Merge branch 'docs-next' of git://git.lwn.net/linux into devel/docs-next

* 'docs-next' of git://git.lwn.net/linux: (64 commits)
  Add .pyc files to .gitignore
  Doc: PM: Fix a typo in intel_powerclamp.txt
  doc-rst: flat-table directive - initial implementation
  Documentation: add meta-documentation for Sphinx and kernel-doc
  Documentation: tiny typo fix in usb/gadget_multi.txt
  Documentation: fix wrong value in md.txt
  bcache: documentation formatting, edited for clarity, stripe alignment notes
  bcache: documentation updates and corrections
  Documentation: add top level 'make help' output for Sphinx
  Documentation/sphinx: drop modindex, we don't have python modules
  Documentation/sphinx: add support for specifying extra export files
  Documentation/sphinx: use a more sensible string split in kernel-doc extension
  Documentation/sphinx: remove unnecessary temporary variable
  kernel-doc: unify all EXPORT_SYMBOL scanning to one place
  kernel-doc: add support for specifying extra files for EXPORT_SYMBOLs
  kernel-doc: abstract filename mapping
  kernel-doc: add missing semi-colons in option parsing
  kernel-doc: do not warn about duplicate default section names
  kernel-doc: remove old debug cruft from dump_section()
  docs: kernel-doc: Add "example" and "note" to the magic section types
  ...

Documentation/.gitignore

+output
+*.pyc

Documentation/DocBook/Makefile

@@ -33,10 +33,6 @@ PDF_METHOD	= $(prefer-db2x)
 PS_METHOD	= $(prefer-db2x)
 
 
-###
-# The targets that may be used.
-PHONY += xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs cleandocs
-
 targets += $(DOCBOOKS)
 BOOKS := $(addprefix $(obj)/,$(DOCBOOKS))
 xmldocs: $(BOOKS)
@@ -63,6 +59,9 @@ installmandocs: mandocs
 		sort -k 2 -k 1 | uniq -f 1 | sed -e 's: :/:' | \
 		xargs install -m 644 -t /usr/local/man/man9/
 
+# no-op for the DocBook toolchain
+epubdocs:
+
 ###
 #External programs used
 KERNELDOCXMLREF = $(srctree)/scripts/kernel-doc-xml-ref
@@ -219,7 +218,7 @@ silent_gen_xml = :
 ###
 # Help targets as used by the top-level makefile
 dochelp:
-	@echo  ' Linux kernel internal documentation in different formats:'
+	@echo  ' Linux kernel internal documentation in different formats (DocBook):'
 	@echo  '  htmldocs        - HTML'
 	@echo  '  pdfdocs         - PDF'
 	@echo  '  psdocs          - Postscript'
@@ -228,7 +227,7 @@ dochelp:
 	@echo  '  installmandocs  - install man pages generated by mandocs'
 	@echo  '  cleandocs       - clean all generated DocBook files'
 	@echo
-	@echo  'make DOCBOOKS="s1.xml s2.xml" [target] Generate only docs s1.xml s2.xml'
+	@echo  '  make DOCBOOKS="s1.xml s2.xml" [target] Generate only docs s1.xml s2.xml'
 	@echo  '  valid values for DOCBOOKS are: $(DOCBOOKS)'
 
 

