From nobody Thu Feb 12 07:59:46 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 6CF76EED61D for ; Fri, 15 Sep 2023 16:59:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234756AbjIOQ6m (ORCPT ); Fri, 15 Sep 2023 12:58:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59738 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234435AbjIOQ63 (ORCPT ); Fri, 15 Sep 2023 12:58:29 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 91805211E for ; Fri, 15 Sep 2023 09:58:23 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7A023C15; Fri, 15 Sep 2023 09:59:00 -0700 (PDT) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 2912D3F5A1; Fri, 15 Sep 2023 09:58:22 -0700 (PDT) From: Robin Murphy To: joro@8bytes.org, will@kernel.org Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, jgg@nvidia.com, baolu.lu@linux.intel.com Subject: [PATCH v3 1/7] iommu: Factor out some helpers Date: Fri, 15 Sep 2023 17:58:05 +0100 Message-Id: X-Mailer: git-send-email 2.39.2.101.g768bb238c484.dirty In-Reply-To: References: 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" The pattern for picking the first device out of the group list is repeated a few times now, so it's clearly worth factoring out, which also helps hide the iommu_group_dev detail from places that don't need to know. Similarly, the safety check for dev_iommu_ops() at certain public interfaces starts looking a bit repetitive, and might not be completely obvious at first glance, so let's factor that out for clarity as well, in preparation for more uses of both. Reviewed-by: Lu Baolu Signed-off-by: Robin Murphy --- v3: Rename dev_iommu_ops_valid() to reflect what it's actually checking, rather than an implied consequence. --- drivers/iommu/iommu.c | 40 +++++++++++++++++++++++++--------------- 1 file changed, 25 insertions(+), 15 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 3bfc56df4f78..4566d0001cd3 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -363,6 +363,15 @@ static void dev_iommu_free(struct device *dev) kfree(param); } =20 +/* + * Internal equivalent of device_iommu_mapped() for when we care that a de= vice + * actually has API ops, and don't want false positives from VFIO-only gro= ups. + */ +static bool dev_has_iommu(struct device *dev) +{ + return dev->iommu && dev->iommu->iommu_dev; +} + static u32 dev_iommu_get_max_pasids(struct device *dev) { u32 max_pasids =3D 0, bits =3D 0; @@ -614,7 +623,7 @@ static void __iommu_group_remove_device(struct device *= dev) =20 list_del(&device->list); __iommu_group_free_device(group, device); - if (dev->iommu && dev->iommu->iommu_dev) + if (dev_has_iommu(dev)) iommu_deinit_device(dev); else dev->iommu_group =3D NULL; @@ -1218,6 +1227,12 @@ void iommu_group_remove_device(struct device *dev) } EXPORT_SYMBOL_GPL(iommu_group_remove_device); =20 +static struct device *iommu_group_first_dev(struct iommu_group *group) +{ + lockdep_assert_held(&group->mutex); + return list_first_entry(&group->devices, struct group_device, list)->dev; +} + /** * iommu_group_for_each_dev - iterate over each device in the group * @group: the group @@ -1745,9 +1760,7 @@ __iommu_group_alloc_default_domain(const struct bus_t= ype *bus, static struct iommu_domain * iommu_group_alloc_default_domain(struct iommu_group *group, int req_type) { - const struct bus_type *bus =3D - list_first_entry(&group->devices, struct group_device, list) - ->dev->bus; + const struct bus_type *bus =3D iommu_group_first_dev(group)->bus; struct iommu_domain *dom; =20 lockdep_assert_held(&group->mutex); @@ -1912,7 +1925,7 @@ bool device_iommu_capable(struct device *dev, enum io= mmu_cap cap) { const struct iommu_ops *ops; =20 - if (!dev->iommu || !dev->iommu->iommu_dev) + if (!dev_has_iommu(dev)) return false; =20 ops =3D dev_iommu_ops(dev); @@ -2903,8 +2916,8 @@ EXPORT_SYMBOL_GPL(iommu_fwspec_add_ids); */ int iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features f= eat) { - if (dev->iommu && dev->iommu->iommu_dev) { - const struct iommu_ops *ops =3D dev->iommu->iommu_dev->ops; + if (dev_has_iommu(dev)) { + const struct iommu_ops *ops =3D dev_iommu_ops(dev); =20 if (ops->dev_enable_feat) return ops->dev_enable_feat(dev, feat); @@ -2919,8 +2932,8 @@ EXPORT_SYMBOL_GPL(iommu_dev_enable_feature); */ int iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features = feat) { - if (dev->iommu && dev->iommu->iommu_dev) { - const struct iommu_ops *ops =3D dev->iommu->iommu_dev->ops; + if (dev_has_iommu(dev)) { + const struct iommu_ops *ops =3D dev_iommu_ops(dev); =20 if (ops->dev_disable_feat) return ops->dev_disable_feat(dev, feat); @@ -3190,21 +3203,18 @@ void iommu_device_unuse_default_domain(struct devic= e *dev) =20 static int __iommu_group_alloc_blocking_domain(struct iommu_group *group) { - struct group_device *dev =3D - list_first_entry(&group->devices, struct group_device, list); + struct device *dev =3D iommu_group_first_dev(group); =20 if (group->blocking_domain) return 0; =20 - group->blocking_domain =3D - __iommu_domain_alloc(dev->dev->bus, IOMMU_DOMAIN_BLOCKED); + group->blocking_domain =3D __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_BL= OCKED); if (!group->blocking_domain) { /* * For drivers that do not yet understand IOMMU_DOMAIN_BLOCKED * create an empty domain instead. */ - group->blocking_domain =3D __iommu_domain_alloc( - dev->dev->bus, IOMMU_DOMAIN_UNMANAGED); + group->blocking_domain =3D __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_U= NMANAGED); if (!group->blocking_domain) return -EINVAL; } --=20 2.39.2.101.g768bb238c484.dirty From nobody Thu Feb 12 07:59:46 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 8C63AEED619 for ; Fri, 15 Sep 2023 16:59:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235164AbjIOQ6o (ORCPT ); Fri, 15 Sep 2023 12:58:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59762 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234442AbjIOQ6b (ORCPT ); Fri, 15 Sep 2023 12:58:31 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 5B73119BC for ; Fri, 15 Sep 2023 09:58:26 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5C6AC12FC; Fri, 15 Sep 2023 09:59:03 -0700 (PDT) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 0BB753F5A1; Fri, 15 Sep 2023 09:58:24 -0700 (PDT) From: Robin Murphy To: joro@8bytes.org, will@kernel.org Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, jgg@nvidia.com, baolu.lu@linux.intel.com Subject: [PATCH v3 2/7] iommu: Decouple iommu_present() from bus ops Date: Fri, 15 Sep 2023 17:58:06 +0100 Message-Id: X-Mailer: git-send-email 2.39.2.101.g768bb238c484.dirty In-Reply-To: References: 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" Much as I'd like to remove iommu_present(), the final remaining users are proving stubbornly difficult to clean up, so kick that can down the road and just rework it to preserve the current behaviour without depending on bus ops. Reviewed-by: Lu Baolu Reviewed-by: Jason Gunthorpe Signed-off-by: Robin Murphy --- v3: Tweak to use the ops-based check rather than group-based, to properly match the existing behaviour --- drivers/iommu/iommu.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 4566d0001cd3..2f29ee9dea64 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -1907,9 +1907,24 @@ int bus_iommu_probe(const struct bus_type *bus) return 0; } =20 +static int __iommu_present(struct device *dev, void *unused) +{ + return dev_has_iommu(dev); +} + +/** + * iommu_present() - make platform-specific assumptions about an IOMMU + * @bus: bus to check + * + * Do not use this function. You want device_iommu_mapped() instead. + * + * Return: true if some IOMMU is present for some device on the given bus.= In + * general it may not be the only IOMMU, and it may not be for the device = you + * are ultimately interested in. + */ bool iommu_present(const struct bus_type *bus) { - return bus->iommu_ops !