ref: bdd385803dcbccdf2750f7259a1784744541dec4
dir: /sys/src/cmd/venti/srv/arenas.c/
#include "stdinc.h"
#include "dat.h"
#include "fns.h"
typedef struct AHash AHash;
/*
* hash table for finding arena's based on their names.
*/
struct AHash
{
AHash *next;
Arena *arena;
};
enum
{
AHashSize = 512
};
static AHash *ahash[AHashSize];
static u32int
hashstr(char *s)
{
u32int h;
int c;
h = 0;
for(; c = *s; s++){
c ^= c << 6;
h += (c << 11) ^ (c >> 1);
c = *s;
h ^= (c << 14) + (c << 7) + (c << 4) + c;
}
return h;
}
int
addarena(Arena *arena)
{
AHash *a;
u32int h;
h = hashstr(arena->name) & (AHashSize - 1);
a = MK(AHash);
if(a == nil)
return -1;
a->arena = arena;
a->next = ahash[h];
ahash[h] = a;
return 0;
}
Arena*
findarena(char *name)
{
AHash *a;
u32int h;
h = hashstr(name) & (AHashSize - 1);
for(a = ahash[h]; a != nil; a = a->next)
if(strcmp(a->arena->name, name) == 0)
return a->arena;
return nil;
}
int
delarena(Arena *arena)
{
AHash *a, *last;
u32int h;
h = hashstr(arena->name) & (AHashSize - 1);
last = nil;
for(a = ahash[h]; a != nil; a = a->next){
if(a->arena == arena){
if(last != nil)
last->next = a->next;
else
ahash[h] = a->next;
free(a);
return 0;
}
last = a;
}
return -1;
}
ArenaPart*
initarenapart(Part *part)
{
AMapN amn;
ArenaPart *ap;
ZBlock *b;
u32int i;
int ok;
b = alloczblock(HeadSize, 0, 0);
if(b == nil || readpart(part, PartBlank, b->data, HeadSize) < 0){
seterr(EAdmin, "can't read arena partition header: %r");
return nil;
}
ap = MKZ(ArenaPart);
if(ap == nil){
freezblock(b);
return nil;
}
ap->part = part;
ok = unpackarenapart(ap, b->data);
freezblock(b);
if(ok < 0){
freearenapart(ap, 0);
return nil;
}
ap->tabbase = (PartBlank + HeadSize + ap->blocksize - 1) & ~(ap->blocksize - 1);
if(ap->version != ArenaPartVersion){
seterr(ECorrupt, "unknown arena partition version %d", ap->version);
freearenapart(ap, 0);
return nil;
}
if(ap->blocksize & (ap->blocksize - 1)){
seterr(ECorrupt, "illegal non-power-of-2 block size %d\n", ap->blocksize);
freearenapart(ap, 0);
return nil;
}
if(ap->tabbase >= ap->arenabase){
seterr(ECorrupt, "arena partition table overlaps with arena storage");
freearenapart(ap, 0);
return nil;
}
ap->tabsize = ap->arenabase - ap->tabbase;
partblocksize(part, ap->blocksize);
ap->size = ap->part->size & ~(u64int)(ap->blocksize - 1);
if(readarenamap(&amn, part, ap->tabbase, ap->tabsize) < 0){
freearenapart(ap, 0);
return nil;
}
ap->narenas = amn.n;
ap->map = amn.map;
if(okamap(ap->map, ap->narenas, ap->arenabase, ap->size, "arena table") < 0){
freearenapart(ap, 0);
return nil;
}
ap->arenas = MKNZ(Arena*, ap->narenas);
for(i = 0; i < ap->narenas; i++){
debugarena = i;
ap->arenas[i] = initarena(part, ap->map[i].start, ap->map[i].stop - ap->map[i].start, ap->blocksize);
if(ap->arenas[i] == nil){
seterr(ECorrupt, "%s: %r", ap->map[i].name);
freearenapart(ap, 1);
return nil;
}
if(namecmp(ap->map[i].name, ap->arenas[i]->name) != 0){
seterr(ECorrupt, "arena name mismatches with expected name: %s vs. %s",
ap->map[i].name, ap->arenas[i]->name);
freearenapart(ap, 1);
return nil;
}
if(findarena(ap->arenas[i]->name)){
seterr(ECorrupt, "duplicate arena name %s in %s",
ap->map[i].name, ap->part->name);
freearenapart(ap, 1);
return nil;
}
}
for(i = 0; i < ap->narenas; i++) {
debugarena = i;
addarena(ap->arenas[i]);
}
debugarena = -1;
return ap;
}
ArenaPart*
newarenapart(Part *part, u32int blocksize, u32int tabsize)
{
ArenaPart *ap;
if(blocksize & (blocksize - 1)){
seterr(ECorrupt, "illegal non-power-of-2 block size %d\n", blocksize);
return nil;
}
ap = MKZ(ArenaPart);
if(ap == nil)
return nil;
ap->version = ArenaPartVersion;
ap->part = part;
ap->blocksize = blocksize;
partblocksize(part, blocksize);
ap->size = part->size & ~(u64int)(blocksize - 1);
ap->tabbase = (PartBlank + HeadSize + blocksize - 1) & ~(blocksize - 1);
ap->arenabase = (ap->tabbase + tabsize + blocksize - 1) & ~(blocksize - 1);
ap->tabsize = ap->arenabase - ap->tabbase;
ap->narenas = 0;
if(wbarenapart(ap) < 0){
freearenapart(ap, 0);
return nil;
}
return ap;
}
int
wbarenapart(ArenaPart *ap)
{
ZBlock *b;
if(okamap(ap->map, ap->narenas, ap->arenabase, ap->size, "arena table") < 0)
return -1;
b = alloczblock(HeadSize, 1, 0);
if(b == nil)
/* ZZZ set error message? */
return -1;
if(packarenapart(ap, b->data) < 0){
seterr(ECorrupt, "can't make arena partition header: %r");
freezblock(b);
return -1;
}
if(writepart(ap->part, PartBlank, b->data, HeadSize) < 0 ||
flushpart(ap->part) < 0){
seterr(EAdmin, "can't write arena partition header: %r");
freezblock(b);
return -1;
}
freezblock(b);
return wbarenamap(ap->map, ap->narenas, ap->part, ap->tabbase, ap->tabsize);
}
void
freearenapart(ArenaPart *ap, int freearenas)
{
int i;
if(ap == nil)
return;
if(freearenas){
for(i = 0; i < ap->narenas; i++){
if(ap->arenas[i] == nil)
continue;
delarena(ap->arenas[i]);
freearena(ap->arenas[i]);
}
}
free(ap->map);
free(ap->arenas);
free(ap);
}
int
okamap(AMap *am, int n, u64int start, u64int stop, char *what)
{
u64int last;
u32int i;
last = start;
for(i = 0; i < n; i++){
if(am[i].start < last){
if(i == 0)
seterr(ECorrupt, "invalid start address in %s", what);
else
seterr(ECorrupt, "overlapping ranges in %s", what);
return -1;
}
if(am[i].stop < am[i].start){
seterr(ECorrupt, "invalid range in %s", what);
return -1;
}
last = am[i].stop;
}
if(last > stop){
seterr(ECorrupt, "invalid ending address in %s", what);
return -1;
}
return 0;
}
int
maparenas(AMap *am, Arena **arenas, int n, char *what)
{
u32int i;
for(i = 0; i < n; i++){
arenas[i] = findarena(am[i].name);
if(arenas[i] == nil){
seterr(EAdmin, "can't find arena '%s' for '%s'\n", am[i].name, what);
return -1;
}
}
return 0;
}
int
readarenamap(AMapN *amn, Part *part, u64int base, u32int size)
{
IFile f;
u32int ok;
if(partifile(&f, part, base, size) < 0)
return -1;
ok = parseamap(&f, amn);
freeifile(&f);
return ok;
}
int
wbarenamap(AMap *am, int n, Part *part, u64int base, u64int size)
{
Fmt f;
ZBlock *b;
b = alloczblock(size, 1, part->blocksize);
if(b == nil)
return -1;
fmtzbinit(&f, b);
if(outputamap(&f, am, n) < 0){
seterr(ECorrupt, "arena set size too small");
freezblock(b);
return -1;
}
if(writepart(part, base, b->data, size) < 0 || flushpart(part) < 0){
seterr(EAdmin, "can't write arena set: %r");
freezblock(b);
return -1;
}
freezblock(b);
return 0;
}
/*
* amap: n '\n' amapelem * n
* n: u32int
* amapelem: name '\t' astart '\t' astop '\n'
* astart, astop: u64int
*/
int
parseamap(IFile *f, AMapN *amn)
{
AMap *am;
u64int v64;
u32int v;
char *s, *t, *flds[4];
int i, n;
/*
* arenas
*/
if(ifileu32int(f, &v) < 0){
seterr(ECorrupt, "syntax error: bad number of elements in %s", f->name);
return -1;
}
n = v;
if(n > MaxAMap){
seterr(ECorrupt, "illegal number of elements %d in %s",
n, f->name);
return -1;
}
am = MKNZ(AMap, n);
if(am == nil){
fprint(2, "out of memory\n");
return -1;
}
for(i = 0; i < n; i++){
s = ifileline(f);
if(s)
t = vtstrdup(s);
else
t = nil;
if(s == nil || getfields(s, flds, 4, 0, "\t") != 3){
fprint(2, "early eof after %d of %d, %s:#%d: %s\n", i, n, f->name, f->pos, t);
free(t);
return -1;
}
free(t);
if(nameok(flds[0]) < 0)
return -1;
namecp(am[i].name, flds[0]);
if(stru64int(flds[1], &v64) < 0){
seterr(ECorrupt, "syntax error: bad arena base address in %s", f->name);
free(am);
return -1;
}
am[i].start = v64;
if(stru64int(flds[2], &v64) < 0){
seterr(ECorrupt, "syntax error: bad arena size in %s", f->name);
free(am);
return -1;
}
am[i].stop = v64;
}
amn->map = am;
amn->n = n;
return 0;
}
int
outputamap(Fmt *f, AMap *am, int n)
{
int i;
if(fmtprint(f, "%ud\n", n) < 0)
return -1;
for(i = 0; i < n; i++)
if(fmtprint(f, "%s\t%llud\t%llud\n", am[i].name, am[i].start, am[i].stop) < 0)
return -1;
return 0;
}