kern_ntptime.c revision 1.15
1 /* $NetBSD: kern_ntptime.c,v 1.15 2001/09/16 09:55:26 jmc Exp $ */ 2 3 /****************************************************************************** 4 * * 5 * Copyright (c) David L. Mills 1993, 1994 * 6 * * 7 * Permission to use, copy, modify, and distribute this software and its * 8 * documentation for any purpose and without fee is hereby granted, provided * 9 * that the above copyright notice appears in all copies and that both the * 10 * copyright notice and this permission notice appear in supporting * 11 * documentation, and that the name University of Delaware not be used in * 12 * advertising or publicity pertaining to distribution of the software * 13 * without specific, written prior permission. The University of Delaware * 14 * makes no representations about the suitability this software for any * 15 * purpose. It is provided "as is" without express or implied warranty. * 16 * * 17 ******************************************************************************/ 18 19 /* 20 * Modification history kern_ntptime.c 21 * 22 * 24 Sep 94 David L. Mills 23 * Tightened code at exits. 24 * 25 * 24 Mar 94 David L. Mills 26 * Revised syscall interface to include new variables for PPS 27 * time discipline. 28 * 29 * 14 Feb 94 David L. Mills 30 * Added code for external clock 31 * 32 * 28 Nov 93 David L. Mills 33 * Revised frequency scaling to conform with adjusted parameters 34 * 35 * 17 Sep 93 David L. Mills 36 * Created file 37 */ 38 /* 39 * ntp_gettime(), ntp_adjtime() - precision time interface for SunOS 40 * V4.1.1 and V4.1.3 41 * 42 * These routines consitute the Network Time Protocol (NTP) interfaces 43 * for user and daemon application programs. The ntp_gettime() routine 44 * provides the time, maximum error (synch distance) and estimated error 45 * (dispersion) to client user application programs. The ntp_adjtime() 46 * routine is used by the NTP daemon to adjust the system clock to an 47 * externally derived time. The time offset and related variables set by 48 * this routine are used by hardclock() to adjust the phase and 49 * frequency of the phase-lock loop which controls the system clock. 50 */ 51 #include "opt_ntp.h" 52 53 #include <sys/param.h> 54 #include <sys/resourcevar.h> 55 #include <sys/systm.h> 56 #include <sys/kernel.h> 57 #include <sys/proc.h> 58 #include <sys/timex.h> 59 #include <sys/vnode.h> 60 61 #include <sys/mount.h> 62 #include <sys/syscallargs.h> 63 64 #include <machine/cpu.h> 65 66 #include <uvm/uvm_extern.h> 67 #include <sys/sysctl.h> 68 69 #ifdef NTP 70 71 /* 72 * The following variables are used by the hardclock() routine in the 73 * kern_clock.c module and are described in that module. 74 */ 75 extern int time_state; /* clock state */ 76 extern int time_status; /* clock status bits */ 77 extern long time_offset; /* time adjustment (us) */ 78 extern long time_freq; /* frequency offset (scaled ppm) */ 79 extern long time_maxerror; /* maximum error (us) */ 80 extern long time_esterror; /* estimated error (us) */ 81 extern long time_constant; /* pll time constant */ 82 extern long time_precision; /* clock precision (us) */ 83 extern long time_tolerance; /* frequency tolerance (scaled ppm) */ 84 85 #ifdef PPS_SYNC 86 /* 87 * The following variables are used only if the PPS signal discipline 88 * is configured in the kernel. 