ref: b8b6185f57dca0a64535fd495b436dfb293e9fb3
dir: /fs.c/
#include <u.h>
#include <libc.h>
#include <auth.h>
#include <fcall.h>
#include <avl.h>
#include "dat.h"
#include "fns.h"
#include "atomic.h"
static void respond(Fmsg*, Fcall*);
static void rerror(Fmsg*, char*, ...);
static void clunkfid(Conn*, Fid*, Amsg**);
int
walk1(Tree *t, vlong up, char *name, Qid *qid, vlong *len)
{
char *p, kbuf[Keymax], rbuf[Kvmax];
int err;
Xdir d;
Kvp kv;
Key k;
err = 0;
p = packdkey(kbuf, sizeof(kbuf), up, name);
k.k = kbuf;
k.nk = p - kbuf;
if(err)
return -1;
if(!btlookup(t, &k, &kv, rbuf, sizeof(rbuf)))
return -1;
kv2dir(&kv, &d);
*qid = d.qid;
*len = d.length;
return 0;
}
static void
touch(Dent *de, Msg *msg)
{
wlock(de);
de->qid.vers++;
msg->op = Owstat;
msg->k = de->k;
msg->nk = de->nk;
msg->v = "\0";
msg->nv = 1;
wunlock(de);
}
static void
wrbarrier(void)
{
tracev("barrier", fs->qgen);
aincv(&fs->qgen, 1);
}
static void
wrwait(void)
{
Qent qe;
int i;
tracev("wrwait", fs->qgen);
aincv(&fs->qgen, 1);
fs->syncing = fs->nsyncers;
for(i = 0; i < fs->nsyncers; i++){
qe.op = Qfence;
qe.bp.addr = 0;
qe.bp.hash = -1;
qe.bp.gen = -1;
qe.b = nil;
qput(&fs->syncq[i], qe);
}
aincv(&fs->qgen, 1);
while(fs->syncing != 0)
rsleep(&fs->syncrz);
tracev("flushed", fs->qgen);
}
static void
sync(void)
{
Mount *mnt;
Arena *a;
Dlist dl;
int i;
qlock(&fs->synclk);
if(waserror()){
fprint(2, "failed to sync: %s\n", errmsg());
qunlock(&fs->synclk);
nexterror();
}
/*
* Wait for data that we're syncing to hit disk
*/
tracem("flush1");
wrbarrier();
/*
* pass 0: Update all open snapshots, and
* pack the blocks we want to sync. Snap
* while holding the write lock, and then
* wait until all the blocks they point at
* have hit disk; once they're on disk, we
* can take a consistent snapshot.
*/
qlock(&fs->mutlk);
tracem("packb");
for(mnt = agetp(&fs->mounts); mnt != nil; mnt = mnt->next)
updatesnap(&mnt->root, mnt->root, mnt->name, mnt->flag);
/*
* Now that we've updated the snaps, we can sync the
* dlist; the snap tree will not change from here.
*/
dlsync();
dl = fs->snapdl;
fs->snapdl.hd = Zb;
fs->snapdl.tl = Zb;
fs->snapdl.ins = nil;
traceb("syncdl.dl", dl.hd);
traceb("syncdl.rb", fs->snap.bp);
for(i = 0; i < fs->narena; i++){
a = &fs->arenas[i];
qlock(a);
/*
* because the log uses preallocated
* blocks, we need to write the log
* block out synchronously, or it may
* get reused.
*/
logbarrier(a, fs->qgen);
flushlog(a);
packarena(a->h0->data, Blksz, a);
packarena(a->h1->data, Blksz, a);
finalize(a->h0);
finalize(a->h1);
fs->arenabp[i] = a->h0->bp;
qunlock(a);
}
assert(fs->snapdl.hd.addr == -1);
traceb("packsb.rb", fs->snap.bp);
packsb(fs->sb0->buf, Blksz, fs);
packsb(fs->sb1->buf, Blksz, fs);
finalize(fs->sb0);
finalize(fs->sb1);
fs->snap.dirty = 0;
qunlock(&fs->mutlk);
/*
* pass 1: sync block headers; if we crash here,
* the block footers are consistent, and we can
* use them.
*/
tracem("arenas0");
for(i = 0; i < fs->narena; i++)
enqueue(fs->arenas[i].h0);
wrbarrier();
/*
* pass 2: sync superblock; we have a consistent
* set of block headers, so if we crash, we can
* use the loaded block headers; the footers will
* get synced after so that we can use them next
* time around.
*/
tracem("supers");
enqueue(fs->sb0);
enqueue(fs->sb1);
wrbarrier();
/*
* pass 3: sync block footers; if we crash here,
* the block headers are consistent, and we can
* use them.
*/
tracem("arenas1");
for(i = 0; i < fs->narena; i++)
enqueue(fs->arenas[i].h1);
/*
* Pass 4: clean up the old snap tree's deadlist.
* we need to wait for all the new data to hit disk
* before we can free anything, otherwise it gets
* clobbered.
*/
tracem("snapdl");
wrwait();
freedl(&dl, 1);
qunlock(&fs->synclk);
tracem("synced");
poperror();
}
static void
snapfs(Amsg *a, Tree **tp)
{
Tree *t, *s;
Mount *mnt;
if(waserror()){
*tp = nil;
nexterror();
}
t = nil;
*tp = nil;
for(mnt = agetp(&fs->mounts); mnt != nil; mnt = mnt->next){
if(strcmp(a->old, mnt->name) == 0){
updatesnap(&mnt->root, mnt->root, mnt->name, mnt->flag);
t = agetp(&mnt->root);
ainc(&t->memref);
break;
}
}
if(t == nil && (t = opensnap(a->old, nil)) == nil){
if(a->fd != -1)
fprint(a->fd, "snap: open '%s': does not exist\n", a->old);
poperror();
return;
}
if(a->delete){
if(mnt != nil) {
if(a->fd != -1)
fprint(a->fd, "snap: snap is mounted: '%s'\n", a->old);
poperror();
return;
}
if(t->nlbl == 1 && t->nref <= 1 && t->succ == -1){
aincl(&t->memref, 1);
*tp = t;
}
delsnap(t, t->succ, a->old);
}else{
if((s = opensnap(a->new, nil)) != nil){
if(a->fd != -1)
fprint(a->fd, "snap: already exists '%s'\n", a->new);
closesnap(s);
poperror();
return;
}
tagsnap(t, a->new, a->flag);
}
closesnap(t);
poperror();
if(a->fd != -1){
if(a->delete)
fprint(a->fd, "deleted: %s\n", a->old);
else if(a->flag & Lmut)
fprint(a->fd, "forked: %s from %s\n", a->new, a->old);
else
fprint(a->fd, "labeled: %s from %s\n", a->new, a->old);
}
}
static void
filldumpdir(Xdir *d)
{
memset(d, 0, sizeof(Xdir));
d->name = "/";
d->qid.path = Qdump;
d->qid.vers = fs->nextgen;
d->qid.type = QTDIR;
d->mode = DMDIR|0555;
d->atime = 0;
d->mtime = 0;
d->length = 0;
d->uid = -1;
d->gid = -1;
d->muid = -1;
}
static char*
okname(char *name)
{
int i;
if(name[0] == 0)
return Ename;
if(strcmp(name, ".") == 0 || strcmp(name, "..") == 0)
return Ename;
for(i = 0; i < Maxname; i++){
if(name[i] == 0)
return nil;
if((name[i]&0xff) < 0x20 || name[i] == '/')
return Ename;
}
return Elength;
}
Chan*
mkchan(int size)
{
Chan *c;
if((c = mallocz(sizeof(Chan) + size*sizeof(void*), 1)) == nil)
sysfatal("create channel");
c->size = size;
c->avail = size;
c->count = 0;
c->rp = c->args;
c->wp = c->args;
return c;
}
void*
chrecv(Chan *c)
{
void *a;
long v;
v = agetl(&c->count);
if(v == 0 || !acasl(&c->count, v, v-1))
semacquire(&c->count, 1);
lock(&c->rl);
a = *c->rp;
if(++c->rp >= &c->args[c->size])
c->rp = c->args;
unlock(&c->rl);
semrelease(&c->avail, 1);
return a;
}
void
chsend(Chan *c, void *m)
{
long v;
v = agetl(&c->avail);
if(v == 0 || !acasl(&c->avail, v, v-1))
semacquire(&c->avail, 1);
lock(&c->wl);
*c->wp = m;
if(++c->wp >= &c->args[c->size])
c->wp = c->args;
unlock(&c->wl);
semrelease(&c->count, 1);
}
static void
fshangup(Conn *c, char *fmt, ...)
