fs/jffs2/dir.c

   1 /*
   2  * JFFS2 -- Journalling Flash File System, Version 2.
   3  *
   4  * Copyright © 2001-2007 Red Hat, Inc.
   5  * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
   6  *
   7  * Created by David Woodhouse <dwmw2@infradead.org>
   8  *
   9  * For licensing information, see the file 'LICENCE' in this directory.
  10  *
  11  */
  12
  13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15 #include <linux/kernel.h>
  16 #include <linux/slab.h>
  17 #include <linux/fs.h>
  18 #include <linux/crc32.h>
  19 #include <linux/jffs2.h>
  20 #include "jffs2_fs_i.h"
  21 #include "jffs2_fs_sb.h"
  22 #include <linux/time.h>
  23 #include "nodelist.h"
  24
  25 static int jffs2_readdir (struct file *, struct dir_context *);
  26
  27 static int jffs2_create (struct inode *,struct dentry *,umode_t,
  28                          bool);
  29 static struct dentry *jffs2_lookup (struct inode *,struct dentry *,
  30                                     unsigned int);
  31 static int jffs2_link (struct dentry *,struct inode *,struct dentry *);
  32 static int jffs2_unlink (struct inode *,struct dentry *);
  33 static int jffs2_symlink (struct inode *,struct dentry *,const char *);
  34 static int jffs2_mkdir (struct inode *,struct dentry *,umode_t);
  35 static int jffs2_rmdir (struct inode *,struct dentry *);
  36 static int jffs2_mknod (struct inode *,struct dentry *,umode_t,dev_t);
  37 static int jffs2_rename (struct inode *, struct dentry *,
  38                          struct inode *, struct dentry *);
  39
  40 const struct file_operations jffs2_dir_operations =
  41 {
  42         .read =         generic_read_dir,
  43         .iterate =      jffs2_readdir,
  44         .unlocked_ioctl=jffs2_ioctl,
  45         .fsync =        jffs2_fsync,
  46         .llseek =       generic_file_llseek,
  47 };
  48
  49
  50 const struct inode_operations jffs2_dir_inode_operations =
  51 {
  52         .create =       jffs2_create,
  53         .lookup =       jffs2_lookup,
  54         .link =         jffs2_link,
  55         .unlink =       jffs2_unlink,
  56         .symlink =      jffs2_symlink,
  57         .mkdir =        jffs2_mkdir,
  58         .rmdir =        jffs2_rmdir,
  59         .mknod =        jffs2_mknod,
  60         .rename =       jffs2_rename,
  61         .get_acl =      jffs2_get_acl,
  62         .setattr =      jffs2_setattr,
  63         .setxattr =     jffs2_setxattr,
  64         .getxattr =     jffs2_getxattr,
  65         .listxattr =    jffs2_listxattr,
  66         .removexattr =  jffs2_removexattr
  67 };
  68
  69 /***********************************************************************/
  70
  71
  72 /* We keep the dirent list sorted in increasing order of name hash,
  73    and we use the same hash function as the dentries. Makes this
  74    nice and simple
  75 */
  76 static struct dentry *jffs2_lookup(struct inode *dir_i, struct dentry *target,
  77                                    unsigned int flags)
  78 {
  79         struct jffs2_inode_info *dir_f;
  80         struct jffs2_full_dirent *fd = NULL, *fd_list;
  81         uint32_t ino = 0;
  82         struct inode *inode = NULL;
  83
  84         jffs2_dbg(1, "jffs2_lookup()\n");
  85
  86         if (target->d_name.len > JFFS2_MAX_NAME_LEN)
  87                 return ERR_PTR(-ENAMETOOLONG);
  88
  89         dir_f = JFFS2_INODE_INFO(dir_i);
  90
  91         mutex_lock(&dir_f->sem);
  92
  93         /* NB: The 2.2 backport will need to explicitly check for '.' and '..' here */
  94         for (fd_list = dir_f->dents; fd_list && fd_list->nhash <= target->d_name.hash; fd_list = fd_list->next) {
  95                 if (fd_list->nhash == target->d_name.hash &&
  96                     (!fd || fd_list->version > fd->version) &&
  97                     strlen(fd_list->name) == target->d_name.len &&
  98                     !strncmp(fd_list->name, target->d_name.name, target->d_name.len)) {
  99                         fd = fd_list;
 100                 }
 101         }
 102         if (fd)
 103                 ino = fd->ino;
 104         mutex_unlock(&dir_f->sem);
 105         if (ino) {
 106                 inode = jffs2_iget(dir_i->i_sb, ino);
 107                 if (IS_ERR(inode))
 108                         pr_warn("iget() failed for ino #%u\n", ino);
 109         }
 110
 111         return d_splice_alias(inode, target);
 112 }
 113
 114 /***********************************************************************/
 115
 116
 117 static int jffs2_readdir(struct file *file, struct dir_context *ctx)
 118 {
 119         struct inode *inode = file_inode(file);
 120         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
 121         struct jffs2_full_dirent *fd;
 122         unsigned long curofs = 1;
 123
 124         jffs2_dbg(1, "jffs2_readdir() for dir_i #%lu\n", inode->i_ino);
 125
 126         if (!dir_emit_dots(file, ctx))
 127                 return 0;
 128
 129         mutex_lock(&f->sem);
 130         for (fd = f->dents; fd; fd = fd->next) {
 131                 curofs++;
 132                 /* First loop: curofs = 2; pos = 2 */
 133                 if (curofs < ctx->pos) {
 134                         jffs2_dbg(2, "Skipping dirent: \"%s\", ino #%u, type %d, because curofs %ld < offset %ld\n",
 135                                   fd->name, fd->ino, fd->type, curofs, (unsigned long)ctx->pos);
 136                         continue;
 137                 }
 138                 if (!fd->ino) {
 139                         jffs2_dbg(2, "Skipping deletion dirent \"%s\"\n",
 140                                   fd->name);
 141                         ctx->pos++;
 142                         continue;
 143                 }
 144                 jffs2_dbg(2, "Dirent %ld: \"%s\", ino #%u, type %d\n",
 145                           (unsigned long)ctx->pos, fd->name, fd->ino, fd->type);
 146                 if (!dir_emit(ctx, fd->name, strlen(fd->name), fd->ino, fd->type))
 147                         break;
 148                 ctx->pos++;
 149         }
 150         mutex_unlock(&f->sem);
 151         return 0;
 152 }
 153
 154 /***********************************************************************/
 155
 156
 157 static int jffs2_create(struct inode *dir_i, struct dentry *dentry,
 158                         umode_t mode, bool excl)
 159 {
 160         struct jffs2_raw_inode *ri;
 161         struct jffs2_inode_info *f, *dir_f;
 162         struct jffs2_sb_info *c;
 163         struct inode *inode;
 164         int ret;
 165
 166         ri = jffs2_alloc_raw_inode();
 167         if (!ri)
 168                 return -ENOMEM;
 169
 170         c = JFFS2_SB_INFO(dir_i->i_sb);
 171
 172         jffs2_dbg(1, "%s()\n", __func__);
 173
 174         inode = jffs2_new_inode(dir_i, mode, ri);
 175
 176         if (IS_ERR(inode)) {
 177                 jffs2_dbg(1, "jffs2_new_inode() failed\n");
 178                 jffs2_free_raw_inode(ri);
 179                 return PTR_ERR(inode);
 180         }
 181
 182         inode->i_op = &jffs2_file_inode_operations;
 183         inode->i_fop = &jffs2_file_operations;
 184         inode->i_mapping->a_ops = &jffs2_file_address_operations;
 185         inode->i_mapping->nrpages = 0;
 186
 187         f = JFFS2_INODE_INFO(inode);
 188         dir_f = JFFS2_INODE_INFO(dir_i);
 189
 190         /* jffs2_do_create() will want to lock it, _after_ reserving
 191            space and taking c-alloc_sem. If we keep it locked here,
 192            lockdep gets unhappy (although it's a false positive;
 193            nothing else will be looking at this inode yet so there's
 194            no chance of AB-BA deadlock involving its f->sem). */
 195         mutex_unlock(&f->sem);
 196
 197         ret = jffs2_do_create(c, dir_f, f, ri, &dentry->d_name);
 198         if (ret)
 199                 goto fail;
 200
