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_array_wb(struct page **pages, int addrinarray) 234 { 235 #if IS_ENABLED(CONFIG_AGP) 236 int i; 237 238 for (i = 0; i < addrinarray; i++) 239 unmap_page_from_agp(pages[i]); 240 #endif 241 return 0; 242 } 243 244 static int set_pages_array_wc(struct page **pages, int addrinarray) 245 { 246 #if IS_ENABLED(CONFIG_AGP) 247 int i; 248 249 for (i = 0; i < addrinarray; i++) 250 map_page_into_agp(pages[i]); 251 #endif 252 return 0; 253 } 254 255 static int set_pages_array_uc(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 #endif 266 267 /** 268 * Select the right pool or requested caching state and ttm flags. */ 269 static struct ttm_page_pool *ttm_get_pool(int flags, 270 enum ttm_caching_state cstate) 271 { 272 int pool_index; 273 274 if (cstate == tt_cached) 275 return NULL; 276 277 if (cstate == tt_wc) 278 pool_index = 0x0; 279 else 280 pool_index = 0x1; 281 282 if (flags & TTM_PAGE_FLAG_DMA32) 283 pool_index |= 0x2; 284 285 return &_manager->pools[pool_index]; 286 } 287 288 /* set memory back to wb and free the pages. */ 289 static void ttm_pages_put(struct page *pages[], unsigned npages) 290 { 291 unsigned i; 292 if (set_pages_array_wb(pages, npages)) 293 pr_err("Failed to set %d pages to wb!\n", npages); 294 for (i = 0; i < npages; ++i) { 295 __free_page(pages[i]); 296 } 297 } 298 299 static void ttm_pool_update_free_locked(struct ttm_page_pool *pool, 300 unsigned freed_pages) 301 { 302 pool->npages -= freed_pages; 303 pool->nfrees += freed_pages; 304 } 305 306 /** 307 * Free pages from pool. 308 * 309 * To prevent hogging the ttm_swap process we only free NUM_PAGES_TO_ALLOC 310 * number of pages in one go. 311 * 312 * @pool: to free the pages from 313 * @free_all: If set to true will free all pages in pool 314 * @use_static: Safe to use static buffer 315 **/ 316 static int ttm_page_pool_free(struct ttm_page_pool *pool, unsigned nr_free, 317 bool use_static) 318 { 319 static struct page *static_buf[NUM_PAGES_TO_ALLOC]; 320 unsigned long irq_flags; 321 struct vm_page *p, *p1; 322 struct page **pages_to_free; 323 unsigned freed_pages = 0, 324 npages_to_free = nr_free; 325 unsigned i; 326 327 if (NUM_PAGES_TO_ALLOC < nr_free) 328 npages_to_free = NUM_PAGES_TO_ALLOC; 329 330 if (use_static) 331 pages_to_free = static_buf; 332 else 333 pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), 334 M_DRM, GFP_KERNEL); 335 if (!pages_to_free) { 336 pr_err("Failed to allocate memory for pool free operation\n"); 337 return 0; 338 } 339 340 restart: 341 spin_lock_irqsave(&pool->lock, irq_flags); 342 343 TAILQ_FOREACH_REVERSE_MUTABLE(p, &pool->list, pglist, pageq, p1) { 344 if (freed_pages >= npages_to_free) 345 break; 346 347 pages_to_free[freed_pages++] = (struct page *)p; 348 /* We can only remove NUM_PAGES_TO_ALLOC at a time. */ 349 if (freed_pages >= NUM_PAGES_TO_ALLOC) { 350 /* remove range of pages from the pool */ 351 for (i = 0; i < freed_pages; i++) 352 TAILQ_REMOVE(&pool->list, (struct vm_page *)pages_to_free[i], pageq); 353 354 ttm_pool_update_free_locked(pool, freed_pages); 355 /** 356 * Because changing page caching is costly 357 * we unlock the pool to prevent stalling. 