Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932084Ab1F2O1F (ORCPT ); Wed, 29 Jun 2011 10:27:05 -0400 Received: from p3plsmtps2ded02.prod.phx3.secureserver.net ([208.109.80.59]:51167 "HELO p3plsmtps2ded02-01.prod.phx3.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755981Ab1F2OWz (ORCPT ); Wed, 29 Jun 2011 10:22:55 -0400 From: "K. Y. Srinivasan" To: gregkh@suse.de, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, virtualization@lists.osdl.org Cc: "K. Y. Srinivasan" , Haiyang Zhang , Abhishek Kane , Hank Janssen Subject: [PATCH 29/40] Staging: hv: storvsc: Optimize bounce buffer handling for the "write" case Date: Wed, 29 Jun 2011 07:39:26 -0700 Message-Id: <1309358377-8537-29-git-send-email-kys@microsoft.com> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1309358377-8537-1-git-send-email-kys@microsoft.com> References: <1309358301-8488-1-git-send-email-kys@microsoft.com> <1309358377-8537-1-git-send-email-kys@microsoft.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1714 Lines: 47 Optimize bounce buffer handling for the "write" case; we need to copy from bounce buffer only when we are performing a "read" operation. Signed-off-by: K. Y. Srinivasan Signed-off-by: Haiyang Zhang Signed-off-by: Abhishek Kane Signed-off-by: Hank Janssen --- drivers/staging/hv/storvsc_drv.c | 11 ++++++----- 1 files changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c index fc53bf6..c6838fd 100644 --- a/drivers/staging/hv/storvsc_drv.c +++ b/drivers/staging/hv/storvsc_drv.c @@ -478,17 +478,18 @@ static void storvsc_commmand_completion(struct hv_storvsc_request *request) struct scsi_sense_hdr sense_hdr; struct vmscsi_request *vm_srb; + vm_srb = &request->vstor_packet.vm_srb; if (cmd_request->bounce_sgl_count) { - /* FIXME: We can optimize on writes by just skipping this */ - copy_from_bounce_buffer(scsi_sglist(scmnd), + if (vm_srb->data_in == READ_TYPE) { + copy_from_bounce_buffer(scsi_sglist(scmnd), cmd_request->bounce_sgl, scsi_sg_count(scmnd)); - destroy_bounce_buffer(cmd_request->bounce_sgl, - cmd_request->bounce_sgl_count); + destroy_bounce_buffer(cmd_request->bounce_sgl, + cmd_request->bounce_sgl_count); + } } - vm_srb = &request->vstor_packet.vm_srb; scmnd->result = vm_srb->scsi_status; if (scmnd->result) { -- 1.7.4.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/