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| author | Jason Gunthorpe <jgg@nvidia.com> | 2022-11-29 16:31:50 -0400 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@nvidia.com> | 2022-12-02 11:52:03 -0400 |
| commit | 2a3dab19a0a6c1823645764188776f271de1b3cf (patch) | |
| tree | 605950ffb3143873914fd431f165051f8d94e07b /drivers/vfio/container.c | |
| parent | 0d8227b622f3529661ad6a9702a52932e149a30d (diff) | |
| download | lwn-2a3dab19a0a6c1823645764188776f271de1b3cf.tar.gz lwn-2a3dab19a0a6c1823645764188776f271de1b3cf.zip | |
vfio-iommufd: Allow iommufd to be used in place of a container fd
This makes VFIO_GROUP_SET_CONTAINER accept both a vfio container FD and an
iommufd.
In iommufd mode an IOAS will exist after the SET_CONTAINER, but it will
not be attached to any groups.
For VFIO this means that the VFIO_GROUP_GET_STATUS and
VFIO_GROUP_FLAGS_VIABLE works subtly differently. With the container FD
the iommu_group_claim_dma_owner() is done during SET_CONTAINER but for
IOMMUFD this is done during VFIO_GROUP_GET_DEVICE_FD. Meaning that
VFIO_GROUP_FLAGS_VIABLE could be set but GET_DEVICE_FD will fail due to
viability.
As GET_DEVICE_FD can fail for many reasons already this is not expected to
be a meaningful difference.
Reorganize the tests for if the group has an assigned container or iommu
into a vfio_group_has_iommu() function and consolidate all the duplicated
WARN_ON's etc related to this.
Call container functions only if a container is actually present on the
group.
Link: https://lore.kernel.org/r/5-v4-42cd2eb0e3eb+335a-vfio_iommufd_jgg@nvidia.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Diffstat (limited to 'drivers/vfio/container.c')
| -rw-r--r-- | drivers/vfio/container.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/vfio/container.c b/drivers/vfio/container.c index d97747dfb05d..8772dad68085 100644 --- a/drivers/vfio/container.c +++ b/drivers/vfio/container.c @@ -516,8 +516,11 @@ int vfio_group_use_container(struct vfio_group *group) { lockdep_assert_held(&group->group_lock); - if (!group->container || !group->container->iommu_driver || - WARN_ON(!group->container_users)) + /* + * The container fd has been assigned with VFIO_GROUP_SET_CONTAINER but + * VFIO_SET_IOMMU hasn't been done yet. + */ + if (!group->container->iommu_driver) return -EINVAL; if (group->type == VFIO_NO_IOMMU && !capable(CAP_SYS_RAWIO)) |