1 /* 2 * Copyright (c) 2006 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/kernel.h> 34 #include <linux/slab.h> 35 #include <linux/rculist.h> 36 37 #include "rds.h" 38 #include "ib.h" 39 #include "xlist.h" 40 41 static struct workqueue_struct *rds_ib_fmr_wq; 42 43 static DEFINE_PER_CPU(unsigned long, clean_list_grace); 44 #define CLEAN_LIST_BUSY_BIT 0 45 46 /* 47 * This is stored as mr->r_trans_private. 48 */ 49 struct rds_ib_mr { 50 struct rds_ib_device *device; 51 struct rds_ib_mr_pool *pool; 52 struct ib_fmr *fmr; 53 54 struct xlist_head xlist; 55 56 /* unmap_list is for freeing */ 57 struct list_head unmap_list; 58 unsigned int remap_count; 59 60 struct scatterlist *sg; 61 unsigned int sg_len; 62 u64 *dma; 63 int sg_dma_len; 64 }; 65 66 /* 67 * Our own little FMR pool 68 */ 69 struct rds_ib_mr_pool { 70 struct mutex flush_lock; /* serialize fmr invalidate */ 71 struct delayed_work flush_worker; /* flush worker */ 72 73 atomic_t item_count; /* total # of MRs */ 74 atomic_t dirty_count; /* # dirty of MRs */ 75 76 struct xlist_head drop_list; /* MRs that have reached their max_maps limit */ 77 struct xlist_head free_list; /* unused MRs */ 78 struct xlist_head clean_list; /* global unused & unamapped MRs */ 79 wait_queue_head_t flush_wait; 80 81 atomic_t free_pinned; /* memory pinned by free MRs */ 82 unsigned long max_items; 83 unsigned long max_items_soft; 84 unsigned long max_free_pinned; 85 struct ib_fmr_attr fmr_attr; 86 }; 87 88 static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool, int free_all, struct rds_ib_mr **); 89 static void rds_ib_teardown_mr(struct rds_ib_mr *ibmr); 90 static void rds_ib_mr_pool_flush_worker(struct work_struct *work); 91 92 static struct rds_ib_device *rds_ib_get_device(__be32 ipaddr) 93 { 94 struct rds_ib_device *rds_ibdev; 95 struct rds_ib_ipaddr *i_ipaddr; 96 97 rcu_read_lock(); 98 list_for_each_entry_rcu(rds_ibdev, &rds_ib_devices, list) { 99 list_for_each_entry_rcu(i_ipaddr, &rds_ibdev->ipaddr_list, list) { 100 if (i_ipaddr->ipaddr == ipaddr) { 101 atomic_inc(&rds_ibdev->refcount); 102 rcu_read_unlock(); 103 return rds_ibdev; 104 } 105 } 106 } 107 rcu_read_unlock(); 108 109 return NULL; 110 } 111 112 static int rds_ib_add_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr) 113 { 114 struct rds_ib_ipaddr *i_ipaddr; 115 116 i_ipaddr = kmalloc(sizeof *i_ipaddr, GFP_KERNEL); 117 if (!i_ipaddr) 118 return -ENOMEM; 119 120 i_ipaddr->ipaddr = ipaddr; 121 122 spin_lock_irq(&rds_ibdev->spinlock); 123 list_add_tail_rcu(&i_ipaddr->list, &rds_ibdev->ipaddr_list); 124 spin_unlock_irq(&rds_ibdev->spinlock); 125 126 return 0; 127 } 128 129 static void rds_ib_remove_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr) 130 { 131 struct rds_ib_ipaddr *i_ipaddr; 132 struct rds_ib_ipaddr *to_free = NULL; 133 134 135 spin_lock_irq(&rds_ibdev->spinlock); 136 list_for_each_entry_rcu(i_ipaddr, &rds_ibdev->ipaddr_list, list) { 137 if (i_ipaddr->ipaddr == ipaddr) { 138 list_del_rcu(&i_ipaddr->list); 139 to_free = i_ipaddr; 140 break; 141 } 142 } 143 spin_unlock_irq(&rds_ibdev->spinlock); 144 145 if (to_free) { 146 synchronize_rcu(); 147 kfree(to_free); 148 } 149 } 150 151 int rds_ib_update_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr) 152 { 153 struct rds_ib_device *rds_ibdev_old; 154 155 rds_ibdev_old = rds_ib_get_device(ipaddr); 156 if (rds_ibdev_old) { 157 rds_ib_remove_ipaddr(rds_ibdev_old, ipaddr); 158 rds_ib_dev_put(rds_ibdev_old); 159 } 160 161 return rds_ib_add_ipaddr(rds_ibdev, ipaddr); 162 } 163 164 void rds_ib_add_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn) 165 { 166 struct rds_ib_connection *ic = conn->c_transport_data; 167 168 /* conn was previously on the nodev_conns_list */ 169 spin_lock_irq(&ib_nodev_conns_lock); 170 BUG_ON(list_empty(&ib_nodev_conns)); 171 BUG_ON(list_empty(&ic->ib_node)); 172 list_del(&ic->ib_node); 173 174 spin_lock(&rds_ibdev->spinlock); 175 list_add_tail(&ic->ib_node, &rds_ibdev->conn_list); 176 spin_unlock(&rds_ibdev->spinlock); 177 spin_unlock_irq(&ib_nodev_conns_lock); 178 179 ic->rds_ibdev = rds_ibdev; 180 atomic_inc(&rds_ibdev->refcount); 181 } 182 183 void rds_ib_remove_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn) 184 { 185 struct rds_ib_connection *ic = conn->c_transport_data; 186 187 /* place conn on nodev_conns_list */ 188 spin_lock(&ib_nodev_conns_lock); 189 190 spin_lock_irq(&rds_ibdev->spinlock); 191 BUG_ON(list_empty(&ic->ib_node)); 192 list_del(&ic->ib_node); 193 spin_unlock_irq(&rds_ibdev->spinlock); 194 195 list_add_tail(&ic->ib_node, &ib_nodev_conns); 196 197 spin_unlock(&ib_nodev_conns_lock); 198 199 ic->rds_ibdev = NULL; 200 rds_ib_dev_put(rds_ibdev); 201 } 202 203 void rds_ib_destroy_nodev_conns(void) 204 { 205 struct rds_ib_connection *ic, *_ic; 206 LIST_HEAD(tmp_list); 207 208 /* avoid calling conn_destroy with irqs off */ 209 spin_lock_irq(&ib_nodev_conns_lock); 210 list_splice(&ib_nodev_conns, &tmp_list); 211 spin_unlock_irq(&ib_nodev_conns_lock); 212 213 list_for_each_entry_safe(ic, _ic, &tmp_list, ib_node) 214 rds_conn_destroy(ic->conn); 215 } 216 217 struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_ibdev) 218 { 219 struct rds_ib_mr_pool *pool; 220 221 pool = kzalloc(sizeof(*pool), GFP_KERNEL); 222 if (!pool) 223 return ERR_PTR(-ENOMEM); 224 225 INIT_XLIST_HEAD(&pool->free_list); 226 INIT_XLIST_HEAD(&pool->drop_list); 227 INIT_XLIST_HEAD(&pool->clean_list); 228 mutex_init(&pool->flush_lock); 229 init_waitqueue_head(&pool->flush_wait); 230 INIT_DELAYED_WORK(&pool->flush_worker, rds_ib_mr_pool_flush_worker); 231 232 pool->fmr_attr.max_pages = fmr_message_size; 233 pool->fmr_attr.max_maps = rds_ibdev->fmr_max_remaps; 234 pool->fmr_attr.page_shift = PAGE_SHIFT; 235 pool->max_free_pinned = rds_ibdev->max_fmrs * fmr_message_size / 4; 236 237 /* We never allow more than max_items MRs to be allocated. 238 * When we exceed more than max_items_soft, we start freeing 239 * items more aggressively. 