1 /* 2 * Copyright (c) 2014 Mellanox Technologies. 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/types.h> 34 #include <linux/sched.h> 35 #include <linux/sched/mm.h> 36 #include <linux/sched/task.h> 37 #include <linux/pid.h> 38 #include <linux/slab.h> 39 #include <linux/export.h> 40 #include <linux/vmalloc.h> 41 #include <linux/hugetlb.h> 42 #include <linux/interval_tree.h> 43 #include <linux/pagemap.h> 44 45 #include <rdma/ib_verbs.h> 46 #include <rdma/ib_umem.h> 47 #include <rdma/ib_umem_odp.h> 48 49 #include "uverbs.h" 50 51 static void ib_umem_notifier_start_account(struct ib_umem_odp *umem_odp) 52 { 53 mutex_lock(&umem_odp->umem_mutex); 54 if (umem_odp->notifiers_count++ == 0) 55 /* 56 * Initialize the completion object for waiting on 57 * notifiers. Since notifier_count is zero, no one should be 58 * waiting right now. 59 */ 60 reinit_completion(&umem_odp->notifier_completion); 61 mutex_unlock(&umem_odp->umem_mutex); 62 } 63 64 static void ib_umem_notifier_end_account(struct ib_umem_odp *umem_odp) 65 { 66 mutex_lock(&umem_odp->umem_mutex); 67 /* 68 * This sequence increase will notify the QP page fault that the page 69 * that is going to be mapped in the spte could have been freed. 70 */ 71 ++umem_odp->notifiers_seq; 72 if (--umem_odp->notifiers_count == 0) 73 complete_all(&umem_odp->notifier_completion); 74 mutex_unlock(&umem_odp->umem_mutex); 75 } 76 77 static void ib_umem_notifier_release(struct mmu_notifier *mn, 78 struct mm_struct *mm) 79 { 80 struct ib_ucontext_per_mm *per_mm = 81 container_of(mn, struct ib_ucontext_per_mm, mn); 82 struct rb_node *node; 83 84 down_read(&per_mm->umem_rwsem); 85 if (!per_mm->mn.users) 86 goto out; 87 88 for (node = rb_first_cached(&per_mm->umem_tree); node; 89 node = rb_next(node)) { 90 struct ib_umem_odp *umem_odp = 91 rb_entry(node, struct ib_umem_odp, interval_tree.rb); 92 93 /* 94 * Increase the number of notifiers running, to prevent any 95 * further fault handling on this MR. 96 */ 97 ib_umem_notifier_start_account(umem_odp); 98 complete_all(&umem_odp->notifier_completion); 99 umem_odp->umem.ibdev->ops.invalidate_range( 100 umem_odp, ib_umem_start(umem_odp), 101 ib_umem_end(umem_odp)); 102 } 103 104 out: 105 up_read(&per_mm->umem_rwsem); 106 } 107 108 static int invalidate_range_start_trampoline(struct ib_umem_odp *item, 109 u64 start, u64 end, void *cookie) 110 { 111 ib_umem_notifier_start_account(item); 112 item->umem.ibdev->ops.invalidate_range(item, start, end); 113 return 0; 114 } 115 116 static int ib_umem_notifier_invalidate_range_start(struct mmu_notifier *mn, 117 const struct mmu_notifier_range *range) 118 { 119 struct ib_ucontext_per_mm *per_mm = 120 container_of(mn, struct ib_ucontext_per_mm, mn); 121 int rc; 122 123 if (mmu_notifier_range_blockable(range)) 124 down_read(&per_mm->umem_rwsem); 125 else if (!down_read_trylock(&per_mm->umem_rwsem)) 126 return -EAGAIN; 127 128 if (!per_mm->mn.users) { 129 up_read(&per_mm->umem_rwsem); 130 /* 131 * At this point users is permanently zero and visible to this 132 * CPU without a lock, that fact is relied on to skip the unlock 133 * in range_end. 134 */ 135 return 0; 136 } 137 138 rc = rbt_ib_umem_for_each_in_range(&per_mm->umem_tree, range->start, 139 range->end, 140 invalidate_range_start_trampoline, 141 mmu_notifier_range_blockable(range), 142 NULL); 143 if (rc) 144 