From mboxrd@z Thu Jan 1 00:00:00 1970 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 6C5D8C43219 for ; Thu, 14 Apr 2022 12:43:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243492AbiDNMpY (ORCPT ); Thu, 14 Apr 2022 08:45:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51984 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243472AbiDNMpR (ORCPT ); Thu, 14 Apr 2022 08:45:17 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 622DC85666 for ; Thu, 14 Apr 2022 05:42:52 -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 25A44139F; Thu, 14 Apr 2022 05:42:52 -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 2B9943F70D; Thu, 14 Apr 2022 05:42:50 -0700 (PDT) From: Robin Murphy To: joro@8bytes.org, will@kernel.org Cc: iommu@lists.linux-foundation.org, sven@svenpeter.dev, robdclark@gmail.com, m.szyprowski@samsung.com, baolu.lu@linux.intel.com, yong.wu@mediatek.com, mjrosato@linux.ibm.com, gerald.schaefer@linux.ibm.com, zhang.lyra@gmail.com, thierry.reding@gmail.com, vdumpa@nvidia.com, jean-philippe@linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH 02/13] iommu: Move bus setup to IOMMU device registration Date: Thu, 14 Apr 2022 13:42:31 +0100 Message-Id: X-Mailer: git-send-email 2.28.0.dirty In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Move the bus setup to iommu_device_register(). This should allow bus_iommu_probe() to be correctly replayed for multiple IOMMU instances, and leaves bus_set_iommu() as a glorfied no-op to be cleaned up next. Note that although the handling of errors from bus_iommu_probe() looks inadequate, it is merely preserving the well-established existing behaviour. This could be improved in future - probably combined with equivalent cleanup for iommu_device_unregister() - but that isn't a priority right now. Signed-off-by: Robin Murphy --- drivers/iommu/iommu.c | 50 ++++++++++++++++++++++--------------------- 1 file changed, 26 insertions(+), 24 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 13e1a8bd5435..51205c33c426 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -175,6 +175,14 @@ static int __init iommu_subsys_init(void) } subsys_initcall(iommu_subsys_init); +static int remove_iommu_group(struct device *dev, void *data) +{ + if (dev->iommu && dev->iommu->iommu_dev == data) + iommu_release_device(dev); + + return 0; +} + /** * iommu_device_register() - Register an IOMMU hardware instance * @iommu: IOMMU handle for the instance @@ -197,6 +205,22 @@ int iommu_device_register(struct iommu_device *iommu, spin_lock(&iommu_device_lock); list_add_tail(&iommu->list, &iommu_device_list); spin_unlock(&iommu_device_lock); + + for (int i = 0; i < ARRAY_SIZE(iommu_buses); i++) { + struct bus_type *bus = iommu_buses[i]; + const struct iommu_ops *bus_ops = bus->iommu_ops; + int err; + + WARN_ON(bus_ops && bus_ops != ops); + bus->iommu_ops = ops; + err = bus_iommu_probe(bus); + if (err) { + bus_for_each_dev(bus, NULL, iommu, remove_iommu_group); + bus->iommu_ops = bus_ops; + return err; + } + } + return 0; } EXPORT_SYMBOL_GPL(iommu_device_register); @@ -1654,13 +1678,6 @@ static int probe_iommu_group(struct device *dev, void *data) return ret; } -static int remove_iommu_group(struct device *dev, void *data) -{ - iommu_release_device(dev); - - return 0; -} - static int iommu_bus_notifier(struct notifier_block *nb, unsigned long action, void *data) { @@ -1883,27 +1900,12 @@ static int iommu_bus_init(struct bus_type *bus) */ int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops) { - int err; - - if (ops == NULL) { - bus->iommu_ops = NULL; - return 0; - } - - if (bus->iommu_ops != NULL) + if (bus->iommu_ops && ops && bus->iommu_ops != ops) return -EBUSY; bus->iommu_ops = ops; - /* Do IOMMU specific setup for this bus-type */ - err = bus_iommu_probe(bus); - if (err) { - /* Clean up */ - bus_for_each_dev(bus, NULL, NULL, remove_iommu_group); - bus->iommu_ops = NULL; - } - - return err; + return 0; } EXPORT_SYMBOL_GPL(bus_set_iommu); -- 2.28.0.dirty