V4L/DVB: videobuf: add queue argument to videobuf_waiton()

videobuf_waiton() must unlock and relock ext_lock if it has to wait.
For that to happen it needs the videobuf_queue pointer.

Don't attempt to unlock/relock q->ext_lock unless it was locked in the
first place.

vb->state has to be protected by a spinlock to be safe.

This patch is based on code from Mauro Carvalho Chehab <mchehab@redhat.com>.

[mchehab@redhat.com: add extra argument to a few missing places]
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/common/saa7146_fops.c

@@ -56,7 +56,7 @@ void saa7146_dma_free(struct saa7146_dev *dev,struct videobuf_queue *q,
 
 	BUG_ON(in_interrupt());
 
-	videobuf_waiton(&buf->vb,0,0);
+	videobuf_waiton(q, &buf->vb, 0, 0);
 	videobuf_dma_unmap(q->dev, dma);
 	videobuf_dma_free(dma);
 	buf->vb.state = VIDEOBUF_NEEDS_INIT;

drivers/media/video/bt8xx/bttv-risc.c

@@ -582,7 +582,7 @@ bttv_dma_free(struct videobuf_queue *q,struct bttv *btv, struct bttv_buffer *buf
 	struct videobuf_dmabuf *dma=videobuf_to_dma(&buf->vb);
 
 	BUG_ON(in_interrupt());
-	videobuf_waiton(&buf->vb,0,0);
+	videobuf_waiton(q, &buf->vb, 0, 0);
 	videobuf_dma_unmap(q->dev, dma);
 	videobuf_dma_free(dma);
 	btcx_riscmem_free(btv->c.pci,&buf->bottom);

drivers/media/video/cx23885/cx23885-core.c

@@ -1221,7 +1221,7 @@ void cx23885_free_buffer(struct videobuf_queue *q, struct cx23885_buffer *buf)
 	struct videobuf_dmabuf *dma = videobuf_to_dma(&buf->vb);
 
 	BUG_ON(in_interrupt());
-	videobuf_waiton(&buf->vb, 0, 0);
+	videobuf_waiton(q, &buf->vb, 0, 0);
 	videobuf_dma_unmap(q->dev, dma);
 	videobuf_dma_free(dma);
 	btcx_riscmem_free(to_pci_dev(q->dev), &buf->risc);

drivers/media/video/cx88/cx88-core.c

@@ -217,7 +217,7 @@ cx88_free_buffer(struct videobuf_queue *q, struct cx88_buffer *buf)
 	struct videobuf_dmabuf *dma=videobuf_to_dma(&buf->vb);
 
 	BUG_ON(in_interrupt());
-	videobuf_waiton(&buf->vb,0,0);
+	videobuf_waiton(q, &buf->vb, 0, 0);
 	videobuf_dma_unmap(q->dev, dma);
 	videobuf_dma_free(dma);
 	btcx_riscmem_free(to_pci_dev(q->dev), &buf->risc);

drivers/media/video/fsl-viu.c

@@ -426,7 +426,7 @@ static void free_buffer(struct videobuf_queue *vq, struct viu_buf *buf)
 
 	BUG_ON(in_interrupt());
 
-	videobuf_waiton(&buf->vb, 0, 0);
+	videobuf_waiton(vq, &buf->vb, 0, 0);
 
 	if (vq->int_ops && vq->int_ops->vaddr)
 		vaddr = vq->int_ops->vaddr(vb);

drivers/media/video/mem2mem_testdev.c

@@ -848,7 +848,7 @@ static void queue_init(void *priv, struct videobuf_queue *vq,
 
 	videobuf_queue_vmalloc_init(vq, &m2mtest_qops, ctx->dev->v4l2_dev.dev,
 				    &ctx->dev->irqlock, type, V4L2_FIELD_NONE,
-				    sizeof(struct m2mtest_buffer), priv);
+				    sizeof(struct m2mtest_buffer), priv, NULL);
 }
 
