1 /* 2 * Copyright (c) 2007 Oracle. All rights reserved. 3 * 4 * This software is available to you under a choice of one of two 5 * licenses. You may choose to be licensed under the terms of the GNU 6 * General Public License (GPL) Version 2, available from the file 7 * COPYING in the main directory of this source tree, or the 8 * OpenIB.org BSD license below: 9 * 10 * Redistribution and use in source and binary forms, with or 11 * without modification, are permitted provided that the following 12 * conditions are met: 13 * 14 * - Redistributions of source code must retain the above 15 * copyright notice, this list of conditions and the following 16 * disclaimer. 17 * 18 * - Redistributions in binary form must reproduce the above 19 * copyright notice, this list of conditions and the following 20 * disclaimer in the documentation and/or other materials 21 * provided with the distribution. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 30 * SOFTWARE. 31 * 32 */ 33 #include <linux/pagemap.h> 34 #include <linux/rbtree.h> 35 #include <linux/dma-mapping.h> /* for DMA_*_DEVICE */ 36 37 #include "rdma.h" 38 39 /* 40 * XXX 41 * - build with sparse 42 * - should we limit the size of a mr region? let transport return failure? 43 * - should we detect duplicate keys on a socket? hmm. 44 * - an rdma is an mlock, apply rlimit? 45 */ 46 47 /* 48 * get the number of pages by looking at the page indices that the start and 49 * end addresses fall in. 50 * 51 * Returns 0 if the vec is invalid. It is invalid if the number of bytes 52 * causes the address to wrap or overflows an unsigned int. This comes 53 * from being stored in the 'length' member of 'struct scatterlist'. 54 */ 55 static unsigned int rds_pages_in_vec(struct rds_iovec *vec) 56 { 57 if ((vec->addr + vec->bytes <= vec->addr) || 58 (vec->bytes > (u64)UINT_MAX)) 59 return 0; 60 61 return ((vec->addr + vec->bytes + PAGE_SIZE - 1) >> PAGE_SHIFT) - 62 (vec->addr >> PAGE_SHIFT); 63 } 64 65 static struct rds_mr *rds_mr_tree_walk(struct rb_root *root, u64 key, 66 struct rds_mr *insert) 67 { 68 struct rb_node **p = &root->rb_node; 69 struct rb_node *parent = NULL; 70 struct rds_mr *mr; 71 72 while (*p) { 73 parent = *p; 74 mr = rb_entry(parent, struct rds_mr, r_rb_node); 75 76 if (key < mr->r_key) 77 p = &(*p)->rb_left; 78 else if (key > mr->r_key) 79 p = &(*p)->rb_right; 80 else 81 return mr; 82 } 83 84 if (insert) { 85 rb_link_node(&insert->r_rb_node, parent, p); 86 rb_insert_color(&insert->r_rb_node, root); 87 atomic_inc(&insert->r_refcount); 88 } 89 return NULL; 90 } 91 92 /* 93 * Destroy the transport-specific part of a MR. 94 */ 95 static void rds_destroy_mr(struct rds_mr *mr) 96 { 97 struct rds_sock *rs = mr->r_sock; 98 void *trans_private = NULL; 99 unsigned long flags; 100 101 rdsdebug("RDS: destroy mr key is %x refcnt %u\n", 102 mr->r_key, atomic_read(&mr->r_refcount)); 103 104 if (test_and_set_bit(RDS_MR_DEAD, &mr->r_state)) 105 return; 106 107 spin_lock_irqsave(&rs->rs_rdma_lock, flags); 108 if (!RB_EMPTY_NODE(&mr->r_rb_node)) 109 rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys); 110 trans_private = mr->r_trans_private; 111 mr->r_trans_private = NULL; 112 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 113 114 if (trans_private) 115 mr->r_trans->free_mr(trans_private, mr->r_invalidate); 116 } 117 118 void __rds_put_mr_final(struct rds_mr *mr) 119 { 120 rds_destroy_mr(mr); 121 kfree(mr); 122 } 123 124 /* 125 * By the time this is called we can't have any more ioctls called on 126 * the socket so we don't need to worry about racing with others. 