1 /* 2 * Copyright (c) 2007, 2017 Oracle and/or its affiliates. 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/slab.h> 35 #include <linux/rbtree.h> 36 #include <linux/dma-mapping.h> /* for DMA_*_DEVICE */ 37 38 #include "rds.h" 39 40 /* 41 * XXX 42 * - build with sparse 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 refcount_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, refcount_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 unsigned long flags; 133 134 /* Release any MRs associated with this socket */ 135 spin_lock_irqsave(&rs->rs_rdma_lock, flags); 136 while ((node = rb_first(&rs->rs_rdma_keys))) { 137 mr = rb_entry(node, struct rds_mr, r_rb_node); 138 if (mr->r_trans == rs->rs_transport) 139 mr->r_invalidate = 0; 140 rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys); 141 RB_CLEAR_NODE(&mr->r_rb_node); 142 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 143 rds_destroy_mr(mr); 144 rds_mr_put(mr); 145 spin_lock_irqsave(&rs->rs_rdma_lock, flags); 146 } 147 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 148 149 if (rs->rs_transport && rs->rs_transport->flush_mrs) 150 rs->rs_transport->flush_mrs(); 151 } 152 153 /* 154 * Helper function to pin user pages. 155 */ 156 static int rds_pin_pages(unsigned long user_addr, unsigned int nr_pages, 157 struct page **pages, int write) 158 { 159 int ret; 160 161 ret = get_user_pages_fast(user_addr, nr_pages, write ? FOLL_WRITE : 0, 162 pages); 163 164 if (ret >= 0 && ret < nr_pages) { 165 while (ret--) 166 put_page(pages[ret]); 167 ret = -EFAULT; 168 } 169 170 return ret; 171 } 172 173 static int __rds_rdma_map(struct rds_sock *rs, struct rds_get_mr_args *args, 174 u64 *cookie_ret, struct rds_mr **mr_ret, 175 struct rds_conn_path *cp) 176 { 177 struct rds_mr *mr = NULL, *found; 178 unsigned int nr_pages; 179 struct page **pages = NULL; 180 struct scatterlist *sg; 181 void *trans_private; 182 unsigned long flags; 183 rds_rdma_cookie_t cookie; 184 unsigned int nents; 185 long i; 186 int ret; 187 188 if (ipv6_addr_any(&rs->rs_bound_addr) || !rs->rs_transport) { 189 ret = -ENOTCONN; /* XXX not a great errno */ 190 goto out; 191 } 192 193 if (!rs->rs_transport->get_mr) { 194 ret = -EOPNOTSUPP; 195 goto out; 196 } 197 198 nr_pages = rds_pages_in_vec(&args->vec); 199 if (nr_pages == 0) { 200 ret = -EINVAL; 201 goto out; 202 } 203 204 /* Restrict the size of mr irrespective of underlying transport 205 * To account for unaligned mr regions, subtract one from nr_pages 206 */ 207 if ((nr_pages - 1) > (RDS_MAX_MSG_SIZE >> PAGE_SHIFT)) { 208 ret = -EMSGSIZE; 209 goto out; 210 } 211 212 rdsdebug("RDS: get_mr addr %llx len %llu nr_pages %u\n", 213 args->vec.addr, args->vec.bytes, nr_pages); 214 215 /* XXX clamp nr_pages to limit the size of this alloc? */ 216 pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL); 217 if (!pages) { 218 ret = -ENOMEM; 219 goto out; 220 } 221 222 mr = kzalloc(sizeof(struct rds_mr), GFP_KERNEL); 223 if (!mr) { 224 ret = -ENOMEM; 225 goto out; 226 } 227 228 refcount_set(&mr->r_refcount, 1); 229 RB_CLEAR_NODE(&mr->r_rb_node); 230 mr->r_trans = rs->rs_transport; 231 mr->r_sock = rs; 232 233 if (args->flags & RDS_RDMA_USE_ONCE) 234 mr->r_use_once = 1; 235 if (args->flags & RDS_RDMA_INVALIDATE) 236 mr->r_invalidate = 1; 237 if (args->flags & RDS_RDMA_READWRITE) 238 mr->r_write = 1; 239 240 /* 241 * Pin the pages that make up the user buffer and transfer the page 242 * pointers to the mr's sg array. We check to see if we've mapped 243 * the whole region after transferring the partial page references 244 * to the sg array so that we can have one page ref cleanup path. 245 * 246 * For now we have no flag that tells us whether the mapping is 247 * r/o or r/w. We need to assume r/w, or we'll do a lot of RDMA to 248 * the zero page. 249 */ 250 ret = rds_pin_pages(args->vec.addr, nr_pages, pages, 1); 251 if (ret < 0) 252 goto out; 253 254 nents = ret; 255 sg = kcalloc(nents, sizeof(*sg), GFP_KERNEL); 256 if (!sg) { 257 ret = -ENOMEM; 258 goto out; 259 } 260 WARN_ON(!nents); 261 sg_init_table(sg, nents); 262 263 /* Stick all pages into the scatterlist */ 264 for (i = 0 ; i < nents; i++) 265 sg_set_page(&sg[i], pages[i], PAGE_SIZE, 0); 266 267 rdsdebug("RDS: trans_private nents is %u\n", nents); 268 269 /* Obtain a transport specific MR. If this succeeds, the 270 * s/g list is now owned by the MR. 271 * Note that dma_map() implies that pending writes are 272 * flushed to RAM, so no dma_sync is needed here. */ 273 trans_private = rs->rs_transport->get_mr(sg, nents, rs, 274 &mr->r_key, 275 cp ? cp->cp_conn : NULL); 276 277 if (IS_ERR(trans_private)) { 278 for (i = 0 ; i < nents; i++) 279 put_page(sg_page(&sg[i])); 280 kfree(sg); 281 ret = PTR_ERR(trans_private); 282 goto out; 283 } 284 285 mr->r_trans_private = trans_private; 286 287 rdsdebug("RDS: get_mr put_user key is %x cookie_addr %p\n", 288 mr->r_key, (void *)(unsigned long) args->cookie_addr); 289 290 /* The user may pass us an unaligned address, but we can only 291 * map page aligned regions. So we keep the offset, and build 292 * a 64bit cookie containing <R_Key, offset> and pass that 293 * around. */ 294 cookie = rds_rdma_make_cookie(mr->r_key, args->vec.addr & ~PAGE_MASK); 295 if (cookie_ret) 296 *cookie_ret = cookie; 297 298 if (args->cookie_addr && put_user(cookie, (u64 __user *)(unsigned long) args->cookie_addr)) { 299 ret = -EFAULT; 300 goto out; 301 } 302 303 /* Inserting the new MR into the rbtree bumps its 304 * reference count. */ 305 spin_lock_irqsave(&rs->rs_rdma_lock, flags); 306 found = rds_mr_tree_walk(&rs->rs_rdma_keys, mr->r_key, mr); 307 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 308 309 BUG_ON(found && found != mr); 310 311 rdsdebug("RDS: get_mr key is %x\n", mr->r_key); 312 if (mr_ret) { 313 refcount_inc(&mr->r_refcount); 314 *mr_ret = mr; 315 } 316 317 ret = 0; 318 out: 319 kfree(pages); 320 if (mr) 321 rds_mr_put(mr); 322 return ret; 323 } 324 325 int rds_get_mr(struct rds_sock *rs, char __user *optval, int optlen) 326 { 327 struct rds_get_mr_args args; 328 329 if (optlen != sizeof(struct rds_get_mr_args)) 330 return -EINVAL; 331 332 if (copy_from_user(&args, (struct rds_get_mr_args __user *)optval, 333 sizeof(struct rds_get_mr_args))) 334 return -EFAULT; 335 336 return __rds_rdma_map(rs, &args, NULL, NULL, NULL); 337 } 338 339 int rds_get_mr_for_dest(struct rds_sock *rs, char __user *optval, int optlen) 340 { 341 struct rds_get_mr_for_dest_args args; 342 struct rds_get_mr_args new_args; 343 344 if (optlen != sizeof(struct rds_get_mr_for_dest_args)) 345 return -EINVAL; 346 347 if (copy_from_user(&args, (struct rds_get_mr_for_dest_args __user *)optval, 348 sizeof(struct rds_get_mr_for_dest_args))) 349 return -EFAULT; 350 351 /* 352 * Initially, just behave like get_mr(). 