1 #include <linux/ceph/ceph_debug.h> 2 3 #include <linux/spinlock.h> 4 #include <linux/fs_struct.h> 5 #include <linux/namei.h> 6 #include <linux/slab.h> 7 #include <linux/sched.h> 8 9 #include "super.h" 10 #include "mds_client.h" 11 12 /* 13 * Directory operations: readdir, lookup, create, link, unlink, 14 * rename, etc. 15 */ 16 17 /* 18 * Ceph MDS operations are specified in terms of a base ino and 19 * relative path. Thus, the client can specify an operation on a 20 * specific inode (e.g., a getattr due to fstat(2)), or as a path 21 * relative to, say, the root directory. 22 * 23 * Normally, we limit ourselves to strict inode ops (no path component) 24 * or dentry operations (a single path component relative to an ino). The 25 * exception to this is open_root_dentry(), which will open the mount 26 * point by name. 27 */ 28 29 const struct inode_operations ceph_dir_iops; 30 const struct file_operations ceph_dir_fops; 31 const struct dentry_operations ceph_dentry_ops; 32 33 /* 34 * Initialize ceph dentry state. 35 */ 36 int ceph_init_dentry(struct dentry *dentry) 37 { 38 struct ceph_dentry_info *di; 39 40 if (dentry->d_fsdata) 41 return 0; 42 43 if (ceph_snap(dentry->d_parent->d_inode) == CEPH_NOSNAP) 44 dentry->d_op = &ceph_dentry_ops; 45 else if (ceph_snap(dentry->d_parent->d_inode) == CEPH_SNAPDIR) 46 dentry->d_op = &ceph_snapdir_dentry_ops; 47 else 48 dentry->d_op = &ceph_snap_dentry_ops; 49 50 di = kmem_cache_alloc(ceph_dentry_cachep, GFP_NOFS | __GFP_ZERO); 51 if (!di) 52 return -ENOMEM; /* oh well */ 53 54 spin_lock(&dentry->d_lock); 55 if (dentry->d_fsdata) { 56 /* lost a race */ 57 kmem_cache_free(ceph_dentry_cachep, di); 58 goto out_unlock; 59 } 60 di->dentry = dentry; 61 di->lease_session = NULL; 62 dentry->d_fsdata = di; 63 dentry->d_time = jiffies; 64 ceph_dentry_lru_add(dentry); 65 out_unlock: 66 spin_unlock(&dentry->d_lock); 67 return 0; 68 } 69 70 71 72 /* 73 * for readdir, we encode the directory frag and offset within that 74 * frag into f_pos. 75 */ 76 static unsigned fpos_frag(loff_t p) 77 { 78 return p >> 32; 79 } 80 static unsigned fpos_off(loff_t p) 81 { 82 return p & 0xffffffff; 83 } 84 85 /* 86 * When possible, we try to satisfy a readdir by peeking at the 87 * dcache. We make this work by carefully ordering dentries on 88 * d_u.d_child when we initially get results back from the MDS, and 89 * falling back to a "normal" sync readdir if any dentries in the dir 90 * are dropped. 91 * 92 * I_COMPLETE tells indicates we have all dentries in the dir. It is 93 * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by 94 * the MDS if/when the directory is modified). 95 */ 96 static int __dcache_readdir(struct file *filp, 97 void *dirent, filldir_t filldir) 98 { 99 struct ceph_file_info *fi = filp->private_data; 100 struct dentry *parent = filp->f_dentry; 101 struct inode *dir = parent->d_inode; 102 struct list_head *p; 103 struct dentry *dentry, *last; 104 struct ceph_dentry_info *di; 105 int err = 0; 106 107 /* claim ref on last dentry we returned */ 108 last = fi->dentry; 109 fi->dentry = NULL; 110 111 dout("__dcache_readdir %p at %llu (last %p)\n", dir, filp->f_pos, 112 last); 113 114 spin_lock(&dcache_lock); 115 116 /* start at beginning? */ 117 if (filp->f_pos == 2 || (last && 118 filp->f_pos < ceph_dentry(last)->offset)) { 119 if (list_empty(&parent->d_subdirs)) 120 goto out_unlock; 121 p = parent->d_subdirs.prev; 122 dout(" initial p %p/%p\n", p->prev, p->next); 123 } else { 124 p = last->d_u.d_child.prev; 125 } 126 127 more: 128 dentry = list_entry(p, struct dentry, d_u.d_child); 129 di = ceph_dentry(dentry); 130 while (1) { 131 dout(" p %p/%p %s d_subdirs %p/%p\n", p->prev, p->next, 132 d_unhashed(dentry) ? "!hashed" : "hashed", 133 parent->d_subdirs.prev, parent->d_subdirs.next); 134 if (p == &parent->d_subdirs) { 135 fi->at_end = 1; 136 goto out_unlock; 137 } 138 if (!d_unhashed(dentry) && dentry->d_inode && 139 ceph_snap(dentry->d_inode) != CEPH_SNAPDIR && 140 ceph_ino(dentry->d_inode) != CEPH_INO_CEPH && 141 filp->f_pos <= di->offset) 142 break; 143 dout(" skipping %p %.*s at %llu (%llu)%s%s\n", dentry, 144 dentry->d_name.len, dentry->d_name.name, di->offset, 145 filp->f_pos, d_unhashed(dentry) ? " unhashed" : "", 146 !dentry->d_inode ? " null" : ""); 147 p = p->prev; 148 dentry = list_entry(p, struct dentry, d_u.d_child); 149 di = ceph_dentry(dentry); 150 } 151 152 atomic_inc(&dentry->d_count); 153 spin_unlock(&dcache_lock); 154 155 dout(" %llu (%llu) dentry %p %.