--- /dev/null
+/*
+ * Copyright (c) Red Hat Inc.
+
+ * 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.
+ *
+ * Authors: Dave Airlie <airlied@redhat.com>
+ * Jerome Glisse <jglisse@redhat.com>
+ * Pauli Nieminen <suokkos@gmail.com>
+ */
+
+/* simple list based uncached page pool
+ * - Pool collects resently freed pages for reuse
+ * - Use page->lru to keep a free list
+ * - doesn't track currently in use pages
+ */
+
+#define pr_fmt(fmt) "[TTM] " fmt
+
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/highmem.h>
+#include <linux/mm_types.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/seq_file.h> /* for seq_printf */
+#include <linux/slab.h>
+#include <linux/dma-mapping.h>
+
+#include <linux/atomic.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 16
+#define FREE_ALL_PAGES (~0U)
+/* times are in msecs */
+#define PAGE_FREE_INTERVAL 1000
+
+/**
+ * struct ttm_page_pool - Pool to reuse recently allocated uc/wc pages.
+ *
+ * @lock: Protects the shared pool from concurrnet access. Must be used with
+ * irqsave/irqrestore variants because pool allocator maybe called from
+ * delayed work.
+ * @fill_lock: Prevent concurrent calls to fill.
+ * @list: Pool of free uc/wc pages for fast reuse.
+ * @gfp_flags: Flags to pass for alloc_page.
+ * @npages: Number of pages in pool.
+ */
+struct ttm_page_pool {
+ spinlock_t lock;
+ bool fill_lock;
+ struct list_head list;
+ gfp_t gfp_flags;
+ unsigned npages;
+ char *name;
+ unsigned long nfrees;
+ unsigned long nrefills;
+};
+
+/**
+ * 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;
+};
+
+#define NUM_POOLS 4
+
+/**
+ * struct ttm_pool_manager - Holds memory pools for fst allocation
+ *
+ * Manager is read only object for pool code so it doesn't need locking.
+ *
+ * @free_interval: minimum number of jiffies between freeing pages from pool.
+ * @page_alloc_inited: reference counting for pool allocation.
+ * @work: Work that is used to shrink the pool. Work is only run when there is
+ * some pages to free.
+ * @small_allocation: Limit in number of pages what is small allocation.
+ *
+ * @pools: All pool objects in use.
+ **/
+struct ttm_pool_manager {
+ struct kobject kobj;
+ struct shrinker mm_shrink;
+ struct ttm_pool_opts options;
+
+ union {
+ struct ttm_page_pool pools[NUM_POOLS];
+ struct {
+ struct ttm_page_pool wc_pool;
+ struct ttm_page_pool uc_pool;
+ struct ttm_page_pool wc_pool_dma32;
+ struct ttm_page_pool uc_pool_dma32;
+ } ;
+ };
+};
+
+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,
+};
+
+static struct ttm_pool_manager *_manager;
+
+#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
+
+/**
+ * Select the right pool or requested caching state and ttm flags. */
+static struct ttm_page_pool *ttm_get_pool(int flags,
+ enum ttm_caching_state cstate)
+{
+ int pool_index;
+
+ if (cstate == tt_cached)
+ return NULL;
+
+ if (cstate == tt_wc)
+ pool_index = 0x0;
+ else
+ pool_index = 0x1;
+
+ if (flags & TTM_PAGE_FLAG_DMA32)
+ pool_index |= 0x2;
+
+ return &_manager->pools[pool_index];
+}
+
+/* set memory back to wb and free the pages. */
+static void ttm_pages_put(struct page *pages[], unsigned npages)
+{
+ unsigned i;
+ if (set_pages_array_wb(pages, npages))
+ pr_err("Failed to set %d pages to wb!\n", npages);
+ for (i = 0; i < npages; ++i)
+ __free_page(pages[i]);
+}
+
+static void ttm_pool_update_free_locked(struct ttm_page_pool *pool,
+ unsigned freed_pages)
+{
+ pool->npages -= freed_pages;
+ pool->nfrees += freed_pages;
+}
+
+/**
+ * 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
+ * @free_all: If set to true will free all pages in pool
+ * @use_static: Safe to use static buffer
+ **/
