1/* 2 * Copyright 2011 (c) Oracle Corp. 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 * Author: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> 24 */ 25 26/* 27 * A simple DMA pool losely based on dmapool.c. It has certain advantages 28 * over the DMA pools: 29 * - Pool collects resently freed pages for reuse (and hooks up to 30 * the shrinker). 31 * - Tracks currently in use pages 32 * - Tracks whether the page is UC, WB or cached (and reverts to WB 33 * when freed). 34 */ 35 36#if defined(CONFIG_SWIOTLB) || defined(CONFIG_INTEL_IOMMU) 37#define pr_fmt(fmt) "[TTM] " fmt 38 39#include <linux/dma-mapping.h> 40#include <linux/list.h> 41#include <linux/seq_file.h> /* for seq_printf */ 42#include <linux/slab.h> 43#include <linux/spinlock.h> 44#include <linux/highmem.h> 45#include <linux/mm_types.h> 46#include <linux/module.h> 47#include <linux/mm.h> 48#include <linux/atomic.h> 49#include <linux/device.h> 50#include <linux/kthread.h> 51#include <drm/ttm/ttm_bo_driver.h> 52#include <drm/ttm/ttm_page_alloc.h> 53#ifdef TTM_HAS_AGP 54#include <asm/agp.h> 55#endif 56 57#define NUM_PAGES_TO_ALLOC (PAGE_SIZE/sizeof(struct page *)) 58#define SMALL_ALLOCATION 4 59#define FREE_ALL_PAGES (~0U) 60/* times are in msecs */ 61#define IS_UNDEFINED (0) 62#define IS_WC (1<<1) 63#define IS_UC (1<<2) 64#define IS_CACHED (1<<3) 65#define IS_DMA32 (1<<4) 66 67enum pool_type { 68 POOL_IS_UNDEFINED, 69 POOL_IS_WC = IS_WC, 70 POOL_IS_UC = IS_UC, 71 POOL_IS_CACHED = IS_CACHED, 72 POOL_IS_WC_DMA32 = IS_WC | IS_DMA32, 73 POOL_IS_UC_DMA32 = IS_UC | IS_DMA32, 74 POOL_IS_CACHED_DMA32 = IS_CACHED | IS_DMA32, 75}; 76/* 77 * The pool structure. There are usually six pools: 78 * - generic (not restricted to DMA32): 79 * - write combined, uncached, cached. 80 * - dma32 (up to 2^32 - so up 4GB): 81 * - write combined, uncached, cached. 82 * for each 'struct device'. The 'cached' is for pages that are actively used. 83 * The other ones can be shrunk by the shrinker API if neccessary. 84 * @pools: The 'struct device->dma_pools' link. 85 * @type: Type of the pool 86 * @lock: Protects the inuse_list and free_list from concurrnet access. Must be 87 * used with irqsave/irqrestore variants because pool allocator maybe called 88 * from delayed work. 89 * @inuse_list: Pool of pages that are in use. The order is very important and 90 * it is in the order that the TTM pages that are put back are in. 91 * @free_list: Pool of pages that are free to be used. No order requirements. 92 * @dev: The device that is associated with these pools. 93 * @size: Size used during DMA allocation. 94 * @npages_free: Count of available pages for re-use. 95 * @npages_in_use: Count of pages that are in use. 96 * @nfrees: Stats when pool is shrinking. 97 * @nrefills: Stats when the pool is grown. 98 * @gfp_flags: Flags to pass for alloc_page. 99 * @name: Name of the pool. 100 * @dev_name: Name derieved from dev - similar to how dev_info works. 101 * Used during shutdown as the dev_info during release is unavailable. 102 */ 103struct dma_pool { 104 struct list_head pools; /* The 'struct device->dma_pools link */ 105 enum pool_type type; 106 spinlock_t lock; 107 struct list_head inuse_list; 108 struct list_head free_list; 109 struct device *dev; 110 unsigned size; 111 unsigned npages_free; 112 unsigned npages_in_use; 113 unsigned long nfrees; /* Stats when shrunk. */ 114 unsigned long nrefills; /* Stats when grown. */ 115 gfp_t gfp_flags; 116 char name[13]; /* "cached dma32" */ 117 char dev_name[64]; /* Constructed from dev */ 118}; 119 120/* 121 * The accounting page keeping track of the allocated page along with 122 * the DMA address. 123 * @page_list: The link to the 'page_list' in 'struct dma_pool'. 124 * @vaddr: The virtual address of the page 125 * @dma: The bus address of the page. If the page is not allocated 126 * via the DMA API, it will be -1. 127 */ 128struct dma_page { 129 struct list_head page_list; 130 void *vaddr; 131 struct page *p; 132 dma_addr_t dma; 133}; 134 135/* 136 * Limits for the pool. They are handled without locks because only place where 137 * they may change is in sysfs store. They won't have immediate effect anyway 138 * so forcing serialization to access them is pointless. 