Commit bccce80b authored by Eric Farman's avatar Eric Farman Committed by Alex Williamson
Browse files

vfio-ccw: Wire in the request callback 



The device is being unplugged, so pass the request to userspace to
ask for a graceful cleanup. This should free up the thread that
would otherwise loop waiting for the device to be fully released.

Signed-off-by: default avatarEric Farman <farman@linux.ibm.com>
Reviewed-by: default avatarCornelia Huck <cohuck@redhat.com>
Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent a15ac665

drivers/s390/cio/vfio_ccw_ops.c

+26 −0
Original line number Diff line number Diff line
@@ -394,6 +394,7 @@ static int vfio_ccw_mdev_get_irq_info(struct vfio_irq_info *info) 
	switch (info->index) {

	case VFIO_CCW_IO_IRQ_INDEX:

	case VFIO_CCW_CRW_IRQ_INDEX:

	case VFIO_CCW_REQ_IRQ_INDEX:

		info->count = 1;

		info->flags = VFIO_IRQ_INFO_EVENTFD;

		break;
@@ -424,6 +425,9 @@ static int vfio_ccw_mdev_set_irqs(struct mdev_device *mdev, 
	case VFIO_CCW_CRW_IRQ_INDEX:

		ctx = &private->crw_trigger;

		break;

	case VFIO_CCW_REQ_IRQ_INDEX:

		ctx = &private->req_trigger;

		break;

	default:

		return -EINVAL;

	}
@@ -607,6 +611,27 @@ static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev, 
	}

}



/* Request removal of the device*/

static void vfio_ccw_mdev_request(struct mdev_device *mdev, unsigned int count)

{

	struct vfio_ccw_private *private = dev_get_drvdata(mdev_parent_dev(mdev));



	if (!private)

		return;



	if (private->req_trigger) {

		if (!(count % 10))

			dev_notice_ratelimited(mdev_dev(private->mdev),

					       "Relaying device request to user (#%u)\n",

					       count);



		eventfd_signal(private->req_trigger, 1);

	} else if (count == 0) {

		dev_notice(mdev_dev(private->mdev),

			   "No device request channel registered, blocked until released by user\n");

	}

}



static const struct mdev_parent_ops vfio_ccw_mdev_ops = {

	.owner			= THIS_MODULE,

	.supported_type_groups  = mdev_type_groups,
@@ -617,6 +642,7 @@ static const struct mdev_parent_ops vfio_ccw_mdev_ops = { 
	.read			= vfio_ccw_mdev_read,

	.write			= vfio_ccw_mdev_write,

	.ioctl			= vfio_ccw_mdev_ioctl,

	.request		= vfio_ccw_mdev_request,

};



int vfio_ccw_mdev_reg(struct subchannel *sch)

drivers/s390/cio/vfio_ccw_private.h

+4 −0
Original line number Diff line number Diff line
@@ -84,7 +84,10 @@ struct vfio_ccw_crw { 
 * @irb: irb info received from interrupt

 * @scsw: scsw info

 * @io_trigger: eventfd ctx for signaling userspace I/O results

 * @crw_trigger: eventfd ctx for signaling userspace CRW information

 * @req_trigger: eventfd ctx for signaling userspace to return device

 * @io_work: work for deferral process of I/O handling

 * @crw_work: work for deferral process of CRW handling

 */

struct vfio_ccw_private {

	struct subchannel	*sch;
@@ -108,6 +111,7 @@ struct vfio_ccw_private { 


	struct eventfd_ctx	*io_trigger;

	struct eventfd_ctx	*crw_trigger;

	struct eventfd_ctx	*req_trigger;

	struct work_struct	io_work;

	struct work_struct	crw_work;

} __aligned(8);

include/uapi/linux/vfio.h

+1 −0
Original line number Diff line number Diff line
@@ -820,6 +820,7 @@ enum { 
enum {

	VFIO_CCW_IO_IRQ_INDEX,

	VFIO_CCW_CRW_IRQ_INDEX,

	VFIO_CCW_REQ_IRQ_INDEX,

	VFIO_CCW_NUM_IRQS

};

CRA Git | Maintained and supported by SUSTech CRA and CCSE