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 user_namespace *, struct inode *, 28 struct dentry *, umode_t, 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 user_namespace *, struct inode *, 34 struct dentry *, const char *); 35 static int jffs2_mkdir (struct user_namespace *, struct inode *,struct dentry *, 36 umode_t); 37 static int jffs2_rmdir (struct inode *,struct dentry *); 38 static int jffs2_mknod (struct user_namespace *, struct inode *,struct dentry *, 39 umode_t,dev_t); 40 static int jffs2_rename (struct user_namespace *, struct inode *, 41 struct dentry *, struct inode *, struct dentry *, 42 unsigned int); 43 44 const struct file_operations jffs2_dir_operations = 45 { 46 .read = generic_read_dir, 47 .iterate_shared=jffs2_readdir, 48 .unlocked_ioctl=jffs2_ioctl, 49 .fsync = jffs2_fsync, 50 .llseek = generic_file_llseek, 51 }; 52 53 54 const struct inode_operations jffs2_dir_inode_operations = 55 { 56 .create = jffs2_create, 57 .lookup = jffs2_lookup, 58 .link = jffs2_link, 59 .unlink = jffs2_unlink, 60 .symlink = jffs2_symlink, 61 .mkdir = jffs2_mkdir, 62 .rmdir = jffs2_rmdir, 63 .mknod = jffs2_mknod, 64 .rename = jffs2_rename, 65 .get_inode_acl = jffs2_get_acl, 66 .set_acl = jffs2_set_acl, 67 .setattr = jffs2_setattr, 68 .listxattr = jffs2_listxattr, 69 }; 70 71 /***********************************************************************/ 72 73 74 /* We keep the dirent list sorted in increasing order of name hash, 75 and we use the same hash function as the dentries. Makes this 76 nice and simple 77 */ 78 static struct dentry *jffs2_lookup(struct inode *dir_i, struct dentry *target, 79 unsigned int flags) 80 { 81 struct jffs2_inode_info *dir_f; 82 struct jffs2_full_dirent *fd = NULL, *fd_list; 83 uint32_t ino = 0; 84 struct inode *inode = NULL; 85 unsigned int nhash; 86 87 jffs2_dbg(1, "jffs2_lookup()\n"); 88 89 if (target->d_name.len > JFFS2_MAX_NAME_LEN) 90 return ERR_PTR(-ENAMETOOLONG); 91 92 dir_f = JFFS2_INODE_INFO(dir_i); 93 94 /* The 'nhash' on the fd_list is not the same as the dentry hash */ 95 nhash = full_name_hash(NULL, target->d_name.name, target->d_name.len); 96 97 mutex_lock(&dir_f->sem); 98 99 /* NB: The 2.2 backport will need to explicitly check for '.' and '..' here */ 100 for (fd_list = dir_f->dents; fd_list && fd_list->nhash <= nhash; fd_list = fd_list->next) { 101 if (fd_list->nhash == nhash && 102 (!fd || fd_list->version > fd->version) && 103 strlen(fd_list->name) == target->d_name.len && 104 !strncmp(fd_list->name, target->d_name.name, target->d_name.len)) { 105 fd = fd_list; 106 } 107 } 108 if (fd) 109 ino = fd->ino; 110 mutex_unlock(&dir_f->sem); 111 if (ino) { 112 inode = jffs2_iget(dir_i->i_sb, ino); 113 if (IS_ERR(inode)) 114 pr_warn("iget() failed for ino #%u\n", ino); 115 } 116 117 return d_splice_alias(inode, target); 118 } 119 120 /***********************************************************************/ 121 122 123 static int jffs2_readdir(struct file *file, struct dir_context *ctx) 124 { 125 struct inode *inode = file_inode(file); 126 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 127 struct jffs2_full_dirent *fd; 128 unsigned long curofs = 1; 129 130 jffs2_dbg(1, "jffs2_readdir() for dir_i #%lu\n", inode->i_ino); 131 132 if (!dir_emit_dots(file, ctx)) 133 return 0; 134 135 mutex_lock(&f->sem); 136 for (fd = f->dents; fd; fd = fd->next) { 137 curofs++; 138 /* First loop: curofs = 2; pos = 2 */ 139 if (curofs < ctx->pos) { 140 jffs2_dbg(2, "Skipping dirent: \"%s\", ino #%u, type %d, because curofs %ld < offset %ld\n", 141 fd->name, fd->ino, fd->type, curofs, (unsigned long)ctx->pos); 142 continue; 143 } 144 if (!fd->ino) { 145 jffs2_dbg(2, "Skipping deletion dirent \"%s\"\n", 146 fd->name); 147 ctx->pos++; 148 continue; 149 } 150 jffs2_dbg(2, "Dirent %ld: \"%s\", ino #%u, type %d\n", 151 (unsigned long)ctx->pos, fd->name, fd->ino, fd->type); 152 if (!dir_emit(ctx, fd->name, strlen(fd->name), fd->ino, fd->type)) 153 break; 154 ctx->pos++; 155 } 156 mutex_unlock(&f->sem); 157 return 0; 158 } 159 160 /***********************************************************************/ 161 162 163 static int jffs2_create(struct user_namespace *mnt_userns, struct inode *dir_i, 164 struct dentry *dentry, umode_t mode, bool excl) 165 { 166 struct jffs2_raw_inode *ri; 167 struct jffs2_inode_info *f, *dir_f; 168 struct jffs2_sb_info *c; 169 struct inode *inode; 170 int ret; 171 172 ri = jffs2_alloc_raw_inode(); 173 if (!ri) 174 return -ENOMEM; 175 176 c = JFFS2_SB_INFO(dir_i->i_sb); 177 178 jffs2_dbg(1, "%s()\n", __func__); 179 180 inode = jffs2_new_inode(dir_i, mode, ri); 181 182 if (IS_ERR(inode)) { 183 jffs2_dbg(1, "jffs2_new_inode() failed\n"); 184 jffs2_free_raw_inode(ri); 185 return PTR_ERR(inode); 186 } 187 188 inode->i_op = &jffs2_file_inode_operations; 189 inode->i_fop = &jffs2_file_operations; 190 inode->i_mapping->a_ops = &jffs2_file_address_operations; 191 inode->i_mapping->nrpages = 0; 192 193 f = JFFS2_INODE_INFO(inode); 194 dir_f = JFFS2_INODE_INFO(dir_i); 195 196 /* jffs2_do_create() will want to lock it, _after_ reserving 197 space and taking c-alloc_sem. If we keep it locked here, 198 lockdep gets unhappy (although it's a false positive; 199 nothing else will be looking at this inode yet so there's 200 no chance of AB-BA deadlock involving its f->sem). */ 201 mutex_unlock(&f->sem); 202 203 ret = jffs2_do_create(c, dir_f, f, ri, &dentry->d_name); 204 if (ret) 205 goto fail; 206 207 dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(ri->ctime)); 208 209 jffs2_free_raw_inode(ri); 210 211 jffs2_dbg(1, "%s(): Created ino #%lu with mode %o, nlink %d(%d). nrpages %ld\n", 212 __func__, inode->i_ino, inode->i_mode, inode->i_nlink, 213 f->inocache->pino_nlink, inode->i_mapping->nrpages); 214 215 d_instantiate_new(dentry, inode); 216 return 0; 217 218 fail: 219 iget_failed(inode); 220 jffs2_free_raw_inode(ri); 221 return ret; 222 } 223 224 /***********************************************************************/ 225 226 227 static int jffs2_unlink(struct inode *dir_i, struct dentry *dentry) 228 { 229 struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb); 230 struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i); 231 struct jffs2_inode_info *dead_f = JFFS2_INODE_INFO(d_inode(dentry)); 232 int ret; 233 uint32_t now = JFFS2_NOW(); 234 235 ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name, 236 dentry->d_name.len, dead_f, now); 237 if (dead_f->inocache) 238 set_nlink(d_inode(dentry), dead_f->inocache->pino_nlink); 239 if (!ret) 240 dir_i->i_mtime = dir_i->i_ctime = ITIME(now); 241 return ret; 242 } 243 /***********************************************************************/ 244 245 246 static int jffs2_link (struct dentry *old_dentry, struct inode *dir_i, struct dentry *dentry) 247 { 248 struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dentry->d_sb); 249 struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(old_dentry)); 250 struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i); 251 int ret; 252 uint8_t type; 253 uint32_t now; 254 255 /* Don't let people