloc(unsigned int size)
 273 {
 274         struct videobuf_buffer *vb;
 275
 276         vb = kmalloc(size,GFP_KERNEL);
 277         if (NULL != vb) {
 278                 memset(vb,0,size);
 279                 videobuf_dma_init(&vb->dma);
 280                 init_waitqueue_head(&vb->done);
 281                 vb->magic     = MAGIC_BUFFER;
 282         }
 283         return vb;
 284 }
 285
 286 int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
 287 {
 288         int retval = 0;
 289         DECLARE_WAITQUEUE(wait, current);
 290
 291         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 292         add_wait_queue(&vb->done, &wait);
 293         while (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED) {
 294                 if (non_blocking) {
 295                         retval = -EAGAIN;
 296                         break;
 297                 }
 298                 set_current_state(intr  ? TASK_INTERRUPTIBLE
 299                                         : TASK_UNINTERRUPTIBLE);
 300                 if (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED)
 301                         schedule();
 302                 set_current_state(TASK_RUNNING);
 303                 if (intr && signal_pending(current)) {
 304                         dprintk(1,"buffer waiton: -EINTR\n");
 305                         retval = -EINTR;
 306                         break;
 307                 }
 308         }
 309         remove_wait_queue(&vb->done, &wait);
 310         return retval;
 311 }
 312
 313 int
 314 videobuf_iolock(struct pci_dev *pci, struct videobuf_buffer *vb,
 315                 struct v4l2_framebuffer *fbuf)
 316 {
 317         int err,pages;
 318         dma_addr_t bus;
 319
 320         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 321         switch (vb->memory) {
 322         case V4L2_MEMORY_MMAP:
 323         case V4L2_MEMORY_USERPTR:
 324                 if (0 == vb->baddr) {
 325                         /* no userspace addr -- kernel bounce buffer */
 326                         pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
 327                         err = videobuf_dma_init_kernel(&vb->dma,PCI_DMA_FROMDEVICE,
 328                                                        pages);
 329                         if (0 != err)
 330                                 return err;
 331                 } else {
 332                         /* dma directly to userspace */
 333                         err = videobuf_dma_init_user(&vb->dma,PCI_DMA_FROMDEVICE,
 334                                                      vb->baddr,vb->bsize);
 335                         if (0 != err)
 336                                 return err;
 337                 }
 338                 break;
 339         case V4L2_MEMORY_OVERLAY:
 340                 if (NULL == fbuf)
 341                         return -EINVAL;
 342                 /* FIXME: need sanity checks for vb->boff */
 343                 bus   = (dma_addr_t)fbuf->base + vb->boff;
 344                 pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
 345                 err = videobuf_dma_init_overlay(&vb->dma,PCI_DMA_FROMDEVICE,
 346                                                 bus, pages);
 347                 if (0 != err)
 348                         return err;
 349                 break;
 350         default:
 351                 BUG();
 352         }
 353         err = videobuf_dma_pci_map(pci,&vb->dma);
 354         if (0 != err)
 355                 return err;
 356
 357         return 0;
 358 }
 359
 360 /* --------------------------------------------------------------------- */
 361
 362 void
 363 videobuf_queue_init(struct videobuf_queue *q,
 364                     struct videobuf_queue_ops *ops,
 365                     struct pci_dev *pci,
 366                     spinlock_t *irqlock,
 367                     enum v4l2_buf_type type,
 368                     enum v4l2_field field,
 369                     unsigned int msize)
 370 {
 371         memset(q,0,sizeof(*q));
 372
 373         q->irqlock = irqlock;
 374         q->pci     = pci;
 375         q->type    = type;
 376         q->field   = field;
 377         q->msize   = msize;
 378         q->ops     = ops;
 379
 380         init_MUTEX(&q->lock);
 381         INIT_LIST_HEAD(&q->stream);
 382 }
 383
 384 int
 385 videobuf_queue_is_busy(struct videobuf_queue *q)
 386 {
 387         int i;
 388
 389         if (q->streaming) {
 390                 dprintk(1,"busy: streaming active\n");
 391                 return 1;
 392         }
 393         if (q->reading) {
 394                 dprintk(1,"busy: pending read #1\n");
 395                 return 1;
 396         }
 397         if (q->read_buf) {
 398                 dprintk(1,"busy: pending read #2\n");
