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 by filehandle. 114 * 115 * Note: gets a refcount on the layout hdr and on its respective inode. 116 * Caller must put the layout hdr and the inode. 117 * 118 * TODO: keep track of all layouts (and delegations) in a hash table 119 * hashed by filehandle. 120 */ 121 static struct pnfs_layout_hdr * get_layout_by_fh_locked(struct nfs_client *clp, 122 struct nfs_fh *fh, nfs4_stateid *stateid) 123 { 124 struct nfs_server *server; 125 struct inode *ino; 126 struct pnfs_layout_hdr *lo; 127 128 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { 129 list_for_each_entry(lo, &server->layouts, plh_layouts) { 130 if (!nfs4_stateid_match_other(&lo->plh_stateid, stateid)) 131 continue; 132 if (nfs_compare_fh(fh, &NFS_I(lo->plh_inode)->fh)) 133 continue; 134 ino = igrab(lo->plh_inode); 135 if (!ino) 136 break; 137 spin_lock(&ino->i_lock); 138 /* Is this layout in the process of being freed? */ 139 if (NFS_I(ino)->layout != lo) { 140 spin_unlock(&ino->i_lock); 141 iput(ino); 142 break; 143 } 144 pnfs_get_layout_hdr(lo); 145 spin_unlock(&ino->i_lock); 146 return lo; 147 } 148 } 149 150 return NULL; 151 } 152 153 static struct pnfs_layout_hdr * get_layout_by_fh(struct nfs_client *clp, 154 struct nfs_fh *fh, nfs4_stateid *stateid) 155 { 156 struct pnfs_layout_hdr *lo; 157 158 spin_lock(&clp->cl_lock); 159 rcu_read_lock(); 160 lo = get_layout_by_fh_locked(clp, fh, stateid); 161 rcu_read_unlock(); 162 spin_unlock(&clp->cl_lock); 163 164 return lo; 165 } 166 167 /* 168 * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing) 169 */ 170 static bool pnfs_check_stateid_sequence(struct pnfs_layout_hdr *lo, 171 const nfs4_stateid *new) 172 { 173 u32 oldseq, newseq; 174 175 oldseq = be32_to_cpu(lo->plh_stateid.seqid); 176 newseq = be32_to_cpu(new->seqid); 177 178 if (newseq > oldseq + 1) 179 return false; 180 return true; 181 } 182 183 static u32 initiate_file_draining(struct nfs_client *clp, 184 struct cb_layoutrecallargs *args) 185 { 186 struct inode *ino; 187 struct pnfs_layout_hdr *lo; 188 u32 rv = NFS4ERR_NOMATCHING_LAYOUT; 189 LIST_HEAD(free_me_list); 190 191 lo = get_layout_by_fh(clp, &args->cbl_fh, &args->cbl_stateid); 192 if (!lo) { 193 trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, NULL, 194 &args->cbl_stateid, -rv); 195 goto out; 196 } 197 198 ino = lo->plh_inode; 199 200 spin_lock(&ino->i_lock); 201 if (!pnfs_check_stateid_sequence(lo, &args->cbl_stateid)) { 202 rv = NFS4ERR_DELAY; 203 goto unlock; 204 } 205 pnfs_set_layout_stateid(lo, &args->cbl_stateid, true); 206 spin_unlock(&ino->i_lock); 207 208 pnfs_layoutcommit_inode(ino, false); 209 210 spin_lock(&ino->i_lock); 211 /* 212 * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return) 213 */ 214 if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) { 215 rv = NFS4ERR_DELAY; 216 goto unlock; 217 } 218 219 if (pnfs_mark_matching_lsegs_return(lo, &free_me_list, 220 &args->cbl_range)) { 221 rv = NFS4_OK; 222 goto unlock; 223 } 224 225 if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) { 226 NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, 227 &args->cbl_range); 228 } 229 pnfs_mark_layout_returned_if_empty(lo); 230 unlock: 231 spin_unlock(&ino->i_lock); 232 pnfs_free_lseg_list(&free_me_list); 233 /* Free all lsegs that are attached to commit buckets */ 234 nfs_commit_inode(ino, 0); 235 pnfs_put_layout_hdr(lo); 236 trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino, 237 &args->cbl_stateid, -rv); 238 iput(ino); 239 out: 240 return rv; 241 } 242 243 static u32 initiate_bulk_draining(struct nfs_client *clp, 244 struct cb_layoutrecallargs *args) 245 { 246 int stat; 247 