[10/11] 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>
---
 fs/unicode/Kconfig                            | 13 ++++-
 fs/unicode/Makefile                           | 13 ++---
 fs/unicode/mkutf8data.c                       | 24 ++++++++--
 fs/unicode/utf8-core.c                        | 35 +++++++++++---
 fs/unicode/utf8-norm.c                        | 48 ++++---------------
 fs/unicode/utf8-selftest.c                    | 16 +++----
 ...{utf8data.h_shipped => utf8data.c_shipped} | 22 +++++++--
 fs/unicode/utf8n.h                            | 40 ++++++++--------
 include/linux/unicode.h                       |  2 +
 9 files changed, 123 insertions(+), 90 deletions(-)
 rename fs/unicode/{utf8data.h_shipped => utf8data.c_shipped} (99%)

Christoph Hellwig <hch@lst.de> writes:

> 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>
> ---
>  fs/unicode/Kconfig                            | 13 ++++-
>  fs/unicode/Makefile                           | 13 ++---
>  fs/unicode/mkutf8data.c                       | 24 ++++++++--
>  fs/unicode/utf8-core.c                        | 35 +++++++++++---
>  fs/unicode/utf8-norm.c                        | 48 ++++---------------
>  fs/unicode/utf8-selftest.c                    | 16 +++----
>  ...{utf8data.h_shipped => utf8data.c_shipped} | 22 +++++++--
>  fs/unicode/utf8n.h                            | 40 ++++++++--------
>  include/linux/unicode.h                       |  2 +
>  9 files changed, 123 insertions(+), 90 deletions(-)
>  rename fs/unicode/{utf8data.h_shipped => utf8data.c_shipped} (99%)
>
> diff --git a/fs/unicode/Kconfig b/fs/unicode/Kconfig
> index 2c27b9a5cd6ce..610d7bc05d6e3 100644
> --- a/fs/unicode/Kconfig
> +++ b/fs/unicode/Kconfig
> @@ -8,7 +8,16 @@ config UNICODE
>  	  Say Y here to enable UTF-8 NFD normalization and NFD+CF casefolding
>  	  support.
>  
> +config UNICODE_UTF8_DATA
> +	tristate "UTF-8 normalization and casefolding tables"
> +	depends on UNICODE
> +	default UNICODE
> +	help
> +	  This contains a large table of case foldings, which can be loaded as
> +	  a separate module if you say M here.  To be on the safe side stick
> +	  to the default of Y.  Saying N here makes no sense, if you do not want
> +	  utf8 casefolding support, disable CONFIG_UNICODE instead.
> +
>  config UNICODE_NORMALIZATION_SELFTEST
>  	tristate "Test UTF-8 normalization support"
> -	depends on UNICODE
> -	default n
> +	depends on UNICODE_UTF8_DATA
> diff --git a/fs/unicode/Makefile b/fs/unicode/Makefile
> index b88aecc865502..2f9d9188852b5 100644
> --- a/fs/unicode/Makefile
> +++ b/fs/unicode/Makefile
> @@ -2,14 +2,15 @@
>  
>  obj-$(CONFIG_UNICODE) += unicode.o
>  obj-$(CONFIG_UNICODE_NORMALIZATION_SELFTEST) += utf8-selftest.o
> +obj-$(CONFIG_UNICODE_UTF8_DATA) += utf8data.o
>  
>  unicode-y := utf8-norm.o utf8-core.o
>  
> -$(obj)/utf8-norm.o: $(obj)/utf8data.h
> +$(obj)/utf8-data.o: $(obj)/utf8data.c
>  
> -# In the normal build, the checked-in utf8data.h is just shipped.
> +# In the normal build, the checked-in utf8data.c is just shipped.
>  #
> -# To generate utf8data.h from UCD, put *.txt files in this directory
> +# To generate utf8data.c from UCD, put *.txt files in this directory
>  # and pass REGENERATE_UTF8DATA=1 from the command line.
>  ifdef REGENERATE_UTF8DATA
>  
> @@ -24,15 +25,15 @@ quiet_cmd_utf8data = GEN     $@
>  		-t $(srctree)/$(src)/NormalizationTest.txt \
>  		-o $@
>  
> -$(obj)/utf8data.h: $(obj)/mkutf8data $(filter %.txt, $(cmd_utf8data)) FORCE
> +$(obj)/utf8data.c: $(obj)/mkutf8data $(filter %.txt, $(cmd_utf8data)) FORCE
>  	$(call if_changed,utf8data)
>  
>  else
>  
> -$(obj)/utf8data.h: $(src)/utf8data.h_shipped FORCE
> +$(obj)/utf8data.c: $(src)/utf8data.c_shipped FORCE
>  	$(call if_changed,shipped)
