1 /* 2 * Copyright (c) Red Hat Inc. 3 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sub license, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the 12 * next paragraph) shall be included in all copies or substantial portions 13 * of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 21 * DEALINGS IN THE SOFTWARE. 22 * 23 * Authors: Dave Airlie <airlied@redhat.com> 24 * Jerome Glisse <jglisse@redhat.com> 25 * Pauli Nieminen <suokkos@gmail.com> 26 */ 27 /* 28 * Copyright (c) 2013 The FreeBSD Foundation 29 * All rights reserved. 30 * 31 * Portions of this software were developed by Konstantin Belousov 32 * <kib@FreeBSD.org> under sponsorship from the FreeBSD Foundation. 33 */ 34 35 /* simple list based uncached page pool 36 * - Pool collects resently freed pages for reuse 37 * - Use page->lru to keep a free list 38 * - doesn't track currently in use pages 39 */ 40 41 #define pr_fmt(fmt) "[TTM] " fmt 42 43 #include <linux/list.h> 44 #include <linux/spinlock.h> 45 #include <linux/highmem.h> 46 #include <linux/mm_types.h> 47 #include <linux/module.h> 48 #include <linux/mm.h> 49 #include <linux/seq_file.h> /* for seq_printf */ 50 #include <linux/dma-mapping.h> 51 52 #include <linux/atomic.h> 53 54 #include <drm/ttm/ttm_bo_driver.h> 55 #include <drm/ttm/ttm_page_alloc.h> 56 57 #include <sys/eventhandler.h> 58 #include <vm/vm_page2.h> 59 60 #if IS_ENABLED(CONFIG_AGP) 61 #include <asm/agp.h> 62 #endif 63 #ifdef CONFIG_X86 64 #include <asm/set_memory.h> 65 #endif 66 67 #define NUM_PAGES_TO_ALLOC (PAGE_SIZE/sizeof(struct page *)) 68 #define SMALL_ALLOCATION 16 69 #define FREE_ALL_PAGES (~0U) 70 /* times are in msecs */ 71 #define PAGE_FREE_INTERVAL 1000 72 73 /** 74 * struct ttm_page_pool - Pool to reuse recently allocated uc/wc pages. 75 * 76 * @lock: Protects the shared pool from concurrnet access. Must be used with 77 * irqsave/irqrestore variants because pool allocator maybe called from 78 * delayed work. 79 * @fill_lock: Prevent concurrent calls to fill. 80 * @list: Pool of free uc/wc pages for fast reuse. 81 * @gfp_flags: Flags to pass for alloc_page. 82 * @npages: Number of pages in pool. 83 */ 84 struct ttm_page_pool { 85 struct lock lock; 86 bool fill_lock; 87 struct pglist list; 88 gfp_t gfp_flags; 89 unsigned npages; 90 char *name; 91 unsigned long nfrees; 92 unsigned long nrefills; 93 }; 94 95 /** 96 * Limits for the pool. They are handled without locks because only place where 97 * they may change is in sysfs store. They won't have immediate effect anyway 98 * so forcing serialization to access them is pointless. 99 */ 100 101 struct ttm_pool_opts { 102 unsigned alloc_size; 103 unsigned max_size; 104 unsigned small; 105 }; 106 107 #define NUM_POOLS 4 108 109 /** 110 * struct ttm_pool_manager - Holds memory pools for fst allocation 111 * 112 * Manager is read only object for pool code so it doesn't need locking. 113 * 114 * @free_interval: minimum number of jiffies between freeing pages from pool. 115 * @page_alloc_inited: reference counting for pool allocation. 116 * @work: Work that is used to shrink the pool. Work is only run when there is 117 * some pages to free. 118 * @small_allocation: Limit in number of pages what is small allocation. 