 201         dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(ri->ctime));
 202
 203         jffs2_free_raw_inode(ri);
 204
 205         jffs2_dbg(1, "%s(): Created ino #%lu with mode %o, nlink %d(%d). nrpages %ld\n",
 206                   __func__, inode->i_ino, inode->i_mode, inode->i_nlink,
 207                   f->inocache->pino_nlink, inode->i_mapping->nrpages);
 208
 209         unlock_new_inode(inode);
 210         d_instantiate(dentry, inode);
 211         return 0;
 212
 213  fail:
 214         iget_failed(inode);
 215         jffs2_free_raw_inode(ri);
 216         return ret;
 217 }
 218
 219 /***********************************************************************/
 220
 221
 222 static int jffs2_unlink(struct inode *dir_i, struct dentry *dentry)
 223 {
 224         struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
 225         struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
 226         struct jffs2_inode_info *dead_f = JFFS2_INODE_INFO(dentry->d_inode);
 227         int ret;
 228         uint32_t now = get_seconds();
 229
 230         ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name,
 231                               dentry->d_name.len, dead_f, now);
 232         if (dead_f->inocache)
 233                 set_nlink(dentry->d_inode, dead_f->inocache->pino_nlink);
 234         if (!ret)
 235                 dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
 236         return ret;
 237 }
 238 /***********************************************************************/
 239
 240
 241 static int jffs2_link (struct dentry *old_dentry, struct inode *dir_i, struct dentry *dentry)
 242 {
 243         struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dentry->d_inode->i_sb);
 244         struct jffs2_inode_info *f = JFFS2_INODE_INFO(old_dentry->d_inode);
 245         struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
 246         int ret;
 247         uint8_t type;
 248         uint32_t now;
 249
 250         /* Don't let people make hard links to bad inodes. */
 251         if (!f->inocache)
 252                 return -EIO;
 253
 254         if (S_ISDIR(old_dentry->d_inode->i_mode))
 255                 return -EPERM;
 256
 257         /* XXX: This is ugly */
 258         type = (old_dentry->d_inode->i_mode & S_IFMT) >> 12;
 259         if (!type) type = DT_REG;
 260
 261         now = get_seconds();
 262         ret = jffs2_do_link(c, dir_f, f->inocache->ino, type, dentry->d_name.name, dentry->d_name.len, now);
 263
 264         if (!ret) {
 265                 mutex_lock(&f->sem);
 266                 set_nlink(old_dentry->d_inode, ++f->inocache->pino_nlink);
 267                 mutex_unlock(&f->sem);
 268                 d_instantiate(dentry, old_dentry->d_inode);
 269                 dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
 270                 ihold(old_dentry->d_inode);
 271         }
 272         return ret;
 273 }
 274
 275 /***********************************************************************/
 276
 277 static int jffs2_symlink (struct inode *dir_i, struct dentry *dentry, const char *target)
 278 {
 279         struct jffs2_inode_info *f, *dir_f;
 280         struct jffs2_sb_info *c;
 281         struct inode *inode;
 282         struct jffs2_raw_inode *ri;
 283         struct jffs2_raw_dirent *rd;
 284         struct jffs2_full_dnode *fn;
 285         struct jffs2_full_dirent *fd;
 286         int namelen;
 287         uint32_t alloclen;
 288         int ret, targetlen = strlen(target);
 289
 290         /* FIXME: If you care. We'd need to use frags for the target
 291            if it grows much more than this */
 292         if (targetlen > 254)
 293                 return -ENAMETOOLONG;
 294
 295         ri = jffs2_alloc_raw_inode();
 296
 297         if (!ri)
 298                 return -ENOMEM;
 299
 300         c = JFFS2_SB_INFO(dir_i->i_sb);
 301
 302         /* Try to reserve enough space for both node and dirent.
