mempool: kvmalloc pool

Add mempool_init_kvmalloc_pool() and mempool_create_kvmalloc_pool(),
which wrap kvmalloc() instead of kmalloc() - kmalloc() with a vmalloc()
fallback.

This is part of a bcachefs cleanup - dropping an internal kvpmalloc()
helper (which predates kvmalloc()) along with mempool helpers; this
replaces the bcachefs-private kvpmalloc_pool.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Cc: linux-mm@kvack.org

1 files changed, 13 insertions, 0 deletions

diff --git a/include/linux/mempool.h b/include/linux/mempool.h
index 7be1e32e6d42..16c5cc807ff6 100644
--- a/include/linux/mempool.h
+++ b/include/linux/mempool.h
@@ -95,6 +95,19 @@ static inline mempool_t *mempool_create_kmalloc_pool(int min_nr, size_t size)
 			      (void *) size);
 }
 
+void *mempool_kvmalloc(gfp_t gfp_mask, void *pool_data);
+void mempool_kvfree(void *element, void *pool_data);
+
+static inline int mempool_init_kvmalloc_pool(mempool_t *pool, int min_nr, size_t size)
+{
+	return mempool_init(pool, min_nr, mempool_kvmalloc, mempool_kvfree, (void *) size);
+}
+
+static inline mempool_t *mempool_create_kvmalloc_pool(int min_nr, size_t size)
+{
+	return mempool_create(min_nr, mempool_kvmalloc, mempool_kvfree, (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