linux/fs/hfs/dir.c
<<
>>
Prefs
   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 */
  20static struct dentry *hfs_lookup(struct inode *dir, struct dentry *dentry,
  21                                 unsigned int flags)
  22{
  23        hfs_cat_rec rec;
  24        struct hfs_find_data fd;
  25        struct inode *inode = NULL;
  26        int res;
  27
  28        hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
  29        hfs_cat_build_key(dir->i_sb, fd.search_key, dir->i_ino, &dentry->d_name);
  30        res = hfs_brec_read(&fd, &rec, sizeof(rec));
  31        if (res) {
  32                hfs_find_exit(&fd);
  33                if (res == -ENOENT) {
  34                        /* No such entry */
  35                        inode = NULL;
  36                        goto done;
  37                }
  38                return ERR_PTR(res);
  39        }
  40        inode = hfs_iget(dir->i_sb, &fd.search_key->cat, &rec);
  41        hfs_find_exit(&fd);
  42        if (!inode)
  43                return ERR_PTR(-EACCES);
  44done:
  45        d_add(dentry, inode);
  46        return NULL;
  47}
  48
  49/*
  50 * hfs_readdir
  51 */
  52static int hfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
  53{
  54        struct inode *inode = filp->f_path.dentry->d_inode;
  55        struct super_block *sb = inode->i_sb;
  56        int len, err;
  57        char strbuf[HFS_MAX_NAMELEN];
  58        union hfs_cat_rec entry;
  59        struct hfs_find_data fd;
  60        struct hfs_readdir_data *rd;
  61        u16 type;
  62
  63        if (filp->f_pos >= inode->i_size)
  64                return 0;
  65
  66        hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
  67        hfs_cat_build_key(sb, fd.search_key, inode->i_ino, NULL);
  68        err = hfs_brec_find(&fd);
  69        if (err)
  70                goto out;
  71
  72        switch ((u32)filp->f_pos) {
  73        case 0:
  74                /* This is completely artificial... */
  75                if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR))
  76                        goto out;
  77                filp->f_pos++;
  78                /* fall through */
  79        case 1:
  80                if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
  81                        err = -EIO;
  82                        goto out;
  83                }
  84
  85                hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
  86                if (entry.type != HFS_CDR_THD) {
  87                        printk(KERN_ERR "hfs: bad catalog folder thread\n");
  88                        err = -EIO;
  89                        goto out;
  90                }
  91                //if (fd.entrylength < HFS_MIN_THREAD_SZ) {
  92                //      printk(KERN_ERR "hfs: truncated catalog thread\n");
  93                //      err = -EIO;
  94                //      goto out;
  95                //}
  96                if (filldir(dirent, "..", 2, 1,
  97                            be32_to_cpu(entry.thread.ParID), DT_DIR))
  98                        goto out;
  99                filp->f_pos++;
 100                /* fall through */
 101        default:
 102                if (filp->f_pos >= inode->i_size)
 103                        goto out;
 104                err = hfs_brec_goto(&fd, filp->f_pos - 1);
 105                if (err)
 106                        goto out;
 107        }
 108
 109        for (;;) {
 110                if (be32_to_cpu(fd.key->cat.ParID) != inode->i_ino) {
 111                        printk(KERN_ERR "hfs: walked past end of dir\n");
 112                        err = -EIO;
 113                        goto out;
 114                }
 115
 116                if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
 117                        err = -EIO;
 118                        goto out;
 119                }
 120
 121                hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
 122                type = entry.type;
 123                len = hfs_mac2asc(sb, strbuf, &fd.key->cat.CName);
 124                if (type == HFS_CDR_DIR) {
 125                        if (fd.entrylength < sizeof(struct hfs_cat_dir)) {
 126                                printk(KERN_ERR "hfs: small dir entry\n");
 127                                err = -EIO;
 128                                goto out;
 129                        }
 130                        if (filldir(dirent, strbuf, len, filp->f_pos,
 131                                    be32_to_cpu(entry.dir.DirID), DT_DIR))
 132                                break;
 133                } else if (type == HFS_CDR_FIL) {
 134                        if (fd.entrylength < sizeof(struct hfs_cat_file)) {
 135                                printk(KERN_ERR "hfs: small file entry\n");
 136                                err = -EIO;
 137                                goto out;
 138                        }
 139                        if (filldir(dirent, strbuf, len, filp->f_pos,
 140                                    be32_to_cpu(entry.file.FlNum), DT_REG))
 141                                break;
 142                } else {
 143                        printk(KERN_ERR "hfs: bad catalog entry type %d\n", type);
 144                        err = -EIO;
 145                        goto out;
 146                }
 147                filp->f_pos++;
 148                if (filp->f_pos >= inode->i_size)
 149                        goto out;
 150                err = hfs_brec_goto(&fd, 1);
 151                if (err)
 152                        goto out;
 153        }
 154        rd = filp->private_data;
 155        if (!rd) {
 156                rd = kmalloc(sizeof(struct hfs_readdir_data), GFP_KERNEL);
 157                if (!rd) {
 158                        err = -ENOMEM;
 159                        goto out;
 160                }
 161                filp->private_data = rd;
 162                rd->file = filp;
 163                list_add(&rd->list, &HFS_I(inode)->open_dir_list);
 164        }
 165        memcpy(&rd->key, &fd.key, sizeof(struct hfs_cat_key));
 166out:
 167        hfs_find_exit(&fd);
 168        return err;
 169}
 170
 171static int hfs_dir_release(struct inode *inode, struct file *file)
 172{
 173        struct hfs_readdir_data *rd = file->private_data;
 174        if (rd) {
 175                list_del(&rd->list);
 176                kfree(rd);
 177        }
 178        return 0;
 179}
 180
 181/*
 182 * hfs_create()
 183 *
 184 * This is the create() entry in the inode_operations structure for
 185 * regular HFS directories.  The purpose is to create a new file in
 186 * a directory and return a corresponding inode, given the inode for
 187 * the directory and the name (and its length) of the new file.
 188 */
 189static int hfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 190                      bool excl)
 191{
 192        struct inode *inode;
 193        int res;
 194
 195        inode = hfs_new_inode(dir, &dentry->d_name, mode);
 196        if (!inode)
 197                return -ENOSPC;
 198
 199        res = hfs_cat_create(inode->i_ino, dir, &dentry->d_name, inode);
 200        if (res) {
 201                clear_nlink(inode);
 202                hfs_delete_inode(inode);
 203                iput(inode);
 204                return res;
 205        }
 206        d_instantiate(dentry, inode);
 207        mark_inode_dirty(inode);
 208        return 0;
 209}
 210
 211/*
 212 * hfs_mkdir()
 213 *
 214 * This is the mkdir() entry in the inode_operations structure for
 215 * regular HFS directories.  The purpose is to create a new directory
 216 * in a directory, given the inode for the parent directory and the
 217 * name (and its length) of the new directory.
 218 */
 219static int hfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 220{
 221        struct inode *inode;
 222        int res;
 223
 224        inode = hfs_new_inode(dir, &dentry->d_name, S_IFDIR | mode);
 225        if (!inode)
 226                return -ENOSPC;
 227
 228        res = hfs_cat_create(inode->i_ino, dir, &dentry->d_name, inode);
 229        if (res) {
 230                clear_nlink(inode);
 231                hfs_delete_inode(inode);
 232                iput(inode);
 233                return res;
 234        }
 235        d_instantiate(dentry, inode);
 236        mark_inode_dirty(inode);
 237        return 0;
 238}
 239
 240/*
 241 * hfs_remove()
 242 *
 243 * This serves as both unlink() and rmdir() in the inode_operations
 244 * structure for regular HFS directories.  The purpose is to delete
 245 * an existing child, given the inode for the parent directory and
 246 * the name (and its length) of the existing directory.
 247 *
 248 * HFS does not have hardlinks, so both rmdir and unlink set the
 249 * link count to 0.  The only difference is the emptiness check.
 250 */
 251static int hfs_remove(struct inode *dir, struct dentry *dentry)
 252{
 253        struct inode *inode = dentry->d_inode;
 254        int res;
 255
 256        if (S_ISDIR(inode->i_mode) && inode->i_size != 2)
 257                return -ENOTEMPTY;
 258        res = hfs_cat_delete(inode->i_ino, dir, &dentry->d_name);
 259        if (res)
 260                return res;
 261        clear_nlink(inode);
 262        inode->i_ctime = CURRENT_TIME_SEC;
 263        hfs_delete_inode(inode);
 264        mark_inode_dirty(inode);
 265        return 0;
 266}
 267
 268/*
 269 * hfs_rename()
 270 *
 271 * This is the rename() entry in the inode_operations structure for
 272 * regular HFS directories.  The purpose is to rename an existing
 273 * file or directory, given the inode for the current directory and
 274 * the name (and its length) of the existing file/directory and the
 275 * inode for the new directory and the name (and its length) of the
 276 * new file/directory.
 277 * XXX: how do you handle must_be dir?
 278 */
 279static int hfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 280                      struct inode *new_dir, struct dentry *new_dentry)
 281{
 282        int res;
 283
 284        /* Unlink destination if it already exists */
 285        if (new_dentry->d_inode) {
 286                res = hfs_remove(new_dir, new_dentry);
 287                if (res)
 288                        return res;
 289        }
 290
 291        res = hfs_cat_move(old_dentry->d_inode->i_ino,
 292                           old_dir, &old_dentry->d_name,
 293                           new_dir, &new_dentry->d_name);
 294        if (!res)
 295                hfs_cat_build_key(old_dir->i_sb,
 296                                  (btree_key *)&HFS_I(old_dentry->d_inode)->cat_key,
 297                                  new_dir->i_ino, &new_dentry->d_name);
 298        return res;
 299}
 300
 301const struct file_operations hfs_dir_operations = {
 302        .read           = generic_read_dir,
 303        .readdir        = hfs_readdir,
 304        .llseek         = generic_file_llseek,
 305        .release        = hfs_dir_release,
 306};
 307
 308const struct inode_operations hfs_dir_inode_operations = {
 309        .create         = hfs_create,
 310        .lookup         = hfs_lookup,
 311        .unlink         = hfs_remove,
 312        .mkdir          = hfs_mkdir,
 313        .rmdir          = hfs_remove,
 314        .rename         = hfs_rename,
 315        .setattr        = hfs_inode_setattr,
 316};
 317
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.