 399                 return 1;
 400         }
 401         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 402                 if (NULL == q->bufs[i])
 403                         continue;
 404                 if (q->bufs[i]->map) {
 405                         dprintk(1,"busy: buffer #%d mapped\n",i);
 406                         return 1;
 407                 }
 408                 if (q->bufs[i]->state == STATE_QUEUED) {
 409                         dprintk(1,"busy: buffer #%d queued\n",i);
 410                         return 1;
 411                 }
 412                 if (q->bufs[i]->state == STATE_ACTIVE) {
 413                         dprintk(1,"busy: buffer #%d avtive\n",i);
 414                         return 1;
 415                 }
 416         }
 417         return 0;
 418 }
 419
 420 void
 421 videobuf_queue_cancel(struct file *file, struct videobuf_queue *q)
 422 {
 423         unsigned long flags;
 424         int i;
 425
 426         /* remove queued buffers from list */
 427         spin_lock_irqsave(q->irqlock,flags);
 428         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 429                 if (NULL == q->bufs[i])
 430                         continue;
 431                 if (q->bufs[i]->state == STATE_QUEUED) {
 432                         list_del(&q->bufs[i]->queue);
 433                         q->bufs[i]->state = STATE_ERROR;
 434                 }
 435         }
 436         spin_unlock_irqrestore(q->irqlock,flags);
 437
 438         /* free all buffers + clear queue */
 439         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 440                 if (NULL == q->bufs[i])
 441                         continue;
 442                 q->ops->buf_release(file,q->bufs[i]);
 443         }
 444         INIT_LIST_HEAD(&q->stream);
 445 }
 446
 447 /* --------------------------------------------------------------------- */
 448
 449 enum v4l2_field
 450 videobuf_next_field(struct videobuf_queue *q)
 451 {
 452         enum v4l2_field field = q->field;
 453
 454         BUG_ON(V4L2_FIELD_ANY == field);
 455
 456         if (V4L2_FIELD_ALTERNATE == field) {
 457                 if (V4L2_FIELD_TOP == q->last) {
 458                         field   = V4L2_FIELD_BOTTOM;
 459                         q->last = V4L2_FIELD_BOTTOM;
 460                 } else {
 461                         field   = V4L2_FIELD_TOP;
 462                         q->last = V4L2_FIELD_TOP;
 463                 }
 464         }
 465         return field;
 466 }
 467
 468 void
 469 videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb,
 470                 enum v4l2_buf_type type)
 471 {
 472         MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
 473
 474         b->index    = vb->i;
 475         b->type     = type;
 476
 477         b->memory   = vb->memory;
 478         switch (b->memory) {
 479         case V4L2_MEMORY_MMAP:
 480                 b->m.offset  = vb->boff;
 481                 b->length    = vb->bsize;
 482                 break;
 483         case V4L2_MEMORY_USERPTR:
 484                 b->m.userptr = vb->baddr;
 485                 b->length    = vb->bsize;
 486                 break;
 487         case V4L2_MEMORY_OVERLAY:
 488                 b->m.offset  = vb->boff;
 489                 break;
 490         }
 491
 492         b->flags    = 0;
 493         if (vb->map)
 494                 b->flags |= V4L2_BUF_FLAG_MAPPED;
 495
 496         switch (vb->state) {
 497         case STATE_PREPARED:
 498         case STATE_QUEUED:
 499         case STATE_ACTIVE:
 500                 b->flags |= V4L2_BUF_FLAG_QUEUED;
 501                 break;
 502         case STATE_DONE:
 503         case STATE_ERROR:
 504                 b->flags |= V4L2_BUF_FLAG_DONE;
 505                 break;
 506         case STATE_NEEDS_INIT:
 507         case STATE_IDLE:
 508                 /* nothing */
 509                 break;
 510         }
 511
 512         if (vb->input != UNSET) {
 513                 b->flags |= V4L2_BUF_FLAG_INPUT;
 514                 b->input  = vb->input;
 515         }
 516
 517         b->field     = vb->field;
 518         b->timestamp = vb->ts;
 519         b->bytesused = vb->size;
 520         b->sequence  = vb->field_count >> 1;
 521 }
 522
 523 int
 524 videobuf_reqbufs(struct file *file, struct videobuf_queue *q,
 525                  struct v4l2_requestbuffers *req)
 526 {
 527         unsigned int size,count;
 528         int retval;
 529
 530         if (req->type != q->type)
 531                 return -EINVAL;
 532         if (req->count < 1)
 533                 return -EINVAL;
 534         if (req->memory != V4L2_MEMORY_MMAP     &&
 535             req->memory != V4L2_MEMORY_USERPTR  &&
 536             req->memory != V4L2_MEMORY_OVERLAY)