>  
>  endif
>  
> -targets += utf8data.h
> +targets += utf8data.c
>  hostprogs += mkutf8data
> diff --git a/fs/unicode/mkutf8data.c b/fs/unicode/mkutf8data.c
> index ff2025ac5a325..bc1a7c8b5c8df 100644
> --- a/fs/unicode/mkutf8data.c
> +++ b/fs/unicode/mkutf8data.c
> @@ -3287,12 +3287,10 @@ static void write_file(void)
>  		open_fail(utf8_name, errno);
>  
>  	fprintf(file, "/* This file is generated code, do not edit. */\n");
> -	fprintf(file, "#ifndef __INCLUDED_FROM_UTF8NORM_C__\n");
> -	fprintf(file, "#error Only nls_utf8-norm.c should include this file.\n");
> -	fprintf(file, "#endif\n");
>  	fprintf(file, "\n");
> -	fprintf(file, "static const unsigned int utf8vers = %#x;\n",
> -		unicode_maxage);
> +	fprintf(file, "#include <linux/module.h>\n");
> +	fprintf(file, "#include <linux/kernel.h>\n");
> +	fprintf(file, "#include \"utf8n.h\"\n");
>  	fprintf(file, "\n");
>  	fprintf(file, "static const unsigned int utf8agetab[] = {\n");
>  	for (i = 0; i != ages_count; i++)
> @@ -3339,6 +3337,22 @@ static void write_file(void)
>  		fprintf(file, "\n");
>  	}
>  	fprintf(file, "};\n");
> +	fprintf(file, "\n");
> +	fprintf(file, "struct utf8data_table utf8_data_table = {\n");
> +	fprintf(file, "\t.utf8agetab = utf8agetab,\n");
> +	fprintf(file, "\t.utf8agetab_size = ARRAY_SIZE(utf8agetab),\n");
> +	fprintf(file, "\n");
> +	fprintf(file, "\t.utf8nfdicfdata = utf8nfdicfdata,\n");
> +	fprintf(file, "\t.utf8nfdicfdata_size = ARRAY_SIZE(utf8nfdicfdata),\n");
> +	fprintf(file, "\n");
> +	fprintf(file, "\t.utf8nfdidata = utf8nfdidata,\n");
> +	fprintf(file, "\t.utf8nfdidata_size = ARRAY_SIZE(utf8nfdidata),\n");
> +	fprintf(file, "\n");
> +	fprintf(file, "\t.utf8data = utf8data,\n");
> +	fprintf(file, "};\n");
> +	fprintf(file, "EXPORT_SYMBOL_GPL(utf8_data_table);");
> +	fprintf(file, "\n");
> +	fprintf(file, "MODULE_LICENSE(\"GPL v2\");\n");
>  	fclose(file);
>  }
>  
> diff --git a/fs/unicode/utf8-core.c b/fs/unicode/utf8-core.c
> index d9f713d38c0ad..38ca824f10158 100644
> --- a/fs/unicode/utf8-core.c
> +++ b/fs/unicode/utf8-core.c
> @@ -160,25 +160,45 @@ int utf8_normalize(const struct unicode_map *um, const struct qstr *str,
>  }
>  EXPORT_SYMBOL(utf8_normalize);
>  
> +static const struct utf8data *find_table_version(const struct utf8data *table,
> +		size_t nr_entries, unsigned int version)
> +{
> +	size_t i = nr_entries - 1;
> +
> +	while (version < table[i].maxage)
> +		i--;
> +	if (version > table[i].maxage)
> +		return NULL;
> +	return &table[i];
> +}
> +
>  struct unicode_map *utf8_load(unsigned int version)
>  {
>  	struct unicode_map *um;
>  
> -	if (!utf8version_is_supported(version))
> -		return ERR_PTR(-EINVAL);
> -
>  	um = kzalloc(sizeof(struct unicode_map), GFP_KERNEL);
>  	if (!um)
>  		return ERR_PTR(-ENOMEM);
>  	um->version = version;
> -	um->ntab[UTF8_NFDI] = utf8nfdi(version);
> -	if (!um->ntab[UTF8_NFDI])
> +
> +	um->tables = symbol_request(utf8_data_table);
> +	if (!um->tables)
>  		goto out_free_um;
> -	um->ntab[UTF8_NFDICF] = utf8nfdicf(version);
> +
> +	if (!utf8version_is_supported(um, version))
> +		goto out_symbol_put;
> +	um->ntab[UTF8_NFDI] = find_table_version(um->tables->utf8nfdidata,
> +			um->tables->utf8nfdidata_size, um->version);
> +	if (!um->ntab[UTF8_NFDI])
> +		goto out_symbol_put;
> +	um->ntab[UTF8_NFDICF] = find_table_version(um->tables->utf8nfdicfdata,
> +			um->tables->utf8nfdicfdata_size, um->version);
>  	if (!um->ntab[UTF8_NFDICF])
> -		goto out_free_um;
> +		goto out_symbol_put;
>  	return um;
>  
> +out_symbol_put:
> +	symbol_put(um->tables);
>  out_free_um:
>  	kfree(um);
>  	return ERR_PTR(-EINVAL);
> @@ -187,6 +207,7 @@ EXPORT_SYMBOL(utf8_load);
>  
>  void utf8_unload(struct unicode_map *um)
>  {
> +	symbol_put(utf8_data_table);

