1 #include "ceph_debug.h" 2 3 #include <linux/fs.h> 4 #include <linux/kernel.h> 5 #include <linux/sched.h> 6 #include <linux/vmalloc.h> 7 #include <linux/wait.h> 8 9 #include "super.h" 10 #include "decode.h" 11 #include "messenger.h" 12 13 /* 14 * Capability management 15 * 16 * The Ceph metadata servers control client access to inode metadata 17 * and file data by issuing capabilities, granting clients permission 18 * to read and/or write both inode field and file data to OSDs 19 * (storage nodes). Each capability consists of a set of bits 20 * indicating which operations are allowed. 21 * 22 * If the client holds a *_SHARED cap, the client has a coherent value 23 * that can be safely read from the cached inode. 24 * 25 * In the case of a *_EXCL (exclusive) or FILE_WR capabilities, the 26 * client is allowed to change inode attributes (e.g., file size, 27 * mtime), note its dirty state in the ceph_cap, and asynchronously 28 * flush that metadata change to the MDS. 29 * 30 * In the event of a conflicting operation (perhaps by another 31 * client), the MDS will revoke the conflicting client capabilities. 32 * 33 * In order for a client to cache an inode, it must hold a capability 34 * with at least one MDS server. When inodes are released, release 35 * notifications are batched and periodically sent en masse to the MDS 36 * cluster to release server state. 37 */ 38 39 40 /* 41 * Generate readable cap strings for debugging output. 42 */ 43 #define MAX_CAP_STR 20 44 static char cap_str[MAX_CAP_STR][40]; 45 static DEFINE_SPINLOCK(cap_str_lock); 46 static int last_cap_str; 47 48 static char *gcap_string(char *s, int c) 49 { 50 if (c & CEPH_CAP_GSHARED) 51 *s++ = 's'; 52 if (c & CEPH_CAP_GEXCL) 53 *s++ = 'x'; 54 if (c & CEPH_CAP_GCACHE) 55 *s++ = 'c'; 56 if (c & CEPH_CAP_GRD) 57 *s++ = 'r'; 58 if (c & CEPH_CAP_GWR) 59 *s++ = 'w'; 60 if (c & CEPH_CAP_GBUFFER) 61 *s++ = 'b'; 62 if (c & CEPH_CAP_GLAZYIO) 63 *s++ = 'l'; 64 return s; 65 } 66 67 const char *ceph_cap_string(int caps) 68 { 69 int i; 70 char *s; 71 int c; 72 73 spin_lock(&cap_str_lock); 74 i = last_cap_str++; 75 if (last_cap_str == MAX_CAP_STR) 76 last_cap_str = 0; 77 spin_unlock(&cap_str_lock); 78 79 s = cap_str[i]; 80 81 if (caps & CEPH_CAP_PIN) 82 *s++ = 'p'; 83 84 c = (caps >> CEPH_CAP_SAUTH) & 3; 85 if (c) { 86 *s++ = 'A'; 87 s = gcap_string(s, c); 88 } 89 90 c = (caps >> CEPH_CAP_SLINK) & 3; 91 if (c) { 92 *s++ = 'L'; 93 s = gcap_string(s, c); 94 } 95 96 c = (caps >> CEPH_CAP_SXATTR) & 3; 97 if (c) { 98 *s++ = 'X'; 99 s = gcap_string(s, c); 100 } 101 102 c = caps >> CEPH_CAP_SFILE; 103 if (c) { 104 *s++ = 'F'; 105 s = gcap_string(s, c); 106 } 107 108 if (s == cap_str[i]) 109 *s++ = '-'; 110 *s = 0; 111 return cap_str[i]; 112 } 113 114 /* 115 * Cap reservations 116 * 117 * Maintain a global pool of preallocated struct ceph_caps, referenced 118 * by struct ceph_caps_reservations. This ensures that we preallocate 119 * memory needed to successfully process an MDS response. (If an MDS 120 * sends us cap information and we fail to process it, we will have 121 * problems due to the client and MDS being out of sync.) 122 * 123 * Reservations are 'owned' by a ceph_cap_reservation context. 124 */ 125 static spinlock_t caps_list_lock; 126 static struct list_head caps_list; /* unused (reserved or unreserved) */ 127 static int caps_total_count; /* total caps allocated */ 128 static int caps_use_count; /* in use */ 129 static int caps_reserve_count; /* unused, reserved */ 130 static int caps_avail_count; /* unused, unreserved */ 131 static int caps_min_count; /* keep at least this many (unreserved) */ 132 133 void __init ceph_caps_init(void) 134 { 135 INIT_LIST_HEAD(&caps_list); 136 spin_lock_init(&caps_list_lock); 137 } 138 139 void ceph_caps_finalize(void) 140 { 141 struct ceph_cap *cap; 142 143 spin_lock(&caps_list_lock); 144 while (!list_empty(&caps_list)) { 145 cap = list_first_entry(&caps_list, struct ceph_cap, caps_item); 146 list_del(&cap->caps_item); 147 kmem_cache_free(ceph_cap_cachep, cap); 148 } 149 caps_total_count = 0; 150 caps_avail_count = 0; 151 caps_use_count = 0; 152 caps_reserve_count = 0; 153 caps_min_count = 0; 154 spin_unlock(&caps_list_lock); 155 } 156 157 void ceph_adjust_min_caps(int delta) 158 { 159 spin_lock(&caps_list_lock); 160 caps_min_count += delta; 161 BUG_ON(caps_min_count < 0); 162 spin_unlock(&caps_list_lock); 163 } 164 165 int ceph_reserve_caps(struct ceph_cap_reservation *ctx, int need) 166 { 167 int i; 168 struct ceph_cap *cap; 169 int have; 170 int alloc = 0; 171 LIST_HEAD(newcaps); 172 int ret = 0; 173 174 dout("reserve caps ctx=%p need=%d\n", ctx, need); 175 176 /* first reserve any caps that are already allocated */ 177 spin_lock(&caps_list_lock); 178 if (caps_avail_count >= need) 179 have = need; 180 else 181 have = caps_avail_count; 182 caps_avail_count -= have; 183 caps_reserve_count += have; 184 BUG_ON(caps_total_count != caps_use_count + caps_reserve_count + 185 caps_avail_count); 186 spin_unlock(&caps_list_lock); 187 188 for (i = have; i < need; i++) { 189 cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS); 190 if (!cap) { 191 ret = -ENOMEM; 192 goto out_alloc_count; 193 } 194 list_add(&cap->caps_item, &newcaps); 195 alloc++; 196 } 197 BUG_ON(have + alloc != need); 198 199 spin_lock(&caps_list_lock); 200 caps_total_count += alloc; 201 caps_reserve_count += alloc; 202 list_splice(&newcaps, &caps_list); 203 204 BUG_ON(caps_total_count != caps_use_count + caps_reserve_count + 205 caps_avail_count); 206 spin_unlock(&caps_list_lock); 207 208 ctx->count = need; 209 dout("reserve caps ctx=%p %d = %d used + %d resv + %d avail\n", 210 ctx, caps_total_count, caps_use_count, caps_reserve_count, 211 caps_avail_count); 212 return 0; 213 214 out_alloc_count: 215 /* we didn't manage to reserve as much as we needed */ 216 pr_warning("reserve caps ctx=%p ENOMEM need=%d got=%d\n", 217 ctx, need, have); 218 return ret; 219 } 220 221 int ceph_unreserve_caps(struct ceph_cap_reservation *ctx) 222 { 223 dout("unreserve caps ctx=%p count=%d\n", ctx, ctx->count); 224 if (ctx->count) { 225 spin_lock(&caps_list_lock); 226 BUG_ON(caps_reserve_count < ctx->count); 227 caps_reserve_count -= ctx->count; 228 caps_avail_count += ctx->count; 229 ctx->count = 0; 230 dout("unreserve caps %d = %d used + %d resv + %d avail\n", 231 caps_total_count, caps_use_count, caps_reserve_count, 232 caps_avail_count); 233 BUG_ON(caps_total_count != caps_use_count + caps_reserve_count + 234 caps_avail_count); 235 spin_unlock(&caps_list_lock); 236 } 237 return 0; 238 } 239 240 static struct ceph_cap *get_cap(struct ceph_cap_reservation *ctx) 241 { 242 struct ceph_cap *cap = NULL; 243 244 /* temporary, until we do something about cap import/export */ 245 if (!ctx) 246 return kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS); 247 248 spin_lock(&caps_list_lock); 249 dout("get_cap ctx=%p (%d) %d = %d used + %d resv + %d avail\n", 250 ctx, ctx->count, caps_total_count, caps_use_count, 251 caps_reserve_count, caps_avail_count); 252 BUG_ON(!ctx->count); 253 BUG_ON(ctx->count > caps_reserve_count); 254 BUG_ON(list_empty(&caps_list)); 255 256 ctx->count--; 257 caps_reserve_count--; 258 caps_use_count++; 259 260 cap = list_first_entry(&caps_list, struct ceph_cap, caps_item); 261 list_del(&cap->caps_item); 262 263 BUG_ON(caps_total_count != caps_use_count + caps_reserve_count + 264 caps_avail_count); 265 spin_unlock(&caps_list_lock); 266 return cap; 267 } 268 269 void ceph_put_cap(struct ceph_cap *cap) 270 { 271 spin_lock(&caps_list_lock); 272 dout("put_cap %p %d = %d used + %d resv + %d avail\n", 273 cap, caps_total_count, caps_use_count, 274 caps_reserve_count, caps_avail_count); 275 caps_use_count--; 276 /* 277 * Keep some preallocated caps around (ceph_min_count), to 278 * avoid lots of free/alloc churn. 279 */ 280 if (caps_avail_count >= caps_reserve_count + caps_min_count) { 281 caps_total_count--; 282 kmem_cache_free(ceph_cap_cachep, cap); 283 } else { 284 caps_avail_count++; 285 list_add(&cap->caps_item, &caps_list); 286 } 287 288 BUG_ON(caps_total_count != caps_use_count + caps_reserve_count + 289 caps_avail_count); 290 spin_unlock(&caps_list_lock); 291 } 292 293 void ceph_reservation_status(struct ceph_client *client, 294 int *total, int *avail, int *used, int *reserved, 295 int *min) 296 { 297 if (total) 298 *total = caps_total_count; 299 if (avail) 300 *avail = caps_avail_count; 301 if (used) 302 *used = caps_use_count; 303 if (reserved) 304 *reserved = caps_reserve_count; 305 if (min) 306 *min = caps_min_count; 307 } 308 309 /* 310 * Find ceph_cap for given mds, if any. 311 * 312 * Called with i_lock held. 313 */ 314 static struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds) 315 { 316 struct ceph_cap *cap; 317 struct rb_node *n = ci->i_caps.rb_node; 318 319 while (n) { 320 cap = rb_entry(n, struct ceph_cap, ci_node); 321 if (mds < cap->mds) 322 n = n->rb_left; 323 else if (mds > cap->mds) 324 n = n->rb_right; 325 else 326 return cap; 327 } 328 return NULL; 329 } 330 331 /* 332 * Return id of any MDS with a cap, preferably FILE_WR|WRBUFFER|EXCL, else 333 * -1. 334 */ 335 static int __ceph_get_cap_mds(struct ceph_inode_info *ci, u32 *mseq) 336 { 337 struct ceph_cap *cap; 338 int mds = -1; 339 struct rb_node *p; 340 341 /* prefer mds with WR|WRBUFFER|EXCL caps */ 342 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) { 343 cap = rb_entry(p, struct ceph_cap, ci_node); 344 mds = cap->mds; 345 if (mseq) 346 *mseq = cap->mseq; 347 if (cap->issued & (CEPH_CAP_FILE_WR | 348 CEPH_CAP_FILE_BUFFER | 349 CEPH_CAP_FILE_EXCL)) 350 break; 351 } 352 return mds; 353 } 354 355 int ceph_get_cap_mds(struct inode *inode) 356 { 357 int mds; 358 spin_lock(&inode->i_lock); 359 mds = __ceph_get_cap_mds(ceph_inode(inode), NULL); 360 spin_unlock(&inode->i_lock); 361 return mds; 362 } 363 364 /* 365 * Called under i_lock. 366 */ 367 static void __insert_cap_node(struct ceph_inode_info *ci, 368 struct ceph_cap *new) 369 { 370 struct rb_node **p = &ci->i_caps.rb_node; 371 struct rb_node *parent = NULL; 372 struct ceph_cap *cap = NULL; 373 374 while (*p) { 375 parent = *p; 376 cap = rb_entry(parent, struct ceph_cap, ci_node); 377 if (new->mds < cap->mds) 378 p = &(*p)->rb_left; 379 else if (new->mds > cap->mds) 380 p = &(*p)->rb_right; 381 else 382 BUG(); 383 } 384 385 rb_link_node(&new->ci_node, parent, p); 386 rb_insert_color(&new->ci_node, &ci->i_caps); 387 } 388 389 /* 390 * (re)set cap hold timeouts, which control the delayed release 391 * of unused caps back to the MDS. Should be called on cap use. 392 */ 393 static void __cap_set_timeouts(struct ceph_mds_client *mdsc, 394 struct ceph_inode_info *ci) 395 { 396 struct ceph_mount_args *ma = mdsc->client->mount_args; 397 398 ci->i_hold_caps_min = round_jiffies(jiffies + 399 ma->caps_wanted_delay_min * HZ); 400 ci->i_hold_caps_max = round_jiffies(jiffies + 401 