From patchwork Fri Jun 28 09:05:51 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yi Liu X-Patchwork-Id: 808772 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.12]) (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 B260315099D; Fri, 28 Jun 2024 09:06:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.12 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719565563; cv=none; b=p/YkjzuEnTFj6tccEr0rdecMdBhxe2lXAaPwilHywJ0mB7Tao7pVHim93WHhJ5sp/AwSZVpYRM1MjwdxDVXzZz6xNn+8Xilt3ZVNV9/rlR/jlwFsS0Q6qPVWMuxnuFSly3fLiSmoCDzjoeeEsaO6VrqnKvBqmxgBML8Yesy/yyg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719565563; c=relaxed/simple; bh=CwiYoVY+4opnvOlWCx/nZGteoxnrqoLWq2IwhViW33I=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Xy/7YihFheaoJmcDCBP6iQBD3cQz2RFMwFxkyy5W1xtYZyUUBe694sUecFnZEJGkdj9/ztCVp9XZ6Y4tPvATs1EHcB+ZGAh6ChXxo9hqPDyjxWE1jY/3Ip4GfJTXBgFfhv0TIppVT7GjMlq+O4l1nYEKupS7GW7H13MKB7RqZd4= 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=PmlGRuHL; arc=none smtp.client-ip=192.198.163.12 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="PmlGRuHL" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1719565561; x=1751101561; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=CwiYoVY+4opnvOlWCx/nZGteoxnrqoLWq2IwhViW33I=; b=PmlGRuHLT4tptk6YygSk9s3gsmtPjVJbZ9/KXbojohncp/YFm8X0lYH0 xB/riquFqEKMayBCZFsTdRy0/OlwQIUzvxNiHwO9lb03youSLPJhfMeSJ 7q1oT5ZyspHYv1uShcfdGLJiByNGdGLqYP+V4aI/qdcMa2feWjJnwX8u9 iy22QvObamrR5Ubh1nLenMIR8tl2jZ7xtrO4W7ZU+/yoltGHTUs8DRFel 2+Pl+4H9Vm9FwlB8csYxemtMoRGpY/GJNdE5fRIbVYDuXjeigY2kNgfoJ i0vwMvFI6OkgPvyI8Vhdh/9fXmZiQjV+WJ6BCLVNGfW+gLFlxjhISyz9h g==; X-CSE-ConnectionGUID: Qs4WTClTSfaumETZptxg3g== X-CSE-MsgGUID: uEL4OMmwQVyEccdOyRJasg== X-IronPort-AV: E=McAfee;i="6700,10204,11116"; a="20613669" X-IronPort-AV: E=Sophos;i="6.09,168,1716274800"; d="scan'208";a="20613669" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by fmvoesa106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Jun 2024 02:06:00 -0700 X-CSE-ConnectionGUID: fdKEQNbZTi6Xe6oljT2kLg== X-CSE-MsgGUID: aJ8+1hlQTJOOVEucDuUvPQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.09,168,1716274800"; d="scan'208";a="44517042" Received: from 984fee00a4c6.jf.intel.com ([10.165.58.231]) by fmviesa006.fm.intel.com with ESMTP; 28 Jun 2024 02:06:00 -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, robin.murphy@arm.com, eric.auger@redhat.com, nicolinc@nvidia.com, kvm@vger.kernel.org, chao.p.peng@linux.intel.com, yi.l.liu@intel.com, iommu@lists.linux.dev, zhenzhong.duan@intel.com, linux-kselftest@vger.kernel.org Subject: [PATCH v3 1/7] iommu: Introduce a replace API for device pasid Date: Fri, 28 Jun 2024 02:05:51 -0700 Message-Id: <20240628090557.50898-2-yi.l.liu@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240628090557.50898-1-yi.l.liu@intel.com> References: <20240628090557.50898-1-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 | 3 ++ drivers/iommu/iommu.c | 80 ++++++++++++++++++++++++++++++++++++-- 2 files changed, 79 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/iommu-priv.h b/drivers/iommu/iommu-priv.h index 5f731d994803..0949c02cee93 100644 --- a/drivers/iommu/iommu-priv.h +++ b/drivers/iommu/iommu-priv.h @@ -20,6 +20,9 @@ static inline const struct iommu_ops *dev_iommu_ops(struct device *dev) 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); + 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 b3a1dabed2dd..2d64582b7c43 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -3268,14 +3268,15 @@ bool iommu_group_dma_owner_claimed(struct iommu_group *group) EXPORT_SYMBOL_GPL(iommu_group_dma_owner_claimed); 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; } @@ -3289,7 +3290,20 @@ static int __iommu_set_group_pasid(struct iommu_domain *domain, if (device == last_gdev) break; - ops->remove_dev_pasid(device->dev, pasid, domain); + /* If no old domain, undo the succeeded devices/pasid */ + if (!old) { + ops->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))) + ops->remove_dev_pasid(device->dev, pasid, domain); } return ret; } @@ -3348,7 +3362,7 @@ int iommu_attach_device_pasid(struct iommu_domain *domain, 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: @@ -3357,6 +3371,64 @@ 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. + * + * 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. + */ +int iommu_replace_device_pasid(struct iommu_domain *domain, + struct device *dev, ioasid_t pasid) +{ + /* Caller must be a probed driver on dev */ + struct iommu_group *group = dev->iommu_group; + void *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) + return -EINVAL; + + mutex_lock(&group->mutex); + /* + * The recorded domain is inconsistent with the domain pasid is + * actually attached until pasid is attached to the new domain. + * This has race condition with the paths that do not hold + * group->mutex. E.g. the Page Request forwarding. + */ + curr = xa_store(&group->pasid_array, pasid, domain, 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) + goto out_unlock; + + ret = __iommu_set_group_pasid(domain, group, pasid, curr); + if (ret) + WARN_ON(domain != 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.