248 if (args->cbl_recall_type == RETURN_FSID) 249 stat = pnfs_destroy_layouts_byfsid(clp, &args->cbl_fsid, true); 250 else 251 stat = pnfs_destroy_layouts_byclid(clp, true); 252 if (stat != 0) 253 return NFS4ERR_DELAY; 254 return NFS4ERR_NOMATCHING_LAYOUT; 255 } 256 257 static u32 do_callback_layoutrecall(struct nfs_client *clp, 258 struct cb_layoutrecallargs *args) 259 { 260 u32 res; 261 262 dprintk("%s enter, type=%i\n", __func__, args->cbl_recall_type); 263 if (args->cbl_recall_type == RETURN_FILE) 264 res = initiate_file_draining(clp, args); 265 else 266 res = initiate_bulk_draining(clp, args); 267 dprintk("%s returning %i\n", __func__, res); 268 return res; 269 270 } 271 272 __be32 nfs4_callback_layoutrecall(struct cb_layoutrecallargs *args, 273 void *dummy, struct cb_process_state *cps) 274 { 275 u32 res; 276 277 dprintk("%s: -->\n", __func__); 278 279 if (cps->clp) 280 res = do_callback_layoutrecall(cps->clp, args); 281 else 282 res = NFS4ERR_OP_NOT_IN_SESSION; 283 284 dprintk("%s: exit with status = %d\n", __func__, res); 285 return cpu_to_be32(res); 286 } 287 288 static void pnfs_recall_all_layouts(struct nfs_client *clp) 289 { 290 struct cb_layoutrecallargs args; 291 292 /* Pretend we got a CB_LAYOUTRECALL(ALL) */ 293 memset(&args, 0, sizeof(args)); 294 args.cbl_recall_type = RETURN_ALL; 295 /* FIXME we ignore errors, what should we do? */ 296 do_callback_layoutrecall(clp, &args); 297 } 298 299 __be32 nfs4_callback_devicenotify(struct cb_devicenotifyargs *args, 300 void *dummy, struct cb_process_state *cps) 301 { 302 int i; 303 __be32 res = 0; 304 struct nfs_client *clp = cps->clp; 305 struct nfs_server *server = NULL; 306 307 dprintk("%s: -->\n", __func__); 308 309 if (!clp) { 310 res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION); 311 goto out; 312 } 313 314 for (i = 0; i < args->ndevs; i++) { 315 struct cb_devicenotifyitem *dev = &args->devs[i]; 316 317 if (!server || 318 server->pnfs_curr_ld->id != dev->cbd_layout_type) { 319 rcu_read_lock(); 320 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) 321 if (server->pnfs_curr_ld && 322 server->pnfs_curr_ld->id == dev->cbd_layout_type) { 323 rcu_read_unlock(); 324 goto found; 325 } 326 rcu_read_unlock(); 327 dprintk("%s: layout type %u not found\n", 328 __func__, dev->cbd_layout_type); 329 continue; 330 } 331 332 found: 333 nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id); 334 } 335 336 out: 337 kfree(args->devs); 338 dprintk("%s: exit with status = %u\n", 339 __func__, be32_to_cpu(res)); 340 return res; 341 } 342 343 /* 344 * Validate the sequenceID sent by the server. 345 * Return success if the sequenceID is one more than what we last saw on 346 * this slot, accounting for wraparound. Increments the slot's sequence. 347 * 348 * We don't yet implement a duplicate request cache, instead we set the 349 * back channel ca_maxresponsesize_cached to zero. This is OK for now 350 * since we only currently implement idempotent callbacks anyway. 351 * 352 * We have a single slot backchannel at this time, so we don't bother 353 * checking the used_slots bit array on the table. The lower layer guarantees 354 * a single outstanding callback request at a time. 355 */ 356 static __be32 357 validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot, 358 const struct cb_sequenceargs * args) 359 { 360 dprintk("%s enter. slotid %u seqid %u, slot table seqid: %u\n", 361 __func__, args->csa_slotid, args->csa_sequenceid, slot->seq_nr); 362 363 if (args->csa_slotid > tbl->server_highest_slotid) 364 return htonl(NFS4ERR_BADSLOT); 365 366 /* Replay */ 367 if (args->csa_sequenceid == slot->seq_nr) { 368 dprintk("%s seqid %u is a