ref: 7038b412045ad003366804789e7fecaf0552f77c
dir: /used.c/
#include <u.h>
#include <libc.h>
#include "dat.h"
#include "fns.h"
#include "extents.h"
/*
go through all the blocks and write out all the used block numbers
to be used by the checker
Starting from root, walk down each dentry printing out the linked blocks with invalid tags
TODO
check that the file size is matched by the number of blocks
*/
Extents useds = {0};
int chatty9p = 0;
char *devfile = nil;
void *emalloc(u32);
void panic(char *fmt, ...);
void walkdirectory(u64 blkno);
void walkfile(u64 blkno);
int checkdentry(u64 blkno, u8 tag, u64 qpath);
static void
usage(void)
{
fprint(2, "usage: used [-D ] fsfile\n");
exits("usage");
}
void *
mallocu32(u32 sz)
{
return mallocz((ulong)sz, 1);
}
void
main(int argc, char *argv[])
{
u64 size;
Errenv env = {0};
envpp = privalloc();
*envpp = &env;
if(waserror()){
panic(0, "err stack %d: %lux %lux %lux %lux %lux %lux",
env.nlabel,
env.label[0][JMPBUFPC], env.label[1][JMPBUFPC],
env.label[2][JMPBUFPC], env.label[3][JMPBUFPC],
env.label[4][JMPBUFPC], env.label[5][JMPBUFPC]);
}
ARGBEGIN{
default: usage();
case 'D': chatty9p= 8; break;
}ARGEND
if(argc != 1)
usage();
devfile = argv[0];
if(devfile == nil)
sysfatal("no disk file");
if (access(devfile, AREAD) == -1)
sysfatal("%s cannot access device", devfile);
size = devinit(devfile);
if(size == 0)
panic("null size %s", devfile);
if(chatty9p)
print("%s %llud bytes %llud blocks\n", devfile, size, size/Blocksize);
initextents(&useds, "useds", 0, 0, 2, nil, fprint, panic, emalloc);
checkdentry(Bdmagic, Tdentry, Qpmagic);
walkdirectory(Bdroot);
close(devfd);
showextents(1, "", &useds);
exits(0);
}
int
checkvalid(u64 blkno, u8 dtag, u64 dpath, u8 tag, u64 qpath, u16 len)
{
if(dtag != tag || dpath != qpath){
/* if(chatty9p) */
fprint(2, "checkblock invalid %llud tag/path expected %s/%llud actual %s/%llud\n",
blkno, tagnames[tag], qpath, tagnames[dtag], dpath);
fprint(2, "used: %llud\n", blkno);
return 0;
}
if(chatty9p)
print("blkno %llud tag %s\n", blkno, tagnames[dtag]);
// print("%llud\n", blkno);
ufree(&useds, blkno, len);
return 1;
}
int
checkdentry(u64 blkno, u8 tag, u64 qpath)
{
u8 buf[Blocksize];
Dentry *d;
devread(blkno, buf, 1);
d = (Dentry*)buf;
return checkvalid(blkno, d->tag, d->path, tag, qpath, 1);
}
/* not checking the ending path as it would take too long */
void
walkindir(u64 blkno, u16 tag, u16 bottomtag, u64 qpath, u64 *nblocksp)
{
u8 buf[Blocksize], cbuf[Blocksize];
u64 ebuf[Nu64perblock];
Indirect *t;
Data *da;
u64 cblkno, path;
int i;
Dentry *cd;
devread(blkno, buf, 1);
t = (Indirect*)buf;
if(checkvalid(blkno, t->tagi, t->pathi, tag, qpath, 1)){
if(tag == Tind0){
for(i = 0; i<Nindperblock; i++){
cblkno = t->bufa[i];
if(cblkno == 0)
return;
if(bottomtag == Tdentry){
devread(cblkno, cbuf, 1);
cd = (Dentry*)cbuf;
if((cd->mode & DMDIR) > 0)
walkdirectory(cblkno);
else
walkfile(cblkno);
}else{
devread(cblkno, cbuf, 1);
da = (Data*)cbuf;
*nblocksp += da->len;
devread(cblkno+da->len-1, ebuf, 1);