 537                 return -EINVAL;
 538
 539         if (q->streaming)
 540                 return -EBUSY;
 541         if (!list_empty(&q->stream))
 542                 return -EBUSY;
 543
 544         down(&q->lock);
 545         count = req->count;
 546         if (count > VIDEO_MAX_FRAME)
 547                 count = VIDEO_MAX_FRAME;
 548         size = 0;
 549         q->ops->buf_setup(file,&count,&size);
 550         size = PAGE_ALIGN(size);
 551         dprintk(1,"reqbufs: bufs=%d, size=0x%x [%d pages total]\n",
 552                 count, size, (count*size)>>PAGE_SHIFT);
 553
 554         retval = videobuf_mmap_setup(file,q,count,size,req->memory);
 555         if (retval < 0)
 556                 goto done;
 557
 558         req->count = count;
 559
 560  done:
 561         up(&q->lock);
 562         return retval;
 563 }
 564
 565 int
 566 videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b)
 567 {
 568         if (unlikely(b->type != q->type))
 569                 return -EINVAL;
 570         if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME))
 571                 return -EINVAL;
 572         if (unlikely(NULL == q->bufs[b->index]))
 573                 return -EINVAL;
 574         videobuf_status(b,q->bufs[b->index],q->type);
 575         return 0;
 576 }
 577
 578 int
 579 videobuf_qbuf(struct file *file, struct videobuf_queue *q,
 580               struct v4l2_buffer *b)
 581 {
 582         struct videobuf_buffer *buf;
 583         enum v4l2_field field;
 584         unsigned long flags;
 585         int retval;
 586
 587         down(&q->lock);
 588         retval = -EBUSY;
 589         if (q->reading)
 590                 goto done;
 591         retval = -EINVAL;
 592         if (b->type != q->type)
 593                 goto done;
 594         if (b->index < 0 || b->index >= VIDEO_MAX_FRAME)
 595                 goto done;
 596         buf = q->bufs[b->index];
 597         if (NULL == buf)
 598                 goto done;
 599         MAGIC_CHECK(buf->magic,MAGIC_BUFFER);
 600         if (buf->memory != b->memory)
 601                 goto done;
 602         if (buf->state == STATE_QUEUED ||
 603             buf->state == STATE_ACTIVE)
 604                 goto done;
 605
 606         if (b->flags & V4L2_BUF_FLAG_INPUT) {
 607                 if (b->input >= q->inputs)
 608                         goto done;
 609                 buf->input = b->input;
 610         } else {
 611                 buf->input = UNSET;
 612         }
 613
 614         switch (b->memory) {
 615         case V4L2_MEMORY_MMAP:
 616                 if (0 == buf->baddr)
 617                         goto done;
 618                 break;
 619         case V4L2_MEMORY_USERPTR:
 620                 if (b->length < buf->bsize)
 621                         goto done;
 622                 if (STATE_NEEDS_INIT != buf->state && buf->baddr != b->m.userptr)
 623                         q->ops->buf_release(file,buf);
 624                 buf->baddr = b->m.userptr;
 625                 break;
 626         case V4L2_MEMORY_OVERLAY:
 627                 buf->boff = b->m.offset;
 628                 break;
 629         default:
 630                 goto done;
 631         }
 632
 633         field = videobuf_next_field(q);
 634         retval = q->ops->buf_prepare(file,buf,field);
 635         if (0 != retval)
 636                 goto done;
 637
 638         list_add_tail(&buf->stream,&q->stream);
 639         if (q->streaming) {
 640                 spin_lock_irqsave(q->irqlock,flags);
 641                 q->ops->buf_queue(file,buf);
 642                 spin_unlock_irqrestore(q->irqlock,flags);
 643         }
 644         retval = 0;
 645
 646  done:
 647         up(&q->lock);
 648         return retval;
 649 }
 650
 651 int
 652 videobuf_dqbuf(struct file *file, struct videobuf_queue *q,
 653                struct v4l2_buffer *b)
 654 {
 655         struct videobuf_buffer *buf;
 656         int retval;
 657
 658         down(&q->lock);
 659         retval = -EBUSY;
 660         if (q->reading)
 661                 goto done;
 662         retval = -EINVAL;
 663         if (b->type != q->type)
 664                 goto done;
 665         if (list_empty(&q->stream))
 666                 goto done;
 667         buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
 668         retval = videobuf_waiton(buf, file->f_flags & O_NONBLOCK, 1);
 669         if (retval < 0)
 670                 goto done;
 671         switch (buf->state) {
 672         case STATE_ERROR:
 673                 retval = -EIO;
 674                 /* fall through */
 675         case STATE_DONE:
 676                 videobuf_dma_pci_sync(q->pci,&buf->dma);
 677                 buf->state = STATE_IDLE;
 678                 break;
 679         default:
