Re: [PATCH 2/2] bdev: Refresh bdev size for disks without partitioning

[Guoqing Jiang <guoqing.jiang@cloud.ionos.com>]

On 10/21/19 10:38 AM, Jan Kara wrote:
> Currently, block device size in not updated on second and further open
> for block devices where partition scan is disabled. This is particularly
> annoying for example for DVD drives as that means block device size does
> not get updated once the media is inserted into a drive if the device is
> already open when inserting the media. This is actually always the case
> for example when pktcdvd is in use.
>
> Fix the problem by revalidating block device size on every open even for
> devices with partition scan disabled.
>
> Signed-off-by: Jan Kara <jack@suse.cz>
> ---
>   fs/block_dev.c | 19 ++++++++++---------
>   1 file changed, 10 insertions(+), 9 deletions(-)
>
> diff --git a/fs/block_dev.c b/fs/block_dev.c
> index 88c6d35ec71d..d612468ee66b 100644
> --- a/fs/block_dev.c
> +++ b/fs/block_dev.c
> @@ -1403,11 +1403,7 @@ static void flush_disk(struct block_device *bdev, bool kill_dirty)
>   		       "resized disk %s\n",
>   		       bdev->bd_disk ? bdev->bd_disk->disk_name : "");
>   	}
> -
> -	if (!bdev->bd_disk)
> -		return;
> -	if (disk_part_scan_enabled(bdev->bd_disk))
> -		bdev->bd_invalidated = 1;
> +	bdev->bd_invalidated = 1;
>   }
>   
>   /**
> @@ -1514,10 +1510,15 @@ static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part);
>   
>   static void bdev_disk_changed(struct block_device *bdev, bool invalidate)
>   {
> -	if (invalidate)
> -		invalidate_partitions(bdev->bd_disk, bdev);
> -	else
> -		rescan_partitions(bdev->bd_disk, bdev);
> +	if (disk_part_scan_enabled(bdev->bd_disk)) {
> +		if (invalidate)
> +			invalidate_partitions(bdev->bd_disk, bdev);
> +		else
> +			rescan_partitions(bdev->bd_disk, bdev);

Maybe use the new common helper to replace above.

Thanks,
Guoqing

> +	} else {
> +		check_disk_size_change(bdev->bd_disk, bdev, !invalidate);
> +		bdev->bd_invalidated = 0;
> +	}
>   }
>   
>   /*