kern_ntptime.c revision 1.19
1 /* $NetBSD: kern_ntptime.c,v 1.19 2002/03/17 11:15:49 simonb 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 52 #include <sys/cdefs.h> 53 __KERNEL_RCSID(0, "$NetBSD: kern_ntptime.c,v 1.19 2002/03/17 11:15:49 simonb Exp $"); 54 55 #include "opt_ntp.h" 56 57 #include <sys/param.h> 58 #include <sys/resourcevar.h> 59 #include <sys/systm.h> 60 #include <sys/kernel.h> 61 #include <sys/proc.h> 62 #include <sys/sysctl.h> 63 #include <sys/timex.h> 64 #include <sys/vnode.h> 65 66 #include <sys/mount.h> 67 #include <sys/syscallargs.h> 68 69 #include <machine/cpu.h> 70 71 #ifdef NTP 72 /* 73 * The following variables are used by the hardclock() routine in the 74 * kern_clock.c module and are described in that module. 75 */ 76 extern int time_state; /* clock state */ 77 extern int time_status; /* clock status bits */ 78 extern long time_offset; /* time adjustment (us) */ 79 extern long time_freq; /* frequency offset (scaled ppm) */ 80 extern long time_maxerror; /* maximum error (us) */ 81 extern long time_esterror; /* estimated error (us) */ 82 extern long time_constant; /* pll time constant */ 83 extern long time_precision; /* clock precision (us) */ 84 extern long time_tolerance; /* frequency tolerance (scaled ppm) */ 85 86 #ifdef PPS_SYNC 87 /* 88 * The following variables are used only if the PPS signal discipline 89 * is configured in the kernel. 90 */ 91 extern int pps_shift; /* interval duration (s) (shift) */ 92 extern long pps_freq; /* pps frequency offset (scaled ppm) */ 93 extern long pps_jitter; /* pps jitter (us) */ 94 extern long pps_stabil; /* pps stability (scaled ppm) */ 95 extern long pps_jitcnt; /* jitter limit exceeded */ 96 extern long pps_calcnt; /* calibration intervals */ 97 extern long pps_errcnt; /* calibration errors */ 98 extern long pps_stbcnt; /* stability limit exceeded */ 99 #endif /* PPS_SYNC */ 100 101 /*ARGSUSED*/ 102 /* 103 * ntp_gettime() - NTP user application interface 104 */ 105 int 106 sys_ntp_gettime(p, v, retval) 107 struct proc *p; 108 void *v; 109 register_t *retval; 110 111 { 112 struct sys_ntp_gettime_args /* { 113 syscallarg(struct ntptimeval *) ntvp; 114 } */ *uap = v; 115 struct timeval atv; 116 struct ntptimeval ntv; 117 int error = 0; 118 int s; 119 120 if (SCARG(uap, ntvp)) { 121 s = splclock(); 122 #ifdef EXT_CLOCK 123 /* 124 * The microtime() external clock routine returns a 125 * status code. If less than zero, we declare an error 126 * in the clock status word and return the kernel 127 * (software) time variable. While there are other 128 * places that call microtime(), this is the only place 129 * that matters from an application point of view. 130 */ 131 if (microtime(&atv) < 0) { 132 time_status |= STA_CLOCKERR; 133 ntv.time = time; 134 } else 135 time_status &= ~STA_CLOCKERR; 136 #else /* EXT_CLOCK */ 137 microtime(&atv); 138 #endif /* EXT_CLOCK */ 139 ntv.time = atv; 140 ntv.maxerror = time_maxerror; 141 ntv.esterror = time_esterror; 142 (void) splx(s); 143 144 error = copyout((caddr_t)&ntv, (caddr_t)SCARG(uap, ntvp), 145 sizeof(ntv)); 146 } 147 if (!error) { 148 149 /* 150 * Status word error decode. If any of these conditions 151 * occur, an error is returned, instead of the status 152 * word. Most applications will care only about the fact 153 * the system clock may not be trusted, not about the 154 * details. 