Merge branch 'omap-pool'

[linux-2.6-omap-h63xx.git] / drivers / staging / pohmelfs / path_entry.c

diff --git a/drivers/staging/pohmelfs/path_entry.c b/drivers/staging/pohmelfs/path_entry.c
new file mode 100644 (file)
index 0000000..3bad888
--- /dev/null
+++ b/drivers/staging/pohmelfs/path_entry.c
@@ -0,0 +1,114 @@
+/*
+ * 2007+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
+ * All rights reserved.
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/ktime.h>
+#include <linux/fs_struct.h>
+#include <linux/pagemap.h>
+#include <linux/writeback.h>
+#include <linux/mount.h>
+#include <linux/mm.h>
+
+#include "netfs.h"
+
+#define UNHASHED_OBSCURE_STRING_SIZE           sizeof(" (deleted)")
+
+/*
+ * Create path from root for given inode.
+ * Path is formed as set of stuctures, containing name of the object
+ * and its inode data (mode, permissions and so on).
+ */
+int pohmelfs_construct_path_string(struct pohmelfs_inode *pi, void *data, int len)
+{
+       struct path path;
+       struct dentry *d;
+       char *ptr;
+       int err = 0, strlen, reduce = 0;
+
+       d = d_find_alias(&pi->vfs_inode);
+       if (!d) {
+               printk("%s: no alias, list_empty: %d.\n", __func__, list_empty(&pi->vfs_inode.i_dentry));
+               return -ENOENT;
+       }
+
+       read_lock(&current->fs->lock);
+       path.mnt = mntget(current->fs->root.mnt);
+       read_unlock(&current->fs->lock);
+
+       path.dentry = d;
+
+       if (!IS_ROOT(d) && d_unhashed(d))
+               reduce = 1;
+
+       ptr = d_path(&path, data, len);
+       if (IS_ERR(ptr)) {
+               err = PTR_ERR(ptr);
+               goto out;
+       }
+
+       if (reduce && len >= UNHASHED_OBSCURE_STRING_SIZE) {
+               char *end = data + len - UNHASHED_OBSCURE_STRING_SIZE;
+               *end = '\0';
+       }
+
+       strlen = len - (ptr - (char *)data);
+       memmove(data, ptr, strlen);
+       ptr = data;
+
+       err = strlen;
+
+       dprintk("%s: dname: '%s', len: %u, maxlen: %u, name: '%s', strlen: %d.\n",
+                       __func__, d->d_name.name, d->d_name.len, len, ptr, strlen);
+
+out:
+       dput(d);
+       mntput(path.mnt);
+
+       return err;
+}
+
+int pohmelfs_path_length(struct pohmelfs_inode *pi)
+{
+       struct dentry *d, *root, *first;
+       int len = 1; /* Root slash */
+
+       first = d = d_find_alias(&pi->vfs_inode);
+       if (!d) {
+               dprintk("%s: ino: %llu, mode: %o.\n", __func__, pi->ino, pi->vfs_inode.i_mode);
+               return -ENOENT;
+       }
+
+       read_lock(&current->fs->lock);
+       root = dget(current->fs->root.dentry);
+       read_unlock(&current->fs->lock);
+
+       spin_lock(&dcache_lock);
+
+       if (!IS_ROOT(d) && d_unhashed(d))
+               len += UNHASHED_OBSCURE_STRING_SIZE; /* Obscure " (deleted)" string */
+
+       while (d && d != root && !IS_ROOT(d)) {
+               len += d->d_name.len + 1; /* Plus slash */
+               d = d->d_parent;
+       }
+       spin_unlock(&dcache_lock);
+
+       dput(root);
+       dput(first);
+
+       return len + 1; /* Including zero-byte */
+}