1 /* 2 * linux/fs/nfs/callback_proc.c 3 * 4 * Copyright (C) 2004 Trond Myklebust 5 * 6 * NFSv4 callback procedures 7 */ 8 #include <linux/nfs4.h> 9 #include <linux/nfs_fs.h> 10 #include <linux/slab.h> 11 #include <linux/rcupdate.h> 12 #include "nfs4_fs.h" 13 #include "callback.h" 14 #include "delegation.h" 15 #include "internal.h" 16 #include "pnfs.h" 17 #include "nfs4session.h" 18 #include "nfs4trace.h" 19 20 #define NFSDBG_FACILITY NFSDBG_CALLBACK 21 22 __be32 nfs4_callback_getattr(struct cb_getattrargs *args, 23 struct cb_getattrres *res, 24 struct cb_process_state *cps) 25 { 26 struct nfs_delegation *delegation; 27 struct nfs_inode *nfsi; 28 struct inode *inode; 29 30 res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION); 31 if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */ 32 goto out; 33 34 res->bitmap[0] = res->bitmap[1] = 0; 35 res->status = htonl(NFS4ERR_BADHANDLE); 36 37 dprintk_rcu("NFS: GETATTR callback request from %s\n", 38 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); 39 40 inode = nfs_delegation_find_inode(cps->clp, &args->fh); 41 if (inode == NULL) { 42 trace_nfs4_cb_getattr(cps->clp, &args->fh, NULL, 43 -ntohl(res->status)); 44 goto out; 45 } 46 nfsi = NFS_I(inode); 47 rcu_read_lock(); 48 delegation = rcu_dereference(nfsi->delegation); 49 if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0) 50 goto out_iput; 51 res->size = i_size_read(inode); 52 res->change_attr = delegation->change_attr; 53 if (nfsi->nrequests != 0) 54 res->change_attr++; 55 res->ctime = inode->i_ctime; 56 res->mtime = inode->i_mtime; 57 res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) & 58 args->bitmap[0]; 59 res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) & 60 args->bitmap[1]; 61 res->status = 0; 62 out_iput: 63 rcu_read_unlock(); 64 trace_nfs4_cb_getattr(cps->clp, &args->fh, inode, -ntohl(res->status)); 65 iput(inode); 66 out: 67 dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status)); 68 return res->status; 69 } 70 71 __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy, 72 struct cb_process_state *cps) 73 { 74 struct inode *inode; 75 __be32 res; 76 77 res = htonl(NFS4ERR_OP_NOT_IN_SESSION); 78 if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */ 79 goto out; 80 81 dprintk_rcu("NFS: RECALL callback request from %s\n", 82 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); 83 84 res = htonl(NFS4ERR_BADHANDLE); 85 inode = nfs_delegation_find_inode(cps->clp, &args->fh); 86 if (inode == NULL) { 87 trace_nfs4_cb_recall(cps->clp, &args->fh, NULL, 88 &args->stateid, -ntohl(res)); 89 goto out; 90 } 91 /* Set up a helper thread to actually return the delegation */ 92 switch (nfs_async_inode_return_delegation(inode, &args->stateid)) { 93 case 0: 94 res = 0; 95 break; 96 case -ENOENT: 97 res = htonl(NFS4ERR_BAD_STATEID); 98 break; 99 default: 100 res = htonl(NFS4ERR_RESOURCE); 101 } 102 trace_nfs4_cb_recall(cps->clp, &args->fh, inode, 103 &args->stateid, -ntohl(res)); 104 iput(inode); 105 out: 106 dprintk("%s: exit with status = %d\n", __func__, ntohl(res)); 107 return res; 108 } 109 110 #if defined(CONFIG_NFS_V4_1) 111 112 /* 113 * Lookup a layout inode by stateid 114 * 115 * Note: returns a refcount on the inode and superblock 116 */ 117 static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp, 118 const nfs4_stateid *stateid) 119 { 120 struct nfs_server *server; 121 struct inode *inode; 122 struct pnfs_layout_hdr *lo; 123 124 restart: 125 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { 126 list_for_each_entry(lo, &server->layouts, plh_layouts) { 127 if (stateid != NULL && 128 !nfs4_stateid_match_other(stateid, &lo->plh_stateid)) 129 continue; 130 inode = igrab(lo->plh_inode); 131 if (!inode) 132 continue; 133 if (!nfs_sb_active(inode->i_sb)) { 134 rcu_read_unlock(); 135 spin_unlock(&clp->cl_lock); 136 iput(inode); 137 spin_lock(&clp->cl_lock); 138 rcu_read_lock(); 139 goto restart; 140 } 141 return inode; 142 } 143 } 144 145 return NULL; 146 } 147 148 /* 149 * Lookup a layout inode by filehandle. 150 * 151 * Note: returns a refcount on the inode and superblock 152 * 153 */ 154 static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp, 155 const struct nfs_fh *fh) 156 { 157 struct nfs_server *server; 158 struct nfs_inode *nfsi; 159 struct inode *inode; 160 struct pnfs_layout_hdr *lo; 161 162 restart: 163 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { 164 list_for_each_entry(lo, &server->layouts, plh_layouts) { 165 nfsi = NFS_I(lo->plh_inode); 166 if (nfs_compare_fh(fh, &nfsi->fh)) 167 continue; 168 if (nfsi->layout != lo) 169 continue; 170 inode = igrab(lo->plh_inode); 171 if (!inode) 172 continue; 173 if (!nfs_sb_active(inode->i_sb)) { 174 rcu_read_unlock(); 175 spin_unlock(&clp->cl_lock); 176 iput(inode); 177 spin_lock(&clp->cl_lock); 178 rcu_read_lock(); 179 goto restart; 180 } 181 return inode; 182 } 183 } 184 185 return NULL; 186 } 187 188 static struct inode *nfs_layout_find_inode(struct nfs_client *clp, 189 const struct nfs_fh *fh, 190 const nfs4_stateid *stateid) 191 { 192 struct inode *inode; 193 194 spin_lock(&clp->cl_lock); 195 rcu_read_lock(); 196 inode = nfs_layout_find_inode_by_stateid(clp, stateid); 197 if (!inode) 198 inode = nfs_layout_find_inode_by_fh(clp, fh); 199 rcu_read_unlock(); 200 spin_unlock(&clp->cl_lock); 201 202 return inode; 203 } 204 205 /* 206 * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing) 207 */ 208 static u32 pnfs_check_callback_stateid(struct pnfs_layout_hdr *lo, 209 const nfs4_stateid *new) 210 { 211 u32 oldseq, newseq; 212 213 /* Is the stateid still not initialised? */ 214 if (!pnfs_layout_is_valid(lo)) 215 return NFS4ERR_DELAY; 216 217 /* Mismatched stateid? */ 218 if (!nfs4_stateid_match_other(&lo->plh_stateid, new)) 219 return NFS4ERR_BAD_STATEID; 220 221 newseq = be32_to_cpu(new->seqid); 222 /* Are we already in a layout recall situation? */ 223 if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) && 224 lo->plh_return_seq != 0) { 225 if (newseq < lo->plh_return_seq) 226 return NFS4ERR_OLD_STATEID; 227 if (newseq > lo->plh_return_seq) 228 return NFS4ERR_DELAY; 229 goto out; 230 } 231 232 /* Check that the stateid matches what we think it should be. */ 233 oldseq = be32_to_cpu(lo->plh_stateid.seqid); 234 if (newseq > oldseq + 1) 235 return NFS4ERR_DELAY; 236 /* Crazy server! */ 237 if (newseq <= oldseq) 238 return NFS4ERR_OLD_STATEID; 239 out: 240 return NFS_OK; 241 } 242 243 static u32 initiate_file_draining(struct nfs_client *clp, 244 struct cb_layoutrecallargs *args) 245 { 246 struct inode *ino; 247 struct pnfs_layout_hdr *lo; 248 u32 rv = NFS4ERR_NOMATCHING_LAYOUT; 249 LIST_HEAD(free_me_list); 250 251 ino = nfs_layout_find_inode(clp, &args->cbl_fh, &args->cbl_stateid); 252 if (!ino) 253 goto out; 254 255 pnfs_layoutcommit_inode(ino, false); 256 257 258 spin_lock(&ino->i_lock); 259 lo = NFS_I(ino)->layout; 260 if (!lo) { 261 spin_unlock(&ino->i_lock); 262 goto out; 263 } 264 pnfs_get_layout_hdr(lo); 265 rv = pnfs_check_callback_stateid(lo, &args->cbl_stateid); 266 if (rv != NFS_OK) 267 goto unlock; 268 pnfs_set_layout_stateid(lo, &args->cbl_stateid, true); 269 270 /* 271 * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return) 272 */ 273 if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) { 274 rv = NFS4ERR_DELAY; 275 goto unlock; 276 } 277 278 if (pnfs_mark_matching_lsegs_return(lo, &free_me_list, 279 &args->cbl_range, 280 be32_to_cpu(args->cbl_stateid.seqid))) { 281 rv = NFS4_OK; 282 goto unlock; 283 } 284 285 /* Embrace your forgetfulness! */ 286 rv = NFS4ERR_NOMATCHING_LAYOUT; 287 288 if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) { 289 NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, 290 &args->cbl_range); 291 } 292 unlock: 293 spin_unlock(&ino->i_lock); 294 pnfs_free_lseg_list(&free_me_list); 295 /* Free all lsegs that are attached to commit buckets */ 296 nfs_commit_inode(ino, 0); 297 pnfs_put_layout_hdr(lo); 298 out: 299 trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino, 300 &args->cbl_stateid, -rv); 301 nfs_iput_and_deactive(ino); 302 return rv; 303 } 304 305 static u32 initiate_bulk_draining(struct nfs_client *clp, 306 struct cb_layoutrecallargs *args) 307 { 308 int stat; 309 310 if (args->cbl_recall_type == RETURN_FSID) 311 stat = pnfs_destroy_layouts_byfsid(clp, &args->cbl_fsid, true); 312 else 313 stat = pnfs_destroy_layouts_byclid(clp, true); 314 if (stat != 0) 315 return NFS4ERR_DELAY; 316 return NFS4ERR_NOMATCHING_LAYOUT; 317 } 318 319 static u32 do_callback_layoutrecall(struct nfs_client *clp, 320 struct cb_layoutrecallargs *args) 321 { 322 if (args->cbl_recall_type == RETURN_FILE) 323 return initiate_file_draining(clp, args); 324 return initiate_bulk_draining(clp, args); 325 } 326 327 __be32 nfs4_callback_layoutrecall(struct cb_layoutrecallargs *args, 328 void *dummy, struct cb_process_state *cps) 329 { 330 u32 res = NFS4ERR_OP_NOT_IN_SESSION; 331 332 if (cps->clp) 333 res = do_callback_layoutrecall(cps->clp, args); 334 return cpu_to_be32(res); 335 } 336 337 static void pnfs_recall_all_layouts(struct nfs_client *clp) 338 { 339 struct cb_layoutrecallargs args; 340 341 /* Pretend we got a CB_LAYOUTRECALL(ALL) */ 342 memset(&args, 0, sizeof(args)); 343 args.cbl_recall_type = RETURN_ALL; 344 /* FIXME we ignore errors, what should we do? */ 345 do_callback_layoutrecall(clp, &args); 346 } 347 348 __be32 nfs4_callback_devicenotify(struct cb_devicenotifyargs *args, 349 void *dummy, struct cb_process_state *cps) 350 { 351 int i; 352 __be32 res = 0; 353 struct nfs_client *clp = cps->clp; 354 struct nfs_server *server = NULL; 355 356 if (!clp) { 357 res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION); 358 goto out; 359 } 360 361 for (i = 0; i < args->ndevs; i++) { 362 struct cb_devicenotifyitem *dev = &args->devs[i]; 363 364 if (!server || 365 server->pnfs_curr_ld->id != dev->cbd_layout_type) { 366 rcu_read_lock(); 367 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) 368 if (server->pnfs_curr_ld && 369 server->pnfs_curr_ld->id == dev->cbd_layout_type) { 370 rcu_read_unlock(); 371 goto found; 372 } 373 rcu_read_unlock(); 374 continue; 375 } 376 377 found: 378 nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id); 379 } 380 381 out: 382 kfree(args->devs); 383 return res; 384 } 385 386 /* 387 * Validate the sequenceID sent by the server. 388 * Return success if the sequenceID is one more than what we last saw on 389 * this slot, accounting for wraparound. Increments the slot's sequence. 390 * 391 * We don't yet implement a duplicate request cache, instead we set the 392 * back channel ca_maxresponsesize_cached to zero. This is OK for now 393 * since we only currently implement idempotent callbacks anyway. 