1 files changed, 119 insertions, 116 deletions

diff --git a/mm/zbud.c b/mm/zbud.c
index 7ec5f27a68b0..6348932430b8 100644
--- a/mm/zbud.c
+++ b/mm/zbud.c
@@ -51,7 +51,6 @@
 #include <linux/preempt.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
-#include <linux/zbud.h>
 #include <linux/zpool.h>
 
 /*****************
@@ -73,6 +72,12 @@
 #define ZHDR_SIZE_ALIGNED CHUNK_SIZE
 #define NCHUNKS		((PAGE_SIZE - ZHDR_SIZE_ALIGNED) >> CHUNK_SHIFT)
 
+struct zbud_pool;
+
+struct zbud_ops {
+	int (*evict)(struct zbud_pool *pool, unsigned long handle);
+};
+
 /**
  * struct zbud_pool - stores metadata for each zbud pool
  * @lock:	protects all pool fields and first|last_chunk fields of any
@@ -87,21 +92,27 @@
  * @pages_nr:	number of zbud pages in the pool.
  * @ops:	pointer to a structure of user defined operations specified at
  *		pool creation time.
+ * @zpool:	zpool driver
+ * @zpool_ops:	zpool operations structure with an evict callback
  *
  * This structure is allocated at pool creation time and maintains metadata
  * pertaining to a particular zbud pool.
  */
 struct zbud_pool {
 	spinlock_t lock;
-	struct list_head unbuddied[NCHUNKS];
-	struct list_head buddied;
+	union {
+		/*
+		 * Reuse unbuddied[0] as buddied on the ground that
+		 * unbuddied[0] is unused.
+		 */
+		struct list_head buddied;
+		struct list_head unbuddied[NCHUNKS];
+	};
 	struct list_head lru;
 	u64 pages_nr;
 	const struct zbud_ops *ops;
-#ifdef CONFIG_ZPOOL
 	struct zpool *zpool;
 	const struct zpool_ops *zpool_ops;
-#endif
 };
 
 /*
@@ -121,104 +132,6 @@ struct zbud_header {
 };
 
