Commit 44c3c625 authored by Max Gurtovoy's avatar Max Gurtovoy Committed by Christoph Hellwig
Browse files

nvme-rdma: limit the maximal queue size for RDMA controllers 



Corrent limit of 1024 isn't valid for some of the RDMA based ctrls. In
case the target expose a cap of larger amount of entries (e.g. 1024),
the initiator may fail to create a QP with this size. Thus limit to a
value that works for all RDMA adapters.

Future general solution should use RDMA/core API to calculate this size
according to device capabilities and number of WRs needed per NVMe IO
request.

Signed-off-by: default avatarMax Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent 2351ead9

drivers/nvme/host/rdma.c

+7 −0
Original line number Diff line number Diff line
@@ -1112,6 +1112,13 @@ static int nvme_rdma_setup_ctrl(struct nvme_rdma_ctrl *ctrl, bool new) 
			ctrl->ctrl.opts->queue_size, ctrl->ctrl.sqsize + 1);

	}



	if (ctrl->ctrl.sqsize + 1 > NVME_RDMA_MAX_QUEUE_SIZE) {

		dev_warn(ctrl->ctrl.device,

			"ctrl sqsize %u > max queue size %u, clamping down\n",

			ctrl->ctrl.sqsize + 1, NVME_RDMA_MAX_QUEUE_SIZE);

		ctrl->ctrl.sqsize = NVME_RDMA_MAX_QUEUE_SIZE - 1;

	}



	if (ctrl->ctrl.sqsize + 1 > ctrl->ctrl.maxcmd) {

		dev_warn(ctrl->ctrl.device,

			"sqsize %u > ctrl maxcmd %u, clamping down\n",

include/linux/nvme-rdma.h

+2 −0
Original line number Diff line number Diff line
@@ -6,6 +6,8 @@ 
#ifndef _LINUX_NVME_RDMA_H

#define _LINUX_NVME_RDMA_H



#define NVME_RDMA_MAX_QUEUE_SIZE	128



enum nvme_rdma_cm_fmt {

	NVME_RDMA_CM_FMT_1_0 = 0x0,

};