make hard links to bad inodes. */ 256 if (!f->inocache) 257 return -EIO; 258 259 if (d_is_dir(old_dentry)) 260 return -EPERM; 261 262 /* XXX: This is ugly */ 263 type = (d_inode(old_dentry)->i_mode & S_IFMT) >> 12; 264 if (!type) type = DT_REG; 265 266 now = JFFS2_NOW(); 267 ret = jffs2_do_link(c, dir_f, f->inocache->ino, type, dentry->d_name.name, dentry->d_name.len, now); 268 269 if (!ret) { 270 mutex_lock(&f->sem); 271 set_nlink(d_inode(old_dentry), ++f->inocache->pino_nlink); 272 mutex_unlock(&f->sem); 273 d_instantiate(dentry, d_inode(old_dentry)); 274 dir_i->i_mtime = dir_i->i_ctime = ITIME(now); 275 ihold(d_inode(old_dentry)); 276 } 277 return ret; 278 } 279 280 /***********************************************************************/ 281 282 static int jffs2_symlink (struct user_namespace *mnt_userns, struct inode *dir_i, 283 struct dentry *dentry, const char *target) 284 { 285 struct jffs2_inode_info *f, *dir_f; 286 struct jffs2_sb_info *c; 287 struct inode *inode; 288 struct jffs2_raw_inode *ri; 289 struct jffs2_raw_dirent *rd; 290 struct jffs2_full_dnode *fn; 291 struct jffs2_full_dirent *fd; 292 int namelen; 293 uint32_t alloclen; 294 int ret, targetlen = strlen(target); 295 296 /* FIXME: If you care. We'd need to use frags for the target 297 if it grows much more than this */ 298 if (targetlen > 254) 299 return -ENAMETOOLONG; 300 301 ri = jffs2_alloc_raw_inode(); 302 303 if (!ri) 304 return -ENOMEM; 305 306 c = JFFS2_SB_INFO(dir_i->i_sb); 307 308 /* Try to reserve enough space for both node and dirent. 309 * Just the node will do for now, though 310 */ 311 namelen = dentry->d_name.len; 312 ret = jffs2_reserve_space(c, sizeof(*ri) + targetlen, &alloclen, 313 ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE); 314 315 if (ret) { 316 jffs2_free_raw_inode(ri); 317 return ret; 318 } 319 320 inode = jffs2_new_inode(dir_i, S_IFLNK | S_IRWXUGO, ri); 321 322 if (IS_ERR(inode)) { 323 jffs2_free_raw_inode(ri); 324 jffs2_complete_reservation(c); 325 return PTR_ERR(inode); 326 } 327 328 inode->i_op = &jffs2_symlink_inode_operations; 329 330 f = JFFS2_INODE_INFO(inode); 331 332 inode->i_size = targetlen; 333 ri->isize = ri->dsize = ri->csize = cpu_to_je32(inode->i_size); 334 ri->totlen = cpu_to_je32(sizeof(*ri) + inode->i_size); 335 ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4)); 336 337 ri->compr = JFFS2_COMPR_NONE; 338 ri->data_crc = cpu_to_je32(crc32(0, target, targetlen)); 339 ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8)); 340 341 fn = jffs2_write_dnode(c, f, ri, target, targetlen, ALLOC_NORMAL); 342 343 jffs2_free_raw_inode(ri); 344 345 if (IS_ERR(fn)) { 346 /* Eeek. Wave bye bye */ 347 mutex_unlock(&f->sem); 348 jffs2_complete_reservation(c); 349 ret = PTR_ERR(fn); 350 goto fail; 351 } 352 353 /* We use f->target field to store the target path. */ 354 f->target = kmemdup(target, targetlen + 1, GFP_KERNEL); 355 if (!f->target) { 356 pr_warn("Can't allocate %d bytes of memory\n", targetlen + 1); 357 mutex_unlock(&f->sem); 358 jffs2_complete_reservation(c); 359 ret = -ENOMEM; 360 goto fail; 361 } 362 inode->i_link = f->target; 363 364 jffs2_dbg(1, "%s(): symlink's target '%s' cached\n", 365 __func__, (char *)f->target); 366 367 /* No data here. Only a metadata node, which will be 368 obsoleted by the first data write 369 */ 370 f->metadata = fn; 371 mutex_unlock(&f->sem); 372 373 jffs2_complete_reservation(c); 374 375 ret = jffs2_init_security(inode, dir_i, &dentry->d_name); 376 if (ret) 377 goto fail; 378 379 ret = jffs2_init_acl_post(inode); 