Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
d11f147850
NetBSD/sys/kern/kern_time.c
chs e07f0b9362 eliminate uvm_useracc() in favor of checking the return value of 
copyin() or copyout().

uvm_useracc() tells us whether the mapping permissions allow access to
the desired part of an address space, and many callers assume that
this is the same as knowing whether an attempt to access that part of
the address space will succeed.  however, access to user space can
fail for reasons other than insufficient permission, most notably that
paging in any non-resident data can fail due to i/o errors.  most of
the callers of uvm_useracc() make the above incorrect assumption.  the
rest are all misguided optimizations, which optimize for the case
where an operation will fail.  we'd rather optimize for operations
succeeding, in which case we should just attempt the access and handle
failures due to insufficient permissions the same way we handle i/o
errors.  since there appear to be no good uses of uvm_useracc(), we'll
just remove it.
2003-11-13 03:09:28 +00:00

1349 lines
35 KiB
C
Raw Blame History

/* $NetBSD: kern_time.c,v 1.79 2003/11/13 03:09:30 chs Exp $ */
/*-
* Copyright (c) 2000 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christopher G. Demetriou.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)kern_time.c 8.4 (Berkeley) 5/26/95
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: kern_time.c,v 1.79 2003/11/13 03:09:30 chs Exp $");
#include "fs_nfs.h"
#include "opt_nfs.h"
#include "opt_nfsserver.h"
#include <sys/param.h>
#include <sys/resourcevar.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/sa.h>
#include <sys/savar.h>
#include <sys/vnode.h>
#include <sys/signalvar.h>
#include <sys/syslog.h>
#include <sys/mount.h>
#include <sys/syscallargs.h>
#include <uvm/uvm_extern.h>
#if defined(NFS) || defined(NFSSERVER)
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfs/nfs_var.h>
#endif
#include <machine/cpu.h>
static void timerupcall(struct lwp *, void *);
/* Time of day and interval timer support.
*
* These routines provide the kernel entry points to get and set
* the time-of-day and per-process interval timers. Subroutines
* here provide support for adding and subtracting timeval structures
* and decrementing interval timers, optionally reloading the interval
* timers when they expire.
*/
/* This function is used by clock_settime and settimeofday */
int
settime(struct timeval *tv)
{
struct timeval delta;
struct cpu_info *ci;
int s;
/* WHAT DO WE DO ABOUT PENDING REAL-TIME TIMEOUTS??? */
s = splclock();
timersub(tv, &time, &delta);
if ((delta.tv_sec < 0 || delta.tv_usec < 0) && securelevel > 1) {
splx(s);
return (EPERM);
}
#ifdef notyet
if ((delta.tv_sec < 86400) && securelevel > 0) {
splx(s);
return (EPERM);
}
#endif
time = *tv;
(void) spllowersoftclock();
timeradd(&boottime, &delta, &boottime);
/*
* XXXSMP
* This is wrong. We should traverse a list of all
* CPUs and add the delta to the runtime of those
* CPUs which have a process on them.
*/
ci = curcpu();
timeradd(&ci->ci_schedstate.spc_runtime, &delta,
&ci->ci_schedstate.spc_runtime);
# if (defined(NFS) && !defined (NFS_V2_ONLY)) || defined(NFSSERVER)
nqnfs_lease_updatetime(delta.tv_sec);
# endif
splx(s);
resettodr();
return (0);
}
/* ARGSUSED */
int
sys_clock_gettime(struct lwp *l, void *v, register_t *retval)
{
struct sys_clock_gettime_args /* {
syscallarg(clockid_t) clock_id;
syscallarg(struct timespec *) tp;
} */ *uap = v;
clockid_t clock_id;
struct timeval atv;
struct timespec ats;
int s;
clock_id = SCARG(uap, clock_id);
switch (clock_id) {
case CLOCK_REALTIME:
microtime(&atv);
TIMEVAL_TO_TIMESPEC(&atv,&ats);
break;
case CLOCK_MONOTONIC:
/* XXX "hz" granularity */
s = splclock();
atv = mono_time;
splx(s);
TIMEVAL_TO_TIMESPEC(&atv,&ats);
break;
default:
return (EINVAL);
}
return copyout(&ats, SCARG(uap, tp), sizeof(ats));
}
/* ARGSUSED */
int
sys_clock_settime(l, v, retval)
struct lwp *l;
void *v;
register_t *retval;
{
struct sys_clock_settime_args /* {
