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 *, void *, filldir_t);
  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         .readdir =      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 *filp, void *dirent, filldir_t filldir)
 118 {
 119         struct jffs2_inode_info *f;
 120         struct inode *inode = file_inode(filp);
 121         struct jffs2_full_dirent *fd;
 122         unsigned long offset, curofs;
 123
 124         jffs2_dbg(1, "jffs2_readdir() for dir_i #%lu\n",
 125                   file_inode(filp)->i_ino);
 126
 127         f = JFFS2_INODE_INFO(inode);
 128
 129         offset = filp->f_pos;
 130
 131         if (offset == 0) {
 132                 jffs2_dbg(1, "Dirent 0: \".\", ino #%lu\n", inode->i_ino);
 133                 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
 134                         goto out;
 135                 offset++;
 136         }
 137         if (offset == 1) {
 138                 unsigned long pino = parent_ino(filp->f_path.dentry);
 139                 jffs2_dbg(1, "Dirent 1: \"..\", ino #%lu\n", pino);
 140                 if (filldir(dirent, "..", 2, 1, pino, DT_DIR) < 0)
 141                         goto out;
 142                 offset++;
 143         }
 144
 145         curofs=1;
 146         mutex_lock(&f->sem);
 147         for (fd = f->dents; fd; fd = fd->next) {
 148
 149                 curofs++;
 150                 /* First loop: curofs = 2; offset = 2 */
 151                 if (curofs < offset) {
 152                         jffs2_dbg(2, "Skipping dirent: \"%s\", ino #%u, type %d, because curofs %ld < offset %ld\n",
 153                                   fd->name, fd->ino, fd->type, curofs, offset);
 154                         continue;
 155                 }
 156                 if (!fd->ino) {
 157                         jffs2_dbg(2, "Skipping deletion dirent \"%s\"\n",
 158                                   fd->name);
 159                         offset++;
 160                         continue;
 161                 }
 162                 jffs2_dbg(2, "Dirent %ld: \"%s\", ino #%u, type %d\n",
 163                           offset, fd->name, fd->ino, fd->type);
 164                 if (filldir(dirent, fd->name, strlen(fd->name), offset, fd->ino, fd->type) < 0)
 165                         break;
 166                 offset++;
 167         }
 168         mutex_unlock(&f->sem);
 169  out:
 170         filp->f_pos = offset;
 171         return 0;
 172 }
 173
 174 /***********************************************************************/
 175
 176
 177 static int jffs2_create(struct inode *dir_i, struct dentry *dentry,
 178                         umode_t mode, bool excl)
 179 {
 180         struct jffs2_raw_inode *ri;
 181         struct jffs2_inode_info *f, *dir_f;
 182         struct jffs2_sb_info *c;
 183         struct inode *inode;
 184         int ret;
 185
 186         ri = jffs2_alloc_raw_inode();
 187         if (!ri)
 188                 return -ENOMEM;
 189
 190         c = JFFS2_SB_INFO(dir_i->i_sb);
 191
 192         jffs2_dbg(1, "%s()\n", __func__);
 193
 194         inode = jffs2_new_inode(dir_i, mode, ri);
 195
 196         if (IS_ERR(inode)) {
 197                 jffs2_dbg(1, "jffs2_new_inode() failed\n");
 198                 jffs2_free_raw_inode(ri);
 199                 return PTR_ERR(inode);
 200         }
 201
 202         inode->i_op = &jffs2_file_inode_operations;
 203         inode->i_fop = &jffs2_file_operations;
 204         inode->i_mapping->a_ops = &jffs2_file_address_operations;
 205         inode->i_mapping->nrpages = 0;
 206
 207         f = JFFS2_INODE_INFO(inode);
 208         dir_f = JFFS2_INODE_INFO(dir_i);
 209
 210         /* jffs2_do_create() will want to lock it, _after_ reserving
 211            space and taking c-alloc_sem. If we keep it locked here,
 212            lockdep gets unhappy (although it's a false positive;
 213            nothing else will be looking at this inode yet so there's
 214            no chance of AB-BA deadlock involving its f->sem). */
 215         mutex_unlock(&f->sem);
 216
