[PATCH 12/34] docs: filesystems: convert dax.txt to ReST

[Mauro Carvalho Chehab]

- Add a SPDX header;
- Adjust document title;
- Some whitespace fixes and new line breaks;
- Add it to filesystems/index.rst.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
---
 Documentation/admin-guide/ext4.rst             | 2 +-
 Documentation/filesystems/{dax.txt => dax.rst} | 9 +++++++--
 Documentation/filesystems/ext2.rst             | 2 +-
 Documentation/filesystems/index.rst            | 1 +
 4 files changed, 10 insertions(+), 4 deletions(-)
 rename Documentation/filesystems/{dax.txt => dax.rst} (97%)

diff --git a/Documentation/admin-guide/ext4.rst b/Documentation/admin-guide/ext4.rst
index 9443fcef1876..103bcc345bad 100644
--- a/Documentation/admin-guide/ext4.rst
+++ b/Documentation/admin-guide/ext4.rst
@@ -392,7 +392,7 @@ When mounting an ext4 filesystem, the following option are accepted:
 
   dax
         Use direct access (no page cache).  See
-        Documentation/filesystems/dax.txt.  Note that this option is
+        Documentation/filesystems/dax.rst.  Note that this option is
         incompatible with data=journal.
 
 Data Mode
diff --git a/Documentation/filesystems/dax.txt b/Documentation/filesystems/dax.rst
similarity index 97%
rename from Documentation/filesystems/dax.txt
rename to Documentation/filesystems/dax.rst
index 735f3859b19f..5838144f80f0 100644
--- a/Documentation/filesystems/dax.txt
+++ b/Documentation/filesystems/dax.rst
@@ -1,5 +1,8 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=======================
 Direct Access for files
------------------------
+=======================
 
 Motivation
 ----------
@@ -46,6 +49,7 @@ stall the CPU for an extended period, you should also not attempt to
 implement direct_access.
 
 These block devices may be used for inspiration:
+
 - brd: RAM backed block device driver
 - dcssblk: s390 dcss block device driver
 - pmem: NVDIMM persistent memory driver
@@ -55,6 +59,7 @@ Implementation Tips for Filesystem Writers
 ------------------------------------------
 
 Filesystem support consists of
+
 - adding support to mark inodes as being DAX by setting the S_DAX flag in
   i_flags
 - implementing ->read_iter and ->write_iter operations which use dax_iomap_rw()
@@ -127,6 +132,6 @@ by adding optional struct page support for pages under the control of
 the driver (see CONFIG_NVDIMM_PFN in drivers/nvdimm for an example of
 how to do this). In the non struct page cases O_DIRECT reads/writes to
 those memory ranges from a non-DAX file will fail (note that O_DIRECT
-reads/writes _of a DAX file_ do work, it is the memory that is being
+reads/writes _of a DAX ``file_`` do work, it is the memory that is being
 accessed that is key here).  Other things that will not work in the
 non struct page case include RDMA, sendfile() and splice().
diff --git a/Documentation/filesystems/ext2.rst b/Documentation/filesystems/ext2.rst
index d83dbbb162e2..fa416b7a5802 100644
--- a/Documentation/filesystems/ext2.rst
+++ b/Documentation/filesystems/ext2.rst
@@ -24,7 +24,7 @@ check=none, nocheck	(*)	Don't do extra checking of bitmaps on mount
 				(check=normal and check=strict options removed)
 
 dax				Use direct access (no page cache).  See
-				Documentation/filesystems/dax.txt.
+				Documentation/filesystems/dax.rst.
 
 debug				Extra debugging information is sent to the
 				kernel syslog.  Useful for developers.
diff --git a/Documentation/filesystems/index.rst b/Documentation/filesystems/index.rst
index c4f95f76ba6a..8e3ccb4ed483 100644
--- a/Documentation/filesystems/index.rst
+++ b/Documentation/filesystems/index.rst
@@ -24,6 +24,7 @@ algorithms work.
    splice
    locking
    directory-locking
+   dax
 
    automount-support
 
-- 
2.25.2