> > We've changed the discard command handling into parallel manner.
> > But, in this change, I forgot decreasing the usage count of the bio
> > which was used to send discard request. I'm sorry about that.
> >
> > Signed-off-by: Daeho Jeong <daeho.jeong@xxxxxxxxxxx>
> > Fixes: a015434480dc ("ext4: send parallel discards on commit
> > completions")
> Why do you think this is needed? submit_bio_wait() consumes the reference
> that you've got from __blkdev_issue_discard()...
>
> Honza
Hi Jan,
I thought like you, but submit_bio_wait() doesn't consume the reference
of the bio and the bio cannot be released after the I/O has been completed.
The caller of submit_bio_wait() should invoke bio_put() in person.
You can see what we have to do after calling submit_bio_wait() in
fs/crypto/bio.c.
Actually, in our device, I can see that the slab memory grows gradually
because of the unreleased discard bios.