240 * Make sure that max_items > max_items_soft > max_items / 2 241 */ 242 pool->max_items_soft = rds_ibdev->max_fmrs * 3 / 4; 243 pool->max_items = rds_ibdev->max_fmrs; 244 245 return pool; 246 } 247 248 void rds_ib_get_mr_info(struct rds_ib_device *rds_ibdev, struct rds_info_rdma_connection *iinfo) 249 { 250 struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; 251 252 iinfo->rdma_mr_max = pool->max_items; 253 iinfo->rdma_mr_size = pool->fmr_attr.max_pages; 254 } 255 256 void rds_ib_destroy_mr_pool(struct rds_ib_mr_pool *pool) 257 { 258 cancel_delayed_work_sync(&pool->flush_worker); 259 rds_ib_flush_mr_pool(pool, 1, NULL); 260 WARN_ON(atomic_read(&pool->item_count)); 261 WARN_ON(atomic_read(&pool->free_pinned)); 262 kfree(pool); 263 } 264 265 static void refill_local(struct rds_ib_mr_pool *pool, struct xlist_head *xl, 266 struct rds_ib_mr **ibmr_ret) 267 { 268 struct xlist_head *ibmr_xl; 269 ibmr_xl = xlist_del_head_fast(xl); 270 *ibmr_ret = list_entry(ibmr_xl, struct rds_ib_mr, xlist); 271 } 272 273 static inline struct rds_ib_mr *rds_ib_reuse_fmr(struct rds_ib_mr_pool *pool) 274 { 275 struct rds_ib_mr *ibmr = NULL; 276 struct xlist_head *ret; 277 unsigned long *flag; 278 279 preempt_disable(); 280 flag = &__get_cpu_var(clean_list_grace); 281 set_bit(CLEAN_LIST_BUSY_BIT, flag); 282 ret = xlist_del_head(&pool->clean_list); 283 if (ret) 284 ibmr = list_entry(ret, struct rds_ib_mr, xlist); 285 286 clear_bit(CLEAN_LIST_BUSY_BIT, flag); 287 preempt_enable(); 288 return ibmr; 289 } 290 291 static inline void wait_clean_list_grace(void) 292 { 293 int cpu; 294 unsigned long *flag; 295 296 for_each_online_cpu(cpu) { 297 flag = &per_cpu(clean_list_grace, cpu); 298 while (test_bit(CLEAN_LIST_BUSY_BIT, flag)) 299 cpu_relax(); 300 } 301 } 302 303 static struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev) 304 { 305 struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; 306 struct rds_ib_mr *ibmr = NULL; 307 int err = 0, iter = 0; 308 309 if (atomic_read(&pool->dirty_count) >= pool->max_items / 10) 310 queue_delayed_work(rds_ib_fmr_wq, &pool->flush_worker, 10); 311 312 while (1) { 313 ibmr = rds_ib_reuse_fmr(pool); 314 if (ibmr) 315 return ibmr; 316 317 /* No clean MRs - now we have the choice of either 318 * allocating a fresh MR up to the limit imposed by the 319 * driver, or flush any dirty unused MRs. 320 * We try to avoid stalling in the send path if possible, 321 * so we allocate as long as we're allowed to. 322 * 323 * We're fussy with enforcing the FMR limit, though. If the driver 324 * tells us we can't use more than N fmrs, we shouldn't start 325 * arguing with it */ 326 if (atomic_inc_return(&pool->item_count) <= pool->max_items) 327 break; 328 329 atomic_dec(&pool->item_count); 330 331 if (++iter > 2) { 332 rds_ib_stats_inc(s_ib_rdma_mr_pool_depleted); 333 return ERR_PTR(-EAGAIN); 334 } 335 336 /* We do have some empty MRs. Flush them out. */ 337 rds_ib_stats_inc(s_ib_rdma_mr_pool_wait); 338 rds_ib_flush_mr_pool(pool, 0, &ibmr); 339 if (ibmr) 340 return ibmr; 341 } 342 343 ibmr = kzalloc_node(sizeof(*ibmr), GFP_KERNEL, rdsibdev_to_node(rds_ibdev)); 344 if (!ibmr) { 345 err = -ENOMEM; 346 goto out_no_cigar; 347 } 348 349 memset(ibmr, 0, sizeof(*ibmr)); 350 351 ibmr->fmr = ib_alloc_fmr(rds_ibdev->pd, 352 (IB_ACCESS_LOCAL_WRITE | 353 IB_ACCESS_REMOTE_READ | 