=3D NULL; + return bus_for_each_dev(bus, NULL, NULL, __iommu_present) > 0; } EXPORT_SYMBOL_GPL(iommu_present); =20 --=20 2.39.2.101.g768bb238c484.dirty From nobody Thu Feb 12 07:59:46 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 ABFCFEED61F for ; Fri, 15 Sep 2023 16:59:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235233AbjIOQ6p (ORCPT ); Fri, 15 Sep 2023 12:58:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37966 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234636AbjIOQ6d (ORCPT ); Fri, 15 Sep 2023 12:58:33 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 4B25319BC for ; Fri, 15 Sep 2023 09:58:28 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4CD391FB; Fri, 15 Sep 2023 09:59:05 -0700 (PDT) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id F037E3F5A1; Fri, 15 Sep 2023 09:58:26 -0700 (PDT) From: Robin Murphy To: joro@8bytes.org, will@kernel.org Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, jgg@nvidia.com, baolu.lu@linux.intel.com Subject: [PATCH v3 3/7] iommu: Validate that devices match domains Date: Fri, 15 Sep 2023 17:58:07 +0100 Message-Id: X-Mailer: git-send-email 2.39.2.101.g768bb238c484.dirty In-Reply-To: References: 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" Before we can allow drivers to coexist, we need to make sure that one driver's domain ops can't misinterpret another driver's dev_iommu_priv data. To that end, add a token to the domain so we can remember how it was allocated - for now this may as well be the device ops, since they still correlate 1:1 with drivers. We can trust ourselves for internal default domain attachment, so add the check where it covers both the external attach interfaces. Reviewed-by: Lu Baolu Reviewed-by: Jason Gunthorpe Signed-off-by: Robin Murphy --- drivers/iommu/iommu.c | 13 +++++++++---- include/linux/iommu.h | 1 + 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 2f29ee9dea64..f4cc91227b22 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -2000,26 +2000,28 @@ EXPORT_SYMBOL_GPL(iommu_set_fault_handler); static struct iommu_domain *__iommu_domain_alloc(const struct bus_type *bu= s, unsigned type) { + const struct iommu_ops *ops =3D bus ? bus->iommu_ops : NULL; struct iommu_domain *domain; unsigned int alloc_type =3D type & IOMMU_DOMAIN_ALLOC_FLAGS; =20 - if (bus =3D=3D NULL || bus->iommu_ops =3D=3D NULL) + if (!ops) return NULL; =20 - domain =3D bus->iommu_ops->domain_alloc(alloc_type); + domain =3D ops->domain_alloc(alloc_type); if (!domain) return NULL; =20 domain->type =3D type; + domain->owner =3D ops; /* * If not already set, assume all sizes by default; the driver * may override this later */ if (!domain->pgsize_bitmap) - domain->pgsize_bitmap =3D bus->iommu_ops->pgsize_bitmap; + domain->pgsize_bitmap =3D ops->pgsize_bitmap; =20 if (!domain->ops) - domain->ops =3D bus->iommu_ops->default_domain_ops; + domain->ops =3D ops->default_domain_ops; =20 if (iommu_is_dma_domain(domain) && iommu_get_dma_cookie(domain)) { iommu_domain_free(domain); @@ -2176,6 +2178,9 @@ static int __iommu_attach_group(struct iommu_domain *= domain, group->domain !=3D group->blocking_domain) return -EBUSY; =20 + if (dev_iommu_ops(iommu_group_first_dev(group)) !=3D domain->owner) + return -EINVAL; + return __iommu_group_set_domain(group, domain); } =20 diff --git a/include/linux/iommu.h b/include/linux/iommu.h index a249e10c8e9f..75ffcac199e3 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -95,6 +95,7 @@ struct iommu_domain_geometry { struct iommu_domain { unsigned type; const struct iommu_domain_ops *ops; + const struct iommu_ops *owner; /* Whose domain_alloc we came from */ unsigned long pgsize_bitmap; /* Bitmap of page sizes in use */ struct iommu_domain_geometry geometry; struct iommu_dma_cookie *iova_cookie; --=20 2.39.2.101.g768bb238c484.dirty From nobody Thu Feb 12 07:59:46 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 CD29AEED621 for ; Fri, 15 Sep 2023 16:59:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235291AbjIOQ6s (ORCPT ); Fri, 15 Sep 2023 12:58:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37980 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234662AbjIOQ6g (ORCPT ); Fri, 15 Sep 2023 12:58:36 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 386F819BC for ; Fri, 15 Sep 2023 09:58:30 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3C1FB139F; Fri, 15 Sep 2023 09:59:07 -0700 (PDT) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id DCAF13F5A1; Fri, 15 Sep 2023 09:58:28 -0700 (PDT) From: Robin Murphy To: joro@8bytes.org, will@kernel.org Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, jgg@nvidia.com, baolu.lu@linux.intel.com Subject: [PATCH v3 4/7] iommu: Switch __iommu_domain_alloc() to device ops Date: Fri, 15 Sep 2023 17:58:08 +0100 Message-Id: <404d8395cf4252c6fe6d98f317f3570127451778.1694693889.git.robin.murphy@arm.com> X-Mailer: git-send-email 2.39.2.101.g768bb238c484.dirty In-Reply-To: References: 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" In all the places we allocate default domains, we have (or can easily get hold of) a device from which to resolve the right IOMMU ops; only the public iommu_domain_alloc() interface actually depends on bus ops. Reworking the public API is a big enough mission in its own right, but in the meantime we can still decouple it from bus ops internally to move forward. Reviewed-by: Lu Baolu Signed-off-by: Robin Murphy --- v3: Make sure blocking domains are covered as well --- drivers/iommu/iommu.c | 50 +++++++++++++++++++++++++++++-------------- 1 file changed, 34 insertions(+), 16 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index f4cc91227b22..29ebb4b57df4 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -96,7 +96,7 @@ static const char * const iommu_group_resv_type_string[] = =3D { static int iommu_bus_notifier(struct notifier_block *nb, unsigned long action, void *data); static void iommu_release_device(struct device *dev); -static struct iommu_domain *__iommu_domain_alloc(const struct bus_type *bu= s, +static struct iommu_domain *__iommu_domain_alloc(struct device *dev, unsigned type); static int __iommu_attach_device(struct iommu_domain *domain, struct device *dev); @@ -1745,12 +1745,11 @@ static int iommu_get_def_domain_type(struct device = *dev) } =20 static struct iommu_domain * -__iommu_group_alloc_default_domain(const struct bus_type *bus, - struct iommu_group *group, int req_type) +__iommu_group_alloc_default_domain(struct iommu_group *group, int req_type) { if (group->default_domain && group->default_domain->type =3D=3D req_type) return group->default_domain; - return __iommu_domain_alloc(bus, req_type); + return __iommu_domain_alloc(iommu_group_first_dev(group), req_type); } =20 /* @@ -1760,23 +1759,22 @@ __iommu_group_alloc_default_domain(const struct bus= _type *bus, static struct iommu_domain * iommu_group_alloc_default_domain(struct iommu_group *group, int req_type) { - const struct bus_type *bus =3D iommu_group_first_dev(group)->bus; struct iommu_domain *dom; =20 lockdep_assert_held(&group->mutex); =20 if (req_type) - return __iommu_group_alloc_default_domain(bus, group, req_type); + return __iommu_group_alloc_default_domain(group, req_type); =20 /* The driver gave no guidance on what type to use, try the default */ - dom =3D __iommu_group_alloc_default_domain(bus, group, iommu_def_domain_t= ype); + dom =3D __iommu_group_alloc_default_domain(group, iommu_def_domain_type); if (dom) return dom; =20 /* Otherwise IDENTITY and DMA_FQ defaults will try DMA */ if (iommu_def_domain_type =3D=3D IOMMU_DOMAIN_DMA) return NULL; - dom =3D __iommu_group_alloc_default_domain(bus, group, IOMMU_DOMAIN_DMA); + dom =3D __iommu_group_alloc_default_domain(group, IOMMU_DOMAIN_DMA); if (!dom) return NULL; =20 @@ -1997,16 +1995,13 @@ void iommu_set_fault_handler(struct iommu_domain *d= omain, } EXPORT_SYMBOL_GPL(iommu_set_fault_handler); =20 -static struct iommu_domain *__iommu_domain_alloc(const struct bus_type *bu= s, +static struct iommu_domain *__iommu_domain_alloc(struct device *dev, unsigned type) { - const struct iommu_ops *ops =3D bus ? bus->iommu_ops : NULL; + const struct iommu_ops *ops =3D dev_iommu_ops(dev); struct iommu_domain *domain; unsigned int alloc_type =3D type & IOMMU_DOMAIN_ALLOC_FLAGS; =20 - if (!ops) - return NULL; - domain =3D ops->domain_alloc(alloc_type); if (!domain) return NULL; @@ -2030,9 +2025,28 @@ static struct iommu_domain *__iommu_domain_alloc(con= st struct bus_type *bus, return domain; } =20 +static int __iommu_domain_alloc_dev(struct device *dev, void *data) +{ + struct device **alloc_dev =3D data; + + if (!dev_has_iommu(dev)) + return 0; + + WARN_ONCE(*alloc_dev && dev_iommu_ops(dev) !=3D dev_iommu_ops(*alloc_dev), + "Multiple IOMMU drivers present, which the public IOMMU API can't full= y support yet. You may still need to disable one or more to get the expecte= d result here, sorry!