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authorMark Brown <broonie@linaro.org>2013-12-09 11:37:00 +0000
committerMark Brown <broonie@linaro.org>2013-12-09 11:37:00 +0000
commiteed4bafd63b5584adb832a582a931ecba41dec55 (patch)
tree5855807caaf53aec80037b2635eb2e2c0744565b /drivers/staging/android/ion/ion_page_pool.c
parent8bb495e3f02401ee6f76d1b1d77f3ac9f079e376 (diff)
parent2c06cb20454795a38876be5bd93dd6a8ddcc9d98 (diff)
Merge branch 'android-3.10' of https://android.googlesource.com/kernel/common into lsk-v3.10-aosp
Diffstat (limited to 'drivers/staging/android/ion/ion_page_pool.c')
-rw-r--r--drivers/staging/android/ion/ion_page_pool.c195
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/staging/android/ion/ion_page_pool.c b/drivers/staging/android/ion/ion_page_pool.c
new file mode 100644
index 00000000000..b052ff6bf38
--- /dev/null
+++ b/drivers/staging/android/ion/ion_page_pool.c
@@ -0,0 +1,195 @@
+/*
+ * drivers/gpu/ion/ion_mem_pool.c
+ *
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/debugfs.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/fs.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include "ion_priv.h"
+
+struct ion_page_pool_item {
+ struct page *page;
+ struct list_head list;
+};
+
+static void *ion_page_pool_alloc_pages(struct ion_page_pool *pool)
+{
+ struct page *page = alloc_pages(pool->gfp_mask, pool->order);
+
+ if (!page)
+ return NULL;
+ ion_pages_sync_for_device(NULL, page, PAGE_SIZE << pool->order,
+ DMA_BIDIRECTIONAL);
+ return page;
+}
+
+static void ion_page_pool_free_pages(struct ion_page_pool *pool,
+ struct page *page)
+{
+ __free_pages(page, pool->order);
+}
+
+static int ion_page_pool_add(struct ion_page_pool *pool, struct page *page)
+{
+ struct ion_page_pool_item *item;
+
+ item = kmalloc(sizeof(struct ion_page_pool_item), GFP_KERNEL);
+ if (!item)
+ return -ENOMEM;
+
+ mutex_lock(&pool->mutex);
+ item->page = page;
+ if (PageHighMem(page)) {
+ list_add_tail(&item->list, &pool->high_items);
+ pool->high_count++;
+ } else {
+ list_add_tail(&item->list, &pool->low_items);
+ pool->low_count++;
+ }
+ mutex_unlock(&pool->mutex);
+ return 0;
+}
+
+static struct page *ion_page_pool_remove(struct ion_page_pool *pool, bool high)
+{
+ struct ion_page_pool_item *item;
+ struct page *page;
+
+ if (high) {
+ BUG_ON(!pool->high_count);
+ item = list_first_entry(&pool->high_items,
+ struct ion_page_pool_item, list);
+ pool->high_count--;
+ } else {
+ BUG_ON(!pool->low_count);
+ item = list_first_entry(&pool->low_items,
+ struct ion_page_pool_item, list);
+ pool->low_count--;
+ }
+
+ list_del(&item->list);
+ page = item->page;
+ kfree(item);
+ return page;
+}
+
+void *ion_page_pool_alloc(struct ion_page_pool *pool)
+{
+ struct page *page = NULL;
+
+ BUG_ON(!pool);
+
+ mutex_lock(&pool->mutex);
+ if (pool->high_count)
+ page = ion_page_pool_remove(pool, true);
+ else if (pool->low_count)
+ page = ion_page_pool_remove(pool, false);
+ mutex_unlock(&pool->mutex);
+
+ if (!page)
+ page = ion_page_pool_alloc_pages(pool);
+
+ return page;
+}
+
+void ion_page_pool_free(struct ion_page_pool *pool, struct page* page)
+{
+ int ret;
+
+ ret = ion_page_pool_add(pool, page);
+ if (ret)
+ ion_page_pool_free_pages(pool, page);
+}
+
+static int ion_page_pool_total(struct ion_page_pool *pool, bool high)
+{
+ int total = 0;
+
+ total += high ? (pool->high_count + pool->low_count) *
+ (1 << pool->order) :
+ pool->low_count * (1 << pool->order);
+ return total;
+}
+
+int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask,
+ int nr_to_scan)
+{
+ int nr_freed = 0;
+ int i;
+ bool high;
+
+ high = gfp_mask & __GFP_HIGHMEM;
+
+ if (nr_to_scan == 0)
+ return ion_page_pool_total(pool, high);
+
+ for (i = 0; i < nr_to_scan; i++) {
+ struct page *page;
+
+ mutex_lock(&pool->mutex);
+ if (high && pool->high_count) {
+ page = ion_page_pool_remove(pool, true);
+ } else if (pool->low_count) {
+ page = ion_page_pool_remove(pool, false);
+ } else {
+ mutex_unlock(&pool->mutex);
+ break;
+ }
+ mutex_unlock(&pool->mutex);
+ ion_page_pool_free_pages(pool, page);
+ nr_freed += (1 << pool->order);
+ }
+
+ return nr_freed;
+}
+
+struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order)
+{
+ struct ion_page_pool *pool = kmalloc(sizeof(struct ion_page_pool),
+ GFP_KERNEL);
+ if (!pool)
+ return NULL;
+ pool->high_count = 0;
+ pool->low_count = 0;
+ INIT_LIST_HEAD(&pool->low_items);
+ INIT_LIST_HEAD(&pool->high_items);
+ pool->gfp_mask = gfp_mask;
+ pool->order = order;
+ mutex_init(&pool->mutex);
+ plist_node_init(&pool->list, order);
+
+ return pool;
+}
+
+void ion_page_pool_destroy(struct ion_page_pool *pool)
+{
+ kfree(pool);
+}
+
+static int __init ion_page_pool_init(void)
+{
+ return 0;
+}
+
+static void __exit ion_page_pool_exit(void)
+{
+}
+
+module_init(ion_page_pool_init);
+module_exit(ion_page_pool_exit);