{
char buf[ERRMAX];
va_list ap;
Amsg *a;
Fid *f;
int i;
va_start(ap, fmt);
vsnprint(buf, sizeof(buf), fmt, ap);
va_end(ap);
fprint(2, "hangup: %s\n", buf);
close(c->rfd);
close(c->wfd);
for(i = 0; i < Nfidtab; i++){
lock(&c->fidtablk[i]);
for(f = c->fidtab[i]; f != nil; f = f->next){
lock(f);
if(waserror()){
unlock(f);
continue;
}
a = nil;
clunkfid(c, f, &a);
unlock(f);
if(a != nil)
chsend(fs->admchan, a);
nexterror();
}
unlock(&c->fidtablk[i]);
}
}
static void
respond(Fmsg *m, Fcall *r)
{
RWLock *lk;
uchar buf[Max9p+IOHDRSZ];
int w, n;
r->tag = m->tag;
dprint("→ %F\n", r);
assert(m->type+1 == r->type || r->type == Rerror);
if((n = convS2M(r, buf, sizeof(buf))) == 0)
abort();
qlock(&m->conn->wrlk);
w = write(m->conn->wfd, buf, n);
qunlock(&m->conn->wrlk);
if(w != n)
fshangup(m->conn, Eio);
if(m->type == Tflush){
lk = &fs->flushq[ihash(m->oldtag) % Nflushtab];
wunlock(lk);
}else{
lk = &fs->flushq[ihash(m->tag) % Nflushtab];
runlock(lk);
}
free(m);
}
static void
rerror(Fmsg *m, char *fmt, ...)
{
char buf[128];
va_list ap;
Fcall r;
va_start(ap, fmt);
vsnprint(buf, sizeof(buf), fmt, ap);
va_end(ap);
r.type = Rerror;
r.ename = buf;
respond(m, &r);
}
static void
upsert(Mount *mnt, Msg *m, int nm)
{
if(!(mnt->flag & Lmut))
error(Erdonly);
if(mnt->root->nlbl != 1 || mnt->root->nref != 0)
updatesnap(&mnt->root, mnt->root, mnt->name, mnt->flag);
btupsert(mnt->root, m, nm);
}
/*
* When truncating a file, mutations need
* to wait for the sweeper to finish; this
* means the mutator needs to release the
* mutation lock, exit the epoch, and
* allow the sweeper to finish its job
* before resuming.
*/
static void
truncwait(Dent *de, int id)
{
epochend(id);
qunlock(&fs->mutlk);
qlock(&de->trunclk);
while(de->trunc)
rsleep(&de->truncrz);
qunlock(&de->trunclk);
qlock(&fs->mutlk);
epochstart(id);
}
static int
readb(Tree *t, Fid *f, char *d, vlong o, vlong n, vlong sz)
{
char buf[Offksz], kvbuf[Offksz+32];
vlong fb, fo;
Bptr bp;
Blk *b;
Key k;
Kvp kv;
if(o >= sz)
return 0;
fb = o & ~(Blksz-1);
fo = o & (Blksz-1);
if(fo+n > Blksz)
n = Blksz-fo;
k.k = buf;
k.nk = sizeof(buf);
k.k[0] = Kdat;
PACK64(k.k+1, f->qpath);
PACK64(k.k+9, fb);
if(!btlookup(t, &k, &kv, kvbuf, sizeof(kvbuf))){
memset(d, 0, n);
return n;
}
bp = unpackbp(kv.v, kv.nv);
b = getblk(bp, GBraw);
memcpy(d, b->buf+fo, n);
dropblk(b);
return n;
}
static int
writeb(Fid *f, Msg *m, Bptr *ret, char *s, vlong o, vlong n, vlong sz)
{
char buf[Kvmax];
vlong fb, fo;
Blk *b, *t;
int seq;
Tree *r;
Bptr bp;
Kvp kv;
fb = o & ~(Blksz-1);
fo = o & (Blksz-1);
m->k[0] = Kdat;
PACK64(m->k+1, f->qpath);
PACK64(m->k+9, fb);
if(fo+n >= Blksz)
seq = 1;
else
seq = 0;
b = newdblk(f->mnt->root, f->qpath, seq);
t = nil;
r = f->mnt->root;
if(btlookup(r, m, &kv, buf, sizeof(buf))){
bp = unpackbp(kv.v, kv.nv);
if(fb < sz && (fo != 0 || n != Blksz)){
t = getblk(bp, GBraw);
memcpy(b->buf, t->buf, Blksz);
dropblk(t);
}
}
if(fo+n > Blksz)
n = Blksz-fo;
memcpy(b->buf+fo, s, n);
if(t == nil){
if(fo > 0)
memset(b->buf, 0, fo);
if(fo+n < Blksz)
memset(b->buf+fo+n, 0, Blksz-fo-n);
}
enqueue(b);
packbp(m->v, m->nv, &b->bp);
*ret = b->bp;
dropblk(b);
return n;
}
static Dent*
getdent(Mount *mnt, vlong pqid, Xdir *d)
{
Dent *de;
char *e;
u32int h;
h = ihash(d->qid.path) % Ndtab;
lock(&mnt->dtablk);
for(de = mnt->dtab[h]; de != nil; de = de->next){
if(de->qid.path == d->qid.path){
ainc(&de->ref);
goto Out;
}
}
de = emalloc(sizeof(Dent), 1);
de->Xdir = *d;
de->ref = 1;
de->up = pqid;
de->qid = d->qid;
de->length = d->length;
de->truncrz.l = &de->trunclk;
if((e = packdkey(de->buf, sizeof(de->buf), pqid, d->name)) == nil){
free(de);
de = nil;
goto Out;
}
de->k = de->buf;
de->nk = e - de->buf;
de->name = de->buf + 11;
de->next = mnt->dtab[h];
mnt->dtab[h] = de;
Out:
unlock(&mnt->dtablk);
return de;
}
static void
loadautos(Mount *mnt)
{
char pfx[128];
int m, h, ns;
uint flg;
Scan s;
m = 0;
h = 0;
pfx[0] = Klabel;
ns = snprint(pfx+1, sizeof(pfx)-1, "%s@minute.", mnt->name);
btnewscan(&s, pfx, ns+1);
btenter(&fs->snap, &s);
while(1){
if(!btnext(&s, &s.kv))
break;
flg = UNPACK32(s.kv.v+1+8);
if(flg & Lauto){
memcpy(mnt->minutely[m], s.kv.k+1, s.kv.nk-1);
mnt->minutely[m][s.kv.nk-1] = 0;
m = (m+1)%60;
continue;
}
}
btexit(&s);
pfx[0] = Klabel;
ns = snprint(pfx+1, sizeof(pfx)-1, "%s@hour.", mnt->name);
btnewscan(&s, pfx, ns+1);
btenter(&fs->snap, &s);
while(1){
if(!btnext(&s, &s.kv))
break;
flg = UNPACK32(s.kv.v+1+8);
if(flg & Lauto){
memcpy(mnt->hourly[h], s.kv.k+1, s.kv.nk-1);
mnt->hourly[h][s.kv.nk-1] = 0;
h = (h+1)%24;
continue;
}
}
btexit(&s);
}
Mount *
getmount(char *name)
{
Mount *mnt;
Tree *t;
int flg;
if(strcmp(name, "dump") == 0){
ainc(&fs->snapmnt->ref);
return fs->snapmnt;
}
qlock(&fs->mountlk);
for(mnt = agetp(&fs->mounts); mnt != nil; mnt = mnt->next){
if(strcmp(name, mnt->name) == 0){
ainc(&mnt->ref);
goto Out;
}
}
if((mnt = mallocz(sizeof(*mnt), 1)) == nil)
error(Enomem);
if(waserror()){
qunlock(&fs->mountlk);
free(mnt);
nexterror();
}
mnt->ref = 1;
snprint(mnt->name, sizeof(mnt->name), "%s", name);
if((t = opensnap(name, &flg)) == nil)
error(Enosnap);
loadautos(mnt);
mnt->flag = flg;
mnt->root = t;
mnt->next = fs->mounts;
asetp(&fs->mounts, mnt);
poperror();
Out:
qunlock(&fs->mountlk);
return mnt;
}
void
clunkmount(Mount *mnt)
{
Mount *me, **p;
if(mnt == nil)
return;
if(adec(&mnt->ref) == 0){
qlock(&fs->mountlk);
for(p = &fs->mounts; (me = *p) != nil; p = &me->next){
if(me == mnt)
break;
}
assert(me != nil);
*p = me->next;
limbo(DFmnt, me);
qunlock(&fs->mountlk);
}
}
static void
clunkdent(Mount *mnt, Dent *de)
{
Dent *e, **pe;
u32int h;
if(de == nil)
return;
if(de->qid.type & QTAUTH && adec(&de->ref) == 0){
free(de);
return;
}
lock(&mnt->dtablk);
if(adec(&de->ref) != 0)
goto Out;
h = ihash(de->qid.path) % Ndtab;
pe = &mnt->dtab[h];
for(e = mnt->dtab[h]; e != nil; e = e->next){
if(e == de)
break;
pe = &e->next;
}
assert(e != nil);
*pe = e->next;
free(de);
Out:
unlock(&mnt->dtablk);
}
static Fid*
getfid(Conn *c, u32int fid)
{
u32int h;
Fid *f;
h = ihash(fid) % Nfidtab;
lock(&c->fidtablk[h]);
for(f = c->fidtab[h]; f != nil; f = f->next)
if(f->fid == fid){
ainc(&f->ref);
break;
}
unlock(&c->fidtablk[h]);
return f;
}
static void
putfid(Fid *f)
{
if(adec(&f->ref) != 0)
return;
clunkdent(f->mnt, f->dent);
