Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/time.c |
| 3 | * |
| 4 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 5 | * |
| 6 | * This file contains the interface functions for the various |
| 7 | * time related system calls: time, stime, gettimeofday, settimeofday, |
| 8 | * adjtime |
| 9 | */ |
| 10 | /* |
| 11 | * Modification history kernel/time.c |
Daniel Walker | 6fa6c3b | 2007-10-18 03:06:03 -0700 | [diff] [blame] | 12 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | * 1993-09-02 Philip Gladstone |
Viresh Kumar | 0a0fca9 | 2013-06-04 13:10:24 +0530 | [diff] [blame] | 14 | * Created file with time related functions from sched/core.c and adjtimex() |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | * 1993-10-08 Torsten Duwe |
| 16 | * adjtime interface update and CMOS clock write code |
| 17 | * 1995-08-13 Torsten Duwe |
| 18 | * kernel PLL updated to 1994-12-13 specs (rfc-1589) |
| 19 | * 1999-01-16 Ulrich Windl |
| 20 | * Introduced error checking for many cases in adjtimex(). |
| 21 | * Updated NTP code according to technical memorandum Jan '96 |
| 22 | * "A Kernel Model for Precision Timekeeping" by Dave Mills |
| 23 | * Allow time_constant larger than MAXTC(6) for NTP v4 (MAXTC == 10) |
| 24 | * (Even though the technical memorandum forbids it) |
| 25 | * 2004-07-14 Christoph Lameter |
| 26 | * Added getnstimeofday to allow the posix timer functions to return |
| 27 | * with nanosecond accuracy |
| 28 | */ |
| 29 | |
Paul Gortmaker | 9984de1 | 2011-05-23 14:51:41 -0400 | [diff] [blame] | 30 | #include <linux/export.h> |
Geert Uytterhoeven | 8fd8658 | 2018-06-22 16:33:57 +0200 | [diff] [blame] | 31 | #include <linux/kernel.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | #include <linux/timex.h> |
Randy.Dunlap | c59ede7 | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 33 | #include <linux/capability.h> |
John Stultz | 189374a | 2012-09-04 15:27:48 -0400 | [diff] [blame] | 34 | #include <linux/timekeeper_internal.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | #include <linux/errno.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | #include <linux/syscalls.h> |
| 37 | #include <linux/security.h> |
| 38 | #include <linux/fs.h> |
Roman Zippel | 71abb3a | 2008-05-01 04:34:26 -0700 | [diff] [blame] | 39 | #include <linux/math64.h> |
Paul Mackerras | e3d5a27 | 2009-01-06 14:41:02 -0800 | [diff] [blame] | 40 | #include <linux/ptrace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | |
| 42 | #include <asm/uaccess.h> |
| 43 | #include <asm/unistd.h> |
| 44 | |
Nicholas Mc Guire | 0a22798 | 2015-05-18 14:19:12 +0200 | [diff] [blame] | 45 | #include <generated/timeconst.h> |
Thomas Gleixner | 8b094cd | 2014-07-16 21:04:02 +0000 | [diff] [blame] | 46 | #include "timekeeping.h" |
H. Peter Anvin | bdc8078 | 2008-02-08 04:21:26 -0800 | [diff] [blame] | 47 | |
Daniel Walker | 6fa6c3b | 2007-10-18 03:06:03 -0700 | [diff] [blame] | 48 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | * The timezone where the local system is located. Used as a default by some |
| 50 | * programs who obtain this value by using gettimeofday. |
| 51 | */ |
| 52 | struct timezone sys_tz; |
| 53 | |
| 54 | EXPORT_SYMBOL(sys_tz); |
| 55 | |
| 56 | #ifdef __ARCH_WANT_SYS_TIME |
| 57 | |
| 58 | /* |
| 59 | * sys_time() can be implemented in user-level using |
| 60 | * sys_gettimeofday(). Is this for backwards compatibility? If so, |
| 61 | * why not move it into the appropriate arch directory (for those |
| 62 | * architectures that need it). |
| 63 | */ |
Heiko Carstens | 58fd3aa | 2009-01-14 14:14:03 +0100 | [diff] [blame] | 64 | SYSCALL_DEFINE1(time, time_t __user *, tloc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | { |
Ingo Molnar | f20bf61 | 2007-10-16 16:09:20 +0200 | [diff] [blame] | 66 | time_t i = get_seconds(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | |
| 68 | if (tloc) { |
Linus Torvalds | 2008220 | 2007-07-20 13:28:54 -0700 | [diff] [blame] | 69 | if (put_user(i,tloc)) |
Paul Mackerras | e3d5a27 | 2009-01-06 14:41:02 -0800 | [diff] [blame] | 70 | return -EFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | } |
Paul Mackerras | e3d5a27 | 2009-01-06 14:41:02 -0800 | [diff] [blame] | 72 | force_successful_syscall_return(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | return i; |
| 74 | } |
| 75 | |
| 76 | /* |
| 77 | * sys_stime() can be implemented in user-level using |
| 78 | * sys_settimeofday(). Is this for backwards compatibility? If so, |
| 79 | * why not move it into the appropriate arch directory (for those |
| 80 | * architectures that need it). |
| 81 | */ |
Daniel Walker | 6fa6c3b | 2007-10-18 03:06:03 -0700 | [diff] [blame] | 82 | |
Heiko Carstens | 58fd3aa | 2009-01-14 14:14:03 +0100 | [diff] [blame] | 83 | SYSCALL_DEFINE1(stime, time_t __user *, tptr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | { |
| 85 | struct timespec tv; |
| 86 | int err; |
| 87 | |
| 88 | if (get_user(tv.tv_sec, tptr)) |
| 89 | return -EFAULT; |
| 90 | |
| 91 | tv.tv_nsec = 0; |
| 92 | |
| 93 | err = security_settime(&tv, NULL); |
| 94 | if (err) |
| 95 | return err; |
| 96 | |
| 97 | do_settimeofday(&tv); |
| 98 | return 0; |
| 99 | } |
| 100 | |
| 101 | #endif /* __ARCH_WANT_SYS_TIME */ |
| 102 | |
Heiko Carstens | 58fd3aa | 2009-01-14 14:14:03 +0100 | [diff] [blame] | 103 | SYSCALL_DEFINE2(gettimeofday, struct timeval __user *, tv, |
| 104 | struct timezone __user *, tz) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | { |
| 106 | if (likely(tv != NULL)) { |
| 107 | struct timeval ktv; |
| 108 | do_gettimeofday(&ktv); |
| 109 | if (copy_to_user(tv, &ktv, sizeof(ktv))) |
| 110 | return -EFAULT; |
| 111 | } |
| 112 | if (unlikely(tz != NULL)) { |
| 113 | if (copy_to_user(tz, &sys_tz, sizeof(sys_tz))) |
| 114 | return -EFAULT; |
| 115 | } |
| 116 | return 0; |
| 117 | } |
| 118 | |
| 119 | /* |
Prarit Bhargava | 84e345e | 2013-02-08 17:59:53 -0500 | [diff] [blame] | 120 | * Indicates if there is an offset between the system clock and the hardware |
| 121 | * clock/persistent clock/rtc. |
| 122 | */ |
| 123 | int persistent_clock_is_local; |
| 124 | |
| 125 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | * Adjust the time obtained from the CMOS to be UTC time instead of |
| 127 | * local time. |
Daniel Walker | 6fa6c3b | 2007-10-18 03:06:03 -0700 | [diff] [blame] | 128 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 129 | * This is ugly, but preferable to the alternatives. Otherwise we |
| 130 | * would either need to write a program to do it in /etc/rc (and risk |
Daniel Walker | 6fa6c3b | 2007-10-18 03:06:03 -0700 | [diff] [blame] | 131 | * confusion if the program gets run more than once; it would also be |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | * hard to make the program warp the clock precisely n hours) or |
| 133 | * compile in the timezone information into the kernel. Bad, bad.... |
| 134 | * |
H. Peter Anvin | bdc8078 | 2008-02-08 04:21:26 -0800 | [diff] [blame] | 135 | * - TYT, 1992-01-01 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | * |
| 137 | * The best thing to do is to keep the CMOS clock in universal time (UTC) |
| 138 | * as real UNIX machines always do it. This avoids all headaches about |
| 139 | * daylight saving times and warping kernel clocks. |
| 140 | */ |
Jesper Juhl | 77933d7 | 2005-07-27 11:46:09 -0700 | [diff] [blame] | 141 | static inline void warp_clock(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | { |
Dong Zhu | c30bd09 | 2012-12-06 22:03:34 +0800 | [diff] [blame] | 143 | if (sys_tz.tz_minuteswest != 0) { |
| 144 | struct timespec adjust; |
Thomas Gleixner | bd45b7a | 2010-05-23 08:14:45 +0200 | [diff] [blame] | 145 | |
Prarit Bhargava | 84e345e | 2013-02-08 17:59:53 -0500 | [diff] [blame] | 146 | persistent_clock_is_local = 1; |
John Stultz | 7859e40 | 2013-02-22 12:33:29 -0800 | [diff] [blame] | 147 | adjust.tv_sec = sys_tz.tz_minuteswest * 60; |
| 148 | adjust.tv_nsec = 0; |
| 149 | timekeeping_inject_offset(&adjust); |
Dong Zhu | c30bd09 | 2012-12-06 22:03:34 +0800 | [diff] [blame] | 150 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | } |
| 152 | |
| 153 | /* |
| 154 | * In case for some reason the CMOS clock has not already been running |
| 155 | * in UTC, but in some local time: The first time we set the timezone, |
| 156 | * we will warp the clock so that it is ticking UTC time instead of |
| 157 | * local time. Presumably, if someone is setting the timezone then we |
| 158 | * are running in an environment where the programs understand about |
| 159 | * timezones. This should be done at boot time in the /etc/rc script, |
| 160 | * as soon as possible, so that the clock can be set right. Otherwise, |
| 161 | * various programs will get confused when the clock gets warped. |
| 162 | */ |
| 163 | |
Baolin Wang | 86d3473 | 2016-04-08 14:02:12 +0800 | [diff] [blame] | 164 | int do_sys_settimeofday64(const struct timespec64 *tv, const struct timezone *tz) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | { |
| 166 | static int firsttime = 1; |
| 167 | int error = 0; |
| 168 | |
Baolin Wang | 86d3473 | 2016-04-08 14:02:12 +0800 | [diff] [blame] | 169 | if (tv && !timespec64_valid(tv)) |
Thomas Gleixner | 718bcce | 2006-01-09 20:52:29 -0800 | [diff] [blame] | 170 | return -EINVAL; |
| 171 | |
Baolin Wang | 86d3473 | 2016-04-08 14:02:12 +0800 | [diff] [blame] | 172 | error = security_settime64(tv, tz); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | if (error) |
| 174 | return error; |
| 175 | |
| 176 | if (tz) { |
Sasha Levin | 6f7d798 | 2014-12-01 23:04:06 -0500 | [diff] [blame] | 177 | /* Verify we're witin the +-15 hrs range */ |
| 178 | if (tz->tz_minuteswest > 15*60 || tz->tz_minuteswest < -15*60) |
| 179 | return -EINVAL; |
| 180 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | sys_tz = *tz; |
Tony Breeds | 2c62214 | 2007-10-18 03:04:57 -0700 | [diff] [blame] | 182 | update_vsyscall_tz(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | if (firsttime) { |
| 184 | firsttime = 0; |
| 185 | if (!tv) |
| 186 | warp_clock(); |
| 187 | } |
| 188 | } |
| 189 | if (tv) |
Baolin Wang | 86d3473 | 2016-04-08 14:02:12 +0800 | [diff] [blame] | 190 | return do_settimeofday64(tv); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | return 0; |
| 192 | } |
| 193 | |
Heiko Carstens | 58fd3aa | 2009-01-14 14:14:03 +0100 | [diff] [blame] | 194 | SYSCALL_DEFINE2(settimeofday, struct timeval __user *, tv, |
| 195 | struct timezone __user *, tz) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | { |
| 197 | struct timeval user_tv; |
Siddeswar Aluganti | c1c252d | 2017-12-04 18:21:37 -0800 | [diff] [blame] | 198 | struct timespec new_ts = {0}; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | struct timezone new_tz; |
| 200 | |
| 201 | if (tv) { |
| 202 | if (copy_from_user(&user_tv, tv, sizeof(*tv))) |
| 203 | return -EFAULT; |
Sasha Levin | 6ada1fc | 2014-12-03 19:22:48 -0500 | [diff] [blame] | 204 | |
