[PATCH 3/5] lockdep: Apply bit_spin_lock lockdep to zram

[Byungchul Park]

In order to use lockdep-enabled bit_spin_lock, we have to call
bit_spin_init() when a instance including the bit used as lock
creates, and bit_spin_free() when the instance including the bit
destroys.

The zram is one of bit_spin_lock users. And this patch adds
bit_spin_init() and bit_spin_free() properly to apply the lock
correctness validator to bit_spin_lock the rzam is using.

Signed-off-by: Byungchul Park <byungchul.park@xxxxxxx>
---
 drivers/block/zram/zram_drv.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 370c2f7..2bc3bde 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -495,6 +495,11 @@ static void zram_meta_free(struct zram_meta *meta, u64 disksize)
 	}
 
 	zs_destroy_pool(meta->mem_pool);
+
+	for (index = 0; index < num_pages; index++) {
+		bit_spin_free(ZRAM_ACCESS, &meta->table[index].value);
+	}
+
 	vfree(meta->table);
 	kfree(meta);
 }
@@ -503,6 +508,7 @@ static struct zram_meta *zram_meta_alloc(char *pool_name, u64 disksize)
 {
 	size_t num_pages;
 	struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL);
+	int index;
 
 	if (!meta)
 		return NULL;
@@ -520,6 +526,10 @@ static struct zram_meta *zram_meta_alloc(char *pool_name, u64 disksize)
 		goto out_error;
 	}
 
+	for (index = 0; index < num_pages; index++) {
+		bit_spin_init(ZRAM_ACCESS, &meta->table[index].value);
+	}
+
 	return meta;
 
 out_error:
-- 
1.9.1