From nobody Thu Sep 11 22:45:33 2025 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 AB473C001B0 for ; Tue, 8 Aug 2023 16:44:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233287AbjHHQoF (ORCPT ); Tue, 8 Aug 2023 12:44:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34764 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233283AbjHHQnT (ORCPT ); Tue, 8 Aug 2023 12:43:19 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8DE5C55BE for ; Tue, 8 Aug 2023 08:55:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1691510140; x=1723046140; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=myuEuHSAILfOpPq4xlnak3sZ+xUPplX7XLY6m7PLmVQ=; b=CU+03GQQ9mSjVpBtIpL9nud1fkd9DAzhFGu+k+lh+m7G55i9d8ASR8Ik 9/9ISSt5uLa+bI7umvw3dNJyNxVgS4pBXkN47IHc8IFJHkhG80pejRsr4 zF0UB/sQyEt4o433g1kd97JTLAlwOktB+kBWRffWH/mlXXWVOalBD9mcH 0AGEBI8aexYIbsDyKbSxZbzZ1k786UYasaxK90e6gAOj4XtzUxR32tMU6 uIi9zP1jL0+sMhPVL+XsQwoM2ijI6iZa7Z7Byp3HAy/h/rhrSOkJO0FNK lls0OGeMDFsL51hrp3p/KnXNH0J3FNy67epOZrXYfClEJHp/2gVLUCy8J w==; X-IronPort-AV: E=McAfee;i="6600,9927,10795"; a="437078693" X-IronPort-AV: E=Sophos;i="6.01,263,1684825200"; d="scan'208";a="437078693" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Aug 2023 00:50:04 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10795"; a="681146403" X-IronPort-AV: E=Sophos;i="6.01,263,1684825200"; d="scan'208";a="681146403" Received: from kechen-optiplex-9020.bj.intel.com ([10.238.156.126]) by orsmga003.jf.intel.com with ESMTP; 08 Aug 2023 00:50:02 -0700 From: Tina Zhang To: Jason Gunthorpe , Kevin Tian , Lu Baolu , Michael Shavit Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, Tina Zhang Subject: [PATCH 4/5] iommu: Support mm PASID 1:n with sva domains Date: Tue, 8 Aug 2023 15:49:43 +0800 Message-Id: <20230808074944.7825-5-tina.zhang@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20230808074944.7825-1-tina.zhang@intel.com> References: <20230808074944.7825-1-tina.zhang@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Each mm bound to devices gets a PASID and corresponding sva domains allocated in iommu_sva_bind_device(), which are referenced by iommu_mm field of the mm. The PASID is released in __mmdrop(), while a sva domain is released when on one is using it (the reference count is decremented in iommu_sva_unbind_device()). Since the required info of PASID and sva domains is kept in struct iommu_mm_data of a mm, use mm->iommu_mm field instead of the old pasid field in mm struct. The sva domain list is protected by iommu_sva_lock. Besides, this patch removes mm_pasid_init(), as with the introduced iommu_mm structure, initializing mm pasid in mm_init() is unnecessary. Signed-off-by: Tina Zhang --- drivers/iommu/iommu-sva.c | 38 +++++++++++++++++++++++++------------- include/linux/iommu.h | 10 +++------- kernel/fork.c | 1 - 3 files changed, 28 insertions(+), 21 deletions(-) diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c index 0a4a1ed40814..35366f51ad27 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 || @@ -33,11 +34,22 @@ static int iommu_sva_alloc_pasid(struct mm_struct *mm, = ioasid_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; + } + ret =3D ida_alloc_range(&iommu_global_pasid_ida, min, max, GFP_KERNEL); - if (ret < 0) + if (ret < 0) { + kfree(iommu_mm); goto out; + } + + iommu_mm->pasid =3D ret; + mm->iommu_mm =3D iommu_mm; + INIT_LIST_HEAD(&mm->iommu_mm->sva_domains); =20 - mm->pasid =3D ret; ret =3D 0; out: mutex_unlock(&iommu_sva_lock); @@ -82,16 +94,12 @@ struct iommu_sva *iommu_sva_bind_device(struct device *= dev, struct mm_struct *mm =20 mutex_lock(&iommu_sva_lock); /* Search for an existing domain. */ - domain =3D iommu_get_domain_for_dev_pasid(dev, mm_get_pasid(mm), - IOMMU_DOMAIN_SVA); - if (IS_ERR(domain)) { - ret =3D PTR_ERR(domain); - goto out_unlock; - } - - if (domain) { - domain->users++; - goto out; + list_for_each_entry(domain, &mm->iommu_mm->sva_domains, next) { + ret =3D iommu_attach_device_pasid(domain, dev, mm_get_pasid(mm)); + if (!ret) { + domain->users++; + goto out; + } } =20 /* Allocate a new domain and set it on device pasid. */ @@ -105,6 +113,8 @@ struct iommu_sva *iommu_sva_bind_device(struct device *= dev, struct mm_struct *mm if (ret) goto out_free_domain; domain->users =3D 1; + list_add(&domain->next, &mm->iommu_mm->sva_domains); + out: mutex_unlock(&iommu_sva_lock); handle->dev =3D dev; @@ -137,8 +147,9 @@ void iommu_sva_unbind_device(struct iommu_sva *handle) struct device *dev =3D handle->dev; =20 mutex_lock(&iommu_sva_lock); + iommu_detach_device_pasid(domain, dev, pasid); if (--domain->users =3D=3D 0) { - iommu_detach_device_pasid(domain, dev, pasid); + list_del(&domain->next); iommu_domain_free(domain); } mutex_unlock(&iommu_sva_lock); @@ -218,4 +229,5 @@ 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/include/linux/iommu.h b/include/linux/iommu.h index 435d1c1afd23..6a87df6d8637 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -109,6 +109,7 @@ struct iommu_domain { struct { /* IOMMU_DOMAIN_SVA */ struct mm_struct *mm; int users; + struct list_head next; }; }; }; @@ -1177,17 +1178,13 @@ static inline bool tegra_dev_iommu_get_stream_id(st= ruct device *dev, u32 *stream } =20 #ifdef CONFIG_IOMMU_SVA -static inline void mm_pasid_init(struct mm_struct *mm) -{ - mm->pasid =3D IOMMU_PASID_INVALID; -} static inline bool mm_valid_pasid(struct mm_struct *mm) { - return mm->pasid !=3D IOMMU_PASID_INVALID; + return mm->iommu_mm ? true : false; } static inline u32 mm_get_pasid(struct mm_struct *mm) { - return mm->pasid; + return mm->iommu_mm ? mm->iommu_mm->pasid : IOMMU_PASID_INVALID; } void mm_pasid_drop(struct mm_struct *mm); struct iommu_sva *iommu_sva_bind_device(struct device *dev, @@ -1209,7 +1206,6 @@ static inline u32 iommu_sva_get_pasid(struct iommu_sv= a *handle) { return IOMMU_PASID_INVALID; } -static inline void mm_pasid_init(struct mm_struct *mm) {} static inline bool mm_valid_pasid(struct mm_struct *mm) { return false; } static inline u32 mm_get_pasid(struct mm_struct *mm) { diff --git a/kernel/fork.c b/kernel/fork.c index d2e12b6d2b18..f06392dd1ca8 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1274,7 +1274,6 @@ static struct mm_struct *mm_init(struct mm_struct *mm= , struct task_struct *p, mm_init_cpumask(mm); mm_init_aio(mm); mm_init_owner(mm, p); - mm_pasid_init(mm); RCU_INIT_POINTER(mm->exe_file, NULL); mmu_notifier_subscriptions_init(mm); init_tlb_flush_pending(mm); --=20 2.17.1