127 */ 128 void rds_rdma_drop_keys(struct rds_sock *rs) 129 { 130 struct rds_mr *mr; 131 struct rb_node *node; 132 133 /* Release any MRs associated with this socket */ 134 while ((node = rb_first(&rs->rs_rdma_keys))) { 135 mr = container_of(node, struct rds_mr, r_rb_node); 136 if (mr->r_trans == rs->rs_transport) 137 mr->r_invalidate = 0; 138 rds_mr_put(mr); 139 } 140 141 if (rs->rs_transport && rs->rs_transport->flush_mrs) 142 rs->rs_transport->flush_mrs(); 143 } 144 145 /* 146 * Helper function to pin user pages. 147 */ 148 static int rds_pin_pages(unsigned long user_addr, unsigned int nr_pages, 149 struct page **pages, int write) 150 { 151 int ret; 152 153 down_read(¤t->mm->mmap_sem); 154 ret = get_user_pages(current, current->mm, user_addr, 155 nr_pages, write, 0, pages, NULL); 156 up_read(¤t->mm->mmap_sem); 157 158 if (0 <= ret && (unsigned) ret < nr_pages) { 159 while (ret--) 160 put_page(pages[ret]); 161 ret = -EFAULT; 162 } 163 164 return ret; 165 } 166 167 static int __rds_rdma_map(struct rds_sock *rs, struct rds_get_mr_args *args, 168 u64 *cookie_ret, struct rds_mr **mr_ret) 169 { 170 struct rds_mr *mr = NULL, *found; 171 unsigned int nr_pages; 172 struct page **pages = NULL; 173 struct scatterlist *sg; 174 void *trans_private; 175 unsigned long flags; 176 rds_rdma_cookie_t cookie; 177 unsigned int nents; 178 long i; 179 int ret; 180 181 if (rs->rs_bound_addr == 0) { 182 ret = -ENOTCONN; /* XXX not a great errno */ 183 goto out; 184 } 185 186 if (rs->rs_transport->get_mr == NULL) { 187 ret = -EOPNOTSUPP; 188 goto out; 189 } 190 191 nr_pages = rds_pages_in_vec(&args->vec); 192 if (nr_pages == 0) { 193 ret = -EINVAL; 194 goto out; 195 } 196 197 rdsdebug("RDS: get_mr addr %llx len %llu nr_pages %u\n", 198 args->vec.addr, args->vec.bytes, nr_pages); 199 200 /* XXX clamp nr_pages to limit the size of this alloc? */ 201 pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL); 202 if (pages == NULL) { 203 ret = -ENOMEM; 204 goto out; 205 } 206 207 mr = kzalloc(sizeof(struct rds_mr), GFP_KERNEL); 208 if (mr == NULL) { 209 ret = -ENOMEM; 210 goto out; 211 } 212 213 atomic_set(&mr->r_refcount, 1); 214 RB_CLEAR_NODE(&mr->r_rb_node); 215 mr->r_trans = rs->rs_transport; 216 mr->r_sock = rs; 217 218 if (args->flags & RDS_RDMA_USE_ONCE) 219 mr->r_use_once = 1; 220 if (args->flags & RDS_RDMA_INVALIDATE) 221 mr->r_invalidate = 1; 222 if (args->flags & RDS_RDMA_READWRITE) 223 mr->r_write = 1; 224 225 /* 226 * Pin the pages that make up the user buffer and transfer the page 227 * pointers to the mr's sg array. We check to see if we've mapped 228 * the whole region after transferring the partial page references 229 * to the sg array so that we can have one page ref cleanup path. 230 * 231 * For now we have no flag that tells us