linux-stable/include/linux/mempool.h
David Rientjes e244c9e66f mm, mempool: disallow mempools based on slab caches with constructors
All occurrences of mempools based on slab caches with object constructors
have been removed from the tree, so disallow creating them.

We can only dereference mem->ctor in mm/mempool.c without including
mm/slab.h in include/linux/mempool.h.  So simply note the restriction,
just like the comment restricting usage of __GFP_ZERO, and warn on kernels
with CONFIG_DEBUG_VM() if such a mempool is allocated from.

We don't want to incur this check on every element allocation, so use
VM_BUG_ON().

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:18 -07:00

75 lines
2.3 KiB
C

/*
* memory buffer pool support
*/
#ifndef _LINUX_MEMPOOL_H
#define _LINUX_MEMPOOL_H
#include <linux/wait.h>
struct kmem_cache;
typedef void * (mempool_alloc_t)(gfp_t gfp_mask, void *pool_data);
typedef void (mempool_free_t)(void *element, void *pool_data);
typedef struct mempool_s {
spinlock_t lock;
int min_nr; /* nr of elements at *elements */
int curr_nr; /* Current nr of elements at *elements */
void **elements;
void *pool_data;
mempool_alloc_t *alloc;
mempool_free_t *free;
wait_queue_head_t wait;
} mempool_t;
extern mempool_t *mempool_create(int min_nr, mempool_alloc_t *alloc_fn,
mempool_free_t *free_fn, void *pool_data);
extern mempool_t *mempool_create_node(int min_nr, mempool_alloc_t *alloc_fn,
mempool_free_t *free_fn, void *pool_data,
gfp_t gfp_mask, int nid);
extern int mempool_resize(mempool_t *pool, int new_min_nr);
extern void mempool_destroy(mempool_t *pool);
extern void * mempool_alloc(mempool_t *pool, gfp_t gfp_mask);
extern void mempool_free(void *element, mempool_t *pool);
/*
* A mempool_alloc_t and mempool_free_t that get the memory from
* a slab cache that is passed in through pool_data.
* Note: the slab cache may not have a ctor function.
*/
void *mempool_alloc_slab(gfp_t gfp_mask, void *pool_data);
void mempool_free_slab(void *element, void *pool_data);
static inline mempool_t *
mempool_create_slab_pool(int min_nr, struct kmem_cache *kc)
{
return mempool_create(min_nr, mempool_alloc_slab, mempool_free_slab,
(void *) kc);
}
/*
* a mempool_alloc_t and a mempool_free_t to kmalloc and kfree the
* amount of memory specified by pool_data
*/
void *mempool_kmalloc(gfp_t gfp_mask, void *pool_data);
void mempool_kfree(void *element, void *pool_data);
static inline mempool_t *mempool_create_kmalloc_pool(int min_nr, size_t size)
{
return mempool_create(min_nr, mempool_kmalloc, mempool_kfree,
(void *) size);
}
/*
* A mempool_alloc_t and mempool_free_t for a simple page allocator that
* allocates pages of the order specified by pool_data
*/
void *mempool_alloc_pages(gfp_t gfp_mask, void *pool_data);
void mempool_free_pages(void *element, void *pool_data);
static inline mempool_t *mempool_create_page_pool(int min_nr, int order)
{
return mempool_create(min_nr, mempool_alloc_pages, mempool_free_pages,
(void *)(long)order);
}
#endif /* _LINUX_MEMPOOL_H */