394 * 395 * We have a single slot backchannel at this time, so we don't bother 396 * checking the used_slots bit array on the table. The lower layer guarantees 397 * a single outstanding callback request at a time. 398 */ 399 static __be32 400 validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot, 401 const struct cb_sequenceargs * args) 402 { 403 if (args->csa_slotid > tbl->server_highest_slotid) 404 return htonl(NFS4ERR_BADSLOT); 405 406 /* Replay */ 407 if (args->csa_sequenceid == slot->seq_nr) { 408 if (nfs4_test_locked_slot(tbl, slot->slot_nr)) 409 return htonl(NFS4ERR_DELAY); 410 /* Signal process_op to set this error on next op */ 411 if (args->csa_cachethis == 0) 412 return htonl(NFS4ERR_RETRY_UNCACHED_REP); 413 414 /* Liar! We never allowed you to set csa_cachethis != 0 */ 415 return htonl(NFS4ERR_SEQ_FALSE_RETRY); 416 } 417 418 /* Wraparound */ 419 if (unlikely(slot->seq_nr == 0xFFFFFFFFU)) { 420 if (args->csa_sequenceid == 1) 421 return htonl(NFS4_OK); 422 } else if (likely(args->csa_sequenceid == slot->seq_nr + 1)) 423 return htonl(NFS4_OK); 424 425 /* Misordered request */ 426 return htonl(NFS4ERR_SEQ_MISORDERED); 427 } 428 429 /* 430 * For each referring call triple, check the session's slot table for 431 * a match. If the slot is in use and the sequence numbers match, the 432 * client is still waiting for a response to the original request. 433 */ 434 static bool referring_call_exists(struct nfs_client *clp, 435 uint32_t nrclists, 436 struct referring_call_list *rclists) 437 { 438 bool status = 0; 439 int i, j; 440 struct nfs4_session *session; 441 struct nfs4_slot_table *tbl; 442 struct referring_call_list *rclist; 443 struct referring_call *ref; 444 445 /* 446 * XXX When client trunking is implemented, this becomes 447 * a session lookup from within the loop 448 */ 449 session = clp->cl_session; 450 tbl = &session->fc_slot_table; 451 452 for (i = 0; i < nrclists; i++) { 453 rclist = &rclists[i]; 454 if (memcmp(session->sess_id.data, 455 rclist->rcl_sessionid.data, 456 NFS4_MAX_SESSIONID_LEN) != 0) 457 continue; 458 459 for (j = 0; j < rclist->rcl_nrefcalls; j++) { 460 ref = &rclist->rcl_refcalls[j]; 461 status = nfs4_slot_wait_on_seqid(tbl, ref->rc_slotid, 462 ref->rc_sequenceid, HZ >> 1) < 0; 463 if (status) 464 goto out; 465 } 466 } 467 468 out: 469 return status; 470 } 471 472 __be32 nfs4_callback_sequence(struct cb_sequenceargs *args, 473 struct cb_sequenceres *res, 474 struct cb_process_state *cps) 475 { 476 struct nfs4_slot_table *tbl; 477 struct nfs4_slot *slot; 478 struct nfs_client *clp; 479 int i; 480 __be32 status = htonl(NFS4ERR_BADSESSION); 481 482 clp = nfs4_find_client_sessionid(cps->net, args->csa_addr, 483 &args->csa_sessionid, cps->minorversion); 484 if (clp == NULL) 485 goto out; 486 487 if (!(clp->cl_session->flags & SESSION4_BACK_CHAN)) 488 goto out; 489 490 tbl = &clp->cl_session->bc_slot_table; 491 492 /* Set up res before grabbing the spinlock */ 493 memcpy(&res->csr_sessionid, &args->csa_sessionid, 494 sizeof(res->csr_sessionid)); 495 res->csr_sequenceid = args->csa_sequenceid; 496 res->csr_slotid = args->csa_slotid; 497 498 spin_lock(&tbl->slot_tbl_lock); 499 /* state manager is resetting the session */ 500 if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) { 501 status = htonl(NFS4ERR_DELAY); 502 /* Return NFS4ERR_BADSESSION if we're draining the session 503 * in order to reset it. 504 */ 505 if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) 506 status = htonl(NFS4ERR_BADSESSION); 507 goto out_unlock; 508 } 509 510 status = htonl(NFS4ERR_BADSLOT); 511 slot = nfs4_lookup_slot(tbl, args->csa_slotid); 512 if (IS_ERR(slot)) 513 goto out_unlock; 514 515 res->csr_highestslotid = tbl->server_highest_slotid; 516 res->csr_target_highestslotid = tbl->target_highest_slotid; 517 518 status = validate_seqid(tbl, slot, args); 519 if (status) 520 goto out_unlock; 521 if (!nfs4_try_to_lock_slot(tbl, slot)) { 522 status = htonl(NFS4ERR_DELAY); 523 goto out_unlock; 524 } 525 cps->slot = slot; 526 527 /* The ca_maxresponsesize_cached is 0 with no DRC */ 528 if (args->csa_cachethis != 0) { 529 status = htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE); 530 goto out_unlock; 531 } 532 533 /* 534 * Check for pending referring calls. If a match is found, a 535 * related callback was received before the response to the original 536 * call. 537 */ 538 if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) { 539 status = htonl(NFS4ERR_DELAY); 540 goto out_unlock; 541 } 542 543 /* 544 * RFC5661 20.9.3 545 * If CB_SEQUENCE returns an error, then the state of the slot 546 * (sequence ID, cached reply) MUST NOT change. 547 */ 548 slot->seq_nr = args->csa_sequenceid; 549 out_unlock: 550 spin_unlock(&tbl->slot_tbl_lock); 551 552 out: 553 cps->clp = clp; /* put in nfs4_callback_compound */ 554 for (i = 0; i < args->csa_nrclists; i++) 555 kfree(args->csa_rclists[i].rcl_refcalls); 556 kfree(args->csa_rclists); 557 558 if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) { 559 cps->drc_status = status; 560 status = 0; 561 } else 562 res->csr_status = status; 563 564 trace_nfs4_cb_sequence(args, res, status); 565 return status; 566 } 567 568 static bool 569 validate_bitmap_values(unsigned long mask) 570 { 571 return (mask & ~RCA4_TYPE_MASK_ALL) == 0; 572 } 573 574 __be32 nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy, 575 struct cb_process_state *cps) 576 { 577 __be32 status; 578 fmode_t flags = 0; 579 580 status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION); 581 if (!cps->clp) /* set in cb_sequence */ 582 goto out; 583 584 dprintk_rcu("NFS: RECALL_ANY callback request from %s\n", 585 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); 586 587 status = cpu_to_be32(NFS4ERR_INVAL); 588 if (!validate_bitmap_values(args->craa_type_mask)) 589 goto out; 590 591 status = cpu_to_be32(NFS4_OK); 592 if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *) 593 &args->craa_type_mask)) 594 flags = FMODE_READ; 595 if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *) 596 &args->craa_type_mask)) 597 flags |= FMODE_WRITE; 598 if (test_bit(RCA4_TYPE_MASK_FILE_LAYOUT, (const unsigned long *) 599 &args->craa_type_mask)) 600 pnfs_recall_all_layouts(cps->clp); 601 if (flags) 602 nfs_expire_unused_delegation_types(cps->clp, flags); 603 out: 604 dprintk("%s: exit with status = %d\n", __func__, ntohl(status)); 605 return status; 606 } 607 608 /* Reduce the fore channel's max_slots to the target value */ 609 __be32 nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy, 610 struct cb_process_state *cps) 611 { 612 struct nfs4_slot_table *fc_tbl; 613 __be32 status; 614 615 status = htonl(NFS4ERR_OP_NOT_IN_SESSION); 616 if (!cps->clp) /* set in cb_sequence */ 617 goto out; 618 619 dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n", 620 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR), 621 args->crsa_target_highest_slotid); 622 623 fc_tbl = &cps->clp->cl_session->fc_slot_table; 624 625 status = htonl(NFS4_OK); 626 627 nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid); 628 nfs41_notify_server(cps->clp); 629 out: 630 dprintk("%s: exit with status = %d\n", __func__, ntohl(status)); 631 return status; 632 } 633 634 __be32 nfs4_callback_notify_lock(struct cb_notify_lock_args *args, void *dummy, 635 struct cb_process_state *cps) 636 { 637 if (!cps->clp) /* set in cb_sequence */ 638 return htonl(NFS4ERR_OP_NOT_IN_SESSION); 639 640 dprintk_rcu("NFS: CB_NOTIFY_LOCK request from %s\n", 641 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); 642 643 /* Don't wake anybody if the string looked bogus */ 644 if (args->cbnl_valid) 645 __wake_up(&cps->clp->cl_lock_waitq, TASK_NORMAL, 0, args); 646 647 return htonl(NFS4_OK); 648 } 649 #endif /* CONFIG_NFS_V4_1 */ 650