358 */ 359 spin_unlock_irqrestore(&pool->lock, irq_flags); 360 361 ttm_pages_put(pages_to_free, freed_pages); 362 if (likely(nr_free != FREE_ALL_PAGES)) 363 nr_free -= freed_pages; 364 365 if (NUM_PAGES_TO_ALLOC >= nr_free) 366 npages_to_free = nr_free; 367 else 368 npages_to_free = NUM_PAGES_TO_ALLOC; 369 370 freed_pages = 0; 371 372 /* free all so restart the processing */ 373 if (nr_free) 374 goto restart; 375 376 /* Not allowed to fall through or break because 377 * following context is inside spinlock while we are 378 * outside here. 379 */ 380 goto out; 381 382 } 383 } 384 385 /* remove range of pages from the pool */ 386 if (freed_pages) { 387 for (i = 0; i < freed_pages; i++) 388 TAILQ_REMOVE(&pool->list, (struct vm_page *)pages_to_free[i], pageq); 389 390 ttm_pool_update_free_locked(pool, freed_pages); 391 nr_free -= freed_pages; 392 } 393 394 spin_unlock_irqrestore(&pool->lock, irq_flags); 395 396 if (freed_pages) 397 ttm_pages_put(pages_to_free, freed_pages); 398 out: 399 if (pages_to_free != static_buf) 400 kfree(pages_to_free); 401 return nr_free; 402 } 403 404 /** 405 * Callback for mm to request pool to reduce number of page held. 406 * 407 * XXX: (dchinner) Deadlock warning! 408 * 409 * This code is crying out for a shrinker per pool.... 410 */ 411 static unsigned long 412 ttm_pool_shrink_scan(void *arg) 413 { 414 #ifdef __DragonFly__ 415 static struct shrink_control __sc; 416 struct shrink_control *sc = &__sc; 417 #endif 418 static DEFINE_MUTEX(lock); 419 static unsigned start_pool; 420 unsigned i; 421 unsigned pool_offset; 422 struct ttm_page_pool *pool; 423 int shrink_pages = 100; /* XXXKIB */ 424 unsigned long freed = 0; 425 426 #ifdef __DragonFly__ 427 sc->gfp_mask = M_WAITOK; 428 #endif 429 430 if (!mutex_trylock(&lock)) 431 return SHRINK_STOP; 432 pool_offset = ++start_pool % NUM_POOLS; 433 /* select start pool in round robin fashion */ 434 for (i = 0; i < NUM_POOLS; ++i) { 435 unsigned nr_free = shrink_pages; 436 if (shrink_pages == 0) 437 break; 438 pool = &_manager->pools[(i + pool_offset)%NUM_POOLS]; 439 /* OK to use static buffer since global mutex is held. */ 440 shrink_pages = ttm_page_pool_free(pool, nr_free, true); 441 freed += nr_free - shrink_pages; 442 } 443 mutex_unlock(&lock); 444 return freed; 445 } 446 447 448 static unsigned long 449 ttm_pool_shrink_count(struct shrinker *shrink, struct shrink_control *sc) 450 { 451 unsigned i; 452 unsigned long count = 0; 453 454 for (i = 0; i < NUM_POOLS; ++i) 455 count += _manager->pools[i].npages; 456 457 return count; 458 } 459 460 static void ttm_pool_mm_shrink_init(struct ttm_pool_manager *manager) 461 { 462 manager->mm_shrink.count_objects = ttm_pool_shrink_count; 463 manager->lowmem_handler = EVENTHANDLER_REGISTER(vm_lowmem, 464 ttm_pool_shrink_scan, manager, EVENTHANDLER_PRI_ANY); 465 } 466 467 static void ttm_pool_mm_shrink_fini(struct ttm_pool_manager *manager) 468 { 469 EVENTHANDLER_DEREGISTER(vm_lowmem, manager->lowmem_handler); 470 } 471 472 static int ttm_set_pages_caching(struct page **pages, 473 enum ttm_caching_state cstate, unsigned cpages) 474 { 475 int r = 0; 476 /* Set page caching */ 477 switch (cstate) { 478 case tt_uncached: 479 r = set_pages_array_uc(pages, cpages); 480 if (r) 481 pr_err("Failed to set %d pages to uc!