 /*****************
- * zpool
- ****************/
-
-#ifdef CONFIG_ZPOOL
-
-static int zbud_zpool_evict(struct zbud_pool *pool, unsigned long handle)
-{
-	if (pool->zpool && pool->zpool_ops && pool->zpool_ops->evict)
-		return pool->zpool_ops->evict(pool->zpool, handle);
-	else
-		return -ENOENT;
-}
-
-static const struct zbud_ops zbud_zpool_ops = {
-	.evict =	zbud_zpool_evict
-};
-
-static void *zbud_zpool_create(const char *name, gfp_t gfp,
-			       const struct zpool_ops *zpool_ops,
-			       struct zpool *zpool)
-{
-	struct zbud_pool *pool;
-
-	pool = zbud_create_pool(gfp, zpool_ops ? &zbud_zpool_ops : NULL);
-	if (pool) {
-		pool->zpool = zpool;
-		pool->zpool_ops = zpool_ops;
-	}
-	return pool;
-}
-
-static void zbud_zpool_destroy(void *pool)
-{
-	zbud_destroy_pool(pool);
-}
-
-static int zbud_zpool_malloc(void *pool, size_t size, gfp_t gfp,
-			unsigned long *handle)
-{
-	return zbud_alloc(pool, size, gfp, handle);
-}
-static void zbud_zpool_free(void *pool, unsigned long handle)
-{
-	zbud_free(pool, handle);
-}
-
-static int zbud_zpool_shrink(void *pool, unsigned int pages,
-			unsigned int *reclaimed)
-{
-	unsigned int total = 0;
-	int ret = -EINVAL;
-
-	while (total < pages) {
-		ret = zbud_reclaim_page(pool, 8);
-		if (ret < 0)
-			break;
-		total++;
-	}
-
-	if (reclaimed)
-		*reclaimed = total;
-
-	return ret;
-}
-
-static void *zbud_zpool_map(void *pool, unsigned long handle,
-			enum zpool_mapmode mm)
-{
-	return zbud_map(pool, handle);
-}
-static void zbud_zpool_unmap(void *pool, unsigned long handle)
-{
-	zbud_unmap(pool, handle);
-}
-
-static u64 zbud_zpool_total_size(void *pool)
-{
-	return zbud_get_pool_size(pool) * PAGE_SIZE;
-}
-
-static struct zpool_driver zbud_zpool_driver = {
-	.type =		"zbud",
-	.sleep_mapped = true,
-	.owner =	THIS_MODULE,
-	.create =	zbud_zpool_create,
-	.destroy =	zbud_zpool_destroy,
-	.malloc =	zbud_zpool_malloc,
-	.free =		zbud_zpool_free,
-	.shrink =	zbud_zpool_shrink,
-	.map =		zbud_zpool_map,
-	.unmap =	zbud_zpool_unmap,
-	.total_size =	zbud_zpool_total_size,
-};
-
-MODULE_ALIAS("zpool-zbud");
-#endif /* CONFIG_ZPOOL */
-
-/*****************
  * Helpers
 *****************/
 /* Just to make the code easier to read */
@@ -304,7 +217,7 @@ static int num_free_chunks(struct zbud_header *zhdr)
  * Return: pointer to the new zbud pool or NULL if the metadata allocation
  * failed.
  */
-struct zbud_pool *zbud_create_pool(gfp_t gfp, const struct zbud_ops *ops)
+static struct zbud_pool *zbud_create_pool(gfp_t gfp, const struct zbud_ops *ops)
 {
 	struct zbud_pool *pool;
 	int i;
@@ -328,7 +241,7 @@ struct zbud_pool *zbud_create_pool(gfp_t gfp, const struct zbud_ops *ops)
  *
  * The pool should be emptied before this function is called.
  */
-void zbud_destroy_pool(struct zbud_pool *pool)
+static void zbud_destroy_pool(struct zbud_pool *pool)
 {
 	kfree(pool);
 }
@@ -352,7 +265,7 @@ void zbud_destroy_pool(struct zbud_pool *pool)
  * gfp arguments are invalid or -ENOMEM if the pool was unable to allocate
  * a new page.
  */
-int zbud_alloc(struct zbud_pool *pool, size_t size, gfp_t gfp,
+static int zbud_alloc(struct zbud_pool *pool, size_t size, gfp_t gfp,
 			unsigned long *handle)
 {
 	int chunks, i, freechunks;
@@ -427,7 +340,7 @@ found:
  * only sets the first|last_chunks to 0.  The page is actually freed
  * once both buddies are evicted (see zbud_reclaim_page() below).
  */
-void zbud_free(struct zbud_pool *pool, unsigned long handle)
+static void zbud_free(struct zbud_pool *pool, unsigned long handle)
 {
 	struct zbud_header *zhdr;
 	int freechunks;
@@ -499,7 +412,7 @@ void zbud_free(struct zbud_pool *pool, unsigned long handle)
  * no pages to evict or an eviction handler is not registered, -EAGAIN if
  * the retry limit was hit.
  */
-int zbud_reclaim_page(struct zbud_pool *pool, unsigned int retries)
+static int zbud_reclaim_page(struct zbud_pool *pool, unsigned int retries)
 {
 	int i, ret, freechunks;
 	struct zbud_header *zhdr;
@@ -581,7 +494,7 @@ next:
  *
  * Returns: a pointer to the mapped allocation
  */
-void *zbud_map(struct zbud_pool *pool, unsigned long handle)
+static void *zbud_map(struct zbud_pool *pool, unsigned long handle)
 {
 	return (void *)(handle);
 }
@@ -591,7 +504,7 @@ void *zbud_map(struct zbud_pool *pool, unsigned long handle)
  * @pool:	pool in which the allocation resides
  * @handle:	handle associated with the allocation to be unmapped
  */
-void zbud_unmap(struct zbud_pool *pool, unsigned long handle)
+static void zbud_unmap(struct zbud_pool *pool, unsigned long handle)
 {
 }
 