| 205 | if (!timeval_valid(&user_tv)) |
| 206 | return -EINVAL; |
| 207 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | new_ts.tv_sec = user_tv.tv_sec; |
| 209 | new_ts.tv_nsec = user_tv.tv_usec * NSEC_PER_USEC; |
| 210 | } |
| 211 | if (tz) { |
| 212 | if (copy_from_user(&new_tz, tz, sizeof(*tz))) |
| 213 | return -EFAULT; |
| 214 | } |
| 215 | |
| 216 | return do_sys_settimeofday(tv ? &new_ts : NULL, tz ? &new_tz : NULL); |
| 217 | } |
| 218 | |
Heiko Carstens | 58fd3aa | 2009-01-14 14:14:03 +0100 | [diff] [blame] | 219 | SYSCALL_DEFINE1(adjtimex, struct timex __user *, txc_p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 220 | { |
| 221 | struct timex txc; /* Local copy of parameter */ |
| 222 | int ret; |
| 223 | |
| 224 | /* Copy the user data space into the kernel copy |
| 225 | * structure. But bear in mind that the structures |
| 226 | * may change |
| 227 | */ |
| 228 | if(copy_from_user(&txc, txc_p, sizeof(struct timex))) |
| 229 | return -EFAULT; |
| 230 | ret = do_adjtimex(&txc); |
| 231 | return copy_to_user(txc_p, &txc, sizeof(struct timex)) ? -EFAULT : ret; |
| 232 | } |
| 233 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | /** |
| 235 | * current_fs_time - Return FS time |
| 236 | * @sb: Superblock. |
| 237 | * |
Kalin KOZHUHAROV | 8ba8e95 | 2006-04-01 01:41:22 +0200 | [diff] [blame] | 238 | * Return the current time truncated to the time granularity supported by |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | * the fs. |
| 240 | */ |
| 241 | struct timespec current_fs_time(struct super_block *sb) |
| 242 | { |
| 243 | struct timespec now = current_kernel_time(); |
| 244 | return timespec_trunc(now, sb->s_time_gran); |
| 245 | } |
| 246 | EXPORT_SYMBOL(current_fs_time); |
| 247 | |
Eric Dumazet | 753e9c5 | 2007-05-08 00:25:32 -0700 | [diff] [blame] | 248 | /* |
| 249 | * Convert jiffies to milliseconds and back. |
| 250 | * |
| 251 | * Avoid unnecessary multiplications/divisions in the |
| 252 | * two most common HZ cases: |
| 253 | */ |
Greg Kroah-Hartman | af3b562 | 2013-02-21 16:42:40 -0800 | [diff] [blame] | 254 | unsigned int jiffies_to_msecs(const unsigned long j) |
Eric Dumazet | 753e9c5 | 2007-05-08 00:25:32 -0700 | [diff] [blame] | 255 | { |
| 256 | #if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ) |
| 257 | return (MSEC_PER_SEC / HZ) * j; |
| 258 | #elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC) |
| 259 | return (j + (HZ / MSEC_PER_SEC) - 1)/(HZ / MSEC_PER_SEC); |
| 260 | #else |
H. Peter Anvin | bdc8078 | 2008-02-08 04:21:26 -0800 | [diff] [blame] | 261 | # if BITS_PER_LONG == 32 |
Geert Uytterhoeven | 8fd8658 | 2018-06-22 16:33:57 +0200 | [diff] [blame] | 262 | return (HZ_TO_MSEC_MUL32 * j + (1ULL << HZ_TO_MSEC_SHR32) - 1) >> |
| 263 | HZ_TO_MSEC_SHR32; |
H. Peter Anvin | bdc8078 | 2008-02-08 04:21:26 -0800 | [diff] [blame] | 264 | # else |
Geert Uytterhoeven | 8fd8658 | 2018-06-22 16:33:57 +0200 | [diff] [blame] | 265 | return DIV_ROUND_UP(j * HZ_TO_MSEC_NUM, HZ_TO_MSEC_DEN); |
H. Peter Anvin | bdc8078 | 2008-02-08 04:21:26 -0800 | [diff] [blame] | 266 | # endif |
Eric Dumazet | 753e9c5 | 2007-05-08 00:25:32 -0700 | [diff] [blame] | 267 | #endif |
| 268 | } |
| 269 | EXPORT_SYMBOL(jiffies_to_msecs); |
| 270 | |
Greg Kroah-Hartman | af3b562 | 2013-02-21 16:42:40 -0800 | [diff] [blame] | 271 | unsigned int jiffies_to_usecs(const unsigned long j) |
Eric Dumazet | 753e9c5 | 2007-05-08 00:25:32 -0700 | [diff] [blame] | 272 | { |
Frederic Weisbecker | e075867 | 2014-10-10 02:44:01 +0200 | [diff] [blame] | 273 | /* |
| 274 | * Hz usually doesn't go much further MSEC_PER_SEC. |
| 275 | * jiffies_to_usecs() and usecs_to_jiffies() depend on that. |
| 276 | */ |
| 277 | BUILD_BUG_ON(HZ > USEC_PER_SEC); |
| 278 | |
| 279 | #if !(USEC_PER_SEC % HZ) |
Eric Dumazet | 753e9c5 | 2007-05-08 00:25:32 -0700 | [diff] [blame] | 280 | return (USEC_PER_SEC / HZ) * j; |
Eric Dumazet | 753e9c5 | 2007-05-08 00:25:32 -0700 | [diff] [blame] | 281 | #else |
H. Peter Anvin | bdc8078 | 2008-02-08 04:21:26 -0800 | [diff] [blame] | 282 | # if BITS_PER_LONG == 32 |
H. Peter Anvin | b9095fd | 2008-05-02 16:18:42 -0700 | [diff] [blame] | 283 | return (HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32; |
H. Peter Anvin | bdc8078 | 2008-02-08 04:21:26 -0800 | [diff] [blame] | 284 | # else |
| 285 | return (j * HZ_TO_USEC_NUM) / HZ_TO_USEC_DEN; |
| 286 | # endif |
Eric Dumazet | 753e9c5 | 2007-05-08 00:25:32 -0700 | [diff] [blame] | 287 | #endif |
| 288 | } |
| 289 | EXPORT_SYMBOL(jiffies_to_usecs); |
| 290 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | /** |
Kalin KOZHUHAROV | 8ba8e95 | 2006-04-01 01:41:22 +0200 | [diff] [blame] | 292 | * timespec_trunc - Truncate timespec to a granularity |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 293 | * @t: Timespec |
Kalin KOZHUHAROV | 8ba8e95 | 2006-04-01 01:41:22 +0200 | [diff] [blame] | 294 | * @gran: Granularity in ns. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 295 | * |
Karsten Blees | de4a95f | 2015-06-25 14:13:55 +0200 | [diff] [blame] | 296 | * Truncate a timespec to a granularity. Always rounds down. gran must |
| 297 | * not be 0 nor greater than a second (NSEC_PER_SEC, or 10^9 ns). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | */ |
| 299 | struct timespec timespec_trunc(struct timespec t, unsigned gran) |
| 300 | { |
Karsten Blees | de4a95f | 2015-06-25 14:13:55 +0200 | [diff] [blame] | 301 | /* Avoid division in the common cases 1 ns and 1 s. */ |