Documentation/Makefile.sphinx

+# -*- makefile -*-
+# Makefile for Sphinx documentation
+#
+
+# You can set these variables from the command line.
+SPHINXBUILD   = sphinx-build
+SPHINXOPTS    =
+PAPER         =
+BUILDDIR      = $(obj)/output
+
+# User-friendly check for sphinx-build
+HAVE_SPHINX := $(shell if which $(SPHINXBUILD) >/dev/null 2>&1; then echo 1; else echo 0; fi)
+
+ifeq ($(HAVE_SPHINX),0)
+
+.DEFAULT:
+	$(warning The '$(SPHINXBUILD)' command was not found. Make sure you have Sphinx installed and in PATH, or set the SPHINXBUILD make variable to point to the full path of the '$(SPHINXBUILD)' executable.)
+	@echo "  SKIP    Sphinx $@ target."
+
+else # HAVE_SPHINX
+
+# User-friendly check for rst2pdf
+HAVE_RST2PDF := $(shell if python -c "import rst2pdf" >/dev/null 2>&1; then echo 1; else echo 0; fi)
+
+# Internal variables.
+PAPEROPT_a4     = -D latex_paper_size=a4
+PAPEROPT_letter = -D latex_paper_size=letter
+KERNELDOC       = $(srctree)/scripts/kernel-doc
+KERNELDOC_CONF  = -D kerneldoc_srctree=$(srctree) -D kerneldoc_bin=$(KERNELDOC)
+ALLSPHINXOPTS   = -D version=$(KERNELVERSION) -D release=$(KERNELRELEASE) -d $(BUILDDIR)/.doctrees $(KERNELDOC_CONF) $(PAPEROPT_$(PAPER)) -c $(srctree)/$(src) $(SPHINXOPTS) $(srctree)/$(src)
+# the i18n builder cannot share the environment and doctrees with the others
+I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .
+
+quiet_cmd_sphinx = SPHINX  $@
+      cmd_sphinx = $(SPHINXBUILD) -b $2 $(ALLSPHINXOPTS) $(BUILDDIR)/$2
+
+htmldocs:
+	$(call cmd,sphinx,html)
+
+pdfdocs:
+ifeq ($(HAVE_RST2PDF),0)
+	$(warning The Python 'rst2pdf' module was not found. Make sure you have the module installed to produce PDF output.)
+	@echo "  SKIP    Sphinx $@ target."
+else # HAVE_RST2PDF
+	$(call cmd,sphinx,pdf)
+endif # HAVE_RST2PDF
+
+epubdocs:
+	$(call cmd,sphinx,epub)
+
+xmldocs:
+	$(call cmd,sphinx,xml)
+
+# no-ops for the Sphinx toolchain
+sgmldocs:
+psdocs:
+mandocs:
+installmandocs:
+
+cleandocs:
+	$(Q)rm -rf $(BUILDDIR)
+
+dochelp:
+	@echo  ' Linux kernel internal documentation in different formats (Sphinx):'
+	@echo  '  htmldocs        - HTML'
+	@echo  '  pdfdocs         - PDF'
+	@echo  '  epubdocs        - EPUB'
+	@echo  '  xmldocs         - XML'
+	@echo  '  cleandocs       - clean all generated files'
+
+endif # HAVE_SPHINX

Documentation/dmaengine/provider.txt

@@ -323,7 +323,7 @@ supported.
    * device_resume
      - Resumes a transfer on the channel
      - This command should operate synchronously on the channel,
-       pausing right away the work of the given channel
+       resuming right away the work of the given channel
 
    * device_terminate_all
      - Aborts all the pending and ongoing transfers on the channel

Documentation/index.rst

+.. The Linux Kernel documentation master file, created by
+   sphinx-quickstart on Fri Feb 12 13:51:46 2016.
+   You can adapt this file completely to your liking, but it should at least
+   contain the root `toctree` directive.
+
+Welcome to The Linux Kernel's documentation!
+============================================
+
+Nothing for you to see here *yet*. Please move along.
+
+Contents:
+
+.. toctree::
+   :maxdepth: 2
+
+   kernel-documentation
+
+Indices and tables
+==================
+
+* :ref:`genindex`
+* :ref:`search`

Documentation/kernel-parameters.txt

@@ -3992,8 +3992,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 	trace_event=[event-list]
 			[FTRACE] Set and start specified trace events in order
-			to facilitate early boot debugging.
-			See also Documentation/trace/events.txt
+			to facilitate early boot debugging. The event-list is a
+			comma separated list of trace events to enable. See
+			also Documentation/trace/events.txt
 
 	trace_options=[option-list]
 			[FTRACE] Enable or disable tracer options at boot.

Documentation/md.txt

@@ -602,7 +602,7 @@ These currently include
 
   stripe_cache_size  (currently raid5 only)
       number of entries in the stripe cache.  This is writable, but
-      there are upper and lower limits (32768, 16).  Default is 128.
+      there are upper and lower limits (32768, 17).  Default is 256.
   strip_cache_active (currently raid5 only)
       number of active entries in the stripe cache
   preread_bypass_threshold (currently raid5 only)

