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(struct super_block *sb, 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_asc2mac(sb, &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(struct super_block *sb,
  66                                 hfs_cat_rec *rec, int type,
  67                                 u32 parentid, struct qstr *name)
  68 {
  69         rec->type = type;
  70         memset(rec->thread.reserved, 0, sizeof(rec->thread.reserved));
  71         rec->thread.ParID = cpu_to_be32(parentid);
  72         hfs_asc2mac(sb, &rec->thread.CName, name);
  73         return sizeof(struct hfs_cat_thread);
  74 }
  75
  76 /*
  77  * create_entry()
  78  *
  79  * Add a new file or directory to the catalog B-tree and
  80  * return a (struct hfs_cat_entry) for it in '*result'.
  81  */
  82 int hfs_cat_create(u32 cnid, struct inode *dir, struct qstr *str, struct inode *inode)
  83 {
  84         struct hfs_find_data fd;
  85         struct super_block *sb;
  86         union hfs_cat_rec entry;
  87         int entry_size;
  88         int err;
  89
  90         dprint(DBG_CAT_MOD, "create_cat: %s,%u(%d)\n", str->name, cnid, inode->i_nlink);
  91         if (dir->i_size >= HFS_MAX_VALENCE)
  92                 return -ENOSPC;
  93
  94         sb = dir->i_sb;
  95         hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
  96
  97         hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
  98         entry_size = hfs_cat_build_thread(sb, &entry, S_ISDIR(inode->i_mode) ?
  99                         HFS_CDR_THD : HFS_CDR_FTH,
 100                         dir->i_ino, str);
 101         err = hfs_brec_find(&fd);
 102         if (err != -ENOENT) {
 103                 if (!err)
 104                         err = -EEXIST;
 105                 goto err2;
 106         }
 107         err = hfs_brec_insert(&fd, &entry, entry_size);
 108         if (err)
 109                 goto err2;
 110
 111         hfs_cat_build_key(sb, fd.search_key, dir->i_ino, str);
 112         entry_size = hfs_cat_build_record(&entry, cnid, inode);
 113         err = hfs_brec_find(&fd);
 114         if (err != -ENOENT) {
 115                 /* panic? */
 116                 if (!err)
 117                         err = -EEXIST;
 118                 goto err1;
 119         }
 120         err = hfs_brec_insert(&fd, &entry, entry_size);
 121         if (err)
 122                 goto err1;
 123
 124         dir->i_size++;
 125         dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
 126         mark_inode_dirty(dir);
 127         hfs_find_exit(&fd);
 128         return 0;
 129
 130 err1:
 131         hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
 132         if (!hfs_brec_find(&fd))
 133                 hfs_brec_remove(&fd);
 134 err2:
 135         hfs_find_exit(&fd);
 136         return err;
 137 }
 138
 139 /*
 140  * hfs_cat_compare()
 141  *
 142  * Description:
 143  *   This is the comparison function used for the catalog B-tree.  In
 144  *   comparing catalog B-tree entries, the parent id is the most
 145  *   significant field (compared as unsigned ints).  The name field is
 146  *   the least significant (compared in "Macintosh lexical order",
 147  *   see hfs_strcmp() in string.c)
 148  * Input Variable(s):
 149  *   struct hfs_cat_key *key1: pointer to the first key to compare
 150  *   struct hfs_cat_key *key2: pointer to the second key to compare
 151  * Output Variable(s):
 152  *   NONE
 153  * Returns:
 154  *   int: negative if key1<key2, positive if key1>key2, and 0 if key1==key2
 155  * Preconditions:
 156  *   key1 and key2 point to "valid" (struct hfs_cat_key)s.
 157  * Postconditions:
 158  *   This function has no side-effects
 159  */
 160 int hfs_cat_keycmp(const btree_key *key1, const btree_key *key2)
 161 {
 162         int retval;
 163
 164         retval = be32_to_cpu(key1->cat.ParID) - be32_to_cpu(key2->cat.ParID);
 165         if (!retval)
 166                 retval = hfs_strcmp(key1->cat.CName.name, key1->cat.CName.len,
 167                                     key2->cat.CName.name, key2->cat.CName.len);
 168
 169         return retval;
 170 }
 171
 172 /* Try to get a catalog entry for given catalog id */
 173 // move to read_super???
 174 int hfs_cat_find_brec(struct super_block *sb, u32 cnid,
 175                       struct hfs_find_data *fd)
 176 {
 177         hfs_cat_rec rec;
 178         int res, len, type;
 179
 180         hfs_cat_build_key(sb, fd->search_key, cnid, NULL);
 181         res = hfs_brec_read(fd, &rec, sizeof(rec));
 182         if (res)
 183                 return res;
 184
 185         type = rec.type;
 186         if (type != HFS_CDR_THD && type != HFS_CDR_FTH) {
 187                 printk(KERN_ERR "hfs: found bad thread record in catalog\n");
 188                 return -EIO;
 189         }
 190
 191         fd->search_key->cat.ParID = rec.thread.ParID;
 192         len = fd->search_key->cat.CName.len = rec.thread.CName.len;
 193         memcpy(fd->search_key->cat.CName.name, rec.thread.CName.name, len);
 194         return hfs_brec_find(fd);
 195 }
 196
 197
 198 /*
 199  * hfs_cat_delete()
 200  *
 201  * Delete the indicated file or directory.
 202  * The associated thread is also removed unless ('with_thread'==0).
 203  */
 204 int hfs_cat_delete(u32 cnid, struct inode *dir, struct qstr *str)
 205 {
 206         struct super_block *sb;
 207         struct hfs_find_data fd;
 208         struct list_head *pos;
 209         int res, type;
 210
 211         dprint(DBG_CAT_MOD, "delete_cat: %s,%u\n", str ? str->name : NULL, cnid);
 212         sb = dir->i_sb;
 213         hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
 214
 215         hfs_cat_build_key(sb, fd.search_key, dir->i_ino, str);
 216         res = hfs_brec_find(&fd);
 217         if (res)
 218                 goto out;
 219
 220         type = hfs_bnode_read_u8(fd.bnode, fd.entryoffset);
 221         if (type == HFS_CDR_FIL) {
 222                 struct hfs_cat_file file;
 223                 hfs_bnode_read(fd.bnode, &file, fd.entryoffset, sizeof(file));
 224                 if (be32_to_cpu(file.FlNum) == cnid) {
 225 #if 0
 226                         hfs_free_fork(sb, &file, HFS_FK_DATA);
 227 #endif
 228                         hfs_free_fork(sb, &file, HFS_FK_RSRC);
 229                 }
 230         }
 231
 232         list_for_each(pos, &HFS_I(dir)->open_dir_list) {
 233                 struct hfs_readdir_data *rd =
 234                         list_entry(pos, struct hfs_readdir_data, list);
 235                 if (fd.tree->keycmp(fd.search_key, (void *)&rd->key) < 0)
 236                         rd->file->f_pos--;
 237         }
 238
 239         res = hfs_brec_remove(&fd);
 240         if (res)
 241                 goto out;
 242
 243         hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
 244         res = hfs_brec_find(&fd);
 245         if (!res) {
 246                 res = hfs_brec_remove(&fd);
 247                 if (res)
 248                         goto out;
 249         }
 250
 251         dir->i_size--;
 252         dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
 253         mark_inode_dirty(dir);
 254         res = 0;
 255 out:
 256         hfs_find_exit(&fd);
 257
 258         return res;
 259 }
 260
 261 /*
 262  * hfs_cat_move()
 263  *
 264  * Rename a file or directory, possibly to a new directory.
 265  * If the destination exists it is removed and a
 266  * (struct hfs_cat_entry) for it is returned in '*result'.
 267  */
 268 int hfs_cat_move(u32 cnid, struct inode *src_dir, struct qstr *src_name,
 269                  struct inode *dst_dir, struct qstr *dst_name)
 270 {
 271         struct super_block *sb;
 272         struct hfs_find_data src_fd, dst_fd;
 273         union hfs_cat_rec entry;
 274         int entry_size, type;
 275         int err;
 276
 277         dprint(DBG_CAT_MOD, "rename_cat: %u - %lu,%s - %lu,%s\n", cnid, src_dir->i_ino, src_name->name,
 278                 dst_dir->i_ino, dst_name->name);
 279         sb = src_dir->i_sb;
 280         hfs_find_init(HFS_SB(sb)->cat_tree, &src_fd);
 281         dst_fd = src_fd;
 282
 283         /* find the old dir entry and read the data */
 284         hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);
 285         err = hfs_brec_find(&src_fd);
 286         if (err)
 287                 goto out;
 288
 289         hfs_bnode_read(src_fd.bnode, &entry, src_fd.entryoffset,
 290                             src_fd.entrylength);
 291
 292         /* create new dir entry with the data from the old entry */
 293         hfs_cat_build_key(sb, dst_fd.search_key, dst_dir->i_ino, dst_name);
 294         err = hfs_brec_find(&dst_fd);
 295         if (err != -ENOENT) {
 296                 if (!err)
 297                         err = -EEXIST;
 298                 goto out;
 299         }
 300
 301         err = hfs_brec_insert(&dst_fd, &entry, src_fd.entrylength);
 302         if (err)
 303                 goto out;
 304         dst_dir->i_size++;
 305         dst_dir->i_mtime = dst_dir->i_ctime = CURRENT_TIME_SEC;
 306         mark_inode_dirty(dst_dir);
 307
 308         /* finally remove the old entry */
 309         hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);
 310         err = hfs_brec_find(&src_fd);
 311         if (err)
 312                 goto out;
 313         err = hfs_brec_remove(&src_fd);
 314         if (err)
 315                 goto out;
 316         src_dir->i_size--;
 317         src_dir->i_mtime = src_dir->i_ctime = CURRENT_TIME_SEC;
 318         mark_inode_dirty(src_dir);
 319
 320         type = entry.type;
 321         if (type == HFS_CDR_FIL && !(entry.file.Flags & HFS_FIL_THD))
 322                 goto out;
 323
 324         /* remove old thread entry */
 325         hfs_cat_build_key(sb, src_fd.search_key, cnid, NULL);
 326         err = hfs_brec_find(&src_fd);
 327         if (err)
 328                 goto out;
 329         err = hfs_brec_remove(&src_fd);
 330         if (err)
 331                 goto out;
 332
 333         /* create new thread entry */
 334         hfs_cat_build_key(sb, dst_fd.search_key, cnid, NULL);
 335         entry_size = hfs_cat_build_thread(sb, &entry, type == HFS_CDR_FIL ? HFS_CDR_FTH : HFS_CDR_THD,
 336                                         dst_dir->i_ino, dst_name);
 337         err = hfs_brec_find(&dst_fd);
 338         if (err != -ENOENT) {
 339                 if (!err)
 340                         err = -EEXIST;
 341                 goto out;
 342         }
 343         err = hfs_brec_insert(&dst_fd, &entry, entry_size);
 344 out:
 345         hfs_bnode_put(dst_fd.bnode);
 346         hfs_find_exit(&src_fd);
 347         return err;
 348 }