V4L/DVB (7023): Fix a regresion left by changeset 7e65d6e8f6df

Changeset 7e65d6e8f6df removed a very bad hack on mmap(). However, the fixes
weren't considering usermap and overlay memory models. This were breaking
direct reading from /dev/video?, used mostly by mpeg aware drivers.

Thanks to Steven Toth <stoth@linuxtv.org> for reporting the issue and
bissecting it.

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

1 files changed, 8 insertions, 4 deletions

diff --git a/drivers/media/video/videobuf-core.c b/drivers/media/video/videobuf-core.c
index c3adbd686ffe..80a14da9acef 100644
--- a/drivers/media/video/videobuf-core.c
+++ b/drivers/media/video/videobuf-core.c
@@ -102,10 +102,14 @@ int videobuf_iolock(struct videobuf_queue *q, struct videobuf_buffer *vb,
            since mmap_mapper() method should be called before _iolock.
            On some cases, the mmap_mapper() is called only after scheduling.
          */
-        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;
+        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);