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 X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D2350C432C2 for ; Wed, 25 Sep 2019 13:23:16 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B29AF21D7C for ; Wed, 25 Sep 2019 13:23:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B29AF21D7C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id F340CE2B; Wed, 25 Sep 2019 13:23:13 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id E1E57AF0 for ; Wed, 25 Sep 2019 13:23:12 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 317D98C0 for ; Wed, 25 Sep 2019 13:23:04 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id D1FFE4D9; Wed, 25 Sep 2019 15:23:01 +0200 (CEST) From: Joerg Roedel To: iommu@lists.linux-foundation.org, Joerg Roedel Subject: [PATCH 3/6] iommu/amd: Take domain->lock for complete attach/detach path Date: Wed, 25 Sep 2019 15:22:57 +0200 Message-Id: <20190925132300.3038-4-joro@8bytes.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190925132300.3038-1-joro@8bytes.org> References: <20190925132300.3038-1-joro@8bytes.org> Cc: Filippo Sironi , jroedel@suse.de X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org From: Joerg Roedel The code-paths before __attach_device() and __detach_device() are called also access and modify domain state, so take the domain lock there too. This allows to get rid of the __detach_device() function. Fixes: 92d420ec028d ("iommu/amd: Relax locking in dma_ops path") Signed-off-by: Joerg Roedel --- drivers/iommu/amd_iommu.c | 65 ++++++++++++++++----------------------- 1 file changed, 26 insertions(+), 39 deletions(-) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 37a9c04fc728..2919168577ff 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -2079,27 +2079,13 @@ static void do_detach(struct iommu_dev_data *dev_data) static int __attach_device(struct iommu_dev_data *dev_data, struct protection_domain *domain) { - unsigned long flags; - int ret; - - /* lock domain */ - spin_lock_irqsave(&domain->lock, flags); - - ret = -EBUSY; if (dev_data->domain != NULL) - goto out_unlock; + return -EBUSY; /* Attach alias group root */ do_attach(dev_data, domain); - ret = 0; - -out_unlock: - - /* ready */ - spin_unlock_irqrestore(&domain->lock, flags); - - return ret; + return 0; } @@ -2181,8 +2167,11 @@ static int attach_device(struct device *dev, { struct pci_dev *pdev; struct iommu_dev_data *dev_data; + unsigned long flags; int ret; + spin_lock_irqsave(&domain->lock, flags); + dev_data = get_dev_data(dev); if (!dev_is_pci(dev)) @@ -2190,12 +2179,13 @@ static int attach_device(struct device *dev, pdev = to_pci_dev(dev); if (domain->flags & PD_IOMMUV2_MASK) { + ret = -EINVAL; if (!dev_data->passthrough) - return -EINVAL; + goto out; if (dev_data->iommu_v2) { if (pdev_iommuv2_enable(pdev) != 0) - return -EINVAL; + goto out; dev_data->ats.enabled = true; dev_data->ats.qdep = pci_ats_queue_depth(pdev); @@ -2219,24 +2209,10 @@ static int attach_device(struct device *dev, domain_flush_complete(domain); - return ret; -} - -/* - * Removes a device from a protection domain (unlocked) - */ -static void __detach_device(struct iommu_dev_data *dev_data) -{ - struct protection_domain *domain; - unsigned long flags; - - domain = dev_data->domain; - - spin_lock_irqsave(&domain->lock, flags); - - do_detach(dev_data); - +out: spin_unlock_irqrestore(&domain->lock, flags); + + return ret; } /* @@ -2246,10 +2222,13 @@ static void detach_device(struct device *dev) { struct protection_domain *domain; struct iommu_dev_data *dev_data; + unsigned long flags; dev_data = get_dev_data(dev); domain = dev_data->domain; + spin_lock_irqsave(&domain->lock, flags); + /* * First check if the device is still attached. It might already * be detached from its domain because the generic @@ -2257,12 +2236,12 @@ static void detach_device(struct device *dev) * our alias handling. */ if (WARN_ON(!dev_data->domain)) - return; + goto out; - __detach_device(dev_data); + do_detach(dev_data); if (!dev_is_pci(dev)) - return; + goto out; if (domain->flags & PD_IOMMUV2_MASK && dev_data->iommu_v2) pdev_iommuv2_disable(to_pci_dev(dev)); @@ -2270,6 +2249,9 @@ static void detach_device(struct device *dev) pci_disable_ats(to_pci_dev(dev)); dev_data->ats.enabled = false; + +out: + spin_unlock_irqrestore(&domain->lock, flags); } static int amd_iommu_add_device(struct device *dev) @@ -2904,13 +2886,18 @@ int __init amd_iommu_init_dma_ops(void) static void cleanup_domain(struct protection_domain *domain) { struct iommu_dev_data *entry; + unsigned long flags; + + spin_lock_irqsave(&domain->lock, flags); while (!list_empty(&domain->dev_list)) { entry = list_first_entry(&domain->dev_list, struct iommu_dev_data, list); BUG_ON(!entry->domain); - __detach_device(entry); + do_detach(entry); } + + spin_unlock_irqrestore(&domain->lock, flags); } static void protection_domain_free(struct protection_domain *domain) -- 2.17.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu