fs/ocfs2/dcache.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * dcache.c
   5  *
   6  * dentry cache handling code
   7  *
   8  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2 of the License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public
  21  * License along with this program; if not, write to the
  22  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23  * Boston, MA 021110-1307, USA.
  24  */
  25
  26 #include <linux/fs.h>
  27 #include <linux/types.h>
  28 #include <linux/slab.h>
  29 #include <linux/namei.h>
  30
  31 #define MLOG_MASK_PREFIX ML_DCACHE
  32 #include <cluster/masklog.h>
  33
  34 #include "ocfs2.h"
  35
  36 #include "alloc.h"
  37 #include "dcache.h"
  38 #include "file.h"
  39 #include "inode.h"
  40
  41 static int ocfs2_dentry_revalidate(struct dentry *dentry,
  42                                    struct nameidata *nd)
  43 {
  44         struct inode *inode = dentry->d_inode;
  45         int ret = 0;    /* if all else fails, just return false */
  46         struct ocfs2_super *osb;
  47
  48         mlog_entry("(0x%p, '%.*s')\n", dentry,
  49                    dentry->d_name.len, dentry->d_name.name);
  50
  51         /* Never trust a negative dentry - force a new lookup. */
  52         if (inode == NULL) {
  53                 mlog(0, "negative dentry: %.*s\n", dentry->d_name.len,
  54                      dentry->d_name.name);
  55                 goto bail;
  56         }
  57
  58         osb = OCFS2_SB(inode->i_sb);
  59
  60         BUG_ON(!osb);
  61
  62         if (inode != osb->root_inode) {
  63                 spin_lock(&OCFS2_I(inode)->ip_lock);
  64                 /* did we or someone else delete this inode? */
  65                 if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_DELETED) {
  66                         spin_unlock(&OCFS2_I(inode)->ip_lock);
  67                         mlog(0, "inode (%"MLFu64") deleted, returning false\n",
  68                              OCFS2_I(inode)->ip_blkno);
  69                         goto bail;
  70                 }
  71                 spin_unlock(&OCFS2_I(inode)->ip_lock);
  72
  73                 if (!inode->i_nlink) {
  74                         mlog(0, "Inode %"MLFu64" orphaned, returning false "
  75                              "dir = %d\n", OCFS2_I(inode)->ip_blkno,
  76                              S_ISDIR(inode->i_mode));
  77                         goto bail;
  78                 }
  79         }
  80
  81         ret = 1;
  82
  83 bail:
  84         mlog_exit(ret);
  85
  86         return ret;
  87 }
  88
  89 struct dentry_operations ocfs2_dentry_ops = {
  90         .d_revalidate           = ocfs2_dentry_revalidate,
  91 };