root/include/linux/module.h

INCLUDED FROM

DEFINITIONS

1. enforce_signed_modules
2. module_is_live
3. within_module_core
4. within_module_init
5. within_module
6. try_module_get
7. module_put
8. __module_get
9. search_module_extables
10. __module_address
11. __module_text_address
12. is_module_address
13. is_module_percpu_address
14. is_module_text_address
15. __module_get
16. try_module_get
17. module_put
18. module_address_lookup
19. lookup_module_symbol_name
20. lookup_module_symbol_attrs
21. module_get_kallsym
22. module_kallsyms_lookup_name
23. module_kallsyms_on_each_symbol
24. register_module_notifier
25. unregister_module_notifier
26. print_modules
27. secure_modules
28. set_all_modules_text_rw
29. set_all_modules_text_ro
30. module_bug_finalize
31. module_bug_cleanup

#ifndef _LINUX_MODULE_H
#define _LINUX_MODULE_H
/*
 * Dynamic loading of modules into the kernel.
 *
 * Rewritten by Richard Henderson <rth@tamu.edu> Dec 1996
 * Rewritten again by Rusty Russell, 2002
 */
#include <linux/list.h>
#include <linux/stat.h>
#include <linux/compiler.h>
#include <linux/cache.h>
#include <linux/kmod.h>
#include <linux/elf.h>
#include <linux/stringify.h>
#include <linux/kobject.h>
#include <linux/moduleparam.h>
#include <linux/jump_label.h>
#include <linux/export.h>

#include <linux/percpu.h>
#include <asm/module.h>

/* In stripped ARM and x86-64 modules, ~ is surprisingly rare. */
#define MODULE_SIG_STRING "~Module signature appended~\n"

/* Not Yet Implemented */
#define MODULE_SUPPORTED_DEVICE(name)

#define MODULE_NAME_LEN MAX_PARAM_PREFIX_LEN

struct modversion_info {
        unsigned long crc;
        char name[MODULE_NAME_LEN];
};

struct module;

struct module_kobject {
        struct kobject kobj;
        struct module *mod;
        struct kobject *drivers_dir;
        struct module_param_attrs *mp;
        struct completion *kobj_completion;
};

struct module_attribute {
        struct attribute attr;
        ssize_t (*show)(struct module_attribute *, struct module_kobject *,
                        char *);
        ssize_t (*store)(struct module_attribute *, struct module_kobject *,
                         const char *, size_t count);
        void (*setup)(struct module *, const char *);
        int (*test)(struct module *);
        void (*free)(struct module *);
};

struct module_version_attribute {
        struct module_attribute mattr;
        const char *module_name;
        const char *version;
} __attribute__ ((__aligned__(sizeof(void *))));

extern ssize_t __modver_version_show(struct module_attribute *,
                                     struct module_kobject *, char *);

extern struct module_attribute module_uevent;

/* These are either module local, or the kernel's dummy ones. */
extern int init_module(void);
extern void cleanup_module(void);

/* Archs provide a method of finding the correct exception table. */
struct exception_table_entry;

const struct exception_table_entry *
search_extable(const struct exception_table_entry *first,
               const struct exception_table_entry *last,
               unsigned long value);
void sort_extable(struct exception_table_entry *start,
                  struct exception_table_entry *finish);
void sort_main_extable(void);
void trim_init_extable(struct module *m);

/* Generic info of form tag = "info" */
#define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)

/* For userspace: you can also call me... */
#define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)

/* Soft module dependencies. See man modprobe.d for details.
 * Example: MODULE_SOFTDEP("pre: module-foo module-bar post: module-baz")
 */
#define MODULE_SOFTDEP(_softdep) MODULE_INFO(softdep, _softdep)