*s %p\n", di->offset, filp->f_pos, 156 dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode); 157 filp->f_pos = di->offset; 158 err = filldir(dirent, dentry->d_name.name, 159 dentry->d_name.len, di->offset, 160 dentry->d_inode->i_ino, 161 dentry->d_inode->i_mode >> 12); 162 163 if (last) { 164 if (err < 0) { 165 /* remember our position */ 166 fi->dentry = last; 167 fi->next_offset = di->offset; 168 } else { 169 dput(last); 170 } 171 } 172 last = dentry; 173 174 if (err < 0) 175 goto out; 176 177 filp->f_pos++; 178 179 /* make sure a dentry wasn't dropped while we didn't have dcache_lock */ 180 if (!ceph_i_test(dir, CEPH_I_COMPLETE)) { 181 dout(" lost I_COMPLETE on %p; falling back to mds\n", dir); 182 err = -EAGAIN; 183 goto out; 184 } 185 186 spin_lock(&dcache_lock); 187 p = p->prev; /* advance to next dentry */ 188 goto more; 189 190 out_unlock: 191 spin_unlock(&dcache_lock); 192 out: 193 if (last) 194 dput(last); 195 return err; 196 } 197 198 /* 199 * make note of the last dentry we read, so we can 200 * continue at the same lexicographical point, 201 * regardless of what dir changes take place on the 202 * server. 203 */ 204 static int note_last_dentry(struct ceph_file_info *fi, const char *name, 205 int len) 206 { 207 kfree(fi->last_name); 208 fi->last_name = kmalloc(len+1, GFP_NOFS); 209 if (!fi->last_name) 210 return -ENOMEM; 211 memcpy(fi->last_name, name, len); 212 fi->last_name[len] = 0; 213 dout("note_last_dentry '%s'\n", fi->last_name); 214 return 0; 215 } 216 217 static int ceph_readdir(struct file *filp, void *dirent, filldir_t filldir) 218 { 219 struct ceph_file_info *fi = filp->private_data; 220 struct inode *inode = filp->f_dentry->d_inode; 221 struct ceph_inode_info *ci = ceph_inode(inode); 222 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 223 struct ceph_mds_client *mdsc = fsc->mdsc; 224 unsigned frag = fpos_frag(filp->f_pos); 225 int off = fpos_off(filp->f_pos); 226 int err; 227 u32 ftype; 228 struct ceph_mds_reply_info_parsed *rinfo; 229 const int max_entries = fsc->mount_options->max_readdir; 230 const int max_bytes = fsc->mount_options->max_readdir_bytes; 231 232 dout("readdir %p filp %p frag %u off %u\n", inode, filp, frag, off); 233 if (fi->at_end) 234 return 0; 235 236 /* always start with . and .. */ 237 if (filp->f_pos == 0) { 238 /* note dir version at start of readdir so we can tell 239 * if any dentries get dropped */ 240 fi->dir_release_count = ci->i_release_count; 241 242 dout("readdir off 0 -> '.'\n"); 243 if (filldir(dirent, ".", 1, ceph_make_fpos(0, 0), 244 inode->i_ino, inode->i_mode >> 12) < 0) 245 return 0; 246 filp->f_pos = 1; 247 off = 1; 248 } 249 if (filp->f_pos == 1) { 250 dout("readdir off 1 -> '..'\n"); 251 if (filldir(dirent, "..", 2, ceph_make_fpos(0, 1), 252 filp->f_dentry->d_parent->d_inode->i_ino, 253 inode->i_mode >> 12) < 0) 254 return 0; 255 filp->f_pos = 2; 256 off = 2; 257 } 258 259 /* can we use the dcache? */ 260 spin_lock(&inode->i_lock); 261 if ((filp->f_pos == 2 || fi->dentry) && 262 !ceph_test_mount_opt(fsc, NOASYNCREADDIR) && 263 ceph_snap(inode) != CEPH_SNAPDIR && 264 (ci->i_ceph_flags & CEPH_I_COMPLETE) && 265 __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) { 266 spin_unlock(&inode->i_lock); 267 err = __dcache_readdir(filp, dirent, filldir); 268 if (err != -EAGAIN) 269 return err; 270 } else { 271 spin_unlock(&inode->i_lock); 272 } 273 if (fi->dentry) { 274 err = note_last_dentry(fi, fi->dentry->d_name.name, 275 fi->dentry->d_name.len); 276 if (err) 277 return err; 278 dput(fi->dentry); 279 fi->dentry = NULL; 280 } 281 282 /* proceed with a normal readdir */ 283 284 more: 285 /* do we have the correct frag content buffered? */ 286 if (fi->frag != frag || fi->last_readdir == NULL) { 287 struct ceph_mds_request *req; 288 int op = ceph_snap(inode) == CEPH_SNAPDIR ? 289 CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR; 290 291 /* discard old result, if any */ 292 if (fi->last_readdir) { 293 ceph_mdsc_put_request(fi->last_readdir); 294 fi->last_readdir = NULL; 295 } 296 297 /* requery frag tree, as the frag topology may have changed */ 298 frag = ceph_choose_frag(ceph_inode(inode), frag, NULL, NULL); 299 300 dout("readdir fetching %llx.%llx frag %x offset '%s'\n", 301 ceph_vinop(inode), frag, fi->last_name); 302 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS); 303 if (IS_ERR(req)) 304 return PTR_ERR(req); 305 req->r_inode = igrab(inode); 306 req->r_dentry = dget(filp->f_dentry); 307 /* hints to request -> mds selection code */ 308 req->r_direct_mode = USE_AUTH_MDS; 309 req->r_direct_hash = ceph_frag_value(frag); 310 req->r_direct_is_hash = true; 311 req->r_path2 = kstrdup(fi->last_name, GFP_NOFS); 312 req->r_readdir_offset = fi->next_offset; 313 req->r_args.readdir.frag = cpu_to_le32(frag); 314 req->r_args.readdir.max_entries = cpu_to_le32(max_entries); 315 req->r_args.readdir.max_bytes = cpu_to_le32(max_bytes); 316 req->r_num_caps = max_entries + 1; 