 217         ret = jffs2_do_create(c, dir_f, f, ri, &dentry->d_name);
 218         if (ret)
 219                 goto fail;
 220
 221         dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(ri->ctime));
 222
 223         jffs2_free_raw_inode(ri);
 224
 225         jffs2_dbg(1, "%s(): Created ino #%lu with mode %o, nlink %d(%d). nrpages %ld\n",
 226                   __func__, inode->i_ino, inode->i_mode, inode->i_nlink,
 227                   f->inocache->pino_nlink, inode->i_mapping->nrpages);
 228
 229         unlock_new_inode(inode);
 230         d_instantiate(dentry, inode);
 231         return 0;
 232
 233  fail:
 234         iget_failed(inode);
 235         jffs2_free_raw_inode(ri);
 236         return ret;
 237 }
 238
 239 /***********************************************************************/
 240
 241
 242 static int jffs2_unlink(struct inode *dir_i, struct dentry *dentry)
 243 {
 244         struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
 245         struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
 246         struct jffs2_inode_info *dead_f = JFFS2_INODE_INFO(dentry->d_inode);
 247         int ret;
 248         uint32_t now = get_seconds();
 249
 250         ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name,
 251                               dentry->d_name.len, dead_f, now);
 252         if (dead_f->inocache)
 253                 set_nlink(dentry->d_inode, dead_f->inocache->pino_nlink);
 254         if (!ret)
 255                 dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
 256         return ret;
 257 }
 258 /***********************************************************************/
 259
 260
 261 static int jffs2_link (struct dentry *old_dentry, struct inode *dir_i, struct dentry *dentry)
 262 {
 263         struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dentry->d_inode->i_sb);
 264         struct jffs2_inode_info *f = JFFS2_INODE_INFO(old_dentry->d_inode);
 265         struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
 266         int ret;
 267         uint8_t type;
 268         uint32_t now;
 269
 270         /* Don't let people make hard links to bad inodes. */
 271         if (!f->inocache)
 272                 return -EIO;
 273
 274         if (S_ISDIR(old_dentry->d_inode->i_mode))
 275                 return -EPERM;
 276
 277         /* XXX: This is ugly */
 278         type = (old_dentry->d_inode->i_mode & S_IFMT) >> 12;
 279         if (!type) type = DT_REG;
 280
 281         now = get_seconds();
 282         ret = jffs2_do_link(c, dir_f, f->inocache->ino, type, dentry->d_name.name, dentry->d_name.len, now);
 283
 284         if (!ret) {
 285                 mutex_lock(&f->sem);
 286                 set_nlink(old_dentry->d_inode, ++f->inocache->pino_nlink);
 287                 mutex_unlock(&f->sem);
 288                 d_instantiate(dentry, old_dentry->d_inode);
 289                 dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
 290                 ihold(old_dentry->d_inode);
 291         }
 292         return ret;
 293 }
 294
 295 /***********************************************************************/
 296
 297 static int jffs2_symlink (struct inode *dir_i, struct dentry *dentry, const char *target)
 298 {
 299         struct jffs2_inode_info *f, *dir_f;
 300         struct jffs2_sb_info *c;
 301         struct inode *inode;
 302         struct jffs2_raw_inode *ri;
 303         struct jffs2_raw_dirent *rd;
 304         struct jffs2_full_dnode *fn;
 305         struct jffs2_full_dirent *fd;
 306         int namelen;
 307         uint32_t alloclen;
 308         int ret, targetlen = strlen(target);
 309
 310         /* FIXME: If you care. We'd need to use frags for the target
 311            if it grows much more than this */
 312         if (targetlen > 254)
 313                 return -ENAMETOOLONG;
 314
 315         ri = jffs2_alloc_raw_inode();
 316
 317         if (!ri)
 318                 return -ENOMEM;
 319
 320         c = JFFS2_SB_INFO(dir_i->i_sb);
 321
 322         /* Try to reserve enough space for both node and dirent.
