From 626c3920aeb4575f53c96b0d4ad4e651a21cbb66 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 8 Sep 2019 20:28:06 -0400 Subject: [PATCH] shmem_parse_one(): switch to use of fs_parse() This thing will eventually become our ->parse_param(), while shmem_parse_options() - ->parse_monolithic(). At that point shmem_parse_options() will start calling vfs_parse_fs_string(), rather than calling shmem_parse_one() directly. Signed-off-by: Al Viro --- mm/shmem.c | 187 +++++++++++++++++++++++++++++++++-------------------- 1 file changed, 118 insertions(+), 69 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index b392a8263329..6a41595dd1b3 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -37,6 +37,7 @@ #include #include #include +#include #include /* for arch/microblaze update_mmu_cache() */ @@ -3363,15 +3364,63 @@ static const struct export_operations shmem_export_ops = { .fh_to_dentry = shmem_fh_to_dentry, }; -static int shmem_parse_one(struct shmem_options *ctx, char *opt, char *value) -{ - char *rest; - uid_t uid; - gid_t gid; +enum shmem_param { + Opt_gid, + Opt_huge, + Opt_mode, + Opt_mpol, + Opt_nr_blocks, + Opt_nr_inodes, + Opt_size, + Opt_uid, +}; - if (!strcmp(opt, "size")) { - unsigned long long size; - size = memparse(value,&rest); +static const struct fs_parameter_spec shmem_param_specs[] = { + fsparam_u32 ("gid", Opt_gid), + fsparam_enum ("huge", Opt_huge), + fsparam_u32oct("mode", Opt_mode), + fsparam_string("mpol", Opt_mpol), + fsparam_string("nr_blocks", Opt_nr_blocks), + fsparam_string("nr_inodes", Opt_nr_inodes), + fsparam_string("size", Opt_size), + fsparam_u32 ("uid", Opt_uid), + {} +}; + +static const struct fs_parameter_enum shmem_param_enums[] = { + { Opt_huge, "never", SHMEM_HUGE_NEVER }, + { Opt_huge, "always", SHMEM_HUGE_ALWAYS }, + { Opt_huge, "within_size", SHMEM_HUGE_WITHIN_SIZE }, + { Opt_huge, "advise", SHMEM_HUGE_ADVISE }, + {} +}; + +const struct fs_parameter_description shmem_fs_parameters = { + .name = "tmpfs", + .specs = shmem_param_specs, + .enums = shmem_param_enums, +}; + +static int shmem_parse_one(struct shmem_options *ctx, + struct fs_parameter *param) +{ + struct fs_context *fc = NULL; + struct fs_parse_result result; + unsigned long long size; + char *rest; + int opt; + + opt = fs_parse(fc, &shmem_fs_parameters, param, &result); + if (opt < 0) { + if (opt == -ENOPARAM) + return invalf(fc, "tmpfs: Unknown parameter '%s'", + param->key); + return opt; + } + + switch (opt) { + case Opt_size: + size = memparse(param->string, &rest); if (*rest == '%') { size <<= PAGE_SHIFT; size *= totalram_pages(); @@ -3379,74 +3428,65 @@ static int shmem_parse_one(struct shmem_options *ctx, char *opt, char *value) rest++; } if (*rest) - goto bad_val; + goto bad_value; ctx->blocks = DIV_ROUND_UP(size, PAGE_SIZE); ctx->seen |= SHMEM_SEEN_BLOCKS; - } else if (!strcmp(opt, "nr_blocks")) { - ctx->blocks = memparse(value, &rest); + break; + case Opt_nr_blocks: + ctx->blocks = memparse(param->string, &rest); if (*rest) - goto bad_val; + goto bad_value; ctx->seen |= SHMEM_SEEN_BLOCKS; - } else if (!strcmp(opt, "nr_inodes")) { - ctx->inodes = memparse(value, &rest); + break; + case Opt_nr_inodes: + ctx->inodes = memparse(param->string, &rest); if (*rest) - goto bad_val; + goto bad_value; ctx->seen |= SHMEM_SEEN_INODES; - } else if (!strcmp(opt, "mode")) { - ctx->mode = simple_strtoul(value, &rest, 8) & 07777; - if (*rest) - goto bad_val; - } else if (!strcmp(opt, "uid")) { - uid = simple_strtoul(value, &rest, 0); - if (*rest) - goto bad_val; - ctx->uid = make_kuid(current_user_ns(), uid); + break; + case Opt_mode: + ctx->mode = result.uint_32 & 07777; + break; + case Opt_uid: + ctx->uid = make_kuid(current_user_ns(), result.uint_32); if (!uid_valid(ctx->uid)) - goto bad_val; - } else if (!strcmp(opt, "gid")) { - gid = simple_strtoul(value, &rest, 0); - if (*rest) - goto bad_val; - ctx->gid = make_kgid(current_user_ns(), gid); + goto bad_value; + break; + case Opt_gid: + ctx->gid = make_kgid(current_user_ns(), result.uint_32); if (!gid_valid(ctx->gid)) - goto bad_val; -#ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE - } else if (!strcmp(opt, "huge")) { - int huge; - huge = shmem_parse_huge(value); - if (huge < 0) - goto bad_val; - if (!has_transparent_hugepage() && - huge != SHMEM_HUGE_NEVER) - goto bad_val; - ctx->huge = huge; + goto bad_value; + break; + case Opt_huge: + ctx->huge = result.uint_32; + if (ctx->huge != SHMEM_HUGE_NEVER && + !(IS_ENABLED(CONFIG_TRANSPARENT_HUGE_PAGECACHE) && + has_transparent_hugepage())) + goto unsupported_parameter; ctx->seen |= SHMEM_SEEN_HUGE; -#endif -#ifdef CONFIG_NUMA - } else if (!strcmp(opt, "mpol")) { - mpol_put(ctx->mpol); - ctx->mpol = NULL; - if (mpol_parse_str(value, &ctx->mpol)) - goto bad_val; -#endif - } else { - pr_err("tmpfs: Bad mount option %s\n", opt); - return -EINVAL; + break; + case Opt_mpol: + if (IS_ENABLED(CONFIG_NUMA)) { + mpol_put(ctx->mpol); + ctx->mpol = NULL; + if (mpol_parse_str(param->string, &ctx->mpol)) + goto bad_value; + break; + } + goto unsupported_parameter; } return 0; -bad_val: - pr_err("tmpfs: Bad value '%s' for mount option '%s'\n", - value, opt); - return -EINVAL; +unsupported_parameter: + return invalf(fc, "tmpfs: Unsupported parameter '%s'", param->key); +bad_value: + return invalf(fc, "tmpfs: Bad value for '%s'", param->key); } static int shmem_parse_options(char *options, struct shmem_options *ctx) { - char *this_char, *value; - while (options != NULL) { - this_char = options; + char *this_char = options; for (;;) { /* * NUL-terminate this option: unfortunately, @@ -3462,17 +3502,26 @@ static int shmem_parse_options(char *options, struct shmem_options *ctx) break; } } - if (!*this_char) - continue; - if ((value = strchr(this_char,'=')) != NULL) { - *value++ = 0; - } else { - pr_err("tmpfs: No value for mount option '%s'\n", - this_char); - goto error; + if (*this_char) { + char *value = strchr(this_char,'='); + struct fs_parameter param = { + .key = this_char, + .type = fs_value_is_string, + }; + int err; + + if (value) { + *value++ = '\0'; + param.size = strlen(value); + param.string = kstrdup(value, GFP_KERNEL); + if (!param.string) + goto error; + } + err = shmem_parse_one(ctx, ¶m); + kfree(param.string); + if (err) + goto error; } - if (shmem_parse_one(ctx, this_char, value) < 0) - goto error; } return 0;