diff options
Diffstat (limited to 'drivers/gpu/drm/ttm/ttm_page_alloc_dma.c')
| -rw-r--r-- | drivers/gpu/drm/ttm/ttm_page_alloc_dma.c | 1147 |
1 files changed, 1147 insertions, 0 deletions
diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c new file mode 100644 index 00000000000..fb8259f6983 --- /dev/null +++ b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c @@ -0,0 +1,1147 @@ +/* + * Copyright 2011 (c) Oracle Corp. + + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sub license, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + * + * Author: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> + */ + +/* + * A simple DMA pool losely based on dmapool.c. It has certain advantages + * over the DMA pools: + * - Pool collects resently freed pages for reuse (and hooks up to + * the shrinker). + * - Tracks currently in use pages + * - Tracks whether the page is UC, WB or cached (and reverts to WB + * when freed). + */ + +#if defined(CONFIG_SWIOTLB) || defined(CONFIG_INTEL_IOMMU) +#define pr_fmt(fmt) "[TTM] " fmt + +#include <linux/dma-mapping.h> +#include <linux/list.h> +#include <linux/seq_file.h> /* for seq_printf */ +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/highmem.h> +#include <linux/mm_types.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/atomic.h> +#include <linux/device.h> +#include <linux/kthread.h> +#include <drm/ttm/ttm_bo_driver.h> +#include <drm/ttm/ttm_page_alloc.h> +#ifdef TTM_HAS_AGP +#include <asm/agp.h> +#endif + +#define NUM_PAGES_TO_ALLOC (PAGE_SIZE/sizeof(struct page *)) +#define SMALL_ALLOCATION 4 +#define FREE_ALL_PAGES (~0U) +/* times are in msecs */ +#define IS_UNDEFINED (0) +#define IS_WC (1<<1) +#define IS_UC (1<<2) +#define IS_CACHED (1<<3) +#define IS_DMA32 (1<<4) + +enum pool_type { + POOL_IS_UNDEFINED, + POOL_IS_WC = IS_WC, + POOL_IS_UC = IS_UC, + POOL_IS_CACHED = IS_CACHED, + POOL_IS_WC_DMA32 = IS_WC | IS_DMA32, + POOL_IS_UC_DMA32 = IS_UC | IS_DMA32, + POOL_IS_CACHED_DMA32 = IS_CACHED | IS_DMA32, +}; +/* + * The pool structure. There are usually six pools: + * - generic (not restricted to DMA32): + * - write combined, uncached, cached. + * - dma32 (up to 2^32 - so up 4GB): + * - write combined, uncached, cached. + * for each 'struct device'. The 'cached' is for pages that are actively used. + * The other ones can be shrunk by the shrinker API if neccessary. + * @pools: The 'struct device->dma_pools' link. + * @type: Type of the pool + * @lock: Protects the inuse_list and free_list from concurrnet access. Must be + * used with irqsave/irqrestore variants because pool allocator maybe called + * from delayed work. + * @inuse_list: Pool of pages that are in use. The order is very important and + * it is in the order that the TTM pages that are put back are in. + * @free_list: Pool of pages that are free to be used. No order requirements. + * @dev: The device that is associated with these pools. + * @size: Size used during DMA allocation. + * @npages_free: Count of available pages for re-use. + * @npages_in_use: Count of pages that are in use. + * @nfrees: Stats when pool is shrinking. + * @nrefills: Stats when the pool is grown. + * @gfp_flags: Flags to pass for alloc_page. + * @name: Name of the pool. + * @dev_name: Name derieved from dev - similar to how dev_info works. + * Used during shutdown as the dev_info during release is unavailable. + */ +struct dma_pool { + struct list_head pools; /* The 'struct device->dma_pools link */ + enum pool_type type; + spinlock_t lock; + struct list_head inuse_list; + struct list_head free_list; + struct device *dev; + unsigned size; + unsigned npages_free; + unsigned npages_in_use; + unsigned long nfrees; /* Stats when shrunk. */ + unsigned long nrefills; /* Stats when grown. */ + gfp_t gfp_flags; + char name[13]; /* "cached dma32" */ + char dev_name[64]; /* Constructed from dev */ +}; + +/* + * The accounting page keeping track of the allocated page along with + * the DMA address. + * @page_list: The link to the 'page_list' in 'struct dma_pool'. + * @vaddr: The virtual address of the page + * @dma: The bus address of the page. If the page is not allocated + * via the DMA API, it will be -1. + */ +struct dma_page { + struct list_head page_list; + void *vaddr; + struct page *p; + dma_addr_t dma; +}; + +/* + * Limits for the pool. They are handled without locks because only place where + * they may change is in sysfs store. They won't have immediate effect anyway + * so forcing serialization to access them is pointless. + */ + +struct ttm_pool_opts { + unsigned alloc_size; + unsigned max_size; + unsigned small; +}; + +/* + * Contains the list of all of the 'struct device' and their corresponding + * DMA pools. Guarded by _mutex->lock. + * @pools: The link to 'struct ttm_pool_manager->pools' + * @dev: The 'struct device' associated with the 'pool' + * @pool: The 'struct dma_pool' associated with the 'dev' + */ +struct device_pools { + struct list_head pools; + struct device *dev; + struct dma_pool *pool; +}; + +/* + * struct ttm_pool_manager - Holds memory pools for fast allocation + * + * @lock: Lock used when adding/removing from pools + * @pools: List of 'struct device' and 'struct dma_pool' tuples. + * @options: Limits for the pool. + * @npools: Total amount of pools in existence. + * @shrinker: The structure used by [un|]register_shrinker + */ +struct ttm_pool_manager { + struct mutex lock; + struct list_head pools; + struct ttm_pool_opts options; + unsigned npools; + struct shrinker mm_shrink; + struct kobject kobj; +}; + +static struct ttm_pool_manager *_manager; + +static struct attribute ttm_page_pool_max = { + .name = "pool_max_size", + .mode = S_IRUGO | S_IWUSR +}; +static struct attribute ttm_page_pool_small = { + .name = "pool_small_allocation", + .mode = S_IRUGO | S_IWUSR +}; +static struct attribute ttm_page_pool_alloc_size = { + .name = "pool_allocation_size", + .mode = S_IRUGO | S_IWUSR +}; + +static struct attribute *ttm_pool_attrs[] = { + &ttm_page_pool_max, + &ttm_page_pool_small, + &ttm_page_pool_alloc_size, + NULL +}; + +static void ttm_pool_kobj_release(struct kobject *kobj) +{ + struct ttm_pool_manager *m = + container_of(kobj, struct ttm_pool_manager, kobj); + kfree(m); +} + +static ssize_t ttm_pool_store(struct kobject *kobj, struct attribute *attr, + const char *buffer, size_t size) +{ + struct ttm_pool_manager *m = + container_of(kobj, struct ttm_pool_manager, kobj); + int chars; + unsigned val; + chars = sscanf(buffer, "%u", &val); + if (chars == 0) + return size; + + /* Convert kb to number of pages */ + val = val / (PAGE_SIZE >> 10); + + if (attr == &ttm_page_pool_max) + m->options.max_size = val; + else if (attr == &ttm_page_pool_small) + m->options.small = val; + else if (attr == &ttm_page_pool_alloc_size) { + if (val > NUM_PAGES_TO_ALLOC*8) { + pr_err("Setting allocation size to %lu is not allowed. Recommended size is %lu\n", + NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 7), + NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 10)); + return size; + } else if (val > NUM_PAGES_TO_ALLOC) { + pr_warn("Setting allocation size to larger than %lu is not recommended\n", + NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 10)); + } + m->options.alloc_size = val; + } + + return size; +} + +static ssize_t ttm_pool_show(struct kobject *kobj, struct attribute *attr, + char *buffer) +{ + struct ttm_pool_manager *m = + container_of(kobj, struct ttm_pool_manager, kobj); + unsigned val = 0; + + if (attr == &ttm_page_pool_max) + val = m->options.max_size; + else if (attr == &ttm_page_pool_small) + val = m->options.small; + else if (attr == &ttm_page_pool_alloc_size) + val = m->options.alloc_size; + + val = val * (PAGE_SIZE >> 10); + + return snprintf(buffer, PAGE_SIZE, "%u\n", val); +} + +static const struct sysfs_ops ttm_pool_sysfs_ops = { + .show = &ttm_pool_show, + .store = &ttm_pool_store, +}; + +static struct kobj_type ttm_pool_kobj_type = { + .release = &ttm_pool_kobj_release, + .sysfs_ops = &ttm_pool_sysfs_ops, + .default_attrs = ttm_pool_attrs, +}; + +#ifndef CONFIG_X86 +static int set_pages_array_wb(struct page **pages, int addrinarray) +{ +#ifdef TTM_HAS_AGP + int i; + + for (i = 0; i < addrinarray; i++) + unmap_page_from_agp(pages[i]); +#endif + return 0; +} + +static int set_pages_array_wc(struct page **pages, int addrinarray) +{ +#ifdef TTM_HAS_AGP + int i; + + for (i = 0; i < addrinarray; i++) + map_page_into_agp(pages[i]); +#endif + return 0; +} + +static int set_pages_array_uc(struct page **pages, int addrinarray) +{ +#ifdef TTM_HAS_AGP + int i; + + for (i = 0; i < addrinarray; i++) + map_page_into_agp(pages[i]); +#endif + return 0; +} +#endif /* for !CONFIG_X86 */ + +static int ttm_set_pages_caching(struct dma_pool *pool, + struct page **pages, unsigned cpages) +{ + int r = 0; + /* Set page caching */ + if (pool->type & IS_UC) { + r = set_pages_array_uc(pages, cpages); + if (r) + pr_err("%s: Failed to set %d pages to uc!\n", + pool->dev_name, cpages); + } + if (pool->type & IS_WC) { + r = set_pages_array_wc(pages, cpages); + if (r) + pr_err("%s: Failed to set %d pages to wc!\n", + pool->dev_name, cpages); + } + return r; +} + +static void __ttm_dma_free_page(struct dma_pool *pool, struct dma_page *d_page) +{ + dma_addr_t dma = d_page->dma; + dma_free_coherent(pool->dev, pool->size, d_page->vaddr, dma); + + kfree(d_page); + d_page = NULL; +} +static struct dma_page *__ttm_dma_alloc_page(struct dma_pool *pool) +{ + struct dma_page *d_page; + + d_page = kmalloc(sizeof(struct dma_page), GFP_KERNEL); + if (!d_page) + return NULL; + + d_page->vaddr = dma_alloc_coherent(pool->dev, pool->size, + &d_page->dma, + pool->gfp_flags); + if (d_page->vaddr) + d_page->p = virt_to_page(d_page->vaddr); + else { + kfree(d_page); + d_page = NULL; + } + return d_page; +} +static enum pool_type ttm_to_type(int flags, enum ttm_caching_state cstate) +{ + enum pool_type type = IS_UNDEFINED; + + if (flags & TTM_PAGE_FLAG_DMA32) + type |= IS_DMA32; + if (cstate == tt_cached) + type |= IS_CACHED; + else if (cstate == tt_uncached) + type |= IS_UC; + else + type |= IS_WC; + + return type; +} + +static void ttm_pool_update_free_locked(struct dma_pool *pool, + unsigned freed_pages) +{ + pool->npages_free -= freed_pages; + pool->nfrees += freed_pages; + +} + +/* set memory back to wb and free the pages. */ +static void ttm_dma_pages_put(struct dma_pool *pool, struct list_head *d_pages, + struct page *pages[], unsigned npages) +{ + struct dma_page *d_page, *tmp; + + /* Don't set WB on WB page pool. */ + if (npages && !(pool->type & IS_CACHED) && + set_pages_array_wb(pages, npages)) + pr_err("%s: Failed to set %d pages to wb!\n", + pool->dev_name, npages); + + list_for_each_entry_safe(d_page, tmp, d_pages, page_list) { + list_del(&d_page->page_list); + __ttm_dma_free_page(pool, d_page); + } +} + +static void ttm_dma_page_put(struct dma_pool *pool, struct dma_page *d_page) +{ + /* Don't set WB on WB page pool. */ + if (!(pool->type & IS_CACHED) && set_pages_array_wb(&d_page->p, 1)) + pr_err("%s: Failed to set %d pages to wb!\n", + pool->dev_name, 1); + + list_del(&d_page->page_list); + __ttm_dma_free_page(pool, d_page); +} + +/* + * Free pages from pool. + * + * To prevent hogging the ttm_swap process we only free NUM_PAGES_TO_ALLOC + * number of pages in one go. + * + * @pool: to free the pages from + * @nr_free: If set to true will free all pages in pool + **/ +static unsigned ttm_dma_page_pool_free(struct dma_pool *pool, unsigned nr_free) +{ + unsigned long irq_flags; + struct dma_page *dma_p, *tmp; + struct page **pages_to_free; + struct list_head d_pages; + unsigned freed_pages = 0, + npages_to_free = nr_free; + + if (NUM_PAGES_TO_ALLOC < nr_free) + npages_to_free = NUM_PAGES_TO_ALLOC; +#if 0 + if (nr_free > 1) { + pr_debug("%s: (%s:%d) Attempting to free %d (%d) pages\n", + pool->dev_name, pool->name, current->pid, + npages_to_free, nr_free); + } +#endif + pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), + GFP_KERNEL); + + if (!pages_to_free) { + pr_err("%s: Failed to allocate memory for pool free operation\n", + pool->dev_name); + return 0; + } + INIT_LIST_HEAD(&d_pages); +restart: + spin_lock_irqsave(&pool->lock, irq_flags); + + /* We picking the oldest ones off the list */ + list_for_each_entry_safe_reverse(dma_p, tmp, &pool->free_list, + page_list) { + if (freed_pages >= npages_to_free) + break; + + /* Move the dma_page from one list to another. */ + list_move(&dma_p->page_list, &d_pages); + + pages_to_free[freed_pages++] = dma_p->p; + /* We can only remove NUM_PAGES_TO_ALLOC at a time. */ + if (freed_pages >= NUM_PAGES_TO_ALLOC) { + + ttm_pool_update_free_locked(pool, freed_pages); + /** + * Because changing page caching is costly + * we unlock the pool to prevent stalling. + */ + spin_unlock_irqrestore(&pool->lock, irq_flags); + + ttm_dma_pages_put(pool, &d_pages, pages_to_free, + freed_pages); + + INIT_LIST_HEAD(&d_pages); + + if (likely(nr_free != FREE_ALL_PAGES)) + nr_free -= freed_pages; + + if (NUM_PAGES_TO_ALLOC >= nr_free) + npages_to_free = nr_free; + else + npages_to_free = NUM_PAGES_TO_ALLOC; + + freed_pages = 0; + + /* free all so restart the processing */ + if (nr_free) + goto restart; + + /* Not allowed to fall through or break because + * following context is inside spinlock while we are + * outside here. + */ + goto out; + + } + } + + /* remove range of pages from the pool */ + if (freed_pages) { + ttm_pool_update_free_locked(pool, freed_pages); + nr_free -= freed_pages; + } + + spin_unlock_irqrestore(&pool->lock, irq_flags); + + if (freed_pages) + ttm_dma_pages_put(pool, &d_pages, pages_to_free, freed_pages); +out: + kfree(pages_to_free); + return nr_free; +} + +static void ttm_dma_free_pool(struct device *dev, enum pool_type type) +{ + struct device_pools *p; + struct dma_pool *pool; + + if (!dev) + return; + + mutex_lock(&_manager->lock); + list_for_each_entry_reverse(p, &_manager->pools, pools) { + if (p->dev != dev) + continue; + pool = p->pool; + if (pool->type != type) + continue; + + list_del(&p->pools); + kfree(p); + _manager->npools--; + break; + } + list_for_each_entry_reverse(pool, &dev->dma_pools, pools) { + if (pool->type != type) + continue; + /* Takes a spinlock.. */ + ttm_dma_page_pool_free(pool, FREE_ALL_PAGES); + WARN_ON(((pool->npages_in_use + pool->npages_free) != 0)); + /* This code path is called after _all_ references to the + * struct device has been dropped - so nobody should be + * touching it. In case somebody is trying to _add_ we are + * guarded by the mutex. */ + list_del(&pool->pools); + kfree(pool); + break; + } + mutex_unlock(&_manager->lock); +} + +/* + * On free-ing of the 'struct device' this deconstructor is run. + * Albeit the pool might have already been freed earlier. + */ +static void ttm_dma_pool_release(struct device *dev, void *res) +{ + struct dma_pool *pool = *(struct dma_pool **)res; + + if (pool) + ttm_dma_free_pool(dev, pool->type); +} + +static int ttm_dma_pool_match(struct device *dev, void *res, void *match_data) +{ + return *(struct dma_pool **)res == match_data; +} + +static struct dma_pool *ttm_dma_pool_init(struct device *dev, gfp_t flags, + enum pool_type type) +{ + char *n[] = {"wc", "uc", "cached", " dma32", "unknown",}; + enum pool_type