clunkdent(f->mnt, f->dir);
clunkmount(f->mnt);
free(f);
}
static Fid*
dupfid(Conn *c, u32int new, Fid *f)
{
Fid *n, *o;
u32int h;
h = ihash(new) % Nfidtab;
if((n = malloc(sizeof(Fid))) == nil)
return nil;
*n = *f;
n->fid = new;
n->ref = 2; /* one for dup, one for clunk */
n->mode = -1;
n->next = nil;
lock(&c->fidtablk[h]);
for(o = c->fidtab[h]; o != nil; o = o->next)
if(o->fid == new)
break;
if(o == nil){
n->next = c->fidtab[h];
c->fidtab[h] = n;
}
unlock(&c->fidtablk[h]);
if(o != nil){
fprint(2, "fid in use: %d == %d\n", o->fid, new);
free(n);
return nil;
}
if(n->mnt != nil)
ainc(&n->mnt->ref);
ainc(&n->dent->ref);
ainc(&n->dir->ref);
setmalloctag(n, getcallerpc(&c));
return n;
}
static void
clunkfid(Conn *c, Fid *fid, Amsg **ao)
{
Fid *f, **pf;
u32int h;
h = ihash(fid->fid) % Nfidtab;
lock(&c->fidtablk[h]);
pf = &c->fidtab[h];
for(f = c->fidtab[h]; f != nil; f = f->next){
if(f == fid){
assert(adec(&f->ref) != 0);
*pf = f->next;
break;
}
pf = &f->next;
}
assert(f != nil);
if(f->scan != nil){
free(f->scan);
f->scan = nil;
}
if(f->rclose != nil){
*ao = f->rclose;
qlock(&f->dent->trunclk);
f->dent->trunc = 1;
qunlock(&f->dent->trunclk);
wlock(f->dent);
f->dent->gone = 1;
wunlock(f->dent);
aincl(&f->dent->ref, 1);
aincl(&f->mnt->ref, 1);
(*ao)->op = AOrclose;
(*ao)->mnt = f->mnt;
(*ao)->qpath = f->qpath;
(*ao)->off = 0;
(*ao)->end = f->dent->length;
(*ao)->dent = f->dent;
}
unlock(&c->fidtablk[h]);
}
static int
readmsg(Conn *c, Fmsg **pm)
{
char szbuf[4];
int sz, n;
Fmsg *m;
n = readn(c->rfd, szbuf, 4);
if(n <= 0){
*pm = nil;
return n;
}
if(n != 4){
werrstr("short read: %r");
return -1;
}
sz = GBIT32(szbuf);
if(sz > c->iounit){
werrstr("message size too large");
return -1;
}
if((m = malloc(sizeof(Fmsg)+sz)) == nil)
return -1;
if(readn(c->rfd, m->buf+4, sz-4) != sz-4){
werrstr("short read: %r");
free(m);
return -1;
}
m->conn = c;
m->sz = sz;
PBIT32(m->buf, sz);
*pm = m;
return 0;
}
static void
fsversion(Fmsg *m)
{
Fcall r;
char *p;
memset(&r, 0, sizeof(Fcall));
p = strchr(m->version, '.');
if(p != nil)
*p = '\0';
r.type = Rversion;
r.msize = Max9p + IOHDRSZ;
if(strcmp(m->version, "9P2000") == 0){
if(m->msize < r.msize)
r.msize = m->msize;
r.version = "9P2000";
m->conn->versioned = 1;
m->conn->iounit = r.msize;
}else{
r.version = "unknown";
m->conn->versioned = 0;
}
respond(m, &r);
}
void
authfree(AuthRpc *auth)
{
AuthRpc *rpc;
if(rpc = auth){
close(rpc->afd);
auth_freerpc(rpc);
}
}
AuthRpc*
authnew(void)
{
static char *keyspec = "proto=p9any role=server";
AuthRpc *rpc;
int fd;
if(access("/mnt/factotum", 0) < 0)
if((fd = open("/srv/factotum", ORDWR)) >= 0)
mount(fd, -1, "/mnt", MBEFORE, "");
if((fd = open("/mnt/factotum/rpc", ORDWR)) < 0)
return nil;
if((rpc = auth_allocrpc(fd)) == nil){
close(fd);
return nil;
}
if(auth_rpc(rpc, "start", keyspec, strlen(keyspec)) != ARok){
authfree(rpc);
return nil;
}
return rpc;
}
static void
authread(Fid *f, Fcall *r, void *data, vlong count)
{
AuthInfo *ai;
AuthRpc *rpc;
User *u;
if((rpc = f->auth) == nil)
error(Etype);
switch(auth_rpc(rpc, "read", nil, 0)){
default:
error(Eauthp);
case ARdone:
if((ai = auth_getinfo(rpc)) == nil)
goto Phase;
rlock(&fs->userlk);
u = name2user(ai->cuid);
auth_freeAI(ai);
if(u == nil){
runlock(&fs->userlk);
error(Enouser);
}
f->uid = u->id;
runlock(&fs->userlk);
return;
case ARok:
if(count < rpc->narg)
error(Eauthd);
memmove(data, rpc->arg, rpc->narg);
r->count = rpc->narg;
return;
case ARphase:
Phase:
error(Eauthph);
}
}
static void
authwrite(Fid *f, Fcall *r, void *data, vlong count)
{
AuthRpc *rpc;
if((rpc = f->auth) == nil)
error(Etype);
if(auth_rpc(rpc, "write", data, count) != ARok)
error(Ebotch);
r->type = Rwrite;
r->count = count;
}
static void
fsauth(Fmsg *m)
{
Dent *de;
Fcall r;
Fid f;
if(fs->noauth){
rerror(m, Eauth);
return;
}
if(strcmp(m->uname, "none") == 0){
rerror(m, Enone);
return;
}
if((de = mallocz(sizeof(Dent), 1)) == nil){
rerror(m, Enomem);
return;
}
memset(de, 0, sizeof(Dent));
de->ref = 0;
de->qid.type = QTAUTH;
de->qid.path = aincv(&fs->nextqid, 1);
de->qid.vers = 0;
de->length = 0;
de->k = nil;
de->nk = 0;
memset(&f, 0, sizeof(Fid));
f.fid = NOFID;
f.mnt = nil;
f.qpath = de->qid.path;
f.pqpath = de->qid.path;
f.mode = -1;
f.iounit = m->conn->iounit;
f.dent = de;
f.dir = de;
f.uid = -1;
f.duid = -1;
f.dgid = -1;
f.dmode = 0600;
f.auth = authnew();
if(dupfid(m->conn, m->afid, &f) == nil){
rerror(m, Efid);
free(de);
return;
}
r.type = Rauth;
r.aqid = de->qid;
respond(m, &r);
}
static int
ingroup(int uid, int gid)
{
User *u, *g;
int i, in;
rlock(&fs->userlk);
in = 0;
u = uid2user(uid);
g = uid2user(gid);
if(u != nil && g != nil)
if(u->id == g->id)
in = 1;
else for(i = 0; i < g->nmemb; i++)
if(u->id == g->memb[i])
in = 1;
runlock(&fs->userlk);
return in;
}
static int
groupleader(int uid, int gid)
{
User *g;
int i, lead;
lead = 0;
rlock(&fs->userlk);
g = uid2user(gid);
if(g != nil){
if(g->lead == 0){
for(i = 0; i < g->nmemb; i++)
if(g->memb[i] == uid){
lead = 1;
break;
}
}else if(uid == g->lead)
lead = 1;
}
runlock(&fs->userlk);
return lead;
}
static int
mode2bits(int req)
{
int m;
m = 0;
switch(req&0xf){
case OREAD: m = DMREAD; break;
case OWRITE: m = DMWRITE; break;
case ORDWR: m = DMREAD|DMWRITE; break;
case OEXEC: m = DMREAD|DMEXEC; break;
}
if(req&OTRUNC)
m |= DMWRITE;
return m;
}
static int
fsaccess(Fid *f, ulong fmode, int fuid, int fgid, int m)
{
/* uid none gets only other permissions */
if(f->permit)
return 0;
if(f->uid != noneid) {
if(f->uid == fuid)
if((m & (fmode>>6)) == m)
return 0;
if(ingroup(f->uid, fgid))
if((m & (fmode>>3)) == m)
return 0;
}
if((m & fmode) == m) {
if((fmode & DMDIR) && (m == DMEXEC))
return 0;
if(!ingroup(f->uid, nogroupid))
return 0;
}
return -1;
}
static void
fsattach(Fmsg *m)
{
char dbuf[Kvmax], kvbuf[Kvmax];
char *p, *n, *aname;
Mount *mnt;
Dent *de;
Tree *t;
User *u;
Fcall r;
Xdir d;
Kvp kv;
Key dk;
Fid f, *af;
int uid;
de = nil;
mnt = nil;
if(waserror()){
rerror(m, errmsg());
goto Err;
}
aname = m->aname;
if(aname[0] == '%')
aname++;
if(aname[0] == '\0')
aname = "main";
if((mnt = getmount(aname)) == nil)
error(Enosnap);
rlock(&fs->userlk);
n = m->uname;
/*
* to allow people to add themselves to the user file,
* we need to force the user id to one that exists.
