[PATCH] LIB: add gen_pool_destroy()

Modules using the genpool allocator need to be able to destroy the data
structure when unloading.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Dean Nelson <dcn@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 31 insertions, 0 deletions

diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h
index 690c42803d2e..9869ef3674ac 100644
--- a/include/linux/genalloc.h
+++ b/include/linux/genalloc.h
@@ -31,5 +31,6 @@ struct gen_pool_chunk {
 
 extern struct gen_pool *gen_pool_create(int, int);
 extern int gen_pool_add(struct gen_pool *, unsigned long, size_t, int);
+extern void gen_pool_destroy(struct gen_pool *);
 extern unsigned long gen_pool_alloc(struct gen_pool *, size_t);
 extern void gen_pool_free(struct gen_pool *, unsigned long, size_t);
diff --git a/lib/genalloc.c b/lib/genalloc.c
index 71338b48e889..7d16ecabba96 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -71,6 +71,36 @@ EXPORT_SYMBOL(gen_pool_add);
 
 
 /*
+ * Destroy a memory pool. Verifies that there are no outstanding allocations.
+ *
+ * @pool: pool to destroy
+ */
+void gen_pool_destroy(struct gen_pool *pool)
+{
+        struct list_head *_chunk, *_next_chunk;
+        struct gen_pool_chunk *chunk;
+        int order = pool->min_alloc_order;
+        int bit, end_bit;
+
+
+        write_lock(&pool->lock);
+        list_for_each_safe(_chunk, _next_chunk, &pool->chunks) {
+                chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk);
+                list_del(&chunk->next_chunk);
+
+                end_bit = (chunk->end_addr - chunk->start_addr) >> order;
+                bit = find_next_bit(chunk->bits, end_bit, 0);
+                BUG_ON(bit < end_bit);
+
+                kfree(chunk);
+        }
+        kfree(pool);
+        return;
+}
+EXPORT_SYMBOL(gen_pool_destroy);
+
+
+/*
  * Allocate the requested number of bytes from the specified pool.
  * Uses a first-fit algorithm.
  *