up_read(&per_mm->umem_rwsem); 145 return rc; 146 } 147 148 static int invalidate_range_end_trampoline(struct ib_umem_odp *item, u64 start, 149 u64 end, void *cookie) 150 { 151 ib_umem_notifier_end_account(item); 152 return 0; 153 } 154 155 static void ib_umem_notifier_invalidate_range_end(struct mmu_notifier *mn, 156 const struct mmu_notifier_range *range) 157 { 158 struct ib_ucontext_per_mm *per_mm = 159 container_of(mn, struct ib_ucontext_per_mm, mn); 160 161 if (unlikely(!per_mm->mn.users)) 162 return; 163 164 rbt_ib_umem_for_each_in_range(&per_mm->umem_tree, range->start, 165 range->end, 166 invalidate_range_end_trampoline, true, NULL); 167 up_read(&per_mm->umem_rwsem); 168 } 169 170 static struct mmu_notifier *ib_umem_alloc_notifier(struct mm_struct *mm) 171 { 172 struct ib_ucontext_per_mm *per_mm; 173 174 per_mm = kzalloc(sizeof(*per_mm), GFP_KERNEL); 175 if (!per_mm) 176 return ERR_PTR(-ENOMEM); 177 178 per_mm->umem_tree = RB_ROOT_CACHED; 179 init_rwsem(&per_mm->umem_rwsem); 180 181 WARN_ON(mm != current->mm); 182 rcu_read_lock(); 183 per_mm->tgid = get_task_pid(current->group_leader, PIDTYPE_PID); 184 rcu_read_unlock(); 185 return &per_mm->mn; 186 } 187 188 static void ib_umem_free_notifier(struct mmu_notifier *mn) 189 { 190 struct ib_ucontext_per_mm *per_mm = 191 container_of(mn, struct ib_ucontext_per_mm, mn); 192 193 WARN_ON(!RB_EMPTY_ROOT(&per_mm->umem_tree.rb_root)); 194 195 put_pid(per_mm->tgid); 196 kfree(per_mm); 197 } 198 199 static const struct mmu_notifier_ops ib_umem_notifiers = { 200 .release = ib_umem_notifier_release, 201 .invalidate_range_start = ib_umem_notifier_invalidate_range_start, 202 .invalidate_range_end = ib_umem_notifier_invalidate_range_end, 203 .alloc_notifier = ib_umem_alloc_notifier, 204 .free_notifier = ib_umem_free_notifier, 205 }; 206 207 static inline int ib_init_umem_odp(struct ib_umem_odp *umem_odp) 208 { 209 struct ib_ucontext_per_mm *per_mm; 210 struct mmu_notifier *mn; 211 int ret; 212 213 umem_odp->umem.is_odp = 1; 214 if (!umem_odp->is_implicit_odp) { 215 size_t page_size = 1UL << umem_odp->page_shift; 216 size_t pages; 217 218 umem_odp->interval_tree.start = 219 ALIGN_DOWN(umem_odp->umem.address, page_size); 220 if (check_add_overflow(umem_odp->umem.address, 221 (unsigned long)umem_odp->umem.length, 222 &umem_odp->interval_tree.last)) 223 return -EOVERFLOW; 224 umem_odp->interval_tree.last = 225 ALIGN(umem_odp->interval_tree.last, page_size); 226 if (unlikely(umem_odp->interval_tree.last < page_size)) 227 return -EOVERFLOW; 228 229 pages = (umem_odp->interval_tree.last - 230 umem_odp->interval_tree.start) >> 231 umem_odp->page_shift; 232 if (!pages) 233 return -EINVAL; 234 235 /* 236 * Note that the representation of the intervals in the 237 * interval tree considers the ending point as contained in 238 * the interval. 239 */ 240 umem_odp->interval_tree.last--; 241 242 umem_odp->page_list = kvcalloc( 243 pages, sizeof(*umem_odp->page_list), GFP_KERNEL); 244 if (!umem_odp->page_list) 245 return -ENOMEM; 246 247 umem_odp->dma_list = kvcalloc( 248 pages, sizeof(*umem_odp->dma_list), GFP_KERNEL); 249 if (!umem_odp->dma_list) { 250 ret = -ENOMEM; 251 goto out_page_list; 252 } 253 } 254 255 mn = mmu_notifier_get(&ib_umem_notifiers, umem_odp->umem.owning_mm); 256 if (IS_ERR(mn)) { 257 ret = PTR_ERR(mn); 258 goto out_dma_list; 259 } 260 umem_odp->per_mm = per_mm = 261 container_of(mn, struct ib_ucontext_per_mm, mn); 262 263 mutex_init(&umem_odp->umem_mutex); 264 init_completion(&umem_odp->notifier_completion); 265 266 if (!umem_odp->is_implicit_odp) { 267 down_write(&per_mm->umem_rwsem); 268 interval_tree_insert(&umem_odp->interval_tree, 269 &per_mm->umem_tree); 270 up_write(&per_mm->umem_rwsem); 271 } 272 mmgrab(umem_odp->umem.owning_mm); 273 274 return 0; 275 276 out_dma_list: 277 kvfree(umem_odp->dma_list); 278 out_page_list: 279 kvfree(umem_odp->page_list); 280 return ret; 281 } 282 283 /** 284 * ib_umem_odp_alloc_implicit - Allocate a parent implicit ODP umem 285 * 286 * Implicit ODP umems do not have a VA range and do not have any page lists. 287 * They exist only to hold the per_mm reference to help the driver create 288 * children umems. 289 * 290 * @udata: udata from the syscall being used to create the umem 291 * @access: ib_reg_mr access flags 292 */ 293 struct ib_umem_odp *ib_umem_odp_alloc_implicit(struct ib_udata *udata, 294 int access) 295 { 296 struct ib_ucontext *context = 297 container_of(udata, struct uverbs_attr_bundle, driver_udata) 298 ->context; 299 struct ib_umem *umem; 300 struct ib_umem_odp *umem_odp; 301 int ret; 302 303 if (access & IB_ACCESS_HUGETLB) 304 return ERR_PTR(-EINVAL); 305 306 if (!context) 307 return ERR_PTR(-EIO); 308 if (WARN_ON_ONCE(!context->device->ops.invalidate_range)) 309 return ERR_PTR(-EINVAL); 310 311 umem_odp = kzalloc(sizeof(*umem_odp), GFP_KERNEL); 312 if (!umem_odp) 313 return ERR_PTR(-ENOMEM); 314 umem = &umem_odp->umem; 315 umem->ibdev = context->device; 316 umem->writable = ib_access_writable(access); 317 umem->owning_mm = current->mm; 318 umem_odp->is_implicit_odp = 1; 319 umem_odp->page_shift = PAGE_SHIFT; 320 321 ret = ib_init_umem_odp(umem_odp); 322 if (ret) { 323 kfree(umem_odp); 324 return ERR_PTR(ret); 325 } 326 return umem_odp; 327 } 328 EXPORT_SYMBOL(ib_umem_odp_alloc_implicit); 329 330 /** 331 * ib_umem_odp_alloc_child - Allocate a child ODP umem under an implicit 332 * parent ODP umem 333 * 334 * @root: The parent umem enclosing the child. This must be allocated using 335 * ib_alloc_implicit_odp_umem() 336 * @addr: The starting userspace VA 337 * @size: The length of the userspace VA 338 */ 339 struct ib_umem_odp *ib_umem_odp_alloc_child(struct ib_umem_odp *root, 340 unsigned long addr, size_t size) 341 { 342 /* 343 * Caller must ensure that root cannot be freed during the call to 344 * ib_alloc_odp_umem. 345 */ 346 struct ib_umem_odp *odp_data; 347 struct ib_umem *umem; 348 int ret; 349 350 if (WARN_ON(!root->is_implicit_odp)) 351 return ERR_PTR(-EINVAL); 352 353 odp_data = kzalloc(sizeof(*odp_data), GFP_KERNEL); 354 if (!odp_data) 355 return ERR_PTR(-ENOMEM); 356 umem = &odp_data->umem; 357 umem->ibdev = root->umem.ibdev; 358 umem->length = size; 359 umem->address = addr; 360 umem->writable = root->umem.writable; 361 umem->owning_mm = root->umem.owning_mm; 362 odp_data->page_shift = PAGE_SHIFT; 363 364 ret = ib_init_umem_odp(odp_data); 365 if (ret) { 366 kfree(odp_data); 367 return ERR_PTR(ret); 368 } 369 return odp_data; 370 } 371 EXPORT_SYMBOL(ib_umem_odp_alloc_child); 372 373 /** 374 * ib_umem_odp_get - Create a umem_odp for a userspace va 375 * 376 * @udata: userspace context to pin memory for 377 * @addr: userspace virtual address to start at 378 * @size: length of region to pin 379 * @access: IB_ACCESS_xxx flags for memory being pinned 380 * 381 * The driver should use when the access flags indicate ODP memory. It avoids 382 * pinning, instead, stores the mm for future page fault handling in 383 * conjunction with MMU notifiers. 