139 */ 140 141struct ttm_pool_opts { 142 unsigned alloc_size; 143 unsigned max_size; 144 unsigned small; 145}; 146 147/* 148 * Contains the list of all of the 'struct device' and their corresponding 149 * DMA pools. Guarded by _mutex->lock. 150 * @pools: The link to 'struct ttm_pool_manager->pools' 151 * @dev: The 'struct device' associated with the 'pool' 152 * @pool: The 'struct dma_pool' associated with the 'dev' 153 */ 154struct device_pools { 155 struct list_head pools; 156 struct device *dev; 157 struct dma_pool *pool; 158}; 159 160/* 161 * struct ttm_pool_manager - Holds memory pools for fast allocation 162 * 163 * @lock: Lock used when adding/removing from pools 164 * @pools: List of 'struct device' and 'struct dma_pool' tuples. 165 * @options: Limits for the pool. 166 * @npools: Total amount of pools in existence. 167 * @shrinker: The structure used by [un|]register_shrinker 168 */ 169struct ttm_pool_manager { 170 struct mutex lock; 171 struct list_head pools; 172 struct ttm_pool_opts options; 173 unsigned npools; 174 struct shrinker mm_shrink; 175 struct kobject kobj; 176}; 177 178static struct ttm_pool_manager *_manager; 179 180static struct attribute ttm_page_pool_max = { 181 .name = "pool_max_size", 182 .mode = S_IRUGO | S_IWUSR 183}; 184static struct attribute ttm_page_pool_small = { 185 .name = "pool_small_allocation", 186 .mode = S_IRUGO | S_IWUSR 187}; 188static struct attribute ttm_page_pool_alloc_size = { 189 .name = "pool_allocation_size", 190 .mode = S_IRUGO | S_IWUSR 191}; 192 193static struct attribute *ttm_pool_attrs[] = { 194 &ttm_page_pool_max, 195 &ttm_page_pool_small, 196 &ttm_page_pool_alloc_size, 197 NULL 198}; 199 200static void ttm_pool_kobj_release(struct kobject *kobj) 201{ 202 struct ttm_pool_manager *m = 203 container_of(kobj, struct ttm_pool_manager, kobj); 204 kfree(m); 205} 206 207static ssize_t ttm_pool_store(struct kobject *kobj, struct attribute *attr, 208 const char *buffer, size_t size) 209{ 210 struct ttm_pool_manager *m = 211 container_of(kobj, struct ttm_pool_manager, kobj); 212 int chars; 213 unsigned val; 214 chars = sscanf(buffer, "%u", &val); 215 if (chars == 0) 216 return size; 217 218 /* Convert kb to number of pages */ 219 val = val / (PAGE_SIZE >> 10); 220 221 if (attr == &ttm_page_pool_max) 222 m->options.max_size = val; 223 else if (attr == &ttm_page_pool_small) 224 m->options.small = val; 225 else if (attr == &ttm_page_pool_alloc_size) { 226 if (val > NUM_PAGES_TO_ALLOC*8) { 227 pr_err("Setting allocation size to %lu is not allowed. Recommended size is %lu\n", 228 NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 7), 229 NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 10)); 230 return size; 231 } else if (val > NUM_PAGES_TO_ALLOC) { 232 pr_warn("Setting allocation size to larger than %lu is not recommended\n", 233 NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 10)); 234 } 235 m->options.alloc_size = val; 236 } 237 238 return size; 239} 240 241static ssize_t ttm_pool_show(struct kobject *kobj, struct attribute *attr, 242 char *buffer) 243{ 244 struct ttm_pool_manager *m = 245 container_of(kobj, struct ttm_pool_manager, kobj); 246 unsigned val = 0; 247 248 if (attr == &ttm_page_pool_max) 249 val = m->options.max_size; 250 else if (attr == &ttm_page_pool_small) 251 val = m->options.small; 252 else if (attr == &ttm_page_pool_alloc_size) 253 val = m->options.alloc_size; 254 255 val = val * (PAGE_SIZE >> 10); 256 257 return snprintf(buffer, PAGE_SIZE, "%u\n", val); 258} 259 260static const struct sysfs_ops ttm_pool_sysfs_ops = { 261 .show = &ttm_pool_show, 262 .store = &ttm_pool_store, 263}; 264 265static struct kobj_type ttm_pool_kobj_type = { 266 .release = &ttm_pool_kobj_release, 267 .sysfs_ops = &ttm_pool_sysfs_ops, 268 .default_attrs = ttm_pool_attrs, 269}; 270 271#ifndef CONFIG_X86 272static int set_pages_array_wb(struct page **pages, int