include/sys/fs/lofs_node.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 /*
  27  * Loop-back file information structure.
  28  */
  29
  30 #ifndef _SYS_FS_LOFS_NODE_H
  31 #define _SYS_FS_LOFS_NODE_H
  32
  33 #include <sys/fs/lofs_info.h>
  34
  35 #ifdef  __cplusplus
  36 extern "C" {
  37 #endif
  38
  39 /*
  40  * The lnode is the "inode" for loop-back files.  It contains
  41  * all the information necessary to handle loop-back file on the
  42  * client side.
  43  */
  44 typedef struct lnode {
  45         struct lnode    *lo_next;       /* link for hash chain */
  46         struct vnode    *lo_vp;         /* pointer to real vnode */
  47         uint_t          lo_looping;     /* looping flags (see below) */
  48         struct vnode    *lo_vnode;      /* place holder vnode for file */
  49 } lnode_t;
  50
  51 /*
  52  * Flags used when looping has been detected.
  53  */
  54 #define LO_LOOPING      0x01    /* Looping detected */
  55 #define LO_AUTOLOOP     0x02    /* Autonode looping detected */
  56
  57 /*
  58  * Flag passed to makelonode().
  59  */
  60 #define LOF_FORCE       0x1     /* Force creation of new lnode */
  61
  62 /*
  63  * Convert between vnode and lnode
  64  */
  65 #define ltov(lp)        (((lp)->lo_vnode))
  66 #define vtol(vp)        ((struct lnode *)((vp)->v_data))
  67 #define realvp(vp)      (vtol(vp)->lo_vp)
  68
  69 #ifdef _KERNEL
  70 extern vnode_t *makelonode(vnode_t *, struct loinfo *, int);
  71 extern void freelonode(lnode_t *);
  72 #endif /* _KERNEL */
  73
  74 #ifdef  __cplusplus
  75 }
  76 #endif
  77
  78 #endif  /* _SYS_FS_LOFS_NODE_H */