This patch allows a zsmalloc user to define the page
allocation and free functions to be used when growing
or releasing parts of the memory pool.
The functions are passed in the struct zs_pool_ops parameter
of zs_create_pool() at pool creation time. If this parameter
is NULL, zsmalloc uses alloc_page and __free_page() by default.
While there is no current user of this functionality, zcache
development plans to make use of it in the near future.
Patch applies to Greg's staging-next branch.
Signed-off-by: Seth Jennings <sjenning@xxxxxxxxxxxxxxxxxx>
---
drivers/staging/zcache/zcache-main.c | 2 +-
drivers/staging/zram/zram_drv.c | 3 +-
drivers/staging/zsmalloc/zsmalloc-main.c | 39 +++++++++++++++++++++++-------
drivers/staging/zsmalloc/zsmalloc.h | 8 +++++-
drivers/staging/zsmalloc/zsmalloc_int.h | 2 +
5 files changed, 42 insertions(+), 12 deletions(-)
diff --git a/drivers/staging/zcache/zcache-main.c b/drivers/staging/zcache/zcache-main.c
index b698464..7ef5313 100644
--- a/drivers/staging/zcache/zcache-main.c
+++ b/drivers/staging/zcache/zcache-main.c
@@ -984,7 +984,7 @@ int zcache_new_client(uint16_t cli_id)
goto out;
cli->allocated = 1;
#ifdef CONFIG_FRONTSWAP
- cli->zspool = zs_create_pool("zcache", ZCACHE_GFP_MASK);
+ cli->zspool = zs_create_pool("zcache", ZCACHE_GFP_MASK, NULL);
if (cli->zspool == NULL)
goto out;
#endif
diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c
index 7f13819..278eb4d 100644
--- a/drivers/staging/zram/zram_drv.c
+++ b/drivers/staging/zram/zram_drv.c
@@ -663,7 +663,8 @@ int zram_init_device(struct zram *zram)
/* zram devices sort of resembles non-rotational disks */
queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue);
- zram->mem_pool = zs_create_pool("zram", GFP_NOIO | __GFP_HIGHMEM);
+ zram->mem_pool = zs_create_pool("zram", GFP_NOIO | __GFP_HIGHMEM,
+ NULL);
if (!zram->mem_pool) {
pr_err("Error creating memory pool\n");
ret = -ENOMEM;
diff --git a/drivers/staging/zsmalloc/zsmalloc-main.c b/drivers/staging/zsmalloc/zsmalloc-main.c
index 09caa4f..c8bfb77 100644
--- a/drivers/staging/zsmalloc/zsmalloc-main.c
+++ b/drivers/staging/zsmalloc/zsmalloc-main.c
@@ -267,7 +267,7 @@ static unsigned long obj_idx_to_offset(struct page *page,
return off + obj_idx * class_size;
}
-static void free_zspage(struct page *first_page)
+static void free_zspage(struct zs_pool *pool, struct page *first_page)
{
struct page *nextp, *tmp;
@@ -282,7 +282,7 @@ static void free_zspage(struct page *first_page)
first_page->mapping = NULL;
first_page->freelist = NULL;
reset_page_mapcount(first_page);
- __free_page(first_page);
+ (*pool->ops->free_page)(first_page);
/* zspage with only 1 system page */
if (!nextp)
@@ -345,7 +345,7 @@ static void init_zspage(struct page *first_page, struct size_class *class)
/*
* Allocate a zspage for the given size class
*/
-static struct page *alloc_zspage(struct size_class *class, gfp_t flags)
+static struct page *alloc_zspage(struct zs_pool *pool, struct size_class *class)
{
int i, error;
struct page *first_page = NULL;
@@ -365,7 +365,7 @@ static struct page *alloc_zspage(struct size_class *class, gfp_t flags)
