1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* dir.c: AFS filesystem directory handling 3 * 4 * Copyright (C) 2002, 2018 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/fs.h> 10 #include <linux/namei.h> 11 #include <linux/pagemap.h> 12 #include <linux/swap.h> 13 #include <linux/ctype.h> 14 #include <linux/sched.h> 15 #include <linux/task_io_accounting_ops.h> 16 #include "internal.h" 17 #include "afs_fs.h" 18 #include "xdr_fs.h" 19 20 static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry, 21 unsigned int flags); 22 static int afs_dir_open(struct inode *inode, struct file *file); 23 static int afs_readdir(struct file *file, struct dir_context *ctx); 24 static int afs_d_revalidate(struct dentry *dentry, unsigned int flags); 25 static int afs_d_delete(const struct dentry *dentry); 26 static void afs_d_iput(struct dentry *dentry, struct inode *inode); 27 static int afs_lookup_one_filldir(struct dir_context *ctx, const char *name, int nlen, 28 loff_t fpos, u64 ino, unsigned dtype); 29 static int afs_lookup_filldir(struct dir_context *ctx, const char *name, int nlen, 30 loff_t fpos, u64 ino, unsigned dtype); 31 static int afs_create(struct user_namespace *mnt_userns, struct inode *dir, 32 struct dentry *dentry, umode_t mode, bool excl); 33 static int afs_mkdir(struct user_namespace *mnt_userns, struct inode *dir, 34 struct dentry *dentry, umode_t mode); 35 static int afs_rmdir(struct inode *dir, struct dentry *dentry); 36 static int afs_unlink(struct inode *dir, struct dentry *dentry); 37 static int afs_link(struct dentry *from, struct inode *dir, 38 struct dentry *dentry); 39 static int afs_symlink(struct user_namespace *mnt_userns, struct inode *dir, 40 struct dentry *dentry, const char *content); 41 static int afs_rename(struct user_namespace *mnt_userns, struct inode *old_dir, 42 struct dentry *old_dentry, struct inode *new_dir, 43 struct dentry *new_dentry, unsigned int flags); 44 static int afs_dir_releasepage(struct page *page, gfp_t gfp_flags); 45 static void afs_dir_invalidatepage(struct page *page, unsigned int offset, 46 unsigned int length); 47 48 static int afs_dir_set_page_dirty(struct page *page) 49 { 50 BUG(); /* This should never happen. */ 51 } 52 53 const struct file_operations afs_dir_file_operations = { 54 .open = afs_dir_open, 55 .release = afs_release, 56 .iterate_shared = afs_readdir, 57 .lock = afs_lock, 58 .llseek = generic_file_llseek, 59 }; 60 61 const struct inode_operations afs_dir_inode_operations = { 62 .create = afs_create, 63 .lookup = afs_lookup, 64 .link = afs_link, 65 .unlink = afs_unlink, 66 .symlink = afs_symlink, 67 .mkdir = afs_mkdir, 68 .rmdir = afs_rmdir, 69 .rename = afs_rename, 70 .permission = afs_permission, 71 .getattr = afs_getattr, 72 .setattr = afs_setattr, 73 }; 74 75 const struct address_space_operations afs_dir_aops = { 76 .set_page_dirty = afs_dir_set_page_dirty, 77 .releasepage = afs_dir_releasepage, 78 .invalidatepage = afs_dir_invalidatepage, 79 }; 80 81 const struct dentry_operations afs_fs_dentry_operations = { 82 .d_revalidate = afs_d_revalidate, 83 .d_delete = afs_d_delete, 84 .d_release = afs_d_release, 85 .d_automount = afs_d_automount, 86 .d_iput = afs_d_iput, 87 }; 88 89 struct afs_lookup_one_cookie { 90 struct dir_context ctx; 91 struct qstr name; 92 bool found; 93 struct afs_fid fid; 94 }; 95 96 struct afs_lookup_cookie { 97 struct dir_context ctx; 98 struct qstr name; 99 bool found; 100 bool one_only; 101 unsigned short nr_fids; 102 struct afs_fid fids[50]; 103 }; 104 105 /* 106 * Drop the refs that we're holding on the pages we were reading into. We've 107 * got refs on the first nr_pages pages. 108 */ 109 static void afs_dir_read_cleanup(struct afs_read *req) 110 { 111 struct address_space *mapping = req->vnode->vfs_inode.i_mapping; 112 struct page *page; 113 pgoff_t last = req->nr_pages - 1; 114 115 XA_STATE(xas, &mapping->i_pages, 0); 116 117 if (unlikely(!req->nr_pages)) 118 return; 119 120 rcu_read_lock(); 121 xas_for_each(&xas, page, last) { 122 if (xas_retry(&xas, page)) 123 continue; 124 BUG_ON(xa_is_value(page)); 125 BUG_ON(PageCompound(page)); 126 ASSERTCMP(page->mapping, ==, mapping); 127 128 put_page(page); 129 } 130 131 rcu_read_unlock(); 132 } 133 134 /* 135 * check that a directory page is valid 136 */ 137 static bool afs_dir_check_page(struct afs_vnode *dvnode, struct page *page, 138 loff_t i_size) 139 { 140 struct afs_xdr_dir_page *dbuf; 141 loff_t latter, off; 142 int tmp, qty; 143 144 /* Determine how many magic numbers there should be in this page, but 145 * we must take care because the directory may change size under us. 146 */ 147 off = page_offset(page); 148 if (i_size <= off) 149 goto checked; 150 151 latter = i_size - off; 152 if (latter >= PAGE_SIZE) 153 qty = PAGE_SIZE; 154 else 155 qty = latter; 156 qty /= sizeof(union afs_xdr_dir_block); 157 158 /* check them */ 159 dbuf = kmap_atomic(page); 160 for (tmp = 0; tmp < qty; tmp++) { 161 if (dbuf->blocks[tmp].hdr.magic != AFS_DIR_MAGIC) { 162 printk("kAFS: %s(%lx): bad magic %d/%d is %04hx\n", 163 __func__, dvnode->vfs_inode.i_ino, tmp, qty, 164 ntohs(dbuf->blocks[tmp].hdr.magic)); 165 trace_afs_dir_check_failed(dvnode, off, i_size); 166 kunmap(page); 167 trace_afs_file_error(dvnode, -EIO, afs_file_error_dir_bad_magic); 168 goto error; 169 } 170 171 /* Make sure each block is NUL terminated so we can reasonably 172 * use string functions on it. The filenames in the page 173 * *should* be NUL-terminated anyway. 174 */ 175 ((u8 *)&dbuf->blocks[tmp])[AFS_DIR_BLOCK_SIZE - 1] = 0; 176 } 177 178 kunmap_atomic(dbuf); 179 180 checked: 181 afs_stat_v(dvnode, n_read_dir); 182 return true; 183 184 error: 185 return false; 186 } 187 188 /* 189 * Dump the contents of a directory. 190 */ 191 static void afs_dir_dump(struct afs_vnode *dvnode, struct afs_read *req) 192 { 193 struct afs_xdr_dir_page *dbuf; 194 struct address_space *mapping = dvnode->vfs_inode.i_mapping; 195 struct page *page; 196 unsigned int i, qty = PAGE_SIZE / sizeof(union afs_xdr_dir_block); 197 pgoff_t last = req->nr_pages - 1; 198 199 XA_STATE(xas, &mapping->i_pages, 0); 200 201 pr_warn("DIR %llx:%llx f=%llx l=%llx al=%llx\n", 202 dvnode->fid.vid, dvnode->fid.vnode, 203 req->file_size, req->len, req->actual_len); 204 pr_warn("DIR %llx %x %zx %zx\n", 205 req->pos, req->nr_pages, 206 req->iter->iov_offset, iov_iter_count(req->iter)); 207 208 xas_for_each(&xas, page, last) { 209 if (xas_retry(&xas, page)) 210 continue; 211 212 BUG_ON(PageCompound(page)); 213 BUG_ON(page->mapping != mapping); 214 215 dbuf = kmap_atomic(page); 216 for (i = 0; i < qty; i++) { 217 union afs_xdr_dir_block *block = &dbuf->blocks[i]; 218 219 pr_warn("[%02lx] %32phN\n", page->index * qty + i, block); 220 } 221 kunmap_atomic(dbuf); 222 } 223 } 224 225 /* 226 * Check all the pages in a directory. All the pages are held pinned. 227 */ 228 static int afs_dir_check(struct afs_vnode *dvnode, struct afs_read *req) 229 { 230 struct address_space *mapping = dvnode->vfs_inode.i_mapping; 231 struct page *page; 232 pgoff_t last = req->nr_pages - 1; 233 int ret = 0; 234 235 XA_STATE(xas, &mapping->i_pages, 0); 236 237 if (unlikely(!req->nr_pages)) 238 return 0; 239 240 rcu_read_lock(); 241 xas_for_each(&xas, page, last) { 242 if (xas_retry(&xas, page)) 243 continue; 244 245 BUG_ON(PageCompound(page)); 246 BUG_ON(page->mapping != mapping); 247 248 if (!afs_dir_check_page(dvnode, page, req->file_size)) { 249 afs_dir_dump(dvnode, req); 250 ret = -EIO; 251 break; 252 } 253 } 254 255 rcu_read_unlock(); 256 return ret; 257 } 258 259 /* 260 * open an AFS directory file 261 */ 262 static int afs_dir_open(struct inode *inode, struct file *file) 263 { 264 _enter("{%lu}", inode->i_ino); 265 266 BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048); 267 BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32); 268 269 if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(inode)->flags)) 270 return -ENOENT; 271 272 return afs_open(inode, file); 273 } 274 275 /* 276 * Read the directory into the pagecache in one go, scrubbing the previous 277 * contents. The list of pages is returned, pinning them so that they don't 278 * get reclaimed during the iteration. 