This triggers a BUG_ON if the symbol isn't loaded/loadable,
i.e. ext4_fill_super fails early.  I'm not sure how to fix it, though.


 Failed to find symbol utf8_data_table
 ------------[ cut here ]------------
 kernel BUG at kernel/module.c:1022!
 invalid opcode: 0000 [#1] SMP
 CPU: 1 PID: 387 Comm: mount Not tainted 5.15.0-rc4-for-next_5.15 #5
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
 RIP: 0010:__symbol_put+0x88/0x90
 Code: 84 c0 74 26 48 8b 7c 24 10 e8 44 f9 ff ff 65 ff 0d 1d 44 ea 7e 48 8b 44 24 30 65 48 33 04 25 28 00 00 00 75 07 48 83 c4 38 c3 <0f> 0b e8 51 ca a9 00 90 0f 1f 44 00 00 48 63 46 04 48 8d 74

 RSP: 0018:ffffc90000623cc0 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: ffff888102e91490 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: ffff88813b9d7860 RDI: ffff88813b9d7868
 RBP: ffffc90000623de0 R08: 0000000000000000 R09: c0000000ffffefff
 R10: ffffc900006239d8 R11: ffffc900006239d0 R12: 00000000ffffffea
 R13: 0000000000000000 R14: ffff888102e94000 R15: ffff888102e91000
 FS:  00007efcab508800(0000) GS:ffff88813b800000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007ff08eec56f4 CR3: 0000000102f31000 CR4: 00000000000006e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  ext4_fill_super+0x289/0x32b0
  ? bdev_name.isra.7+0x53/0xd0
  ? vsnprintf+0x379/0x520
  ? ext4_enable_quotas+0x260/0x260
  ? mount_bdev+0x18a/0x1c0
  ? ext4_enable_quotas+0x260/0x260
  mount_bdev+0x18a/0x1c0
  legacy_get_tree+0x30/0x50
  vfs_get_tree+0x23/0x90
  ? ns_capable_common+0x2b/0x50
  path_mount+0x6da/0xa50
  ? kmem_cache_free+0xf4/0x140
  do_mount+0x75/0x90
  __x64_sys_mount+0xc4/0xe0
  do_syscall_64+0x3a/0xb0
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7efcab71f6ba
 Code: 48 8b 0d b1 f7 0b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 7e f7 0b 00 f7 d8 64 89

 RSP: 002b:00007ffefb824338 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
 RAX: ffffffffffffffda RBX: 00007efcab873264 RCX: 00007efcab71f6ba
 RDX: 000055a2867dad10 RSI: 000055a2867d40f0 RDI: 000055a2867d40d0
 RBP: 000055a2867d3ea0 R08: 0000000000000000 R09: 000055a2867d3010
 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
 R13: 000055a2867d40d0 R14: 000055a2867dad10 R15: 000055a2867d3ea0
 Modules linked in:
 ---[ end trace abcd43d820168730 ]---