 323          * Just the node will do for now, though
 324          */
 325         namelen = dentry->d_name.len;
 326         ret = jffs2_reserve_space(c, sizeof(*ri) + targetlen, &alloclen,
 327                                   ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
 328
 329         if (ret) {
 330                 jffs2_free_raw_inode(ri);
 331                 return ret;
 332         }
 333
 334         inode = jffs2_new_inode(dir_i, S_IFLNK | S_IRWXUGO, ri);
 335
 336         if (IS_ERR(inode)) {
 337                 jffs2_free_raw_inode(ri);
 338                 jffs2_complete_reservation(c);
 339                 return PTR_ERR(inode);
 340         }
 341
 342         inode->i_op = &jffs2_symlink_inode_operations;
 343
 344         f = JFFS2_INODE_INFO(inode);
 345
 346         inode->i_size = targetlen;
 347         ri->isize = ri->dsize = ri->csize = cpu_to_je32(inode->i_size);
 348         ri->totlen = cpu_to_je32(sizeof(*ri) + inode->i_size);
 349         ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
 350
 351         ri->compr = JFFS2_COMPR_NONE;
 352         ri->data_crc = cpu_to_je32(crc32(0, target, targetlen));
 353         ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
 354
 355         fn = jffs2_write_dnode(c, f, ri, target, targetlen, ALLOC_NORMAL);
 356
 357         jffs2_free_raw_inode(ri);
 358
 359         if (IS_ERR(fn)) {
 360                 /* Eeek. Wave bye bye */
 361                 mutex_unlock(&f->sem);
 362                 jffs2_complete_reservation(c);
 363                 ret = PTR_ERR(fn);
 364                 goto fail;
 365         }
 366
 367         /* We use f->target field to store the target path. */
 368         f->target = kmemdup(target, targetlen + 1, GFP_KERNEL);
 369         if (!f->target) {
 370                 pr_warn("Can't allocate %d bytes of memory\n", targetlen + 1);
 371                 mutex_unlock(&f->sem);
 372                 jffs2_complete_reservation(c);
 373                 ret = -ENOMEM;
 374                 goto fail;
 375         }
 376
 377         jffs2_dbg(1, "%s(): symlink's target '%s' cached\n",
 378                   __func__, (char *)f->target);
 379
 380         /* No data here. Only a metadata node, which will be
 381            obsoleted by the first data write
 382         */
 383         f->metadata = fn;
 384         mutex_unlock(&f->sem);
 385
 386         jffs2_complete_reservation(c);
 387
 388         ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
 389         if (ret)
 390                 goto fail;
 391
 392         ret = jffs2_init_acl_post(inode);
 393         if (ret)
 394                 goto fail;
 395
 396         ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
 397                                   ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 398         if (ret)
 399                 goto fail;
 400
 401         rd = jffs2_alloc_raw_dirent();
 402         if (!rd) {
 403                 /* Argh. Now we treat it like a normal delete */
 404                 jffs2_complete_reservation(c);
 405                 ret = -ENOMEM;
 406                 goto fail;
 407         }
 408
 409         dir_f = JFFS2_INODE_INFO(dir_i);
 410         mutex_lock(&dir_f->sem);
 411
 412         rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
 413         rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
 414         rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
 415         rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
 416
 417         rd->pino = cpu_to_je32(dir_i->i_ino);
 418         rd->version = cpu_to_je32(++dir_f->highest_version);
 419         rd->ino = cpu_to_je32(inode->i_ino);
 420         rd->mctime = cpu_to_je32(get_seconds());
 421         rd->nsize = namelen;
 422         rd->type = DT_LNK;
 423         rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
 424         rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
 425