119 * 120 * @pools: All pool objects in use. 121 **/ 122 struct ttm_pool_manager { 123 struct kobject kobj; 124 struct shrinker mm_shrink; 125 eventhandler_tag lowmem_handler; 126 struct ttm_pool_opts options; 127 128 union { 129 struct ttm_page_pool pools[NUM_POOLS]; 130 struct { 131 struct ttm_page_pool wc_pool; 132 struct ttm_page_pool uc_pool; 133 struct ttm_page_pool wc_pool_dma32; 134 struct ttm_page_pool uc_pool_dma32; 135 } ; 136 }; 137 }; 138 139 static struct attribute ttm_page_pool_max = { 140 .name = "pool_max_size", 141 .mode = S_IRUGO | S_IWUSR 142 }; 143 static struct attribute ttm_page_pool_small = { 144 .name = "pool_small_allocation", 145 .mode = S_IRUGO | S_IWUSR 146 }; 147 static struct attribute ttm_page_pool_alloc_size = { 148 .name = "pool_allocation_size", 149 .mode = S_IRUGO | S_IWUSR 150 }; 151 152 static struct attribute *ttm_pool_attrs[] = { 153 &ttm_page_pool_max, 154 &ttm_page_pool_small, 155 &ttm_page_pool_alloc_size, 156 NULL 157 }; 158 159 static void ttm_pool_kobj_release(struct kobject *kobj) 160 { 161 struct ttm_pool_manager *m = 162 container_of(kobj, struct ttm_pool_manager, kobj); 163 kfree(m); 164 } 165 166 static ssize_t ttm_pool_store(struct kobject *kobj, 167 struct attribute *attr, const char *buffer, size_t size) 168 { 169 struct ttm_pool_manager *m = 170 container_of(kobj, struct ttm_pool_manager, kobj); 171 int chars; 172 unsigned val; 173 chars = ksscanf(buffer, "%u", &val); 174 if (chars == 0) 175 return size; 176 177 /* Convert kb to number of pages */ 178 val = val / (PAGE_SIZE >> 10); 179 180 if (attr == &ttm_page_pool_max) 181 m->options.max_size = val; 182 else if (attr == &ttm_page_pool_small) 183 m->options.small = val; 184 else if (attr == &ttm_page_pool_alloc_size) { 185 if (val > NUM_PAGES_TO_ALLOC*8) { 186 pr_err("Setting allocation size to %lu is not allowed. Recommended size is %lu\n", 187 NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 7), 188 NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 10)); 189 return size; 190 } else if (val > NUM_PAGES_TO_ALLOC) { 191 pr_warn("Setting allocation size to larger than %lu is not recommended\n", 192 NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 10)); 193 } 194 m->options.alloc_size = val; 195 } 196 197 return size; 198 } 199 200 static ssize_t ttm_pool_show(struct kobject *kobj, 201 struct attribute *attr, char *buffer) 202 { 203 struct ttm_pool_manager *m = 204 container_of(kobj, struct ttm_pool_manager, kobj); 205 unsigned val = 0; 206 207 if (attr == &ttm_page_pool_max) 208 val = m->options.max_size; 209 else if (attr == &ttm_page_pool_small) 210 val = m->options.small; 211 else if (attr == &ttm_page_pool_alloc_size) 212 val = m->options.alloc_size; 213 214 val = val * (PAGE_SIZE >> 10); 215 216 return ksnprintf(buffer, PAGE_SIZE, "%u\n", val); 217 } 218 219 static const struct sysfs_ops ttm_pool_sysfs_ops = { 220 .show = &ttm_pool_show, 221 .store = &ttm_pool_store, 222 }; 223 224 static struct kobj_type ttm_pool_kobj_type = { 225 .release = &ttm_pool_kobj_release, 226 .sysfs_ops = &ttm_pool_sysfs_ops, 227 .default_attrs = ttm_pool_attrs, 228 }; 229 230 static struct ttm_pool_manager *_manager; 231 232 #ifndef CONFIG_X86 233 static int set_pages_wb(struct page *page, int numpages) 234 { 235 #if IS_ENABLED(CONFIG_AGP) 236 int i; 237 238 for (i = 0; i < numpages; i++) 239 unmap_page_from_agp(page++); 240 #endif 241 return 0; 242 } 243 244 static int set_pages_array_wb(struct page **pages, int addrinarray) 245 { 246 #if IS_ENABLED(CONFIG_AGP) 247 int i; 248 249 for (i = 0; i < addrinarray; i++) 250 unmap_page_from_agp(pages[i]); 251 #endif 252 return 0; 253 } 254 255 static int set_pages_array_wc(struct page **pages, int addrinarray) 256 { 257 #if IS_ENABLED(CONFIG_AGP) 258 int i; 259 260 for (i = 0; i < addrinarray; i++) 261 map_page_into_agp(pages[i]); 262 #endif 263 return 0; 264 } 265 266 static int set_pages_array_uc(struct page **pages, int addrinarray) 267 { 268 #if IS_ENABLED(CONFIG_AGP) 269 int i; 270 271 for (i = 0; i < addrinarray; i++) 272 map_page_into_agp(pages[i]); 273 #endif 274 return 0; 275 } 276 #endif 277 278 /** 279 * Select the right pool or requested caching state and ttm flags. */ 280 static struct ttm_page_pool *ttm_get_pool(int flags, 281 enum ttm_caching_state cstate) 282 { 283 int pool_index; 284 285 if (cstate == tt_cached) 286 return NULL; 287 288 if (cstate == tt_wc) 289 pool_index = 0x0; 290 else 291 pool_index = 0x1; 292 293 if (flags & TTM_PAGE_FLAG_DMA32) 294 pool_index |= 0x2; 295 296 return &_manager->pools[pool_index]; 297 } 298 299 /* set memory back to wb and free the pages. */ 300 static void ttm_pages_put(struct page *pages[], unsigned npages) 301 { 302 unsigned i; 303 if (set_pages_array_wb(pages, npages)) 304 pr_err("Failed to set %d pages to wb!\n", npages); 305 for (i = 0; i < npages; ++i) { 306 __free_page(pages[i]); 307 } 308 } 309 310 static void ttm_pool_update_free_locked(struct ttm_page_pool *pool, 311 unsigned freed_pages) 312 { 313 pool->npages -= freed_pages; 314 pool->nfrees += freed_pages; 315 } 316 317 /** 318 * Free pages from pool. 319 * 320 * To prevent hogging the ttm_swap process we only free NUM_PAGES_TO_ALLOC 321 * number of pages in one go. 322 * 323 * @pool: to free the pages from 324 * @free_all: If set to true will free all pages in pool 325 * @use_static: Safe to use static buffer 326 **/ 327 static int ttm_page_pool_free(struct ttm_page_pool *pool, unsigned nr_free, 328 bool use_static) 329 { 330 static struct page *static_buf[NUM_PAGES_TO_ALLOC]; 331 unsigned long irq_flags; 332 struct vm_page *p, *p1; 333 struct page **pages_to_free; 334 unsigned freed_pages = 0, 335 npages_to_free = nr_free; 336 unsigned i; 337 338 if (NUM_PAGES_TO_ALLOC < nr_free) 339 npages_to_free = NUM_PAGES_TO_ALLOC; 340 341 if (use_static) 342 pages_to_free = static_buf; 343 else 344 pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), 345 M_DRM, GFP_KERNEL); 346 if (!pages_to_free) { 347 pr_err("Failed to allocate memory for pool free operation\n"); 348 return 0; 349 } 350 351 restart: 352 spin_lock_irqsave(&pool->lock, irq_flags); 353 354 TAILQ_FOREACH_REVERSE_MUTABLE(p, &pool->list, pglist, pageq, p1) { 355 if (freed_pages >= npages_to_free) 356 break; 357 358 pages_to_free[freed_pages++] = (struct page *)p; 359 /* We can only remove NUM_PAGES_TO_ALLOC at a time. */ 360 if (freed_pages >= NUM_PAGES_TO_ALLOC) { 361 /* remove range of pages from the pool */ 362 for (i = 0; i < freed_pages; i++) 363 TAILQ_REMOVE(&pool->list, (struct vm_page *)pages_to_free[i], pageq); 364 365 ttm_pool_update_free_locked(pool, freed_pages); 366 /** 367 * Because changing page caching is costly 368 * we unlock the pool to prevent stalling. 369 */ 370 spin_unlock_irqrestore(&pool->lock, irq_flags); 371 372 ttm_pages_put(pages_to_free, freed_pages); 373 if (likely(nr_free != FREE_ALL_PAGES)) 374 nr_free -= freed_pages; 375 376 if (NUM_PAGES_TO_ALLOC >= nr_free) 377 npages_to_free = nr_free; 378 else 379 npages_to_free = NUM_PAGES_TO_ALLOC; 380 381 freed_pages = 0; 382 383 /* free all so restart the processing */ 384 if (nr_free) 385 goto restart; 386 387 /* Not allowed to fall through or break because 388 * following context is inside spinlock while we are 389 * outside here. 390 */ 391 goto out; 392 393 } 394 } 395 396 /* remove range of pages from the pool */ 397 if (freed_pages) { 398 for (i = 0; i < freed_pages; i++) 399 TAILQ_REMOVE(&pool->list, (struct vm_page *)pages_to_free[i], pageq); 400 401 ttm_pool_update_free_locked(pool, freed_pages); 402 nr_free -= freed_pages; 403 } 404 405 spin_unlock_irqrestore(&pool->lock, irq_flags); 406 407 if (freed_pages) 408 ttm_pages_put(pages_to_free, freed_pages); 409 out: 410 if (pages_to_free != static_buf) 411 kfree(pages_to_free); 412 return nr_free; 413 } 414 415 /** 416 * Callback for mm to request pool to reduce number of page held. 417 * 418 * XXX: (dchinner) Deadlock warning! 419 * 420 * This code is crying out for a shrinker per pool.... 421 */ 422 static unsigned long 423 ttm_pool_shrink_scan(void *arg) 424 { 425 #ifdef __DragonFly__ 426 static struct shrink_control __sc; 427 struct shrink_control *sc = &__sc; 428 #endif 429 static DEFINE_MUTEX(lock); 430 static unsigned start_pool; 431 unsigned i; 432 unsigned pool_offset; 433 struct ttm_page_pool *pool; 434 int shrink_pages = 100; /* XXXKIB */ 435 unsigned long freed = 0; 436 437 #ifdef __DragonFly__ 438 sc->gfp_mask = M_WAITOK; 439 #endif 440 441 if (!mutex_trylock(&lock)) 442 return SHRINK_STOP; 443 pool_offset = ++start_pool % NUM_POOLS; 444 /* select start pool in round robin fashion */ 445 for (i = 0; i < NUM_POOLS; ++i) { 446 unsigned nr_free = shrink_pages; 447 if (shrink_pages == 0) 448 break; 449 pool = &_manager->pools[(i + pool_offset)%NUM_POOLS]; 450 /* OK to use static buffer since global mutex is held. */ 451 shrink_pages = ttm_page_pool_free(pool, nr_free, true); 452 freed += nr_free - shrink_pages; 453 } 454 mutex_unlock(&lock); 455 return freed; 456 } 457 458 459 static unsigned long 460 ttm_pool_shrink_count(struct shrinker *shrink, struct shrink_control *sc) 461 { 462 unsigned i; 463 unsigned long count = 0; 464 465 for (i = 0; i < NUM_POOLS; ++i) 466 count += _manager->pools[i].npages; 467 468 return count; 469 } 470 471 static void ttm_pool_mm_shrink_init(struct ttm_pool_manager *manager) 472 { 473 manager->mm_shrink.count_objects = ttm_pool_shrink_count; 474 manager->lowmem_handler = EVENTHANDLER_REGISTER(vm_lowmem, 475 ttm_pool_shrink_scan, manager, EVENTHANDLER_PRI_ANY); 476 } 477 478 static void ttm_pool_mm_shrink_fini(struct ttm_pool_manager *manager) 479 { 480 EVENTHANDLER_DEREGISTER(vm_lowmem, manager->lowmem_handler); 481 } 482 483 static int ttm_set_pages_caching(struct page **pages, 484 enum ttm_caching_state cstate, unsigned cpages) 485 { 486 int r = 0; 487 /* Set page caching */ 488 switch (cstate) { 489 case tt_uncached: 490 r = set_pages_array_uc(pages, cpages); 491 if (r) 492 pr_err("Failed to set %d pages to uc!\n", cpages); 493 break; 494 case tt_wc: 495 r = set_pages_array_wc(pages, cpages); 496 if (r) 497 pr_err("Failed to set %d pages to wc!\n", cpages); 498 break; 499 default: 500 break; 501 } 502 return r; 503 } 504 505 /** 506 * Free pages the pages that failed to change the caching state. If there is 507 * any pages that have changed their caching state already put them to the 508 * pool. 509 */ 510 static void ttm_handle_caching_state_failure(struct pglist *pages, 511 int ttm_flags, enum ttm_caching_state cstate, 512 struct page **failed_pages, unsigned cpages) 513 { 514 unsigned i; 515 /* Failed pages have to be freed */ 516 for (i = 0; i < cpages; ++i) { 517 TAILQ_REMOVE(pages, (struct vm_page *)failed_pages[i], pageq); 518 __free_page(failed_pages[i]); 519 } 520 } 521 522 /** 523 * Allocate new pages with correct caching. 