Commit a02dcdf6 authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab Committed by Jonathan Corbet
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docs: filesystems: convert mandatory-locking.txt to ReST 



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

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/aecd6259fe9f99b2c2b3440eab6a2b989125e00d.1588021877.git.mchehab+huawei@kernel.org


Signed-off-by: default avatarJonathan Corbet <corbet@lwn.net>
parent 63526525

Documentation/filesystems/index.rst

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@@ -29,6 +29,7 @@ algorithms work. 
   fiemap

   files

   locks

   mandatory-locking



   automount-support

Documentation/filesystems/locks.rst

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@@ -58,7 +58,7 @@ fcntl(), with all the problems that implies. 
---------------------------------------



Mandatory locking, as described in

'Documentation/filesystems/mandatory-locking.txt' was prior to this release a

'Documentation/filesystems/mandatory-locking.rst' was prior to this release a

general configuration option that was valid for all mounted filesystems.  This

had a number of inherent dangers, not the least of which was the ability to

freeze an NFS server by asking it to read a file for which a mandatory lock

Documentation/filesystems/mandatory-locking.txt→Documentation/filesystems/mandatory-locking.rst

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.. SPDX-License-Identifier: GPL-2.0



=====================================================

Mandatory File Locking For The Linux Operating System

=====================================================



		Andy Walker <andy@lysaker.kvaerner.no>



			   15 April 1996



		     (Updated September 2007)



0. Why you should avoid mandatory locking
@@ -53,13 +58,15 @@ possible on existing user code. The scheme is based on marking individual files 
as candidates for mandatory locking, and using the existing fcntl()/lockf()

interface for applying locks just as if they were normal, advisory locks.



Note 1: In saying "file" in the paragraphs above I am actually not telling

.. Note::



   1. In saying "file" in the paragraphs above I am actually not telling

      the whole truth. System V locking is based on fcntl(). The granularity of

fcntl() is such that it allows the locking of byte ranges in files, in addition

to entire files, so the mandatory locking rules also have byte level

granularity.

      fcntl() is such that it allows the locking of byte ranges in files, in

      addition to entire files, so the mandatory locking rules also have byte

      level granularity.



Note 2: POSIX.1 does not specify any scheme for mandatory locking, despite

   2. POSIX.1 does not specify any scheme for mandatory locking, despite

      borrowing the fcntl() locking scheme from System V. The mandatory locking

      scheme is defined by the System V Interface Definition (SVID) Version 3.

fs/locks.c

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@@ -61,7 +61,7 @@ 
 *

 *  Initial implementation of mandatory locks. SunOS turned out to be

 *  a rotten model, so I implemented the "obvious" semantics.

 *  See 'Documentation/filesystems/mandatory-locking.txt' for details.

 *  See 'Documentation/filesystems/mandatory-locking.rst' for details.

 *  Andy Walker (andy@lysaker.kvaerner.no), April 06, 1996.

 *

 *  Don't allow mandatory locks on mmap()'ed files. Added simple functions to

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