Documentation/mic/mpssd/mpssd.c

@@ -1538,9 +1538,9 @@ set_cmdline(struct mic_info *mic)
 
 	len = snprintf(buffer, PATH_MAX,
 		"clocksource=tsc highres=off nohz=off ");
-	len += snprintf(buffer + len, PATH_MAX,
+	len += snprintf(buffer + len, PATH_MAX - len,
 		"cpufreq_on;corec6_off;pc3_off;pc6_off ");
-	len += snprintf(buffer + len, PATH_MAX,
+	len += snprintf(buffer + len, PATH_MAX - len,
 		"ifcfg=static;address,172.31.%d.1;netmask,255.255.255.0",
 		mic->id + 1);
 

Documentation/security/self-protection.txt

@@ -183,8 +183,9 @@ provide meaningful defenses.
 ### Canaries, blinding, and other secrets
 
 It should be noted that things like the stack canary discussed earlier
-are technically statistical defenses, since they rely on a (leakable)
-secret value.
+are technically statistical defenses, since they rely on a secret value,
+and such values may become discoverable through an information exposure
+flaw.
 
 Blinding literal values for things like JITs, where the executable
 contents may be partially under the control of userspace, need a similar
@@ -199,8 +200,8 @@ working?) in order to maximize their success.
 Since the location of kernel memory is almost always instrumental in
 mounting a successful attack, making the location non-deterministic
 raises the difficulty of an exploit. (Note that this in turn makes
-the value of leaks higher, since they may be used to discover desired
-memory locations.)
+the value of information exposures higher, since they may be used to
+discover desired memory locations.)
 
 #### Text and module base
 
@@ -222,14 +223,21 @@ become more difficult to locate.
 Much of the kernel's dynamic memory (e.g. kmalloc, vmalloc, etc) ends up
 being relatively deterministic in layout due to the order of early-boot
 initializations. If the base address of these areas is not the same
-between boots, targeting them is frustrated, requiring a leak specific
-to the region.
+between boots, targeting them is frustrated, requiring an information
+exposure specific to the region.
+
+#### Structure layout
+
+By performing a per-build randomization of the layout of sensitive
+structures, attacks must either be tuned to known kernel builds or expose
+enough kernel memory to determine structure layouts before manipulating
+them.
 
 
-## Preventing Leaks
+## Preventing Information Exposures
 
 Since the locations of sensitive structures are the primary target for
-attacks, it is important to defend against leaks of both kernel memory
+attacks, it is important to defend against exposure of both kernel memory
 addresses and kernel memory contents (since they may contain kernel
 addresses or other sensitive things like canary values).
 
@@ -250,8 +258,8 @@ sure structure holes are cleared.
 When releasing memory, it is best to poison the contents (clear stack on
 syscall return, wipe heap memory on a free), to avoid reuse attacks that
 rely on the old contents of memory. This frustrates many uninitialized
-variable attacks, stack info leaks, heap info leaks, and use-after-free
-attacks.
+variable attacks, stack content exposures, heap content exposures, and
+use-after-free attacks.
 
 ### Destination tracking
 

Documentation/sphinx/convert_template.sed

+#
+# Pandoc doesn't grok <function> or <structname>, so convert them
+# ahead of time.
+#
+# Use the following escapes to pass through pandoc:
+#	$bq = "`"
+#	$lt = "<"
+#	$gt = ">"
+#
+s%<function>\([^<(]\+\)()</function>%:c:func:$bq\1()$bq%g
+s%<function>\([^<(]\+\)</function>%:c:func:$bq\1()$bq%g
+s%<structname>struct *\([^<]\+\)</structname>%:c:type:$bqstruct \1 $lt\1$gt$bq%g
+s%struct <structname>\([^<]\+\)</structname>%:c:type:$bqstruct \1 $lt\1$gt$bq%g
+s%<structname>\([^<]\+\)</structname>%:c:type:$bqstruct \1 $lt\1$gt$bq%g
+#
+# Wrap docproc directives in para and code blocks.
+#
+s%^\(!.*\)$%<para><code>DOCPROC: \1</code></para>%

