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, const 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, const 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, const 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         hfs_dbg(CAT_MOD, "create_cat: %s,%u(%d)\n",
  91                 str->name, cnid, inode->i_nlink);
  92         if (dir->i_size >= HFS_MAX_VALENCE)
  93                 return -ENOSPC;
  94
  95         sb = dir->i_sb;
  96         err = hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
  97         if (err)
  98                 return err;
  99
 100         hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
 101         entry_size = hfs_cat_build_thread(sb, &entry, S_ISDIR(inode->i_mode) ?
 102                         HFS_CDR_THD : HFS_CDR_FTH,
 103                         dir->i_ino, str);
 104         err = hfs_brec_find(&fd);
 105         if (err != -ENOENT) {
 106                 if (!err)
 107                         err = -EEXIST;
 108                 goto err2;
 109         }
 110         err = hfs_brec_insert(&fd, &entry, entry_size);
 111         if (err)
 112                 goto err2;
 113
 114         hfs_cat_build_key(sb, fd.search_key, dir->i_ino, str);
 115         entry_size = hfs_cat_build_record(&entry, cnid, inode);
 116         err = hfs_brec_find(&fd);
 117         if (err != -ENOENT) {
 118                 /* panic? */
 119                 if (!err)
 120                         err = -EEXIST;
 121                 goto err1;
 122         }
 123         err = hfs_brec_insert(&fd, &entry, entry_size);
 124         if (err)
 125                 goto err1;
 126
 127         dir->i_size++;
 128         dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
 129         mark_inode_dirty(dir);
 130         hfs_find_exit(&fd);
 131         return 0;
 132
 133 err1:
 134         hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
 135         if (!hfs_brec_find(&fd))
 136                 hfs_brec_remove(&fd);
 137 err2:
 138         hfs_find_exit(&fd);
 139         return err;
 140 }
 141
 142 /*
 143  * hfs_cat_compare()
 144  *
 145  * Description:
 146  *   This is the comparison function used for the catalog B-tree.  In
 147  *   comparing catalog B-tree entries, the parent id is the most
 148  *   significant field (compared as unsigned ints).  The name field is
 149  *   the least significant (compared in "Macintosh lexical order",
 150  *   see hfs_strcmp() in string.c)
 151  * Input Variable(s):
 152  *   struct hfs_cat_key *key1: pointer to the first key to compare
 153  *   struct hfs_cat_key *key2: pointer to the second key to compare
 154  * Output Variable(s):
 155  *   NONE
 156  * Returns:
 157  *   int: negative if key1<key2, positive if key1>key2, and 0 if key1==key2
 158  * Preconditions:
 159  *   key1 and key2 point to "valid" (struct hfs_cat_key)s.
 160  * Postconditions:
 161  *   This function has no side-effects
 162  */
 163 int hfs_cat_keycmp(const btree_key *key1, const btree_key *key2)
 164 {
 165         __be32 k1p, k2p;
 166
 167         k1p = key1->cat.ParID;
 168         k2p = key2->cat.ParID;
 169
 170         if (k1p != k2p)
 171                 return be32_to_cpu(k1p) < be32_to_cpu(k2p) ? -1 : 1;
 172
 173         return hfs_strcmp(key1->cat.CName.name, key1->cat.CName.len,
 174                           key2->cat.CName.name, key2->cat.CName.len);
 175 }
 176
 177 /* Try to get a catalog entry for given catalog id */
 178 // move to read_super???
 179 int hfs_cat_find_brec(struct super_block *sb, u32 cnid,
 180                       struct hfs_find_data *fd)
 181 {
 182         hfs_cat_rec rec;
 183         int res, len, type;
 184
 185         hfs_cat_build_key(sb, fd->search_key, cnid, NULL);
 186         res = hfs_brec_read(fd, &rec, sizeof(rec));
 187         if (res)
 188                 return res;
 189
 190         type = rec.type;
 191         if (type != HFS_CDR_THD && type != HFS_CDR_FTH) {
 192                 pr_err("found bad thread record in catalog\n");
 193                 return -EIO;
 194         }
 195
 196         fd->search_key->cat.ParID = rec.thread.ParID;
 197         len = fd->search_key->cat.CName.len = rec.thread.CName.len;
 198         if (len > HFS_NAMELEN) {
 199                 pr_err("bad catalog namelength\n");
 200                 return -EIO;
 201         }
 202         memcpy(fd->search_key->cat.CName.name, rec.thread.CName.name, len);
 203         return hfs_brec_find(fd);
 204 }
 205
 206
 207 /*
 208  * hfs_cat_delete()
 209  *
 210  * Delete the indicated file or directory.
 211  * The associated thread is also removed unless ('with_thread'==0).
