| Message ID | 20240823173332.281211-4-andrealmeid@igalia.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | tmpfs: Add case-insesitive support for tmpfs | expand |
Hi André,
kernel test robot noticed the following build warnings:
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Andr-Almeida/tmpfs-Add-casefold-lookup-support/20240826-135457
base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link: https://lore.kernel.org/r/20240823173332.281211-4-andrealmeid%40igalia.com
patch subject: [PATCH 3/5] tmpfs: Create casefold mount options
config: x86_64-randconfig-161-20240827 (https://download.01.org/0day-ci/archive/20240829/202408290349.lp2Eq74b-lkp@intel.com/config)
compiler: clang version 18.1.5 (https://github.com/llvm/llvm-project 617a15a9eac96088ae5e9134248d8236e34b91b1)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
| Closes: https://lore.kernel.org/r/202408290349.lp2Eq74b-lkp@intel.com/
smatch warnings:
mm/shmem.c:4307 shmem_parse_opt_casefold() error: uninitialized symbol 'maj'.
mm/shmem.c:4307 shmem_parse_opt_casefold() error: uninitialized symbol 'min'.
mm/shmem.c:4307 shmem_parse_opt_casefold() error: uninitialized symbol 'rev'.
vim +/maj +4307 mm/shmem.c
a024e87c2944676 André Almeida 2024-08-23 4291 static int shmem_parse_opt_casefold(struct fs_context *fc, struct fs_parameter *param)
a024e87c2944676 André Almeida 2024-08-23 4292 {
a024e87c2944676 André Almeida 2024-08-23 4293 struct shmem_options *ctx = fc->fs_private;
a024e87c2944676 André Almeida 2024-08-23 4294 unsigned int maj, min, rev, version_number;
a024e87c2944676 André Almeida 2024-08-23 4295 char version[10];
a024e87c2944676 André Almeida 2024-08-23 4296 int ret;
a024e87c2944676 André Almeida 2024-08-23 4297 struct unicode_map *encoding;
a024e87c2944676 André Almeida 2024-08-23 4298
a024e87c2944676 André Almeida 2024-08-23 4299 if (strncmp(param->string, "utf8-", 5))
a024e87c2944676 André Almeida 2024-08-23 4300 return invalfc(fc, "Only utf8 encondings are supported");
a024e87c2944676 André Almeida 2024-08-23 4301 ret = strscpy(version, param->string + 5, sizeof(version));
a024e87c2944676 André Almeida 2024-08-23 4302 if (ret < 0)
a024e87c2944676 André Almeida 2024-08-23 4303 return invalfc(fc, "Invalid enconding argument: %s",
a024e87c2944676 André Almeida 2024-08-23 4304 param->string);
a024e87c2944676 André Almeida 2024-08-23 4305
a024e87c2944676 André Almeida 2024-08-23 4306 utf8_parse_version(version, &maj, &min, &rev);
No error checking
a024e87c2944676 André Almeida 2024-08-23 @4307 version_number = UNICODE_AGE(maj, min, rev);
^^^^^^^^^^^^^
a024e87c2944676 André Almeida 2024-08-23 4308 encoding = utf8_load(version_number);
a024e87c2944676 André Almeida 2024-08-23 4309 if (IS_ERR(encoding))
a024e87c2944676 André Almeida 2024-08-23 4310 return invalfc(fc, "Invalid utf8 version: %s", version);
a024e87c2944676 André Almeida 2024-08-23 4311 pr_info("tmpfs: Using encoding provided by mount options: %s\n",
a024e87c2944676 André Almeida 2024-08-23 4312 param->string);
a024e87c2944676 André Almeida 2024-08-23 4313 ctx->encoding = encoding;
a024e87c2944676 André Almeida 2024-08-23 4314
a024e87c2944676 André Almeida 2024-08-23 4315 return 0;
a024e87c2944676 André Almeida 2024-08-23 4316 }
a024e87c2944676 André Almeida 2024-08-23 4317 #else
a024e87c2944676 André Almeida 2024-08-23 4318 static int shmem_parse_opt_casefold(struct fs_context *fc, struct fs_parameter *param)
a024e87c2944676 André Almeida 2024-08-23 4319 {
a024e87c2944676 André Almeida 2024-08-23 4320 return invalfc(fc, "tmpfs: No kernel support for casefold filesystems\n");
a024e87c2944676 André Almeida 2024-08-23 4321 }
