[PATCH] genalloc: add support of named pool

From: Jean-Christophe PLAGNIOL-VILLARD
Date: Thu Dec 08 2011 - 16:19:20 EST


so we can get the pool in the driver by name instead of passing it via
parameter

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@xxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/genalloc.h | 19 ++++++++++++++++++-
lib/genalloc.c | 32 +++++++++++++++++++++++++++++++-
2 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h
index 5e98eeb..38d3efe 100644
--- a/include/linux/genalloc.h
+++ b/include/linux/genalloc.h
@@ -33,9 +33,12 @@
* General purpose special memory pool descriptor.
*/
struct gen_pool {
+ char *name; /* pool name */
spinlock_t lock;
struct list_head chunks; /* list of chunks in this pool */
int min_alloc_order; /* minimum allocation order */
+
+ struct list_head list;
};

/*
@@ -50,7 +53,21 @@ struct gen_pool_chunk {
unsigned long bits[0]; /* bitmap for allocating memory chunk */
};

-extern struct gen_pool *gen_pool_create(int, int);
+extern struct gen_pool *gen_pool_create_byname(char*, int, int);
+
+/**
+ * gen_pool_create - create a new special memory pool
+ * @min_alloc_order: log base 2 of number of bytes each bitmap bit represents
+ * @nid: node id of the node the pool structure should be allocated on, or -1
+ *
+ * Create a new special memory pool that can be used to manage special purpose
+ * memory not managed by the regular kmalloc/kfree interface.
+ */
+static inline struct gen_pool *gen_pool_create(int min_alloc_order, int nid)
+{
+ return gen_pool_create_byname(NULL, min_alloc_order, nid);
+}
+extern struct gen_pool* gen_pool_byname(char *name);
extern phys_addr_t gen_pool_virt_to_phys(struct gen_pool *pool, unsigned long);
extern int gen_pool_add_virt(struct gen_pool *, unsigned long, phys_addr_t,
size_t, int);
diff --git a/lib/genalloc.c b/lib/genalloc.c
index f352cc4..25ec676 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -35,6 +35,8 @@
#include <linux/interrupt.h>
#include <linux/genalloc.h>

+static LIST_HEAD(pools);
+
static int set_bits_ll(unsigned long *addr, unsigned long mask_to_set)
{
unsigned long val, nval;
@@ -136,23 +138,50 @@ static int bitmap_clear_ll(unsigned long *map, int start, int nr)
}

/**
+ * gen_pool_byname - get pool by name
+ * @name: pool name
+ *
+ */
+struct gen_pool* gen_pool_byname(char *name)
+{
+ struct gen_pool *pool;
+
+ if (!name)
+ return NULL;
+
+ list_for_each_entry(pool, &pools, list) {
+ if(pool->name && strcmp(pool->name, name) == 0)
+ return pool;
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL(gen_pool_byname);
+
+/**
* gen_pool_create - create a new special memory pool
+ * @name: pool name if NULL you will not be able to get it via gen_pool_byname
* @min_alloc_order: log base 2 of number of bytes each bitmap bit represents
* @nid: node id of the node the pool structure should be allocated on, or -1
*
* Create a new special memory pool that can be used to manage special purpose
* memory not managed by the regular kmalloc/kfree interface.
*/
-struct gen_pool *gen_pool_create(int min_alloc_order, int nid)
+struct gen_pool *gen_pool_create_byname(char *name, int min_alloc_order, int nid)
{
struct gen_pool *pool;

+ if (gen_pool_byname(name))
+ return NULL;
+
pool = kmalloc_node(sizeof(struct gen_pool), GFP_KERNEL, nid);
if (pool != NULL) {
spin_lock_init(&pool->lock);
INIT_LIST_HEAD(&pool->chunks);
pool->min_alloc_order = min_alloc_order;
}
+
+ list_add_tail(&pool->list, &pools);
return pool;
}
EXPORT_SYMBOL(gen_pool_create);
@@ -244,6 +273,7 @@ void gen_pool_destroy(struct gen_pool *pool)

kfree(chunk);
}
+ list_del(&pool->list);
kfree(pool);
return;
}
--
1.7.7

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/