Re: [PATCH v3 0/3] nvme_map_user_request() cleanup

[Chaitanya Kulkarni <chaitanyak@nvidia.com>]

On 3/24/25 13:05, Caleb Sander Mateos wrote:
> The first commit removes a WARN_ON_ONCE() checking userspace values.
> The last 2 move code out of nvme_map_user_request() that belongs better
> in its callers, and move the fixed buffer import before going async.
> As discussed in [1], this allows an NVMe passthru operation submitted at
> the same time as a ublk zero-copy buffer unregister operation to succeed
> even if the initial issue goes async. This can improve performance of
> userspace applications submitting the operations together like this with
> a slow fallback path on failure. This is an alternate approach to [2],
> which moved the fixed buffer import to the io_uring layer.
>
> There will likely be conflicts with the parameter cleanup series Keith
> posted last month in [3].
>
> The series is based on block/for-6.15/io_uring, with commit 00817f0f1c45
> ("nvme-ioctl: fix leaked requests on mapping error") cherry-picked.
>
> [1]:https://lore.kernel.org/io-uring/20250321184819.3847386-1-csander@purestorage.com/T/#u
> [2]:https://lore.kernel.org/io-uring/20250321184819.3847386-4-csander@purestorage.com/
> [3]:https://lore.kernel.org/all/20250224182128.2042061-1-kbusch@meta.com/T/#u
>
> v3: Move the fixed buffer import before allocating a blk-mq request
>
> v2: Fix iov_iter value passed to nvme_map_user_request()

Looks good to me.

Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

-ck