ion_page_pool: Remove prealloc tracking

A separate heap will be used for the preallocation feature.
Also remove an associated ion_buffer private flag.

Change-Id: I8df74307d4c3461198de0a58f6b8ec7c8bef1f12
Signed-off-by: Patrick Daly <pdaly@codeaurora.org>

drivers/staging/android/ion/ion_page_pool.c

@@ -54,8 +54,7 @@ static void ion_page_pool_free_pages(struct ion_page_pool *pool,
 	__free_pages(page, pool->order);
 }
 
-static int ion_page_pool_add(struct ion_page_pool *pool, struct page *page,
+static int ion_page_pool_add(struct ion_page_pool *pool, struct page *page)
-			     bool prefetch)
 {
 	mutex_lock(&pool->mutex);
 	if (PageHighMem(page)) {
@@ -65,15 +64,11 @@ static int ion_page_pool_add(struct ion_page_pool *pool, struct page *page,
 		list_add_tail(&page->lru, &pool->low_items);
 		pool->low_count++;
 	}
-	if (!prefetch)
-		pool->nr_unreserved++;
-
 	mutex_unlock(&pool->mutex);
 	return 0;
 }
 
-static struct page *ion_page_pool_remove(struct ion_page_pool *pool, bool high,
+static struct page *ion_page_pool_remove(struct ion_page_pool *pool, bool high)
-					 bool prefetch)
 {
 	struct page *page;
 
@@ -87,13 +82,6 @@ static struct page *ion_page_pool_remove(struct ion_page_pool *pool, bool high,
 		pool->low_count--;
 	}
 
-	if (prefetch) {
-		BUG_ON(!pool->nr_unreserved);
-		pool->nr_unreserved--;
-	}
-	pool->nr_unreserved = min_t(int, pool->high_count + pool->low_count,
-						pool->nr_unreserved);
-
 	list_del(&page->lru);
 	return page;
 }
@@ -108,9 +96,9 @@ void *ion_page_pool_alloc(struct ion_page_pool *pool, bool *from_pool)
 
 	if (mutex_trylock(&pool->mutex)) {
 		if (pool->high_count)
-			page = ion_page_pool_remove(pool, true, false);
+			page = ion_page_pool_remove(pool, true);
 		else if (pool->low_count)
-			page = ion_page_pool_remove(pool, false, false);
+			page = ion_page_pool_remove(pool, false);
 		mutex_unlock(&pool->mutex);
 	}
 	if (!page) {
@@ -120,27 +108,6 @@ void *ion_page_pool_alloc(struct ion_page_pool *pool, bool *from_pool)
 	return page;
 }
 
-void *ion_page_pool_prefetch(struct ion_page_pool *pool, bool *from_pool)
-{
-	struct page *page = NULL;
-
-	BUG_ON(!pool);
-
-	*from_pool = true;
-
-	if (mutex_trylock(&pool->mutex)) {
-		if (pool->high_count && pool->nr_unreserved > 0)
-			page = ion_page_pool_remove(pool, true, true);
-		else if (pool->low_count && pool->nr_unreserved > 0)
-			page = ion_page_pool_remove(pool, false, true);
-		mutex_unlock(&pool->mutex);
-	}
-	if (!page) {
-		page = ion_page_pool_alloc_pages(pool);
-		*from_pool = false;
-	}
-	return page;
-}
 /*
  * Tries to allocate from only the specified Pool and returns NULL otherwise
  */
@@ -152,24 +119,22 @@ void *ion_page_pool_alloc_pool_only(struct ion_page_pool *pool)
 
 	if (mutex_trylock(&pool->mutex)) {
 		if (pool->high_count)
-			page = ion_page_pool_remove(pool, true, false);
+			page = ion_page_pool_remove(pool, true);
 		else if (pool->low_count)
-			page = ion_page_pool_remove(pool, false, false);
+			page = ion_page_pool_remove(pool, false);
 		mutex_unlock(&pool->mutex);
 	}
 
 	return page;
 }
 
-void ion_page_pool_free(struct ion_page_pool *pool, struct page *page,
+void ion_page_pool_free(struct ion_page_pool *pool, struct page *page)
-			bool prefetch)
 {
 	int ret;
 
 	BUG_ON(pool->order != compound_order(page));
 
-	ret = ion_page_pool_add(pool, page, prefetch);
+	ret = ion_page_pool_add(pool, page);
-	/* FIXME? For a secure page, not hyp unassigned in this err path */
 	if (ret)
 		ion_page_pool_free_pages(pool, page);
 }
@@ -208,9 +173,9 @@ int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask,
 
 		mutex_lock(&pool->mutex);
 		if (pool->low_count) {
-			page = ion_page_pool_remove(pool, false, false);
+			page = ion_page_pool_remove(pool, false);
 		} else if (high && pool->high_count) {
-			page = ion_page_pool_remove(pool, true, false);
+			page = ion_page_pool_remove(pool, true);
 		} else {
 			mutex_unlock(&pool->mutex);
 			break;
@@ -233,7 +198,6 @@ struct ion_page_pool *ion_page_pool_create(struct device *dev, gfp_t gfp_mask,
 	pool->dev = dev;
 	pool->high_count = 0;
 	pool->low_count = 0;
-	pool->nr_unreserved = 0;
 	INIT_LIST_HEAD(&pool->low_items);
 	INIT_LIST_HEAD(&pool->high_items);
 	pool->gfp_mask = gfp_mask | __GFP_COMP;