Documentation/sphinx/kernel-doc.py

+# coding=utf-8
+#
+# Copyright © 2016 Intel Corporation
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the "Software"),
+# to deal in the Software without restriction, including without limitation
+# the rights to use, copy, modify, merge, publish, distribute, sublicense,
+# and/or sell copies of the Software, and to permit persons to whom the
+# Software is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice (including the next
+# paragraph) shall be included in all copies or substantial portions of the
+# Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+# IN THE SOFTWARE.
+#
+# Authors:
+#    Jani Nikula <jani.nikula@intel.com>
+#
+# Please make sure this works on both python2 and python3.
+#
+
+import os
+import subprocess
+import sys
+import re
+import glob
+
+from docutils import nodes, statemachine
+from docutils.statemachine import ViewList
+from docutils.parsers.rst import directives
+from sphinx.util.compat import Directive
+
+class KernelDocDirective(Directive):
+    """Extract kernel-doc comments from the specified file"""
+    required_argument = 1
+    optional_arguments = 4
+    option_spec = {
+        'doc': directives.unchanged_required,
+        'functions': directives.unchanged_required,
+        'export': directives.unchanged,
+        'internal': directives.unchanged,
+    }
+    has_content = False
+
+    def run(self):
+        env = self.state.document.settings.env
+        cmd = [env.config.kerneldoc_bin, '-rst', '-enable-lineno']
+
+        filename = env.config.kerneldoc_srctree + '/' + self.arguments[0]
+        export_file_patterns = []
+
+        # Tell sphinx of the dependency
+        env.note_dependency(os.path.abspath(filename))
+
+        tab_width = self.options.get('tab-width', self.state.document.settings.tab_width)
+
+        # FIXME: make this nicer and more robust against errors
+        if 'export' in self.options:
+            cmd += ['-export']
+            export_file_patterns = str(self.options.get('export')).split()
+        elif 'internal' in self.options:
+            cmd += ['-internal']
+            export_file_patterns = str(self.options.get('internal')).split()
+        elif 'doc' in self.options:
+            cmd += ['-function', str(self.options.get('doc'))]
+        elif 'functions' in self.options:
+            for f in str(self.options.get('functions')).split():
+                cmd += ['-function', f]
+
+        for pattern in export_file_patterns:
+            for f in glob.glob(env.config.kerneldoc_srctree + '/' + pattern):
+                env.note_dependency(os.path.abspath(f))
+                cmd += ['-export-file', f]
+
+        cmd += [filename]
+
+        try:
+            env.app.verbose('calling kernel-doc \'%s\'' % (" ".join(cmd)))
+
+            p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, universal_newlines=True)
+            out, err = p.communicate()
+
+            # python2 needs conversion to unicode.
+            # python3 with universal_newlines=True returns strings.
+            if sys.version_info.major < 3:
+                out, err = unicode(out, 'utf-8'), unicode(err, 'utf-8')
+
+            if p.returncode != 0:
+                sys.stderr.write(err)
+
+                env.app.warn('kernel-doc \'%s\' failed with return code %d' % (" ".join(cmd), p.returncode))
+                return [nodes.error(None, nodes.paragraph(text = "kernel-doc missing"))]
+            elif env.config.kerneldoc_verbosity > 0:
+                sys.stderr.write(err)
+
+            lines = statemachine.string2lines(out, tab_width, convert_whitespace=True)
+            result = ViewList()
+
+            lineoffset = 0;
+            line_regex = re.compile("^#define LINENO ([0-9]+)$")
+            for line in lines:
+                match = line_regex.search(line)
+                if match:
+                    # sphinx counts lines from 0
+                    lineoffset = int(match.group(1)) - 1
+                    # we must eat our comments since the upset the markup
+                else:
+                    result.append(line, filename, lineoffset)
+                    lineoffset += 1
+
+            node = nodes.section()
+            node.document = self.state.document
+            self.state.nested_parse(result, self.content_offset, node)
+
+            return node.children
+
+        except Exception as e:
+            env.app.warn('kernel-doc \'%s\' processing failed with: %s' %
+                         (" ".join(cmd), str(e)))
+            return [nodes.error(None, nodes.paragraph(text = "kernel-doc missing"))]
+
+def setup(app):
+    app.add_config_value('kerneldoc_bin', None, 'env')
+    app.add_config_value('kerneldoc_srctree', None, 'env')
+    app.add_config_value('kerneldoc_verbosity', 1, 'env')
+
+    app.add_directive('kernel-doc', KernelDocDirective)