524 * 525 * This function is reentrant if caller updates count depending on number of 526 * pages returned in pages array. 527 */ 528 static int ttm_alloc_new_pages(struct pglist *pages, gfp_t gfp_flags, 529 int ttm_flags, enum ttm_caching_state cstate, unsigned count) 530 { 531 struct page **caching_array; 532 struct page *p; 533 int r = 0; 534 unsigned i, cpages; 535 unsigned max_cpages = min(count, 536 (unsigned)(PAGE_SIZE/sizeof(struct page *))); 537 538 /* allocate array for page caching change */ 539 caching_array = kmalloc(max_cpages*sizeof(struct page *), M_DRM, M_WAITOK); 540 541 if (!caching_array) { 542 pr_err("Unable to allocate table for new pages\n"); 543 return -ENOMEM; 544 } 545 546 for (i = 0, cpages = 0; i < count; ++i) { 547 p = alloc_page(gfp_flags); 548 549 if (!p) { 550 pr_err("Unable to get page %u\n", i); 551 552 /* store already allocated pages in the pool after 553 * setting the caching state */ 554 if (cpages) { 555 r = ttm_set_pages_caching(caching_array, 556 cstate, cpages); 557 if (r) 558 ttm_handle_caching_state_failure(pages, 559 ttm_flags, cstate, 560 caching_array, cpages); 561 } 562 r = -ENOMEM; 563 goto out; 564 } 565 566 #ifdef CONFIG_HIGHMEM 567 /* gfp flags of highmem page should never be dma32 so we 568 * we should be fine in such case 569 */ 570 if (!PageHighMem(p)) 571 #endif 572 { 573 caching_array[cpages++] = p; 574 if (cpages == max_cpages) { 575 576 r = ttm_set_pages_caching(caching_array, 577 cstate, cpages); 578 if (r) { 579 ttm_handle_caching_state_failure(pages, 580 ttm_flags, cstate, 581 caching_array, cpages); 582 goto out; 583 } 584 cpages = 0; 585 } 586 } 587 588 TAILQ_INSERT_HEAD(pages, (struct vm_page *)p, pageq); 589 } 590 591 if (cpages) { 592 r = ttm_set_pages_caching(caching_array, cstate, cpages); 593 if (r) 594 ttm_handle_caching_state_failure(pages, 595 ttm_flags, cstate, 596 caching_array, cpages); 597 } 598 out: 599 kfree(caching_array); 600 601 return r; 602 } 603 604 /** 605 * Fill the given pool if there aren't enough pages and the requested number of 606 * pages is small. 607 */ 608 static void ttm_page_pool_fill_locked(struct ttm_page_pool *pool, 609 int ttm_flags, enum ttm_caching_state cstate, unsigned count, 610 unsigned long *irq_flags) 611 { 612 vm_page_t p; 613 int r; 614 unsigned cpages = 0; 615 /** 616 * Only allow one pool fill operation at a time. 617 * If pool doesn't have enough pages for the allocation new pages are 618 * allocated from outside of pool. 619 */ 620 if (pool->fill_lock) 621 return; 622 623 pool->fill_lock = true; 624 625 /* If allocation request is small and there are not enough 626 * pages in a pool we fill the pool up first. */ 627 if (count < _manager->options.small 628 && count > pool->npages) { 629 struct pglist new_pages; 630 unsigned alloc_size = _manager->options.alloc_size; 631 632 /** 633 * Can't change page caching if in irqsave context. We have to 634 * drop the pool->lock. 635 */ 636 spin_unlock_irqrestore(&pool->lock, *irq_flags); 637 638 TAILQ_INIT(&new_pages); 639 r = ttm_alloc_new_pages(&new_pages, pool->gfp_flags, ttm_flags, 