From 69b95a3a80b44ebb71bf153e79bcb8580e1d3de5 Mon Sep 17 00:00:00 2001 From: Sylwester Nawrocki Date: Thu, 7 Feb 2013 18:36:12 -0300 Subject: [PATCH] [media] s3c-camif: Fail on insufficient number of allocated buffers Ensure the driver gets always at least its minimum required number of buffers allocated by checking actual number of allocated buffers in vb2_reqbufs(). And free any partially allocated buffer queue with signaling an error to user space. Without this patch applications may wait forever to dequeue a filled buffer, because the hardware didn't even start after VIDIOC_STREAMON, VIDIOC_QBUF calls, due to insufficient number of empty buffers. Reported-by: Alexander Nestorov Signed-off-by: Sylwester Nawrocki Signed-off-by: Mauro Carvalho Chehab --- drivers/media/platform/s3c-camif/camif-capture.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/media/platform/s3c-camif/camif-capture.c b/drivers/media/platform/s3c-camif/camif-capture.c index e91f350929eb..70438a0f62ae 100644 --- a/drivers/media/platform/s3c-camif/camif-capture.c +++ b/drivers/media/platform/s3c-camif/camif-capture.c @@ -934,12 +934,19 @@ static int s3c_camif_reqbufs(struct file *file, void *priv, vp->owner = NULL; ret = vb2_reqbufs(&vp->vb_queue, rb); - if (!ret) { - vp->reqbufs_count = rb->count; - if (vp->owner == NULL && rb->count > 0) - vp->owner = priv; + if (ret < 0) + return ret; + + if (rb->count && rb->count < CAMIF_REQ_BUFS_MIN) { + rb->count = 0; + vb2_reqbufs(&vp->vb_queue, rb); + ret = -ENOMEM; } + vp->reqbufs_count = rb->count; + if (vp->owner == NULL && rb->count > 0) + vp->owner = priv; + return ret; }