syscallarg(clockid_t) clock_id;
syscallarg(const struct timespec *) tp;
} */ *uap = v;
struct proc *p = l->l_proc;
int error;
if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
return (error);
return (clock_settime1(SCARG(uap, clock_id), SCARG(uap, tp)));
}
int
clock_settime1(clock_id, tp)
clockid_t clock_id;
const struct timespec *tp;
{
struct timespec ats;
struct timeval atv;
int error;
if ((error = copyin(tp, &ats, sizeof(ats))) != 0)
return (error);
switch (clock_id) {
case CLOCK_REALTIME:
TIMESPEC_TO_TIMEVAL(&atv, &ats);
if ((error = settime(&atv)) != 0)
return (error);
break;
case CLOCK_MONOTONIC:
return (EINVAL); /* read-only clock */
default:
return (EINVAL);
}
return 0;
}
int
sys_clock_getres(struct lwp *l, void *v, register_t *retval)
{
struct sys_clock_getres_args /* {
syscallarg(clockid_t) clock_id;
syscallarg(struct timespec *) tp;
} */ *uap = v;
clockid_t clock_id;
struct timespec ts;
int error = 0;
clock_id = SCARG(uap, clock_id);
switch (clock_id) {
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
ts.tv_sec = 0;
ts.tv_nsec = 1000000000 / hz;
break;
default:
return (EINVAL);
}
if (SCARG(uap, tp))
error = copyout(&ts, SCARG(uap, tp), sizeof(ts));
return error;
}
/* ARGSUSED */
int
sys_nanosleep(struct lwp *l, void *v, register_t *retval)
{
static int nanowait;
struct sys_nanosleep_args/* {
syscallarg(struct timespec *) rqtp;
syscallarg(struct timespec *) rmtp;
} */ *uap = v;
struct timespec rqt;
struct timespec rmt;
struct timeval atv, utv;
int error, s, timo;
error = copyin((caddr_t)SCARG(uap, rqtp), (caddr_t)&rqt,
sizeof(struct timespec));
if (error)
return (error);
TIMESPEC_TO_TIMEVAL(&atv,&rqt)
if (itimerfix(&atv) || atv.tv_sec > 1000000000)
return (EINVAL);
s = splclock();
timeradd(&atv,&time,&atv);
timo = hzto(&atv);
/*
* Avoid inadvertantly sleeping forever
*/
if (timo == 0)
timo = 1;
splx(s);
error = tsleep(&nanowait, PWAIT | PCATCH, "nanosleep", timo);
if (error == ERESTART)
error = EINTR;
if (error == EWOULDBLOCK)
error = 0;
if (SCARG(uap, rmtp)) {
int error;
s = splclock();
utv = time;
splx(s);
timersub(&atv, &utv, &utv);
if (utv.tv_sec < 0)
timerclear(&utv);
TIMEVAL_TO_TIMESPEC(&utv,&rmt);
error = copyout((caddr_t)&rmt, (caddr_t)SCARG(uap,rmtp),
sizeof(rmt));
if (error)
return (error);
}
return error;
}
/* ARGSUSED */
int
sys_gettimeofday(struct lwp *l, void *v, register_t *retval)
{
struct sys_gettimeofday_args /* {
syscallarg(struct timeval *) tp;
syscallarg(struct timezone *) tzp;
} */ *uap = v;
struct timeval atv;
int error = 0;
struct timezone tzfake;
if (SCARG(uap, tp)) {
microtime(&atv);
error = copyout(&atv, SCARG(uap, tp), sizeof(atv));
if (error)
return (error);
}
if (SCARG(uap, tzp)) {
/*
* NetBSD has no kernel notion of time zone, so we just
* fake up a timezone struct and return it if demanded.
*/
tzfake.tz_minuteswest = 0;
tzfake.tz_dsttime = 0;
error = copyout(&tzfake, SCARG(uap, tzp), sizeof(tzfake));
}
return (error);
}
/* ARGSUSED */
int
sys_settimeofday(struct lwp *l, void *v, register_t *retval)
{
struct sys_settimeofday_args /* {
syscallarg(const struct timeval *) tv;
syscallarg(const struct timezone *) tzp;
} */ *uap = v;
struct proc *p = l->l_proc;
int error;
if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
return (error);
return settimeofday1(SCARG(uap, tv), SCARG(uap, tzp), p);
}
int
settimeofday1(utv, utzp, p)
const struct timeval *utv;
const struct timezone *utzp;
struct proc *p;
{
struct timeval atv;
struct timezone atz;
struct timeval *tv = NULL;
struct timezone *tzp = NULL;
int error;
/* Verify all parameters before changing time. */
if (utv) {
if ((error = copyin(utv, &atv, sizeof(atv))) != 0)
return (error);
tv = &atv;
}
/* XXX since we don't use tz, probably no point in doing copyin. */
if (utzp) {
if ((error = copyin(utzp, &atz, sizeof(atz))) != 0)
return (error);
tzp = &atz;
}
if (tv)
if ((error = settime(tv)) != 0)
return (error);
/*
* NetBSD has no kernel notion of time zone, and only an
* obsolete program would try to set it, so we log a warning.