\n", cpages); 482 break; 483 case tt_wc: 484 r = set_pages_array_wc(pages, cpages); 485 if (r) 486 pr_err("Failed to set %d pages to wc!\n", cpages); 487 break; 488 default: 489 break; 490 } 491 return r; 492 } 493 494 /** 495 * Free pages the pages that failed to change the caching state. If there is 496 * any pages that have changed their caching state already put them to the 497 * pool. 498 */ 499 static void ttm_handle_caching_state_failure(struct pglist *pages, 500 int ttm_flags, enum ttm_caching_state cstate, 501 struct page **failed_pages, unsigned cpages) 502 { 503 unsigned i; 504 /* Failed pages have to be freed */ 505 for (i = 0; i < cpages; ++i) { 506 TAILQ_REMOVE(pages, (struct vm_page *)failed_pages[i], pageq); 507 __free_page(failed_pages[i]); 508 } 509 } 510 511 /** 512 * Allocate new pages with correct caching. 513 * 514 * This function is reentrant if caller updates count depending on number of 515 * pages returned in pages array. 516 */ 517 static int ttm_alloc_new_pages(struct pglist *pages, gfp_t gfp_flags, 518 int ttm_flags, enum ttm_caching_state cstate, unsigned count) 519 { 520 struct page **caching_array; 521 struct page *p; 522 int r = 0; 523 unsigned i, cpages; 524 unsigned max_cpages = min(count, 525 (unsigned)(PAGE_SIZE/sizeof(struct page *))); 526 527 /* allocate array for page caching change */ 528 caching_array = kmalloc(max_cpages*sizeof(struct page *), M_DRM, M_WAITOK); 529 530 if (!caching_array) { 531 pr_err("Unable to allocate table for new pages\n"); 532 return -ENOMEM; 533 } 534 535 for (i = 0, cpages = 0; i < count; ++i) { 536 p = alloc_page(gfp_flags); 537 538 if (!p) { 539 pr_err("Unable to get page %u\n", i); 540 541 /* store already allocated pages in the pool after 542 * setting the caching state */ 543 if (cpages) { 544 r = ttm_set_pages_caching(caching_array, 545 cstate, cpages); 546 if (r) 547 ttm_handle_caching_state_failure(pages, 548 ttm_flags, cstate, 549 caching_array, cpages); 550 } 551 r = -ENOMEM; 552 goto out; 553 } 554 555 #ifdef CONFIG_HIGHMEM 556 /* gfp flags of highmem page should never be dma32 so we 557 * we should be fine in such case 558 */ 559 if (!PageHighMem(p)) 560 #endif 561 { 562 caching_array[cpages++] = p; 563 if (cpages == max_cpages) { 564 565 r = ttm_set_pages_caching(caching_array, 566 cstate, cpages); 567 if (r) { 568 ttm_handle_caching_state_failure(pages, 569 ttm_flags, cstate, 570 caching_array, cpages); 571 goto out; 572 } 573 cpages = 0; 574 } 575 } 576 577 TAILQ_INSERT_HEAD(pages, (struct vm_page *)p, pageq); 578 } 579 580 if (cpages) { 581 r = ttm_set_pages_caching(caching_array, cstate, cpages); 582 if (r) 583 ttm_handle_caching_state_failure(pages, 584 ttm_flags, cstate, 585 caching_array, cpages); 586 } 587 out: 588 kfree(caching_array); 589 590 return r; 591 } 592 593 /** 594 * Fill the given pool if there aren't enough pages and the requested number of 595 * pages is small. 