fs/hfs/catalog.c

   1 /*
   2  *  linux/fs/hfs/catalog.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 the functions related to the catalog B-tree.
   9  *
  10  * Cache code shamelessly stolen from
  11  *     linux/fs/inode.c Copyright (C) 1991, 1992  Linus Torvalds
  12  *     re-shamelessly stolen Copyright (C) 1997 Linus Torvalds
  13  */
  14
  15 #include "hfs_fs.h"
  16 #include "btree.h"
  17
  18 /*
  19  * hfs_cat_build_key()
  20  *
  21  * Given the ID of the parent and the name build a search key.
  22  */
  23 void hfs_cat_build_key(btree_key *key, u32 parent, struct qstr *name)
  24 {
  25         key->cat.reserved = 0;
  26         key->cat.ParID = cpu_to_be32(parent);
  27         if (name) {
  28                 hfs_triv2mac(&key->cat.CName, name);
  29                 key->key_len = 6 + key->cat.CName.len;
  30         } else {
  31                 memset(&key->cat.CName, 0, sizeof(struct hfs_name));
  32                 key->key_len = 6;
  33         }
  34 }
  35
  36 static int hfs_cat_build_record(hfs_cat_rec *rec, u32 cnid, struct inode *inode)
  37 {
  38         __be32 mtime = hfs_mtime();
  39
  40         memset(rec, 0, sizeof(*rec));
  41         if (S_ISDIR(inode->i_mode)) {
  42                 rec->type = HFS_CDR_DIR;
  43                 rec->dir.DirID = cpu_to_be32(cnid);
  44                 rec->dir.CrDat = mtime;
  45                 rec->dir.MdDat = mtime;
  46                 rec->dir.BkDat = 0;
  47                 rec->dir.UsrInfo.frView = cpu_to_be16(0xff);
  48                 return sizeof(struct hfs_cat_dir);
  49         } else {
  50                 /* init some fields for the file record */
  51                 rec->type = HFS_CDR_FIL;
  52                 rec->file.Flags = HFS_FIL_USED | HFS_FIL_THD;
  53                 if (!(inode->i_mode & S_IWUSR))
  54                         rec->file.Flags |= HFS_FIL_LOCK;
  55                 rec->file.FlNum = cpu_to_be32(cnid);
  56                 rec->file.CrDat = mtime;
  57                 rec->file.MdDat = mtime;
  58                 rec->file.BkDat = 0;
  59                 rec->file.UsrWds.fdType = HFS_SB(inode->i_sb)->s_type;
  60                 rec->file.UsrWds.fdCreator = HFS_SB(inode->i_sb)->s_creator;
  61                 return sizeof(struct hfs_cat_file);
  62         }
  63 }
  64
  65 static int hfs_cat_build_thread(hfs_cat_rec *rec, int type,
  66                                 u32 parentid, struct qstr *name)
  67 {
  68         rec->type = type;
  69         memset(rec->thread.reserved, 0, sizeof(rec->thread.reserved));
  70         rec->thread.ParID = cpu_to_be32(parentid);
  71         hfs_triv2mac(&rec->thread.CName, name);
  72         return sizeof(struct hfs_cat_thread);
  73 }
  74
  75 /*
  76  * create_entry()
  77  *
  78  * Add a new file or directory to the catalog B-tree and
  79  * return a (struct hfs_cat_entry) for it in '*result'.
  80  */
  81 int hfs_cat_create(u32 cnid, struct inode *dir, struct qstr *str, struct inode *inode)
  82 {
  83         struct hfs_find_data fd;
  84         struct super_block *sb;
  85         union hfs_cat_rec entry;
  86         int entry_size;
  87         int err;
  88
  89         dprint(DBG_CAT_MOD, "create_cat: %s,%u(%d)\n", str->name, cnid, inode->i_nlink);
  90         if (dir->i_size >= HFS_MAX_VALENCE)
  91                 return -ENOSPC;
  92
  93         sb = dir->i_sb;
  94         hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
  95
  96         hfs_cat_build_key(fd.search_key, cnid, NULL);
  97         entry_size = hfs_cat_build_thread(&entry, S_ISDIR(inode->i_mode) ?