317 err = ceph_mdsc_do_request(mdsc, NULL, req); 318 if (err < 0) { 319 ceph_mdsc_put_request(req); 320 return err; 321 } 322 dout("readdir got and parsed readdir result=%d" 323 " on frag %x, end=%d, complete=%d\n", err, frag, 324 (int)req->r_reply_info.dir_end, 325 (int)req->r_reply_info.dir_complete); 326 327 if (!req->r_did_prepopulate) { 328 dout("readdir !did_prepopulate"); 329 fi->dir_release_count--; /* preclude I_COMPLETE */ 330 } 331 332 /* note next offset and last dentry name */ 333 fi->offset = fi->next_offset; 334 fi->last_readdir = req; 335 336 if (req->r_reply_info.dir_end) { 337 kfree(fi->last_name); 338 fi->last_name = NULL; 339 fi->next_offset = 2; 340 } else { 341 rinfo = &req->r_reply_info; 342 err = note_last_dentry(fi, 343 rinfo->dir_dname[rinfo->dir_nr-1], 344 rinfo->dir_dname_len[rinfo->dir_nr-1]); 345 if (err) 346 return err; 347 fi->next_offset += rinfo->dir_nr; 348 } 349 } 350 351 rinfo = &fi->last_readdir->r_reply_info; 352 dout("readdir frag %x num %d off %d chunkoff %d\n", frag, 353 rinfo->dir_nr, off, fi->offset); 354 while (off - fi->offset >= 0 && off - fi->offset < rinfo->dir_nr) { 355 u64 pos = ceph_make_fpos(frag, off); 356 struct ceph_mds_reply_inode *in = 357 rinfo->dir_in[off - fi->offset].in; 358 dout("readdir off %d (%d/%d) -> %lld '%.*s' %p\n", 359 off, off - fi->offset, rinfo->dir_nr, pos, 360 rinfo->dir_dname_len[off - fi->offset], 361 rinfo->dir_dname[off - fi->offset], in); 362 BUG_ON(!in); 363 ftype = le32_to_cpu(in->mode) >> 12; 364 if (filldir(dirent, 365 rinfo->dir_dname[off - fi->offset], 366 rinfo->dir_dname_len[off - fi->offset], 367 pos, 368 le64_to_cpu(in->ino), 369 ftype) < 0) { 370 dout("filldir stopping us...\n"); 371 return 0; 372 } 373 off++; 374 filp->f_pos = pos + 1; 375 } 376 377 if (fi->last_name) { 378 ceph_mdsc_put_request(fi->last_readdir); 379 fi->last_readdir = NULL; 380 goto more; 381 } 382 383 /* more frags? */ 384 if (!ceph_frag_is_rightmost(frag)) { 385 frag = ceph_frag_next(frag); 386 off = 0; 387 filp->f_pos = ceph_make_fpos(frag, off); 388 dout("readdir next frag is %x\n", frag); 389 goto more; 390 } 391 fi->at_end = 1; 392 393 /* 394 * if dir_release_count still matches the dir, no dentries 395 * were released during the whole readdir, and we should have 396 * the complete dir contents in our cache. 397 */ 398 spin_lock(&inode->i_lock); 399 if (ci->i_release_count == fi->dir_release_count) { 400 dout(" marking %p complete\n", inode); 401 ci->i_ceph_flags |= CEPH_I_COMPLETE; 402 ci->i_max_offset = filp->f_pos; 403 } 404 spin_unlock(&inode->i_lock); 405 406 dout("readdir %p filp %p done.\n", inode, filp); 407 return 0; 408 } 409 410 static void reset_readdir(struct ceph_file_info *fi) 411 { 412 if (fi->last_readdir) { 413 ceph_mdsc_put_request(fi->last_readdir); 414 fi->last_readdir = NULL; 415 } 416 kfree(fi->last_name); 417 fi->next_offset = 2; /* compensate for . and .. */ 418 if (fi->dentry) { 419 dput(fi->dentry); 420 fi->dentry = NULL; 421 } 422 fi->at_end = 0; 423 } 424 425 static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int origin) 426 { 427 struct ceph_file_info *fi = file->private_data; 428 struct inode *inode = file->f_mapping->host; 429 loff_t old_offset = offset; 430 loff_t retval; 431 432 mutex_lock(&inode->i_mutex); 433 switch (origin) { 434 case SEEK_END: 435 offset += inode->i_size + 2; /* FIXME */ 436 break; 437 case SEEK_CUR: 438 offset += file->f_pos; 439 } 440 retval = -EINVAL; 441 if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) { 442 if (offset != file->f_pos) { 443 file->f_pos = offset; 444 file->f_version = 0; 445 fi->at_end = 0; 446 } 447 retval = offset; 448 449 /* 450 * discard buffered readdir content on seekdir(0), or 451 * seek to new frag, or seek prior to current chunk. 452 */ 453 if (offset == 0 || 454 fpos_frag(offset) != fpos_frag(old_offset) || 455 fpos_off(offset) < fi->offset) { 456 dout("dir_llseek dropping %p content\n", file); 457 reset_readdir(fi); 458 } 459 460 /* bump dir_release_count if we did a forward seek */ 461 if (offset > old_offset) 462 fi->dir_release_count--; 463 } 464 mutex_unlock(&inode->i_mutex); 465 return retval; 466 } 467 468 /* 469 * Process result of a lookup/open request. 470 * 471 * Mainly, make sure we return the final req->r_dentry (if it already 472 * existed) in place of the original VFS-provided dentry when they 473 * differ. 474 * 475 * Gracefully handle the case where the MDS replies with -ENOENT and 476 * no trace (which it may do, at its discretion, e.g., if it doesn't 477 * care to issue a lease on the negative dentry). 