/*
 * The following license idents are currently accepted as indicating free
 * software modules
 *
 *      "GPL"                           [GNU Public License v2 or later]
 *      "GPL v2"                        [GNU Public License v2]
 *      "GPL and additional rights"     [GNU Public License v2 rights and more]
 *      "Dual BSD/GPL"                  [GNU Public License v2
 *                                       or BSD license choice]
 *      "Dual MIT/GPL"                  [GNU Public License v2
 *                                       or MIT license choice]
 *      "Dual MPL/GPL"                  [GNU Public License v2
 *                                       or Mozilla license choice]
 *
 * The following other idents are available
 *
 *      "Proprietary"                   [Non free products]
 *
 * There are dual licensed components, but when running with Linux it is the
 * GPL that is relevant so this is a non issue. Similarly LGPL linked with GPL
 * is a GPL combined work.
 *
 * This exists for several reasons
 * 1.   So modinfo can show license info for users wanting to vet their setup
 *      is free
 * 2.   So the community can ignore bug reports including proprietary modules
 * 3.   So vendors can do likewise based on their own policies
 */
#define MODULE_LICENSE(_license) MODULE_INFO(license, _license)

/*
 * Author(s), use "Name <email>" or just "Name", for multiple
 * authors use multiple MODULE_AUTHOR() statements/lines.
 */
#define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)

/* What your module does. */
#define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)

#ifdef MODULE
/* Creates an alias so file2alias.c can find device table. */
#define MODULE_DEVICE_TABLE(type, name)                                 \
  extern const struct type##_device_id __mod_##type##__##name##_device_table \
  __attribute__ ((unused, alias(__stringify(name))))
#else  /* !MODULE */
#define MODULE_DEVICE_TABLE(type, name)
#endif

/* Version of form [<epoch>:]<version>[-<extra-version>].
 * Or for CVS/RCS ID version, everything but the number is stripped.
 * <epoch>: A (small) unsigned integer which allows you to start versions
 * anew. If not mentioned, it's zero.  eg. "2:1.0" is after
 * "1:2.0".

 * <version>: The <version> may contain only alphanumerics and the
 * character `.'.  Ordered by numeric sort for numeric parts,
 * ascii sort for ascii parts (as per RPM or DEB algorithm).

 * <extraversion>: Like <version>, but inserted for local
 * customizations, eg "rh3" or "rusty1".

 * Using this automatically adds a checksum of the .c files and the
 * local headers in "srcversion".
 */

#if defined(MODULE) || !defined(CONFIG_SYSFS)
#define MODULE_VERSION(_version) MODULE_INFO(version, _version)
#else
#define MODULE_VERSION(_version)                                        \
        static struct module_version_attribute ___modver_attr = {       \
                .mattr  = {                                             \
                        .attr   = {                                     \
                                .name   = "version",                    \
                                .mode   = S_IRUGO,                      \
                        },                                              \
                        .show   = __modver_version_show,                \
                },                                                      \
                .module_name    = KBUILD_MODNAME,                       \
                .version        = _version,                             \
        };                                                              \
        static const struct module_version_attribute                    \
        __used __attribute__ ((__section__ ("__modver")))               \
        * __moduleparam_const __modver_attr = &___modver_attr
#endif

/* Optional firmware file (or files) needed by the module
 * format is simply firmware file name.  Multiple firmware
 * files require multiple MODULE_FIRMWARE() specifiers */
#define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware)

/* Given an address, look for it in the exception tables */
const struct exception_table_entry *search_exception_tables(unsigned long add);

struct notifier_block;

#ifdef CONFIG_MODULE_SIG
extern void enforce_signed_modules(void);
#else
static inline void enforce_signed_modules(void) {};
#endif

#ifdef CONFIG_MODULES

extern int modules_disabled; /* for sysctl */
/* Get/put a kernel symbol (calls must be symmetric) */
void *__symbol_get(const char *symbol);
void *__symbol_get_gpl(const char *symbol);
#define symbol_get(x) ((typeof(&x))(__symbol_get(VMLINUX_SYMBOL_STR(x))))

/* modules using other modules: kdb wants to see this. */
struct module_use {
        struct list_head source_list;
        struct list_head target_list;
        struct module *source, *target;
};

enum module_state {
        MODULE_STATE_LIVE,      /* Normal state. */
        MODULE_STATE_COMING,    /* Full formed, running module_init. */
        MODULE_STATE_GOING,     /* Going away. */
        MODULE_STATE_UNFORMED,  /* Still setting it up. */
};

