[PATCH 4/5] nvme: split out metadata vs non metadata end_io uring_cmd completions

[Christoph Hellwig]

> +	union {
> +		struct {
> +			void *meta; /* kernel-resident buffer */
> +			void __user *meta_buffer;
> +		};
> +		struct {
> +			u32 nvme_flags;
> +			u32 nvme_status;
> +			u64 result;
> +		};
> +	};

Without naming the arms of the union this is becoming a bit too much
of a mess..

> +static void nvme_uring_task_cb(struct io_uring_cmd *ioucmd)
> +{
> +	struct nvme_uring_cmd_pdu *pdu = nvme_uring_cmd_pdu(ioucmd);
> +	int status;
> +
> +	if (pdu->nvme_flags & NVME_REQ_CANCELLED)
> +		status = -EINTR;
> +	else
> +		status = pdu->nvme_status;

If you add a signed int field you only need one field instead of
two in the pdu for this (the nvme status is only 15 bits anyway).