Commit Graph

31 Commits

Author SHA1 Message Date
Linus Torvalds
630c12862c Fix from Christoph Hellwig merging the CONFIG_UNICODE_UTF8_DATA into the
previous CONFIG_UNICODE.  It is -rc material since we don't want to
 expose the former symbol on 5.17.
 
 This has been living on linux-next for the past week.
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Merge tag 'unicode-for-next-5.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode

Pull unicode cleanup from Gabriel Krisman Bertazi:
 "A fix from Christoph Hellwig merging the CONFIG_UNICODE_UTF8_DATA into
  the previous CONFIG_UNICODE. It is -rc material since we don't want to
  expose the former symbol on 5.17.

  This has been living on linux-next for the past week"

* tag 'unicode-for-next-5.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode:
  unicode: clean up the Kconfig symbol confusion
2022-02-01 11:13:24 -08:00
Christoph Hellwig
5298d4bfe8 unicode: clean up the Kconfig symbol confusion
Turn the CONFIG_UNICODE symbol into a tristate that generates some always
built in code and remove the confusing CONFIG_UNICODE_UTF8_DATA symbol.

Note that a lot of the IS_ENABLED() checks could be turned from cpp
statements into normal ifs, but this change is intended to be fairly
mechanic, so that should be cleaned up later.

Fixes: 2b3d047870 ("unicode: Add utf8-data module")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2022-01-20 19:57:24 -05:00
Linus Torvalds
98f2345773 unicode: fix .gitignore for generated utfdata file
Commit 2b3d047870 ("unicode: Add utf8-data module") changed the
generated utf8data file from 'utf8data.h' to 'utf8data.c', but didn't
change the comments or the .gitignore to match.

The comments should be updated too, but at least they don't cause any
visible breakage.  But the gitignore file needs changing to avoid git
complaining about untracked files.

Fixes: 2b3d047870 ("unicode: Add utf8-data module")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-17 07:26:43 +02:00
Christoph Hellwig
e2a58d2d34 unicode: only export internal symbols for the selftests
The exported symbols in utf8-norm.c are not needed for normal
file system consumers, so move them to conditional _GPL exports
just for the selftest.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2021-10-12 11:41:39 -03:00
Christoph Hellwig
2b3d047870 unicode: Add utf8-data module
utf8data.h contains a large database table which is an auto-generated
decodification trie for the unicode normalization functions.

Allow building it into a separate module.

Based on a patch from Shreeya Patel <shreeya.patel@collabora.com>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2021-10-12 11:41:39 -03:00
Christoph Hellwig
6ca99ce756 unicode: cache the normalization tables in struct unicode_map
Instead of repeatedly looking up the version add pointers to the
NFD and NFD+CF tables to struct unicode_map, and pass a
unicode_map plus index to the functions using the normalization
tables.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2021-10-11 17:02:02 -03:00
Christoph Hellwig
fbc59d6505 unicode: move utf8cursor to utf8-selftest.c
Only used by the tests, so no need to keep it in the core.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2021-10-11 17:01:58 -03:00
Christoph Hellwig
9012d79cf0 unicode: simplify utf8len
Just use the utf8nlen implementation with a (size_t)-1 len argument,
similar to utf8_lookup.  Also move the function to utf8-selftest.c, as
it isn't used anywhere else.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2021-10-11 17:01:54 -03:00
Christoph Hellwig
379210db48 unicode: remove the unused utf8{,n}age{min,max} functions
No actually used anywhere.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2021-10-11 17:01:50 -03:00
Christoph Hellwig
49bd03cc7e unicode: pass a UNICODE_AGE() tripple to utf8_load
Don't bother with pointless string parsing when the caller can just pass
the version in the format that the core expects.  Also remove the
fallback to the latest version that none of the callers actually uses.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2021-10-11 17:01:46 -03:00
Christoph Hellwig
a440943e68 unicode: remove the charset field from struct unicode_map
It is hardcoded and only used for a f2fs sysfs file where it can be
hardcoded just as easily.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2021-10-11 17:01:35 -03:00
Masahiro Yamada
9009b45581 .gitignore: prefix local generated files with a slash
The pattern prefixed with '/' matches files in the same directory,
but not ones in sub-directories.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Andra Paraschiv <andraprs@amazon.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2021-05-02 00:43:35 +09:00
Daniel Rosenberg
3d7bfea8b8 unicode: Add utf8_casefold_hash
This adds a case insensitive hash function to allow taking the hash
without needing to allocate a casefolded copy of the string.