478 */ 479 struct dentry *ceph_finish_lookup(struct ceph_mds_request *req, 480 struct dentry *dentry, int err) 481 { 482 struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb); 483 struct inode *parent = dentry->d_parent->d_inode; 484 485 /* .snap dir? */ 486 if (err == -ENOENT && 487 strcmp(dentry->d_name.name, 488 fsc->mount_options->snapdir_name) == 0) { 489 struct inode *inode = ceph_get_snapdir(parent); 490 dout("ENOENT on snapdir %p '%.*s', linking to snapdir %p\n", 491 dentry, dentry->d_name.len, dentry->d_name.name, inode); 492 BUG_ON(!d_unhashed(dentry)); 493 d_add(dentry, inode); 494 err = 0; 495 } 496 497 if (err == -ENOENT) { 498 /* no trace? */ 499 err = 0; 500 if (!req->r_reply_info.head->is_dentry) { 501 dout("ENOENT and no trace, dentry %p inode %p\n", 502 dentry, dentry->d_inode); 503 if (dentry->d_inode) { 504 d_drop(dentry); 505 err = -ENOENT; 506 } else { 507 d_add(dentry, NULL); 508 } 509 } 510 } 511 if (err) 512 dentry = ERR_PTR(err); 513 else if (dentry != req->r_dentry) 514 dentry = dget(req->r_dentry); /* we got spliced */ 515 else 516 dentry = NULL; 517 return dentry; 518 } 519 520 static int is_root_ceph_dentry(struct inode *inode, struct dentry *dentry) 521 { 522 return ceph_ino(inode) == CEPH_INO_ROOT && 523 strncmp(dentry->d_name.name, ".ceph", 5) == 0; 524 } 525 526 /* 527 * Look up a single dir entry. If there is a lookup intent, inform 528 * the MDS so that it gets our 'caps wanted' value in a single op. 529 */ 530 static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry, 531 struct nameidata *nd) 532 { 533 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); 534 struct ceph_mds_client *mdsc = fsc->mdsc; 535 struct ceph_mds_request *req; 536 int op; 537 int err; 538 539 dout("lookup %p dentry %p '%.*s'\n", 540 dir, dentry, dentry->d_name.len, dentry->d_name.name); 541 542 if (dentry->d_name.len > NAME_MAX) 543 return ERR_PTR(-ENAMETOOLONG); 544 545 err = ceph_init_dentry(dentry); 546 if (err < 0) 547 return ERR_PTR(err); 548 549 /* open (but not create!) intent? */ 550 if (nd && 551 (nd->flags & LOOKUP_OPEN) && 552 (nd->flags & LOOKUP_CONTINUE) == 0 && /* only open last component */ 553 !(nd->intent.open.flags & O_CREAT)) { 554 int mode = nd->intent.open.create_mode & ~current->fs->umask; 555 return ceph_lookup_open(dir, dentry, nd, mode, 1); 556 } 557 558 /* can we conclude ENOENT locally? */ 559 if (dentry->d_inode == NULL) { 560 struct ceph_inode_info *ci = ceph_inode(dir); 561 struct ceph_dentry_info *di = ceph_dentry(dentry); 562 563 spin_lock(&dir->i_lock); 564 dout(" dir %p flags are %d\n", dir, ci->i_ceph_flags); 565 if (strncmp(dentry->d_name.name, 566 fsc->mount_options->snapdir_name, 567 dentry->d_name.len) && 568 !is_root_ceph_dentry(dir, dentry) && 569 (ci->i_ceph_flags & CEPH_I_COMPLETE) && 570 (__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1))) { 571 spin_unlock(&dir->i_lock); 572 dout(" dir %p complete, -ENOENT\n", dir); 573 d_add(dentry, NULL); 574 di->lease_shared_gen = ci->i_shared_gen; 575 return NULL; 576 } 577 spin_unlock(&dir->i_lock); 578 } 579 580 op = ceph_snap(dir) == CEPH_SNAPDIR ? 581 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP; 582 req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS); 583 if (IS_ERR(req)) 584 return ERR_CAST(req); 585 req->r_dentry = dget(dentry); 586 req->r_num_caps = 2; 587 /* we only need inode linkage */ 588 req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE); 589 req->r_locked_dir = dir; 590 err = ceph_mdsc_do_request(mdsc, NULL, req); 591 dentry = ceph_finish_lookup(req, dentry, err); 592 ceph_mdsc_put_request(req); /* will dput(dentry) */ 593 dout("lookup result=%p\n", dentry); 594 return dentry; 595 } 596 597 /* 598 * If we do a create but get no trace back from the MDS, follow up with 599 * a lookup (the VFS expects us to link up the provided dentry). 600 */ 601 int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry) 602 { 603 struct dentry *result = ceph_lookup(dir, dentry, NULL); 604 605 if (result && !IS_ERR(result)) { 606 /* 607 * We created the item, then did a lookup, and found 608 * it was already linked to another inode we already 609 * had in our cache (and thus got spliced). Link our 610 * dentry to that inode, but don't hash it, just in 611 * case the VFS wants to dereference it. 612 */ 613 BUG_ON(!result->d_inode); 614 d_instantiate(dentry, result->d_inode); 615 return 0; 616 } 617 return PTR_ERR(result); 618 } 619 620 static int ceph_mknod(struct inode *dir, struct dentry *dentry, 621 int mode, dev_t rdev) 622 { 623 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); 624 struct ceph_mds_client *mdsc = fsc->mdsc; 625 struct ceph_mds_request *req; 626 int err; 627 628 if (ceph_snap(dir) != CEPH_NOSNAP) 629 return -EROFS; 630 631 dout("mknod in dir %p dentry %p mode 0%o rdev %d\n", 632 dir, dentry, mode, rdev); 633 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS); 634 if (IS_ERR(req)) { 635 d_drop(dentry); 636 return PTR_ERR(req); 637 } 638 req->r_dentry = dget(dentry); 639 req->r_num_caps = 2; 640 req->r_locked_dir = dir; 641 req->r_args.mknod.mode = cpu_to_le32(mode); 642 req->r_args.mknod.rdev = cpu_to_le32(rdev); 643 req->r_dentry_drop = CEPH_CAP_FILE_SHARED; 644 req->r_dentry_unless = CEPH_CAP_FILE_EXCL; 645 err = ceph_mdsc_do_request(mdsc, dir, req); 646 if (!err && !req->r_reply_info.head->is_dentry) 647 err = ceph_handle_notrace_create(dir, dentry); 648 ceph_mdsc_put_request(req); 649 if (err) 650 d_drop(dentry); 651 return err; 652 } 653 654 static int ceph_create(struct inode *dir, struct dentry *dentry, int mode, 655 struct nameidata *nd) 656 { 657 dout("create in dir %p dentry %p name '%.*s'\n", 658 dir, dentry, dentry->d_name.len, dentry->d_name.name); 659 660 if (ceph_snap(dir) != CEPH_NOSNAP) 661 return -EROFS; 662 663 if (nd) { 664 BUG_ON((nd->flags & LOOKUP_OPEN) == 0); 665 dentry = ceph_lookup_open(dir, dentry, nd, mode, 0); 666 /* hrm, what should i do here if we get aliased? */ 667 if (IS_ERR(dentry)) 668 return PTR_ERR(dentry); 669 return 0; 670 } 671 672 /* fall back to mknod */ 673 return ceph_mknod(dir, dentry, (mode & ~S_IFMT) | S_IFREG, 0); 674 } 675 676 static int ceph_symlink(struct inode *dir, struct dentry *dentry, 677 const char *dest) 678 { 679 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); 680 struct ceph_mds_client *mdsc = fsc->mdsc; 681 struct ceph_mds_request *req; 682 int err; 683 684 if (ceph_snap(dir) != CEPH_NOSNAP) 685 return -EROFS; 686 687 dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest); 688 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS); 689 if (IS_ERR(req)) { 690 d_drop(dentry); 691 return PTR_ERR(req); 692 } 693 req->r_dentry = dget(dentry); 694 req->r_num_caps = 2; 695 req->r_path2 = kstrdup(dest, GFP_NOFS); 696 req->r_locked_dir = dir; 697 req->r_dentry_drop = CEPH_CAP_FILE_SHARED; 698 req->r_dentry_unless = CEPH_CAP_FILE_EXCL; 699 err = ceph_mdsc_do_request(mdsc, dir, req); 700 if (!err && !req->r_reply_info.head->is_dentry) 701 err = ceph_handle_notrace_create(dir, dentry); 702 ceph_mdsc_put_request(req); 703 if (err) 704 d_drop(dentry); 705 return err; 706 } 707 708 static int ceph_mkdir(struct inode *dir, struct dentry *dentry, int mode) 709 { 710 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); 711 struct ceph_mds_client *mdsc = fsc->mdsc; 712 struct ceph_mds_request *req; 713 int err = -EROFS; 714 int op; 715 716 if (ceph_snap(dir) == CEPH_SNAPDIR) { 717 /* mkdir .snap/foo is a MKSNAP */ 718 op = CEPH_MDS_OP_MKSNAP; 719 dout("mksnap dir %p snap '%.*s' dn %p\n", dir, 720 dentry->d_name.len, dentry->d_name.name, dentry); 721 } else if (ceph_snap(dir) == CEPH_NOSNAP) { 722 dout("mkdir dir %p dn %p mode 0%o\n", dir, dentry, mode); 723 op = CEPH_MDS_OP_MKDIR; 724 } else { 725 goto out; 726 } 727 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS); 728 if (IS_ERR(req)) { 729 err = PTR_ERR(req); 730 goto out; 731 } 732 733 req->r_dentry = dget(dentry); 734 req->r_num_caps = 2; 735 req->r_locked_dir = dir; 736 req->r_args.mkdir.mode = cpu_to_le32(mode); 737 req->r_dentry_drop = CEPH_CAP_FILE_SHARED; 738 req->r_dentry_unless = CEPH_CAP_FILE_EXCL; 739 err = ceph_mdsc_do_request(mdsc, dir, req); 740 if (!err && !req->r_reply_info.head->is_dentry) 741 err = ceph_handle_notrace_create(dir, dentry); 742 ceph_mdsc_put_request(req); 743 out: 744 if (err < 0) 745 d_drop(dentry); 746 return err; 747 } 748 749 static int ceph_link(struct dentry *old_dentry, struct inode *dir, 750 struct dentry *dentry) 751 { 752 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); 753 struct ceph_mds_client *mdsc = fsc->mdsc; 754 struct ceph_mds_request *req; 755 int err; 756 757 if (ceph_snap(dir) != CEPH_NOSNAP) 758 return -EROFS; 759 760 dout("link in dir %p old_dentry %p dentry %p\n", dir, 761 old_dentry, dentry); 762 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS); 763 if (IS_ERR(req)) { 764 d_drop(dentry); 765 return PTR_ERR(req); 766 } 767 req->r_dentry = dget(dentry); 768 req->r_num_caps = 2; 769 req->r_old_dentry = dget(old_dentry); /* or inode? hrm. */ 770 req->r_locked_dir = dir; 771 req->r_dentry_drop = CEPH_CAP_FILE_SHARED; 772 req->r_dentry_unless = CEPH_CAP_FILE_EXCL; 773 err = ceph_mdsc_do_request(mdsc, dir, req); 774 if (err) 775 d_drop(dentry); 776 else if (!req->r_reply_info.head->is_dentry) 777 d_instantiate(dentry, igrab(old_dentry->d_inode)); 778 ceph_mdsc_put_request(req); 779 return err; 780 } 781 782 /* 783 * For a soon-to-be unlinked file, drop the AUTH_RDCACHE caps. If it 784 * looks like the link count will hit 0, drop any other caps (other 785 * than PIN) we don't specifically want (due to the file still being 786 * open). 787 */ 788 static int drop_caps_for_unlink(struct inode *inode) 789 { 790 struct ceph_inode_info *ci = ceph_inode(inode); 791 int drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL; 792 793 spin_lock(&inode->i_lock); 794 if (inode->i_nlink == 1) { 795 drop |= ~(__ceph_caps_wanted(ci) | CEPH_CAP_PIN); 796 ci->i_ceph_flags |= CEPH_I_NODELAY; 797 } 798 spin_unlock(&inode->i_lock); 799 return drop; 800 } 801 802 /* 803 * rmdir and unlink are differ only by the metadata op code 804 */ 805 static int ceph_unlink(struct inode *dir, struct dentry *dentry) 806 { 807 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); 808 struct ceph_mds_client *mdsc = fsc->mdsc; 809 struct inode *inode = dentry->d_inode; 810 struct ceph_mds_request *req; 811 int err = -EROFS; 812 int op; 813 814 if (ceph_snap(dir) == CEPH_SNAPDIR) { 815 /* rmdir .snap/foo is RMSNAP */ 816 dout("rmsnap dir %p '%.*s' dn %p\n", dir, dentry->d_name.len, 817 dentry->d_name.name, dentry); 818 op = CEPH_MDS_OP_RMSNAP; 819 } else if (ceph_snap(dir) == CEPH_NOSNAP) { 820 dout("unlink/rmdir dir %p dn %p inode %p\n", 821 dir, dentry, inode); 822 op = ((dentry->d_inode->i_mode & S_IFMT) == S_IFDIR) ? 823 CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK; 824 } else 825 goto out; 826 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS); 827 if (IS_ERR(req)) { 828 err = PTR_ERR(req); 829 goto out; 830 } 831 req->r_dentry = dget(dentry); 832 req->r_num_caps = 2; 833 req->r_locked_dir = dir; 834 req->r_dentry_drop = CEPH_CAP_FILE_SHARED; 835 req->r_dentry_unless = CEPH_CAP_FILE_EXCL; 836 req->r_inode_drop = drop_caps_for_unlink(inode); 837 err = ceph_mdsc_do_request(mdsc, dir, req); 838 if (!err && !req->r_reply_info.head->is_dentry) 839 d_delete(dentry); 840 ceph_mdsc_put_request(req); 841 out: 842 return err; 843 } 844 845 static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry, 846 struct inode *new_dir, struct dentry *new_dentry) 847 { 848 struct ceph_fs_client *fsc = ceph_sb_to_client(old_dir->i_sb); 849 struct ceph_mds_client *mdsc = fsc->mdsc; 850 struct ceph_mds_request *req; 851 int err; 852 853 if (ceph_snap(old_dir) != ceph_snap(new_dir)) 854 return -EXDEV; 855 if (ceph_snap(old_dir) != CEPH_NOSNAP || 856 ceph_snap(new_dir) != CEPH_NOSNAP) 857 return -EROFS; 858 dout("rename dir %p dentry %p to dir %p dentry %p\n", 859 old_dir, old_dentry, new_dir, new_dentry); 860 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_RENAME, USE_AUTH_MDS); 861 if (IS_ERR(req)) 862 return PTR_ERR(req); 863 req->r_dentry = dget(new_dentry); 864 req->r_num_caps = 2; 865 req->r_old_dentry = dget(old_dentry); 866 req->r_locked_dir = new_dir; 867 req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED; 868 req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL; 869 req->r_dentry_drop = CEPH_CAP_FILE_SHARED; 870 req->r_dentry_unless = CEPH_CAP_FILE_EXCL; 871 /* release LINK_RDCACHE on source inode (mds will lock it) */ 872 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED; 873 if (new_dentry->d_inode) 874 req->r_inode_drop = drop_caps_for_unlink(new_dentry->d_inode); 875 err = ceph_mdsc_do_request(mdsc, old_dir, req); 876 if (!err && !req->r_reply_info.head->is_dentry) { 877 /* 878 * Normally d_move() is done by fill_trace (called by 879 * do_request, above). If there is no trace, we need 880 * to do it here. 881 */ 882 883 /* d_move screws up d_subdirs order */ 884 ceph_i_clear(new_dir, CEPH_I_COMPLETE); 885 886 d_move(old_dentry, new_dentry); 887 888 /* ensure target dentry is invalidated, despite 889 rehashing bug in vfs_rename_dir */ 890 ceph_invalidate_dentry_lease(new_dentry); 891 } 892 ceph_mdsc_put_request(req); 893 return err; 894 } 895 896 /* 897 * Ensure a dentry lease will no longer revalidate. 898 */ 899 void ceph_invalidate_dentry_lease(struct dentry *dentry) 900 { 901 spin_lock(&dentry->d_lock); 902 dentry->d_time = jiffies; 903 ceph_dentry(dentry)->lease_shared_gen = 0; 904 spin_unlock(&dentry->d_lock); 905 } 906 907 /* 908 * Check if dentry lease is valid. If not, delete the lease. Try to 909 * renew if the least is more than half up. 910 */ 911 static int dentry_lease_is_valid(struct dentry *dentry) 912 { 913 struct ceph_dentry_info *di; 914 struct ceph_mds_session *s; 915 int valid = 0; 916 u32 gen; 917 unsigned long ttl; 918 struct ceph_mds_session *session = NULL; 919 struct inode *dir = NULL; 920 u32 seq = 0; 921 922 spin_lock(&dentry->d_lock); 923 di = ceph_dentry(dentry); 924 if (di && di->lease_session) { 925 s = di->lease_session; 926 spin_lock(&s->s_cap_lock); 927 gen = s->s_cap_gen; 928 ttl = s->s_cap_ttl; 929 