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 35 #include "rds.h" 36 #include "rdma.h" 37 #include "ib.h" 38 39 40 /* 41 * This is stored as mr->r_trans_private. 42 */ 43 struct rds_ib_mr { 44 struct rds_ib_device *device; 45 struct rds_ib_mr_pool *pool; 46 struct ib_fmr *fmr; 47 struct list_head list; 48 unsigned int remap_count; 49 50 struct scatterlist *sg; 51 unsigned int sg_len; 52 u64 *dma; 53 int sg_dma_len; 54 }; 55 56 /* 57 * Our own little FMR pool 58 */ 59 struct rds_ib_mr_pool { 60 struct mutex flush_lock; /* serialize fmr invalidate */ 61 struct work_struct flush_worker; /* flush worker */ 62 63 spinlock_t list_lock; /* protect variables below */ 64 atomic_t item_count; /* total # of MRs */ 65 atomic_t dirty_count; /* # dirty of MRs */ 66 struct list_head drop_list; /* MRs that have reached their max_maps limit */ 67 struct list_head free_list; /* unused MRs */ 68 struct list_head clean_list; /* unused & unamapped MRs */ 69 atomic_t free_pinned; /* memory pinned by free MRs */ 70 unsigned long max_items; 71 unsigned long max_items_soft; 72 unsigned long max_free_pinned; 73 struct ib_fmr_attr fmr_attr; 74 }; 75 76 static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool, int free_all); 77 static void rds_ib_teardown_mr(struct rds_ib_mr *ibmr); 78 static void rds_ib_mr_pool_flush_worker(struct work_struct *work); 79 80 static struct rds_ib_device *rds_ib_get_device(__be32 ipaddr) 81 { 82 struct rds_ib_device *rds_ibdev; 83 struct rds_ib_ipaddr *i_ipaddr; 84 85 list_for_each_entry(rds_ibdev, &rds_ib_devices, list) { 86 spin_lock_irq(&rds_ibdev->spinlock); 87 list_for_each_entry(i_ipaddr, &rds_ibdev->ipaddr_list, list) { 88 if (i_ipaddr->ipaddr == ipaddr) { 89 spin_unlock_irq(&rds_ibdev->spinlock); 90 return rds_ibdev; 91 } 92 } 93 spin_unlock_irq(&rds_ibdev->spinlock); 94 } 95 96 return NULL; 97 } 98 99 static int rds_ib_add_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr) 100 { 101 struct rds_ib_ipaddr *i_ipaddr; 102 103 i_ipaddr = kmalloc(sizeof *i_ipaddr, GFP_KERNEL); 104 if (!i_ipaddr) 105 return -ENOMEM; 106 107 i_ipaddr->ipaddr = ipaddr; 108 109 spin_lock_irq(&rds_ibdev->spinlock); 110 list_add_tail(&i_ipaddr->list, &rds_ibdev->ipaddr_list); 111 spin_unlock_irq(&rds_ibdev->spinlock); 112 113 return 0; 114 } 115 116 static void rds_ib_remove_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr) 117 { 118 struct rds_ib_ipaddr *i_ipaddr, *next; 119 120 spin_lock_irq(&rds_ibdev->spinlock); 121 list_for_each_entry_safe(i_ipaddr, next, &rds_ibdev->ipaddr_list, list) { 122 if (i_ipaddr->ipaddr == ipaddr) { 123 list_del(&i_ipaddr->list); 124 kfree(i_ipaddr); 125 break; 126 } 127 } 128 spin_unlock_irq(&rds_ibdev->spinlock); 129 } 130 131 int rds_ib_update_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr) 132 { 133 struct rds_ib_device *rds_ibdev_old; 134 135 rds_ibdev_old = rds_ib_get_device(ipaddr); 136 if (rds_ibdev_old) 137 rds_ib_remove_ipaddr(rds_ibdev_old, ipaddr); 138 139 return rds_ib_add_ipaddr(rds_ibdev, ipaddr); 140 } 141 142 void rds_ib_add_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn) 143 { 144 struct rds_ib_connection *ic = conn->c_transport_data; 145 146 /* conn was previously on the nodev_conns_list */ 147 spin_lock_irq(&ib_nodev_conns_lock); 148 BUG_ON(list_empty(&ib_nodev_conns)); 149 BUG_ON(list_empty(&ic->ib_node)); 150 