release/src-rt-6.x.4708/linux/linux-2.6.36/fs/hfs/dir.c

   1 /*
   2  *  linux/fs/hfs/dir.c
   3  *
   4  * Copyright (C) 1995-1997  Paul H. Hargrove
   5  * (C) 2003 Ardis Technologies <roman@ardistech.com>
   6  * This file may be distributed under the terms of the GNU General Public License.
   7  *
   8  * This file contains directory-related functions independent of which
   9  * scheme is being used to represent forks.
  10  *
  11  * Based on the minix file system code, (C) 1991, 1992 by Linus Torvalds
  12  */
  13
  14 #include "hfs_fs.h"
  15 #include "btree.h"
  16
  17 /*
  18  * hfs_lookup()
  19  */
  20 static struct dentry *hfs_lookup(struct inode *dir, struct dentry *dentry,
  21                                  struct nameidata *nd)
  22 {
  23         hfs_cat_rec rec;
  24         struct hfs_find_data fd;
  25         struct inode *inode = NULL;
  26         int res;
  27
  28         dentry->d_op = &hfs_dentry_operations;
  29
  30         hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
  31         hfs_cat_build_key(dir->i_sb, fd.search_key, dir->i_ino, &dentry->d_name);
  32         res = hfs_brec_read(&fd, &rec, sizeof(rec));
  33         if (res) {
  34                 hfs_find_exit(&fd);
  35                 if (res == -ENOENT) {
  36                         /* No such entry */
  37                         inode = NULL;
  38                         goto done;
  39                 }
  40                 return ERR_PTR(res);
  41         }
  42         inode = hfs_iget(dir->i_sb, &fd.search_key->cat, &rec);
  43         hfs_find_exit(&fd);
  44         if (!inode)
  45                 return ERR_PTR(-EACCES);
  46 done:
  47         d_add(dentry, inode);
  48         return NULL;
  49 }
  50
  51 /*
  52  * hfs_readdir
  53  */
  54 static int hfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
  55 {
  56         struct inode *inode = filp->f_path.dentry->d_inode;
  57         struct super_block *sb = inode->i_sb;
  58         int len, err;
  59         char strbuf[HFS_MAX_NAMELEN];
  60         union hfs_cat_rec entry;
  61         struct hfs_find_data fd;
  62         struct hfs_readdir_data *rd;
  63         u16 type;
  64
  65         if (filp->f_pos >= inode->i_size)
  66                 return 0;
  67
  68         hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
  69         hfs_cat_build_key(sb, fd.search_key, inode->i_ino, NULL);
  70         err = hfs_brec_find(&fd);
  71         if (err)
  72                 goto out;
  73
  74         switch ((u32)filp->f_pos) {
  75         case 0:
  76                 /* This is completely artificial... */
  77                 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR))
  78                         goto out;
  79                 filp->f_pos++;
  80                 /* fall through */
  81         case 1:
  82                 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
  83                         err = -EIO;
  84                         goto out;
  85                 }
  86
  87                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
  88                 if (entry.type != HFS_CDR_THD) {
  89                         printk(KERN_ERR "hfs: bad catalog folder thread\n");
  90                         err = -EIO;
  91                         goto out;
  92                 }
  93                 //if (fd.entrylength < HFS_MIN_THREAD_SZ) {
  94                 //      printk(KERN_ERR "hfs: truncated catalog thread\n");
  95                 //      err = -EIO;
  96                 //      goto out;
  97                 //}
  98                 if (filldir(dirent, "..", 2, 1,
  99                             be32_to_cpu(entry.thread.ParID), DT_DIR))
 100                         goto out;
 101                 filp->f_pos++;
 102                 /* fall through */
 103         default:
 104                 if (filp->f_pos >= inode->i_size)
 105                         goto out;
 106                 err = hfs_brec_goto(&fd, filp->f_pos - 1);
 107                 if (err)
 108                         goto out;
 109         }
 110
 111         for (;;) {
 112                 if (be32_to_cpu(fd.key->cat.ParID) != inode->i_ino) {
 113                         printk(KERN_ERR "hfs: walked past end of dir\n");
