1/* 2 * 2007+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net> 3 * All rights reserved. 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 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 16#include <linux/module.h> 17#include <linux/fs.h> 18#include <linux/ktime.h> 19#include <linux/fs_struct.h> 20#include <linux/pagemap.h> 21#include <linux/writeback.h> 22#include <linux/mount.h> 23#include <linux/mm.h> 24 25#include "netfs.h" 26 27#define UNHASHED_OBSCURE_STRING_SIZE sizeof(" (deleted)") 28 29/* 30 * Create path from root for given inode. 31 * Path is formed as set of stuctures, containing name of the object 32 * and its inode data (mode, permissions and so on). 33 */ 34int pohmelfs_construct_path_string(struct pohmelfs_inode *pi, void *data, int len) 35{ 36 struct path path; 37 struct dentry *d; 38 char *ptr; 39 int err = 0, strlen, reduce = 0; 40 41 d = d_find_alias(&pi->vfs_inode); 42 if (!d) { 43 printk("%s: no alias, list_empty: %d.\n", __func__, list_empty(&pi->vfs_inode.i_dentry)); 44 return -ENOENT; 45 } 46 47 spin_lock(¤t->fs->lock); 48 path.mnt = mntget(current->fs->root.mnt); 49 spin_unlock(¤t->fs->lock); 50 51 path.dentry = d; 52 53 if (!IS_ROOT(d) && d_unhashed(d)) 54 reduce = 1; 55 56 ptr = d_path(&path, data, len); 57 if (IS_ERR(ptr)) { 58 err = PTR_ERR(ptr); 59 goto out; 60 } 61 62 if (reduce && len >= UNHASHED_OBSCURE_STRING_SIZE) { 63 char *end = data + len - UNHASHED_OBSCURE_STRING_SIZE; 64 *end = '\0'; 65 } 66 67 strlen = len - (ptr - (char *)data); 68 memmove(data, ptr, strlen); 69 ptr = data; 70 71 err = strlen; 72 73 dprintk("%s: dname: '%s', len: %u, maxlen: %u, name: '%s', strlen: %d.\n", 74 __func__, d->d_name.name, d->d_name.len, len, ptr, strlen); 75 76out: 77 dput(d); 78 mntput(path.mnt); 79 80 return err; 81} 82 83int pohmelfs_path_length(struct pohmelfs_inode *pi) 84{ 85 struct dentry *d, *root, *first; 86 int len = 1; /* Root slash */ 87 88 first = d = d_find_alias(&pi->vfs_inode); 89 if (!d) { 90 dprintk("%s: ino: %llu, mode: %o.\n", __func__, pi->ino, pi->vfs_inode.i_mode); 91 return -ENOENT; 92 } 93 94 spin_lock(¤t->fs->lock); 95 root = dget(current->fs->root.dentry); 96 spin_unlock(¤t->fs->lock); 97 98 spin_lock(&dcache_lock); 99 100 if (!IS_ROOT(d) && d_unhashed(d)) 101 len += UNHASHED_OBSCURE_STRING_SIZE; /* Obscure " (deleted)" string */ 102 103 while (d && d != root && !IS_ROOT(d)) { 104 len += d->d_name.len + 1; /* Plus slash */ 105 d = d->d_parent; 106 } 107 spin_unlock(&dcache_lock); 108 109 dput(root); 110 dput(first); 111 112 return len + 1; /* Including zero-byte */ 113} 114