 680                 retval = -EINVAL;
 681                 goto done;
 682         }
 683         list_del(&buf->stream);
 684         memset(b,0,sizeof(*b));
 685         videobuf_status(b,buf,q->type);
 686
 687  done:
 688         up(&q->lock);
 689         return retval;
 690 }
 691
 692 int videobuf_streamon(struct file *file, struct videobuf_queue *q)
 693 {
 694         struct videobuf_buffer *buf;
 695         struct list_head *list;
 696         unsigned long flags;
 697         int retval;
 698
 699         down(&q->lock);
 700         retval = -EBUSY;
 701         if (q->reading)
 702                 goto done;
 703         retval = 0;
 704         if (q->streaming)
 705                 goto done;
 706         q->streaming = 1;
 707         spin_lock_irqsave(q->irqlock,flags);
 708         list_for_each(list,&q->stream) {
 709                 buf = list_entry(list, struct videobuf_buffer, stream);
 710                 if (buf->state == STATE_PREPARED)
 711                         q->ops->buf_queue(file,buf);
 712         }
 713         spin_unlock_irqrestore(q->irqlock,flags);
 714
 715  done:
 716         up(&q->lock);
 717         return retval;
 718 }
 719
 720 int videobuf_streamoff(struct file *file, struct videobuf_queue *q)
 721 {
 722         int retval = -EINVAL;
 723
 724         down(&q->lock);
 725         if (!q->streaming)
 726                 goto done;
 727         videobuf_queue_cancel(file,q);
 728         q->streaming = 0;
 729         retval = 0;
 730
 731  done:
 732         up(&q->lock);
 733         return retval;
 734 }
 735
 736 static ssize_t
 737 videobuf_read_zerocopy(struct file *file, struct videobuf_queue *q,
 738                        char __user *data, size_t count, loff_t *ppos)
 739 {
 740         enum v4l2_field field;
 741         unsigned long flags;
 742         int retval;
 743
 744         /* setup stuff */
 745         retval = -ENOMEM;
 746         q->read_buf = videobuf_alloc(q->msize);
 747         if (NULL == q->read_buf)
 748                 goto done;
 749
 750         q->read_buf->memory = V4L2_MEMORY_USERPTR;
 751         q->read_buf->baddr  = (unsigned long)data;
 752         q->read_buf->bsize  = count;
 753         field = videobuf_next_field(q);
 754         retval = q->ops->buf_prepare(file,q->read_buf,field);
 755         if (0 != retval)
 756                 goto done;
 757
 758         /* start capture & wait */
 759         spin_lock_irqsave(q->irqlock,flags);
 760         q->ops->buf_queue(file,q->read_buf);
 761         spin_unlock_irqrestore(q->irqlock,flags);
 762         retval = videobuf_waiton(q->read_buf,0,0);
 763         if (0 == retval) {
 764                 videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
 765                 if (STATE_ERROR == q->read_buf->state)
 766                         retval = -EIO;
 767                 else
 768                         retval = q->read_buf->size;
 769         }
 770
 771  done:
 772         /* cleanup */
 773         q->ops->buf_release(file,q->read_buf);
 774         kfree(q->read_buf);
 775         q->read_buf = NULL;
 776         return retval;
 777 }
 778
 779 ssize_t videobuf_read_one(struct file *file, struct videobuf_queue *q,
 780                           char __user *data, size_t count, loff_t *ppos)
 781 {
 782         enum v4l2_field field;
 783         unsigned long flags;
 784         unsigned size, nbufs, bytes;
 785         int retval;
 786
 787         down(&q->lock);
 788
 789         nbufs = 1; size = 0;
 790         q->ops->buf_setup(file,&nbufs,&size);
 791         if (NULL == q->read_buf  &&
 792             count >= size        &&
 793             !(file->f_flags & O_NONBLOCK)) {
 794                 retval = videobuf_read_zerocopy(file,q,data,count,ppos);
 795                 if (retval >= 0  ||  retval == -EIO)
 796                         /* ok, all done */
 797                         goto done;
 798                 /* fallback to kernel bounce buffer on failures */
 799         }
 800
 801         if (NULL == q->read_buf) {
 802                 /* need to capture a new frame */
 803                 retval = -ENOMEM;
 804                 q->read_buf = videobuf_alloc(q->msize);
 805                 if (NULL == q->read_buf)
 806                         goto done;
 807                 q->read_buf->memory = V4L2_MEMORY_USERPTR;
 808                 field = videobuf_next_field(q);
 809                 retval = q->ops->buf_prepare(file,q->read_buf,field);
 810                 if (0 != retval)
 811                         goto done;
 812                 spin_lock_irqsave(q->irqlock,flags);
 813                 q->ops->buf_queue(file,q->read_buf);
 814                 spin_unlock_irqrestore(q->irqlock,flags);
 815                 q->read_off = 0;
