This documentation is modified from cifs/cifsroot.rst.

Signed-off-by: Changbin Du <changbin.du@gmail.com>

Later we will add another documentation for v9fs.

Signed-off-by: Changbin Du <changbin.du@gmail.com>

This introduces a new kernel command-line option called 'v9fsroot='
which will tell the kernel to mount the root file system by
utilizing the 9p protocol.

This allows us to mount host folder as rootfs for guest linux in qemu.
Bellow is an example which mounts v9fs with tag 'r' as rootfs in qemu
guest via virtio transport.

  $ qemu-system-x86_64 -enable-kvm -cpu host -m 1024 \
      -virtfs local,path=$rootfs_dir,mount_tag=r,security_model=passthrough,id=r \
      -kernel /path/to/linux/arch/x86/boot/bzImage -nographic \
      -append "root=/dev/v9fs v9fsroot=r,trans=virtio rw console=ttyS0 3"

Signed-off-by: Changbin Du <changbin.du@gmail.com>

Change the file extension and add the rst constructs to integrate this
doc to the documentation infrastructure and take advantage of rst
features.

Signed-off-by: Igor Matheus Andrade Torrente <igormtorrente@gmail.com>
Link: https://lore.kernel.org/r/20210531130515.10309-1-igormtorrente@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Fix typo in the documentation, changed from 'comatible' to
'compatible.

Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Link: https://lore.kernel.org/r/20210531134235.720351-1-iwamatsu@nigauri.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Update the description of the device stat files to include the proper
number of fields.

Signed-off-by: Gao Mingfei <g199209@gmail.com>
Link: https://lore.kernel.org/r/20210601085145.3273-1-g199209@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Replace example code's use of strncpy() with strscpy() functions. Using
strncpy() is considered deprecated:
https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Link: https://lore.kernel.org/r/20210602202914.4079123-1-keescook@chromium.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

…g directories

With multiple git working directories, '.git' may also be a text file
linking to the actual git tree instead of a directory.

Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Tested-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/20210603012806.331132-1-robh@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add new zh translations
* zh_CN/dev-tools/kasan.rst
and link it to zh_CN/dev-tools/index.rst

Reviewed-by: Fangrui Song <maskray@google.com>
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Reviewed-by: Alex Shi <alexs@kernel.org>
Link: https://lore.kernel.org/r/20210603141127.101689-1-wanjiabing@vivo.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add translation zh_CN/admin-guide/lockup-watchdogs.rst and link it to
zh_CN/admin-guide/index.rst while clean its todo entry.

Reviewed-by: Yanteng Si <siyanteng@loongson.cn>
Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn>
Link: https://lore.kernel.org/r/20210603145227.30956-1-liuhailongg6@163.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Translate Documentation/core-api/cachetlb.rst into Chinese.

Reviewed-by: Wu XiangCheng <bobwxc@email.cn>
Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Alex Shi <alexs@kernel.org>
Link: https://lore.kernel.org/r/20210604090655.1971227-1-siyanteng@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Fix the usage of "a/the" and improve the readability.

Signed-off-by: Haocheng Xie <xiehaocheng.cn@gmail.com>
Link: https://lore.kernel.org/r/20210531083905.25763-1-xiehaocheng.cn@gmail.com
[jc: tweaked wording slightly]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Setting a reasonable width to \tymin prevents column squeezing
by tabulary.
Width of 20em works well in almost all the tables still in the
ascii-art format.

Excerpt from tabulary package documentation at [1]:

    To stop very narrow columns being too 'squeezed' by this process
    any columns that are narrower than \tymin are set to their natural
    width.

[1]: https://mirrors.ctan.org/macros/latex/contrib/tabulary/tabulary.pdf

Note: Sphinx has its own default value of \tymin set in
sphinxlatextables.sty (Sphinx 4.0.2) and sphinxmulticell.sty
(Sphinx 2.4.4) as follows:

    \setlength{\tymin}{3\fontcharwd\font`0 }

, which is not sufficient for kernel-doc.

Tested against Sphinx versions 2.4.4 and 4.0.2.