 303          * Just the node will do for now, though
 304          */
 305         namelen = dentry->d_name.len;
 306         ret = jffs2_reserve_space(c, sizeof(*ri) + targetlen, &alloclen,
 307                                   ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
 308
 309         if (ret) {
 310                 jffs2_free_raw_inode(ri);
 311                 return ret;
 312         }
 313
 314         inode = jffs2_new_inode(dir_i, S_IFLNK | S_IRWXUGO, ri);
 315
 316         if (IS_ERR(inode)) {
 317                 jffs2_free_raw_inode(ri);
 318                 jffs2_complete_reservation(c);
 319                 return PTR_ERR(inode);
 320         }
 321
 322         inode->i_op = &jffs2_symlink_inode_operations;
 323
 324         f = JFFS2_INODE_INFO(inode);
 325
 326         inode->i_size = targetlen;
 327         ri->isize = ri->dsize = ri->csize = cpu_to_je32(inode->i_size);
 328         ri->totlen = cpu_to_je32(sizeof(*ri) + inode->i_size);
 329         ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
 330
 331         ri->compr = JFFS2_COMPR_NONE;
 332         ri->data_crc = cpu_to_je32(crc32(0, target, targetlen));
 333         ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
 334
 335         fn = jffs2_write_dnode(c, f, ri, target, targetlen, ALLOC_NORMAL);
 336
 337         jffs2_free_raw_inode(ri);
 338
 339         if (IS_ERR(fn)) {
 340                 /* Eeek. Wave bye bye */
 341                 mutex_unlock(&f->sem);
 342                 jffs2_complete_reservation(c);
 343                 ret = PTR_ERR(fn);
 344                 goto fail;
 345         }
 346
 347         /* We use f->target field to store the target path. */
 348         f->target = kmemdup(target, targetlen + 1, GFP_KERNEL);
 349         if (!f->target) {
 350                 pr_warn("Can't allocate %d bytes of memory\n", targetlen + 1);
 351                 mutex_unlock(&f->sem);
 352                 jffs2_complete_reservation(c);
 353                 ret = -ENOMEM;
 354                 goto fail;
 355         }
 356
 357         jffs2_dbg(1, "%s(): symlink's target '%s' cached\n",
 358                   __func__, (char *)f->target);
 359
 360         /* No data here. Only a metadata node, which will be
 361            obsoleted by the first data write
 362         */
 363         f->metadata = fn;
 364         mutex_unlock(&f->sem);
 365
 366         jffs2_complete_reservation(c);
 367
 368         ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
 369         if (ret)
 370                 goto fail;
 371
 372         ret = jffs2_init_acl_post(inode);
 373         if (ret)
 374                 goto fail;
 375
 376         ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
 377                                   ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 378         if (ret)
 379                 goto fail;
 380
 381         rd = jffs2_alloc_raw_dirent();
 382         if (!rd) {
 383                 /* Argh. Now we treat it like a normal delete */
 384                 jffs2_complete_reservation(c);
 385                 ret = -ENOMEM;
 386                 goto fail;
 387         }
 388
 389         dir_f = JFFS2_INODE_INFO(dir_i);
 390         mutex_lock(&dir_f->sem);
 391
 392         rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
 393         rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
 394         rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
 395         rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
 396
 397         rd->pino = cpu_to_je32(dir_i->i_ino);
 398         rd->version = cpu_to_je32(++dir_f->highest_version);
 399         rd->ino = cpu_to_je32(inode->i_ino);
 400         rd->mctime = cpu_to_je32(get_seconds());
 401         rd->nsize = namelen;
 402         rd->type = DT_LNK;
 403         rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
 404         rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
 405
