From patchwork Thu Feb 9 04:16:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yi Liu X-Patchwork-Id: 13133940 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 40103C05027 for ; Thu, 9 Feb 2023 04:20:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229479AbjBIEUR (ORCPT ); Wed, 8 Feb 2023 23:20:17 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229564AbjBIEUO (ORCPT ); Wed, 8 Feb 2023 23:20:14 -0500 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D86A0125AE; Wed, 8 Feb 2023 20:19:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1675916360; x=1707452360; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Zg75NlnzG6bl+FEokzV5mm4wJdtzxfEPl+1gdcoX9v4=; b=WZXVMdplkhYeXlnDg6B7TelrovySZiy+APS08/1iBteCNqI41nyFzYKj dyCTzInlDBZbK4qr2Lp3z6kdObpT+tu6tkEiOMiQwhbmv7F3MHsmNmfnt 88mcbJLZR2PGR/8TULYEBJ91K9vDLXf5sVzdxjZfl0RXrx5ZEEihRK2l+ eFN4AgREXOvJ2XdQCzrW1JkzkKZf10RZJu6nELnrRjlk8xdbh4Tr0b2y/ y5fl0b4ANRE09JTp41uHjLjOTlji493IiGx99hyCJOCj1Vcfxi2OXcAC5 CLq78y2smkZdwACzfk9DcxZF2w0meBYnXIBTWNx+NiLkVcP10nGhwfuk0 Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10615"; a="394600728" X-IronPort-AV: E=Sophos;i="5.97,281,1669104000"; d="scan'208";a="394600728" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Feb 2023 20:16:51 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10615"; a="912982101" X-IronPort-AV: E=Sophos;i="5.97,281,1669104000"; d="scan'208";a="912982101" Received: from 984fee00a4c6.jf.intel.com ([10.165.58.231]) by fmsmga006.fm.intel.com with ESMTP; 08 Feb 2023 20:16:49 -0800 From: Yi Liu To: joro@8bytes.org, alex.williamson@redhat.com, jgg@nvidia.com, kevin.tian@intel.com, robin.murphy@arm.com Cc: cohuck@redhat.com, eric.auger@redhat.com, nicolinc@nvidia.com, kvm@vger.kernel.org, mjrosato@linux.ibm.com, chao.p.peng@linux.intel.com, yi.l.liu@intel.com, yi.y.sun@linux.intel.com, peterx@redhat.com, jasowang@redhat.com, shameerali.kolothum.thodi@huawei.com, lulu@redhat.com, suravee.suthikulpanit@amd.com, iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, baolu.lu@linux.intel.com Subject: [PATCH 3/6] iommufd: Add IOMMU_DEVICE_GET_INFO Date: Wed, 8 Feb 2023 20:16:39 -0800 Message-Id: <20230209041642.9346-4-yi.l.liu@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230209041642.9346-1-yi.l.liu@intel.com> References: <20230209041642.9346-1-yi.l.liu@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Under nested IOMMU translation, userspace owns the stage-1 translation structure (e.g. the stage-1 page table of Intel VT-d or the context table of ARM SMMUv3, and etc.). Such stage-1 translation structures are vendor specific, and needs to be compatiable with the underlying IOMMU hardware. Hence, userspace should know the IOMMU hardware capability before creating and configuring the stage-1 translation structure to kernel. This adds ioctl: IOMMU_DEVICE_GET_INFO to query the IOMMU hardware capability for a given device. The returned data is vendor specific, userspace can tell it by the @out_device_type field. Signed-off-by: Nicolin Chen Signed-off-by: Yi Liu --- drivers/iommu/iommufd/device.c | 72 +++++++++++++++++++++++++ drivers/iommu/iommufd/iommufd_private.h | 1 + drivers/iommu/iommufd/main.c | 3 ++ include/uapi/linux/iommufd.h | 36 +++++++++++++ 4 files changed, 112 insertions(+) diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c index 8a9834fc129a..3b64aef24807 100644 --- a/drivers/iommu/iommufd/device.c +++ b/drivers/iommu/iommufd/device.c @@ -134,6 +134,78 @@ void iommufd_device_unbind(struct iommufd_device *idev) } EXPORT_SYMBOL_NS_GPL(iommufd_device_unbind, IOMMUFD); +static int iommufd_zero_fill_user(u64 ptr, int bytes) +{ + int index = 0; + + for (; index < bytes; index++) { + if (put_user(0, (uint8_t __user *)(ptr + index))) + return -EFAULT; + } + return 0; +} + +int iommufd_device_get_info(struct iommufd_ucmd *ucmd) +{ + struct iommu_device_info *cmd = ucmd->cmd; + struct iommufd_object *dev_obj; + struct device *dev; + const struct iommu_ops *ops; + void *data; + unsigned int length, data_len; + int rc; + + if (cmd->flags || cmd->__reserved || !cmd->data_len) + return -EOPNOTSUPP; + + dev_obj = iommufd_get_object(ucmd->ictx, cmd->dev_id, + IOMMUFD_OBJ_DEVICE); + if (IS_ERR(dev_obj)) + return PTR_ERR(dev_obj); + + dev = container_of(dev_obj, struct iommufd_device, obj)->dev; + + ops = dev_iommu_ops(dev); + if (!ops || !ops->hw_info) { + rc = -EOPNOTSUPP; + goto out_put; + } + + data = ops->hw_info(dev, &data_len); + if (IS_ERR(data)) { + rc = PTR_ERR(data); + goto out_put; + } + + length = min(cmd->data_len, data_len); + if (copy_to_user(u64_to_user_ptr(cmd->data_ptr), data, length)) { + rc = -EFAULT; + goto out_free_data; + } + + /* + * Zero the trailing bytes for userspace if the buffer is bigger + * than the data size kernel actually has. + */ + if (length < cmd->data_len) { + rc = iommufd_zero_fill_user(cmd->data_ptr + length, + cmd->data_len - length); + if (rc) + goto out_free_data; + } + + cmd->out_device_type = ops->driver_type; + cmd->data_len = data_len; + + rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd)); + +out_free_data: + kfree(data); +out_put: + iommufd_put_object(dev_obj); + return rc; +} + static int iommufd_device_setup_msi(struct iommufd_device *idev, struct iommufd_hw_pagetable *hwpt, phys_addr_t sw_msi_start) diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h index 200c783800ad..4a0a1a7fdae1 100644 --- a/drivers/iommu/iommufd/iommufd_private.h +++ b/drivers/iommu/iommufd/iommufd_private.h @@ -258,6 +258,7 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, void iommufd_hw_pagetable_destroy(struct iommufd_object *obj); void iommufd_device_destroy(struct iommufd_object *obj); +int iommufd_device_get_info(struct iommufd_ucmd *ucmd); struct iommufd_access { struct iommufd_object obj; diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c index 3fbe636c3d8a..59aa30ad1090 100644 --- a/drivers/iommu/iommufd/main.c +++ b/drivers/iommu/iommufd/main.c @@ -250,6 +250,7 @@ static int iommufd_option(struct iommufd_ucmd *ucmd) union ucmd_buffer { struct iommu_destroy destroy; + struct iommu_device_info info; struct iommu_ioas_alloc alloc; struct iommu_ioas_allow_iovas allow_iovas; struct iommu_ioas_copy ioas_copy; @@ -281,6 +282,8 @@ struct iommufd_ioctl_op { } static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = { IOCTL_OP(IOMMU_DESTROY, iommufd_destroy, struct iommu_destroy, id), + IOCTL_OP(IOMMU_DEVICE_GET_INFO, iommufd_device_get_info, struct iommu_device_info, + __reserved), IOCTL_OP(IOMMU_IOAS_ALLOC, iommufd_ioas_alloc_ioctl, struct iommu_ioas_alloc, out_ioas_id), IOCTL_OP(IOMMU_IOAS_ALLOW_IOVAS, iommufd_ioas_allow_iovas, diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index fda75c8450ee..6cfe102f26f3 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -45,6 +45,7 @@ enum { IOMMUFD_CMD_IOAS_UNMAP, IOMMUFD_CMD_OPTION, IOMMUFD_CMD_VFIO_IOAS, + IOMMUFD_CMD_DEVICE_GET_INFO, }; /** @@ -371,4 +372,39 @@ struct iommu_device_info_vtd { __aligned_u64 cap_reg; __aligned_u64 ecap_reg; }; + +/** + * struct iommu_device_info - ioctl(IOMMU_DEVICE_GET_INFO) + * @size: sizeof(struct iommu_device_info) + * @flags: Must be 0 + * @dev_id: The device being attached to the IOMMU + * @data_len: Input the type specific data buffer length in bytes + * @data_ptr: Pointer to the type specific structure (e.g. + * struct iommu_device_info_vtd) + * @out_device_type: Output the underlying iommu hardware type, it is + * one of enum iommu_device_data_type. + * @__reserved: Must be 0 + * + * Query the hardware iommu capability for given device which has been + * bound to iommufd. @data_len is set to be the size of the buffer to + * type specific data and the data will be filled. Trailing bytes are + * zeroed if the user buffer is larger than the data kernel has. + * + * The type specific data would be used to sync capability between the + * vIOMMU and the hardware IOMMU, also for the availabillity checking of + * iommu hardware features like dirty page tracking in I/O page table. + * + * The @out_device_type will be filled if the ioctl succeeds. It would + * be used to decode the data filled in the buffer pointed by @data_ptr. + */ +struct iommu_device_info { + __u32 size; + __u32 flags; + __u32 dev_id; + __u32 data_len; + __aligned_u64 data_ptr; + __u32 out_device_type; + __u32 __reserved; +}; +#define IOMMU_DEVICE_GET_INFO _IO(IOMMUFD_TYPE, IOMMUFD_CMD_DEVICE_GET_INFO) #endif