list_del(&ic->ib_node); 151 152 spin_lock_irq(&rds_ibdev->spinlock); 153 list_add_tail(&ic->ib_node, &rds_ibdev->conn_list); 154 spin_unlock_irq(&rds_ibdev->spinlock); 155 spin_unlock_irq(&ib_nodev_conns_lock); 156 157 ic->rds_ibdev = rds_ibdev; 158 } 159 160 void rds_ib_remove_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn) 161 { 162 struct rds_ib_connection *ic = conn->c_transport_data; 163 164 /* place conn on nodev_conns_list */ 165 spin_lock(&ib_nodev_conns_lock); 166 167 spin_lock_irq(&rds_ibdev->spinlock); 168 BUG_ON(list_empty(&ic->ib_node)); 169 list_del(&ic->ib_node); 170 spin_unlock_irq(&rds_ibdev->spinlock); 171 172 list_add_tail(&ic->ib_node, &ib_nodev_conns); 173 174 spin_unlock(&ib_nodev_conns_lock); 175 176 ic->rds_ibdev = NULL; 177 } 178 179 void __rds_ib_destroy_conns(struct list_head *list, spinlock_t *list_lock) 180 { 181 struct rds_ib_connection *ic, *_ic; 182 LIST_HEAD(tmp_list); 183 184 /* avoid calling conn_destroy with irqs off */ 185 spin_lock_irq(list_lock); 186 list_splice(list, &tmp_list); 187 INIT_LIST_HEAD(list); 188 spin_unlock_irq(list_lock); 189 190 list_for_each_entry_safe(ic, _ic, &tmp_list, ib_node) 191 rds_conn_destroy(ic->conn); 192 } 193 194 struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_ibdev) 195 { 196 struct rds_ib_mr_pool *pool; 197 198 pool = kzalloc(sizeof(*pool), GFP_KERNEL); 199 if (!pool) 200 return ERR_PTR(-ENOMEM); 201 202 INIT_LIST_HEAD(&pool->free_list); 203 INIT_LIST_HEAD(&pool->drop_list); 204 INIT_LIST_HEAD(&pool->clean_list); 205 mutex_init(&pool->flush_lock); 206 spin_lock_init(&pool->list_lock); 207 INIT_WORK(&pool->flush_worker, rds_ib_mr_pool_flush_worker); 208 209 pool->fmr_attr.max_pages = fmr_message_size; 210 pool->fmr_attr.max_maps = rds_ibdev->fmr_max_remaps; 211 pool->fmr_attr.page_shift = PAGE_SHIFT; 212 pool->max_free_pinned = rds_ibdev->max_fmrs * fmr_message_size / 4; 213 214 /* We never allow more than max_items MRs to be allocated. 215 * When we exceed more than max_items_soft, we start freeing 216 * items more aggressively. 217 * Make sure that max_items > max_items_soft > max_items / 2 218 */ 219 pool->max_items_soft = rds_ibdev->max_fmrs * 3 / 4; 220 pool->max_items = rds_ibdev->max_fmrs; 221 222 return pool; 223 } 224 225 void rds_ib_get_mr_info(struct rds_ib_device *rds_ibdev, struct rds_info_rdma_connection *iinfo) 226 { 227 struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; 228 229 iinfo->rdma_mr_max = pool->max_items; 230 iinfo->rdma_mr_size = pool->fmr_attr.max_pages; 231 } 232 233 void rds_ib_destroy_mr_pool(struct rds_ib_mr_pool *pool) 234 { 235 flush_workqueue(rds_wq); 236 rds_ib_flush_mr_pool(pool, 1); 237 BUG_ON(atomic_read(&pool->item_count)); 238 BUG_ON(atomic_read(&pool->free_pinned)); 239 kfree(pool); 240 } 241 242 static inline struct rds_ib_mr *rds_ib_reuse_fmr(struct rds_ib_mr_pool *pool) 243 { 244 struct rds_ib_mr *ibmr = NULL; 245 unsigned long flags; 246 247 spin_lock_irqsave(&pool->list_lock, flags); 248 if (!list_empty(&pool->clean_list)) { 249 ibmr = list_entry(pool->clean_list.next, struct rds_ib_mr, list); 250 list_del_init(&ibmr->list); 251 } 252 spin_unlock_irqrestore(&pool->list_lock, flags); 253 254 return ibmr; 255 } 256 257 static struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev) 258 { 259 struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; 260 struct