ref: 215b67ff3d630c56418026dda7ae68f23111c4a5
dir: /sys/src/9/pc64/main.c/
#include "u.h" #include "../port/lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "io.h" #include "tos.h" #include "ureg.h" #include "init.h" #include "pool.h" #include "reboot.h" Conf conf; int delaylink; int idle_spin; extern void (*i8237alloc)(void); extern void bootscreeninit(void); void confinit(void) { char *p; int i, userpcnt; ulong kpages; if(p = getconf("service")){ if(strcmp(p, "cpu") == 0) cpuserver = 1; else if(strcmp(p,"terminal") == 0) cpuserver = 0; } if(p = getconf("*kernelpercent")) userpcnt = 100 - strtol(p, 0, 0); else userpcnt = 0; conf.npage = 0; for(i=0; i<nelem(conf.mem); i++) conf.npage += conf.mem[i].npage; conf.nproc = 100 + ((conf.npage*BY2PG)/MB)*5; if(cpuserver) conf.nproc *= 3; if(conf.nproc > 2000) conf.nproc = 2000; conf.nimage = 200; conf.nswap = conf.nproc*80; conf.nswppo = 4096; if(cpuserver) { if(userpcnt < 10) userpcnt = 70; kpages = conf.npage - (conf.npage*userpcnt)/100; conf.nimage = conf.nproc; } else { if(userpcnt < 10) { if(conf.npage*BY2PG < 16*MB) userpcnt = 50; else userpcnt = 60; } kpages = conf.npage - (conf.npage*userpcnt)/100; /* * Make sure terminals with low memory get at least * 4MB on the first Image chunk allocation. */ if(conf.npage*BY2PG < 16*MB) imagmem->minarena = 4*MB; } /* * can't go past the end of virtual memory. */ if(kpages > ((uintptr)-KZERO)/BY2PG) kpages = ((uintptr)-KZERO)/BY2PG; conf.upages = conf.npage - kpages; conf.ialloc = (kpages/2)*BY2PG; /* * Guess how much is taken by the large permanent * datastructures. Mntcache and Mntrpc are not accounted for. */ kpages *= BY2PG; kpages -= conf.nproc*sizeof(Proc) + conf.nimage*sizeof(Image) + conf.nswap + conf.nswppo*sizeof(Page*); mainmem->maxsize = kpages; /* * the dynamic allocation will balance the load properly, * hopefully. be careful with 32-bit overflow. */ imagmem->maxsize = kpages - (kpages/10); if(p = getconf("*imagemaxmb")){ imagmem->maxsize = strtol(p, nil, 0)*MB; if(imagmem->maxsize > mainmem->maxsize) imagmem->maxsize = mainmem->maxsize; } } /* * The palloc.pages array can be a large chunk out of the 2GB * window above KZERO, so we allocate the array from * upages and map in the VMAP window before pageinit() */ static void preallocpages(void) { Pallocmem *pm; uintptr va, base, top; vlong size; ulong np; int i; np = 0; for(i=0; i<nelem(palloc.mem); i++){ pm = &palloc.mem[i]; np += pm->npage; } size = (uvlong)np * BY2PG; size += sizeof(Page) + BY2PG; /* round up */ size = (size / (sizeof(Page) + BY2PG)) * sizeof(Page); size = ROUND(size, PGLSZ(1)); for(i=0; i<nelem(palloc.mem); i++){ pm = &palloc.mem[i]; base = ROUND(pm->base, PGLSZ(1)); top = pm->base + (uvlong)pm->npage * BY2PG; if((base + size) <= VMAPSIZE && (vlong)(top - base) >= size){ va = base + VMAP; pmap(m->pml4, base | PTEGLOBAL|PTEWRITE|PTEVALID, va, size); palloc.pages = (Page*)va; pm->base = base + size; pm->npage = (top - pm->base)/BY2PG; break; } } } void machinit(void) { int machno; Segdesc *gdt; uintptr *pml4; machno = m->machno; pml4 = m->pml4; gdt = m->gdt; memset(m, 0, sizeof(Mach)); m->machno = machno; m->pml4 = pml4; m->gdt = gdt; m->perf.period = 1; /* * For polled uart output at boot, need * a default delay constant. 100000 should * be enough for a while. Cpuidentify will * calculate the real value later. */ m->loopconst = 100000; } void mach0init(void) { conf.nmach = 1; MACHP(0) = (Mach*)CPU0MACH; m->machno = 0; m->pml4 = (u64int*)CPU0PML4; m->gdt = (Segdesc*)CPU0GDT; machinit(); active.machs[0] = 1; active.exiting = 0; } void init0(void) { char buf[2*KNAMELEN], **sp; up->nerrlab = 0; spllo(); /* * These are o.k. because rootinit is null. * Then early kproc's will have a root and dot. */ up->slash = namec("#/", Atodir, 0, 0); pathclose(up->slash->path); up->slash->path = newpath("/"); up->dot = cclone(up->slash); chandevinit(); if(!waserror()){ snprint(buf, sizeof(buf), "%s %s", arch->id, conffile); ksetenv("terminal", buf, 