596 */ 597 static void ttm_page_pool_fill_locked(struct ttm_page_pool *pool, 598 int ttm_flags, enum ttm_caching_state cstate, unsigned count, 599 unsigned long *irq_flags) 600 { 601 vm_page_t p; 602 int r; 603 unsigned cpages = 0; 604 /** 605 * Only allow one pool fill operation at a time. 606 * If pool doesn't have enough pages for the allocation new pages are 607 * allocated from outside of pool. 608 */ 609 if (pool->fill_lock) 610 return; 611 612 pool->fill_lock = true; 613 614 /* If allocation request is small and there are not enough 615 * pages in a pool we fill the pool up first. */ 616 if (count < _manager->options.small 617 && count > pool->npages) { 618 struct pglist new_pages; 619 unsigned alloc_size = _manager->options.alloc_size; 620 621 /** 622 * Can't change page caching if in irqsave context. We have to 623 * drop the pool->lock. 624 */ 625 spin_unlock_irqrestore(&pool->lock, *irq_flags); 626 627 TAILQ_INIT(&new_pages); 628 r = ttm_alloc_new_pages(&new_pages, pool->gfp_flags, ttm_flags, 629 cstate, alloc_size); 630 spin_lock_irqsave(&pool->lock, *irq_flags); 631 632 if (!r) { 633 TAILQ_CONCAT(&pool->list, &new_pages, pageq); 634 ++pool->nrefills; 635 pool->npages += alloc_size; 636 } else { 637 pr_err("Failed to fill pool (%p)\n", pool); 638 /* If we have any pages left put them to the pool. */ 639 TAILQ_FOREACH(p, &new_pages, pageq) { 640 ++cpages; 641 } 642 TAILQ_CONCAT(&pool->list, &new_pages, pageq); 643 pool->npages += cpages; 644 } 645 646 } 647 pool->fill_lock = false; 648 } 649 650 /** 651 * Cut 'count' number of pages from the pool and put them on the return list. 652 * 653 * @return count of pages still required to fulfill the request. 654 */ 655 static unsigned ttm_page_pool_get_pages(struct ttm_page_pool *pool, 656 struct pglist *pages, 657 int ttm_flags, 658 enum ttm_caching_state cstate, 659 unsigned count) 660 { 661 unsigned long irq_flags; 662 vm_page_t p; 663 unsigned i; 664 665 spin_lock_irqsave(&pool->lock, irq_flags); 666 ttm_page_pool_fill_locked(pool, ttm_flags, cstate, count, &irq_flags); 667 668 if (count >= pool->npages) { 669 /* take all pages from the pool */ 670 TAILQ_CONCAT(pages, &pool->list, pageq); 671 count -= pool->npages; 672 pool->npages = 0; 673 goto out; 674 } 675 for (i = 0; i < count; i++) { 676 p = TAILQ_FIRST(&pool->list); 677 TAILQ_REMOVE(&pool->list, p, pageq); 678 TAILQ_INSERT_TAIL(pages, p, pageq); 679 } 680 pool->npages -= count; 681 count = 0; 682 out: 683 spin_unlock_irqrestore(&pool->lock, irq_flags); 684 return count; 685 } 686 687 /* Put all pages in pages list to correct pool to wait for reuse */ 688 static void ttm_put_pages(struct page **pages, unsigned npages, int flags, 689 enum ttm_caching_state cstate) 690 { 691 unsigned long irq_flags; 692 struct ttm_page_pool *pool = ttm_get_pool(flags, cstate); 693 unsigned i; 694 struct vm_page *page; 695 696 if (pool == NULL) { 697 /* No pool for this memory type so free the pages */ 698 for (i = 0; i < npages; i++) { 699 if (pages[i]) { 700 #if 0 701 if (page_count(pages[i]) != 1) 702 pr_err("Erroneous page count. Leaking pages.