From nobody Mon Feb 9 09:10:05 2026 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 A57B9EB64DC for ; Fri, 7 Jul 2023 01:35:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231991AbjGGBf3 (ORCPT ); Thu, 6 Jul 2023 21:35:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42612 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231921AbjGGBf0 (ORCPT ); Thu, 6 Jul 2023 21:35:26 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9E1BC2101 for ; Thu, 6 Jul 2023 18:35:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1688693715; x=1720229715; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=1h7edKtoFv8FxuKLDfoJ9kk0foTEvF67RC9h6LudYHI=; b=FupDQZbQ2il+emcJsNbzJnh7q1PNZADTE1NrfJ7FYPnGsq7w2vQerWhn e7lFkZKYqHzqZGmJj273GfbtmqNfQiFIaEJgczfrppK8mRjA4W0J7nTeN unPUdmxEdGHUd8gCdkBH/BYkfw1kxbViFb8ZaAKZ2zp+ke6B5e9llS0DE JJlzUfU8LwnXMNplaeUFtODQI79OEY5lOM4XhhNXa/m24LeoDq+f+K0uE Z6S+1TWuFk3X/MV39hXlK9OEd3Ca2ZJJ8lZVbfIqTZCFY9/1RE/IAbuTe vgEbg9DXuhV0i2YGA6hyh1TocFtkDGU2sATcI1ngu9LXwydIkcAJKNVUz Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10763"; a="429832309" X-IronPort-AV: E=Sophos;i="6.01,187,1684825200"; d="scan'208";a="429832309" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jul 2023 18:35:14 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10763"; a="893791362" X-IronPort-AV: E=Sophos;i="6.01,187,1684825200"; d="scan'208";a="893791362" Received: from fengj-mobl.ccr.corp.intel.com (HELO tinazhan-desk1.www.tendawifi.com) ([10.254.210.124]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jul 2023 18:35:11 -0700 From: Tina Zhang To: Jason Gunthorpe , Kevin Tian , Joerg Roedel , Will Deacon , Lu Baolu , Michael Shavit Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, Tina Zhang Subject: [RFC PATCH 5/6] iommu: Support mm PASID 1:1 with sva domain Date: Fri, 7 Jul 2023 09:34:40 +0800 Message-Id: <20230707013441.365583-6-tina.zhang@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230707013441.365583-1-tina.zhang@intel.com> References: <20230707013441.365583-1-tina.zhang@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Each mm bound to devices gets a PASID and a corresponding sva domain allocated in iommu_sva_bind_device(), which are referenced by iommu_mm field of the mm. And that PASID and sva domain get released in iommu_sva_ unbind_device() when no devices are binding to that mm. As a result, during the life cycle, sva domain has 1:1 with mm PASID. Since the required info of PASID and sva domain are kept in struct iommu_mm_data of a mm, use mm->iommu_mm field instead of the old pasid field in mm struct. Signed-off-by: Tina Zhang --- drivers/iommu/iommu-sva.c | 54 +++++++++++++++++++++++++++------------ drivers/iommu/iommu.c | 1 + include/linux/iommu.h | 8 +++--- 3 files changed, 42 insertions(+), 21 deletions(-) diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c index 7a41b6510e385..342d8ba9ab479 100644 --- a/drivers/iommu/iommu-sva.c +++ b/drivers/iommu/iommu-sva.c @@ -15,6 +15,7 @@ static DEFINE_IDA(iommu_global_pasid_ida); /* Allocate a PASID for the mm within range (inclusive) */ static int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min, ioasi= d_t max) { + struct iommu_mm_data *iommu_mm =3D NULL; int ret =3D 0; =20 if (min =3D=3D IOMMU_PASID_INVALID || @@ -33,9 +34,18 @@ static int iommu_sva_alloc_pasid(struct mm_struct *mm, i= oasid_t min, ioasid_t ma goto out; } =20 + iommu_mm =3D kzalloc(sizeof(struct iommu_mm_data), GFP_KERNEL); + if (!iommu_mm) { + ret =3D -ENOMEM; + goto out; + } + mm->iommu_mm =3D iommu_mm; + ret =3D ida_alloc_range(&iommu_global_pasid_ida, min, max, GFP_KERNEL); - if (ret < min) + if (ret < min) { + kfree(iommu_mm); goto out; + } mm_set_pasid(mm, ret); ret =3D 0; out: @@ -61,7 +71,7 @@ static int iommu_sva_alloc_pasid(struct mm_struct *mm, io= asid_t min, ioasid_t ma */ struct iommu_sva *iommu_sva_bind_device(struct device *dev, struct mm_stru= ct *mm) { - struct iommu_domain *domain; + struct iommu_domain *domain, *sva_domain =3D mm->iommu_mm->sva_domain; struct iommu_sva *handle; ioasid_t max_pasids; int ret; @@ -88,31 +98,41 @@ struct iommu_sva *iommu_sva_bind_device(struct device *= dev, struct mm_struct *mm goto out_unlock; } =20 - if (domain) { - domain->users++; - goto out; + if (unlikely(domain)) { + /* Re-attach the device to the same domain? */ + if (domain =3D=3D sva_domain) { + goto out; + } else { + /* Didn't get detached from the previous domain? */ + ret =3D -EBUSY; + goto out_unlock; + } } =20 - /* Allocate a new domain and set it on device pasid. */ - domain =3D iommu_sva_domain_alloc(dev, mm); - if (!domain) { - ret =3D -ENOMEM; - goto out_unlock; + if (sva_domain) { + sva_domain->users++; + } else { + /* Allocate a new domain and set it on device pasid. */ + sva_domain =3D iommu_sva_domain_alloc(dev, mm); + if (!sva_domain) { + ret =3D -ENOMEM; + goto out_unlock; + } + sva_domain->users =3D 1; } =20 - ret =3D iommu_attach_device_pasid(domain, dev, mm_get_pasid(mm)); + ret =3D iommu_attach_device_pasid(sva_domain, dev, mm_get_pasid(mm)); if (ret) goto out_free_domain; - domain->users =3D 1; out: mutex_unlock(&iommu_sva_lock); handle->dev =3D dev; - handle->domain =3D domain; + handle->domain =3D sva_domain; =20 return handle; =20 out_free_domain: - iommu_domain_free(domain); + iommu_domain_free(sva_domain); out_unlock: mutex_unlock(&iommu_sva_lock); kfree(handle); @@ -136,10 +156,9 @@ void iommu_sva_unbind_device(struct iommu_sva *handle) struct device *dev =3D handle->dev; =20 mutex_lock(&iommu_sva_lock); - if (--domain->users =3D=3D 0) { - iommu_detach_device_pasid(domain, dev, pasid); + iommu_detach_device_pasid(domain, dev, pasid); + if (--domain->users =3D=3D 0) iommu_domain_free(domain); - } mutex_unlock(&iommu_sva_lock); kfree(handle); } @@ -217,4 +236,5 @@ void mm_pasid_drop(struct mm_struct *mm) return; =20 ida_free(&iommu_global_pasid_ida, mm_get_pasid(mm)); + kfree(mm->iommu_mm); } diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 35fa1c1b12826..2f55a157b1f15 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -3393,5 +3393,6 @@ struct iommu_domain *iommu_sva_domain_alloc(struct de= vice *dev, domain->iopf_handler =3D iommu_sva_handle_iopf; domain->fault_data =3D mm; =20 + mm->iommu_mm->sva_domain =3D domain; return domain; } diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 20135912584ba..1511ded7bc910 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -1175,20 +1175,20 @@ static inline bool tegra_dev_iommu_get_stream_id(st= ruct device *dev, u32 *stream #ifdef CONFIG_IOMMU_SVA static inline void mm_pasid_init(struct mm_struct *mm) { - mm->pasid =3D IOMMU_PASID_INVALID; + mm->iommu_mm =3D &default_iommu_mm; } static inline bool mm_valid_pasid(struct mm_struct *mm) { - return mm->pasid !=3D IOMMU_PASID_INVALID; + return mm->iommu_mm->pasid !=3D IOMMU_PASID_INVALID; } static inline u32 mm_get_pasid(struct mm_struct *mm) { - return mm->pasid; + return mm->iommu_mm->pasid; } =20 static inline void mm_set_pasid(struct mm_struct *mm, u32 pasid) { - mm->pasid =3D pasid; + mm->iommu_mm->pasid =3D pasid; } void mm_pasid_drop(struct mm_struct *mm); struct iommu_sva *iommu_sva_bind_device(struct device *dev, --=20 2.34.1