 816         }
 817
 818         /* wait until capture is done */
 819         retval = videobuf_waiton(q->read_buf, file->f_flags & O_NONBLOCK, 1);
 820         if (0 != retval)
 821                 goto done;
 822         videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
 823
 824         if (STATE_ERROR == q->read_buf->state) {
 825                 /* catch I/O errors */
 826                 q->ops->buf_release(file,q->read_buf);
 827                 kfree(q->read_buf);
 828                 q->read_buf = NULL;
 829                 retval = -EIO;
 830                 goto done;
 831         }
 832
 833         /* copy to userspace */
 834         bytes = count;
 835         if (bytes > q->read_buf->size - q->read_off)
 836                 bytes = q->read_buf->size - q->read_off;
 837         retval = -EFAULT;
 838         if (copy_to_user(data, q->read_buf->dma.vmalloc+q->read_off, bytes))
 839                 goto done;
 840
 841         retval = bytes;
 842         q->read_off += bytes;
 843         if (q->read_off == q->read_buf->size) {
 844                 /* all data copied, cleanup */
 845                 q->ops->buf_release(file,q->read_buf);
 846                 kfree(q->read_buf);
 847                 q->read_buf = NULL;
 848         }
 849
 850  done:
 851         up(&q->lock);
 852         return retval;
 853 }
 854
 855 int videobuf_read_start(struct file *file, struct videobuf_queue *q)
 856 {
 857         enum v4l2_field field;
 858         unsigned long flags;
 859         int count = 0, size = 0;
 860         int err, i;
 861
 862         q->ops->buf_setup(file,&count,&size);
 863         if (count < 2)
 864                 count = 2;
 865         if (count > VIDEO_MAX_FRAME)
 866                 count = VIDEO_MAX_FRAME;
 867         size = PAGE_ALIGN(size);
 868
 869         err = videobuf_mmap_setup(file, q, count, size, V4L2_MEMORY_USERPTR);
 870         if (err)
 871                 return err;
 872         for (i = 0; i < count; i++) {
 873                 field = videobuf_next_field(q);
 874                 err = q->ops->buf_prepare(file,q->bufs[i],field);
 875                 if (err)
 876                         return err;
 877                 list_add_tail(&q->bufs[i]->stream, &q->stream);
 878         }
 879         spin_lock_irqsave(q->irqlock,flags);
 880         for (i = 0; i < count; i++)
 881                 q->ops->buf_queue(file,q->bufs[i]);
 882         spin_unlock_irqrestore(q->irqlock,flags);
 883         q->reading = 1;
 884         return 0;
 885 }
 886
 887 void videobuf_read_stop(struct file *file, struct videobuf_queue *q)
 888 {
 889         int i;
 890
 891         videobuf_queue_cancel(file,q);
 892         INIT_LIST_HEAD(&q->stream);
 893         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
 894                 if (NULL == q->bufs[i])
 895                         continue;
 896                 kfree(q->bufs[i]);
 897                 q->bufs[i] = NULL;
 898         }
 899         q->read_buf = NULL;
 900         q->reading  = 0;
 901 }
 902
 903 ssize_t videobuf_read_stream(struct file *file, struct videobuf_queue *q,
 904                              char __user *data, size_t count, loff_t *ppos,
 905                              int vbihack)
 906 {
 907         unsigned int *fc, bytes;
 908         int err, retval;
 909         unsigned long flags;
 910
 911         down(&q->lock);
 912         retval = -EBUSY;
 913         if (q->streaming)
 914                 goto done;
 915         if (!q->reading) {
 916                 retval = videobuf_read_start(file,q);
 917                 if (retval < 0)
 918                         goto done;
 919         }
 920
 921         retval = 0;
 922         while (count > 0) {
 923                 /* get / wait for data */
 924                 if (NULL == q->read_buf) {
 925                         q->read_buf = list_entry(q->stream.next,
 926                                                  struct videobuf_buffer,
 927                                                  stream);
 928                         list_del(&q->read_buf->stream);
 929                         q->read_off = 0;
 930                 }
 931                 err = videobuf_waiton(q->read_buf,
 932                                       file->f_flags & O_NONBLOCK,1);
 933                 if (err < 0) {
 934                         if (0 == retval)
 935                                 retval = err;
 936                         break;
 937                 }
 938
 939                 if (q->read_buf->state == STATE_DONE) {
 940                         if (vbihack) {
 941                                 /* dirty, undocumented hack -- pass the frame counter
 942                                  * within the last four bytes of each vbi data block.
