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 * find_param: look up a boot monitor parameter 6 * find_proc: return process pointer from pid number 7 * nice_to_priority convert nice level to priority queue 8 * pm_isokendpt: check the validity of an endpoint 9 * tell_vfs: send a request to VFS on behalf of a process 10 */ 11 12 #include "pm.h" 13 #include <sys/resource.h> 14 #include <sys/stat.h> 15 #include <minix/callnr.h> 16 #include <minix/com.h> 17 #include <minix/endpoint.h> 18 #include <fcntl.h> 19 #include <signal.h> /* needed only because mproc.h needs it */ 20 #include "mproc.h" 21 22 #include <minix/config.h> 23 #include <minix/timers.h> 24 #include <machine/archtypes.h> 25 #include "kernel/const.h" 26 #include "kernel/config.h" 27 #include "kernel/type.h" 28 #include "kernel/proc.h" 29 30 /*===========================================================================* 31 * get_free_pid * 32 *===========================================================================*/ 33 pid_t get_free_pid() 34 { 35 static pid_t next_pid = INIT_PID + 1; /* next pid to be assigned */ 36 register struct mproc *rmp; /* check process table */ 37 int t; /* zero if pid still free */ 38 39 /* Find a free pid for the child and put it in the table. */ 40 do { 41 t = 0; 42 next_pid = (next_pid < NR_PIDS ? next_pid + 1 : INIT_PID + 1); 43 for (rmp = &mproc[0]; rmp < &mproc[NR_PROCS]; rmp++) 44 if (rmp->mp_pid == next_pid || rmp->mp_procgrp == next_pid) { 45 t = 1; 46 break; 47 } 48 } while (t); /* 't' = 0 means pid free */ 49 return(next_pid); 50 } 51 52 /*===========================================================================* 53 * find_param * 54 *===========================================================================*/ 55 char *find_param(name) 56 const char *name; 57 { 58 register const char *namep; 59 register char *envp; 60 61 for (envp = (char *) monitor_params; *envp != 0;) { 62 for (namep = name; *namep != 0 && *namep == *envp; namep++, envp++) 63 ; 64 if (*namep == '\0' && *envp == '=') 65 return(envp + 1); 66 while (*envp++ != 0) 67 ; 68 } 69 return(NULL); 70 } 71 72 /*===========================================================================* 73 * find_proc * 74 *===========================================================================*/ 75 struct mproc *find_proc(lpid) 76 pid_t lpid; 77 { 78 register struct mproc *rmp; 79 80 for (rmp = &mproc[0]; rmp < &mproc[NR_PROCS]; rmp++) 81 if ((rmp->mp_flags & IN_USE) && rmp->mp_pid == lpid) 82 return(rmp); 83 84 return(NULL); 85 } 86 87 /*===========================================================================* 88 * nice_to_priority * 89 *===========================================================================*/ 90 int nice_to_priority(int nice, unsigned* new_q) 91 { 92 if (nice < PRIO_MIN || nice > PRIO_MAX) return(EINVAL); 93 94 *new_q = MAX_USER_Q + (nice-PRIO_MIN) * (MIN_USER_Q-MAX_USER_Q+1) / 95 (PRIO_MAX-PRIO_MIN+1); 96 97 /* Neither of these should ever happen. */ 98 if ((signed) *new_q < MAX_USER_Q) *new_q = MAX_USER_Q; 99 if (*new_q > MIN_USER_Q) *new_q = MIN_USER_Q; 100 101 return (OK); 102 } 103 104 /*===========================================================================* 105 * pm_isokendpt * 106 *===========================================================================*/ 107 int pm_isokendpt(int endpoint, int *proc) 108 { 109 *proc = _ENDPOINT_P(endpoint); 110 if (*proc < 0 || *proc >= NR_PROCS) 111 return EINVAL; 112 if (endpoint != mproc[*proc].mp_endpoint) 113 return EDEADEPT; 114 if (!(mproc[*proc].mp_flags & IN_USE)) 115 return EDEADEPT; 116 return OK; 117 } 118 119 /*===========================================================================* 120 * tell_vfs * 121 *===========================================================================*/ 122 void tell_vfs(rmp, m_ptr) 123 struct mproc *rmp; 124 message *m_ptr; 125 { 126 /* Send a request to VFS, without blocking. 127 */ 128 int r; 129 130 if (rmp->mp_flags & VFS_CALL) 131 panic("tell_vfs: not idle: %d", m_ptr->m_type); 132 133 r = asynsend3(VFS_PROC_NR, m_ptr, AMF_NOREPLY); 134 if (r != OK) 135 panic("unable to send to VFS: %d", r); 136 137 rmp->mp_flags |= VFS_CALL; 138 } 139