release/src-rt-6.x.4708/linux/linux-2.6.36/fs/9p/vfs_dentry.c

   1 /*
   2  *  linux/fs/9p/vfs_dentry.c
   3  *
   4  * This file contians vfs dentry ops for the 9P2000 protocol.
   5  *
   6  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
   7  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License version 2
  11  *  as published by the Free Software Foundation.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to:
  20  *  Free Software Foundation
  21  *  51 Franklin Street, Fifth Floor
  22  *  Boston, MA  02111-1301  USA
  23  *
  24  */
  25
  26 #include <linux/module.h>
  27 #include <linux/errno.h>
  28 #include <linux/fs.h>
  29 #include <linux/file.h>
  30 #include <linux/pagemap.h>
  31 #include <linux/stat.h>
  32 #include <linux/string.h>
  33 #include <linux/inet.h>
  34 #include <linux/namei.h>
  35 #include <linux/idr.h>
  36 #include <linux/sched.h>
  37 #include <linux/slab.h>
  38 #include <net/9p/9p.h>
  39 #include <net/9p/client.h>
  40
  41 #include "v9fs.h"
  42 #include "v9fs_vfs.h"
  43 #include "fid.h"
  44
  45 /**
  46  * v9fs_dentry_delete - called when dentry refcount equals 0
  47  * @dentry:  dentry in question
  48  *
  49  * By returning 1 here we should remove cacheing of unused
  50  * dentry components.
  51  *
  52  */
  53
  54 static int v9fs_dentry_delete(struct dentry *dentry)
  55 {
  56         P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_name.name,
  57                                                                         dentry);
  58
  59         return 1;
  60 }
  61
  62 /**
  63  * v9fs_cached_dentry_delete - called when dentry refcount equals 0
  64  * @dentry:  dentry in question
  65  *
  66  * Only return 1 if our inode is invalid.  Only non-synthetic files
  67  * (ones without mtime == 0) should be calling this function.
  68  *
  69  */
  70
  71 static int v9fs_cached_dentry_delete(struct dentry *dentry)
  72 {
  73         struct inode *inode = dentry->d_inode;
  74         P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_name.name,
  75                                                                         dentry);
  76
  77         if(!inode)
  78                 return 1;
  79
  80         return 0;
  81 }
  82
  83 /**
  84  * v9fs_dentry_release - called when dentry is going to be freed
  85  * @dentry:  dentry that is being release
  86  *
  87  */
  88
  89 void v9fs_dentry_release(struct dentry *dentry)
  90 {
  91         struct v9fs_dentry *dent;
  92         struct p9_fid *temp, *current_fid;
  93
  94         P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_name.name,
  95                                                                         dentry);
  96         dent = dentry->d_fsdata;
  97         if (dent) {
  98                 list_for_each_entry_safe(current_fid, temp, &dent->fidlist,
  99                                                                         dlist) {
 100                         p9_client_clunk(current_fid);
 101                 }
 102
 103                 kfree(dent);
 104                 dentry->d_fsdata = NULL;
 105         }
 106 }
 107
 108 const struct dentry_operations v9fs_cached_dentry_operations = {
 109         .d_delete = v9fs_cached_dentry_delete,
 110         .d_release = v9fs_dentry_release,
 111 };
 112
 113 const struct dentry_operations v9fs_dentry_operations = {
 114         .d_delete = v9fs_dentry_delete,
 115         .d_release = v9fs_dentry_release,
 116 };