 426         fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
 427
 428         if (IS_ERR(fd)) {
 429                 /* dirent failed to write. Delete the inode normally
 430                    as if it were the final unlink() */
 431                 jffs2_complete_reservation(c);
 432                 jffs2_free_raw_dirent(rd);
 433                 mutex_unlock(&dir_f->sem);
 434                 ret = PTR_ERR(fd);
 435                 goto fail;
 436         }
 437
 438         dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
 439
 440         jffs2_free_raw_dirent(rd);
 441
 442         /* Link the fd into the inode's list, obsoleting an old
 443            one if necessary. */
 444         jffs2_add_fd_to_list(c, fd, &dir_f->dents);
 445
 446         mutex_unlock(&dir_f->sem);
 447         jffs2_complete_reservation(c);
 448
 449         unlock_new_inode(inode);
 450         d_instantiate(dentry, inode);
 451         return 0;
 452
 453  fail:
 454         iget_failed(inode);
 455         return ret;
 456 }
 457
 458
 459 static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, umode_t mode)
 460 {
 461         struct jffs2_inode_info *f, *dir_f;
 462         struct jffs2_sb_info *c;
 463         struct inode *inode;
 464         struct jffs2_raw_inode *ri;
 465         struct jffs2_raw_dirent *rd;
 466         struct jffs2_full_dnode *fn;
 467         struct jffs2_full_dirent *fd;
 468         int namelen;
 469         uint32_t alloclen;
 470         int ret;
 471
 472         mode |= S_IFDIR;
 473
 474         ri = jffs2_alloc_raw_inode();
 475         if (!ri)
 476                 return -ENOMEM;
 477
 478         c = JFFS2_SB_INFO(dir_i->i_sb);
 479
 480         /* Try to reserve enough space for both node and dirent.
 481          * Just the node will do for now, though
 482          */
 483         namelen = dentry->d_name.len;
 484         ret = jffs2_reserve_space(c, sizeof(*ri), &alloclen, ALLOC_NORMAL,
 485                                   JFFS2_SUMMARY_INODE_SIZE);
 486
 487         if (ret) {
 488                 jffs2_free_raw_inode(ri);
 489                 return ret;
 490         }
 491
 492         inode = jffs2_new_inode(dir_i, mode, ri);
 493
 494         if (IS_ERR(inode)) {
 495                 jffs2_free_raw_inode(ri);
 496                 jffs2_complete_reservation(c);
 497                 return PTR_ERR(inode);
 498         }
 499
 500         inode->i_op = &jffs2_dir_inode_operations;
 501         inode->i_fop = &jffs2_dir_operations;
 502
 503         f = JFFS2_INODE_INFO(inode);
 504
 505         /* Directories get nlink 2 at start */
 506         set_nlink(inode, 2);
 507         /* but ic->pino_nlink is the parent ino# */
 508         f->inocache->pino_nlink = dir_i->i_ino;
 509
 510         ri->data_crc = cpu_to_je32(0);
 511         ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
 512
 513         fn = jffs2_write_dnode(c, f, ri, NULL, 0, ALLOC_NORMAL);
 514
 515         jffs2_free_raw_inode(ri);
 516
 517         if (IS_ERR(fn)) {
 518                 /* Eeek. Wave bye bye */
 519                 mutex_unlock(&f->sem);
 520                 jffs2_complete_reservation(c);
 521                 ret = PTR_ERR(fn);
 522                 goto fail;
 523         }
 524         /* No data here. Only a metadata node, which will be
 525            obsoleted by the first data write
 526         */
 527         f->metadata = fn;
 528         mutex_unlock(&f->sem);
 529
 530         jffs2_complete_reservation(c);
 531
 532         ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
 533         if (ret)
 534                 goto fail;
 535
 536         ret = jffs2_init_acl_post(inode);
 537         if (ret)
 538                 goto fail;
 539
 540         ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
 541                                   ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 542         if (ret)
 543                 goto fail;
 544
 545         rd = jffs2_alloc_raw_dirent();
 546         if (!rd) {