 943                                  * We need that one to maintain backward compatibility
 944                                  * to all vbi decoding software out there ... */
 945                                 fc  = (unsigned int*)q->read_buf->dma.vmalloc;
 946                                 fc += (q->read_buf->size>>2) -1;
 947                                 *fc = q->read_buf->field_count >> 1;
 948                                 dprintk(1,"vbihack: %d\n",*fc);
 949                         }
 950
 951                         /* copy stuff */
 952                         bytes = count;
 953                         if (bytes > q->read_buf->size - q->read_off)
 954                                 bytes = q->read_buf->size - q->read_off;
 955                         if (copy_to_user(data + retval,
 956                                          q->read_buf->dma.vmalloc + q->read_off,
 957                                          bytes)) {
 958                                 if (0 == retval)
 959                                         retval = -EFAULT;
 960                                 break;
 961                         }
 962                         count       -= bytes;
 963                         retval      += bytes;
 964                         q->read_off += bytes;
 965                 } else {
 966                         /* some error */
 967                         q->read_off = q->read_buf->size;
 968                         if (0 == retval)
 969                                 retval = -EIO;
 970                 }
 971
 972                 /* requeue buffer when done with copying */
 973                 if (q->read_off == q->read_buf->size) {
 974                         list_add_tail(&q->read_buf->stream,
 975                                       &q->stream);
 976                         spin_lock_irqsave(q->irqlock,flags);
 977                         q->ops->buf_queue(file,q->read_buf);
 978                         spin_unlock_irqrestore(q->irqlock,flags);
 979                         q->read_buf = NULL;
 980                 }
 981                 if (retval < 0)
 982                         break;
 983         }
 984
 985  done:
 986         up(&q->lock);
 987         return retval;
 988 }
 989
 990 unsigned int videobuf_poll_stream(struct file *file,
 991                                   struct videobuf_queue *q,
 992                                   poll_table *wait)
 993 {
 994         struct videobuf_buffer *buf = NULL;
 995         unsigned int rc = 0;
 996
 997         down(&q->lock);
 998         if (q->streaming) {
 999                 if (!list_empty(&q->stream))
1000                         buf = list_entry(q->stream.next,
1001                                          struct videobuf_buffer, stream);
1002         } else {
1003                 if (!q->reading)
1004                         videobuf_read_start(file,q);
1005                 if (!q->reading) {
1006                         rc = POLLERR;
1007                 } else if (NULL == q->read_buf) {
1008                         q->read_buf = list_entry(q->stream.next,
1009                                                  struct videobuf_buffer,
1010                                                  stream);
1011                         list_del(&q->read_buf->stream);
1012                         q->read_off = 0;
1013                 }
1014                 buf = q->read_buf;
1015         }
1016         if (!buf)
1017                 rc = POLLERR;
1018
1019         if (0 == rc) {
1020                 poll_wait(file, &buf->done, wait);
1021                 if (buf->state == STATE_DONE ||
1022                     buf->state == STATE_ERROR)
1023                         rc = POLLIN|POLLRDNORM;
1024         }
1025         up(&q->lock);
1026         return rc;
1027 }
1028
1029 /* --------------------------------------------------------------------- */
1030
1031 static void
1032 videobuf_vm_open(struct vm_area_struct *vma)
1033 {
1034         struct videobuf_mapping *map = vma->vm_private_data;
1035
1036         dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
1037                 map->count,vma->vm_start,vma->vm_end);
1038         map->count++;
1039 }
1040
1041 static void
1042 videobuf_vm_close(struct vm_area_struct *vma)
1043 {
1044         struct videobuf_mapping *map = vma->vm_private_data;
1045         int i;
1046
1047         dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
1048                 map->count,vma->vm_start,vma->vm_end);
1049
1050         /* down(&fh->lock); FIXME */
1051         map->count--;
1052         if (0 == map->count) {
1053                 dprintk(1,"munmap %p\n",map);
1054                 for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1055                         if (NULL == map->q->bufs[i])
1056                                 continue;
1057                         if (map->q->bufs[i])
1058                                 ;
1059                         if (map->q->bufs[i]->map != map)
1060                                 continue;
1061                         map->q->bufs[i]->map   = NULL;
1062                         map->q->bufs[i]->baddr = 0;
1063                         map->q->ops->buf_release(vma->vm_file,map->q->bufs[i]);
1064                 }
1065                 kfree(map);
1066         }
1067         /* up(&fh->lock); FIXME */
1068         return;
1069 }
1070
1071 /*
1072  * Get a anonymous page for the mapping.  Make sure we can DMA to that
1073  * memory location with 32bit PCI devices (i.e. don't use highmem for
1074  * now ...).  Bounce buffers don't work very well for the data rates
1075  * video capture has.