ma->caps_wanted_delay_max * HZ); 402 dout("__cap_set_timeouts %p min %lu max %lu\n", &ci->vfs_inode, 403 ci->i_hold_caps_min - jiffies, ci->i_hold_caps_max - jiffies); 404 } 405 406 /* 407 * (Re)queue cap at the end of the delayed cap release list. 408 * 409 * If I_FLUSH is set, leave the inode at the front of the list. 410 * 411 * Caller holds i_lock 412 * -> we take mdsc->cap_delay_lock 413 */ 414 static void __cap_delay_requeue(struct ceph_mds_client *mdsc, 415 struct ceph_inode_info *ci) 416 { 417 __cap_set_timeouts(mdsc, ci); 418 dout("__cap_delay_requeue %p flags %d at %lu\n", &ci->vfs_inode, 419 ci->i_ceph_flags, ci->i_hold_caps_max); 420 if (!mdsc->stopping) { 421 spin_lock(&mdsc->cap_delay_lock); 422 if (!list_empty(&ci->i_cap_delay_list)) { 423 if (ci->i_ceph_flags & CEPH_I_FLUSH) 424 goto no_change; 425 list_del_init(&ci->i_cap_delay_list); 426 } 427 list_add_tail(&ci->i_cap_delay_list, &mdsc->cap_delay_list); 428 no_change: 429 spin_unlock(&mdsc->cap_delay_lock); 430 } 431 } 432 433 /* 434 * Queue an inode for immediate writeback. Mark inode with I_FLUSH, 435 * indicating we should send a cap message to flush dirty metadata 436 * asap, and move to the front of the delayed cap list. 437 */ 438 static void __cap_delay_requeue_front(struct ceph_mds_client *mdsc, 439 struct ceph_inode_info *ci) 440 { 441 dout("__cap_delay_requeue_front %p\n", &ci->vfs_inode); 442 spin_lock(&mdsc->cap_delay_lock); 443 ci->i_ceph_flags |= CEPH_I_FLUSH; 444 if (!list_empty(&ci->i_cap_delay_list)) 445 list_del_init(&ci->i_cap_delay_list); 446 list_add(&ci->i_cap_delay_list, &mdsc->cap_delay_list); 447 spin_unlock(&mdsc->cap_delay_lock); 448 } 449 450 /* 451 * Cancel delayed work on cap. 452 * 453 * Caller must hold i_lock. 454 */ 455 static void __cap_delay_cancel(struct ceph_mds_client *mdsc, 456 struct ceph_inode_info *ci) 457 { 458 dout("__cap_delay_cancel %p\n", &ci->vfs_inode); 459 if (list_empty(&ci->i_cap_delay_list)) 460 return; 461 spin_lock(&mdsc->cap_delay_lock); 462 list_del_init(&ci->i_cap_delay_list); 463 spin_unlock(&mdsc->cap_delay_lock); 464 } 465 466 /* 467 * Common issue checks for add_cap, handle_cap_grant. 468 */ 469 static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap, 470 unsigned issued) 471 { 472 unsigned had = __ceph_caps_issued(ci, NULL); 473 474 /* 475 * Each time we receive FILE_CACHE anew, we increment 476 * i_rdcache_gen. 477 */ 478 if ((issued & CEPH_CAP_FILE_CACHE) && 479 (had & CEPH_CAP_FILE_CACHE) == 0) 480 ci->i_rdcache_gen++; 481 482 /* 483 * if we are newly issued FILE_SHARED, clear I_COMPLETE; we 484 * don't know what happened to this directory while we didn't 485 * have the cap. 486 */ 487 if ((issued & CEPH_CAP_FILE_SHARED) && 488 (had & CEPH_CAP_FILE_SHARED) == 0) { 489 ci->i_shared_gen++; 490 if (S_ISDIR(ci->vfs_inode.i_mode)) { 491 dout(" marking %p NOT complete\n", &ci->vfs_inode); 492 ci->i_ceph_flags &= ~CEPH_I_COMPLETE; 493 } 494 } 495 } 496 497 /* 498 * Add a capability under the given MDS session. 499 * 500 * Caller should hold session snap_rwsem (read) and s_mutex. 501 * 502 * @fmode is the open file mode, if we are opening a file, otherwise 503 * it is < 0. (This is so we can atomically add the cap and add an 504 * open file reference to it.) 505 */ 506 int ceph_add_cap(struct inode *inode, 507 struct ceph_mds_session *session, u64 cap_id, 508 int fmode, unsigned issued, unsigned wanted, 509 unsigned seq, unsigned mseq, u64 realmino, int flags, 510 struct ceph_cap_reservation *caps_reservation) 511 { 512 struct ceph_mds_client *mdsc = &ceph_inode_to_client(inode)->mdsc; 513 struct ceph_inode_info *ci = ceph_inode(inode); 514 struct ceph_cap *new_cap = NULL; 515 struct ceph_cap *cap; 516 int mds = session->s_mds; 517 int actual_wanted; 518 519 dout("add_cap %p mds%d cap %llx %s seq %d\n", inode, 520 session->s_mds, cap_id, ceph_cap_string(issued), seq); 521 522 /* 523 * If we are opening the file, include file mode wanted bits 524 * in wanted. 525 */ 526 if (fmode >= 0) 527 wanted |= ceph_caps_for_mode(fmode); 528 529 retry: 530 spin_lock(&inode->i_lock); 531 cap = __get_cap_for_mds(ci, mds); 532 if (!cap) { 533 if (new_cap) { 534 cap = new_cap; 535 new_cap = NULL; 536 } else { 537 spin_unlock(&inode->i_lock); 538 new_cap = get_cap(caps_reservation); 539 if (new_cap == NULL) 540 return -ENOMEM; 541 goto retry; 542 } 543 544 cap->issued = 0; 545 cap->implemented = 0; 546 cap->mds = mds; 547 cap->mds_wanted = 0; 548 549 cap->ci = ci; 550 __insert_cap_node(ci, cap); 551 552 /* clear out old exporting info? (i.e. on cap import) */ 553 if (ci->i_cap_exporting_mds == mds) { 554 ci->i_cap_exporting_issued = 0; 555 ci->i_cap_exporting_mseq = 0; 556 ci->i_cap_exporting_mds = -1; 557 } 558 559 /* add to session cap list */ 560 cap->session = session; 561 spin_lock(&session->s_cap_lock); 562 list_add_tail(&cap->session_caps, &session->s_caps); 563 session->s_nr_caps++; 564 spin_unlock(&session->s_cap_lock); 565 } 566 567 if (!ci->i_snap_realm) { 568 /* 569 * add this inode to the appropriate snap realm 570 */ 571 struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc, 572 realmino); 573 if (realm) { 574 ceph_get_snap_realm(mdsc, realm); 575 spin_lock(&realm->inodes_with_caps_lock); 576 ci->i_snap_realm = realm; 577 list_add(&ci->i_snap_realm_item, 578 &realm->inodes_with_caps); 579 spin_unlock(&realm->inodes_with_caps_lock); 580 } else { 581 pr_err("ceph_add_cap: couldn't find snap realm %llx\n", 582 realmino); 583 } 584 } 585 586 __check_cap_issue(ci, cap, issued); 587 588 /* 589 * If we are issued caps we don't want, or the mds' wanted 590 * value appears to be off, queue a check so we'll release 591 * later and/or update the mds wanted value. 592 */ 593 actual_wanted = __ceph_caps_wanted(ci); 594 if ((wanted & ~actual_wanted) || 595 (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) { 596 dout(" issued %s, mds wanted %s, actual %s, queueing\n", 597 ceph_cap_string(issued), ceph_cap_string(wanted), 598 ceph_cap_string(actual_wanted)); 599 __cap_delay_requeue(mdsc, ci); 600 } 601 602 if (flags & CEPH_CAP_FLAG_AUTH) 603 ci->i_auth_cap = cap; 604 else if (ci->i_auth_cap == cap) 605 ci->i_auth_cap = NULL; 606 607 dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n", 608 inode, ceph_vinop(inode), cap, ceph_cap_string(issued), 609 ceph_cap_string(issued|cap->issued), seq, mds); 610 cap->cap_id = cap_id; 611 cap->issued = issued; 612 cap->implemented |= issued; 613 cap->mds_wanted |= wanted; 614 cap->seq = seq; 615 cap->issue_seq = seq; 616 cap->mseq = mseq; 617 cap->cap_gen = session->s_cap_gen; 618 619 if (fmode >= 0) 620 __ceph_get_fmode(ci, fmode); 621 spin_unlock(&inode->i_lock); 622 wake_up(&ci->i_cap_wq); 623 return 0; 624 } 625 626 /* 627 * Return true if cap has not timed out and belongs to the current 628 * generation of the MDS session (i.e. has not gone 'stale' due to 629 * us losing touch with the mds). 630 */ 631 static int __cap_is_valid(struct ceph_cap *cap) 632 { 633 unsigned long ttl; 634 u32 gen; 635 636 spin_lock(&cap->session->s_cap_lock); 637 gen = cap->session->s_cap_gen; 638 ttl = cap->session->s_cap_ttl; 639 spin_unlock(&cap->session->s_cap_lock); 640 641 if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) { 642 dout("__cap_is_valid %p cap %p issued %s " 643 "but STALE (gen %u vs %u)\n", &cap->ci->vfs_inode, 644 cap, ceph_cap_string(cap->issued), cap->cap_gen, gen); 645 return 0; 646 } 647 648 return 1; 649 } 650 651 /* 652 * Return set of valid cap bits issued to us. Note that caps time 653 * out, and may be invalidated in bulk if the client session times out 654 * and session->s_cap_gen is bumped. 655 */ 656 int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented) 657 { 658 int have = ci->i_snap_caps; 659 struct ceph_cap *cap; 660 struct rb_node *p; 661 662 if (implemented) 663 *implemented = 0; 664 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) { 665 cap = rb_entry(p, struct ceph_cap, ci_node); 666 if (!__cap_is_valid(cap)) 667 continue; 668 dout("__ceph_caps_issued %p cap %p issued %s\n", 669 &ci->vfs_inode, cap, ceph_cap_string(cap->issued)); 670 have |= cap->issued; 671 if (implemented) 672 *implemented |= cap->implemented; 673 } 674 return have; 675 } 676 677 /* 678 * Get cap bits issued by caps other than @ocap 679 */ 680 int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap) 681 { 682 int have = ci->i_snap_caps; 683 struct ceph_cap *cap; 684 struct rb_node *p; 685 686 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) { 687 cap = rb_entry(p, struct ceph_cap, ci_node); 688 if (cap == ocap) 689 continue; 690 if (!__cap_is_valid(cap)) 691 continue; 692 have |= cap->issued; 693 } 694 return have; 695 } 696 697 /* 698 * Move a cap to the end of the LRU (oldest caps at list head, newest 699 * at list tail). 700 */ 701 static void __touch_cap(struct ceph_cap *cap) 702 { 703 struct ceph_mds_session *s = cap->session; 704 705 spin_lock(&s->s_cap_lock); 706 if (s->s_cap_iterator == NULL) { 707 dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap, 708 s->s_mds); 709 list_move_tail(&cap->session_caps, &s->s_caps); 710 } else { 711 dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n", 712 &cap->ci->vfs_inode, cap, s->s_mds); 713 } 714 spin_unlock(&s->s_cap_lock); 715 } 716 717 /* 718 * Check if we hold the given mask. If so, move the cap(s) to the 719 * front of their respective LRUs. (This is the preferred way for 720 * callers to check for caps they want.) 721 */ 722 int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch) 723 { 724 struct ceph_cap *cap; 725 struct rb_node *p; 726 int have = ci->i_snap_caps; 727 728 if ((have & mask) == mask) { 729 dout("__ceph_caps_issued_mask %p snap issued %s" 730 " (mask %s)\n", &ci->vfs_inode, 731 ceph_cap_string(have), 732 ceph_cap_string(mask)); 733 return 1; 734 } 735 736 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) { 737 cap = rb_entry(p, struct ceph_cap, ci_node); 738 if (!__cap_is_valid(cap)) 739 continue; 740 if ((cap->issued & mask) == mask) { 741 dout("__ceph_caps_issued_mask %p cap %p issued %s" 742 " (mask %s)\n", &ci->vfs_inode, cap, 743 ceph_cap_string(cap->issued), 744 ceph_cap_string(mask)); 745 if (touch) 746 __touch_cap(cap); 747 return 1; 748 } 749 750 /* does a combination of caps satisfy mask? */ 751 have |= cap->issued; 752 if ((have & mask) == mask) { 753 dout("__ceph_caps_issued_mask %p combo issued %s" 754 " (mask %s)\n", &ci->vfs_inode, 755 ceph_cap_string(cap->issued), 756 ceph_cap_string(mask)); 757 if (touch) { 758 struct rb_node *q; 759 760 /* touch this + preceeding caps */ 761 __touch_cap(cap); 762 for (q = rb_first(&ci->i_caps); q != p; 763 q = rb_next(q)) { 764 cap = rb_entry(q, struct ceph_cap, 765 ci_node); 766 if (!__cap_is_valid(cap)) 767 continue; 768 __touch_cap(cap); 769 } 770 } 771 return 1; 772 } 773 } 774 775 return 0; 776 } 777 778 /* 779 * Return true if mask caps are currently being revoked by an MDS. 780 */ 781 int ceph_caps_revoking(struct ceph_inode_info *ci, int mask) 782 { 783 struct inode *inode = &ci->vfs_inode; 784 struct ceph_cap *cap; 785 struct rb_node *p; 786 int ret = 0; 787 788 spin_lock(&inode->i_lock); 789 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) { 790 cap = rb_entry(p, struct ceph_cap, ci_node); 791 if (__cap_is_valid(cap) && 792 (cap->implemented & ~cap->issued & mask)) { 793 ret = 1; 794 break; 795 } 796 } 797 spin_unlock(&inode->i_lock); 798 dout("ceph_caps_revoking %p %s = %d\n", inode, 799 ceph_cap_string(mask), ret); 800 return ret; 801 } 802 803 int __ceph_caps_used(struct ceph_inode_info *ci) 804 { 805 int used = 0; 806 if (ci->i_pin_ref) 807 used |= CEPH_CAP_PIN; 808 if (ci->i_rd_ref) 809 used |= CEPH_CAP_FILE_RD; 810 if (ci->i_rdcache_ref || ci->i_rdcache_gen) 811 used |= CEPH_CAP_FILE_CACHE; 812 if (ci->i_wr_ref) 813 used |= CEPH_CAP_FILE_WR; 814 if (ci->i_wrbuffer_ref) 815 used |= CEPH_CAP_FILE_BUFFER; 816 return used; 817 } 818 819 /* 820 * wanted, by virtue of open file modes 821 */ 822 int __ceph_caps_file_wanted(struct ceph_inode_info *ci) 823 { 824 int want = 0; 825 int mode; 826 for (mode = 0; mode < 4; mode++) 827 if (ci->i_nr_by_mode[mode]) 828 want |= ceph_caps_for_mode(mode); 829 return want; 830 } 831 832 /* 833 * Return caps we have registered with the MDS(s) as 'wanted'. 834 */ 835 int __ceph_caps_mds_wanted(struct ceph_inode_info *ci) 836 { 837 struct ceph_cap *cap; 838 struct rb_node *p; 839 int mds_wanted = 0; 840 841 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) { 842 cap = rb_entry(p, struct ceph_cap, ci_node); 843 if (!__cap_is_valid(cap)) 844 continue; 845 mds_wanted |= cap->mds_wanted; 846 } 847 return mds_wanted; 848 } 849 850 /* 851 * called under i_lock 852 */ 853 static int __ceph_is_any_caps(struct ceph_inode_info *ci) 854 { 855 return !RB_EMPTY_ROOT(&ci->i_caps) || ci->i_cap_exporting_mds >= 0; 856 } 857 858 /* 859 * caller should hold i_lock, and session s_mutex. 860 * returns true if this is the last cap. if so, caller should iput. 861 */ 862 void __ceph_remove_cap(struct ceph_cap *cap) 863 { 864 struct ceph_mds_session *session = cap->session; 865 struct ceph_inode_info *ci = cap->ci; 866 struct ceph_mds_client *mdsc = &ceph_client(ci->vfs_inode.i_sb)->mdsc; 867 868 dout("__ceph_remove_cap %p from %p\n", cap, &ci->vfs_inode); 869 870 /* remove from inode list */ 871 rb_erase(&cap->ci_node, &ci->i_caps); 872 cap->ci = NULL; 873 if (ci->i_auth_cap == cap) 874 ci->i_auth_cap = NULL; 875 876 /* remove from session list */ 877 spin_lock(&session->s_cap_lock); 878 if (session->s_cap_iterator == cap) { 879 /* not yet, we are iterating over this very cap */ 880 dout("__ceph_remove_cap delaying %p removal from session %p\n", 881 cap, cap->session); 882 } else { 883 list_del_init(&cap->session_caps); 884 session->s_nr_caps--; 885 cap->session = NULL; 886 } 887 spin_unlock(&session->s_cap_lock); 888 889 if (cap->session == NULL) 890 ceph_put_cap(cap); 891 892 if (!__ceph_is_any_caps(ci) && ci->i_snap_realm) { 893 struct ceph_snap_realm *realm = ci->i_snap_realm; 894 spin_lock(&realm->inodes_with_caps_lock); 895 list_del_init(&ci->i_snap_realm_item); 896 ci->i_snap_realm_counter++; 897 ci->i_snap_realm = NULL; 898 spin_unlock(&realm->inodes_with_caps_lock); 899 ceph_put_snap_realm(mdsc, realm); 900 } 901 if (!__ceph_is_any_real_caps(ci)) 902 __cap_delay_cancel(mdsc, ci); 903 } 904 905 /* 906 * Build and send a cap message to the given MDS. 907 * 908 * Caller should be holding s_mutex. 909 */ 910 static int send_cap_msg(struct ceph_mds_session *session, 911 u64 ino, u64 cid, int op, 912 int caps, int wanted, int dirty, 913 u32 seq, u64 flush_tid, u32 issue_seq, u32 mseq, 914 u64 size, u64 max_size, 915 struct timespec *mtime, struct timespec *atime, 916 u64 time_warp_seq, 917 uid_t uid, gid_t gid, mode_t mode, 918 u64 xattr_version, 919 struct ceph_buffer *xattrs_buf, 920 u64 follows) 921 { 922 struct ceph_mds_caps *fc; 923 struct ceph_msg *msg; 924 925 dout("send_cap_msg %s %llx %llx caps %s wanted %s dirty %s" 926 " seq %u/%u mseq %u follows %lld size %llu/%llu" 927 " xattr_ver %llu xattr_len %d\n", ceph_cap_op_name(op), 928 cid, ino, ceph_cap_string(caps), ceph_cap_string(wanted), 929 ceph_cap_string(dirty), 930 seq, issue_seq, mseq, follows, size, max_size, 931 xattr_version, xattrs_buf ? (int)xattrs_buf->vec.iov_len : 0); 932 933 msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, sizeof(*fc), 0, 0, NULL); 934 if (IS_ERR(msg)) 935 return PTR_ERR(msg); 936 937 msg->hdr.tid = cpu_to_le64(flush_tid); 938 939 fc = msg->front.iov_base; 940 memset(fc, 0, sizeof(*fc)); 941 942 fc->cap_id = cpu_to_le64(cid); 943 fc->op = cpu_to_le32(op); 944 fc->seq = cpu_to_le32(seq); 945 fc->issue_seq = cpu_to_le32(issue_seq); 946 fc->migrate_seq = cpu_to_le32(mseq); 947 fc->caps = cpu_to_le32(caps); 948 fc->wanted = cpu_to_le32(wanted); 949 fc->dirty = cpu_to_le32(dirty); 950 fc->ino = cpu_to_le64(ino); 951 fc->snap_follows = cpu_to_le64(follows); 952 953 fc->size = cpu_to_le64(size); 954 fc->max_size = cpu_to_le64(max_size); 955 if (mtime) 956 ceph_encode_timespec(&fc->mtime, mtime); 957 if (atime) 958 ceph_encode_timespec(&fc->atime, atime); 959 fc->time_warp_seq = cpu_to_le32(time_warp_seq); 960 961 fc->uid = cpu_to_le32(uid); 962 fc->gid = cpu_to_le32(gid); 963 fc->mode = cpu_to_le32(mode); 964 965 fc->xattr_version = cpu_to_le64(xattr_version); 966 if (xattrs_buf) { 967 msg->middle = ceph_buffer_get(xattrs_buf); 968 fc->xattr_len = cpu_to_le32(xattrs_buf->vec.iov_len); 969 msg->hdr.middle_len = cpu_to_le32(xattrs_buf->vec.iov_len); 970 } 971 972 ceph_con_send(&session->s_con, msg); 973 return 0; 974 } 975 976 /* 977 * Queue cap releases when an inode is dropped from our 978 * cache. 979 */ 980 void ceph_queue_caps_release(struct inode *inode) 981 { 982 struct ceph_inode_info *ci = ceph_inode(inode); 983 struct rb_node *p; 984 985 spin_lock(&inode->i_lock); 986 p = rb_first(&ci->i_caps); 987 while (p) { 988 struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node); 989 struct ceph_mds_session *session = cap->session; 990 struct ceph_msg *msg; 991 struct ceph_mds_cap_release *head; 992 struct ceph_mds_cap_item *item; 993 994 spin_lock(&session->s_cap_lock); 995 BUG_ON(!session->s_num_cap_releases); 996 msg = list_first_entry(&session->s_cap_releases, 997 struct ceph_msg, list_head); 998 999 dout(" adding %p release to mds%d msg %p (%d left)\n", 1000 inode, session->s_mds, msg, session->s_num_cap_releases); 1001 1002 BUG_ON(msg->front.iov_len + sizeof(*item) > PAGE_CACHE_SIZE); 1003 head = msg->front.iov_base; 1004 head->num = cpu_to_le32(le32_to_cpu(head->num) + 1); 1005 item = msg->front.iov_base + msg->front.iov_len; 1006 item->ino = cpu_to_le64(ceph_ino(inode)); 1007 item->cap_id = cpu_to_le64(cap->cap_id); 1008 item->migrate_seq = cpu_to_le32(cap->mseq); 1009 item->seq = cpu_to_le32(cap->issue_seq); 1010 1011 session->s_num_cap_releases--; 1012 1013 msg->front.iov_len += sizeof(*item); 1014 if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) { 1015 dout(" release msg %p full\n", msg); 1016 list_move_tail(&msg->list_head, 1017 &session->s_cap_releases_done); 1018 } else { 1019 dout(" release msg %p at %d/%d (%d)\n", msg, 1020 (int)le32_to_cpu(head->num), 1021 (int)CEPH_CAPS_PER_RELEASE, 1022 (int)msg->front.iov_len); 1023 } 1024 spin_unlock(&session->s_cap_lock); 1025 p = rb_next(p); 1026 __ceph_remove_cap(cap); 1027 1028 } 1029 spin_unlock(&inode->i_lock); 1030 } 1031 1032 /* 1033 * Send a cap msg on the given inode. Update our caps state, then 1034 * drop i_lock and send the message. 1035 * 1036 * Make note of max_size reported/requested from mds, revoked caps 1037 * that have now been implemented. 1038 * 1039 * Make half-hearted attempt ot to invalidate page cache if we are 1040 * dropping RDCACHE. Note that this will leave behind locked pages 1041 * that we'll then need to deal with elsewhere. 1042 * 1043 * Return non-zero if delayed release, or we experienced an error 1044 * such that the caller should requeue + retry later. 1045 * 1046 * called with i_lock, then drops it. 1047 * caller should hold snap_rwsem (read), s_mutex. 1048 */ 1049 static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap, 1050 int op, int used, int want, int retain, int flushing, 1051 unsigned *pflush_tid) 1052 __releases(cap->ci->vfs_inode->i_lock) 1053 { 1054 struct ceph_inode_info *ci = cap->ci; 1055 struct inode *inode = &ci->vfs_inode; 1056 u64 cap_id = cap->cap_id; 1057 int held, revoking, dropping, keep; 1058 u64 seq, issue_seq, mseq, time_warp_seq, follows; 1059 u64 size, max_size; 1060 struct timespec mtime, atime; 1061 int wake = 0; 1062 mode_t mode; 1063 uid_t uid; 1064 gid_t gid; 1065 struct ceph_mds_session *session; 1066 u64 xattr_version = 0; 1067 int delayed = 0; 1068 u64 flush_tid = 0; 1069 int i; 1070 int ret; 1071 1072 held = cap->issued | cap->implemented; 1073 revoking = cap->implemented & ~cap->issued; 1074 retain &= ~revoking; 1075 dropping = cap->issued & ~retain; 1076 1077 dout("__send_cap %p cap %p session %p %s -> %s (revoking %s)\n", 1078 inode, cap, cap->session, 1079 ceph_cap_string(held), ceph_cap_string(held & retain), 1080 ceph_cap_string(revoking)); 1081 BUG_ON((retain & CEPH_CAP_PIN) == 0); 1082 1083 session = cap->session; 1084 1085 /* don't release wanted unless we've waited a bit. */ 1086 if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 && 1087 time_before(jiffies, ci->i_hold_caps_min)) { 1088 dout(" delaying issued %s -> %s, wanted %s -> %s on send\n", 1089 ceph_cap_string(cap->issued), 1090 ceph_cap_string(cap->issued & retain), 1091 ceph_cap_string(cap->mds_wanted), 1092 ceph_cap_string(want)); 1093 want |= cap->mds_wanted; 1094 retain |= cap->issued; 1095 delayed = 1; 1096 } 1097 ci->i_ceph_flags &= ~(CEPH_I_NODELAY | CEPH_I_FLUSH); 1098 1099 cap->issued &= retain; /* drop bits we don't want */ 1100 if (cap->implemented & ~cap->issued) { 1101 /* 1102 * Wake up any waiters on wanted -> needed transition. 1103 * This is due to the weird transition from buffered 1104 * to sync IO... we need to flush dirty pages _before_ 1105 * allowing sync writes to avoid reordering. 1106 */ 1107 wake = 1; 1108 } 1109 cap->implemented &= cap->issued | used; 1110 cap->mds_wanted = want; 1111 1112 if (flushing) { 1113 /* 1114 * assign a tid for flush operations so we can avoid 1115 * flush1 -> dirty1 -> flush2 -> flushack1 -> mark 1116 * clean type races. track latest tid for every bit 1117 * so we can handle flush AxFw, flush Fw, and have the 1118 * first ack clean Ax. 1119 */ 1120 flush_tid = ++ci->i_cap_flush_last_tid; 1121 if (pflush_tid) 1122 *pflush_tid = flush_tid; 1123 dout(" cap_flush_tid %d\n", (int)flush_tid); 1124 for (i = 0; i < CEPH_CAP_BITS; i++) 1125 if (flushing & (1 << i)) 1126 ci->i_cap_flush_tid[i] = flush_tid; 1127 } 1128 1129 keep = cap->implemented; 1130 seq = cap->seq; 1131 issue_seq = cap->issue_seq; 1132 mseq = cap->mseq; 1133 size = inode->i_size; 1134 ci->i_reported_size = size; 1135 max_size = ci->i_wanted_max_size; 1136 ci->i_requested_max_size = max_size; 1137 mtime = inode->i_mtime; 1138 atime = inode->i_atime; 1139 time_warp_seq = ci->i_time_warp_seq; 1140 follows = ci->i_snap_realm->cached_context->seq; 1141 uid = inode->i_uid; 1142 gid = inode->i_gid; 1143 mode = inode->i_mode; 1144 1145 if (dropping & CEPH_CAP_XATTR_EXCL) { 1146 __ceph_build_xattrs_blob(ci); 1147 xattr_version = ci->i_xattrs.version + 1; 1148 } 1149 1150 spin_unlock(&inode->i_lock); 1151 1152 ret = send_cap_msg(session, ceph_vino(inode).ino, cap_id, 1153 op, keep, want, flushing, seq, flush_tid, issue_seq, mseq, 1154 size, max_size, &mtime, &atime, time_warp_seq, 1155 uid, gid, mode, 1156 xattr_version, 1157 (flushing & CEPH_CAP_XATTR_EXCL) ? ci->i_xattrs.blob : NULL, 1158 follows); 1159 if (ret < 0) { 1160 dout("error sending cap msg, must requeue %p\n", inode); 1161 delayed = 1; 1162 } 1163 1164 if (wake) 1165 wake_up(&ci->i_cap_wq); 1166 1167 return delayed; 1168 } 1169 1170 /* 1171 * When a snapshot is taken, clients accumulate dirty metadata on 1172 * inodes with capabilities in ceph_cap_snaps to describe the file 1173 * state at the time the snapshot was taken. This must be flushed 1174 * asynchronously back to the MDS once sync writes complete and dirty 1175 * data is written out. 1176 * 1177 * Called under i_lock. Takes s_mutex as needed. 1178 */ 1179 void __ceph_flush_snaps(struct ceph_inode_info *ci, 1180 struct ceph_mds_session **psession) 1181 { 1182 struct inode *inode = &ci->vfs_inode; 1183 int mds; 1184 struct ceph_cap_snap *capsnap; 1185 u32 mseq; 1186 struct ceph_mds_client *mdsc = &ceph_inode_to_client(inode)->mdsc; 1187 struct ceph_mds_session *session = NULL; /* if session != NULL, we hold 1188 session->s_mutex */ 1189 u64 next_follows = 0; /* keep track of how far we've gotten through the 1190 i_cap_snaps list, and skip these entries next time 1191 around to avoid an infinite loop */ 1192 1193 if (psession) 1194 session = *psession; 1195 1196 dout("__flush_snaps %p\n", inode); 1197 retry: 1198 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) { 1199 /* avoid an infiniute loop after retry */ 1200 if (capsnap->follows < next_follows) 1201 continue; 1202 /* 1203 * we need to wait for sync writes to complete and for dirty 1204 * pages to be written out. 1205 */ 1206 if (capsnap->dirty_pages || capsnap->writing) 1207 continue; 1208 1209 /* pick mds, take s_mutex */ 1210 mds = __ceph_get_cap_mds(ci, &mseq); 1211 if (session && session->s_mds != mds) { 1212 dout("oops, wrong session %p mutex\n", session); 1213 mutex_unlock(&session->s_mutex); 1214 ceph_put_mds_session(session); 1215 session = NULL; 1216 } 1217 if (!session) { 1218 spin_unlock(&inode->i_lock); 1219 mutex_lock(&mdsc->mutex); 1220 session = __ceph_lookup_mds_session(mdsc, mds); 1221 mutex_unlock(&mdsc->mutex); 1222 if (session) { 1223 dout("inverting session/ino locks on %p\n", 1224 session); 1225 mutex_lock(&session->s_mutex); 1226 } 1227 /* 1228 * if session == NULL, we raced against a cap 1229 * deletion. retry, and we'll get a better 1230 * @mds value next time. 1231 */ 1232 spin_lock(&inode->i_lock); 1233 goto retry; 1234 } 1235 1236 capsnap->flush_tid = ++ci->i_cap_flush_last_tid; 1237 atomic_inc(&capsnap->nref); 1238 if (!list_empty(&capsnap->flushing_item)) 1239 list_del_init(&capsnap->flushing_item); 1240 list_add_tail(&capsnap->flushing_item, 1241 &session->s_cap_snaps_flushing); 1242 spin_unlock(&inode->i_lock); 1243 1244 dout("flush_snaps %p cap_snap %p follows %lld size %llu\n", 1245 inode, capsnap, next_follows, capsnap->size); 1246 send_cap_msg(session, ceph_vino(inode).ino, 0, 1247 CEPH_CAP_OP_FLUSHSNAP, capsnap->issued, 0, 1248 capsnap->dirty, 0, capsnap->flush_tid, 0, mseq, 1249 capsnap->size, 0, 1250 &capsnap->mtime, &capsnap->atime, 1251 capsnap->time_warp_seq, 1252 capsnap->uid, capsnap->gid, capsnap->mode, 1253 0, NULL, 1254 capsnap->follows); 1255 1256 next_follows = capsnap->follows + 1; 1257 ceph_put_cap_snap(capsnap); 1258 1259 spin_lock(&inode->i_lock); 1260 goto retry; 1261 } 1262 1263 /* we flushed them all; remove this inode from the queue */ 1264 spin_lock(&mdsc->snap_flush_lock); 1265 list_del_init(&ci->i_snap_flush_item); 1266 spin_unlock(&mdsc->snap_flush_lock); 1267 1268 if (psession) 1269 *psession = session; 1270 else if (session) { 1271 mutex_unlock(&session->s_mutex); 1272 ceph_put_mds_session(session); 1273 } 1274 } 1275 1276 static void ceph_flush_snaps(struct ceph_inode_info *ci) 1277 { 1278 struct inode *inode = &ci->vfs_inode; 1279 1280 spin_lock(&inode->i_lock); 1281 __ceph_flush_snaps(ci, NULL); 1282 spin_unlock(&inode->i_lock); 1283 } 1284 1285 /* 1286 * Mark caps dirty. If inode is newly dirty, add to the global dirty 1287 * list. 1288 */ 1289 void __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask) 1290 { 1291 struct ceph_mds_client *mdsc = &ceph_client(ci->vfs_inode.i_sb)->mdsc; 1292 struct inode *inode = &ci->vfs_inode; 1293 int was = ci->i_dirty_caps; 1294 int dirty = 0; 1295 1296 dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->vfs_inode, 1297 ceph_cap_string(mask), ceph_cap_string(was), 1298 ceph_cap_string(was | mask)); 1299 ci->i_dirty_caps |= mask; 1300 if (was == 0) { 1301 dout(" inode %p now dirty\n", &ci->vfs_inode); 1302 BUG_ON(!list_empty(&ci->i_dirty_item)); 1303 spin_lock(&mdsc->cap_dirty_lock); 1304 list_add(&ci->i_dirty_item, &mdsc->cap_dirty); 1305 spin_unlock(&mdsc->cap_dirty_lock); 1306 if (ci->i_flushing_caps == 0) { 1307 igrab(inode); 1308 dirty |= I_DIRTY_SYNC; 1309 } 1310 } 1311 BUG_ON(list_empty(&ci->i_dirty_item)); 1312 if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) && 1313 (mask & CEPH_CAP_FILE_BUFFER)) 1314 dirty |= I_DIRTY_DATASYNC; 1315 if (dirty) 1316 __mark_inode_dirty(inode, dirty); 1317 __cap_delay_requeue(mdsc, ci); 1318 } 1319 1320 /* 1321 * Add dirty inode to the flushing list. Assigned a seq number so we 1322 * can wait for caps to flush without starving. 1323 * 1324 * Called under i_lock. 1325 */ 1326 static int __mark_caps_flushing(struct inode *inode, 1327 struct ceph_mds_session *session) 1328 { 1329 struct ceph_mds_client *mdsc = &ceph_client(inode->i_sb)->mdsc; 1330 struct ceph_inode_info *ci = ceph_inode(inode); 1331 int flushing; 1332 1333 BUG_ON(ci->i_dirty_caps == 0); 1334 BUG_ON(list_empty(&ci->i_dirty_item)); 1335 1336 flushing = ci->i_dirty_caps; 1337 dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n", 1338 ceph_cap_string(flushing), 1339 ceph_cap_string(ci->i_flushing_caps), 1340 ceph_cap_string(ci->i_flushing_caps | flushing)); 1341 ci->i_flushing_caps |= flushing; 1342 ci->i_dirty_caps = 0; 1343 dout(" inode %p now !dirty\n", inode); 1344 1345 spin_lock(&mdsc->cap_dirty_lock); 1346 list_del_init(&ci->i_dirty_item); 1347 1348 ci->i_cap_flush_seq = ++mdsc->cap_flush_seq; 1349 if (list_empty(&ci->i_flushing_item)) { 1350 list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing); 1351 mdsc->num_cap_flushing++; 1352 dout(" inode %p now flushing seq %lld\n", inode, 1353 ci->i_cap_flush_seq); 1354 } else { 1355 list_move_tail(&ci->i_flushing_item, &session->s_cap_flushing); 1356 dout(" inode %p now flushing (more) seq %lld\n", inode, 1357 ci->i_cap_flush_seq); 1358 } 1359 spin_unlock(&mdsc->cap_dirty_lock); 1360 1361 return flushing; 1362 } 1363 1364 /* 1365 * Swiss army knife function to examine currently used and wanted 1366 * versus held caps. Release, flush, ack revoked caps to mds as 1367 * appropriate. 1368 * 1369 * CHECK_CAPS_NODELAY - caller is delayed work and we should not delay 1370 * cap release further. 1371 * CHECK_CAPS_AUTHONLY - we should only check the auth cap 1372 * CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without 1373 * further delay. 1374 */ 1375 void ceph_check_caps(struct ceph_inode_info *ci, int flags, 1376 struct ceph_mds_session *session) 1377 { 1378 struct ceph_client *client = ceph_inode_to_client(&ci->vfs_inode); 1379 struct ceph_mds_client *mdsc = &client->mdsc; 1380 struct inode *inode = &ci->vfs_inode; 1381 struct ceph_cap *cap; 1382 int file_wanted, used; 1383 int took_snap_rwsem = 0; /* true if mdsc->snap_rwsem held */ 1384 int drop_session_lock = session ? 0 : 1; 1385 int issued, implemented, want, retain, revoking, flushing = 0; 1386 int mds = -1; /* keep track of how far we've gone through i_caps list 1387 to avoid an infinite loop on retry */ 1388 struct rb_node *p; 1389 int tried_invalidate = 0; 1390 int delayed = 0, sent = 0, force_requeue = 0, num; 1391 int queue_invalidate = 0; 1392 int is_delayed = flags & CHECK_CAPS_NODELAY; 1393 1394 /* if we are unmounting, flush any unused caps immediately. */ 1395 if (mdsc->stopping) 1396 is_delayed = 1; 1397 1398 spin_lock(&inode->i_lock); 1399 1400 if (ci->i_ceph_flags & CEPH_I_FLUSH) 1401 flags |= CHECK_CAPS_FLUSH; 1402 1403 /* flush snaps first time around only */ 1404 if (!list_empty(&ci->i_cap_snaps)) 1405 __ceph_flush_snaps(ci, &session); 1406 goto retry_locked; 1407 retry: 1408 spin_lock(&inode->i_lock); 1409 retry_locked: 1410 file_wanted = __ceph_caps_file_wanted(ci); 1411 used = __ceph_caps_used(ci); 1412 want = file_wanted | used; 1413 issued = __ceph_caps_issued(ci, &implemented); 1414 revoking = implemented & ~issued; 1415 1416 retain = want | CEPH_CAP_PIN; 1417 if (!mdsc->stopping && inode->i_nlink > 0) { 1418 if (want) { 1419 retain |= CEPH_CAP_ANY; /* be greedy */ 1420 } else { 1421 retain |= CEPH_CAP_ANY_SHARED; 1422 /* 1423 * keep RD only if we didn't have the file open RW, 1424 * because then the mds would revoke it anyway to 1425 * journal max_size=0. 1426 */ 1427 if (ci->i_max_size == 0) 1428 retain |= CEPH_CAP_ANY_RD; 1429 } 1430 } 1431 1432 dout("check_caps %p file_want %s used %s dirty %s flushing %s" 1433 " issued %s revoking %s retain %s %s%s%s\n", inode, 1434 ceph_cap_string(file_wanted), 1435 ceph_cap_string(used), ceph_cap_string(ci->i_dirty_caps), 1436 ceph_cap_string(ci->i_flushing_caps), 1437 ceph_cap_string(issued), ceph_cap_string(revoking), 1438 ceph_cap_string(retain), 1439 (flags & CHECK_CAPS_AUTHONLY) ? " AUTHONLY" : "", 1440 (flags & CHECK_CAPS_NODELAY) ? " NODELAY" : "", 1441 (flags & CHECK_CAPS_FLUSH) ? " FLUSH" : ""); 1442 1443 /* 1444 * If we no longer need to hold onto old our caps, and we may 1445 * have cached pages, but don't want them, then try to invalidate. 1446 * If we fail, it's because pages are locked.... try again later. 1447 */ 1448 if ((!is_delayed || mdsc->stopping) && 1449 ci->i_wrbuffer_ref == 0 && /* no dirty pages... */ 1450 ci->i_rdcache_gen && /* may have cached pages */ 1451 (file_wanted == 0 || /* no open files */ 1452 (revoking & CEPH_CAP_FILE_CACHE)) && /* or revoking cache */ 1453 !tried_invalidate) { 1454 u32 invalidating_gen = ci->i_rdcache_gen; 1455 int ret; 1456 1457 dout("check_caps trying to invalidate on %p\n", inode); 1458 spin_unlock(&inode->i_lock); 1459 ret = invalidate_mapping_pages(&inode->i_data, 0, -1); 1460 spin_lock(&inode->i_lock); 1461 if (ret == 0 && invalidating_gen == ci->i_rdcache_gen) { 1462 /* success. */ 1463 ci->i_rdcache_gen = 0; 1464 ci->i_rdcache_revoking = 0; 1465 } else if (revoking & CEPH_CAP_FILE_CACHE) { 1466 dout("check_caps queuing invalidate\n"); 1467 queue_invalidate = 1; 1468 ci->i_rdcache_revoking = ci->i_rdcache_gen; 1469 } else { 1470 dout("check_caps failed to invalidate pages\n"); 1471 /* we failed to invalidate pages. check these 1472 caps again later. */ 1473 force_requeue = 1; 1474 __cap_set_timeouts(mdsc, ci); 1475 } 1476 tried_invalidate = 1; 1477 goto retry_locked; 1478 } 1479 1480 num = 0; 1481 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) { 1482 cap = rb_entry(p, struct ceph_cap, ci_node); 1483 num++; 1484 1485 /* avoid looping forever */ 1486 if (mds >= cap->mds || 1487 ((flags & CHECK_CAPS_AUTHONLY) && cap != ci->i_auth_cap)) 1488 continue; 1489 1490 /* NOTE: no side-effects allowed, until we take s_mutex */ 1491 1492 revoking = cap->implemented & ~cap->issued; 1493 if (revoking) 1494 dout(" mds%d revoking %s\n", cap->mds, 1495 ceph_cap_string(revoking)); 1496 1497 if (cap == ci->i_auth_cap && 1498 (cap->issued & CEPH_CAP_FILE_WR)) { 1499 /* request larger max_size from MDS? */ 1500 if (ci->i_wanted_max_size > ci->i_max_size && 1501 ci->i_wanted_max_size > ci->i_requested_max_size) { 1502 dout("requesting new max_size\n"); 1503 goto ack; 1504 } 1505 1506 /* approaching file_max? */ 1507 if ((inode->i_size << 1) >= ci->i_max_size && 1508 (ci->i_reported_size << 1) < ci->i_max_size) { 1509 dout("i_size approaching max_size\n"); 1510 goto ack; 1511 } 1512 } 1513 /* flush anything dirty? */ 1514 if (cap == ci->i_auth_cap && (flags & CHECK_CAPS_FLUSH) && 1515 ci->i_dirty_caps) { 1516 dout("flushing dirty caps\n"); 1517 goto ack; 1518 } 1519 1520 /* completed revocation? going down and there are no caps? */ 1521 if (revoking && (revoking & used) == 0) { 1522 dout("completed revocation of %s\n", 1523 ceph_cap_string(cap->implemented & ~cap->issued)); 1524 goto ack; 1525 } 1526 1527 /* want more caps from mds? */ 1528 if (want & ~(cap->mds_wanted | cap->issued)) 1529 goto ack; 1530 1531 /* things we might delay */ 1532 if ((cap->issued & ~retain) == 0 && 1533 cap->mds_wanted == want) 1534 continue; /* nope, all good */ 1535 1536 if (is_delayed) 1537 goto ack; 1538 1539 /* delay? */ 1540 if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 && 1541 time_before(jiffies, ci->i_hold_caps_max)) { 1542 dout(" delaying issued %s -> %s, wanted %s -> %s\n", 1543 ceph_cap_string(cap->issued), 1544 ceph_cap_string(cap->issued & retain), 1545 ceph_cap_string(cap->mds_wanted), 1546 ceph_cap_string(want)); 1547 delayed++; 1548 continue; 1549 } 1550 1551 ack: 1552 if (session && session != cap->session) { 1553 dout("oops, wrong session %p mutex\n", session); 1554 mutex_unlock(&session->s_mutex); 1555 session = NULL; 1556 } 1557 if (!session) { 1558 session = cap->session; 1559 if (mutex_trylock(&session->s_mutex) == 0) { 1560 dout("inverting session/ino locks on %p\n", 1561 session); 1562 spin_unlock(&inode->i_lock); 1563 if (took_snap_rwsem) { 1564 up_read(&mdsc->snap_rwsem); 1565 took_snap_rwsem = 0; 1566 } 1567 mutex_lock(&session->s_mutex); 1568 goto retry; 1569 } 1570 } 1571 /* take snap_rwsem after session mutex */ 1572 if (!took_snap_rwsem) { 1573 if (down_read_trylock(&mdsc->snap_rwsem) == 0) { 1574 dout("inverting snap/in locks on %p\n", 1575 inode); 1576 spin_unlock(&inode->i_lock); 1577 down_read(&mdsc->snap_rwsem); 1578 took_snap_rwsem = 1; 1579 goto retry; 1580 } 1581 took_snap_rwsem = 1; 1582 } 1583 1584 if (cap == ci->i_auth_cap && ci->i_dirty_caps) 1585 flushing = __mark_caps_flushing(inode, session); 1586 1587 mds = cap->mds; /* remember mds, so we don't repeat */ 1588 sent++; 1589 1590 /* __send_cap drops i_lock */ 1591 delayed += __send_cap(mdsc, cap, CEPH_CAP_OP_UPDATE, used, want, 1592 retain, flushing, NULL); 1593 goto retry; /* retake i_lock and restart our cap scan. */ 1594 } 1595 1596 /* 1597 * Reschedule delayed caps release if we delayed anything, 1598 * otherwise cancel. 1599 */ 1600 if (delayed && is_delayed) 1601 force_requeue = 1; /* __send_cap delayed release; requeue */ 1602 if (!delayed && !is_delayed) 1603 __cap_delay_cancel(mdsc, ci); 1604 else if (!is_delayed || force_requeue) 1605 __cap_delay_requeue(mdsc, ci); 1606 1607 spin_unlock(&inode->i_lock); 1608 1609 if (queue_invalidate) 1610 ceph_queue_invalidate(inode); 1611 1612 if (session && drop_session_lock) 1613 mutex_unlock(&session->s_mutex); 1614 if (took_snap_rwsem) 1615 up_read(&mdsc->snap_rwsem); 1616 } 1617 1618 /* 1619 * Try to flush dirty caps back to the auth mds. 1620 */ 1621 static int try_flush_caps(struct inode *inode, struct ceph_mds_session *session, 1622 unsigned *flush_tid) 1623 { 1624 struct ceph_mds_client *mdsc = &ceph_client(inode->i_sb)->mdsc; 1625 struct ceph_inode_info *ci = ceph_inode(inode); 1626 int unlock_session = session ? 0 : 1; 1627 int flushing = 0; 1628 1629 retry: 1630 spin_lock(&inode->i_lock); 1631 if (ci->i_dirty_caps && ci->i_auth_cap) { 1632 struct ceph_cap *cap = ci->i_auth_cap; 1633 int used = __ceph_caps_used(ci); 1634 int want = __ceph_caps_wanted(ci); 1635 int delayed; 1636 1637 if (!session) { 1638 spin_unlock(&inode->i_lock); 1639 session = cap->session; 1640 mutex_lock(&session->s_mutex); 1641 goto retry; 1642 } 1643 BUG_ON(session != cap->session); 1644 if (cap->session->s_state < CEPH_MDS_SESSION_OPEN) 1645 goto out; 1646 1647 flushing = __mark_caps_flushing(inode, session); 1648 1649 /* __send_cap drops i_lock */ 1650 delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH, used, want, 1651 cap->issued | cap->implemented, flushing, 1652 flush_tid); 1653 if (!delayed) 1654 goto out_unlocked; 1655 1656 spin_lock(&inode->i_lock); 1657 __cap_delay_requeue(mdsc, ci); 1658 } 1659 out: 1660 spin_unlock(&inode->i_lock); 1661 out_unlocked: 1662 if (session && unlock_session) 1663 mutex_unlock(&session->s_mutex); 1664 return flushing; 1665 } 1666 1667 /* 1668 * Return true if we've flushed caps through the given flush_tid. 1669 */ 1670 static int caps_are_flushed(struct inode *inode, unsigned tid) 1671 { 1672 struct ceph_inode_info *ci = ceph_inode(inode); 1673 int dirty, i, ret = 1; 1674 1675 spin_lock(&inode->i_lock); 1676 dirty = __ceph_caps_dirty(ci); 1677 for (i = 0; i < CEPH_CAP_BITS; i++) 1678 if ((ci->i_flushing_caps & (1 << i)) && 1679 ci->i_cap_flush_tid[i] <= tid) { 1680 /* still flushing this bit */ 1681 ret = 0; 1682 break; 1683 } 1684 spin_unlock(&inode->i_lock); 1685 return ret; 1686 } 1687 1688 /* 1689 * Wait on any unsafe replies for the given inode. First wait on the 1690 * newest request, and make that the upper bound. Then, if there are 1691 * more requests, keep waiting on the oldest as long as it is still older 1692 * than the original request. 1693 */ 1694 static void sync_write_wait(struct inode *inode) 1695 { 1696 struct ceph_inode_info *ci = ceph_inode(inode); 1697 struct list_head *head = &ci->i_unsafe_writes; 1698 struct ceph_osd_request *req; 1699 u64 last_tid; 1700 1701 spin_lock(&ci->i_unsafe_lock); 1702 if (list_empty(head)) 1703 goto out; 1704 1705 /* set upper bound as _last_ entry in chain */ 1706 req = list_entry(head->prev, struct ceph_osd_request, 1707 r_unsafe_item); 1708 last_tid = req->r_tid; 1709 1710 do { 1711 ceph_osdc_get_request(req); 1712 spin_unlock(&ci->i_unsafe_lock); 1713 dout("sync_write_wait on tid %llu (until %llu)\n", 1714 req->r_tid, last_tid); 1715 wait_for_completion(&req->r_safe_completion); 1716 spin_lock(&ci->i_unsafe_lock); 1717 ceph_osdc_put_request(req); 1718 1719 /* 1720 * from here on look at first entry in chain, since we 1721 * only want to wait for anything older than last_tid 1722 */ 1723 if (list_empty(head)) 1724 break; 1725 req = list_entry(head->next, struct ceph_osd_request, 1726 r_unsafe_item); 1727 } while (req->r_tid < last_tid); 1728 out: 1729 spin_unlock(&ci->i_unsafe_lock); 1730 } 1731 1732 int ceph_fsync(struct file *file, struct dentry *dentry, int datasync) 1733 { 1734 struct inode *inode = dentry->d_inode; 1735 struct ceph_inode_info *ci = ceph_inode(inode); 1736 unsigned flush_tid; 1737 int ret; 1738 int dirty; 1739 1740 dout("fsync %p%s\n", inode, datasync ? " datasync" : ""); 1741 sync_write_wait(inode); 1742 1743 ret = filemap_write_and_wait(inode->i_mapping); 1744 if (ret < 0) 1745 return ret; 1746 1747 dirty = try_flush_caps(inode, NULL, &flush_tid); 1748 dout("fsync dirty caps are %s\n", ceph_cap_string(dirty)); 1749 1750 /* 1751 * only wait on non-file metadata writeback (the mds 1752 * can recover size and mtime, so we don't need to 1753 * wait for that) 1754 */ 1755 if (!datasync && (dirty & ~CEPH_CAP_ANY_FILE_WR)) { 1756 dout("fsync waiting for flush_tid %u\n", flush_tid); 1757 ret = wait_event_interruptible(ci->i_cap_wq, 1758 caps_are_flushed(inode, flush_tid)); 1759 } 1760 1761 dout("fsync %p%s done\n", inode, datasync ? " datasync" : ""); 1762 return ret; 1763 } 1764 1765 /* 1766 * Flush any dirty caps back to the mds. If we aren't asked to wait, 1767 * queue inode for flush but don't do so immediately, because we can 1768 * get by with fewer MDS messages if we wait for data writeback to 1769 * complete first. 1770 */ 1771 int ceph_write_inode(struct inode *inode, int wait) 1772 { 1773 struct ceph_inode_info *ci = ceph_inode(inode); 1774 unsigned flush_tid; 1775 int err = 0; 1776 int dirty; 1777 1778 dout("write_inode %p wait=%d\n", inode, wait); 1779 if (wait) { 1780 dirty = try_flush_caps(inode, NULL, &flush_tid); 1781 if (dirty) 1782 err = wait_event_interruptible(ci->i_cap_wq, 1783 caps_are_flushed(inode, flush_tid)); 1784 } else { 1785 struct ceph_mds_client *mdsc = &ceph_client(inode->i_sb)->mdsc; 1786 1787 spin_lock(&inode->i_lock); 1788 if (__ceph_caps_dirty(ci)) 1789 __cap_delay_requeue_front(mdsc, ci); 1790 spin_unlock(&inode->i_lock); 1791 } 1792 return err; 1793 } 1794 1795 /* 1796 * After a recovering MDS goes active, we need to resend any caps 1797 * we were flushing. 1798 * 1799 * Caller holds session->s_mutex. 1800 */ 1801 static void kick_flushing_capsnaps(struct ceph_mds_client *mdsc, 1802 struct ceph_mds_session *session) 1803 { 1804 struct ceph_cap_snap *capsnap; 1805 1806 dout("kick_flushing_capsnaps mds%d\n", session->s_mds); 1807 list_for_each_entry(capsnap, &session->s_cap_snaps_flushing, 1808 flushing_item) { 1809 struct ceph_inode_info *ci = capsnap->ci; 1810 struct inode *inode = &ci->vfs_inode; 1811 struct ceph_cap *cap; 1812 1813 spin_lock(&inode->i_lock); 1814 cap = ci->i_auth_cap; 1815 if (cap && cap->session == session) { 1816 dout("kick_flushing_caps %p cap %p capsnap %p\n", inode, 1817 cap, capsnap); 1818 __ceph_flush_snaps(ci, &session); 1819 } else { 1820 pr_err("%p auth cap %p not mds%d ???\n", inode, 1821 cap, session->s_mds); 1822 spin_unlock(&inode->i_lock); 1823 } 1824 } 1825 } 1826 1827 void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc, 1828 struct ceph_mds_session *session) 1829 { 1830 struct ceph_inode_info *ci; 1831 1832 kick_flushing_capsnaps(mdsc, session); 1833 1834 dout("kick_flushing_caps mds%d\n", session->s_mds); 1835 list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) { 1836 struct inode *inode = &ci->vfs_inode; 1837 struct ceph_cap *cap; 1838 int delayed = 0; 1839 1840 spin_lock(&inode->i_lock); 1841 cap = ci->i_auth_cap; 1842 if (cap && cap->session == session) { 1843 dout("kick_flushing_caps %p cap %p %s\n", inode, 1844 cap, ceph_cap_string(ci->i_flushing_caps)); 1845 delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH, 1846 __ceph_caps_used(ci), 1847 __ceph_caps_wanted(ci), 1848 cap->issued | cap->implemented, 1849 ci->i_flushing_caps, NULL); 1850 if (delayed) { 1851 spin_lock(&inode->i_lock); 1852 __cap_delay_requeue(mdsc, ci); 1853 spin_unlock(&inode->i_lock); 1854 } 1855 } else { 1856 pr_err("%p auth cap %p not mds%d ???\n", inode, 1857 cap, session->s_mds); 1858 spin_unlock(&inode->i_lock); 1859 } 1860 } 1861 } 1862 1863 1864 /* 1865 * Take references to capabilities we hold, so that we don't release 1866 * them to the MDS prematurely. 1867 * 1868 * Protected by i_lock. 1869 */ 1870 static void __take_cap_refs(struct ceph_inode_info *ci, int got) 1871 { 1872 if (got & CEPH_CAP_PIN) 1873 ci->i_pin_ref++; 1874 if (got & CEPH_CAP_FILE_RD) 1875 ci->i_rd_ref++; 1876 if (got & CEPH_CAP_FILE_CACHE) 1877 ci->i_rdcache_ref++; 1878 if (got & CEPH_CAP_FILE_WR) 1879 ci->i_wr_ref++; 1880 if (got & CEPH_CAP_FILE_BUFFER) { 1881 if (ci->i_wrbuffer_ref == 0) 1882 igrab(&ci->vfs_inode); 1883 ci->i_wrbuffer_ref++; 1884 dout("__take_cap_refs %p wrbuffer %d -> %d (?)\n", 1885 &ci->vfs_inode, ci->i_wrbuffer_ref-1, ci->i_wrbuffer_ref); 1886 } 1887 } 1888 1889 /* 1890 * Try to grab cap references. Specify those refs we @want, and the 1891 * minimal set we @need. Also include the larger offset we are writing 1892 * to (when applicable), and check against max_size here as well. 1893 * Note that caller is responsible for ensuring max_size increases are 1894 * requested from the MDS. 1895 */ 1896 static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want, 1897 int *got, loff_t endoff, int *check_max, int *err) 1898 { 1899 struct inode *inode = &ci->vfs_inode; 1900 int ret = 0; 1901 int have, implemented; 1902 1903 dout("get_cap_refs %p need %s want %s\n", inode, 1904 ceph_cap_string(need), ceph_cap_string(want)); 1905 spin_lock(&inode->i_lock); 1906 1907 /* make sure we _have_ some caps! */ 1908 if (!__ceph_is_any_caps(ci)) { 1909 dout("get_cap_refs %p no real caps\n", inode); 1910 *err = -EBADF; 1911 ret = 1; 1912 goto out; 1913 } 1914 1915 if (need & CEPH_CAP_FILE_WR) { 1916 if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) { 1917 dout("get_cap_refs %p endoff %llu > maxsize %llu\n", 1918 inode, endoff, ci->i_max_size); 1919 if (endoff > ci->i_wanted_max_size) { 1920 *check_max = 1; 1921 ret = 1; 1922 } 1923 goto out; 1924 } 1925 /* 1926 * If a sync write is in progress, we must wait, so that we 1927 * can get a final snapshot value for size+mtime. 1928 */ 1929 if (__ceph_have_pending_cap_snap(ci)) { 1930 dout("get_cap_refs %p cap_snap_pending\n", inode); 1931 goto out; 1932 } 1933 } 1934 have = __ceph_caps_issued(ci, &implemented); 1935 1936 /* 1937 * disallow writes while a truncate is pending 1938 */ 1939 if (ci->i_truncate_pending) 1940 have &= ~CEPH_CAP_FILE_WR; 1941 1942 if ((have & need) == need) { 1943 /* 1944 * Look at (implemented & ~have & not) so that we keep waiting 1945 * on transition from wanted -> needed caps. This is needed 1946 * for WRBUFFER|WR -> WR to avoid a new WR sync write from 1947 * going before a prior buffered writeback happens. 1948 */ 1949 int not = want & ~(have & need); 1950 int revoking = implemented & ~have; 1951 dout("get_cap_refs %p have %s but not %s (revoking %s)\n", 1952 inode, ceph_cap_string(have), ceph_cap_string(not), 1953 ceph_cap_string(revoking)); 1954 if ((revoking & not) == 0) { 1955 *got = need | (have & want); 1956 __take_cap_refs(ci, *got); 1957 ret = 1; 1958 } 1959 } else { 1960 dout("get_cap_refs %p have %s needed %s\n", inode, 1961 ceph_cap_string(have), ceph_cap_string(need)); 1962 } 1963 out: 1964 spin_unlock(&inode->i_lock); 1965 dout("get_cap_refs %p ret %d got %s\n", inode, 1966 ret, ceph_cap_string(*got)); 1967 return ret; 1968 } 1969 1970 /* 1971 * Check the offset we are writing up to against our current 1972 * max_size. If necessary, tell the MDS we want to write to 1973 * a larger offset. 1974 */ 1975 static void check_max_size(struct inode *inode, loff_t endoff) 1976 { 1977 struct ceph_inode_info *ci = ceph_inode(inode); 1978 int check = 0; 1979 1980 /* do we need to explicitly request a larger max_size? */ 1981 spin_lock(&inode->i_lock); 1982 if ((endoff >= ci->i_max_size || 1983 endoff > (inode->i_size << 1)) && 1984 endoff > ci->i_wanted_max_size) { 1985 dout("write %p at large endoff %llu, req max_size\n", 1986 inode, endoff); 1987 ci->i_wanted_max_size = endoff; 1988 check = 1; 1989 } 1990 spin_unlock(&inode->i_lock); 1991 if (check) 1992 ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL); 1993 } 1994 1995 /* 1996 * Wait for caps, and take cap references. If we can't get a WR cap 1997 * due to a small max_size, make sure we check_max_size (and possibly 1998 * ask the mds) so we don't get hung up indefinitely. 1999 */ 2000 int ceph_get_caps(struct ceph_inode_info *ci, int need, int want, int *got, 2001 loff_t endoff) 2002 { 2003 int check_max, ret, err; 2004 2005 retry: 2006 if (endoff > 0) 2007 check_max_size(&ci->vfs_inode, endoff); 2008 check_max = 0; 2009 err = 0; 2010 ret = wait_event_interruptible(ci->i_cap_wq, 2011 try_get_cap_refs(ci, need, want, 2012 got, endoff, 2013 &check_max, &err)); 2014 if (err) 2015 ret = err; 2016 if (check_max) 2017 goto retry; 2018 return ret; 2019 } 2020 2021 /* 2022 * Take cap refs. Caller must already know we hold at least one ref 2023 * on the caps in question or we don't know this is safe. 2024 */ 2025 void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps) 2026 { 2027 spin_lock(&ci->vfs_inode.i_lock); 2028 __take_cap_refs(ci, caps); 2029 spin_unlock(&ci->vfs_inode.i_lock); 2030 } 2031 2032 /* 2033 * Release cap refs. 2034 * 2035 * If we released the last ref on any given cap, call ceph_check_caps 2036 * to release (or schedule a release). 2037 * 2038 * If we are releasing a WR cap (from a sync write), finalize any affected 2039 * cap_snap, and wake up any waiters. 2040 */ 2041 void ceph_put_cap_refs(struct ceph_inode_info *ci, int had) 2042 { 2043 struct inode *inode = &ci->vfs_inode; 2044 int last = 0, put = 0, flushsnaps = 0, wake = 0; 2045 struct ceph_cap_snap *capsnap; 2046 2047 spin_lock(&inode->i_lock); 2048 if (had & CEPH_CAP_PIN) 2049 --ci->i_pin_ref; 2050 if (had & CEPH_CAP_FILE_RD) 2051 if (--ci->i_rd_ref == 0) 2052 last++; 2053 if (had & CEPH_CAP_FILE_CACHE) 2054 if (--ci->i_rdcache_ref == 0) 2055 last++; 2056 if (had & CEPH_CAP_FILE_BUFFER) { 2057 if (--ci->i_wrbuffer_ref == 0) { 2058 last++; 2059 put++; 2060 } 2061 dout("put_cap_refs %p wrbuffer %d -> %d (?)\n", 2062 inode, ci->i_wrbuffer_ref+1, ci->i_wrbuffer_ref); 2063 } 2064 if (had & CEPH_CAP_FILE_WR) 2065 if (--ci->i_wr_ref == 0) { 2066 last++; 2067 if (!list_empty(&ci->i_cap_snaps)) { 2068 capsnap = list_first_entry(&ci->i_cap_snaps, 2069 struct ceph_cap_snap, 2070 ci_item); 2071 if (capsnap->writing) { 2072 capsnap->writing = 0; 2073 flushsnaps = 2074 __ceph_finish_cap_snap(ci, 2075 capsnap); 2076 wake = 1; 2077 } 2078 } 2079 } 2080 spin_unlock(&inode->i_lock); 2081 2082 dout("put_cap_refs %p had %s %s\n", inode, ceph_cap_string(had), 2083 last ? "last" : ""); 2084 2085 if (last && !flushsnaps) 2086 ceph_check_caps(ci, 0, NULL); 2087 else if (flushsnaps) 2088 ceph_flush_snaps(ci); 2089 if (wake) 2090 wake_up(&ci->i_cap_wq); 2091 if (put) 2092 iput(inode); 2093 } 2094 2095 /* 2096 * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap 2097 * context. Adjust per-snap dirty page accounting as appropriate. 2098 * Once all dirty data for a cap_snap is flushed, flush snapped file 2099 * metadata back to the MDS. If we dropped the last ref, call 2100 * ceph_check_caps. 2101 */ 2102 void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr, 2103 struct ceph_snap_context *snapc) 2104 { 2105 struct inode *inode = &ci->vfs_inode; 2106 int last = 0; 2107 int last_snap = 0; 2108 int found = 0; 2109 struct ceph_cap_snap *capsnap = NULL; 2110 2111 spin_lock(&inode->i_lock); 2112 ci->i_wrbuffer_ref -= nr; 2113 last = !ci->i_wrbuffer_ref; 2114 2115 if (ci->i_head_snapc == snapc) { 2116 ci->i_wrbuffer_ref_head -= nr; 2117 if (!ci->i_wrbuffer_ref_head) { 2118 ceph_put_snap_context(ci->i_head_snapc); 2119 ci->i_head_snapc = NULL; 2120 } 2121 dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n", 2122 inode, 2123 ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr, 2124 ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head, 2125 last ? " LAST" : ""); 2126 } else { 2127 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) { 2128 if (capsnap->context == snapc) { 2129 found = 1; 2130 capsnap->dirty_pages -= nr; 2131 last_snap = !capsnap->dirty_pages; 2132 break; 2133 } 2134 } 2135 BUG_ON(!found); 2136 dout("put_wrbuffer_cap_refs on %p cap_snap %p " 2137 " snap %lld %d/%d -> %d/%d %s%s\n", 2138 inode, capsnap, capsnap->context->seq, 2139 ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr, 2140 ci->i_wrbuffer_ref, capsnap->dirty_pages, 2141 last ? " (wrbuffer last)" : "", 2142 last_snap ? " (capsnap last)" : ""); 2143 } 2144 2145 spin_unlock(&inode->i_lock); 2146 2147 if (last) { 2148 ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL); 2149 iput(inode); 2150 } else if (last_snap) { 2151 ceph_flush_snaps(ci); 2152 wake_up(&ci->i_cap_wq); 2153 } 2154 } 2155 2156 /* 2157 * Handle a cap GRANT message from the MDS. (Note that a GRANT may 2158 * actually be a revocation if it specifies a smaller cap set.) 2159 * 2160 * caller holds s_mutex. 2161 * return value: 2162 * 0 - ok 2163 * 1 - check_caps on auth cap only (writeback) 2164 * 2 - check_caps (ack revoke) 2165 */ 2166 static int handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant, 2167 struct ceph_mds_session *session, 2168 struct ceph_cap *cap, 2169 struct ceph_buffer *xattr_buf) 2170 __releases(inode->i_lock) 2171 2172 { 2173 struct ceph_inode_info *ci = ceph_inode(inode); 2174 int mds = session->s_mds; 2175 int seq = le32_to_cpu(grant->seq); 2176 int newcaps = le32_to_cpu(grant->caps); 2177 int issued, implemented, used, wanted, dirty; 2178 u64 size = le64_to_cpu(grant->size); 2179 u64 max_size = le64_to_cpu(grant->max_size); 2180 struct timespec mtime, atime, ctime; 2181 int reply = 0; 2182 int wake = 0; 2183 int writeback = 0; 2184 int revoked_rdcache = 0; 2185 int queue_invalidate = 0; 2186 int tried_invalidate = 0; 2187 int ret; 2188 2189 dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n", 2190 inode, cap, mds, seq, ceph_cap_string(newcaps)); 2191 dout(" size %llu max_size %llu, i_size %llu\n", size, max_size, 2192 inode->i_size); 2193 2194 /* 2195 * If CACHE is being revoked, and we have no dirty buffers, 2196 * try to invalidate (once). (If there are dirty buffers, we 2197 * will invalidate _after_ writeback.) 2198 */ 2199 restart: 2200 if (((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) && 2201 !ci->i_wrbuffer_ref && !tried_invalidate) { 2202 dout("CACHE invalidation\n"); 2203 spin_unlock(&inode->i_lock); 2204 tried_invalidate = 1; 2205 2206 ret = invalidate_mapping_pages(&inode->i_data, 0, -1); 2207 spin_lock(&inode->i_lock); 2208 if (ret < 0) { 2209 /* there were locked pages.. invalidate later 2210 in a separate thread. */ 2211 if (ci->i_rdcache_revoking != ci->i_rdcache_gen) { 2212 queue_invalidate = 1; 2213 ci->i_rdcache_revoking = ci->i_rdcache_gen; 2214 } 2215 } else { 2216 /* we successfully invalidated those pages */ 2217 revoked_rdcache = 1; 2218 ci->i_rdcache_gen = 0; 2219 ci->i_rdcache_revoking = 0; 2220 } 2221 goto restart; 2222 } 2223 2224 /* side effects now are allowed */ 2225 2226 issued = __ceph_caps_issued(ci, &implemented); 2227 issued |= implemented | __ceph_caps_dirty(ci); 2228 2229 cap->cap_gen = session->s_cap_gen; 2230 2231 __check_cap_issue(ci, cap, newcaps); 2232 2233 if ((issued & CEPH_CAP_AUTH_EXCL) == 0) { 2234 inode->i_mode = le32_to_cpu(grant->mode); 2235 inode->i_uid = le32_to_cpu(grant->uid); 2236 inode->i_gid = le32_to_cpu(grant->gid); 2237 dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode, 2238 inode->i_uid, inode->i_gid); 2239 } 2240 2241 if ((issued & CEPH_CAP_LINK_EXCL) == 0) 2242 inode->i_nlink = le32_to_cpu(grant->nlink); 2243 2244 if ((issued & CEPH_CAP_XATTR_EXCL) == 0 && grant->xattr_len) { 2245 int len = le32_to_cpu(grant->xattr_len); 2246 u64 version = le64_to_cpu(grant->xattr_version); 2247 2248 if (version > ci->i_xattrs.version) { 2249 dout(" got new xattrs v%llu on %p len %d\n", 2250 version, inode, len); 2251 if (ci->i_xattrs.blob) 2252 ceph_buffer_put(ci->i_xattrs.blob); 2253 ci->i_xattrs.blob = ceph_buffer_get(xattr_buf); 2254 ci->i_xattrs.version = version; 2255 } 2256 } 2257 2258 /* size/ctime/mtime/atime? */ 2259 ceph_fill_file_size(inode, issued, 2260 le32_to_cpu(grant->truncate_seq), 2261 le64_to_cpu(grant->truncate_size), size); 2262 ceph_decode_timespec(&mtime, &grant->mtime); 2263 ceph_decode_timespec(&atime, &grant->atime); 2264 ceph_decode_timespec(&ctime, &grant->ctime); 2265 ceph_fill_file_time(inode, issued, 2266 le32_to_cpu(grant->time_warp_seq), &ctime, &mtime, 2267 &atime); 2268 2269 /* max size increase? */ 2270 if (max_size != ci->i_max_size) { 2271 dout("max_size %lld -> %llu\n", ci->i_max_size, max_size); 2272 ci->i_max_size = max_size; 2273 if (max_size >= ci->i_wanted_max_size) { 2274 ci->i_wanted_max_size = 0; /* reset */ 2275 ci->i_requested_max_size = 0; 2276 } 2277 wake = 1; 2278 } 2279 2280 /* check cap bits */ 2281 wanted = __ceph_caps_wanted(ci); 2282 used = __ceph_caps_used(ci); 2283 dirty = __ceph_caps_dirty(ci); 2284 dout(" my wanted = %s, used = %s, dirty %s\n", 2285 ceph_cap_string(wanted), 2286 ceph_cap_string(used), 2287 ceph_cap_string(dirty)); 2288 if (wanted != le32_to_cpu(grant->wanted)) { 2289 dout("mds wanted %s -> %s\n", 2290 ceph_cap_string(le32_to_cpu(grant->wanted)), 2291 ceph_cap_string(wanted)); 2292 grant->wanted = cpu_to_le32(wanted); 2293 } 2294 2295 cap->seq = seq; 2296 2297 /* file layout may have changed */ 2298 ci->i_layout = grant->layout; 2299 2300 /* revocation, grant, or no-op? */ 2301 if (cap->issued & ~newcaps) { 2302 dout("revocation: %s -> %s\n", ceph_cap_string(cap->issued), 2303 ceph_cap_string(newcaps)); 2304 if ((used & ~newcaps) & CEPH_CAP_FILE_BUFFER) 2305 writeback = 1; /* will delay ack */ 2306 else if (dirty & ~newcaps) 2307 reply = 1; /* initiate writeback in check_caps */ 2308 else if (((used & ~newcaps) & CEPH_CAP_FILE_CACHE) == 0 || 2309 revoked_rdcache) 2310 reply = 2; /* send revoke ack in check_caps */ 2311 cap->issued = newcaps; 2312 } else if (cap->issued == newcaps) { 2313 dout("caps unchanged: %s -> %s\n", 2314 ceph_cap_string(cap->issued), ceph_cap_string(newcaps)); 2315 } else { 2316 dout("grant: %s -> %s\n", ceph_cap_string(cap->issued), 2317 ceph_cap_string(newcaps)); 2318 cap->issued = newcaps; 2319 cap->implemented |= newcaps; /* add bits only, to 2320 * avoid stepping on a 2321 * pending revocation */ 2322 wake = 1; 2323 } 2324 2325 spin_unlock(&inode->i_lock); 2326 if (writeback) 2327 /* 2328 * queue inode for writeback: we can't actually call 2329 * filemap_write_and_wait, etc. from message handler 2330 * context. 2331 */ 2332 ceph_queue_writeback(inode); 2333 if (queue_invalidate) 2334 ceph_queue_invalidate(inode); 2335 if (wake) 2336 wake_up(&ci->i_cap_wq); 2337 return reply; 2338 } 2339 2340 /* 2341 * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the 2342 * MDS has been safely committed. 2343 */ 2344 static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid, 2345 struct ceph_mds_caps *m, 2346 struct ceph_mds_session *session, 2347 struct ceph_cap *cap) 2348 __releases(inode->i_lock) 2349 { 2350 struct ceph_inode_info *ci = ceph_inode(inode); 2351 struct ceph_mds_client *mdsc = &ceph_client(inode->i_sb)->mdsc; 2352 unsigned seq = le32_to_cpu(m->seq); 2353 int dirty = le32_to_cpu(m->dirty); 2354 int cleaned = 0; 2355 int drop = 0; 2356 int i; 2357 2358 for (i = 0; i < CEPH_CAP_BITS; i++) 2359 if ((dirty & (1 << i)) && 2360 flush_tid == ci->i_cap_flush_tid[i]) 2361 cleaned |= 1 << i; 2362 2363 dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s," 2364 " flushing %s -> %s\n", 2365 inode, session->s_mds, seq, ceph_cap_string(dirty), 2366 ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps), 2367 ceph_cap_string(ci->i_flushing_caps & ~cleaned)); 2368 2369 if (ci->i_flushing_caps == (ci->i_flushing_caps & ~cleaned)) 2370 goto out; 2371 2372 ci->i_flushing_caps &= ~cleaned; 2373 2374 spin_lock(&mdsc->cap_dirty_lock); 2375 if (ci->i_flushing_caps == 0) { 2376 list_del_init(&ci->i_flushing_item); 2377 if (!list_empty(&session->s_cap_flushing)) 2378 dout(" mds%d still flushing cap on %p\n", 2379 session->s_mds, 2380 &list_entry(session->s_cap_flushing.next, 2381 struct ceph_inode_info, 2382 i_flushing_item)->vfs_inode); 2383 mdsc->num_cap_flushing--; 2384 wake_up(&mdsc->cap_flushing_wq); 2385 dout(" inode %p now !flushing\n", inode); 2386 2387 if (ci->i_dirty_caps == 0) { 2388 dout(" inode %p now clean\n", inode); 2389 BUG_ON(!list_empty(&ci->i_dirty_item)); 2390 drop = 1; 2391 } else { 2392 BUG_ON(list_empty(&ci->i_dirty_item)); 2393 } 2394 } 2395 spin_unlock(&mdsc->cap_dirty_lock); 2396 wake_up(&ci->i_cap_wq); 2397 2398 out: 2399 spin_unlock(&inode->i_lock); 2400 if (drop) 2401 iput(inode); 2402 } 2403 2404 /* 2405 * Handle FLUSHSNAP_ACK. MDS has flushed snap data to disk and we can 2406 * throw away our cap_snap. 2407 * 2408 * Caller hold s_mutex. 2409 */ 2410 static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid, 2411 struct ceph_mds_caps *m, 2412 struct ceph_mds_session *session) 2413 { 2414 struct ceph_inode_info *ci = ceph_inode(inode); 2415 u64 follows = le64_to_cpu(m->snap_follows); 2416 struct ceph_cap_snap *capsnap; 2417 int drop = 0; 2418 2419 dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n", 2420 inode, ci, session->s_mds, follows); 2421 2422 spin_lock(&inode->i_lock); 2423 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) { 2424 if (capsnap->follows == follows) { 2425 if (capsnap->flush_tid != flush_tid) { 2426 dout(" cap_snap %p follows %lld tid %lld !=" 2427 " %lld\n", capsnap, follows, 2428 flush_tid, capsnap->flush_tid); 2429 break; 2430 } 2431 WARN_ON(capsnap->dirty_pages || capsnap->writing); 2432 dout(" removing cap_snap %p follows %lld\n", 2433 capsnap, follows); 2434 ceph_put_snap_context(capsnap->context); 2435 list_del(&capsnap->ci_item); 2436 list_del(&capsnap->flushing_item); 2437 ceph_put_cap_snap(capsnap); 2438 drop = 1; 2439 break; 2440 } else { 2441 dout(" skipping cap_snap %p follows %lld\n", 2442 capsnap, capsnap->follows); 2443 } 2444 } 2445 spin_unlock(&inode->i_lock); 2446 if (drop) 2447 iput(inode); 2448 } 2449 2450 /* 2451 * Handle TRUNC from MDS, indicating file truncation. 2452 * 2453 * caller hold s_mutex. 2454 */ 2455 static void handle_cap_trunc(struct inode *inode, 2456 struct ceph_mds_caps *trunc, 2457 struct ceph_mds_session *session) 2458 __releases(inode->i_lock) 2459 { 2460 struct ceph_inode_info *ci = ceph_inode(inode); 2461 int mds = session->s_mds; 2462 int seq = le32_to_cpu(trunc->seq); 2463 u32 truncate_seq = le32_to_cpu(trunc->truncate_seq); 2464 u64 truncate_size = le64_to_cpu(trunc->truncate_size); 2465 u64 size = le64_to_cpu(trunc->size); 2466 int implemented = 0; 2467 int dirty = __ceph_caps_dirty(ci); 2468 int issued = __ceph_caps_issued(ceph_inode(inode), &implemented); 2469 int queue_trunc = 0; 2470 2471 issued |= implemented | dirty; 2472 2473 dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n", 2474 inode, mds, seq, truncate_size, truncate_seq); 2475 queue_trunc = ceph_fill_file_size(inode, issued, 2476 truncate_seq, truncate_size, size); 2477 spin_unlock(&inode->i_lock); 2478 2479 if (queue_trunc) 2480 ceph_queue_vmtruncate(inode); 2481 } 2482 2483 /* 2484 * Handle EXPORT from MDS. Cap is being migrated _from_ this mds to a 2485 * different one. If we are the most recent migration we've seen (as 2486 * indicated by mseq), make note of the migrating cap bits for the 2487 * duration (until we see the corresponding IMPORT). 2488 * 2489 * caller holds s_mutex 2490 */ 2491 static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex, 2492 struct ceph_mds_session *session) 2493 { 2494 struct ceph_inode_info *ci = ceph_inode(inode); 2495 int mds = session->s_mds; 2496 unsigned mseq = le32_to_cpu(ex->migrate_seq); 2497 struct ceph_cap *cap = NULL, *t; 2498 struct rb_node *p; 2499 int remember = 1; 2500 2501 dout("handle_cap_export inode %p ci %p mds%d mseq %d\n", 2502 inode, ci, mds, mseq); 2503 2504 spin_lock(&inode->i_lock); 2505 2506 /* make sure we haven't seen a higher mseq */ 2507 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) { 2508 t = rb_entry(p, struct ceph_cap, ci_node); 2509 if (ceph_seq_cmp(t->mseq, mseq) > 0) { 2510 dout(" higher mseq on cap from mds%d\n", 2511 t->session->s_mds); 2512 remember = 0; 2513 } 2514 if (t->session->s_mds == mds) 2515 cap = t; 2516 } 2517 2518 if (cap) { 2519 if (remember) { 2520 /* make note */ 2521 ci->i_cap_exporting_mds = mds; 2522 ci->i_cap_exporting_mseq = mseq; 2523 ci->i_cap_exporting_issued = cap->issued; 2524 } 2525 __ceph_remove_cap(cap); 2526 } else { 2527 WARN_ON(!cap); 2528 } 2529 2530 spin_unlock(&inode->i_lock); 2531 } 2532 2533 /* 2534 * Handle cap IMPORT. If there are temp bits from an older EXPORT, 2535 * clean them up. 2536 * 2537 * caller holds s_mutex. 2538 */ 2539 static void handle_cap_import(struct ceph_mds_client *mdsc, 2540 struct inode *inode, struct ceph_mds_caps *im, 2541 struct ceph_mds_session *session, 2542 void *snaptrace, int snaptrace_len) 2543 { 2544 struct ceph_inode_info *ci = ceph_inode(inode); 2545 int mds = session->s_mds; 2546 unsigned issued = le32_to_cpu(im->caps); 2547 unsigned wanted = le32_to_cpu(im->wanted); 2548 unsigned seq = le32_to_cpu(im->seq); 2549 unsigned mseq = le32_to_cpu(im->migrate_seq); 2550 u64 realmino = le64_to_cpu(im->realm); 2551 u64 cap_id = le64_to_cpu(im->cap_id); 2552 2553 if (ci->i_cap_exporting_mds >= 0 && 2554 ceph_seq_cmp(ci->i_cap_exporting_mseq, mseq) < 0) { 2555 dout("handle_cap_import inode %p ci %p mds%d mseq %d" 2556 " - cleared exporting from mds%d\n", 2557 inode, ci, mds, mseq, 2558 ci->i_cap_exporting_mds); 2559 ci->i_cap_exporting_issued = 0; 2560 ci->i_cap_exporting_mseq = 0; 2561 ci->i_cap_exporting_mds = -1; 2562 } else { 2563 dout("handle_cap_import inode %p ci %p mds%d mseq %d\n", 2564 inode, ci, mds, mseq); 2565 } 2566 2567 down_write(&mdsc->snap_rwsem); 2568 ceph_update_snap_trace(mdsc, snaptrace, snaptrace+snaptrace_len, 2569 false); 2570 downgrade_write(&mdsc->snap_rwsem); 2571 ceph_add_cap(inode, session, cap_id, -1, 2572 issued, wanted, seq, mseq, realmino, CEPH_CAP_FLAG_AUTH, 2573 NULL /* no caps context */); 2574 try_flush_caps(inode, session, NULL); 2575 up_read(&mdsc->snap_rwsem); 2576 } 2577 2578 /* 2579 * Handle a caps message from the MDS. 2580 * 2581 * Identify the appropriate session, inode, and call the right handler 2582 * based on the cap op. 2583 */ 2584 void ceph_handle_caps(struct ceph_mds_session *session, 2585 struct ceph_msg *msg) 2586 { 2587 struct ceph_mds_client *mdsc = session->s_mdsc; 2588 struct super_block *sb = mdsc->client->sb; 2589 struct inode *inode; 2590 struct ceph_cap *cap; 2591 struct ceph_mds_caps *h; 2592 int mds = le64_to_cpu(msg->hdr.src.name.num); 2593 int op; 2594 u32 seq; 2595 struct ceph_vino vino; 2596 u64 cap_id; 2597 u64 size, max_size; 2598 u64 tid; 2599 int check_caps = 0; 2600 int r; 2601 2602 dout("handle_caps from mds%d\n", mds); 2603 2604 /* decode */ 2605 tid = le64_to_cpu(msg->hdr.tid); 2606 if (msg->front.iov_len < sizeof(*h)) 2607 goto bad; 2608 h = msg->front.iov_base; 2609 op = le32_to_cpu(h->op); 2610 vino.ino = le64_to_cpu(h->ino); 2611 vino.snap = CEPH_NOSNAP; 2612 cap_id = le64_to_cpu(h->cap_id); 2613 seq = le32_to_cpu(h->seq); 2614 size = le64_to_cpu(h->size); 2615 max_size = le64_to_cpu(h->max_size); 2616 2617 mutex_lock(&session->s_mutex); 2618 session->s_seq++; 2619 dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq, 2620 (unsigned)seq); 2621 2622 /* lookup ino */ 2623 inode = ceph_find_inode(sb, vino); 2624 dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino, 2625 vino.snap, inode); 2626 if (!inode) { 2627 dout(" i don't have ino %llx\n", vino.ino); 2628 goto done; 2629 } 2630 2631 /* these will work even if we don't have a cap yet */ 2632 switch (op) { 2633 case CEPH_CAP_OP_FLUSHSNAP_ACK: 2634 handle_cap_flushsnap_ack(inode, tid, h, session); 2635 goto done; 2636 2637 case CEPH_CAP_OP_EXPORT: 2638 handle_cap_export(inode, h, session); 2639 goto done; 2640 2641 case CEPH_CAP_OP_IMPORT: 2642 handle_cap_import(mdsc, inode, h, session, 2643 msg->middle, 2644 le32_to_cpu(h->snap_trace_len)); 2645 check_caps = 1; /* we may have sent a RELEASE to the old auth */ 2646 goto done; 2647 } 2648 2649 /* the rest require a cap */ 2650 spin_lock(&inode->i_lock); 2651 cap = __get_cap_for_mds(ceph_inode(inode), mds); 2652 if (!cap) { 2653 dout("no cap on %p ino %llx.%llx from mds%d, releasing\n", 2654 inode, ceph_ino(inode), ceph_snap(inode), mds); 2655 spin_unlock(&inode->i_lock); 2656 goto done; 2657 } 2658 2659 /* note that each of these drops i_lock for us */ 2660 switch (op) { 2661 case CEPH_CAP_OP_REVOKE: 2662 case CEPH_CAP_OP_GRANT: 2663 r = handle_cap_grant(inode, h, session, cap, msg->middle); 2664 if (r == 1) 2665 ceph_check_caps(ceph_inode(inode), 2666 CHECK_CAPS_NODELAY|CHECK_CAPS_AUTHONLY, 2667 session); 2668 else if (r == 2) 2669 ceph_check_caps(ceph_inode(inode), 2670 CHECK_CAPS_NODELAY, 2671 session); 2672 break; 2673 2674 case CEPH_CAP_OP_FLUSH_ACK: 2675 handle_cap_flush_ack(inode, tid, h, session, cap); 2676 break; 2677 2678 case CEPH_CAP_OP_TRUNC: 2679 handle_cap_trunc(inode, h, session); 2680 break; 2681 2682 default: 2683 spin_unlock(&inode->i_lock); 2684 pr_err("ceph_handle_caps: unknown cap op %d %s\n", op, 2685 ceph_cap_op_name(op)); 2686 } 2687 2688 done: 2689 mutex_unlock(&session->s_mutex); 2690 2691 if (check_caps) 2692 ceph_check_caps(ceph_inode(inode), CHECK_CAPS_NODELAY, NULL); 2693 if (inode) 2694 iput(inode); 2695 return; 2696 2697 bad: 2698 pr_err("ceph_handle_caps: corrupt message\n"); 2699 ceph_msg_dump(msg); 2700 return; 2701 } 2702 2703 /* 2704 * Delayed work handler to process end of delayed cap release LRU list. 2705 */ 2706 void ceph_check_delayed_caps(struct ceph_mds_client *mdsc) 2707 { 2708 struct ceph_inode_info *ci; 2709 int flags = CHECK_CAPS_NODELAY; 2710 2711 dout("check_delayed_caps\n"); 2712 while (1) { 2713 spin_lock(&mdsc->cap_delay_lock); 2714 if (list_empty(&mdsc->cap_delay_list)) 2715 break; 2716 ci = list_first_entry(&mdsc->cap_delay_list, 2717 struct ceph_inode_info, 2718 i_cap_delay_list); 2719 if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 && 2720 time_before(jiffies, ci->i_hold_caps_max)) 2721 break; 2722 list_del_init(&ci->i_cap_delay_list); 2723 spin_unlock(&mdsc->cap_delay_lock); 2724 dout("check_delayed_caps on %p\n", &ci->vfs_inode); 2725 ceph_check_caps(ci, flags, NULL); 2726 } 2727 spin_unlock(&mdsc->cap_delay_lock); 2728 } 2729 2730 /* 2731 * Flush all dirty caps to the mds 2732 */ 2733 void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc) 2734 { 2735 struct ceph_inode_info *ci; 2736 struct inode *inode; 2737 2738 dout("flush_dirty_caps\n"); 2739 spin_lock(&mdsc->cap_dirty_lock); 2740 while (!list_empty(&mdsc->cap_dirty)) { 2741 ci = list_first_entry(&mdsc->cap_dirty, 2742 struct ceph_inode_info, 2743 i_dirty_item); 2744 inode = igrab(&ci->vfs_inode); 2745 spin_unlock(&mdsc->cap_dirty_lock); 2746 if (inode) { 2747 ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_FLUSH, 2748 NULL); 2749 iput(inode); 2750 } 2751 spin_lock(&mdsc->cap_dirty_lock); 2752 } 2753 spin_unlock(&mdsc->cap_dirty_lock); 2754 } 2755 2756 /* 2757 * Drop open file reference. If we were the last open file, 2758 * we may need to release capabilities to the MDS (or schedule 2759 * their delayed release). 2760 */ 2761 void ceph_put_fmode(struct ceph_inode_info *ci, int fmode) 2762 { 2763 struct inode *inode = &ci->vfs_inode; 2764 int last = 0; 2765 2766 spin_lock(&inode->i_lock); 2767 dout("put_fmode %p fmode %d %d -> %d\n", inode, fmode, 2768 ci->i_nr_by_mode[fmode], ci->i_nr_by_mode[fmode]-1); 2769 BUG_ON(ci->i_nr_by_mode[fmode] == 0); 2770 if (--ci->i_nr_by_mode[fmode] == 0) 2771 last++; 2772 spin_unlock(&inode->i_lock); 2773 2774 if (last && ci->i_vino.snap == CEPH_NOSNAP) 2775 ceph_check_caps(ci, 0, NULL); 2776 } 2777 2778 /* 2779 * Helpers for embedding cap and dentry lease releases into mds 2780 * requests. 2781 * 2782 * @force is used by dentry_release (below) to force inclusion of a 2783 * record for the directory inode, even when there aren't any caps to 2784 * drop. 2785 */ 2786 int ceph_encode_inode_release(void **p, struct inode *inode, 2787 int mds, int drop, int unless, int force) 2788 { 2789 struct ceph_inode_info *ci = ceph_inode(inode); 2790 struct ceph_cap *cap; 2791 struct ceph_mds_request_release *rel = *p; 2792 int ret = 0; 2793 2794 dout("encode_inode_release %p mds%d drop %s unless %s\n", inode, 2795 mds, ceph_cap_string(drop), ceph_cap_string(unless)); 2796 2797 spin_lock(&inode->i_lock); 2798 cap = __get_cap_for_mds(ci, mds); 2799 if (cap && __cap_is_valid(cap)) { 2800 if (force || 2801 ((cap->issued & drop) && 2802 (cap->issued & unless) == 0)) { 2803 if ((cap->issued & drop) && 2804 (cap->issued & unless) == 0) { 2805 dout("encode_inode_release %p cap %p %s -> " 2806 "%s\n", inode, cap, 2807 ceph_cap_string(cap->issued), 2808 ceph_cap_string(cap->issued & ~drop)); 2809 cap->issued &= ~drop; 2810 cap->implemented &= ~drop; 2811 if (ci->i_ceph_flags & CEPH_I_NODELAY) { 2812 int wanted = __ceph_caps_wanted(ci); 2813 dout(" wanted %s -> %s (act %s)\n", 2814 ceph_cap_string(cap->mds_wanted), 2815 ceph_cap_string(cap->mds_wanted & 2816 ~wanted), 2817 ceph_cap_string(wanted)); 2818 cap->mds_wanted &= wanted; 2819 } 2820 } else { 2821 dout("encode_inode_release %p cap %p %s" 2822 " (force)\n", inode, cap, 2823 ceph_cap_string(cap->issued)); 2824 } 2825 2826 rel->ino = cpu_to_le64(ceph_ino(inode)); 2827 rel->cap_id = cpu_to_le64(cap->cap_id); 2828 rel->seq = cpu_to_le32(cap->seq); 2829 rel->issue_seq = cpu_to_le32(cap->issue_seq), 2830 rel->mseq = cpu_to_le32(cap->mseq); 2831 rel->caps = cpu_to_le32(cap->issued); 2832 rel->wanted = cpu_to_le32(cap->mds_wanted); 2833 rel->dname_len = 0; 2834 rel->dname_seq = 0; 2835 *p += sizeof(*rel); 2836 ret = 1; 2837 } else { 2838 dout("encode_inode_release %p cap %p %s\n", 2839 inode, cap, ceph_cap_string(cap->issued)); 2840 } 2841 } 2842 spin_unlock(&inode->i_lock); 2843 return ret; 2844 } 2845 2846 int ceph_encode_dentry_release(void **p, struct dentry *dentry, 2847 int mds, int drop, int unless) 2848 { 2849 struct inode *dir = dentry->d_parent->d_inode; 2850 struct ceph_mds_request_release *rel = *p; 2851 struct ceph_dentry_info *di = ceph_dentry(dentry); 2852 int force = 0; 2853 int ret; 2854 2855 /* 2856 * force an record for the directory caps if we have a dentry lease. 2857 * this is racy (can't take i_lock and d_lock together), but it 2858 * doesn't have to be perfect; the mds will revoke anything we don't 2859 * release. 2860 */ 2861 spin_lock(&dentry->d_lock); 2862 if (di->lease_session && di->lease_session->s_mds == mds) 2863 force = 1; 2864 spin_unlock(&dentry->d_lock); 2865 2866 ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force); 2867 2868 spin_lock(&dentry->d_lock); 2869 if (ret && di->lease_session && di->lease_session->s_mds == mds) { 2870 dout("encode_dentry_release %p mds%d seq %d\n", 2871 dentry, mds, (int)di->lease_seq); 2872 rel->dname_len = cpu_to_le32(dentry->d_name.len); 2873 memcpy(*p, dentry->d_name.name, dentry->d_name.len); 2874 *p += dentry->d_name.len; 2875 rel->dname_seq = cpu_to_le32(di->lease_seq); 2876 } 2877 spin_unlock(&dentry->d_lock); 2878 return ret; 2879 } 2880