*/
if(permissive && strcmp(aname, "adm") == 0)
n = "adm";
if((u = name2user(n)) == nil){
runlock(&fs->userlk);
error(Enouser);
}
uid = u->id;
runlock(&fs->userlk);
if(m->afid != NOFID){
r.data = nil;
r.count = 0;
if((af = getfid(m->conn, m->afid)) == nil)
error(Enofid);
authread(af, &r, nil, 0);
putfid(af);
if(af->uid != uid)
error(Ebadu);
}else if(!fs->noauth && strcmp(m->uname, "none") != 0)
error(Ebadu);
if(strcmp(m->aname, "dump") == 0){
memset(&d, 0, sizeof(d));
filldumpdir(&d);
}else{
if((p = packdkey(dbuf, sizeof(dbuf), -1ULL, "")) == nil)
error(Elength);
dk.k = dbuf;
dk.nk = p - dbuf;
t = agetp(&mnt->root);
if(!btlookup(t, &dk, &kv, kvbuf, sizeof(kvbuf)))
error(Enosnap);
kv2dir(&kv, &d);
}
de = getdent(mnt, -1, &d);
memset(&f, 0, sizeof(Fid));
f.fid = NOFID;
f.mnt = mnt;
f.qpath = d.qid.path;
f.pqpath = d.qid.path;
f.mode = -1;
f.iounit = m->conn->iounit;
f.dent = de;
f.dir = de;
f.uid = uid;
f.duid = d.uid;
f.dgid = d.gid;
f.dmode = d.mode;
if(m->aname[0] == '%'){
if(!permissive && !ingroup(uid, admid))
error(Eperm);
f.permit = 1;
}
if(strcmp(aname, "dump") == 0)
f.fromdump = 1;
if(dupfid(m->conn, m->fid, &f) == nil)
error(Efid);
r.type = Rattach;
r.qid = d.qid;
respond(m, &r);
poperror();
Err: clunkdent(mnt, de);
clunkmount(mnt);
}
static int
findparent(Tree *t, vlong up, vlong *qpath, char **name, char *buf, int nbuf)
{
char *p, kbuf[Keymax];
Kvp kv;
Key k;
p = packsuper(kbuf, sizeof(kbuf), up);
k.k = kbuf;
k.nk = p - kbuf;
if(!btlookup(t, &k, &kv, buf, nbuf))
error(Esrch);
*name = unpackdkey(kv.v, kv.nv, qpath);
return 1;
}
static void
dkey(Key *k, vlong up, char *name, char *buf, int nbuf)
{
char *p;
p = packdkey(buf, nbuf, up, name);
k->k = buf;
k->nk = p - buf;
}
static void
fswalk(Fmsg *m)
{
char *name, kbuf[Maxent], kvbuf[Kvmax];
int duid, dgid, dmode;
vlong up, upup, prev;
Dent *dent, *dir;
Fid *o, *f;
Mount *mnt;
Amsg *ao;
Tree *t;
Fcall r;
Xdir d;
Kvp kv;
Key k;
int i;
if((o = getfid(m->conn, m->fid)) == nil){
rerror(m, Enofid);
return;
}
if(waserror()){
rerror(m, errmsg());
putfid(o);
return;
}
if(o->mode != -1)
error(Einuse);
t = o->mnt->root;
mnt = o->mnt;
up = o->pqpath;
prev = o->qpath;
rlock(o->dent);
d = *o->dent;
runlock(o->dent);
duid = d.uid;
dgid = d.gid;
dmode = d.mode;
r.type = Rwalk;
for(i = 0; i < m->nwname; i++){
name = m->wname[i];
if(strlen(name) > Maxname)
error(Elength);
if(fsaccess(o, d.mode, d.uid, d.gid, DMEXEC) != 0)
break;
if(strcmp(name, "..") == 0){
if(up == -1 && o->fromdump){
mnt = fs->snapmnt;
filldumpdir(&d);
prev = -1ULL;
up = -1ULL;
r.wqid[i] = d.qid;
continue;
}
findparent(t, up, &prev, &name, kbuf, sizeof(kbuf));
}else if(d.qid.path == Qdump){
mnt = getmount(m->wname[i]);
name = "";
prev = -1ULL;
t = mnt->root;
}
up = prev;
duid = d.uid;
dgid = d.gid;
dmode = d.mode;
dkey(&k, prev, name, kbuf, sizeof(kbuf));
if(!btlookup(t, &k, &kv, kvbuf, sizeof(kvbuf)))
break;
kv2dir(&kv, &d);
prev = d.qid.path;
r.wqid[i] = d.qid;
}
r.nwqid = i;
if(i == 0 && m->nwname != 0)
error(Esrch);
f = o;
if(m->fid != m->newfid && i == m->nwname){
if((f = dupfid(m->conn, m->newfid, o)) == nil)
error(Efid);
putfid(o);
}
if(i > 0 && i == m->nwname){
lock(f);
ao = nil;
if(waserror()){
if(f != o)
clunkfid(m->conn, f, &ao);
assert(ao == nil);
unlock(f);
nexterror();
}
if(up == -1ULL){
/* the root contains itself, I guess */
dent = getdent(mnt, up, &d);
dir = getdent(mnt, up, &d);
}else{
dent = getdent(mnt, up, &d);
findparent(t, up, &upup, &name, kbuf, sizeof(kbuf));
dkey(&k, upup, name, kbuf, sizeof(kbuf));
if(!btlookup(t, &k, &kv, kvbuf, sizeof(kvbuf)))
broke("missing parent");
kv2dir(&kv, &d);
dir = getdent(mnt, upup, &d);
}
clunkdent(f->mnt, f->dent);
clunkdent(f->mnt, f->dir);
if(mnt != f->mnt){
clunkmount(f->mnt);
ainc(&mnt->ref);
f->mnt = mnt;
}
f->qpath = r.wqid[i-1].path;
f->pqpath = up;
f->dent = dent;
f->dir = dir;
f->duid = duid;
f->dgid = dgid;
f->dmode = dmode;
poperror();
unlock(f);
}
respond(m, &r);
poperror();
putfid(f);
}
static void
fsstat(Fmsg *m)
{
char buf[STATMAX];
Fcall r;
Fid *f;
int n;
if((f = getfid(m->conn, m->fid)) == nil){
rerror(m, Enofid);
return;
}
if(waserror()){
rerror(m, errmsg());
putfid(f);
return;
}
rlock(f->dent);
if((n = dir2statbuf(f->dent, buf, sizeof(buf))) == -1)
error(Efs);
runlock(f->dent);
r.type = Rstat;
r.stat = (uchar*)buf;
r.nstat = n;
respond(m, &r);
poperror();
putfid(f);
}
static void
fswstat(Fmsg *m, int id, Amsg **ao)
{
char rnbuf[Kvmax], opbuf[Kvmax], upbuf[Upksz];
char *p, *e, strs[65535];
int op, nm, rename;
vlong oldlen;
Qid old;
Fcall r;
Dent *de;
Msg mb[4];
Xdir n;
Dir d;
Tree *t;
Fid *f;
Key k;
User *u;
*ao = nil;
rename = 0;
if((f = getfid(m->conn, m->fid)) == nil){
rerror(m, Enofid);
return;
}
de = f->dent;
truncwait(de, id);
wlock(de);
if(waserror()){
rerror(m, errmsg());
free(*ao);
*ao = nil;
goto Err;
}
if(de->gone)
error(Ephase);
if((de->qid.type & QTAUTH) || (de->qid.path & Qdump))
error(Emode);
if(convM2D(m->stat, m->nstat, &d, strs) <= BIT16SZ)
error(Edir);
t = agetp(&f->mnt->root);
n = de->Xdir;
n.qid.vers++;
p = opbuf+1;
op = 0;
/* check validity of updated fields and construct Owstat message */
if(d.qid.path != ~0 || d.qid.vers != ~0){
if(d.qid.path != de->qid.path)
error(Ewstatp);
if(d.qid.vers != de->qid.vers)
error(Ewstatv);
}
if(*d.name != '\0'){
if(strlen(d.name) > Maxname)
error(Elength);
if(strcmp(d.name, de->name) != 0){
rename = 1;
if((e = okname(d.name)) != nil)
error(e);
if(walk1(t, f->dent->up, d.name, &old, &oldlen) == 0)
error(Eexist);
n.name = d.name;
}
}
if(d.length != ~0){
if(d.length < 0)
error(Ewstatl);
if(d.length != de->length){
if(d.length < de->length){
if((*ao = malloc(sizeof(Amsg))) == nil)
error(Enomem);
qlock(&de->trunclk);
de->trunc = 1;
qunlock(&de->trunclk);
aincl(&de->ref, 1);
aincl(&f->mnt->ref, 1);
(*ao)->op = AOclear;
(*ao)->mnt = f->mnt;