0); ksetenv("cputype", "amd64", 0); if(cpuserver) ksetenv("service", "cpu", 0); else ksetenv("service", "terminal", 0); setconfenv(); poperror(); } kproc("alarm", alarmkproc, 0); sp = (char**)(USTKTOP - sizeof(Tos) - 8 - sizeof(sp[0])*4); sp[3] = sp[2] = nil; strcpy(sp[1] = (char*)&sp[4], "boot"); sp[0] = nil; touser(sp); } void userinit(void) { void *v; Proc *p; Segment *s; 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); procsetup(p); /* * Kernel Stack * * N.B. make sure there's enough space for syscall to check * for valid args and * 8 bytes for gotolabel's return PC */ p->sched.pc = (uintptr)init0; p->sched.sp = (uintptr)p->kstack+KSTACK-(sizeof(Sargs)+BY2WD); /* temporarily set up for kmap() */ up = p; /* * User Stack */ s = newseg(SG_STACK, USTKTOP-USTKSIZE, USTKSIZE/BY2PG); p->seg[SSEG] = s; pg = newpage(0, 0, USTKTOP-BY2PG); segpage(s, pg); v = kmap(pg); memset(v, 0, BY2PG); kunmap(v); /* * Text */ s = newseg(SG_TEXT, UTZERO, 1); s->flushme++; p->seg[TSEG] = s; pg = newpage(0, 0, UTZERO); pg->txtflush = ~0; segpage(s, pg); v = kmap(pg); memset(v, 0, BY2PG); memmove(v, initcode, sizeof initcode); kunmap(v); /* free kmap */ mmurelease(p); up = nil; ready(p); } void main() { mach0init(); bootargsinit(); ioinit(); i8250console(); quotefmtinstall(); screeninit(); print("\nPlan 9\n"); trapinit0(); i8253init(); cpuidentify(); meminit(); confinit(); xinit(); archinit(); bootscreeninit(); if(i8237alloc != nil) i8237alloc(); trapinit(); printinit(); cpuidprint(); mmuinit(); if(arch->intrinit) arch->intrinit(); timersinit(); mathinit(); if(arch->clockenable) arch->clockenable(); procinit0(); initseg(); if(delaylink){ bootlinks(); pcimatch(0, 0, 0); }else links(); chandevreset(); netconsole(); preallocpages(); pageinit(); swapinit(); userinit(); schedinit(); } void exit(int) { cpushutdown(); arch->reset(); } void reboot(void *entry, void *code, ulong size) { void (*f)(uintptr, uintptr, ulong); writeconf(); /* * the boot processor is cpu0. execute this function on it * so that the new kernel has the same cpu0. this only matters * because the hardware has a notion of which processor was the * boot processor and we look at it at start up. */ if (m->machno != 0) { procwired(up, 0); sched(); } cpushutdown(); splhi(); /* turn off buffered serial console */ serialoq = nil; /* shutdown devices */ chandevshutdown(); arch->introff(); /* * This allows the reboot code to turn off the page mapping */ *mmuwalk(m->pml4, 0, 3, 0) = *mmuwalk(m->pml4, KZERO, 3, 0); *mmuwalk(m->pml4, 0, 2, 0) = *mmuwalk(m->pml4, KZERO, 2, 0); mmuflushtlb(); /* setup reboot trampoline function */ f = (void*)REBOOTADDR; memmove(f, rebootcode, sizeof(rebootcode)); /* off we go - never to return */ coherence(); (*f)((uintptr)entry & ~0xF0000000UL, (uintptr)PADDR(code), size); } /* * SIMD Floating Point. * Assembler support to get at the individual instructions * is in l.s. * There are opportunities to be lazier about saving and * restoring the state and allocating the storage needed. */ extern void _clts(void); extern void _fldcw(u16int); extern void _fnclex(void); extern void _fninit(void); extern void _fxrstor(Fxsave*); extern void _fxsave(Fxsave*); extern void _fwait(void); extern void _ldmxcsr(u32int); extern void _stts(void); /* * not used, AMD64 mandated SSE */ void fpx87save(FPsave*) { } void fpx87restore(FPsave*) { } void fpssesave(FPsave *fps) { Fxsave *fx = (Fxsave*)ROUND(((uintptr)fps), FPalign); _fxsave(fx); _stts(); if(fx != (Fxsave*)fps) memmove((Fxsave*)fps, fx, sizeof(Fxsave)); } void fpsserestore(FPsave *fps) { Fxsave *fx = (Fxsave*)ROUND(((uintptr)fps), FPalign); if(fx != (Fxsave*)fps) memmove(fx, (Fxsave*)fps, sizeof(Fxsave)); _clts(); _fxrstor(fx); } static char* mathmsg[] = { nil, /* handled below */ "denormalized operand", "division by zero", "numeric overflow", "numeric underflow", "precision loss", }; static void mathnote(ulong status, uintptr pc) { char *msg, note[ERRMAX]; int i; /* * Some attention should probably be paid here to the * exception masks and error summary. */ msg = "unknown exception"; for(i = 1; i <= 5; i++){ if(!