| 302 | if (gran == 1) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | /* nothing */ |
Karsten Blees | de4a95f | 2015-06-25 14:13:55 +0200 | [diff] [blame] | 304 | } else if (gran == NSEC_PER_SEC) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 305 | t.tv_nsec = 0; |
Karsten Blees | de4a95f | 2015-06-25 14:13:55 +0200 | [diff] [blame] | 306 | } else if (gran > 1 && gran < NSEC_PER_SEC) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | t.tv_nsec -= t.tv_nsec % gran; |
Karsten Blees | de4a95f | 2015-06-25 14:13:55 +0200 | [diff] [blame] | 308 | } else { |
| 309 | WARN(1, "illegal file time granularity: %u", gran); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | } |
| 311 | return t; |
| 312 | } |
| 313 | EXPORT_SYMBOL(timespec_trunc); |
| 314 | |
pang.xunlei | 90b6ce9 | 2014-11-18 19:15:18 +0800 | [diff] [blame] | 315 | /* |
| 316 | * mktime64 - Converts date to seconds. |
| 317 | * Converts Gregorian date to seconds since 1970-01-01 00:00:00. |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 318 | * Assumes input in normal date format, i.e. 1980-12-31 23:59:59 |
| 319 | * => year=1980, mon=12, day=31, hour=23, min=59, sec=59. |
| 320 | * |
| 321 | * [For the Julian calendar (which was used in Russia before 1917, |
| 322 | * Britain & colonies before 1752, anywhere else before 1582, |
| 323 | * and is still in use by some communities) leave out the |
| 324 | * -year/100+year/400 terms, and add 10.] |
| 325 | * |
| 326 | * This algorithm was first published by Gauss (I think). |
David Howells | ede5147 | 2016-02-24 14:37:53 +0000 | [diff] [blame] | 327 | * |
| 328 | * A leap second can be indicated by calling this function with sec as |
| 329 | * 60 (allowable under ISO 8601). The leap second is treated the same |
| 330 | * as the following second since they don't exist in UNIX time. |
| 331 | * |
| 332 | * An encoding of midnight at the end of the day as 24:00:00 - ie. midnight |
| 333 | * tomorrow - (allowable under ISO 8601) is supported. |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 334 | */ |
pang.xunlei | 90b6ce9 | 2014-11-18 19:15:18 +0800 | [diff] [blame] | 335 | time64_t mktime64(const unsigned int year0, const unsigned int mon0, |
| 336 | const unsigned int day, const unsigned int hour, |
| 337 | const unsigned int min, const unsigned int sec) |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 338 | { |
Ingo Molnar | f481890 | 2006-01-09 20:52:23 -0800 | [diff] [blame] | 339 | unsigned int mon = mon0, year = year0; |
| 340 | |
| 341 | /* 1..12 -> 11,12,1..10 */ |
| 342 | if (0 >= (int) (mon -= 2)) { |
| 343 | mon += 12; /* Puts Feb last since it has leap day */ |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 344 | year -= 1; |
| 345 | } |
| 346 | |
pang.xunlei | 90b6ce9 | 2014-11-18 19:15:18 +0800 | [diff] [blame] | 347 | return ((((time64_t) |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 348 | (year/4 - year/100 + year/400 + 367*mon/12 + day) + |
| 349 | year*365 - 719499 |
David Howells | ede5147 | 2016-02-24 14:37:53 +0000 | [diff] [blame] | 350 | )*24 + hour /* now have hours - midnight tomorrow handled here */ |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 351 | )*60 + min /* now have minutes */ |
| 352 | )*60 + sec; /* finally seconds */ |
| 353 | } |
pang.xunlei | 90b6ce9 | 2014-11-18 19:15:18 +0800 | [diff] [blame] | 354 | EXPORT_SYMBOL(mktime64); |
Andrew Morton | 199e705 | 2006-01-09 20:52:24 -0800 | [diff] [blame] | 355 | |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 356 | /** |
| 357 | * set_normalized_timespec - set timespec sec and nsec parts and normalize |
| 358 | * |
| 359 | * @ts: pointer to timespec variable to be set |
| 360 | * @sec: seconds to set |
| 361 | * @nsec: nanoseconds to set |
| 362 | * |
| 363 | * Set seconds and nanoseconds field of a timespec variable and |
| 364 | * normalize to the timespec storage format |
| 365 | * |
| 366 | * Note: The tv_nsec part is always in the range of |
H. Peter Anvin | bdc8078 | 2008-02-08 04:21:26 -0800 | [diff] [blame] | 367 | * 0 <= tv_nsec < NSEC_PER_SEC |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 368 | * For negative values only the tv_sec field is negative ! |
| 369 | */ |
Thomas Gleixner | 12e0933 | 2009-09-14 23:37:40 +0200 | [diff] [blame] | 370 | void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec) |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 371 | { |
| 372 | while (nsec >= NSEC_PER_SEC) { |
Thomas Gleixner | 12e0933 | 2009-09-14 23:37:40 +0200 | [diff] [blame] | 373 | /* |
| 374 | * The following asm() prevents the compiler from |
| 375 | * optimising this loop into a modulo operation. See |
| 376 | * also __iter_div_u64_rem() in include/linux/time.h |
| 377 | */ |
| 378 | asm("" : "+rm"(nsec)); |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 379 | nsec -= NSEC_PER_SEC; |
| 380 | ++sec; |
| 381 | } |
| 382 | while (nsec < 0) { |
Thomas Gleixner | 12e0933 | 2009-09-14 23:37:40 +0200 | [diff] [blame] | 383 | asm("" : "+rm"(nsec)); |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 384 | nsec += NSEC_PER_SEC; |
| 385 | --sec; |
| 386 | } |
| 387 | ts->tv_sec = sec; |
| 388 | ts->tv_nsec = nsec; |
| 389 | } |
YOSHIFUJI Hideaki | 7c3f944 | 2008-04-21 19:45:12 -0700 | [diff] [blame] | 390 | EXPORT_SYMBOL(set_normalized_timespec); |
Thomas Gleixner | 753be62 | 2006-01-09 20:52:22 -0800 | [diff] [blame] | 391 | |
Thomas Gleixner | f8f46da | 2006-01-09 20:52:30 -0800 | [diff] [blame] | 392 | /** |