354 IB_ACCESS_REMOTE_WRITE| 355 IB_ACCESS_REMOTE_ATOMIC), 356 &pool->fmr_attr); 357 if (IS_ERR(ibmr->fmr)) { 358 err = PTR_ERR(ibmr->fmr); 359 ibmr->fmr = NULL; 360 printk(KERN_WARNING "RDS/IB: ib_alloc_fmr failed (err=%d)\n", err); 361 goto out_no_cigar; 362 } 363 364 rds_ib_stats_inc(s_ib_rdma_mr_alloc); 365 return ibmr; 366 367 out_no_cigar: 368 if (ibmr) { 369 if (ibmr->fmr) 370 ib_dealloc_fmr(ibmr->fmr); 371 kfree(ibmr); 372 } 373 atomic_dec(&pool->item_count); 374 return ERR_PTR(err); 375 } 376 377 static int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev, struct rds_ib_mr *ibmr, 378 struct scatterlist *sg, unsigned int nents) 379 { 380 struct ib_device *dev = rds_ibdev->dev; 381 struct scatterlist *scat = sg; 382 u64 io_addr = 0; 383 u64 *dma_pages; 384 u32 len; 385 int page_cnt, sg_dma_len; 386 int i, j; 387 int ret; 388 389 sg_dma_len = ib_dma_map_sg(dev, sg, nents, 390 DMA_BIDIRECTIONAL); 391 if (unlikely(!sg_dma_len)) { 392 printk(KERN_WARNING "RDS/IB: dma_map_sg failed!\n"); 393 return -EBUSY; 394 } 395 396 len = 0; 397 page_cnt = 0; 398 399 for (i = 0; i < sg_dma_len; ++i) { 400 unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]); 401 u64 dma_addr = ib_sg_dma_address(dev, &scat[i]); 402 403 if (dma_addr & ~PAGE_MASK) { 404 if (i > 0) 405 return -EINVAL; 406 else 407 ++page_cnt; 408 } 409 if ((dma_addr + dma_len) & ~PAGE_MASK) { 410 if (i < sg_dma_len - 1) 411 return -EINVAL; 412 else 413 ++page_cnt; 414 } 415 416 len += dma_len; 417 } 418 419 page_cnt += len >> PAGE_SHIFT; 420 if (page_cnt > fmr_message_size) 421 return -EINVAL; 422 423 dma_pages = kmalloc_node(sizeof(u64) * page_cnt, GFP_ATOMIC, 424 rdsibdev_to_node(rds_ibdev)); 425 if (!dma_pages) 426 return -ENOMEM; 427 428 page_cnt = 0; 429 for (i = 0; i < sg_dma_len; ++i) { 430 unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]); 431 u64 dma_addr = ib_sg_dma_address(dev, &scat[i]); 432 433 for (j = 0; j < dma_len; j += PAGE_SIZE) 434 dma_pages[page_cnt++] = 435 (dma_addr & PAGE_MASK) + j; 436 } 437 438 ret = ib_map_phys_fmr(ibmr->fmr, 439 dma_pages, page_cnt, io_addr); 440 if (ret) 441 goto out; 442 443 /* Success - we successfully remapped the MR, so we can 444 * safely tear down the old mapping. */ 445 rds_ib_teardown_mr(ibmr); 446 447 ibmr->sg = scat; 448 ibmr->sg_len = nents; 449 ibmr->sg_dma_len = sg_dma_len; 450 ibmr->remap_count++; 451 452 rds_ib_stats_inc(s_ib_rdma_mr_used); 453 ret = 0; 454 455 out: 456 kfree(dma_pages); 457 458 return ret; 459 } 460 461 void rds_ib_sync_mr(void *trans_private, int direction) 462 { 463 struct rds_ib_mr *ibmr = trans_private; 464 struct rds_ib_device *rds_ibdev = ibmr->device; 465 466 switch (direction) { 467 case DMA_FROM_DEVICE: 468 ib_dma_sync_sg_for_cpu(rds_ibdev->dev, ibmr->sg, 469 ibmr->sg_dma_len, DMA_BIDIRECTIONAL); 470 break; 471 case DMA_TO_DEVICE: 472 ib_dma_sync_sg_for_device(rds_ibdev->dev, ibmr->sg, 473 ibmr->sg_dma_len, DMA_BIDIRECTIONAL); 474 break; 475 } 476 } 477 478 static void __rds_ib_teardown_mr(struct rds_ib_mr *ibmr) 479 { 480 struct rds_ib_device *rds_ibdev = ibmr->device; 481 482 