[media] vb2: add vb2_get_unmapped_area in vb2 core

no mmu system needs get_unmapped_area file operations to do mmap

Signed-off-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/drivers/media/video/videobuf2-core.c b/drivers/media/video/videobuf2-core.c
index 9005dc9991a..979e544388c 100644
--- a/drivers/media/video/videobuf2-core.c
+++ b/drivers/media/video/videobuf2-core.c
@@ -1567,6 +1567,37 @@ int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma)
 }
 EXPORT_SYMBOL_GPL(vb2_mmap);
 
+#ifndef CONFIG_MMU
+unsigned long vb2_get_unmapped_area(struct vb2_queue *q,
+                                    unsigned long addr,
+                                    unsigned long len,
+                                    unsigned long pgoff,
+                                    unsigned long flags)
+{
+        unsigned long off = pgoff << PAGE_SHIFT;
+        struct vb2_buffer *vb;
+        unsigned int buffer, plane;
+        int ret;
+
+        if (q->memory != V4L2_MEMORY_MMAP) {
+                dprintk(1, "Queue is not currently set up for mmap\n");
+                return -EINVAL;
+        }
+
+        /*
+         * Find the plane corresponding to the offset passed by userspace.
+         */
+        ret = __find_plane_by_offset(q, off, &buffer, &plane);
+        if (ret)
+                return ret;
+
+        vb = q->bufs[buffer];
+
+        return (unsigned long)vb2_plane_vaddr(vb, plane);
+}
+EXPORT_SYMBOL_GPL(vb2_get_unmapped_area);
+#endif
+
 static int __vb2_init_fileio(struct vb2_queue *q, int read);
 static int __vb2_cleanup_fileio(struct vb2_queue *q);