The existing d_hash implementations for casefolding allocate memory
within rcu-walk, by avoiding it we can be more efficient and avoid
worrying about a failed allocation.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-09-10 14:03:31 -07:00
Masahiro Yamada
d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Masahiro Yamada
5f2fb52fac kbuild: rename hostprogs-y/always to hostprogs/always-y
In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.

It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.

This commit renames like follows:

  always       ->  always-y
  hostprogs-y  ->  hostprogs

So, scripts/Makefile will look like this:

  always-$(CONFIG_BUILD_BIN2C) += ...
  always-$(CONFIG_KALLSYMS)    += ...
      ...
  hostprogs := $(always-y) $(always-m)

I think this makes more sense because a host program is always a host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.

The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-02-04 01:53:07 +09:00
Colin Ian King
aa28b98d6d unicode: make array 'token' static const, makes object smaller
Don't populate the array 'token' on the stack but instead make it
static const. Makes the object code smaller by 234 bytes.

Before:
   text	   data	    bss	    dec	    hex	filename
   5371	    272	      0	   5643	   160b	fs/unicode/utf8-core.o

After:
   text	   data	    bss	    dec	    hex	filename
   5041	    368	      0	   5409	   1521	fs/unicode/utf8-core.o

(gcc version 9.2.1, amd64)

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2019-09-17 11:48:24 -04:00
Krzysztof Wilczynski
334b427e96 unicode: Move static keyword to the front of declarations
Move the static keyword to the front of declarations of nfdi_test_data
and nfdicf_test_data, and resolve the following compiler warnings that
can be seen when building with warnings enabled (W=1):

fs/unicode/utf8-selftest.c:38:1: warning:
  ‘static’ is not at beginning of declaration [-Wold-style-declaration]

fs/unicode/utf8-selftest.c:92:1: warning:
  ‘static’ is not at beginning of declaration [-Wold-style-declaration]

Signed-off-by: Krzysztof Wilczynski <kw@linux.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2019-09-17 11:48:11 -04:00
Linus Torvalds
2e756758e5 Many bug fixes and cleanups, and an optimization for case-insensitive
lookups.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "Many bug fixes and cleanups, and an optimization for case-insensitive
  lookups"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix coverity warning on error path of filename setup
  ext4: replace ktype default_attrs with default_groups
  ext4: rename htree_inline_dir_to_tree() to ext4_inlinedir_to_tree()
  ext4: refactor initialize_dirent_tail()
  ext4: rename "dirent_csum" functions to use "dirblock"
  ext4: allow directory holes
  jbd2: drop declaration of journal_sync_buffer()
  ext4: use jbd2_inode dirty range scoping
  jbd2: introduce jbd2_inode dirty range scoping
  mm: add filemap_fdatawait_range_keep_errors()
  ext4: remove redundant assignment to node
  ext4: optimize case-insensitive lookups
  ext4: make __ext4_get_inode_loc plug
  ext4: clean up kerneldoc warnigns when building with W=1
  ext4: only set project inherit bit for directory
  ext4: enforce the immutable flag on open files
  ext4: don't allow any modifications to an immutable file
  jbd2: fix typo in comment of journal_submit_inode_data_buffers
  jbd2: fix some print format mistakes
  ext4: gracefully handle ext4_break_layouts() failure during truncate
2019-07-10 21:06:01 -07:00
Gabriel Krisman Bertazi
3ae72562ad ext4: optimize case-insensitive lookups
Temporarily cache a casefolded version of the file name under lookup in
ext4_filename, to avoid repeatedly casefolding it.  I got up to 30%
speedup on lookups of large directories (>100k entries), depending on
the length of the string under lookup.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-06-19 23:45:09 -04:00
Thomas Gleixner
9f8068503d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 294
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license 2 as published
  by the free software foundation this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation this program is distributed in the hope
  that it [would] be useful but without any warranty without even the
  implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 9 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.804956444@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:38 +02:00
Thomas Gleixner
9c92ab6191 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282
Based on 1 normalized pattern(s):

