minix/servers/pm/main.c

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/* This file contains the main program of the process manager and some related
* procedures. When MINIX starts up, the kernel runs for a little while,
* initializing itself and its tasks, and then it runs PM and FS. Both PM
* and FS initialize themselves as far as they can. FS then makes a call to
* PM, because PM has to wait for FS to acquire a RAM disk. PM asks the
* kernel for all free memory and starts serving requests.
*
* The entry points into this file are:
* main: starts PM running
* setreply: set the reply to be sent to process making an PM system call
*/
#include "pm.h"
#include <minix/utils.h>
#include <minix/keymap.h>
#include <minix/callnr.h>
#include <minix/com.h>
#include <signal.h>
#include <fcntl.h>
#include <sys/ioc_memory.h>
#include <string.h>
#include "mproc.h"
#include "param.h"
#include "../../kernel/const.h"
#include "../../kernel/type.h"
FORWARD _PROTOTYPE( void get_work, (void) );
FORWARD _PROTOTYPE( void pm_init, (void) );
#define click_to_round_k(n) \
((unsigned) ((((unsigned long) (n) << CLICK_SHIFT) + 512) / 1024))
/*===========================================================================*
* main *
*===========================================================================*/
PUBLIC void main()
{
/* Main routine of the process manager. */
int result, s, proc_nr;
struct mproc *rmp;
pm_init(); /* initialize process manager tables */
/* This is PM's main loop- get work and do it, forever and forever. */
while (TRUE) {
get_work(); /* wait for an PM system call */
/* Check for system notifications first. Special cases. */
if (call_nr == HARD_STOP) { /* MINIX is shutting down */
check_sig(-1, SIGKILL); /* kill all processes */
sys_exit(0);
/* never reached */
} else if (call_nr == KSIG_PENDING) { /* signals pending */
(void) ksig_pending();
result = SUSPEND; /* don't reply */
}
/* Else, if the system call number is valid, perform the call. */
else if ((unsigned) call_nr >= NCALLS) {
result = ENOSYS;
} else {
result = (*call_vec[call_nr])();
}
/* Send the results back to the user to indicate completion. */
if (result != SUSPEND) setreply(who, result);
swap_in(); /* maybe a process can be swapped in? */
/* Send out all pending reply messages, including the answer to
* the call just made above. The processes must not be swapped out.
*/
for (proc_nr=0, rmp=mproc; proc_nr < NR_PROCS; proc_nr++, rmp++) {
if ((rmp->mp_flags & (REPLY | ONSWAP)) == REPLY) {
if ((s=send(proc_nr, &rmp->mp_reply)) != OK) {
panic(__FILE__,"PM can't reply to", proc_nr);
}
rmp->mp_flags &= ~REPLY;
}
}
}
}
/*===========================================================================*
* get_work *
*===========================================================================*/
PRIVATE void get_work()
{
/* Wait for the next message and extract useful information from it. */
if (receive(ANY, &m_in) != OK) panic(__FILE__,"PM receive error", NO_NUM);
who = m_in.m_source; /* who sent the message */
call_nr = m_in.m_type; /* system call number */
/* Process slot of caller. Misuse PM's own process slot if the kernel is
* calling. The can happen in case of pending kernel signals.
*/
mp = &mproc[who < 0 ? PM_PROC_NR : who];
}
/*===========================================================================*
* setreply *
*===========================================================================*/
PUBLIC void setreply(proc_nr, result)
int proc_nr; /* process to reply to */
int result; /* result of call (usually OK or error #) */
{
/* Fill in a reply message to be sent later to a user process. System calls
* may occasionally fill in other fields, this is only for the main return
* value, and for setting the "must send reply" flag.
