linux-kernel - [RESEND RFC PATCH 00/32] separate operations from flags in the bio/request structs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1446674909-5371-1-git-send-email-mchristi@redhat.com>
Date:	Wed,  4 Nov 2015 16:07:57 -0600
From:	mchristi@...hat.com
To:	linux-fsdevel@...r.kernel.org, dm-devel@...hat.com,
	linux-raid@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-scsi@...r.kernel.org, drbd-dev@...ts.linbit.com
Subject: [RESEND RFC PATCH 00/32] separate operations from flags in the bio/request structs

This is just a resend of the patchset from earlier today. There was
a error in the middle of sending the set, so it looks like 10 - 32 got
dropped.

There are a couple new block layer commands we are trying to add support
for in the near term:

compare and write
http://www.spinics.net/lists/target-devel/msg07826.html

copy offload/extended copy/xcopy
https://www.redhat.com/archives/dm-devel/2014-July/msg00070.html

The problem is if we contine to add more commands we will have to one day
extend the cmd_flags/bi_rw fields again. To prevent that, this patchset
separates the operation (REQ_WRITE, REQ_DISCARD, REQ_WRITE_SAME, etc) from
the flags (REQ_SYNC, REQ_QUIET, etc) in the bio and request structs. In the
end of this set, we will have two fields bio->bi_op/request->op and
bio->bi_rw/request->cmd_flags.

The patches were made against Jens's linux-block tree's for-linus branch:
https://git.kernel.org/cgit/linux/kernel/git/axboe/linux-block.git/log/?h=for-linus
(last commit a22c4d7e34402ccdf3414f64c50365436eba7b93).

I have done some basic testing for a lot of the drivers and filesystems,
but I wanted to get comments before trying to track down more hardware/
systems for testing.

Known issues:
- REQ_FLUSH is still a flag, but should probably be a operation.
 For lower level drivers like SCSI where we only get a flush, it makes
more sense to be a operation. However, upper layers like filesystems
can send down flushes with writes, so it is more of a flag for them.
I am still working on this.

- There is a regression with the dm flakey target. It currently
cannot corrupt the operation values.

- The patchset is a little awkward. It touches so much code,
but I wanted to maintain git bisectibility, so there is lots of compat code
left around until the last patches where everyting is cleaned up.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/