279 */ 280 static struct afs_read *afs_read_dir(struct afs_vnode *dvnode, struct key *key) 281 __acquires(&dvnode->validate_lock) 282 { 283 struct afs_read *req; 284 loff_t i_size; 285 int nr_pages, i, n; 286 int ret; 287 288 _enter(""); 289 290 req = kzalloc(sizeof(*req), GFP_KERNEL); 291 if (!req) 292 return ERR_PTR(-ENOMEM); 293 294 refcount_set(&req->usage, 1); 295 req->vnode = dvnode; 296 req->key = key_get(key); 297 req->cleanup = afs_dir_read_cleanup; 298 299 expand: 300 i_size = i_size_read(&dvnode->vfs_inode); 301 if (i_size < 2048) { 302 ret = afs_bad(dvnode, afs_file_error_dir_small); 303 goto error; 304 } 305 if (i_size > 2048 * 1024) { 306 trace_afs_file_error(dvnode, -EFBIG, afs_file_error_dir_big); 307 ret = -EFBIG; 308 goto error; 309 } 310 311 _enter("%llu", i_size); 312 313 nr_pages = (i_size + PAGE_SIZE - 1) / PAGE_SIZE; 314 315 req->actual_len = i_size; /* May change */ 316 req->len = nr_pages * PAGE_SIZE; /* We can ask for more than there is */ 317 req->data_version = dvnode->status.data_version; /* May change */ 318 iov_iter_xarray(&req->def_iter, READ, &dvnode->vfs_inode.i_mapping->i_pages, 319 0, i_size); 320 req->iter = &req->def_iter; 321 322 /* Fill in any gaps that we might find where the memory reclaimer has 323 * been at work and pin all the pages. If there are any gaps, we will 324 * need to reread the entire directory contents. 325 */ 326 i = req->nr_pages; 327 while (i < nr_pages) { 328 struct page *pages[8], *page; 329 330 n = find_get_pages_contig(dvnode->vfs_inode.i_mapping, i, 331 min_t(unsigned int, nr_pages - i, 332 ARRAY_SIZE(pages)), 333 pages); 334 _debug("find %u at %u/%u", n, i, nr_pages); 335 336 if (n == 0) { 337 gfp_t gfp = dvnode->vfs_inode.i_mapping->gfp_mask; 338 339 if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) 340 afs_stat_v(dvnode, n_inval); 341 342 ret = -ENOMEM; 343 page = __page_cache_alloc(gfp); 344 if (!page) 345 goto error; 346 ret = add_to_page_cache_lru(page, 347 dvnode->vfs_inode.i_mapping, 348 i, gfp); 349 if (ret < 0) 350 goto error; 351 352 attach_page_private(page, (void *)1); 353 unlock_page(page); 354 req->nr_pages++; 355 i++; 356 } else { 357 req->nr_pages += n; 358 i += n; 359 } 360 } 361 362 /* If we're going to reload, we need to lock all the pages to prevent 363 * races. 364 */ 365 ret = -ERESTARTSYS; 366 if (down_read_killable(&dvnode->validate_lock) < 0) 367 goto error; 368 369 if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) 370 goto success; 371 372 up_read(&dvnode->validate_lock); 373 if (down_write_killable(&dvnode->validate_lock) < 0) 374 goto error; 375 376 if (!test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) { 377 trace_afs_reload_dir(dvnode); 378 ret = afs_fetch_data(dvnode, req); 379 if (ret < 0) 380 goto error_unlock; 381 382 task_io_account_read(PAGE_SIZE * req->nr_pages); 383 384 if (req->len < req->file_size) { 385 /* The content has grown, so we need to expand the 386 * buffer. 387 */ 388 up_write(&dvnode->validate_lock); 389 goto expand; 390 } 391 392 /* Validate the data we just read. */ 393 ret = afs_dir_check(dvnode, req); 394 if (ret < 0) 395 goto error_unlock; 396 397 // TODO: Trim excess pages 398 399 set_bit(AFS_VNODE_DIR_VALID, &dvnode->flags); 400 } 401 402 downgrade_write(&dvnode->validate_lock); 403 success: 404 return req; 405 406 error_unlock: 407 up_write(&dvnode->validate_lock); 408 error: 409 afs_put_read(req); 410 _leave(" = %d", ret); 411 return ERR_PTR(ret); 412 } 413 414 /* 415 * deal with one block in an AFS directory 416 */ 417 static int afs_dir_iterate_block(struct afs_vnode *dvnode, 418 struct dir_context *ctx, 419 union afs_xdr_dir_block *block, 420 unsigned blkoff) 421 { 422 union afs_xdr_dirent *dire; 423 unsigned offset, next, curr, nr_slots; 424 size_t nlen; 425 int tmp; 426 427 _enter("%u,%x,%p,,",(unsigned)ctx->pos,blkoff,block); 428 429 curr = (ctx->pos - blkoff) / sizeof(union afs_xdr_dirent); 430 431 /* walk through the block, an entry at a time */ 432 for (offset = (blkoff == 0 ? AFS_DIR_RESV_BLOCKS0 : AFS_DIR_RESV_BLOCKS); 433 offset < AFS_DIR_SLOTS_PER_BLOCK; 434 offset = next 435 ) { 436 /* skip entries marked unused in the bitmap */ 437 if (!(block->hdr.bitmap[offset / 8] & 438 (1 << (offset % 8)))) { 439 _debug("ENT[%zu.%u]: unused", 440 blkoff / sizeof(union afs_xdr_dir_block), offset); 441 next = offset + 1; 442 if (offset >= curr) 443 ctx->pos = blkoff + 444 next * sizeof(union afs_xdr_dirent); 445 continue; 446 } 447 448 /* got a valid entry */ 449 dire = &block->dirents[offset]; 450 nlen = strnlen(dire->u.name, 451 sizeof(*block) - 452 offset * sizeof(union afs_xdr_dirent)); 453 if (nlen > AFSNAMEMAX - 1) { 454 _debug("ENT[%zu]: name too long (len %u/%zu)", 455 blkoff / sizeof(union afs_xdr_dir_block), 456 offset, nlen); 457 return afs_bad(dvnode, afs_file_error_dir_name_too_long); 458 } 459 460 _debug("ENT[%zu.%u]: %s %zu \"%s\"", 461 blkoff / sizeof(union afs_xdr_dir_block), offset, 462 (offset < curr ? "skip" : "fill"), 463 nlen, dire->u.name); 464 465 nr_slots = afs_dir_calc_slots(nlen); 466 next = offset + nr_slots; 467 if (next > AFS_DIR_SLOTS_PER_BLOCK) { 468 _debug("ENT[%zu.%u]:" 469 " %u extends beyond end dir block" 470 " (len %zu)", 471 blkoff / sizeof(union afs_xdr_dir_block), 472 offset, next, nlen); 473 return afs_bad(dvnode, afs_file_error_dir_over_end); 474 } 475 476 /* Check that the name-extension dirents are all allocated */ 477 for (tmp = 1; tmp < nr_slots; tmp++) { 478 unsigned int ix = offset + tmp; 479 if (!(block->hdr.bitmap[ix / 8] & (1 << (ix % 8)))) { 480 _debug("ENT[%zu.u]:" 481 " %u unmarked extension (%u/%u)", 482 blkoff / sizeof(union afs_xdr_dir_block), 483 offset, tmp, nr_slots); 484 return afs_bad(dvnode, afs_file_error_dir_unmarked_ext); 485 } 486 } 487 488 /* skip if starts before the current position */ 489 if (offset < curr) 490 continue; 491 492 /* found the next entry */ 493 if (!dir_emit(ctx, dire->u.name, nlen, 494 ntohl(dire->u.vnode), 495 (ctx->actor == afs_lookup_filldir || 496 ctx->actor == afs_lookup_one_filldir)? 