/**
 * struct module_ref - per cpu module reference counts
 * @incs: number of module get on this cpu
 * @decs: number of module put on this cpu
 *
 * We force an alignment on 8 or 16 bytes, so that alloc_percpu()
 * put @incs/@decs in same cache line, with no extra memory cost,
 * since alloc_percpu() is fine grained.
 */
struct module_ref {
        unsigned long incs;
        unsigned long decs;
} __attribute((aligned(2 * sizeof(unsigned long))));

struct module {
        enum module_state state;

        /* Member of list of modules */
        struct list_head list;

        /* Unique handle for this module */
        char name[MODULE_NAME_LEN];

        /* Sysfs stuff. */
        struct module_kobject mkobj;
        struct module_attribute *modinfo_attrs;
        const char *version;
        const char *srcversion;
        struct kobject *holders_dir;

        /* Exported symbols */
        const struct kernel_symbol *syms;
        const unsigned long *crcs;
        unsigned int num_syms;

        /* Kernel parameters. */
        struct kernel_param *kp;
        unsigned int num_kp;

        /* GPL-only exported symbols. */
        unsigned int num_gpl_syms;
        const struct kernel_symbol *gpl_syms;
        const unsigned long *gpl_crcs;

#ifdef CONFIG_UNUSED_SYMBOLS
        /* unused exported symbols. */
        const struct kernel_symbol *unused_syms;
        const unsigned long *unused_crcs;
        unsigned int num_unused_syms;

        /* GPL-only, unused exported symbols. */
        unsigned int num_unused_gpl_syms;
        const struct kernel_symbol *unused_gpl_syms;
        const unsigned long *unused_gpl_crcs;
#endif

#ifdef CONFIG_MODULE_SIG
        /* Signature was verified. */
        bool sig_ok;
#endif

        /* symbols that will be GPL-only in the near future. */
        const struct kernel_symbol *gpl_future_syms;
        const unsigned long *gpl_future_crcs;
        unsigned int num_gpl_future_syms;

        /* Exception table */
        unsigned int num_exentries;
        struct exception_table_entry *extable;

        /* Startup function. */
        int (*init)(void);

        /* If this is non-NULL, vfree after init() returns */
        void *module_init;

        /* Here is the actual code + data, vfree'd on unload. */
        void *module_core;

        /* Here are the sizes of the init and core sections */
        unsigned int init_size, core_size;

        /* The size of the executable code in each section.  */
        unsigned int init_text_size, core_text_size;

        /* Size of RO sections of the module (text+rodata) */
        unsigned int init_ro_size, core_ro_size;

        /* Arch-specific module values */
        struct mod_arch_specific arch;

        unsigned int taints;    /* same bits as kernel:tainted */

#ifdef CONFIG_GENERIC_BUG
        /* Support for BUG */
        unsigned num_bugs;
        struct list_head bug_list;
        struct bug_entry *bug_table;
#endif

#ifdef CONFIG_KALLSYMS
        /*
         * We keep the symbol and string tables for kallsyms.
         * The core_* fields below are temporary, loader-only (they
         * could really be discarded after module init).
         */
        Elf_Sym *symtab, *core_symtab;
        unsigned int num_symtab, core_num_syms;
        char *strtab, *core_strtab;

        /* Section attributes */
        struct module_sect_attrs *sect_attrs;

        /* Notes attributes */
        struct module_notes_attrs *notes_attrs;
#endif

        /* The command line arguments (may be mangled).  People like
           keeping pointers to this stuff */
        char *args;

#ifdef CONFIG_SMP
        /* Per-cpu data. */
        void __percpu *percpu;
        unsigned int percpu_size;
#endif

#ifdef CONFIG_TRACEPOINTS
        unsigned int num_tracepoints;
        struct tracepoint * const *tracepoints_ptrs;
#endif
#ifdef HAVE_JUMP_LABEL
        struct jump_entry *jump_entries;
        unsigned int num_jump_entries;
#endif
#ifdef CONFIG_TRACING
        unsigned int num_trace_bprintk_fmt;
        const char **trace_bprintk_fmt_start;
#endif
#ifdef CONFIG_EVENT_TRACING
        struct ftrace_event_call **trace_events;
        unsigned int num_trace_events;
#endif
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
        unsigned int num_ftrace_callsites;
        unsigned long *ftrace_callsites;
#endif