384 */ 385 struct ib_umem_odp *ib_umem_odp_get(struct ib_udata *udata, unsigned long addr, 386 size_t size, int access) 387 { 388 struct ib_umem_odp *umem_odp; 389 struct ib_ucontext *context; 390 struct mm_struct *mm; 391 int ret; 392 393 if (!udata) 394 return ERR_PTR(-EIO); 395 396 context = container_of(udata, struct uverbs_attr_bundle, driver_udata) 397 ->context; 398 if (!context) 399 return ERR_PTR(-EIO); 400 401 if (WARN_ON_ONCE(!(access & IB_ACCESS_ON_DEMAND)) || 402 WARN_ON_ONCE(!context->device->ops.invalidate_range)) 403 return ERR_PTR(-EINVAL); 404 405 umem_odp = kzalloc(sizeof(struct ib_umem_odp), GFP_KERNEL); 406 if (!umem_odp) 407 return ERR_PTR(-ENOMEM); 408 409 umem_odp->umem.ibdev = context->device; 410 umem_odp->umem.length = size; 411 umem_odp->umem.address = addr; 412 umem_odp->umem.writable = ib_access_writable(access); 413 umem_odp->umem.owning_mm = mm = current->mm; 414 415 umem_odp->page_shift = PAGE_SHIFT; 416 if (access & IB_ACCESS_HUGETLB) { 417 struct vm_area_struct *vma; 418 struct hstate *h; 419 420 down_read(&mm->mmap_sem); 421 vma = find_vma(mm, ib_umem_start(umem_odp)); 422 if (!vma || !is_vm_hugetlb_page(vma)) { 423 up_read(&mm->mmap_sem); 424 ret = -EINVAL; 425 goto err_free; 426 } 427 h = hstate_vma(vma); 428 umem_odp->page_shift = huge_page_shift(h); 429 up_read(&mm->mmap_sem); 430 } 431 432 ret = ib_init_umem_odp(umem_odp); 433 if (ret) 434 goto err_free; 435 return umem_odp; 436 437 err_free: 438 kfree(umem_odp); 439 return ERR_PTR(ret); 440 } 441 EXPORT_SYMBOL(ib_umem_odp_get); 442 443 void ib_umem_odp_release(struct ib_umem_odp *umem_odp) 444 { 445 struct ib_ucontext_per_mm *per_mm = umem_odp->per_mm; 446 447 /* 448 * Ensure that no more pages are mapped in the umem. 449 * 450 * It is the driver's responsibility to ensure, before calling us, 451 * that the hardware will not attempt to access the MR any more. 452 */ 453 if (!umem_odp->is_implicit_odp) { 454 ib_umem_odp_unmap_dma_pages(umem_odp, ib_umem_start(umem_odp), 455 ib_umem_end(umem_odp)); 456 kvfree(umem_odp->dma_list); 457 kvfree(umem_odp->page_list); 458 } 459 460 down_write(&per_mm->umem_rwsem); 461 if (!umem_odp->is_implicit_odp) { 462 interval_tree_remove(&umem_odp->interval_tree, 463 &per_mm->umem_tree); 464 complete_all(&umem_odp->notifier_completion); 465 } 466 /* 467 * NOTE! mmu_notifier_unregister() can happen between a start/end 468 * callback, resulting in a missing end, and thus an unbalanced 469 * lock. This doesn't really matter to us since we are about to kfree 470 * the memory that holds the lock, however LOCKDEP doesn't like this. 471 * Thus we call the mmu_notifier_put under the rwsem and test the 472 * internal users count to reliably see if we are past this point. 473 */ 474 mmu_notifier_put(&per_mm->mn); 475 up_write(&per_mm->umem_rwsem); 476 477 mmdrop(umem_odp->umem.owning_mm); 478 kfree(umem_odp); 479 } 480 EXPORT_SYMBOL(ib_umem_odp_release); 481 482 /* 483 * Map for DMA and insert a single page into the on-demand paging page tables. 