replay\n", 369 __func__, args->csa_sequenceid); 370 if (nfs4_test_locked_slot(tbl, slot->slot_nr)) 371 return htonl(NFS4ERR_DELAY); 372 /* Signal process_op to set this error on next op */ 373 if (args->csa_cachethis == 0) 374 return htonl(NFS4ERR_RETRY_UNCACHED_REP); 375 376 /* Liar! We never allowed you to set csa_cachethis != 0 */ 377 return htonl(NFS4ERR_SEQ_FALSE_RETRY); 378 } 379 380 /* Wraparound */ 381 if (unlikely(slot->seq_nr == 0xFFFFFFFFU)) { 382 if (args->csa_sequenceid == 1) 383 return htonl(NFS4_OK); 384 } else if (likely(args->csa_sequenceid == slot->seq_nr + 1)) 385 return htonl(NFS4_OK); 386 387 /* Misordered request */ 388 return htonl(NFS4ERR_SEQ_MISORDERED); 389 } 390 391 /* 392 * For each referring call triple, check the session's slot table for 393 * a match. If the slot is in use and the sequence numbers match, the 394 * client is still waiting for a response to the original request. 395 */ 396 static bool referring_call_exists(struct nfs_client *clp, 397 uint32_t nrclists, 398 struct referring_call_list *rclists) 399 { 400 bool status = 0; 401 int i, j; 402 struct nfs4_session *session; 403 struct nfs4_slot_table *tbl; 404 struct referring_call_list *rclist; 405 struct referring_call *ref; 406 407 /* 408 * XXX When client trunking is implemented, this becomes 409 * a session lookup from within the loop 410 */ 411 session = clp->cl_session; 412 tbl = &session->fc_slot_table; 413 414 for (i = 0; i < nrclists; i++) { 415 rclist = &rclists[i]; 416 if (memcmp(session->sess_id.data, 417 rclist->rcl_sessionid.data, 418 NFS4_MAX_SESSIONID_LEN) != 0) 419 continue; 420 421 for (j = 0; j < rclist->rcl_nrefcalls; j++) { 422 ref = &rclist->rcl_refcalls[j]; 423 424 dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u " 425 "slotid %u\n", __func__, 426 ((u32 *)&rclist->rcl_sessionid.data)[0], 427 ((u32 *)&rclist->rcl_sessionid.data)[1], 428 ((u32 *)&rclist->rcl_sessionid.data)[2], 429 ((u32 *)&rclist->rcl_sessionid.data)[3], 430 ref->rc_sequenceid, ref->rc_slotid); 431 432 spin_lock(&tbl->slot_tbl_lock); 433 status = (test_bit(ref->rc_slotid, tbl->used_slots) && 434 tbl->slots[ref->rc_slotid].seq_nr == 435 ref->rc_sequenceid); 436 spin_unlock(&tbl->slot_tbl_lock); 437 if (status) 438 goto out; 439 } 440 } 441 442 out: 443 return status; 444 } 445 446 __be32 nfs4_callback_sequence(struct cb_sequenceargs *args, 447 struct cb_sequenceres *res, 448 struct cb_process_state *cps) 449 { 450 struct nfs4_slot_table *tbl; 451 struct nfs4_slot *slot; 452 struct nfs_client *clp; 453 int i; 454 __be32 status = htonl(NFS4ERR_BADSESSION); 455 456 clp = nfs4_find_client_sessionid(cps->net, args->csa_addr, 457 &args->csa_sessionid, cps->minorversion); 458 if (clp == NULL) 459 goto out; 460 461 if (!(clp->cl_session->flags & SESSION4_BACK_CHAN)) 462 goto out; 463 464 tbl = &clp->cl_session->bc_slot_table; 465 slot = tbl->slots + args->csa_slotid; 466 467 /* Set up res before grabbing the spinlock */ 468 memcpy(&res->csr_sessionid, &args->csa_sessionid, 469 sizeof(res->csr_sessionid)); 470 res->csr_sequenceid = args->csa_sequenceid; 471 res->csr_slotid = args->csa_slotid; 472 473 spin_lock(&tbl->slot_tbl_lock); 474 /* state manager is resetting the session */ 475 if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) { 476 status = htonl(NFS4ERR_DELAY); 477 /* Return NFS4ERR_BADSESSION if we're draining the session 478 * in order to reset it. 479 */ 480 if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) 481 status = htonl(NFS4ERR_BADSESSION); 482 goto out_unlock; 483 } 484 485 status = htonl(NFS4ERR_BADSLOT); 486 slot = nfs4_lookup_slot(tbl, args->csa_slotid); 487 if (IS_ERR(slot)) 488 goto