155 * 156 * Hardware or software error 157 */ 158 if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) || 159 160 /* 161 * PPS signal lost when either time or frequency 162 * synchronization requested 163 */ 164 (time_status & (STA_PPSFREQ | STA_PPSTIME) && 165 !(time_status & STA_PPSSIGNAL)) || 166 167 /* 168 * PPS jitter exceeded when time synchronization 169 * requested 170 */ 171 (time_status & STA_PPSTIME && 172 time_status & STA_PPSJITTER) || 173 174 /* 175 * PPS wander exceeded or calibration error when 176 * frequency synchronization requested 177 */ 178 (time_status & STA_PPSFREQ && 179 time_status & (STA_PPSWANDER | STA_PPSERROR))) 180 *retval = TIME_ERROR; 181 else 182 *retval = (register_t)time_state; 183 } 184 return(error); 185 } 186 187 /* ARGSUSED */ 188 /* 189 * ntp_adjtime() - NTP daemon application interface 190 */ 191 int 192 sys_ntp_adjtime(p, v, retval) 193 struct proc *p; 194 void *v; 195 register_t *retval; 196 { 197 struct sys_ntp_adjtime_args /* { 198 syscallarg(struct timex *) tp; 199 } */ *uap = v; 200 struct timex ntv; 201 int error = 0; 202 203 if ((error = copyin((caddr_t)SCARG(uap, tp), (caddr_t)&ntv, 204 sizeof(ntv))) != 0) 205 return (error); 206 207 if (ntv.modes != 0 && (error = suser(p->p_ucred, &p->p_acflag)) != 0) 208 return (error); 209 210 return (ntp_adjtime1(&ntv, v, retval)); 211 } 212 213 int 214 ntp_adjtime1(ntv, v, retval) 215 struct timex *ntv; 216 void *v; 217 register_t *retval; 218 { 219 struct sys_ntp_adjtime_args /* { 220 syscallarg(struct timex *) tp; 221 } */ *uap = v; 222 int error = 0; 223 int modes; 224 int s; 225 226 /* 227 * Update selected clock variables. Note that there is no error 228 * checking here on the assumption the superuser should know 229 * what it is doing. 230 */ 231 modes = ntv->modes; 232 s = splclock(); 233 if (modes & MOD_FREQUENCY) 234 #ifdef PPS_SYNC 235 time_freq = ntv->freq - pps_freq; 236 #else /* PPS_SYNC */ 237 time_freq = ntv->freq; 238 #endif /* PPS_SYNC */ 239 if (modes & MOD_MAXERROR) 240 time_maxerror = ntv->maxerror; 241 if (modes & MOD_ESTERROR) 242 time_esterror = ntv->esterror; 243 if (modes & MOD_STATUS) { 244 time_status &= STA_RONLY; 245 time_status |= ntv->status & ~STA_RONLY; 246 } 247 if (modes & MOD_TIMECONST) 248 time_constant = ntv->constant; 249 if (modes & MOD_OFFSET) 250 hardupdate(ntv->offset); 251 252 /* 253 * Retrieve all clock variables 254 */ 255 if (time_offset < 0) 256 ntv->offset = -(-time_offset >> SHIFT_UPDATE); 257 else 258 ntv->offset = time_offset >> SHIFT_UPDATE; 259 #ifdef PPS_SYNC 260 ntv->freq = time_freq + pps_freq; 261 #else /* PPS_SYNC */ 262 ntv->freq = time_freq; 263 #endif /* PPS_SYNC */ 264 ntv->maxerror = time_maxerror; 265 ntv->esterror = time_esterror; 266 ntv->status = time_status; 267 ntv->constant = time_constant; 268 ntv->precision = time_precision; 269 ntv->tolerance = time_tolerance; 270 #ifdef PPS_SYNC 271 ntv->shift = pps_shift; 272 ntv->ppsfreq = pps_freq; 273 ntv->jitter = pps_jitter >> PPS_AVG; 274 ntv->stabil = pps_stabil; 275 ntv->calcnt = pps_calcnt; 276 ntv->errcnt = pps_errcnt; 277 ntv->jitcnt = pps_jitcnt; 278 ntv->stbcnt = pps_stbcnt; 279 #endif /* PPS_SYNC */ 280 (void)splx(s); 281 282 error = copyout((caddr_t)ntv, (caddr_t)SCARG(uap, tp), sizeof(*ntv)); 283 if (!error) { 284 285 /* 286 * Status word error decode. See comments in 287 * ntp_gettime() routine. 