t[] = {IS_WC, IS_UC, IS_CACHED, IS_DMA32, IS_UNDEFINED}; + struct device_pools *sec_pool = NULL; + struct dma_pool *pool = NULL, **ptr; + unsigned i; + int ret = -ENODEV; + char *p; + + if (!dev) + return NULL; + + ptr = devres_alloc(ttm_dma_pool_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return NULL; + + ret = -ENOMEM; + + pool = kmalloc_node(sizeof(struct dma_pool), GFP_KERNEL, + dev_to_node(dev)); + if (!pool) + goto err_mem; + + sec_pool = kmalloc_node(sizeof(struct device_pools), GFP_KERNEL, + dev_to_node(dev)); + if (!sec_pool) + goto err_mem; + + INIT_LIST_HEAD(&sec_pool->pools); + sec_pool->dev = dev; + sec_pool->pool = pool; + + INIT_LIST_HEAD(&pool->free_list); + INIT_LIST_HEAD(&pool->inuse_list); + INIT_LIST_HEAD(&pool->pools); + spin_lock_init(&pool->lock); + pool->dev = dev; + pool->npages_free = pool->npages_in_use = 0; + pool->nfrees = 0; + pool->gfp_flags = flags; + pool->size = PAGE_SIZE; + pool->type = type; + pool->nrefills = 0; + p = pool->name; + for (i = 0; i < 5; i++) { + if (type & t[i]) { + p += snprintf(p, sizeof(pool->name) - (p - pool->name), + "%s", n[i]); + } + } + *p = 0; + /* We copy the name for pr_ calls b/c when dma_pool_destroy is called + * - the kobj->name has already been deallocated.*/ + snprintf(pool->dev_name, sizeof(pool->dev_name), "%s %s", + dev_driver_string(dev), dev_name(dev)); + mutex_lock(&_manager->lock); + /* You can get the dma_pool from either the global: */ + list_add(&sec_pool->pools, &_manager->pools); + _manager->npools++; + /* or from 'struct device': */ + list_add(&pool->pools, &dev->dma_pools); + mutex_unlock(&_manager->lock); + + *ptr = pool; + devres_add(dev, ptr); + + return pool; +err_mem: + devres_free(ptr); + kfree(sec_pool); + kfree(pool); + return ERR_PTR(ret); +} + +static struct dma_pool *ttm_dma_find_pool(struct device *dev, + enum pool_type type) +{ + struct dma_pool *pool, *tmp, *found = NULL; + + if (type == IS_UNDEFINED) + return found; + + /* NB: We iterate on the 'struct dev' which has no spinlock, but + * it does have a kref which we have taken. The kref is taken during + * graphic driver loading - in the drm_pci_init it calls either + * pci_dev_get or pci_register_driver which both end up taking a kref + * on 'struct device'. + * + * On teardown, the graphic drivers end up quiescing the TTM (put_pages) + * and calls the dev_res deconstructors: ttm_dma_pool_release. The nice + * thing is at that point of time there are no pages associated with the + * driver so this function will not be called. + */ + list_for_each_entry_safe(pool, tmp, &dev->dma_pools, pools) { + if (pool->type != type) + continue; + found = pool; + break; + } + return found; +} + +/* + * Free pages the pages that failed to change the caching state. If there + * are pages that have changed their caching state already put them to the + * pool. + */ +static void ttm_dma_handle_caching_state_failure(struct dma_pool *pool, + struct list_head *d_pages, + struct page **failed_pages, + unsigned cpages) +{ + struct dma_page *d_page, *tmp; + struct page *p; + unsigned i = 0; + + p = failed_pages[0]; + if (!p) + return; + /* Find the failed page. */ + list_for_each_entry_safe(d_page, tmp, d_pages, page_list) { + if (d_page->p != p) + continue; + /* .. and then progress over the full list. */ + list_del(&d_page->page_list); + __ttm_dma_free_page(pool, d_page); + if (++i < cpages) + p = failed_pages[i]; + else + break; + } + +} + +/* + * Allocate 'count' pages, and put 'need' number of them on the + * 'pages' and as well on the 'dma_address' starting at 'dma_offset' offset. + * The full list of pages should also be on 'd_pages'. + * We return zero for success, and negative numbers as errors. + */ +static int ttm_dma_pool_alloc_new_pages(struct dma_pool *pool, + struct list_head *d_pages, + unsigned count) +{ + struct