whether the mapping is 232 * r/o or r/w. We need to assume r/w, or we'll do a lot of RDMA to 233 * the zero page. 234 */ 235 ret = rds_pin_pages(args->vec.addr & PAGE_MASK, nr_pages, pages, 1); 236 if (ret < 0) 237 goto out; 238 239 nents = ret; 240 sg = kcalloc(nents, sizeof(*sg), GFP_KERNEL); 241 if (sg == NULL) { 242 ret = -ENOMEM; 243 goto out; 244 } 245 WARN_ON(!nents); 246 sg_init_table(sg, nents); 247 248 /* Stick all pages into the scatterlist */ 249 for (i = 0 ; i < nents; i++) 250 sg_set_page(&sg[i], pages[i], PAGE_SIZE, 0); 251 252 rdsdebug("RDS: trans_private nents is %u\n", nents); 253 254 /* Obtain a transport specific MR. If this succeeds, the 255 * s/g list is now owned by the MR. 256 * Note that dma_map() implies that pending writes are 257 * flushed to RAM, so no dma_sync is needed here. */ 258 trans_private = rs->rs_transport->get_mr(sg, nents, rs, 259 &mr->r_key); 260 261 if (IS_ERR(trans_private)) { 262 for (i = 0 ; i < nents; i++) 263 put_page(sg_page(&sg[i])); 264 kfree(sg); 265 ret = PTR_ERR(trans_private); 266 goto out; 267 } 268 269 mr->r_trans_private = trans_private; 270 271 rdsdebug("RDS: get_mr put_user key is %x cookie_addr %p\n", 272 mr->r_key, (void *)(unsigned long) args->cookie_addr); 273 274 /* The user may pass us an unaligned address, but we can only 275 * map page aligned regions. So we keep the offset, and build 276 * a 64bit cookie containing <R_Key, offset> and pass that 277 * around. */ 278 cookie = rds_rdma_make_cookie(mr->r_key, args->vec.addr & ~PAGE_MASK); 279 if (cookie_ret) 280 *cookie_ret = cookie; 281 282 if (args->cookie_addr && put_user(cookie, (u64 __user *)(unsigned long) args->cookie_addr)) { 283 ret = -EFAULT; 284 goto out; 285 } 286 287 /* Inserting the new MR into the rbtree bumps its 288 * reference count. */ 289 spin_lock_irqsave(&rs->rs_rdma_lock, flags); 290 found = rds_mr_tree_walk(&rs->rs_rdma_keys, mr->r_key, mr); 291 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 292 293 BUG_ON(found && found != mr); 294 295 rdsdebug("RDS: get_mr key is %x\n", mr->r_key); 296 if (mr_ret) { 297 atomic_inc(&mr->r_refcount); 298 *mr_ret = mr; 299 } 300 301 ret = 0; 302 out: 303 kfree(pages); 304 if (mr) 305 rds_mr_put(mr); 306 return ret; 307 } 308 309 int rds_get_mr(struct rds_sock *rs, char __user *optval, int optlen) 310 { 311 struct rds_get_mr_args args; 312 313 if (optlen != sizeof(struct rds_get_mr_args)) 314 return -EINVAL; 315 316 if (copy_from_user(&args, (struct rds_get_mr_args __user *)optval, 317 sizeof(struct rds_get_mr_args))) 318 return -EFAULT; 319 320 return __rds_rdma_map(rs, &args, NULL, NULL); 321 } 322 323 /* 324 * Free the MR indicated by the given R_Key 325 */ 326 int rds_free_mr(struct rds_sock *rs, char __user *optval, int optlen) 327 { 328 struct rds_free_mr_args args; 329 struct rds_mr *mr; 330 unsigned long flags; 331 332 if (optlen != sizeof(struct rds_free_mr_args)) 333 return -EINVAL; 334 335 if (copy_from_user(&args, (struct rds_free_mr_args __user *)optval, 336 sizeof(struct rds_free_mr_args))) 337 return -EFAULT; 338 339 /* Special case - a null cookie means flush all unused MRs */ 340 if (args.cookie == 0) { 341 if (!rs->rs_transport || !rs->rs_transport->flush_mrs) 342 return -EINVAL; 343 rs->rs_transport->flush_mrs(); 344 return 0; 345 } 346 347 /* Look up the MR given its R_key and remove it from the rbtree 348 * so nobody else finds it. 349 * This should also prevent races with rds_rdma_unuse. 