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 <archconst.h>
  26 #include <archtypes.h>
  27 #include "../../kernel/const.h"
  28 #include "../../kernel/config.h"
  29 #include "../../kernel/type.h"
  30 #include "../../kernel/proc.h"
  31
  32 #define munmap _munmap
  33 #define munmap_text _munmap_text
  34 #include <sys/mman.h>
  35 #undef munmap
  36 #undef munmap_text
  37
  38 /*===========================================================================*
  39  *                              get_free_pid                                 *
  40  *===========================================================================*/
  41 PUBLIC pid_t get_free_pid()
  42 {
  43   static pid_t next_pid = INIT_PID + 1;         /* next pid to be assigned */
  44   register struct mproc *rmp;                   /* check process table */
  45   int t;                                        /* zero if pid still free */
  46
  47   /* Find a free pid for the child and put it in the table. */
  48   do {
  49         t = 0;
  50         next_pid = (next_pid < NR_PIDS ? next_pid + 1 : INIT_PID + 1);
  51         for (rmp = &mproc[0]; rmp < &mproc[NR_PROCS]; rmp++)
  52                 if (rmp->mp_pid == next_pid || rmp->mp_procgrp == next_pid) {
  53                         t = 1;
  54                         break;
  55                 }
  56   } while (t);                                  /* 't' = 0 means pid free */
  57   return(next_pid);
  58 }
  59
  60
  61 /*===========================================================================*
  62  *                              no_sys                                       *
  63  *===========================================================================*/
  64 PUBLIC int no_sys()
  65 {
  66 /* A system call number not implemented by PM has been requested. */
  67   printf("PM: in no_sys, call nr %d from %d\n", call_nr, who_e);
  68   return(ENOSYS);
  69 }
  70
  71 /*===========================================================================*
  72  *                              find_param                                   *
  73  *===========================================================================*/
  74 PUBLIC char *find_param(name)
  75 const char *name;
  76 {
  77   register const char *namep;
  78   register char *envp;
  79
  80   for (envp = (char *) monitor_params; *envp != 0;) {
  81         for (namep = name; *namep != 0 && *namep == *envp; namep++, envp++)
  82                 ;
  83         if (*namep == '\0' && *envp == '=')
  84                 return(envp + 1);
  85         while (*envp++ != 0)
  86                 ;
  87   }
  88   return(NULL);
  89 }
  90
  91 /*===========================================================================*
  92  *                              find_proc                                    *
  93  *===========================================================================*/
  94 PUBLIC struct mproc *find_proc(lpid)
  95 pid_t lpid;
  96 {
  97   register struct mproc *rmp;
  98
  99   for (rmp = &mproc[0]; rmp < &mproc[NR_PROCS]; rmp++)
 100         if ((rmp->mp_flags & IN_USE) && rmp->mp_pid == lpid)
 101                 return(rmp);
 102
 103   return(NIL_MPROC);
 104 }
 105
 106 /*===========================================================================*
 107  *                              pm_isokendpt                                 *
 108  *===========================================================================*/
 109 PUBLIC int pm_isokendpt(int endpoint, int *proc)
 110 {
 111         *proc = _ENDPOINT_P(endpoint);
 112         if(*proc < -NR_TASKS || *proc >= NR_PROCS)
 113                 return EINVAL;
 114         if(*proc >= 0 && endpoint != mproc[*proc].mp_endpoint)
 115                 return EDEADSRCDST;
 116         if(*proc >= 0 && !(mproc[*proc].mp_flags & IN_USE))
 117                 return EDEADSRCDST;
 118         return OK;
 119 }
 120
 121 /*===========================================================================*
 122  *                              tell_fs                                      *
 123  *===========================================================================*/
 124 PUBLIC void tell_fs(rmp, m_ptr)
 125 struct mproc *rmp;
 126 message *m_ptr;
 127 {
 128 /* Send a request to VFS, without blocking.
 129  */
 130   int r;
 131
 132   if (rmp->mp_flags & FS_CALL)
 133         panic("tell_fs: not idle: %d", m_ptr->m_type);
 134
 135   r = asynsend3(FS_PROC_NR, m_ptr, AMF_NOREPLY);
 136   if (r != OK)
 137         panic("unable to send to FS: %d", r);
 138
 139   rmp->mp_flags |= FS_CALL;
 140 }
 141
 142 int unmap_ok = 0;
 143
 144 PUBLIC int munmap(void *addrstart, vir_bytes len)
 145 {
 146         if(!unmap_ok)
 147                 return ENOSYS;
 148
 149         return _munmap(addrstart, len);
 150 }
 151
 152 PUBLIC int munmap_text(void *addrstart, vir_bytes len)
 153 {
 154         if(!unmap_ok)
 155                 return ENOSYS;
 156
 157         return _munmap_text(addrstart, len);
 158
 159 }