i810: switch to vm_mmap()

Weirdness around do_mmap() in there does not rely on ->mmap_sem for
exclusion, so no need to keep it under that.  As the result, we can
turn that do_mmap() into vm_mmap().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/drivers/gpu/drm/i810/i810_dma.c b/drivers/gpu/drm/i810/i810_dma.c
index f920fb5..fa94391 100644 (file)
--- a/drivers/gpu/drm/i810/i810_dma.c
+++ b/drivers/gpu/drm/i810/i810_dma.c
@@ -130,11 +130,10 @@ static int i810_map_buffer(struct drm_buf *buf, struct drm_file *file_priv)
                return -EINVAL;
 
        /* This is all entirely broken */
-       down_write(&current->mm->mmap_sem);
        old_fops = file_priv->filp->f_op;
        file_priv->filp->f_op = &i810_buffer_fops;
        dev_priv->mmap_buffer = buf;
-       buf_priv->virtual = (void *)do_mmap(file_priv->filp, 0, buf->total,
+       buf_priv->virtual = (void *)vm_mmap(file_priv->filp, 0, buf->total,
                                            PROT_READ | PROT_WRITE,
                                            MAP_SHARED, buf->bus_address);
        dev_priv->mmap_buffer = NULL;
@@ -145,7 +144,6 @@ static int i810_map_buffer(struct drm_buf *buf, struct drm_file *file_priv)
                retcode = PTR_ERR(buf_priv->virtual);
                buf_priv->virtual = NULL;
        }
-       up_write(&current->mm->mmap_sem);
 
        return retcode;
 }