_fini(9E) Driver Entry Points _fini(9E)
NAME
_fini, _info, _init - loadable module configuration entry points
SYNOPSIS
#include <sys/modctl.h>
int _fini(void);
int _info(struct modinfo *modinfop);
int _init(void);
INTERFACE LEVEL
Solaris DDI specific (Solaris DDI). These entry points are required. You must write them.
PARAMETERS
_info()
modinfop A pointer to an opaque modinfo structure.
DESCRIPTION
_init() initializes a loadable module. It is called before any other routine in a loadable module. _init() returns the value returned by
mod_install(9F). The module may optionally perform some other work before the mod_install(9F) call is performed. If the module has done
some setup before the mod_install(9F) function is called, then it should be prepared to undo that setup if mod_install(9F) returns an
error.
_info() returns information about a loadable module. _info() returns the value returned by mod_info(9F).
_fini() prepares a loadable module for unloading. It is called when the system wants to unload a module. If the module determines that it
can be unloaded, then _fini() returns the value returned by mod_remove(9F). Upon successful return from _fini() no other routine in the
module will be called before _init() is called.
RETURN VALUES
_init() should return the appropriate error number if there is an error, otherwise it should return the return value from mod_install(9F).
_info() should return the return value from mod_info(9F)
_fini() should return the return value from mod_remove(9F). _fini() is permitted to return EBUSY prior to calling mod_remove(9F) if the
driver should not be unloaded. Driver global resources, such as mutexes and calls to ddi_soft_state_fini(9F), should only be destroyed in
_fini() after mod_remove() returns successfully.
EXAMPLES
Example 1: Initializing and Freeing a Mutex
The following example demonstrates how to initialize and free a mutex(9F).
#include <sys/modctl.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
static struct dev_ops drv_ops;
/*
* Module linkage information for the kernel.
*/
static struct modldrv modldrv = {
&mod_driverops, /* Type of module. This one is a driver */
"Sample Driver",
&drv_ops /* driver ops */
};
static struct modlinkage modlinkage = {
MODREV_1,
&modldrv,
NULL
};
/*
* Global driver mutex
*/
static kmutex_t xx_global_mutex;
int
_init(void)
{
int i;
/*
* Initialize global mutex before mod_install'ing driver.
* If mod_install() fails, must clean up mutex initialization
*/
mutex_init(&xx_global_mutex, NULL,
MUTEX_DRIVER, (void *)NULL);
if ((i = mod_install(&modlinkage)) != 0) {
mutex_destroy(&xx_global_mutex);
}
return (i);
}
int
_info(struct modinfo *modinfop)
{
return (mod_info(&modlinkage, modinfop));
}
int
_fini(void)
{
int i;
/*
* If mod_remove() is successful, we destroy our global mutex
*/
if ((i = mod_remove(&modlinkage)) == 0) {
mutex_destroy(&xx_global_mutex);
}
return (i);
}
SEE ALSO
add_drv(1M), mod_info(9F), mod_install(9F), mod_remove(9F), mutex(9F), modldrv(9S), modlinkage(9S), modlstrmod(9S)
Writing Device Drivers
WARNINGS
Do not change the structures referred to by the modlinkage structure after the call to mod_install(), as the system may copy or change
them.
NOTES
Even though the identifiers _fini(), _info(), and _init() appear to be declared as globals, their scope is restricted by the kernel to the
module that they are defined in.
BUGS
On some implementations _info() may be called before _init().
SunOS 5.10 22 Jan 2002 _fini(9E)