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authorJiri Kosina2014-11-20 14:42:02 +0100
committerJiri Kosina2014-11-20 14:42:02 +0100
commita02001086bbfb4da35d1228bebc2f1b442db455f (patch)
tree62ab47936cef06fd08657ca5b6cd1df98c19be57 /mm/zbud.c
parenteff264efeeb0898408e8c9df72d8a32621035bed (diff)
parentfc14f9c1272f62c3e8d01300f52467c0d9af50f9 (diff)
Merge Linus' tree to be be to apply submitted patches to newer code than
current trivial.git base
Diffstat (limited to 'mm/zbud.c')
-rw-r--r--mm/zbud.c112
1 files changed, 104 insertions, 8 deletions
diff --git a/mm/zbud.c b/mm/zbud.c
index bf424047060f..ec71b37fb06c 100644
--- a/mm/zbud.c
+++ b/mm/zbud.c
@@ -51,6 +51,7 @@
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/zbud.h>
+#include <linux/zpool.h>
/*****************
* Structures
@@ -59,15 +60,17 @@
* NCHUNKS_ORDER determines the internal allocation granularity, effectively
* adjusting internal fragmentation. It also determines the number of
* freelists maintained in each pool. NCHUNKS_ORDER of 6 means that the
- * allocation granularity will be in chunks of size PAGE_SIZE/64, and there
- * will be 64 freelists per pool.
+ * allocation granularity will be in chunks of size PAGE_SIZE/64. As one chunk
+ * in allocated page is occupied by zbud header, NCHUNKS will be calculated to
+ * 63 which shows the max number of free chunks in zbud page, also there will be
+ * 63 freelists per pool.
*/
#define NCHUNKS_ORDER 6
#define CHUNK_SHIFT (PAGE_SHIFT - NCHUNKS_ORDER)
#define CHUNK_SIZE (1 << CHUNK_SHIFT)
-#define NCHUNKS (PAGE_SIZE >> CHUNK_SHIFT)
#define ZHDR_SIZE_ALIGNED CHUNK_SIZE
+#define NCHUNKS ((PAGE_SIZE - ZHDR_SIZE_ALIGNED) >> CHUNK_SHIFT)
/**
* struct zbud_pool - stores metadata for each zbud pool
@@ -113,6 +116,91 @@ struct zbud_header {
};
/*****************
+ * zpool
+ ****************/
+
+#ifdef CONFIG_ZPOOL
+
+static int zbud_zpool_evict(struct zbud_pool *pool, unsigned long handle)
+{
+ return zpool_evict(pool, handle);
+}
+
+static struct zbud_ops zbud_zpool_ops = {
+ .evict = zbud_zpool_evict
+};
+
+static void *zbud_zpool_create(gfp_t gfp, struct zpool_ops *zpool_ops)
+{
+ return zbud_create_pool(gfp, &zbud_zpool_ops);
+}
+
+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",
+ .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 */
@@ -122,7 +210,7 @@ enum buddy {
};
/* Converts an allocation size in bytes to size in zbud chunks */
-static int size_to_chunks(int size)
+static int size_to_chunks(size_t size)
{
return (size + CHUNK_SIZE - 1) >> CHUNK_SHIFT;
}
@@ -182,10 +270,9 @@ static int num_free_chunks(struct zbud_header *zhdr)
{
/*
* Rather than branch for different situations, just use the fact that
- * free buddies have a length of zero to simplify everything. -1 at the
- * end for the zbud header.
+ * free buddies have a length of zero to simplify everything.
*/
- return NCHUNKS - zhdr->first_chunks - zhdr->last_chunks - 1;
+ return NCHUNKS - zhdr->first_chunks - zhdr->last_chunks;
}
/*****************
@@ -247,7 +334,7 @@ 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, unsigned int size, gfp_t gfp,
+int zbud_alloc(struct zbud_pool *pool, size_t size, gfp_t gfp,
unsigned long *handle)
{
int chunks, i, freechunks;
@@ -511,11 +598,20 @@ 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");
}