Re: [GIT PULL] Final io_uring updates for 6.4-rc1

[Chen-Yu Tsai]

Hi,

On Sun, May 07, 2023 at 06:00:48AM -0600, Jens Axboe wrote:
> Hi Linus,
> 
> Nothing major in here, just two different parts:
> 
> - Small series from Breno that enables passing the full SQE down
>   for ->uring_cmd(). This is a prerequisite for enabling full network
>   socket operations. Queued up a bit late because of some stylistic
>   concerns that got resolved, would be nice to have this in 6.4-rc1
>   so the dependent work will be easier to handle for 6.5.
> 
> - Fix for the huge page coalescing, which was a regression introduced
>   in the 6.3 kernel release (Tobias).
> 
> Note that this will throw a merge conflict in the ublk_drv code, due
> to this branch still being based off the original for-6.4/io_uring
> branch. Resolution is pretty straight forward, I'm including it below
> for reference.
> 
> Please pull!
> 
> 
> The following changes since commit 3c85cc43c8e7855d202da184baf00c7b8eeacf71:
> 
>   Revert "io_uring/rsrc: disallow multi-source reg buffers" (2023-04-20 06:51:48 -0600)
> 
> are available in the Git repository at:
> 
>   git://git.kernel.dk/linux.git tags/for-6.4/io_uring-2023-05-07
> 
> for you to fetch changes up to d2b7fa6174bc4260e496cbf84375c73636914641:
> 
>   io_uring: Remove unnecessary BUILD_BUG_ON (2023-05-04 08:19:05 -0600)
> 
> ----------------------------------------------------------------
> for-6.4/io_uring-2023-05-07
> 
> ----------------------------------------------------------------
> Breno Leitao (3):
>       io_uring: Create a helper to return the SQE size
>       io_uring: Pass whole sqe to commands

This commit causes broken builds when IO_URING=n and NVME_CORE=y, as
io_uring_sqe_cmd(), called in drivers/nvme/host/ioctl.c, ends up being
undefined. This was also reported [1] by 0-day bot on your branch
yesterday, but it's worse now that Linus merged the pull request.

Not sure what the better fix would be. Move io_uring_sqe_cmd() outside
of the "#if defined(CONFIG_IO_URING)" block?


ChenYu

[1] https://lore.kernel.org/all/202305080039.r7cguaXB-lkp@xxxxxxxxx/

>       io_uring: Remove unnecessary BUILD_BUG_ON
> 
> Tobias Holl (1):
>       io_uring/rsrc: check for nonconsecutive pages
> 
>  drivers/block/ublk_drv.c  | 26 +++++++++++++-------------
>  drivers/nvme/host/ioctl.c |  2 +-
>  include/linux/io_uring.h  |  7 ++++++-
>  io_uring/io_uring.h       | 10 ++++++++++
>  io_uring/opdef.c          |  2 +-
>  io_uring/rsrc.c           |  7 ++++++-
>  io_uring/uring_cmd.c      | 12 +++---------
>  io_uring/uring_cmd.h      |  8 --------
>  8 files changed, 40 insertions(+), 34 deletions(-)
> 
> Merge resolution:
> 
> commit 775e045e380626ce769d95badc79ea08edc1b15d
> Merge: efd141da30bb d2b7fa6174bc
> Author: Jens Axboe <axboe@xxxxxxxxx>
> Date:   Thu May 4 08:22:24 2023 -0600
> 
>     Merge branch 'for-6.4/io_uring' into test
>     
>     * for-6.4/io_uring:
>       io_uring: Remove unnecessary BUILD_BUG_ON
>       io_uring: Pass whole sqe to commands
>       io_uring: Create a helper to return the SQE size
>       io_uring/rsrc: check for nonconsecutive pages
>     
>     Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
> 
> diff --cc drivers/block/ublk_drv.c
> index 72a5cde9a5af,42f4d7ca962e..0af6a41f92b2
> --- a/drivers/block/ublk_drv.c
> +++ b/drivers/block/ublk_drv.c
> @@@ -1397,23 -1362,6 +1397,23 @@@ static int __ublk_ch_uring_cmd(struct i
>   	return -EIOCBQUEUED;
>   }
>   
>  +static int ublk_ch_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
>  +{
> - 	struct ublksrv_io_cmd *ub_src = (struct ublksrv_io_cmd *) cmd->cmd;
> ++	const struct ublksrv_io_cmd *ub_src = io_uring_sqe_cmd(cmd->sqe);
>  +	struct ublksrv_io_cmd ub_cmd;
>  +
>  +	/*
>  +	 * Not necessary for async retry, but let's keep it simple and always
>  +	 * copy the values to avoid any potential reuse.
>  +	 */
>  +	ub_cmd.q_id = READ_ONCE(ub_src->q_id);
>  +	ub_cmd.tag = READ_ONCE(ub_src->tag);
>  +	ub_cmd.result = READ_ONCE(ub_src->result);
>  +	ub_cmd.addr = READ_ONCE(ub_src->addr);
>  +
>  +	return __ublk_ch_uring_cmd(cmd, issue_flags, &ub_cmd);
>  +}
>  +
>   static const struct file_operations ublk_ch_fops = {
>   	.owner = THIS_MODULE,
>   	.open = ublk_ch_open,
> @@@ -2240,9 -2171,8 +2240,9 @@@ exit
>   static int ublk_ctrl_uring_cmd(struct io_uring_cmd *cmd,
>   		unsigned int issue_flags)
>   {
> - 	struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd;
> + 	const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe);
>   	struct ublk_device *ub = NULL;
>  +	u32 cmd_op = cmd->cmd_op;
>   	int ret = -EINVAL;
>   
>   	if (issue_flags & IO_URING_F_NONBLOCK)
> 
> -- 
> Jens Axboe
> 
>