summaryrefslogtreecommitdiff
path: root/libdiskfs/node-nput.c
blob: 73f6b2c2ea937725f72b9e02ef7f4326c8167b7b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
/*
   Copyright (C) 1999, 2001 Free Software Foundation, Inc.
   Written by Thomas Bushnell, BSG.

   This file is part of the GNU Hurd.

   The GNU Hurd is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2, or (at
   your option) any later version.

   The GNU Hurd is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA. */

#include "priv.h"

/* Unlock node NP and release a hard reference; if this is the last
   hard reference and there are no links to the file then request
   weak references to be dropped.  */
void
diskfs_nput (struct node *np)
{
  struct references result;

  /* While we call the diskfs_try_dropping_softrefs, we need to hold
     one reference.  We use a weak reference for this purpose, which
     we acquire by demoting our hard reference to a weak one.  */
  refcounts_demote (&np->refcounts, &result);

  if (result.hard == 0)
    _diskfs_lastref (np);

  /* Finally get rid of our reference.  */
  refcounts_deref_weak (&np->refcounts, &result);

  if (result.hard == 0 && result.weak == 0)
    diskfs_drop_node (np);
  else
    pthread_mutex_unlock (&np->lock);
}