From patchwork Thu Jun 9 10:29:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Garry X-Patchwork-Id: 12875190 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A89AC43334 for ; Thu, 9 Jun 2022 10:36:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242225AbiFIKgs (ORCPT ); Thu, 9 Jun 2022 06:36:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58908 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242304AbiFIKgO (ORCPT ); Thu, 9 Jun 2022 06:36:14 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D9522109F9; Thu, 9 Jun 2022 03:36:11 -0700 (PDT) Received: from fraeml734-chm.china.huawei.com (unknown [172.18.147.201]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4LJgP55ZrNz6813w; Thu, 9 Jun 2022 18:31:21 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml734-chm.china.huawei.com (10.206.15.215) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 9 Jun 2022 12:36:09 +0200 Received: from localhost.localdomain (10.69.192.58) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 9 Jun 2022 11:36:06 +0100 From: John Garry To: , , , , , , CC: , , , , , John Garry Subject: [PATCH RFC v2 04/18] scsi: core: Add support to send reserved commands Date: Thu, 9 Jun 2022 18:29:05 +0800 Message-ID: <1654770559-101375-5-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 2.8.1 In-Reply-To: <1654770559-101375-1-git-send-email-john.garry@huawei.com> References: <1654770559-101375-1-git-send-email-john.garry@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.69.192.58] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Add a method to queue reserved commands. TODO: - fix timeout handler to call into reserved commands - We don't clear host_scribble for libata qc, but we should be able to drop this if we store libata qc in the scsi cmnd priv_data Signed-off-by: John Garry --- drivers/scsi/hosts.c | 6 ++++++ drivers/scsi/scsi_lib.c | 32 ++++++++++++++++++++++++++++++++ include/scsi/scsi_cmnd.h | 5 +++++ include/scsi/scsi_host.h | 1 + 4 files changed, 44 insertions(+) diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 27296addaf63..5c9b05a8fec8 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -221,6 +221,12 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev, goto fail; } + if (shost->nr_reserved_cmds && !sht->reserved_queuecommand) { + shost_printk(KERN_ERR, shost, + "nr_reserved_cmds set but no method to queue\n"); + goto fail; + } + /* Use min_t(int, ...) in case shost->can_queue exceeds SHRT_MAX */ shost->cmd_per_lun = min_t(int, shost->cmd_per_lun, shost->can_queue); diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index f6e53c6d913c..8c8b4c6767d9 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1422,6 +1422,16 @@ static void scsi_complete(struct request *rq) struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); enum scsi_disposition disposition; + if (scsi_is_reserved_cmd(cmd)) { + struct scsi_device *sdev = cmd->device; + + scsi_mq_uninit_cmd(cmd); + scsi_device_unbusy(sdev, cmd); + __blk_mq_end_request(rq, 0); + + return; + } + INIT_LIST_HEAD(&cmd->eh_entry); atomic_inc(&cmd->device->iodone_cnt); @@ -1706,6 +1716,28 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx, WARN_ON_ONCE(cmd->budget_token < 0); + if (scsi_is_reserved_cmd(cmd)) { + unsigned char *host_scribble = cmd->host_scribble; + + if (!(req->rq_flags & RQF_DONTPREP)) { + ret = scsi_prepare_cmd(req); + if (ret != BLK_STS_OK) { + + goto out_dec_host_busy; + } + + req->rq_flags |= RQF_DONTPREP; + } else { + clear_bit(SCMD_STATE_COMPLETE, &cmd->state); + } + + cmd->host_scribble = host_scribble; + + blk_mq_start_request(req); + + return shost->hostt->reserved_queuecommand(shost, cmd); + } + /* * If the device is not in running state we will reject some or all * commands. diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index 1e80e70dfa92..e47df5836070 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -152,6 +152,11 @@ static inline void *scsi_cmd_priv(struct scsi_cmnd *cmd) return cmd + 1; } +static inline bool scsi_is_reserved_cmd(struct scsi_cmnd *cmd) +{ + return blk_mq_is_reserved_rq(scsi_cmd_to_rq(cmd)); +} + void scsi_done(struct scsi_cmnd *cmd); void scsi_done_direct(struct scsi_cmnd *cmd); diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index 149dcbd4125e..88c8504395c8 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -73,6 +73,7 @@ struct scsi_host_template { * STATUS: REQUIRED */ int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *); + int (* reserved_queuecommand)(struct Scsi_Host *, struct scsi_cmnd *); /* * The commit_rqs function is used to trigger a hardware