[PATCH] nvmet: check that host sqsize does not exceed ctrl MQES

[Sagi Grimberg]

> From: Amit Engel <amit.engel at dell.com>
> 
> Check that host sqsize is not greater-than
> Maximum Queue Entries Supported (MQES) by the ctrl
> 
> Signed-off-by: Amit Engel <amit.engel at dell.com>
> ---
>   drivers/nvme/target/fabrics-cmd.c | 9 +++++++++
>   1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/nvme/target/fabrics-cmd.c b/drivers/nvme/target/fabrics-cmd.c
> index 7d0f3523fdab..2b4a41b45c45 100644
> --- a/drivers/nvme/target/fabrics-cmd.c
> +++ b/drivers/nvme/target/fabrics-cmd.c
> @@ -109,6 +109,7 @@ static u16 nvmet_install_queue(struct nvmet_ctrl *ctrl, struct nvmet_req *req)
>   	u16 qid = le16_to_cpu(c->qid);
>   	u16 sqsize = le16_to_cpu(c->sqsize);
>   	struct nvmet_ctrl *old;
> +	u16 mqes = NVME_CAP_MQES(ctrl->cap);
>   	u16 ret;
>   
>   	old = cmpxchg(&req->sq->ctrl, NULL, ctrl);
> @@ -123,6 +124,14 @@ static u16 nvmet_install_queue(struct nvmet_ctrl *ctrl, struct nvmet_req *req)
>   		ret = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
>   		goto err;
>   	}
> +	/* sqsize is not allowed to exceed Maximum Queue Entries Supported (MQES) */

Little redundant comment I think (it is also printed in the error).

> +	if (sqsize > mqes) {
> +		pr_warn("sqsize %u is larger than MQES supported %u cntlid %d\n",
> +				sqsize, mqes, ctrl->cntlid);
> +		req->error_loc = offsetof(struct nvmf_connect_command, sqsize);
> +		req->cqe->result.u32 = IPO_IATTR_CONNECT_SQE(sqsize);
> +		return NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
> +	}

Otherwise,
Reviewed-by: Sagi Grimberg <sagi at grimberg.me>