288 */ 289 if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) || 290 (time_status & (STA_PPSFREQ | STA_PPSTIME) && 291 !(time_status & STA_PPSSIGNAL)) || 292 (time_status & STA_PPSTIME && 293 time_status & STA_PPSJITTER) || 294 (time_status & STA_PPSFREQ && 295 time_status & (STA_PPSWANDER | STA_PPSERROR))) 296 *retval = TIME_ERROR; 297 else 298 *retval = (register_t)time_state; 299 } 300 return error; 301 } 302 303 /* 304 * return information about kernel precision timekeeping 305 */ 306 int 307 sysctl_ntptime(where, sizep) 308 void *where; 309 size_t *sizep; 310 { 311 struct timeval atv; 312 struct ntptimeval ntv; 313 int s; 314 315 /* 316 * Construct ntp_timeval. 317 */ 318 319 s = splclock(); 320 #ifdef EXT_CLOCK 321 /* 322 * The microtime() external clock routine returns a 323 * status code. If less than zero, we declare an error 324 * in the clock status word and return the kernel 325 * (software) time variable. While there are other 326 * places that call microtime(), this is the only place 327 * that matters from an application point of view. 328 */ 329 if (microtime(&atv) < 0) { 330 time_status |= STA_CLOCKERR; 331 ntv.time = time; 332 } else { 333 time_status &= ~STA_CLOCKERR; 334 } 335 #else /* EXT_CLOCK */ 336 microtime(&atv); 337 #endif /* EXT_CLOCK */ 338 ntv.time = atv; 339 ntv.maxerror = time_maxerror; 340 ntv.esterror = time_esterror; 341 splx(s); 342 343 #ifdef notyet 344 /* 345 * Status word error decode. If any of these conditions 346 * occur, an error is returned, instead of the status 347 * word. Most applications will care only about the fact 348 * the system clock may not be trusted, not about the 349 * details. 350 * 351 * Hardware or software error 352 */ 353 if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) || 354 ntv.time_state = TIME_ERROR; 355 356 /* 357 * PPS signal lost when either time or frequency 358 * synchronization requested 359 */ 360 (time_status & (STA_PPSFREQ | STA_PPSTIME) && 361 !(time_status & STA_PPSSIGNAL)) || 362 363 /* 364 * PPS jitter exceeded when time synchronization 365 * requested 366 */ 367 (time_status & STA_PPSTIME && 368 time_status & STA_PPSJITTER) || 369 370 /* 371 * PPS wander exceeded or calibration error when 372 * frequency synchronization requested 373 */ 374 (time_status & STA_PPSFREQ && 375 time_status & (STA_PPSWANDER | STA_PPSERROR))) 376 ntv.time_state = TIME_ERROR; 377 else 378 ntv.time_state = time_state; 379 #endif /* notyet */ 380 return (sysctl_rdstruct(where, sizep, NULL, &ntv, sizeof(ntv))); 381 } 382 #else /* !NTP */ 383 /* For some reason, raising SIGSYS (as sys_nosys would) is problematic. */ 384 385 int 386 sys_ntp_gettime(p, v, retval) 387 struct proc *p; 388 void *v; 389 register_t *retval; 390 { 391 392 return(ENOSYS); 393 } 394 #endif /* !NTP */ 395
Indexes created Tue Sep 23 07:09:52 GMT 2025