Staging: hv: blkvsc: Fix bugs in the module unload path

Fix bugs in the module unload path for the blkvsc driver.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Abhishek Kane <v-abkane@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/hv/blkvsc_drv.c b/drivers/staging/hv/blkvsc_drv.c
index bcf562f..a44fc76 100644 (file)
--- a/drivers/staging/hv/blkvsc_drv.c
+++ b/drivers/staging/hv/blkvsc_drv.c
@@ -518,22 +518,18 @@ static int blkvsc_remove(struct hv_device *dev)
 
        blkvsc_do_operation(blkdev, DO_FLUSH);
 
-       blk_cleanup_queue(blkdev->gd->queue);
+       if (blkdev->users == 0) {
+               del_gendisk(blkdev->gd);
+               put_disk(blkdev->gd);
+               blk_cleanup_queue(blkdev->gd->queue);
 
-       /*
-        * Call to the vsc driver to let it know that the device is being
-        * removed
-        */
-       storvsc_dev_remove(dev);
-
-       del_gendisk(blkdev->gd);
+               storvsc_dev_remove(blkdev->device_ctx);
 
-       kmem_cache_destroy(blkdev->request_pool);
-
-       kfree(blkdev);
+               kmem_cache_destroy(blkdev->request_pool);
+               kfree(blkdev);
+       }
 
        return 0;
-
 }
 
 static void blkvsc_shutdown(struct hv_device *dev)
@@ -568,13 +564,23 @@ static int blkvsc_release(struct gendisk *disk, fmode_t mode)
        struct block_device_context *blkdev = disk->private_data;
        unsigned long flags;
 
-       if (blkdev->users == 1) {
+       spin_lock_irqsave(&blkdev->lock, flags);
+
+       if ((--blkdev->users == 0) && (blkdev->shutting_down)) {
+               blk_stop_queue(blkdev->gd->queue);
+               spin_unlock_irqrestore(&blkdev->lock, flags);
+
                blkvsc_do_operation(blkdev, DO_FLUSH);
-       }
+               del_gendisk(blkdev->gd);
+               put_disk(blkdev->gd);
+               blk_cleanup_queue(blkdev->gd->queue);
 
-       spin_lock_irqsave(&blkdev->lock, flags);
-       blkdev->users--;
-       spin_unlock_irqrestore(&blkdev->lock, flags);
+               storvsc_dev_remove(blkdev->device_ctx);
+
+               kmem_cache_destroy(blkdev->request_pool);
+               kfree(blkdev);
+       } else
+               spin_unlock_irqrestore(&blkdev->lock, flags);
 
        return 0;
 }