* We already have buffers allocated, so first check if they
* are not in use and can be freed.
*/
+ mutex_lock(&q->mmap_lock);
if (q->memory == V4L2_MEMORY_MMAP && __buffers_in_use(q)) {
+ mutex_unlock(&q->mmap_lock);
dprintk(1, "memory in use, cannot free\n");
return -EBUSY;
}
*/
__vb2_queue_cancel(q);
ret = __vb2_queue_free(q, q->num_buffers);
+ mutex_unlock(&q->mmap_lock);
if (ret)
return ret;
*/
}
+ mutex_lock(&q->mmap_lock);
q->num_buffers = allocated_buffers;
if (ret < 0) {
* from q->num_buffers.
*/
__vb2_queue_free(q, allocated_buffers);
+ mutex_unlock(&q->mmap_lock);
return ret;
}
+ mutex_unlock(&q->mmap_lock);
/*
* Return the number of successfully allocated buffers
*/
}
+ mutex_lock(&q->mmap_lock);
q->num_buffers += allocated_buffers;
if (ret < 0) {
* from q->num_buffers.
*/
__vb2_queue_free(q, allocated_buffers);
+ mutex_unlock(&q->mmap_lock);
return -ENOMEM;
}
+ mutex_unlock(&q->mmap_lock);
/*
* Return the number of successfully allocated buffers
static int __buf_prepare(struct vb2_buffer *vb, const struct v4l2_buffer *b)
{
struct vb2_queue *q = vb->vb2_queue;
- struct rw_semaphore *mmap_sem;
int ret;
ret = __verify_length(vb, b);
ret = __qbuf_mmap(vb, b);
break;
case V4L2_MEMORY_USERPTR:
- /*
- * In case of user pointer buffers vb2 allocators need to get
- * direct access to userspace pages. This requires getting
- * the mmap semaphore for read access in the current process
- * structure. The same semaphore is taken before calling mmap
- * operation, while both qbuf/prepare_buf and mmap are called
- * by the driver or v4l2 core with the driver's lock held.
- * To avoid an AB-BA deadlock (mmap_sem then driver's lock in
- * mmap and driver's lock then mmap_sem in qbuf/prepare_buf),
- * the videobuf2 core releases the driver's lock, takes
- * mmap_sem and then takes the driver's lock again.
- */
- mmap_sem = ¤t->mm->mmap_sem;
- call_void_qop(q, wait_prepare, q);
- down_read(mmap_sem);
- call_void_qop(q, wait_finish, q);
-
ret = __qbuf_userptr(vb, b);
-
- up_read(mmap_sem);
break;
case V4L2_MEMORY_DMABUF:
ret = __qbuf_dmabuf(vb, b);
return -EINVAL;
}
+ mutex_lock(&q->mmap_lock);
ret = call_memop(vb, mmap, vb->planes[plane].mem_priv, vma);
+ mutex_unlock(&q->mmap_lock);
if (ret)
return ret;
unsigned long off = pgoff << PAGE_SHIFT;
struct vb2_buffer *vb;
unsigned int buffer, plane;
+ void *vaddr;
int ret;
if (q->memory != V4L2_MEMORY_MMAP) {
vb = q->bufs[buffer];
- return (unsigned long)vb2_plane_vaddr(vb, plane);
+ vaddr = vb2_plane_vaddr(vb, plane);
+ return vaddr ? (unsigned long)vaddr : -EINVAL;
}
EXPORT_SYMBOL_GPL(vb2_get_unmapped_area);
#endif
INIT_LIST_HEAD(&q->queued_list);
INIT_LIST_HEAD(&q->done_list);
spin_lock_init(&q->done_lock);
+ mutex_init(&q->mmap_lock);
init_waitqueue_head(&q->done_wq);
if (q->buf_struct_size == 0)
{
__vb2_cleanup_fileio(q);
__vb2_queue_cancel(q);
+ mutex_lock(&q->mmap_lock);
__vb2_queue_free(q, q->num_buffers);
+ mutex_unlock(&q->mmap_lock);
}
EXPORT_SYMBOL_GPL(vb2_queue_release);
int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma)
{
struct video_device *vdev = video_devdata(file);
- struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
- int err;
- if (lock && mutex_lock_interruptible(lock))
- return -ERESTARTSYS;
- err = vb2_mmap(vdev->queue, vma);
- if (lock)
- mutex_unlock(lock);
- return err;
+ return vb2_mmap(vdev->queue, vma);
}
EXPORT_SYMBOL_GPL(vb2_fop_mmap);
unsigned long len, unsigned long pgoff, unsigned long flags)
{
struct video_device *vdev = video_devdata(file);
- struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
- int ret;
- if (lock && mutex_lock_interruptible(lock))
- return -ERESTARTSYS;
- ret = vb2_get_unmapped_area(vdev->queue, addr, len, pgoff, flags);
- if (lock)
- mutex_unlock(lock);
- return ret;
+ return vb2_get_unmapped_area(vdev->queue, addr, len, pgoff, flags);
}
EXPORT_SYMBOL_GPL(vb2_fop_get_unmapped_area);
#endif
projects / users / hch / uuid.git / commitdiff