rds_ib_mr *ibmr = NULL; 261 int err = 0, iter = 0; 262 263 while (1) { 264 ibmr = rds_ib_reuse_fmr(pool); 265 if (ibmr) 266 return ibmr; 267 268 /* No clean MRs - now we have the choice of either 269 * allocating a fresh MR up to the limit imposed by the 270 * driver, or flush any dirty unused MRs. 271 * We try to avoid stalling in the send path if possible, 272 * so we allocate as long as we're allowed to. 273 * 274 * We're fussy with enforcing the FMR limit, though. If the driver 275 * tells us we can't use more than N fmrs, we shouldn't start 276 * arguing with it */ 277 if (atomic_inc_return(&pool->item_count) <= pool->max_items) 278 break; 279 280 atomic_dec(&pool->item_count); 281 282 if (++iter > 2) { 283 rds_ib_stats_inc(s_ib_rdma_mr_pool_depleted); 284 return ERR_PTR(-EAGAIN); 285 } 286 287 /* We do have some empty MRs. Flush them out. */ 288 rds_ib_stats_inc(s_ib_rdma_mr_pool_wait); 289 rds_ib_flush_mr_pool(pool, 0); 290 } 291 292 ibmr = kzalloc(sizeof(*ibmr), GFP_KERNEL); 293 if (!ibmr) { 294 err = -ENOMEM; 295 goto out_no_cigar; 296 } 297 298 ibmr->fmr = ib_alloc_fmr(rds_ibdev->pd, 299 (IB_ACCESS_LOCAL_WRITE | 300 IB_ACCESS_REMOTE_READ | 301 IB_ACCESS_REMOTE_WRITE), 302 &pool->fmr_attr); 303 if (IS_ERR(ibmr->fmr)) { 304 err = PTR_ERR(ibmr->fmr); 305 ibmr->fmr = NULL; 306 printk(KERN_WARNING "RDS/IB: ib_alloc_fmr failed (err=%d)\n", err); 307 goto out_no_cigar; 308 } 309 310 rds_ib_stats_inc(s_ib_rdma_mr_alloc); 311 return ibmr; 312 313 out_no_cigar: 314 if (ibmr) { 315 if (ibmr->fmr) 316 ib_dealloc_fmr(ibmr->fmr); 317 kfree(ibmr); 318 } 319 atomic_dec(&pool->item_count); 320 return ERR_PTR(err); 321 } 322 323 static int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev, struct rds_ib_mr *ibmr, 324 struct scatterlist *sg, unsigned int nents) 325 { 326 struct ib_device *dev = rds_ibdev->dev; 327 struct scatterlist *scat = sg; 328 u64 io_addr = 0; 329 u64 *dma_pages; 330 u32 len; 331 int page_cnt, sg_dma_len; 332 int i, j; 333 int ret; 334 335 sg_dma_len = ib_dma_map_sg(dev, sg, nents, 336 DMA_BIDIRECTIONAL); 337 if (unlikely(!sg_dma_len)) { 338 printk(KERN_WARNING "RDS/IB: dma_map_sg failed!\n"); 339 return -EBUSY; 340 } 341 342 len = 0; 343 page_cnt = 0; 344 345 for (i = 0; i < sg_dma_len; ++i) { 346 unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]); 347 u64 dma_addr = ib_sg_dma_address(dev, &scat[i]); 348 349 if (dma_addr & ~PAGE_MASK) { 350 if (i > 0) 351 return -EINVAL; 352 else 353 ++page_cnt; 354 } 355 if ((dma_addr + dma_len) & ~PAGE_MASK) { 356 if (i < sg_dma_len - 1) 357 return -EINVAL; 358 else 359 ++page_cnt; 360 } 361 362 len += dma_len; 363 } 364 365 page_cnt += len >> PAGE_SHIFT; 366 if (page_cnt > fmr_message_size) 367 return -EINVAL; 368 369 dma_pages = kmalloc(sizeof(u64) * page_cnt, GFP_ATOMIC); 370 if (!dma_pages) 371 return -ENOMEM; 372 373 page_cnt = 0; 374 for (i = 0; i < sg_dma_len; ++i) { 375 unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]); 376 u64 dma_addr = ib_sg_dma_address(dev, &scat[i]); 377 378 for (j = 0; j < dma_len; j += PAGE_SIZE) 379 dma_pages[page_cnt++] = 380 (dma_addr & PAGE_MASK) + j; 381 } 382 383 ret = ib_map_phys_fmr(ibmr->fmr, 384 dma_pages, page_cnt, io_addr); 385 if (ret) 386 goto out; 387 388 /* Success - we successfully remapped the MR, so we can 389 * safely tear down the old mapping. */ 390 rds_ib_teardown_mr(ibmr); 