 406         fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
 407
 408         if (IS_ERR(fd)) {
 409                 /* dirent failed to write. Delete the inode normally
 410                    as if it were the final unlink() */
 411                 jffs2_complete_reservation(c);
 412                 jffs2_free_raw_dirent(rd);
 413                 mutex_unlock(&dir_f->sem);
 414                 ret = PTR_ERR(fd);
 415                 goto fail;
 416         }
 417
 418         dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
 419
 420         jffs2_free_raw_dirent(rd);
 421
 422         /* Link the fd into the inode's list, obsoleting an old
 423            one if necessary. */
 424         jffs2_add_fd_to_list(c, fd, &dir_f->dents);
 425
 426         mutex_unlock(&dir_f->sem);
 427         jffs2_complete_reservation(c);
 428
 429         unlock_new_inode(inode);
 430         d_instantiate(dentry, inode);
 431         return 0;
 432
 433  fail:
 434         iget_failed(inode);
 435         return ret;
 436 }
 437
 438
 439 static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, umode_t mode)
 440 {
 441         struct jffs2_inode_info *f, *dir_f;
 442         struct jffs2_sb_info *c;
 443         struct inode *inode;
 444         struct jffs2_raw_inode *ri;
 445         struct jffs2_raw_dirent *rd;
 446         struct jffs2_full_dnode *fn;
 447         struct jffs2_full_dirent *fd;
 448         int namelen;
 449         uint32_t alloclen;
 450         int ret;
 451
 452         mode |= S_IFDIR;
 453
 454         ri = jffs2_alloc_raw_inode();
 455         if (!ri)
 456                 return -ENOMEM;
 457
 458         c = JFFS2_SB_INFO(dir_i->i_sb);
 459
 460         /* Try to reserve enough space for both node and dirent.
 461          * Just the node will do for now, though
 462          */
 463         namelen = dentry->d_name.len;
 464         ret = jffs2_reserve_space(c, sizeof(*ri), &alloclen, ALLOC_NORMAL,
 465                                   JFFS2_SUMMARY_INODE_SIZE);
 466
 467         if (ret) {
 468                 jffs2_free_raw_inode(ri);
 469                 return ret;
 470         }
 471
 472         inode = jffs2_new_inode(dir_i, mode, ri);
 473
 474         if (IS_ERR(inode)) {
 475                 jffs2_free_raw_inode(ri);
 476                 jffs2_complete_reservation(c);
 477                 return PTR_ERR(inode);
 478         }
 479
 480         inode->i_op = &jffs2_dir_inode_operations;
 481         inode->i_fop = &jffs2_dir_operations;
 482
 483         f = JFFS2_INODE_INFO(inode);
 484
 485         /* Directories get nlink 2 at start */
 486         set_nlink(inode, 2);
 487         /* but ic->pino_nlink is the parent ino# */
 488         f->inocache->pino_nlink = dir_i->i_ino;
 489
 490         ri->data_crc = cpu_to_je32(0);
 491         ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
 492
 493         fn = jffs2_write_dnode(c, f, ri, NULL, 0, ALLOC_NORMAL);
 494
 495         jffs2_free_raw_inode(ri);
 496
 497         if (IS_ERR(fn)) {
 498                 /* Eeek. Wave bye bye */
 499                 mutex_unlock(&f->sem);
 500                 jffs2_complete_reservation(c);
 501                 ret = PTR_ERR(fn);
 502                 goto fail;
 503         }
 504         /* No data here. Only a metadata node, which will be
 505            obsoleted by the first data write
 506         */
 507         f->metadata = fn;
 508         mutex_unlock(&f->sem);
 509
 510         jffs2_complete_reservation(c);
 511
 512         ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
 513         if (ret)
 514                 goto fail;
 515
 516         ret = jffs2_init_acl_post(inode);
 517         if (ret)
 518                 goto fail;
 519
 520         ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
 521                                   ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 522         if (ret)
 523                 goto fail;
 524
 525         rd = jffs2_alloc_raw_dirent();
 526         if (!rd) {