Signed-off-by: Akira Yokosawa <akiyks@gmail.com>
Link: https://lore.kernel.org/r/277d68fa-c96a-0ccb-6ce0-4d314851d9fe@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Translate Documentation/core-api/padata.rst into Chinese.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Wu XiangCheng <bobwxc@email.cn>
Link: https://lore.kernel.org/r/20210531124105.946859-1-siyanteng@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Translates Documentation/core-api/symbol-namespaces.rst into Chinese.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Wu XiangCheng <bobwxc@email.cn>
Link: https://lore.kernel.org/r/20210527064347.3936694-1-siyanteng@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The pip packages are only needed when the distro-provided
Sphinx version is not good enough.

Don't recommend installing it if not needed.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/04ce53b77b37f1e495c3abc39c2d3dc407895dc0.1621949137.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The sphinx-pre-install supports installing sphinx via a virtual
environment using pip/pypi or directly from the distribution's
package, when --no-virtualenv is used.

However, even when --no-virtualenv, the current logic is
still recomending to install a virtual env, due to a regression.

It turns that the logic there is complex, as it depends on
several different conditions.

Split the code which recommends Sphinx on two separate
functions, in order to clean up the code.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/9dedaec201803017b7a7dc24a074f3a4f040b72a.1621949137.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Two new commits were added to the original document:

commit ddba350
commit 20bc8c1

translate them into Chinese.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Wu XiangCheng <bobwxc@email.cn>
Link: https://lore.kernel.org/r/20210524022308.1216098-1-siyanteng@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Translate Documentation/core-api/local_ops.rst into Chinese.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Wu XiangCheng <bobwxc@email.cn>
Link: https://lore.kernel.org/r/11da5738679fbab9e875f434745d16db1f167f90.1621823299.git.siyanteng@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Translate Documentation/core-api/refcount-vs-atomic.rst into Chinese.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Wu XiangCheng <bobwxc@email.cn>
Link: https://lore.kernel.org/r/cbdd1d8b23b8ce6dff0a98a0d89b78673365aa28.1621823299.git.siyanteng@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

…chitectures

risc-v and arm64 support numa=off by common arch_numa_init()
in drivers/base/arch_numa.c. x86, ppc, mips, sparc support it
by arch-level early_param.
numa=off is widely used in linux distributions. it is better
to document it.

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Link: https://lore.kernel.org/r/20210524051715.13604-1-song.bao.hua@hisilicon.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The description of those vars produce this warning:
  Documentation/ABI/testing/sysfs-bus-iio:799: WARNING: Inline emphasis start-string without end-string.

Due to an asterisk, which is the markup for emphasis. One possible
fix would be to use ``*_timeout`` to avoid it, but looking at
the descriptions of other fields in this file, a common pattern
is to refer to "these" when talking about the API calls that
are described.

So, change the text in order to preserve the meaning while
avoiding the need of using an asterisk there.

Reported-by: Jonathan Corbet <corbet@lwn.net>
Reported-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/dbf0d94f85217f103d77dc8389c8db272f5702d2.1621944866.git.mchehab+huawei@kernel.org
[jc fixed specifiy->specify]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Descrption -> Description

This causes some errors when parsed via scripts/get_abi.pl.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/fa90a2deebac80da42b1ad4cf570c4ace436577d.1621944866.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Activating xeCJK in English and Italian-translation documents
results in sub-optimal typesetting with wide-looking apostrophes
and quotation marks.

The xeCJK package provides macros for enabling and disabling its
effect in the middle of a document, namely \makexeCJKactive and
\makexeCJKinactive.

So the goal of this change is to activate xeCJK in the relevant
chapters in translations.

To do this:

    o Define custom macros in the preamble depending on the
      availability of the "Noto Sans CJK" font so that those
      macros can be used regardless of the use of xeCJK package.

    o Patch \sphinxtableofcontents so that xeCJK is inactivated
      after table of contents.

    o Embed those custom macros in each language's index.rst file
      as a ".. raw:: latex" construct.

Note: A CJK chapter needs \kerneldocCJKon in front of its chapter
heading, while a non-CJK chapter should have \kerneldocCJKoff
below its chapter heading.

This is to make sure the CJK font is available to CJK chapter's
heading and ending page's footer.

Tested against Sphinx versions 2.4.4 and 4.0.2.

