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                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
  83                 if (entry.type != HFS_CDR_THD) {
  84                         printk(KERN_ERR "hfs: bad catalog folder thread\n");
  85                         err = -EIO;
  86                         goto out;
  87                 }
  88                 //if (fd.entrylength < HFS_MIN_THREAD_SZ) {
  89                 //      printk(KERN_ERR "hfs: truncated catalog thread\n");
  90                 //      err = -EIO;
  91                 //      goto out;
  92                 //}
  93                 if (filldir(dirent, "..", 2, 1,
  94                             be32_to_cpu(entry.thread.ParID), DT_DIR))
  95                         goto out;
  96                 filp->f_pos++;
  97                 /* fall through */
  98         default:
  99                 if (filp->f_pos >= inode->i_size)
 100                         goto out;
 101                 err = hfs_brec_goto(&fd, filp->f_pos - 1);
 102                 if (err)
 103                         goto out;
 104         }
 105
 106         for (;;) {
 107                 if (be32_to_cpu(fd.key->cat.ParID) != inode->i_ino) {
 108                         printk(KERN_ERR "hfs: walked past end of dir\n");
 109                         err = -EIO;
 110                         goto out;
 111                 }
 112                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
 113                 type = entry.type;
 114                 len = hfs_mac2asc(sb, strbuf, &fd.key->cat.CName);
 115                 if (type == HFS_CDR_DIR) {
 116                         if (fd.entrylength < sizeof(struct hfs_cat_dir)) {
 117                                 printk(KERN_ERR "hfs: small dir entry\n");
 118                                 err = -EIO;
 119                                 goto out;
 120                         }
 121                         if (filldir(dirent, strbuf, len, filp->f_pos,
 122                                     be32_to_cpu(entry.dir.DirID), DT_DIR))
 123                                 break;
 124                 } else if (type == HFS_CDR_FIL) {
 125                         if (fd.entrylength < sizeof(struct hfs_cat_file)) {
 126                                 printk(KERN_ERR "hfs: small file entry\n");
 127                                 err = -EIO;
 128                                 goto out;
 129                         }
 130                         if (filldir(dirent, strbuf, len, filp->f_pos,
 131                                     be32_to_cpu(entry.file.FlNum), DT_REG))
 132                                 break;
 133                 } else {
 134                         printk(KERN_ERR "hfs: bad catalog entry type %d\n", type);
 135                         err = -EIO;
 136                         goto out;
 137                 }
 138                 filp->f_pos++;
 139                 if (filp->f_pos >= inode->i_size)
 140                         goto out;
 141                 err = hfs_brec_goto(&fd, 1);
 142                 if (err)
 143                         goto out;
 144         }
 145         rd = filp->private_data;
 146         if (!rd) {
 147                 rd = kmalloc(sizeof(struct hfs_readdir_data), GFP_KERNEL);
 148                 if (!rd) {
 149                         err = -ENOMEM;
 150                         goto out;
 151                 }
 152                 filp->private_data = rd;
 153                 rd->file = filp;
 154                 list_add(&rd->list, &HFS_I(inode)->open_dir_list);
 155         }
 156         memcpy(&rd->key, &fd.key, sizeof(struct hfs_cat_key));
 157 out:
 158         hfs_find_exit(&fd);
 159         return err;
 160 }
 161
 162 static int hfs_dir_release(struct inode *inode, struct file *file)
 163 {
 164         struct hfs_readdir_data *rd = file->private_data;
 165         if (rd) {
 166                 list_del(&rd->list);
 167                 kfree(rd);
 168         }
 169         return 0;
 170 }
 171
 172 /*
 173  * hfs_create()
 174  *
 175  * This is the create() entry in the inode_operations structure for
 176  * regular HFS directories.  The purpose is to create a new file in
 177  * a directory and return a corresponding inode, given the inode for
 178  * the directory and the name (and its length) of the new file.
