From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=95.215.58.97 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794170895; b=DPasZAG1PO1PfpADPS3ccWR/DAoqB4Umc6Ali3pkRhN63khW/SNxdzZR7+1LEqSM4Rpg M+85llAHeppbVDz2O3VkcuBwcEwjHAzs6PorTwhW0sn/r0wwPfXICRpwbGVUBxPu60cHW ukwzeY3vDGyzZR4nVajnFldWQMlNfzAZxZbApOzRrOkZ7afgIYSvjIxgeZTb1YVp1rLF0 /reFeHBMh+SVWOcjz/fZwa1wD4GARHQwBIZOcyPF077/tkf50Mvi80YoVIQ6XG+vfn6Tp Su9JPglLFCjiYIFHALaytuoGhF1hxq4X2z9dKIYrA7+OzhCkL5+FcdPVYjAa0PWZW/w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794170895; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:From:To:Cc:Subject:Date:Message-ID: X-Mailer:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=YVm0hLTen/l7MjbTkGxRRCAEivtbhd4NAn6q7xWAEYg=; b=s1goywKgupsWFAljesZpdBVAaooF/Lu1h381XLVQOaTXpmSVirQBklSLQneK9EFgohwd njs4rIT0/1z+Gq7WHjAvniRm6yTl99uw35fdr4s8hrwiImt5p7NUxwAIJEzVdfLwdtx99 7RROHvBvhpDAx4IyasQ5eZUlg3riK/YmvS6K4lYyFAMoCBq9+F8bTEwtpO3AxuHBcd5eS RvsuQ4NEVvxFo3imISdImLfGxjfxboWo/hmEh0U/cKzV/aVuAMGOR29chuR1HgvkLx3yQ LKFmSNoWBJlOOYTRQFHvC6fY9J7owKiu/x0FRXll2L44CdcYT+3ZoanEcfij55VRPVA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=DgYpzd9k; arc=none smtp.remote-ip=95.215.58.97 Received: from mta1.migadu.com (out-97.mta1.migadu.com [95.215.58.97]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BD486606A326 for ; Sun, 8 Nov 2026 20:48:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org BD486606A326 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=DgYpzd9k X-Envelope-To: linux-scsi@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=WSIUiiRUDwnbfq8m1M5V5dJ7+FsoCilapxmskdaABhM=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1794170893; v=1; x=1794775693; b=DgYpzd9kCd3Sn+Kt3Bbl5berkg+7XYedvheSZ8rQAp4oo7XAEtIvOmNXOX9huTfNbMkFfUoN TBWqsIGXeu7JKy8dRAAMTNxcZrgE71JwKQhAs8nv7wiV6Eo2uZU2REhBcXGwxk+kzPwy6dkkLK7 Ycw3qhIJkqYBjPkRlSpZSX84= X-Envelope-To: linux-scsi@vger.kernel.org Received: by mta10.migadu.com with ESMTPS id 512cbddf7a48e872; Sun, 08 Nov 2026 20:48:13 +0000 X-Mizu-Trace-ID: 512cbddf7a48e872 X-Migadu-Flow: FLOW_OUT From: John Garry To: james.bottomley@hansenpartnership.com, mkp@kernel.org Cc: hare@suse.com, linux-nvme@lists.infradead.org, linux-scsi@vger.kernel.org, snitzer@kernel.org, jmeneghi@redhat.com, bmarzins@redhat.com, dm-devel@lists.linux.dev, hch@lst.de, michael.christie@oracle.com, John Garry Subject: [PATCH v9 15/29] scsi-multipath: support iopolicy Date: Sun, 8 Nov 2026 20:47:19 +0000 Message-ID: <20261108204733.557995-16-john.garry@linux.dev> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20261108204733.557995-1-john.garry@linux.dev> References: <20261108204733.557995-1-john.garry@linux.dev> X-Mailing-List: linux-scsi@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add support to set the multipath iopolicy. The iopolicy member is per scsi_mpath_head structure. A module param is added so that the default iopolicy may be set. Signed-off-by: John Garry --- drivers/scsi/scsi_multipath.c | 52 +++++++++++++++++++++++++++++++++++ include/scsi/scsi_multipath.h | 3 ++ 2 files changed, 55 insertions(+) diff --git a/drivers/scsi/scsi_multipath.c b/drivers/scsi/scsi_multipath.c index 092975e0aca1..baf4ca73f8c9 100644 --- a/drivers/scsi/scsi_multipath.c +++ b/drivers/scsi/scsi_multipath.c @@ -61,6 +61,23 @@ static const struct kernel_param_ops multipath_param_ops = { module_param_cb(multipath, &multipath_param_ops, &scsi_multipath, 0444); MODULE_PARM_DESC(multipath, "turn on native multipath support, options: on, off, always"); +static enum mpath_iopolicy_e iopolicy = MPATH_IOPOLICY_NUMA; + +static int scsi_mpath_set_iopolicy_param(const char *val, const struct kernel_param *kp) +{ + return mpath_set_iopolicy(val, &iopolicy); +} + +static int scsi_mpath_get_iopolicy_param(char *buf, const struct kernel_param *kp) +{ + return mpath_get_iopolicy(buf, iopolicy); +} + +module_param_call(multipath_iopolicy, scsi_mpath_set_iopolicy_param, + scsi_mpath_get_iopolicy_param, &iopolicy, 0644); +MODULE_PARM_DESC(multipath_iopolicy, + "Default multipath I/O policy; 'numa' (default), 'round-robin' or 'queue-depth'"); + static int scsi_mpath_unique_lun_id(struct scsi_device *sdev) { struct scsi_mpath_device *scsi_mpath_dev = sdev->scsi_mpath_dev; @@ -101,8 +118,41 @@ static ssize_t scsi_mpath_device_vpd_id_show(struct device *dev, } static DEVICE_ATTR(vpd_id, S_IRUGO, scsi_mpath_device_vpd_id_show, NULL); +static ssize_t scsi_mpath_device_iopolicy_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + struct scsi_mpath_head *scsi_mpath_head = + container_of(dev, struct scsi_mpath_head, dev); + struct mpath_head *mpath_head = &scsi_mpath_head->mpath_head; + + if (!mpath_iopolicy_store(&scsi_mpath_head->iopolicy, buf)) + return -EINVAL; + + mpath_clear_paths(mpath_head); + mpath_schedule_requeue_work(mpath_head); + /* + * Ensure requeue work completes, as this work could run later when + * the mpath_head is gone. + */ + flush_work(&mpath_head->requeue_work); + return count; +} + +static ssize_t scsi_mpath_device_iopolicy_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct scsi_mpath_head *scsi_mpath_head = + container_of(dev, struct scsi_mpath_head, dev); + + return mpath_iopolicy_show(&scsi_mpath_head->iopolicy, buf); +} + +static DEVICE_ATTR(iopolicy, S_IRUGO | S_IWUSR, + scsi_mpath_device_iopolicy_show, scsi_mpath_device_iopolicy_store); + static struct attribute *scsi_mpath_device_attrs[] = { &dev_attr_vpd_id.attr, + &dev_attr_iopolicy.attr, NULL }; @@ -206,6 +256,8 @@ static struct scsi_mpath_head *scsi_mpath_alloc_head(char *vpd_id) if (mpath_head_init(&scsi_mpath_head->mpath_head)) goto out_free; scsi_mpath_head->mpath_head.mpdt = &smpdt; + scsi_mpath_head->iopolicy = iopolicy; + scsi_mpath_head->mpath_head.iopolicy = &scsi_mpath_head->iopolicy; strscpy(scsi_mpath_head->vpd_id, vpd_id, SCSI_MPATH_DEVICE_ID_LEN); diff --git a/include/scsi/scsi_multipath.h b/include/scsi/scsi_multipath.h index d224a15ce9c2..d6f290b84f7f 100644 --- a/include/scsi/scsi_multipath.h +++ b/include/scsi/scsi_multipath.h @@ -25,6 +25,7 @@ struct scsi_mpath_head { struct list_head entry; struct ida ida; struct kref ref; + enum mpath_iopolicy_e iopolicy; struct device dev; int index; }; @@ -40,6 +41,8 @@ struct scsi_mpath_device { #define to_scsi_mpath_device(d) \ container_of(d, struct scsi_mpath_device, mpath_device) +#define to_scsi_mpath_head(d) \ + container_of(d, struct scsi_mpath_head, mpath_head) int scsi_mpath_dev_alloc(struct scsi_device *sdev); void scsi_mpath_dev_release(struct scsi_device *sdev); -- 2.43.0