From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bart Van Assche Subject: Re: [PATCH 1/2] scsi: add a max_segment_size limitation to struct Scsi_Host Date: Tue, 12 Apr 2016 08:19:20 -0700 Message-ID: <570D11F8.1080707@sandisk.com> References: <1460470405-11673-1-git-send-email-hch@lst.de> <1460470405-11673-2-git-send-email-hch@lst.de> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1460470405-11673-2-git-send-email-hch@lst.de> Sender: linux-scsi-owner@vger.kernel.org To: Christoph Hellwig , linux-rdma@vger.kernel.org, linux-scsi@vger.kernel.org List-Id: linux-rdma@vger.kernel.org On 04/12/2016 07:13 AM, Christoph Hellwig wrote: > diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c > index 8106515..ad79372 100644 > --- a/drivers/scsi/scsi_lib.c > +++ b/drivers/scsi/scsi_lib.c > @@ -2120,7 +2120,8 @@ static void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q) > blk_queue_segment_boundary(q, shost->dma_boundary); > dma_set_seg_boundary(dev, shost->dma_boundary); > > - blk_queue_max_segment_size(q, dma_get_max_seg_size(dev)); > + blk_queue_max_segment_size(q, min_not_zero(shost->max_segment_size, > + dma_get_max_seg_size(dev))); > > if (!shost->use_clustering) > q->limits.cluster = 0; > diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h > index fcfa3d7..f11d3fe 100644 > --- a/include/scsi/scsi_host.h > +++ b/include/scsi/scsi_host.h > @@ -621,6 +621,7 @@ struct Scsi_Host { > short unsigned int sg_tablesize; > short unsigned int sg_prot_tablesize; > unsigned int max_sectors; > + unsigned int max_segment_size; > unsigned long dma_boundary; > /* > * In scsi-mq mode, the number of hardware queues supported by the LLD. Hello Christoph, The value zero has another meaning for Scsi_Host.max_segment_size than for queue_limits.max_segment_size. Shouldn't that be documented somewhere? Thanks, Bart.