kernel_optimize_test/include/linux/module.h
Masami Hiramatsu a06f6211ef module: add within_module_core() and within_module_init()
This series of patches allows kprobes to probe module's __init and __exit
functions.  This means, you can probe driver initialization and
terminating.

Currently, kprobes can't probe __init function because these functions are
freed after module initialization.  And it also can't probe module __exit
functions because kprobe increments reference count of target module and
user can't unload it.  this means __exit functions never be called unless
removing probes from the module.

To solve both cases, this series of patches introduces GONE flag and sets
it when the target code is freed(for this purpose, kprobes hooks
MODULE_STATE_* events).  This also removes refcount incrementing for
allowing user to unload target module.  Users can check which probes are
GONE by debugfs interface.  For taking timing of freeing module's .init
text, these also include a patch which adds module's notifier of
MODULE_STATE_LIVE event.

This patch:

Add within_module_core() and within_module_init() for checking whether an
address is in the module .init.text section or .text section, and replace
within() local inline functions in kernel/module.c with them.

kprobes uses these functions to check where the kprobe is inserted.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:20 -08:00

634 lines
17 KiB
C

#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/marker.h>
#include <linux/tracepoint.h>
#include <asm/local.h>
#include <asm/module.h>
/* Not Yet Implemented */
#define MODULE_SUPPORTED_DEVICE(name)
/* some toolchains uses a `_' prefix for all user symbols */
#ifndef MODULE_SYMBOL_PREFIX
#define MODULE_SYMBOL_PREFIX ""
#endif
#define MODULE_NAME_LEN MAX_PARAM_PREFIX_LEN
struct kernel_symbol
{
unsigned long value;
const char *name;
};
struct modversion_info
{
unsigned long crc;
char name[MODULE_NAME_LEN];
};
struct module;
struct module_attribute {
struct attribute attr;
ssize_t (*show)(struct module_attribute *, struct module *, char *);
ssize_t (*store)(struct module_attribute *, struct module *,
const char *, size_t count);
void (*setup)(struct module *, const char *);
int (*test)(struct module *);
void (*free)(struct module *);
};
struct module_kobject
{
struct kobject kobj;
struct module *mod;
struct kobject *drivers_dir;
struct module_param_attrs *mp;
};
/* 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);
#ifdef MODULE
#define MODULE_GENERIC_TABLE(gtype,name) \
extern const struct gtype##_id __mod_##gtype##_table \
__attribute__ ((unused, alias(__stringify(name))))
extern struct module __this_module;
#define THIS_MODULE (&__this_module)
#else /* !MODULE */
#define MODULE_GENERIC_TABLE(gtype,name)
#define THIS_MODULE ((struct module *)0)
#endif
/* 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)
/*
* 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, ideally of form NAME[, NAME]*[ and NAME] */
#define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
/* What your module does. */
#define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
/* One for each parameter, describing how to use it. Some files do
multiple of these per line, so can't just use MODULE_INFO. */
#define MODULE_PARM_DESC(_parm, desc) \
__MODULE_INFO(parm, _parm, #_parm ":" desc)
#define MODULE_DEVICE_TABLE(type,name) \
MODULE_GENERIC_TABLE(type##_device,name)
/* 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".
*/
#define MODULE_VERSION(_version) MODULE_INFO(version, _version)
/* 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_MODULES
/* 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(MODULE_SYMBOL_PREFIX #x)))
#ifndef __GENKSYMS__
#ifdef CONFIG_MODVERSIONS
/* Mark the CRC weak since genksyms apparently decides not to
* generate a checksums for some symbols */
#define __CRC_SYMBOL(sym, sec) \
extern void *__crc_##sym __attribute__((weak)); \
static const unsigned long __kcrctab_##sym \
__used \
__attribute__((section("__kcrctab" sec), unused)) \
= (unsigned long) &__crc_##sym;
#else
#define __CRC_SYMBOL(sym, sec)
#endif
/* For every exported symbol, place a struct in the __ksymtab section */
#define __EXPORT_SYMBOL(sym, sec) \
extern typeof(sym) sym; \
__CRC_SYMBOL(sym, sec) \
static const char __kstrtab_##sym[] \
__attribute__((section("__ksymtab_strings"), aligned(1))) \
= MODULE_SYMBOL_PREFIX #sym; \
static const struct kernel_symbol __ksymtab_##sym \
__used \
__attribute__((section("__ksymtab" sec), unused)) \
= { (unsigned long)&sym, __kstrtab_##sym }
#define EXPORT_SYMBOL(sym) \
__EXPORT_SYMBOL(sym, "")
#define EXPORT_SYMBOL_GPL(sym) \
__EXPORT_SYMBOL(sym, "_gpl")
#define EXPORT_SYMBOL_GPL_FUTURE(sym) \
__EXPORT_SYMBOL(sym, "_gpl_future")
#ifdef CONFIG_UNUSED_SYMBOLS
#define EXPORT_UNUSED_SYMBOL(sym) __EXPORT_SYMBOL(sym, "_unused")