| 393 | * ns_to_timespec - Convert nanoseconds to timespec |
| 394 | * @nsec: the nanoseconds value to be converted |
| 395 | * |
| 396 | * Returns the timespec representation of the nsec parameter. |
| 397 | */ |
Roman Zippel | df869b6 | 2006-03-26 01:38:11 -0800 | [diff] [blame] | 398 | struct timespec ns_to_timespec(const s64 nsec) |
Thomas Gleixner | f8f46da | 2006-01-09 20:52:30 -0800 | [diff] [blame] | 399 | { |
| 400 | struct timespec ts; |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 401 | s32 rem; |
Thomas Gleixner | f8f46da | 2006-01-09 20:52:30 -0800 | [diff] [blame] | 402 | |
George Anzinger | 88fc389 | 2006-02-03 03:04:20 -0800 | [diff] [blame] | 403 | if (!nsec) |
| 404 | return (struct timespec) {0, 0}; |
| 405 | |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 406 | ts.tv_sec = div_s64_rem(nsec, NSEC_PER_SEC, &rem); |
| 407 | if (unlikely(rem < 0)) { |
| 408 | ts.tv_sec--; |
| 409 | rem += NSEC_PER_SEC; |
| 410 | } |
| 411 | ts.tv_nsec = rem; |
Thomas Gleixner | f8f46da | 2006-01-09 20:52:30 -0800 | [diff] [blame] | 412 | |
| 413 | return ts; |
| 414 | } |
Stephen Hemminger | 85795d6 | 2007-03-24 21:35:33 -0700 | [diff] [blame] | 415 | EXPORT_SYMBOL(ns_to_timespec); |
Thomas Gleixner | f8f46da | 2006-01-09 20:52:30 -0800 | [diff] [blame] | 416 | |
| 417 | /** |
| 418 | * ns_to_timeval - Convert nanoseconds to timeval |
| 419 | * @nsec: the nanoseconds value to be converted |
| 420 | * |
| 421 | * Returns the timeval representation of the nsec parameter. |
| 422 | */ |
Roman Zippel | df869b6 | 2006-03-26 01:38:11 -0800 | [diff] [blame] | 423 | struct timeval ns_to_timeval(const s64 nsec) |
Thomas Gleixner | f8f46da | 2006-01-09 20:52:30 -0800 | [diff] [blame] | 424 | { |
| 425 | struct timespec ts = ns_to_timespec(nsec); |
| 426 | struct timeval tv; |
| 427 | |
| 428 | tv.tv_sec = ts.tv_sec; |
| 429 | tv.tv_usec = (suseconds_t) ts.tv_nsec / 1000; |
| 430 | |
| 431 | return tv; |
| 432 | } |
Eric Dumazet | b7aa0bf | 2007-04-19 16:16:32 -0700 | [diff] [blame] | 433 | EXPORT_SYMBOL(ns_to_timeval); |
Thomas Gleixner | f8f46da | 2006-01-09 20:52:30 -0800 | [diff] [blame] | 434 | |
John Stultz | 49cd6f8 | 2014-07-16 21:03:59 +0000 | [diff] [blame] | 435 | #if BITS_PER_LONG == 32 |
| 436 | /** |
| 437 | * set_normalized_timespec - set timespec sec and nsec parts and normalize |
| 438 | * |
| 439 | * @ts: pointer to timespec variable to be set |
| 440 | * @sec: seconds to set |
| 441 | * @nsec: nanoseconds to set |
| 442 | * |
| 443 | * Set seconds and nanoseconds field of a timespec variable and |
| 444 | * normalize to the timespec storage format |
| 445 | * |
| 446 | * Note: The tv_nsec part is always in the range of |
| 447 | * 0 <= tv_nsec < NSEC_PER_SEC |
| 448 | * For negative values only the tv_sec field is negative ! |
| 449 | */ |
| 450 | void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec) |
| 451 | { |
| 452 | while (nsec >= NSEC_PER_SEC) { |
| 453 | /* |
| 454 | * The following asm() prevents the compiler from |
| 455 | * optimising this loop into a modulo operation. See |
| 456 | * also __iter_div_u64_rem() in include/linux/time.h |
| 457 | */ |
| 458 | asm("" : "+rm"(nsec)); |
| 459 | nsec -= NSEC_PER_SEC; |
| 460 | ++sec; |
| 461 | } |
| 462 | while (nsec < 0) { |
| 463 | asm("" : "+rm"(nsec)); |
| 464 | nsec += NSEC_PER_SEC; |
| 465 | --sec; |
| 466 | } |
| 467 | ts->tv_sec = sec; |
| 468 | ts->tv_nsec = nsec; |
| 469 | } |
| 470 | EXPORT_SYMBOL(set_normalized_timespec64); |
| 471 | |
| 472 | /** |
| 473 | * ns_to_timespec64 - Convert nanoseconds to timespec64 |
| 474 | * @nsec: the nanoseconds value to be converted |
| 475 | * |
| 476 | * Returns the timespec64 representation of the nsec parameter. |
| 477 | */ |
| 478 | struct timespec64 ns_to_timespec64(const s64 nsec) |
| 479 | { |
| 480 | struct timespec64 ts; |
| 481 | s32 rem; |
| 482 | |
| 483 | if (!nsec) |
| 484 | return (struct timespec64) {0, 0}; |
| 485 | |
| 486 | ts.tv_sec = div_s64_rem(nsec, NSEC_PER_SEC, &rem); |
| 487 | if (unlikely(rem < 0)) { |
| 488 | ts.tv_sec--; |
| 489 | rem += NSEC_PER_SEC; |
| 490 | } |
| 491 | ts.tv_nsec = rem; |
| 492 | |
| 493 | return ts; |
| 494 | } |
| 495 | EXPORT_SYMBOL(ns_to_timespec64); |
| 496 | #endif |
Nicholas Mc Guire | ca42aaf | 2015-05-18 14:19:13 +0200 | [diff] [blame] | 497 | /** |
| 498 | * msecs_to_jiffies: - convert milliseconds to jiffies |
| 499 | * @m: time in milliseconds |
| 500 | * |
| 501 | * conversion is done as follows: |
Ingo Molnar | 41cf544 | 2007-02-16 01:27:28 -0800 | [diff] [blame] | 502 | * |
| 503 | * - negative values mean 'infinite timeout' (MAX_JIFFY_OFFSET) |
| 504 | * |
| 505 | * - 'too large' values [that would result in larger than |
| 506 | * MAX_JIFFY_OFFSET values] mean 'infinite timeout' too. |
| 507 | * |
| 508 | * - all other values are converted to jiffies by either multiplying |
Nicholas Mc Guire | ca42aaf | 2015-05-18 14:19:13 +0200 | [diff] [blame] | 509 | * the input value by a factor or dividing it with a factor and |
| 510 | * handling any 32-bit overflows. |
| 511 | * for the details see __msecs_to_jiffies() |
Ingo Molnar | 41cf544 | 2007-02-16 01:27:28 -0800 | [diff] [blame] | 512 | * |
Nicholas Mc Guire | ca42aaf | 2015-05-18 14:19:13 +0200 | [diff] [blame] | 513 | * msecs_to_jiffies() checks for the passed in value being a constant |
| 514 | * via __builtin_constant_p() allowing gcc to eliminate most of the |
| 515 | * code, __msecs_to_jiffies() is called if the value passed does not |
