zram: fix unbalanced idr management at hot removal

[firefly-linux-kernel-4.4.55.git] / drivers / block / zram / zram_drv.c

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 81a557c33a1f8b4a41b19f39b58d8c0e0e40ae35..1770c455dfdd3125e639524e0b242027c33a68a8 100644 (file)
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -894,7 +894,7 @@ out:
 /*
  * Handler function for all zram I/O requests.
  */
-static void zram_make_request(struct request_queue *queue, struct bio *bio)
+static blk_qc_t zram_make_request(struct request_queue *queue, struct bio *bio)
 {
        struct zram *zram = queue->queuedata;
 
@@ -911,11 +911,12 @@ static void zram_make_request(struct request_queue *queue, struct bio *bio)
 
        __zram_make_request(zram, bio);
        zram_meta_put(zram);
-       return;
+       return BLK_QC_T_NONE;
 put_zram:
        zram_meta_put(zram);
 error:
        bio_io_error(bio);
+       return BLK_QC_T_NONE;
 }
 
 static void zram_slot_free_notify(struct block_device *bdev,
@@ -1324,7 +1325,6 @@ static int zram_remove(struct zram *zram)
 
        pr_info("Removed device: %s\n", zram->disk->disk_name);
 
-       idr_remove(&zram_index_idr, zram->disk->first_minor);
        blk_cleanup_queue(zram->disk->queue);
        del_gendisk(zram->disk);
        put_disk(zram->disk);
@@ -1366,10 +1366,13 @@ static ssize_t hot_remove_store(struct class *class,
        mutex_lock(&zram_index_mutex);
 
        zram = idr_find(&zram_index_idr, dev_id);
-       if (zram)
+       if (zram) {
                ret = zram_remove(zram);
-       else
+               if (!ret)
+                       idr_remove(&zram_index_idr, dev_id);
+       } else {
                ret = -ENODEV;
+       }
 
        mutex_unlock(&zram_index_mutex);
        return ret ? ret : count;