 114                         err = -EIO;
 115                         goto out;
 116                 }
 117
 118                 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
 119                         err = -EIO;
 120                         goto out;
 121                 }
 122
 123                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
 124                 type = entry.type;
 125                 len = hfs_mac2asc(sb, strbuf, &fd.key->cat.CName);
 126                 if (type == HFS_CDR_DIR) {
 127                         if (fd.entrylength < sizeof(struct hfs_cat_dir)) {
 128                                 printk(KERN_ERR "hfs: small dir entry\n");
 129                                 err = -EIO;
 130                                 goto out;
 131                         }
 132                         if (filldir(dirent, strbuf, len, filp->f_pos,
 133                                     be32_to_cpu(entry.dir.DirID), DT_DIR))
 134                                 break;
 135                 } else if (type == HFS_CDR_FIL) {
 136                         if (fd.entrylength < sizeof(struct hfs_cat_file)) {
 137                                 printk(KERN_ERR "hfs: small file entry\n");
 138                                 err = -EIO;
 139                                 goto out;
 140                         }
 141                         if (filldir(dirent, strbuf, len, filp->f_pos,
 142                                     be32_to_cpu(entry.file.FlNum), DT_REG))
 143                                 break;
 144                 } else {
 145                         printk(KERN_ERR "hfs: bad catalog entry type %d\n", type);
 146                         err = -EIO;
 147                         goto out;
 148                 }
 149                 filp->f_pos++;
 150                 if (filp->f_pos >= inode->i_size)
 151                         goto out;
 152                 err = hfs_brec_goto(&fd, 1);
 153                 if (err)
 154                         goto out;
 155         }
 156         rd = filp->private_data;
 157         if (!rd) {
 158                 rd = kmalloc(sizeof(struct hfs_readdir_data), GFP_KERNEL);
 159                 if (!rd) {
 160                         err = -ENOMEM;
 161                         goto out;
 162                 }
 163                 filp->private_data = rd;
 164                 rd->file = filp;
 165                 list_add(&rd->list, &HFS_I(inode)->open_dir_list);
 166         }
 167         memcpy(&rd->key, &fd.key, sizeof(struct hfs_cat_key));
 168 out:
 169         hfs_find_exit(&fd);
 170         return err;
 171 }
 172
 173 static int hfs_dir_release(struct inode *inode, struct file *file)
 174 {
 175         struct hfs_readdir_data *rd = file->private_data;
 176         if (rd) {
 177                 list_del(&rd->list);
 178                 kfree(rd);
 179         }
 180         return 0;
 181 }
 182
 183 /*
 184  * hfs_create()
 185  *
 186  * This is the create() entry in the inode_operations structure for
 187  * regular HFS directories.  The purpose is to create a new file in
 188  * a directory and return a corresponding inode, given the inode for
 189  * the directory and the name (and its length) of the new file.
 190  */
 191 static int hfs_create(struct inode *dir, struct dentry *dentry, int mode,
 192                       struct nameidata *nd)
 193 {
 194         struct inode *inode;
 195         int res;
 196
 197         inode = hfs_new_inode(dir, &dentry->d_name, mode);
 198         if (!inode)
 199                 return -ENOSPC;
 200
 201         res = hfs_cat_create(inode->i_ino, dir, &dentry->d_name, inode);
 202         if (res) {
 203                 inode->i_nlink = 0;
 204                 hfs_delete_inode(inode);
 205                 iput(inode);
 206                 return res;
 207         }
 208         d_instantiate(dentry, inode);
 209         mark_inode_dirty(inode);
 210         return 0;
 211 }
 212
 213 /*
 214  * hfs_mkdir()
 215  *
 216  * This is the mkdir() entry in the inode_operations structure for
 217  * regular HFS directories.  The purpose is to create a new directory
 218  * in a directory, given the inode for the parent directory and the
 219  * name (and its length) of the new directory.