for (i = 0; i < class->zspage_order; i++) {
struct page *page, *prev_page;
- page = alloc_page(flags);
+ page = (*pool->ops->alloc_page)(pool->flags);
if (!page)
goto cleanup;
@@ -398,7 +398,7 @@ static struct page *alloc_zspage(struct size_class *class, gfp_t flags)
cleanup:
if (unlikely(error) && first_page) {
- free_zspage(first_page);
+ free_zspage(pool, first_page);
first_page = NULL;
}
@@ -482,7 +482,24 @@ fail:
return notifier_to_errno(ret);
}
-struct zs_pool *zs_create_pool(const char *name, gfp_t flags)
+
+static inline struct page *zs_alloc_page(gfp_t flags)
+{
+ return alloc_page(flags);
+}
+
+static inline void zs_free_page(struct page *page)
+{
+ __free_page(page);
+}
+
+static struct zs_pool_ops default_ops = {
+ .alloc_page = zs_alloc_page,
+ .free_page = zs_free_page
+};
+
+struct zs_pool *zs_create_pool(const char *name, gfp_t flags,
+ struct zs_pool_ops *ops)
{
int i, error, ovhd_size;
struct zs_pool *pool;
@@ -492,7 +509,7 @@ struct zs_pool *zs_create_pool(const char *name, gfp_t flags)
ovhd_size = roundup(sizeof(*pool), PAGE_SIZE);
pool = kzalloc(ovhd_size, GFP_KERNEL);
- if (!pool)
+ if (!pool || (ops && (!ops->alloc_page || !ops->free_page)))
return NULL;
for (i = 0; i < ZS_SIZE_CLASSES; i++) {
@@ -524,6 +541,10 @@ struct zs_pool *zs_create_pool(const char *name, gfp_t flags)
pool->flags = flags;
pool->name = name;
+ if (ops)
+ pool->ops = ops;
+ else
+ pool->ops = &default_ops;
error = 0; /* Success */
@@ -592,7 +613,7 @@ void *zs_malloc(struct zs_pool *pool, size_t size)
if (!first_page) {
spin_unlock(&class->lock);
- first_page = alloc_zspage(class, pool->flags);
+ first_page = alloc_zspage(pool, class);
if (unlikely(!first_page))
return NULL;
@@ -658,7 +679,7 @@ void zs_free(struct zs_pool *pool, void *obj)
spin_unlock(&class->lock);
if (fullness == ZS_EMPTY)
- free_zspage(first_page);
+ free_zspage(pool, first_page);
}
EXPORT_SYMBOL_GPL(zs_free);
diff --git a/drivers/staging/zsmalloc/zsmalloc.h b/drivers/staging/zsmalloc/zsmalloc.h
index 949384e..51fb32e 100644
--- a/drivers/staging/zsmalloc/zsmalloc.h
+++ b/drivers/staging/zsmalloc/zsmalloc.h
@@ -17,7 +17,13 @@
struct zs_pool;
-struct zs_pool *zs_create_pool(const char *name, gfp_t flags);
+struct zs_pool_ops {
+ struct page * (*alloc_page)(gfp_t);
+ void (*free_page)(struct page *);
+};
+
+struct zs_pool *zs_create_pool(const char *name, gfp_t flags,
+ struct zs_pool_ops *ops);
void zs_destroy_pool(struct zs_pool *pool);
void *zs_malloc(struct zs_pool *pool, size_t size);
diff --git a/drivers/staging/zsmalloc/zsmalloc_int.h b/drivers/staging/zsmalloc/zsmalloc_int.h
index 92eefc6..ade09c1 100644
--- a/drivers/staging/zsmalloc/zsmalloc_int.h
+++ b/drivers/staging/zsmalloc/zsmalloc_int.h
@@ -16,6 +16,7 @@
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/types.h>
+#include "zsmalloc.h"
/*
* This must be power of 2 and greater than of equal to sizeof(link_free).
@@ -146,6 +147,7 @@ struct link_free {
};
struct zs_pool {
+ struct zs_pool_ops *ops;
struct size_class size_class[ZS_SIZE_CLASSES];
gfp_t flags; /* allocation flags used when growing pool */
--
1.7.5.4
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