89 */ 90 extern int pps_shift; /* interval duration (s) (shift) */ 91 extern long pps_freq; /* pps frequency offset (scaled ppm) */ 92 extern long pps_jitter; /* pps jitter (us) */ 93 extern long pps_stabil; /* pps stability (scaled ppm) */ 94 extern long pps_jitcnt; /* jitter limit exceeded */ 95 extern long pps_calcnt; /* calibration intervals */ 96 extern long pps_errcnt; /* calibration errors */ 97 extern long pps_stbcnt; /* stability limit exceeded */ 98 #endif /* PPS_SYNC */ 99 100 101 102 /*ARGSUSED*/ 103 /* 104 * ntp_gettime() - NTP user application interface 105 */ 106 int 107 sys_ntp_gettime(p, v, retval) 108 struct proc *p; 109 void *v; 110 register_t *retval; 111 112 { 113 struct sys_ntp_gettime_args /* { 114 syscallarg(struct ntptimeval *) ntvp; 115 } */ *uap = v; 116 struct timeval atv; 117 struct ntptimeval ntv; 118 int error = 0; 119 int s; 120 121 if (SCARG(uap, ntvp)) { 122 s = splclock(); 123 #ifdef EXT_CLOCK 124 /* 125 * The microtime() external clock routine returns a 126 * status code. If less than zero, we declare an error 127 * in the clock status word and return the kernel 128 * (software) time variable. While there are other 129 * places that call microtime(), this is the only place 130 * that matters from an application point of view. 131 */ 132 if (microtime(&atv) < 0) { 133 time_status |= STA_CLOCKERR; 134 ntv.time = time; 135 } else 136 time_status &= ~STA_CLOCKERR; 137 #else /* EXT_CLOCK */ 138 microtime(&atv); 139 #endif /* EXT_CLOCK */ 140 ntv.time = atv; 141 ntv.maxerror = time_maxerror; 142 ntv.esterror = time_esterror; 143 (void) splx(s); 144 145 error = copyout((caddr_t)&ntv, (caddr_t)SCARG(uap, ntvp), 146 sizeof(ntv)); 147 } 148 if (!error) { 149 150 /* 151 * Status word error decode. If any of these conditions 152 * occur, an error is returned, instead of the status 153 * word. Most applications will care only about the fact 154 * the system clock may not be trusted, not about the 155 * details. 156 * 157 * Hardware or software error 158 */ 159 if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) || 160 161 /* 162 * PPS signal lost when either time or frequency 163 * synchronization requested 164 */ 165 (time_status & (STA_PPSFREQ | STA_PPSTIME) && 166 !(time_status & STA_PPSSIGNAL)) || 167 168 /* 169 * PPS jitter exceeded when time synchronization 170 * requested 171 */ 172 (time_status & STA_PPSTIME && 173 time_status & STA_PPSJITTER) || 174 175 /* 176 * PPS wander exceeded or calibration error when 177 * frequency synchronization requested 178 */ 179 (time_status & STA_PPSFREQ && 180 time_status & (STA_PPSWANDER | STA_PPSERROR))) 181 *retval = TIME_ERROR; 182 else 183 *retval = (register_t)time_state; 184 } 185 return(error); 186 } 187 188 189 /* ARGSUSED */ 190 /* 191 * ntp_adjtime() - NTP daemon application interface 192 */ 193 int 194 sys_ntp_adjtime(p, v, retval) 195 struct proc *p; 196 void *v; 197 register_t *retval; 198 { 199 struct sys_ntp_adjtime_args /* { 200 syscallarg(struct timex *) tp; 201 } */ *uap = v; 202 struct timex ntv; 203 int error = 0; 204 205 if ((error = copyin((caddr_t)SCARG(uap, tp), (caddr_t)&ntv, 206 sizeof(ntv))) != 0) 207 return (error); 208 209 210 if (ntv.modes != 0 && (error = suser(p->p_ucred, &p->p_acflag)) != 0) 211 return (error); 212 213 return (ntp_adjtime1(&ntv, v, retval)); 214 } 215 216 int 217 ntp_adjtime1(ntv, v, retval) 218 struct timex *ntv; 219 void *v; 220 register_t *retval; 221 { 222 struct sys_ntp_adjtime_args /* { 223 syscallarg(struct timex *) tp; 224 } */ *uap = v; 225 int error = 0; 226 int modes; 227 int s; 228 229 /* 230 * Update selected clock variables. Note that there is no error 231 * checking here on the assumption the superuser should know 232 * what it is doing. 233 */ 234 modes = ntv->modes; 235 s = splclock(); 236 if (modes & MOD_FREQUENCY) 237 #ifdef PPS_SYNC 238 time_freq = ntv->freq - pps_freq; 239 #else /* PPS_SYNC */ 240 time_freq = ntv->freq; 241 #endif /* PPS_SYNC */ 242 if (modes & MOD_MAXERROR) 243 time_maxerror = ntv->maxerror; 244 if (modes & MOD_ESTERROR) 245 time_esterror = ntv->esterror; 246 if (modes & MOD_STATUS) { 247 time_status &= STA_RONLY; 248 time_status |= ntv->status & ~STA_RONLY; 249 } 250 if (modes & MOD_TIMECONST) 251 time_constant = ntv->constant; 252 if (modes & MOD_OFFSET) 253 hardupdate(ntv->offset); 254 255 /* 256 * Retrieve all clock