addrinarray) 273{ 274#ifdef TTM_HAS_AGP 275 int i; 276 277 for (i = 0; i < addrinarray; i++) 278 unmap_page_from_agp(pages[i]); 279#endif 280 return 0; 281} 282 283static int set_pages_array_wc(struct page **pages, int addrinarray) 284{ 285#ifdef TTM_HAS_AGP 286 int i; 287 288 for (i = 0; i < addrinarray; i++) 289 map_page_into_agp(pages[i]); 290#endif 291 return 0; 292} 293 294static int set_pages_array_uc(struct page **pages, int addrinarray) 295{ 296#ifdef TTM_HAS_AGP 297 int i; 298 299 for (i = 0; i < addrinarray; i++) 300 map_page_into_agp(pages[i]); 301#endif 302 return 0; 303} 304#endif /* for !CONFIG_X86 */ 305 306static int ttm_set_pages_caching(struct dma_pool *pool, 307 struct page **pages, unsigned cpages) 308{ 309 int r = 0; 310 /* Set page caching */ 311 if (pool->type & IS_UC) { 312 r = set_pages_array_uc(pages, cpages); 313 if (r) 314 pr_err("%s: Failed to set %d pages to uc!\n", 315 pool->dev_name, cpages); 316 } 317 if (pool->type & IS_WC) { 318 r = set_pages_array_wc(pages, cpages); 319 if (r) 320 pr_err("%s: Failed to set %d pages to wc!\n", 321 pool->dev_name, cpages); 322 } 323 return r; 324} 325 326static void __ttm_dma_free_page(struct dma_pool *pool, struct dma_page *d_page) 327{ 328 dma_addr_t dma = d_page->dma; 329 dma_free_coherent(pool->dev, pool->size, d_page->vaddr, dma); 330 331 kfree(d_page); 332 d_page = NULL; 333} 334static struct dma_page *__ttm_dma_alloc_page(struct dma_pool *pool) 335{ 336 struct dma_page *d_page; 337 338 d_page = kmalloc(sizeof(struct dma_page), GFP_KERNEL); 339 if (!d_page) 340 return NULL; 341 342 d_page->vaddr = dma_alloc_coherent(pool->dev, pool->size, 343 &d_page->dma, 344 pool->gfp_flags); 345 if (d_page->vaddr) 346 d_page->p = virt_to_page(d_page->vaddr); 347 else { 348 kfree(d_page); 349 d_page = NULL; 350 } 351 return d_page; 352} 353static enum pool_type ttm_to_type(int flags, enum ttm_caching_state cstate) 354{ 355 enum pool_type type = IS_UNDEFINED; 356 357 if (flags & TTM_PAGE_FLAG_DMA32) 358 type |= IS_DMA32; 359 if (cstate == tt_cached) 360 type |= IS_CACHED; 361 else if (cstate == tt_uncached) 362 type |= IS_UC; 363 else 364 type |= IS_WC; 365 366 return type; 367} 368 369static void ttm_pool_update_free_locked(struct dma_pool *pool, 370 unsigned freed_pages) 371{ 372 pool->npages_free -= freed_pages; 373 pool->nfrees += freed_pages; 374 375} 376 377/* set memory back to wb and free the pages. */ 378static void ttm_dma_pages_put(struct dma_pool *pool, struct list_head *d_pages, 379 struct page *pages[], unsigned npages) 380{ 381 struct dma_page *d_page, *tmp; 382 383 /* Don't set WB on WB page pool. */ 384 if (npages && !(pool->type & IS_CACHED) && 385 set_pages_array_wb(pages, npages)) 386 pr_err("%s: Failed to set %d pages to wb!\n", 387 pool->dev_name, npages); 388 389 list_for_each_entry_safe(d_page, tmp, d_pages, page_list) { 390 list_del(&d_page->page_list); 391 __ttm_dma_free_page(pool, d_page); 392 } 393} 394 395static void ttm_dma_page_put(struct dma_pool *pool, struct dma_page *d_page) 396{ 397 /* Don't set WB on WB page pool. */ 398 if (!(pool->type & IS_CACHED) && set_pages_array_wb(&d_page->p, 1)) 399 pr_err("%s: Failed to set %d pages to wb!\n", 400 pool->dev_name, 1); 401 402 list_del(&d_page->page_list); 403 __ttm_dma_free_page(pool, d_page); 404} 405 406/* 407 * Free pages from pool. 408 * 409 * To prevent hogging the ttm_swap process we only free NUM_PAGES_TO_ALLOC 410 * number of pages in one go. 411 * 412 * @pool: to free the pages from 413 * @nr_free: If set to true will free all pages in pool 414 * @gfp: GFP flags. 