minix/lib/syslib/sef_init.c
Cristiano Giuffrida d1fd04e72a Initialization protocol for system services.
SYSLIB CHANGES:
- SEF framework now supports a new SEF Init request type from RS. 3 different
callbacks are available (init_fresh, init_lu, init_restart) to specify
initialization code when a service starts fresh, starts after a live update,
or restarts.

SYSTEM SERVICE CHANGES:
- Initialization code for system services is now enclosed in a callback SEF will
automatically call at init time. The return code of the callback will
tell RS whether the initialization completed successfully.
- Each init callback can access information passed by RS to initialize. As of
now, each system service has access to the public entries of RS's system process
table to gather all the information required to initialize. This design
eliminates many existing or potential races at boot time and provides a uniform
initialization interface to system services. The same interface will be reused
for the upcoming publish/subscribe model to handle dynamic 
registration / deregistration of system services.

VM CHANGES:
- Uniform privilege management for all system services. Every service uses the
same call mask format. For boot services, VM copies the call mask from init
data. For dynamic services, VM still receives the call mask via rs_set_priv
call that will be soon replaced by the upcoming publish/subscribe model.

RS CHANGES:
- The system process table has been reorganized and split into private entries
and public entries. Only the latter ones are exposed to system services.
- VM call masks are now entirely configured in rs/table.c
- RS has now its own slot in the system process table. Only kernel tasks and
user processes not included in the boot image are now left out from the system
process table.
- RS implements the initialization protocol for system services.
- For services in the boot image, RS blocks till initialization is complete and
panics when failure is reported back. Services are initialized in their order of
appearance in the boot image priv table and RS blocks to implements synchronous
initialization for every system service having the flag SF_SYNCH_BOOT set.
- For services started dynamically, the initialization protocol is implemented
as though it were the first ping for the service. In this case, if the
system service fails to report back (or reports failure), RS brings the service
down rather than trying to restart it.
2010-01-08 01:20:42 +00:00

137 lines
4.5 KiB
C

#include "syslib.h"
#include <assert.h>
#include <minix/sysutil.h>
/* SEF Init callbacks. */
PRIVATE struct sef_cbs {
sef_cb_init_fresh_t sef_cb_init_fresh;
sef_cb_init_lu_t sef_cb_init_lu;
sef_cb_init_restart_t sef_cb_init_restart;
} sef_cbs = {
SEF_CB_INIT_FRESH_DEFAULT,
SEF_CB_INIT_LU_DEFAULT,
SEF_CB_INIT_RESTART_DEFAULT
};
/* SEF Init prototypes for sef_startup(). */
PUBLIC _PROTOTYPE( int do_sef_rs_init, (void) );
PUBLIC _PROTOTYPE( int do_sef_init_request, (message *m_ptr) );
/* Debug. */
EXTERN _PROTOTYPE( char* sef_debug_header, (void) );
/*===========================================================================*
* do_sef_rs_init *
*===========================================================================*/
PUBLIC int do_sef_rs_init()
{
/* Special SEF Init for RS. */
return sef_cbs.sef_cb_init_fresh(SEF_INIT_FRESH, NULL);
}
/*===========================================================================*
* do_sef_init_request *
*===========================================================================*/
PUBLIC int do_sef_init_request(message *m_ptr)
{
/* Handle a SEF Init request. */
int r;
int type;
sef_init_info_t info;
/* Debug. */
#if SEF_INIT_DEBUG
sef_init_debug_begin();
sef_init_dprint("%s. Got a SEF Init request of type: %d. About to init.\n",
sef_debug_header(), m_ptr->RS_INIT_TYPE);
sef_init_debug_end();
#endif
/* Let the callback code handle the request. */
type = m_ptr->RS_INIT_TYPE;
info.rproctab_gid = m_ptr->RS_INIT_RPROCTAB_GID;
switch(type) {
case SEF_INIT_FRESH:
r = sef_cbs.sef_cb_init_fresh(type, &info);
break;
case SEF_INIT_LU:
r = sef_cbs.sef_cb_init_lu(type, &info);
break;
case SEF_INIT_RESTART:
r = sef_cbs.sef_cb_init_restart(type, &info);
break;
default:
/* Not a valid SEF init type. */
r = EINVAL;
break;
}
/* Report back to RS. XXX FIXME: we should use send, but this would cause
* a deadlock due to the current blocking nature of mapdriver().
*/
m_ptr->RS_INIT_RESULT = r;
r = asynsend(RS_PROC_NR, m_ptr);
return r;
}
/*===========================================================================*
* sef_setcb_init_fresh *
*===========================================================================*/
PUBLIC void sef_setcb_init_fresh(sef_cb_init_fresh_t cb)
{
assert(cb != NULL);
sef_cbs.sef_cb_init_fresh = cb;
}
/*===========================================================================*
* sef_setcb_init_lu *
*===========================================================================*/
PUBLIC void sef_setcb_init_lu(sef_cb_init_lu_t cb)
{
assert(cb != NULL);
sef_cbs.sef_cb_init_lu = cb;
}
/*===========================================================================*
* sef_setcb_init_restart *
*===========================================================================*/
PUBLIC void sef_setcb_init_restart(sef_cb_init_restart_t cb)
{
assert(cb != NULL);
sef_cbs.sef_cb_init_restart = cb;
}
/*===========================================================================*
* sef_cb_init_fresh_null *
*===========================================================================*/
PUBLIC int sef_cb_init_fresh_null(int type, sef_init_info_t *info)
{
return(OK);
}
/*===========================================================================*
* sef_cb_init_lu_null *
*===========================================================================*/
PUBLIC int sef_cb_init_lu_null(int type, sef_init_info_t *info)
{
return(OK);
}
/*===========================================================================*
* sef_cb_init_restart_null *
*===========================================================================*/
PUBLIC int sef_cb_init_restart_null(int type, sef_init_info_t *info)
{
return(OK);
}
/*===========================================================================*
* sef_cb_init_restart_fail *
*===========================================================================*/
PUBLIC int sef_cb_init_restart_fail(int type, sef_init_info_t *info)
{
return(ENOSYS);
}