From patchwork Fri May 19 20:32:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacob Pan X-Patchwork-Id: 13248819 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 09082C77B75 for ; Fri, 19 May 2023 20:28:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231173AbjESU2C (ORCPT ); Fri, 19 May 2023 16:28:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58816 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230477AbjESU2A (ORCPT ); Fri, 19 May 2023 16:28:00 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DD24119A; Fri, 19 May 2023 13:27:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1684528078; x=1716064078; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=XALtxzpKtpRxLIztaMGye6Hq0U/QQOFMvurHPzjt4es=; b=CWagWlNK0dWmv1F3OOCs6d+V9zki+rQTQc2qvI3HobqHnETQZysru7O6 ZfMLT7SJxrPSkEv+JV982BswJyliQQgybK05smMP6HtVULbOnwGLWJpE4 oE3Avd7VdVgkZ8ltqBuoKNO+k0eFV0S7PdOhle4XFtpxxSCFeA80AfLci 8GrLWTN/pFc+B+e1PTW8znHnhz9WokAa5/IY4a9MOLYbXxrgo7I3YHl4H Db0eoNPp9/buh1tdaE+XzDn97rYlmnw8AqKrt2c3dpKNOY21huurk3+yu aBwFL/KykYaCrPEc6fvcYF4YrzFrYNk6ZPLycLyrJpqFYexLx5fTsBi4l A==; X-IronPort-AV: E=McAfee;i="6600,9927,10715"; a="418175381" X-IronPort-AV: E=Sophos;i="6.00,177,1681196400"; d="scan'208";a="418175381" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 May 2023 13:27:56 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10715"; a="876967803" X-IronPort-AV: E=Sophos;i="6.00,177,1681196400"; d="scan'208";a="876967803" Received: from srinivas-otcpl-7600.jf.intel.com (HELO jacob-builder.jf.intel.com) ([10.54.97.184]) by orsmga005.jf.intel.com with ESMTP; 19 May 2023 13:27:56 -0700 From: Jacob Pan To: LKML , iommu@lists.linux.dev, Jason Gunthorpe , "Lu Baolu" , Joerg Roedel , dmaengine@vger.kernel.org, vkoul@kernel.org Cc: "Robin Murphy" , "Will Deacon" , David Woodhouse , Raj Ashok , "Tian, Kevin" , Yi Liu , "Yu, Fenghua" , Dave Jiang , Tony Luck , "Zanussi, Tom" , narayan.ranganathan@intel.com, Jacob Pan Subject: [PATCH v6 4/4] dmaengine/idxd: Re-enable kernel workqueue under DMA API Date: Fri, 19 May 2023 13:32:23 -0700 Message-Id: <20230519203223.2777255-5-jacob.jun.pan@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230519203223.2777255-1-jacob.jun.pan@linux.intel.com> References: <20230519203223.2777255-1-jacob.jun.pan@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Kernel workqueues were disabled due to flawed use of kernel VA and SVA API. Now that we have the support for attaching PASID to the device's default domain and the ability to reserve global PASIDs from SVA APIs, we can re-enable the kernel work queues and use them under DMA API. We also use non-privileged access for in-kernel DMA to be consistent with the IOMMU settings. Consequently, interrupt for user privilege is enabled for work completion IRQs. Link:https://lore.kernel.org/linux-iommu/20210511194726.GP1002214@nvidia.com/ Reviewed-by: Dave Jiang Reviewed-by: Fenghua Yu Signed-off-by: Jacob Pan Reviewed-by: Lu Baolu --- drivers/dma/idxd/device.c | 30 ++++---------------- drivers/dma/idxd/dma.c | 5 ++-- drivers/dma/idxd/init.c | 60 ++++++++++++++++++++++++++++++++++++--- drivers/dma/idxd/sysfs.c | 7 ----- 4 files changed, 64 insertions(+), 38 deletions(-) diff --git a/drivers/dma/idxd/device.c b/drivers/dma/idxd/device.c index 5abbcc61c528..66b6665a45cb 100644 --- a/drivers/dma/idxd/device.c +++ b/drivers/dma/idxd/device.c @@ -299,21 +299,6 @@ void idxd_wqs_unmap_portal(struct idxd_device *idxd) } } -static void __idxd_wq_set_priv_locked(struct idxd_wq *wq, int priv) -{ - struct idxd_device *idxd = wq->idxd; - union wqcfg wqcfg; - unsigned int offset; - - offset = WQCFG_OFFSET(idxd, wq->id, WQCFG_PRIVL_IDX); - spin_lock(&idxd->dev_lock); - wqcfg.bits[WQCFG_PRIVL_IDX] = ioread32(idxd->reg_base + offset); - wqcfg.priv = priv; - wq->wqcfg->bits[WQCFG_PRIVL_IDX] = wqcfg.bits[WQCFG_PRIVL_IDX]; - iowrite32(wqcfg.bits[WQCFG_PRIVL_IDX], idxd->reg_base + offset); - spin_unlock(&idxd->dev_lock); -} - static void __idxd_wq_set_pasid_locked(struct idxd_wq *wq, int pasid) { struct idxd_device *idxd = wq->idxd; @@ -1423,15 +1408,14 @@ int drv_enable_wq(struct idxd_wq *wq) } /* - * In the event that the WQ is configurable for pasid and priv bits. - * For kernel wq, the driver should setup the pasid, pasid_en, and priv bit. - * However, for non-kernel wq, the driver should only set the pasid_en bit for - * shared wq. A dedicated wq that is not 'kernel' type will configure