\n"); + + *alloc_dev =3D dev; + return 0; +} + struct iommu_domain *iommu_domain_alloc(const struct bus_type *bus) { - return __iommu_domain_alloc(bus, IOMMU_DOMAIN_UNMANAGED); + struct device *dev =3D NULL; + + if (bus_for_each_dev(bus, NULL, &dev, __iommu_domain_alloc_dev)) + return NULL; + + return __iommu_domain_alloc(dev, IOMMU_DOMAIN_UNMANAGED); } EXPORT_SYMBOL_GPL(iommu_domain_alloc); =20 @@ -3228,13 +3242,17 @@ static int __iommu_group_alloc_blocking_domain(stru= ct iommu_group *group) if (group->blocking_domain) return 0; =20 - group->blocking_domain =3D __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_BL= OCKED); + /* noiommu groups should never be here */ + if (WARN_ON(!dev_has_iommu(dev))) + return -ENODEV; + + group->blocking_domain =3D __iommu_domain_alloc(dev, IOMMU_DOMAIN_BLOCKED= ); if (!group->blocking_domain) { /* * For drivers that do not yet understand IOMMU_DOMAIN_BLOCKED * create an empty domain instead. */ - group->blocking_domain =3D __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_U= NMANAGED); + group->blocking_domain =3D __iommu_domain_alloc(dev, IOMMU_DOMAIN_UNMANA= GED); if (!group->blocking_domain) return -EINVAL; } --=20 2.39.2.101.g768bb238c484.dirty From nobody Thu Feb 12 07:59:46 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 BD856EED61E for ; Fri, 15 Sep 2023 16:59:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235270AbjIOQ6q (ORCPT ); Fri, 15 Sep 2023 12:58:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37996 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234696AbjIOQ6g (ORCPT ); Fri, 15 Sep 2023 12:58:36 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 26757211E for ; Fri, 15 Sep 2023 09:58:32 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2A72CC15; Fri, 15 Sep 2023 09:59:09 -0700 (PDT) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id C535E3F5A1; Fri, 15 Sep 2023 09:58:30 -0700 (PDT) From: Robin Murphy To: joro@8bytes.org, will@kernel.org Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, jgg@nvidia.com, baolu.lu@linux.intel.com Subject: [PATCH v3 5/7] iommu/arm-smmu: Don't register fwnode for legacy binding Date: Fri, 15 Sep 2023 17:58:09 +0100 Message-Id: <59a39f152a344cdfd26ca9f802562fc14a449d38.1694693889.git.robin.murphy@arm.com> X-Mailer: git-send-email 2.39.2.101.g768bb238c484.dirty In-Reply-To: References: 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" When using the legacy binding we bypass the of_xlate mechanism, so avoid registering the instance fwnodes which act as keys for that. This will help __iommu_probe_device() to retrieve the registered ops the same way as for x86 etc. when no fwspec has previously been set up by of_xlate. Reviewed-by: Jason Gunthorpe Signed-off-by: Robin Murphy --- drivers/iommu/arm/arm-smmu/arm-smmu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-= smmu/arm-smmu.c index d6d1a2a55cc0..4b83a3adacd6 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c @@ -2161,7 +2161,8 @@ static int arm_smmu_device_probe(struct platform_devi= ce *pdev) return err; } =20 - err =3D iommu_device_register(&smmu->iommu, &arm_smmu_ops, dev); + err =3D iommu_device_register(&smmu->iommu, &arm_smmu_ops, + using_legacy_binding ? NULL : dev); if (err) { dev_err(dev, "Failed to register iommu\n"); iommu_device_sysfs_remove(&smmu->iommu); --=20 2.39.2.101.g768bb238c484.dirty From nobody Thu Feb 12 07:59:46 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 28055EED61A for ; Fri, 15 Sep 2023 16:59:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231224AbjIOQ7N (ORCPT ); Fri, 15 Sep 2023 12:59:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38010 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234759AbjIOQ6m (ORCPT ); Fri, 15 Sep 2023 12:58:42 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id B5D6C2126 for ; Fri, 15 Sep 2023 09:58:36 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B9FDF1FB; Fri, 15 Sep 2023 09:59:13 -0700 (PDT) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 0FA203F5A1; Fri, 15 Sep 2023 09:58:34 -0700 (PDT) From: Robin Murphy To: joro@8bytes.org, will@kernel.org Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, jgg@nvidia.com, baolu.lu@linux.intel.com, "Rafael J . Wysocki" , Christoph Hellwig , Greg Kroah-Hartman Subject: [PATCH v3 6/7] iommu: Retire bus ops