ref: 7d7e8ae31ac01434c7017afce4eb0a033281a757
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; }