From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932200AbaCQF5b (ORCPT ); Mon, 17 Mar 2014 01:57:31 -0400 Received: from mail-ob0-f181.google.com ([209.85.214.181]:58342 "EHLO mail-ob0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753168AbaCQFzj (ORCPT ); Mon, 17 Mar 2014 01:55:39 -0400 From: "Nicholas A. Bellinger" To: target-devel Cc: linux-scsi , linux-kernel , kvm-devel , "Michael S. Tsirkin" , Paolo Bonzini , "Martin K. Petersen" , Christoph Hellwig , Hannes Reinecke , Sagi Grimberg , "H. Peter Anvin" , Nicholas Bellinger , Sagi Grimberg Subject: [RFCv2 4/7] vhost/scsi: Add T10 PI IOV -> SGL memory mapping logic Date: Mon, 17 Mar 2014 05:32:58 +0000 Message-Id: <1395034381-656-5-git-send-email-nab@daterainc.com> X-Mailer: git-send-email 1.7.2.5 In-Reply-To: <1395034381-656-1-git-send-email-nab@daterainc.com> References: <1395034381-656-1-git-send-email-nab@daterainc.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nicholas Bellinger This patch adds vhost_scsi_map_iov_to_prot() to perform the mapping of T10 data integrity memory between virtio iov + struct scatterlist using get_user_pages_fast() following existing code. As with vhost_scsi_map_iov_to_sgl(), this does sanity checks against the total prot_sgl_count vs. pre-allocated SGLs, and loops across protection iovs using vhost_scsi_map_to_sgl() to perform the actual memory mapping. Also update tcm_vhost_release_cmd() to release associated tvc_prot_sgl[] struct page. Cc: Michael S. Tsirkin Cc: Paolo Bonzini Cc: Martin K. Petersen Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Sagi Grimberg Cc: H. Peter Anvin Signed-off-by: Nicholas Bellinger --- drivers/vhost/scsi.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 47 insertions(+), 1 deletions(-) diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index a2cb289..f720709 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -80,6 +80,7 @@ struct tcm_vhost_cmd { u64 tvc_tag; /* The number of scatterlists associated with this cmd */ u32 tvc_sgl_count; + u32 tvc_prot_sgl_count; /* Saved unpacked SCSI LUN for tcm_vhost_submission_work() */ u32 tvc_lun; /* Pointer to the SGL formatted memory from virtio-scsi */ @@ -458,12 +459,16 @@ static void tcm_vhost_release_cmd(struct se_cmd *se_cmd) struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd, struct tcm_vhost_cmd, tvc_se_cmd); struct se_session *se_sess = se_cmd->se_sess; + int i; if (tv_cmd->tvc_sgl_count) { - u32 i; for (i = 0; i < tv_cmd->tvc_sgl_count; i++) put_page(sg_page(&tv_cmd->tvc_sgl[i])); } + if (tv_cmd->tvc_prot_sgl_count) { + for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++) + put_page(sg_page(&tv_cmd->tvc_prot_sgl[i])); + } tcm_vhost_put_inflight(tv_cmd->inflight); percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag); @@ -856,6 +861,47 @@ vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *cmd, return 0; } +static int +vhost_scsi_map_iov_to_prot(struct tcm_vhost_cmd *cmd, + struct iovec *iov, + int niov, + bool write) +{ + struct scatterlist *prot_sg = cmd->tvc_prot_sgl; + unsigned int prot_sgl_count = 0; + int ret, i; + + for (i = 0; i < niov; i++) + prot_sgl_count += iov_num_pages(&iov[i]); + + if (prot_sgl_count > TCM_VHOST_PREALLOC_PROT_SGLS) { + pr_err("vhost_scsi_map_iov_to_prot() sgl_count: %u greater than" + " preallocated TCM_VHOST_PREALLOC_PROT_SGLS: %u\n", + prot_sgl_count, TCM_VHOST_PREALLOC_PROT_SGLS); + return -ENOBUFS; + } + + pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__, + prot_sg, prot_sgl_count); + sg_init_table(prot_sg, prot_sgl_count); + cmd->tvc_prot_sgl_count = prot_sgl_count; + + for (i = 0; i < niov; i++) { + ret = vhost_scsi_map_to_sgl(cmd, prot_sg, prot_sgl_count, &iov[i], + cmd->tvc_upages, write); + if (ret < 0) { + for (i = 0; i < cmd->tvc_prot_sgl_count; i++) + put_page(sg_page(&cmd->tvc_prot_sgl[i])); + + cmd->tvc_prot_sgl_count = 0; + return ret; + } + prot_sg += ret; + prot_sgl_count -= ret; + } + return 0; +} + static void tcm_vhost_submission_work(struct work_struct *work) { struct tcm_vhost_cmd *cmd = -- 1.7.2.5