 220  */
 221 static int hfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 222 {
 223         struct inode *inode;
 224         int res;
 225
 226         inode = hfs_new_inode(dir, &dentry->d_name, S_IFDIR | mode);
 227         if (!inode)
 228                 return -ENOSPC;
 229
 230         res = hfs_cat_create(inode->i_ino, dir, &dentry->d_name, inode);
 231         if (res) {
 232                 inode->i_nlink = 0;
 233                 hfs_delete_inode(inode);
 234                 iput(inode);
 235                 return res;
 236         }
 237         d_instantiate(dentry, inode);
 238         mark_inode_dirty(inode);
 239         return 0;
 240 }
 241
 242 /*
 243  * hfs_unlink()
 244  *
 245  * This is the unlink() entry in the inode_operations structure for
 246  * regular HFS directories.  The purpose is to delete an existing
 247  * file, given the inode for the parent directory and the name
 248  * (and its length) of the existing file.
 249  */
 250 static int hfs_unlink(struct inode *dir, struct dentry *dentry)
 251 {
 252         struct inode *inode;
 253         int res;
 254
 255         inode = dentry->d_inode;
 256         res = hfs_cat_delete(inode->i_ino, dir, &dentry->d_name);
 257         if (res)
 258                 return res;
 259
 260         drop_nlink(inode);
 261         hfs_delete_inode(inode);
 262         inode->i_ctime = CURRENT_TIME_SEC;
 263         mark_inode_dirty(inode);
 264
 265         return res;
 266 }
 267
 268 /*
 269  * hfs_rmdir()
 270  *
 271  * This is the rmdir() entry in the inode_operations structure for
 272  * regular HFS directories.  The purpose is to delete an existing
 273  * directory, given the inode for the parent directory and the name
 274  * (and its length) of the existing directory.
 275  */
 276 static int hfs_rmdir(struct inode *dir, struct dentry *dentry)
 277 {
 278         struct inode *inode;
 279         int res;
 280
 281         inode = dentry->d_inode;
 282         if (inode->i_size != 2)
 283                 return -ENOTEMPTY;
 284         res = hfs_cat_delete(inode->i_ino, dir, &dentry->d_name);
 285         if (res)
 286                 return res;
 287         clear_nlink(inode);
 288         inode->i_ctime = CURRENT_TIME_SEC;
 289         hfs_delete_inode(inode);
 290         mark_inode_dirty(inode);
 291         return 0;
 292 }
 293
 294 static int hfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 295                       struct inode *new_dir, struct dentry *new_dentry)
 296 {
 297         int res;
 298
 299         /* Unlink destination if it already exists */
 300         if (new_dentry->d_inode) {
 301                 res = hfs_unlink(new_dir, new_dentry);
 302                 if (res)
 303                         return res;
 304         }
 305
 306         res = hfs_cat_move(old_dentry->d_inode->i_ino,
 307                            old_dir, &old_dentry->d_name,
 308                            new_dir, &new_dentry->d_name);
 309         if (!res)
 310                 hfs_cat_build_key(old_dir->i_sb,
 311                                   (btree_key *)&HFS_I(old_dentry->d_inode)->cat_key,
 312                                   new_dir->i_ino, &new_dentry->d_name);
 313         return res;
 314 }
 315
 316 const struct file_operations hfs_dir_operations = {
 317         .read           = generic_read_dir,
 318         .readdir        = hfs_readdir,
 319         .llseek         = generic_file_llseek,
 320         .release        = hfs_dir_release,
 321 };
 322
 323 const struct inode_operations hfs_dir_inode_operations = {
 324         .create         = hfs_create,
 325         .lookup         = hfs_lookup,
 326         .unlink         = hfs_unlink,
 327         .mkdir          = hfs_mkdir,
 328         .rmdir          = hfs_rmdir,
 329         .rename         = hfs_rename,
 330         .setattr        = hfs_inode_setattr,
 331 };