Date: Fri, 15 Sep 2023 17:58:10 +0100 Message-Id: X-Mailer: git-send-email 2.39.2.101.g768bb238c484.dirty In-Reply-To: References: 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" With the rest of the API internals converted, it's time to finally tackle probe_device and how we bootstrap the per-device ops association to begin with. This ends up being disappointingly straightforward, since fwspec users are already doing it in order to find their of_xlate callback, and it works out that we can easily do the equivalent for other drivers too. Then shuffle the remaining awareness of iommu_ops into the couple of core headers that still need it, and breathe a sigh of relief. Ding dong the bus ops are gone! CC: Rafael J. Wysocki Acked-by: Christoph Hellwig Acked-by: Greg Kroah-Hartman Reviewed-by: Lu Baolu Reviewed-by: Jason Gunthorpe Signed-off-by: Robin Murphy --- drivers/iommu/iommu.c | 30 ++++++++++++++++++------------ include/acpi/acpi_bus.h | 2 ++ include/linux/device.h | 1 - include/linux/device/bus.h | 5 ----- include/linux/dma-map-ops.h | 1 + 5 files changed, 21 insertions(+), 18 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 29ebb4b57df4..d38c3023887a 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -149,7 +149,7 @@ struct iommu_group_attribute iommu_group_attr_##_name = =3D \ static LIST_HEAD(iommu_device_list); static DEFINE_SPINLOCK(iommu_device_lock); =20 -static struct bus_type * const iommu_buses[] =3D { +static const struct bus_type * const iommu_buses[] =3D { &platform_bus_type, #ifdef CONFIG_PCI &pci_bus_type, @@ -256,13 +256,6 @@ int iommu_device_register(struct iommu_device *iommu, /* We need to be able to take module references appropriately */ if (WARN_ON(is_module_address((unsigned long)ops) && !ops->owner)) return -EINVAL; - /* - * Temporarily enforce global restriction to a single driver. This was - * already the de-facto behaviour, since any possible combination of - * existing drivers would compete for at least the PCI or platform bus. - */ - if (iommu_buses[0]->iommu_ops && iommu_buses[0]->iommu_ops !=3D ops) - return -EBUSY; =20 iommu->ops =3D ops; if (hwdev) @@ -272,10 +265,8 @@ int iommu_device_register(struct iommu_device *iommu, list_add_tail(&iommu->list, &iommu_device_list); spin_unlock(&iommu_device_lock); =20 - for (int i =3D 0; i < ARRAY_SIZE(iommu_buses) && !err; i++) { - iommu_buses[i]->iommu_ops =3D ops; + for (int i =3D 0; i < ARRAY_SIZE(iommu_buses) && !err; i++) err =3D bus_iommu_probe(iommu_buses[i]); - } if (err) iommu_device_unregister(iommu); return err; @@ -490,12 +481,27 @@ static void iommu_deinit_device(struct device *dev) =20 static int __iommu_probe_device(struct device *dev, struct list_head *grou= p_list) { - const struct iommu_ops *ops =3D dev->bus->iommu_ops; + const struct iommu_ops *ops; + struct iommu_fwspec *fwspec; struct iommu_group *group; static DEFINE_MUTEX(iommu_probe_device_lock); struct group_device *gdev; int ret; =20 + /* + * For FDT-based systems and ACPI IORT/VIOT, drivers register IOMMU + * instances with non-NULL fwnodes, and client devices should have been + * identified with a fwspec by this point. Otherwise, we can currently + * assume that only one of Intel, AMD, s390, PAMU or legacy SMMUv2 can + * be present, and that any of their registered instances has suitable + * ops for probing, and thus cheekily co-opt the same mechanism. + */ + fwspec =3D dev_iommu_fwspec_get(dev); + if (fwspec && fwspec->ops) + ops =3D fwspec->ops; + else + ops =3D iommu_ops_from_fwnode(NULL); + if (!ops) return -ENODEV; /* diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index 254685085c82..13d959b3ba29 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -623,6 +623,8 @@ struct acpi_pci_root { =20 /* helper */ =20 +struct iommu_ops; + bool acpi_dma_supported(const struct acpi_device *adev); enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev); int acpi_iommu_fwspec_init(struct device *dev, u32 id, diff --git a/include/linux/device.h b/include/linux/device.h index 56d93a1ffb7b..b78e66f3b34a 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -42,7 +42,6 @@ struct class; struct subsys_private; struct device_node; struct fwnode_handle; -struct iommu_ops; struct iommu_group; struct dev_pin_info; struct dev_iommu; diff --git a/include/linux/device/bus.h b/include/linux/device/bus.h index ae10c4322754..e25aab08f873 100644 --- a/include/linux/device/bus.h +++ b/include/linux/device/bus.h @@ -62,9 +62,6 @@ struct fwnode_handle; * this bus. * @pm: Power management operations of this bus, callback the specific * device driver's pm-ops. - * @iommu_ops: IOMMU specific operations for this bus, used to attach IOM= MU - * driver implementations to a bus and allow the driver to do - * bus-specific setup * @need_parent_lock: When probing or removing a device on this bus, the * device core should lock the device's parent. * @@ -104,8 +101,6 @@ struct bus_type { =20 const struct dev_pm_ops *pm; =20 - const struct iommu_ops *iommu_ops; - bool need_parent_lock; }; =20 diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h index f2fc203fb8a1..a52e508d1869 100644 --- a/include/linux/dma-map-ops.h +++ b/include/linux/dma-map-ops.h @@ -11,6 +11,7 @@ #include =20 struct cma; +struct iommu_ops; =20 /* * Values for struct dma_map_ops.flags: --=20 2.39.2.101.g768bb238c484.dirty From nobody Thu Feb 12 07:59:46 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 37962EED619 for ; Fri, 15 Sep 2023 16:59:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234902AbjIOQ7O (ORCPT ); Fri, 15 Sep 2023 12:59:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49570 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235204AbjIOQ6p (ORCPT ); Fri, 15 Sep 2023 12:58:45 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 4CDE719BC for ; Fri, 15 Sep 2023 09:58:39 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4ED48C15; Fri, 15 Sep 2023 09:59:16 -0700 (PDT) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id F23EC3F5A1; Fri, 15 Sep 2023 09:58:37 -0700 (PDT) From: Robin Murphy To: joro@8bytes.org, will@kernel.org Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, jgg@nvidia.com, baolu.lu@linux.intel.com Subject: [PATCH v3 7/7] iommu: Clean up open-coded ownership checks Date: Fri, 15 Sep 2023 17:58:11 +0100 Message-Id: <05f95c41ec644440f2f375b1dc04c8254f667316.1694693889.git.robin.murphy@arm.com> X-Mailer: git-send-email 2.39.2.101.g768bb238c484.dirty In-Reply-To: References: 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" Some drivers already implement their own defence against the possibility of being given someone else's device. Since this is now taken care of by the core code (and via a slightly different path from the original fwspec-based idea), let's clean them up. Reviewed-by: Jason Gunthorpe Signed-off-by: Robin Murphy --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 3 --- drivers/iommu/arm/arm-smmu/arm-smmu.c | 9 +-------- drivers/iommu/arm/arm-smmu/qcom_iommu.c | 14 ++------------ drivers/iommu/mtk_iommu.c | 7 +------ drivers/iommu/mtk_iommu_v1.c | 3 --- drivers/iommu/sprd-iommu.c | 8 +------- drivers/iommu/virtio-iommu.c | 3 --- 7 files changed, 5 insertions(+), 42 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/ar= m/arm-smmu-v3/arm-smmu-v3.c index e82bf1c449a3..01ea307c7791 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -2653,9 +2653,6 @@ static struct iommu_device *arm_smmu_probe_device(str= uct device *dev) struct arm_smmu_master *master; struct iommu_fwspec *fwspec =3D dev_iommu_fwspec_get(dev); =20 - if (!fwspec || fwspec->ops !=3D &arm_smmu_ops) - return ERR_PTR(-ENODEV); - if (WARN_ON_ONCE(dev_iommu_priv_get(dev))) return ERR_PTR(-EBUSY); =20 diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-= smmu/arm-smmu.c index 4b83a3adacd6..4d09c0047892 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c @@ -1116,11 +1116,6 @@ static int arm_smmu_attach_dev(struct iommu_domain *= domain, struct device *dev) struct arm_smmu_device *smmu; int ret; =20 - if (!fwspec || fwspec->ops !=3D &arm_smmu_ops) { - dev_err(dev, "cannot attach to SMMU, is it on the same bus?