484 * 485 * @umem: the umem to insert the page to. 486 * @page_index: index in the umem to add the page to. 487 * @page: the page struct to map and add. 488 * @access_mask: access permissions needed for this page. 489 * @current_seq: sequence number for synchronization with invalidations. 490 * the sequence number is taken from 491 * umem_odp->notifiers_seq. 492 * 493 * The function returns -EFAULT if the DMA mapping operation fails. It returns 494 * -EAGAIN if a concurrent invalidation prevents us from updating the page. 495 * 496 * The page is released via put_user_page even if the operation failed. For 497 * on-demand pinning, the page is released whenever it isn't stored in the 498 * umem. 499 */ 500 static int ib_umem_odp_map_dma_single_page( 501 struct ib_umem_odp *umem_odp, 502 int page_index, 503 struct page *page, 504 u64 access_mask, 505 unsigned long current_seq) 506 { 507 struct ib_device *dev = umem_odp->umem.ibdev; 508 dma_addr_t dma_addr; 509 int remove_existing_mapping = 0; 510 int ret = 0; 511 512 /* 513 * Note: we avoid writing if seq is different from the initial seq, to 514 * handle case of a racing notifier. This check also allows us to bail 515 * early if we have a notifier running in parallel with us. 516 */ 517 if (ib_umem_mmu_notifier_retry(umem_odp, current_seq)) { 518 ret = -EAGAIN; 519 goto out; 520 } 521 if (!(umem_odp->dma_list[page_index])) { 522 dma_addr = 523 ib_dma_map_page(dev, page, 0, BIT(umem_odp->page_shift), 524 DMA_BIDIRECTIONAL); 525 if (ib_dma_mapping_error(dev, dma_addr)) { 526 ret = -EFAULT; 527 goto out; 528 } 529 umem_odp->dma_list[page_index] = dma_addr | access_mask; 530 umem_odp->page_list[page_index] = page; 531 umem_odp->npages++; 532 } else if (umem_odp->page_list[page_index] == page) { 533 umem_odp->dma_list[page_index] |= access_mask; 534 } else { 535 pr_err("error: got different pages in IB device and from get_user_pages. IB device page: %p, gup page: %p\n", 536 umem_odp->page_list[page_index], page); 537 /* Better remove the mapping now, to prevent any further 538 * damage. */ 539 remove_existing_mapping = 1; 540 } 541 542 out: 543 put_user_page(page); 544 545 if (remove_existing_mapping) { 546 ib_umem_notifier_start_account(umem_odp); 547 dev->ops.invalidate_range( 548 umem_odp, 549 ib_umem_start(umem_odp) + 550 (page_index << umem_odp->page_shift), 551 ib_umem_start(umem_odp) + 552 ((page_index + 1) << umem_odp->page_shift)); 553 ib_umem_notifier_end_account(umem_odp); 554 ret = -EAGAIN; 555 } 556 557 return ret; 558 } 559 560 /** 561 * ib_umem_odp_map_dma_pages - Pin and DMA map userspace memory in an ODP MR. 562 * 563 * Pins the range of pages passed in the argument, and maps them to 564 * DMA addresses. The DMA addresses of the mapped pages is updated in 565 * umem_odp->dma_list. 566 * 567 * Returns the number of pages mapped in success, negative error code 568 * for failure. 569 * An -EAGAIN error code is returned when a concurrent mmu notifier prevents 570 * the function from completing its task. 571 * An -ENOENT error code indicates that userspace process is being terminated 572 * and mm was already destroyed. 573 * @umem_odp: the umem to map and pin 574 * @user_virt: the address from which we need to map. 575 * @bcnt: the minimal number of bytes to pin and map. The mapping might be 576 * bigger due to alignment, and may also be smaller in case of an error 577 * pinning or mapping a page. The actual pages mapped is returned in 578 * the return value. 