From patchwork Fri Sep 15 16:58:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Robin Murphy X-Patchwork-Id: 13387273 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7D0BEEED61A for ; Fri, 15 Sep 2023 16:59:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=wm4pIG+X8RZLIIVymasa3YFq6gmr32HM6GjgkJqTSWc=; b=CUBiuMgRsmv1xK Dx9LfQK03jIhKFgbP6Pdf5KQ0IlVvLwuz3u48NAiBNaefR7ba77/2LieJOpnbbinfOq8cRQh+Bb7Q zBCWfNwBnLLEeWIC/2es77ALCHlaGT19uHE4V2yvi9ePMa8xBjhaCyg3Mb+qUIQie2HW46krfPZVs XfXlOgXD2LNOOhHHILoC31XbLcXCo5ESXx9QhCKFye43ot/Xgvo+Kt4/1G4QUaIAvfHmrHg7AVNP+ 245CDZLb+ZjueX+8TxDQeWY9HcTyIrnHEhvcR1uCPLZeT8EkfSxAeY6XJK1jceY44zGaCACGmP7Pi zdeymBprbj4ooXbIHa5w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qhC9Z-00B5aA-1C; Fri, 15 Sep 2023 16:58:49 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qhC9P-00B5Un-0P for linux-arm-kernel@lists.infradead.org; Fri, 15 Sep 2023 16:58:40 +0000 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230915_095839_258621_4137F550 X-CRM114-Status: GOOD ( 22.43 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 = \ static LIST_HEAD(iommu_device_list); static DEFINE_SPINLOCK(iommu_device_lock); -static struct bus_type * const iommu_buses[] = { +static const struct bus_type * const iommu_buses[] = { &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 != ops) - return -EBUSY; iommu->ops = 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); - for (int i = 0; i < ARRAY_SIZE(iommu_buses) && !err; i++) { - iommu_buses[i]->iommu_ops = ops; + for (int i = 0; i < ARRAY_SIZE(iommu_buses) && !err; i++) err = 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) static int __iommu_probe_device(struct device *dev, struct list_head *group_list) { - const struct iommu_ops *ops = 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; + /* + * 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 = dev_iommu_fwspec_get(dev); + if (fwspec && fwspec->ops) + ops = fwspec->ops; + else + ops = 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 { /* helper */ +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 IOMMU - * 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 { const struct dev_pm_ops *pm; - const struct iommu_ops *iommu_ops; - bool need_parent_lock; }; 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 struct cma; +struct iommu_ops; /* * Values for struct dma_map_ops.flags: