int
sys_swapcontext(struct thread *td, struct swapcontext_args *uap)
{
ucontext_t uc;
int ret;
if (uap->oucp == NULL || uap->ucp == NULL)
ret = EINVAL;
else {
bzero(&uc, sizeof(ucontext_t));
get_mcontext(td, &uc.uc_mcontext, GET_MC_CLEAR_RET);
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) {
kern_sigprocmask(td, SIG_SETMASK,
&uc.uc_sigmask, NULL, 0);
}
}
}
}
return (ret == 0 ? EJUSTRETURN : ret);
}
int
sys_sigreturn(struct thread *td, struct sigreturn_args *uap)
{
uint64_t sstatus;
ucontext_t uc;
int error;
if (uap == NULL)
return (EFAULT);
if (copyin(uap->sigcntxp, &uc, sizeof(uc)))
return (EFAULT);
/*
* Make sure the processor mode has not been tampered with and
* interrupts have not been disabled.
*/
sstatus = uc.uc_mcontext.mc_gpregs.gp_sstatus;
if ((sstatus & SSTATUS_PS) != 0 ||
(sstatus & SSTATUS_PIE) == 0)
return (EINVAL);
error = set_mcontext(td, &uc.uc_mcontext);
if (error != 0)
return (error);
set_fpcontext(td, &uc.uc_mcontext);
/* Restore signal mask. */
kern_sigprocmask(td, SIG_SETMASK, &uc.uc_sigmask, NULL, 0);
return (EJUSTRETURN);
}
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, GET_MC_CLEAR_RET);
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);
}
/*
* Switch to the target context. The current signal mask is saved in ucp
* and all signals are blocked. The call to set_mcontext() causes the
* specified context to be switched to (usually resuming as a return from
* the get_mcontext() procedure). The current context is thrown away.
*
* The target context being resumed is responsible for restoring the
* signal mask appropriate for the target context.
*/
int
_setcontext(ucontext_t *ucp)
{
int ret;
ret = _sigprocmask(SIG_BLOCK, &sigset_block_all, &ucp->uc_sigmask);
if (ret == 0)
ret = set_mcontext(&ucp->uc_mcontext);
return(ret);
}
static int
thr_create_initthr(struct thread *td, void *thunk)
{
struct thr_create_initthr_args *args;
/* Copy out the child tid. */
args = thunk;
if (args->tid != NULL && suword_lwpid(args->tid, td->td_tid))
return (EFAULT);
return (set_mcontext(td, &args->ctx.uc_mcontext));
}
/*
* Save the calling context in (oucp) then switch to (ucp).
*
* Block all signals while switching contexts. get_mcontext() returns zero
* when retrieving a context.
*
* When some other thread calls set_mcontext() to resume our thread,
* the resume point causes get_mcontext() to return non-zero to us.
* Signals will be blocked and we must restore the signal mask before
* returning.
*/
int
_swapcontext(ucontext_t *oucp, const ucontext_t *ucp)
{
int ret;
ret = _sigprocmask(SIG_BLOCK, &sigset_block_all, &oucp->uc_sigmask);
if (ret == 0) {
if (get_mcontext(&oucp->uc_mcontext) == 0) {
ret = set_mcontext(&ucp->uc_mcontext);
} else {
ret = _sigprocmask(SIG_SETMASK, &oucp->uc_sigmask, NULL);
}
}
return(ret);
}
/*
* System call to cleanup state after a signal
* has been taken. Reset signal mask and
* stack state from context left by sendsig (above).
* Return to previous pc as specified by
* context left by sendsig.