\n"); - return -ENXIO; - } - /* * FIXME: The arch/arm DMA API code tries to attach devices to its own * domains between of_xlate() and probe_device() - we have no way to cope @@ -1357,10 +1352,8 @@ static struct iommu_device *arm_smmu_probe_device(st= ruct device *dev) fwspec =3D dev_iommu_fwspec_get(dev); if (ret) goto out_free; - } else if (fwspec && fwspec->ops =3D=3D &arm_smmu_ops) { - smmu =3D arm_smmu_get_by_fwnode(fwspec->iommu_fwnode); } else { - return ERR_PTR(-ENODEV); + smmu =3D arm_smmu_get_by_fwnode(fwspec->iommu_fwnode); } =20 ret =3D -EINVAL; diff --git a/drivers/iommu/arm/arm-smmu/qcom_iommu.c b/drivers/iommu/arm/ar= m-smmu/qcom_iommu.c index 775a3cbaff4e..b86fcd761ff7 100644 --- a/drivers/iommu/arm/arm-smmu/qcom_iommu.c +++ b/drivers/iommu/arm/arm-smmu/qcom_iommu.c @@ -79,16 +79,6 @@ static struct qcom_iommu_domain *to_qcom_iommu_domain(st= ruct iommu_domain *dom) =20 static const struct iommu_ops qcom_iommu_ops; =20 -static struct qcom_iommu_dev * to_iommu(struct device *dev) -{ - struct iommu_fwspec *fwspec =3D dev_iommu_fwspec_get(dev); - - if (!fwspec || fwspec->ops !=3D &qcom_iommu_ops) - return NULL; - - return dev_iommu_priv_get(dev); -} - static struct qcom_iommu_ctx * to_ctx(struct qcom_iommu_domain *d, unsigne= d asid) { struct qcom_iommu_dev *qcom_iommu =3D d->iommu; @@ -374,7 +364,7 @@ static void qcom_iommu_domain_free(struct iommu_domain = *domain) =20 static int qcom_iommu_attach_dev(struct iommu_domain *domain, struct devic= e *dev) { - struct qcom_iommu_dev *qcom_iommu =3D to_iommu(dev); + struct qcom_iommu_dev *qcom_iommu =3D dev_iommu_priv_get(dev); struct qcom_iommu_domain *qcom_domain =3D to_qcom_iommu_domain(domain); int ret; =20 @@ -499,7 +489,7 @@ static bool qcom_iommu_capable(struct device *dev, enum= iommu_cap cap) =20 static struct iommu_device *qcom_iommu_probe_device(struct device *dev) { - struct qcom_iommu_dev *qcom_iommu =3D to_iommu(dev); + struct qcom_iommu_dev *qcom_iommu =3D dev_iommu_priv_get(dev); struct device_link *link; =20 if (!qcom_iommu) diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index 640275873a27..dc292aeb6dbf 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -844,16 +844,11 @@ static phys_addr_t mtk_iommu_iova_to_phys(struct iomm= u_domain *domain, static struct iommu_device *mtk_iommu_probe_device(struct device *dev) { struct iommu_fwspec *fwspec =3D dev_iommu_fwspec_get(dev); - struct mtk_iommu_data *data; + struct mtk_iommu_data *data =3D dev_iommu_priv_get(dev); struct device_link *link; struct device *larbdev; unsigned int larbid, larbidx, i; =20 - if (!fwspec || fwspec->ops !=3D &mtk_iommu_ops) - return ERR_PTR(-ENODEV); /* Not a iommu client device */ - - data =3D dev_iommu_priv_get(dev); - if (!MTK_IOMMU_IS_TYPE(data->plat_data, MTK_IOMMU_TYPE_MM)) return &data->iommu; =20 diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c index 8a0a5e5d049f..2a764b73eb32 100644 --- a/drivers/iommu/mtk_iommu_v1.c +++ b/drivers/iommu/mtk_iommu_v1.c @@ -478,9 +478,6 @@ static struct iommu_device *mtk_iommu_v1_probe_device(s= truct device *dev) idx++; } =20 - if (!fwspec || fwspec->ops !=3D &mtk_iommu_v1_ops) - return ERR_PTR(-ENODEV); /* Not a iommu client device */ - data =3D dev_iommu_priv_get(dev); =20 /* Link the consumer device with the smi-larb device(supplier) */ diff --git a/drivers/iommu/sprd-iommu.c b/drivers/iommu/sprd-iommu.c index 2fa9afebd4f5..a69680fbb519 100644 --- a/drivers/iommu/sprd-iommu.c +++ b/drivers/iommu/sprd-iommu.c @@ -388,13 +388,7 @@ static phys_addr_t sprd_iommu_iova_to_phys(struct iomm= u_domain *domain, =20 static struct iommu_device *sprd_iommu_probe_device(struct device *dev) { - struct iommu_fwspec *fwspec =3D dev_iommu_fwspec_get(dev); - struct sprd_iommu_device *sdev; - - if (!fwspec || fwspec->ops !=3D &sprd_iommu_ops) - return ERR_PTR(-ENODEV); - - sdev =3D dev_iommu_priv_get(dev); + struct sprd_iommu_device *sdev =3D dev_iommu_priv_get(dev); =20 return &sdev->iommu; } diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index 17dcd826f5c2..bb2e795a80d0 100644 --- a/drivers/iommu/virtio-iommu.c +++ b/drivers/iommu/virtio-iommu.c @@ -969,9 +969,6 @@ static struct iommu_device *viommu_probe_device(struct = device *dev) struct viommu_dev *viommu =3D NULL; struct iommu_fwspec *fwspec =3D dev_iommu_fwspec_get(dev); =20 - if (!fwspec || fwspec->ops !=3D &viommu_ops) - return ERR_PTR(-ENODEV); - viommu =3D viommu_get_by_fwnode(fwspec->iommu_fwnode); if (!viommu) return ERR_PTR(-ENODEV); --=20 2.39.2.101.g768bb238c484.dirty