1 files changed, 29 insertions, 17 deletions

diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c
index ec66b0a5873b..6fb2be31b3f8 100644
--- a/drivers/staging/zram/zram_drv.c
+++ b/drivers/staging/zram/zram_drv.c
@@ -560,27 +560,34 @@ static int zram_make_request(struct request_queue *queue, struct bio *bio)
 {
 	struct zram *zram = queue->queuedata;
 
+	if (unlikely(!zram->init_done) && zram_init_device(zram))
+		goto error;
+
+	down_read(&zram->init_lock);
+	if (unlikely(!zram->init_done))
+		goto error_unlock;
+
 	if (!valid_io_request(zram, bio)) {
 		zram_stat64_inc(zram, &zram->stats.invalid_io);
-		bio_io_error(bio);
-		return 0;
-	}
-
-	if (unlikely(!zram->init_done) && zram_init_device(zram)) {
-		bio_io_error(bio);
-		return 0;
+		goto error_unlock;
 	}
 
 	__zram_make_request(zram, bio, bio_data_dir(bio));
+	up_read(&zram->init_lock);
 
 	return 0;
+
+error_unlock:
+	up_read(&zram->init_lock);
+error:
+	bio_io_error(bio);
+	return 0;
 }
 
-void zram_reset_device(struct zram *zram)
+void __zram_reset_device(struct zram *zram)
 {
 	size_t index;
 
-	mutex_lock(&zram->init_lock);
 	zram->init_done = 0;
 
 	/* Free various per-device buffers */
@@ -617,7 +624,13 @@ void zram_reset_device(struct zram *zram)
 	memset(&zram->stats, 0, sizeof(zram->stats));
 
 	zram->disksize = 0;
-	mutex_unlock(&zram->init_lock);
+}
+
+void zram_reset_device(struct zram *zram)
+{
+	down_write(&zram->init_lock);
+	__zram_reset_device(zram);
+	up_write(&zram->init_lock);
 }
 
 int zram_init_device(struct zram *zram)
@@ -625,10 +638,10 @@ int zram_init_device(struct zram *zram)
 	int ret;
 	size_t num_pages;
 
-	mutex_lock(&zram->init_lock);
+	down_write(&zram->init_lock);
 
 	if (zram->init_done) {
-		mutex_unlock(&zram->init_lock);
+		up_write(&zram->init_lock);
 		return 0;
 	}
 
@@ -671,15 +684,14 @@ int zram_init_device(struct zram *zram)
 	}
 
 	zram->init_done = 1;
-	mutex_unlock(&zram->init_lock);
+	up_write(&zram->init_lock);
 
 	pr_debug("Initialization done!\n");
 	return 0;
 
 fail:
-	mutex_unlock(&zram->init_lock);
-	zram_reset_device(zram);
-
+	__zram_reset_device(zram);
+	up_write(&zram->init_lock);
 	pr_err("Initialization failed: err=%d\n", ret);
 	return ret;
 }
@@ -703,7 +715,7 @@ static int create_device(struct zram *zram, int device_id)
 	int ret = 0;
 
 	init_rwsem(&zram->lock);
-	mutex_init(&zram->init_lock);
+	init_rwsem(&zram->init_lock);
 	spin_lock_init(&zram->stat64_lock);
 
 	zram->queue = blk_alloc_queue(GFP_KERNEL);