| 516 | * allow constant folding and the actual conversion must be done at |
| 517 | * runtime. |
| 518 | * the _msecs_to_jiffies helpers are the HZ dependent conversion |
| 519 | * routines found in include/linux/jiffies.h |
Ingo Molnar | 41cf544 | 2007-02-16 01:27:28 -0800 | [diff] [blame] | 520 | */ |
Nicholas Mc Guire | ca42aaf | 2015-05-18 14:19:13 +0200 | [diff] [blame] | 521 | unsigned long __msecs_to_jiffies(const unsigned int m) |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 522 | { |
Ingo Molnar | 41cf544 | 2007-02-16 01:27:28 -0800 | [diff] [blame] | 523 | /* |
| 524 | * Negative value, means infinite timeout: |
| 525 | */ |
| 526 | if ((int)m < 0) |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 527 | return MAX_JIFFY_OFFSET; |
Nicholas Mc Guire | ca42aaf | 2015-05-18 14:19:13 +0200 | [diff] [blame] | 528 | return _msecs_to_jiffies(m); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 529 | } |
Nicholas Mc Guire | ca42aaf | 2015-05-18 14:19:13 +0200 | [diff] [blame] | 530 | EXPORT_SYMBOL(__msecs_to_jiffies); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 531 | |
Nicholas Mc Guire | ae60d6a | 2015-05-28 19:09:55 +0200 | [diff] [blame] | 532 | unsigned long __usecs_to_jiffies(const unsigned int u) |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 533 | { |
| 534 | if (u > jiffies_to_usecs(MAX_JIFFY_OFFSET)) |
| 535 | return MAX_JIFFY_OFFSET; |
Nicholas Mc Guire | ae60d6a | 2015-05-28 19:09:55 +0200 | [diff] [blame] | 536 | return _usecs_to_jiffies(u); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 537 | } |
Nicholas Mc Guire | ae60d6a | 2015-05-28 19:09:55 +0200 | [diff] [blame] | 538 | EXPORT_SYMBOL(__usecs_to_jiffies); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 539 | |
| 540 | /* |
| 541 | * The TICK_NSEC - 1 rounds up the value to the next resolution. Note |
| 542 | * that a remainder subtract here would not do the right thing as the |
| 543 | * resolution values don't fall on second boundries. I.e. the line: |
| 544 | * nsec -= nsec % TICK_NSEC; is NOT a correct resolution rounding. |
Andrew Hunter | d78c930 | 2014-09-04 14:17:16 -0700 | [diff] [blame] | 545 | * Note that due to the small error in the multiplier here, this |
| 546 | * rounding is incorrect for sufficiently large values of tv_nsec, but |
| 547 | * well formed timespecs should have tv_nsec < NSEC_PER_SEC, so we're |
| 548 | * OK. |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 549 | * |
| 550 | * Rather, we just shift the bits off the right. |
| 551 | * |
| 552 | * The >> (NSEC_JIFFIE_SC - SEC_JIFFIE_SC) converts the scaled nsec |
| 553 | * value to a scaled second value. |
| 554 | */ |
Andrew Hunter | d78c930 | 2014-09-04 14:17:16 -0700 | [diff] [blame] | 555 | static unsigned long |
Baolin Wang | 9ca3085 | 2015-07-29 20:18:31 +0800 | [diff] [blame] | 556 | __timespec64_to_jiffies(u64 sec, long nsec) |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 557 | { |
Andrew Hunter | d78c930 | 2014-09-04 14:17:16 -0700 | [diff] [blame] | 558 | nsec = nsec + TICK_NSEC - 1; |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 559 | |
| 560 | if (sec >= MAX_SEC_IN_JIFFIES){ |
| 561 | sec = MAX_SEC_IN_JIFFIES; |
| 562 | nsec = 0; |
| 563 | } |
Baolin Wang | 9ca3085 | 2015-07-29 20:18:31 +0800 | [diff] [blame] | 564 | return ((sec * SEC_CONVERSION) + |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 565 | (((u64)nsec * NSEC_CONVERSION) >> |
| 566 | (NSEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC; |
| 567 | |
| 568 | } |
Andrew Hunter | d78c930 | 2014-09-04 14:17:16 -0700 | [diff] [blame] | 569 | |
Baolin Wang | 9ca3085 | 2015-07-29 20:18:31 +0800 | [diff] [blame] | 570 | static unsigned long |
| 571 | __timespec_to_jiffies(unsigned long sec, long nsec) |
Andrew Hunter | d78c930 | 2014-09-04 14:17:16 -0700 | [diff] [blame] | 572 | { |
Baolin Wang | 9ca3085 | 2015-07-29 20:18:31 +0800 | [diff] [blame] | 573 | return __timespec64_to_jiffies((u64)sec, nsec); |
Andrew Hunter | d78c930 | 2014-09-04 14:17:16 -0700 | [diff] [blame] | 574 | } |
| 575 | |
Baolin Wang | 9ca3085 | 2015-07-29 20:18:31 +0800 | [diff] [blame] | 576 | unsigned long |
| 577 | timespec64_to_jiffies(const struct timespec64 *value) |
| 578 | { |
| 579 | return __timespec64_to_jiffies(value->tv_sec, value->tv_nsec); |
| 580 | } |
| 581 | EXPORT_SYMBOL(timespec64_to_jiffies); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 582 | |
| 583 | void |
Baolin Wang | 9ca3085 | 2015-07-29 20:18:31 +0800 | [diff] [blame] | 584 | jiffies_to_timespec64(const unsigned long jiffies, struct timespec64 *value) |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 585 | { |
| 586 | /* |
| 587 | * Convert jiffies to nanoseconds and separate with |
| 588 | * one divide. |
| 589 | */ |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 590 | u32 rem; |
| 591 | value->tv_sec = div_u64_rem((u64)jiffies * TICK_NSEC, |
| 592 | NSEC_PER_SEC, &rem); |
| 593 | value->tv_nsec = rem; |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 594 | } |
Baolin Wang | 9ca3085 | 2015-07-29 20:18:31 +0800 | [diff] [blame] | 595 | EXPORT_SYMBOL(jiffies_to_timespec64); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 596 | |
Andrew Hunter | d78c930 | 2014-09-04 14:17:16 -0700 | [diff] [blame] | 597 | /* |
| 598 | * We could use a similar algorithm to timespec_to_jiffies (with a |
| 599 | * different multiplier for usec instead of nsec). But this has a |
| 600 | * problem with rounding: we can't exactly add TICK_NSEC - 1 to the |
| 601 | * usec value, since it's not necessarily integral. |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 602 | * |
Andrew Hunter | d78c930 | 2014-09-04 14:17:16 -0700 | [diff] [blame] | 603 | * We could instead round in the intermediate scaled representation |
| 604 | * (i.e. in units of 1/2^(large scale) jiffies) but that's also |
| 605 | * perilous: the scaling introduces a small positive error, which |
| 606 | * combined with a division-rounding-upward (i.e. adding 2^(scale) - 1 |
| 607 | * units to the intermediate before shifting) leads to accidental |
| 608 | * overflow and overestimates. |
| 609 | * |
| 610 | * At the cost of one additional multiplication by a constant, just |
| 611 | * use the timespec implementation. |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 612 | */ |
| 613 | unsigned long |
| 614 | timeval_to_jiffies(const struct timeval *value) |
| 615 | { |
Andrew Hunter | d78c930 | 2014-09-04 14:17:16 -0700 | [diff] [blame] | 616 | return __timespec_to_jiffies(value->tv_sec, |
| 617 | value->tv_usec * NSEC_PER_USEC); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 618 | } |
Thomas Bittermann | 456a09d | 2007-04-04 22:20:54 +0200 | [diff] [blame] | 619 | EXPORT_SYMBOL(timeval_to_jiffies); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 620 | |
| 621 | void jiffies_to_timeval(const unsigned long jiffies, struct timeval *value) |
| 622 | { |
| 623 | /* |
| 624 | * Convert jiffies to nanoseconds and separate with |
| 625 | * one divide. |
| 626 | */ |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 627 | u32 rem; |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 628 | |
Roman Zippel | f8bd225 | 2008-05-01 04:34:31 -0700 | [diff] [blame] | 629 | value->tv_sec = div_u64_rem((u64)jiffies * TICK_NSEC, |
| 630 | NSEC_PER_SEC, &rem); |
| 631 | value->tv_usec = rem / NSEC_PER_USEC; |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 632 | } |
Thomas Bittermann | 456a09d | 2007-04-04 22:20:54 +0200 | [diff] [blame] | 633 | EXPORT_SYMBOL(jiffies_to_timeval); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 634 | |
| 635 | /* |
| 636 | * Convert jiffies/jiffies_64 to clock_t and back. |
| 637 | */ |
hank | cbbc719 | 2011-09-20 13:53:39 -0700 | [diff] [blame] | 638 | clock_t jiffies_to_clock_t(unsigned long x) |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 639 | { |
| 640 | #if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0 |
David Fries | 6ffc787 | 2008-02-06 01:38:04 -0800 | [diff] [blame] | 641 | # if HZ < USER_HZ |
| 642 | return x * (USER_HZ / HZ); |
| 643 | # else |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 644 | return x / (HZ / USER_HZ); |
David Fries | 6ffc787 | 2008-02-06 01:38:04 -0800 | [diff] [blame] | 645 | # endif |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 646 | #else |
Roman Zippel | 71abb3a | 2008-05-01 04:34:26 -0700 | [diff] [blame] | 647 | return div_u64((u64)x * TICK_NSEC, NSEC_PER_SEC / USER_HZ); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 648 | #endif |
| 649 | } |
| 650 | EXPORT_SYMBOL(jiffies_to_clock_t); |
| 651 | |
| 652 | unsigned long clock_t_to_jiffies(unsigned long x) |
| 653 | { |
| 654 | #if (HZ % USER_HZ)==0 |
| 655 | if (x >= ~0UL / (HZ / USER_HZ)) |
| 656 | return ~0UL; |
| 657 | return x * (HZ / USER_HZ); |
| 658 | #else |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 659 | /* Don't worry about loss of precision here .. */ |
| 660 | if (x >= ~0UL / HZ * USER_HZ) |
| 661 | return ~0UL; |
| 662 | |
| 663 | /* .. but do try to contain it here */ |
Roman Zippel | 71abb3a | 2008-05-01 04:34:26 -0700 | [diff] [blame] | 664 | return div_u64((u64)x * HZ, USER_HZ); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 665 | #endif |
| 666 | } |
| 667 | EXPORT_SYMBOL(clock_t_to_jiffies); |
| 668 | |
| 669 | u64 jiffies_64_to_clock_t(u64 x) |
| 670 | { |
| 671 | #if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0 |
David Fries | 6ffc787 | 2008-02-06 01:38:04 -0800 | [diff] [blame] | 672 | # if HZ < USER_HZ |
Roman Zippel | 71abb3a | 2008-05-01 04:34:26 -0700 | [diff] [blame] | 673 | x = div_u64(x * USER_HZ, HZ); |
Andrew Morton | ec03d70 | 2008-02-06 01:38:06 -0800 | [diff] [blame] | 674 | # elif HZ > USER_HZ |
Roman Zippel | 71abb3a | 2008-05-01 04:34:26 -0700 | [diff] [blame] | 675 | x = div_u64(x, HZ / USER_HZ); |
Andrew Morton | ec03d70 | 2008-02-06 01:38:06 -0800 | [diff] [blame] | 676 | # else |
| 677 | /* Nothing to do */ |
David Fries | 6ffc787 | 2008-02-06 01:38:04 -0800 | [diff] [blame] | 678 | # endif |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 679 | #else |
| 680 | /* |
| 681 | * There are better ways that don't overflow early, |
| 682 | * but even this doesn't overflow in hundreds of years |
| 683 | * in 64 bits, so.. |
| 684 | */ |
Roman Zippel | 71abb3a | 2008-05-01 04:34:26 -0700 | [diff] [blame] | 685 | x = div_u64(x * TICK_NSEC, (NSEC_PER_SEC / USER_HZ)); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 686 | #endif |
| 687 | return x; |
| 688 | } |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 689 | EXPORT_SYMBOL(jiffies_64_to_clock_t); |
| 690 | |
| 691 | u64 nsec_to_clock_t(u64 x) |
| 692 | { |
| 693 | #if (NSEC_PER_SEC % USER_HZ) == 0 |
Roman Zippel | 71abb3a | 2008-05-01 04:34:26 -0700 | [diff] [blame] | 694 | return div_u64(x, NSEC_PER_SEC / USER_HZ); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 695 | #elif (USER_HZ % 512) == 0 |