variables 257 */ 258 if (time_offset < 0) 259 ntv->offset = -(-time_offset >> SHIFT_UPDATE); 260 else 261 ntv->offset = time_offset >> SHIFT_UPDATE; 262 #ifdef PPS_SYNC 263 ntv->freq = time_freq + pps_freq; 264 #else /* PPS_SYNC */ 265 ntv->freq = time_freq; 266 #endif /* PPS_SYNC */ 267 ntv->maxerror = time_maxerror; 268 ntv->esterror = time_esterror; 269 ntv->status = time_status; 270 ntv->constant = time_constant; 271 ntv->precision = time_precision; 272 ntv->tolerance = time_tolerance; 273 #ifdef PPS_SYNC 274 ntv->shift = pps_shift; 275 ntv->ppsfreq = pps_freq; 276 ntv->jitter = pps_jitter >> PPS_AVG; 277 ntv->stabil = pps_stabil; 278 ntv->calcnt = pps_calcnt; 279 ntv->errcnt = pps_errcnt; 280 ntv->jitcnt = pps_jitcnt; 281 ntv->stbcnt = pps_stbcnt; 282 #endif /* PPS_SYNC */ 283 (void)splx(s); 284 285 error = copyout((caddr_t)ntv, (caddr_t)SCARG(uap, tp), sizeof(*ntv)); 286 if (!error) { 287 288 /* 289 * Status word error decode. See comments in 290 * ntp_gettime() routine. 291 */ 292 if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) || 293 (time_status & (STA_PPSFREQ | STA_PPSTIME) && 294 !(time_status & STA_PPSSIGNAL)) || 295 (time_status & STA_PPSTIME && 296 time_status & STA_PPSJITTER) || 297 (time_status & STA_PPSFREQ && 298 time_status & (STA_PPSWANDER | STA_PPSERROR))) 299 *retval = TIME_ERROR; 300 else 301 *retval = (register_t)time_state; 302 } 303 return error; 304 } 305 306 307 308 /* 309 * return information about kernel precision timekeeping 310 */ 311 int 312 sysctl_ntptime(where, sizep) 313 void *where; 314 size_t *sizep; 315 { 316 struct timeval atv; 317 struct ntptimeval ntv; 318 int s; 319 320 /* 321 * Construct ntp_timeval. 322 */ 323 324 s = splclock(); 325 #ifdef EXT_CLOCK 326 /* 327 * The microtime() external clock routine returns a 328 * status code. If less than zero, we declare an error 329 * in the clock status word and return the kernel 330 * (software) time variable. While there are other 331 * places that call microtime(), this is the only place 332 * that matters from an application point of view. 333 */ 334 if (microtime(&atv) < 0) { 335 time_status |= STA_CLOCKERR; 336 ntv.time = time; 337 } else { 338 time_status &= ~STA_CLOCKERR; 339 } 340 #else /* EXT_CLOCK */ 341 microtime(&atv); 342 #endif /* EXT_CLOCK */ 343 ntv.time = atv; 344 ntv.maxerror = time_maxerror; 345 ntv.esterror = time_esterror; 346 splx(s); 347 348 #ifdef notyet 349 /* 350 * Status word error decode. If any of these conditions 351 * occur, an error is returned, instead of the status 352 * word. Most applications will care only about the fact 353 * the system clock may not be trusted, not about the 354 * details. 355 * 356 * Hardware or software error 357 */ 358 if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) || 359 ntv.time_state = TIME_ERROR; 360 361 /* 362 * PPS signal lost when either time or frequency 363 * synchronization requested 364 */ 365 (time_status & (STA_PPSFREQ | STA_PPSTIME) && 366 !(time_status & STA_PPSSIGNAL)) || 367 368 /* 369 * PPS jitter exceeded when time synchronization 370 * requested 371 */ 372 (time_status & STA_PPSTIME && 373 time_status & STA_PPSJITTER) || 374 375 /* 376 * PPS wander exceeded or calibration error when 377 * frequency synchronization requested 378 */ 379 (time_status & STA_PPSFREQ && 380 time_status & (STA_PPSWANDER | STA_PPSERROR))) 381 ntv.time_state = TIME_ERROR; 382 else 383 ntv.time_state = time_state; 384 #endif /* notyet */ 385 return (sysctl_rdstruct(where, sizep, NULL, &ntv, sizeof(ntv))); 386 } 387 388 #else /* !NTP */ 389 390 /* For some reason, raising SIGSYS (as sys_nosys would) is problematic. */ 391 392 int 393 sys_ntp_gettime(p, v, retval) 394 struct proc *p; 395 void *v; 396 register_t *retval; 397 { 398 return(ENOSYS); 399 } 400 401 #endif /* !NTP */ 402
Indexes created Wed Sep 24 05:09:52 GMT 2025