391 392 ibmr->sg = scat; 393 ibmr->sg_len = nents; 394 ibmr->sg_dma_len = sg_dma_len; 395 ibmr->remap_count++; 396 397 rds_ib_stats_inc(s_ib_rdma_mr_used); 398 ret = 0; 399 400 out: 401 kfree(dma_pages); 402 403 return ret; 404 } 405 406 void rds_ib_sync_mr(void *trans_private, int direction) 407 { 408 struct rds_ib_mr *ibmr = trans_private; 409 struct rds_ib_device *rds_ibdev = ibmr->device; 410 411 switch (direction) { 412 case DMA_FROM_DEVICE: 413 ib_dma_sync_sg_for_cpu(rds_ibdev->dev, ibmr->sg, 414 ibmr->sg_dma_len, DMA_BIDIRECTIONAL); 415 break; 416 case DMA_TO_DEVICE: 417 ib_dma_sync_sg_for_device(rds_ibdev->dev, ibmr->sg, 418 ibmr->sg_dma_len, DMA_BIDIRECTIONAL); 419 break; 420 } 421 } 422 423 static void __rds_ib_teardown_mr(struct rds_ib_mr *ibmr) 424 { 425 struct rds_ib_device *rds_ibdev = ibmr->device; 426 427 if (ibmr->sg_dma_len) { 428 ib_dma_unmap_sg(rds_ibdev->dev, 429 ibmr->sg, ibmr->sg_len, 430 DMA_BIDIRECTIONAL); 431 ibmr->sg_dma_len = 0; 432 } 433 434 /* Release the s/g list */ 435 if (ibmr->sg_len) { 436 unsigned int i; 437 438 for (i = 0; i < ibmr->sg_len; ++i) { 439 struct page *page = sg_page(&ibmr->sg[i]); 440 441 /* FIXME we need a way to tell a r/w MR 442 * from a r/o MR */ 443 set_page_dirty(page); 444 put_page(page); 445 } 446 kfree(ibmr->sg); 447 448 ibmr->sg = NULL; 449 ibmr->sg_len = 0; 450 } 451 } 452 453 static void rds_ib_teardown_mr(struct rds_ib_mr *ibmr) 454 { 455 unsigned int pinned = ibmr->sg_len; 456 457 __rds_ib_teardown_mr(ibmr); 458 if (pinned) { 459 struct rds_ib_device *rds_ibdev = ibmr->device; 460 struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; 461 462 atomic_sub(pinned, &pool->free_pinned); 463 } 464 } 465 466 static inline unsigned int rds_ib_flush_goal(struct rds_ib_mr_pool *pool, int free_all) 467 { 468 unsigned int item_count; 469 470 item_count = atomic_read(&pool->item_count); 471 if (free_all) 472 return item_count; 473 474 return 0; 475 } 476 477 /* 478 * Flush our pool of MRs. 479 * At a minimum, all currently unused MRs are unmapped. 480 * If the number of MRs allocated exceeds the limit, we also try 481 * to free as many MRs as needed to get back to this limit. 482 */ 483 static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool, int free_all) 484 { 485 struct rds_ib_mr *ibmr, *next; 486 LIST_HEAD(unmap_list); 487 LIST_HEAD(fmr_list); 488 unsigned long unpinned = 0; 489 unsigned long flags; 490 unsigned int nfreed = 0, ncleaned = 0, free_goal; 491 int ret = 0; 492 493 rds_ib_stats_inc(s_ib_rdma_mr_pool_flush); 494 495 mutex_lock(&pool->flush_lock); 496 497 spin_lock_irqsave(&pool->list_lock, flags); 498 /* Get the list of all MRs to be dropped. Ordering matters - 499 * we want to put drop_list ahead of free_list. */ 500 list_splice_init(&pool->free_list, &unmap_list); 501 list_splice_init(&pool->drop_list, &unmap_list); 502 if (free_all) 503 list_splice_init(&pool->clean_list, &unmap_list); 504 spin_unlock_irqrestore(&pool->list_lock, flags); 505 506 free_goal = rds_ib_flush_goal(pool, free_all); 507 508 if (list_empty(&unmap_list)) 509 goto out; 510 511 /* String all ib_mr's onto one list and hand them to ib_unmap_fmr */ 512 list_for_each_entry(ibmr, &unmap_list, list) 513 list_add(&ibmr->fmr->list, &fmr_list); 514 ret = ib_unmap_fmr(&fmr_list); 515 if (ret) 516 printk(KERN_WARNING "RDS/IB: ib_unmap_fmr failed (err=%d)\n", ret); 517 518 /* Now we can destroy the DMA mapping and unpin any pages */ 519 list_for_each_entry_safe(ibmr, next, &unmap_list, list) { 520 unpinned += ibmr->sg_len; 521 __rds_ib_teardown_mr(ibmr); 522 if (nfreed < free_goal || ibmr->remap_count >= pool->fmr_attr.max_maps) { 523 rds_ib_stats_inc(s_ib_rdma_mr_free); 524 list_del(&ibmr->list); 525 ib_dealloc_fmr(ibmr->fmr); 526 kfree(ibmr); 527 nfreed++; 528 } 529 ncleaned++; 530 } 531 532 spin_lock_irqsave(&pool->list_lock, flags); 533 list_splice(&unmap_list, &pool->clean_list); 534 spin_unlock_irqrestore(&pool->list_lock, flags); 535 536 atomic_sub(unpinned, &pool->free_pinned); 537 atomic_sub(ncleaned, &pool->dirty_count); 538 atomic_sub(nfreed, &pool->item_count); 539 540 out: 541 mutex_unlock(&pool->flush_lock); 542 return ret; 543 } 544 545 static void rds_ib_mr_pool_flush_worker(struct work_struct *work) 546 { 547 struct rds_ib_mr_pool *pool = container_of(work, struct rds_ib_mr_pool, flush_worker); 548 549 rds_ib_flush_mr_pool(pool, 0); 550 } 551 552 void rds_ib_free_mr(void *trans_private, int invalidate) 553 { 554 struct rds_ib_mr *ibmr = trans_private; 555 struct rds_ib_device *rds_ibdev = ibmr->device; 556 struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; 557 unsigned long flags; 558 559 rdsdebug("RDS/IB: free_mr nents %u\n", ibmr->sg_len); 560 561 /* Return it to the pool's free list */ 562 spin_lock_irqsave(&pool->list_lock, flags); 563 if (ibmr->remap_count >= pool->fmr_attr.max_maps) 564 list_add(&ibmr->list, &pool->drop_list); 565 else 566 list_add(&ibmr->list, &pool->free_list); 567 568 atomic_add(ibmr->sg_len, &pool->free_pinned); 569 atomic_inc(&pool->dirty_count); 570 spin_unlock_irqrestore(&pool->list_lock, flags); 571 572 /* If we've pinned too many pages, request a flush */ 573 if (atomic_read(&pool->free_pinned) >= pool->max_free_pinned || 574 atomic_read(&pool->dirty_count) >= pool->max_items / 10) 575 queue_work(rds_wq, &pool->flush_worker); 576 577 if (invalidate) { 578 if (likely(!in_interrupt())) { 579 rds_ib_flush_mr_pool(pool, 0); 580 } else { 581 /* We get here if the user created a MR marked 582 * as use_once and invalidate at the same time. */ 583 queue_work(rds_wq, &pool->flush_worker); 584 } 585 } 586 } 587 588 void rds_ib_flush_mrs(void) 589 { 590 struct rds_ib_device *rds_ibdev; 591 592 list_for_each_entry(rds_ibdev, &rds_ib_devices, list) { 593 struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; 594 595 if (pool) 596 rds_ib_flush_mr_pool(pool, 0); 597 } 598 } 599 600 void *rds_ib_get_mr(struct scatterlist *sg, unsigned long nents, 601 struct rds_sock *rs, u32 *key_ret) 602 { 603 struct rds_ib_device *rds_ibdev; 604 struct rds_ib_mr *ibmr = NULL; 605 int ret; 606 607 rds_ibdev = rds_ib_get_device(rs->rs_bound_addr); 608 if (!rds_ibdev) { 609 ret = -ENODEV; 610 goto out; 611 } 612 613 if (!rds_ibdev->mr_pool) { 614 ret = -ENODEV; 615 goto out; 616 } 617 618 ibmr = rds_ib_alloc_fmr(rds_ibdev); 619 if (IS_ERR(ibmr)) 620 return ibmr; 621 622 ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents); 623 if (ret == 0) 624 *key_ret = ibmr->fmr->rkey; 625 else 626 printk(KERN_WARNING "RDS/IB: map_fmr failed (errno=%d)\n", ret); 627 628 ibmr->device = rds_ibdev; 629 630 out: 631 if (ret) { 632 if (ibmr) 633 rds_ib_free_mr(ibmr, 0); 634 ibmr = ERR_PTR(ret); 635 } 636 return ibmr; 637 } 638