350 */ 351 spin_lock_irqsave(&rs->rs_rdma_lock, flags); 352 mr = rds_mr_tree_walk(&rs->rs_rdma_keys, rds_rdma_cookie_key(args.cookie), NULL); 353 if (mr) { 354 rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys); 355 RB_CLEAR_NODE(&mr->r_rb_node); 356 if (args.flags & RDS_RDMA_INVALIDATE) 357 mr->r_invalidate = 1; 358 } 359 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 360 361 if (!mr) 362 return -EINVAL; 363 364 /* 365 * call rds_destroy_mr() ourselves so that we're sure it's done by the time 366 * we return. If we let rds_mr_put() do it it might not happen until 367 * someone else drops their ref. 368 */ 369 rds_destroy_mr(mr); 370 rds_mr_put(mr); 371 return 0; 372 } 373 374 /* 375 * This is called when we receive an extension header that 376 * tells us this MR was used. It allows us to implement 377 * use_once semantics 378 */ 379 void rds_rdma_unuse(struct rds_sock *rs, u32 r_key, int force) 380 { 381 struct rds_mr *mr; 382 unsigned long flags; 383 int zot_me = 0; 384 385 spin_lock_irqsave(&rs->rs_rdma_lock, flags); 386 mr = rds_mr_tree_walk(&rs->rs_rdma_keys, r_key, NULL); 387 if (mr && (mr->r_use_once || force)) { 388 rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys); 389 RB_CLEAR_NODE(&mr->r_rb_node); 390 zot_me = 1; 391 } else if (mr) 392 atomic_inc(&mr->r_refcount); 393 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 394 395 /* May have to issue a dma_sync on this memory region. 396 * Note we could avoid this if the operation was a RDMA READ, 397 * but at this point we can't tell. */ 398 if (mr != NULL) { 399 if (mr->r_trans->sync_mr) 400 mr->r_trans->sync_mr(mr->r_trans_private, DMA_FROM_DEVICE); 401 402 /* If the MR was marked as invalidate, this will 403 * trigger an async flush. */ 404 if (zot_me) 405 rds_destroy_mr(mr); 406 rds_mr_put(mr); 407 } 408 } 409 410 void rds_rdma_free_op(struct rds_rdma_op *ro) 411 { 412 unsigned int i; 413 414 for (i = 0; i < ro->r_nents; i++) { 415 struct page *page = sg_page(&ro->r_sg[i]); 416 417 /* Mark page dirty if it was possibly modified, which 418 * is the case for a RDMA_READ which copies from remote 419 * to local memory */ 420 if (!ro->r_write) 421 set_page_dirty(page); 422 put_page(page); 423 } 424 425 kfree(ro->r_notifier); 426 kfree(ro); 427 } 428 429 /* 430 * args is a pointer to an in-kernel copy in the sendmsg cmsg. 431 */ 432 static struct rds_rdma_op *rds_rdma_prepare(struct rds_sock *rs, 433 struct rds_rdma_args *args) 434 { 435 struct rds_iovec vec; 436 struct rds_rdma_op *op = NULL; 437 unsigned int nr_pages; 438 unsigned int max_pages; 439 unsigned int nr_bytes; 440 struct page **pages = NULL; 441 struct rds_iovec __user *local_vec; 442 struct scatterlist *sg; 443 unsigned int nr; 444 unsigned int i, j; 445 int ret; 446 447 448 if (rs->rs_bound_addr == 0) { 449 ret = -ENOTCONN; /* XXX not a great errno */ 450 goto out; 451 } 452 453 if (args->nr_local > (u64)UINT_MAX) { 454 ret = -EMSGSIZE; 455 goto out; 456 } 457 458 nr_pages = 0; 459 max_pages = 0; 460 461 local_vec = (struct rds_iovec __user *)(unsigned long) args->local_vec_addr; 462 463 /* figure out the number of pages in the vector */ 464 for (i = 0; i < args->nr_local; i++) { 465 if (copy_from_user(&vec, &local_vec[i], 466 sizeof(struct rds_iovec))) { 467 ret = -EFAULT; 468 goto out; 469 } 470 471 nr = rds_pages_in_vec(&vec); 472 if (nr == 0) { 473 ret = -EINVAL; 474 goto out; 475 } 476 477 max_pages = max(nr, max_pages); 478 nr_pages += nr; 479 } 480 481 pages = kcalloc(max_pages, sizeof(struct page *), GFP_KERNEL); 482 if (pages == NULL) { 483 ret = -ENOMEM; 484 goto out; 485 } 486 487 op = kzalloc(offsetof(struct rds_rdma_op, r_sg[nr_pages]), GFP_KERNEL); 488 if (op == NULL) { 489 ret = -ENOMEM; 490 goto out; 491 } 492 493 op->r_write = !!(args->flags & RDS_RDMA_READWRITE); 494 op->r_fence = !!(args->flags & RDS_RDMA_FENCE); 495 op->r_notify = !!(args->flags & RDS_RDMA_NOTIFY_ME); 496 op->r_recverr = rs->rs_recverr; 497 WARN_ON(!nr_pages); 498 sg_init_table(op->r_sg, nr_pages); 499 500 if (op->r_notify || op->r_recverr) { 501 /* We allocate an uninitialized notifier here, because 502 * we don't want to do that in the completion handler. We 503 * would have to use GFP_ATOMIC there, and don't want to deal 504 * with failed allocations. 505 */ 506 op->r_notifier = kmalloc(sizeof(struct rds_notifier), GFP_KERNEL); 507 if (!op->r_notifier) { 508 ret = -ENOMEM; 509 goto out; 510 } 511 op->r_notifier->n_user_token = args->user_token; 512 op->r_notifier->n_status = RDS_RDMA_SUCCESS; 513 } 514 515 /* The cookie contains the R_Key of the remote memory region, and 516 * optionally an offset into it. This is how we implement RDMA into 517 * unaligned memory. 518 * When setting up the RDMA, we need to add that offset to the 519 * destination address (which is really an offset into the MR) 520 * FIXME: We may want to move this into ib_rdma.c 521 */ 522 op->r_key = rds_rdma_cookie_key(args->cookie); 523 op->r_remote_addr = args->remote_vec.addr + rds_rdma_cookie_offset(args->cookie); 524 525 nr_bytes = 0; 526 527 rdsdebug("RDS: rdma prepare nr_local %llu rva %llx rkey %x\n", 528 (unsigned long long)args->nr_local, 529 (unsigned long long)args->remote_vec.addr, 530 op->r_key); 531 532 for (i = 0; i < args->nr_local; i++) { 533 if (copy_from_user(&vec, &local_vec[i], 534 sizeof(struct rds_iovec))) { 535 ret = -EFAULT; 536 goto out; 537 } 538 539 nr = rds_pages_in_vec(&vec); 540 if (nr == 0) { 541 ret = -EINVAL; 542 goto out; 543 } 544 545 rs->rs_user_addr = vec.addr; 546 rs->rs_user_bytes = vec.bytes; 547 548 /* did the user change the vec under us? */ 549 if (nr > max_pages || op->r_nents + nr > nr_pages) { 550 ret = -EINVAL; 551 goto out; 552 } 553 /* If it's a WRITE operation, we want to pin the pages for reading. 554 * If it's a READ operation, we need to pin the pages for writing. 555 */ 556 ret = rds_pin_pages(vec.addr & PAGE_MASK, nr, pages, !op->r_write); 557 if (ret < 0) 558 goto out; 559 560 rdsdebug("RDS: nr_bytes %u nr %u vec.bytes %llu vec.addr %llx\n", 561 nr_bytes, nr, vec.bytes, vec.addr); 562 563 nr_bytes += vec.bytes; 564 565 for (j = 0; j < nr; j++) { 566 unsigned int offset = vec.addr & ~PAGE_MASK; 567 568 sg = &op->r_sg[op->r_nents + j]; 569 sg_set_page(sg, pages[j], 570 min_t(unsigned int, vec.bytes, PAGE_SIZE - offset), 571 offset); 572 573 rdsdebug("RDS: sg->offset %x sg->len %x vec.addr %llx vec.bytes %llu\n", 574 sg->offset, sg->length, vec.addr, vec.bytes); 575 576 vec.addr += sg->length; 577 vec.bytes -= sg->length; 578 } 579 580 op->r_nents += nr; 581 } 582 583 584 if (nr_bytes > args->remote_vec.bytes) { 585 rdsdebug("RDS nr_bytes %u remote_bytes %u do not match\n", 586 nr_bytes, 587 (unsigned int) args->remote_vec.bytes); 588 ret = -EINVAL; 589 goto out; 590 } 591 op->r_bytes = nr_bytes; 592 593 ret = 0; 594 out: 595 kfree(pages); 596 if (ret) { 597 if (op) 598 rds_rdma_free_op(op); 599 op = ERR_PTR(ret); 600 } 601 return op; 602 } 603 604 /* 605 * The application asks for a RDMA transfer. 606 * Extract all arguments and set up the rdma_op 607 */ 608 int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm, 609 struct cmsghdr *cmsg) 610 { 611 struct rds_rdma_op *op; 612 613 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_rdma_args)) 614 || rm->m_rdma_op != NULL) 615 return -EINVAL; 616 617 op = rds_rdma_prepare(rs, CMSG_DATA(cmsg)); 618 if (IS_ERR(op)) 619 return PTR_ERR(op); 620 rds_stats_inc(s_send_rdma); 621 rm->m_rdma_op = op; 622 return 0; 623 } 624 625 /* 626 * The application wants us to pass an RDMA destination (aka MR) 627 * to the remote 628 */ 629 int rds_cmsg_rdma_dest(struct rds_sock *rs, struct rds_message *rm, 630 struct cmsghdr *cmsg) 631 { 632 unsigned long flags; 633 struct rds_mr *mr; 634 u32 r_key; 635 int err = 0; 636 637 if (cmsg->cmsg_len < CMSG_LEN(sizeof(rds_rdma_cookie_t)) 638 || rm->m_rdma_cookie != 0) 639 return -EINVAL; 640 641 memcpy(&rm->m_rdma_cookie, CMSG_DATA(cmsg), sizeof(rm->m_rdma_cookie)); 642 643 /* We are reusing a previously mapped MR here. Most likely, the 644 * application has written to the buffer, so we need to explicitly 645 * flush those writes to RAM. Otherwise the HCA may not see them 646 * when doing a DMA from that buffer. 647 */ 648 r_key = rds_rdma_cookie_key(rm->m_rdma_cookie); 649 650 spin_lock_irqsave(&rs->rs_rdma_lock, flags); 651 mr = rds_mr_tree_walk(&rs->rs_rdma_keys, r_key, NULL); 652 if (mr == NULL) 653 err = -EINVAL; /* invalid r_key */ 654 else 655 atomic_inc(&mr->r_refcount); 656 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 657 658 if (mr) { 659 mr->r_trans->sync_mr(mr->r_trans_private, DMA_TO_DEVICE); 660 rm->m_rdma_mr = mr; 661 } 662 return err; 663 } 664 665 /* 666 * The application passes us an address range it wants to enable RDMA 667 * to/from. We map the area, and save the <R_Key,offset> pair 668 * in rm->m_rdma_cookie. This causes it to be sent along to the peer 669 * in an extension header. 670 */ 671 int rds_cmsg_rdma_map(struct rds_sock *rs, struct rds_message *rm, 672 struct cmsghdr *cmsg) 673 { 674 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_get_mr_args)) 675 || rm->m_rdma_cookie != 0) 676 return -EINVAL; 677 678 return __rds_rdma_map(rs, CMSG_DATA(cmsg), &rm->m_rdma_cookie, &rm->m_rdma_mr); 679 } 680