>  	kfree(um);
>  }
>  EXPORT_SYMBOL(utf8_unload);
> diff --git a/fs/unicode/utf8-norm.c b/fs/unicode/utf8-norm.c
> index 7c1f28ab31a80..829c7e2ad764a 100644
> --- a/fs/unicode/utf8-norm.c
> +++ b/fs/unicode/utf8-norm.c
> @@ -6,21 +6,12 @@
>  
>  #include "utf8n.h"
>  
> -struct utf8data {
> -	unsigned int maxage;
> -	unsigned int offset;
> -};
> -
> -#define __INCLUDED_FROM_UTF8NORM_C__
> -#include "utf8data.h"
> -#undef __INCLUDED_FROM_UTF8NORM_C__
> -
> -int utf8version_is_supported(unsigned int version)
> +int utf8version_is_supported(const struct unicode_map *um, unsigned int version)
>  {
> -	int i = ARRAY_SIZE(utf8agetab) - 1;
> +	int i = um->tables->utf8agetab_size - 1;
>  
> -	while (i >= 0 && utf8agetab[i] != 0) {
> -		if (version == utf8agetab[i])
> +	while (i >= 0 && um->tables->utf8agetab[i] != 0) {
> +		if (version == um->tables->utf8agetab[i])
>  			return 1;
>  		i--;
>  	}
> @@ -161,7 +152,7 @@ typedef const unsigned char utf8trie_t;
>   * underlying datatype: unsigned char.
>   *
>   * leaf[0]: The unicode version, stored as a generation number that is
> - *          an index into utf8agetab[].  With this we can filter code
> + *          an index into ->utf8agetab[].  With this we can filter code
>   *          points based on the unicode version in which they were
>   *          defined.  The CCC of a non-defined code point is 0.
>   * leaf[1]: Canonical Combining Class. During normalization, we need
> @@ -313,7 +304,7 @@ static utf8leaf_t *utf8nlookup(const struct unicode_map *um,
>  		enum utf8_normalization n, unsigned char *hangul, const char *s,
>  		size_t len)
>  {
> -	utf8trie_t	*trie = utf8data + um->ntab[n]->offset;
> +	utf8trie_t	*trie = um->tables->utf8data + um->ntab[n]->offset;
>  	int		offlen;
>  	int		offset;
>  	int		mask;
> @@ -404,7 +395,8 @@ ssize_t utf8nlen(const struct unicode_map *um, enum utf8_normalization n,
>  		leaf = utf8nlookup(um, n, hangul, s, len);
>  		if (!leaf)
>  			return -1;
> -		if (utf8agetab[LEAF_GEN(leaf)] > um->ntab[n]->maxage)
> +		if (um->tables->utf8agetab[LEAF_GEN(leaf)] >
> +		    um->ntab[n]->maxage)
>  			ret += utf8clen(s);
>  		else if (LEAF_CCC(leaf) == DECOMPOSE)
>  			ret += strlen(LEAF_STR(leaf));
> @@ -520,7 +512,7 @@ int utf8byte(struct utf8cursor *u8c)
>  
>  		ccc = LEAF_CCC(leaf);
>  		/* Characters that are too new have CCC 0. */
> -		if (utf8agetab[LEAF_GEN(leaf)] >
> +		if (u8c->um->tables->utf8agetab[LEAF_GEN(leaf)] >
>  		    u8c->um->ntab[u8c->n]->maxage) {
>  			ccc = STOPPER;
>  		} else if (ccc == DECOMPOSE) {
> @@ -597,25 +589,3 @@ int utf8byte(struct utf8cursor *u8c)
>  	}
>  }
>  EXPORT_SYMBOL(utf8byte);
> -
> -const struct utf8data *utf8nfdi(unsigned int maxage)
> -{
> -	int i = ARRAY_SIZE(utf8nfdidata) - 1;
> -
> -	while (maxage < utf8nfdidata[i].maxage)
> -		i--;
> -	if (maxage > utf8nfdidata[i].maxage)
> -		return NULL;
> -	return &utf8nfdidata[i];
> -}
> -
> -const struct utf8data *utf8nfdicf(unsigned int maxage)
> -{
> -	int i = ARRAY_SIZE(utf8nfdicfdata) - 1;
> -
> -	while (maxage < utf8nfdicfdata[i].maxage)
> -		i--;
> -	if (maxage > utf8nfdicfdata[i].maxage)
> -		return NULL;
> -	return &utf8nfdicfdata[i];
> -}
> diff --git a/fs/unicode/utf8-selftest.c b/fs/unicode/utf8-selftest.c
> index cfa3832b75f42..eb2bbdd688d71 100644
> --- a/fs/unicode/utf8-selftest.c
> +++ b/fs/unicode/utf8-selftest.c
> @@ -255,21 +255,21 @@ static void check_utf8_comparisons(struct unicode_map *table)
>  	}
>  }
>  
> -static void check_supported_versions(void)
> +static void check_supported_versions(struct unicode_map *um)
>  {
>  	/* Unicode 7.0.0 should be supported. */
> -	test(utf8version_is_supported(UNICODE_AGE(7, 0, 0)));
> +	test(utf8version_is_supported(um, UNICODE_AGE(7, 0, 0)));
>  
>  	/* Unicode 9.0.0 should be supported. */
> -	test(utf8version_is_supported(UNICODE_AGE(9, 0, 0)));
> +	test(utf8version_is_supported(um, UNICODE_AGE(9, 0, 0)));
>  
>  	/* Unicode 1x.0.0 (the latest version) should be supported. */
> -	test(utf8version_is_supported(UTF8_LATEST));
> +	test(utf8version_is_supported(um, UTF8_LATEST));