page **caching_array; + struct dma_page *dma_p; + struct page *p; + int r = 0; + unsigned i, cpages; + unsigned max_cpages = min(count, + (unsigned)(PAGE_SIZE/sizeof(struct page *))); + + /* allocate array for page caching change */ + caching_array = kmalloc(max_cpages*sizeof(struct page *), GFP_KERNEL); + + if (!caching_array) { + pr_err("%s: Unable to allocate table for new pages\n", + pool->dev_name); + return -ENOMEM; + } + + if (count > 1) { + pr_debug("%s: (%s:%d) Getting %d pages\n", + pool->dev_name, pool->name, current->pid, count); + } + + for (i = 0, cpages = 0; i < count; ++i) { + dma_p = __ttm_dma_alloc_page(pool); + if (!dma_p) { + pr_err("%s: Unable to get page %u\n", + pool->dev_name, i); + + /* store already allocated pages in the pool after + * setting the caching state */ + if (cpages) { + r = ttm_set_pages_caching(pool, caching_array, + cpages); + if (r) + ttm_dma_handle_caching_state_failure( + pool, d_pages, caching_array, + cpages); + } + r = -ENOMEM; + goto out; + } + p = dma_p->p; +#ifdef CONFIG_HIGHMEM + /* gfp flags of highmem page should never be dma32 so we + * we should be fine in such case + */ + if (!PageHighMem(p)) +#endif + { + caching_array[cpages++] = p; + if (cpages == max_cpages) { + /* Note: Cannot hold the spinlock */ + r = ttm_set_pages_caching(pool, caching_array, + cpages); + if (r) { + ttm_dma_handle_caching_state_failure( + pool, d_pages, caching_array, + cpages); + goto out; + } + cpages = 0; + } + } + list_add(&dma_p->page_list, d_pages); + } + + if (cpages) { + r = ttm_set_pages_caching(pool, caching_array, cpages); + if (r) + ttm_dma_handle_caching_state_failure(pool, d_pages, + caching_array, cpages); + } +out: + kfree(caching_array); + return r; +} + +/* + * @return count of pages still required to fulfill the request. + */ +static int ttm_dma_page_pool_fill_locked(struct dma_pool *pool, + unsigned long *irq_flags) +{ + unsigned count = _manager->options.small; + int r = pool->npages_free; + + if (count > pool->npages_free) { + struct list_head d_pages; + + INIT_LIST_HEAD(&d_pages); + + spin_unlock_irqrestore(&pool->lock, *irq_flags); + + /* Returns how many more are neccessary to fulfill the + * request. */ + r = ttm_dma_pool_alloc_new_pages(pool, &d_pages, count); + + spin_lock_irqsave(&pool->lock, *irq_flags); + if (!r) { + /* Add the fresh to the end.. */ + list_splice(&d_pages, &pool->free_list); + ++pool->nrefills; + pool->npages_free += count; + r = count; + } else { + struct dma_page *d_page; + unsigned cpages = 0; + + pr_err("%s: Failed to fill %s pool (r:%d)!\n", + pool->dev_name, pool->name, r); + + list_for_each_entry(d_page, &d_pages, page_list) { + cpages++; + } + list_splice_tail(&d_pages, &pool->free_list); + pool->npages_free += cpages; + r = cpages; + } + } + return r; +} + +/* + * @return count of pages still required to fulfill the request. + * The populate list is actually a stack (not that is matters as TTM + * allocates one page at a time. + */ +static int ttm_dma_pool_get_pages(struct dma_pool *pool, + struct ttm_dma_tt *ttm_dma, + unsigned index) +{ + struct dma_page *d_page; + struct ttm_tt *ttm = &ttm_dma->ttm; + unsigned long irq_flags; + int count, r = -ENOMEM; + + spin_lock_irqsave(&pool->lock, irq_flags); + count = ttm_dma_page_pool_fill_locked(pool, &irq_flags); + if (count) { + d_page = list_first_entry(&pool->free_list, struct dma_page, page_list); + ttm->pages[index] = d_page->p; + ttm_dma->dma_address[index] = d_page->dma; + list_move_tail(&d_page->page_list, &ttm_dma->pages_list); + r = 0; + pool->npages_in_use += 1; + pool->npages_free -= 1; + } + spin_unlock_irqrestore(&pool->lock, irq_flags); + return r; +} + +/* + * On success pages list will hold count number of correctly + * cached pages. On failure will hold the negative return value (-ENOMEM, etc). + */ +int ttm_dma_populate(struct ttm_dma_tt *ttm_dma, struct device *dev) +{ + struct ttm_tt *ttm = &ttm_dma->ttm; + struct ttm_mem_global *mem_glob = ttm->glob->mem_glob; + struct dma_pool *pool; + enum pool_type type; + unsigned i; + gfp_t gfp_flags; + int ret; + + if (ttm->state != tt_unpopulated) + return 0; + + type = ttm_to_type(ttm->page_flags, ttm->caching_state); + if (ttm->page_flags & TTM_PAGE_FLAG_DMA32) + gfp_flags = GFP_USER | GFP_DMA32; + else + gfp_flags = GFP_HIGHUSER; + if (ttm->page_flags & TTM_PAGE_FLAG_ZERO_ALLOC) + gfp_flags |= __GFP_ZERO; + + pool = ttm_dma_find_pool(dev, type); + if (!pool) { + pool = ttm_dma_pool_init(dev, gfp_flags, type); + if (IS_ERR_OR_NULL(pool)) { + return -ENOMEM; + } + } + + INIT_LIST_HEAD(&ttm_dma->pages_list); + for (i = 0; i < ttm->num_pages; ++i) { + ret = ttm_dma_pool_get_pages(pool, ttm_dma, i); + if (ret != 0) { + ttm_dma_unpopulate(ttm_dma, dev); + return -ENOMEM; + } + + ret = ttm_mem_global_alloc_page(mem_glob, ttm->pages[i], + false, false); + if (unlikely(ret != 0)) { + ttm_dma_unpopulate(ttm_dma, dev); + return -ENOMEM; + } + } + + if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { + ret = ttm_tt_swapin(ttm); + if (unlikely(ret != 0)) { + ttm_dma_unpopulate(ttm_dma, dev); + return ret; + } + } + + ttm->state = tt_unbound; + return 0; +} +EXPORT_SYMBOL_GPL(ttm_dma_populate); + +/* Put all pages in pages list to correct pool to wait for reuse */ +void ttm_dma_unpopulate(struct ttm_dma_tt *ttm_dma, struct device *dev) +{ + struct ttm_tt *ttm = &ttm_dma->ttm; + struct dma_pool *pool; + struct dma_page *d_page, *next; + enum pool_type type; + bool is_cached = false; + unsigned count = 0, i, npages = 0; + unsigned long irq_flags; + + type = ttm_to_type(ttm->page_flags, ttm->caching_state); + pool = ttm_dma_find_pool(dev, type); + if (!pool) + return; + + is_cached = (ttm_dma_find_pool(pool->dev, + ttm_to_type(ttm->page_flags, tt_cached)) == pool); + + /* make sure pages array match list and count number of pages */ + list_for_each_entry(d_page, &ttm_dma->pages_list, page_list) { + ttm->pages[count] = d_page->p; + count++; + } + + spin_lock_irqsave(&pool->lock, irq_flags); + pool->npages_in_use -= count; + if (is_cached) { + pool->nfrees += count; + } else { + pool->npages_free += count; + list_splice(&ttm_dma->pages_list, &pool->free_list); + npages = count; + if (pool->npages_free > _manager->options.max_size) { + npages = pool->npages_free - _manager->options.max_size; + /* free at least NUM_PAGES_TO_ALLOC number of pages + * to reduce calls to set_memory_wb */ + if (npages < NUM_PAGES_TO_ALLOC) + npages = NUM_PAGES_TO_ALLOC; + } + } + spin_unlock_irqrestore(&pool->lock, irq_flags); + + if (is_cached) { + list_for_each_entry_safe(d_page, next, &ttm_dma->pages_list, page_list) { + ttm_mem_global_free_page(ttm->glob->mem_glob, + d_page->p); + ttm_dma_page_put(pool, d_page); + } + } else { + for (i = 0; i < count; i++) { + ttm_mem_global_free_page(ttm->glob->mem_glob, + ttm->pages[i]); + } + } + + INIT_LIST_HEAD(&ttm_dma->pages_list); + for (i = 0; i < ttm->num_pages; i++) { + ttm->pages[i] = NULL; + ttm_dma->dma_address[i] = 0; + } + + /* shrink pool if necessary (only on !is_cached pools)*/ + if (npages) + ttm_dma_page_pool_free(pool, npages); + ttm->state = tt_unpopulated; +} +EXPORT_SYMBOL_GPL(ttm_dma_unpopulate); + +/** + * Callback for mm to request pool to reduce number of page held. + * + * XXX: (dchinner) Deadlock warning! + * + * ttm_dma_page_pool_free() does GFP_KERNEL memory allocation, and so attention + * needs to be paid to sc->gfp_mask to determine if this can be done or not. + * GFP_KERNEL memory allocation in a GFP_ATOMIC reclaim context woul dbe really + * bad. + * + * I'm getting sadder as I hear more pathetical whimpers about needing per-pool + * shrinkers + */ +static unsigned long +ttm_dma_pool_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) +{ + static atomic_t start_pool = ATOMIC_INIT(0); + unsigned idx = 0; + unsigned pool_offset = atomic_add_return(1, &start_pool); + unsigned shrink_pages = sc->nr_to_scan; + struct device_pools *p; + unsigned long freed = 0; + + if (list_empty(&_manager->pools)) + return SHRINK_STOP; + + mutex_lock(&_manager->lock); + pool_offset = pool_offset % _manager->npools; + list_for_each_entry(p, &_manager->pools, pools) { + unsigned nr_free; + + if (!p->dev) + continue; + if (shrink_pages == 0) + break; + /* Do it in round-robin fashion. */ + if (++idx < pool_offset) + continue; + nr_free = shrink_pages; + shrink_pages = ttm_dma_page_pool_free(p->pool, nr_free); + freed += nr_free - shrink_pages; + + pr_debug("%s: (%s:%d) Asked to shrink %d, have %d more to go\n", + p->pool->dev_name, p->pool->name, current->pid, + nr_free, shrink_pages); + } + mutex_unlock(&_manager->lock); + return freed; +} + +static unsigned long +ttm_dma_pool_shrink_count(struct shrinker *shrink, struct shrink_control *sc) +{ + struct device_pools *p; + unsigned long count = 0; + + mutex_lock(&_manager->lock); + list_for_each_entry(p, &_manager->pools, pools) + count += p->pool->npages_free; + mutex_unlock(&_manager->lock); + return count; +} + +static void ttm_dma_pool_mm_shrink_init(struct ttm_pool_manager *manager) +{ + manager->mm_shrink.count_objects = ttm_dma_pool_shrink_count; + manager->mm_shrink.scan_objects = &ttm_dma_pool_shrink_scan; + manager->mm_shrink.seeks = 1; + register_shrinker(&manager->mm_shrink); +} + +static void ttm_dma_pool_mm_shrink_fini(struct ttm_pool_manager *manager) +{ + unregister_shrinker(&manager->mm_shrink); +} + +int ttm_dma_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages) +{ + int ret = -ENOMEM; + + WARN_ON(_manager); + + pr_info("Initializing DMA pool allocator\n"); + + _manager = kzalloc(sizeof(*_manager), GFP_KERNEL); + if (!_manager) + goto err; + + mutex_init(&_manager->lock); + INIT_LIST_HEAD(&_manager->pools); + + _manager->options.max_size = max_pages; + _manager->options.small = SMALL_ALLOCATION; + _manager->options.alloc_size = NUM_PAGES_TO_ALLOC; + + /* This takes care of auto-freeing the _manager */ + ret = kobject_init_and_add(&_manager->kobj, &ttm_pool_kobj_type, + &glob->kobj, "dma_pool"); + if (unlikely(ret != 0)) { + kobject_put(&_manager->kobj); + goto err; + } + ttm_dma_pool_mm_shrink_init(_manager); + return 0; +err: + return ret; +} + +void ttm_dma_page_alloc_fini(void) +{ + struct device_pools *p, *t; + + pr_info("Finalizing DMA pool allocator\n"); + ttm_dma_pool_mm_shrink_fini(_manager); + + list_for_each_entry_safe_reverse(p, t, &_manager->pools, pools) { + dev_dbg(p->dev, "(%s:%d) Freeing.\n", p->pool->name, + current->pid); + WARN_ON(devres_destroy(p->dev, ttm_dma_pool_release, + ttm_dma_pool_match, p->pool)); + ttm_dma_free_pool(p->dev, p->pool->type); + } + kobject_put(&_manager->kobj); + _manager = NULL; +} + +int ttm_dma_page_alloc_debugfs(struct seq_file *m, void *data) +{ + struct device_pools *p; + struct dma_pool *pool = NULL; + char *h[] = {"pool", "refills", "pages freed", "inuse", "available", + "name", "virt", "busaddr"}; + + if (!_manager) { + seq_printf(m, "No pool allocator running.\n"); + return 0; + } + seq_printf(m, "%13s %12s %13s %8s %8s %8s\n", + h[0], h[1], h[2], h[3], h[4], h[5]); + mutex_lock(&_manager->lock); + list_for_each_entry(p, &_manager->pools, pools) { + struct device *dev = p->dev; + if (!dev) + continue; + pool = p->pool; + seq_printf(m, "%13s %12ld %13ld %8d %8d %8s\n", + pool->name, pool->nrefills, + pool->nfrees, pool->npages_in_use, + pool->npages_free, + pool->dev_name); + } + mutex_unlock(&_manager->lock); + return 0; +} +EXPORT_SYMBOL_GPL(ttm_dma_page_alloc_debugfs); + +#endif |