+static int ttm_page_pool_free(struct ttm_page_pool *pool, unsigned nr_free,
+ bool use_static)
+{
+ static struct page *static_buf[NUM_PAGES_TO_ALLOC];
+ unsigned long irq_flags;
+ struct page *p;
+ struct page **pages_to_free;
+ unsigned freed_pages = 0,
+ npages_to_free = nr_free;
+
+ if (NUM_PAGES_TO_ALLOC < nr_free)
+ npages_to_free = NUM_PAGES_TO_ALLOC;
+
+ if (use_static)
+ pages_to_free = static_buf;
+ else
+ pages_to_free = kmalloc(npages_to_free * sizeof(struct page *),
+ GFP_KERNEL);
+ if (!pages_to_free) {
+ pr_err("Failed to allocate memory for pool free operation\n");
+ return 0;
+ }
+
+restart:
+ spin_lock_irqsave(&pool->lock, irq_flags);
+
+ list_for_each_entry_reverse(p, &pool->list, lru) {
+ if (freed_pages >= npages_to_free)
+ break;
+
+ pages_to_free[freed_pages++] = p;
+ /* We can only remove NUM_PAGES_TO_ALLOC at a time. */
+ if (freed_pages >= NUM_PAGES_TO_ALLOC) {
+ /* remove range of pages from the pool */
+ __list_del(p->lru.prev, &pool->list);
+
+ 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_pages_put(pages_to_free, freed_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) {
+ __list_del(&p->lru, &pool->list);
+
+ ttm_pool_update_free_locked(pool, freed_pages);
+ nr_free -= freed_pages;
+ }
+
+ spin_unlock_irqrestore(&pool->lock, irq_flags);
+
+ if (freed_pages)
+ ttm_pages_put(pages_to_free, freed_pages);
+out:
+ if (pages_to_free != static_buf)
+ kfree(pages_to_free);
+ return nr_free;
+}
+
+/**
+ * Callback for mm to request pool to reduce number of page held.
+ *
+ * XXX: (dchinner) Deadlock warning!
+ *
+ * This code is crying out for a shrinker per pool....
+ */
+static unsigned long
+ttm_pool_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
+{
+ static DEFINE_MUTEX(lock);
+ static unsigned start_pool;
+ unsigned i;
+ unsigned pool_offset;
+ struct ttm_page_pool *pool;
+ int shrink_pages = sc->nr_to_scan;
+ unsigned long freed = 0;
+
+ if (!mutex_trylock(&lock))
+ return SHRINK_STOP;
+ pool_offset = ++start_pool % NUM_POOLS;
+ /* select start pool in round robin fashion */
+ for (i = 0; i < NUM_POOLS; ++i) {
+ unsigned nr_free = shrink_pages;
+ if (shrink_pages == 0)
+ break;
+ pool = &_manager->pools[(i + pool_offset)%NUM_POOLS];
+ /* OK to use static buffer since global mutex is held. */
+ shrink_pages = ttm_page_pool_free(pool, nr_free, true);
+ freed += nr_free - shrink_pages;
+ }
+ mutex_unlock(&lock);
+ return freed;
+}
+
+
+static unsigned long
+ttm_pool_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
+{
+ unsigned i;
+ unsigned long count = 0;
+
+ for (i = 0; i < NUM_POOLS; ++i)
+ count += _manager->pools[i].npages;
+
+ return count;
+}
+
+static void ttm_pool_mm_shrink_init(struct ttm_pool_manager *manager)
+{
+ manager->mm_shrink.count_objects = ttm_pool_shrink_count;
+ manager->mm_shrink.scan_objects = ttm_pool_shrink_scan;
+ manager->mm_shrink.seeks = 1;
+ register_shrinker(&manager->mm_shrink);
+}
+
+static void ttm_pool_mm_shrink_fini(struct ttm_pool_manager *manager)
+{
+ unregister_shrinker(&manager->mm_shrink);
+}
+
+static int ttm_set_pages_caching(struct page **pages,
+ enum ttm_caching_state cstate, unsigned cpages)
+{
+ int r = 0;
+ /* Set page caching */
+ switch (cstate) {
+ case tt_uncached:
+ r = set_pages_array_uc(pages, cpages);
+ if (r)
+ pr_err("Failed to set %d pages to uc!\n", cpages);
+ break;
+ case tt_wc:
+ r = set_pages_array_wc(pages, cpages);
+ if (r)
+ pr_err("Failed to set %d pages to wc!\n", cpages);
+ break;
+ default:
+ break;
+ }
+ return r;
+}
+
+/**
+ * Free pages the pages that failed to change the caching state. If there is
+ * any pages that have changed their caching state already put them to the
+ * pool.
+ */
+static void ttm_handle_caching_state_failure(struct list_head *pages,
+ int ttm_flags, enum ttm_caching_state cstate,
+ struct page **failed_pages, unsigned cpages)
+{
+ unsigned i;
+ /* Failed pages have to be freed */
+ for (i = 0; i < cpages; ++i) {
+ list_del(&failed_pages[i]->lru);
+ __free_page(failed_pages[i]);
+ }
+}
+
+/**
+ * Allocate new pages with correct caching.
+ *
+ * This function is reentrant if caller updates count depending on number of
+ * pages returned in pages array.
+ */
+static int ttm_alloc_new_pages(struct list_head *pages, gfp_t gfp_flags,
+ int ttm_flags, enum ttm_caching_state cstate, unsigned count)
+{
+ struct page **caching_array;
+ 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("Unable to allocate table for new pages\n");
+ return -ENOMEM;
+ }
+
+ for (i = 0, cpages = 0; i < count; ++i) {
+ p = alloc_page(gfp_flags);
+
+ if (!p) {
+ pr_err("Unable to get page %u\n", i);
+
+ /* store already allocated pages in the pool after
+ * setting the caching state */
+ if (cpages) {
+ r = ttm_set_pages_caching(caching_array,
+ cstate, cpages);
+ if (r)
+ ttm_handle_caching_state_failure(pages,
+ ttm_flags, cstate,
+ caching_array, cpages);
+ }
+ r = -ENOMEM;
+ goto out;
+ }
+
+#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) {
+
+ r = ttm_set_pages_caching(caching_array,
+ cstate, cpages);
+ if (r) {
+ ttm_handle_caching_state_failure(pages,
+ ttm_flags, cstate,
+ caching_array, cpages);
+ goto out;
+ }
+ cpages = 0;
+ }
+ }
+
+ list_add(&p->lru, pages);
+ }
+
+ if (cpages) {
+ r = ttm_set_pages_caching(caching_array, cstate, cpages);
+ if (r)
+ ttm_handle_caching_state_failure(pages,
+ ttm_flags, cstate,
+ caching_array, cpages);
+ }
+out:
+ kfree(caching_array);
+
+ return r;
+}
+
+/**
+ * Fill the given pool if there aren't enough pages and the requested number of
+ * pages is small.
+ */
+static void ttm_page_pool_fill_locked(struct ttm_page_pool *pool,
+ int ttm_flags, enum ttm_caching_state cstate, unsigned count,
+ unsigned long *irq_flags)
+{
+ struct page *p;
+ int r;
+ unsigned cpages = 0;
+ /**
+ * Only allow one pool fill operation at a time.
+ * If pool doesn't have enough pages for the allocation new pages are
+ * allocated from outside of pool.
+ */
+ if (pool->fill_lock)
+ return;
+
+ pool->fill_lock = true;
+
+ /* If allocation request is small and there are not enough
+ * pages in a pool we fill the pool up first. */
+ if (count < _manager->options.small
+ && count > pool->npages) {
+ struct list_head new_pages;
+ unsigned alloc_size = _manager->options.alloc_size;
+
+ /**
+ * Can't change page caching if in irqsave context. We have to
+ * drop the pool->lock.
+ */
+ spin_unlock_irqrestore(&pool->lock, *irq_flags);
+
+ INIT_LIST_HEAD(&new_pages);
+ r = ttm_alloc_new_pages(&new_pages, pool->gfp_flags, ttm_flags,
+ cstate, alloc_size);
+ spin_lock_irqsave(&pool->lock, *irq_flags);
+
+ if (!r) {
+ list_splice(&new_pages, &pool->list);
+ ++pool->nrefills;
+ pool->npages += alloc_size;
+ } else {
+ pr_err("Failed to fill pool (%p)\n", pool);
+ /* If we have any pages left put them to the pool. */
+ list_for_each_entry(p, &pool->list, lru) {
+ ++cpages;
+ }
+ list_splice(&new_pages, &pool->list);
+ pool->npages += cpages;
+ }
+
+ }
+ pool->fill_lock = false;
+}
+
+/**
+ * Cut 'count' number of pages from the pool and put them on the return list.
+ *
+ * @return count of pages still required to fulfill the request.
+ */
+static unsigned ttm_page_pool_get_pages(struct ttm_page_pool *pool,
+ struct list_head *pages,
+ int ttm_flags,
+ enum ttm_caching_state cstate,
+ unsigned count)
+{
+ unsigned long irq_flags;
+ struct list_head *p;
+ unsigned i;
+
+ spin_lock_irqsave(&pool->lock, irq_flags);
+ ttm_page_pool_fill_locked(pool, ttm_flags, cstate, count, &irq_flags);
+
+ if (count >= pool->npages) {
+ /* take all pages from the pool */
+ list_splice_init(&pool->list, pages);
+ count -= pool->npages;
+ pool->npages = 0;
+ goto out;
+ }
+ /* find the last pages to include for requested number of pages. Split
+ * pool to begin and halve it to reduce search space. */
+ if (count <= pool->npages/2) {
+ i = 0;
+ list_for_each(p, &pool->list) {
+ if (++i == count)
+ break;
+ }
+ } else {
+ i = pool->npages + 1;
+ list_for_each_prev(p, &pool->list) {
+ if (--i == count)
+ break;
+ }
+ }
+ /* Cut 'count' number of pages from the pool */
+ list_cut_position(pages, &pool->list, p);
+ pool->npages -= count;
+ count = 0;
+out:
+ spin_unlock_irqrestore(&pool->lock, irq_flags);
+ return count;
+}
+
+/* Put all pages in pages list to correct pool to wait for reuse */
+static void ttm_put_pages(struct page **pages, unsigned npages, int flags,
+ enum ttm_caching_state cstate)
+{
+ unsigned long irq_flags;
+ struct ttm_page_pool *pool = ttm_get_pool(flags, cstate);
+ unsigned i;
+
+ if (pool == NULL) {
+ /* No pool for this memory type so free the pages */
+ for (i = 0; i < npages; i++) {
+ if (pages[i]) {
+ if (page_count(pages[i]) != 1)
+ pr_err("Erroneous page count. Leaking pages.\n");
+ __free_page(pages[i]);
+ pages[i] = NULL;
+ }
+ }
+ return;
+ }
+
+ spin_lock_irqsave(&pool->lock, irq_flags);
+ for (i = 0; i < npages; i++) {
+ if (pages[i]) {
+ if (page_count(pages[i]) != 1)
+ pr_err("Erroneous page count. Leaking pages.\n");
+ list_add_tail(&pages[i]->lru, &pool->list);
+ pages[i] = NULL;
+ pool->npages++;
+ }
+ }
+ /* Check that we don't go over the pool limit */
+ npages = 0;
+ if (pool->npages > _manager->options.max_size) {
+ npages = pool->npages - _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 (npages)
+ ttm_page_pool_free(pool, npages, false);
+}
+
+/*
+ * On success pages list will hold count number of correctly
+ * cached pages.