*/
if (tzp)
log(LOG_WARNING, "pid %d attempted to set the "
"(obsolete) kernel time zone\n", p->p_pid);
return (0);
}
int tickdelta; /* current clock skew, us. per tick */
long timedelta; /* unapplied time correction, us. */
long bigadj = 1000000; /* use 10x skew above bigadj us. */
int time_adjusted; /* set if an adjustment is made */
/* ARGSUSED */
int
sys_adjtime(struct lwp *l, void *v, register_t *retval)
{
struct sys_adjtime_args /* {
syscallarg(const struct timeval *) delta;
syscallarg(struct timeval *) olddelta;
} */ *uap = v;
struct proc *p = l->l_proc;
int error;
if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
return (error);
return adjtime1(SCARG(uap, delta), SCARG(uap, olddelta), p);
}
int
adjtime1(delta, olddelta, p)
const struct timeval *delta;
struct timeval *olddelta;
struct proc *p;
{
struct timeval atv;
long ndelta, ntickdelta, odelta;
int error;
int s;
error = copyin(delta, &atv, sizeof(struct timeval));
if (error)
return (error);
/*
* Compute the total correction and the rate at which to apply it.
* Round the adjustment down to a whole multiple of the per-tick
* delta, so that after some number of incremental changes in
* hardclock(), tickdelta will become zero, lest the correction
* overshoot and start taking us away from the desired final time.
*/
ndelta = atv.tv_sec * 1000000 + atv.tv_usec;
if (ndelta > bigadj || ndelta < -bigadj)
ntickdelta = 10 * tickadj;
else
ntickdelta = tickadj;
if (ndelta % ntickdelta)
ndelta = ndelta / ntickdelta * ntickdelta;
/*
* To make hardclock()'s job easier, make the per-tick delta negative
* if we want time to run slower; then hardclock can simply compute
* tick + tickdelta, and subtract tickdelta from timedelta.
*/
if (ndelta < 0)
ntickdelta = -ntickdelta;
if (ndelta != 0)
/* We need to save the system clock time during shutdown */
time_adjusted |= 1;
s = splclock();
odelta = timedelta;
timedelta = ndelta;
tickdelta = ntickdelta;
splx(s);
if (olddelta) {
atv.tv_sec = odelta / 1000000;
atv.tv_usec = odelta % 1000000;
error = copyout(&atv, olddelta, sizeof(struct timeval));
}
return error;
}
/*
* Interval timer support. Both the BSD getitimer() family and the POSIX
* timer_*() family of routines are supported.
*
* All timers are kept in an array pointed to by p_timers, which is
* allocated on demand - many processes don't use timers at all. The
* first three elements in this array are reserved for the BSD timers:
* element 0 is ITIMER_REAL, element 1 is ITIMER_VIRTUAL, and element
* 2 is ITIMER_PROF. The rest may be allocated by the timer_create()
* syscall.
*
* Realtime timers are kept in the ptimer structure as an absolute
* time; virtual time timers are kept as a linked list of deltas.
* Virtual time timers are processed in the hardclock() routine of
* kern_clock.c. The real time timer is processed by a callout
* routine, called from the softclock() routine. Since a callout may
* be delayed in real time due to interrupt processing in the system,
* it is possible for the real time timeout routine (realtimeexpire,
* given below), to be delayed in real time past when it is supposed
* to occur. It does not suffice, therefore, to reload the real timer
* .it_value from the real time timers .it_interval. Rather, we
* compute the next time in absolute time the timer should go off. */
/* Allocate a POSIX realtime timer. */
int
sys_timer_create(struct lwp *l, void *v, register_t *retval)
{
struct sys_timer_create_args /* {
syscallarg(clockid_t) clock_id;
syscallarg(struct sigevent *) evp;
syscallarg(timer_t *) timerid;
} */ *uap = v;
struct proc *p = l->l_proc;
clockid_t id;
struct sigevent *evp;
struct ptimer *pt;
timer_t timerid;
int error;
id = SCARG(uap, clock_id);
if (id < CLOCK_REALTIME ||
id > CLOCK_PROF)
return (EINVAL);
if (p->p_timers == NULL)
timers_alloc(p);
/* Find a free timer slot, skipping those reserved for setitimer(). */
for (timerid = 3; timerid < TIMER_MAX; timerid++)
if (p->p_timers->pts_timers[timerid] == NULL)
break;
if (timerid == TIMER_MAX)
return EAGAIN;
pt = pool_get(&ptimer_pool, PR_WAITOK);
evp = SCARG(uap, evp);
if (evp) {
if (((error =
copyin(evp, &pt->pt_ev, sizeof (pt->pt_ev))) != 0) ||
((pt->pt_ev.sigev_notify < SIGEV_NONE) ||
(pt->pt_ev.sigev_notify > SIGEV_SA))) {
pool_put(&ptimer_pool, pt);
return (error ? error : EINVAL);
}
} else {
pt->pt_ev.sigev_notify = SIGEV_SIGNAL;
switch (id) {
case CLOCK_REALTIME:
pt->pt_ev.sigev_signo = SIGALRM;
break;
case CLOCK_VIRTUAL:
pt->pt_ev.sigev_signo = SIGVTALRM;
break;
case CLOCK_PROF:
pt->pt_ev.sigev_signo = SIGPROF;
break;
}
pt->pt_ev.sigev_value.sival_int = timerid;
}
pt->pt_info.ksi_signo = pt->pt_ev.sigev_signo;
pt->pt_info.ksi_errno = 0;
pt->pt_info.ksi_code = 0;
pt->pt_info.ksi_pid = p->p_pid;
pt->pt_info.ksi_uid = p->p_cred->p_ruid;
pt->pt_info.ksi_sigval = pt->pt_ev.sigev_value;
pt->pt_type = id;
pt->pt_proc = p;
pt->pt_overruns = 0;
pt->pt_poverruns = 0;
pt->pt_entry = timerid;
timerclear(&pt->pt_time.it_value);
if (id == CLOCK_REALTIME)
callout_init(&pt->pt_ch);
else
pt->pt_active = 0;
p->p_timers->pts_timers[timerid] = pt;
return copyout(&timerid, SCARG(uap, timerid), sizeof(timerid));
}
/* Delete a POSIX realtime timer */
int
sys_timer_delete(struct lwp *l, void *v, register_t *retval)
{
struct sys_timer_delete_args /* {
syscallarg(timer_t) timerid;
} */ *uap = v;
struct proc *p = l->l_proc;
timer_t timerid;
struct ptimer *pt, *ptn;
int s;
timerid = SCARG(uap, timerid);
if ((p->p_timers == NULL) ||
(timerid < 2) || (timerid >= TIMER_MAX) ||
((pt = p->p_timers->pts_timers[timerid]) == NULL))
return (EINVAL);
if (pt->pt_type == CLOCK_REALTIME)
callout_stop(&pt->pt_ch);
else if (pt->pt_active) {
s = splclock();
ptn = LIST_NEXT(pt, pt_list);
LIST_REMOVE(pt, pt_list);
for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list))
timeradd(&pt->pt_time.it_value, &ptn->pt_time.it_value,
&ptn->pt_time.it_value);
splx(s);
}
p->p_timers->pts_timers[timerid] = NULL;
pool_put(&ptimer_pool, pt);
return (0);
}
/*
* Set up the given timer. The value in pt->pt_time.it_value is taken
* to be an absolute time for CLOCK_REALTIME timers and a relative
* time for virtual timers.
* Must be called at splclock().
*/
void
timer_settime(struct ptimer *pt)
{
struct ptimer *ptn, *pptn;
struct ptlist *ptl;
if (pt->pt_type == CLOCK_REALTIME) {
callout_stop(&pt->pt_ch);
if (timerisset(&pt->pt_time.it_value)) {
/*
* Don't need to check hzto() return value, here.
* callout_reset() does it for us.
*/
callout_reset(&pt->pt_ch, hzto(&pt->pt_time.it_value),
realtimerexpire, pt);
}
} else {
if (pt->pt_active) {
ptn = LIST_NEXT(pt, pt_list);
LIST_REMOVE(pt, pt_list);
for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list))
timeradd(&pt->pt_time.it_value,
&ptn->pt_time.it_value,
&ptn->pt_time.it_value);
}
if (timerisset(&pt->pt_time.it_value)) {
if (pt->pt_type == CLOCK_VIRTUAL)
ptl = &pt->pt_proc->p_timers->pts_virtual;
else
ptl = &pt->pt_proc->p_timers->pts_prof;
for (ptn = LIST_FIRST(ptl), pptn = NULL;
ptn && timercmp(&pt->pt_time.it_value,
&ptn->pt_time.it_value, >);
pptn = ptn, ptn = LIST_NEXT(ptn, pt_list))
timersub(&pt->pt_time.it_value,
&ptn->pt_time.it_value,
&pt->pt_time.it_value);
if (pptn)
LIST_INSERT_AFTER(pptn, pt, pt_list);
else
LIST_INSERT_HEAD(ptl, pt, pt_list);
for ( ; ptn ; ptn = LIST_NEXT(ptn, pt_list))
timersub(&ptn->pt_time.it_value,
&pt->pt_time.it_value,
&ptn->pt_time.it_value);
pt->pt_active = 1;
} else
pt->pt_active = 0;
}
}
void
timer_gettime(struct ptimer *pt, struct itimerval *aitv)
{
struct ptimer *ptn;
*aitv = pt->pt_time;
if (pt->pt_type == CLOCK_REALTIME) {
/*
* Convert from absolute to relative time in .it_value
* part of real time timer. If time for real time
* timer has passed return 0, else return difference
* between current time and time for the timer to go
* off.
*/
if (timerisset(&aitv->it_value)) {
if (timercmp(&aitv->it_value, &time, <))
timerclear(&aitv->it_value);
else
timersub(&aitv->it_value, &time,
&aitv->it_value);
}
} else if (pt->pt_active) {
if (pt->pt_type == CLOCK_VIRTUAL)
ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_virtual);
else
ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_prof);
for ( ; ptn && ptn != pt; ptn = LIST_NEXT(ptn, pt_list))
timeradd(&aitv->it_value,
&ptn->pt_time.it_value, &aitv->it_value);
KASSERT(ptn != NULL); /* pt should be findable on the list */
} else
timerclear(&aitv->it_value);
}
/* Set and arm a POSIX realtime timer */
int
sys_timer_settime(struct lwp *l, void *v, register_t *retval)
{
struct sys_timer_settime_args /* {
syscallarg(timer_t) timerid;
syscallarg(int) flags;
syscallarg(const struct itimerspec *) value;
syscallarg(struct itimerspec *) ovalue;
} */ *uap = v;
struct proc *p = l->l_proc;
int error, s, timerid;
struct itimerval val, oval;
struct itimerspec value, ovalue;
struct ptimer *pt;
timerid = SCARG(uap, timerid);
if ((p->p_timers == NULL) ||
(timerid < 2) || (timerid >= TIMER_MAX) ||
((pt = p->p_timers->pts_timers[timerid]) == NULL))
return (EINVAL);
if ((error = copyin(SCARG(uap, value), &value,
sizeof(struct itimerspec))) != 0)
return (error);
TIMESPEC_TO_TIMEVAL(&val.it_value, &value.it_value);
TIMESPEC_TO_TIMEVAL(&val.it_interval, &value.it_interval);
if (itimerfix(&val.it_value) || itimerfix(&val.it_interval))
return (EINVAL);
oval = pt->pt_time;
pt->pt_time = val;
s = splclock();
/*
* If we've been passed a relative time for a realtime timer,
* convert it to absolute; if an absolute time for a virtual
* timer, convert it to relative and make sure we don't set it
* to zero, which would cancel the timer, or let it go
* negative, which would confuse the comparison tests.
*/
if (timerisset(&pt->pt_time.it_value)) {
if (pt->pt_type == CLOCK_REALTIME) {
if ((SCARG(uap, flags) & TIMER_ABSTIME) == 0)
timeradd(&pt->pt_time.it_value, &time,
&pt->pt_time.it_value);
} else {
if ((SCARG(uap, flags) & TIMER_ABSTIME) != 0) {
timersub(&pt->pt_time.it_value, &time,
&pt->pt_time.it_value);
if (!timerisset(&pt->pt_time.it_value) ||
pt->pt_time.it_value.tv_sec < 0) {
pt->pt_time.it_value.tv_sec = 0;
pt->pt_time.it_value.tv_usec = 1;
}
}
}
}
timer_settime(pt);
splx(s);
if (SCARG(uap, ovalue)) {
TIMEVAL_TO_TIMESPEC(&oval.it_value, &ovalue.it_value);
TIMEVAL_TO_TIMESPEC(&oval.it_interval, &ovalue.it_interval);
return copyout(&ovalue, SCARG(uap, ovalue),
sizeof(struct itimerspec));
}
return (0);
}
/* Return the time remaining until a POSIX timer fires. */
int
sys_timer_gettime(struct lwp *l, void *v, register_t *retval)
{
struct sys_timer_gettime_args /* {
syscallarg(timer_t) timerid;
syscallarg(struct itimerspec *) value;
} */ *uap = v;
struct itimerval aitv;
struct itimerspec its;
struct proc *p = l->l_proc;
int s, timerid;
struct ptimer *pt;
timerid = SCARG(uap, timerid);
if ((p->p_timers == NULL) ||
(timerid < 2) || (timerid >= TIMER_MAX) ||
((pt = p->p_timers->pts_timers[timerid]) == NULL))
return (EINVAL);
s = splclock();
timer_gettime(pt, &aitv);
splx(s);
TIMEVAL_TO_TIMESPEC(&aitv.it_interval, &its.it_interval);
TIMEVAL_TO_TIMESPEC(&aitv.it_value, &its.it_value);
return copyout(&its, SCARG(uap, value), sizeof(its));
}
/*
* Return the count of the number of times a periodic timer expired
* while a notification was already pending. The counter is reset when
* a timer expires and a notification can be posted.
*/
int
sys_timer_getoverrun(struct lwp *l, void *v, register_t *retval)
{
struct sys_timer_getoverrun_args /* {
syscallarg(timer_t) timerid;
} */ *uap = v;
struct proc *p = l->l_proc;
int timerid;
struct ptimer *pt;
timerid = SCARG(uap, timerid);
if ((p->p_timers == NULL) ||
(timerid < 2) || (timerid >= TIMER_MAX) ||
((pt = p->p_timers->pts_timers[timerid]) == NULL))
return (EINVAL);
*retval = pt->pt_poverruns;
return (0);
}
/* Glue function that triggers an upcall; called from userret(). */
static void
timerupcall(struct lwp *l, void *arg)
{
struct ptimers *pt = (struct ptimers *)arg;
unsigned int i, fired, done;
extern struct pool siginfo_pool; /* XXX Ew. */
KERNEL_PROC_LOCK(l);
{
struct proc *p = l->l_proc;
struct sadata *sa = p->p_sa;
/* Bail out if we do not own the virtual processor */
if (sa->sa_vp != l) {
KERNEL_PROC_UNLOCK(l);
return ;
}
}
fired = pt->pts_fired;
done = 0;
while ((i = ffs(fired)) != 0) {
siginfo_t *si;
int mask = 1 << --i;
int f;
f = l->l_flag & L_SA;
l->l_flag &= ~L_SA;
si = pool_get(&siginfo_pool, PR_WAITOK);
si->_info = pt->pts_timers[i]->pt_info.ksi_info;
if (sa_upcall(l, SA_UPCALL_SIGEV | SA_UPCALL_DEFER, NULL, l,
sizeof(*si), si) == 0)
done |= mask;
fired &= ~mask;
l->l_flag |= f;
}
pt->pts_fired &= ~done;
if (pt->pts_fired == 0)
l->l_proc->p_userret = NULL;
KERNEL_PROC_UNLOCK(l);
}
/*
* Real interval timer expired:
* send process whose timer expired an alarm signal.
* If time is not set up to reload, then just return.
* Else compute next time timer should go off which is > current time.
* This is where delay in processing this timeout causes multiple
* SIGALRM calls to be compressed into one.
*/
void
realtimerexpire(void *arg)
{
struct ptimer *pt;
int s;
pt = (struct ptimer *)arg;
itimerfire(pt);
if (!timerisset(&pt->pt_time.it_interval)) {
timerclear(&pt->pt_time.it_value);
return;
}
for (;;) {
s = splclock();
timeradd(&pt->pt_time.it_value,
&pt->pt_time.it_interval, &pt->pt_time.it_value);
if (timercmp(&pt->pt_time.it_value, &time, >)) {
/*
* Don't need to check hzto() return value, here.
* callout_reset() does it for us.
*/
callout_reset(&pt->pt_ch, hzto(&pt->pt_time.it_value),
realtimerexpire, pt);
splx(s);
return;
}
splx(s);
pt->pt_overruns++;
}
}
/* BSD routine to get the value of an interval timer. */
/* ARGSUSED */
int
sys_getitimer(struct lwp *l, void *v, register_t *retval)
{
struct sys_getitimer_args /* {
syscallarg(int) which;
syscallarg(struct itimerval *) itv;
} */ *uap = v;
struct proc *p = l->l_proc;
struct itimerval aitv;
int s, which;
which = SCARG(uap, which);
if ((u_int)which > ITIMER_PROF)
return (EINVAL);
if ((p->p_timers == NULL) || (p->p_timers->pts_timers[which] == NULL)){
timerclear(&aitv.it_value);
timerclear(&aitv.it_interval);
} else {
s = splclock();
timer_gettime(p->p_timers->pts_timers[which], &aitv);
splx(s);
}
return (copyout(&aitv, SCARG(uap, itv), sizeof(struct itimerval)));
}
/* BSD routine to set/arm an interval timer. */
/* ARGSUSED */
int
sys_setitimer(struct lwp *l, void *v, register_t *retval)
{
struct sys_setitimer_args /* {
syscallarg(int) which;
syscallarg(const struct itimerval *) itv;
syscallarg(struct itimerval *) oitv;
} */ *uap = v;
struct proc *p = l->l_proc;
int which = SCARG(uap, which);
struct sys_getitimer_args getargs;
struct itimerval aitv;
const struct itimerval *itvp;
struct ptimer *pt;
int s, error;
if ((u_int)which > ITIMER_PROF)
return (EINVAL);
itvp = SCARG(uap, itv);
if (itvp &&
(error = copyin(itvp, &aitv, sizeof(struct itimerval)) != 0))
return (error);
if (SCARG(uap, oitv) != NULL) {
SCARG(&getargs, which) = which;
SCARG(&getargs, itv) = SCARG(uap, oitv);
if ((error = sys_getitimer(l, &getargs, retval)) != 0)
return (error);
}
if (itvp == 0)
return (0);
if (itimerfix(&aitv.it_value) || itimerfix(&aitv.it_interval))
return (EINVAL);
/*
* Don't bother allocating data structures if the process just
* wants to clear the timer.