*/
register struct mproc *rmp = &mproc[proc_nr];
rmp->mp_reply.reply_res = result;
rmp->mp_flags |= REPLY; /* reply pending */
if (rmp->mp_flags & ONSWAP)
swap_inqueue(rmp); /* must swap this process back in */
}
/*===========================================================================*
* pm_init *
*===========================================================================*/
PRIVATE void pm_init()
{
/* Initialize the process manager. */
int key, i, s;
static struct system_image image[IMAGE_SIZE];
register struct system_image *ip;
static char core_sigs[] = { SIGQUIT, SIGILL, SIGTRAP, SIGABRT,
SIGEMT, SIGFPE, SIGUSR1, SIGSEGV, SIGUSR2 };
static char ign_sigs[] = { SIGCHLD };
register int proc_nr;
register struct mproc *rmp;
register char *sig_ptr;
phys_clicks ram_clicks, total_clicks, minix_clicks, free_clicks;
message mess;
struct mem_map kernel_map[NR_LOCAL_SEGS];
int mem;
/* Build the set of signals which cause core dumps, and the set of signals
* that are by default ignored.
*/
sigemptyset(&core_sset);
for (sig_ptr = core_sigs; sig_ptr < core_sigs+sizeof(core_sigs); sig_ptr++)
sigaddset(&core_sset, *sig_ptr);
sigemptyset(&ign_sset);
for (sig_ptr = ign_sigs; sig_ptr < ign_sigs+sizeof(ign_sigs); sig_ptr++)
sigaddset(&ign_sset, *sig_ptr);
/* Get the memory map of the kernel to see how much memory it uses. */
if ((s=get_mem_map(SYSTASK, kernel_map)) != OK)
panic(__FILE__,"PM couldn't get proc entry of SYSTASK",s);
minix_clicks = (kernel_map[S].mem_phys + kernel_map[S].mem_len)
- kernel_map[T].mem_phys;
/* Initialize PM's tables. Request a copy of the system image table that
* is defined at the kernel level to see which slots to fill in.
*/
if (OK != (s=sys_getimage(&image))) {
printf("PM: warning, couldn't get system image table: %d\n", s);
}
procs_in_use = 0; /* start populating table */
for (ip = &image[0]; ip < &image[IMAGE_SIZE]; ip++) {
if (ip->proc_nr >= 0) { /* task have negative nrs */
procs_in_use += 1; /* found user process */
/* Set process details. */
rmp = &mproc[ip->proc_nr];
rmp->mp_flags |= IN_USE | DONT_SWAP;
rmp->mp_pid = (ip->proc_nr == INIT_PROC_NR) ?
INIT_PID : get_free_pid();
strncpy(rmp->mp_name, ip->proc_name, PROC_NAME_LEN);
/* Change signal handling behaviour. */
sigfillset(&rmp->mp_ignore);
sigfillset(&rmp->mp_sigmask);
sigemptyset(&rmp->mp_catch);
/* Get memory map for this process from the kernel. */
if ((s=get_mem_map(ip->proc_nr, rmp->mp_seg)) != OK)
panic(__FILE__,"couldn't get process entry",s);
if (rmp->mp_seg[T].mem_len != 0) rmp->mp_flags |= SEPARATE;
minix_clicks += rmp->mp_seg[S].mem_phys +
rmp->mp_seg[S].mem_len - rmp->mp_seg[T].mem_phys;
/* Tell FS about this system process. */
mess.PR_PROC_NR = ip->proc_nr;
mess.PR_PID = rmp->mp_pid;
if (OK != (s=send(FS_PROC_NR, &mess)))
panic(__FILE__,"PM can't sync up with FS", s);
}
}
/* Tell FS no more SYSTEM processes follow and synchronize. */
mess.PR_PROC_NR = NONE;
if (sendrec(FS_PROC_NR, &mess) != OK || mess.m_type != OK)
panic(__FILE__,"PM can't sync up with FS", NO_NUM);
/* INIT process is somewhat special. */
sigemptyset(&mproc[INIT_PROC_NR].mp_ignore);
sigemptyset(&mproc[INIT_PROC_NR].mp_sigmask);
sigemptyset(&mproc[INIT_PROC_NR].mp_catch);
/* Initialize tables to all physical memory. */
mem_init(&free_clicks);
total_clicks = minix_clicks + free_clicks;
/* Print memory information. */
printf("Memory size=%uK ", click_to_round_k(total_clicks));
printf("System services=%uK ", click_to_round_k(minix_clicks));
printf("Available=%uK\n\n", click_to_round_k(free_clicks));
}