(*ao)->qpath = f->qpath;
(*ao)->off = d.length;
(*ao)->end = f->dent->length;
(*ao)->dent = de;
}
de->length = d.length;
n.length = d.length;
op |= Owsize;
PACK64(p, n.length);
p += 8;
}
}
if(d.mode != ~0){
if((d.mode^de->mode) & DMDIR)
error(Ewstatd);
if(d.mode & ~(DMDIR|DMAPPEND|DMEXCL|DMTMP|0777))
error(Ewstatb);
if(d.mode != de->mode){
n.mode = d.mode;
n.qid.type = d.mode>>24;
op |= Owmode;
PACK32(p, n.mode);
p += 4;
}
}
if(d.mtime != ~0){
n.mtime = d.mtime*Nsec;
if(n.mtime != de->mtime){
op |= Owmtime;
PACK64(p, n.mtime);
p += 8;
}
}
if(*d.uid != '\0'){
if(strlen(d.uid) > Maxuname)
error(Elength);
rlock(&fs->userlk);
u = name2user(d.uid);
if(u == nil){
runlock(&fs->userlk);
error(Enouser);
}
n.uid = u->id;
runlock(&fs->userlk);
if(n.uid != de->uid){
op |= Owuid;
PACK32(p, n.uid);
p += 4;
}
}
if(*d.gid != '\0'){
if(strlen(d.gid) > Maxuname)
error(Elength);
rlock(&fs->userlk);
u = name2user(d.gid);
if(u == nil){
runlock(&fs->userlk);
error(Enogrp);
}
n.gid = u->id;
runlock(&fs->userlk);
if(n.gid != de->gid){
op |= Owgid;
PACK32(p, n.gid);
p += 4;
}
}
op |= Owmuid;
n.muid = f->uid;
PACK32(p, n.muid);
p += 4;
/* check permissions */
if(rename)
if(fsaccess(f, f->dmode, f->duid, f->dgid, DMWRITE) == -1)
error(Eperm);
if(op & Owsize)
if(fsaccess(f, de->mode, de->uid, de->gid, DMWRITE) == -1)
error(Eperm);
if(op & (Owmode|Owmtime))
if(!f->permit && f->uid != de->uid && !groupleader(f->uid, de->gid))
error(Ewstato);
if(op & Owuid)
if(!f->permit)
error(Ewstatu);
if(op & Owgid)
if(!f->permit
&& !(f->uid == de->uid && ingroup(f->uid, n.gid))
&& !(groupleader(f->uid, de->gid) && groupleader(f->uid, n.gid)))
error(Ewstatg);
/* update directory entry */
nm = 0;
if(rename && !de->gone){
mb[nm].op = Oclobber;
mb[nm].Key = de->Key;
mb[nm].v = nil;
mb[nm].nv = 0;
nm++;
mb[nm].op = Oinsert;
dir2kv(f->pqpath, &n, &mb[nm], rnbuf, sizeof(rnbuf));
k = mb[nm].Key;
nm++;
if(de->qid.type & QTDIR){
packsuper(upbuf, sizeof(upbuf), f->qpath);
mb[nm].op = Oinsert;
mb[nm].k = upbuf;
mb[nm].nk = Upksz;
mb[nm].v = mb[nm-1].k;
mb[nm].nv = mb[nm-1].nk;
nm++;
}
touch(f->dir, &mb[nm++]);
}else{
opbuf[0] = op;
mb[nm].op = Owstat;
mb[nm].Key = de->Key;
mb[nm].v = opbuf;
mb[nm].nv = p - opbuf;
nm++;
}
assert(nm <= nelem(mb));
upsert(f->mnt, mb, nm);
de->Xdir = n;
if(rename)
cpkey(de, &k, de->buf, sizeof(de->buf));
r.type = Rwstat;
respond(m, &r);
poperror();
Err: wunlock(de);
putfid(f);
}
static void
fsclunk(Fmsg *m, Amsg **ao)
{
Fcall r;
Fid *f;
if((f = getfid(m->conn, m->fid)) == nil){
rerror(m, Enofid);
return;
}
lock(f);
clunkfid(m->conn, f, ao);
unlock(f);
r.type = Rclunk;
respond(m, &r);
putfid(f);
}
static void
fscreate(Fmsg *m)
{
char *p, *e, buf[Kvmax], upkbuf[Keymax], upvbuf[Inlmax];
int nm, duid, dgid, dmode;
Dent *de;
vlong oldlen;
Qid old;
Fcall r;
Msg mb[3];
Fid *f;
Xdir d;
if((e = okname(m->name)) != nil){
rerror(m, e);
return;
}
if(m->perm & (DMMOUNT|DMAUTH)){
rerror(m, Ebotch);
return;
}
if((f = getfid(m->conn, m->fid)) == nil){
rerror(m, Enofid);
return;
}
lock(f);
if(waserror()){
rerror(m, errmsg());
goto Err;
}
if(f->mode != -1){
rerror(m, Einuse);
goto Out;
}
de = f->dent;
if(walk1(f->mnt->root, f->qpath, m->name, &old, &oldlen) == 0){
rerror(m, Eexist);
goto Out;
}
rlock(de);
if(fsaccess(f, de->mode, de->uid, de->gid, DMWRITE) == -1){
rerror(m, Eperm);
runlock(de);
goto Out;
}
duid = de->uid;
dgid = de->gid;
dmode = de->mode;
runlock(de);
nm = 0;
d.qid.type = 0;
if(m->perm & DMDIR)
d.qid.type |= QTDIR;
if(m->perm & DMAPPEND)
d.qid.type |= QTAPPEND;
if(m->perm & DMEXCL)
d.qid.type |= QTEXCL;
if(m->perm & DMTMP)
d.qid.type |= QTTMP;
d.qid.path = aincv(&fs->nextqid, 1);
d.qid.vers = 0;
d.mode = m->perm;
if(m->perm & DMDIR)
d.mode &= ~0777 | de->mode & 0777;
else
d.mode &= ~0666 | de->mode & 0666;
d.name = m->name;
d.atime = nsec();
d.mtime = d.atime;
d.length = 0;
d.uid = f->uid;
d.gid = dgid;
d.muid = f->uid;
mb[nm].op = Oinsert;
dir2kv(f->qpath, &d, &mb[nm], buf, sizeof(buf));
nm++;
if(m->perm & DMDIR){
mb[nm].op = Oinsert;
if((p = packsuper(upkbuf, sizeof(upkbuf), d.qid.path)) == nil)
sysfatal("ream: pack super");
mb[nm].k = upkbuf;
mb[nm].nk = p - upkbuf;
if((p = packdkey(upvbuf, sizeof(upvbuf), f->qpath, d.name)) == nil)
sysfatal("ream: pack super");
mb[nm].v = upvbuf;
mb[nm].nv = p - upvbuf;
nm++;
}
touch(f->dent, &mb[nm++]);
assert(nm <= nelem(mb));
upsert(f->mnt, mb, nm);
de = getdent(f->mnt, f->qpath, &d);
clunkdent(f->mnt, f->dent);
f->mode = mode2bits(m->mode);
f->pqpath = f->qpath;
f->qpath = d.qid.path;
f->dent = de;
f->duid = duid;
f->dgid = dgid;
f->dmode = dmode;
if(m->mode & ORCLOSE)
f->rclose = emalloc(sizeof(Amsg), 1);
r.type = Rcreate;
r.qid = d.qid;
r.iounit = f->iounit;
respond(m, &r);
Out: poperror();
Err: unlock(f);
putfid(f);
return;
}
static char*
candelete(Fid *f)
{
char *e, pfx[Dpfxsz];
Tree *t;
Scan s;
if(!(f->dent->qid.type & QTDIR))
return nil;
t = agetp(&f->mnt->root);
packdkey(pfx, sizeof(pfx), f->qpath, nil);
btnewscan(&s, pfx, sizeof(pfx));
btenter(t, &s);
if(btnext(&s, &s.kv))
e = Enempty;
else
e = nil;
btexit(&s);
return e;
}
static void
fsremove(Fmsg *m, int id, Amsg **ao)
{
char *e, buf[Kvmax];
Fcall r;
int nm;
Msg mb[3];
Tree *t;
Kvp kv;
Fid *f;
if((f = getfid(m->conn, m->fid)) == nil){
rerror(m, Enofid);
return;
}
t = f->mnt->root;
nm = 0;
*ao = nil;
lock(f);
clunkfid(m->conn, f, ao);
/* rclose files are getting removed here anyways */
if(*ao != nil)
f->rclose = nil;
unlock(f);
truncwait(f->dent, id);
wlock(f->dent);
if(waserror()){
rerror(m, errmsg());
free(*ao);
*ao = nil;
goto Err;
}
if(f->dent->gone)
error(Ephase);
/*
* we need a double check that the file is in the tree
* here, because the walk to the fid is done in a reader
* proc that can look it up in a stale version of the
* tree, while we clunk the dent in the mutator proc.