  98                         HFS_CDR_THD : HFS_CDR_FTH,
  99                         dir->i_ino, str);
 100         err = hfs_brec_find(&fd);
 101         if (err != -ENOENT) {
 102                 if (!err)
 103                         err = -EEXIST;
 104                 goto err2;
 105         }
 106         err = hfs_brec_insert(&fd, &entry, entry_size);
 107         if (err)
 108                 goto err2;
 109
 110         hfs_cat_build_key(fd.search_key, dir->i_ino, str);
 111         entry_size = hfs_cat_build_record(&entry, cnid, inode);
 112         err = hfs_brec_find(&fd);
 113         if (err != -ENOENT) {
 114                 /* panic? */
 115                 if (!err)
 116                         err = -EEXIST;
 117                 goto err1;
 118         }
 119         err = hfs_brec_insert(&fd, &entry, entry_size);
 120         if (err)
 121                 goto err1;
 122
 123         dir->i_size++;
 124         dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
 125         mark_inode_dirty(dir);
 126         hfs_find_exit(&fd);
 127         return 0;
 128
 129 err1:
 130         hfs_cat_build_key(fd.search_key, cnid, NULL);
 131         if (!hfs_brec_find(&fd))
 132                 hfs_brec_remove(&fd);
 133 err2:
 134         hfs_find_exit(&fd);
 135         return err;
 136 }
 137
 138 /*
 139  * hfs_cat_compare()
 140  *
 141  * Description:
 142  *   This is the comparison function used for the catalog B-tree.  In
 143  *   comparing catalog B-tree entries, the parent id is the most
 144  *   significant field (compared as unsigned ints).  The name field is
 145  *   the least significant (compared in "Macintosh lexical order",
 146  *   see hfs_strcmp() in string.c)
 147  * Input Variable(s):
 148  *   struct hfs_cat_key *key1: pointer to the first key to compare
 149  *   struct hfs_cat_key *key2: pointer to the second key to compare
 150  * Output Variable(s):
 151  *   NONE
 152  * Returns:
 153  *   int: negative if key1<key2, positive if key1>key2, and 0 if key1==key2
 154  * Preconditions:
 155  *   key1 and key2 point to "valid" (struct hfs_cat_key)s.
 156  * Postconditions:
 157  *   This function has no side-effects
 158  */
 159 int hfs_cat_keycmp(const btree_key *key1, const btree_key *key2)
 160 {
 161         int retval;
 162
 163         retval = be32_to_cpu(key1->cat.ParID) - be32_to_cpu(key2->cat.ParID);
 164         if (!retval)
 165                 retval = hfs_strcmp(key1->cat.CName.name, key1->cat.CName.len,
 166                                     key2->cat.CName.name, key2->cat.CName.len);
 167
 168         return retval;
 169 }
 170
 171 /* Try to get a catalog entry for given catalog id */
 172 // move to read_super???
 173 int hfs_cat_find_brec(struct super_block *sb, u32 cnid,
 174                       struct hfs_find_data *fd)
 175 {
 176         hfs_cat_rec rec;
 177         int res, len, type;
 178
 179         hfs_cat_build_key(fd->search_key, cnid, NULL);
 180         res = hfs_brec_read(fd, &rec, sizeof(rec));
 181         if (res)
 182                 return res;
 183
 184         type = rec.type;
 185         if (type != HFS_CDR_THD && type != HFS_CDR_FTH) {
 186                 printk("HFS-fs: Found bad thread record in catalog\n");
 187                 return -EIO;
 188         }
 189
 190         fd->search_key->cat.ParID = rec.thread.ParID;
 191         len = fd->search_key->cat.CName.len = rec.thread.CName.len;
 192         memcpy(fd->search_key->cat.CName.name, rec.thread.CName.name, len);
 193         return hfs_brec_find(fd);
 194 }
 195
 196
 197 /*
 198  * hfs_cat_delete()
 199  *
 200  * Delete the indicated file or directory.
 201  * The associated thread is also removed unless ('with_thread'==0).
 202  */
 203 int hfs_cat_delete(u32 cnid, struct inode *dir, struct qstr *str)
 204 {
 205         struct super_block *sb;
 206         struct hfs_find_data fd;
 207         struct list_head *pos;
 208         int res, type;
 209
 210         dprint(DBG_CAT_MOD, "delete_cat: %s,%u\n", str ? str->name : NULL, cnid);
 211         sb = dir->i_sb;
 212         hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
 213
 214         hfs_cat_build_key(fd.search_key, dir->i_ino, str);
 215         res = hfs_brec_find(&fd);
 216         if (res)
 217                 goto out;
 218
 219         type = hfs_bnode_read_u8(fd.bnode, fd.entryoffset);
 220         if (type == HFS_CDR_FIL) {
 221                 struct hfs_cat_file file;
 222                 hfs_bnode_read(fd.bnode, &file, fd.entryoffset, sizeof(file));
 223                 if (be32_to_cpu(file.FlNum) == cnid) {
 224 #if 0
 225                         hfs_free_fork(sb, &file, HFS_FK_DATA);
 226 #endif
 227                         hfs_free_fork(sb, &file, HFS_FK_RSRC);
 228                 }
 229         }
 230
 231         list_for_each(pos, &HFS_I(dir)->open_dir_list) {
 232                 struct hfs_readdir_data *rd =
 233                         list_entry(pos, struct hfs_readdir_data, list);
 234                 if (fd.tree->keycmp(fd.search_key, (void *)&rd->key) < 0)
 235                         rd->file->f_pos--;
 236         }
 237
 238         res = hfs_brec_remove(&fd);
 239         if (res)
 240                 goto out;
 241
 242         hfs_cat_build_key(fd.search_key, cnid, NULL);
 243         res = hfs_brec_find(&fd);
 244         if (!res) {
 245                 res = hfs_brec_remove(&fd);
 246                 if (res)
 247                         goto out;
 248         }
 249
 250         dir->i_size--;
 251         dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
 252         mark_inode_dirty(dir);
 253         res = 0;
 254 out:
 255         hfs_find_exit(&fd);
 256
 257         return res;
 258 }
 259
 260 /*
 261  * hfs_cat_move()
 262  *
 263  * Rename a file or directory, possibly to a new directory.