 527                 /* Argh. Now we treat it like a normal delete */
 528                 jffs2_complete_reservation(c);
 529                 ret = -ENOMEM;
 530                 goto fail;
 531         }
 532
 533         dir_f = JFFS2_INODE_INFO(dir_i);
 534         mutex_lock(&dir_f->sem);
 535
 536         rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
 537         rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
 538         rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
 539         rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
 540
 541         rd->pino = cpu_to_je32(dir_i->i_ino);
 542         rd->version = cpu_to_je32(++dir_f->highest_version);
 543         rd->ino = cpu_to_je32(inode->i_ino);
 544         rd->mctime = cpu_to_je32(get_seconds());
 545         rd->nsize = namelen;
 546         rd->type = DT_DIR;
 547         rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
 548         rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
 549
 550         fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
 551
 552         if (IS_ERR(fd)) {
 553                 /* dirent failed to write. Delete the inode normally
 554                    as if it were the final unlink() */
 555                 jffs2_complete_reservation(c);
 556                 jffs2_free_raw_dirent(rd);
 557                 mutex_unlock(&dir_f->sem);
 558                 ret = PTR_ERR(fd);
 559                 goto fail;
 560         }
 561
 562         dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
 563         inc_nlink(dir_i);
 564
 565         jffs2_free_raw_dirent(rd);
 566
 567         /* Link the fd into the inode's list, obsoleting an old
 568            one if necessary. */
 569         jffs2_add_fd_to_list(c, fd, &dir_f->dents);
 570
 571         mutex_unlock(&dir_f->sem);
 572         jffs2_complete_reservation(c);
 573
 574         unlock_new_inode(inode);
 575         d_instantiate(dentry, inode);
 576         return 0;
 577
 578  fail:
 579         iget_failed(inode);
 580         return ret;
 581 }
 582
 583 static int jffs2_rmdir (struct inode *dir_i, struct dentry *dentry)
 584 {
 585         struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
 586         struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
 587         struct jffs2_inode_info *f = JFFS2_INODE_INFO(dentry->d_inode);
 588         struct jffs2_full_dirent *fd;
 589         int ret;
 590         uint32_t now = get_seconds();
 591
 592         for (fd = f->dents ; fd; fd = fd->next) {
 593                 if (fd->ino)
 594                         return -ENOTEMPTY;
 595         }
 596
 597         ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name,
 598                               dentry->d_name.len, f, now);
 599         if (!ret) {
 600                 dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
 601                 clear_nlink(dentry->d_inode);
 602                 drop_nlink(dir_i);
 603         }
 604         return ret;
 605 }
 606
 607 static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, umode_t mode, dev_t rdev)
 608 {
 609         struct jffs2_inode_info *f, *dir_f;
 610         struct jffs2_sb_info *c;
 611         struct inode *inode;
 612         struct jffs2_raw_inode *ri;
 613         struct jffs2_raw_dirent *rd;
 614         struct jffs2_full_dnode *fn;
 615         struct jffs2_full_dirent *fd;
 616         int namelen;
 617         union jffs2_device_node dev;
 618         int devlen = 0;
 619         uint32_t alloclen;
 620         int ret;
 621
 622         if (!new_valid_dev(rdev))
 623                 return -EINVAL;
 624
 625         ri = jffs2_alloc_raw_inode();
 626         if (!ri)
 627                 return -ENOMEM;
 628
 629         c = JFFS2_SB_INFO(dir_i->i_sb);
 630
 631         if (S_ISBLK(mode) || S_ISCHR(mode))
 632                 devlen = jffs2_encode_dev(&dev, rdev);
 633
 634         /* Try to reserve enough space for both node and dirent.