Signed-off-by: Akira Yokosawa <akiyks@gmail.com>
Tested-by: Wu XiangCheng <bobwxc@email.cn>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/lkml/2061da0a-6ab1-35f3-99c1-dbc415444f37@gmail.com
Link: https://lore.kernel.org/r/83208ddc-5de9-b283-3fd6-92c635348ca0@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

While include/linux/bitops.h brings in the BIT() macro, it was moved to
include/linux/bits.h in commit 8bd9cb5 ("locking/atomics, asm-generic:
Move some macros from <linux/bitops.h> to a new <linux/bits.h> file").

Since that commit BIT() has moved again into include/vdso/bits.h via
commit 3945ff3 ("linux/bits.h: Extract common header for vDSO").

I think the move to the vDSO header can be considered an implementation
detail, so for now update the checkpatch documentation to recommend use
of include/linux/bits.h.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Acked-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20210520093949.511471-1-andrew@aj.id.au
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

It is 'driver' to complete the request. Also remove a redundant space.

Signed-off-by: Yue Hu <huyue2@yulong.com>
Link: https://lore.kernel.org/r/20210520074225.1989-1-zbestahu@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This patch translates Documentation/parisc/registers.rst into Chinese.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Wu XiangCheng <bobwxc@email.cn>
Link: https://lore.kernel.org/r/b8375b5cd2c5163691691fe4757511ce984f3b83.1620805100.git.siyanteng@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This patch translates Documentation/parisc/debugging.rst into Chinese.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Link: https://lore.kernel.org/r/32661b39374f012442b760444ef149afcc0d22af.1620805100.git.siyanteng@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This patch translates Documentation/parisc/index.rst into Chinese.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Wu XiangCheng <bobwxc@email.cn>
Link: https://lore.kernel.org/r/c13ce34b11a65e1f18c4e37566509ead82f2c15f.1620805100.git.siyanteng@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

- Document a couple of more checkpatch message types.
- Add a blank line before all `See:` lines to improve the
  rst output.
- Create a new subsection `Permissions` and move a few types
  to it.

Signed-off-by: Dwaipayan Ray <dwaipayanray1@gmail.com>
Acked-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/r/20210515132348.19082-1-dwaipayanray1@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Replace /* fall through */ comment with fallthrough, make
it align with original process/coding-style.rst

Signed-off-by: Wei Ming Chen <jj251510319013@gmail.com>
Link: https://lore.kernel.org/r/20210515155142.2490-1-jj251510319013@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

It should use post_handler instead of pre_handler in handler_post().

As Joe Perches suggested, it would be better to use pr_fmt and remove
all the embedded pre/post/fault strings. This would change the style of
the output through.

Fixes: e16c5dd ("samples/kprobes: Add s390 case in kprobe example module")
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Marc Koderer <marc@koderer.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/1621218083-23519-3-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Fix a defective format in handler_fault() ending with an 'n' that
should be '\n'.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/1621218083-23519-2-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

As reported by scripts/get_abi.pl:

	Warning: /sys/class/leds/<led>/repeat is defined 2 times:  Documentation/ABI/testing/sysfs-class-led-driver-el15203000:0  Documentation/ABI/testing/sysfs-class-led-trigger-pattern:28

The definition for the EL15203000 is just a special case of
the sysfs led class. So, drop it and mentions the possible
exception at the class definition.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/394580bd2e007ffb640f97212973a772ed8f0409.1621413933.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

./scripts/get_abi.pl is warning about duplicated symbol
definition:

	Warning: /sys/class/backlight/<backlight>/l1_daylight_max is defined 2 times:  ./Documentation/ABI/testing/sysfs-class-backlight-driver-adp8870:4  ./Documentation/ABI/testing/sysfs-class-backlight-adp8860:12

What happens is that 3 drivers use the same pattern to report
max and dim setting for different ambient light zones.

It should be noticed that the adp8870 doc was missing an
entry for l1_daylight_dim, which was fixed on this patch.

While the ambient light zone is device-specific, the sysfs
definition is actually common. So, unify them at:

	Documentation/ABI/testing/sysfs-class-backlight

and use as the contact point, the e-mail reported by
get_maintainers.pl for the subsystem.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/c13c6ebd03cd04a0d15d89018f8d529918fc0a73.1621413933.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>