*
* this means we can theoretically get some deletions
* of files that are already gone.
*/
if(!btlookup(t, &f->dent->Key, &kv, buf, sizeof(buf)))
error(Ephase);
if((e = candelete(f)) != nil)
error(e);
if(fsaccess(f, f->dmode, f->duid, f->dgid, DMWRITE) == -1)
error(Eperm);
lock(f);
mb[nm].op = Odelete;
mb[nm].k = f->dent->k;
mb[nm].nk = f->dent->nk;
mb[nm].v = "\0";
mb[nm].nv = 1;
nm++;
unlock(f);
if(f->dent->qid.type & QTDIR){
packsuper(buf, sizeof(buf), f->qpath);
mb[nm].op = Oclobber;
mb[nm].k = buf;
mb[nm].nk = Upksz;
mb[nm].nv = 0;
nm++;
}else{
if(*ao == nil)
*ao = emalloc(sizeof(Amsg), 1);
aincl(&f->mnt->ref, 1);
(*ao)->op = AOclear;
(*ao)->mnt = f->mnt;
(*ao)->qpath = f->qpath;
(*ao)->off = 0;
(*ao)->end = f->dent->length;
(*ao)->dent = nil;
}
touch(f->dir, &mb[nm++]);
assert(nm <= nelem(mb));
upsert(f->mnt, mb, nm);
f->dent->gone = 1;
r.type = Rremove;
respond(m, &r);
poperror();
Err:
wunlock(f->dent);
putfid(f);
return;
}
static void
fsopen(Fmsg *m, int id, Amsg **ao)
{
char *p, *e, buf[Kvmax];
int mbits;
Tree *t;
Fcall r;
Xdir d;
Fid *f;
Kvp kv;
Msg mb;
mbits = mode2bits(m->mode);
if((f = getfid(m->conn, m->fid)) == nil){
rerror(m, Enofid);
return;
}
if(waserror()){
rerror(m, errmsg());
putfid(f);
return;
}
if(m->mode & OTRUNC)
truncwait(f->dent, id);
t = agetp(&f->mnt->root);
if((f->qpath & Qdump) != 0){
filldumpdir(&d);
}else{
if(!btlookup(t, f->dent, &kv, buf, sizeof(buf)))
error(Esrch);
kv2dir(&kv, &d);
}
wlock(f->dent);
if(waserror()){
wunlock(f->dent);
nexterror();
}
if(f->dent->gone)
error(Ephase);
if(f->dent->qid.type & QTEXCL)
if(f->dent->ref != 1)
error(Elocked);
if(m->mode & ORCLOSE)
if((e = candelete(f)) != nil)
error(e);
if(fsaccess(f, d.mode, d.uid, d.gid, mbits) == -1)
error(Eperm);
f->dent->length = d.length;
poperror();
wunlock(f->dent);
r.type = Ropen;
r.qid = d.qid;
r.iounit = f->iounit;
lock(f);
if(f->mode != -1){
unlock(f);
error(Einuse);
}
if((m->mode & OTRUNC) && !(f->dent->mode & DMAPPEND)){
wlock(f->dent);
if(waserror()){
wunlock(f->dent);
free(*ao);
*ao = nil;
nexterror();
}
*ao = emalloc(sizeof(Amsg), 1);
qlock(&f->dent->trunclk);
f->dent->trunc = 1;
qunlock(&f->dent->trunclk);
aincl(&f->dent->ref, 1);
aincl(&f->mnt->ref, 1);
(*ao)->op = AOclear;
(*ao)->mnt = f->mnt;
(*ao)->qpath = f->qpath;
(*ao)->off = 0;
(*ao)->end = f->dent->length;
(*ao)->dent = f->dent;
f->dent->muid = f->uid;
f->dent->qid.vers++;
f->dent->length = 0;
mb.op = Owstat;
p = buf;
p[0] = Owsize|Owmuid; p += 1;
PACK64(p, 0); p += 8;
PACK32(p, f->uid); p += 4;
mb.k = f->dent->k;
mb.nk = f->dent->nk;
mb.v = buf;
mb.nv = p - buf;
upsert(f->mnt, &mb, 1);
wunlock(f->dent);
poperror();
}
f->mode = mode2bits(m->mode);
if(m->mode & ORCLOSE)
f->rclose = emalloc(sizeof(Amsg), 1);
unlock(f);
poperror();
respond(m, &r);
putfid(f);
}
static void
readsnap(Fmsg *m, Fid *f, Fcall *r)
{
char pfx[1], *p;
int n, ns;
Scan *s;
Xdir d;
s = f->scan;
if(s != nil && s->offset != 0 && s->offset != m->offset)
error(Edscan);
if(s == nil || m->offset == 0){
s = emalloc(sizeof(Scan), 1);
pfx[0] = Klabel;
btnewscan(s, pfx, 1);
lock(f);
if(f->scan != nil){
free(f->scan);
}
f->scan = s;
unlock(f);
}
if(s->donescan){
r->count = 0;
return;
}
p = r->data;
n = m->count;
filldumpdir(&d);
if(s->overflow){
memcpy(d.name, s->kv.k+1, s->kv.nk-1);
d.name[s->kv.nk-1] = 0;
d.qid.path = UNPACK64(s->kv.v + 1);
if((ns = dir2statbuf(&d, p, n)) == -1){
r->count = 0;
return;
}
s->overflow = 0;
p += ns;
n -= ns;
}
btenter(&fs->snap, s);
while(1){
if(!btnext(s, &s->kv))
break;
memcpy(d.name, s->kv.k+1, s->kv.nk-1);
d.name[s->kv.nk-1] = 0;
d.qid.path = UNPACK64(s->kv.v + 1);
if((ns = dir2statbuf(&d, p, n)) == -1){
s->overflow = 1;
break;
}
p += ns;
n -= ns;
}
btexit(s);
r->count = p - r->data;
return;
}
static void
readdir(Fmsg *m, Fid *f, Fcall *r)
{
char pfx[Dpfxsz], *p;
int n, ns;
Tree *t;
Scan *s;
s = f->scan;
t = agetp(&f->mnt->root);
if(s != nil && s->offset != 0 && s->offset != m->offset)
error(Edscan);
if(s == nil || m->offset == 0){
s = emalloc(sizeof(Scan), 1);
packdkey(pfx, sizeof(pfx), f->qpath, nil);
btnewscan(s, pfx, sizeof(pfx));
lock(f);
if(f->scan != nil)
free(f->scan);
f->scan = s;
unlock(f);
}
if(s->donescan){
r->count = 0;
return;
}
p = r->data;
n = m->count;
if(s->overflow){
if((ns = kv2statbuf(&s->kv, p, n)) == -1){
r->count = 0;
return;
}
s->overflow = 0;
p += ns;
n -= ns;
}
btenter(t, s);
while(1){
if(!btnext(s, &s->kv))
break;
if((ns = kv2statbuf(&s->kv, p, n)) == -1){
s->overflow = 1;
break;
}
p += ns;
n -= ns;
}
btexit(s);
r->count = p - r->data;
}
static void
readfile(Fmsg *m, Fid *f, Fcall *r)
{
vlong n, c, o;
char *p;
Dent *e;
Tree *t;
e = f->dent;
rlock(e);
if(m->offset > e->length){
runlock(e);
return;
}
p = r->data;
c = m->count;
o = m->offset;
t = agetp(&f->mnt->root);
if(m->offset + m->count > e->length)
c = e->length - m->offset;
while(c != 0){
n = readb(t, f, p, o, c, e->length);
r->count += n;
if(n == 0)
break;
p += n;
o += n;
c -= n;
}
runlock(e);
}
static void
fsread(Fmsg *m)
{
Fcall r;
Fid *f;
if((f = getfid(m->conn, m->fid)) == nil){
rerror(m, Enofid);
return;
}
r.type = Rread;
r.count = 0;
r.data = nil;
if(waserror()){
rerror(m, errmsg());
free(r.data);
putfid(f);
return;
}
r.data = emalloc(m->count, 0);
if(f->dent->qid.type & QTAUTH)
authread(f, &r, r.data, m->count);
else if(f->dent->qid.path == Qdump)
readsnap(m, f, &r);
else if(f->dent->qid.type & QTDIR)
readdir(m, f, &r);
