1991/1004/gnot/mmu.c (diff list | history)

gnot/mmu.c on 1990/03091
1990/03091		#include "u.h" #include "lib.h" #include "mem.h" #include "dat.h" #include "fns.h"
1990/06021		struct { Lock; int init; KMap *free;
1991/0821		KMap arena[MB4/BY2PG]; /* kernel mmu maps up to 4MB */
1990/06021		}kmapalloc;
1990/03091		/* * Called splhi, not in Running state */ void mapstack(Proc *p) { ulong tlbvirt, tlbphys;
1990/1004		ulong next; MMU *mm, *mn, *me;
1990/03091
1991/0705
1991/0928		if(p->upage->va != (USERADDR|(p->pid&0xFFFF)) && p->pid != 0)
1990/03091		panic("mapstack %d 0x%lux 0x%lux", p->pid, p->upage->pa, p->upage->va); tlbvirt = USERADDR; tlbphys = PPN(p->upage->pa) | PTEVALID | PTEKERNEL; putkmmu(tlbvirt, tlbphys);
1990/1211		u = (User*)USERADDR;
1990/1004
1991/0705		if(p->newtlb) { flushmmu(); clearmmucache(); p->newtlb = 0; }
1990/1004		/* * if not a kernel process and this process was not the * last process on this machine, flush & preload mmu */ if(!p->kp && p!=m->lproc){ flushmmu(); /* * preload the MMU with the last (up to) NMMU user entries * previously faulted into it for this process. */ mn = &u->mc.mmu[u->mc.next&(NMMU-1)]; me = &u->mc.mmu[NMMU]; if(u->mc.next >= NMMU){ for(mm = mn; mm < me; mm++) UMAP[mm->va] = mm->pa; } for(mm = u->mc.mmu; mm < mn; mm++) UMAP[mm->va] = mm->pa; m->lproc = p; }
1990/03091		} void
1991/0507		mmurelease(Proc *p) { USED(p); } void
1990/03091		putkmmu(ulong tlbvirt, ulong tlbphys) { if(!(tlbvirt&KZERO)) panic("putkmmu"); tlbvirt &= ~KZERO; KMAP[(tlbvirt&0x003FE000L)>>2] = tlbphys; } void
1991/0705		putmmu(ulong tlbvirt, ulong tlbphys, Page *p)
1990/03091		{ if(tlbvirt&KZERO) panic("putmmu"); tlbphys |= VTAG(tlbvirt)<<24;
1990/1004		tlbvirt = (tlbvirt&0x003FE000L)>>2; if(u){ MMU *mp; int s; s = splhi(); mp = &(u->mc.mmu[u->mc.next&(NMMU-1)]); mp->pa = tlbphys; mp->va = tlbvirt; u->mc.next++; splx(s); } UMAP[tlbvirt] = tlbphys;
1990/03091		} void flushmmu(void) { flushcpucache(); *PARAM &= ~TLBFLUSH_; *PARAM |= TLBFLUSH_;
1990/1004		} void clearmmucache(void) { if(u == 0)
1991/0705		panic("clearmmucache");
1990/1004		u->mc.next = 0;
1990/06021		} void kmapinit(void) { KMap *k; int i, e; if(kmapalloc.init == 0){ k = &kmapalloc.arena[0];
1991/0821		k->va = KZERO|(MB4-256*1024-BY2PG);
1990/06021		k->next = 0; kmapalloc.free = k; kmapalloc.init = 1; return; }
1991/0821		e = (MB4 - 256*1024)/BY2PG; /* screen lives at top 256K */
1991/0802		i = PGROUND(((ulong)ialloc(0, 0))&~KZERO)/BY2PG;
1991/0821
1990/0709		print("%lud free map registers\n", e-i);
1991/0821
1990/06021		kmapalloc.free = 0; for(k=&kmapalloc.arena[i]; i<e; i++,k++){ k->va = i*BY2PG|KZERO; kunmap(k); } } KMap* kmap(Page *pg) { KMap *k;
1991/1004		int s; s = splhi();
1990/06021		lock(&kmapalloc); k = kmapalloc.free;
1990/0709		if(k == 0){ dumpstack();
1990/06021		panic("kmap");
1990/0709		}
1990/06021		kmapalloc.free = k->next; unlock(&kmapalloc);
1991/1004		splx(s);
1991/0821
1990/06021		k->pa = pg->pa; putkmmu(k->va, PPN(k->pa) | PTEVALID | PTEKERNEL);
1991/0828
1990/06021		return k; } void kunmap(KMap *k) {
1991/0827		int s;
1990/06021		k->pa = 0;
1991/0821		putkmmu(k->va, INVALIDPTE);
1991/0827		s = splhi();
1990/06021		lock(&kmapalloc); k->next = kmapalloc.free; kmapalloc.free = k; unlock(&kmapalloc);
1991/0827		splx(s);
1990/1211		} void invalidateu(void) { putkmmu(USERADDR, INVALIDPTE);
1990/03091		}