Hi,
On 02/06/2023 01:48, Vikram Garhwal wrote:
Remove master device from the IOMMU. This will be helpful when removing the
overlay nodes using dynamic programming during run time.
Signed-off-by: Vikram Garhwal <vikram.garh...@amd.com>
Reviewed-by: Michal Orzel <michal.or...@amd.com>
Acked-by: Jan Beulich <jbeul...@suse.com>
---
xen/drivers/passthrough/device_tree.c | 41 +++++++++++++++++++++++++++
xen/include/xen/iommu.h | 2 ++
2 files changed, 43 insertions(+)
diff --git a/xen/drivers/passthrough/device_tree.c
b/xen/drivers/passthrough/device_tree.c
index 8cc413f867..301a5bcd97 100644
--- a/xen/drivers/passthrough/device_tree.c
+++ b/xen/drivers/passthrough/device_tree.c
@@ -126,6 +126,47 @@ int iommu_release_dt_devices(struct domain *d)
return 0;
}
+int iommu_remove_dt_device(struct dt_device_node *np)
+{
+ const struct iommu_ops *ops = iommu_get_ops();
+ struct device *dev = dt_to_dev(np);
+ int rc;
+
iommu_add_dt_device() checks if the IOMMU is enabled. I think you should
do the same here as well and return 0 if it is disabled.
+ if ( !ops )
+ return -EOPNOTSUPP;
+
+ spin_lock(&dtdevs_lock);
+
+ if ( iommu_dt_device_is_assigned_locked(np) )
+ {
+ rc = -EBUSY;
+ goto fail;
+ }
+
+ /*
+ * The driver which supports generic IOMMU DT bindings must have this
+ * callback implemented.
+ */
It is not clear to me why you want to mandate remove_device when using
the generic IOMMU DT bindings.
But if this is really necessary, then I think the comment should be
placed on top of the callback definition rather than in the caller.
+ if ( !ops->remove_device )
+ {
+ rc = -EOPNOTSUPP;
+ goto fail;
+ }
+
+ /*
+ * Remove master device from the IOMMU if latter is present and available.
+ * The driver is responsible for removing is_protected flag.
+ */
+ rc = ops->remove_device(0, dev);
+
+ if ( !rc )
+ iommu_fwspec_free(dev);
+
+fail:
+ spin_unlock(&dtdevs_lock);
+ return rc;
+}
+
int iommu_add_dt_device(struct dt_device_node *np)
{
const struct iommu_ops *ops = iommu_get_ops();
diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h
index 405db59971..0d7924821b 100644
--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -229,6 +229,8 @@ int iommu_release_dt_devices(struct domain *d);
*/
int iommu_add_dt_device(struct dt_device_node *np);
+int iommu_remove_dt_device(struct dt_device_node *np);
+
int iommu_do_dt_domctl(struct xen_domctl *, struct domain *,
XEN_GUEST_HANDLE_PARAM(xen_domctl_t));
Cheers,
--
Julien Grall