else
readfile(m, f, &r);
respond(m, &r);
free(r.data);
poperror();
putfid(f);
}
static void
fswrite(Fmsg *m, int id)
{
char sbuf[Wstatmax], kbuf[Max9p/Blksz+2][Offksz], vbuf[Max9p/Blksz+2][Ptrsz];
Bptr bp[Max9p/Blksz + 2];
Msg kv[Max9p/Blksz + 2];
vlong n, o, c, w;
int i, j;
char *p;
Fcall r;
Tree *t;
Fid *f;
if((f = getfid(m->conn, m->fid)) == nil){
rerror(m, Enofid);
return;
}
if(!(f->mode & DMWRITE)){
rerror(m, Einuse);
putfid(f);
return;
}
truncwait(f->dent, id);
wlock(f->dent);
if(waserror()){
rerror(m, errmsg());
wunlock(f->dent);
putfid(f);
return;
}
if(f->dent->gone)
error(Ephase);
if(f->dent->qid.type & QTAUTH){
authwrite(f, &r, m->data, m->count);
goto Out;
}
w = 0;
p = m->data;
o = m->offset;
c = m->count;
if(f->dent->mode & DMAPPEND)
o = f->dent->length;
t = agetp(&f->mnt->root);
for(i = 0; c != 0; i++){
assert(i < nelem(kv));
assert(i == 0 || o%Blksz == 0);
kv[i].op = Oinsert;
kv[i].k = kbuf[i];
kv[i].nk = sizeof(kbuf[i]);
kv[i].v = vbuf[i];
kv[i].nv = sizeof(vbuf[i]);
if(waserror()){
if(!fs->rdonly)
for(j = 0; j < i; j++)
freebp(t, bp[j]);
nexterror();
}
n = writeb(f, &kv[i], &bp[i], p, o, c, f->dent->length);
poperror();
w += n;
p += n;
o += n;
c -= n;
}
p = sbuf;
kv[i].op = Owstat;
kv[i].k = f->dent->k;
kv[i].nk = f->dent->nk;
*p++ = 0;
if(o > f->dent->length){
sbuf[0] |= Owsize;
PACK64(p, o);
p += 8;
f->dent->length = m->offset+m->count;
}
sbuf[0] |= Owmtime;
f->dent->mtime = nsec();
PACK64(p, f->dent->mtime);
p += 8;
sbuf[0] |= Owmuid;
PACK32(p, f->uid);
p += 4;
kv[i].v = sbuf;
kv[i].nv = p - sbuf;
upsert(f->mnt, kv, i+1);
r.type = Rwrite;
r.count = w;
Out:
poperror();
respond(m, &r);
wunlock(f->dent);
putfid(f);
}
void
fsflush(Fmsg *m)
{
Fcall r;
r.type = Rflush;
respond(m, &r);
}
Conn *
newconn(int rfd, int wfd)
{
Conn *c;
if((c = mallocz(sizeof(*c), 1)) == nil)
return nil;
c->rfd = rfd;
c->wfd = wfd;
c->iounit = Max9p;
c->next = fs->conns;
lock(&fs->connlk);
fs->conns = c;
unlock(&fs->connlk);
return c;
}
void
runfs(int, void *pc)
{
char err[128];
RWLock *lk;
Amsg *a;
Conn *c;
Fcall r;
Fmsg *m;
u32int h;
c = pc;
while(1){
if(readmsg(c, &m) < 0){
fshangup(c, "read message: %r");
return;
}
if(m == nil)
break;
if(convM2S(m->buf, m->sz, m) == 0){
fshangup(c, "invalid message: %r");
return;
}
if(m->type != Tversion && !c->versioned){
fshangup(c, "version required");
return;
}
dprint("← %F\n", &m->Fcall);
if(m->type == Tflush){
lk = &fs->flushq[ihash(m->oldtag) % Nflushtab];
wlock(lk);
}else{
lk = &fs->flushq[ihash(m->tag) % Nflushtab];
rlock(lk);
}
a = nil;
h = ihash(m->fid) % fs->nreaders;
switch(m->type){
/* sync setup, must not access tree */
case Tversion: fsversion(m); break;
case Tauth: fsauth(m); break;
case Tflush: fsflush(m); break;
case Tclunk: fsclunk(m, &a); break;
/* mutators */
case Tcreate: chsend(fs->wrchan, m); break;
case Twrite: chsend(fs->wrchan, m); break;
case Twstat: chsend(fs->wrchan, m); break;
case Tremove: chsend(fs->wrchan, m); break;
/* reads */
case Tattach: chsend(fs->rdchan[h], m); break;
case Twalk: chsend(fs->rdchan[h], m); break;
case Tread: chsend(fs->rdchan[h], m); break;
case Tstat: chsend(fs->rdchan[h], m); break;
/* both */
case Topen:
if((m->mode & OTRUNC) || (m->mode & ORCLOSE) != 0)
chsend(fs->wrchan, m);
else
chsend(fs->rdchan[h], m);
break;
default:
fprint(2, "unknown message %F\n", &m->Fcall);
snprint(err, sizeof(err), "unknown message: %F", &m->Fcall);
r.type = Rerror;
r.ename = err;
respond(m, &r);
break;
}
assert(estacksz() == 0);
if(a != nil)
chsend(fs->admchan, a);
}
}
void
runmutate(int id, void *)
{
Fmsg *m;
Amsg *a;
Fid *f;
while(1){
a = nil;
m = chrecv(fs->wrchan);
if(fs->rdonly){
/*
* special case: even if Tremove fails, we need
* to clunk the fid.
*/
if(m->type == Tremove){
if((f = getfid(m->conn, m->fid)) == nil){
rerror(m, Enofid);
continue;
}
clunkfid(m->conn, f, &a);
/* read only: ignore rclose */
f->rclose = nil;
free(a);
putfid(f);
}
rerror(m, Erdonly);
continue;
}
qlock(&fs->mutlk);
epochstart(id);
fs->snap.dirty = 1;
switch(m->type){
case Tcreate: fscreate(m); break;
case Twrite: fswrite(m, id); break;
case Twstat: fswstat(m, id, &a); break;
case Tremove: fsremove(m, id, &a); break;
case Topen: fsopen(m, id, &a); break;
default: abort(); break;
}
assert(estacksz() == 0);
epochend(id);
qunlock(&fs->mutlk);
epochclean();
if(a != nil)
chsend(fs->admchan, a);
}
}
void
runread(int id, void *ch)
{
Fmsg *m;
while(1){
m = chrecv(ch);
epochstart(id);
switch(m->type){
case Tattach: fsattach(m); break;
case Twalk: fswalk(m); break;
case Tread: fsread(m); break;
case Tstat: fsstat(m); break;
case Topen: fsopen(m, id, nil); break;
}
assert(estacksz() == 0);
epochend(id);
}
}
void
freetree(Bptr rb, vlong pred)
{
Bptr bp;
Blk *b;
Kvp kv;
int i;
b = getblk(rb, 0);
if(b->type == Tpivot){
for(i = 0; i < b->nval; i++){
getval(b, i, &kv);
bp = unpackbp(kv.v, kv.nv);
freetree(bp, pred);
qlock(&fs->mutlk);
qunlock(&fs->mutlk);
epochclean();
}
}
if(rb.gen > pred)
freebp(nil, rb);
dropblk(b);
}
/*
* Here, we clean epochs frequently, but we run outside of
* an epoch; this is because the caller of this function
* has already waited for an epoch to tick over, there's
* nobody that can be accessing the tree other than us,
* and we just need to keep the limbo list short.
*
* Because this is the last reference to the tree, we don't
* need to hold the mutlk, other than when we free or kill
* blocks via epochclean.
