motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-03 15:53:54 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

vfio/pci: Make vfio cdev pre-openable by passing a file handle

Browse source 
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>
This commit is contained in:
Zhenzhong Duan 2023-11-21 16:44:10 +08:00 • committed by Cédric Le Goater
parent ee42b261b0
commit da3e04b26f
4 changed files with 71 additions and 16 deletions
Download patch file Download diff file Expand all files Collapse all files

4
include/hw/vfio/vfio-common.h
View file

@ -251,4 +251,8 @@ int vfio_devices_query_dirty_bitmap(VFIOContainerBase *bcontainer,
hwaddr size);
int vfio_get_dirty_bitmap(VFIOContainerBase *bcontainer, uint64_t iova,
uint64_t size, ram_addr_t ram_addr);
/* Returns 0 on success, or a negative errno. */
int vfio_device_get_name(VFIODevice *vbasedev, Error **errp);
void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp);
#endif /* HW_VFIO_VFIO_COMMON_H */