diff options
Diffstat (limited to 'fs/ecryptfs/dentry.c')
-rw-r--r-- | fs/ecryptfs/dentry.c | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/fs/ecryptfs/dentry.c b/fs/ecryptfs/dentry.c new file mode 100644 index 000000000..63cd2c147 --- /dev/null +++ b/fs/ecryptfs/dentry.c @@ -0,0 +1,92 @@ +/** + * eCryptfs: Linux filesystem encryption layer + * + * Copyright (C) 1997-2003 Erez Zadok + * Copyright (C) 2001-2003 Stony Brook University + * Copyright (C) 2004-2006 International Business Machines Corp. + * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA + * 02111-1307, USA. + */ + +#include <linux/dcache.h> +#include <linux/namei.h> +#include <linux/mount.h> +#include <linux/fs_stack.h> +#include <linux/slab.h> +#include "ecryptfs_kernel.h" + +/** + * ecryptfs_d_revalidate - revalidate an ecryptfs dentry + * @dentry: The ecryptfs dentry + * @flags: lookup flags + * + * Called when the VFS needs to revalidate a dentry. This + * is called whenever a name lookup finds a dentry in the + * dcache. Most filesystems leave this as NULL, because all their + * dentries in the dcache are valid. + * + * Returns 1 if valid, 0 otherwise. + * + */ +static int ecryptfs_d_revalidate(struct dentry *dentry, unsigned int flags) +{ + struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); + int rc = 1; + + if (flags & LOOKUP_RCU) + return -ECHILD; + + if (lower_dentry->d_flags & DCACHE_OP_REVALIDATE) + rc = lower_dentry->d_op->d_revalidate(lower_dentry, flags); + + if (d_really_is_positive(dentry)) { + struct inode *inode = d_inode(dentry); + + fsstack_copy_attr_all(inode, ecryptfs_inode_to_lower(inode)); + if (!inode->i_nlink) + return 0; + } + return rc; +} + +struct kmem_cache *ecryptfs_dentry_info_cache; + +static void ecryptfs_dentry_free_rcu(struct rcu_head *head) +{ + kmem_cache_free(ecryptfs_dentry_info_cache, + container_of(head, struct ecryptfs_dentry_info, rcu)); +} + +/** + * ecryptfs_d_release + * @dentry: The ecryptfs dentry + * + * Called when a dentry is really deallocated. + */ +static void ecryptfs_d_release(struct dentry *dentry) +{ + struct ecryptfs_dentry_info *p = dentry->d_fsdata; + if (p) { + path_put(&p->lower_path); + call_rcu(&p->rcu, ecryptfs_dentry_free_rcu); + } +} + +const struct dentry_operations ecryptfs_dops = { + .d_revalidate = ecryptfs_d_revalidate, + .d_release = ecryptfs_d_release, +}; |