Re: [PATCH] block: Make blkdev_issue_discard() interruptible

Mike Snitzer
2010-09-15T14:59:48Z

On Wed, Sep 15, 2010 at 10:32 AM, Lukas Czerner <lczerner@redhat.com> wrote:
> Since the discard may take quite long time, especially with really big
> extents (like the whole device for example), it would be nice to give to
> users the opportunity to abort it. This is especially useful for mkfs,
> when user can not know in advance how long it will take.
>
> In conjunction with mke2fs patch "Inform user about ongoing discard"
> it gives the user all the comfort of being informed about discard and
> being able to abort the operation.
>
> Signed-off-by: Lukas Czerner <lczerner@redhat.com>
> ---
>  block/blk-lib.c |    5 +++++
>  1 files changed, 5 insertions(+), 0 deletions(-)
>
> diff --git a/block/blk-lib.c b/block/blk-lib.c
> index d0216b9..4f54a1a 100644
> --- a/block/blk-lib.c
> +++ b/block/blk-lib.c
> @@ -102,6 +102,11 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
>                else if (!bio_flagged(bio, BIO_UPTODATE))
>                        ret = -EIO;
>                bio_put(bio);
> +
> +               if (signal_pending(current)) {
> +                       ret = -ERESTARTSYS;
> +                       break;
> +               }
>        }
>        return ret;
>  out_free_page:

Neil Brown recently suggested the use of fatal_signal_pending() rather
than signal_epnding() in another thread:
http://lkml.org/lkml/2010/9/12/232

I think Neil's suggestion applies here too?

Mike