linux-toradex.git/samples/vfio-mdev/mtty.c, branch v5.19-rc3

vfio/mdev: Remove mdev_parent_ops

2022-04-21T11:36:56+00:00

The last useful member in this struct is the supported_type_groups, move
it to the mdev_driver and delete mdev_parent_ops.

Replace it with mdev_driver as an argument to mdev_register_device()

Signed-off-by: Jason Gunthorpe 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Zhi Wang 
Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-33-hch@lst.de
Reviewed-by: Kirti Wankhede 
Reviewed-by: Zhi Wang

vfio/mdev: Remove mdev_parent_ops dev_attr_groups

2022-04-21T11:36:56+00:00

This is only used by one sample to print a fixed string that is pointless.

In general, having a device driver attach sysfs attributes to the parent
is horrific. This should never happen, and always leads to some kind of
liftime bug as it become very difficult for the sysfs attribute to go back
to any data owned by the device driver.

Remove the general mechanism to create this abuse.

Signed-off-by: Jason Gunthorpe 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Zhi Wang 
Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-32-hch@lst.de
Reviewed-by: Kirti Wankhede 
Reviewed-by: Zhi Wang

vfio: simplify iommu group allocation for mediated devices

2021-09-30T18:46:44+00:00

Reuse the logic in vfio_noiommu_group_alloc to allocate a fake
single-device iommu group for mediated devices by factoring out a common
function, and replacing the noiommu boolean field in struct vfio_group
with an enum to distinguish the three different kinds of groups.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Kevin Tian 
Link: https://lore.kernel.org/r/20210924155705.4258-8-hch@lst.de
Signed-off-by: Alex Williamson

vfio/samples: Delete useless open/close

2021-08-11T15:50:11+00:00

The core code no longer requires these ops to be defined, so delete these
empty functions and leave the op as NULL. mtty's functions only log a
pointless message, delete that entirely.

Signed-off-by: Yishai Hadas 
Reviewed-by: Cornelia Huck 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jason Gunthorpe 
Link: https://lore.kernel.org/r/5-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson

vfio: Introduce a vfio_uninit_group_dev() API call

2021-08-11T15:50:10+00:00

This pairs with vfio_init_group_dev() and allows undoing any state that is
stored in the vfio_device unrelated to registration. Add appropriately
placed calls to all the drivers.

The following patch will use this to add pre-registration state for the
device set.

Signed-off-by: Max Gurtovoy 
Reviewed-by: Cornelia Huck 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jason Gunthorpe 
Link: https://lore.kernel.org/r/3-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson

vfio/mtty: Enforce available_instances

2021-06-28T20:09:01+00:00

The sample mtty mdev driver doesn't actually enforce the number of
device instances it claims are available.  Implement this properly.

Link: https://lore.kernel.org/r/162465624894.3338367.12935940647049917981.stgit@omen
Reviewed-by: Jason Gunthorpe 
Reviewed-by: Cornelia Huck 
Reviewed by: Kirti Wankhede 
Signed-off-by: Alex Williamson

vfio/mtty: Delete mdev_devices_list

2021-06-28T14:52:15+00:00

Dan points out that an error case left things on this list. It is also
missing locking in available_instances_show().

Further study shows the list isn't needed at all, just store the total
ports in use in an atomic and delete the whole thing.

Reported-by: Dan Carpenter 
Fixes: 09177ac91921 ("vfio/mtty: Convert to use vfio_register_group_dev()")
Signed-off-by: Jason Gunthorpe 
Link: https://lore.kernel.org/r/0-v1-0bc56b362ca7+62-mtty_used_ports_jgg@nvidia.com
Reviewed-by: Cornelia Huck 
Signed-off-by: Alex Williamson

vfio/mtty: Convert to use vfio_register_group_dev()

2021-06-21T21:29:25+00:00

This is straightforward conversion, the mdev_state is actually serving as
the vfio_device and we can replace all the mdev_get_drvdata()'s and the
wonky dead code with a simple container_of()

Reviewed-by: Christoph Hellwig 
Signed-off-by: Jason Gunthorpe 
Signed-off-by: Christoph Hellwig 
Reviewed-by: Greg Kroah-Hartman 
Reviewed-by: Kirti Wankhede 
Link: https://lore.kernel.org/r/20210617142218.1877096-9-hch@lst.de
Signed-off-by: Alex Williamson

vfio/mdev: Correct the function signatures for the mdev_type_attributes

2021-04-12T16:36:00+00:00

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()

2021-04-12T16:36:00+00:00

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