+ */
+static int ttm_get_pages(struct page **pages, unsigned npages, int flags,
+ enum ttm_caching_state cstate)
+{
+ struct ttm_page_pool *pool = ttm_get_pool(flags, cstate);
+ struct list_head plist;
+ struct page *p = NULL;
+ gfp_t gfp_flags = GFP_USER;
+ unsigned count;
+ int r;
+
+ /* set zero flag for page allocation if required */
+ if (flags & TTM_PAGE_FLAG_ZERO_ALLOC)
+ gfp_flags |= __GFP_ZERO;
+
+ /* No pool for cached pages */
+ if (pool == NULL) {
+ if (flags & TTM_PAGE_FLAG_DMA32)
+ gfp_flags |= GFP_DMA32;
+ else
+ gfp_flags |= GFP_HIGHUSER;
+
+ for (r = 0; r < npages; ++r) {
+ p = alloc_page(gfp_flags);
+ if (!p) {
+
+ pr_err("Unable to allocate page\n");
+ return -ENOMEM;
+ }
+
+ pages[r] = p;
+ }
+ return 0;
+ }
+
+ /* combine zero flag to pool flags */
+ gfp_flags |= pool->gfp_flags;
+
+ /* First we take pages from the pool */
+ INIT_LIST_HEAD(&plist);
+ npages = ttm_page_pool_get_pages(pool, &plist, flags, cstate, npages);
+ count = 0;
+ list_for_each_entry(p, &plist, lru) {
+ pages[count++] = p;
+ }
+
+ /* clear the pages coming from the pool if requested */
+ if (flags & TTM_PAGE_FLAG_ZERO_ALLOC) {
+ list_for_each_entry(p, &plist, lru) {
+ if (PageHighMem(p))
+ clear_highpage(p);
+ else
+ clear_page(page_address(p));
+ }
+ }
+
+ /* If pool didn't have enough pages allocate new one. */
+ if (npages > 0) {
+ /* ttm_alloc_new_pages doesn't reference pool so we can run
+ * multiple requests in parallel.
+ **/
+ INIT_LIST_HEAD(&plist);
+ r = ttm_alloc_new_pages(&plist, gfp_flags, flags, cstate, npages);
+ list_for_each_entry(p, &plist, lru) {
+ pages[count++] = p;
+ }
+ if (r) {
+ /* If there is any pages in the list put them back to
+ * the pool. */
+ pr_err("Failed to allocate extra pages for large request\n");
+ ttm_put_pages(pages, count, flags, cstate);
+ return r;
+ }
+ }
+
+ return 0;
+}
+
+static void ttm_page_pool_init_locked(struct ttm_page_pool *pool, gfp_t flags,
+ char *name)
+{
+ spin_lock_init(&pool->lock);
+ pool->fill_lock = false;
+ INIT_LIST_HEAD(&pool->list);
+ pool->npages = pool->nfrees = 0;
+ pool->gfp_flags = flags;
+ pool->name = name;
+}
+
+int ttm_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages)
+{
+ int ret;
+
+ WARN_ON(_manager);
+
+ pr_info("Initializing pool allocator\n");
+
+ _manager = kzalloc(sizeof(*_manager), GFP_KERNEL);
+
+ ttm_page_pool_init_locked(&_manager->wc_pool, GFP_HIGHUSER, "wc");
+
+ ttm_page_pool_init_locked(&_manager->uc_pool, GFP_HIGHUSER, "uc");
+
+ ttm_page_pool_init_locked(&_manager->wc_pool_dma32,
+ GFP_USER | GFP_DMA32, "wc dma");