pasid and + * In the event that the WQ is configurable for pasid, the driver + * should setup the pasid, pasid_en bit. This is true for both kernel + * and user shared workqueues. There is no need to setup priv bit in + * that in-kernel DMA will also do user privileged requests. + * A dedicated wq that is not 'kernel' type will configure pasid and * pasid_en later on so there is no need to setup. */ if (test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags)) { - int priv = 0; - if (wq_pasid_enabled(wq)) { if (is_idxd_wq_kernel(wq) || wq_shared(wq)) { u32 pasid = wq_dedicated(wq) ? idxd->pasid : 0; @@ -1439,10 +1423,6 @@ int drv_enable_wq(struct idxd_wq *wq) __idxd_wq_set_pasid_locked(wq, pasid); } } - - if (is_idxd_wq_kernel(wq)) - priv = 1; - __idxd_wq_set_priv_locked(wq, priv); } rc = 0; diff --git a/drivers/dma/idxd/dma.c b/drivers/dma/idxd/dma.c index eb35ca313684..07623fb0f52f 100644 --- a/drivers/dma/idxd/dma.c +++ b/drivers/dma/idxd/dma.c @@ -75,9 +75,10 @@ static inline void idxd_prep_desc_common(struct idxd_wq *wq, hw->xfer_size = len; /* * For dedicated WQ, this field is ignored and HW will use the WQCFG.priv - * field instead. This field should be set to 1 for kernel descriptors. + * field instead. This field should be set to 0 for kernel descriptors + * since kernel DMA on VT-d supports "user" privilege only. */ - hw->priv = 1; + hw->priv = 0; hw->completion_addr = compl; } diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c index 1aa823974cda..bd7b9bd40f0a 100644 --- a/drivers/dma/idxd/init.c +++ b/drivers/dma/idxd/init.c @@ -550,14 +550,65 @@ static struct idxd_device *idxd_alloc(struct pci_dev *pdev, struct idxd_driver_d static int idxd_enable_system_pasid(struct idxd_device *idxd) { - return -EOPNOTSUPP; + struct pci_dev *pdev = idxd->pdev; + struct device *dev = &pdev->dev; + struct iommu_domain *domain; + union gencfg_reg gencfg; + ioasid_t pasid; + int ret; + + /* + * Attach a global PASID to the DMA domain so that we can use ENQCMDS + * to submit work on buffers mapped by DMA API. + */ + domain = iommu_get_domain_for_dev(dev); + if (!domain) + return -EPERM; + + pasid = iommu_alloc_global_pasid_dev(dev); + if (pasid == IOMMU_PASID_INVALID) + return -ENOSPC; + + /* + * DMA domain is owned by the driver, it should support all valid + * types such as DMA-FQ, identity, etc. + */ + ret = iommu_attach_device_pasid(domain, dev, pasid); + if (ret) { + dev_err(dev, "failed to attach device pasid %d, domain type %d", + pasid, domain->type); + iommu_free_global_pasid(pasid); + return ret; + } + + /* Since we set user privilege for kernel DMA, enable completion IRQ */ + gencfg.bits = ioread32(idxd->reg_base + IDXD_GENCFG_OFFSET); + gencfg.user_int_en = 1; + iowrite32(gencfg.bits, idxd->reg_base + IDXD_GENCFG_OFFSET); + idxd->pasid = pasid; + + return ret; } static void idxd_disable_system_pasid(struct idxd_device *idxd) { + struct pci_dev *pdev = idxd->pdev; + struct device *dev = &pdev->dev; + struct iommu_domain *domain; + union gencfg_reg gencfg; + + domain = iommu_get_domain_for_dev(dev); + if (!domain) + return; + + iommu_detach_device_pasid(domain, dev, idxd->pasid); + iommu_free_global_pasid(idxd->pasid); - iommu_sva_unbind_device(idxd->sva); + gencfg.bits = ioread32(idxd->reg_base + IDXD_GENCFG_OFFSET); + gencfg.user_int_en = 0; + iowrite32(gencfg.bits, idxd->reg_base + IDXD_GENCFG_OFFSET); idxd->sva = NULL; + idxd->pasid = IOMMU_PASID_INVALID; } static int idxd_enable_sva(struct pci_dev *pdev) @@ -600,8 +651,9 @@ static int idxd_probe(struct idxd_device *idxd) } else { set_bit(IDXD_FLAG_USER_PASID_ENABLED, &idxd->flags); - if (idxd_enable_system_pasid(idxd)) - dev_warn(dev, "No in-kernel DMA with PASID.\n"); + rc = idxd_enable_system_pasid(idxd); + if (rc) + dev_warn(dev, "No in-kernel DMA with PASID. %d\n", rc); else set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags); } diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c index 293739ac5596..63f6966c51aa 100644 --- a/drivers/dma/idxd/sysfs.c +++ b/drivers/dma/idxd/sysfs.c @@ -948,13 +948,6 @@ static ssize_t wq_name_store(struct device *dev, if (strlen(buf) > WQ_NAME_SIZE || strlen(buf) == 0) return -EINVAL; - /* - * This is temporarily placed here until we have SVM support for - * dmaengine. - */ - if (wq->type == IDXD_WQT_KERNEL && device_pasid_enabled(wq->idxd)) - return -EOPNOTSUPP; - input = kstrndup(buf, count, GFP_KERNEL); if (!input) return -ENOMEM;