void validchk(uint16_t dev, const char *p)
{
if (!validdev(dev)) {
kputs(p);
kputchar(':');
panic(PANIC_INVD);
}
}
int d_open(uint16_t dev, uint8_t flag)
{
if (!validdev(dev)) {
udata.u_error = ENXIO;
return -1;
}
return ((*dev_tab[major(dev)].dev_open) (minor(dev), flag));
}
int d_ioctl(uint16_t dev, uint16_t request, char *data)
{
int ret;
if (!validdev(dev)) {
udata.u_error = ENXIO;
return -1;
}
ret = (*dev_tab[major(dev)].dev_ioctl) (minor(dev), request, data);
if (ret == -1 && !udata.u_error) // maybe the ioctl routine might set this?
udata.u_error = ENOTTY;
return ret;
}
inoptr i_open(uint16_t dev, uint16_t ino)
{
struct dinode *buf;
inoptr nindex, j;
bool isnew = false;
if(!validdev(dev))
panic("i_open: bad dev");
if(!ino){ /* ino==0 means we want a new one */
isnew = true;
ino = i_alloc(dev);
if(!ino) {
udata.u_error = ENOSPC;
return NULLINODE;
}
}
/* Maybe make this DEBUG only eventually - the fs_tab_get cost
is higher than ideal */
if(ino < ROOTINODE || ino >= (fs_tab_get(dev)->m_fs->s_isize - 2) * 8) {
kputs("i_open: bad inode number\n");
return NULLINODE;
}
nindex = NULLINODE;
for(j=i_tab; j<i_tab+ITABSIZE; j++){
if(!j->c_refs) // free slot?
nindex = j;
if(j->c_dev == dev && j->c_num == ino) {
nindex = j;
goto found;
}
}
/* Not already in the table. */
if(!nindex){ /* No unrefed slots in inode table */
udata.u_error = ENFILE;
return(NULLINODE);
}
buf =(struct dinode *)bread(dev,(ino>>3)+2, 0);
memcpy((char *)&(nindex->c_node), (char *)&(buf[ino & 0x07]), 64);
brelse(buf);
nindex->c_dev = dev;
nindex->c_num = ino;
nindex->c_magic = CMAGIC;
found:
if(isnew) {
if(nindex->c_node.i_nlink || nindex->c_node.i_mode & F_MASK)
goto badino;
} else {
if(!(nindex->c_node.i_nlink && nindex->c_node.i_mode & F_MASK))
goto badino;
}
nindex->c_refs++;
return nindex;
badino:
kputs("i_open: bad disk inode\n");
return NULLINODE;
}
