uintptr
sysrfork(va_list list)
{
Proc *p;
int n, i;
Fgrp *ofg;
Pgrp *opg;
Rgrp *org;
Egrp *oeg;
ulong pid, flag;
Mach *wm;
flag = va_arg(list, ulong);
/* Check flags before we commit */
if((flag & (RFFDG|RFCFDG)) == (RFFDG|RFCFDG))
error(Ebadarg);
if((flag & (RFNAMEG|RFCNAMEG)) == (RFNAMEG|RFCNAMEG))
error(Ebadarg);
if((flag & (RFENVG|RFCENVG)) == (RFENVG|RFCENVG))
error(Ebadarg);
if((flag&RFPROC) == 0) {
if(flag & (RFMEM|RFNOWAIT))
error(Ebadarg);
if(flag & (RFFDG|RFCFDG)) {
ofg = up->fgrp;
if(flag & RFFDG)
up->fgrp = dupfgrp(ofg);
else
up->fgrp = dupfgrp(nil);
closefgrp(ofg);
}
if(flag & (RFNAMEG|RFCNAMEG)) {
opg = up->pgrp;
up->pgrp = newpgrp();
if(flag & RFNAMEG)
pgrpcpy(up->pgrp, opg);
/* inherit noattach */
up->pgrp->noattach = opg->noattach;
closepgrp(opg);
}
if(flag & RFNOMNT)
up->pgrp->noattach = 1;
if(flag & RFREND) {
org = up->rgrp;
up->rgrp = newrgrp();
closergrp(org);
}
if(flag & (RFENVG|RFCENVG)) {
oeg = up->egrp;
up->egrp = smalloc(sizeof(Egrp));
up->egrp->ref = 1;
if(flag & RFENVG)
envcpy(up->egrp, oeg);
closeegrp(oeg);
}
if(flag & RFNOTEG)
up->noteid = pidalloc(0);
return 0;
}
p = newproc();
p->scallnr = up->scallnr;
p->s = up->s;
p->nerrlab = 0;
p->slash = up->slash;
p->dot = up->dot;
incref(p->dot);
memmove(p->note, up->note, sizeof(p->note));
p->privatemem = up->privatemem;
p->noswap = up->noswap;
p->nnote = up->nnote;
p->notified = 0;
p->lastnote = up->lastnote;
p->notify = up->notify;
p->ureg = up->ureg;
p->dbgreg = 0;
/* Abort the child process on error */
if(waserror()){
p->kp = 1;
kprocchild(p, abortion, 0);
ready(p);
nexterror();
}
/* Make a new set of memory segments */
n = flag & RFMEM;
qlock(&p->seglock);
if(waserror()){
qunlock(&p->seglock);
nexterror();
}
for(i = 0; i < NSEG; i++)
if(up->seg[i] != nil)
p->seg[i] = dupseg(up->seg, i, n);
qunlock(&p->seglock);
poperror();
/* File descriptors */
if(flag & (RFFDG|RFCFDG)) {
if(flag & RFFDG)
p->fgrp = dupfgrp(up->fgrp);
else
p->fgrp = dupfgrp(nil);
}
else {
p->fgrp = up->fgrp;
incref(p->fgrp);
}
/* Process groups */
if(flag & (RFNAMEG|RFCNAMEG)) {
p->pgrp = newpgrp();
if(flag & RFNAMEG)
pgrpcpy(p->pgrp, up->pgrp);
/* inherit noattach */
p->pgrp->noattach = up->pgrp->noattach;
}
else {
p->pgrp = up->pgrp;
incref(p->pgrp);
}
if(flag & RFNOMNT)
p->pgrp->noattach = 1;
if(flag & RFREND)
p->rgrp = newrgrp();
else {
incref(up->rgrp);
p->rgrp = up->rgrp;
}
/* Environment group */
if(flag & (RFENVG|RFCENVG)) {
p->egrp = smalloc(sizeof(Egrp));
p->egrp->ref = 1;
if(flag & RFENVG)
envcpy(p->egrp, up->egrp);
}
else {
p->egrp = up->egrp;
incref(p->egrp);
}
p->hang = up->hang;
p->procmode = up->procmode;
if(up->procctl == Proc_tracesyscall)
p->procctl = Proc_tracesyscall;
poperror(); /* abortion */
/* Craft a return frame which will cause the child to pop out of
* the scheduler in user mode with the return register zero
*/
forkchild(p, up->dbgreg);
p->parent = up;
if((flag&RFNOWAIT) == 0){
p->parentpid = up->pid;
lock(&up->exl);
up->nchild++;
unlock(&up->exl);
}
if((flag&RFNOTEG) == 0)
p->noteid = up->noteid;
pid = p->pid;
memset(p->time, 0, sizeof(p->time));
p->time[TReal] = MACHP(0)->ticks;
kstrdup(&p->text, up->text);
kstrdup(&p->user, up->user);
procfork(p);
/*
* since the bss/data segments are now shareable,
* any mmu info about this process is now stale
* (i.e. has bad properties) and has to be discarded.
*/
flushmmu();
p->basepri = up->basepri;
p->priority = up->basepri;
p->fixedpri = up->fixedpri;
p->mp = up->mp;
wm = up->wired;
if(wm)
procwired(p, wm->machno);
ready(p);
sched();
return pid;
}
void
userinit(void)
{
Proc *p;
Segment *s;
KMap *k;
Page *pg;
p = newproc();
p->pgrp = newpgrp();
p->egrp = smalloc(sizeof(Egrp));
p->egrp->ref = 1;
p->fgrp = dupfgrp(nil);
p->rgrp = newrgrp();
p->procmode = 0640;
kstrdup(&eve, "");
kstrdup(&p->text, "*init*");
kstrdup(&p->user, eve);
/*
* Kernel Stack
*
* N.B. make sure there's enough space for syscall to check
* for valid args and
* space for gotolabel's return PC
* AMD64 stack must be quad-aligned.
*/
p->sched.pc = PTR2UINT(init0);
p->sched.sp = PTR2UINT(p->kstack+KSTACK-sizeof(up->arg)-sizeof(uintptr));
p->sched.sp = STACKALIGN(p->sched.sp);
/*
* User Stack
*
* Technically, newpage can't be called here because it
* should only be called when in a user context as it may
* try to sleep if there are no pages available, but that
* shouldn't be the case here.
*/
s = newseg(SG_STACK, USTKTOP-USTKSIZE, USTKSIZE/BIGPGSZ);
p->seg[SSEG] = s;
pg = newpage(1, 0, USTKTOP-BIGPGSZ, BIGPGSZ, -1);
segpage(s, pg);
k = kmap(pg);
bootargs(VA(k));
kunmap(k);
/*
* Text
*/
s = newseg(SG_TEXT, UTZERO, 1);
s->flushme++;
p->seg[TSEG] = s;
pg = newpage(1, 0, UTZERO, BIGPGSZ, -1);
memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
segpage(s, pg);
k = kmap(s->map[0]->pages[0]);
memmove(UINT2PTR(VA(k)), initcode, sizeof initcode);
kunmap(k);
ready(p);
}
