Commit Graph

7 Commits

Author SHA1 Message Date
Cédric Le Goater
6ba254801f vfio/iommufd: Remove the use of stat() to check file existence
Using stat() before opening a file or a directory can lead to a
time-of-check to time-of-use (TOCTOU) filesystem race, which is
reported by coverity as a Security best practices violations. The
sequence could be replaced by open and fdopendir but it doesn't add
much in this case. Simply use opendir to avoid the race.

Fixes: CID 1531551
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Zhenzhong Duan <Zhenzhong.duan@intel.com>
2024-01-05 21:25:20 +01:00
Cédric Le Goater
ce5f6d49f5 vfio/iommufd: Introduce a VFIOIOMMU iommufd QOM interface
As previously done for the sPAPR and legacy IOMMU backends, convert
the VFIOIOMMUOps struct to a QOM interface. The set of of operations
for this backend can be referenced with a literal typename instead of
a C struct.

Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Tested-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2024-01-05 21:25:20 +01:00
Zhenzhong Duan
4517c33c31 vfio: Make VFIOContainerBase poiner parameter const in VFIOIOMMUOps callbacks
Some of the callbacks in VFIOIOMMUOps pass VFIOContainerBase poiner,
those callbacks only need read access to the sub object of VFIOContainerBase.
So make VFIOContainerBase, VFIOContainer and VFIOIOMMUFDContainer as const
in these callbacks.

Local functions called by those callbacks also need same changes to avoid
build error.

Suggested-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-12-19 19:03:38 +01:00
Zhenzhong Duan
da3e04b26f vfio/pci: Make vfio cdev pre-openable by passing a file handle
This gives management tools like libvirt a chance to open the vfio
cdev with privilege and pass FD to qemu. This way qemu never needs
to have privilege to open a VFIO or iommu cdev node.

Together with the earlier support of pre-opening /dev/iommu device,
now we have full support of passing a vfio device to unprivileged
qemu by management tool. This mode is no more considered for the
legacy backend. So let's remove the "TODO" comment.

Add helper functions vfio_device_set_fd() and vfio_device_get_name()
to set fd and get device name, they will also be used by other vfio
devices.

There is no easy way to check if a device is mdev with FD passing,
so fail the x-balloon-allowed check unconditionally in this case.

There is also no easy way to get BDF as name with FD passing, so
we fake a name by VFIO_FD[fd].

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-12-19 19:03:38 +01:00
Zhenzhong Duan
96d6f85ff0 vfio/iommufd: Enable pci hot reset through iommufd cdev interface
Implement the newly introduced pci_hot_reset callback named
iommufd_cdev_pci_hot_reset to do iommufd specific check and
reset operation.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-12-19 19:03:38 +01:00
Zhenzhong Duan
714e9affa8 vfio/iommufd: Add support for iova_ranges and pgsizes
Some vIOMMU such as virtio-iommu use IOVA ranges from host side to
setup reserved ranges for passthrough device, so that guest will not
use an IOVA range beyond host support.

Use an uAPI of IOMMUFD to get IOVA ranges of host side and pass to
vIOMMU just like the legacy backend, if this fails, fallback to
64bit IOVA range.

Also use out_iova_alignment returned from uAPI as pgsizes instead of
qemu_real_host_page_size() as a fallback.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-12-19 19:03:38 +01:00
Yi Liu
5ee3dc7af7 vfio/iommufd: Implement the iommufd backend
The iommufd backend is implemented based on the new /dev/iommu user API.
This backend obviously depends on CONFIG_IOMMUFD.

So far, the iommufd backend doesn't support dirty page sync yet.

Co-authored-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-12-19 19:03:38 +01:00