 

drivers/media/video/mx1_camera.c

@@ -161,7 +161,7 @@ static void free_buffer(struct videobuf_queue *vq, struct mx1_buffer *buf)
 	 * This waits until this buffer is out of danger, i.e., until it is no
 	 * longer in STATE_QUEUED or STATE_ACTIVE
 	 */
-	videobuf_waiton(vb, 0, 0);
+	videobuf_waiton(vq, vb, 0, 0);
 	videobuf_dma_contig_free(vq, vb);
 
 	vb->state = VIDEOBUF_NEEDS_INIT;

drivers/media/video/mx2_camera.c

@@ -463,7 +463,7 @@ static void free_buffer(struct videobuf_queue *vq, struct mx2_buffer *buf)
 	 * This waits until this buffer is out of danger, i.e., until it is no
 	 * longer in STATE_QUEUED or STATE_ACTIVE
 	 */
-	videobuf_waiton(vb, 0, 0);
+	videobuf_waiton(vq, vb, 0, 0);
 
 	videobuf_dma_contig_free(vq, vb);
 	dev_dbg(&icd->dev, "%s freed\n", __func__);

drivers/media/video/mx3_camera.c

@@ -185,7 +185,7 @@ static void free_buffer(struct videobuf_queue *vq, struct mx3_camera_buffer *buf
 	 * This waits until this buffer is out of danger, i.e., until it is no
 	 * longer in STATE_QUEUED or STATE_ACTIVE
 	 */
-	videobuf_waiton(vb, 0, 0);
+	videobuf_waiton(vq, vb, 0, 0);
 	if (txd) {
 		ichan = to_idmac_chan(txd->chan);
 		async_tx_ack(txd);

drivers/media/video/omap24xxcam.c

@@ -420,7 +420,7 @@ static void omap24xxcam_vbq_release(struct videobuf_queue *vbq,
 	struct videobuf_dmabuf *dma = videobuf_to_dma(vb);
 
 	/* wait for buffer, especially to get out of the sgdma queue */
-	videobuf_waiton(vb, 0, 0);
+	videobuf_waiton(vbq, vb, 0, 0);
 	if (vb->memory == V4L2_MEMORY_MMAP) {
 		dma_unmap_sg(vbq->dev, dma->sglist, dma->sglen,
 			     dma->direction);

drivers/media/video/pxa_camera.c

@@ -275,7 +275,7 @@ static void free_buffer(struct videobuf_queue *vq, struct pxa_buffer *buf)
 	 * This waits until this buffer is out of danger, i.e., until it is no
 	 * longer in STATE_QUEUED or STATE_ACTIVE
 	 */
-	videobuf_waiton(&buf->vb, 0, 0);
+	videobuf_waiton(vq, &buf->vb, 0, 0);
 	videobuf_dma_unmap(vq->dev, dma);
 	videobuf_dma_free(dma);
 

drivers/media/video/saa7134/saa7134-core.c

@@ -255,7 +255,7 @@ void saa7134_dma_free(struct videobuf_queue *q,struct saa7134_buf *buf)
 	struct videobuf_dmabuf *dma=videobuf_to_dma(&buf->vb);
 	BUG_ON(in_interrupt());
 
-	videobuf_waiton(&buf->vb,0,0);
+	videobuf_waiton(q, &buf->vb, 0, 0);
 	videobuf_dma_unmap(q->dev, dma);
 	videobuf_dma_free(dma);
 	buf->vb.state = VIDEOBUF_NEEDS_INIT;

drivers/media/video/sh_mobile_ceu_camera.c

@@ -245,7 +245,7 @@ static void free_buffer(struct videobuf_queue *vq,
 	if (in_interrupt())
 		BUG();
 
-	videobuf_waiton(&buf->vb, 0, 0);
+	videobuf_waiton(vq, &buf->vb, 0, 0);
 	videobuf_dma_contig_free(vq, &buf->vb);
 	dev_dbg(dev, "%s freed\n", __func__);
 	buf->vb.state = VIDEOBUF_NEEDS_INIT;

drivers/media/video/sh_vou.c

@@ -230,7 +230,7 @@ static void free_buffer(struct videobuf_queue *vq, struct videobuf_buffer *vb)
 	BUG_ON(in_interrupt());
 