497 ntohl(dire->u.unique) : DT_UNKNOWN)) { 498 _leave(" = 0 [full]"); 499 return 0; 500 } 501 502 ctx->pos = blkoff + next * sizeof(union afs_xdr_dirent); 503 } 504 505 _leave(" = 1 [more]"); 506 return 1; 507 } 508 509 /* 510 * iterate through the data blob that lists the contents of an AFS directory 511 */ 512 static int afs_dir_iterate(struct inode *dir, struct dir_context *ctx, 513 struct key *key, afs_dataversion_t *_dir_version) 514 { 515 struct afs_vnode *dvnode = AFS_FS_I(dir); 516 struct afs_xdr_dir_page *dbuf; 517 union afs_xdr_dir_block *dblock; 518 struct afs_read *req; 519 struct page *page; 520 unsigned blkoff, limit; 521 void __rcu **slot; 522 int ret; 523 524 _enter("{%lu},%u,,", dir->i_ino, (unsigned)ctx->pos); 525 526 if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dir)->flags)) { 527 _leave(" = -ESTALE"); 528 return -ESTALE; 529 } 530 531 req = afs_read_dir(dvnode, key); 532 if (IS_ERR(req)) 533 return PTR_ERR(req); 534 *_dir_version = req->data_version; 535 536 /* round the file position up to the next entry boundary */ 537 ctx->pos += sizeof(union afs_xdr_dirent) - 1; 538 ctx->pos &= ~(sizeof(union afs_xdr_dirent) - 1); 539 540 /* walk through the blocks in sequence */ 541 ret = 0; 542 while (ctx->pos < req->actual_len) { 543 blkoff = ctx->pos & ~(sizeof(union afs_xdr_dir_block) - 1); 544 545 /* Fetch the appropriate page from the directory and re-add it 546 * to the LRU. We have all the pages pinned with an extra ref. 547 */ 548 rcu_read_lock(); 549 page = NULL; 550 slot = radix_tree_lookup_slot(&dvnode->vfs_inode.i_mapping->i_pages, 551 blkoff / PAGE_SIZE); 552 if (slot) 553 page = radix_tree_deref_slot(slot); 554 rcu_read_unlock(); 555 if (!page) { 556 ret = afs_bad(dvnode, afs_file_error_dir_missing_page); 557 break; 558 } 559 mark_page_accessed(page); 560 561 limit = blkoff & ~(PAGE_SIZE - 1); 562 563 dbuf = kmap(page); 564 565 /* deal with the individual blocks stashed on this page */ 566 do { 567 dblock = &dbuf->blocks[(blkoff % PAGE_SIZE) / 568 sizeof(union afs_xdr_dir_block)]; 569 ret = afs_dir_iterate_block(dvnode, ctx, dblock, blkoff); 570 if (ret != 1) { 571 kunmap(page); 572 goto out; 573 } 574 575 blkoff += sizeof(union afs_xdr_dir_block); 576 577 } while (ctx->pos < dir->i_size && blkoff < limit); 578 579 kunmap(page); 580 ret = 0; 581 } 582 583 out: 584 up_read(&dvnode->validate_lock); 585 afs_put_read(req); 586 _leave(" = %d", ret); 587 return ret; 588 } 589 590 /* 591 * read an AFS directory 592 */ 593 static int afs_readdir(struct file *file, struct dir_context *ctx) 594 { 595 afs_dataversion_t dir_version; 596 597 return afs_dir_iterate(file_inode(file), ctx, afs_file_key(file), 598 &dir_version); 599 } 600 601 /* 602 * Search the directory for a single name 603 * - if afs_dir_iterate_block() spots this function, it'll pass the FID 604 * uniquifier through dtype 605 */ 606 static int afs_lookup_one_filldir(struct dir_context *ctx, const char *name, 607 int nlen, loff_t fpos, u64 ino, unsigned dtype) 608 { 609 struct afs_lookup_one_cookie *cookie = 610 container_of(ctx, struct afs_lookup_one_cookie, ctx); 611 612 _enter("{%s,%u},%s,%u,,%llu,%u", 613 cookie->name.name, cookie->name.len, name, nlen, 614 (unsigned long long) ino, dtype); 615 616 /* insanity checks first */ 617 BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048); 618 BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32); 619 620 if (cookie->name.len != nlen || 621 memcmp(cookie->name.name, name, nlen) != 0) { 622 _leave(" = 0 [no]"); 623 return 0; 624 } 625 626 cookie->fid.vnode = ino; 627 cookie->fid.unique = dtype; 628 cookie->found = 1; 629 630 _leave(" = -1 [found]"); 631 return -1; 632 } 633 634 /* 635 * Do a lookup of a single name in a directory 636 * - just returns the FID the dentry name maps to if found 637 */ 638 static int afs_do_lookup_one(struct inode *dir, struct dentry *dentry, 639 struct afs_fid *fid, struct key *key, 640 afs_dataversion_t *_dir_version) 641 { 642 struct afs_super_info *as = dir->i_sb->s_fs_info; 643 struct afs_lookup_one_cookie cookie = { 644 .ctx.actor = afs_lookup_one_filldir, 645 .name = dentry->d_name, 646 .fid.vid = as->volume->vid 647 }; 648 int ret; 649 650 _enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry); 651 652 /* search the directory */ 653 ret = afs_dir_iterate(dir, &cookie.ctx, key, _dir_version); 654 if (ret < 0) { 655 _leave(" = %d [iter]", ret); 656 return ret; 657 } 658 659 if (!cookie.found) { 660 _leave(" = -ENOENT [not found]"); 661 return -ENOENT; 662 } 663 664 *fid = cookie.fid; 665 _leave(" = 0 { vn=%llu u=%u }", fid->vnode, fid->unique); 666 return 0; 667 } 668 669 /* 670 * search the directory for a name 671 * - if afs_dir_iterate_block() spots this function, it'll pass the FID 672 * uniquifier through dtype 673 */ 674 static int afs_lookup_filldir(struct dir_context *ctx, const char *name, 675 int nlen, loff_t fpos, u64 ino, unsigned dtype) 676 { 677 struct afs_lookup_cookie *cookie = 678 container_of(ctx, struct afs_lookup_cookie, ctx); 679 int ret; 680 681 _enter("{%s,%u},%s,%u,,%llu,%u", 682 cookie->name.name, cookie->name.len, name, nlen, 683 (unsigned long long) ino, dtype); 684 685 /* insanity checks first */ 686 BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048); 687 BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32); 688 689 if (cookie->found) { 690 if (cookie->nr_fids < 50) { 691 cookie->fids[cookie->nr_fids].vnode = ino; 692 cookie->fids[cookie->nr_fids].unique = dtype; 693 cookie->nr_fids++; 694 } 695 } else if (cookie->name.len == nlen && 696 memcmp(cookie->name.name, name, nlen) == 0) { 697 cookie->fids[1].vnode = ino; 698 cookie->fids[1].unique = dtype; 699 cookie->found = 1; 700 if (cookie->one_only) 701 return -1; 702 } 703 704 ret = cookie->nr_fids >= 50 ? -1 : 0; 705 _leave(" = %d", ret); 706 return ret; 707 } 708 709 /* 710 * Deal with the result of a successful lookup operation. Turn all the files 711 * into inodes and save the first one - which is the one we actually want. 712 */ 713 static void afs_do_lookup_success(struct afs_operation *op) 714 { 715 struct afs_vnode_param *vp; 716 struct afs_vnode *vnode; 717 struct inode *inode; 718 u32 abort_code; 719 int i; 720 721 _enter(""); 722 723 for (i = 0; i < op->nr_files; i++) { 724 switch (i) { 725 case 0: 726 vp = &op->file[0]; 727 abort_code = vp->scb.status.abort_code; 728 if (abort_code != 0) { 729 op->ac.abort_code = abort_code; 730 op->error = afs_abort_to_error(abort_code); 731 } 732 break; 733 734 case 1: 735 vp = &op->file[1]; 736 break; 737 738 default: 739 vp = &op->more_files[i - 2]; 740 break; 741 } 742 743 if (!vp->scb.have_status && !vp->scb.have_error) 744 continue; 745 746 _debug("do [%u]", i); 747 if (vp->vnode) { 748 if (!test_bit(AFS_VNODE_UNSET, &vp->vnode->flags)) 749 afs_vnode_commit_status(op, vp); 750 } else if (vp->scb.status.abort_code == 0) { 751 inode = afs_iget(op, vp); 752 if (!IS_ERR(inode)) { 753 vnode = AFS_FS_I(inode); 754 afs_cache_permit(vnode, op->key, 755 0 /* Assume vnode->cb_break is 0 */ + 756 op->cb_v_break, 757 &vp->scb); 758 vp->vnode = vnode; 759 vp->put_vnode = true; 760 } 761 } else { 762 _debug("- abort %d %llx:%llx.%x", 763 vp->scb.status.abort_code, 764 vp->fid.vid, vp->fid.vnode, vp->fid.unique); 765 } 766 } 767 768 _leave(""); 769 } 770 771 static const struct afs_operation_ops afs_inline_bulk_status_operation = { 772 .issue_afs_rpc = afs_fs_inline_bulk_status, 773 .issue_yfs_rpc = yfs_fs_inline_bulk_status, 774 .success = afs_do_lookup_success, 775 }; 776 777 static const struct afs_operation_ops afs_lookup_fetch_status_operation = { 778 .issue_afs_rpc = afs_fs_fetch_status, 779 .issue_yfs_rpc = yfs_fs_fetch_status, 780 .success = afs_do_lookup_success, 781 .aborted = afs_check_for_remote_deletion, 782 }; 783 784 /* 785 * See if we know that the server we expect to use doesn't support 786 * FS.InlineBulkStatus. 787 */ 788 static bool afs_server_supports_ibulk(struct afs_vnode *dvnode) 789 { 790 struct afs_server_list *slist; 791 struct afs_volume *volume = dvnode->volume; 792 struct afs_server *server; 793 bool ret = true; 794 int i; 795 796 if (!test_bit(AFS_VOLUME_MAYBE_NO_IBULK, &volume->flags)) 797 return true; 798 799 rcu_read_lock(); 800 slist = rcu_dereference(volume->servers); 801 802 for (i = 0; i < slist->nr_servers; i++) { 803 server = slist->servers[i].server; 804 if (server == dvnode->cb_server) { 805 if (test_bit(AFS_SERVER_FL_NO_IBULK, &server->flags)) 806 ret = false; 807 break; 808 } 809 } 810 811 rcu_read_unlock(); 812 return ret; 813 } 814 815 /* 816 * Do a lookup in a directory. We make use of bulk lookup to query a slew of 817 * files in one go and create inodes for them. The inode of the file we were 818 * asked for is returned. 