Re: [PATCH 2/2] fs/locks: Remove fl_nspid and use fs-specific l_pid for remote locks

From	"Benjamin Coddington" <bcodding@redhat.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH 2/2] fs/locks: Remove fl_nspid and use fs-specific l_pid for remote locks
Date	2017-06-20 21:20 +0200
Message-ID	<tUwQV-4dQ-3@gated-at.bofh.it> (permalink)
References	(1 earlier) <tU4UG-3bd-33@gated-at.bofh.it> <tU8OB-5H3-3@gated-at.bofh.it> <tUs0X-1bG-33@gated-at.bofh.it> <tUu2J-2t3-9@gated-at.bofh.it> <tUuP7-2YK-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

On 20 Jun 2017, at 13:06, Jeff Layton wrote:
>
> Now that I think about it a bit more, I don't think we really need a
> flag here.
>
> Just have the ->lock operation set the fl_pid to a negative value. That
> will never be a valid pid anyway. Then flock_translate_pid could just
> return any negative value directly instead of trying to translate it.
>
> In practice we would always just set it to -1. Maybe even add something
> like this that the lock-> operation could set it to?
>
> #define    FILE_LOCK_OWNER_UNDEFINED       -1

So for filesystems that set a remote pid, they should negate the pid to mean
that the pid should not be translated?  Then when we return that pid, we
flip it back again, or display a negative number, or turn it into -1?

The flag, having a readable name, would make things a bit clearer as to what
the filesystems expect to happen to that pid value.

Ben

Thread

Re: [PATCH 2/2] fs/locks: Remove fl_nspid and use fs-specific l_pid  for remote locks "Benjamin Coddington" <bcodding@redhat.com> - 2017-06-20 16:10 +0200
  Re: [PATCH 2/2] fs/locks: Remove fl_nspid and use fs-specific l_pid  for remote locks "Benjamin Coddington" <bcodding@redhat.com> - 2017-06-20 18:20 +0200
    Re: [PATCH 2/2] fs/locks: Remove fl_nspid and use fs-specific l_pid  for remote locks Jeff Layton <jlayton@poochiereds.net> - 2017-06-20 19:10 +0200
      Re: [PATCH 2/2] fs/locks: Remove fl_nspid and use fs-specific l_pid  for remote locks "Benjamin Coddington" <bcodding@redhat.com> - 2017-06-20 21:20 +0200
        Re: [PATCH 2/2] fs/locks: Remove fl_nspid and use fs-specific l_pid  for remote locks Jeff Layton <jlayton@poochiereds.net> - 2017-06-20 21:40 +0200
          Re: [PATCH 2/2] fs/locks: Remove fl_nspid and use fs-specific l_pid  for remote locks "Benjamin Coddington" <bcodding@redhat.com> - 2017-06-20 21:50 +0200
            Re: [PATCH 2/2] fs/locks: Remove fl_nspid and use fs-specific l_pid  for remote locks Jeff Layton <jlayton@poochiereds.net> - 2017-06-20 22:20 +0200

csiph-web