LXR linux-bk/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 */
  23void 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
  36int 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
  65static 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 */
  81int 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
 129err1:
 130        hfs_cat_build_key(fd.search_key, cnid, NULL);
 131        if (!hfs_brec_find(&fd))
 132                hfs_brec_remove(&fd);
 133err2:
 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 */
 159int 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???
 173int 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 */
 203int 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;
 254out:
 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 */
 267int 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);
 343out:
 344        hfs_bnode_put(dst_fd.bnode);
 345        hfs_find_exit(&src_fd);
 346        return err;
 347}
 348