 212  */
 213 int hfs_cat_delete(u32 cnid, struct inode *dir, const struct qstr *str)
 214 {
 215         struct super_block *sb;
 216         struct hfs_find_data fd;
 217         struct hfs_readdir_data *rd;
 218         int res, type;
 219
 220         hfs_dbg(CAT_MOD, "delete_cat: %s,%u\n", str ? str->name : NULL, cnid);
 221         sb = dir->i_sb;
 222         res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
 223         if (res)
 224                 return res;
 225
 226         hfs_cat_build_key(sb, fd.search_key, dir->i_ino, str);
 227         res = hfs_brec_find(&fd);
 228         if (res)
 229                 goto out;
 230
 231         type = hfs_bnode_read_u8(fd.bnode, fd.entryoffset);
 232         if (type == HFS_CDR_FIL) {
 233                 struct hfs_cat_file file;
 234                 hfs_bnode_read(fd.bnode, &file, fd.entryoffset, sizeof(file));
 235                 if (be32_to_cpu(file.FlNum) == cnid) {
 236 #if 0
 237                         hfs_free_fork(sb, &file, HFS_FK_DATA);
 238 #endif
 239                         hfs_free_fork(sb, &file, HFS_FK_RSRC);
 240                 }
 241         }
 242
 243         /* we only need to take spinlock for exclusion with ->release() */
 244         spin_lock(&HFS_I(dir)->open_dir_lock);
 245         list_for_each_entry(rd, &HFS_I(dir)->open_dir_list, list) {
 246                 if (fd.tree->keycmp(fd.search_key, (void *)&rd->key) < 0)
 247                         rd->file->f_pos--;
 248         }
 249         spin_unlock(&HFS_I(dir)->open_dir_lock);
 250
 251         res = hfs_brec_remove(&fd);
 252         if (res)
 253                 goto out;
 254
 255         hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
 256         res = hfs_brec_find(&fd);
 257         if (!res) {
 258                 res = hfs_brec_remove(&fd);
 259                 if (res)
 260                         goto out;
 261         }
 262
 263         dir->i_size--;
 264         dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
 265         mark_inode_dirty(dir);
 266         res = 0;
 267 out:
 268         hfs_find_exit(&fd);
 269
 270         return res;
 271 }
 272
 273 /*
 274  * hfs_cat_move()
 275  *
 276  * Rename a file or directory, possibly to a new directory.
 277  * If the destination exists it is removed and a
 278  * (struct hfs_cat_entry) for it is returned in '*result'.
 279  */
 280 int hfs_cat_move(u32 cnid, struct inode *src_dir, const struct qstr *src_name,
 281                  struct inode *dst_dir, const struct qstr *dst_name)
 282 {
 283         struct super_block *sb;
 284         struct hfs_find_data src_fd, dst_fd;
 285         union hfs_cat_rec entry;
 286         int entry_size, type;
 287         int err;
 288
 289         hfs_dbg(CAT_MOD, "rename_cat: %u - %lu,%s - %lu,%s\n",
 290                 cnid, src_dir->i_ino, src_name->name,
 291                 dst_dir->i_ino, dst_name->name);
 292         sb = src_dir->i_sb;
 293         err = hfs_find_init(HFS_SB(sb)->cat_tree, &src_fd);
 294         if (err)
 295                 return err;
 296         dst_fd = src_fd;
 297
 298         /* find the old dir entry and read the data */
 299         hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);
 300         err = hfs_brec_find(&src_fd);
 301         if (err)
 302                 goto out;
 303         if (src_fd.entrylength > sizeof(entry) || src_fd.entrylength < 0) {
 304                 err = -EIO;
 305                 goto out;
 306         }
 307
 308         hfs_bnode_read(src_fd.bnode, &entry, src_fd.entryoffset,
 309                             src_fd.entrylength);
 310
 311         /* create new dir entry with the data from the old entry */
 312         hfs_cat_build_key(sb, dst_fd.search_key, dst_dir->i_ino, dst_name);
 313         err = hfs_brec_find(&dst_fd);
 314         if (err != -ENOENT) {
 315                 if (!err)
 316                         err = -EEXIST;
 317                 goto out;
 318         }
 319
 320         err = hfs_brec_insert(&dst_fd, &entry, src_fd.entrylength);
 321         if (err)
 322                 goto out;
 323         dst_dir->i_size++;
 324         dst_dir->i_mtime = dst_dir->i_ctime = CURRENT_TIME_SEC;
 325         mark_inode_dirty(dst_dir);
 326
 327         /* finally remove the old entry */
 328         hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);
 329         err = hfs_brec_find(&src_fd);
 330         if (err)
 331                 goto out;
 332         err = hfs_brec_remove(&src_fd);
 333         if (err)
 334                 goto out;
 335         src_dir->i_size--;
 336         src_dir->i_mtime = src_dir->i_ctime = CURRENT_TIME_SEC;
 337         mark_inode_dirty(src_dir);
 338
 339         type = entry.type;
 340         if (type == HFS_CDR_FIL && !(entry.file.Flags & HFS_FIL_THD))
 341                 goto out;
 342
 343         /* remove old thread entry */
 344         hfs_cat_build_key(sb, src_fd.search_key, cnid, NULL);
 345         err = hfs_brec_find(&src_fd);
 346         if (err)
 347                 goto out;
 348         err = hfs_brec_remove(&src_fd);
 349         if (err)
 350                 goto out;
 351
 352         /* create new thread entry */
 353         hfs_cat_build_key(sb, dst_fd.search_key, cnid, NULL);
 354         entry_size = hfs_cat_build_thread(sb, &entry, type == HFS_CDR_FIL ? HFS_CDR_FTH : HFS_CDR_THD,
 355                                         dst_dir->i_ino, dst_name);
 356         err = hfs_brec_find(&dst_fd);
 357         if (err != -ENOENT) {
 358                 if (!err)
 359                         err = -EEXIST;
 360                 goto out;
 361         }
 362         err = hfs_brec_insert(&dst_fd, &entry, entry_size);
 363 out:
 364         hfs_bnode_put(dst_fd.bnode);
 365         hfs_find_exit(&src_fd);
 366         return err;
 367 }