user/sven/linux.git/include/linux/mdev.h, branch v5.13.13

vfio/mdev: Correct the function signatures for the mdev_type_attributes

2021-04-12T16:36:00Z

The driver core standard is to pass in the properly typed object, the properly typed attribute and the buffer data. It stems from the root kobject method: ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr,..) Each subclass of kobject should provide their own function with the same signature but more specific types, eg struct device uses: ssize_t (*show)(struct device *dev, struct device_attribute *attr,..) In this case the existing signature is: ssize_t (*show)(struct kobject *kobj, struct device *dev,..) Where kobj is a 'struct mdev_type *' and dev is 'mdev_type->parent->dev'. Change the mdev_type related sysfs attribute functions to: ssize_t (*show)(struct mdev_type *mtype, struct mdev_type_attribute *attr,..) In order to restore type safety and match the driver core standard There are no current users of 'attr', but if it is ever needed it would be hard to add in retroactively, so do it now. Reviewed-by: Kevin Tian Reviewed-by: Cornelia Huck Reviewed-by: Christoph Hellwig Signed-off-by: Jason Gunthorpe Message-Id: <18-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson

vfio/mdev: Remove kobj from mdev_parent_ops->create()

2021-04-12T16:36:00Z

The kobj here is a type-erased version of mdev_type, which is already stored in the struct mdev_device being passed in. It was only ever used to compute the type_group_id, which is now extracted directly from the mdev. Reviewed-by: Kevin Tian Reviewed-by: Cornelia Huck Reviewed-by: Christoph Hellwig Signed-off-by: Jason Gunthorpe Message-Id: <17-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson

vfio/mdev: Add mdev/mtype_get_type_group_id()

2021-04-07T21:39:18Z

This returns the index in the supported_type_groups array that is associated with the mdev_type attached to the struct mdev_device or its containing struct kobject. Each mdev_device can be spawned from exactly one mdev_type, which in turn originates from exactly one supported_type_group. Drivers are using weird string calculations to try and get back to this index, providing a direct access to the index removes a bunch of wonky driver code. mdev_type->group can be deleted as the group is obtained using the type_group_id. Reviewed-by: Christoph Hellwig Reviewed-by: Kevin Tian Reviewed-by: Cornelia Huck Signed-off-by: Jason Gunthorpe Message-Id: <11-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson

vfio/mdev: Remove duplicate storage of parent in mdev_device

2021-04-07T21:39:18Z

mdev_device->type->parent is the same thing. The struct mdev_device was relying on the kref on the mdev_parent to also indirectly hold a kref on the mdev_type pointer. Now that the type holds a kref on the parent we can directly kref the mdev_type and remove this implicit relationship. Reviewed-by: Christoph Hellwig Reviewed-by: Cornelia Huck Signed-off-by: Jason Gunthorpe Message-Id: <10-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson

vfio/mdev: Use struct mdev_type in struct mdev_device

2021-04-07T21:39:17Z

The kobj pointer in mdev_device is actually pointing at a struct mdev_type. Use the proper type so things are understandable. There are a number of places that are confused and passing both the mdev and the mtype as function arguments, fix these to derive the mtype directly from the mdev to remove the redundancy. Reviewed-by: Christoph Hellwig Reviewed-by: Kevin Tian Reviewed-by: Cornelia Huck Signed-off-by: Jason Gunthorpe Message-Id: <5-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson

vfio/mdev: Simplify driver registration

2021-04-07T21:39:16Z

This is only done once, we don't need to generate code to initialize a structure stored in the ELF .data segment. Fill in the three required .driver members directly instead of copying data into them during mdev_register_driver(). Further the to_mdev_driver() function doesn't belong in a public header, just inline it into the two places that need it. Finally, we can now clearly see that 'drv' derived from dev->driver cannot be NULL, firstly because the driver core forbids it, and secondly because NULL won't pass through the container_of(). Remove the dead code. Reviewed-by: Christoph Hellwig Reviewed-by: Kevin Tian Reviewed-by: Cornelia Huck Signed-off-by: Jason Gunthorpe Message-Id: <4-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson

vfio/mdev: Add missing typesafety around mdev_device

2021-04-07T21:39:16Z

The mdev API should accept and pass a 'struct mdev_device *' in all places, not pass a 'struct device *' and cast it internally with to_mdev_device(). Particularly in its struct mdev_driver functions, the whole point of a bus's struct device_driver wrapper is to provide type safety compared to the default struct device_driver. Further, the driver core standard is for bus drivers to expose their device structure in their public headers that can be used with container_of() inlines and '&foo->dev' to go between the class levels, and '&foo->dev' to be used with dev_err/etc driver core helper functions. Move 'struct mdev_device' to mdev.h Once done this allows moving some one instruction exported functions to static inlines, which in turns allows removing one of the two grotesque symbol_get()'s related to mdev in the core code. Reviewed-by: Kevin Tian Reviewed-by: Cornelia Huck Signed-off-by: Jason Gunthorpe Reviewed-by: Christoph Hellwig Message-Id: <3-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson

include/linux: remove repeated words

2021-02-26T17:41:03Z

Drop the doubled word "for" in a comment. {firewire-cdev.h} Drop the doubled word "in" in a comment. {input.h} Drop the doubled word "a" in a comment. {mdev.h} Drop the doubled word "the" in a comment. {ptrace.h} Link: https://lkml.kernel.org/r/20210126232444.22861-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap Cc: Stefan Richter Cc: Dmitry Torokhov Cc: Kirti Wankhede Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

vfio-mdev: Wire in a request handler for mdev parent

2020-12-03T23:21:07Z

While performing some destructive tests with vfio-ccw, where the paths to a device are forcible removed and thus the device itself is unreachable, it is rather easy to end up in an endless loop in vfio_del_group_dev() due to the lack of a request callback for the associated device. In this example, one MDEV (77c) is used by a guest, while another (77b) is not. The symptom is that the iommu is detached from the mdev for 77b, but not 77c, until that guest is shutdown: [ 238.794867] vfio_ccw 0.0.077b: MDEV: Unregistering [ 238.794996] vfio_mdev 11f2d2bc-4083-431d-a023-eff72715c4f0: Removing from iommu group 2 [ 238.795001] vfio_mdev 11f2d2bc-4083-431d-a023-eff72715c4f0: MDEV: detaching iommu [ 238.795036] vfio_ccw 0.0.077c: MDEV: Unregistering ...silence... Let's wire in the request call back to the mdev device, so that a device being physically removed from the host can be (gracefully?) handled by the parent device at the time the device is removed. Add a message when registering the device if a driver doesn't provide this callback, so a clue is given that this same loop may be encountered in a similar situation, and a message when this occurs instead of the awkward silence noted above. Signed-off-by: Eric Farman Reviewed-by: Cornelia Huck Signed-off-by: Alex Williamson

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55Z

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman