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(void *argp, void *resp, 23 struct cb_process_state *cps) 24 { 25 struct cb_getattrargs *args = argp; 26 struct cb_getattrres *res = resp; 27 struct nfs_delegation *delegation; 28 struct nfs_inode *nfsi; 29 struct inode *inode; 30 31 res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION); 32 if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */ 33 goto out; 34 35 res->bitmap[0] = res->bitmap[1] = 0; 36 res->status = htonl(NFS4ERR_BADHANDLE); 37 38 dprintk_rcu("NFS: GETATTR callback request from %s\n", 39 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); 40 41 inode = nfs_delegation_find_inode(cps->clp, &args->fh); 42 if (inode == NULL) { 43 trace_nfs4_cb_getattr(cps->clp, &args->fh, NULL, 44 -ntohl(res->status)); 45 goto out; 46 } 47 nfsi = NFS_I(inode); 48 rcu_read_lock(); 49 delegation = rcu_dereference(nfsi->delegation); 50 if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0) 51 goto out_iput; 52 res->size = i_size_read(inode); 53 res->change_attr = delegation->change_attr; 54 if (nfs_have_writebacks(inode)) 55 res->change_attr++; 56 res->ctime = inode->i_ctime; 57 res->mtime = inode->i_mtime; 58 res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) & 59 args->bitmap[0]; 60 res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) & 61 args->bitmap[1]; 62 res->status = 0; 63 out_iput: 64 rcu_read_unlock(); 65 trace_nfs4_cb_getattr(cps->clp, &args->fh, inode, -ntohl(res->status)); 66 iput(inode); 67 out: 68 dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status)); 69 return res->status; 70 } 71 72 __be32 nfs4_callback_recall(void *argp, void *resp, 73 struct cb_process_state *cps) 74 { 75 struct cb_recallargs *args = argp; 76 struct inode *inode; 77 __be32 res; 78 79 res = htonl(NFS4ERR_OP_NOT_IN_SESSION); 80 if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */ 81 goto out; 82 83 dprintk_rcu("NFS: RECALL callback request from %s\n", 84 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); 85 86 res = htonl(NFS4ERR_BADHANDLE); 87 inode = nfs_delegation_find_inode(cps->clp, &args->fh); 88 if (inode == NULL) { 89 trace_nfs4_cb_recall(cps->clp, &args->fh, NULL, 90 &args->stateid, -ntohl(res)); 91 goto out; 92 } 93 /* Set up a helper thread to actually return the delegation */ 94 switch (nfs_async_inode_return_delegation(inode, &args->stateid)) { 95 case 0: 96 res = 0; 97 break; 98 case -ENOENT: 99 res = htonl(NFS4ERR_BAD_STATEID); 100 break; 101 default: 102 res = htonl(NFS4ERR_RESOURCE); 103 } 104 trace_nfs4_cb_recall(cps->clp, &args->fh, inode, 105 &args->stateid, -ntohl(res)); 106 iput(inode); 107 out: 108 dprintk("%s: exit with status = %d\n", __func__, ntohl(res)); 109 return res; 110 } 111 112 #if defined(CONFIG_NFS_V4_1) 113 114 /* 115 * Lookup a layout inode by stateid 116 * 117 * Note: returns a refcount on the inode and superblock 118 */ 119 static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp, 120 const nfs4_stateid *stateid) 121 { 122 struct nfs_server *server; 123 struct inode *inode; 124 struct pnfs_layout_hdr *lo; 125 126 restart: 127 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { 128 list_for_each_entry(lo, &server->layouts, plh_layouts) { 129 if (stateid != NULL && 130 !nfs4_stateid_match_other(stateid, &lo->plh_stateid)) 131 continue; 132 inode = igrab(lo->plh_inode); 133 if (!inode) 134 continue; 135 if (!nfs_sb_active(inode->i_sb)) { 136 rcu_read_unlock(); 137 spin_unlock(&clp->cl_lock); 138 iput(inode); 139 spin_lock(&clp->cl_lock); 140 rcu_read_lock(); 141 goto restart; 142 } 143 return inode; 144 } 145 } 146 147 return NULL; 148 } 149 150 /* 151 * Lookup a layout inode by filehandle. 152 * 153 * Note: returns a refcount on the inode and superblock 154 * 155 */ 156 static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp, 157 const struct nfs_fh *fh) 158 { 159 struct nfs_server *server; 160 struct nfs_inode *nfsi; 161 struct inode *inode; 162 struct pnfs_layout_hdr *lo; 163 164 restart: 165 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { 166 list_for_each_entry(lo, &server->layouts, plh_layouts) { 167 nfsi = NFS_I(lo->plh_inode); 168 if (nfs_compare_fh(fh, &nfsi->fh)) 169 continue; 170 if (nfsi->layout != lo) 171 continue; 172 inode = igrab(lo->plh_inode); 173 if (!inode) 174 continue; 175 if (!nfs_sb_active(inode->i_sb)) { 176 rcu_read_unlock(); 177 spin_unlock(&clp->cl_lock); 178 iput(inode); 179 spin_lock(&clp->cl_lock); 180 rcu_read_lock(); 181 goto restart; 182 } 183 return inode; 184 } 185 } 186 187 return NULL; 188 } 189 190 static struct inode *nfs_layout_find_inode(struct nfs_client *clp, 191 const struct nfs_fh *fh, 192 const nfs4_stateid *stateid) 193 { 194 struct inode *inode; 195 196 spin_lock(&clp->cl_lock); 197 rcu_read_lock(); 198 inode = nfs_layout_find_inode_by_stateid(clp, stateid); 199 if (!inode) 200 inode = nfs_layout_find_inode_by_fh(clp, fh); 201 rcu_read_unlock(); 202 spin_unlock(&clp->cl_lock); 203 204 return inode; 205 } 206 207 /* 208 * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing) 209 */ 210 static u32 pnfs_check_callback_stateid(struct pnfs_layout_hdr *lo, 211 const nfs4_stateid *new) 212 { 213 u32 oldseq, newseq; 214 215 /* Is the stateid still not initialised? */ 216 if (!pnfs_layout_is_valid(lo)) 217 return NFS4ERR_DELAY; 218 219 /* Mismatched stateid? */ 220 if (!nfs4_stateid_match_other(&lo->plh_stateid, new)) 221 return NFS4ERR_BAD_STATEID; 222 223 newseq = be32_to_cpu(new->seqid); 224 /* Are we already in a layout recall situation? */ 225 if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) && 226 lo->plh_return_seq != 0) { 227 if (newseq < lo->plh_return_seq) 228 return NFS4ERR_OLD_STATEID; 229 if (newseq > lo->plh_return_seq) 230 return NFS4ERR_DELAY; 231 goto out; 232 } 233 234 /* Check that the stateid matches what we think it should be. */ 235 oldseq = be32_to_cpu(lo->plh_stateid.seqid); 236 if (newseq > oldseq + 1) 237 return NFS4ERR_DELAY; 238 /* Crazy server! */ 239 if (newseq <= oldseq) 240 return NFS4ERR_OLD_STATEID; 241 out: 242 return NFS_OK; 243 } 244 245 static u32 initiate_file_draining(struct nfs_client *clp, 246 struct cb_layoutrecallargs *args) 247 { 248 struct inode *ino; 249 struct pnfs_layout_hdr *lo; 250 u32 rv = NFS4ERR_NOMATCHING_LAYOUT; 251 LIST_HEAD(free_me_list); 252 253 ino = nfs_layout_find_inode(clp, &args->cbl_fh, &args->cbl_stateid); 254 if (!ino) 255 goto out; 256 257 pnfs_layoutcommit_inode(ino, false); 258 259 260 spin_lock(&ino->i_lock); 261 lo = NFS_I(ino)->layout; 262 if (!lo) { 263 spin_unlock(&ino->i_lock); 264 goto out; 265 } 266 pnfs_get_layout_hdr(lo); 267 rv = pnfs_check_callback_stateid(lo, &args->cbl_stateid); 268 if (rv != NFS_OK) 269 goto unlock; 270 pnfs_set_layout_stateid(lo, &args->cbl_stateid, true); 271 272 /* 273 * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return) 274 */ 275 if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) { 276 rv = NFS4ERR_DELAY; 277 goto unlock; 278 } 279 280 if (pnfs_mark_matching_lsegs_return(lo, &free_me_list, 281 &args->cbl_range, 282 be32_to_cpu(args->cbl_stateid.seqid))) { 283 rv = NFS4_OK; 284 goto unlock; 285 } 286 287 /* Embrace your forgetfulness! */ 288 rv = NFS4ERR_NOMATCHING_LAYOUT; 289 290 if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) { 291 NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, 292 &args->cbl_range); 293 } 294 unlock: 295 spin_unlock(&ino->i_lock); 296 pnfs_free_lseg_list(&free_me_list); 297 /* Free all lsegs that are attached to commit buckets */ 298 nfs_commit_inode(ino, 0); 299 pnfs_put_layout_hdr(lo); 300 out: 301 trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino, 302 &args->cbl_stateid, -rv); 303 nfs_iput_and_deactive(ino); 304 return rv; 305 } 306 307 static u32 initiate_bulk_draining(struct nfs_client *clp, 308 struct cb_layoutrecallargs *args) 309 { 310 int stat; 311 312 if (args->cbl_recall_type == RETURN_FSID) 313 stat = pnfs_destroy_layouts_byfsid(clp, &args->cbl_fsid, true); 314 else 315 stat = pnfs_destroy_layouts_byclid(clp, true); 316 if (stat != 0) 317 return NFS4ERR_DELAY; 318 return NFS4ERR_NOMATCHING_LAYOUT; 319 } 320 321 static u32 do_callback_layoutrecall(struct nfs_client *clp, 322 struct cb_layoutrecallargs *args) 323 { 324 if (args->cbl_recall_type == RETURN_FILE) 325 return initiate_file_draining(clp, args); 326 return initiate_bulk_draining(clp, args); 327 } 328 329 __be32 nfs4_callback_layoutrecall(void *argp, void *resp, 330 struct cb_process_state *cps) 331 { 332 struct cb_layoutrecallargs *args = argp; 333 u32 res = NFS4ERR_OP_NOT_IN_SESSION; 334 335 if (cps->clp) 336 res = do_callback_layoutrecall(cps->clp, args); 337 return cpu_to_be32(res); 338 } 339 340 static void pnfs_recall_all_layouts(struct nfs_client *clp) 341 { 342 struct cb_layoutrecallargs args; 343 344 /* Pretend we got a CB_LAYOUTRECALL(ALL) */ 345 memset(&args, 0, sizeof(args)); 346 args.cbl_recall_type = RETURN_ALL; 347 /* FIXME we ignore errors, what should we do? */ 348 do_callback_layoutrecall(clp, &args); 349 } 350 351 __be32 nfs4_callback_devicenotify(void *argp, void *resp, 352 struct cb_process_state *cps) 353 { 354 struct cb_devicenotifyargs *args = argp; 355 int i; 356 __be32 res = 0; 357 struct nfs_client *clp = cps->clp; 358 struct nfs_server *server = NULL; 359 360 if (!clp) { 361 res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION); 362 goto out; 363 } 364 365 for (i = 0; i < args->ndevs; i++) { 366 struct cb_devicenotifyitem *dev = &args->devs[i]; 367 368 if (!server || 369 server->pnfs_curr_ld->id != dev->cbd_layout_type) { 370 rcu_read_lock(); 371 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) 372 if (server->pnfs_curr_ld && 373 server->pnfs_curr_ld->id == dev->cbd_layout_type) { 374 rcu_read_unlock(); 375 goto found; 376 } 377 rcu_read_unlock(); 378 continue; 379 } 380 381 found: 382 nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id); 383 } 384 385 out: 386 kfree(args->devs); 387 return res; 388 } 389 390 /* 391 * Validate the sequenceID sent by the server. 392 * Return success if the sequenceID is one more than what we last saw on 393 * this slot, accounting for wraparound. Increments the slot's sequence. 394 * 395 * We don't yet implement a duplicate request cache, instead we set the 396 * back channel ca_maxresponsesize_cached to zero. This is OK for now 397 * since we only currently implement idempotent callbacks anyway. 398 * 399 * We have a single slot backchannel at this time, so we don't bother 400 * checking the used_slots bit array on the table. The lower layer guarantees 401 * a single outstanding callback request at a time. 402 */ 403 static __be32 404 validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot, 405 const struct cb_sequenceargs * args) 406 { 407 if (args->csa_slotid > tbl->server_highest_slotid) 408 return htonl(NFS4ERR_BADSLOT); 409 410 /* Replay */ 411 if (args->csa_sequenceid == slot->seq_nr) { 412 if (nfs4_test_locked_slot(tbl, slot->slot_nr)) 413 return htonl(NFS4ERR_DELAY); 414 /* Signal process_op to set this error on next op */ 415 if (args->csa_cachethis == 0) 416 return htonl(NFS4ERR_RETRY_UNCACHED_REP); 417 418 /* Liar! We never allowed you to set csa_cachethis != 0 */ 419 return htonl(NFS4ERR_SEQ_FALSE_RETRY); 420 } 421 422 /* Wraparound */ 423 if (unlikely(slot->seq_nr == 0xFFFFFFFFU)) { 424 if (args->csa_sequenceid == 1) 425 return htonl(NFS4_OK); 426 } else if (likely(args->csa_sequenceid == slot->seq_nr + 1)) 427 return htonl(NFS4_OK); 428 429 /* Misordered request */ 430 return htonl(NFS4ERR_SEQ_MISORDERED); 431 } 432 433 /* 434 * For each referring call triple, check the session's slot table for 435 * a match. If the slot is in use and the sequence numbers match, the 436 * client is still waiting for a response to the original request. 437 */ 438 static bool referring_call_exists(struct nfs_client *clp, 439 uint32_t nrclists, 440 struct referring_call_list *rclists) 441 { 442 bool status = 0; 443 int i, j; 444 struct nfs4_session *session; 445 struct nfs4_slot_table *tbl; 446 struct referring_call_list *rclist; 447 struct referring_call *ref; 448 449 /* 450 * XXX When client trunking is implemented, this becomes 451 * a session lookup from within the loop 452 */ 453 session = clp->cl_session; 454 tbl = &session->fc_slot_table; 455 456 for (i = 0; i < nrclists; i++) { 457 rclist = &rclists[i]; 458 if (memcmp(session->sess_id.data, 459 rclist->rcl_sessionid.data, 460 NFS4_MAX_SESSIONID_LEN) != 0) 461 continue; 462 463 for (j = 0; j < rclist->rcl_nrefcalls; j++) { 464 ref = &rclist->rcl_refcalls[j]; 465 status = nfs4_slot_wait_on_seqid(tbl, ref->rc_slotid, 466 ref->rc_sequenceid, HZ >> 1) < 0; 467 if (status) 468 goto out; 469 } 470 } 471 472 out: 473 return status; 474 } 475 476 __be32 nfs4_callback_sequence(void *argp, void *resp, 477 struct cb_process_state *cps) 478 { 479 struct cb_sequenceargs *args = argp; 480 struct cb_sequenceres *res = resp; 481 struct nfs4_slot_table *tbl; 482 struct nfs4_slot *slot; 483 struct nfs_client *clp; 484 int i; 485 __be32 status = htonl(NFS4ERR_BADSESSION); 486 487 clp = nfs4_find_client_sessionid(cps->net, args->csa_addr, 488 &args->csa_sessionid, cps->minorversion); 489 if (clp == NULL) 490 goto out; 491 492 if (!(clp->cl_session->flags & SESSION4_BACK_CHAN)) 493 goto out; 494 495 tbl = &clp->cl_session->bc_slot_table; 496 497 /* Set up res before grabbing the spinlock */ 498 memcpy(&res->csr_sessionid, &args->csa_sessionid, 499 sizeof(res->csr_sessionid)); 500 res->csr_sequenceid = args->csa_sequenceid; 501 res->csr_slotid = args->csa_slotid; 502 503 spin_lock(&tbl->slot_tbl_lock); 504 /* state manager is resetting the session */ 505 if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) { 506 status = htonl(NFS4ERR_DELAY); 507 /* Return NFS4ERR_BADSESSION if we're draining the session 508 * in order to reset it. 509 */ 510 if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) 511 status = htonl(NFS4ERR_BADSESSION); 512 goto out_unlock; 513 } 514 515 status = htonl(NFS4ERR_BADSLOT); 516 slot = nfs4_lookup_slot(tbl, args->csa_slotid); 517 if (IS_ERR(slot)) 518 goto out_unlock; 519 520 res->csr_highestslotid = tbl->server_highest_slotid; 521 res->csr_target_highestslotid = tbl->target_highest_slotid; 522 523 status = validate_seqid(tbl, slot, args); 524 if (status) 525 goto out_unlock; 526 if (!nfs4_try_to_lock_slot(tbl, slot)) { 527 status = htonl(NFS4ERR_DELAY); 528 goto out_unlock; 529 } 530 cps->slot = slot; 531 532 /* The ca_maxresponsesize_cached is 0 with no DRC */ 533 if (args->csa_cachethis != 0) { 534 status = htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE); 535 goto out_unlock; 536 } 537 538 /* 539 * Check for pending referring calls. If a match is found, a 540 * related callback was received before the response to the original 541 * call. 542 */ 543 if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) { 544 status = htonl(NFS4ERR_DELAY); 545 goto out_unlock; 546 } 547 548 /* 549 * RFC5661 20.9.3 550 * If CB_SEQUENCE returns an error, then the state of the slot 551 * (sequence ID, cached reply) MUST NOT change. 