Staging: ramzswap: Free memory when create_device is failed

If create_device is failed, it can't free gendisk and request_queue of
preceding devices. It cause memory leak.

This patch fixes it.

Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/ramzswap/ramzswap_drv.c b/drivers/staging/ramzswap/ramzswap_drv.c
index 7a7ead4e6c87527bf25ef27062cabc6005f32754..baf757259d0bda4a00d43a5219eada9fd7b297fc 100644 (file)
--- a/drivers/staging/ramzswap/ramzswap_drv.c
+++ b/drivers/staging/ramzswap/ramzswap_drv.c
@@ -1292,7 +1292,7 @@ static struct block_device_operations ramzswap_devops = {
        .owner = THIS_MODULE,
 };
 
-static void create_device(struct ramzswap *rzs, int device_id)
+static int create_device(struct ramzswap *rzs, int device_id)
 {
        mutex_init(&rzs->lock);
        INIT_LIST_HEAD(&rzs->backing_swap_extent_list);
@@ -1301,7 +1301,7 @@ static void create_device(struct ramzswap *rzs, int device_id)
        if (!rzs->queue) {
                pr_err("Error allocating disk queue for device %d\n",
                        device_id);
-               return;
+               return 0;
        }
 
        blk_queue_make_request(rzs->queue, ramzswap_make_request);
@@ -1313,7 +1313,7 @@ static void create_device(struct ramzswap *rzs, int device_id)
                blk_cleanup_queue(rzs->queue);
                pr_warning("Error allocating disk structure for device %d\n",
                        device_id);
-               return;
+               return 0;
        }
 
        rzs->disk->major = ramzswap_major;
@@ -1331,6 +1331,7 @@ static void create_device(struct ramzswap *rzs, int device_id)
        add_disk(rzs->disk);
 
        rzs->init_done = 0;
+       return 1;
 }
 
 static void destroy_device(struct ramzswap *rzs)
@@ -1368,16 +1369,20 @@ static int __init ramzswap_init(void)
        /* Allocate the device array and initialize each one */
        pr_info("Creating %u devices ...\n", num_devices);
        devices = kzalloc(num_devices * sizeof(struct ramzswap), GFP_KERNEL);
-       if (!devices) {
-               ret = -ENOMEM;
+       if (!devices)
                goto out;
-       }
 
        for (i = 0; i < num_devices; i++)
-               create_device(&devices[i], i);
-
+               if (!create_device(&devices[i], i)) {
+                       ret = i;
+                       goto free_devices;
+               }
        return 0;
+free_devices:
+       for (i = 0; i < ret; i++)
+               destroy_device(&devices[i]);
 out:
+       ret = -ENOMEM;
        unregister_blkdev(ramzswap_major, "ramzswap");
        return ret;
 }