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#include <u.h>
#include <libc.h>
#include <thread.h>
#include "dat.h"
#include "fns.h"
Segment *
newseg(u32int start, u32int size, int idx)
{
Segment *s;
s = emallocz(sizeof *s);
incref(s);
s->start = start;
s->size = size;
s->ref = emalloc(size + sizeof(Ref));
memset(s->ref, 0, sizeof(Ref));
incref(s->ref);
s->data = s->ref + 1;
if(idx == SEGBSS)
s->flags = SEGFLLOCK;
P->S[idx] = s;
return s;
}
void
freesegs(void)
{
Segment **s;
for(s = P->S; s < P->S + SEGNUM; s++) {
if(*s == nil)
continue;
if(decref((*s)->ref) == 0)
free((*s)->ref);
if(decref(*s) == 0)
free(*s);
*s = nil;
}
}
void *
vaddr(u32int addr, Segment **seg)
{
Segment **ss, *s;
for(ss = P->S; ss < P->S + SEGNUM; ss++) {
if(*ss == nil)
continue;
s = *ss;
if(addr >= s->start && addr < s->start + s->size) {
if(s->flags & SEGFLLOCK)
rlock(&s->rw);
*seg = s;
return (char *)s->data + (addr - s->start);
}
}
sysfatal("fault %.8ux @ %.8ux", addr, P->R[15]);
return nil;
}
void *
vaddrnol(u32int addr)
{
Segment *seg;
void *ret;
ret = vaddr(addr, &seg);
segunlock(seg);
return ret;
}
/* might be made a macro for hurr durr performance */
void
segunlock(Segment *s)
{
if(s->flags & SEGFLLOCK)
runlock(&s->rw);
}
void *
copyifnec(u32int addr, int len, int *copied)
{
void *targ, *ret;
Segment *seg;
targ = vaddr(addr, &seg);
if((seg->flags & SEGFLLOCK) == 0) {
*copied = 0;
return targ;
}
if(len < 0)
len = strlen(targ) + 1;
ret = emalloc(len);
memcpy(ret, targ, len);
segunlock(seg);
*copied = 1;
return ret;
}
void *
bufifnec(u32int addr, int len, int *buffered)
{
void *targ;
Segment *seg;
targ = vaddr(addr, &seg);
if((seg->flags & SEGFLLOCK) == 0) {
*buffered = 0;
return targ;
}
segunlock(seg);
*buffered = 1;
return emalloc(len);
}
void
copyback(u32int addr, int len, void *data)
{
void *targ;
Segment *seg;
if(len <= 0)
return;
targ = vaddr(addr, &seg);
memmove(targ, data, len);
segunlock(seg);
free(data);
}
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