#ifdef CONFIG_MODULE_UNLOAD
        /* What modules depend on me? */
        struct list_head source_list;
        /* What modules do I depend on? */
        struct list_head target_list;

        /* Destruction function. */
        void (*exit)(void);

        struct module_ref __percpu *refptr;
#endif

#ifdef CONFIG_CONSTRUCTORS
        /* Constructor functions. */
        ctor_fn_t *ctors;
        unsigned int num_ctors;
#endif
};
#ifndef MODULE_ARCH_INIT
#define MODULE_ARCH_INIT {}
#endif

extern struct mutex module_mutex;

/* FIXME: It'd be nice to isolate modules during init, too, so they
   aren't used before they (may) fail.  But presently too much code
   (IDE & SCSI) require entry into the module during init.*/
static inline int module_is_live(struct module *mod)
{
        return mod->state != MODULE_STATE_GOING;
}

struct module *__module_text_address(unsigned long addr);
struct module *__module_address(unsigned long addr);
bool is_module_address(unsigned long addr);
bool is_module_percpu_address(unsigned long addr);
bool is_module_text_address(unsigned long addr);

static inline bool within_module_core(unsigned long addr,
                                      const struct module *mod)
{
        return (unsigned long)mod->module_core <= addr &&
               addr < (unsigned long)mod->module_core + mod->core_size;
}

static inline bool within_module_init(unsigned long addr,
                                      const struct module *mod)
{
        return (unsigned long)mod->module_init <= addr &&
               addr < (unsigned long)mod->module_init + mod->init_size;
}

static inline bool within_module(unsigned long addr, const struct module *mod)
{
        return within_module_init(addr, mod) || within_module_core(addr, mod);
}

/* Search for module by name: must hold module_mutex. */
struct module *find_module(const char *name);

struct symsearch {
        const struct kernel_symbol *start, *stop;
        const unsigned long *crcs;
        enum {
                NOT_GPL_ONLY,
                GPL_ONLY,
                WILL_BE_GPL_ONLY,
        } licence;
        bool unused;
};

/* Search for an exported symbol by name. */
const struct kernel_symbol *find_symbol(const char *name,
                                        struct module **owner,
                                        const unsigned long **crc,
                                        bool gplok,
                                        bool warn);

/* Walk the exported symbol table */
bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
                                    struct module *owner,
                                    void *data), void *data);

/* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
   symnum out of range. */
int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
                        char *name, char *module_name, int *exported);

/* Look for this name: can be of form module:name. */
unsigned long module_kallsyms_lookup_name(const char *name);

int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
                                             struct module *, unsigned long),
                                   void *data);

extern void __module_put_and_exit(struct module *mod, long code)
        __attribute__((noreturn));
#define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code)

#ifdef CONFIG_MODULE_UNLOAD
unsigned long module_refcount(struct module *mod);
void __symbol_put(const char *symbol);
#define symbol_put(x) __symbol_put(VMLINUX_SYMBOL_STR(x))
void symbol_put_addr(void *addr);

/* Sometimes we know we already have a refcount, and it's easier not
   to handle the error case (which only happens with rmmod --wait). */
extern void __module_get(struct module *module);

/* This is the Right Way to get a module: if it fails, it's being removed,
 * so pretend it's not there. */
extern bool try_module_get(struct module *module);

extern void module_put(struct module *module);

#else /*!CONFIG_MODULE_UNLOAD*/
static inline int try_module_get(struct module *module)
{
        return !module || module_is_live(module);
}
static inline void module_put(struct module *module)
{
}
static inline void __module_get(struct module *module)
{
}
#define symbol_put(x) do { } while (0)
#define symbol_put_addr(p) do { } while (0)

#endif /* CONFIG_MODULE_UNLOAD */
int ref_module(struct module *a, struct module *b);

