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