1076  */
1077 static struct page*
1078 videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
1079                    int *type)
1080 {
1081         struct page *page;
1082
1083         dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n",
1084                 vaddr,vma->vm_start,vma->vm_end);
1085         if (vaddr > vma->vm_end)
1086                 return NOPAGE_SIGBUS;
1087         page = alloc_page(GFP_USER);
1088         if (!page)
1089                 return NOPAGE_OOM;
1090         clear_user_page(page_address(page), vaddr, page);
1091         if (type)
1092                 *type = VM_FAULT_MINOR;
1093         return page;
1094 }
1095
1096 static struct vm_operations_struct videobuf_vm_ops =
1097 {
1098         .open     = videobuf_vm_open,
1099         .close    = videobuf_vm_close,
1100         .nopage   = videobuf_vm_nopage,
1101 };
1102
1103 int videobuf_mmap_setup(struct file *file, struct videobuf_queue *q,
1104                         unsigned int bcount, unsigned int bsize,
1105                         enum v4l2_memory memory)
1106 {
1107         unsigned int i;
1108         int err;
1109
1110         err = videobuf_mmap_free(file,q);
1111         if (0 != err)
1112                 return err;
1113
1114         for (i = 0; i < bcount; i++) {
1115                 q->bufs[i] = videobuf_alloc(q->msize);
1116                 q->bufs[i]->i      = i;
1117                 q->bufs[i]->input  = UNSET;
1118                 q->bufs[i]->memory = memory;
1119                 q->bufs[i]->bsize  = bsize;
1120                 switch (memory) {
1121                 case V4L2_MEMORY_MMAP:
1122                         q->bufs[i]->boff  = bsize * i;
1123                         break;
1124                 case V4L2_MEMORY_USERPTR:
1125                 case V4L2_MEMORY_OVERLAY:
1126                         /* nothing */
1127                         break;
1128                 }
1129         }
1130         dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
1131                 bcount,bsize);
1132         return 0;
1133 }
1134
1135 int videobuf_mmap_free(struct file *file, struct videobuf_queue *q)
1136 {
1137         int i;
1138
1139         for (i = 0; i < VIDEO_MAX_FRAME; i++)
1140                 if (q->bufs[i] && q->bufs[i]->map)
1141                         return -EBUSY;
1142         for (i = 0; i < VIDEO_MAX_FRAME; i++) {
1143                 if (NULL == q->bufs[i])
1144                         continue;
1145                 q->ops->buf_release(file,q->bufs[i]);
1146                 kfree(q->bufs[i]);
1147                 q->bufs[i] = NULL;
1148         }
1149         return 0;
1150 }
1151
1152 int videobuf_mmap_mapper(struct vm_area_struct *vma,
1153                          struct videobuf_queue *q)
1154 {
1155         struct videobuf_mapping *map;
1156         unsigned int first,last,size,i;
1157         int retval;
1158
1159         down(&q->lock);
1160         retval = -EINVAL;
1161         if (!(vma->vm_flags & VM_WRITE)) {
1162                 dprintk(1,"mmap app bug: PROT_WRITE please\n");
1163                 goto done;
1164         }
1165         if (!(vma->vm_flags & VM_SHARED)) {
1166                 dprintk(1,"mmap app bug: MAP_SHARED please\n");
1167                 goto done;
1168         }
1169
1170         /* look for first buffer to map */
1171         for (first = 0; first < VIDEO_MAX_FRAME; first++) {
1172                 if (NULL == q->bufs[first])
1173                         continue;
1174                 if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
1175                         continue;
1176                 if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
1177                         break;
1178         }
1179         if (VIDEO_MAX_FRAME == first) {
