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1990/03091/gnot/mmu.c (diff list | history)

1990/03091/sys/src/9/gnot/mmu.c:1,481990/06021/sys/src/9/gnot/mmu.c:1,107 (short | long | prev | next)
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; 
	KMap	arena[4*1024*1024/BY2PG];	/* kernel mmu maps up to 4MB */ 
}kmapalloc; 
 
1990/03091    
/* 
 * Called splhi, not in Running state 
 */ 
void 
mapstack(Proc *p) 
{ 
	ulong tlbvirt, tlbphys; 
 
	if(p->upage->va != (USERADDR|(p->pid&0xFFFF))) 
		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); 
	flushmmu(); 
	u = (User*)USERADDR; 
} 
 
void 
putkmmu(ulong tlbvirt, ulong tlbphys) 
{ 
	if(!(tlbvirt&KZERO)) 
		panic("putkmmu"); 
	tlbvirt &= ~KZERO; 
	KMAP[(tlbvirt&0x003FE000L)>>2] = tlbphys; 
} 
 
void 
putmmu(ulong tlbvirt, ulong tlbphys) 
{ 
	if(tlbvirt&KZERO) 
		panic("putmmu"); 
	tlbphys |= VTAG(tlbvirt)<<24; 
	UMAP[(tlbvirt&0x003FE000L)>>2] = tlbphys; 
} 
 
void 
flushmmu(void) 
{ 
	flushcpucache(); 
	*PARAM &= ~TLBFLUSH_; 
	*PARAM |= TLBFLUSH_; 
1990/06021    
} 
 
void 
kmapinit(void) 
{ 
	KMap *k; 
	int i, e; 
 
	if(kmapalloc.init == 0){ 
		k = &kmapalloc.arena[0]; 
		k->va = KZERO|(3*1024*1024); 
		k->next = 0; 
		kmapalloc.free = k; 
		kmapalloc.init = 1; 
		return; 
	} 
	e = (4*1024*1024 - 256*1024)/BY2PG;	/* screen lives at top 256K */ 
	i = (((ulong)ialloc(0, 0))&~KZERO)/BY2PG; 
print("kmapinit %d", i); 
	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; 
 
	lock(&kmapalloc); 
	k = kmapalloc.free; 
	if(k == 0) 
		panic("kmap"); 
	kmapalloc.free = k->next; 
	unlock(&kmapalloc); 
	k->pa = pg->pa; 
	putkmmu(k->va, PPN(k->pa) | PTEVALID | PTEKERNEL); 
	return k; 
} 
 
void 
kunmap(KMap *k) 
{ 
	k->pa = 0; 
	lock(&kmapalloc); 
	k->next = kmapalloc.free; 
	kmapalloc.free = k; 
	putkmmu(k->va, INVALIDPTE); 
	unlock(&kmapalloc); 
1990/03091    
} 


source code copyright © 1990-2005 Lucent Technologies; see license
Plan 9 distribution
comments to russ cox (rsc@swtch.com)