path = ebuf[Dpathidx];
checkvalid(cblkno, da->tag, path, Tdata, qpath, da->len);
}
}
}else{
for(i = 0; i<Nindperblock; i++){
cblkno = t->bufa[i];
if(cblkno == 0)
return;
walkindir(cblkno, tag-1, bottomtag, qpath, nblocksp);
}
}
}
return;
}
void
walkdirectory(u64 blkno)
{
u8 buf[Blocksize], cbuf[Blocksize];
Dentry *d, *cd;
Indirect *it;
u64 cblkno;
int i;
devread(blkno, buf, 1);
d = (Dentry*)buf;
if(chatty9p)
print("walkdirectory %llud tag %s d->path %llud\n",
blkno, tagnames[d->tag], d->path);
if(d->tag != Tdentry || d->path != d->qpath){
if(chatty9p)
print("walkdirectory invalid %llud tag/path expected %s/%llud actual %s/%llud\n",
blkno, tagnames[Tdentry], d->qpath, tagnames[d->tag], d->path);
fprint(2, "%llud\n", blkno);
}else{
// print("%llud\n", blkno);
ufree(&useds, blkno, 1);
}
/* do not list the data blocks used by /a/frees
as they are considered to be free blocks */
if(blkno == Bdfrees)
return;
for(i = 0; i<Ndblock; i++){
cblkno = d->dblocks[i];
if(cblkno == 0)
return;
devread(cblkno, cbuf, 1);
cd = (Dentry*)cbuf;
if((cd->mode & DMDIR) > 0)
walkdirectory(cblkno);
else
walkfile(cblkno);
}
for(i = 0; i<Niblock; i++){
cblkno = d->iblocks[i];
if(cblkno == 0)
return;
devread(cblkno, cbuf, 1);
it = (Indirect*)cbuf;
if(it->tagi == Tind0+i){
walkindir(cblkno, Tind0+i, Tdentry, d->qpath, nil);
}else{
fprint(2, "invalid indir tag %llud\n", cblkno);
fprint(2, "%llud\n", cblkno);
}
}
return;
}
void
walkfile(u64 blkno)
{
u8 buf[Blocksize], cbuf[Blocksize];
u64 ebuf[Nu64perblock], nblocks;
Dentry *d;
Data *ct;
Indirect *it;
u64 cblkno, path;
int i;
devread(blkno, buf, 1);
d = (Dentry*)buf;
if(chatty9p)
print("walkfile %llud tag %s d->qid.path %llud\n",
blkno, tagnames[d->tag], d->qpath);
if(d->tag != Tdentry || d->path != d->qpath){
if(chatty9p)
print("walkfile invalid %llud tag/path expected %s/%llud actual %s/%llud\n",
blkno, tagnames[Tdentry], d->qpath, tagnames[d->tag], d->path);
fprint(2, "%llud\n", blkno);
}else{
// print("%llud\n", blkno);
ufree(&useds, blkno, 1);
}
/* do not list the data blocks used by /a/frees
as they are considered to be free blocks */
if(blkno == Bdfrees)
return;
if(d->size <= Ddatasize)
return;
nblocks = 0;
for(i = 0; i<Ndblock; i++){
cblkno = d->dblocks[i];
if(cblkno == 0)
return;
devread(cblkno, cbuf, 1);
ct = (Data*)cbuf;
nblocks += ct->len;
devread(cblkno+ct->len-1, ebuf, 1);
path = ebuf[Dpathidx];
checkvalid(cblkno, ct->tag, path, Tdata, d->qpath, ct->len);
}
for(i = 0; i<Niblock; i++){
cblkno = d->iblocks[i];
if(cblkno == 0)
return;
devread(cblkno, cbuf, 1);
it = (Indirect*)cbuf;
if(it->tagi == Tind0+i){
walkindir(cblkno, Tind0+i, Tdata, d->qpath, &nblocks);
}else{
fprint(2, "invalid indir tag of block %llud %d %s\n",
cblkno, it->tagi, tagnames[it->tagi]);
fprint(2, "%llud\n", cblkno);
}
}
if(d->size/Maxdatablocksize != nblocks/Maxdatablockunits ||
nlastdatablocks(d->size%Maxdatablocksize) != nblocks%Maxdatablockunits)
fprint(2, "file size %llud is using %llud blocks\n",
d->size, nblocks);
return;
}