/*
* get an inode into the cache. if no inode exists for this qid, create one
* from an unused qid/inode map.
*/
Ibuf *
iget(Icache *ic, Qid qid)
{
Imap *m, *me;
Ibuf *b;
/*
* find map entry with same qid.path
*/
for(m = ic->map, me = &ic->map[ic->nino]; m < me; m++)
if(m->inuse && m->qid.path==qid.path){
if(m->qid.vers != qid.vers){
/*
* our info is old, forget it
*/
DPRINT(2, "updating old file %llu.%lu\n",
qid.path, qid.vers);
m->qid = qid;
iupdate(ic, m - ic->map, qid);
}
break;
}
/*
* if an already existing inode, just get it
*/
if(m != me)
return iread(ic, m - ic->map);
/*
* create a new inode, throw out the least recently used inode
* if necessary
*/
m = (Imap*)ic->mlru.lnext;
if(m->inuse){
DPRINT(2, "superceding file %llu.%ld by %llu.%ld\n",
m->qid.path, m->qid.vers, qid.path, qid.vers);
if(iremove(ic, m - ic->map) < 0)
return 0;
}
if(statson)
cfsstat.ninsert++;
/*
* init inode and write to disk
*/
DPRINT(2, "new file %llu.%ld ino %ld\n",
qid.path, qid.vers, m - ic->map);
b = ialloc(ic, m - ic->map);
b->inode.inuse = m->inuse = 1;
b->inode.qid = qid;
b->inode.length = 0x7fffffffffffffffLL;
m->qid = qid;
b->inode.ptr.bno = Notabno;
iwrite(ic, b);
return b;
}
void devfs_remove(struct inode *i)
{
rwlock_acquire(&i->rwl, RWL_WRITER);
i->count=0;
iremove(i);
}