Documentation/sphinx/post_convert.sed

+#
+# Unescape.
+#
+s/$bq/`/g
+s/$lt/</g
+s/$gt/>/g
+#
+# pandoc thinks that both "_" needs to be escaped.  Remove the extra
+# backslashes.
+#
+s/\\_/_/g
+#
+# Unwrap docproc directives.
+#
+s/^``DOCPROC: !E\(.*\)``$/.. kernel-doc:: \1\n   :export:/
+s/^``DOCPROC: !I\(.*\)``$/.. kernel-doc:: \1\n   :internal:/
+s/^``DOCPROC: !F\([^ ]*\) \(.*\)``$/.. kernel-doc:: \1\n   :functions: \2/
+s/^``DOCPROC: !P\([^ ]*\) \(.*\)``$/.. kernel-doc:: \1\n   :doc: \2/
+s/^``DOCPROC: \(!.*\)``$/.. WARNING: DOCPROC directive not supported: \1/
+#
+# Trim trailing whitespace.
+#
+s/[[:space:]]*$//

Documentation/sphinx/tmplcvt

+#!/bin/bash
+#
+# Convert a template file into something like RST
+#
+# fix <function>
+# feed to pandoc
+# fix \_
+# title line?
+#
+
+in=$1
+rst=$2
+tmp=$rst.tmp
+
+cp $in $tmp
+sed --in-place -f convert_template.sed $tmp
+pandoc -s -S -f docbook -t rst -o $rst $tmp
+sed --in-place -f post_convert.sed $rst
+rm $tmp

Documentation/sync_file.txt

@@ -6,8 +6,8 @@
 
 This document serves as a guide for device drivers writers on what the
 sync_file API is, and how drivers can support it. Sync file is the carrier of
-the fences(struct fence) that needs to synchronized between drivers or across
-process boundaries.
+the fences(struct fence) that are needed to synchronize between drivers or
+across process boundaries.
 
 The sync_file API is meant to be used to send and receive fence information
 to/from userspace. It enables userspace to do explicit fencing, where instead
@@ -32,7 +32,7 @@ in-fences and out-fences
 Sync files can go either to or from userspace. When a sync_file is sent from
 the driver to userspace we call the fences it contains 'out-fences'. They are
 related to a buffer that the driver is processing or is going to process, so
-the driver an create out-fence to be able to notify, through fence_signal(),
+the driver creates an out-fence to be able to notify, through fence_signal(),
 when it has finished using (or processing) that buffer. Out-fences are fences
 that the driver creates.
 

Documentation/thermal/intel_powerclamp.txt

@@ -121,7 +121,7 @@ time is considered largely as a non-causal system where its behavior
 cannot be based on the past or current input. Therefore, the
 intel_powerclamp driver attempts to enforce the desired idle time
 instantly as given input (target idle ratio). After injection,
-powerclamp moniors the actual idle for a given time window and adjust
+powerclamp monitors the actual idle for a given time window and adjust
 the next injection accordingly to avoid over/under correction.
 
 When used in a causal control system, such as a temperature control,

Documentation/usb/gadget_multi.txt

@@ -36,7 +36,7 @@ configuration with CDC ECM which should work better under Linux.
 
 ** Windows host drivers
 
-For the gadget two work under Windows two conditions have to be met:
+For the gadget to work under Windows two conditions have to be met:
 
 *** Detecting as composite gadget
 

Makefile

@@ -1364,6 +1364,8 @@ help:
 	@$(MAKE) $(build)=$(package-dir) help
 	@echo  ''
 	@echo  'Documentation targets:'
+	@$(MAKE) -f $(srctree)/Documentation/Makefile.sphinx dochelp
+	@echo  ''
 	@$(MAKE) -f $(srctree)/Documentation/DocBook/Makefile dochelp
 	@echo  ''
 	@echo  'Architecture specific targets ($(SRCARCH)):'
@@ -1412,8 +1414,11 @@ $(help-board-dirs): help-%:
 
 # Documentation targets
 # ---------------------------------------------------------------------------
-%docs: scripts_basic FORCE
+DOC_TARGETS := xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs epubdocs cleandocs
+PHONY += $(DOC_TARGETS)
+$(DOC_TARGETS): scripts_basic FORCE
 	$(Q)$(MAKE) $(build)=scripts build_docproc build_check-lc_ctype
+	$(Q)$(MAKE) $(build)=Documentation -f $(srctree)/Documentation/Makefile.sphinx $@
 	$(Q)$(MAKE) $(build)=Documentation/DocBook $@
 
 else # KBUILD_EXTMOD