if (ibmr->sg_dma_len) { 483 ib_dma_unmap_sg(rds_ibdev->dev, 484 ibmr->sg, ibmr->sg_len, 485 DMA_BIDIRECTIONAL); 486 ibmr->sg_dma_len = 0; 487 } 488 489 /* Release the s/g list */ 490 if (ibmr->sg_len) { 491 unsigned int i; 492 493 for (i = 0; i < ibmr->sg_len; ++i) { 494 struct page *page = sg_page(&ibmr->sg[i]); 495 496 /* FIXME we need a way to tell a r/w MR 497 * from a r/o MR */ 498 BUG_ON(irqs_disabled()); 499 set_page_dirty(page); 500 put_page(page); 501 } 502 kfree(ibmr->sg); 503 504 ibmr->sg = NULL; 505 ibmr->sg_len = 0; 506 } 507 } 508 509 static void rds_ib_teardown_mr(struct rds_ib_mr *ibmr) 510 { 511 unsigned int pinned = ibmr->sg_len; 512 513 __rds_ib_teardown_mr(ibmr); 514 if (pinned) { 515 struct rds_ib_device *rds_ibdev = ibmr->device; 516 struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; 517 518 atomic_sub(pinned, &pool->free_pinned); 519 } 520 } 521 522 static inline unsigned int rds_ib_flush_goal(struct rds_ib_mr_pool *pool, int free_all) 523 { 524 unsigned int item_count; 525 526 item_count = atomic_read(&pool->item_count); 527 if (free_all) 528 return item_count; 529 530 return 0; 531 } 532 533 /* 534 * given an xlist of mrs, put them all into the list_head for more processing 535 */ 536 static void xlist_append_to_list(struct xlist_head *xlist, struct list_head *list) 537 { 538 struct rds_ib_mr *ibmr; 539 struct xlist_head splice; 540 struct xlist_head *cur; 541 struct xlist_head *next; 542 543 splice.next = NULL; 544 xlist_splice(xlist, &splice); 545 cur = splice.next; 546 while (cur) { 547 next = cur->next; 548 ibmr = list_entry(cur, struct rds_ib_mr, xlist); 549 list_add_tail(&ibmr->unmap_list, list); 550 cur = next; 551 } 552 } 553 554 /* 555 * this takes a list head of mrs and turns it into an xlist of clusters. 556 * each cluster has an xlist of MR_CLUSTER_SIZE mrs that are ready for 557 * reuse. 558 */ 559 static void list_append_to_xlist(struct rds_ib_mr_pool *pool, 560 struct list_head *list, struct xlist_head *xlist, 561 struct xlist_head **tail_ret) 562 { 563 struct rds_ib_mr *ibmr; 564 struct xlist_head *cur_mr = xlist; 565 struct xlist_head *tail_mr = NULL; 566 567 list_for_each_entry(ibmr, list, unmap_list) { 568 tail_mr = &ibmr->xlist; 569 tail_mr->next = NULL; 570 cur_mr->next = tail_mr; 571 cur_mr = tail_mr; 572 } 573 *tail_ret = tail_mr; 574 } 575 576 /* 577 * Flush our pool of MRs. 578 * At a minimum, all currently unused MRs are unmapped. 579 * If the number of MRs allocated exceeds the limit, we also try 580 * to free as many MRs as needed to get back to this limit. 581 */ 582 static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool, 583 int free_all, struct rds_ib_mr **ibmr_ret) 584 { 585 struct rds_ib_mr *ibmr, *next; 586 struct xlist_head clean_xlist; 587 struct xlist_head *clean_tail; 588 LIST_HEAD(unmap_list); 589 LIST_HEAD(fmr_list); 590 unsigned long unpinned = 0; 591 unsigned int nfreed = 0, ncleaned = 0, free_goal; 592 int ret = 0; 593 594 rds_ib_stats_inc(s_ib_rdma_mr_pool_flush); 595 596 if (ibmr_ret) { 597 DEFINE_WAIT(wait); 598 while(!mutex_trylock(&pool->flush_lock)) { 