diff options
Diffstat (limited to 'drivers/staging/comedi/comedi_fops.c')
| -rw-r--r-- | drivers/staging/comedi/comedi_fops.c | 39 |
1 files changed, 26 insertions, 13 deletions
diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c index f6d1287c7b83..08d1bbbebf2d 100644 --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -2301,11 +2301,12 @@ static int comedi_mmap(struct file *file, struct vm_area_struct *vma) struct comedi_subdevice *s; struct comedi_async *async; struct comedi_buf_map *bm = NULL; + struct comedi_buf_page *buf; unsigned long start = vma->vm_start; unsigned long size; int n_pages; int i; - int retval; + int retval = 0; /* * 'trylock' avoids circular dependency with current->mm->mmap_sem @@ -2361,24 +2362,36 @@ static int comedi_mmap(struct file *file, struct vm_area_struct *vma) retval = -EINVAL; goto done; } - for (i = 0; i < n_pages; ++i) { - struct comedi_buf_page *buf = &bm->page_list[i]; + if (bm->dma_dir != DMA_NONE) { + /* + * DMA buffer was allocated as a single block. + * Address is in page_list[0]. + */ + buf = &bm->page_list[0]; + retval = dma_mmap_coherent(bm->dma_hw_dev, vma, buf->virt_addr, + buf->dma_addr, n_pages * PAGE_SIZE); + } else { + for (i = 0; i < n_pages; ++i) { + unsigned long pfn; + + buf = &bm->page_list[i]; + pfn = page_to_pfn(virt_to_page(buf->virt_addr)); + retval = remap_pfn_range(vma, start, pfn, PAGE_SIZE, + PAGE_SHARED); + if (retval) + break; - if (remap_pfn_range(vma, start, - page_to_pfn(virt_to_page(buf->virt_addr)), - PAGE_SIZE, PAGE_SHARED)) { - retval = -EAGAIN; - goto done; + start += PAGE_SIZE; } - start += PAGE_SIZE; } - vma->vm_ops = &comedi_vm_ops; - vma->vm_private_data = bm; + if (retval == 0) { + vma->vm_ops = &comedi_vm_ops; + vma->vm_private_data = bm; - vma->vm_ops->open(vma); + vma->vm_ops->open(vma); + } - retval = 0; done: up_read(&dev->attach_lock); comedi_buf_map_put(bm); /* put reference to buf map - okay if NULL */ |