 	/* Wait until this buffer is no longer in STATE_QUEUED or STATE_ACTIVE */
-	videobuf_waiton(vb, 0, 0);
+	videobuf_waiton(vq, vb, 0, 0);
 	videobuf_dma_contig_free(vq, vb);
 	vb->state = VIDEOBUF_NEEDS_INIT;
 }

drivers/media/video/tlg2300/pd-video.c

@@ -1434,7 +1434,7 @@ static int pd_video_open(struct file *file)
 				V4L2_BUF_TYPE_VIDEO_CAPTURE,
 				V4L2_FIELD_INTERLACED,/* video is interlacd */
 				sizeof(struct videobuf_buffer),/*it's enough*/
-				front);
+				front, NULL);
 	} else if (vfd->vfl_type == VFL_TYPE_VBI
 		&& !(pd->state & POSEIDON_STATE_VBI)) {
 		front = kzalloc(sizeof(struct front_face), GFP_KERNEL);
@@ -1451,7 +1451,7 @@ static int pd_video_open(struct file *file)
 				V4L2_BUF_TYPE_VBI_CAPTURE,
 				V4L2_FIELD_NONE, /* vbi is NONE mode */
 				sizeof(struct videobuf_buffer),
-				front);
+				front, NULL);
 	} else {
 		/* maybe add FM support here */
 		log("other ");

drivers/media/video/videobuf-core.c

@@ -73,25 +73,46 @@ struct videobuf_buffer *videobuf_alloc_vb(struct videobuf_queue *q)
 }
 EXPORT_SYMBOL_GPL(videobuf_alloc_vb);
 
-#define WAITON_CONDITION (vb->state != VIDEOBUF_ACTIVE &&\
-				vb->state != VIDEOBUF_QUEUED)
-int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
+static int is_state_active_or_queued(struct videobuf_queue *q, struct videobuf_buffer *vb)
 {
+	unsigned long flags;
+	bool rc;
+
+	spin_lock_irqsave(q->irqlock, flags);
+	rc = vb->state != VIDEOBUF_ACTIVE && vb->state != VIDEOBUF_QUEUED;
+	spin_unlock_irqrestore(q->irqlock, flags);
+	return rc;
+};
+
+int videobuf_waiton(struct videobuf_queue *q, struct videobuf_buffer *vb,
+		int non_blocking, int intr)
+{
+	bool is_ext_locked;
+	int ret = 0;
+
 	MAGIC_CHECK(vb->magic, MAGIC_BUFFER);
 
 	if (non_blocking) {
-		if (WAITON_CONDITION)
+		if (is_state_active_or_queued(q, vb))
 			return 0;
-		else
-			return -EAGAIN;
+		return -EAGAIN;
 	}
 
+	is_ext_locked = q->ext_lock && mutex_is_locked(q->ext_lock);
+
+	/* Release vdev lock to prevent this wait from blocking outside access to
+	   the device. */
+	if (is_ext_locked)
+		mutex_unlock(q->ext_lock);
 	if (intr)
-		return wait_event_interruptible(vb->done, WAITON_CONDITION);
+		ret = wait_event_interruptible(vb->done, is_state_active_or_queued(q, vb));
 	else
-		wait_event(vb->done, WAITON_CONDITION);
+		wait_event(vb->done, is_state_active_or_queued(q, vb));
+	/* Relock */
+	if (is_ext_locked)
+		mutex_lock(q->ext_lock);
 
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(videobuf_waiton);
 
@@ -671,7 +692,7 @@ static int stream_next_buffer(struct videobuf_queue *q,
 		goto done;
 
 	buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
-	retval = videobuf_waiton(buf, nonblocking, 1);
+	retval = videobuf_waiton(q, buf, nonblocking, 1);
 	if (retval < 0)
 		goto done;
 
@@ -799,7 +820,7 @@ static ssize_t videobuf_read_zerocopy(struct videobuf_queue *q,
 	spin_lock_irqsave(q->irqlock, flags);
 	q->ops->buf_queue(q, q->read_buf);
 	spin_unlock_irqrestore(q->irqlock, flags);
-	retval = videobuf_waiton(q->read_buf, 0, 0);
+	retval = videobuf_waiton(q, q->read_buf, 0, 0);
 	if (0 == retval) {
 		CALL(q, sync, q, q->read_buf);
 		if (VIDEOBUF_ERROR == q->read_buf->state)
@@ -911,7 +932,7 @@ ssize_t videobuf_read_one(struct videobuf_queue *q,
 	}
 
 	/* wait until capture is done */
-	retval = videobuf_waiton(q->read_buf, nonblocking, 1);
+	retval = videobuf_waiton(q, q->read_buf, nonblocking, 1);
 	if (0 != retval)
 		goto done;
 
