freebsd-dev/sys/sys/module.h
Konstantin Belousov 78ae4338a2 Add macro DECLARE_MODULE_TIED to denote a module as requiring the
kernel of exactly the same __FreeBSD_version as the headers module was
compiled against.

Mark our in-tree ABI emulators with DECLARE_MODULE_TIED. The modules
use kernel interfaces that the Release Engineering Team feel are not
stable enough to guarantee they will not change during the life cycle
of a STABLE branch. In particular, the layout of struct sysentvec is
declared to be not part of the STABLE KBI.

Discussed with:	bz, rwatson
Approved by:	re (bz, kensmith)
MFC after:	2 weeks
2010-10-12 09:18:17 +00:00

219 lines
6.3 KiB
C

/*-
* Copyright (c) 1997 Doug Rabson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _SYS_MODULE_H_
#define _SYS_MODULE_H_
/*
* Module metadata types
*/
#define MDT_DEPEND 1 /* argument is a module name */
#define MDT_MODULE 2 /* module declaration */
#define MDT_VERSION 3 /* module version(s) */
#define MDT_STRUCT_VERSION 1 /* version of metadata structure */
#define MDT_SETNAME "modmetadata_set"
typedef enum modeventtype {
MOD_LOAD,
MOD_UNLOAD,
MOD_SHUTDOWN,
MOD_QUIESCE
} modeventtype_t;
typedef struct module *module_t;
typedef int (*modeventhand_t)(module_t, int /* modeventtype_t */, void *);
/*
* Struct for registering modules statically via SYSINIT.
*/
typedef struct moduledata {
const char *name; /* module name */
modeventhand_t evhand; /* event handler */
void *priv; /* extra data */
} moduledata_t;
/*
* A module can use this to report module specific data to the user via
* kldstat(2).
*/
typedef union modspecific {
int intval;
u_int uintval;
long longval;
u_long ulongval;
} modspecific_t;
/*
* Module dependency declarartion
*/
struct mod_depend {
int md_ver_minimum;
int md_ver_preferred;
int md_ver_maximum;
};
/*
* Module version declaration
*/
struct mod_version {
int mv_version;
};
struct mod_metadata {
int md_version; /* structure version MDTV_* */
int md_type; /* type of entry MDT_* */
void *md_data; /* specific data */
const char *md_cval; /* common string label */
};
#ifdef _KERNEL
#include <sys/linker_set.h>
#define MODULE_METADATA(uniquifier, type, data, cval) \
static struct mod_metadata _mod_metadata##uniquifier = { \
MDT_STRUCT_VERSION, \
type, \
data, \
cval \
}; \
DATA_SET(modmetadata_set, _mod_metadata##uniquifier)
#define MODULE_DEPEND(module, mdepend, vmin, vpref, vmax) \
static struct mod_depend _##module##_depend_on_##mdepend = { \
vmin, \
vpref, \
vmax \
}; \
MODULE_METADATA(_md_##module##_on_##mdepend, MDT_DEPEND, \
&_##module##_depend_on_##mdepend, #mdepend)
/*
* Every kernel has a 'kernel' module with the version set to
* __FreeBSD_version. We embed a MODULE_DEPEND() inside every module
* that depends on the 'kernel' module. It uses the current value of
* __FreeBSD_version as the minimum and preferred versions. For the
* maximum version it rounds the version up to the end of its branch
* (i.e. M99999 for M.x). This allows a module built on M.x to work
* on M.y systems where y >= x, but fail on M.z systems where z < x.
*/
#define MODULE_KERNEL_MAXVER (roundup(__FreeBSD_version, 100000) - 1)
#define DECLARE_MODULE_WITH_MAXVER(name, data, sub, order, maxver) \
MODULE_DEPEND(name, kernel, __FreeBSD_version, \
__FreeBSD_version, maxver); \
MODULE_METADATA(_md_##name, MDT_MODULE, &data, #name); \
SYSINIT(name##module, sub, order, module_register_init, &data); \
struct __hack
#define DECLARE_MODULE(name, data, sub, order) \
DECLARE_MODULE_WITH_MAXVER(name, data, sub, order, MODULE_KERNEL_MAXVER)
/*
* The module declared with DECLARE_MODULE_TIED can only be loaded
* into the kernel with exactly the same __FreeBSD_version.
*
* Use it for modules that use kernel interfaces that are not stable
* even on STABLE/X branches.
*/
#define DECLARE_MODULE_TIED(name, data, sub, order) \
DECLARE_MODULE_WITH_MAXVER(name, data, sub, order, __FreeBSD_version)
#define MODULE_VERSION(module, version) \
static struct mod_version _##module##_version = { \
version \
}; \
MODULE_METADATA(_##module##_version, MDT_VERSION, \
&_##module##_version, #module)
extern struct sx modules_sx;
#define MOD_XLOCK sx_xlock(&modules_sx)
#define MOD_SLOCK sx_slock(&modules_sx)
#define MOD_XUNLOCK sx_xunlock(&modules_sx)
#define MOD_SUNLOCK sx_sunlock(&modules_sx)
#define MOD_LOCK_ASSERT sx_assert(&modules_sx, SX_LOCKED)
#define MOD_XLOCK_ASSERT sx_assert(&modules_sx, SX_XLOCKED)
struct linker_file;
void module_register_init(const void *);
int module_register(const struct moduledata *, struct linker_file *);
module_t module_lookupbyname(const char *);
module_t module_lookupbyid(int);
int module_quiesce(module_t);
void module_reference(module_t);
void module_release(module_t);
int module_unload(module_t);
int module_getid(module_t);
module_t module_getfnext(module_t);
const char * module_getname(module_t);
void module_setspecific(module_t, modspecific_t *);
struct linker_file *module_file(module_t);
#ifdef MOD_DEBUG
extern int mod_debug;
#define MOD_DEBUG_REFS 1
#define MOD_DPF(cat, args) do { \
if (mod_debug & MOD_DEBUG_##cat) \
printf(args); \
} while (0)
#else /* !MOD_DEBUG */
#define MOD_DPF(cat, args)
#endif
#endif /* _KERNEL */
#define MAXMODNAME 32
struct module_stat {
int version; /* set to sizeof(struct module_stat) */
char name[MAXMODNAME];
int refs;
int id;
modspecific_t data;
};
#ifndef _KERNEL
#include <sys/cdefs.h>
__BEGIN_DECLS
int modnext(int _modid);
int modfnext(int _modid);
int modstat(int _modid, struct module_stat *_stat);
int modfind(const char *_name);
__END_DECLS
#endif
#endif /* !_SYS_MODULE_H_ */