From patchwork Thu Sep 12 13:12:46 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yi Liu X-Patchwork-Id: 828039 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.13]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DB5911A76D7 for ; Thu, 12 Sep 2024 13:12:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.13 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726146781; cv=none; b=u56FY6+2uSi0RXYvycfqd9q8dYNhjtanRldTJNYaPmXmAGbvqph82FmqoLuY9BLd0g7MqKWPD+nfMDJImyA307EWNoMta5zEKqJ14w5MF3i4BmgSR5fPmdGBJyKjXABspNOhFW4QFIIWkEKRZ7fFCwTX+edtAIkVn0/g6nb1Ol8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726146781; c=relaxed/simple; bh=0XxKBaycudG+spAOHgQrx0ct4g0+tJZYEtf66Xv1DFc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=K0tdhleTugDYk6QIohLwCH8UrGJJwqIeHljvZvgb7UeXF+fthiMloRnmkamnNMjhPrFsC3+VchQDqwz7f4ec+sMaNuIoiC3ZWR1YkhroVHMkNHhlMlNMiMngazDq8UUyreU1Wg5IkzFq6Ye2ecBMSMUPWcSbhej5PBGmcdRLy04= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=mKgekAsa; arc=none smtp.client-ip=192.198.163.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="mKgekAsa" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1726146779; x=1757682779; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=0XxKBaycudG+spAOHgQrx0ct4g0+tJZYEtf66Xv1DFc=; b=mKgekAsaLd9U94cS6UWDIN15+6m2ChYW99Dw4KcZLjTXqFHIXh8/hJ7P EKQGF0JRoIlDCrqB+fZsE7R1LoGPxVfepRFrLdUgEvPVmirvte2lCUY6N YNRY1HahUyGrH2lWK/UcBAnhM4bs9QSx4WRv6NhlEL7JQmljfSHNEKzpH 6CzDoxYpHjYR862rib06+k6TxXAvCA6quIHOC0o+HoATE1ksqBvX4D9Pm Y52fh/WPuXZy6ug/5aTdTypc8C98PN+NyCLHgjKG5xlwLpCCAK2aie7kl ANzRjQkFWRQuBALTWYJmVghX0D8UtP6YrRfwOZ5aRRNlDf0DFl3mXah0y w==; X-CSE-ConnectionGUID: K5sEXte9RiqJkrgN6xsueA== X-CSE-MsgGUID: cbfZeGSSRGWG/CTzMPsJDA== X-IronPort-AV: E=McAfee;i="6700,10204,11192"; a="27911202" X-IronPort-AV: E=Sophos;i="6.10,223,1719903600"; d="scan'208";a="27911202" Received: from orviesa006.jf.intel.com ([10.64.159.146]) by fmvoesa107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Sep 2024 06:12:57 -0700 X-CSE-ConnectionGUID: 8LM3Ao2LT3CR5aFJdHc1aw== X-CSE-MsgGUID: yH/YYeBNRfyVFuK1Ro4NeA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,223,1719903600"; d="scan'208";a="67996540" Received: from 984fee00a4c6.jf.intel.com ([10.165.58.231]) by orviesa006.jf.intel.com with ESMTP; 12 Sep 2024 06:12:57 -0700 From: Yi Liu To: joro@8bytes.org, jgg@nvidia.com, kevin.tian@intel.com, baolu.lu@linux.intel.com Cc: alex.williamson@redhat.com, eric.auger@redhat.com, nicolinc@nvidia.com, chao.p.peng@linux.intel.com, yi.l.liu@intel.com, iommu@lists.linux.dev, zhenzhong.duan@intel.com, linux-kselftest@vger.kernel.org, vasant.hegde@amd.com Subject: [PATCH v4 01/10] iommu: Introduce a replace API for device pasid Date: Thu, 12 Sep 2024 06:12:46 -0700 Message-Id: <20240912131255.13305-2-yi.l.liu@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240912131255.13305-1-yi.l.liu@intel.com> References: <20240912131255.13305-1-yi.l.liu@intel.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Provide a high-level API to allow replacements of one domain with another for specific pasid of a device. This is similar to iommu_group_replace_domain() and it is expected to be used only by IOMMUFD. Co-developed-by: Lu Baolu Signed-off-by: Lu Baolu Signed-off-by: Yi Liu --- drivers/iommu/iommu-priv.h | 4 ++ drivers/iommu/iommu.c | 90 ++++++++++++++++++++++++++++++++++++-- 2 files changed, 90 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/iommu-priv.h b/drivers/iommu/iommu-priv.h index de5b54eaa8bf..90b367de267e 100644 --- a/drivers/iommu/iommu-priv.h +++ b/drivers/iommu/iommu-priv.h @@ -27,6 +27,10 @@ static inline const struct iommu_ops *iommu_fwspec_ops(struct iommu_fwspec *fwsp int iommu_group_replace_domain(struct iommu_group *group, struct iommu_domain *new_domain); +int iommu_replace_device_pasid(struct iommu_domain *domain, + struct device *dev, ioasid_t pasid, + struct iommu_attach_handle *handle); + int