diff --git a/mm/shmem.c b/mm/shmem.c index 67b6ab580ca2..5c77b4e73204 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -4102,6 +4102,8 @@ enum shmem_param { Opt_usrquota_inode_hardlimit, Opt_grpquota_block_hardlimit, Opt_grpquota_inode_hardlimit, + Opt_casefold, + Opt_strict_encoding, }; static const struct constant_table shmem_param_enums_huge[] = { @@ -4133,9 +4135,67 @@ const struct fs_parameter_spec shmem_fs_parameters[] = { fsparam_string("grpquota_block_hardlimit", Opt_grpquota_block_hardlimit), fsparam_string("grpquota_inode_hardlimit", Opt_grpquota_inode_hardlimit), #endif + fsparam_string("casefold", Opt_casefold), + fsparam_flag ("strict_encoding", Opt_strict_encoding), {} }; +#if IS_ENABLED(CONFIG_UNICODE) +static int utf8_parse_version(const char *version, unsigned int *maj, + unsigned int *min, unsigned int *rev) +{ + substring_t args[3]; + char version_string[12]; + static const struct match_token token[] = { + {1, "%d.%d.%d"}, + {0, NULL} + }; + + strscpy(version_string, version, sizeof(version_string)); + + if (match_token(version_string, token, args) != 1) + return -EINVAL; + + if (match_int(&args[0], maj) || match_int(&args[1], min) || + match_int(&args[2], rev)) + return -EINVAL; + + return 0; +} + +static int shmem_parse_opt_casefold(struct fs_context *fc, struct fs_parameter *param) +{ + struct shmem_options *ctx = fc->fs_private; + unsigned int maj, min, rev, version_number; + char version[10]; + int ret; + struct unicode_map *encoding; + + if (strncmp(param->string, "utf8-", 5)) + return invalfc(fc, "Only utf8 encondings are supported"); + ret = strscpy(version, param->string + 5, sizeof(version)); + if (ret < 0) + return invalfc(fc, "Invalid enconding argument: %s", + param->string); + + utf8_parse_version(version, &maj, &min, &rev); + version_number = UNICODE_AGE(maj, min, rev); + encoding = utf8_load(version_number); + if (IS_ERR(encoding)) + return invalfc(fc, "Invalid utf8 version: %s", version); + pr_info("tmpfs: Using encoding provided by mount options: %s\n", + param->string); + ctx->encoding = encoding; + + return 0; +} +#else +static int shmem_parse_opt_casefold(struct fs_context *fc, struct fs_parameter *param) +{ + return invalfc(fc, "tmpfs: No kernel support for casefold filesystems\n"); +} +#endif + static int shmem_parse_one(struct fs_context *fc, struct fs_parameter *param) { struct shmem_options *ctx = fc->fs_private; @@ -4294,6 +4354,11 @@ static int shmem_parse_one(struct fs_context *fc, struct fs_parameter *param) "Group quota inode hardlimit too large."); ctx->qlimits.grpquota_ihardlimit = size; break; + case Opt_casefold: + return shmem_parse_opt_casefold(fc, param); + case Opt_strict_encoding: + ctx->strict_encoding = true; + break; } return 0;
Most filesystems have their data stored in disk, so casefold option need to be enabled when building a filesystem on a device (via mkfs). However, as tmpfs is a RAM backed filesystem, there's no disk information and thus no mkfs to store information about casefold. For tmpfs, create casefold options for mounting. Userspace can then enable casefold support for a mount point using: $ mount -t tmpfs -o casefold=utf8-12.1.0 fs_name mount_dir/ Userspace must set what Unicode standard is aiming to. The available options depends on what the kernel Unicode subsystem supports. And for strict encoding: $ mount -t tmpfs -o casefold=utf8-12.1.0,strict_encoding fs_name mount_dir/ Strict encoding means that tmpfs will refuse to create invalid UTF-8 sequences. When this option is not enabled, any invalid sequence will be treated as an opaque byte sequence, ignoring the encoding thus not being able to be looked up in a case-insensitive way. Signed-off-by: André Almeida <andrealmeid@igalia.com> --- mm/shmem.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+)