 547                 /* Argh. Now we treat it like a normal delete */
 548                 jffs2_complete_reservation(c);
 549                 ret = -ENOMEM;
 550                 goto fail;
 551         }
 552
 553         dir_f = JFFS2_INODE_INFO(dir_i);
 554         mutex_lock(&dir_f->sem);
 555
 556         rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
 557         rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
 558         rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
 559         rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
 560
 561         rd->pino = cpu_to_je32(dir_i->i_ino);
 562         rd->version = cpu_to_je32(++dir_f->highest_version);
 563         rd->ino = cpu_to_je32(inode->i_ino);
 564         rd->mctime = cpu_to_je32(get_seconds());
 565         rd->nsize = namelen;
 566         rd->type = DT_DIR;
 567         rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
 568         rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
 569
 570         fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
 571
 572         if (IS_ERR(fd)) {
 573                 /* dirent failed to write. Delete the inode normally
 574                    as if it were the final unlink() */
 575                 jffs2_complete_reservation(c);
 576                 jffs2_free_raw_dirent(rd);
 577                 mutex_unlock(&dir_f->sem);
 578                 ret = PTR_ERR(fd);
 579                 goto fail;
 580         }
 581
 582         dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
 583         inc_nlink(dir_i);
 584
 585         jffs2_free_raw_dirent(rd);
 586
 587         /* Link the fd into the inode's list, obsoleting an old
 588            one if necessary. */
 589         jffs2_add_fd_to_list(c, fd, &dir_f->dents);
 590
 591         mutex_unlock(&dir_f->sem);
 592         jffs2_complete_reservation(c);
 593
 594         unlock_new_inode(inode);
 595         d_instantiate(dentry, inode);
 596         return 0;
 597
 598  fail:
 599         iget_failed(inode);
 600         return ret;
 601 }
 602
 603 static int jffs2_rmdir (struct inode *dir_i, struct dentry *dentry)
 604 {
 605         struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
 606         struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
 607         struct jffs2_inode_info *f = JFFS2_INODE_INFO(dentry->d_inode);
 608         struct jffs2_full_dirent *fd;
 609         int ret;
 610         uint32_t now = get_seconds();
 611
 612         for (fd = f->dents ; fd; fd = fd->next) {
 613                 if (fd->ino)
 614                         return -ENOTEMPTY;
 615         }
 616
 617         ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name,
 618                               dentry->d_name.len, f, now);
 619         if (!ret) {
 620                 dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
 621                 clear_nlink(dentry->d_inode);
 622                 drop_nlink(dir_i);
 623         }
 624         return ret;
 625 }
 626
 627 static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, umode_t mode, dev_t rdev)
 628 {
 629         struct jffs2_inode_info *f, *dir_f;
 630         struct jffs2_sb_info *c;
 631         struct inode *inode;
 632         struct jffs2_raw_inode *ri;
 633         struct jffs2_raw_dirent *rd;
 634         struct jffs2_full_dnode *fn;
 635         struct jffs2_full_dirent *fd;
 636         int namelen;
 637         union jffs2_device_node dev;
 638         int devlen = 0;
 639         uint32_t alloclen;
 640         int ret;
 641
 642         if (!new_valid_dev(rdev))
 643                 return -EINVAL;
 644
 645         ri = jffs2_alloc_raw_inode();
 646         if (!ri)
 647                 return -ENOMEM;
 648
 649         c = JFFS2_SB_INFO(dir_i->i_sb);
 650
 651         if (S_ISBLK(mode) || S_ISCHR(mode))
 652                 devlen = jffs2_encode_dev(&dev, rdev);
 653
 654         /* Try to reserve enough space for both node and dirent.