@@ -1061,7 +1082,7 @@ ssize_t videobuf_read_stream(struct videobuf_queue *q,
 			list_del(&q->read_buf->stream);
 			q->read_off = 0;
 		}
-		rc = videobuf_waiton(q->read_buf, nonblocking, 1);
+		rc = videobuf_waiton(q, q->read_buf, nonblocking, 1);
 		if (rc < 0) {
 			if (0 == retval)
 				retval = rc;

drivers/media/video/videobuf-dvb.c

@@ -57,7 +57,7 @@ static int videobuf_dvb_thread(void *data)
 		buf = list_entry(dvb->dvbq.stream.next,
 				 struct videobuf_buffer, stream);
 		list_del(&buf->stream);
-		err = videobuf_waiton(buf,0,1);
+		err = videobuf_waiton(&dvb->dvbq, buf, 0, 1);
 
 		/* no more feeds left or stop_feed() asked us to quit */
 		if (0 == dvb->nfeeds)

drivers/staging/cx25821/cx25821-core.c

@@ -1319,7 +1319,7 @@ void cx25821_free_buffer(struct videobuf_queue *q, struct cx25821_buffer *buf)
 	struct videobuf_dmabuf *dma = videobuf_to_dma(&buf->vb);
 
 	BUG_ON(in_interrupt());
-	videobuf_waiton(&buf->vb, 0, 0);
+	videobuf_waiton(q, &buf->vb, 0, 0);
 	videobuf_dma_unmap(q->dev, dma);
 	videobuf_dma_free(dma);
 	btcx_riscmem_free(to_pci_dev(q->dev), &buf->risc);

drivers/staging/dt3155v4l/dt3155v4l.c

@@ -293,7 +293,7 @@ static void
 dt3155_buf_release(struct videobuf_queue *q, struct videobuf_buffer *vb)
 {
 	if (vb->state == VIDEOBUF_ACTIVE)
-		videobuf_waiton(vb, 0, 0); /* FIXME: cannot be interrupted */
+		videobuf_waiton(q, vb, 0, 0); /* FIXME: cannot be interrupted */
 	videobuf_dma_contig_free(q, vb);
 	vb->state = VIDEOBUF_NEEDS_INIT;
 }
@@ -440,7 +440,7 @@ dt3155_open(struct file *filp)
 		videobuf_queue_dma_contig_init(pd->vidq, &vbq_ops,
 				&pd->pdev->dev, &pd->lock,
 				V4L2_BUF_TYPE_VIDEO_CAPTURE, V4L2_FIELD_NONE,
-				sizeof(struct videobuf_buffer), pd);
+				sizeof(struct videobuf_buffer), pd, NULL);
 		/* disable all irqs, clear all irq flags */
 		iowrite32(FLD_START | FLD_END_EVEN | FLD_END_ODD,
 						pd->regs + INT_CSR);
@@ -494,7 +494,7 @@ dt3155_release(struct file *filp)
 		tmp = pd->curr_buf;
 		spin_unlock_irqrestore(&pd->lock, flags);
 		if (tmp)
-			videobuf_waiton(tmp, 0, 1); /* block, interruptible */
+			videobuf_waiton(pd->vidq, tmp, 0, 1); /* block, interruptible */
 		dt3155_stop_acq(pd);
 		videobuf_stop(pd->vidq);
 		pd->acq_fp = NULL;
@@ -603,7 +603,7 @@ dt3155_ioc_streamoff(struct file *filp, void *p, enum v4l2_buf_type type)
 	tmp = pd->curr_buf;
 	spin_unlock_irqrestore(&pd->lock, flags);
 	if (tmp)
-		videobuf_waiton(tmp, 0, 1); /* block, interruptible */
+		videobuf_waiton(pd->vidq, tmp, 0, 1); /* block, interruptible */
 	return ret;
 }
 

include/media/videobuf-core.h

@@ -180,7 +180,8 @@ static inline void videobuf_queue_unlock(struct videobuf_queue *q)
 		mutex_unlock(&q->vb_lock);
 }
 
-int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr);
+int videobuf_waiton(struct videobuf_queue *q, struct videobuf_buffer *vb,
+		int non_blocking, int intr);
 int videobuf_iolock(struct videobuf_queue *q, struct videobuf_buffer *vb,
 		struct v4l2_framebuffer *fbuf);