148 lines
4.6 KiB
C
148 lines
4.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
|
/* Filesystem parameter description and parser
|
|
*
|
|
* Copyright (C) 2018 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*/
|
|
|
|
#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;
|
|
};
|
|
|
|
/*
|
|
* 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.
|
|
*
|
|
* Note that the fsparam_flag(), fsparam_string(), fsparam_u32(), ... macros
|
|
* should be used to generate elements of this type.
|
|
*/
|
|
struct fs_parameter_spec {
|
|
const char *name;
|
|
u8 opt; /* Option number (returned by fs_parse()) */
|
|
enum fs_parameter_type type:8; /* The desired parameter type */
|
|
unsigned short flags;
|
|
#define fs_param_v_optional 0x0001 /* The value is optional */
|
|
#define fs_param_neg_with_no 0x0002 /* "noxxx" is negative param */
|
|
#define fs_param_neg_with_empty 0x0004 /* "xxx=" is negative param */
|
|
#define fs_param_deprecated 0x0008 /* The param is deprecated */
|
|
};
|
|
|
|
struct fs_parameter_enum {
|
|
u8 opt; /* Option number (as fs_parameter_spec::opt) */
|
|
char name[14];
|
|
u8 value;
|
|
};
|
|
|
|
struct fs_parameter_description {
|
|
const char name[16]; /* Name for logging purposes */
|
|
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 {
|
|
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
|
|
|
|
/*
|
|
* Parameter type, name, index and flags element constructors. Use as:
|
|
*
|
|
* fsparam_xxxx("foo", Opt_foo)
|
|
*
|
|
* If existing helpers are not enough, direct use of __fsparam() would
|
|
* work, but any such case is probably a sign that new helper is needed.
|
|
* Helpers will remain stable; low-level implementation may change.
|
|
*/
|
|
#define __fsparam(TYPE, NAME, OPT, FLAGS) \
|
|
{ \
|
|
.name = NAME, \
|
|
.opt = OPT, \
|
|
.type = TYPE, \
|
|
.flags = FLAGS \
|
|
}
|
|
|
|
#define fsparam_flag(NAME, OPT) __fsparam(fs_param_is_flag, NAME, OPT, 0)
|
|
#define fsparam_flag_no(NAME, OPT) \
|
|
__fsparam(fs_param_is_flag, NAME, OPT, \
|
|
fs_param_neg_with_no)
|
|
#define fsparam_bool(NAME, OPT) __fsparam(fs_param_is_bool, NAME, OPT, 0)
|
|
#define fsparam_u32(NAME, OPT) __fsparam(fs_param_is_u32, NAME, OPT, 0)
|
|
#define fsparam_u32oct(NAME, OPT) \
|
|
__fsparam(fs_param_is_u32_octal, NAME, OPT, 0)
|
|
#define fsparam_u32hex(NAME, OPT) \
|
|
__fsparam(fs_param_is_u32_hex, NAME, OPT, 0)
|
|
#define fsparam_s32(NAME, OPT) __fsparam(fs_param_is_s32, NAME, OPT, 0)
|
|
#define fsparam_u64(NAME, OPT) __fsparam(fs_param_is_u64, NAME, OPT, 0)
|
|
#define fsparam_enum(NAME, OPT) __fsparam(fs_param_is_enum, NAME, OPT, 0)
|
|
#define fsparam_string(NAME, OPT) \
|
|
__fsparam(fs_param_is_string, NAME, OPT, 0)
|
|
#define fsparam_blob(NAME, OPT) __fsparam(fs_param_is_blob, NAME, OPT, 0)
|
|
#define fsparam_bdev(NAME, OPT) __fsparam(fs_param_is_blockdev, NAME, OPT, 0)
|
|
#define fsparam_path(NAME, OPT) __fsparam(fs_param_is_path, NAME, OPT, 0)
|
|
#define fsparam_fd(NAME, OPT) __fsparam(fs_param_is_fd, NAME, OPT, 0)
|
|
|
|
|
|
#endif /* _LINUX_FS_PARSER_H */
|