1328e1c4be
syscall return values should be cleared. The system calls getcontext() and swapcontext() want to return 0 on success but these contexts can be switched to at a later time so the return values need to be cleared in the saved register sets. Other callers of get_mcontext() would normally want the context without clearing the return values. Remove the i386-specific context saving from the KSE code. get_mcontext() is not i386-specific any more. Fix a bad pointer in the alpha get_mcontext() code. The context was being bcopy()'d from &td->tf_frame, but tf_frame is itself a pointer, so the thread was being copied instead. Spotted by jake. Glanced at by: jake Reviewed by: bde (months ago)
138 lines
3.5 KiB
C
138 lines
3.5 KiB
C
/*-
|
|
* Copyright (c) 2002 Daniel M. Eischen <deischen@freebsd.org>
|
|
* 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
|
|
*
|
|
*/
|
|
/*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/sysent.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/sysproto.h>
|
|
#include <sys/signalvar.h>
|
|
#include <sys/ucontext.h>
|
|
|
|
/*
|
|
* The first two fields of a ucontext_t are the signal mask and
|
|
* the machine context. The next field is uc_link; we want to
|
|
* avoid destroying the link when copying out contexts.
|
|
*/
|
|
#define UC_COPY_SIZE offsetof(ucontext_t, uc_link)
|
|
|
|
#ifndef _SYS_SYSPROTO_H_
|
|
struct getcontext_args {
|
|
struct __ucontext *ucp;
|
|
}
|
|
struct setcontext_args {
|
|
const struct __ucontext_t *ucp;
|
|
}
|
|
struct swapcontext_args {
|
|
struct __ucontext *oucp;
|
|
const struct __ucontext_t *ucp;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
getcontext(struct thread *td, struct getcontext_args *uap)
|
|
{
|
|
ucontext_t uc;
|
|
int ret;
|
|
|
|
if (uap->ucp == NULL)
|
|
ret = EINVAL;
|
|
else {
|
|
get_mcontext(td, &uc.uc_mcontext, 1);
|
|
PROC_LOCK(td->td_proc);
|
|
uc.uc_sigmask = td->td_sigmask;
|
|
PROC_UNLOCK(td->td_proc);
|
|
ret = copyout(&uc, uap->ucp, UC_COPY_SIZE);
|
|
}
|
|
return (ret);
|
|
}
|
|
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
setcontext(struct thread *td, struct setcontext_args *uap)
|
|
{
|
|
ucontext_t uc;
|
|
int ret;
|
|
|
|
if (uap->ucp == NULL)
|
|
ret = EINVAL;
|
|
else {
|
|
ret = copyin(uap->ucp, &uc, UC_COPY_SIZE);
|
|
if (ret == 0) {
|
|
ret = set_mcontext(td, &uc.uc_mcontext);
|
|
if (ret == 0) {
|
|
SIG_CANTMASK(uc.uc_sigmask);
|
|
PROC_LOCK(td->td_proc);
|
|
td->td_sigmask = uc.uc_sigmask;
|
|
PROC_UNLOCK(td->td_proc);
|
|
}
|
|
}
|
|
}
|
|
return (ret == 0 ? EJUSTRETURN : ret);
|
|
}
|
|
|
|
int
|
|
swapcontext(struct thread *td, struct swapcontext_args *uap)
|
|
{
|
|
ucontext_t uc;
|
|
int ret;
|
|
|
|
if (uap->oucp == NULL || uap->ucp == NULL)
|
|
ret = EINVAL;
|
|
else {
|
|
get_mcontext(td, &uc.uc_mcontext, 1);
|
|
PROC_LOCK(td->td_proc);
|
|
uc.uc_sigmask = td->td_sigmask;
|
|
PROC_UNLOCK(td->td_proc);
|
|
ret = copyout(&uc, uap->oucp, UC_COPY_SIZE);
|
|
if (ret == 0) {
|
|
ret = copyin(uap->ucp, &uc, UC_COPY_SIZE);
|
|
if (ret == 0) {
|
|
ret = set_mcontext(td, &uc.uc_mcontext);
|
|
if (ret == 0) {
|
|
SIG_CANTMASK(uc.uc_sigmask);
|
|
PROC_LOCK(td->td_proc);
|
|
td->td_sigmask = uc.uc_sigmask;
|
|
PROC_UNLOCK(td->td_proc);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return (ret == 0 ? EJUSTRETURN : ret);
|
|
}
|