/* This is a #define so the string doesn't get put in every .o file */
#define module_name(mod)                        \
({                                              \
        struct module *__mod = (mod);           \
        __mod ? __mod->name : "kernel";         \
})

/* For kallsyms to ask for address resolution.  namebuf should be at
 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
 * found, otherwise NULL. */
const char *module_address_lookup(unsigned long addr,
                            unsigned long *symbolsize,
                            unsigned long *offset,
                            char **modname,
                            char *namebuf);
int lookup_module_symbol_name(unsigned long addr, char *symname);
int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);

/* For extable.c to search modules' exception tables. */
const struct exception_table_entry *search_module_extables(unsigned long addr);

int register_module_notifier(struct notifier_block *nb);
int unregister_module_notifier(struct notifier_block *nb);

extern void print_modules(void);

extern bool secure_modules(void);

#else /* !CONFIG_MODULES... */

/* Given an address, look for it in the exception tables. */
static inline const struct exception_table_entry *
search_module_extables(unsigned long addr)
{
        return NULL;
}

static inline struct module *__module_address(unsigned long addr)
{
        return NULL;
}

static inline struct module *__module_text_address(unsigned long addr)
{
        return NULL;
}

static inline bool is_module_address(unsigned long addr)
{
        return false;
}

static inline bool is_module_percpu_address(unsigned long addr)
{
        return false;
}

static inline bool is_module_text_address(unsigned long addr)
{
        return false;
}

/* Get/put a kernel symbol (calls should be symmetric) */
#define symbol_get(x) ({ extern typeof(x) x __attribute__((weak)); &(x); })
#define symbol_put(x) do { } while (0)
#define symbol_put_addr(x) do { } while (0)

static inline void __module_get(struct module *module)
{
}

static inline int try_module_get(struct module *module)
{
        return 1;
}

static inline void module_put(struct module *module)
{
}

#define module_name(mod) "kernel"

/* For kallsyms to ask for address resolution.  NULL means not found. */
static inline const char *module_address_lookup(unsigned long addr,
                                          unsigned long *symbolsize,
                                          unsigned long *offset,
                                          char **modname,
                                          char *namebuf)
{
        return NULL;
}

static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
{
        return -ERANGE;
}

static inline int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
{
        return -ERANGE;
}

static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
                                        char *type, char *name,
                                        char *module_name, int *exported)
{
        return -ERANGE;
}

static inline unsigned long module_kallsyms_lookup_name(const char *name)
{
        return 0;
}

static inline int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
                                                           struct module *,
                                                           unsigned long),
                                                 void *data)
{
        return 0;
}

static inline int register_module_notifier(struct notifier_block *nb)
{
        /* no events will happen anyway, so this can always succeed */
        return 0;
}

static inline int unregister_module_notifier(struct notifier_block *nb)
{
        return 0;
}

#define module_put_and_exit(code) do_exit(code)

static inline void print_modules(void)
{
}

static inline bool secure_modules(void)
{
        return false;
}
#endif /* CONFIG_MODULES */

#ifdef CONFIG_SYSFS
extern struct kset *module_kset;
extern struct kobj_type module_ktype;
extern int module_sysfs_initialized;
#endif /* CONFIG_SYSFS */

#define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)

/* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */

#define __MODULE_STRING(x) __stringify(x)

#ifdef CONFIG_DEBUG_SET_MODULE_RONX
extern void set_all_modules_text_rw(void);
extern void set_all_modules_text_ro(void);
#else
static inline void set_all_modules_text_rw(void) { }
static inline void set_all_modules_text_ro(void) { }
#endif

#ifdef CONFIG_GENERIC_BUG
void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
                         struct module *);
void module_bug_cleanup(struct module *);

#else   /* !CONFIG_GENERIC_BUG */

static inline void module_bug_finalize(const Elf_Ehdr *hdr,
                                        const Elf_Shdr *sechdrs,
                                        struct module *mod)
{
}
static inline void module_bug_cleanup(struct module *mod) {}
#endif  /* CONFIG_GENERIC_BUG */

#endif /* _LINUX_MODULE_H */