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-rw-r--r--mm/zbud.c235
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");
}