640 cstate, alloc_size); 641 spin_lock_irqsave(&pool->lock, *irq_flags); 642 643 if (!r) { 644 TAILQ_CONCAT(&pool->list, &new_pages, pageq); 645 ++pool->nrefills; 646 pool->npages += alloc_size; 647 } else { 648 pr_err("Failed to fill pool (%p)\n", pool); 649 /* If we have any pages left put them to the pool. */ 650 TAILQ_FOREACH(p, &new_pages, pageq) { 651 ++cpages; 652 } 653 TAILQ_CONCAT(&pool->list, &new_pages, pageq); 654 pool->npages += cpages; 655 } 656 657 } 658 pool->fill_lock = false; 659 } 660 661 /** 662 * Cut 'count' number of pages from the pool and put them on the return list. 663 * 664 * @return count of pages still required to fulfill the request. 665 */ 666 static unsigned ttm_page_pool_get_pages(struct ttm_page_pool *pool, 667 struct pglist *pages, 668 int ttm_flags, 669 enum ttm_caching_state cstate, 670 unsigned count) 671 { 672 unsigned long irq_flags; 673 vm_page_t p; 674 unsigned i; 675 676 spin_lock_irqsave(&pool->lock, irq_flags); 677 ttm_page_pool_fill_locked(pool, ttm_flags, cstate, count, &irq_flags); 678 679 if (count >= pool->npages) { 680 /* take all pages from the pool */ 681 TAILQ_CONCAT(pages, &pool->list, pageq); 682 count -= pool->npages; 683 pool->npages = 0; 684 goto out; 685 } 686 for (i = 0; i < count; i++) { 687 p = TAILQ_FIRST(&pool->list); 688 TAILQ_REMOVE(&pool->list, p, pageq); 689 TAILQ_INSERT_TAIL(pages, p, pageq); 690 } 691 pool->npages -= count; 692 count = 0; 693 out: 694 spin_unlock_irqrestore(&pool->lock, irq_flags); 695 return count; 696 } 697 698 /* Put all pages in pages list to correct pool to wait for reuse */ 699 static void ttm_put_pages(struct page **pages, unsigned npages, int flags, 700 enum ttm_caching_state cstate) 701 { 702 unsigned long irq_flags; 703 struct ttm_page_pool *pool = ttm_get_pool(flags, cstate); 704 unsigned i; 705 struct vm_page *page; 706 707 if (pool == NULL) { 708 /* No pool for this memory type so free the pages */ 709 for (i = 0; i < npages; i++) { 710 if (pages[i]) { 711 #if 0 712 if (page_count(pages[i]) != 1) 713 pr_err("Erroneous page count. Leaking pages.\n"); 714 #endif 715 __free_page(pages[i]); 716 pages[i] = NULL; 717 } 718 } 719 return; 720 } 721 722 spin_lock_irqsave(&pool->lock, irq_flags); 723 for (i = 0; i < npages; i++) { 724 if (pages[i]) { 725 page = (struct vm_page *)pages[i]; 726 TAILQ_INSERT_TAIL(&pool->list, page, pageq); 727 pages[i] = NULL; 728 pool->npages++; 729 } 730 } 731 /* Check that we don't go over the pool limit */ 732 npages = 0; 733 if (pool->npages > _manager->options.max_size) { 734 npages = pool->npages - _manager->options.max_size; 735 /* free at least NUM_PAGES_TO_ALLOC number of pages 736 * to reduce calls to set_memory_wb */ 737 if (npages < NUM_PAGES_TO_ALLOC) 738 npages = NUM_PAGES_TO_ALLOC; 739 } 740 spin_unlock_irqrestore(&pool->lock, irq_flags); 741 if (npages) 742 ttm_page_pool_free(pool, npages, false); 743 } 744 745 /* 746 * On success pages list will hold count number of correctly 747 * cached pages. 