 655          * Just the node will do for now, though
 656          */
 657         namelen = dentry->d_name.len;
 658         ret = jffs2_reserve_space(c, sizeof(*ri) + devlen, &alloclen,
 659                                   ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
 660
 661         if (ret) {
 662                 jffs2_free_raw_inode(ri);
 663                 return ret;
 664         }
 665
 666         inode = jffs2_new_inode(dir_i, mode, ri);
 667
 668         if (IS_ERR(inode)) {
 669                 jffs2_free_raw_inode(ri);
 670                 jffs2_complete_reservation(c);
 671                 return PTR_ERR(inode);
 672         }
 673         inode->i_op = &jffs2_file_inode_operations;
 674         init_special_inode(inode, inode->i_mode, rdev);
 675
 676         f = JFFS2_INODE_INFO(inode);
 677
 678         ri->dsize = ri->csize = cpu_to_je32(devlen);
 679         ri->totlen = cpu_to_je32(sizeof(*ri) + devlen);
 680         ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
 681
 682         ri->compr = JFFS2_COMPR_NONE;
 683         ri->data_crc = cpu_to_je32(crc32(0, &dev, devlen));
 684         ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
 685
 686         fn = jffs2_write_dnode(c, f, ri, (char *)&dev, devlen, ALLOC_NORMAL);
 687
 688         jffs2_free_raw_inode(ri);
 689
 690         if (IS_ERR(fn)) {
 691                 /* Eeek. Wave bye bye */
 692                 mutex_unlock(&f->sem);
 693                 jffs2_complete_reservation(c);
 694                 ret = PTR_ERR(fn);
 695                 goto fail;
 696         }
 697         /* No data here. Only a metadata node, which will be
 698            obsoleted by the first data write
 699         */
 700         f->metadata = fn;
 701         mutex_unlock(&f->sem);
 702
 703         jffs2_complete_reservation(c);
 704
 705         ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
 706         if (ret)
 707                 goto fail;
 708
 709         ret = jffs2_init_acl_post(inode);
 710         if (ret)
 711                 goto fail;
 712
 713         ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
 714                                   ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 715         if (ret)
 716                 goto fail;
 717
 718         rd = jffs2_alloc_raw_dirent();
 719         if (!rd) {
 720                 /* Argh. Now we treat it like a normal delete */
 721                 jffs2_complete_reservation(c);
 722                 ret = -ENOMEM;
 723                 goto fail;
 724         }
 725
 726         dir_f = JFFS2_INODE_INFO(dir_i);
 727         mutex_lock(&dir_f->sem);
 728
 729         rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
 730         rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
 731         rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
 732         rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
 733
 734         rd->pino = cpu_to_je32(dir_i->i_ino);
 735         rd->version = cpu_to_je32(++dir_f->highest_version);
 736         rd->ino = cpu_to_je32(inode->i_ino);
 737         rd->mctime = cpu_to_je32(get_seconds());
 738         rd->nsize = namelen;
 739
 740         /* XXX: This is ugly. */
 741         rd->type = (mode & S_IFMT) >> 12;
 742
 743         rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
 744         rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
 745
 746         fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
 747
 748         if (IS_ERR(fd)) {
 749                 /* dirent failed to write. Delete the inode normally
 750                    as if it were the final unlink() */
 751                 jffs2_complete_reservation(c);
 752                 jffs2_free_raw_dirent(rd);
 753                 mutex_unlock(&dir_f->sem);
 754                 ret = PTR_ERR(fd);
 755                 goto fail;
 756         }
 757
 758         dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
 759
 760         jffs2_free_raw_dirent(rd);
 761
 762         /* Link the fd into the inode's list, obsoleting an old
 763            one if necessary. */
 764         jffs2_add_fd_to_list(c, fd, &dir_f->dents);
 765
 766         mutex_unlock(&dir_f->sem);
 767         jffs2_complete_reservation(c);
 768
 769         unlock_new_inode(inode);
 770         d_instantiate(dentry, inode);
 771         return 0;
 772
 773  fail:
 774         iget_failed(inode);
 775         return ret;
 776 }
 777
 778 static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry,
 779                          struct inode *new_dir_i, struct dentry *new_dentry)
 780 {
 781         int ret;
 782         struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dir_i->i_sb);
 783         struct jffs2_inode_info *victim_f = NULL;
 784         uint8_t type;
 785         uint32_t now;
 786
 787         /* The VFS will check for us and prevent trying to rename a
 788          * file over a directory and vice versa, but if it's a directory,
 789          * the VFS can't check whether the victim is empty. The filesystem
 790          * needs to do that for itself.
