Commit 39d0099f authored by Tyrel Datwyler's avatar Tyrel Datwyler Committed by Michael Ellerman
Browse files

powerpc/pseries: Add shutdown() to vio_driver and vio_bus 



Currently, neither the vio_bus or vio_driver structures provide support
for a shutdown() routine.

Add support for shutdown() by allowing drivers to provide a
implementation via function pointer in their vio_driver struct and
provide a proper implementation in the driver template for the vio_bus
that calls a vio drivers shutdown() if defined.

In the case that no shutdown() is defined by a vio driver and a kexec is
in progress we implement a big hammer that calls remove() to ensure no
further DMA for the devices is possible.

Signed-off-by: default avatarTyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210402001325.939668-1-tyreld@linux.ibm.com
parent af31fd0c

arch/powerpc/include/asm/vio.h

+1 −0
Original line number Diff line number Diff line
@@ -114,6 +114,7 @@ struct vio_driver { 
	const struct vio_device_id *id_table;

	int (*probe)(struct vio_dev *dev, const struct vio_device_id *id);

	void (*remove)(struct vio_dev *dev);

	void (*shutdown)(struct vio_dev *dev);

	/* A driver must have a get_desired_dma() function to

	 * be loaded in a CMO environment if it uses DMA.

	 */

arch/powerpc/platforms/pseries/vio.c

+16 −0
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ 
#include <linux/mm.h>

#include <linux/dma-map-ops.h>

#include <linux/kobject.h>

#include <linux/kexec.h>



#include <asm/iommu.h>

#include <asm/dma.h>
@@ -1278,6 +1279,20 @@ static int vio_bus_remove(struct device *dev) 
	return 0;

}



static void vio_bus_shutdown(struct device *dev)

{

	struct vio_dev *viodev = to_vio_dev(dev);

	struct vio_driver *viodrv;



	if (dev->driver) {

		viodrv = to_vio_driver(dev->driver);

		if (viodrv->shutdown)

			viodrv->shutdown(viodev);

		else if (kexec_in_progress)

			vio_bus_remove(dev);

	}

}



/**

 * vio_register_driver: - Register a new vio driver

 * @viodrv:	The vio_driver structure to be registered.
@@ -1617,6 +1632,7 @@ struct bus_type vio_bus_type = { 
	.match = vio_bus_match,

	.probe = vio_bus_probe,

	.remove = vio_bus_remove,

	.shutdown = vio_bus_shutdown,

};



/**