[RFC PATCH v1 08/38] iommufd/tsm: Add tsm_op iommufd ioctls

Aneesh Kumar K.V (Arm)
2025-07-28T13:53:24Z

Add operations bind and unbind used to bind a TDI to the secure guest.

Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
---
drivers/iommu/iommufd/iommufd_private.h | 1 +
drivers/iommu/iommufd/main.c | 3 ++
drivers/iommu/iommufd/viommu.c | 50 +++++++++++++++++++++++++
drivers/vfio/pci/vfio_pci_core.c | 10 +++++
include/uapi/linux/iommufd.h | 18 +++++++++
5 files changed, 82 insertions(+)

diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index fce68714c80f..e08186f1d102 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -697,6 +697,7 @@ void iommufd_vdevice_destroy(struct iommufd_object *obj);
void iommufd_vdevice_abort(struct iommufd_object *obj);
int iommufd_hw_queue_alloc_ioctl(struct iommufd_ucmd *ucmd);
void iommufd_hw_queue_destroy(struct iommufd_object *obj);
+int iommufd_vdevice_tsm_op_ioctl(struct iommufd_ucmd *ucmd);

static inline struct iommufd_vdevice *
iommufd_get_vdevice(struct iommufd_ctx *ictx, u32 id)
diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c
index 89830da8b418..4f2a1995bd1f 100644
--- a/drivers/iommu/iommufd/main.c
+++ b/drivers/iommu/iommufd/main.c
@@ -410,6 +410,7 @@ union ucmd_buffer {
struct iommu_veventq_alloc veventq;
struct iommu_vfio_ioas vfio_ioas;
struct iommu_viommu_alloc viommu;
+ struct iommu_vdevice_tsm_op tsm_op;
#ifdef CONFIG_IOMMUFD_TEST
struct iommu_test_cmd test;
#endif
@@ -471,6 +472,8 @@ static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = {
__reserved),
IOCTL_OP(IOMMU_VIOMMU_ALLOC, iommufd_viommu_alloc_ioctl,
struct iommu_viommu_alloc, out_viommu_id),
+ IOCTL_OP(IOMMU_VDEVICE_TSM_OP, iommufd_vdevice_tsm_op_ioctl,
+ struct iommu_vdevice_tsm_op, vdevice_id),
#ifdef CONFIG_IOMMUFD_TEST
IOCTL_OP(IOMMU_TEST_CMD, iommufd_test, struct iommu_test_cmd, last),
#endif
diff --git a/drivers/iommu/iommufd/viommu.c b/drivers/iommu/iommufd/viommu.c
index 59f1e1176f7f..c934312e5397 100644
--- a/drivers/iommu/iommufd/viommu.c
+++ b/drivers/iommu/iommufd/viommu.c
@@ -162,6 +162,9 @@ void iommufd_vdevice_abort(struct iommufd_object *obj)

lockdep_assert_held(&idev->igroup->lock);

+#ifdef CONFIG_TSM
+ tsm_unbind(idev->dev);
+#endif
if (vdev->destroy)
vdev->destroy(vdev);
/* xa_cmpxchg is okay to fail if alloc failed xa_cmpxchg previously */
@@ -471,3 +474,50 @@ int iommufd_hw_queue_alloc_ioctl(struct iommufd_ucmd *ucmd)
iommufd_put_object(ucmd->ictx, &viommu->obj);
return rc;
}
+
+#ifdef CONFIG_TSM
+int iommufd_vdevice_tsm_op_ioctl(struct iommufd_ucmd *ucmd)
+{
+ struct iommu_vdevice_tsm_op *cmd = ucmd->cmd;
+ struct iommufd_vdevice *vdev;
+ struct kvm *kvm;
+ int rc = -ENODEV;
+
+ if (cmd->flags)
+ return -EOPNOTSUPP;
+
+ vdev = container_of(iommufd_get_object(ucmd->ictx, cmd->vdevice_id,
+ IOMMUFD_OBJ_VDEVICE),
+ struct iommufd_vdevice, obj);
+ if (IS_ERR(vdev))
+ return PTR_ERR(vdev);
+
+ kvm = vdev->viommu->kvm_filp->private_data;
+ if (kvm) {
+ /*
+ * tsm layer will make take care of parallel calls to tsm_bind/unbind
+ */
+ if (cmd->op == IOMMU_VDEICE_TSM_BIND)
+ rc = tsm_bind(vdev->idev->dev, kvm, vdev->virt_id);
+ else if (cmd->op == IOMMU_VDEICE_TSM_UNBIND)
+ rc = tsm_unbind(vdev->idev->dev);
+
+ if (rc) {
+ rc = -ENODEV;
+ goto out_put_vdev;
+ }
+ } else {
+ goto out_put_vdev;
+ }
+ rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
+
+out_put_vdev:
+ iommufd_put_object(ucmd->ictx, &vdev->obj);
+ return rc;
+}
+#else /* !CONFIG_TSM */
+int iommufd_vdevice_tsm_op_ioctl(struct iommufd_ucmd *ucmd)
+{
+ return -ENODEV;
+}
+#endif
diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
index bee3cf3226e9..afdb39c6aefd 100644
--- a/drivers/vfio/pci/vfio_pci_core.c
+++ b/drivers/vfio/pci/vfio_pci_core.c
@@ -694,6 +694,16 @@ void vfio_pci_core_close_device(struct vfio_device *core_vdev)
#if IS_ENABLED(CONFIG_EEH)
eeh_dev_release(vdev->pdev);
#endif
+
+#if 0
+ /*
+ * destroy vdevice which involves tsm unbind before we disable pci disable
+ * A MSE/BME clear will transition the device to error state.
+ */
+ if (core_vdev->iommufd_device)
+ iommufd_device_tombstone_vdevice(core_vdev->iommufd_device);
+#endif
+
vfio_pci_core_disable(vdev);

mutex_lock(&vdev->igate);
diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index 9014c61a97d4..8b1fbf1ef25c 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -57,6 +57,7 @@ enum {
IOMMUFD_CMD_IOAS_CHANGE_PROCESS = 0x92,
IOMMUFD_CMD_VEVENTQ_ALLOC = 0x93,
IOMMUFD_CMD_HW_QUEUE_ALLOC = 0x94,
+ IOMMUFD_CMD_VDEVICE_TSM_OP = 0x95,
};

/**
@@ -1127,6 +1128,23 @@ enum iommu_veventq_flag {
IOMMU_VEVENTQ_FLAG_LOST_EVENTS = (1U << 0),
};

+/**
+ * struct iommu_vdevice_tsm_OP - ioctl(IOMMU_VDEVICE_TSM_OP)
+ * @size: sizeof(struct iommu_vdevice_tsm_OP)
+ * @op: Either TSM_BIND or TSM_UNBIMD
+ * @flags: Must be 0
+ * @vdevice_id: Object handle for the vDevice. Returned from IOMMU_VDEVICE_ALLOC
+ */
+struct iommu_vdevice_tsm_op {
+ __u32 size;
+ __u32 op;
+ __u32 flags;
+ __u32 vdevice_id;
+};
+#define IOMMU_VDEVICE_TSM_OP _IO(IOMMUFD_TYPE, IOMMUFD_CMD_VDEVICE_TSM_OP)
+#define IOMMU_VDEICE_TSM_BIND 0x1
+#define IOMMU_VDEICE_TSM_UNBIND 0x2
+
/**
* struct iommufd_vevent_header - Virtual Event Header for a vEVENTQ Status
* @flags: Combination of enum iommu_veventq_flag
--
2.43.0