415 **/ 416static unsigned ttm_dma_page_pool_free(struct dma_pool *pool, unsigned nr_free, 417 gfp_t gfp) 418{ 419 unsigned long irq_flags; 420 struct dma_page *dma_p, *tmp; 421 struct page **pages_to_free; 422 struct list_head d_pages; 423 unsigned freed_pages = 0, 424 npages_to_free = nr_free; 425 426 if (NUM_PAGES_TO_ALLOC < nr_free) 427 npages_to_free = NUM_PAGES_TO_ALLOC; 428#if 0 429 if (nr_free > 1) { 430 pr_debug("%s: (%s:%d) Attempting to free %d (%d) pages\n", 431 pool->dev_name, pool->name, current->pid, 432 npages_to_free, nr_free); 433 } 434#endif 435 pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), gfp); 436 437 if (!pages_to_free) { 438 pr_err("%s: Failed to allocate memory for pool free operation\n", 439 pool->dev_name); 440 return 0; 441 } 442 INIT_LIST_HEAD(&d_pages); 443restart: 444 spin_lock_irqsave(&pool->lock, irq_flags); 445 446 /* We picking the oldest ones off the list */ 447 list_for_each_entry_safe_reverse(dma_p, tmp, &pool->free_list, 448 page_list) { 449 if (freed_pages >= npages_to_free) 450 break; 451 452 /* Move the dma_page from one list to another. */ 453 list_move(&dma_p->page_list, &d_pages); 454 455 pages_to_free[freed_pages++] = dma_p->p; 456 /* We can only remove NUM_PAGES_TO_ALLOC at a time. */ 457 if (freed_pages >= NUM_PAGES_TO_ALLOC) { 458 459 ttm_pool_update_free_locked(pool, freed_pages); 460 /** 461 * Because changing page caching is costly 462 * we unlock the pool to prevent stalling. 463 */ 464 spin_unlock_irqrestore(&pool->lock, irq_flags); 465 466 ttm_dma_pages_put(pool, &d_pages, pages_to_free, 467 freed_pages); 468 469 INIT_LIST_HEAD(&d_pages); 470 471 if (likely(nr_free != FREE_ALL_PAGES)) 472 nr_free -= freed_pages; 473 474 if (NUM_PAGES_TO_ALLOC >= nr_free) 475 npages_to_free = nr_free; 476 else 477 npages_to_free = NUM_PAGES_TO_ALLOC; 478 479 freed_pages = 0; 480 481 /* free all so restart the processing */ 482 if (nr_free) 483 goto restart; 484 485 /* Not allowed to fall through or break because 486 * following context is inside spinlock while we are 487 * outside here. 488 */ 489 goto out; 490 491 } 492 } 493 494 /* remove range of pages from the pool */ 495 if (freed_pages) { 496 ttm_pool_update_free_locked(pool, freed_pages); 497 nr_free -= freed_pages; 498 } 499 500 spin_unlock_irqrestore(&pool->lock, irq_flags); 501 502 if (freed_pages) 503 ttm_dma_pages_put(pool, &d_pages, pages_to_free, freed_pages); 504out: 505 kfree(pages_to_free); 506 return nr_free; 507} 508 509static void ttm_dma_free_pool(struct device *dev, enum pool_type type) 510{ 511 struct device_pools *p; 512 struct dma_pool *pool; 513 514 if (!dev) 515 return; 516 517 mutex_lock(&_manager->lock); 518 list_for_each_entry_reverse(p, &_manager->pools, pools) { 519 if (p->dev != dev) 520 continue; 521 pool = p->pool; 522 if (pool->type != type) 523 continue; 524 525 list_del(&p->pools); 526 kfree(p); 527 _manager->npools--; 528 break; 529 } 530 list_for_each_entry_reverse(pool, &dev->dma_pools, pools) { 531 if (pool->type != type) 532 continue; 533 /* Takes a spinlock.. */ 534 ttm_dma_page_pool_free(pool, FREE_ALL_PAGES, GFP_KERNEL); 535 WARN_ON(((pool->npages_in_use + pool->npages_free) != 0)); 536 /* This code path is called after _all_ references to the 537 * struct device has been dropped - so nobody should be 538 * touching it. In case somebody is trying to _add_ we are 539 * guarded by the mutex. */ 540 list_del(&pool->pools); 541 kfree(pool); 542 break; 543 } 544 mutex_unlock(&_manager->lock); 545} 546 547/* 548 * On free-ing of the 'struct device' this deconstructor is run. 549 * Albeit the pool might have already been freed earlier. 550 */ 551static void ttm_dma_pool_release(struct device *dev, void *res) 552{ 553 struct dma_pool *pool = *(struct dma_pool **)res; 554 555 if (pool) 556 ttm_dma_free_pool(dev, pool->type); 557} 558 559static int ttm_dma_pool_match(struct device *dev, void *res, void *match_data) 560{ 561 return *(struct dma_pool **)res == match_data; 562} 563 564static struct dma_pool *ttm_dma_pool_init(struct device *dev, gfp_t flags, 565 enum pool_type type) 566{ 567 char *n[] = {"wc", "uc", "cached", " dma32", "unknown",}; 568 enum pool_type t[] = {IS_WC, IS_UC, IS_CACHED, IS_DMA32, IS_UNDEFINED}; 569 struct device_pools *sec_pool = NULL; 570 struct dma_pool *pool = NULL, **ptr; 571 unsigned i; 572 int ret = -ENODEV; 573 char *p; 574 575 if (!dev) 576 return NULL; 577 578 ptr = devres_alloc(ttm_dma_pool_release, sizeof(*ptr), GFP_KERNEL); 579 if (!ptr) 580 return NULL; 581 582 ret = -ENOMEM; 583 584 pool = kmalloc_node(sizeof(struct dma_pool), GFP_KERNEL, 585 dev_to_node(dev)); 586 if (!pool) 587 goto err_mem; 588 589 sec_pool = kmalloc_node(sizeof(struct device_pools), GFP_KERNEL, 590 dev_to_node(dev)); 591 if (!sec_pool) 592 goto err_mem; 593 594 INIT_LIST_HEAD(&sec_pool->pools); 595 sec_pool->dev = dev; 596 sec_pool->pool = pool; 597 598 INIT_LIST_HEAD(&pool->free_list); 599 INIT_LIST_HEAD(&pool->inuse_list); 600 INIT_LIST_HEAD(&pool->pools); 601 spin_lock_init(&pool->lock); 602 pool->dev = dev; 603 pool->npages_free = pool->npages_in_use = 0; 604 pool->nfrees = 0; 605 pool->gfp_flags = flags; 606 pool->size = PAGE_SIZE; 607 pool->type = type; 608 pool->nrefills = 0; 609 p = pool->name; 610 for (i = 0; i < 5; i++) { 611 if (type & t[i]) { 612 p += snprintf(p, sizeof(pool->name) - (p - pool->name), 613 "%s", n[i]); 614 } 615 } 616 *p = 0; 617 /* We copy the name for pr_ calls b/c when dma_pool_destroy is called 618 * - the kobj->name has already been deallocated.*/ 619 snprintf(pool->dev_name, sizeof(pool->dev_name), "%s %s", 620 dev_driver_string(dev), dev_name(dev)); 621 mutex_lock(&_manager->lock); 622 /* You can get the dma_pool from either the global: */ 623 list_add(&sec_pool->pools, &_manager->pools); 624 _manager->npools++; 625 /* or from 'struct device': */ 626 list_add(&pool->pools, &dev->dma_pools); 627 mutex_unlock(&_manager->lock); 628 629 *ptr = pool; 630 devres_add(dev, ptr); 631 632 return pool; 633err_mem: 634 devres_free(ptr); 635 kfree(sec_pool); 636 kfree(pool); 637 return ERR_PTR(ret); 638} 639 640static struct dma_pool *ttm_dma_find_pool(struct device *dev, 641 enum pool_type type) 642{ 643 struct dma_pool *pool, *tmp, *found = NULL; 644 645 if (type == IS_UNDEFINED) 646 return found; 647 648 /* NB: We iterate on the 'struct dev' which has no spinlock, but 649 * it does have a kref which we have taken. The kref is taken during 650 * graphic driver loading - in the drm_pci_init it calls either 651 * pci_dev_get or pci_register_driver which both end up taking a kref 652 * on 'struct device'. 653 * 654 * On teardown, the graphic drivers end up quiescing the TTM (put_pages) 655 * and calls the dev_res deconstructors: ttm_dma_pool_release. The nice 656 * thing is at that point of time there are no pages associated with the 657 * driver so this function will not be called. 658 */ 659 list_for_each_entry_safe(pool, tmp, &dev->dma_pools, pools) { 660 if (pool->type != type) 661 continue; 662 found = pool; 663 break; 664 } 665 return found; 666} 667 668/* 669 * Free pages the pages that failed to change the caching state. If there 670 * are pages that have changed their caching state already put them to the 671 * pool. 672 */ 673static void ttm_dma_handle_caching_state_failure(struct dma_pool *pool, 674 struct list_head *d_pages, 675 struct page **failed_pages, 676 unsigned cpages) 677{ 678 struct dma_page *d_page, *tmp; 679 struct page *p; 680 unsigned i = 0; 681 682 p = failed_pages[0]; 683 if (!p) 684 return; 685 /* Find the failed page. */ 686 list_for_each_entry_safe(d_page, tmp, d_pages, page_list) { 687 if (d_page->p != p) 688 continue; 689 /* .. and then progress over the full list. */ 690 list_del(&d_page->page_list); 691 __ttm_dma_free_page(pool, d_page); 692 if (++i < cpages) 693 p = failed_pages[i]; 694 else 695 break; 696 } 697 698} 699 700/* 701 * Allocate 'count' pages, and put 'need' number of them on the 702 * 'pages' and as well on the 'dma_address' starting at 'dma_offset' offset. 703 * The full list of pages should also be on 'd_pages'. 704 * We return zero for success, and negative numbers as errors. 705 */ 706static int ttm_dma_pool_alloc_new_pages(struct dma_pool *pool, 707 struct list_head *d_pages, 708 unsigned count) 709{ 710 struct page **caching_array; 711 struct dma_page *dma_p; 712 struct page *p; 713 int r = 0; 714 unsigned i, cpages; 715 unsigned max_cpages = min(count, 716 (unsigned)(PAGE_SIZE/sizeof(struct page *))); 717 718 /* allocate array for page caching change */ 719 caching_array = kmalloc(max_cpages*sizeof(struct page *), GFP_KERNEL); 720 721 if (!caching_array) { 722 pr_err("%s: Unable to allocate table for new pages\n", 723 pool->dev_name); 724 return -ENOMEM; 725 } 726 727 if (count > 1) { 728 pr_debug("%s: (%s:%d) Getting %d pages\n", 729 pool->dev_name, pool->name, current->pid, count); 730 } 731 732 for (i = 0, cpages = 0; i < count; ++i) { 733 dma_p = __ttm_dma_alloc_page(pool); 734 if (!dma_p) { 735 pr_err("%s: Unable to get page %u\n", 736 pool->dev_name, i); 737 738 /* store already allocated pages in the pool after 739 * setting the caching state */ 740 if (cpages) { 741 r = ttm_set_pages_caching(pool, caching_array, 742 cpages); 743 if (r) 744 ttm_dma_handle_caching_state_failure( 745 pool, d_pages, caching_array, 746 cpages); 747 } 748 r = -ENOMEM; 749 goto out; 750 } 751 p = dma_p->p; 752#ifdef CONFIG_HIGHMEM 753 /* gfp flags of highmem page should never be dma32 so we 754 * we should be fine in such case 755 */ 756 if (!PageHighMem(p)) 757#endif 758 { 759 caching_array[cpages++] = p; 760 if (cpages == max_cpages) { 761 /* Note: Cannot hold the spinlock */ 762 r = ttm_set_pages_caching(pool, caching_array, 763 cpages); 764 if (r) { 765 ttm_dma_handle_caching_state_failure( 766 pool, d_pages, caching_array, 767 cpages); 768 goto out; 769 } 770 cpages = 0; 771 } 772 } 773 list_add(&dma_p->page_list, d_pages); 774 } 775 776 if (cpages) { 777 r = ttm_set_pages_caching(pool, caching_array, cpages); 778 if (r) 779 ttm_dma_handle_caching_state_failure(pool, d_pages, 780 caching_array, cpages); 781 } 782out: 783 kfree(caching_array); 784 return r; 785} 786 787/* 788 * @return count of pages still required to fulfill the request. 789 */ 790static int ttm_dma_page_pool_fill_locked(struct dma_pool *pool, 791 unsigned long *irq_flags) 792{ 793 unsigned count = _manager->options.small; 794 int r = pool->npages_free; 795 796 if (count > pool->npages_free) { 797 struct list_head d_pages; 798 799 INIT_LIST_HEAD(&d_pages); 800 801 spin_unlock_irqrestore(&pool->lock, *irq_flags); 802 803 /* Returns how many more are neccessary to fulfill the 804 * request. */ 805 r = ttm_dma_pool_alloc_new_pages(pool, &d_pages, count); 806 807 spin_lock_irqsave(&pool->lock, *irq_flags); 808 if (!r) { 809 /* Add the fresh to the end.. */ 810 list_splice(&d_pages, &pool->free_list); 811 ++pool->nrefills; 812 pool->npages_free += count; 813 r = count; 814 } else { 815 struct dma_page *d_page; 816 unsigned cpages = 0; 817 818 pr_err("%s: Failed to fill %s pool (r:%d)!\n", 819 pool->dev_name, pool->name, r); 820 821 list_for_each_entry(d_page, &d_pages, page_list) { 822 cpages++; 823 } 824 list_splice_tail(&d_pages, &pool->free_list); 825 pool->npages_free += cpages; 826 r = cpages; 827 } 828 } 829 return r; 830} 831 832/* 833 * @return count of pages still required to fulfill the request. 834 * The populate list is actually a stack (not that is matters as TTM 835 * allocates one page at a time. 836 */ 837static int ttm_dma_pool_get_pages(struct dma_pool *pool, 838 struct ttm_dma_tt *ttm_dma, 839 unsigned index) 840{ 841 struct dma_page *d_page; 842 struct ttm_tt *ttm = &ttm_dma->ttm; 843 unsigned long irq_flags; 844 int count, r = -ENOMEM; 845 846 spin_lock_irqsave(&pool->lock, irq_flags); 847 count = ttm_dma_page_pool_fill_locked(pool, &irq_flags); 848 if (count) { 849 d_page = list_first_entry(&pool->free_list, struct dma_page, page_list); 850 ttm->pages[index] = d_page->p; 851 ttm_dma->cpu_address[index] = d_page->vaddr; 852 ttm_dma->dma_address[index] = d_page->dma; 853 list_move_tail(&d_page->page_list, &ttm_dma->pages_list); 854 r = 0; 855 pool->npages_in_use += 1; 856 pool->npages_free -= 1; 857 } 858 spin_unlock_irqrestore(&pool->lock, irq_flags); 859 return r; 860} 861 862/* 863 * On success pages list will hold count number of correctly 864 * cached pages. On failure will hold the negative return value (-ENOMEM, etc). 