*/
void
sweeptree(Tree *t)
{
char pfx[1];
Scan s;
Bptr bp;
pfx[0] = Kdat;
btnewscan(&s, pfx, 1);
btenter(t, &s);
while(1){
if(!btnext(&s, &s.kv))
break;
bp = unpackbp(s.kv.v, s.kv.nv);
if(bp.gen > t->pred)
freebp(nil, bp);
qlock(&fs->mutlk);
qunlock(&fs->mutlk);
epochclean();
}
btexit(&s);
freetree(t->bp, t->pred);
}
void
runsweep(int id, void*)
{
char buf[Kvmax];
Msg mb[Kvmax/Offksz];
Bptr bp, nb, *oldhd;
int i, nm;
vlong off;
Tree *t;
Arena *a;
Amsg *am;
Blk *b;
if((oldhd = calloc(fs->narena, sizeof(Bptr))) == nil)
sysfatal("malloc log heads");
while(1){
am = chrecv(fs->admchan);
switch(am->op){
case AOsync:
tracem("syncreq");
if(!fs->snap.dirty && !am->halt)
goto Next;
if(agetl(&fs->rdonly))
goto Justhalt;
if(waserror()){
fprint(2, "sync error: %s\n", errmsg());
ainc(&fs->rdonly);
break;
}
if(am->halt)
ainc(&fs->rdonly);
for(i = 0; i < fs->narena; i++){
a = &fs->arenas[i];
oldhd[i].addr = -1;
oldhd[i].hash = -1;
oldhd[i].gen = -1;
qlock(a);
/*
* arbitrary heuristic -- try compressing
* when the log doubles in size.
*/
if(a->nlog >= 2*a->lastlogsz){
oldhd[i] = a->loghd;
epochstart(id);
if(waserror()){
epochend(id);
qunlock(a);
nexterror();
}
compresslog(a);
epochend(id);
poperror();
}
qunlock(a);
epochclean();
}
sync();
for(i = 0; i < fs->narena; i++){
for(bp = oldhd[i]; bp.addr != -1; bp = nb){
qlock(&fs->mutlk);
epochstart(id);
b = getblk(bp, 0);
nb = b->logp;
freeblk(nil, b);
dropblk(b);
epochend(id);
qunlock(&fs->mutlk);
epochclean();
}
}
Justhalt:
if(am->halt){
assert(fs->snapdl.hd.addr == -1);
assert(fs->snapdl.tl.addr == -1);
postnote(PNGROUP, getpid(), "halted");
exits(nil);
}
poperror();
break;
case AOsnap:
tracem("snapreq");
if(agetl(&fs->rdonly)){
fprint(2, "snap on read only fs");
goto Next;
}
if(waserror()){
fprint(2, "taking snap: %s\n", errmsg());
ainc(&fs->rdonly);
break;
}
qlock(&fs->mutlk);
if(waserror()){
qunlock(&fs->mutlk);
nexterror();
}
epochstart(id);
snapfs(am, &t);
epochend(id);
poperror();
qunlock(&fs->mutlk);
sync();
if(t != nil){
epochwait();
sweeptree(t);
closesnap(t);
}
poperror();
break;
case AOrclose:
if(agetl(&fs->rdonly)){
fprint(2, "rclose on read only fs");
goto Next;
}
nm = 0;
mb[nm].op = Odelete;
mb[nm].k = am->dent->k;
mb[nm].nk = am->dent->nk;
mb[nm].nv = 0;
nm++;
if(am->dent->qid.type & QTDIR){
packsuper(buf, sizeof(buf), am->qpath);
mb[nm].op = Oclobber;
mb[nm].k = buf;
mb[nm].nk = Upksz;
mb[nm].nv = 0;
nm++;
}
qlock(&fs->mutlk);
upsert(am->mnt, mb, nm);
qunlock(&fs->mutlk);
/* fallthrough */
case AOclear:
if(agetl(&fs->rdonly)){
fprint(2, "clear on read only fs");
goto Next;
}
tracem("bgclear");
if(waserror()){
fprint(2, "clear file %llx: %s\n", am->qpath, errmsg());
ainc(&fs->rdonly);
break;
}
if(am->dent != nil)
qlock(&am->dent->trunclk);
fs->snap.dirty = 1;
nm = 0;
for(off = am->off; off < am->end; off += Blksz){
mb[nm].op = Oclearb;
mb[nm].k = buf + Offksz * nm;
mb[nm].nk = Offksz;
mb[nm].k[0] = Kdat;
PACK64(mb[nm].k+1, am->qpath);
PACK64(mb[nm].k+9, off);
mb[nm].v = nil;
mb[nm].nv = 0;
if(++nm >= nelem(mb) || off + Blksz >= am->end){
qlock(&fs->mutlk);
if(waserror()){
qunlock(&fs->mutlk);
nexterror();
}
epochstart(id);
upsert(am->mnt, mb, nm);
epochend(id);
qunlock(&fs->mutlk);
epochclean();
poperror();
nm = 0;
}
}
if(am->dent != nil){
am->dent->trunc = 0;
rwakeup(&am->dent->truncrz);
qunlock(&am->dent->trunclk);
clunkdent(am->mnt, am->dent);
}
clunkmount(am->mnt);
poperror();
break;
}
Next:
assert(estacksz() == 0);
free(am);
}
}
void
snapmsg(char *old, char *new, int flg)
{
Amsg *a;
a = emalloc(sizeof(Amsg), 1);
a->op = AOsnap;
a->fd = -1;
a->flag = flg;
strecpy(a->old, a->old+sizeof(a->old), old);
if(new == nil)
a->delete = 1;
else
strecpy(a->new, a->new+sizeof(a->new), new);
chsend(fs->admchan, a);
}
void
runtasks(int, void *)
{
char buf[128];
Tm now, then;
Mount *mnt;
int m, h;
Amsg *a;
m = 0;
h = 0;
tmnow(&then, nil);
tmnow(&now, nil);
while(1){
sleep(5000);
if(fs->rdonly)
continue;
if(waserror()){
fprint(2, "task error: %s\n", errmsg());
continue;
}
a = emalloc(sizeof(Amsg), 1);
a->op = AOsync;
a->halt = 0;
a->fd = -1;
chsend(fs->admchan, a);
tmnow(&now, nil);
for(mnt = agetp(&fs->mounts); mnt != nil; mnt = mnt->next){
if(!(mnt->flag & Ltsnap))
continue;
if(now.yday != then.yday){
snprint(buf, sizeof(buf),
"%s@day.%τ", mnt->name, tmfmt(&now, "YYYY.MM.DD[_]hh:mm:ss"));
snapmsg("main", buf, Lauto);
}
if(now.hour != then.hour){
if(mnt->hourly[h][0] != 0)
snapmsg(mnt->hourly[h], nil, 0);
snprint(mnt->hourly[h], sizeof(mnt->hourly[h]),
"%s@hour.%τ", mnt->name, tmfmt(&now, "YYYY.MM.DD[_]hh:mm:ss"));
snapmsg("main", mnt->hourly[h], Lauto);
}
if(now.min != then.min){
if(mnt->minutely[m][0] != 0)
snapmsg(mnt->minutely[m], nil, 0);
snprint(mnt->minutely[m], sizeof(mnt->minutely[m]),
"%s@minute.%τ", mnt->name, tmfmt(&now, "YYYY.MM.DD[_]hh:mm:ss"));
snapmsg("main", mnt->minutely[m], Lauto);
}
}
if(now.hour != then.hour)
h = (h+1)%24;
if(now.min != then.min)
m = (m+1)%60;
then = now;
poperror();
}
}
void
fixfs(void)
{
char *p, kbuf[2][Keymax], vbuf[Inlmax], kvbuf[Msgmax];
Mount *mnt;
Tree *t;
Msg mb[2];
Kvp kv;
Key k;
if(!force && access("/srv/gefs", AEXIST) == 0)
sysfatal("/srv/gefs already exists: is your fs mounted?");
fprint(2, "getting adm mount...\n");
if((mnt = getmount("adm")) == nil){
sysfatal("failed to get adm mount");
}
t = mnt->root;
p = packsuper(kbuf[0], sizeof(kbuf[0]), 0);
k.k = kbuf[0];
k.nk = p - kbuf[0];
fprint(2, "checking for valid adm root backlink...\n");
if(!btlookup(t, &k, &kv, kvbuf, sizeof(kvbuf))){
sysfatal("no mis-reamed key");
}
mb[0].op = Oinsert;
p = packsuper(kbuf[0], sizeof(kbuf[0]), 1);
mb[0].k = kbuf[0];
mb[0].nk = p - kbuf[0];
p = packdkey(vbuf, sizeof(vbuf), -1, "");
mb[0].v = vbuf;
mb[0].nv = p - vbuf;
mb[1].op = Odelete;
p = packsuper(kbuf[1], sizeof(kbuf[1]), 0);
mb[1].k = kbuf[1];
mb[1].nk = p - kbuf[1];
mb[1].v = nil;
mb[1].nv = 0;
fprint(2, "repairing adm root backlink...\n");
qlock(&fs->mutlk);
btupsert(t, mb, 2);
qunlock(&fs->mutlk);
fprint(2, "syncing changes...\n");
sync();
fprint(2, "done\n");
exits(nil);
}