380 if (ret) 381 goto fail; 382 383 ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen, 384 ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen)); 385 if (ret) 386 goto fail; 387 388 rd = jffs2_alloc_raw_dirent(); 389 if (!rd) { 390 /* Argh. Now we treat it like a normal delete */ 391 jffs2_complete_reservation(c); 392 ret = -ENOMEM; 393 goto fail; 394 } 395 396 dir_f = JFFS2_INODE_INFO(dir_i); 397 mutex_lock(&dir_f->sem); 398 399 rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 400 rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT); 401 rd->totlen = cpu_to_je32(sizeof(*rd) + namelen); 402 rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4)); 403 404 rd->pino = cpu_to_je32(dir_i->i_ino); 405 rd->version = cpu_to_je32(++dir_f->highest_version); 406 rd->ino = cpu_to_je32(inode->i_ino); 407 rd->mctime = cpu_to_je32(JFFS2_NOW()); 408 rd->nsize = namelen; 409 rd->type = DT_LNK; 410 rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8)); 411 rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen)); 412 413 fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL); 414 415 if (IS_ERR(fd)) { 416 /* dirent failed to write. Delete the inode normally 417 as if it were the final unlink() */ 418 jffs2_complete_reservation(c); 419 jffs2_free_raw_dirent(rd); 420 mutex_unlock(&dir_f->sem); 421 ret = PTR_ERR(fd); 422 goto fail; 423 } 424 425 dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime)); 426 427 jffs2_free_raw_dirent(rd); 428 429 /* Link the fd into the inode's list, obsoleting an old 430 one if necessary. */ 431 jffs2_add_fd_to_list(c, fd, &dir_f->dents); 432 433 mutex_unlock(&dir_f->sem); 434 jffs2_complete_reservation(c); 435 436 d_instantiate_new(dentry, inode); 437 return 0; 438 439 fail: 440 iget_failed(inode); 441 return ret; 442 } 443 444 445 static int jffs2_mkdir (struct user_namespace *mnt_userns, struct inode *dir_i, 446 struct dentry *dentry, umode_t mode) 447 { 448 struct jffs2_inode_info *f, *dir_f; 449 struct jffs2_sb_info *c; 450 struct inode *inode; 451 struct jffs2_raw_inode *ri; 452 struct jffs2_raw_dirent *rd; 453 struct jffs2_full_dnode *fn; 454 struct jffs2_full_dirent *fd; 455 int namelen; 456 uint32_t alloclen; 457 int ret; 458 459 mode |= S_IFDIR; 460 461 ri = jffs2_alloc_raw_inode(); 462 if (!ri) 463 return -ENOMEM; 464 465 c = JFFS2_SB_INFO(dir_i->i_sb); 466 467 /* Try to reserve enough space for both node and dirent. 468 * Just the node will do for now, though 469 */ 470 namelen = dentry->d_name.len; 471 ret = jffs2_reserve_space(c, sizeof(*ri), &alloclen, ALLOC_NORMAL, 472 JFFS2_SUMMARY_INODE_SIZE); 473 474 if (ret) { 475 jffs2_free_raw_inode(ri); 476 return ret; 477 } 478 479 inode = jffs2_new_inode(dir_i, mode, ri); 480 481 if (IS_ERR(inode)) { 482 jffs2_free_raw_inode(ri); 483 jffs2_complete_reservation(c); 484 return PTR_ERR(inode); 485 } 486 487 inode->i_op = &jffs2_dir_inode_operations; 488 inode->i_fop = &jffs2_dir_operations; 489 490 f = JFFS2_INODE_INFO(inode); 491 492 /* Directories get nlink 2 at start */ 493 set_nlink(inode, 2); 494 /* but ic->pino_nlink is the parent ino# */ 495 f->inocache->pino_nlink = dir_i->i_ino; 496 497 ri->data_crc = cpu_to_je32(0); 498 ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8)); 499 500 fn = jffs2_write_dnode(c, f, ri, NULL, 0, ALLOC_NORMAL); 501 502 jffs2_free_raw_inode(ri); 503 504 if (IS_ERR(fn)) { 505 /* Eeek. Wave bye bye */ 506 mutex_unlock(&f->sem); 507 jffs2_complete_reservation(c); 508 ret = PTR_ERR(fn); 509 goto fail; 510 } 511 /* No data here. Only a metadata node, which will be 512 obsoleted by the first data write 513 */ 514 f->metadata = fn; 515 mutex_unlock(&f->sem); 516 517 jffs2_complete_reservation(c); 518 519 ret = jffs2_init_security(inode, dir_i, &dentry->d_name); 520 if (ret) 521 goto fail; 522 523 ret = jffs2_init_acl_post(inode); 524 if (ret) 525 goto fail; 526 527 ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen, 528 ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen)); 529 if (ret) 530 goto fail; 531 532 rd = jffs2_alloc_raw_dirent(); 533 if (!rd) { 534 /* Argh. Now we treat it like a normal delete */ 535 jffs2_complete_reservation(c); 536 ret = -ENOMEM; 537 goto fail; 538 } 539 540 dir_f = JFFS2_INODE_INFO(dir_i); 541 mutex_lock(&dir_f->sem); 542 543 rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 544 rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT); 545 rd->totlen = cpu_to_je32(sizeof(*rd) + namelen); 546 rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4)); 547 548 rd->pino = cpu_to_je32(dir_i->i_ino); 549 rd->version = cpu_to_je32(++dir_f->highest_version); 550 rd->ino = cpu_to_je32(inode->i_ino); 551 rd->mctime = cpu_to_je32(JFFS2_NOW()); 552 rd->nsize = namelen; 553 rd->type = DT_DIR; 554 rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8)); 555 rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen)); 556 557 fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL); 558 559 if (IS_ERR(fd)) { 560 /* dirent failed to write. Delete the inode normally 561 as if it were the final unlink() */ 562 jffs2_complete_reservation(c); 563 jffs2_free_raw_dirent(rd); 564 mutex_unlock(&dir_f->sem); 565 ret = PTR_ERR(fd); 566 goto fail; 567 } 568 569 dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime)); 570 inc_nlink(dir_i); 571 572 jffs2_free_raw_dirent(rd); 573 574 /* Link the fd into the inode's list, obsoleting an old 575 one if necessary. */ 576 jffs2_add_fd_to_list(c, fd, &dir_f->dents); 577 578 mutex_unlock(&dir_f->sem); 579 jffs2_complete_reservation(c); 580 581 d_instantiate_new(dentry, inode); 582 return 0; 583 584 fail: 585 iget_failed(inode); 586 return ret; 587 } 588 589 static int jffs2_rmdir (struct inode *dir_i, struct dentry *dentry) 590 { 591 struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb); 592 struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i); 593 struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(dentry)); 594 struct jffs2_full_dirent *fd; 595 int ret; 596 uint32_t now = JFFS2_NOW(); 597 598 mutex_lock(&f->sem); 599 for (fd = f->dents ; fd; fd = fd->next) { 600 if (fd->ino) { 601 mutex_unlock(&f->sem); 602 return -ENOTEMPTY; 603 } 604 } 605 mutex_unlock(&f->sem); 606 607 ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name, 608 dentry->d_name.len, f, now); 609 if (!ret) { 610 dir_i->i_mtime = dir_i->i_ctime = ITIME(now); 611 clear_nlink(d_inode(dentry)); 612 drop_nlink(dir_i); 613 } 614 return ret; 615 } 616 617 static int jffs2_mknod (struct user_namespace *mnt_userns, struct inode *dir_i, 618 struct dentry *dentry, umode_t mode, dev_t rdev) 619 { 620 struct jffs2_inode_info *f, *dir_f; 621 struct jffs2_sb_info *c; 622 struct inode *inode; 623 struct jffs2_raw_inode *ri; 624 struct jffs2_raw_dirent *rd; 625 struct jffs2_full_dnode *fn; 626 struct jffs2_full_dirent *fd; 627 int namelen; 628 union jffs2_device_node dev; 629 int devlen = 0; 630 uint32_t alloclen; 631 int ret; 632 633 ri = jffs2_alloc_raw_inode(); 634 if (!ri) 635 return -ENOMEM; 636 637 c = JFFS2_SB_INFO(dir_i->i_sb); 638 639 if (S_ISBLK(mode) || S_ISCHR(mode)) 640 devlen = jffs2_encode_dev(&dev, rdev); 641 642 /* Try to reserve enough space for both node and dirent. 