[RFC PATCH 01/15] iommu/vt-d: Register with Live Update Orchestrator

[Samiullah Khawaja <skhawaja@google.com>]

Register Intel IOMMU driver with live update orchestrator as subsystem.
Add stub implementation of the prepare, cancel and finish callbacks.

Signed-off-by: Samiullah Khawaja <skhawaja@google.com>
---
 MAINTAINERS                      |  2 ++
 drivers/iommu/intel/Makefile     |  1 +
 drivers/iommu/intel/liveupdate.c | 45 ++++++++++++++++++++++++++++++++
 3 files changed, 48 insertions(+)
 create mode 100644 drivers/iommu/intel/liveupdate.c

diff --git a/MAINTAINERS b/MAINTAINERS
index baeda8a526aa..e038cdd6aa41 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14228,6 +14228,7 @@ F:	tools/testing/selftests/livepatch/
 LIVE UPDATE
 M:	Pasha Tatashin <pasha.tatashin@soleen.com>
 R:	Pratyush Yadav <pratyush@kernel.org>
+R:	Samiullah Khawaja <skhawaja@google.com>
 L:	linux-kernel@vger.kernel.org
 S:	Maintained
 F:	Documentation/ABI/testing/sysfs-kernel-liveupdate
@@ -14235,6 +14236,7 @@ F:	Documentation/admin-guide/liveupdate.rst
 F:	Documentation/core-api/liveupdate.rst
 F:	Documentation/mm/memfd_preservation.rst
 F:	Documentation/userspace-api/liveupdate.rst
+F:	drivers/iommu/intel/liveupdate.c
 F:	include/linux/liveupdate.h
 F:	include/uapi/linux/liveupdate.h
 F:	kernel/liveupdate/
diff --git a/drivers/iommu/intel/Makefile b/drivers/iommu/intel/Makefile
index ada651c4a01b..58922d580c79 100644
--- a/drivers/iommu/intel/Makefile
+++ b/drivers/iommu/intel/Makefile
@@ -6,3 +6,4 @@ obj-$(CONFIG_INTEL_IOMMU_DEBUGFS) += debugfs.o
 obj-$(CONFIG_INTEL_IOMMU_SVM) += svm.o
 obj-$(CONFIG_IRQ_REMAP) += irq_remapping.o
 obj-$(CONFIG_INTEL_IOMMU_PERF_EVENTS) += perfmon.o
+obj-$(CONFIG_LIVEUPDATE) += liveupdate.o
diff --git a/drivers/iommu/intel/liveupdate.c b/drivers/iommu/intel/liveupdate.c
new file mode 100644
index 000000000000..d73d780d7e19
--- /dev/null
+++ b/drivers/iommu/intel/liveupdate.c
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2025, Google LLC
+ * Author: Samiullah Khawaja <skhawaja@google.com>
+ */
+
+#define pr_fmt(fmt)    "iommu: liveupdate: " fmt
+
+#include <linux/liveupdate.h>
+#include <linux/module.h>
+
+static int intel_liveupdate_prepare(struct liveupdate_subsystem *handle, u64 *data)
+{
+	pr_warn("Not implemented\n");
+	return 0;
+}
+
+static void intel_liveupdate_cancel(struct liveupdate_subsystem *handle, u64 data)
+{
+	pr_warn("Not implemented\n");
+}
+
+static void intel_liveupdate_finish(struct liveupdate_subsystem *handle, u64 data)
+{
+	pr_warn("Not implemented\n");
+}
+
+static struct liveupdate_subsystem_ops intel_liveupdate_subsystem_ops = {
+	.prepare = intel_liveupdate_prepare,
+	.finish = intel_liveupdate_finish,
+	.cancel = intel_liveupdate_cancel,
+};
+
+static struct liveupdate_subsystem intel_liveupdate_subsystem = {
+	.name = "intel-iommu",
+	.ops = &intel_liveupdate_subsystem_ops,
+};
+
+static int __init intel_liveupdate_init(void)
+{
+	WARN_ON_ONCE(liveupdate_register_subsystem(&intel_liveupdate_subsystem));
+	return 0;
+}
+
+late_initcall(intel_liveupdate_init);
-- 
2.51.0.536.g15c5d4f767-goog