*/
int
sys_sigreturn(struct thread *td, struct sigreturn_args *uap)
{
ucontext_t uc;
int error;
error = copyin(uap->sigcntxp, &uc, sizeof(uc));
if (error != 0)
return (error);
error = set_mcontext(td, &uc.uc_mcontext);
if (error != 0)
return (error);
kern_sigprocmask(td, SIG_SETMASK, &uc.uc_sigmask, NULL, 0);
return (EJUSTRETURN);
}
int
sys_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) {
kern_sigprocmask(td, SIG_SETMASK, &uc.uc_sigmask,
NULL, 0);
}
}
}
return (ret == 0 ? EJUSTRETURN : ret);
}
static int
set_mcontext32(struct thread *td, mcontext32_t *mcp)
{
mcontext_t mcp64;
unsigned i;
mcp64.mc_onstack = mcp->mc_onstack;
mcp64.mc_pc = mcp->mc_pc;
for (i = 0; i < 32; i++)
mcp64.mc_regs[i] = mcp->mc_regs[i];
mcp64.sr = mcp->sr;
mcp64.mullo = mcp->mullo;
mcp64.mulhi = mcp->mulhi;
mcp64.mc_fpused = mcp->mc_fpused;
for (i = 0; i < 33; i++)
mcp64.mc_fpregs[i] = mcp->mc_fpregs[i];
mcp64.mc_fpc_eir = mcp->mc_fpc_eir;
mcp64.mc_tls = (void *)(intptr_t)mcp->mc_tls;
return (set_mcontext(td, &mcp64));
}
int
sys_sigreturn(struct thread *td, struct sigreturn_args *uap)
{
ucontext_t uc;
uint32_t spsr;
if (uap == NULL)
return (EFAULT);
if (copyin(uap->sigcntxp, &uc, sizeof(uc)))
return (EFAULT);
spsr = uc.uc_mcontext.mc_gpregs.gp_spsr;
if ((spsr & PSR_M_MASK) != PSR_M_EL0t ||
(spsr & (PSR_F | PSR_I | PSR_A | PSR_D)) != 0)
return (EINVAL);
set_mcontext(td, &uc.uc_mcontext);
set_fpcontext(td, &uc.uc_mcontext);
/* Restore signal mask. */
kern_sigprocmask(td, SIG_SETMASK, &uc.uc_sigmask, NULL, 0);
return (EJUSTRETURN);
}
static int
create_thread(struct thread *td, mcontext_t *ctx,
void (*start_func)(void *), void *arg,
char *stack_base, size_t stack_size,
char *tls_base,
long *child_tid, long *parent_tid,
int flags, struct rtprio *rtp)
{
stack_t stack;
struct thread *newtd;
struct proc *p;
int error;
p = td->td_proc;
/* Have race condition but it is cheap. */
if (p->p_numthreads >= max_threads_per_proc) {
++max_threads_hits;
return (EPROCLIM);
}
if (rtp != NULL) {
switch(rtp->type) {
case RTP_PRIO_REALTIME:
case RTP_PRIO_FIFO:
/* Only root can set scheduler policy */
if (priv_check(td, PRIV_SCHED_SETPOLICY) != 0)
return (EPERM);
if (rtp->prio > RTP_PRIO_MAX)
return (EINVAL);
break;
case RTP_PRIO_NORMAL:
rtp->prio = 0;
break;
default:
return (EINVAL);
}
}
#ifdef RACCT
PROC_LOCK(td->td_proc);
error = racct_add(p, RACCT_NTHR, 1);
PROC_UNLOCK(td->td_proc);
if (error != 0)
return (EPROCLIM);
#endif
/* Initialize our td */
newtd = thread_alloc(0);
if (newtd == NULL) {
error = ENOMEM;
goto fail;
}
cpu_set_upcall(newtd, td);
/*
* Try the copyout as soon as we allocate the td so we don't
* have to tear things down in a failure case below.
* Here we copy out tid to two places, one for child and one
* for parent, because pthread can create a detached thread,
* if parent wants to safely access child tid, it has to provide
* its storage, because child thread may exit quickly and
* memory is freed before parent thread can access it.
*/
if ((child_tid != NULL &&
suword_lwpid(child_tid, newtd->td_tid)) ||
(parent_tid != NULL &&
suword_lwpid(parent_tid, newtd->td_tid))) {
thread_free(newtd);
error = EFAULT;
goto fail;
}
bzero(&newtd->td_startzero,
__rangeof(struct thread, td_startzero, td_endzero));
bcopy(&td->td_startcopy, &newtd->td_startcopy,
__rangeof(struct thread, td_startcopy, td_endcopy));
newtd->td_proc = td->td_proc;
newtd->td_ucred = crhold(td->td_ucred);
if (ctx != NULL) { /* old way to set user context */
error = set_mcontext(newtd, ctx);
if (error != 0) {
thread_free(newtd);
crfree(td->td_ucred);
goto fail;
}
} else {
/* Set up our machine context. */
stack.ss_sp = stack_base;
stack.ss_size = stack_size;
/* Set upcall address to user thread entry function. */
cpu_set_upcall_kse(newtd, start_func, arg, &stack);
/* Setup user TLS address and TLS pointer register. */
error = cpu_set_user_tls(newtd, tls_base);
if (error != 0) {
thread_free(newtd);
crfree(td->td_ucred);
goto fail;
}
}
PROC_LOCK(td->td_proc);
td->td_proc->p_flag |= P_HADTHREADS;
thread_link(newtd, p);
bcopy(p->p_comm, newtd->td_name, sizeof(newtd->td_name));
thread_lock(td);
/* let the scheduler know about these things. */
sched_fork_thread(td, newtd);
thread_unlock(td);
if (P_SHOULDSTOP(p))
newtd->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
PROC_UNLOCK(p);
tidhash_add(newtd);
thread_lock(newtd);
if (rtp != NULL) {
if (!(td->td_pri_class == PRI_TIMESHARE &&
rtp->type == RTP_PRIO_NORMAL)) {
rtp_to_pri(rtp, newtd);
sched_prio(newtd, newtd->td_user_pri);
} /* ignore timesharing class */
}
TD_SET_CAN_RUN(newtd);
sched_add(newtd, SRQ_BORING);
thread_unlock(newtd);
return (0);
fail:
#ifdef RACCT
PROC_LOCK(p);
racct_sub(p, RACCT_NTHR, 1);
PROC_UNLOCK(p);
#endif
return (error);
}