#define EXPORT_UNUSED_SYMBOL_GPL(sym) __EXPORT_SYMBOL(sym, "_unused_gpl")
#else
#define EXPORT_UNUSED_SYMBOL(sym)
#define EXPORT_UNUSED_SYMBOL_GPL(sym)
#endif
#endif
struct module_ref
{
local_t count;
} ____cacheline_aligned;
enum module_state
{
MODULE_STATE_LIVE,
MODULE_STATE_COMING,
MODULE_STATE_GOING,
};
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;
/* 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
/* 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;
/* 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. */
Elf_Sym *symtab;
unsigned int num_symtab;
char *strtab;
/* Section attributes */
struct module_sect_attrs *sect_attrs;
/* Notes attributes */
struct module_notes_attrs *notes_attrs;
#endif
/* Per-cpu data. */
void *percpu;
/* The command line arguments (may be mangled). People like
keeping pointers to this stuff */
char *args;
#ifdef CONFIG_MARKERS
struct marker *markers;
unsigned int num_markers;
#endif
#ifdef CONFIG_TRACEPOINTS
struct tracepoint *tracepoints;
unsigned int num_tracepoints;
#endif
#ifdef CONFIG_MODULE_UNLOAD
/* What modules depend on me? */
struct list_head modules_which_use_me;
/* Who is waiting for us to be unloaded */
struct task_struct *waiter;
/* Destruction function. */
void (*exit)(void);
/* Reference counts */
struct module_ref ref[NR_CPUS];
#endif
};
#ifndef MODULE_ARCH_INIT
#define MODULE_ARCH_INIT {}
#endif
/* 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;
}
/* Is this address in a module? (second is with no locks, for oops) */
struct module *module_text_address(unsigned long addr);
struct module *__module_text_address(unsigned long addr);
int is_module_address(unsigned long addr);
static inline int within_module_core(unsigned long addr, struct module *mod)
{
return (unsigned long)mod->module_core <= addr &&
addr < (unsigned long)mod->module_core + mod->core_size;
}
static inline int within_module_init(unsigned long addr, struct module *mod)
{
return (unsigned long)mod->module_init <= addr &&
addr < (unsigned long)mod->module_init + mod->init_size;
}
/* 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);
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 int module_refcount(struct module *mod);
void __symbol_put(const char *symbol);
#define symbol_put(x) __symbol_put(MODULE_SYMBOL_PREFIX #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). */
static inline void __module_get(struct module *module)
{
if (module) {
BUG_ON(module_refcount(module) == 0);
local_inc(&module->ref[get_cpu()].count);
put_cpu();
}
}
static inline int try_module_get(struct module *module)
{
int ret = 1;
if (module) {
unsigned int cpu = get_cpu();
if (likely(module_is_live(module)))
local_inc(&module->ref[cpu].count);
else
ret = 0;
put_cpu();
}
return ret;
}
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 */
/* 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 void module_update_markers(void);
extern void module_update_tracepoints(void);
extern int module_get_iter_tracepoints(struct tracepoint_iter *iter);
#else /* !CONFIG_MODULES... */
#define EXPORT_SYMBOL(sym)
#define EXPORT_SYMBOL_GPL(sym)
#define EXPORT_SYMBOL_GPL_FUTURE(sym)
#define EXPORT_UNUSED_SYMBOL(sym)
#define EXPORT_UNUSED_SYMBOL_GPL(sym)
/* 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;
}
/* Is this address in a module? */
static inline struct module *module_text_address(unsigned long addr)
{
return NULL;
}
/* Is this address in a module? (don't take a lock, we're oopsing) */
static inline struct module *__module_text_address(unsigned long addr)
{
return NULL;
}
static inline int is_module_address(unsigned long addr)
{
return 0;
}
/* 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 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 void module_update_markers(void)
{
}
static inline void module_update_tracepoints(void)
{
}
static inline int module_get_iter_tracepoints(struct tracepoint_iter *iter)
{
return 0;
}
#endif /* CONFIG_MODULES */
struct device_driver;
#ifdef CONFIG_SYSFS
struct module;
extern struct kset *module_kset;
extern struct kobj_type module_ktype;
extern int module_sysfs_initialized;
int mod_sysfs_init(struct module *mod);
int mod_sysfs_setup(struct module *mod,
struct kernel_param *kparam,
unsigned int num_params);
int module_add_modinfo_attrs(struct module *mod);
void module_remove_modinfo_attrs(struct module *mod);
#else /* !CONFIG_SYSFS */
static inline int mod_sysfs_init(struct module *mod)
{
return 0;
}
static inline int mod_sysfs_setup(struct module *mod,
struct kernel_param *kparam,
unsigned int num_params)
{
return 0;
}
static inline int module_add_modinfo_attrs(struct module *mod)
{
return 0;
}
static inline void module_remove_modinfo_attrs(struct module *mod)
{ }
#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)
#endif /* _LINUX_MODULE_H */