videobuf: revert changeset #7490:5b77f099a151

From: Mauro Carvalho Chehab <mchehab@infradead.org>

This changeset were supposed to optimize mmap() support on vmalloc. However, it
just broke mmap() on real devices. Revert the changeset to make mmap() to work
again.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 17 insertions, 12 deletions

diff --git a/linux/drivers/media/video/videobuf-core.c b/linux/drivers/media/video/videobuf-core.c
index 7138410fa..52d9a766c 100644
--- a/linux/drivers/media/video/videobuf-core.c
+++ b/linux/drivers/media/video/videobuf-core.c
@@ -92,17 +92,25 @@ int videobuf_iolock(struct videobuf_queue *q, struct videobuf_buffer *vb,
 	MAGIC_CHECK(vb->magic, MAGIC_BUFFER);
 	MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
 
+	/* This is required to avoid OOPS on some cases,
+	   since mmap_mapper() method should be called before _iolock.
+	   On some cases, the mmap_mapper() is called only after scheduling.
+	 */
+	if (vb->memory == V4L2_MEMORY_MMAP) {
+		wait_event_timeout(vb->done, q->is_mmapped,
+				   msecs_to_jiffies(100));
+		if (!q->is_mmapped) {
+			printk(KERN_ERR
+			       "Error: mmap_mapper() never called!\n");
+			return -EINVAL;
+		}
+	}
+
 	return CALL(q, iolock, q, vb, fbuf);
 }
 
 /* --------------------------------------------------------------------- */
 
-static int videobuf_mmap_setup_default(struct videobuf_queue *q,
-					struct videobuf_buffer *vb)
-{
-	return 0;
-}
-
 
 void videobuf_queue_core_init(struct videobuf_queue *q,
 			 struct videobuf_queue_ops *ops,
@@ -124,9 +132,6 @@ void videobuf_queue_core_init(struct videobuf_queue *q,
 	q->priv_data = priv;
 	q->int_ops   = int_ops;
 
-	if (!q->int_ops->mmap_setup)
-		q->int_ops->mmap_setup = videobuf_mmap_setup_default;
-
 	/* All buffer operations are mandatory */
 	BUG_ON(!q->ops->buf_setup);
 	BUG_ON(!q->ops->buf_prepare);
@@ -304,6 +309,8 @@ static int __videobuf_mmap_free(struct videobuf_queue *q)
 
 	rc  = CALL(q, mmap_free, q);
 
+	q->is_mmapped = 0;
+
 	if (rc < 0)
 		return rc;
 
@@ -355,9 +362,6 @@ static int __videobuf_mmap_setup(struct videobuf_queue *q,
 		switch (memory) {
 		case V4L2_MEMORY_MMAP:
 			q->bufs[i]->boff  = bsize * i;
-			err = q->int_ops->mmap_setup(q, q->bufs[i]);
-			if (err)
-				break;
 			break;
 		case V4L2_MEMORY_USERPTR:
 		case V4L2_MEMORY_OVERLAY:
@@ -1080,6 +1084,7 @@ int videobuf_mmap_mapper(struct videobuf_queue *q,
 
 	mutex_lock(&q->vb_lock);
 	retval = CALL(q, mmap_mapper, q, vma);
+	q->is_mmapped = 1;
 	mutex_unlock(&q->vb_lock);
 
 	return retval;