 635          * Just the node will do for now, though
 636          */
 637         namelen = dentry->d_name.len;
 638         ret = jffs2_reserve_space(c, sizeof(*ri) + devlen, &alloclen,
 639                                   ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
 640
 641         if (ret) {
 642                 jffs2_free_raw_inode(ri);
 643                 return ret;
 644         }
 645
 646         inode = jffs2_new_inode(dir_i, mode, ri);
 647
 648         if (IS_ERR(inode)) {
 649                 jffs2_free_raw_inode(ri);
 650                 jffs2_complete_reservation(c);
 651                 return PTR_ERR(inode);
 652         }
 653         inode->i_op = &jffs2_file_inode_operations;
 654         init_special_inode(inode, inode->i_mode, rdev);
 655
 656         f = JFFS2_INODE_INFO(inode);
 657
 658         ri->dsize = ri->csize = cpu_to_je32(devlen);
 659         ri->totlen = cpu_to_je32(sizeof(*ri) + devlen);
 660         ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
 661
 662         ri->compr = JFFS2_COMPR_NONE;
 663         ri->data_crc = cpu_to_je32(crc32(0, &dev, devlen));
 664         ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
 665
 666         fn = jffs2_write_dnode(c, f, ri, (char *)&dev, devlen, ALLOC_NORMAL);
 667
 668         jffs2_free_raw_inode(ri);
 669
 670         if (IS_ERR(fn)) {
 671                 /* Eeek. Wave bye bye */
 672                 mutex_unlock(&f->sem);
 673                 jffs2_complete_reservation(c);
 674                 ret = PTR_ERR(fn);
 675                 goto fail;
 676         }
 677         /* No data here. Only a metadata node, which will be
 678            obsoleted by the first data write
 679         */
 680         f->metadata = fn;
 681         mutex_unlock(&f->sem);
 682
 683         jffs2_complete_reservation(c);
 684
 685         ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
 686         if (ret)
 687                 goto fail;
 688
 689         ret = jffs2_init_acl_post(inode);
 690         if (ret)
 691                 goto fail;
 692
 693         ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
 694                                   ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 695         if (ret)
 696                 goto fail;
 697
 698         rd = jffs2_alloc_raw_dirent();
 699         if (!rd) {
 700                 /* Argh. Now we treat it like a normal delete */
 701                 jffs2_complete_reservation(c);
 702                 ret = -ENOMEM;
 703                 goto fail;
 704         }
 705
 706         dir_f = JFFS2_INODE_INFO(dir_i);
 707         mutex_lock(&dir_f->sem);
 708
 709         rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
 710         rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
 711         rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
 712         rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
 713
 714         rd->pino = cpu_to_je32(dir_i->i_ino);
 715         rd->version = cpu_to_je32(++dir_f->highest_version);
 716         rd->ino = cpu_to_je32(inode->i_ino);
 717         rd->mctime = cpu_to_je32(get_seconds());
 718         rd->nsize = namelen;
 719
 720         /* XXX: This is ugly. */
 721         rd->type = (mode & S_IFMT) >> 12;
 722
 723         rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
 724         rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
 725
 726         fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
 727
 728         if (IS_ERR(fd)) {
 729                 /* dirent failed to write. Delete the inode normally
 730                    as if it were the final unlink() */
 731                 jffs2_complete_reservation(c);
 732                 jffs2_free_raw_dirent(rd);
 733                 mutex_unlock(&dir_f->sem);
 734                 ret = PTR_ERR(fd);
 735                 goto fail;
 736         }
 737
 738         dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
 739
 740         jffs2_free_raw_dirent(rd);
 741
 742         /* Link the fd into the inode's list, obsoleting an old
 743            one if necessary. */
 744         jffs2_add_fd_to_list(c, fd, &dir_f->dents);
 745
 746         mutex_unlock(&dir_f->sem);
 747         jffs2_complete_reservation(c);
 748
 749         unlock_new_inode(inode);
 750         d_instantiate(dentry, inode);
 751         return 0;
 752
 753  fail:
 754         iget_failed(inode);
 755         return ret;
 756 }
 757
 758 static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry,
 759                          struct inode *new_dir_i, struct dentry *new_dentry)
 760 {
 761         int ret;
 762         struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dir_i->i_sb);
 763         struct jffs2_inode_info *victim_f = NULL;
 764         uint8_t type;
 765         uint32_t now;
 766
 767         /* The VFS will check for us and prevent trying to rename a
 768          * file over a directory and vice versa, but if it's a directory,
 769          * the VFS can't check whether the victim is empty. The filesystem
 770          * needs to do that for itself.
