fs/9p/fid.h

   1 /*
   2  * V9FS FID Management
   3  *
   4  *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License version 2
   8  *  as published by the Free Software Foundation.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to:
  17  *  Free Software Foundation
  18  *  51 Franklin Street, Fifth Floor
  19  *  Boston, MA  02111-1301  USA
  20  *
  21  */
  22
  23 #include <linux/list.h>
  24
  25 /**
  26  * struct v9fs_dentry - 9p private data stored in dentry d_fsdata
  27  * @lock: protects the fidlist
  28  * @fidlist: list of FIDs currently associated with this dentry
  29  *
  30  * This structure defines the 9p private data associated with
  31  * a particular dentry.  In particular, this private data is used
  32  * to lookup which 9P FID handle should be used for a particular VFS
  33  * operation.  FID handles are associated with dentries instead of
  34  * inodes in order to more closely map functionality to the Plan 9
  35  * expected behavior for FID reclaimation and tracking.
  36  *
  37  * See Also: Mapping FIDs to Linux VFS model in
  38  * Design and Implementation of the Linux 9P File System documentation
  39  */
  40 struct v9fs_dentry {
  41         spinlock_t lock; /* protect fidlist */
  42         struct list_head fidlist;
  43 };
  44
  45 struct p9_fid *v9fs_fid_lookup(struct dentry *dentry);
  46 struct p9_fid *v9fs_fid_clone(struct dentry *dentry);
  47 int v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);