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author | Jason Gunthorpe <jgg@nvidia.com> | 2021-03-30 18:53:05 +0300 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-08-21 16:16:07 +0300 |
commit | a2fbf4acd28069d4922c33e4b5b0d58fc38073f8 (patch) | |
tree | e1b7f8a75e89364b21232364f8abb487f90fe68c /Documentation/livepatch/callbacks.rst | |
parent | f54fa910e6cb5b771a1c86716c85af730acae4ac (diff) | |
download | linux-a2fbf4acd28069d4922c33e4b5b0d58fc38073f8.tar.xz |
vfio: Split creation of a vfio_device into init and register ops
[ Upstream commit 0bfc6a4ea63c2adac71a824397ef48f28dbc5e47 ]
This makes the struct vfio_device part of the public interface so it
can be used with container_of and so forth, as is typical for a Linux
subystem.
This is the first step to bring some type-safety to the vfio interface by
allowing the replacement of 'void *' and 'struct device *' inputs with a
simple and clear 'struct vfio_device *'
For now the self-allocating vfio_add_group_dev() interface is kept so each
user can be updated as a separate patch.
The expected usage pattern is
driver core probe() function:
my_device = kzalloc(sizeof(*mydevice));
vfio_init_group_dev(&my_device->vdev, dev, ops, mydevice);
/* other driver specific prep */
vfio_register_group_dev(&my_device->vdev);
dev_set_drvdata(dev, my_device);
driver core remove() function:
my_device = dev_get_drvdata(dev);
vfio_unregister_group_dev(&my_device->vdev);
/* other driver specific tear down */
kfree(my_device);
Allowing the driver to be able to use the drvdata and vfio_device to go
to/from its own data.
The pattern also makes it clear that vfio_register_group_dev() must be
last in the sequence, as once it is called the core code can immediately
start calling ops. The init/register gap is provided to allow for the
driver to do setup before ops can be called and thus avoid races.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <3-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'Documentation/livepatch/callbacks.rst')
0 files changed, 0 insertions, 0 deletions