 771          */
 772         if (new_dentry->d_inode) {
 773                 victim_f = JFFS2_INODE_INFO(new_dentry->d_inode);
 774                 if (S_ISDIR(new_dentry->d_inode->i_mode)) {
 775                         struct jffs2_full_dirent *fd;
 776
 777                         mutex_lock(&victim_f->sem);
 778                         for (fd = victim_f->dents; fd; fd = fd->next) {
 779                                 if (fd->ino) {
 780                                         mutex_unlock(&victim_f->sem);
 781                                         return -ENOTEMPTY;
 782                                 }
 783                         }
 784                         mutex_unlock(&victim_f->sem);
 785                 }
 786         }
 787
 788         /* XXX: We probably ought to alloc enough space for
 789            both nodes at the same time. Writing the new link,
 790            then getting -ENOSPC, is quite bad :)
 791         */
 792
 793         /* Make a hard link */
 794
 795         /* XXX: This is ugly */
 796         type = (old_dentry->d_inode->i_mode & S_IFMT) >> 12;
 797         if (!type) type = DT_REG;
 798
 799         now = get_seconds();
 800         ret = jffs2_do_link(c, JFFS2_INODE_INFO(new_dir_i),
 801                             old_dentry->d_inode->i_ino, type,
 802                             new_dentry->d_name.name, new_dentry->d_name.len, now);
 803
 804         if (ret)
 805                 return ret;
 806
 807         if (victim_f) {
 808                 /* There was a victim. Kill it off nicely */
 809                 if (S_ISDIR(new_dentry->d_inode->i_mode))
 810                         clear_nlink(new_dentry->d_inode);
 811                 else
 812                         drop_nlink(new_dentry->d_inode);
 813                 /* Don't oops if the victim was a dirent pointing to an
 814                    inode which didn't exist. */
 815                 if (victim_f->inocache) {
 816                         mutex_lock(&victim_f->sem);
 817                         if (S_ISDIR(new_dentry->d_inode->i_mode))
 818                                 victim_f->inocache->pino_nlink = 0;
 819                         else
 820                                 victim_f->inocache->pino_nlink--;
 821                         mutex_unlock(&victim_f->sem);
 822                 }
 823         }
 824
 825         /* If it was a directory we moved, and there was no victim,
 826            increase i_nlink on its new parent */
 827         if (S_ISDIR(old_dentry->d_inode->i_mode) && !victim_f)
 828                 inc_nlink(new_dir_i);
 829
 830         /* Unlink the original */
 831         ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
 832                               old_dentry->d_name.name, old_dentry->d_name.len, NULL, now);
 833
 834         /* We don't touch inode->i_nlink */
 835
 836         if (ret) {
 837                 /* Oh shit. We really ought to make a single node which can do both atomically */
 838                 struct jffs2_inode_info *f = JFFS2_INODE_INFO(old_dentry->d_inode);
 839                 mutex_lock(&f->sem);
 840                 inc_nlink(old_dentry->d_inode);
 841                 if (f->inocache && !S_ISDIR(old_dentry->d_inode->i_mode))
 842                         f->inocache->pino_nlink++;
 843                 mutex_unlock(&f->sem);
 844
 845                 pr_notice("%s(): Link succeeded, unlink failed (err %d). You now have a hard link\n",
 846                           __func__, ret);
 847                 /* Might as well let the VFS know */
 848                 d_instantiate(new_dentry, old_dentry->d_inode);
 849                 ihold(old_dentry->d_inode);
 850                 new_dir_i->i_mtime = new_dir_i->i_ctime = ITIME(now);
 851                 return ret;
 852         }
 853
 854         if (S_ISDIR(old_dentry->d_inode->i_mode))
 855                 drop_nlink(old_dir_i);
 856
 857         new_dir_i->i_mtime = new_dir_i->i_ctime = old_dir_i->i_mtime = old_dir_i->i_ctime = ITIME(now);
 858
 859         return 0;
 860 }
 861