819 */ 820 static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry, 821 struct key *key) 822 { 823 struct afs_lookup_cookie *cookie; 824 struct afs_vnode_param *vp; 825 struct afs_operation *op; 826 struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode; 827 struct inode *inode = NULL, *ti; 828 afs_dataversion_t data_version = READ_ONCE(dvnode->status.data_version); 829 long ret; 830 int i; 831 832 _enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry); 833 834 cookie = kzalloc(sizeof(struct afs_lookup_cookie), GFP_KERNEL); 835 if (!cookie) 836 return ERR_PTR(-ENOMEM); 837 838 for (i = 0; i < ARRAY_SIZE(cookie->fids); i++) 839 cookie->fids[i].vid = dvnode->fid.vid; 840 cookie->ctx.actor = afs_lookup_filldir; 841 cookie->name = dentry->d_name; 842 cookie->nr_fids = 2; /* slot 0 is saved for the fid we actually want 843 * and slot 1 for the directory */ 844 845 if (!afs_server_supports_ibulk(dvnode)) 846 cookie->one_only = true; 847 848 /* search the directory */ 849 ret = afs_dir_iterate(dir, &cookie->ctx, key, &data_version); 850 if (ret < 0) 851 goto out; 852 853 dentry->d_fsdata = (void *)(unsigned long)data_version; 854 855 ret = -ENOENT; 856 if (!cookie->found) 857 goto out; 858 859 /* Check to see if we already have an inode for the primary fid. */ 860 inode = ilookup5(dir->i_sb, cookie->fids[1].vnode, 861 afs_ilookup5_test_by_fid, &cookie->fids[1]); 862 if (inode) 863 goto out; /* We do */ 864 865 /* Okay, we didn't find it. We need to query the server - and whilst 866 * we're doing that, we're going to attempt to look up a bunch of other 867 * vnodes also. 868 */ 869 op = afs_alloc_operation(NULL, dvnode->volume); 870 if (IS_ERR(op)) { 871 ret = PTR_ERR(op); 872 goto out; 873 } 874 875 afs_op_set_vnode(op, 0, dvnode); 876 afs_op_set_fid(op, 1, &cookie->fids[1]); 877 878 op->nr_files = cookie->nr_fids; 879 _debug("nr_files %u", op->nr_files); 880 881 /* Need space for examining all the selected files */ 882 op->error = -ENOMEM; 883 if (op->nr_files > 2) { 884 op->more_files = kvcalloc(op->nr_files - 2, 885 sizeof(struct afs_vnode_param), 886 GFP_KERNEL); 887 if (!op->more_files) 888 goto out_op; 889 890 for (i = 2; i < op->nr_files; i++) { 891 vp = &op->more_files[i - 2]; 892 vp->fid = cookie->fids[i]; 893 894 /* Find any inodes that already exist and get their 895 * callback counters. 896 */ 897 ti = ilookup5_nowait(dir->i_sb, vp->fid.vnode, 898 afs_ilookup5_test_by_fid, &vp->fid); 899 if (!IS_ERR_OR_NULL(ti)) { 900 vnode = AFS_FS_I(ti); 901 vp->dv_before = vnode->status.data_version; 902 vp->cb_break_before = afs_calc_vnode_cb_break(vnode); 903 vp->vnode = vnode; 904 vp->put_vnode = true; 905 vp->speculative = true; /* vnode not locked */ 906 } 907 } 908 } 909 910 /* Try FS.InlineBulkStatus first. Abort codes for the individual 911 * lookups contained therein are stored in the reply without aborting 912 * the whole operation. 913 */ 914 op->error = -ENOTSUPP; 915 if (!cookie->one_only) { 916 op->ops = &afs_inline_bulk_status_operation; 917 afs_begin_vnode_operation(op); 918 afs_wait_for_operation(op); 919 } 920 921 if (op->error == -ENOTSUPP) { 922 /* We could try FS.BulkStatus next, but this aborts the entire 923 * op if any of the lookups fails - so, for the moment, revert 924 * to FS.FetchStatus for op->file[1]. 925 */ 926 op->fetch_status.which = 1; 927 op->ops = &afs_lookup_fetch_status_operation; 928 afs_begin_vnode_operation(op); 929 afs_wait_for_operation(op); 930 } 931 inode = ERR_PTR(op->error); 932 933 out_op: 934 if (op->error == 0) { 935 inode = &op->file[1].vnode->vfs_inode; 936 op->file[1].vnode = NULL; 937 } 938 939 if (op->file[0].scb.have_status) 940 dentry->d_fsdata = (void *)(unsigned long)op->file[0].scb.status.data_version; 941 else 942 dentry->d_fsdata = (void *)(unsigned long)op->file[0].dv_before; 943 ret = afs_put_operation(op); 944 out: 945 kfree(cookie); 946 _leave(""); 947 return inode ?: ERR_PTR(ret); 948 } 949 950 /* 951 * Look up an entry in a directory with @sys substitution. 952 */ 953 static struct dentry *afs_lookup_atsys(struct inode *dir, struct dentry *dentry, 954 struct key *key) 955 { 956 struct afs_sysnames *subs; 957 struct afs_net *net = afs_i2net(dir); 958 struct dentry *ret; 959 char *buf, *p, *name; 960 int len, i; 961 962 _enter(""); 963 964 ret = ERR_PTR(-ENOMEM); 965 p = buf = kmalloc(AFSNAMEMAX, GFP_KERNEL); 966 if (!buf) 967 goto out_p; 968 if (dentry->d_name.len > 4) { 969 memcpy(p, dentry->d_name.name, dentry->d_name.len - 4); 970 p += dentry->d_name.len - 4; 971 } 972 973 /* There is an ordered list of substitutes that we have to try. */ 974 read_lock(&net->sysnames_lock); 975 subs = net->sysnames; 976 refcount_inc(&subs->usage); 977 read_unlock(&net->sysnames_lock); 978 979 for (i = 0; i < subs->nr; i++) { 980 name = subs->subs[i]; 981 len = dentry->d_name.len - 4 + strlen(name); 982 if (len >= AFSNAMEMAX) { 983 ret = ERR_PTR(-ENAMETOOLONG); 984 goto out_s; 985 } 986 987 strcpy(p, name); 988 ret = lookup_one_len(buf, dentry->d_parent, len); 989 if (IS_ERR(ret) || d_is_positive(ret)) 990 goto out_s; 991 dput(ret); 992 } 993 994 /* We don't want to d_add() the @sys dentry here as we don't want to 995 * the cached dentry to hide changes to the sysnames list. 996 */ 997 ret = NULL; 998 out_s: 999 afs_put_sysnames(subs); 1000 kfree(buf); 1001 out_p: 1002 key_put(key); 1003 return ret; 1004 } 1005 1006 /* 1007 * look up an entry in a directory 1008 */ 1009 static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry, 1010 unsigned int flags) 1011 { 1012 struct afs_vnode *dvnode = AFS_FS_I(dir); 1013 struct afs_fid fid = {}; 1014 struct inode *inode; 1015 struct dentry *d; 1016 struct key *key; 1017 int ret; 1018 1019 _enter("{%llx:%llu},%p{%pd},", 1020 dvnode->fid.vid, dvnode->fid.vnode, dentry, dentry); 1021 1022 ASSERTCMP(d_inode(dentry), ==, NULL); 1023 1024 if (dentry->d_name.len >= AFSNAMEMAX) { 1025 _leave(" = -ENAMETOOLONG"); 1026 return ERR_PTR(-ENAMETOOLONG); 1027 } 1028 1029 if (test_bit(AFS_VNODE_DELETED, &dvnode->flags)) { 1030 _leave(" = -ESTALE"); 1031 return ERR_PTR(-ESTALE); 1032 } 1033 1034 key = afs_request_key(dvnode->volume->cell); 1035 if (IS_ERR(key)) { 1036 _leave(" = %ld [key]", PTR_ERR(key)); 1037 return ERR_CAST(key); 1038 } 1039 1040 ret = afs_validate(dvnode, key); 1041 if (ret < 0) { 1042 key_put(key); 1043 _leave(" = %d [val]", ret); 1044 return ERR_PTR(ret); 1045 } 1046 1047 if (dentry->d_name.len >= 4 && 1048 dentry->d_name.name[dentry->d_name.len - 4] == '@' && 1049 dentry->d_name.name[dentry->d_name.len - 3] == 's' && 1050 dentry->d_name.name[dentry->d_name.len - 2] == 'y' && 1051 dentry->d_name.name[dentry->d_name.len - 1] == 's') 1052 return afs_lookup_atsys(dir, dentry, key); 1053 1054 afs_stat_v(dvnode, n_lookup); 1055 inode = afs_do_lookup(dir, dentry, key); 1056 key_put(key); 1057 if (inode == ERR_PTR(-ENOENT)) 1058 inode = afs_try_auto_mntpt(dentry, dir); 1059 1060 if (!IS_ERR_OR_NULL(inode)) 1061 fid = AFS_FS_I(inode)->fid; 1062 1063 _debug("splice %p", dentry->d_inode); 1064 d = d_splice_alias(inode, dentry); 1065 if (!IS_ERR_OR_NULL(d)) { 1066 d->d_fsdata = dentry->d_fsdata; 1067 trace_afs_lookup(dvnode, &d->d_name, &fid); 1068 } else { 1069 trace_afs_lookup(dvnode, &dentry->d_name, &fid); 1070 } 1071 _leave(""); 1072 return d; 1073 } 1074 1075 /* 1076 * Check the validity of a dentry under RCU conditions. 1077 */ 1078 static int afs_d_revalidate_rcu(struct dentry *dentry) 1079 { 1080 struct afs_vnode *dvnode, *vnode; 1081 struct dentry *parent; 1082 struct inode *dir, *inode; 1083 long dir_version, de_version; 1084 1085 _enter("%p", dentry); 1086 1087 /* Check the parent directory is still valid first. */ 1088 parent = READ_ONCE(dentry->d_parent); 1089 dir = d_inode_rcu(parent); 1090 if (!dir) 1091 return -ECHILD; 1092 dvnode = AFS_FS_I(dir); 1093 if (test_bit(AFS_VNODE_DELETED, &dvnode->flags)) 1094 return -ECHILD; 1095 1096 if (!afs_check_validity(dvnode)) 1097 return -ECHILD; 1098 1099 /* We only need to invalidate a dentry if the server's copy changed 1100 * behind our back. If we made the change, it's no problem. Note that 1101 * on a 32-bit system, we only have 32 bits in the dentry to store the 1102 * version. 1103 */ 1104 dir_version = (long)READ_ONCE(dvnode->status.data_version); 1105 de_version = (long)READ_ONCE(dentry->d_fsdata); 1106 if (de_version != dir_version) { 1107 dir_version = (long)READ_ONCE(dvnode->invalid_before); 1108 if (de_version - dir_version < 0) 1109 return -ECHILD; 1110 } 1111 1112 /* Check to see if the vnode referred to by the dentry still 1113 * has a callback. 1114 */ 1115 if (d_really_is_positive(dentry)) { 1116 inode = d_inode_rcu(dentry); 1117 if (inode) { 1118 vnode = AFS_FS_I(inode); 1119 if (!afs_check_validity(vnode)) 1120 return -ECHILD; 1121 } 1122 } 1123 1124 return 1; /* Still valid */ 1125 } 1126 1127 /* 1128 * check that a dentry lookup hit has found a valid entry 1129 * - NOTE! the hit can be a negative hit too, so we can't assume we have an 1130 * inode 1131 */ 1132 static int afs_d_revalidate(struct dentry *dentry, unsigned int flags) 1133 { 1134 struct afs_vnode *vnode, *dir; 1135 struct afs_fid fid; 1136 struct dentry *parent; 1137 struct inode *inode; 1138 struct key *key; 1139 afs_dataversion_t dir_version, invalid_before; 1140 long de_version; 1141 int ret; 1142 1143 if (flags & LOOKUP_RCU) 1144 return afs_d_revalidate_rcu(dentry); 1145 1146 if (d_really_is_positive(dentry)) { 1147 vnode = AFS_FS_I(d_inode(dentry)); 1148 _enter("{v={%llx:%llu} n=%pd fl=%lx},", 1149 vnode->fid.vid, vnode->fid.vnode, dentry, 1150 vnode->flags); 1151 } else { 1152 _enter("{neg n=%pd}", dentry); 1153 } 1154 1155 key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell); 1156 if (IS_ERR(key)) 1157 key = NULL; 1158 1159 if (d_really_is_positive(dentry)) { 1160 inode = d_inode(dentry); 1161 if (inode) { 1162 vnode = AFS_FS_I(inode); 1163 afs_validate(vnode, key); 1164 if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) 1165 goto out_bad; 1166 } 1167 } 1168 1169 /* lock down the parent dentry so we can peer at it */ 1170 parent = dget_parent(dentry); 1171 dir = AFS_FS_I(d_inode(parent)); 1172 1173 /* validate the parent directory */ 1174 afs_validate(dir, key); 1175 1176 if (test_bit(AFS_VNODE_DELETED, &dir->flags)) { 1177 _debug("%pd: parent dir deleted", dentry); 1178 goto out_bad_parent; 1179 } 1180 1181 /* We only need to invalidate a dentry if the server's copy changed 1182 * behind our back. If we made the change, it's no problem. Note that 1183 * on a 32-bit system, we only have 32 bits in the dentry to store the 1184 * version. 1185 */ 1186 dir_version = dir->status.data_version; 1187 de_version = (long)dentry->d_fsdata; 1188 if (de_version == (long)dir_version) 1189 goto out_valid_noupdate; 1190 1191 invalid_before = dir->invalid_before; 1192 if (de_version - (long)invalid_before >= 0) 1193 goto out_valid; 1194 1195 _debug("dir modified"); 1196 afs_stat_v(dir, n_reval); 1197 1198 /* search the directory for this vnode */ 1199 ret = afs_do_lookup_one(&dir->vfs_inode, dentry, &fid, key, &dir_version); 1200 switch (ret) { 1201 case 0: 1202 /* the filename maps to something */ 1203 if (d_really_is_negative(dentry)) 1204 goto out_bad_parent; 1205 inode = d_inode(dentry); 1206 if (is_bad_inode(inode)) { 1207 printk("kAFS: afs_d_revalidate: %pd2 has bad inode\n", 1208 dentry); 1209 goto out_bad_parent; 1210 } 1211 1212 vnode = AFS_FS_I(inode); 1213 1214 /* if the vnode ID has changed, then the dirent points to a 1215 * different file */ 1216 if (fid.vnode != vnode->fid.vnode) { 1217 _debug("%pd: dirent changed [%llu != %llu]", 1218 dentry, fid.vnode, 1219 vnode->fid.vnode); 1220 goto not_found; 1221 } 1222 1223 /* if the vnode ID uniqifier has changed, then the file has 1224 * been deleted and replaced, and the original vnode ID has 1225 * been reused */ 1226 if (fid.unique != vnode->fid.unique) { 1227 _debug("%pd: file deleted (uq %u -> %u I:%u)", 1228 dentry, fid.unique, 1229 vnode->fid.unique, 1230 vnode->vfs_inode.i_generation); 1231 write_seqlock(&vnode->cb_lock); 1232 set_bit(AFS_VNODE_DELETED, &vnode->flags); 1233 write_sequnlock(&vnode->cb_lock); 1234 goto not_found; 1235 } 1236 goto out_valid; 1237 1238 case -ENOENT: 1239 /* the filename is unknown */ 1240 _debug("%pd: dirent not found", dentry); 1241 if (d_really_is_positive(dentry)) 1242 goto not_found; 1243 goto out_valid; 1244 1245 default: 1246 _debug("failed to iterate dir %pd: %d", 1247 parent, ret); 1248 goto out_bad_parent; 1249 } 1250 1251 out_valid: 1252 dentry->d_fsdata = (void *)(unsigned long)dir_version; 1253 out_valid_noupdate: 1254 dput(parent); 1255 key_put(key); 1256 _leave(" = 1 [valid]"); 1257 return 1; 1258 1259 /* the dirent, if it exists, now points to a different vnode */ 1260 not_found: 1261 spin_lock(&dentry->d_lock); 1262 dentry->d_flags |= DCACHE_NFSFS_RENAMED; 1263 spin_unlock(&dentry->d_lock); 1264 1265 out_bad_parent: 1266 _debug("dropping dentry %pd2", dentry); 1267 dput(parent); 1268 out_bad: 1269 key_put(key); 1270 1271 _leave(" = 0 [bad]"); 1272 return 0; 1273 } 1274 1275 /* 1276 * allow the VFS to enquire as to whether a dentry should be unhashed (mustn't 1277 * sleep) 1278 * - called from dput() when d_count is going to 0. 1279 * - return 1 to request dentry be unhashed, 0 otherwise 1280 */ 1281 static int afs_d_delete(const struct dentry *dentry) 1282 { 1283 _enter("%pd", dentry); 1284 1285 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) 1286 goto zap; 1287 1288 if (d_really_is_positive(dentry) && 1289 (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(d_inode(dentry))->flags) || 1290 test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(d_inode(dentry))->flags))) 1291 goto zap; 1292 1293 _leave(" = 0 [keep]"); 1294 return 0; 1295 1296 zap: 1297 _leave(" = 1 [zap]"); 1298 return 1; 1299 } 1300 1301 /* 1302 * Clean up sillyrename files on dentry removal. 1303 */ 1304 static void afs_d_iput(struct dentry *dentry, struct inode *inode) 1305 { 1306 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) 1307 afs_silly_iput(dentry, inode); 1308 iput(inode); 1309 } 1310 1311 /* 1312 * handle dentry release 1313 */ 1314 void afs_d_release(struct dentry *dentry) 1315 { 1316 _enter("%pd", dentry); 1317 } 1318 1319 void afs_check_for_remote_deletion(struct afs_operation *op) 1320 { 1321 struct afs_vnode *vnode = op->file[0].vnode; 1322 1323 switch (op->ac.abort_code) { 1324 case VNOVNODE: 1325 set_bit(AFS_VNODE_DELETED, &vnode->flags); 1326 afs_break_callback(vnode, afs_cb_break_for_deleted); 1327 } 1328 } 1329 1330 /* 1331 * Create a new inode for create/mkdir/symlink 1332 */ 1333 static void afs_vnode_new_inode(struct afs_operation *op) 1334 { 1335 struct afs_vnode_param *vp = &op->file[1]; 1336 struct afs_vnode *vnode; 1337 struct inode *inode; 1338 1339 _enter(""); 1340 1341 ASSERTCMP(op->error, ==, 0); 1342 1343 inode = afs_iget(op, vp); 1344 if (IS_ERR(inode)) { 1345 /* ENOMEM or EINTR at a really inconvenient time - just abandon 1346 * the new directory on the server. 1347 */ 1348 op->error = PTR_ERR(inode); 1349 return; 1350 } 1351 1352 vnode = AFS_FS_I(inode); 1353 set_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags); 1354 if (!op->error) 1355 afs_cache_permit(vnode, op->key, vnode->cb_break, &vp->scb); 1356 d_instantiate(op->dentry, inode); 1357 } 1358 1359 static void afs_create_success(struct afs_operation *op) 1360 { 1361 _enter("op=%08x", op->debug_id); 1362 op->ctime = op->file[0].scb.status.mtime_client; 1363 afs_vnode_commit_status(op, &op->file[0]); 1364 afs_update_dentry_version(op, &op->file[0], op->dentry); 1365 afs_vnode_new_inode(op); 1366 } 1367 1368 static void afs_create_edit_dir(struct afs_operation *op) 1369 { 1370 struct afs_vnode_param *dvp = &op->file[0]; 1371 struct afs_vnode_param *vp = &op->file[1]; 1372 struct afs_vnode *dvnode = dvp->vnode; 1373 1374 _enter("op=%08x", op->debug_id); 1375 1376 down_write(&dvnode->validate_lock); 1377 if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) && 1378 dvnode->status.data_version == dvp->dv_before + dvp->dv_delta) 1379 afs_edit_dir_add(dvnode, &op->dentry->d_name, &vp->fid, 1380 op->create.reason); 1381 up_write(&dvnode->validate_lock); 1382 } 1383 1384 static void afs_create_put(struct afs_operation *op) 1385 { 1386 _enter("op=%08x", op->debug_id); 1387 1388 if (op->error) 1389 d_drop(op->dentry); 1390 } 1391 1392 static const struct afs_operation_ops afs_mkdir_operation = { 1393 .issue_afs_rpc = afs_fs_make_dir, 1394 .issue_yfs_rpc = yfs_fs_make_dir, 1395 .success = afs_create_success, 1396 .aborted = afs_check_for_remote_deletion, 1397 .edit_dir = afs_create_edit_dir, 1398 .put = afs_create_put, 1399 }; 1400 1401 /* 1402 * create a directory on an AFS filesystem 1403 */ 1404 static int afs_mkdir(struct user_namespace *mnt_userns, struct inode *dir, 1405 struct dentry *dentry, umode_t mode) 1406 { 1407 struct afs_operation *op; 1408 struct afs_vnode *dvnode = AFS_FS_I(dir); 1409 1410 _enter("{%llx:%llu},{%pd},%ho", 1411 dvnode->fid.vid, dvnode->fid.vnode, dentry, mode); 1412 1413 op = afs_alloc_operation(NULL, dvnode->volume); 1414 if (IS_ERR(op)) { 1415 d_drop(dentry); 1416 return PTR_ERR(op); 1417 } 1418 1419 afs_op_set_vnode(op, 0, dvnode); 1420 op->file[0].dv_delta = 1; 1421 op->file[0].modification = true; 1422 op->file[0].update_ctime = true; 1423 op->dentry = dentry; 1424 op->create.mode = S_IFDIR | mode; 1425 op->create.reason = afs_edit_dir_for_mkdir; 1426 op->ops = &afs_mkdir_operation; 1427 return afs_do_sync_operation(op); 1428 } 1429 1430 /* 1431 * Remove a subdir from a directory. 1432 */ 1433 static void afs_dir_remove_subdir(struct dentry *dentry) 1434 { 1435 if (d_really_is_positive(dentry)) { 1436 struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry)); 1437 1438 clear_nlink(&vnode->vfs_inode); 1439 set_bit(AFS_VNODE_DELETED, &vnode->flags); 1440 clear_bit(AFS_VNODE_CB_PROMISED, &vnode->flags); 1441 clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags); 1442 } 1443 } 1444 1445 static void afs_rmdir_success(struct afs_operation *op) 1446 { 1447 _enter("op=%08x", op->debug_id); 1448 op->ctime = op->file[0].scb.status.mtime_client; 1449 afs_vnode_commit_status(op, &op->file[0]); 1450 afs_update_dentry_version(op, &op->file[0], op->dentry); 1451 } 1452 1453 static void afs_rmdir_edit_dir(struct afs_operation *op) 1454 { 1455 struct afs_vnode_param *dvp = &op->file[0]; 1456 struct afs_vnode *dvnode = dvp->vnode; 1457 1458 _enter("op=%08x", op->debug_id); 1459 afs_dir_remove_subdir(op->dentry); 1460 1461 down_write(&dvnode->validate_lock); 1462 if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) && 1463 dvnode->status.data_version == dvp->dv_before + dvp->dv_delta) 1464 afs_edit_dir_remove(dvnode, &op->dentry->d_name, 1465 afs_edit_dir_for_rmdir); 1466 up_write(&dvnode->validate_lock); 1467 } 1468 1469 static void afs_rmdir_put(struct afs_operation *op) 1470 { 1471 _enter("op=%08x", op->debug_id); 1472 if (op->file[1].vnode) 1473 up_write(&op->file[1].vnode->rmdir_lock); 1474 } 1475 1476 static const struct afs_operation_ops afs_rmdir_operation = { 1477 .issue_afs_rpc = afs_fs_remove_dir, 1478 .issue_yfs_rpc = yfs_fs_remove_dir, 1479 .success = afs_rmdir_success, 1480 .aborted = afs_check_for_remote_deletion, 1481 .edit_dir = afs_rmdir_edit_dir, 1482 .put = afs_rmdir_put, 1483 }; 1484 1485 /* 1486 * remove a directory from an AFS filesystem 1487 */ 1488 static int afs_rmdir(struct inode *dir, struct dentry *dentry) 1489 { 1490 struct afs_operation *op; 1491 struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode = NULL; 1492 int ret; 1493 1494 _enter("{%llx:%llu},{%pd}", 1495 dvnode->fid.vid, dvnode->fid.vnode, dentry); 1496 1497 op = afs_alloc_operation(NULL, dvnode->volume); 1498 if (IS_ERR(op)) 1499 return PTR_ERR(op); 1500 1501 afs_op_set_vnode(op, 0, dvnode); 1502 op->file[0].dv_delta = 1; 1503 op->file[0].modification = true; 1504 op->file[0].update_ctime = true; 1505 1506 op->dentry = dentry; 1507 op->ops = &afs_rmdir_operation; 1508 1509 /* Try to make sure we have a callback promise on the victim. */ 1510 if (d_really_is_positive(dentry)) { 1511 vnode = AFS_FS_I(d_inode(dentry)); 1512 ret = afs_validate(vnode, op->key); 1513 if (ret < 0) 1514 goto error; 1515 } 1516 1517 if (vnode) { 1518 ret = down_write_killable(&vnode->rmdir_lock); 1519 if (ret < 0) 1520 goto error; 1521 op->file[1].vnode = vnode; 1522 } 1523 1524 return afs_do_sync_operation(op); 1525 1526 error: 1527 return afs_put_operation(op); 1528 } 1529 1530 /* 1531 * Remove a link to a file or symlink from a directory. 1532 * 1533 * If the file was not deleted due to excess hard links, the fileserver will 1534 * break the callback promise on the file - if it had one - before it returns 1535 * to us, and if it was deleted, it won't 1536 * 1537 * However, if we didn't have a callback promise outstanding, or it was 1538 * outstanding on a different server, then it won't break it either... 1539 */ 1540 static void afs_dir_remove_link(struct afs_operation *op) 1541 { 1542 struct afs_vnode *dvnode = op->file[0].vnode; 1543 struct afs_vnode *vnode = op->file[1].vnode; 1544 struct dentry *dentry = op->dentry; 1545 int ret; 1546 1547 if (op->error != 0 || 1548 (op->file[1].scb.have_status && op->file[1].scb.have_error)) 1549 return; 1550 if (d_really_is_positive(dentry)) 1551 return; 1552 1553 if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) { 1554 /* Already done */ 1555 } else if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) { 1556 write_seqlock(&vnode->cb_lock); 1557 drop_nlink(&vnode->vfs_inode); 1558 if (vnode->vfs_inode.i_nlink == 0) { 1559 set_bit(AFS_VNODE_DELETED, &vnode->flags); 1560 __afs_break_callback(vnode, afs_cb_break_for_unlink); 1561 } 1562 write_sequnlock(&vnode->cb_lock); 1563 } else { 1564 afs_break_callback(vnode, afs_cb_break_for_unlink); 1565 1566 if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) 1567 _debug("AFS_VNODE_DELETED"); 1568 1569 ret = afs_validate(vnode, op->key); 1570 if (ret != -ESTALE) 1571 op->error = ret; 1572 } 1573 1574 _debug("nlink %d [val %d]", vnode->vfs_inode.i_nlink, op->error); 1575 } 1576 1577 static void afs_unlink_success(struct afs_operation *op) 1578 { 1579 _enter("op=%08x", op->debug_id); 1580 op->ctime = op->file[0].scb.status.mtime_client; 1581 afs_check_dir_conflict(op, &op->file[0]); 1582 afs_vnode_commit_status(op, &op->file[0]); 1583 afs_vnode_commit_status(op, &op->file[1]); 1584 afs_update_dentry_version(op, &op->file[0], op->dentry); 1585 afs_dir_remove_link(op); 1586 } 1587 1588 static void afs_unlink_edit_dir(struct afs_operation *op) 1589 { 1590 struct afs_vnode_param *dvp = &op->file[0]; 1591 struct afs_vnode *dvnode = dvp->vnode; 1592 1593 _enter("op=%08x", op->debug_id); 1594 down_write(&dvnode->validate_lock); 1595 if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) && 1596 dvnode->status.data_version == dvp->dv_before + dvp->dv_delta) 1597 afs_edit_dir_remove(dvnode, &op->dentry->d_name, 1598 afs_edit_dir_for_unlink); 1599 up_write(&dvnode->validate_lock); 1600 } 1601 1602 static void afs_unlink_put(struct afs_operation *op) 1603 { 1604 _enter("op=%08x", op->debug_id); 1605 if (op->unlink.need_rehash && op->error < 0 && op->error != -ENOENT) 1606 d_rehash(op->dentry); 1607 } 1608 1609 static const struct afs_operation_ops afs_unlink_operation = { 1610 .issue_afs_rpc = afs_fs_remove_file, 1611 .issue_yfs_rpc = yfs_fs_remove_file, 1612 .success = afs_unlink_success, 1613 .aborted = afs_check_for_remote_deletion, 1614 .edit_dir = afs_unlink_edit_dir, 1615 .put = afs_unlink_put, 1616 }; 1617 1618 /* 1619 * Remove a file or symlink from an AFS filesystem. 1620 */ 1621 static int afs_unlink(struct inode *dir, struct dentry *dentry) 1622 { 1623 struct afs_operation *op; 1624 struct afs_vnode *dvnode = AFS_FS_I(dir); 1625 struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry)); 1626 int ret; 1627 1628 _enter("{%llx:%llu},{%pd}", 1629 dvnode->fid.vid, dvnode->fid.vnode, dentry); 1630 1631 if (dentry->d_name.len >= AFSNAMEMAX) 1632 return -ENAMETOOLONG; 1633 1634 op = afs_alloc_operation(NULL, dvnode->volume); 1635 if (IS_ERR(op)) 1636 return PTR_ERR(op); 1637 1638 afs_op_set_vnode(op, 0, dvnode); 1639 op->file[0].dv_delta = 1; 1640 op->file[0].modification = true; 1641 op->file[0].update_ctime = true; 1642 1643 /* Try to make sure we have a callback promise on the victim. */ 1644 ret = afs_validate(vnode, op->key); 1645 if (ret < 0) { 1646 op->error = ret; 1647 goto error; 1648 } 1649 1650 spin_lock(&dentry->d_lock); 1651 if (d_count(dentry) > 1) { 1652 spin_unlock(&dentry->d_lock); 1653 /* Start asynchronous writeout of the inode */ 1654 write_inode_now(d_inode(dentry), 0); 1655 op->error = afs_sillyrename(dvnode, vnode, dentry, op->key); 1656 goto error; 1657 } 1658 if (!d_unhashed(dentry)) { 1659 /* Prevent a race with RCU lookup. */ 1660 __d_drop(dentry); 1661 op->unlink.need_rehash = true; 1662 } 1663 spin_unlock(&dentry->d_lock); 1664 1665 op->file[1].vnode = vnode; 1666 op->file[1].update_ctime = true; 1667 op->file[1].op_unlinked = true; 1668 op->dentry = dentry; 1669 op->ops = &afs_unlink_operation; 1670 afs_begin_vnode_operation(op); 1671 afs_wait_for_operation(op); 1672 1673 /* If there was a conflict with a third party, check the status of the 1674 * unlinked vnode. 1675 */ 1676 if (op->error == 0 && (op->flags & AFS_OPERATION_DIR_CONFLICT)) { 1677 op->file[1].update_ctime = false; 1678 op->fetch_status.which = 1; 1679 op->ops = &afs_fetch_status_operation; 1680 afs_begin_vnode_operation(op); 1681 afs_wait_for_operation(op); 1682 } 1683 1684 return afs_put_operation(op); 1685 1686 error: 1687 return afs_put_operation(op); 1688 } 1689 1690 static const struct afs_operation_ops afs_create_operation = { 1691 .issue_afs_rpc = afs_fs_create_file, 1692 .issue_yfs_rpc = yfs_fs_create_file, 1693 .success = afs_create_success, 1694 .aborted = afs_check_for_remote_deletion, 1695 .edit_dir = afs_create_edit_dir, 1696 .put = afs_create_put, 1697 }; 1698 1699 /* 1700 * create a regular file on an AFS filesystem 1701 */ 1702 static int afs_create(struct user_namespace *mnt_userns, struct inode *dir, 1703 struct dentry *dentry, umode_t mode, bool excl) 1704 { 1705 struct afs_operation *op; 1706 struct afs_vnode *dvnode = AFS_FS_I(dir); 1707 int ret = -ENAMETOOLONG; 1708 1709 _enter("{%llx:%llu},{%pd},%ho", 1710 dvnode->fid.vid, dvnode->fid.vnode, dentry, mode); 1711 1712 if (dentry->d_name.len >= AFSNAMEMAX) 1713 goto error; 1714 1715 op = afs_alloc_operation(NULL, dvnode->volume); 1716 if (IS_ERR(op)) { 1717 ret = PTR_ERR(op); 1718 goto error; 1719 } 1720 1721 afs_op_set_vnode(op, 0, dvnode); 1722 op->file[0].dv_delta = 1; 1723 op->file[0].modification = true; 1724 op->file[0].update_ctime = true; 1725 1726 op->dentry = dentry; 1727 op->create.mode = S_IFREG | mode; 1728 op->create.reason = afs_edit_dir_for_create; 1729 op->ops = &afs_create_operation; 1730 return afs_do_sync_operation(op); 1731 1732 error: 1733 d_drop(dentry); 1734 _leave(" = %d", ret); 1735 return ret; 1736 } 1737 1738 static void afs_link_success(struct afs_operation *op) 1739 { 1740 struct afs_vnode_param *dvp = &op->file[0]; 1741 struct afs_vnode_param *vp = &op->file[1]; 1742 1743 _enter("op=%08x", op->debug_id); 1744 op->ctime = dvp->scb.status.mtime_client; 1745 afs_vnode_commit_status(op, dvp); 1746 afs_vnode_commit_status(op, vp); 1747 afs_update_dentry_version(op, dvp, op->dentry); 1748 if (op->dentry_2->d_parent == op->dentry->d_parent) 1749 afs_update_dentry_version(op, dvp, op->dentry_2); 1750 ihold(&vp->vnode->vfs_inode); 1751 d_instantiate(op->dentry, &vp->vnode->vfs_inode); 1752 } 1753 1754 static void afs_link_put(struct afs_operation *op) 1755 { 1756 _enter("op=%08x", op->debug_id); 1757 if (op->error) 1758 d_drop(op->dentry); 1759 } 1760 1761 static const struct afs_operation_ops afs_link_operation = { 1762 .issue_afs_rpc = afs_fs_link, 1763 .issue_yfs_rpc = yfs_fs_link, 1764 .success = afs_link_success, 1765 .aborted = afs_check_for_remote_deletion, 1766 .edit_dir = afs_create_edit_dir, 1767 .put = afs_link_put, 1768 }; 1769 1770 /* 1771 * create a hard link between files in an AFS filesystem 1772 */ 1773 static int afs_link(struct dentry *from, struct inode *dir, 1774 struct dentry *dentry) 1775 { 1776 struct afs_operation *op; 1777 struct afs_vnode *dvnode = AFS_FS_I(dir); 1778 struct afs_vnode *vnode = AFS_FS_I(d_inode(from)); 1779 int ret = -ENAMETOOLONG; 1780 1781 _enter("{%llx:%llu},{%llx:%llu},{%pd}", 1782 vnode->fid.vid, vnode->fid.vnode, 1783 dvnode->fid.vid, dvnode->fid.vnode, 1784 dentry); 1785 1786 if (dentry->d_name.len >= AFSNAMEMAX) 1787 goto error; 1788 1789 op = afs_alloc_operation(NULL, dvnode->volume); 1790 if (IS_ERR(op)) { 1791 ret = PTR_ERR(op); 1792 goto error; 1793 } 1794 1795 afs_op_set_vnode(op, 0, dvnode); 1796 afs_op_set_vnode(op, 1, vnode); 1797 op->file[0].dv_delta = 1; 1798 op->file[0].modification = true; 1799 op->file[0].update_ctime = true; 1800 op->file[1].update_ctime = true; 1801 1802 op->dentry = dentry; 1803 op->dentry_2 = from; 1804 op->ops = &afs_link_operation; 1805 op->create.reason = afs_edit_dir_for_link; 1806 return afs_do_sync_operation(op); 1807 1808 error: 1809 d_drop(dentry); 1810 _leave(" = %d", ret); 1811 return ret; 1812 } 1813 1814 static const struct afs_operation_ops afs_symlink_operation = { 1815 .issue_afs_rpc = afs_fs_symlink, 1816 .issue_yfs_rpc = yfs_fs_symlink, 1817 .success = afs_create_success, 1818 .aborted = afs_check_for_remote_deletion, 1819 .edit_dir = afs_create_edit_dir, 1820 .put = afs_create_put, 1821 }; 1822 1823 /* 1824 * create a symlink in an AFS filesystem 1825 */ 1826 static int afs_symlink(struct user_namespace *mnt_userns, struct inode *dir, 1827 struct dentry *dentry, const char *content) 1828 { 1829 struct afs_operation *op; 1830 struct afs_vnode *dvnode = AFS_FS_I(dir); 1831 int ret; 1832 1833 _enter("{%llx:%llu},{%pd},%s", 1834 dvnode->fid.vid, dvnode->fid.vnode, dentry, 1835 content); 1836 1837 ret = -ENAMETOOLONG; 1838 if (dentry->d_name.len >= AFSNAMEMAX) 1839 goto error; 1840 1841 ret = -EINVAL; 1842 if (strlen(content) >= AFSPATHMAX) 1843 goto error; 1844 1845 op = afs_alloc_operation(NULL, dvnode->volume); 1846 if (IS_ERR(op)) { 1847 ret = PTR_ERR(op); 1848 goto error; 1849 } 1850 1851 afs_op_set_vnode(op, 0, dvnode); 1852 op->file[0].dv_delta = 1; 1853 1854 op->dentry = dentry; 1855 op->ops = &afs_symlink_operation; 1856 op->create.reason = afs_edit_dir_for_symlink; 1857 op->create.symlink = content; 1858 return afs_do_sync_operation(op); 1859 1860 error: 1861 d_drop(dentry); 1862 _leave(" = %d", ret); 1863 return ret; 1864 } 1865 1866 static void