[PATCH 2/4] nvme: split command copy into a helper

[Max Gurtovoy]

On 12/15/2021 6:24 PM, Jens Axboe wrote:
> We'll need it for batched submit as well.
>
> Reviewed-by: Chaitanya Kulkarni <kch at nvidia.com>
> Reviewed-by: Hannes Reinecke <hare at suse.de>
> Signed-off-by: Jens Axboe <axboe at kernel.dk>
> ---
>   drivers/nvme/host/pci.c | 14 ++++++++++----
>   1 file changed, 10 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index 8637538f3fd5..09ea21f75439 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -500,6 +500,15 @@ static inline void nvme_write_sq_db(struct nvme_queue *nvmeq, bool write_sq)
>   	nvmeq->last_sq_tail = nvmeq->sq_tail;
>   }
>   
> +static inline void nvme_sq_copy_cmd(struct nvme_queue *nvmeq,
> +				    struct nvme_command *cmd)
> +{
> +	memcpy(nvmeq->sq_cmds + (nvmeq->sq_tail << nvmeq->sqes), cmd,
> +		sizeof(*cmd));
> +	if (++nvmeq->sq_tail == nvmeq->q_depth)
> +		nvmeq->sq_tail = 0;
> +}
> +
>   /**
>    * nvme_submit_cmd() - Copy a command into a queue and ring the doorbell
>    * @nvmeq: The queue to use
> @@ -510,10 +519,7 @@ static void nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd,
>   			    bool write_sq)
>   {
>   	spin_lock(&nvmeq->sq_lock);
> -	memcpy(nvmeq->sq_cmds + (nvmeq->sq_tail << nvmeq->sqes),
> -	       cmd, sizeof(*cmd));
> -	if (++nvmeq->sq_tail == nvmeq->q_depth)
> -		nvmeq->sq_tail = 0;
> +	nvme_sq_copy_cmd(nvmeq, cmd);
>   	nvme_write_sq_db(nvmeq, write_sq);
>   	spin_unlock(&nvmeq->sq_lock);
>   }

Looks good,

Reviewed-by: Max Gurtovoy <mgurtovoy at nvidia.com>