1180                 dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
1181                         (vma->vm_pgoff << PAGE_SHIFT));
1182                 goto done;
1183         }
1184
1185         /* look for last buffer to map */
1186         for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
1187                 if (NULL == q->bufs[last])
1188                         continue;
1189                 if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
1190                         continue;
1191                 if (q->bufs[last]->map) {
1192                         retval = -EBUSY;
1193                         goto done;
1194                 }
1195                 size += q->bufs[last]->bsize;
1196                 if (size == (vma->vm_end - vma->vm_start))
1197                         break;
1198         }
1199         if (VIDEO_MAX_FRAME == last) {
1200                 dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n",
1201                         (vma->vm_end - vma->vm_start));
1202                 goto done;
1203         }
1204
1205         /* create mapping + update buffer list */
1206         retval = -ENOMEM;
1207         map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
1208         if (NULL == map)
1209                 goto done;
1210         for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) {
1211                 q->bufs[i]->map   = map;
1212                 q->bufs[i]->baddr = vma->vm_start + size;
1213         }
1214         map->count    = 1;
1215         map->start    = vma->vm_start;
1216         map->end      = vma->vm_end;
1217         map->q        = q;
1218         vma->vm_ops   = &videobuf_vm_ops;
1219         vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
1220         vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
1221         vma->vm_private_data = map;
1222         dprintk(1,"mmap %p: %08lx-%08lx pgoff %08lx bufs %d-%d\n",
1223                 map,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
1224         retval = 0;
1225
1226  done:
1227         up(&q->lock);
1228         return retval;
1229 }
1230
1231 /* --------------------------------------------------------------------- */
1232
1233 EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
1234
1235 EXPORT_SYMBOL_GPL(videobuf_dma_init);
1236 EXPORT_SYMBOL_GPL(videobuf_dma_init_user);
1237 EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel);
1238 EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay);
1239 EXPORT_SYMBOL_GPL(videobuf_dma_pci_map);
1240 EXPORT_SYMBOL_GPL(videobuf_dma_pci_sync);
1241 EXPORT_SYMBOL_GPL(videobuf_dma_pci_unmap);
1242 EXPORT_SYMBOL_GPL(videobuf_dma_free);
1243
1244 EXPORT_SYMBOL_GPL(videobuf_alloc);
1245 EXPORT_SYMBOL_GPL(videobuf_waiton);
1246 EXPORT_SYMBOL_GPL(videobuf_iolock);
1247
1248 EXPORT_SYMBOL_GPL(videobuf_queue_init);
1249 EXPORT_SYMBOL_GPL(videobuf_queue_cancel);
1250 EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
1251
1252 EXPORT_SYMBOL_GPL(videobuf_next_field);
1253 EXPORT_SYMBOL_GPL(videobuf_status);
1254 EXPORT_SYMBOL_GPL(videobuf_reqbufs);
1255 EXPORT_SYMBOL_GPL(videobuf_querybuf);
1256 EXPORT_SYMBOL_GPL(videobuf_qbuf);
1257 EXPORT_SYMBOL_GPL(videobuf_dqbuf);
1258 EXPORT_SYMBOL_GPL(videobuf_streamon);
1259 EXPORT_SYMBOL_GPL(videobuf_streamoff);
1260
1261 EXPORT_SYMBOL_GPL(videobuf_read_start);
1262 EXPORT_SYMBOL_GPL(videobuf_read_stop);
1263 EXPORT_SYMBOL_GPL(videobuf_read_stream);
1264 EXPORT_SYMBOL_GPL(videobuf_read_one);
1265 EXPORT_SYMBOL_GPL(videobuf_poll_stream);
1266
1267 EXPORT_SYMBOL_GPL(videobuf_mmap_setup);
1268 EXPORT_SYMBOL_GPL(videobuf_mmap_free);
1269 EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);
1270
1271 /*
1272  * Local variables:
1273  * c-basic-offset: 8
1274  * End:
1275  */