4 files changed, 116 insertions, 97 deletions
diff --git a/Documentation/doc-guide/docbook.rst b/Documentation/doc-guide/docbook.rst
deleted file mode 100644
index d8bf04308b43..000000000000
--- a/Documentation/doc-guide/docbook.rst
+++ /dev/null
@@ -1,90 +0,0 @@
-DocBook XML [DEPRECATED]
-========================
-
-.. attention::
-
-   This section describes the deprecated DocBook XML toolchain. Please do not
-   create new DocBook XML template files. Please consider converting existing
-   DocBook XML templates files to Sphinx/reStructuredText.
-
-Converting DocBook to Sphinx
-----------------------------
-
-Over time, we expect all of the documents under ``Documentation/DocBook`` to be
-converted to Sphinx and reStructuredText. For most DocBook XML documents, a good
-enough solution is to use the simple ``Documentation/sphinx/tmplcvt`` script,
-which uses ``pandoc`` under the hood. For example::
-
-  $ cd Documentation/sphinx
-  $ ./tmplcvt ../DocBook/in.tmpl ../out.rst
-
-Then edit the resulting rst files to fix any remaining issues, and add the
-document in the ``toctree`` in ``Documentation/index.rst``.
-
-Components of the kernel-doc system
------------------------------------
-
-Many places in the source tree have extractable documentation in the form of
-block comments above functions. The components of this system are:
-
-- ``scripts/kernel-doc``
-
-  This is a perl script that hunts for the block comments and can mark them up
-  directly into reStructuredText, DocBook, man, text, and HTML. (No, not
-  texinfo.)
-
-- ``Documentation/DocBook/*.tmpl``
-
-  These are XML template files, which are normal XML files with special
-  place-holders for where the extracted documentation should go.
-
-- ``scripts/docproc.c``
-
-  This is a program for converting XML template files into XML files. When a
-  file is referenced it is searched for symbols exported (EXPORT_SYMBOL), to be
-  able to distinguish between internal and external functions.
-
-  It invokes kernel-doc, giving it the list of functions that are to be
-  documented.
-
-  Additionally it is used to scan the XML template files to locate all the files
-  referenced herein. This is used to generate dependency information as used by
-  make.
-
-- ``Makefile``
-
-  The targets 'xmldocs', 'psdocs', 'pdfdocs', and 'htmldocs' are used to build
-  DocBook XML files, PostScript files, PDF files, and html files in
-  Documentation/DocBook. The older target 'sgmldocs' is equivalent to 'xmldocs'.
-
-- ``Documentation/DocBook/Makefile``
-
-  This is where C files are associated with SGML templates.
-
-How to use kernel-doc comments in DocBook XML template files
-------------------------------------------------------------
-
-DocBook XML template files (\*.tmpl) are like normal XML files, except that they
-can contain escape sequences where extracted documentation should be inserted.
-
-``!E<filename>`` is replaced by the documentation, in ``<filename>``, for
-functions that are exported using ``EXPORT_SYMBOL``: the function list is
-collected from files listed in ``Documentation/DocBook/Makefile``.
-
-``!I<filename>`` is replaced by the documentation for functions that are **not**
-exported using ``EXPORT_SYMBOL``.
-
-``!D<filename>`` is used to name additional files to search for functions
-exported using ``EXPORT_SYMBOL``.
-
-``!F<filename> <function [functions...]>`` is replaced by the documentation, in
-``<filename>``, for the functions listed.
-
-``!P<filename> <section title>`` is replaced by the contents of the ``DOC:``
-section titled ``<section title>`` from ``<filename>``. Spaces are allowed in
-``<section title>``; do not quote the ``<section title>``.
-
-``!C<filename>`` is replaced by nothing, but makes the tools check that all DOC:
-sections and documented functions, symbols, etc. are used. This makes sense to
-use when you use ``!F`` or ``!P`` only and want to verify that all documentation
-is included.
diff --git a/Documentation/doc-guide/index.rst b/Documentation/doc-guide/index.rst
index 6fff4024606e..a7f95d7d3a63 100644
--- a/Documentation/doc-guide/index.rst
+++ b/Documentation/doc-guide/index.rst
@@ -10,7 +10,6 @@ How to write kernel documentation
    sphinx.rst
    kernel-doc.rst
    parse-headers.rst
-   docbook.rst
 
 .. only::  subproject and html
 
diff --git a/Documentation/doc-guide/kernel-doc.rst b/Documentation/doc-guide/kernel-doc.rst
index b32e4813ff6f..b24854b5d6be 100644
--- a/Documentation/doc-guide/kernel-doc.rst
+++ b/Documentation/doc-guide/kernel-doc.rst
@@ -149,6 +149,16 @@ Domain`_ references.
 ``%CONST``
   Name of a constant. (No cross-referencing, just formatting.)
 