*/
if (!timerisset(&aitv.it_value) &&
((p->p_timers == NULL) ||(p->p_timers->pts_timers[which] == NULL)))
return (0);
if (p->p_timers == NULL)
timers_alloc(p);
if (p->p_timers->pts_timers[which] == NULL) {
pt = pool_get(&ptimer_pool, PR_WAITOK);
pt->pt_ev.sigev_notify = SIGEV_SIGNAL;
pt->pt_ev.sigev_value.sival_int = which;
pt->pt_overruns = 0;
pt->pt_proc = p;
pt->pt_type = which;
pt->pt_entry = which;
switch (which) {
case ITIMER_REAL:
callout_init(&pt->pt_ch);
pt->pt_ev.sigev_signo = SIGALRM;
break;
case ITIMER_VIRTUAL:
pt->pt_active = 0;
pt->pt_ev.sigev_signo = SIGVTALRM;
break;
case ITIMER_PROF:
pt->pt_active = 0;
pt->pt_ev.sigev_signo = SIGPROF;
break;
}
} else
pt = p->p_timers->pts_timers[which];
pt->pt_time = aitv;
p->p_timers->pts_timers[which] = pt;
s = splclock();
if ((which == ITIMER_REAL) && timerisset(&pt->pt_time.it_value)) {
/* Convert to absolute time */
timeradd(&pt->pt_time.it_value, &time, &pt->pt_time.it_value);
}
timer_settime(pt);
splx(s);
return (0);
}
/* Utility routines to manage the array of pointers to timers. */
void
timers_alloc(struct proc *p)
{
int i;
struct ptimers *pts;
pts = malloc(sizeof (struct ptimers), M_SUBPROC, 0);
LIST_INIT(&pts->pts_virtual);
LIST_INIT(&pts->pts_prof);
for (i = 0; i < TIMER_MAX; i++)
pts->pts_timers[i] = NULL;
pts->pts_fired = 0;
p->p_timers = pts;
}
/*
* Clean up the per-process timers. If "which" is set to TIMERS_ALL,
* then clean up all timers and free all the data structures. If
* "which" is set to TIMERS_POSIX, only clean up the timers allocated
* by timer_create(), not the BSD setitimer() timers, and only free the
* structure if none of those remain.
*/
void
timers_free(struct proc *p, int which)
{
int i, s;
struct ptimers *pts;
struct ptimer *pt, *ptn;
struct timeval tv;
if (p->p_timers) {
pts = p->p_timers;
if (which == TIMERS_ALL)
i = 0;
else {
s = splclock();
timerclear(&tv);
for (ptn = LIST_FIRST(&p->p_timers->pts_virtual);
ptn && ptn != pts->pts_timers[ITIMER_VIRTUAL];
ptn = LIST_NEXT(ptn, pt_list))
timeradd(&tv, &ptn->pt_time.it_value, &tv);
LIST_FIRST(&p->p_timers->pts_virtual) = NULL;
if (ptn) {
timeradd(&tv, &ptn->pt_time.it_value,
&ptn->pt_time.it_value);
LIST_INSERT_HEAD(&p->p_timers->pts_virtual,
ptn, pt_list);
}
timerclear(&tv);
for (ptn = LIST_FIRST(&p->p_timers->pts_prof);
ptn && ptn != pts->pts_timers[ITIMER_PROF];
ptn = LIST_NEXT(ptn, pt_list))
timeradd(&tv, &ptn->pt_time.it_value, &tv);
LIST_FIRST(&p->p_timers->pts_prof) = NULL;
if (ptn) {
timeradd(&tv, &ptn->pt_time.it_value,
&ptn->pt_time.it_value);
LIST_INSERT_HEAD(&p->p_timers->pts_prof, ptn,
pt_list);
}
splx(s);
i = 3;
}
for ( ; i < TIMER_MAX; i++)
if ((pt = pts->pts_timers[i]) != NULL) {
if (pt->pt_type == CLOCK_REALTIME)
callout_stop(&pt->pt_ch);
pts->pts_timers[i] = NULL;
pool_put(&ptimer_pool, pt);
}
if ((pts->pts_timers[0] == NULL) &&
(pts->pts_timers[1] == NULL) &&
(pts->pts_timers[2] == NULL)) {
p->p_timers = NULL;
free(pts, M_SUBPROC);
}
}
}
/*
* Check that a proposed value to load into the .it_value or
* .it_interval part of an interval timer is acceptable, and
* fix it to have at least minimal value (i.e. if it is less
* than the resolution of the clock, round it up.)
*/
int
itimerfix(struct timeval *tv)
{
if (tv->tv_sec < 0 || tv->tv_usec < 0 || tv->tv_usec >= 1000000)
return (EINVAL);
if (tv->tv_sec == 0 && tv->tv_usec != 0 && tv->tv_usec < tick)
tv->tv_usec = tick;
return (0);
}
/*
* Decrement an interval timer by a specified number
* of microseconds, which must be less than a second,
* i.e. < 1000000. If the timer expires, then reload
* it. In this case, carry over (usec - old value) to
* reduce the value reloaded into the timer so that
* the timer does not drift. This routine assumes
* that it is called in a context where the timers
* on which it is operating cannot change in value.
