[PATCH v8 15/18] docs: add documentation for memfd preservation via LUO

[Pasha Tatashin <pasha.tatashin@soleen.com>]

From: Pratyush Yadav <ptyadav@amazon.de>

Add the documentation under the "Preserving file descriptors" section of
LUO's documentation.

Signed-off-by: Pratyush Yadav <ptyadav@amazon.de>
Co-developed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
---
 Documentation/core-api/liveupdate.rst   |  7 +++++++
 Documentation/mm/index.rst              |  1 +
 Documentation/mm/memfd_preservation.rst | 23 +++++++++++++++++++++++
 MAINTAINERS                             |  1 +
 4 files changed, 32 insertions(+)
 create mode 100644 Documentation/mm/memfd_preservation.rst

diff --git a/Documentation/core-api/liveupdate.rst b/Documentation/core-api/liveupdate.rst
index cca1993008d8..7960eb15a81f 100644
--- a/Documentation/core-api/liveupdate.rst
+++ b/Documentation/core-api/liveupdate.rst
@@ -23,6 +23,13 @@ Live Update Orchestrator ABI
 .. kernel-doc:: include/linux/kho/abi/luo.h
    :doc: Live Update Orchestrator ABI
 
+The following types of file descriptors can be preserved
+
+.. toctree::
+   :maxdepth: 1
+
+   ../mm/memfd_preservation
+
 Public API
 ==========
 .. kernel-doc:: include/linux/liveupdate.h
diff --git a/Documentation/mm/index.rst b/Documentation/mm/index.rst
index ba6a8872849b..7aa2a8886908 100644
--- a/Documentation/mm/index.rst
+++ b/Documentation/mm/index.rst
@@ -48,6 +48,7 @@ documentation, or deleted if it has served its purpose.
    hugetlbfs_reserv
    ksm
    memory-model
+   memfd_preservation
    mmu_notifier
    multigen_lru
    numa
diff --git a/Documentation/mm/memfd_preservation.rst b/Documentation/mm/memfd_preservation.rst
new file mode 100644
index 000000000000..66e0fb6d5ef0
--- /dev/null
+++ b/Documentation/mm/memfd_preservation.rst
@@ -0,0 +1,23 @@
+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+==========================
+Memfd Preservation via LUO
+==========================
+
+.. kernel-doc:: mm/memfd_luo.c
+   :doc: Memfd Preservation via LUO
+
+Memfd Preservation ABI
+======================
+
+.. kernel-doc:: include/linux/kho/abi/memfd.h
+   :doc: DOC: memfd Live Update ABI
+
+.. kernel-doc:: include/linux/kho/abi/memfd.h
+   :internal:
+
+See Also
+========
+
+- :doc:`/core-api/liveupdate`
+- :doc:`/core-api/kho/concepts`
diff --git a/MAINTAINERS b/MAINTAINERS
index 425c46bba764..cabbf30d50e1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14473,6 +14473,7 @@ R:	Pratyush Yadav <pratyush@kernel.org>
 L:	linux-kernel@vger.kernel.org
 S:	Maintained
 F:	Documentation/core-api/liveupdate.rst
+F:	Documentation/mm/memfd_preservation.rst
 F:	Documentation/userspace-api/liveupdate.rst
 F:	include/linux/liveupdate.h
 F:	include/linux/liveupdate/
-- 
2.52.0.460.gd25c4c69ec-goog