@@ -602,30 +515,120 @@ void zbud_unmap(struct zbud_pool *pool, unsigned long handle)
  * Returns: size in pages of the given pool.  The pool lock need not be
  * taken to access pages_nr.
  */
-u64 zbud_get_pool_size(struct zbud_pool *pool)
+static u64 zbud_get_pool_size(struct zbud_pool *pool)
 {
 	return pool->pages_nr;
 }
 
+/*****************
+ * zpool
+ ****************/
+
+static int zbud_zpool_evict(struct zbud_pool *pool, unsigned long handle)
+{
+	if (pool->zpool && pool->zpool_ops && pool->zpool_ops->evict)
+		return pool->zpool_ops->evict(pool->zpool, handle);
+	else
+		return -ENOENT;
+}
+
+static const struct zbud_ops zbud_zpool_ops = {
+	.evict =	zbud_zpool_evict
+};
+
+static void *zbud_zpool_create(const char *name, gfp_t gfp,
+			       const struct zpool_ops *zpool_ops,
+			       struct zpool *zpool)
+{
+	struct zbud_pool *pool;
+
+	pool = zbud_create_pool(gfp, zpool_ops ? &zbud_zpool_ops : NULL);
+	if (pool) {
+		pool->zpool = zpool;
+		pool->zpool_ops = zpool_ops;
+	}
+	return pool;
+}
+
+static void zbud_zpool_destroy(void *pool)
+{
+	zbud_destroy_pool(pool);
+}
+
+static int zbud_zpool_malloc(void *pool, size_t size, gfp_t gfp,
+			unsigned long *handle)
+{
+	return zbud_alloc(pool, size, gfp, handle);
+}
+static void zbud_zpool_free(void *pool, unsigned long handle)
+{
+	zbud_free(pool, handle);
+}
+
+static int zbud_zpool_shrink(void *pool, unsigned int pages,
+			unsigned int *reclaimed)
+{
+	unsigned int total = 0;
+	int ret = -EINVAL;
+
+	while (total < pages) {
+		ret = zbud_reclaim_page(pool, 8);
+		if (ret < 0)
+			break;
+		total++;
+	}
+
+	if (reclaimed)
+		*reclaimed = total;
+
+	return ret;
+}
+
+static void *zbud_zpool_map(void *pool, unsigned long handle,
+			enum zpool_mapmode mm)
+{
+	return zbud_map(pool, handle);
+}
+static void zbud_zpool_unmap(void *pool, unsigned long handle)
+{
+	zbud_unmap(pool, handle);
+}
+
+static u64 zbud_zpool_total_size(void *pool)
+{
+	return zbud_get_pool_size(pool) * PAGE_SIZE;
+}
+
+static struct zpool_driver zbud_zpool_driver = {
+	.type =		"zbud",
+	.sleep_mapped = true,
+	.owner =	THIS_MODULE,
+	.create =	zbud_zpool_create,
+	.destroy =	zbud_zpool_destroy,
+	.malloc =	zbud_zpool_malloc,
+	.free =		zbud_zpool_free,
+	.shrink =	zbud_zpool_shrink,
+	.map =		zbud_zpool_map,
+	.unmap =	zbud_zpool_unmap,
+	.total_size =	zbud_zpool_total_size,
+};
+
+MODULE_ALIAS("zpool-zbud");
+
 static int __init init_zbud(void)
 {
 	/* Make sure the zbud header will fit in one chunk */
 	BUILD_BUG_ON(sizeof(struct zbud_header) > ZHDR_SIZE_ALIGNED);
 	pr_info("loaded\n");
 
-#ifdef CONFIG_ZPOOL
 	zpool_register_driver(&zbud_zpool_driver);
-#endif
 
 	return 0;
 }
 
 static void __exit exit_zbud(void)
 {
-#ifdef CONFIG_ZPOOL
 	zpool_unregister_driver(&zbud_zpool_driver);
-#endif
-
 	pr_info("unloaded\n");
 }