/* Implement dir_rename as described in <hurd/fs.defs>. */
kern_return_t
diskfs_S_dir_rename (struct protid *fromcred,
char *fromname,
struct protid *tocred,
char *toname,
int excl)
{
struct node *fdp, *tdp, *fnp, *tnp, *tmpnp;
error_t err;
struct dirstat *ds = alloca (diskfs_dirstat_size);
if (!fromcred)
return EOPNOTSUPP;
/* Verify that tocred really is a port to us. */
if (! tocred)
return EXDEV;
if (!strcmp (fromname, ".") || !strcmp (fromname, "..")
|| !strcmp (toname, ".") || !strcmp (toname, ".."))
return EINVAL;
if (tocred->po->shadow_root != fromcred->po->shadow_root)
/* Same translator, but in different shadow trees. */
return EXDEV;
if (diskfs_check_readonly ())
return EROFS;
fdp = fromcred->po->np;
tdp = tocred->po->np;
try_again:
/* Acquire the source; hold a reference to it. This
will prevent anyone from deleting it before we create
the new link. */
mutex_lock (&fdp->lock);
err = diskfs_lookup (fdp, fromname, LOOKUP, &fnp, 0, fromcred);
mutex_unlock (&fdp->lock);
if (err == EAGAIN)
err = EINVAL;
if (err)
return err;
if (S_ISDIR (fnp->dn_stat.st_mode))
{
mutex_unlock (&fnp->lock);
if (!mutex_try_lock (&renamedirlock))
{
diskfs_nrele (fnp);
mutex_lock (&renamedirlock);
goto try_again;
}
err = diskfs_rename_dir (fdp, fnp, fromname, tdp, toname, fromcred,
tocred);
if (diskfs_synchronous)
{
mutex_lock (&fdp->lock);
diskfs_file_update (fdp, 1);
mutex_unlock (&fdp->lock);
mutex_lock (&fnp->lock);
diskfs_file_update (fnp, 1);
mutex_unlock (&fnp->lock);
mutex_lock (&tdp->lock);
diskfs_file_update (tdp, 1);
mutex_unlock (&tdp->lock);
}
diskfs_nrele (fnp);
mutex_unlock (&renamedirlock);
if (!err)
/* MiG won't do this for us, which it ought to. */
mach_port_deallocate (mach_task_self (), tocred->pi.port_right);
return err;
}
mutex_unlock (&fnp->lock);
/* We now hold no locks */
/* Link the node into the new directory. */
mutex_lock (&tdp->lock);
err = diskfs_lookup (tdp, toname, RENAME, &tnp, ds, tocred);
if (err == EAGAIN)
err = EINVAL;
else if (!err && excl)
{
err = EEXIST;
diskfs_nput (tnp);
}
if (err && err != ENOENT)
{
diskfs_drop_dirstat (tdp, ds);
diskfs_nrele (fnp);
mutex_unlock (&tdp->lock);
return err;
}
/* rename("foo", "link-to-foo") is guaranteed to return 0 and
do nothing by Posix. */
if (tnp == fnp)
{
diskfs_drop_dirstat (tdp, ds);
diskfs_nrele (fnp);
diskfs_nput (tnp);
mutex_unlock (&tdp->lock);
mach_port_deallocate (mach_task_self (), tocred->pi.port_right);
return 0;
}
/* rename("foo", dir) should fail. */
if (tnp && S_ISDIR (tnp->dn_stat.st_mode))
{
diskfs_drop_dirstat (tdp, ds);
diskfs_nrele (fnp);
diskfs_nput (tnp);
mutex_unlock (&tdp->lock);
return EISDIR;
}
mutex_lock (&fnp->lock);
/* Increment the link count for the upcoming link */
if (fnp->dn_stat.st_nlink == diskfs_link_max - 1)
{
diskfs_drop_dirstat (tdp, ds);
diskfs_nput (fnp);
if (tnp)
diskfs_nput (tnp);
mutex_unlock (&tdp->lock);
return EMLINK;
}
fnp->dn_stat.st_nlink++;
fnp->dn_set_ctime = 1;
diskfs_node_update (fnp, 1);
if (tnp)
{
err = diskfs_dirrewrite (tdp, tnp, fnp, toname, ds);
if (!err)
{
tnp->dn_stat.st_nlink--;
tnp->dn_set_ctime = 1;
if (diskfs_synchronous)
diskfs_node_update (tnp, 1);
}
diskfs_nput (tnp);
}
else
err = diskfs_direnter (tdp, toname, fnp, ds, tocred);
if (diskfs_synchronous)
diskfs_node_update (tdp, 1);
mutex_unlock (&tdp->lock);
mutex_unlock (&fnp->lock);
if (err)
{
diskfs_nrele (fnp);
return err;
}
/* We now hold no locks */
/* Now we remove the source. Unfortunately, we haven't held
fdp locked (nor could we), so someone else might have already
removed it. */
mutex_lock (&fdp->lock);
err = diskfs_lookup (fdp, fromname, REMOVE, &tmpnp, ds, fromcred);
if (err)
{
diskfs_drop_dirstat (tdp, ds);
mutex_unlock (&fdp->lock);
diskfs_nrele (fnp);
return err;
}
if (tmpnp != fnp)
{
/* This is no longer the node being renamed, so just return. */
diskfs_drop_dirstat (tdp, ds);
diskfs_nput (tmpnp);
diskfs_nrele (fnp);
mutex_unlock (&fdp->lock);
mach_port_deallocate (mach_task_self (), tocred->pi.port_right);
return 0;
}
diskfs_nrele (tmpnp);
err = diskfs_dirremove (fdp, fnp, fromname, ds);
if (diskfs_synchronous)
diskfs_node_update (fdp, 1);
fnp->dn_stat.st_nlink--;
fnp->dn_set_ctime = 1;
if (diskfs_synchronous)
diskfs_node_update (fnp, 1);
diskfs_nput (fnp);
mutex_unlock (&fdp->lock);
if (!err)
mach_port_deallocate (mach_task_self (), tocred->pi.port_right);
return err;
}
/* Implement dir_unlink as described in <hurd/fs.defs>. */
kern_return_t
diskfs_S_dir_unlink (struct protid *dircred,
char *name)
{
struct node *dnp;
struct node *np;
struct dirstat *ds = alloca (diskfs_dirstat_size);
error_t err;
mach_port_t control = MACH_PORT_NULL;
if (!dircred)
return EOPNOTSUPP;
dnp = dircred->po->np;
if (diskfs_check_readonly ())
return EROFS;
pthread_mutex_lock (&dnp->lock);
err = diskfs_lookup (dnp, name, REMOVE, &np, ds, dircred);
if (err == EAGAIN)
err = EPERM; /* 1003.1-1996 5.5.1.4 */
if (err)
{
diskfs_drop_dirstat (dnp, ds);
pthread_mutex_unlock (&dnp->lock);
return err;
}
/* This isn't the BSD behavior, but it is Posix compliant and saves
us on several race conditions.*/
if (S_ISDIR(np->dn_stat.st_mode))
{
if (np == dnp) /* gotta catch '.' */
diskfs_nrele (np);
else
diskfs_nput (np);
diskfs_drop_dirstat (dnp, ds);
pthread_mutex_unlock (&dnp->lock);
return EPERM; /* 1003.1-1996 5.5.1.4 */
}
err = diskfs_dirremove (dnp, np, name, ds);
if (diskfs_synchronous)
diskfs_node_update (dnp, 1);
if (err)
{
diskfs_nput (np);
pthread_mutex_unlock (&dnp->lock);
return err;
}
np->dn_stat.st_nlink--;
np->dn_set_ctime = 1;
if (diskfs_synchronous)
diskfs_node_update (np, 1);
if (np->dn_stat.st_nlink == 0)
fshelp_fetch_control (&np->transbox, &control);
/* This check is necessary because we might get here on an error while
checking the mode on something which happens to be `.'. */
if (np == dnp)
diskfs_nrele (np);
else
diskfs_nput (np);
pthread_mutex_unlock (&dnp->lock);
if (control)
{
fsys_goaway (control, FSYS_GOAWAY_UNLINK);
mach_port_deallocate (mach_task_self (), control);
}
return err;
}