579 * @access_mask: bit mask of the requested access permissions for the given 580 * range. 581 * @current_seq: the MMU notifiers sequance value for synchronization with 582 * invalidations. the sequance number is read from 583 * umem_odp->notifiers_seq before calling this function 584 */ 585 int ib_umem_odp_map_dma_pages(struct ib_umem_odp *umem_odp, u64 user_virt, 586 u64 bcnt, u64 access_mask, 587 unsigned long current_seq) 588 { 589 struct task_struct *owning_process = NULL; 590 struct mm_struct *owning_mm = umem_odp->umem.owning_mm; 591 struct page **local_page_list = NULL; 592 u64 page_mask, off; 593 int j, k, ret = 0, start_idx, npages = 0; 594 unsigned int flags = 0, page_shift; 595 phys_addr_t p = 0; 596 597 if (access_mask == 0) 598 return -EINVAL; 599 600 if (user_virt < ib_umem_start(umem_odp) || 601 user_virt + bcnt > ib_umem_end(umem_odp)) 602 return -EFAULT; 603 604 local_page_list = (struct page **)__get_free_page(GFP_KERNEL); 605 if (!local_page_list) 606 return -ENOMEM; 607 608 page_shift = umem_odp->page_shift; 609 page_mask = ~(BIT(page_shift) - 1); 610 off = user_virt & (~page_mask); 611 user_virt = user_virt & page_mask; 612 bcnt += off; /* Charge for the first page offset as well. */ 613 614 /* 615 * owning_process is allowed to be NULL, this means somehow the mm is 616 * existing beyond the lifetime of the originating process.. Presumably 617 * mmget_not_zero will fail in this case. 618 */ 619 owning_process = get_pid_task(umem_odp->per_mm->tgid, PIDTYPE_PID); 620 if (!owning_process || !mmget_not_zero(owning_mm)) { 621 ret = -EINVAL; 622 goto out_put_task; 623 } 624 625 if (access_mask & ODP_WRITE_ALLOWED_BIT) 626 flags |= FOLL_WRITE; 627 628 start_idx = (user_virt - ib_umem_start(umem_odp)) >> page_shift; 629 k = start_idx; 630 631 while (bcnt > 0) { 632 const size_t gup_num_pages = min_t(size_t, 633 (bcnt + BIT(page_shift) - 1) >> page_shift, 634 PAGE_SIZE / sizeof(struct page *)); 635 636 down_read(&owning_mm->mmap_sem); 637 /* 638 * Note: this might result in redundent page getting. We can 639 * avoid this by checking dma_list to be 0 before calling 640 * get_user_pages. However, this make the code much more 641 * complex (and doesn't gain us much performance in most use 642 * cases). 643 */ 644 npages = get_user_pages_remote(owning_process, owning_mm, 645 user_virt, gup_num_pages, 646 flags, local_page_list, NULL, NULL); 647 up_read(&owning_mm->mmap_sem); 648 649 if (npages < 0) { 650 if (npages != -EAGAIN) 651 pr_warn("fail to get %zu user pages with error %d\n", gup_num_pages, npages); 652 else 653 pr_debug("fail to get %zu user pages with error %d\n", gup_num_pages, npages); 654 break; 655 } 656 657 bcnt -= min_t(size_t, npages << PAGE_SHIFT, bcnt); 658 mutex_lock(&umem_odp->umem_mutex); 659 for (j = 0; j < npages; j++, user_virt += PAGE_SIZE) { 660 if (user_virt & ~page_mask) { 661 p += PAGE_SIZE; 662 if (page_to_phys(local_page_list[j]) != p) { 663 ret = -EFAULT; 664 break; 665 } 666 put_user_page(local_page_list[j]); 667 continue; 668 } 669 670 ret = ib_umem_odp_map_dma_single_page( 671 umem_odp, k, local_page_list[j], 672 access_mask, current_seq); 673 if (ret < 0) { 674 if (ret != -EAGAIN) 675 pr_warn("ib_umem_odp_map_dma_single_page failed with error %d\n", ret); 676 else 677 pr_debug("ib_umem_odp_map_dma_single_page failed with error %d\n", ret); 678 break; 679 } 680 681 p = page_to_phys(local_page_list[j]); 682 k++; 683 } 684 mutex_unlock(&umem_odp->umem_mutex); 685 686 if (ret < 0) { 687 /* 688 * Release pages, remembering that the first page 689 * to hit an error was already released by 690 * ib_umem_odp_map_dma_single_page(). 