linux/fs/hfs/catalog.c
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   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(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
  36static 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
  65static 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 */
  82int 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
 130err1:
 131        hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
 132        if (!hfs_brec_find(&fd))
 133                hfs_brec_remove(&fd);
 134err2:
 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 */
 160int 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???
 174int 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 */
 204int 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;
 255out:
 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 */
 268int 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);
 344out:
 345        hfs_bnode_put(dst_fd.bnode);
 346        hfs_find_exit(&src_fd);
 347        return err;
 348}
 349