*/
int
itimerdecr(struct ptimer *pt, int usec)
{
struct itimerval *itp;
itp = &pt->pt_time;
if (itp->it_value.tv_usec < usec) {
if (itp->it_value.tv_sec == 0) {
/* expired, and already in next interval */
usec -= itp->it_value.tv_usec;
goto expire;
}
itp->it_value.tv_usec += 1000000;
itp->it_value.tv_sec--;
}
itp->it_value.tv_usec -= usec;
usec = 0;
if (timerisset(&itp->it_value))
return (1);
/* expired, exactly at end of interval */
expire:
if (timerisset(&itp->it_interval)) {
itp->it_value = itp->it_interval;
itp->it_value.tv_usec -= usec;
if (itp->it_value.tv_usec < 0) {
itp->it_value.tv_usec += 1000000;
itp->it_value.tv_sec--;
}
timer_settime(pt);
} else
itp->it_value.tv_usec = 0; /* sec is already 0 */
return (0);
}
void
itimerfire(struct ptimer *pt)
{
struct proc *p = pt->pt_proc;
int s;
if (pt->pt_ev.sigev_notify == SIGEV_SIGNAL) {
/*
* No RT signal infrastructure exists at this time;
* just post the signal number and throw away the
* value.
*/
if (sigismember(&p->p_sigctx.ps_siglist, pt->pt_ev.sigev_signo))
pt->pt_overruns++;
else {
ksiginfo_t ksi;
(void)memset(&ksi, 0, sizeof(ksi));
ksi.ksi_signo = pt->pt_ev.sigev_signo;
ksi.ksi_code = SI_TIMER;
ksi.ksi_sigval = pt->pt_ev.sigev_value;
pt->pt_poverruns = pt->pt_overruns;
pt->pt_overruns = 0;
kpsignal(p, &ksi, NULL);
}
} else if (pt->pt_ev.sigev_notify == SIGEV_SA && (p->p_flag & P_SA)) {
/* Cause the process to generate an upcall when it returns. */
struct sadata *sa = p->p_sa;
unsigned int i;
if (p->p_userret == NULL) {
/*
* XXX stop signals can be processed inside tsleep,
* which can be inside sa_yield's inner loop, which
* makes testing for sa_idle alone insuffucent to
* determine if we really should call setrunnable.
*/
pt->pt_poverruns = pt->pt_overruns;
pt->pt_overruns = 0;
i = 1 << pt->pt_entry;
p->p_timers->pts_fired = i;
p->p_userret = timerupcall;
p->p_userret_arg = p->p_timers;
SCHED_LOCK(s);
if (sa->sa_vp->l_flag & L_SA_IDLE) {
sa->sa_vp->l_flag &= ~L_SA_IDLE;
sched_wakeup(sa->sa_vp);
}
SCHED_UNLOCK(s);
} else if (p->p_userret == timerupcall) {
i = 1 << pt->pt_entry;
if ((p->p_timers->pts_fired & i) == 0) {
pt->pt_poverruns = pt->pt_overruns;
pt->pt_overruns = 0;
p->p_timers->pts_fired |= i;
} else
pt->pt_overruns++;
} else {
pt->pt_overruns++;
if ((p->p_flag & P_WEXIT) == 0)
printf("itimerfire(%d): overrun %d on timer %x (userret is %p)\n",
p->p_pid, pt->pt_overruns,
pt->pt_ev.sigev_value.sival_int,
p->p_userret);
}
}
}
/*
* ratecheck(): simple time-based rate-limit checking. see ratecheck(9)
* for usage and rationale.
*/
int
ratecheck(struct timeval *lasttime, const struct timeval *mininterval)
{
struct timeval tv, delta;
int s, rv = 0;
s = splclock();
tv = mono_time;
splx(s);
timersub(&tv, lasttime, &delta);
/*
* check for 0,0 is so that the message will be seen at least once,
* even if interval is huge.
*/
if (timercmp(&delta, mininterval, >=) ||
(lasttime->tv_sec == 0 && lasttime->tv_usec == 0)) {
*lasttime = tv;
rv = 1;
}
return (rv);
}
/*
* ppsratecheck(): packets (or events) per second limitation.
*/
int
ppsratecheck(struct timeval *lasttime, int *curpps, int maxpps)
{
struct timeval tv, delta;
int s, rv;
s = splclock();
tv = mono_time;
splx(s);
timersub(&tv, lasttime, &delta);
/*
* check for 0,0 is so that the message will be seen at least once.
* if more than one second have passed since the last update of
* lasttime, reset the counter.
*
* we do increment *curpps even in *curpps < maxpps case, as some may
* try to use *curpps for stat purposes as well.
*/
if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) ||
delta.tv_sec >= 1) {
*lasttime = tv;
*curpps = 0;
}
if (maxpps < 0)
rv = 1;
else if (*curpps < maxpps)
rv = 1;
else
rv = 0;
#if 1 /*DIAGNOSTIC?*/
/* be careful about wrap-around */
if (*curpps + 1 > *curpps)
*curpps = *curpps + 1;
#else
/*
* assume that there's not too many calls to this function.
* not sure if the assumption holds, as it depends on *caller's*
* behavior, not the behavior of this function.
* IMHO it is wrong to make assumption on the caller's behavior,
* so the above #if is #if 1, not #ifdef DIAGNOSTIC.
*/
*curpps = *curpps + 1;
#endif
return (rv);
}
Reference in New Issue View Git Blame Copy Permalink