691 */ 692 if (npages - (j + 1) > 0) 693 put_user_pages(&local_page_list[j+1], 694 npages - (j + 1)); 695 break; 696 } 697 } 698 699 if (ret >= 0) { 700 if (npages < 0 && k == start_idx) 701 ret = npages; 702 else 703 ret = k - start_idx; 704 } 705 706 mmput(owning_mm); 707 out_put_task: 708 if (owning_process) 709 put_task_struct(owning_process); 710 free_page((unsigned long)local_page_list); 711 return ret; 712 } 713 EXPORT_SYMBOL(ib_umem_odp_map_dma_pages); 714 715 void ib_umem_odp_unmap_dma_pages(struct ib_umem_odp *umem_odp, u64 virt, 716 u64 bound) 717 { 718 int idx; 719 u64 addr; 720 struct ib_device *dev = umem_odp->umem.ibdev; 721 722 virt = max_t(u64, virt, ib_umem_start(umem_odp)); 723 bound = min_t(u64, bound, ib_umem_end(umem_odp)); 724 /* Note that during the run of this function, the 725 * notifiers_count of the MR is > 0, preventing any racing 726 * faults from completion. We might be racing with other 727 * invalidations, so we must make sure we free each page only 728 * once. */ 729 mutex_lock(&umem_odp->umem_mutex); 730 for (addr = virt; addr < bound; addr += BIT(umem_odp->page_shift)) { 731 idx = (addr - ib_umem_start(umem_odp)) >> umem_odp->page_shift; 732 if (umem_odp->page_list[idx]) { 733 struct page *page = umem_odp->page_list[idx]; 734 dma_addr_t dma = umem_odp->dma_list[idx]; 735 dma_addr_t dma_addr = dma & ODP_DMA_ADDR_MASK; 736 737 WARN_ON(!dma_addr); 738 739 ib_dma_unmap_page(dev, dma_addr, 740 BIT(umem_odp->page_shift), 741 DMA_BIDIRECTIONAL); 742 if (dma & ODP_WRITE_ALLOWED_BIT) { 743 struct page *head_page = compound_head(page); 744 /* 745 * set_page_dirty prefers being called with 746 * the page lock. However, MMU notifiers are 747 * called sometimes with and sometimes without 748 * the lock. We rely on the umem_mutex instead 749 * to prevent other mmu notifiers from 750 * continuing and allowing the page mapping to 751 * be removed. 752 */ 753 set_page_dirty(head_page); 754 } 755 umem_odp->page_list[idx] = NULL; 756 umem_odp->dma_list[idx] = 0; 757 umem_odp->npages--; 758 } 759 } 760 mutex_unlock(&umem_odp->umem_mutex); 761 } 762 EXPORT_SYMBOL(ib_umem_odp_unmap_dma_pages); 763 764 /* @last is not a part of the interval. See comment for function 765 * node_last. 766 */ 767 int rbt_ib_umem_for_each_in_range(struct rb_root_cached *root, 768 u64 start, u64 last, 769 umem_call_back cb, 770 bool blockable, 771 void *cookie) 772 { 773 int ret_val = 0; 774 struct interval_tree_node *node, *next; 775 struct ib_umem_odp *umem; 776 777 if (unlikely(start == last)) 778 return ret_val; 779 780 for (node = interval_tree_iter_first(root, start, last - 1); 781 node; node = next) { 782 /* TODO move the blockable decision up to the callback */ 783 if (!blockable) 784 return -EAGAIN; 785 next = interval_tree_iter_next(node, start, last - 1); 786 umem = container_of(node, struct ib_umem_odp, interval_tree); 787 ret_val = cb(umem, start, last, cookie) || ret_val; 788 } 789 790 return ret_val; 791 } 792