((1<<i) & status)) continue; msg = mathmsg[i]; break; } if(status & 0x01){ if(status & 0x40){ if(status & 0x200) msg = "stack overflow"; else msg = "stack underflow"; }else msg = "invalid operation"; } snprint(note, sizeof note, "sys: fp: %s fppc=%#p status=0x%lux", msg, pc, status); postnote(up, 1, note, NDebug); } /* * math coprocessor error */ static void matherror(Ureg*, void*) { /* * Save FPU state to check out the error. */ fpsave(&up->fpsave); up->fpstate = FPinactive; mathnote(up->fpsave.fsw, up->fpsave.rip); } /* * SIMD error */ static void simderror(Ureg *ureg, void*) { fpsave(&up->fpsave); up->fpstate = FPinactive; mathnote(up->fpsave.mxcsr & 0x3f, ureg->pc); } void fpinit(void) { /* * A process tries to use the FPU for the * first time and generates a 'device not available' * exception. * Turn the FPU on and initialise it for use. * Set the precision and mask the exceptions * we don't care about from the generic Mach value. */ _clts(); _fninit(); _fwait(); _fldcw(0x0232); _ldmxcsr(0x1900); } /* * math coprocessor emulation fault */ static void mathemu(Ureg *ureg, void*) { ulong status, control; if(up->fpstate & FPillegal){ /* someone did floating point in a note handler */ postnote(up, 1, "sys: floating point in note handler", NDebug); return; } switch(up->fpstate){ case FPinit: fpinit(); up->fpstate = FPactive; break; case FPinactive: /* * Before restoring the state, check for any pending * exceptions, there's no way to restore the state without * generating an unmasked exception. * More attention should probably be paid here to the * exception masks and error summary. */ status = up->fpsave.fsw; control = up->fpsave.fcw; if((status & ~control) & 0x07F){ mathnote(status, up->fpsave.rip); break; } fprestore(&up->fpsave); up->fpstate = FPactive; break; case FPactive: panic("math emu pid %ld %s pc %#p", up->pid, up->text, ureg->pc); break; } } /* * math coprocessor segment overrun */ static void mathover(Ureg*, void*) { pexit("math overrun", 0); } void mathinit(void) { trapenable(VectorCERR, matherror, 0, "matherror"); if(X86FAMILY(m->cpuidax) == 3) intrenable(IrqIRQ13, matherror, 0, BUSUNKNOWN, "matherror"); trapenable(VectorCNA, mathemu, 0, "mathemu"); trapenable(VectorCSO, mathover, 0, "mathover"); trapenable(VectorSIMD, simderror, 0, "simderror"); } void procsetup(Proc *p) { p->fpstate = FPinit; _stts(); cycles(&p->kentry); p->pcycles = -p->kentry; } void procfork(Proc *p) { int s; p->kentry = up->kentry; p->pcycles = -p->kentry; /* save floating point state */ s = splhi(); switch(up->fpstate & ~FPillegal){ case FPactive: fpsave(&up->fpsave); up->fpstate = FPinactive; case FPinactive: p->fpsave = up->fpsave; p->fpstate = FPinactive; } splx(s); } void procrestore(Proc *p) { uvlong t; if(p->dr[7] != 0){ m->dr7 = p->dr[7]; putdr(p->dr); } if(p->kp) return; cycles(&t); p->kentry += t; p->pcycles -= t; } void procsave(Proc *p) { uvlong t; if(m->dr7 != 0){ m->dr7 = 0; putdr7(0); } cycles(&t); p->kentry -= t; p->pcycles += t; if(p->fpstate == FPactive){ if(p->state == Moribund){ _clts(); _fnclex(); _stts(); } else{ /* * Fpsave() stores without handling pending * unmasked exeptions. Postnote() can't be called * here as sleep() already has up->rlock, so * the handling of pending exceptions is delayed * until the process runs again and generates an * emulation fault to activate the FPU. */ fpsave(&p->fpsave); } p->fpstate = FPinactive; } /* * While this processor is in the scheduler, the process could run * on another processor and exit, returning the page tables to * the free list where they could be reallocated and overwritten. * When this processor eventually has to get an entry from the * trashed page tables it will crash. * * If there's only one processor, this can't happen. * You might think it would be a win not to do this in that case, * especially on VMware, but it turns out not to matter. */ mmuflushtlb(); }