\n"); 703 #endif 704 __free_page(pages[i]); 705 pages[i] = NULL; 706 } 707 } 708 return; 709 } 710 711 spin_lock_irqsave(&pool->lock, irq_flags); 712 for (i = 0; i < npages; i++) { 713 if (pages[i]) { 714 page = (struct vm_page *)pages[i]; 715 TAILQ_INSERT_TAIL(&pool->list, page, pageq); 716 pages[i] = NULL; 717 pool->npages++; 718 } 719 } 720 /* Check that we don't go over the pool limit */ 721 npages = 0; 722 if (pool->npages > _manager->options.max_size) { 723 npages = pool->npages - _manager->options.max_size; 724 /* free at least NUM_PAGES_TO_ALLOC number of pages 725 * to reduce calls to set_memory_wb */ 726 if (npages < NUM_PAGES_TO_ALLOC) 727 npages = NUM_PAGES_TO_ALLOC; 728 } 729 spin_unlock_irqrestore(&pool->lock, irq_flags); 730 if (npages) 731 ttm_page_pool_free(pool, npages, false); 732 } 733 734 /* 735 * On success pages list will hold count number of correctly 736 * cached pages. 737 */ 738 static int ttm_get_pages(struct page **pages, unsigned npages, int flags, 739 enum ttm_caching_state cstate) 740 { 741 struct ttm_page_pool *pool = ttm_get_pool(flags, cstate); 742 struct pglist plist; 743 struct vm_page *p = NULL; 744 gfp_t gfp_flags = GFP_USER; 745 unsigned count; 746 int r; 747 748 /* set zero flag for page allocation if required */ 749 if (flags & TTM_PAGE_FLAG_ZERO_ALLOC) 750 gfp_flags |= __GFP_ZERO; 751 752 /* No pool for cached pages */ 753 if (pool == NULL) { 754 if (flags & TTM_PAGE_FLAG_DMA32) 755 gfp_flags |= GFP_DMA32; 756 else 757 gfp_flags |= GFP_HIGHUSER; 758 759 for (r = 0; r < npages; ++r) { 760 p = (struct vm_page *)alloc_page(gfp_flags); 761 if (!p) { 762 763 pr_err("Unable to allocate page\n"); 764 return -ENOMEM; 765 } 766 pages[r] = (struct page *)p; 767 } 768 return 0; 769 } 770 771 /* combine zero flag to pool flags */ 772 gfp_flags |= pool->gfp_flags; 773 774 /* First we take pages from the pool */ 775 TAILQ_INIT(&plist); 776 npages = ttm_page_pool_get_pages(pool, &plist, flags, cstate, npages); 777 count = 0; 778 TAILQ_FOREACH(p, &plist, pageq) { 779 pages[count++] = (struct page *)p; 780 } 781 782 /* clear the pages coming from the pool if requested */ 783 if (flags & TTM_PAGE_FLAG_ZERO_ALLOC) { 784 TAILQ_FOREACH(p, &plist, pageq) { 785 pmap_zero_page(VM_PAGE_TO_PHYS(p)); 786 } 787 } 788 789 /* If pool didn't have enough pages allocate new one. */ 790 if (npages > 0) { 791 /* ttm_alloc_new_pages doesn't reference pool so we can run 792 * multiple requests in parallel. 793 **/ 794 TAILQ_INIT(&plist); 795 r = ttm_alloc_new_pages(&plist, gfp_flags, flags, cstate, npages); 796 TAILQ_FOREACH(p, &plist, pageq) { 797 pages[count++] = (struct page *)p; 798 } 799 if (r) { 800 /* If there is any pages in the list put them back to 801 * the pool. */ 802 pr_err("Failed to allocate extra pages for large request\n"); 803 ttm_put_pages(pages, count, flags, cstate); 804 return r; 805 } 806 } 807 808 return 0; 809 } 810 811 static void ttm_page_pool_init_locked(struct ttm_page_pool *pool, gfp_t flags, 812 char *name) 813 { 814 lockinit(&pool->lock, "ttmpool", 0, LK_CANRECURSE); 815 pool->fill_lock = false; 816 TAILQ_INIT(&pool->list); 817 pool->npages = pool->nfrees = 0; 818 pool->gfp_flags = flags; 819 pool->name = name; 820 } 821 822 int ttm_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages) 823 { 824 