748 */ 749 static int ttm_get_pages(struct page **pages, unsigned npages, int flags, 750 enum ttm_caching_state cstate) 751 { 752 struct ttm_page_pool *pool = ttm_get_pool(flags, cstate); 753 struct pglist plist; 754 struct vm_page *p = NULL; 755 gfp_t gfp_flags = GFP_USER; 756 unsigned count; 757 int r; 758 759 /* set zero flag for page allocation if required */ 760 if (flags & TTM_PAGE_FLAG_ZERO_ALLOC) 761 gfp_flags |= __GFP_ZERO; 762 763 /* No pool for cached pages */ 764 if (pool == NULL) { 765 if (flags & TTM_PAGE_FLAG_DMA32) 766 gfp_flags |= GFP_DMA32; 767 else 768 gfp_flags |= GFP_HIGHUSER; 769 770 for (r = 0; r < npages; ++r) { 771 p = (struct vm_page *)alloc_page(gfp_flags); 772 if (!p) { 773 774 pr_err("Unable to allocate page\n"); 775 return -ENOMEM; 776 } 777 pages[r] = (struct page *)p; 778 } 779 return 0; 780 } 781 782 /* combine zero flag to pool flags */ 783 gfp_flags |= pool->gfp_flags; 784 785 /* First we take pages from the pool */ 786 TAILQ_INIT(&plist); 787 npages = ttm_page_pool_get_pages(pool, &plist, flags, cstate, npages); 788 count = 0; 789 TAILQ_FOREACH(p, &plist, pageq) { 790 pages[count++] = (struct page *)p; 791 } 792 793 /* clear the pages coming from the pool if requested */ 794 if (flags & TTM_PAGE_FLAG_ZERO_ALLOC) { 795 TAILQ_FOREACH(p, &plist, pageq) { 796 pmap_zero_page(VM_PAGE_TO_PHYS(p)); 797 } 798 } 799 800 /* If pool didn't have enough pages allocate new one. */ 801 if (npages > 0) { 802 /* ttm_alloc_new_pages doesn't reference pool so we can run 803 * multiple requests in parallel. 804 **/ 805 TAILQ_INIT(&plist); 806 r = ttm_alloc_new_pages(&plist, gfp_flags, flags, cstate, npages); 807 TAILQ_FOREACH(p, &plist, pageq) { 808 pages[count++] = (struct page *)p; 809 } 810 if (r) { 811 /* If there is any pages in the list put them back to 812 * the pool. */ 813 pr_err("Failed to allocate extra pages for large request\n"); 814 ttm_put_pages(pages, count, flags, cstate); 815 return r; 816 } 817 } 818 819 return 0; 820 } 821 822 static void ttm_page_pool_init_locked(struct ttm_page_pool *pool, gfp_t flags, 823 char *name) 824 { 825 lockinit(&pool->lock, "ttmpool", 0, LK_CANRECURSE); 826 pool->fill_lock = false; 827 TAILQ_INIT(&pool->list); 828 pool->npages = pool->nfrees = 0; 829 pool->gfp_flags = flags; 830 pool->name = name; 831 } 832 833 int ttm_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages) 834 { 835 int ret; 836 837 WARN_ON(_manager); 838 839 pr_info("Initializing pool allocator\n"); 840 841 _manager = kzalloc(sizeof(*_manager), GFP_KERNEL); 842 if (!_manager) 843 return -ENOMEM; 844 845 ttm_page_pool_init_locked(&_manager->wc_pool, GFP_HIGHUSER, "wc"); 846 847 ttm_page_pool_init_locked(&_manager->uc_pool, GFP_HIGHUSER, "uc"); 848 849 ttm_page_pool_init_locked(&_manager->wc_pool_dma32, 850 GFP_USER | GFP_DMA32, "wc dma"); 851 852 ttm_page_pool_init_locked(&_manager->uc_pool_dma32, 853 GFP_USER | GFP_DMA32, "uc dma"); 854 855 _manager->options.max_size = max_pages; 856 _manager->options.small = SMALL_ALLOCATION; 857 _manager->options.alloc_size = NUM_PAGES_TO_ALLOC; 858 859 ret = kobject_init_and_add(&_manager->kobj, &ttm_pool_kobj_type, 860 &glob->kobj, "pool"); 861 if (unlikely(ret != 0)) { 862 kobject_put(&_manager->kobj); 863 _manager = NULL; 864 return ret; 865 } 866 867 ttm_pool_mm_shrink_init(_manager); 868 869 return 0; 870 } 871 872 void ttm_page_alloc_fini(void) 873 { 874 int i; 875 876 pr_info("Finalizing pool allocator\n"); 877 ttm_pool_mm_shrink_fini(_manager); 878 879 /* OK to use static buffer since global mutex is no longer used. */ 880 for (i = 0; i < NUM_POOLS; ++i) 881 ttm_page_pool_free(&_manager->pools[i], FREE_ALL_PAGES, true); 882 883 kobject_put(&_manager->kobj); 884 _manager = NULL; 885 } 886 887 int ttm_pool_populate(struct ttm_tt *ttm) 888 { 889 struct ttm_mem_global *mem_glob = ttm->glob->mem_glob; 890 unsigned