865 */ 866int ttm_dma_populate(struct ttm_dma_tt *ttm_dma, struct device *dev) 867{ 868 struct ttm_tt *ttm = &ttm_dma->ttm; 869 struct ttm_mem_global *mem_glob = ttm->glob->mem_glob; 870 struct dma_pool *pool; 871 enum pool_type type; 872 unsigned i; 873 gfp_t gfp_flags; 874 int ret; 875 876 if (ttm->state != tt_unpopulated) 877 return 0; 878 879 type = ttm_to_type(ttm->page_flags, ttm->caching_state); 880 if (ttm->page_flags & TTM_PAGE_FLAG_DMA32) 881 gfp_flags = GFP_USER | GFP_DMA32; 882 else 883 gfp_flags = GFP_HIGHUSER; 884 if (ttm->page_flags & TTM_PAGE_FLAG_ZERO_ALLOC) 885 gfp_flags |= __GFP_ZERO; 886 887 pool = ttm_dma_find_pool(dev, type); 888 if (!pool) { 889 pool = ttm_dma_pool_init(dev, gfp_flags, type); 890 if (IS_ERR_OR_NULL(pool)) { 891 return -ENOMEM; 892 } 893 } 894 895 INIT_LIST_HEAD(&ttm_dma->pages_list); 896 for (i = 0; i < ttm->num_pages; ++i) { 897 ret = ttm_dma_pool_get_pages(pool, ttm_dma, i); 898 if (ret != 0) { 899 ttm_dma_unpopulate(ttm_dma, dev); 900 return -ENOMEM; 901 } 902 903 ret = ttm_mem_global_alloc_page(mem_glob, ttm->pages[i], 904 false, false); 905 if (unlikely(ret != 0)) { 906 ttm_dma_unpopulate(ttm_dma, dev); 907 return -ENOMEM; 908 } 909 } 910 911 if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { 912 ret = ttm_tt_swapin(ttm); 913 if (unlikely(ret != 0)) { 914 ttm_dma_unpopulate(ttm_dma, dev); 915 return ret; 916 } 917 } 918 919 ttm->state = tt_unbound; 920 return 0; 921} 922EXPORT_SYMBOL_GPL(ttm_dma_populate); 923 924/* Put all pages in pages list to correct pool to wait for reuse */ 925void ttm_dma_unpopulate(struct ttm_dma_tt *ttm_dma, struct device *dev) 926{ 927 struct ttm_tt *ttm = &ttm_dma->ttm; 928 struct dma_pool *pool; 929 struct dma_page *d_page, *next; 930 enum pool_type type; 931 bool is_cached = false; 932 unsigned count = 0, i, npages = 0; 933 unsigned long irq_flags; 934 935 type = ttm_to_type(ttm->page_flags, ttm->caching_state); 936 pool = ttm_dma_find_pool(dev, type); 937 if (!pool) 938 return; 939 940 is_cached = (ttm_dma_find_pool(pool->dev, 941 ttm_to_type(ttm->page_flags, tt_cached)) == pool); 942 943 /* make sure pages array match list and count number of pages */ 944 list_for_each_entry(d_page, &ttm_dma->pages_list, page_list) { 945 ttm->pages[count] = d_page->p; 946 count++; 947 } 948 949 spin_lock_irqsave(&pool->lock, irq_flags); 950 pool->npages_in_use -= count; 951 if (is_cached) { 952 pool->nfrees += count; 953 } else { 954 pool->npages_free += count; 955 list_splice(&ttm_dma->pages_list, &pool->free_list); 956 npages = count; 957 if (pool->npages_free > _manager->options.max_size) { 958 npages = pool->npages_free - _manager->options.max_size; 959 /* free at least NUM_PAGES_TO_ALLOC number of pages 960 * to reduce calls to set_memory_wb */ 961 if (npages < NUM_PAGES_TO_ALLOC) 962 npages = NUM_PAGES_TO_ALLOC; 963 } 964 } 965 spin_unlock_irqrestore(&pool->lock, irq_flags); 966 967 if (is_cached) { 968 list_for_each_entry_safe(d_page, next, &ttm_dma->pages_list, page_list) { 969 ttm_mem_global_free_page(ttm->glob->mem_glob, 970 d_page->p); 971 ttm_dma_page_put(pool, d_page); 972 } 973 } else { 974 for (i = 0; i < count; i++) { 975 ttm_mem_global_free_page(ttm->glob->mem_glob, 976 ttm->pages[i]); 977 } 978 } 979 980 INIT_LIST_HEAD(&ttm_dma->pages_list); 981 for (i = 0; i < ttm->num_pages; i++) { 982 ttm->pages[i] = NULL; 983 ttm_dma->cpu_address[i] = 0; 984 ttm_dma->dma_address[i] = 0; 985 } 986 987 /* shrink pool if necessary (only on !is_cached pools)*/ 988 if (npages) 989 ttm_dma_page_pool_free(pool, npages, GFP_KERNEL); 990 ttm->state = tt_unpopulated; 991} 992EXPORT_SYMBOL_GPL(ttm_dma_unpopulate); 993 994/** 995 * Callback for mm to request pool to reduce number of page held. 996 * 997 * XXX: (dchinner) Deadlock warning! 998 * 999 * We need to pass sc->gfp_mask to ttm_dma_page_pool_free(). 1000 * 1001 * I'm getting sadder as I hear more pathetical whimpers about needing per-pool 1002 * shrinkers 1003 */ 1004static unsigned long 1005ttm_dma_pool_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) 1006{ 1007 static unsigned start_pool; 1008 unsigned idx = 0; 1009 unsigned pool_offset; 1010 unsigned shrink_pages = sc->nr_to_scan; 1011 struct device_pools *p; 1012 unsigned long freed = 0; 1013 1014 if (list_empty(&_manager->pools)) 1015 return SHRINK_STOP; 1016 1017 if (!mutex_trylock(&_manager->lock)) 1018 return SHRINK_STOP; 1019 if (!