  this software is licensed under the terms of the gnu general public
  license version 2 as published by the free software foundation and
  may be copied distributed and modified under those terms this
  program is distributed in the hope that it will be useful but
  without any warranty without even the implied warranty of
  merchantability or fitness for a particular purpose see the gnu
  general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 285 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:37 +02:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Theodore Ts'o
7fb6413336 unicode: update to Unicode 12.1.0 final
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Gabriel Krisman Bertazi <krisman@collabora.com>
2019-05-12 13:26:08 -04:00
Theodore Ts'o
15f0d8d0ba unicode: add missing check for an error return from utf8lookup()
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Gabriel Krisman Bertazi <krisman@collabora.com>
2019-05-12 04:56:51 -04:00
Masahiro Yamada
28ba53c076 unicode: refactor the rule for regenerating utf8data.h
scripts/mkutf8data is used only when regenerating utf8data.h,
which never happens in the normal kernel build. However, it is
irrespectively built if CONFIG_UNICODE is enabled.

Moreover, there is no good reason for it to reside in the scripts/
directory since it is only used in fs/unicode/.

Hence, move it from scripts/ to fs/unicode/.

In some cases, we bypass build artifacts in the normal build. The
conventional way to do so is to surround the code with ifdef REGENERATE_*.

For example,

 - 7373f4f83c ("kbuild: add implicit rules for parser generation")
 - 6aaf49b495 ("crypto: arm,arm64 - Fix random regeneration of S_shipped")

I rewrote the rule in a more kbuild'ish style.

In the normal build, utf8data.h is just shipped from the check-in file.

$ make
  [ snip ]
  SHIPPED fs/unicode/utf8data.h
  CC      fs/unicode/utf8-norm.o
  CC      fs/unicode/utf8-core.o
  CC      fs/unicode/utf8-selftest.o
  AR      fs/unicode/built-in.a

If you want to generate utf8data.h based on UCD, put *.txt files into
fs/unicode/, then pass REGENERATE_UTF8DATA=1 from the command line.
The mkutf8data tool will be automatically compiled to generate the
utf8data.h from the *.txt files.

$ make REGENERATE_UTF8DATA=1
  [ snip ]
  HOSTCC  fs/unicode/mkutf8data
  GEN     fs/unicode/utf8data.h
  CC      fs/unicode/utf8-norm.o
  CC      fs/unicode/utf8-core.o
  CC      fs/unicode/utf8-selftest.o
  AR      fs/unicode/built-in.a

I renamed the check-in utf8data.h to utf8data.h_shipped so that this
will work for the out-of-tree build.

You can update it based on the latest UCD like this:

$ make REGENERATE_UTF8DATA=1 fs/unicode/
$ cp fs/unicode/utf8data.h fs/unicode/utf8data.h_shipped

Also, I added entries to .gitignore and dontdiff.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-04-28 13:45:36 -04:00
Gabriel Krisman Bertazi
1215d239e7 unicode: update unicode database unicode version 12.1.0
Regenerate utf8data.h based on the latest UCD files and run tests
against the latest version.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-04-25 13:59:17 -04:00
Gabriel Krisman Bertazi
f0d6cc0032 unicode: introduce test module for normalized utf8 implementation
This implements a in-kernel sanity test module for the utf8
normalization core.  At probe time, it will run basic sequences through
the utf8n core, to identify problems will equivalent sequences and
normalization/casefold code.  This is supposed to be useful for
regression testing when adding support for a new version of utf8 to
linux.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-04-25 13:56:01 -04:00
Gabriel Krisman Bertazi
9d53690f0d unicode: implement higher level API for string handling
This patch integrates the utf8n patches with some higher level API to
perform UTF-8 string comparison, normalization and casefolding
operations.  Implemented is a variation of NFD, and casefold is
performed by doing full casefold on top of NFD.  These algorithms are
based on the core implemented by Olaf Weber from SGI.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-04-25 13:51:22 -04:00
Olaf Weber
a8384c6879 unicode: reduce the size of utf8data[]
Remove the Hangul decompositions from the utf8data trie, and do
algorithmic decomposition to calculate them on the fly. To store the
decomposition the caller of utf8lookup()/utf8nlookup() must provide a
12-byte buffer, which is used to synthesize a leaf with the
decomposition. This significantly reduces the size of the utf8data[]
array.