+````literal````
+  A literal block that should be handled as-is. The output will use a
+  ``monospaced font``.
+
+  Useful if you need to use special characters that would otherwise have some
+  meaning either by kernel-doc script of by reStructuredText.
+
+  This is particularly useful if you need to use things like ``%ph`` inside
+  a function description.
+
 ``$ENVVAR``
   Name of an environment variable. (No cross-referencing, just formatting.)
 
diff --git a/Documentation/doc-guide/sphinx.rst b/Documentation/doc-guide/sphinx.rst
index 731334de3efd..a2417633fdd8 100644
--- a/Documentation/doc-guide/sphinx.rst
+++ b/Documentation/doc-guide/sphinx.rst
@@ -15,15 +15,114 @@ are used to describe the functions and types and design of the code. The
 kernel-doc comments have some special structure and formatting, but beyond that
 they are also treated as reStructuredText.
 
-There is also the deprecated DocBook toolchain to generate documentation from
-DocBook XML template files under ``Documentation/DocBook``. The DocBook files
-are to be converted to reStructuredText, and the toolchain is slated to be
-removed.
-
 Finally, there are thousands of plain text documentation files scattered around
 ``Documentation``. Some of these will likely be converted to reStructuredText
 over time, but the bulk of them will remain in plain text.
 
+.. _sphinx_install:
+
+Sphinx Install
+==============
+
+The ReST markups currently used by the Documentation/ files are meant to be
+built with ``Sphinx`` version 1.3 or upper. If you're desiring to build
+PDF outputs, it is recommended to use version 1.4.6 or upper.
+
+There's a script that checks for the Spinx requirements. Please see
+:ref:`sphinx-pre-install` for further details.
+
+Most distributions are shipped with Sphinx, but its toolchain is fragile,
+and it is not uncommon that upgrading it or some other Python packages
+on your machine would cause the documentation build to break.
+
+A way to get rid of that is to use a different version than the one shipped
+on your distributions. In order to do that, it is recommended to install
+Sphinx inside a virtual environment, using ``virtualenv-3``
+or ``virtualenv``, depending on how your distribution packaged Python 3.
+
+.. note::
+
+   #) Sphinx versions below 1.5 don't work properly with Python's
+      docutils version 0.13.1 or upper. So, if you're willing to use
+      those versions, you should run ``pip install 'docutils==0.12'``.
+
+   #) It is recommended to use the RTD theme for html output. Depending
+      on the Sphinx version, it should be installed  in separate,
+      with ``pip install sphinx_rtd_theme``.
+
+   #) Some ReST pages contain math expressions. Due to the way Sphinx work,
+      those expressions are written using LaTeX notation. It needs texlive
+      installed with amdfonts and amsmath in order to evaluate them.
+
+In summary, if you want to install Sphinx version 1.4.9, you should do::
+
+       $ virtualenv sphinx_1.4
+       $ . sphinx_1.4/bin/activate
+       (sphinx_1.4) $ pip install -r Documentation/sphinx/requirements.txt
+
+After running ``. sphinx_1.4/bin/activate``, the prompt will change,
+in order to indicate that you're using the new environment. If you
+open a new shell, you need to rerun this command to enter again at
+the virtual environment before building the documentation.
+
+Image output
+------------
+
+The kernel documentation build system contains an extension that
+handles images on both GraphViz and SVG formats (see
+:ref:`sphinx_kfigure`).
+
+For it to work, you need to install both GraphViz and ImageMagick
+packages. If those packages are not installed, the build system will
+still build the documentation, but won't include any images at the
+output.
+
+PDF and LaTeX builds
+--------------------
+
+Such builds are currently supported only with Sphinx versions 1.4 and upper.
+
+For PDF and LaTeX output, you'll also need ``XeLaTeX`` version 3.14159265.
+
+Depending on the distribution, you may also need to install a series of
+``texlive`` packages that provide the minimal set of functionalities
+required for ``XeLaTeX`` to work.
+
+.. _sphinx-pre-install:
+
+Checking for Sphinx dependencies
+--------------------------------
+
+There's a script that automatically check for Sphinx dependencies. If it can
+recognize your distribution, it will also give a hint about the install
+command line options for your distro::
+
+	$ ./scripts/sphinx-pre-install
+	Checking if the needed tools for Fedora release 26 (Twenty Six) are available
+	Warning: better to also install "texlive-luatex85".
+	You should run:
+
+		sudo dnf install -y texlive-luatex85
+		/usr/bin/virtualenv sphinx_1.4
+		. sphinx_1.4/bin/activate
+		pip install -r Documentation/sphinx/requirements.txt
+
+	Can't build as 1 mandatory dependency is missing at ./scripts/sphinx-pre-install line 468.
+
+By default, it checks all the requirements for both html and PDF, including
+the requirements for images, math expressions and LaTeX build, and assumes
+that a virtual Python environment will be used. The ones needed for html
+builds are assumed to be mandatory; the others to be optional.
+
+It supports two optional parameters:
+
+``--no-pdf``
+	Disable checks for PDF;
+
+``--no-virtualenv``
+	Use OS packaging for Sphinx instead of Python virtual environment.
+
+
 Sphinx Build
 ============
 
@@ -123,7 +222,7 @@ Here are some specific guidelines for the kernel documentation:
 the C domain
 ------------
 
-The `Sphinx C Domain`_ (name c) is suited for documentation of C API. E.g. a
+The **Sphinx C Domain** (name c) is suited for documentation of C API. E.g. a
 function prototype:
 
 .. code-block:: rst
@@ -234,6 +333,7 @@ Rendered as:
 
         - column 3
 
+.. _sphinx_kfigure:
 
 Figures & Images
 ================