+
+ ttm_page_pool_init_locked(&_manager->uc_pool_dma32,
+ GFP_USER | GFP_DMA32, "uc dma");
+
+ _manager->options.max_size = max_pages;
+ _manager->options.small = SMALL_ALLOCATION;
+ _manager->options.alloc_size = NUM_PAGES_TO_ALLOC;
+
+ ret = kobject_init_and_add(&_manager->kobj, &ttm_pool_kobj_type,
+ &glob->kobj, "pool");
+ if (unlikely(ret != 0)) {
+ kobject_put(&_manager->kobj);
+ _manager = NULL;
+ return ret;
+ }
+
+ ttm_pool_mm_shrink_init(_manager);
+
+ return 0;
+}
+
+void ttm_page_alloc_fini(void)
+{
+ int i;
+
+ pr_info("Finalizing pool allocator\n");
+ ttm_pool_mm_shrink_fini(_manager);
+
+ /* OK to use static buffer since global mutex is no longer used. */
+ for (i = 0; i < NUM_POOLS; ++i)
+ ttm_page_pool_free(&_manager->pools[i], FREE_ALL_PAGES, true);
+
+ kobject_put(&_manager->kobj);
+ _manager = NULL;
+}
+
+int ttm_pool_populate(struct ttm_tt *ttm)
+{
+ struct ttm_mem_global *mem_glob = ttm->glob->mem_glob;
+ unsigned i;
+ int ret;
+
+ if (ttm->state != tt_unpopulated)
+ return 0;
+
+ for (i = 0; i < ttm->num_pages; ++i) {
+ ret = ttm_get_pages(&ttm->pages[i], 1,
+ ttm->page_flags,
+ ttm->caching_state);
+ if (ret != 0) {
+ ttm_pool_unpopulate(ttm);
+ return -ENOMEM;
+ }
+
+ ret = ttm_mem_global_alloc_page(mem_glob, ttm->pages[i],
+ false, false);
+ if (unlikely(ret != 0)) {
+ ttm_pool_unpopulate(ttm);
+ return -ENOMEM;
+ }
+ }
+
+ if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
+ ret = ttm_tt_swapin(ttm);
+ if (unlikely(ret != 0)) {
+ ttm_pool_unpopulate(ttm);
+ return ret;
+ }
+ }
+
+ ttm->state = tt_unbound;
+ return 0;
+}
+EXPORT_SYMBOL(ttm_pool_populate);
+
+void ttm_pool_unpopulate(struct ttm_tt *ttm)
+{
+ unsigned i;
+
+ for (i = 0; i < ttm->num_pages; ++i) {
+ if (ttm->pages[i]) {
+ ttm_mem_global_free_page(ttm->glob->mem_glob,
+ ttm->pages[i]);
+ ttm_put_pages(&ttm->pages[i], 1,
+ ttm->page_flags,
+ ttm->caching_state);
+ }
+ }
+ ttm->state = tt_unpopulated;
+}
+EXPORT_SYMBOL(ttm_pool_unpopulate);
+
+int ttm_page_alloc_debugfs(struct seq_file *m, void *data)
+{
+ struct ttm_page_pool *p;
+ unsigned i;
+ char *h[] = {"pool", "refills", "pages freed", "size"};
+ if (!_manager) {
+ seq_printf(m, "No pool allocator running.\n");
+ return 0;
+ }
+ seq_printf(m, "%6s %12s %13s %8s\n",
+ h[0], h[1], h[2], h[3]);
+ for (i = 0; i < NUM_POOLS; ++i) {
+ p = &_manager->pools[i];
+
+ seq_printf(m, "%6s %12ld %13ld %8d\n",
+ p->name, p->nrefills,
+ p->nfrees, p->npages);
+ }
+ return 0;
+}
+EXPORT_SYMBOL(ttm_page_alloc_debugfs);
Code Review / kvmfornfv.git / blobdiff