Commit 89345d51 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Alex Williamson
Browse files

vfio/mdev: embedd struct mdev_parent in the parent data structure 



Simplify mdev_{un}register_device by requiring the caller to pass in
a structure allocate as part of the parent device structure.  This
removes the need for a list of parents and the separate mdev_parent
refcount as we can simplify rely on the reference to the parent device.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: default avatarTony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Reviewed-by: default avatarKirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: default avatarEric Farman <farman@linux.ibm.com>
Link: https://lore.kernel.org/r/20220923092652.100656-5-hch@lst.de


Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent bdef2b78

Documentation/driver-api/vfio-mediated-device.rst

+6 −6
Original line number Diff line number Diff line
@@ -58,19 +58,19 @@ devices as examples, as these devices are the first devices to use this module:: 
     |  MDEV CORE    |

     |   MODULE      |

     |   mdev.ko     |

     | +-----------+ |  mdev_register_device() +--------------+

     | +-----------+ |  mdev_register_parent() +--------------+

     | |           | +<------------------------+              |

     | |           | |                         |  nvidia.ko   |<-> physical

     | |           | +------------------------>+              |    device

     | |           | |        callbacks        +--------------+

     | | Physical  | |

     | |  device   | |  mdev_register_device() +--------------+

     | |  device   | |  mdev_register_parent() +--------------+

     | | interface | |<------------------------+              |

     | |           | |                         |  i915.ko     |<-> physical

     | |           | +------------------------>+              |    device

     | |           | |        callbacks        +--------------+

     | |           | |

     | |           | |  mdev_register_device() +--------------+

     | |           | |  mdev_register_parent() +--------------+

     | |           | +<------------------------+              |

     | |           | |                         | ccw_device.ko|<-> physical

     | |           | +------------------------>+              |    device
@@ -125,7 +125,7 @@ vfio_device_ops. 
When a driver wants to add the GUID creation sysfs to an existing device it has

probe'd to then it should call::



    int mdev_register_device(struct device *dev,

    int mdev_register_parent(struct mdev_parent *parent, struct device *dev,

			struct mdev_driver *mdev_driver);



This will provide the 'mdev_supported_types/XX/create' files which can then be
@@ -134,7 +134,7 @@ attached to the specified driver. 


When the driver needs to remove itself it calls::



    void mdev_unregister_device(struct device *dev);

    void mdev_unregister_parent(struct mdev_parent *parent);



Which will unbind and destroy all the created mdevs and remove the sysfs files.

Documentation/s390/vfio-ap.rst

+1 −1
Original line number Diff line number Diff line
@@ -297,7 +297,7 @@ of the VFIO AP mediated device driver:: 
   |  MDEV CORE  |

   |   MODULE    |

   |   mdev.ko   |

   | +---------+ | mdev_register_device() +--------------+

   | +---------+ | mdev_register_parent() +--------------+

   | |Physical | +<-----------------------+              |

   | | device  | |                        |  vfio_ap.ko  |<-> matrix

   | |interface| +----------------------->+              |    device

Documentation/s390/vfio-ccw.rst

+1 −1
Original line number Diff line number Diff line
@@ -156,7 +156,7 @@ Below is a high Level block diagram:: 
 |  MDEV CORE  |

 |   MODULE    |

 |   mdev.ko   |

 | +---------+ | mdev_register_device() +--------------+

 | +---------+ | mdev_register_parent() +--------------+

 | |Physical | +<-----------------------+              |

 | | device  | |                        |  vfio_ccw.ko |<-> subchannel

 | |interface| +----------------------->+              |     device

drivers/gpu/drm/i915/gvt/gvt.h

+2 −0
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ 
#include <uapi/linux/pci_regs.h>

#include <linux/kvm_host.h>

#include <linux/vfio.h>

#include <linux/mdev.h>



#include "i915_drv.h"

#include "intel_gvt.h"
@@ -337,6 +338,7 @@ struct intel_gvt { 
	struct intel_gvt_workload_scheduler scheduler;

	struct notifier_block shadow_ctx_notifier_block[I915_NUM_ENGINES];

	DECLARE_HASHTABLE(cmd_table, GVT_CMD_HASH_BITS);

	struct mdev_parent parent;

	struct intel_vgpu_type *types;

	unsigned int num_types;

	struct intel_vgpu *idle_vgpu;

drivers/gpu/drm/i915/gvt/kvmgt.c

+3 −2
Original line number Diff line number Diff line
@@ -1923,7 +1923,7 @@ static void intel_gvt_clean_device(struct drm_i915_private *i915) 
	if (drm_WARN_ON(&i915->drm, !gvt))

		return;



	mdev_unregister_device(i915->drm.dev);

	mdev_unregister_parent(&gvt->parent);

	intel_gvt_cleanup_vgpu_type_groups(gvt);

	intel_gvt_destroy_idle_vgpu(gvt->idle_vgpu);

	intel_gvt_clean_vgpu_types(gvt);
@@ -2028,7 +2028,8 @@ static int intel_gvt_init_device(struct drm_i915_private *i915) 
	if (ret)

		goto out_destroy_idle_vgpu;



	ret = mdev_register_device(i915->drm.dev, &intel_vgpu_mdev_driver);

	ret = mdev_register_parent(&gvt->parent, i915->drm.dev,

				   &intel_vgpu_mdev_driver);

	if (ret)

		goto out_cleanup_vgpu_type_groups;