int ret; 825 826 WARN_ON(_manager); 827 828 pr_info("Initializing pool allocator\n"); 829 830 _manager = kzalloc(sizeof(*_manager), GFP_KERNEL); 831 832 ttm_page_pool_init_locked(&_manager->wc_pool, GFP_HIGHUSER, "wc"); 833 834 ttm_page_pool_init_locked(&_manager->uc_pool, GFP_HIGHUSER, "uc"); 835 836 ttm_page_pool_init_locked(&_manager->wc_pool_dma32, 837 GFP_USER | GFP_DMA32, "wc dma"); 838 839 ttm_page_pool_init_locked(&_manager->uc_pool_dma32, 840 GFP_USER | GFP_DMA32, "uc dma"); 841 842 _manager->options.max_size = max_pages; 843 _manager->options.small = SMALL_ALLOCATION; 844 _manager->options.alloc_size = NUM_PAGES_TO_ALLOC; 845 846 ret = kobject_init_and_add(&_manager->kobj, &ttm_pool_kobj_type, 847 &glob->kobj, "pool"); 848 if (unlikely(ret != 0)) { 849 kobject_put(&_manager->kobj); 850 _manager = NULL; 851 return ret; 852 } 853 854 ttm_pool_mm_shrink_init(_manager); 855 856 return 0; 857 } 858 859 void ttm_page_alloc_fini(void) 860 { 861 int i; 862 863 pr_info("Finalizing pool allocator\n"); 864 ttm_pool_mm_shrink_fini(_manager); 865 866 /* OK to use static buffer since global mutex is no longer used. */ 867 for (i = 0; i < NUM_POOLS; ++i) 868 ttm_page_pool_free(&_manager->pools[i], FREE_ALL_PAGES, true); 869 870 kobject_put(&_manager->kobj); 871 _manager = NULL; 872 } 873 874 int ttm_pool_populate(struct ttm_tt *ttm) 875 { 876 struct ttm_mem_global *mem_glob = ttm->glob->mem_glob; 877 unsigned i; 878 int ret; 879 880 if (ttm->state != tt_unpopulated) 881 return 0; 882 883 for (i = 0; i < ttm->num_pages; ++i) { 884 ret = ttm_get_pages(&ttm->pages[i], 1, 885 ttm->page_flags, 886 ttm->caching_state); 887 if (ret != 0) { 888 ttm_pool_unpopulate(ttm); 889 return -ENOMEM; 890 } 891 892 ret = ttm_mem_global_alloc_page(mem_glob, ttm->pages[i], 893 false, false); 894 if (unlikely(ret != 0)) { 895 ttm_pool_unpopulate(ttm); 896 return -ENOMEM; 897 } 898 } 899 900 if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { 901 ret = ttm_tt_swapin(ttm); 902 if (unlikely(ret != 0)) { 903 ttm_pool_unpopulate(ttm); 904 return ret; 905 } 906 } 907 908 ttm->state = tt_unbound; 909 return 0; 910 } 911 EXPORT_SYMBOL(ttm_pool_populate); 912 913 void ttm_pool_unpopulate(struct ttm_tt *ttm) 914 { 915 unsigned i; 916 917 for (i = 0; i < ttm->num_pages; ++i) { 918 if (ttm->pages[i]) { 919 ttm_mem_global_free_page(ttm->glob->mem_glob, 920 ttm->pages[i]); 921 ttm_put_pages(&ttm->pages[i], 1, 922 ttm->page_flags, 923 ttm->caching_state); 924 } 925 } 926 ttm->state = tt_unpopulated; 927 } 928 EXPORT_SYMBOL(ttm_pool_unpopulate); 929 930 #if 0 931 int ttm_page_alloc_debugfs(struct seq_file *m, void *data) 932 { 933 struct ttm_page_pool *p; 934 unsigned i; 935 char *h[] = {"pool", "refills", "pages freed", "size"}; 936 if (!_manager) { 937 seq_printf(m, "No pool allocator running.\n"); 938 return 0; 939 } 940 seq_printf(m, "%6s %12s %13s %8s\n", 941 h[0], h[1], h[2], h[3]); 942 for (i = 0; i < NUM_POOLS; ++i) { 943 p = &_manager->pools[i]; 944 945 seq_printf(m, "%6s %12ld %13ld %8d\n", 946 p->name, p->nrefills, 947 p->nfrees, p->npages); 948 } 949 return 0; 950 } 951 #endif 952 EXPORT_SYMBOL(ttm_page_alloc_debugfs); 953