openblt

a hobby OS from the late 90s
git clone http://frotz.net/git/openblt.git
Log | Files | Refs | LICENSE

vnode.c (2107B)


      1 /* $Id: //depot/blt/srv/vfs/vnode.c#4 $
      2 **
      3 ** Copyright 1999 Sidney Cammeresi
      4 ** All rights reserved.
      5 **
      6 ** Redistribution and use in source and binary forms, with or without
      7 ** modification, are permitted provided that the following conditions
      8 ** are met:
      9 ** 1. Redistributions of source code must retain the above copyright
     10 **    notice, this list of conditions, and the following disclaimer.
     11 ** 2. Redistributions in binary form must reproduce the above copyright
     12 **    notice, this list of conditions, and the following disclaimer in the
     13 **    documentation and/or other materials provided with the distribution.
     14 ** 3. The name of the author may not be used to endorse or promote products
     15 **    derived from this software without specific prior written permission.
     16 **
     17 ** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     18 ** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     19 ** OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     20 ** IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     21 ** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     22 ** NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     23 ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     24 ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     25 ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     26 ** THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     27 */
     28 
     29 #include <stdio.h>
     30 #include <stdlib.h>
     31 #include "vfs-int.h"
     32 
     33 struct vnode *vget (struct superblock *super, int vnid)
     34 {
     35 	struct vnode *v;
     36 
     37 #ifdef VNODE_DEBUG
     38 	printf ("vfs: vget %d\n", vnid);
     39 #endif
     40 	v = malloc (sizeof (struct vnode));
     41 	v->v_vnid = vnid;
     42 	v->v_refcount = 1;
     43 	v->v_sb = super;
     44 #ifndef VFS_SANDBOX
     45 	v->v_lock = qsem_create (1);
     46 #endif
     47 	super->sb_vops->read_vnode (v);
     48 	return v;
     49 }
     50 
     51 void vput (struct vnode *vnode)
     52 {
     53 	vnode->v_sb->sb_vops->drop_vnode (vnode);
     54 #ifndef VFS_SANDBOX
     55 	qsem_destroy (vnode->v_lock);
     56 #endif
     57 	vnode->v_refcount--;
     58 	if (!vnode->v_refcount)
     59 		free (vnode);
     60 }
     61