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* [RFC PATCH 00/32] separate operations from flags in the bio/request structs
@ 2015-11-04 16:32 mchristi
  2015-11-04 16:32 ` [PATCH 01/32] block/fs: add REQ_OP definitions mchristi
                   ` (9 more replies)
  0 siblings, 10 replies; 17+ messages in thread
From: mchristi @ 2015-11-04 16:32 UTC (permalink / raw)
  To: linux-fsdevel, dm-devel, linux-raid, linux-kernel, linux-scsi, drbd-dev

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.



^ permalink raw reply	[flat|nested] 17+ messages in thread
* [RESEND RFC PATCH 00/32] separate operations from flags in the bio/request structs
@ 2015-11-04 22:07 mchristi
  2015-11-04 22:08 ` [PATCH 06/32] xen blkback: prepare for bi_rw split mchristi
  0 siblings, 1 reply; 17+ messages in thread
From: mchristi @ 2015-11-04 22:07 UTC (permalink / raw)
  To: linux-fsdevel, dm-devel, linux-raid, linux-kernel, linux-scsi, drbd-dev

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.




^ permalink raw reply	[flat|nested] 17+ messages in thread

end of thread, other threads:[~2015-11-11 17:37 UTC | newest]

Thread overview: 17+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-11-04 16:32 [RFC PATCH 00/32] separate operations from flags in the bio/request structs mchristi
2015-11-04 16:32 ` [PATCH 01/32] block/fs: add REQ_OP definitions mchristi
2015-11-04 16:32 ` [PATCH 02/32] block/fs/mm: prepare submit_bio_wait users for bi_rw split mchristi
2015-11-04 16:32 ` [PATCH 03/32] dio/btrfs: prep dio->submit_bio " mchristi
2015-11-04 16:32 ` [PATCH 04/32] block: prepare blkdev_issue_discard " mchristi
2015-11-04 16:33 ` [PATCH 05/32] drbd: prepare drbd " mchristi
2015-11-04 16:33 ` [PATCH 06/32] xen blkback: prepare " mchristi
2015-11-04 16:33 ` [PATCH 07/32] dm: " mchristi
2015-11-04 16:33 ` [PATCH 08/32] target: " mchristi
2015-11-04 16:33 ` [PATCH 09/32] btrfs: " mchristi
2015-11-04 16:49 ` [dm-devel] [RFC PATCH 00/32] separate operations from flags in the bio/request structs Bart Van Assche
2015-11-04 16:53   ` Mike Christie
2015-11-07 10:23     ` Christoph Hellwig
2015-11-11  7:53       ` Mike Christie
2015-11-11 11:28         ` Christoph Hellwig
2015-11-11 17:37           ` Mike Snitzer
2015-11-04 22:07 [RESEND RFC " mchristi
2015-11-04 22:08 ` [PATCH 06/32] xen blkback: prepare for bi_rw split mchristi

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