 264  * If the destination exists it is removed and a
 265  * (struct hfs_cat_entry) for it is returned in '*result'.
 266  */
 267 int hfs_cat_move(u32 cnid, struct inode *src_dir, struct qstr *src_name,
 268                  struct inode *dst_dir, struct qstr *dst_name)
 269 {
 270         struct super_block *sb;
 271         struct hfs_find_data src_fd, dst_fd;
 272         union hfs_cat_rec entry;
 273         int entry_size, type;
 274         int err;
 275
 276         dprint(DBG_CAT_MOD, "rename_cat: %u - %lu,%s - %lu,%s\n", cnid, src_dir->i_ino, src_name->name,
 277                 dst_dir->i_ino, dst_name->name);
 278         sb = src_dir->i_sb;
 279         hfs_find_init(HFS_SB(sb)->cat_tree, &src_fd);
 280         dst_fd = src_fd;
 281
 282         /* find the old dir entry and read the data */
 283         hfs_cat_build_key(src_fd.search_key, src_dir->i_ino, src_name);
 284         err = hfs_brec_find(&src_fd);
 285         if (err)
 286                 goto out;
 287
 288         hfs_bnode_read(src_fd.bnode, &entry, src_fd.entryoffset,
 289                             src_fd.entrylength);
 290
 291         /* create new dir entry with the data from the old entry */
 292         hfs_cat_build_key(dst_fd.search_key, dst_dir->i_ino, dst_name);
 293         err = hfs_brec_find(&dst_fd);
 294         if (err != -ENOENT) {
 295                 if (!err)
 296                         err = -EEXIST;
 297                 goto out;
 298         }
 299
 300         err = hfs_brec_insert(&dst_fd, &entry, src_fd.entrylength);
 301         if (err)
 302                 goto out;
 303         dst_dir->i_size++;
 304         dst_dir->i_mtime = dst_dir->i_ctime = CURRENT_TIME_SEC;
 305         mark_inode_dirty(dst_dir);
 306
 307         /* finally remove the old entry */
 308         hfs_cat_build_key(src_fd.search_key, src_dir->i_ino, src_name);
 309         err = hfs_brec_find(&src_fd);
 310         if (err)
 311                 goto out;
 312         err = hfs_brec_remove(&src_fd);
 313         if (err)
 314                 goto out;
 315         src_dir->i_size--;
 316         src_dir->i_mtime = src_dir->i_ctime = CURRENT_TIME_SEC;
 317         mark_inode_dirty(src_dir);
 318
 319         type = entry.type;
 320         if (type == HFS_CDR_FIL && !(entry.file.Flags & HFS_FIL_THD))
 321                 goto out;
 322
 323         /* remove old thread entry */
 324         hfs_cat_build_key(src_fd.search_key, cnid, NULL);
 325         err = hfs_brec_find(&src_fd);
 326         if (err)
 327                 goto out;
 328         err = hfs_brec_remove(&src_fd);
 329         if (err)
 330                 goto out;
 331
 332         /* create new thread entry */
 333         hfs_cat_build_key(dst_fd.search_key, cnid, NULL);
 334         entry_size = hfs_cat_build_thread(&entry, type == HFS_CDR_FIL ? HFS_CDR_FTH : HFS_CDR_THD,
 335                                         dst_dir->i_ino, dst_name);
 336         err = hfs_brec_find(&dst_fd);
 337         if (err != -ENOENT) {
 338                 if (!err)
 339                         err = -EEXIST;
 340                 goto out;
 341         }
 342         err = hfs_brec_insert(&dst_fd, &entry, entry_size);
 343 out:
 344         hfs_bnode_put(dst_fd.bnode);
 345         hfs_find_exit(&src_fd);
 346         return err;
 347 }