out_unlock; 489 490 res->csr_highestslotid = tbl->server_highest_slotid; 491 res->csr_target_highestslotid = tbl->target_highest_slotid; 492 493 status = validate_seqid(tbl, slot, args); 494 if (status) 495 goto out_unlock; 496 if (!nfs4_try_to_lock_slot(tbl, slot)) { 497 status = htonl(NFS4ERR_DELAY); 498 goto out_unlock; 499 } 500 cps->slot = slot; 501 502 /* The ca_maxresponsesize_cached is 0 with no DRC */ 503 if (args->csa_cachethis != 0) 504 return htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE); 505 506 /* 507 * Check for pending referring calls. If a match is found, a 508 * related callback was received before the response to the original 509 * call. 510 */ 511 if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) { 512 status = htonl(NFS4ERR_DELAY); 513 goto out_unlock; 514 } 515 516 /* 517 * RFC5661 20.9.3 518 * If CB_SEQUENCE returns an error, then the state of the slot 519 * (sequence ID, cached reply) MUST NOT change. 520 */ 521 slot->seq_nr = args->csa_sequenceid; 522 out_unlock: 523 spin_unlock(&tbl->slot_tbl_lock); 524 525 out: 526 cps->clp = clp; /* put in nfs4_callback_compound */ 527 for (i = 0; i < args->csa_nrclists; i++) 528 kfree(args->csa_rclists[i].rcl_refcalls); 529 kfree(args->csa_rclists); 530 531 if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) { 532 cps->drc_status = status; 533 status = 0; 534 } else 535 res->csr_status = status; 536 537 trace_nfs4_cb_sequence(args, res, status); 538 dprintk("%s: exit with status = %d res->csr_status %d\n", __func__, 539 ntohl(status), ntohl(res->csr_status)); 540 return status; 541 } 542 543 static bool 544 validate_bitmap_values(unsigned long mask) 545 { 546 return (mask & ~RCA4_TYPE_MASK_ALL) == 0; 547 } 548 549 __be32 nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy, 550 struct cb_process_state *cps) 551 { 552 __be32 status; 553 fmode_t flags = 0; 554 555 status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION); 556 if (!cps->clp) /* set in cb_sequence */ 557 goto out; 558 559 dprintk_rcu("NFS: RECALL_ANY callback request from %s\n", 560 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); 561 562 status = cpu_to_be32(NFS4ERR_INVAL); 563 if (!validate_bitmap_values(args->craa_type_mask)) 564 goto out; 565 566 status = cpu_to_be32(NFS4_OK); 567 if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *) 568 &args->craa_type_mask)) 569 flags = FMODE_READ; 570 if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *) 571 &args->craa_type_mask)) 572 flags |= FMODE_WRITE; 573 if (test_bit(RCA4_TYPE_MASK_FILE_LAYOUT, (const unsigned long *) 574 &args->craa_type_mask)) 575 pnfs_recall_all_layouts(cps->clp); 576 if (flags) 577 nfs_expire_unused_delegation_types(cps->clp, flags); 578 out: 579 dprintk("%s: exit with status = %d\n", __func__, ntohl(status)); 580 return status; 581 } 582 583 /* Reduce the fore channel's max_slots to the target value */ 584 __be32 nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy, 585 struct cb_process_state *cps) 586 { 587 struct nfs4_slot_table *fc_tbl; 588 __be32 status; 589 590 status = htonl(NFS4ERR_OP_NOT_IN_SESSION); 591 if (!cps->clp) /* set in cb_sequence */ 592 goto out; 593 594 dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n", 595 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR), 596 args->crsa_target_highest_slotid); 597 598 fc_tbl = &cps->clp->cl_session->fc_slot_table; 599 600 status = htonl(NFS4_OK); 601 602 nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid); 603 nfs41_notify_server(cps->clp); 604 out: 605 dprintk("%s: exit with status = %d\n", __func__, ntohl(status)); 606 return status; 607 } 608 #endif /* CONFIG_NFS_V4_1 */ 609