[RFC,0/32] block: Make blkdev_get_by_*() return handle

Message

Jan Kara July 4, 2023, 12:21 p.m. UTC

Hello,

this patch series implements the idea of blkdev_get_by_*() calls returning
bdev_handle which is then passed to blkdev_put() [1]. This makes the get
and put calls for bdevs more obviously matching and allows us to propagate
context from get to put without having to modify all the users (again!).
In particular I need to propagate used open flags to blkdev_put() to be able
count writeable opens and add support for blocking writes to mounted block
devices. I'll send that series separately.

The series is based on Linus' tree as of yesterday + two bcache fixes which are
in the block tree. Patches have passed some basic testing, I plan to test more
users once we agree this is the right way to go.

								Honza

[1] https://lore.kernel.org/all/[e-mail]

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Comments

Christoph Hellwig July 6, 2023, 2:54 p.m. UTC | #1

On Tue, Jul 04, 2023 at 02:21:27PM +0200, Jan Kara wrote:
> Hello,
> 
> this patch series implements the idea of blkdev_get_by_*() calls returning
> bdev_handle which is then passed to blkdev_put() [1]. This makes the get
> and put calls for bdevs more obviously matching and allows us to propagate
> context from get to put without having to modify all the users (again!).
> In particular I need to propagate used open flags to blkdev_put() to be able
> count writeable opens and add support for blocking writes to mounted block
> devices. I'll send that series separately.
> 
> The series is based on Linus' tree as of yesterday + two bcache fixes which are
> in the block tree. Patches have passed some basic testing, I plan to test more
> users once we agree this is the right way to go.

Can you post a link to a git branch for this and the follow up series?
Especially with a fairly unstable base it's kinda hard to look at the
result otherwise.