spin_unlock(&s->s_cap_lock); 930 931 if (di->lease_gen == gen && 932 time_before(jiffies, dentry->d_time) && 933 time_before(jiffies, ttl)) { 934 valid = 1; 935 if (di->lease_renew_after && 936 time_after(jiffies, di->lease_renew_after)) { 937 /* we should renew */ 938 dir = dentry->d_parent->d_inode; 939 session = ceph_get_mds_session(s); 940 seq = di->lease_seq; 941 di->lease_renew_after = 0; 942 di->lease_renew_from = jiffies; 943 } 944 } 945 } 946 spin_unlock(&dentry->d_lock); 947 948 if (session) { 949 ceph_mdsc_lease_send_msg(session, dir, dentry, 950 CEPH_MDS_LEASE_RENEW, seq); 951 ceph_put_mds_session(session); 952 } 953 dout("dentry_lease_is_valid - dentry %p = %d\n", dentry, valid); 954 return valid; 955 } 956 957 /* 958 * Check if directory-wide content lease/cap is valid. 959 */ 960 static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry) 961 { 962 struct ceph_inode_info *ci = ceph_inode(dir); 963 struct ceph_dentry_info *di = ceph_dentry(dentry); 964 int valid = 0; 965 966 spin_lock(&dir->i_lock); 967 if (ci->i_shared_gen == di->lease_shared_gen) 968 valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1); 969 spin_unlock(&dir->i_lock); 970 dout("dir_lease_is_valid dir %p v%u dentry %p v%u = %d\n", 971 dir, (unsigned)ci->i_shared_gen, dentry, 972 (unsigned)di->lease_shared_gen, valid); 973 return valid; 974 } 975 976 /* 977 * Check if cached dentry can be trusted. 978 */ 979 static int ceph_d_revalidate(struct dentry *dentry, struct nameidata *nd) 980 { 981 struct inode *dir = dentry->d_parent->d_inode; 982 983 dout("d_revalidate %p '%.*s' inode %p offset %lld\n", dentry, 984 dentry->d_name.len, dentry->d_name.name, dentry->d_inode, 985 ceph_dentry(dentry)->offset); 986 987 /* always trust cached snapped dentries, snapdir dentry */ 988 if (ceph_snap(dir) != CEPH_NOSNAP) { 989 dout("d_revalidate %p '%.*s' inode %p is SNAPPED\n", dentry, 990 dentry->d_name.len, dentry->d_name.name, dentry->d_inode); 991 goto out_touch; 992 } 993 if (dentry->d_inode && ceph_snap(dentry->d_inode) == CEPH_SNAPDIR) 994 goto out_touch; 995 996 if (dentry_lease_is_valid(dentry) || 997 dir_lease_is_valid(dir, dentry)) 998 goto out_touch; 999 1000 dout("d_revalidate %p invalid\n", dentry); 1001 d_drop(dentry); 1002 return 0; 1003 out_touch: 1004 ceph_dentry_lru_touch(dentry); 1005 return 1; 1006 } 1007 1008 /* 1009 * When a dentry is released, clear the dir I_COMPLETE if it was part 1010 * of the current dir gen or if this is in the snapshot namespace. 1011 */ 1012 static void ceph_dentry_release(struct dentry *dentry) 1013 { 1014 struct ceph_dentry_info *di = ceph_dentry(dentry); 1015 struct inode *parent_inode = NULL; 1016 u64 snapid = CEPH_NOSNAP; 1017 1018 if (!IS_ROOT(dentry)) { 1019 parent_inode = dentry->d_parent->d_inode; 1020 if (parent_inode) 1021 snapid = ceph_snap(parent_inode); 1022 } 1023 dout("dentry_release %p parent %p\n", dentry, parent_inode); 1024 if (parent_inode && snapid != CEPH_SNAPDIR) { 1025 struct ceph_inode_info *ci = ceph_inode(parent_inode); 1026 1027 spin_lock(&parent_inode->i_lock); 1028 if (ci->i_shared_gen == di->lease_shared_gen || 1029 snapid <= CEPH_MAXSNAP) { 1030 dout(" clearing %p complete (d_release)\n", 1031 parent_inode); 1032 ci->i_ceph_flags &= ~CEPH_I_COMPLETE; 1033 ci->i_release_count++; 1034 } 1035 spin_unlock(&parent_inode->i_lock); 1036 } 1037 if (di) { 1038 ceph_dentry_lru_del(dentry); 1039 if (di->lease_session) 1040 ceph_put_mds_session(di->lease_session); 1041 kmem_cache_free(ceph_dentry_cachep, di); 1042 dentry->d_fsdata = NULL; 1043 } 1044 } 1045 1046 static int ceph_snapdir_d_revalidate(struct dentry *dentry, 1047 struct nameidata *nd) 1048 { 1049 /* 1050 * Eventually, we'll want to revalidate snapped metadata 1051 * too... probably... 1052 */ 1053 return 1; 1054 } 1055 1056 1057 1058 /* 1059 * read() on a dir. This weird interface hack only works if mounted 1060 * with '-o dirstat'. 1061 */ 1062 static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size, 1063 loff_t *ppos) 1064 { 1065 struct ceph_file_info *cf = file->private_data; 1066 struct inode *inode = file->f_dentry->d_inode; 1067 struct ceph_inode_info *ci = ceph_inode(inode); 1068 int left; 1069 1070 if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT)) 1071 return -EISDIR; 1072 1073 if (!cf->dir_info) { 1074 cf->dir_info = kmalloc(1024, GFP_NOFS); 1075 if (!cf->dir_info) 1076 return -ENOMEM; 1077 cf->dir_info_len = 1078 sprintf(cf->dir_info, 1079 "entries: %20lld\n" 1080 " files: %20lld\n" 1081 " subdirs: %20lld\n" 1082 "rentries: %20lld\n" 1083 " rfiles: %20lld\n" 1084 " rsubdirs: %20lld\n" 1085 "rbytes: %20lld\n" 1086 "rctime: %10ld.%09ld\n", 1087 ci->i_files + ci->i_subdirs, 1088 ci->i_files, 1089 ci->i_subdirs, 1090 ci->i_rfiles + ci->i_rsubdirs, 1091 ci->i_rfiles, 1092 ci->i_rsubdirs, 1093 ci->i_rbytes, 1094 (long)ci->i_rctime.tv_sec, 1095 (long)ci->i_rctime.tv_nsec); 1096 } 1097 1098 if (*ppos >= cf->dir_info_len) 1099 return 0; 1100 size = min_t(unsigned, size, cf->dir_info_len-*ppos); 1101 left = copy_to_user(buf, cf->dir_info + *ppos, size); 1102 if (left == size) 1103 return -EFAULT; 1104 *ppos += (size - left); 1105 return size - left; 1106 } 1107 1108 /* 1109 * an fsync() on a dir will wait for any uncommitted directory 1110 * operations to commit. 1111 */ 1112 static int ceph_dir_fsync(struct file *file, int datasync) 1113 { 1114 struct inode *inode = file->f_path.dentry->d_inode; 1115 struct ceph_inode_info *ci = ceph_inode(inode); 1116 struct list_head *head = &ci->i_unsafe_dirops; 1117 struct ceph_mds_request *req; 1118 u64 last_tid; 1119 int ret = 0; 1120 1121 dout("dir_fsync %p\n", inode); 1122 spin_lock(&ci->i_unsafe_lock); 1123 if (list_empty(head)) 1124 goto out; 1125 1126 req = list_entry(head->prev, 1127 struct ceph_mds_request, r_unsafe_dir_item); 1128 last_tid = req->r_tid; 1129 1130 do { 1131 ceph_mdsc_get_request(req); 1132 spin_unlock(&ci->i_unsafe_lock); 1133 dout("dir_fsync %p wait on tid %llu (until %llu)\n", 1134 inode, req->r_tid, last_tid); 1135 if (req->r_timeout) { 1136 ret = wait_for_completion_timeout( 1137 &req->r_safe_completion, req->r_timeout); 1138 if (ret > 0) 1139 ret = 0; 1140 else if (ret == 0) 1141 ret = -EIO; /* timed out */ 1142 } else { 1143 wait_for_completion(&req->r_safe_completion); 1144 } 1145 spin_lock(&ci->i_unsafe_lock); 1146 ceph_mdsc_put_request(req); 1147 1148 if (ret || list_empty(head)) 1149 break; 1150 req = list_entry(head->next, 1151 struct ceph_mds_request, r_unsafe_dir_item); 1152 } while (req->r_tid < last_tid); 1153 out: 1154 spin_unlock(&ci->i_unsafe_lock); 1155 return ret; 1156 } 1157 1158 /* 1159 * We maintain a private dentry LRU. 1160 * 1161 * FIXME: this needs to be changed to a per-mds lru to be useful. 1162 */ 1163 void ceph_dentry_lru_add(struct dentry *dn) 1164 { 1165 struct ceph_dentry_info *di = ceph_dentry(dn); 1166 struct ceph_mds_client *mdsc; 1167 1168 dout("dentry_lru_add %p %p '%.*s'\n", di, dn, 1169 dn->d_name.len, dn->d_name.name); 1170 if (di) { 1171 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc; 1172 spin_lock(&mdsc->dentry_lru_lock); 1173 list_add_tail(&di->lru, &mdsc->dentry_lru); 1174 mdsc->num_dentry++; 1175 spin_unlock(&mdsc->dentry_lru_lock); 1176 } 1177 } 1178 1179 void ceph_dentry_lru_touch(struct dentry *dn) 1180 { 1181 struct ceph_dentry_info *di = ceph_dentry(dn); 1182 struct ceph_mds_client *mdsc; 1183 1184 dout("dentry_lru_touch %p %p '%.*s' (offset %lld)\n", di, dn, 1185 dn->d_name.len, dn->d_name.name, di->offset); 1186 if (di) { 1187 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc; 1188 spin_lock(&mdsc->dentry_lru_lock); 1189 list_move_tail(&di->lru, &mdsc->dentry_lru); 1190 spin_unlock(&mdsc->dentry_lru_lock); 1191 } 1192 } 1193 1194 void ceph_dentry_lru_del(struct dentry *dn) 1195 { 1196 struct ceph_dentry_info *di = ceph_dentry(dn); 1197 struct ceph_mds_client *mdsc; 1198 1199 dout("dentry_lru_del %p %p '%.*s'\n", di, dn, 1200 dn->d_name.len, dn->d_name.name); 1201 if (di) { 1202 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc; 1203 spin_lock(&mdsc->dentry_lru_lock); 1204 list_del_init(&di->lru); 1205 mdsc->num_dentry--; 1206 spin_unlock(&mdsc->dentry_lru_lock); 1207 } 1208 } 1209 1210 const struct file_operations ceph_dir_fops = { 1211 .read = ceph_read_dir, 1212 .readdir = ceph_readdir, 1213 .llseek = ceph_dir_llseek, 1214 .open = ceph_open, 1215 .release = ceph_release, 1216 .unlocked_ioctl = ceph_ioctl, 1217 .fsync = ceph_dir_fsync, 1218 }; 1219 1220 const struct inode_operations ceph_dir_iops = { 1221 .lookup = ceph_lookup, 1222 .permission = ceph_permission, 1223 .getattr = ceph_getattr, 1224 .setattr = ceph_setattr, 1225 .setxattr = ceph_setxattr, 1226 .getxattr = ceph_getxattr, 1227 .listxattr = ceph_listxattr, 1228 .removexattr = ceph_removexattr, 1229 .mknod = ceph_mknod, 1230 .symlink = ceph_symlink, 1231 .mkdir = ceph_mkdir, 1232 .link = ceph_link, 1233 .unlink = ceph_unlink, 1234 .rmdir = ceph_unlink, 1235 .rename = ceph_rename, 1236 .create = ceph_create, 1237 }; 1238 1239 const struct dentry_operations ceph_dentry_ops = { 1240 .d_revalidate = ceph_d_revalidate, 1241 .d_release = ceph_dentry_release, 1242 }; 1243 1244 const struct dentry_operations ceph_snapdir_dentry_ops = { 1245 .d_revalidate = ceph_snapdir_d_revalidate, 1246 .d_release = ceph_dentry_release, 1247 }; 1248 1249 const struct dentry_operations ceph_snap_dentry_ops = { 1250 .d_release = ceph_dentry_release, 1251 }; 1252