From patchwork Thu Jan 6 02:20:46 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Baolu Lu X-Patchwork-Id: 12705009 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 BDDFFC433F5 for ; Thu, 6 Jan 2022 02:21:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344690AbiAFCV6 (ORCPT ); Wed, 5 Jan 2022 21:21:58 -0500 Received: from mga06.intel.com ([134.134.136.31]:40628 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231945AbiAFCV4 (ORCPT ); Wed, 5 Jan 2022 21:21:56 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1641435716; x=1672971716; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=xKGR4J0OSP6uicbqMFdEjKsyZ291es72vzJYC31FqCM=; b=UkzgLYhy0TijKNKyTDtiI2dE0qGRgt5YTi76pCMYmUqIzW+qDjzRpAUV hCNCSs6aL/rBBQsP/saXwlPy5qunFDVGNGQ6apI3nlXifovcqBi2PqlGg a2kuXWp7lMjo78gn9VeURfIFNIwHIlQnpb+vMaS5Z7VPPVE97LBp4XxRV xEGNTZklolXVEnlzn7M0z4qZXTavfycOu0pI0rX/QgNSW6IXdhhDWEOjN z8E4w7qAnJxYyzouByw8FXuNvMbWfwh4TqVNX8O8uLCBj+Hc7CsIkl+7i 37aIQtT7YeB99vG7ZRMnlmKRuhzTNFOvuHGt9xC6yISXLTHHytWhMwqpI w==; X-IronPort-AV: E=McAfee;i="6200,9189,10217"; a="303325586" X-IronPort-AV: E=Sophos;i="5.88,265,1635231600"; d="scan'208";a="303325586" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jan 2022 18:21:56 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,265,1635231600"; d="scan'208";a="526794284" Received: from allen-box.sh.intel.com ([10.239.159.118]) by orsmga008.jf.intel.com with ESMTP; 05 Jan 2022 18:21:49 -0800 From: Lu Baolu To: Joerg Roedel , Alex Williamson , Robin Murphy , Jason Gunthorpe , Christoph Hellwig , Kevin Tian , Ashok Raj Cc: Greg Kroah-Hartman , Bjorn Helgaas , Will Deacon , Dan Williams , rafael@kernel.org, Diana Craciun , Cornelia Huck , Eric Auger , Liu Yi L , Jacob jun Pan , Chaitanya Kulkarni , Stuart Yoder , Laurentiu Tudor , Thierry Reding , David Airlie , Daniel Vetter , Jonathan Hunter , Li Yang , Dmitry Osipenko , iommu@lists.linux-foundation.org, linux-pci@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Lu Baolu Subject: [PATCH v1 1/8] iommu: Add iommu_group_replace_domain() Date: Thu, 6 Jan 2022 10:20:46 +0800 Message-Id: <20220106022053.2406748-2-baolu.lu@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220106022053.2406748-1-baolu.lu@linux.intel.com> References: <20220106022053.2406748-1-baolu.lu@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Expose an interface to replace the domain of an iommu group for frameworks like vfio which claims the ownership of the whole iommu group. Signed-off-by: Lu Baolu --- include/linux/iommu.h | 10 ++++++++++ drivers/iommu/iommu.c | 37 +++++++++++++++++++++++++++++++++++++ 2 files changed, 47 insertions(+) diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 408a6d2b3034..66ebce3d1e11 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -677,6 +677,9 @@ void iommu_device_unuse_dma_api(struct device *dev); int iommu_group_set_dma_owner(struct iommu_group *group, void *owner); void iommu_group_release_dma_owner(struct iommu_group *group); bool iommu_group_dma_owner_claimed(struct iommu_group *group); +int iommu_group_replace_domain(struct iommu_group *group, + struct iommu_domain *old, + struct iommu_domain *new); #else /* CONFIG_IOMMU_API */ @@ -1090,6 +1093,13 @@ static inline bool iommu_group_dma_owner_claimed(struct iommu_group *group) { return false; } + +static inline int +iommu_group_replace_domain(struct iommu_group *group, struct iommu_domain *old, + struct iommu_domain *new) +{ + return -ENODEV; +} #endif /* CONFIG_IOMMU_API */ /** diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 72a95dea688e..ab8ab95969f5 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -3431,3 +3431,40 @@ bool iommu_group_dma_owner_claimed(struct iommu_group *group) return user; } EXPORT_SYMBOL_GPL(iommu_group_dma_owner_claimed); + +/** + * iommu_group_replace_domain() - Replace group's domain + * @group: The group. + * @old: The previous attached domain. NULL for none. + * @new: The new domain about to be attached. + * + * This is to support backward compatibility for vfio which manages the dma + * ownership in iommu_group level. + */ +int iommu_group_replace_domain(struct iommu_group *group, + struct iommu_domain *old, + struct iommu_domain *new) +{ + int ret = 0; + + mutex_lock(&group->mutex); + if (!group->owner || group->domain != old) { + ret = -EPERM; + goto unlock_out; + } + + if (old) + __iommu_detach_group(old, group); + + if (new) { + ret = __iommu_attach_group(new, group); + if (ret && old) + __iommu_attach_group(old, group); + } + +unlock_out: + mutex_unlock(&group->mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(iommu_group_replace_domain);