i; 891 int ret; 892 893 if (ttm->state != tt_unpopulated) 894 return 0; 895 896 ret = ttm_get_pages(ttm->pages, ttm->num_pages, ttm->page_flags, 897 ttm->caching_state); 898 if (unlikely(ret != 0)) { 899 ttm_pool_unpopulate(ttm); 900 return ret; 901 } 902 903 for (i = 0; i < ttm->num_pages; ++i) { 904 ret = ttm_mem_global_alloc_page(mem_glob, ttm->pages[i], 905 PAGE_SIZE); 906 if (unlikely(ret != 0)) { 907 ttm_pool_unpopulate(ttm); 908 return -ENOMEM; 909 } 910 } 911 912 if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { 913 ret = ttm_tt_swapin(ttm); 914 if (unlikely(ret != 0)) { 915 ttm_pool_unpopulate(ttm); 916 return ret; 917 } 918 } 919 920 ttm->state = tt_unbound; 921 return 0; 922 } 923 EXPORT_SYMBOL(ttm_pool_populate); 924 925 void ttm_pool_unpopulate(struct ttm_tt *ttm) 926 { 927 unsigned i; 928 929 for (i = 0; i < ttm->num_pages; ++i) { 930 if (!ttm->pages[i]) 931 continue; 932 933 ttm_mem_global_free_page(ttm->glob->mem_glob, ttm->pages[i], 934 PAGE_SIZE); 935 } 936 ttm_put_pages(ttm->pages, ttm->num_pages, ttm->page_flags, 937 ttm->caching_state); 938 ttm->state = tt_unpopulated; 939 } 940 EXPORT_SYMBOL(ttm_pool_unpopulate); 941 942 int ttm_populate_and_map_pages(struct device *dev, struct ttm_dma_tt *tt) 943 { 944 unsigned i, j; 945 int r; 946 947 r = ttm_pool_populate(&tt->ttm); 948 if (r) 949 return r; 950 951 for (i = 0; i < tt->ttm.num_pages; ++i) { 952 struct page *p = tt->ttm.pages[i]; 953 size_t num_pages = 1; 954 955 for (j = i + 1; j < tt->ttm.num_pages; ++j) { 956 if (++p != tt->ttm.pages[j]) 957 break; 958 959 ++num_pages; 960 } 961 962 tt->dma_address[i] = dma_map_page(dev, tt->ttm.pages[i], 963 0, num_pages * PAGE_SIZE, 964 DMA_BIDIRECTIONAL); 965 if (dma_mapping_error(dev, tt->dma_address[i])) { 966 while (i--) { 967 dma_unmap_page(dev, tt->dma_address[i], 968 PAGE_SIZE, DMA_BIDIRECTIONAL); 969 tt->dma_address[i] = 0; 970 } 971 ttm_pool_unpopulate(&tt->ttm); 972 return -EFAULT; 973 } 974 975 for (j = 1; j < num_pages; ++j) { 976 tt->dma_address[i + 1] = tt->dma_address[i] + PAGE_SIZE; 977 ++i; 978 } 979 } 980 return 0; 981 } 982 EXPORT_SYMBOL(ttm_populate_and_map_pages); 983 984 void ttm_unmap_and_unpopulate_pages(struct device *dev, struct ttm_dma_tt *tt) 985 { 986 unsigned i, j; 987 988 for (i = 0; i < tt->ttm.num_pages;) { 989 struct page *p = tt->ttm.pages[i]; 990 size_t num_pages = 1; 991 992 if (!tt->dma_address[i] || !tt->ttm.pages[i]) { 993 ++i; 994 continue; 995 } 996 997 for (j = i + 1; j < tt->ttm.num_pages; ++j) { 998 if (++p != tt->ttm.pages[j]) 999 break; 1000 1001 ++num_pages; 1002 } 1003 1004 dma_unmap_page(dev, tt->dma_address[i], num_pages * PAGE_SIZE, 1005 DMA_BIDIRECTIONAL); 1006 1007 i += num_pages; 1008 } 1009 ttm_pool_unpopulate(&tt->ttm); 1010 } 1011 EXPORT_SYMBOL(ttm_unmap_and_unpopulate_pages); 1012 1013 #if 0 1014 int ttm_page_alloc_debugfs(struct seq_file *m, void *data) 1015 { 1016 struct ttm_page_pool *p; 1017 unsigned i; 1018 char *h[] = {"pool", "refills", "pages freed", "size"}; 1019 if (!_manager) { 1020 seq_printf(m, "No pool allocator running.\n"); 1021 return 0; 1022 } 1023 seq_printf(m, "%6s %12s %13s %8s\n", 1024 h[0], h[1], h[2], h[3]); 1025 for (i = 0; i < NUM_POOLS; ++i) { 1026 p = &_manager->pools[i]; 1027 1028 seq_printf(m, "%6s %12ld %13ld %8d\n", 1029 p->name, p->nrefills, 1030 p->nfrees, p->npages); 1031 } 1032 return 0; 1033 } 1034 #endif 1035 EXPORT_SYMBOL(ttm_page_alloc_debugfs); 1036