599 ibmr = rds_ib_reuse_fmr(pool); 600 if (ibmr) { 601 *ibmr_ret = ibmr; 602 finish_wait(&pool->flush_wait, &wait); 603 goto out_nolock; 604 } 605 606 prepare_to_wait(&pool->flush_wait, &wait, 607 TASK_UNINTERRUPTIBLE); 608 if (xlist_empty(&pool->clean_list)) 609 schedule(); 610 611 ibmr = rds_ib_reuse_fmr(pool); 612 if (ibmr) { 613 *ibmr_ret = ibmr; 614 finish_wait(&pool->flush_wait, &wait); 615 goto out_nolock; 616 } 617 } 618 finish_wait(&pool->flush_wait, &wait); 619 } else 620 mutex_lock(&pool->flush_lock); 621 622 if (ibmr_ret) { 623 ibmr = rds_ib_reuse_fmr(pool); 624 if (ibmr) { 625 *ibmr_ret = ibmr; 626 goto out; 627 } 628 } 629 630 /* Get the list of all MRs to be dropped. Ordering matters - 631 * we want to put drop_list ahead of free_list. 632 */ 633 xlist_append_to_list(&pool->drop_list, &unmap_list); 634 xlist_append_to_list(&pool->free_list, &unmap_list); 635 if (free_all) 636 xlist_append_to_list(&pool->clean_list, &unmap_list); 637 638 free_goal = rds_ib_flush_goal(pool, free_all); 639 640 if (list_empty(&unmap_list)) 641 goto out; 642 643 /* String all ib_mr's onto one list and hand them to ib_unmap_fmr */ 644 list_for_each_entry(ibmr, &unmap_list, unmap_list) 645 list_add(&ibmr->fmr->list, &fmr_list); 646 647 ret = ib_unmap_fmr(&fmr_list); 648 if (ret) 649 printk(KERN_WARNING "RDS/IB: ib_unmap_fmr failed (err=%d)\n", ret); 650 651 /* Now we can destroy the DMA mapping and unpin any pages */ 652 list_for_each_entry_safe(ibmr, next, &unmap_list, unmap_list) { 653 unpinned += ibmr->sg_len; 654 __rds_ib_teardown_mr(ibmr); 655 if (nfreed < free_goal || ibmr->remap_count >= pool->fmr_attr.max_maps) { 656 rds_ib_stats_inc(s_ib_rdma_mr_free); 657 list_del(&ibmr->unmap_list); 658 ib_dealloc_fmr(ibmr->fmr); 659 kfree(ibmr); 660 nfreed++; 661 } 662 ncleaned++; 663 } 664 665 if (!list_empty(&unmap_list)) { 666 /* we have to make sure that none of the things we're about 667 * to put on the clean list would race with other cpus trying 668 * to pull items off. The xlist would explode if we managed to 669 * remove something from the clean list and then add it back again 670 * while another CPU was spinning on that same item in xlist_del_head. 671 * 672 * This is pretty unlikely, but just in case wait for an xlist grace period 673 * here before adding anything back into the clean list. 674 */ 675 wait_clean_list_grace(); 676 677 list_append_to_xlist(pool, &unmap_list, &clean_xlist, &clean_tail); 678 if (ibmr_ret) 679 refill_local(pool, &clean_xlist, ibmr_ret); 680 681 /* refill_local may have emptied our list */ 682 if (!xlist_empty(&clean_xlist)) 683 xlist_add(clean_xlist.next, clean_tail, &pool->clean_list); 684 685 } 686 687 atomic_sub(unpinned, &pool->free_pinned); 688 atomic_sub(ncleaned, &pool->dirty_count); 689 atomic_sub(nfreed, &pool->item_count); 690 691 out: 692 mutex_unlock(&pool->flush_lock); 693 if (waitqueue_active(&pool->flush_wait)) 694 wake_up(&pool->flush_wait); 695 out_nolock: 696 return ret; 697 } 698 699 int rds_ib_fmr_init(void) 700 { 701 rds_ib_fmr_wq = create_workqueue("rds_fmr_flushd"); 702 if (!rds_ib_fmr_wq) 703 return -ENOMEM; 704 return 0; 705 } 706 707 /* 708 * By the time this is called all the IB devices should have been torn down and 709 * had their pools freed. As each pool is freed its work struct is waited on, 710 * so the pool flushing work queue should be idle by the time we get here. 711 */ 712 void rds_ib_fmr_exit(void) 713 { 714 destroy_workqueue(rds_ib_fmr_wq); 715 } 716 717 static void rds_ib_mr_pool_flush_worker(struct work_struct *work) 718 { 719 struct rds_ib_mr_pool *pool = container_of(work, struct rds_ib_mr_pool, flush_worker.work); 720 721 rds_ib_flush_mr_pool(pool, 0, NULL); 722 } 723 724 void rds_ib_free_mr(void *trans_private, int invalidate) 725 { 726 struct rds_ib_mr *ibmr = trans_private; 727 struct rds_ib_device *rds_ibdev = ibmr->device; 728 struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; 729 730 rdsdebug("RDS/IB: free_mr nents %u\n", ibmr->sg_len); 731 732 /* Return it to the pool's free list */ 733 if (ibmr->remap_count >= pool->fmr_attr.max_maps) 734 xlist_add(&ibmr->xlist, &ibmr->xlist, &pool->drop_list); 735 else 736 xlist_add(&ibmr->xlist, &ibmr->xlist, &pool->free_list); 737 738 atomic_add(ibmr->sg_len, &pool->free_pinned); 739 atomic_inc(&pool->dirty_count); 740 741 /* If we've pinned too many pages, request a flush */ 742 if (atomic_read(&pool->free_pinned) >= pool->max_free_pinned || 743 atomic_read(&pool->dirty_count) >= pool->max_items / 10) 744 queue_delayed_work(rds_ib_fmr_wq, &pool->flush_worker, 10); 745 746 if (invalidate) { 747 if (likely(!in_interrupt())) { 748 rds_ib_flush_mr_pool(pool, 0, NULL); 749 } else { 750 /* We get here if the user created a MR marked 751 * as use_once and invalidate at the same time. */ 752 queue_delayed_work(rds_ib_fmr_wq, 753 &pool->flush_worker, 10); 754 } 755 } 756 757 rds_ib_dev_put(rds_ibdev); 758 } 759 760 void rds_ib_flush_mrs(void) 761 { 762 struct rds_ib_device *rds_ibdev; 763 764 down_read(&rds_ib_devices_lock); 765 list_for_each_entry(rds_ibdev, &rds_ib_devices, list) { 766 struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; 767 768 if (pool) 769 rds_ib_flush_mr_pool(pool, 0, NULL); 770 } 771 up_read(&rds_ib_devices_lock); 772 } 773 774 void *rds_ib_get_mr(struct scatterlist *sg, unsigned long nents, 775 struct rds_sock *rs, u32 *key_ret) 776 { 777 struct rds_ib_device *rds_ibdev; 778 struct rds_ib_mr *ibmr = NULL; 779 int ret; 780 781 rds_ibdev = rds_ib_get_device(rs->rs_bound_addr); 782 if (!rds_ibdev) { 783 ret = -ENODEV; 784 goto out; 785 } 786 787 if (!rds_ibdev->mr_pool) { 788 ret = -ENODEV; 789 goto out; 790 } 791 792 ibmr = rds_ib_alloc_fmr(rds_ibdev); 793 if (IS_ERR(ibmr)) 794 return ibmr; 795 796 ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents); 797 if (ret == 0) 798 *key_ret = ibmr->fmr->rkey; 799 else 800 printk(KERN_WARNING "RDS/IB: map_fmr failed (errno=%d)\n", ret); 801 802 ibmr->device = rds_ibdev; 803 rds_ibdev = NULL; 804 805 out: 806 if (ret) { 807 if (ibmr) 808 rds_ib_free_mr(ibmr, 0); 809 ibmr = ERR_PTR(ret); 810 } 811 if (rds_ibdev) 812 rds_ib_dev_put(rds_ibdev); 813 return ibmr; 814 } 815 816