[PATCH v3 8a/8] doc: Split buffer.rst out of api-summary.rst

["Matthew Wilcox (Oracle)" <willy@infradead.org>]

Buffer heads are no longer a generic filesystem API but an optional
filesystem support library.  Make the documentation structure reflect
that, and include the fine documentation kept in buffer_head.h.
We could give a better overview of what buffer heads are all about,
but my enthusiasm for documenting it is limited.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 Documentation/filesystems/api-summary.rst |  3 ---
 Documentation/filesystems/buffer.rst      | 13 +++++++++++++
 Documentation/filesystems/index.rst       |  1 +
 3 files changed, 14 insertions(+), 3 deletions(-)
 create mode 100644 Documentation/filesystems/buffer.rst

diff --git a/Documentation/filesystems/api-summary.rst b/Documentation/filesystems/api-summary.rst
index 98db2ea5fa12..cc5cc7f3fbd8 100644
--- a/Documentation/filesystems/api-summary.rst
+++ b/Documentation/filesystems/api-summary.rst
@@ -56,9 +56,6 @@ Other Functions
 .. kernel-doc:: fs/namei.c
    :export:
 
-.. kernel-doc:: fs/buffer.c
-   :export:
-
 .. kernel-doc:: block/bio.c
    :export:
 
diff --git a/Documentation/filesystems/buffer.rst b/Documentation/filesystems/buffer.rst
new file mode 100644
index 000000000000..b8e42a3bec44
--- /dev/null
+++ b/Documentation/filesystems/buffer.rst
@@ -0,0 +1,13 @@
+Buffer Heads
+============
+
+Linux uses buffer heads to maintain state about individual filesystem blocks.
+Buffer heads are deprecated and new filesystems should use iomap instead.
+
+Functions
+---------
+
+.. kernel-doc:: include/linux/buffer_head.h
+.. kernel-doc:: fs/buffer.c
+   :export:
+
diff --git a/Documentation/filesystems/index.rst b/Documentation/filesystems/index.rst
index 1f9b4c905a6a..8f5c1ee02e2f 100644
--- a/Documentation/filesystems/index.rst
+++ b/Documentation/filesystems/index.rst
@@ -50,6 +50,7 @@ filesystem implementations.
 .. toctree::
    :maxdepth: 2
 
+   buffer
    journalling
    fscrypt
    fsverity
-- 
2.43.0