[dm-devel] [PATCH] block: make discard killable

[Jens Axboe]

On 7/3/18 11:35 AM, Mikulas Patocka wrote:
> Discarding can take very long time for some device mapper targets, this
> patch makes it possible to kill a process that issues the BLKDISCARD
> ioctl.
> 
> Note that some filesystems call blkdev_issue_discard or
> __blkdev_issue_discard directly, they may not be prepared to handle the
> failure, so this patch introduces a flag BLKDEV_DISCARD_KILLABLE that is
> only set when the discard is initiated by an ioctl.

This might be cleaner as a regular request flag, since killable can
apply to other types of IO as well - like readahead.

-- 
Jens Axboe