353 * TODO: Implement get_mr as wrapper around this 354 * and deprecate it. 355 */ 356 new_args.vec = args.vec; 357 new_args.cookie_addr = args.cookie_addr; 358 new_args.flags = args.flags; 359 360 return __rds_rdma_map(rs, &new_args, NULL, NULL, NULL); 361 } 362 363 /* 364 * Free the MR indicated by the given R_Key 365 */ 366 int rds_free_mr(struct rds_sock *rs, char __user *optval, int optlen) 367 { 368 struct rds_free_mr_args args; 369 struct rds_mr *mr; 370 unsigned long flags; 371 372 if (optlen != sizeof(struct rds_free_mr_args)) 373 return -EINVAL; 374 375 if (copy_from_user(&args, (struct rds_free_mr_args __user *)optval, 376 sizeof(struct rds_free_mr_args))) 377 return -EFAULT; 378 379 /* Special case - a null cookie means flush all unused MRs */ 380 if (args.cookie == 0) { 381 if (!rs->rs_transport || !rs->rs_transport->flush_mrs) 382 return -EINVAL; 383 rs->rs_transport->flush_mrs(); 384 return 0; 385 } 386 387 /* Look up the MR given its R_key and remove it from the rbtree 388 * so nobody else finds it. 389 * This should also prevent races with rds_rdma_unuse. 390 */ 391 spin_lock_irqsave(&rs->rs_rdma_lock, flags); 392 mr = rds_mr_tree_walk(&rs->rs_rdma_keys, rds_rdma_cookie_key(args.cookie), NULL); 393 if (mr) { 394 rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys); 395 RB_CLEAR_NODE(&mr->r_rb_node); 396 if (args.flags & RDS_RDMA_INVALIDATE) 397 mr->r_invalidate = 1; 398 } 399 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 400 401 if (!mr) 402 return -EINVAL; 403 404 /* 405 * call rds_destroy_mr() ourselves so that we're sure it's done by the time 406 * we return. If we let rds_mr_put() do it it might not happen until 407 * someone else drops their ref. 408 */ 409 rds_destroy_mr(mr); 410 rds_mr_put(mr); 411 return 0; 412 } 413 414 /* 415 * This is called when we receive an extension header that 416 * tells us this MR was used. It allows us to implement 417 * use_once semantics 418 */ 419 void rds_rdma_unuse(struct rds_sock *rs, u32 r_key, int force) 420 { 421 struct rds_mr *mr; 422 unsigned long flags; 423 int zot_me = 0; 424 425 spin_lock_irqsave(&rs->rs_rdma_lock, flags); 426 mr = rds_mr_tree_walk(&rs->rs_rdma_keys, r_key, NULL); 427 if (!mr) { 428 pr_debug("rds: trying to unuse MR with unknown r_key %u!\n", 429 r_key); 430 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 431 return; 432 } 433 434 if (mr->r_use_once || force) { 435 rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys); 436 RB_CLEAR_NODE(&mr->r_rb_node); 437 zot_me = 1; 438 } 439 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 440 441 /* May have to issue a dma_sync on this memory region. 442 * Note we could avoid this if the operation was a RDMA READ, 443 * but at this point we can't tell. */ 444 if (mr->r_trans->sync_mr) 445 mr->r_trans->sync_mr(mr->r_trans_private, DMA_FROM_DEVICE); 446 447 /* If the MR was marked as invalidate, this will 448 * trigger an async flush. */ 449 if (zot_me) { 450 rds_destroy_mr(mr); 451 rds_mr_put(mr); 452 } 453 } 454 455 void rds_rdma_free_op(struct rm_rdma_op *ro) 456 { 457 unsigned int i; 458 459 for (i = 0; i < ro->op_nents; i++) { 460 struct page *page = sg_page(&ro->op_sg[i]); 461 462 /* Mark page dirty if it was possibly modified, which 463 * is the case for a RDMA_READ which copies from remote 464 * to local memory */ 465 if (!ro->op_write) { 466 WARN_ON(!page->mapping && irqs_disabled()); 467 set_page_dirty(page); 468 } 469 put_page(page); 470 } 471 472 kfree(ro->op_notifier); 473 ro->op_notifier = NULL; 474 ro->op_active = 0; 475 } 476 477 void rds_atomic_free_op(struct rm_atomic_op *ao) 478 { 479 struct page *page = sg_page(ao->op_sg); 480 481 /* Mark page dirty if it was possibly modified, which 482 * is the case for a RDMA_READ which copies from remote 483 * to local memory */ 484 set_page_dirty(page); 485 put_page(page); 486 487 kfree(ao->op_notifier); 488 ao->op_notifier = NULL; 489 ao->op_active = 0; 490 } 491 492 493 /* 494 * Count the number of pages needed to describe an incoming iovec array. 495 */ 496 static int rds_rdma_pages(struct rds_iovec iov[], int nr_iovecs) 497 { 498 int tot_pages = 0; 499 unsigned int nr_pages; 500 unsigned int i; 501 502 /* figure out the number of pages in the vector */ 503 for (i = 0; i < nr_iovecs; i++) { 504 nr_pages = rds_pages_in_vec(&iov[i]); 505 if (nr_pages == 0) 506 return -EINVAL; 507 508 tot_pages += nr_pages; 509 510 /* 511 * nr_pages for one entry is limited to (UINT_MAX>>PAGE_SHIFT)+1, 512 * so tot_pages cannot overflow without first going negative. 513 */ 514 if (tot_pages < 0) 515 return -EINVAL; 516 } 517 518 return tot_pages; 519 } 520 521 int rds_rdma_extra_size(struct rds_rdma_args *args, 522 struct rds_iov_vector *iov) 523 { 524 struct rds_iovec *vec; 525 struct rds_iovec __user *local_vec; 526 int tot_pages = 0; 527 unsigned int nr_pages; 528 unsigned int i; 529 530 local_vec = (struct rds_iovec __user *)(unsigned long) args->local_vec_addr; 531 532 if (args->nr_local == 0) 533 return -EINVAL; 534 535 iov->iov = kcalloc(args->nr_local, 536 sizeof(struct rds_iovec), 537 GFP_KERNEL); 538 if (!iov->iov) 539 return -ENOMEM; 540 541 vec = &iov->iov[0]; 542 543 if (copy_from_user(vec, local_vec, args->nr_local * 544 sizeof(struct rds_iovec))) 545 return -EFAULT; 546 iov->len = args->nr_local; 547 548 /* figure out the number of pages in the vector */ 549 for (i = 0; i < args->nr_local; i++, vec++) { 550 551 nr_pages = rds_pages_in_vec(vec); 552 if (nr_pages == 0) 553 return -EINVAL; 554 555 tot_pages += nr_pages; 556 557 /* 558 * nr_pages for one entry is limited to (UINT_MAX>>PAGE_SHIFT)+1, 559 * so tot_pages cannot overflow without first going negative. 560 */ 561 if (tot_pages < 0) 562 return -EINVAL; 563 } 564 565 return tot_pages * sizeof(struct scatterlist); 566 } 567 568 /* 569 * The application asks for a RDMA transfer. 