Roman Zippel | 71abb3a | 2008-05-01 04:34:26 -0700 | [diff] [blame] | 696 | return div_u64(x * USER_HZ / 512, NSEC_PER_SEC / 512); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 697 | #else |
| 698 | /* |
| 699 | * max relative error 5.7e-8 (1.8s per year) for USER_HZ <= 1024, |
| 700 | * overflow after 64.99 years. |
| 701 | * exact for HZ=60, 72, 90, 120, 144, 180, 300, 600, 900, ... |
| 702 | */ |
Roman Zippel | 71abb3a | 2008-05-01 04:34:26 -0700 | [diff] [blame] | 703 | return div_u64(x * 9, (9ull * NSEC_PER_SEC + (USER_HZ / 2)) / USER_HZ); |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 704 | #endif |
Ingo Molnar | 8b9365d | 2007-02-16 01:27:27 -0800 | [diff] [blame] | 705 | } |
| 706 | |
Frederic Weisbecker | e7038f8 | 2017-01-31 04:09:17 +0100 | [diff] [blame] | 707 | u64 jiffies64_to_nsecs(u64 j) |
| 708 | { |
| 709 | #if !(NSEC_PER_SEC % HZ) |
| 710 | return (NSEC_PER_SEC / HZ) * j; |
| 711 | # else |
| 712 | return div_u64(j * HZ_TO_NSEC_NUM, HZ_TO_NSEC_DEN); |
| 713 | #endif |
| 714 | } |
| 715 | EXPORT_SYMBOL(jiffies64_to_nsecs); |
| 716 | |
Hidetoshi Seto | b7b20df9 | 2009-11-26 14:49:27 +0900 | [diff] [blame] | 717 | /** |
Venkatesh Pallipadi | a1dabb6 | 2010-12-21 17:09:01 -0800 | [diff] [blame] | 718 | * nsecs_to_jiffies64 - Convert nsecs in u64 to jiffies64 |
Hidetoshi Seto | b7b20df9 | 2009-11-26 14:49:27 +0900 | [diff] [blame] | 719 | * |
| 720 | * @n: nsecs in u64 |
| 721 | * |
| 722 | * Unlike {m,u}secs_to_jiffies, type of input is not unsigned int but u64. |
| 723 | * And this doesn't return MAX_JIFFY_OFFSET since this function is designed |
| 724 | * for scheduler, not for use in device drivers to calculate timeout value. |
| 725 | * |
| 726 | * note: |
| 727 | * NSEC_PER_SEC = 10^9 = (5^9 * 2^9) = (1953125 * 512) |
| 728 | * ULLONG_MAX ns = 18446744073.709551615 secs = about 584 years |
| 729 | */ |
Venkatesh Pallipadi | a1dabb6 | 2010-12-21 17:09:01 -0800 | [diff] [blame] | 730 | u64 nsecs_to_jiffies64(u64 n) |
Hidetoshi Seto | b7b20df9 | 2009-11-26 14:49:27 +0900 | [diff] [blame] | 731 | { |
| 732 | #if (NSEC_PER_SEC % HZ) == 0 |
| 733 | /* Common case, HZ = 100, 128, 200, 250, 256, 500, 512, 1000 etc. */ |
| 734 | return div_u64(n, NSEC_PER_SEC / HZ); |
| 735 | #elif (HZ % 512) == 0 |
| 736 | /* overflow after 292 years if HZ = 1024 */ |
| 737 | return div_u64(n * HZ / 512, NSEC_PER_SEC / 512); |
| 738 | #else |
| 739 | /* |
| 740 | * Generic case - optimized for cases where HZ is a multiple of 3. |
| 741 | * overflow after 64.99 years, exact for HZ = 60, 72, 90, 120 etc. |
| 742 | */ |
| 743 | return div_u64(n * 9, (9ull * NSEC_PER_SEC + HZ / 2) / HZ); |
| 744 | #endif |
| 745 | } |
Daniel Vetter | 7bd0e22 | 2014-12-04 11:12:54 +0100 | [diff] [blame] | 746 | EXPORT_SYMBOL(nsecs_to_jiffies64); |
Hidetoshi Seto | b7b20df9 | 2009-11-26 14:49:27 +0900 | [diff] [blame] | 747 | |
Venkatesh Pallipadi | a1dabb6 | 2010-12-21 17:09:01 -0800 | [diff] [blame] | 748 | /** |
| 749 | * nsecs_to_jiffies - Convert nsecs in u64 to jiffies |
| 750 | * |
| 751 | * @n: nsecs in u64 |
| 752 | * |
| 753 | * Unlike {m,u}secs_to_jiffies, type of input is not unsigned int but u64. |
| 754 | * And this doesn't return MAX_JIFFY_OFFSET since this function is designed |
| 755 | * for scheduler, not for use in device drivers to calculate timeout value. |
| 756 | * |
| 757 | * note: |
| 758 | * NSEC_PER_SEC = 10^9 = (5^9 * 2^9) = (1953125 * 512) |
| 759 | * ULLONG_MAX ns = 18446744073.709551615 secs = about 584 years |
| 760 | */ |
| 761 | unsigned long nsecs_to_jiffies(u64 n) |
| 762 | { |
| 763 | return (unsigned long)nsecs_to_jiffies64(n); |
| 764 | } |
Thomas Gleixner | d560fed | 2014-07-16 21:04:31 +0000 | [diff] [blame] | 765 | EXPORT_SYMBOL_GPL(nsecs_to_jiffies); |
Venkatesh Pallipadi | a1dabb6 | 2010-12-21 17:09:01 -0800 | [diff] [blame] | 766 | |
Thomas Gleixner | df0cc05 | 2008-08-31 08:09:53 -0700 | [diff] [blame] | 767 | /* |
| 768 | * Add two timespec values and do a safety check for overflow. |
| 769 | * It's assumed that both values are valid (>= 0) |
| 770 | */ |
| 771 | struct timespec timespec_add_safe(const struct timespec lhs, |
| 772 | const struct timespec rhs) |
| 773 | { |
| 774 | struct timespec res; |
| 775 | |
| 776 | set_normalized_timespec(&res, lhs.tv_sec + rhs.tv_sec, |
| 777 | lhs.tv_nsec + rhs.tv_nsec); |
| 778 | |
| 779 | if (res.tv_sec < lhs.tv_sec || res.tv_sec < rhs.tv_sec) |
| 780 | res.tv_sec = TIME_T_MAX; |
| 781 | |
| 782 | return res; |
| 783 | } |
Deepa Dinamani | bc2c53e | 2016-05-19 17:09:02 -0700 | [diff] [blame] | 784 | |
Deepa Dinamani | bc2c53e | 2016-05-19 17:09:02 -0700 | [diff] [blame] | 785 | /* |
| 786 | * Add two timespec64 values and do a safety check for overflow. |
| 787 | * It's assumed that both values are valid (>= 0). |
| 788 | * And, each timespec64 is in normalized form. |
| 789 | */ |
| 790 | struct timespec64 timespec64_add_safe(const struct timespec64 lhs, |
| 791 | const struct timespec64 rhs) |
| 792 | { |
| 793 | struct timespec64 res; |
| 794 | |
Vegard Nossum | 469e857f3 | 2016-08-12 20:14:09 +0200 | [diff] [blame] | 795 | set_normalized_timespec64(&res, (timeu64_t) lhs.tv_sec + rhs.tv_sec, |
Deepa Dinamani | bc2c53e | 2016-05-19 17:09:02 -0700 | [diff] [blame] | 796 | lhs.tv_nsec + rhs.tv_nsec); |
| 797 | |
| 798 | if (unlikely(res.tv_sec < lhs.tv_sec || res.tv_sec < rhs.tv_sec)) { |
| 799 | res.tv_sec = TIME64_MAX; |
| 800 | res.tv_nsec = 0; |
| 801 | } |
| 802 | |
| 803 | return res; |
| 804 | } |