_manager->npools) 1020 goto out; 1021 pool_offset = ++start_pool % _manager->npools; 1022 list_for_each_entry(p, &_manager->pools, pools) { 1023 unsigned nr_free; 1024 1025 if (!p->dev) 1026 continue; 1027 if (shrink_pages == 0) 1028 break; 1029 /* Do it in round-robin fashion. */ 1030 if (++idx < pool_offset) 1031 continue; 1032 nr_free = shrink_pages; 1033 shrink_pages = ttm_dma_page_pool_free(p->pool, nr_free, 1034 sc->gfp_mask); 1035 freed += nr_free - shrink_pages; 1036 1037 pr_debug("%s: (%s:%d) Asked to shrink %d, have %d more to go\n", 1038 p->pool->dev_name, p->pool->name, current->pid, 1039 nr_free, shrink_pages); 1040 } 1041out: 1042 mutex_unlock(&_manager->lock); 1043 return freed; 1044} 1045 1046static unsigned long 1047ttm_dma_pool_shrink_count(struct shrinker *shrink, struct shrink_control *sc) 1048{ 1049 struct device_pools *p; 1050 unsigned long count = 0; 1051 1052 if (!mutex_trylock(&_manager->lock)) 1053 return 0; 1054 list_for_each_entry(p, &_manager->pools, pools) 1055 count += p->pool->npages_free; 1056 mutex_unlock(&_manager->lock); 1057 return count; 1058} 1059 1060static void ttm_dma_pool_mm_shrink_init(struct ttm_pool_manager *manager) 1061{ 1062 manager->mm_shrink.count_objects = ttm_dma_pool_shrink_count; 1063 manager->mm_shrink.scan_objects = &ttm_dma_pool_shrink_scan; 1064 manager->mm_shrink.seeks = 1; 1065 register_shrinker(&manager->mm_shrink); 1066} 1067 1068static void ttm_dma_pool_mm_shrink_fini(struct ttm_pool_manager *manager) 1069{ 1070 unregister_shrinker(&manager->mm_shrink); 1071} 1072 1073int ttm_dma_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages) 1074{ 1075 int ret = -ENOMEM; 1076 1077 WARN_ON(_manager); 1078 1079 pr_info("Initializing DMA pool allocator\n"); 1080 1081 _manager = kzalloc(sizeof(*_manager), GFP_KERNEL); 1082 if (!_manager) 1083 goto err; 1084 1085 mutex_init(&_manager->lock); 1086 INIT_LIST_HEAD(&_manager->pools); 1087 1088 _manager->options.max_size = max_pages; 1089 _manager->options.small = SMALL_ALLOCATION; 1090 _manager->options.alloc_size = NUM_PAGES_TO_ALLOC; 1091 1092 /* This takes care of auto-freeing the _manager */ 1093 ret = kobject_init_and_add(&_manager->kobj, &ttm_pool_kobj_type, 1094 &glob->kobj, "dma_pool"); 1095 if (unlikely(ret != 0)) { 1096 kobject_put(&_manager->kobj); 1097 goto err; 1098 } 1099 ttm_dma_pool_mm_shrink_init(_manager); 1100 return 0; 1101err: 1102 return ret; 1103} 1104 1105void ttm_dma_page_alloc_fini(void) 1106{ 1107 struct device_pools *p, *t; 1108 1109 pr_info("Finalizing DMA pool allocator\n"); 1110 ttm_dma_pool_mm_shrink_fini(_manager); 1111 1112 list_for_each_entry_safe_reverse(p, t, &_manager->pools, pools) { 1113 dev_dbg(p->dev, "(%s:%d) Freeing.\n", p->pool->name, 1114 current->pid); 1115 WARN_ON(devres_destroy(p->dev, ttm_dma_pool_release, 1116 ttm_dma_pool_match, p->pool)); 1117 ttm_dma_free_pool(p->dev, p->pool->type); 1118 } 1119 kobject_put(&_manager->kobj); 1120 _manager = NULL; 1121} 1122 1123int ttm_dma_page_alloc_debugfs(struct seq_file *m, void *data) 1124{ 1125 struct device_pools *p; 1126 struct dma_pool *pool = NULL; 1127 char *h[] = {"pool", "refills", "pages freed", "inuse", "available", 1128 "name", "virt", "busaddr"}; 1129 1130 if (!_manager) { 1131 seq_printf(m, "No pool allocator running.\n"); 1132 return 0; 1133 } 1134 seq_printf(m, "%13s %12s %13s %8s %8s %8s\n", 1135 h[0], h[1], h[2], h[3], h[4], h[5]); 1136 mutex_lock(&_manager->lock); 1137 list_for_each_entry(p, &_manager->pools, pools) { 1138 struct device *dev = p->dev; 1139 if (!dev) 1140 continue; 1141 pool = p->pool; 1142 seq_printf(m, "%13s %12ld %13ld %8d %8d %8s\n", 1143 pool->name, pool->nrefills, 1144 pool->nfrees, pool->npages_in_use, 1145 pool->npages_free, 1146 pool->dev_name); 1147 } 1148 mutex_unlock(&_manager->lock); 1149 return 0; 1150} 1151EXPORT_SYMBOL_GPL(ttm_dma_page_alloc_debugfs); 1152 1153#endif 1154