Re: [PATCH 3/5] block: move bdev_mark_dead out of disk_check_media_change

[Jan Kara <jack@suse.cz>]

On Tue 17-10-23 20:48:21, Christoph Hellwig wrote:
> disk_check_media_change is mostly called from ->open where it makes
> little sense to mark the file system on the device as dead, as we
> are just opening it.  So instead of calling bdev_mark_dead from
> disk_check_media_change move it into the few callers that are not
> in an open instance.  This avoid calling into bdev_mark_dead and
> thus taking s_umount with open_mutex held.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Nice and looks good to me (with the fixed up export). Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza


> ---
>  block/disk-events.c     | 18 +++++++-----------
>  drivers/block/ataflop.c |  4 +++-
>  drivers/block/floppy.c  |  4 +++-
>  3 files changed, 13 insertions(+), 13 deletions(-)
> 
> diff --git a/block/disk-events.c b/block/disk-events.c
> index 13c3372c465a39..2f697224386aa8 100644
> --- a/block/disk-events.c
> +++ b/block/disk-events.c
> @@ -266,11 +266,8 @@ static unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask)
>   * disk_check_media_change - check if a removable media has been changed
>   * @disk: gendisk to check
>   *
> - * Check whether a removable media has been changed, and attempt to free all
> - * dentries and inodes and invalidates all block device page cache entries in
> - * that case.
> - *
> - * Returns %true if the media has changed, or %false if not.
> + * Returns %true and marks the disk for a partition rescan whether a removable
> + * media has been changed, and %false if the media did not change.
>   */
>  bool disk_check_media_change(struct gendisk *disk)
>  {
> @@ -278,12 +275,11 @@ bool disk_check_media_change(struct gendisk *disk)
>  
>  	events = disk_clear_events(disk, DISK_EVENT_MEDIA_CHANGE |
>  				   DISK_EVENT_EJECT_REQUEST);
> -	if (!(events & DISK_EVENT_MEDIA_CHANGE))
> -		return false;
> -
> -	bdev_mark_dead(disk->part0, true);
> -	set_bit(GD_NEED_PART_SCAN, &disk->state);
> -	return true;
> +	if (events & DISK_EVENT_MEDIA_CHANGE) {
> +		set_bit(GD_NEED_PART_SCAN, &disk->state);
> +		return true;
> +	}
> +	return false;
>  }
>  EXPORT_SYMBOL(disk_check_media_change);
>  
> diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
> index cd738cab725f39..50949207798d2a 100644
> --- a/drivers/block/ataflop.c
> +++ b/drivers/block/ataflop.c
> @@ -1760,8 +1760,10 @@ static int fd_locked_ioctl(struct block_device *bdev, blk_mode_t mode,
>  		/* invalidate the buffer track to force a reread */
>  		BufferDrive = -1;
>  		set_bit(drive, &fake_change);
> -		if (disk_check_media_change(disk))
> +		if (disk_check_media_change(disk)) {
> +			bdev_mark_dead(disk->part0, true);
>  			floppy_revalidate(disk);
> +		}
>  		return 0;
>  	default:
>  		return -EINVAL;
> diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
> index ea4eb88a2e45f4..11114a5d9e5c46 100644
> --- a/drivers/block/floppy.c
> +++ b/drivers/block/floppy.c
> @@ -3215,8 +3215,10 @@ static int invalidate_drive(struct gendisk *disk)
>  	/* invalidate the buffer track to force a reread */
>  	set_bit((long)disk->private_data, &fake_change);
>  	process_fd_request();
> -	if (disk_check_media_change(disk))
> +	if (disk_check_media_change(disk)) {
> +		bdev_mark_dead(disk->part0, true);
>  		floppy_revalidate(disk);
> +	}
>  	return 0;
>  }
>  
> -- 
> 2.39.2
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR