staging: zsmalloc: zsmalloc: use unsigned long instead of void *
We should use unsigned long as handle instead of void * to avoid any
confusion. Without this, users may just treat zs_malloc return value as
a pointer and try to deference it.
This patch passed compile test(zram, zcache and ramster) and zram is
tested on qemu.
changelog
* from v2
- remove hval pointed out by Nitin
- based on next-20120607
* from v1
- change zcache's zv_create return value
- baesd on next-20120604
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/staging/zsmalloc/zsmalloc-main.c b/drivers/staging/zsmalloc/zsmalloc-main.c
index 4496737..8e830ee 100644
--- a/drivers/staging/zsmalloc/zsmalloc-main.c
+++ b/drivers/staging/zsmalloc/zsmalloc-main.c
@@ -247,13 +247,11 @@
}
/* Decode <page, obj_idx> pair from the given object handle */
-static void obj_handle_to_location(void *handle, struct page **page,
+static void obj_handle_to_location(unsigned long handle, struct page **page,
unsigned long *obj_idx)
{
- unsigned long hval = (unsigned long)handle;
-
- *page = pfn_to_page(hval >> OBJ_INDEX_BITS);
- *obj_idx = hval & OBJ_INDEX_MASK;
+ *page = pfn_to_page(handle >> OBJ_INDEX_BITS);
+ *obj_idx = handle & OBJ_INDEX_MASK;
}
static unsigned long obj_idx_to_offset(struct page *page,
@@ -568,12 +566,12 @@
* @size: size of block to allocate
*
* On success, handle to the allocated object is returned,
- * otherwise NULL.
+ * otherwise 0.
* Allocation requests with size > ZS_MAX_ALLOC_SIZE will fail.
*/
-void *zs_malloc(struct zs_pool *pool, size_t size)
+unsigned long zs_malloc(struct zs_pool *pool, size_t size)
{
- void *obj;
+ unsigned long obj;
struct link_free *link;
int class_idx;
struct size_class *class;
@@ -582,7 +580,7 @@
unsigned long m_objidx, m_offset;
if (unlikely(!size || size > ZS_MAX_ALLOC_SIZE))
- return NULL;
+ return 0;
class_idx = get_size_class_index(size);
class = &pool->size_class[class_idx];
@@ -595,14 +593,14 @@
spin_unlock(&class->lock);
first_page = alloc_zspage(class, pool->flags);
if (unlikely(!first_page))
- return NULL;
+ return 0;
set_zspage_mapping(first_page, class->index, ZS_EMPTY);
spin_lock(&class->lock);
class->pages_allocated += class->pages_per_zspage;
}
- obj = first_page->freelist;
+ obj = (unsigned long)first_page->freelist;
obj_handle_to_location(obj, &m_page, &m_objidx);
m_offset = obj_idx_to_offset(m_page, m_objidx, class->size);
@@ -621,7 +619,7 @@
}
EXPORT_SYMBOL_GPL(zs_malloc);
-void zs_free(struct zs_pool *pool, void *obj)
+void zs_free(struct zs_pool *pool, unsigned long obj)
{
struct link_free *link;
struct page *first_page, *f_page;
@@ -648,7 +646,7 @@
+ f_offset);
link->next = first_page->freelist;
kunmap_atomic(link);
- first_page->freelist = obj;
+ first_page->freelist = (void *)obj;
first_page->inuse--;
fullness = fix_fullness_group(pool, first_page);
@@ -672,7 +670,7 @@
* this function. When done with the object, it must be unmapped using
* zs_unmap_object
*/
-void *zs_map_object(struct zs_pool *pool, void *handle)
+void *zs_map_object(struct zs_pool *pool, unsigned long handle)
{
struct page *page;
unsigned long obj_idx, off;
@@ -712,7 +710,7 @@
}
EXPORT_SYMBOL_GPL(zs_map_object);
-void zs_unmap_object(struct zs_pool *pool, void *handle)
+void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
{
struct page *page;
unsigned long obj_idx, off;