iommu_device_register_bus(struct iommu_device *iommu, const struct iommu_ops *ops, const struct bus_type *bus, diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index b6b44b184004..066f659018a5 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -3347,14 +3347,15 @@ static void iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid, } static int __iommu_set_group_pasid(struct iommu_domain *domain, - struct iommu_group *group, ioasid_t pasid) + struct iommu_group *group, ioasid_t pasid, + struct iommu_domain *old) { struct group_device *device, *last_gdev; int ret; for_each_group_device(group, device) { ret = domain->ops->set_dev_pasid(domain, device->dev, - pasid, NULL); + pasid, old); if (ret) goto err_revert; } @@ -3366,7 +3367,20 @@ static int __iommu_set_group_pasid(struct iommu_domain *domain, for_each_group_device(group, device) { if (device == last_gdev) break; - iommu_remove_dev_pasid(device->dev, pasid, domain); + /* If no old domain, undo the succeeded devices/pasid */ + if (!old) { + iommu_remove_dev_pasid(device->dev, pasid, domain); + continue; + } + + /* + * Rollback the succeeded devices/pasid to the old domain. + * And it is a driver bug to fail attaching with a previously + * good domain. + */ + if (WARN_ON(old->ops->set_dev_pasid(old, device->dev, + pasid, domain))) + iommu_remove_dev_pasid(device->dev, pasid, domain); } return ret; } @@ -3425,7 +3439,7 @@ int iommu_attach_device_pasid(struct iommu_domain *domain, if (ret) goto out_unlock; - ret = __iommu_set_group_pasid(domain, group, pasid); + ret = __iommu_set_group_pasid(domain, group, pasid, NULL); if (ret) xa_erase(&group->pasid_array, pasid); out_unlock: @@ -3434,6 +3448,74 @@ int iommu_attach_device_pasid(struct iommu_domain *domain, } EXPORT_SYMBOL_GPL(iommu_attach_device_pasid); +/** + * iommu_replace_device_pasid - Replace the domain that a pasid is attached to + * @domain: the new iommu domain + * @dev: the attached device. + * @pasid: the pasid of the device. + * @handle: the attach handle. + * + * This API allows the pasid to switch domains. Return 0 on success, or an + * error. The pasid will keep the old configuration if replacement failed. + * This is supposed to be used by iommufd, and iommufd can guarantee that + * both iommu_attach_device_pasid() and iommu_replace_device_pasid() would + * pass in a valid @handle. + */ +int iommu_replace_device_pasid(struct iommu_domain *domain, + struct device *dev, ioasid_t pasid, + struct iommu_attach_handle *handle) +{ + /* Caller must be a probed driver on dev */ + struct iommu_group *group = dev->iommu_group; + struct iommu_attach_handle *curr; + int ret; + + if (!domain->ops->set_dev_pasid) + return -EOPNOTSUPP; + + if (!group) + return -ENODEV; + + if (!dev_has_iommu(dev) || dev_iommu_ops(dev) != domain->owner || + pasid == IOMMU_NO_PASID || !handle) + return -EINVAL; + + handle->domain = domain; + + mutex_lock(&group->mutex); + /* + * The iommu_attach_handle of the pasid becomes inconsistent with the + * actual handle per the below operation. The concurrent PRI path will + * deliver the PRQs per the new handle, this does not have a function + * impact. The PRI path would eventually become consistent when the + * replacement is done. + */ + curr = (struct iommu_attach_handle *)xa_store(&group->pasid_array, + pasid, handle, + GFP_KERNEL); + if (!curr) { + xa_erase(&group->pasid_array, pasid); + ret = -EINVAL; + goto out_unlock; + } + + ret = xa_err(curr); + if (ret) + goto out_unlock; + + if (curr->domain == domain) + goto out_unlock; + + ret = __iommu_set_group_pasid(domain, group, pasid, curr->domain); + if (ret) + WARN_ON(handle != xa_store(&group->pasid_array, pasid, + curr, GFP_KERNEL)); +out_unlock: + mutex_unlock(&group->mutex); + return ret; +} +EXPORT_SYMBOL_NS_GPL(iommu_replace_device_pasid, IOMMUFD_INTERNAL); + /* * iommu_detach_device_pasid() - Detach the domain from pasid of device * @domain: the iommu domain.