From mboxrd@z Thu Jan 1 00:00:00 1970 From: kys@exchange.microsoft.com Subject: [PATCH 4/6] storvsc: use tagged SRB requests if supported by the device Date: Wed, 14 Dec 2016 18:46:01 -0800 Message-ID: <1481769963-2069-4-git-send-email-kys@exchange.microsoft.com> References: <1481769928-2026-1-git-send-email-kys@exchange.microsoft.com> <1481769963-2069-1-git-send-email-kys@exchange.microsoft.com> Reply-To: kys@microsoft.com Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1481769963-2069-1-git-send-email-kys@exchange.microsoft.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: driverdev-devel-bounces@linuxdriverproject.org Sender: "devel" To: linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, ohering@suse.com, linux-scsi@vger.kernel.org, apw@canonical.com, vkuznets@redhat.com, jasowang@redhat.com, martin.petersen@oracle.com, hare@suse.de, James.Bottomley@HansenPartnership.com Cc: stable@vger.kernel.org List-Id: linux-scsi@vger.kernel.org From: Long Li Properly set SRB flags when hosting device supports tagged queuing. This patch improves the performance on Fiber Channel disks. Signed-off-by: Long Li Reviewed-by: K. Y. Srinivasan Signed-off-by: K. Y. Srinivasan Cc: --- drivers/scsi/storvsc_drv.c | 9 +++++++++ 1 files changed, 9 insertions(+), 0 deletions(-) diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index 63f6b1a..3209387 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -136,6 +136,8 @@ struct hv_fc_wwn_packet { #define SRB_FLAGS_PORT_DRIVER_RESERVED 0x0F000000 #define SRB_FLAGS_CLASS_DRIVER_RESERVED 0xF0000000 +#define SP_UNTAGGED ((unsigned char) ~0) +#define SRB_SIMPLE_TAG_REQUEST 0x20 /* * Platform neutral description of a scsi request - @@ -1549,6 +1551,13 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd) vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DISABLE_SYNCH_TRANSFER; + if (scmnd->device->tagged_supported) { + vm_srb->win8_extension.srb_flags |= + (SRB_FLAGS_QUEUE_ACTION_ENABLE | SRB_FLAGS_NO_QUEUE_FREEZE); + vm_srb->win8_extension.queue_tag = SP_UNTAGGED; + vm_srb->win8_extension.queue_action = SRB_SIMPLE_TAG_REQUEST; + } + /* Build the SRB */ switch (scmnd->sc_data_direction) { case DMA_TO_DEVICE: -- 1.7.4.1