>  
>  	/* Next versions don't exist. */
> -	test(!utf8version_is_supported(UNICODE_AGE(13, 0, 0)));
> -	test(!utf8version_is_supported(UNICODE_AGE(0, 0, 0)));
> -	test(!utf8version_is_supported(UNICODE_AGE(-1, -1, -1)));
> +	test(!utf8version_is_supported(um, UNICODE_AGE(13, 0, 0)));
> +	test(!utf8version_is_supported(um, UNICODE_AGE(0, 0, 0)));
> +	test(!utf8version_is_supported(um, UNICODE_AGE(-1, -1, -1)));
>  }
>  
>  static int __init init_test_ucd(void)
> @@ -285,7 +285,7 @@ static int __init init_test_ucd(void)
>  		return PTR_ERR(um);
>  	}
>  
> -	check_supported_versions();
> +	check_supported_versions(um);
>  	check_utf8_nfdi(um);
>  	check_utf8_nfdicf(um);
>  	check_utf8_comparisons(um);
> diff --git a/fs/unicode/utf8data.h_shipped b/fs/unicode/utf8data.c_shipped
> similarity index 99%
> rename from fs/unicode/utf8data.h_shipped
> rename to fs/unicode/utf8data.c_shipped
> index 76e4f0e1b0891..d9b62901aa96b 100644
> --- a/fs/unicode/utf8data.h_shipped
> +++ b/fs/unicode/utf8data.c_shipped
> @@ -1,9 +1,8 @@
>  /* This file is generated code, do not edit. */
> -#ifndef __INCLUDED_FROM_UTF8NORM_C__
> -#error Only nls_utf8-norm.c should include this file.
> -#endif
>  
> -static const unsigned int utf8vers = 0xc0100;
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include "utf8n.h"
>  
>  static const unsigned int utf8agetab[] = {
>  	0,
> @@ -4107,3 +4106,18 @@ static const unsigned char utf8data[64256] = {
>  	0x52,0x04,0x00,0x00,0x11,0x04,0x00,0x00,0x02,0x00,0xcf,0x86,0xcf,0x06,0x02,0x00,
>  	0x81,0x80,0xcf,0x86,0x85,0x84,0xcf,0x86,0xcf,0x06,0x02,0x00,0x00,0x00,0x00,0x00
>  };
> +
> +struct utf8data_table utf8_data_table = {
> +	.utf8agetab = utf8agetab,
> +	.utf8agetab_size = ARRAY_SIZE(utf8agetab),
> +
> +	.utf8nfdicfdata = utf8nfdicfdata,
> +	.utf8nfdicfdata_size = ARRAY_SIZE(utf8nfdicfdata),
> +
> +	.utf8nfdidata = utf8nfdidata,
> +	.utf8nfdidata_size = ARRAY_SIZE(utf8nfdidata),
> +
> +	.utf8data = utf8data,
> +};
> +EXPORT_SYMBOL_GPL(utf8_data_table);
> +MODULE_LICENSE("GPL v2");
> diff --git a/fs/unicode/utf8n.h b/fs/unicode/utf8n.h
> index 206c89f0dbf71..bd00d587747a7 100644
> --- a/fs/unicode/utf8n.h
> +++ b/fs/unicode/utf8n.h
> @@ -13,25 +13,7 @@
>  #include <linux/module.h>
>  #include <linux/unicode.h>
>  
> -int utf8version_is_supported(unsigned int version);
> -
> -/*
> - * Look for the correct const struct utf8data for a unicode version.
> - * Returns NULL if the version requested is too new.
> - *
> - * 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).
> - */
> -extern const struct utf8data *utf8nfdi(unsigned int maxage);
> -extern const struct utf8data *utf8nfdicf(unsigned int maxage);
> +int utf8version_is_supported(const struct unicode_map *um, unsigned int version);
>  
>  /*
>   * Determine the length of the normalized from of the string,
> @@ -78,4 +60,24 @@ int utf8ncursor(struct utf8cursor *u8c, const struct unicode_map *um,
>   */
>  extern int utf8byte(struct utf8cursor *u8c);
>  
> +struct utf8data {
> +	unsigned int maxage;
> +	unsigned int offset;
> +};
> +
> +struct utf8data_table {
> +	const unsigned int *utf8agetab;
> +	int utf8agetab_size;
> +
> +	const struct utf8data *utf8nfdicfdata;
> +	int utf8nfdicfdata_size;
> +
> +	const struct utf8data *utf8nfdidata;
> +	int utf8nfdidata_size;
> +
> +	const unsigned char *utf8data;
> +};
> +
> +extern struct utf8data_table utf8_data_table;
> +
>  #endif /* UTF8NORM_H */
> diff --git a/include/linux/unicode.h b/include/linux/unicode.h
> index 526ca8b8391a5..4d39e6e11a950 100644
> --- a/include/linux/unicode.h
> +++ b/include/linux/unicode.h
> @@ -6,6 +6,7 @@
>  #include <linux/dcache.h>
>  
>  struct utf8data;
> +struct utf8data_table;
>  
>  #define UNICODE_MAJ_SHIFT		16
>  #define UNICODE_MIN_SHIFT		8
> @@ -49,6 +50,7 @@ enum utf8_normalization {
>  struct unicode_map {
>  	unsigned int version;
>  	const struct utf8data *ntab[UTF8_NMAX];
> +	const struct utf8data_table *tables;
>  };
>  
>  int utf8_validate(const struct unicode_map *um, const struct qstr *str);

[fullquote deleted]

On Tue, Oct 12, 2021 at 08:25:23AM -0300, Gabriel Krisman Bertazi wrote:
> > @@ -187,6 +207,7 @@ EXPORT_SYMBOL(utf8_load);
> >  
> >  void utf8_unload(struct unicode_map *um)
> >  {
> > +	symbol_put(utf8_data_table);
> 
> This triggers a BUG_ON if the symbol isn't loaded/loadable,
> i.e. ext4_fill_super fails early.  I'm not sure how to fix it, though.

Does this fix it?

diff --git a/fs/unicode/utf8-core.c b/fs/unicode/utf8-core.c
index 38ca824f10158..67aaadc3ab072 100644
--- a/fs/unicode/utf8-core.c
+++ b/fs/unicode/utf8-core.c
@@ -207,8 +207,10 @@ EXPORT_SYMBOL(utf8_load);
 
 void utf8_unload(struct unicode_map *um)
 {
-	symbol_put(utf8_data_table);
-	kfree(um);
+	if (um) {
+		symbol_put(utf8_data_table);
+		kfree(um);
+	}
 }
 EXPORT_SYMBOL(utf8_unload);

Christoph Hellwig <hch@lst.de> writes:

> [fullquote deleted]
>
> On Tue, Oct 12, 2021 at 08:25:23AM -0300, Gabriel Krisman Bertazi wrote:
>> > @@ -187,6 +207,7 @@ EXPORT_SYMBOL(utf8_load);
>> >  
>> >  void utf8_unload(struct unicode_map *um)
>> >  {
>> > +	symbol_put(utf8_data_table);
>> 
>> This triggers a BUG_ON if the symbol isn't loaded/loadable,
>> i.e. ext4_fill_super fails early.  I'm not sure how to fix it, though.
>
> Does this fix it?