Changes made by Gabriel:
  Rebase to mainline
  Fix checkpatch errors
  Extract robustness fixes and merge back to original mkutf8data.c patch
  Regenerate utf8data.h

Signed-off-by: Olaf Weber <olaf@sgi.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-04-25 13:49:18 -04:00
Olaf Weber
44594c2fbf unicode: introduce code for UTF-8 normalization
Supporting functions for UTF-8 normalization are in utf8norm.c with the
header utf8norm.h. Two normalization forms are supported: nfdi and
nfdicf.

  nfdi:
   - Apply unicode normalization form NFD.
   - Remove any Default_Ignorable_Code_Point.

  nfdicf:
   - Apply unicode normalization form NFD.
   - Remove any Default_Ignorable_Code_Point.
   - Apply a full casefold (C + F).

For the purposes of the code, a string is valid UTF-8 if:

 - The values encoded are 0x1..0x10FFFF.
 - The surrogate codepoints 0xD800..0xDFFFF are not encoded.
 - The shortest possible encoding is used for all values.

The supporting functions work on null-terminated strings (utf8 prefix)
and on length-limited strings (utf8n prefix).

From the original SGI patch and for conformity with coding standards,
the utf8data_t typedef was dropped, since it was just masking the struct
keyword.  On other occasions, namely utf8leaf_t and utf8trie_t, I
decided to keep it, since they are simple pointers to memory buffers,
and using uchars here wouldn't provide any more meaningful information.

From the original submission, we also converted from the compatibility
form to canonical.

Changes made by Gabriel:
  Rebase to Mainline
  Fix up checkpatch.pl warnings
  Drop typedefs
  move out of libxfs
  Convert from NFKD to NFD

Signed-off-by: Olaf Weber <olaf@sgi.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-04-25 13:45:46 -04:00
Gabriel Krisman Bertazi
955405d117 unicode: introduce UTF-8 character database
The decomposition and casefolding of UTF-8 characters are described in a
prefix tree in utf8data.h, which is a generate from the Unicode
Character Database (UCD), published by the Unicode Consortium, and
should not be edited by hand.  The structures in utf8data.h are meant to
be used for lookup operations by the unicode subsystem, when decoding a
utf-8 string.

mkutf8data.c is the source for a program that generates utf8data.h. It
was written by Olaf Weber from SGI and originally proposed to be merged
into Linux in 2014.  The original proposal performed the compatibility
decomposition, NFKD, but the current version was modified by me to do
canonical decomposition, NFD, as suggested by the community.  The
changes from the original submission are:

  * Rebase to mainline.
  * Fix out-of-tree-build.
  * Update makefile to build 11.0.0 ucd files.
  * drop references to xfs.
  * Convert NFKD to NFD.
  * Merge back robustness fixes from original patch. Requested by
    Dave Chinner.

The original submission is archived at:

<https://linux-xfs.oss.sgi.narkive.com/Xx10wjVY/rfc-unicode-utf-8-support-for-xfs>

The utf8data.h file can be regenerated using the instructions in
fs/unicode/README.utf8data.

- Notes on the update from 8.0.0 to 11.0:

The structure of the ucd files and special cases have not experienced
any changes between versions 8.0.0 and 11.0.0.  8.0.0 saw the addition
of Cherokee LC characters, which is an interesting case for
case-folding.  The update is accompanied by new tests on the test_ucd
module to catch specific cases.  No changes to mkutf8data script were
required for the updates.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-04-25 13:38:44 -04:00