552 */ 553 slot->seq_nr = args->csa_sequenceid; 554 out_unlock: 555 spin_unlock(&tbl->slot_tbl_lock); 556 557 out: 558 cps->clp = clp; /* put in nfs4_callback_compound */ 559 for (i = 0; i < args->csa_nrclists; i++) 560 kfree(args->csa_rclists[i].rcl_refcalls); 561 kfree(args->csa_rclists); 562 563 if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) { 564 cps->drc_status = status; 565 status = 0; 566 } else 567 res->csr_status = status; 568 569 trace_nfs4_cb_sequence(args, res, status); 570 return status; 571 } 572 573 static bool 574 validate_bitmap_values(unsigned long mask) 575 { 576 return (mask & ~RCA4_TYPE_MASK_ALL) == 0; 577 } 578 579 __be32 nfs4_callback_recallany(void *argp, void *resp, 580 struct cb_process_state *cps) 581 { 582 struct cb_recallanyargs *args = argp; 583 __be32 status; 584 fmode_t flags = 0; 585 586 status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION); 587 if (!cps->clp) /* set in cb_sequence */ 588 goto out; 589 590 dprintk_rcu("NFS: RECALL_ANY callback request from %s\n", 591 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); 592 593 status = cpu_to_be32(NFS4ERR_INVAL); 594 if (!validate_bitmap_values(args->craa_type_mask)) 595 goto out; 596 597 status = cpu_to_be32(NFS4_OK); 598 if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *) 599 &args->craa_type_mask)) 600 flags = FMODE_READ; 601 if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *) 602 &args->craa_type_mask)) 603 flags |= FMODE_WRITE; 604 if (test_bit(RCA4_TYPE_MASK_FILE_LAYOUT, (const unsigned long *) 605 &args->craa_type_mask)) 606 pnfs_recall_all_layouts(cps->clp); 607 if (flags) 608 nfs_expire_unused_delegation_types(cps->clp, flags); 609 out: 610 dprintk("%s: exit with status = %d\n", __func__, ntohl(status)); 611 return status; 612 } 613 614 /* Reduce the fore channel's max_slots to the target value */ 615 __be32 nfs4_callback_recallslot(void *argp, void *resp, 616 struct cb_process_state *cps) 617 { 618 struct cb_recallslotargs *args = argp; 619 struct nfs4_slot_table *fc_tbl; 620 __be32 status; 621 622 status = htonl(NFS4ERR_OP_NOT_IN_SESSION); 623 if (!cps->clp) /* set in cb_sequence */ 624 goto out; 625 626 dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n", 627 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR), 628 args->crsa_target_highest_slotid); 629 630 fc_tbl = &cps->clp->cl_session->fc_slot_table; 631 632 status = htonl(NFS4_OK); 633 634 nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid); 635 nfs41_notify_server(cps->clp); 636 out: 637 dprintk("%s: exit with status = %d\n", __func__, ntohl(status)); 638 return status; 639 } 640 641 __be32 nfs4_callback_notify_lock(void *argp, void *resp, 642 struct cb_process_state *cps) 643 { 644 struct cb_notify_lock_args *args = argp; 645 646 if (!cps->clp) /* set in cb_sequence */ 647 return htonl(NFS4ERR_OP_NOT_IN_SESSION); 648 649 dprintk_rcu("NFS: CB_NOTIFY_LOCK request from %s\n", 650 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); 651 652 /* Don't wake anybody if the string looked bogus */ 653 if (args->cbnl_valid) 654 __wake_up(&cps->clp->cl_lock_waitq, TASK_NORMAL, 0, args); 655 656 return htonl(NFS4_OK); 657 } 658 #endif /* CONFIG_NFS_V4_1 */ 659