570 * Extract all arguments and set up the rdma_op 571 */ 572 int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm, 573 struct cmsghdr *cmsg, 574 struct rds_iov_vector *vec) 575 { 576 struct rds_rdma_args *args; 577 struct rm_rdma_op *op = &rm->rdma; 578 int nr_pages; 579 unsigned int nr_bytes; 580 struct page **pages = NULL; 581 struct rds_iovec *iovs; 582 unsigned int i, j; 583 int ret = 0; 584 585 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_rdma_args)) 586 || rm->rdma.op_active) 587 return -EINVAL; 588 589 args = CMSG_DATA(cmsg); 590 591 if (ipv6_addr_any(&rs->rs_bound_addr)) { 592 ret = -ENOTCONN; /* XXX not a great errno */ 593 goto out_ret; 594 } 595 596 if (args->nr_local > UIO_MAXIOV) { 597 ret = -EMSGSIZE; 598 goto out_ret; 599 } 600 601 if (vec->len != args->nr_local) { 602 ret = -EINVAL; 603 goto out_ret; 604 } 605 606 iovs = vec->iov; 607 608 nr_pages = rds_rdma_pages(iovs, args->nr_local); 609 if (nr_pages < 0) { 610 ret = -EINVAL; 611 goto out_ret; 612 } 613 614 pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL); 615 if (!pages) { 616 ret = -ENOMEM; 617 goto out_ret; 618 } 619 620 op->op_write = !!(args->flags & RDS_RDMA_READWRITE); 621 op->op_fence = !!(args->flags & RDS_RDMA_FENCE); 622 op->op_notify = !!(args->flags & RDS_RDMA_NOTIFY_ME); 623 op->op_silent = !!(args->flags & RDS_RDMA_SILENT); 624 op->op_active = 1; 625 op->op_recverr = rs->rs_recverr; 626 WARN_ON(!nr_pages); 627 op->op_sg = rds_message_alloc_sgs(rm, nr_pages, &ret); 628 if (!op->op_sg) 629 goto out_pages; 630 631 if (op->op_notify || op->op_recverr) { 632 /* We allocate an uninitialized notifier here, because 633 * we don't want to do that in the completion handler. We 634 * would have to use GFP_ATOMIC there, and don't want to deal 635 * with failed allocations. 636 */ 637 op->op_notifier = kmalloc(sizeof(struct rds_notifier), GFP_KERNEL); 638 if (!op->op_notifier) { 639 ret = -ENOMEM; 640 goto out_pages; 641 } 642 op->op_notifier->n_user_token = args->user_token; 643 op->op_notifier->n_status = RDS_RDMA_SUCCESS; 644 645 /* Enable rmda notification on data operation for composite 646 * rds messages and make sure notification is enabled only 647 * for the data operation which follows it so that application 648 * gets notified only after full message gets delivered. 649 */ 650 if (rm->data.op_sg) { 651 rm->rdma.op_notify = 0; 652 rm->data.op_notify = !!(args->flags & RDS_RDMA_NOTIFY_ME); 653 } 654 } 655 656 /* The cookie contains the R_Key of the remote memory region, and 657 * optionally an offset into it. This is how we implement RDMA into 658 * unaligned memory. 659 * When setting up the RDMA, we need to add that offset to the 660 * destination address (which is really an offset into the MR) 661 * FIXME: We may want to move this into ib_rdma.c 662 */ 663 op->op_rkey = rds_rdma_cookie_key(args->cookie); 664 op->op_remote_addr = args->remote_vec.addr + rds_rdma_cookie_offset(args->cookie); 665 666 nr_bytes = 0; 667 668 rdsdebug("RDS: rdma prepare nr_local %llu rva %llx rkey %x\n", 669 (unsigned long long)args->nr_local, 670 (unsigned long long)args->remote_vec.addr, 671 op->op_rkey); 672 673 for (i = 0; i < args->nr_local; i++) { 674 struct rds_iovec *iov = &iovs[i]; 675 /* don't need to check, rds_rdma_pages() verified nr will be +nonzero */ 676 unsigned int nr = rds_pages_in_vec(iov); 677 678 rs->rs_user_addr = iov->addr; 679 rs->rs_user_bytes = iov->bytes; 680 681 /* If it's a WRITE operation, we want to pin the pages for reading. 682 * If it's a READ operation, we need to pin the pages for writing. 683 */ 684 ret = rds_pin_pages(iov->addr, nr, pages, !op->op_write); 685 if (ret < 0) 686 goto out_pages; 687 else 688 ret = 0; 689 690 rdsdebug("RDS: nr_bytes %u nr %u iov->bytes %llu iov->addr %llx\n", 691 nr_bytes, nr, iov->bytes, iov->addr); 692 693 nr_bytes += iov->bytes; 694 695 for (j = 0; j < nr; j++) { 696 unsigned int offset = iov->addr & ~PAGE_MASK; 697 struct scatterlist *sg; 698 699 sg = &op->op_sg[op->op_nents + j]; 700 sg_set_page(sg, pages[j], 701 min_t(unsigned int, iov->bytes, PAGE_SIZE - offset), 702 offset); 703 704 rdsdebug("RDS: sg->offset %x sg->len %x iov->addr %llx iov->bytes %llu\n", 705 sg->offset, sg->length, iov->addr, iov->bytes); 706 707 iov->addr += sg->length; 708 iov->bytes -= sg->length; 709 } 710 711 op->op_nents += nr; 712 } 713 714 if (nr_bytes > args->remote_vec.bytes) { 715 rdsdebug("RDS nr_bytes %u remote_bytes %u do not match\n", 716 nr_bytes, 717 (unsigned int) args->remote_vec.bytes); 718 ret = -EINVAL; 719 goto out_pages; 720 } 721 op->op_bytes = nr_bytes; 722 723 out_pages: 724 kfree(pages); 725 out_ret: 726 if (ret) 727 rds_rdma_free_op(op); 728 else 729 rds_stats_inc(s_send_rdma); 730 731 return ret; 732 } 733 734 /* 735 * The application wants us to pass an RDMA destination (aka MR) 736 * to the remote 737 */ 738 int rds_cmsg_rdma_dest(struct rds_sock *rs, struct rds_message *rm, 739 struct cmsghdr *cmsg) 740 { 741 unsigned long flags; 742 struct rds_mr *mr; 743 u32 r_key; 744 int err = 0; 745 746 if (cmsg->cmsg_len < CMSG_LEN(sizeof(rds_rdma_cookie_t)) || 747 rm->m_rdma_cookie != 0) 748 return -EINVAL; 749 750 memcpy(&rm->m_rdma_cookie, CMSG_DATA(cmsg), sizeof(rm->m_rdma_cookie)); 751 752 /* We are reusing a previously mapped MR here. Most likely, the 753 * application has written to the buffer, so we need to explicitly 754 * flush those writes to RAM. Otherwise the HCA may not see them 755 * when doing a DMA from that buffer. 756 */ 757 r_key = rds_rdma_cookie_key(rm->m_rdma_cookie); 758 759 spin_lock_irqsave(&rs->rs_rdma_lock, flags); 760 mr = rds_mr_tree_walk(&rs->rs_rdma_keys, r_key, NULL); 761 if (!mr) 762 err = -EINVAL; /* invalid r_key */ 763 else 764 refcount_inc(&mr->r_refcount); 765 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags); 766 767 if (mr) { 768 mr->r_trans->sync_mr(mr->r_trans_private, DMA_TO_DEVICE); 769 rm->rdma.op_rdma_mr = mr; 770 } 771 return err; 772 } 773 774 /* 775 * The application passes us an address range it wants to enable RDMA 776 * to/from. We map the area, and save the <R_Key,offset> pair 777 * in rm->m_rdma_cookie. This causes it to be sent along to the peer 778 * in an extension header. 779 */ 780 int rds_cmsg_rdma_map(struct rds_sock *rs, struct rds_message *rm, 781 struct cmsghdr *cmsg) 782 { 783 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_get_mr_args)) || 784 rm->m_rdma_cookie != 0) 785 return -EINVAL; 786 787 return __rds_rdma_map(rs, CMSG_DATA(cmsg), &rm->m_rdma_cookie, 788 &rm->rdma.op_rdma_mr, rm->m_conn_path); 789 } 790 791 /* 792 * Fill in rds_message for an atomic request. 793 */ 794 int rds_cmsg_atomic(struct rds_sock *rs, struct rds_message *rm, 795 struct cmsghdr *cmsg) 796 { 797 struct page *page = NULL; 798 struct rds_atomic_args *args; 799 int ret = 0; 800 801 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_atomic_args)) 802 || rm->atomic.op_active) 803 return -EINVAL; 804 805 args = CMSG_DATA(cmsg); 806 807 /* Nonmasked & masked cmsg ops converted to masked hw ops */ 808 switch (cmsg->cmsg_type) { 809 case RDS_CMSG_ATOMIC_FADD: 810 rm->atomic.op_type = RDS_ATOMIC_TYPE_FADD; 811 rm->atomic.op_m_fadd.add = args->fadd.add; 812 rm->atomic.op_m_fadd.nocarry_mask = 0; 813 break; 814 case RDS_CMSG_MASKED_ATOMIC_FADD: 815 rm->atomic.op_type = RDS_ATOMIC_TYPE_FADD; 816 rm->atomic.op_m_fadd.add = args->m_fadd.add; 817 rm->atomic.op_m_fadd.nocarry_mask = args->m_fadd.nocarry_mask; 818 break; 819 case RDS_CMSG_ATOMIC_CSWP: 820 rm->atomic.op_type = RDS_ATOMIC_TYPE_CSWP; 821 rm->atomic.op_m_cswp.compare = args->cswp.compare; 822 rm->atomic.op_m_cswp.swap = args->cswp.swap; 823 rm->atomic.op_m_cswp.compare_mask = ~0; 824 rm->atomic.op_m_cswp.swap_mask = ~0; 825 break; 826 case RDS_CMSG_MASKED_ATOMIC_CSWP: 827 rm->atomic.op_type = RDS_ATOMIC_TYPE_CSWP; 828 rm->atomic.op_m_cswp.compare = args->m_cswp.compare; 829 rm->atomic.op_m_cswp.swap = args->m_cswp.swap; 830 rm->atomic.op_m_cswp.compare_mask = args->m_cswp.compare_mask; 831 rm->atomic.op_m_cswp.swap_mask = args->m_cswp.swap_mask; 832 break; 833 default: 834 BUG(); /* should never happen */ 835 } 836 837 rm->atomic.op_notify = !!(args->flags & RDS_RDMA_NOTIFY_ME); 838 rm->atomic.op_silent = !!(args->flags & RDS_RDMA_SILENT); 839 rm->atomic.op_active = 1; 840 rm->atomic.op_recverr = rs->rs_recverr; 841 rm->atomic.op_sg = rds_message_alloc_sgs(rm, 1, &ret); 842 if (!rm->atomic.op_sg) 843 goto err; 844 845 /* verify 8 byte-aligned */ 846 if (args->local_addr & 0x7) { 847 ret = -EFAULT; 848 goto err; 849 } 850 851 ret = rds_pin_pages(args->local_addr, 1, &page, 1); 852 if (ret != 1) 853 goto err; 854 ret = 0; 855 856 sg_set_page(rm->atomic.op_sg, page, 8, offset_in_page(args->local_addr)); 857 858 if (rm->atomic.op_notify || rm->atomic.op_recverr) { 859 /* We allocate an uninitialized notifier here, because 860 * we don't want to do that in the completion handler. We 861 * would have to use GFP_ATOMIC there, and don't want to deal 862 * with failed allocations. 863 */ 864 rm->atomic.op_notifier = kmalloc(sizeof(*rm->atomic.op_notifier), GFP_KERNEL); 865 if (!rm->atomic.op_notifier) { 866 ret = -ENOMEM; 867 goto err; 868 } 869 870 rm->atomic.op_notifier->n_user_token = args->user_token; 871 rm->atomic.op_notifier->n_status = RDS_RDMA_SUCCESS; 872 } 873 874 rm->atomic.op_rkey = rds_rdma_cookie_key(args->cookie); 875 rm->atomic.op_remote_addr = args->remote_addr + rds_rdma_cookie_offset(args->cookie); 876 877 return ret; 878 err: 879 if (page) 880 put_page(page); 881 rm->atomic.op_active = 0; 882 kfree(rm->atomic.op_notifier); 883 884 return ret; 885 } 886