servers/pm/utility.c

   1 /* This file contains some utility routines for PM.
   2  *
   3  * The entry points are:
   4  *   get_free_pid:      get a free process or group id
   5  *   no_sys:            called for invalid system call numbers
   6  *   find_param:        look up a boot monitor parameter
   7  *   find_proc:         return process pointer from pid number
   8  *   pm_isokendpt:      check the validity of an endpoint
   9  *   tell_fs:           send a request to FS on behalf of a process
  10  */
  11
  12 #include "pm.h"
  13 #include <sys/stat.h>
  14 #include <minix/callnr.h>
  15 #include <minix/com.h>
  16 #include <minix/endpoint.h>
  17 #include <fcntl.h>
  18 #include <signal.h>             /* needed only because mproc.h needs it */
  19 #include "mproc.h"
  20 #include "param.h"
  21
  22 #include <minix/config.h>
  23 #include <timers.h>
  24 #include <string.h>
  25 #include <machine/archtypes.h>
  26 #include "kernel/const.h"
  27 #include "kernel/config.h"
  28 #include "kernel/type.h"
  29 #include "kernel/proc.h"
  30
  31 #define munmap _munmap
  32 #define munmap_text _munmap_text
  33 #include <sys/mman.h>
  34 #undef munmap
  35 #undef munmap_text
  36
  37 /*===========================================================================*
  38  *                              get_free_pid                                 *
  39  *===========================================================================*/
  40 PUBLIC pid_t get_free_pid()
  41 {
  42   static pid_t next_pid = INIT_PID + 1;         /* next pid to be assigned */
  43   register struct mproc *rmp;                   /* check process table */
  44   int t;                                        /* zero if pid still free */
  45
  46   /* Find a free pid for the child and put it in the table. */
  47   do {
  48         t = 0;
  49         next_pid = (next_pid < NR_PIDS ? next_pid + 1 : INIT_PID + 1);
  50         for (rmp = &mproc[0]; rmp < &mproc[NR_PROCS]; rmp++)
  51                 if (rmp->mp_pid == next_pid || rmp->mp_procgrp == next_pid) {
  52                         t = 1;
  53                         break;
  54                 }
  55   } while (t);                                  /* 't' = 0 means pid free */
  56   return(next_pid);
  57 }
  58
  59
  60 /*===========================================================================*
  61  *                              no_sys                                       *
  62  *===========================================================================*/
  63 PUBLIC int no_sys()
  64 {
  65 /* A system call number not implemented by PM has been requested. */
  66   printf("PM: in no_sys, call nr %d from %d\n", call_nr, who_e);
  67   return(ENOSYS);
  68 }
  69
  70 /*===========================================================================*
  71  *                              find_param                                   *
  72  *===========================================================================*/
  73 PUBLIC char *find_param(name)
  74 const char *name;
  75 {
  76   register const char *namep;
  77   register char *envp;
  78
  79   for (envp = (char *) monitor_params; *envp != 0;) {
  80         for (namep = name; *namep != 0 && *namep == *envp; namep++, envp++)
  81                 ;
  82         if (*namep == '\0' && *envp == '=')
  83                 return(envp + 1);
  84         while (*envp++ != 0)
  85                 ;
  86   }
  87   return(NULL);
  88 }
  89
  90 /*===========================================================================*
  91  *                              find_proc                                    *
  92  *===========================================================================*/
  93 PUBLIC struct mproc *find_proc(lpid)
  94 pid_t lpid;
  95 {
  96   register struct mproc *rmp;
  97
  98   for (rmp = &mproc[0]; rmp < &mproc[NR_PROCS]; rmp++)
  99         if ((rmp->mp_flags & IN_USE) && rmp->mp_pid == lpid)
 100                 return(rmp);
 101
 102   return(NIL_MPROC);
 103 }
 104
 105 /*===========================================================================*
 106  *                              pm_isokendpt                                 *
 107  *===========================================================================*/
 108 PUBLIC int pm_isokendpt(int endpoint, int *proc)
 109 {
 110         *proc = _ENDPOINT_P(endpoint);
 111         if(*proc < -NR_TASKS || *proc >= NR_PROCS)
 112                 return EINVAL;
 113         if(*proc >= 0 && endpoint != mproc[*proc].mp_endpoint)
 114                 return EDEADSRCDST;
 115         if(*proc >= 0 && !(mproc[*proc].mp_flags & IN_USE))
 116                 return EDEADSRCDST;
 117         return OK;
 118 }
 119
 120 /*===========================================================================*
 121  *                              tell_fs                                      *
 122  *===========================================================================*/
 123 PUBLIC void tell_fs(rmp, m_ptr)
 124 struct mproc *rmp;
 125 message *m_ptr;
 126 {
 127 /* Send a request to VFS, without blocking.
 128  */
 129   int r;
 130
 131   if (rmp->mp_flags & FS_CALL)
 132         panic("tell_fs: not idle: %d", m_ptr->m_type);
 133
 134   r = asynsend3(FS_PROC_NR, m_ptr, AMF_NOREPLY);
 135   if (r != OK)
 136         panic("unable to send to FS: %d", r);
 137
 138   rmp->mp_flags |= FS_CALL;
 139 }
 140
 141 int unmap_ok = 0;
 142
 143 PUBLIC int munmap(void *addrstart, vir_bytes len)
 144 {
 145         if(!unmap_ok)
 146                 return ENOSYS;
 147
 148         return _munmap(addrstart, len);
 149 }
 150
 151 PUBLIC int munmap_text(void *addrstart, vir_bytes len)
 152 {
 153         if(!unmap_ok)
 154                 return ENOSYS;
 155
 156         return _munmap_text(addrstart, len);
 157
 158 }