diff options
Diffstat (limited to 'drivers/iommu/iommufd/viommu.c')
| -rw-r--r-- | drivers/iommu/iommufd/viommu.c | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/drivers/iommu/iommufd/viommu.c b/drivers/iommu/iommufd/viommu.c index 4081deda9b33..fc13cf4737ea 100644 --- a/drivers/iommu/iommufd/viommu.c +++ b/drivers/iommu/iommufd/viommu.c @@ -143,7 +143,7 @@ void iommufd_vdevice_destroy(struct iommufd_object *obj) int iommufd_vdevice_alloc_ioctl(struct iommufd_ucmd *ucmd) { struct iommu_vdevice_alloc *cmd = ucmd->cmd; - struct iommufd_vdevice *vdev, *curr; + struct iommufd_vdevice *vdev; size_t vdev_size = sizeof(*vdev); struct iommufd_viommu *viommu; struct iommufd_device *idev; @@ -189,7 +189,7 @@ int iommufd_vdevice_alloc_ioctl(struct iommufd_ucmd *ucmd) if (WARN_ON_ONCE(viommu->ops->vdevice_size < vdev_size || !viommu->ops->vdevice_init)) { rc = -EOPNOTSUPP; - goto out_put_idev; + goto out_unlock_igroup; } vdev_size = viommu->ops->vdevice_size; } @@ -218,18 +218,28 @@ int iommufd_vdevice_alloc_ioctl(struct iommufd_ucmd *ucmd) */ idev->vdev = vdev; - curr = xa_cmpxchg(&viommu->vdevs, virt_id, NULL, vdev, GFP_KERNEL); - if (curr) { - rc = xa_err(curr) ?: -EEXIST; + /* + * Reserve the slot with a zero entry (reads back as NULL) until the + * vdevice_init() op accepts the vDEVICE. Only the xa_* helpers hide a + * reserved entry, so never use a raw xas_* iterator on this xarray. + */ + rc = xa_insert(&viommu->vdevs, virt_id, NULL, GFP_KERNEL); + if (rc) { + if (rc == -EBUSY) + rc = -EEXIST; goto out_abort; } if (viommu->ops && viommu->ops->vdevice_init) { rc = viommu->ops->vdevice_init(vdev); - if (rc) + if (rc) { + xa_release(&viommu->vdevs, virt_id); goto out_abort; + } } + xa_store(&viommu->vdevs, virt_id, vdev, GFP_KERNEL); + cmd->out_vdevice_id = vdev->obj.id; rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd)); if (rc) |