 791          */
 792         if (new_dentry->d_inode) {
 793                 victim_f = JFFS2_INODE_INFO(new_dentry->d_inode);
 794                 if (S_ISDIR(new_dentry->d_inode->i_mode)) {
 795                         struct jffs2_full_dirent *fd;
 796
 797                         mutex_lock(&victim_f->sem);
 798                         for (fd = victim_f->dents; fd; fd = fd->next) {
 799                                 if (fd->ino) {
 800                                         mutex_unlock(&victim_f->sem);
 801                                         return -ENOTEMPTY;
 802                                 }
 803                         }
 804                         mutex_unlock(&victim_f->sem);
 805                 }
 806         }
 807
 808         /* XXX: We probably ought to alloc enough space for
 809            both nodes at the same time. Writing the new link,
 810            then getting -ENOSPC, is quite bad :)
 811         */
 812
 813         /* Make a hard link */
 814
 815         /* XXX: This is ugly */
 816         type = (old_dentry->d_inode->i_mode & S_IFMT) >> 12;
 817         if (!type) type = DT_REG;
 818
 819         now = get_seconds();
 820         ret = jffs2_do_link(c, JFFS2_INODE_INFO(new_dir_i),
 821                             old_dentry->d_inode->i_ino, type,
 822                             new_dentry->d_name.name, new_dentry->d_name.len, now);
 823
 824         if (ret)
 825                 return ret;
 826
 827         if (victim_f) {
 828                 /* There was a victim. Kill it off nicely */
 829                 if (S_ISDIR(new_dentry->d_inode->i_mode))
 830                         clear_nlink(new_dentry->d_inode);
 831                 else
 832                         drop_nlink(new_dentry->d_inode);
 833                 /* Don't oops if the victim was a dirent pointing to an
 834                    inode which didn't exist. */
 835                 if (victim_f->inocache) {
 836                         mutex_lock(&victim_f->sem);
 837                         if (S_ISDIR(new_dentry->d_inode->i_mode))
 838                                 victim_f->inocache->pino_nlink = 0;
 839                         else
 840                                 victim_f->inocache->pino_nlink--;
 841                         mutex_unlock(&victim_f->sem);
 842                 }
 843         }
 844
 845         /* If it was a directory we moved, and there was no victim,
 846            increase i_nlink on its new parent */
 847         if (S_ISDIR(old_dentry->d_inode->i_mode) && !victim_f)
 848                 inc_nlink(new_dir_i);
 849
 850         /* Unlink the original */
 851         ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
 852                               old_dentry->d_name.name, old_dentry->d_name.len, NULL, now);
 853
 854         /* We don't touch inode->i_nlink */
 855
 856         if (ret) {
 857                 /* Oh shit. We really ought to make a single node which can do both atomically */
 858                 struct jffs2_inode_info *f = JFFS2_INODE_INFO(old_dentry->d_inode);
 859                 mutex_lock(&f->sem);
 860                 inc_nlink(old_dentry->d_inode);
 861                 if (f->inocache && !S_ISDIR(old_dentry->d_inode->i_mode))
 862                         f->inocache->pino_nlink++;
 863                 mutex_unlock(&f->sem);
 864
 865                 pr_notice("%s(): Link succeeded, unlink failed (err %d). You now have a hard link\n",
 866                           __func__, ret);
 867                 /* Might as well let the VFS know */
 868                 d_instantiate(new_dentry, old_dentry->d_inode);
 869                 ihold(old_dentry->d_inode);
 870                 new_dir_i->i_mtime = new_dir_i->i_ctime = ITIME(now);
 871                 return ret;
 872         }
 873
 874         if (S_ISDIR(old_dentry->d_inode->i_mode))
 875                 drop_nlink(old_dir_i);
 876
 877         new_dir_i->i_mtime = new_dir_i->i_ctime = old_dir_i->i_mtime = old_dir_i->i_ctime = ITIME(now);
 878
 879         return 0;
 880 }
 881