 179  */
 180 static int hfs_create(struct inode *dir, struct dentry *dentry, int mode,
 181                       struct nameidata *nd)
 182 {
 183         struct inode *inode;
 184         int res;
 185
 186         inode = hfs_new_inode(dir, &dentry->d_name, mode);
 187         if (!inode)
 188                 return -ENOSPC;
 189
 190         res = hfs_cat_create(inode->i_ino, dir, &dentry->d_name, inode);
 191         if (res) {
 192                 inode->i_nlink = 0;
 193                 hfs_delete_inode(inode);
 194                 iput(inode);
 195                 return res;
 196         }
 197         d_instantiate(dentry, inode);
 198         mark_inode_dirty(inode);
 199         return 0;
 200 }
 201
 202 /*
 203  * hfs_mkdir()
 204  *
 205  * This is the mkdir() entry in the inode_operations structure for
 206  * regular HFS directories.  The purpose is to create a new directory
 207  * in a directory, given the inode for the parent directory and the
 208  * name (and its length) of the new directory.
 209  */
 210 static int hfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 211 {
 212         struct inode *inode;
 213         int res;
 214
 215         inode = hfs_new_inode(dir, &dentry->d_name, S_IFDIR | mode);
 216         if (!inode)
 217                 return -ENOSPC;
 218
 219         res = hfs_cat_create(inode->i_ino, dir, &dentry->d_name, inode);
 220         if (res) {
 221                 inode->i_nlink = 0;
 222                 hfs_delete_inode(inode);
 223                 iput(inode);
 224                 return res;
 225         }
 226         d_instantiate(dentry, inode);
 227         mark_inode_dirty(inode);
 228         return 0;
 229 }
 230
 231 /*
 232  * hfs_unlink()
 233  *
 234  * This is the unlink() entry in the inode_operations structure for
 235  * regular HFS directories.  The purpose is to delete an existing
 236  * file, given the inode for the parent directory and the name
 237  * (and its length) of the existing file.
 238  */
 239 static int hfs_unlink(struct inode *dir, struct dentry *dentry)
 240 {
 241         struct inode *inode;
 242         int res;
 243
 244         inode = dentry->d_inode;
 245         res = hfs_cat_delete(inode->i_ino, dir, &dentry->d_name);
 246         if (res)
 247                 return res;
 248
 249         drop_nlink(inode);
 250         hfs_delete_inode(inode);
 251         inode->i_ctime = CURRENT_TIME_SEC;
 252         mark_inode_dirty(inode);
 253
 254         return res;
 255 }
 256
 257 /*
 258  * hfs_rmdir()
 259  *
 260  * This is the rmdir() entry in the inode_operations structure for
 261  * regular HFS directories.  The purpose is to delete an existing
 262  * directory, given the inode for the parent directory and the name
 263  * (and its length) of the existing directory.
 264  */
 265 static int hfs_rmdir(struct inode *dir, struct dentry *dentry)
 266 {
 267         struct inode *inode;
 268         int res;
 269
 270         inode = dentry->d_inode;
 271         if (inode->i_size != 2)
 272                 return -ENOTEMPTY;
 273         res = hfs_cat_delete(inode->i_ino, dir, &dentry->d_name);
 274         if (res)
 275                 return res;
 276         clear_nlink(inode);
 277         inode->i_ctime = CURRENT_TIME_SEC;
 278         hfs_delete_inode(inode);
 279         mark_inode_dirty(inode);
 280         return 0;
 281 }
 282
 283 /*
 284  * hfs_rename()
 285  *
 286  * This is the rename() entry in the inode_operations structure for
 287  * regular HFS directories.  The purpose is to rename an existing
 288  * file or directory, given the inode for the current directory and
 289  * the name (and its length) of the existing file/directory and the
 290  * inode for the new directory and the name (and its length) of the
 291  * new file/directory.
 292  * XXX: how do you handle must_be dir?
 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 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 };