afs_rename_success(struct afs_operation *op) 1867 { 1868 _enter("op=%08x", op->debug_id); 1869 1870 op->ctime = op->file[0].scb.status.mtime_client; 1871 afs_check_dir_conflict(op, &op->file[1]); 1872 afs_vnode_commit_status(op, &op->file[0]); 1873 if (op->file[1].vnode != op->file[0].vnode) { 1874 op->ctime = op->file[1].scb.status.mtime_client; 1875 afs_vnode_commit_status(op, &op->file[1]); 1876 } 1877 } 1878 1879 static void afs_rename_edit_dir(struct afs_operation *op) 1880 { 1881 struct afs_vnode_param *orig_dvp = &op->file[0]; 1882 struct afs_vnode_param *new_dvp = &op->file[1]; 1883 struct afs_vnode *orig_dvnode = orig_dvp->vnode; 1884 struct afs_vnode *new_dvnode = new_dvp->vnode; 1885 struct afs_vnode *vnode = AFS_FS_I(d_inode(op->dentry)); 1886 struct dentry *old_dentry = op->dentry; 1887 struct dentry *new_dentry = op->dentry_2; 1888 struct inode *new_inode; 1889 1890 _enter("op=%08x", op->debug_id); 1891 1892 if (op->rename.rehash) { 1893 d_rehash(op->rename.rehash); 1894 op->rename.rehash = NULL; 1895 } 1896 1897 down_write(&orig_dvnode->validate_lock); 1898 if (test_bit(AFS_VNODE_DIR_VALID, &orig_dvnode->flags) && 1899 orig_dvnode->status.data_version == orig_dvp->dv_before + orig_dvp->dv_delta) 1900 afs_edit_dir_remove(orig_dvnode, &old_dentry->d_name, 1901 afs_edit_dir_for_rename_0); 1902 1903 if (new_dvnode != orig_dvnode) { 1904 up_write(&orig_dvnode->validate_lock); 1905 down_write(&new_dvnode->validate_lock); 1906 } 1907 1908 if (test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags) && 1909 new_dvnode->status.data_version == new_dvp->dv_before + new_dvp->dv_delta) { 1910 if (!op->rename.new_negative) 1911 afs_edit_dir_remove(new_dvnode, &new_dentry->d_name, 1912 afs_edit_dir_for_rename_1); 1913 1914 afs_edit_dir_add(new_dvnode, &new_dentry->d_name, 1915 &vnode->fid, afs_edit_dir_for_rename_2); 1916 } 1917 1918 new_inode = d_inode(new_dentry); 1919 if (new_inode) { 1920 spin_lock(&new_inode->i_lock); 1921 if (S_ISDIR(new_inode->i_mode)) 1922 clear_nlink(new_inode); 1923 else if (new_inode->i_nlink > 0) 1924 drop_nlink(new_inode); 1925 spin_unlock(&new_inode->i_lock); 1926 } 1927 1928 /* Now we can update d_fsdata on the dentries to reflect their 1929 * new parent's data_version. 1930 * 1931 * Note that if we ever implement RENAME_EXCHANGE, we'll have 1932 * to update both dentries with opposing dir versions. 1933 */ 1934 afs_update_dentry_version(op, new_dvp, op->dentry); 1935 afs_update_dentry_version(op, new_dvp, op->dentry_2); 1936 1937 d_move(old_dentry, new_dentry); 1938 1939 up_write(&new_dvnode->validate_lock); 1940 } 1941 1942 static void afs_rename_put(struct afs_operation *op) 1943 { 1944 _enter("op=%08x", op->debug_id); 1945 if (op->rename.rehash) 1946 d_rehash(op->rename.rehash); 1947 dput(op->rename.tmp); 1948 if (op->error) 1949 d_rehash(op->dentry); 1950 } 1951 1952 static const struct afs_operation_ops afs_rename_operation = { 1953 .issue_afs_rpc = afs_fs_rename, 1954 .issue_yfs_rpc = yfs_fs_rename, 1955 .success = afs_rename_success, 1956 .edit_dir = afs_rename_edit_dir, 1957 .put = afs_rename_put, 1958 }; 1959 1960 /* 1961 * rename a file in an AFS filesystem and/or move it between directories 1962 */ 1963 static int afs_rename(struct user_namespace *mnt_userns, struct inode *old_dir, 1964 struct dentry *old_dentry, struct inode *new_dir, 1965 struct dentry *new_dentry, unsigned int flags) 1966 { 1967 struct afs_operation *op; 1968 struct afs_vnode *orig_dvnode, *new_dvnode, *vnode; 1969 int ret; 1970 1971 if (flags) 1972 return -EINVAL; 1973 1974 /* Don't allow silly-rename files be moved around. */ 1975 if (old_dentry->d_flags & DCACHE_NFSFS_RENAMED) 1976 return -EINVAL; 1977 1978 vnode = AFS_FS_I(d_inode(old_dentry)); 1979 orig_dvnode = AFS_FS_I(old_dir); 1980 new_dvnode = AFS_FS_I(new_dir); 1981 1982 _enter("{%llx:%llu},{%llx:%llu},{%llx:%llu},{%pd}", 1983 orig_dvnode->fid.vid, orig_dvnode->fid.vnode, 1984 vnode->fid.vid, vnode->fid.vnode, 1985 new_dvnode->fid.vid, new_dvnode->fid.vnode, 1986 new_dentry); 1987 1988 op = afs_alloc_operation(NULL, orig_dvnode->volume); 1989 if (IS_ERR(op)) 1990 return PTR_ERR(op); 1991 1992 afs_op_set_vnode(op, 0, orig_dvnode); 1993 afs_op_set_vnode(op, 1, new_dvnode); /* May be same as orig_dvnode */ 1994 op->file[0].dv_delta = 1; 1995 op->file[1].dv_delta = 1; 1996 op->file[0].modification = true; 1997 op->file[1].modification = true; 1998 op->file[0].update_ctime = true; 1999 op->file[1].update_ctime = true; 2000 2001 op->dentry = old_dentry; 2002 op->dentry_2 = new_dentry; 2003 op->rename.new_negative = d_is_negative(new_dentry); 2004 op->ops = &afs_rename_operation; 2005 2006 /* For non-directories, check whether the target is busy and if so, 2007 * make a copy of the dentry and then do a silly-rename. If the 2008 * silly-rename succeeds, the copied dentry is hashed and becomes the 2009 * new target. 2010 */ 2011 if (d_is_positive(new_dentry) && !d_is_dir(new_dentry)) { 2012 /* To prevent any new references to the target during the 2013 * rename, we unhash the dentry in advance. 2014 */ 2015 if (!d_unhashed(new_dentry)) { 2016 d_drop(new_dentry); 2017 op->rename.rehash = new_dentry; 2018 } 2019 2020 if (d_count(new_dentry) > 2) { 2021 /* copy the target dentry's name */ 2022 op->rename.tmp = d_alloc(new_dentry->d_parent, 2023 &new_dentry->d_name); 2024 if (!op->rename.tmp) { 2025 op->error = -ENOMEM; 2026 goto error; 2027 } 2028 2029 ret = afs_sillyrename(new_dvnode, 2030 AFS_FS_I(d_inode(new_dentry)), 2031 new_dentry, op->key); 2032 if (ret) { 2033 op->error = ret; 2034 goto error; 2035 } 2036 2037 op->dentry_2 = op->rename.tmp; 2038 op->rename.rehash = NULL; 2039 op->rename.new_negative = true; 2040 } 2041 } 2042 2043 /* This bit is potentially nasty as there's a potential race with 2044 * afs_d_revalidate{,_rcu}(). We have to change d_fsdata on the dentry 2045 * to reflect it's new parent's new data_version after the op, but 2046 * d_revalidate may see old_dentry between the op having taken place 2047 * and the version being updated. 2048 * 2049 * So drop the old_dentry for now to make other threads go through 2050 * lookup instead - which we hold a lock against. 2051 */ 2052 d_drop(old_dentry); 2053 2054 return afs_do_sync_operation(op); 2055 2056 error: 2057 return afs_put_operation(op); 2058 } 2059 2060 /* 2061 * Release a directory page and clean up its private state if it's not busy 2062 * - return true if the page can now be released, false if not 2063 */ 2064 static int afs_dir_releasepage(struct page *page, gfp_t gfp_flags) 2065 { 2066 struct afs_vnode *dvnode = AFS_FS_I(page->mapping->host); 2067 2068 _enter("{{%llx:%llu}[%lu]}", dvnode->fid.vid, dvnode->fid.vnode, page->index); 2069 2070 detach_page_private(page); 2071 2072 /* The directory will need reloading. */ 2073 if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) 2074 afs_stat_v(dvnode, n_relpg); 2075 return 1; 2076 } 2077 2078 /* 2079 * invalidate part or all of a page 2080 * - release a page and clean up its private data if offset is 0 (indicating 2081 * the entire page) 2082 */ 2083 static void afs_dir_invalidatepage(struct page *page, unsigned int offset, 2084 unsigned int length) 2085 { 2086 struct afs_vnode *dvnode = AFS_FS_I(page->mapping->host); 2087 2088 _enter("{%lu},%u,%u", page->index, offset, length); 2089 2090 BUG_ON(!PageLocked(page)); 2091 2092 /* The directory will need reloading. */ 2093 if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) 2094 afs_stat_v(dvnode, n_inval); 2095 2096 /* we clean up only if the entire page is being invalidated */ 2097 if (offset == 0 && length == thp_size(page)) 2098 detach_page_private(page); 2099 } 2100