| /* Filesystem parameter description and parser |
| * |
| * Copyright (C) 2018 Red Hat, Inc. All Rights Reserved. |
| * Written by David Howells (dhowells@redhat.com) |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public Licence |
| * as published by the Free Software Foundation; either version |
| * 2 of the Licence, or (at your option) any later version. |
| */ |
| |
| #ifndef _LINUX_FS_PARSER_H |
| #define _LINUX_FS_PARSER_H |
| |
| #include <linux/fs_context.h> |
| |
| struct path; |
| |
| struct constant_table { |
| const char *name; |
| int value; |
| }; |
| |
| #define fsconfig_key_removed 0xff /* Parameter name is no longer valid */ |
| |
| /* |
| * The type of parameter expected. |
| */ |
| enum fs_parameter_type { |
| __fs_param_wasnt_defined, |
| fs_param_is_flag, |
| fs_param_is_bool, |
| fs_param_is_u32, |
| fs_param_is_u32_octal, |
| fs_param_is_u32_hex, |
| fs_param_is_s32, |
| fs_param_is_u64, |
| fs_param_is_enum, |
| fs_param_is_string, |
| fs_param_is_blob, |
| fs_param_is_blockdev, |
| fs_param_is_path, |
| fs_param_is_fd, |
| nr__fs_parameter_type, |
| }; |
| |
| /* |
| * Specification of the type of value a parameter wants. |
| */ |
| struct fs_parameter_spec { |
| enum fs_parameter_type type:8; /* The desired parameter type */ |
| u8 flags; |
| #define fs_param_v_optional 0x01 /* The value is optional */ |
| #define fs_param_neg_with_no 0x02 /* "noxxx" is negative param */ |
| #define fs_param_neg_with_empty 0x04 /* "xxx=" is negative param */ |
| #define fs_param_deprecated 0x08 /* The param is deprecated */ |
| }; |
| |
| struct fs_parameter_enum { |
| u8 param_id; |
| char name[14]; |
| u8 value; |
| }; |
| |
| struct fs_parameter_description { |
| const char name[16]; /* Name for logging purposes */ |
| u8 nr_params; /* Number of parameter IDs */ |
| u8 nr_alt_keys; /* Number of alt_keys[] */ |
| u8 nr_enums; /* Number of enum value names */ |
| u8 source_param; /* Index of source parameter */ |
| bool no_source; /* Set if no source is expected */ |
| const char *const *keys; /* Sorted list of key names, one per nr_params */ |
| const struct constant_table *alt_keys; /* Sorted list of alternate key names */ |
| const struct fs_parameter_spec *specs; /* List of param specifications */ |
| const struct fs_parameter_enum *enums; /* Enum values */ |
| }; |
| |
| /* |
| * Result of parse. |
| */ |
| struct fs_parse_result { |
| struct fs_parameter_spec t; |
| u8 key; /* Looked up key ID */ |
| bool negated; /* T if param was "noxxx" */ |
| bool has_value; /* T if value supplied to param */ |
| union { |
| bool boolean; /* For spec_bool */ |
| int int_32; /* For spec_s32/spec_enum */ |
| unsigned int uint_32; /* For spec_u32{,_octal,_hex}/spec_enum */ |
| u64 uint_64; /* For spec_u64 */ |
| }; |
| }; |
| |
| extern int fs_parse(struct fs_context *fc, |
| const struct fs_parameter_description *desc, |
| struct fs_parameter *value, |
| struct fs_parse_result *result); |
| extern int fs_lookup_param(struct fs_context *fc, |
| struct fs_parameter *param, |
| bool want_bdev, |
| struct path *_path); |
| |
| extern int __lookup_constant(const struct constant_table tbl[], size_t tbl_size, |
| const char *name, int not_found); |
| #define lookup_constant(t, n, nf) __lookup_constant(t, ARRAY_SIZE(t), (n), (nf)) |
| |
| #ifdef CONFIG_VALIDATE_FS_PARSER |
| extern bool validate_constant_table(const struct constant_table *tbl, size_t tbl_size, |
| int low, int high, int special); |
| extern bool fs_validate_description(const struct fs_parameter_description *desc); |
| #else |
| static inline bool validate_constant_table(const struct constant_table *tbl, size_t tbl_size, |
| int low, int high, int special) |
| { return true; } |
| static inline bool fs_validate_description(const struct fs_parameter_description *desc) |
| { return true; } |
| #endif |
| |
| #endif /* _LINUX_FS_PARSER_H */ |