drivers/staging/android/ion/ion_priv.h

@@ -415,8 +415,6 @@ void ion_carveout_free(struct ion_heap *heap, ion_phys_addr_t addr,
  * struct ion_page_pool - pagepool struct
  * @high_count:		number of highmem items in the pool
  * @low_count:		number of lowmem items in the pool
- * @nr_unreserved:	number of items in the pool which have not been reserved
- *			by a prefetch allocation
  * @high_items:		list of highmem items
  * @low_items:		list of lowmem items
  * @mutex:		lock protecting this struct and especially the count
@@ -433,7 +431,6 @@ void ion_carveout_free(struct ion_heap *heap, ion_phys_addr_t addr,
 struct ion_page_pool {
 	int high_count;
 	int low_count;
-	int nr_unreserved;
 	struct list_head high_items;
 	struct list_head low_items;
 	struct mutex mutex;
@@ -448,10 +445,9 @@ struct ion_page_pool *ion_page_pool_create(struct device *dev, gfp_t gfp_mask,
 void ion_page_pool_destroy(struct ion_page_pool *);
 void *ion_page_pool_alloc(struct ion_page_pool *, bool *from_pool);
 void *ion_page_pool_alloc_pool_only(struct ion_page_pool *);
-void ion_page_pool_free(struct ion_page_pool *, struct page *, bool prefetch);
+void ion_page_pool_free(struct ion_page_pool *, struct page *);
 void ion_page_pool_free_immediate(struct ion_page_pool *, struct page *);
 int ion_page_pool_total(struct ion_page_pool *pool, bool high);
-void *ion_page_pool_prefetch(struct ion_page_pool *pool, bool *from_pool);
 
 #ifdef CONFIG_ION_POOL_CACHE_POLICY
 static inline void ion_page_pool_alloc_set_cache_policy

drivers/staging/android/ion/ion_system_heap.c

@@ -78,7 +78,6 @@ static struct page *alloc_buffer_page(struct ion_system_heap *heap,
 				      bool *from_pool)
 {
 	bool cached = ion_buffer_cached(buffer);
-	bool prefetch = buffer->flags & ION_FLAG_POOL_PREFETCH;
 	struct page *page;
 	struct ion_page_pool *pool;
 	int vmid = get_secure_vmid(buffer->flags);
@@ -92,10 +91,7 @@ static struct page *alloc_buffer_page(struct ion_system_heap *heap,
 		else
 			pool = heap->cached_pools[order_to_index(order)];
 
-		if (prefetch)
+		page = ion_page_pool_alloc(pool, from_pool);
-			page = ion_page_pool_prefetch(pool, from_pool);
-		else
-			page = ion_page_pool_alloc(pool, from_pool);
 	} else {
 		gfp_t gfp_mask = low_order_gfp_flags;
 		if (order)
@@ -119,7 +115,6 @@ static void free_buffer_page(struct ion_system_heap *heap,
 			     unsigned int order)
 {
 	bool cached = ion_buffer_cached(buffer);
-	bool prefetch = buffer->flags & ION_FLAG_POOL_PREFETCH;
 	int vmid = get_secure_vmid(buffer->flags);
 
 	if (!(buffer->flags & ION_FLAG_POOL_FORCE_ALLOC)) {
@@ -134,7 +129,7 @@ static void free_buffer_page(struct ion_system_heap *heap,
 		if (buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE)
 			ion_page_pool_free_immediate(pool, page);
 		else
-			ion_page_pool_free(pool, page, prefetch);
+			ion_page_pool_free(pool, page);
 	} else {
 		__free_pages(page, order);
 	}
@@ -452,7 +447,7 @@ out1:
 	/* Restore pages to secure pool */
 	list_for_each_entry_safe(page, tmp, &pages, lru) {
 		list_del(&page->lru);
-		ion_page_pool_free(pool, page, false);
+		ion_page_pool_free(pool, page);
 	}
 	return 0;
 out2:

drivers/staging/android/ion/ion_system_secure_heap.c

@@ -151,8 +151,7 @@ static void ion_system_secure_heap_prefetch_work(struct work_struct *work)
 
 		/* buffer->heap used by free() */
 		buffer->heap = &secure_heap->heap;
-		buffer->flags = ION_FLAG_POOL_PREFETCH;
+		buffer->flags = vmid_flags;
-		buffer->flags |= vmid_flags;
 		ret = sys_heap->ops->allocate(sys_heap, buffer, size,
 						PAGE_SIZE, 0);
 		if (ret) {

drivers/staging/android/uapi/msm_ion.h

@@ -110,8 +110,6 @@ enum cp_mem_usage {
  */
 #define ION_FLAG_POOL_FORCE_ALLOC (1 << 16)
 
-#define ION_FLAG_POOL_PREFETCH (1 << 27)
-
 /**
 * Deprecated! Please use the corresponding ION_FLAG_*
 */