643 * Just the node will do for now, though 644 */ 645 namelen = dentry->d_name.len; 646 ret = jffs2_reserve_space(c, sizeof(*ri) + devlen, &alloclen, 647 ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE); 648 649 if (ret) { 650 jffs2_free_raw_inode(ri); 651 return ret; 652 } 653 654 inode = jffs2_new_inode(dir_i, mode, ri); 655 656 if (IS_ERR(inode)) { 657 jffs2_free_raw_inode(ri); 658 jffs2_complete_reservation(c); 659 return PTR_ERR(inode); 660 } 661 inode->i_op = &jffs2_file_inode_operations; 662 init_special_inode(inode, inode->i_mode, rdev); 663 664 f = JFFS2_INODE_INFO(inode); 665 666 ri->dsize = ri->csize = cpu_to_je32(devlen); 667 ri->totlen = cpu_to_je32(sizeof(*ri) + devlen); 668 ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4)); 669 670 ri->compr = JFFS2_COMPR_NONE; 671 ri->data_crc = cpu_to_je32(crc32(0, &dev, devlen)); 672 ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8)); 673 674 fn = jffs2_write_dnode(c, f, ri, (char *)&dev, devlen, ALLOC_NORMAL); 675 676 jffs2_free_raw_inode(ri); 677 678 if (IS_ERR(fn)) { 679 /* Eeek. Wave bye bye */ 680 mutex_unlock(&f->sem); 681 jffs2_complete_reservation(c); 682 ret = PTR_ERR(fn); 683 goto fail; 684 } 685 /* No data here. Only a metadata node, which will be 686 obsoleted by the first data write 687 */ 688 f->metadata = fn; 689 mutex_unlock(&f->sem); 690 691 jffs2_complete_reservation(c); 692 693 ret = jffs2_init_security(inode, dir_i, &dentry->d_name); 694 if (ret) 695 goto fail; 696 697 ret = jffs2_init_acl_post(inode); 698 if (ret) 699 goto fail; 700 701 ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen, 702 ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen)); 703 if (ret) 704 goto fail; 705 706 rd = jffs2_alloc_raw_dirent(); 707 if (!rd) { 708 /* Argh. Now we treat it like a normal delete */ 709 jffs2_complete_reservation(c); 710 ret = -ENOMEM; 711 goto fail; 712 } 713 714 dir_f = JFFS2_INODE_INFO(dir_i); 715 mutex_lock(&dir_f->sem); 716 717 rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 718 rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT); 719 rd->totlen = cpu_to_je32(sizeof(*rd) + namelen); 720 rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4)); 721 722 rd->pino = cpu_to_je32(dir_i->i_ino); 723 rd->version = cpu_to_je32(++dir_f->highest_version); 724 rd->ino = cpu_to_je32(inode->i_ino); 725 rd->mctime = cpu_to_je32(JFFS2_NOW()); 726 rd->nsize = namelen; 727 728 /* XXX: This is ugly. */ 729 rd->type = (mode & S_IFMT) >> 12; 730 731 rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8)); 732 rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen)); 733 734 fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL); 735 736 if (IS_ERR(fd)) { 737 /* dirent failed to write. Delete the inode normally 738 as if it were the final unlink() */ 739 jffs2_complete_reservation(c); 740 jffs2_free_raw_dirent(rd); 741 mutex_unlock(&dir_f->sem); 742 ret = PTR_ERR(fd); 743 goto fail; 744 } 745 746 dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime)); 747 748 jffs2_free_raw_dirent(rd); 749 750 /* Link the fd into the inode's list, obsoleting an old 751 one if necessary. */ 752 jffs2_add_fd_to_list(c, fd, &dir_f->dents); 753 754 mutex_unlock(&dir_f->sem); 755 jffs2_complete_reservation(c); 756 757 d_instantiate_new(dentry, inode); 758 return 0; 759 760 fail: 761 iget_failed(inode); 762 return ret; 763 } 764 765 static int jffs2_rename (struct user_namespace *mnt_userns, 766 struct inode *old_dir_i, struct dentry *old_dentry, 767 struct inode *new_dir_i, struct dentry *new_dentry, 768 unsigned int flags) 769 { 770 int ret; 771 struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dir_i->i_sb); 772 struct jffs2_inode_info *victim_f = NULL; 773 uint8_t type; 774 uint32_t now; 775 776 if (flags & ~RENAME_NOREPLACE) 777 return -EINVAL; 778 779 /* The VFS will check for us and prevent trying to rename a 780 * file over a directory and vice versa, but if it's a directory, 781 * the VFS can't check whether the victim is empty. The filesystem 782 * needs to do that for itself. 783 */ 784 if (d_really_is_positive(new_dentry)) { 785 victim_f = JFFS2_INODE_INFO(d_inode(new_dentry)); 786 if (d_is_dir(new_dentry)) { 787 struct jffs2_full_dirent *fd; 788 789 mutex_lock(&victim_f->sem); 790 for (fd = victim_f->dents; fd; fd = fd->next) { 791 if (fd->ino) { 792 mutex_unlock(&victim_f->sem); 793 return -ENOTEMPTY; 794 } 795 } 796 mutex_unlock(&victim_f->sem); 797 } 798 } 799 800 /* XXX: We probably ought to alloc enough space for 801 both nodes at the same time. Writing the new link, 802 then getting -ENOSPC, is quite bad :) 803 */ 804 805 /* Make a hard link */ 806 807 /* XXX: This is ugly */ 808 type = (d_inode(old_dentry)->i_mode & S_IFMT) >> 12; 809 if (!type) type = DT_REG; 810 811 now = JFFS2_NOW(); 812 ret = jffs2_do_link(c, JFFS2_INODE_INFO(new_dir_i), 813 d_inode(old_dentry)->i_ino, type, 814 new_dentry->d_name.name, new_dentry->d_name.len, now); 815 816 if (ret) 817 return ret; 818 819 if (victim_f) { 820 /* There was a victim. Kill it off nicely */ 821 if (d_is_dir(new_dentry)) 822 clear_nlink(d_inode(new_dentry)); 823 else 824 drop_nlink(d_inode(new_dentry)); 825 /* Don't oops if the victim was a dirent pointing to an 826 inode which didn't exist. */ 827 if (victim_f->inocache) { 828 mutex_lock(&victim_f->sem); 829 if (d_is_dir(new_dentry)) 830 victim_f->inocache->pino_nlink = 0; 831 else 832 victim_f->inocache->pino_nlink--; 833 mutex_unlock(&victim_f->sem); 834 } 835 } 836 837 /* If it was a directory we moved, and there was no victim, 838 increase i_nlink on its new parent */ 839 if (d_is_dir(old_dentry) && !victim_f) 840 inc_nlink(new_dir_i); 841 842 /* Unlink the original */ 843 ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i), 844 old_dentry->d_name.name, old_dentry->d_name.len, NULL, now); 845 846 /* We don't touch inode->i_nlink */ 847 848 if (ret) { 849 /* Oh shit. We really ought to make a single node which can do both atomically */ 850 struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(old_dentry)); 851 mutex_lock(&f->sem); 852 inc_nlink(d_inode(old_dentry)); 853 if (f->inocache && !d_is_dir(old_dentry)) 854 f->inocache->pino_nlink++; 855 mutex_unlock(&f->sem); 856 857 pr_notice("%s(): Link succeeded, unlink failed (err %d). You now have a hard link\n", 858 __func__, ret); 859 /* 860 * We can't keep the target in dcache after that. 861 * For one thing, we can't afford dentry aliases for directories. 862 * For another, if there was a victim, we _can't_ set new inode 863 * for that sucker and we have to trigger mount eviction - the 864 * caller won't do it on its own since we are returning an error. 865 */ 866 d_invalidate(new_dentry); 867 new_dir_i->i_mtime = new_dir_i->i_ctime = ITIME(now); 868 return ret; 869 } 870 871 if (d_is_dir(old_dentry)) 872 drop_nlink(old_dir_i); 873 874 new_dir_i->i_mtime = new_dir_i->i_ctime = old_dir_i->i_mtime = old_dir_i->i_ctime = ITIME(now); 875 876 return 0; 877 } 878 879