Yes, it does.

I  will fold this into the original patch and queue this series for 5.16.

Thank you,

On Tue, Oct 12, 2021 at 11:40:56AM -0300, Gabriel Krisman Bertazi wrote:
> > Does this fix it?
> 
> Yes, it does.
> 
> I  will fold this into the original patch and queue this series for 5.16.

This series still doesn't seem to be queued up.

Christoph Hellwig <hch@lst.de> writes:

> On Tue, Oct 12, 2021 at 11:40:56AM -0300, Gabriel Krisman Bertazi wrote:
>> > Does this fix it?
>> 
>> Yes, it does.
>> 
>> I  will fold this into the original patch and queue this series for 5.16.
>
> This series still doesn't seem to be queued up.

Hm, I'm keeping it here:

https://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode.git/log/?h=for-next_5.16

Sorry, but I'm not sure what is the process to get tracked by
linux-next.  I'm Cc'ing Stephen to hopefully help me figure it out.

Thanks,

Hi Gabriel,

On Tue, 26 Oct 2021 10:56:20 -0300 Gabriel Krisman Bertazi <krisman@collabora.com> wrote:
>
> Christoph Hellwig <hch@lst.de> writes:
> 
> > On Tue, Oct 12, 2021 at 11:40:56AM -0300, Gabriel Krisman Bertazi wrote:  
> >> > Does this fix it?  
> >> 
> >> Yes, it does.
> >> 
> >> I  will fold this into the original patch and queue this series for 5.16.  
> >
> > This series still doesn't seem to be queued up.  
> 
> Hm, I'm keeping it here:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode.git/log/?h=for-next_5.16
> 
> Sorry, but I'm not sure what is the process to get tracked by
> linux-next.  I'm Cc'ing Stephen to hopefully help me figure it out.

You just need to send me a git URL for your tree/branch (not a cgit or
gitweb URL, please), plus some idea of what the tree include and how it
is sent to Linus (directly or via another tree).  The branch should
have a generic name (i.e. not including a version) as I will continuet
to fetch that branch every day until you tell me to stop.  When your
code is ready to be included in linux-next, all you have to do is
update that branch to include the new code.

Stephen Rothwell <sfr@canb.auug.org.au> writes:

> You just need to send me a git URL for your tree/branch (not a cgit or
> gitweb URL, please), plus some idea of what the tree include and how it
> is sent to Linus (directly or via another tree).  The branch should
> have a generic name (i.e. not including a version) as I will continuet
> to fetch that branch every day until you tell me to stop.  When your
> code is ready to be included in linux-next, all you have to do is
> update that branch to include the new code.

Hi Stephen,

Thanks for the information.

I'd like to ask you to track the branch 'for-next' of the following repository:

git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode.git

This branch is used as a staging area for development of the Unicode
subsystem used by native case-insensitive filesystems for file name
normalization and casefolding.  It goes to Linus through Ted Ts'o's ext4
tree.

Thank you,

Hi Gabriel,

On Wed, 27 Oct 2021 23:00:55 -0300 Gabriel Krisman Bertazi <krisman@collabora.com> wrote:
>> 
> I'd like to ask you to track the branch 'for-next' of the following repository:
> 
> git://git.kernel.org/pub/scm/linux/kernel/git/krisman/unicode.git
> 
> This branch is used as a staging area for development of the Unicode
> subsystem used by native case-insensitive filesystems for file name
> normalization and casefolding.  It goes to Linus through Ted Ts'o's ext4
> tree.

Added from today.

Thanks for adding your subsystem tree as a participant of linux-next.  As
you may know, this is not a judgement of your code.  The purpose of
linux-next is for integration testing and to lower the impact of
conflicts between subsystems in the next merge window. 

You will need to ensure that the patches/commits in your tree/series have
been:
     * submitted under GPL v2 (or later) and include the Contributor's
        Signed-off-by,
     * posted to the relevant mailing list,
     * reviewed by you (or another maintainer of your subsystem tree),
     * successfully unit tested, and 
     * destined for the current or next Linux merge window.

Basically, this should be just what you would send to Linus (or ask him
to fetch).  It is allowed to be rebased if you deem it necessary.