Re: [PATCH 2/3] fd/locks: allow get the lock owner by F_OFD_GETLK

From: stsp
Date: Wed Jun 21 2023 - 06:45:14 EST



21.06.2023 15:35, Jeff Layton пишет:
I don't think we can change this at this point.

The bottom line (again) is that OFD locks are owned by the file
descriptor (much like with flock()), and since file descriptors can be
shared across multiple process it's impossible to say that some single
process owns it.
What's the problem with 2 owners?
Can't you get one of them, rather than
meaningless -1?
Compare this situation with read locks.
They can overlap, so when you get an
info about a read lock (except for the
new F_UNLCK case), you get the info
about *some* of the locks in that range.
In the case of multiple owners, you
likewise get the info about about some
owner. If you iteratively send them a
"please release this lock" message
(eg in a form of SIGKILL), then you
traverse all, and end up with the
lock-free area.
Is there really any problem here?