From patchwork Fri Feb 18 00:55:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Baolu Lu X-Patchwork-Id: 12750834 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 9DDC8C433F5 for ; Fri, 18 Feb 2022 00:58:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230344AbiBRA6T (ORCPT ); Thu, 17 Feb 2022 19:58:19 -0500 Received: from gmail-smtp-in.l.google.com ([23.128.96.19]:37114 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230334AbiBRA6T (ORCPT ); Thu, 17 Feb 2022 19:58:19 -0500 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D75C637A36; Thu, 17 Feb 2022 16:58:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1645145884; x=1676681884; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Z96GxEBC+Q+GUaDOqHkjPNoRKRZDT2uZ37npGzcnohE=; b=gRP+pINoYn9dK+OeDV8dNfiGEG4wY7KyRjd6/OFOpkikS/UlRAbX+WKl h9HS+zorjCdGSnh/1CO/ZndQnQsEIdRLhU/NVQzANgW89x6QoUHuP2WKS vKwmhKozJfKCxp929KQy9xu53USAW+QpQWqdeUSixez/wHdbcvmFZKES3 eDIx1MhJaKRCJPGWyW8EqEiZUgdS5/U76FK9nu3BXr2OORfFhabNT/J+z AQMX6eY75DfiufwxmoK0upEK2ultROQyu1U43O8RgAmrXIOLtweT98bY5 p9iKxy4si0OLVPxJEc08KQxlXoZSCs4QQZr+NcpUr9VguF3WN7GcjbDOA w==; X-IronPort-AV: E=McAfee;i="6200,9189,10261"; a="231655710" X-IronPort-AV: E=Sophos;i="5.88,377,1635231600"; d="scan'208";a="231655710" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Feb 2022 16:57:53 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,377,1635231600"; d="scan'208";a="637491390" Received: from allen-box.sh.intel.com ([10.239.159.118]) by orsmga004.jf.intel.com with ESMTP; 17 Feb 2022 16:57:45 -0800 From: Lu Baolu To: Greg Kroah-Hartman , Joerg Roedel , Alex Williamson , Bjorn Helgaas , Jason Gunthorpe , Christoph Hellwig , Kevin Tian , Ashok Raj Cc: Will Deacon , Robin Murphy , 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 v6 08/11] vfio: Remove use of vfio_group_viable() Date: Fri, 18 Feb 2022 08:55:18 +0800 Message-Id: <20220218005521.172832-9-baolu.lu@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220218005521.172832-1-baolu.lu@linux.intel.com> References: <20220218005521.172832-1-baolu.lu@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org As DMA ownership is claimed for the iommu group when a VFIO group is added to a VFIO container, the VFIO group viability is guaranteed as long as group->container_users > 0. Remove those unnecessary group viability checks which are only hit when group->container_users is not zero. The only remaining reference is in GROUP_GET_STATUS, which could be called at any time when group fd is valid. Here we just replace the vfio_group_viable() by directly calling IOMMU core to get viability status. Signed-off-by: Lu Baolu --- drivers/vfio/vfio.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index df9d4b60e5ae..73034446e03f 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1313,12 +1313,6 @@ static int vfio_group_set_container(struct vfio_group *group, int container_fd) return ret; } -static bool vfio_group_viable(struct vfio_group *group) -{ - return (iommu_group_for_each_dev(group->iommu_group, - group, vfio_dev_viable) == 0); -} - static int vfio_group_add_container_user(struct vfio_group *group) { if (!atomic_inc_not_zero(&group->container_users)) @@ -1328,7 +1322,7 @@ static int vfio_group_add_container_user(struct vfio_group *group) atomic_dec(&group->container_users); return -EPERM; } - if (!group->container->iommu_driver || !vfio_group_viable(group)) { + if (!group->container->iommu_driver) { atomic_dec(&group->container_users); return -EINVAL; } @@ -1346,7 +1340,7 @@ static int vfio_group_get_device_fd(struct vfio_group *group, char *buf) int ret = 0; if (0 == atomic_read(&group->container_users) || - !group->container->iommu_driver || !vfio_group_viable(group)) + !group->container->iommu_driver) return -EINVAL; if (group->type == VFIO_NO_IOMMU && !capable(CAP_SYS_RAWIO)) @@ -1438,11 +1432,11 @@ static long vfio_group_fops_unl_ioctl(struct file *filep, status.flags = 0; - if (vfio_group_viable(group)) - status.flags |= VFIO_GROUP_FLAGS_VIABLE; - if (group->container) - status.flags |= VFIO_GROUP_FLAGS_CONTAINER_SET; + status.flags |= VFIO_GROUP_FLAGS_CONTAINER_SET | + VFIO_GROUP_FLAGS_VIABLE; + else if (!iommu_group_dma_owner_claimed(group->iommu_group)) + status.flags |= VFIO_GROUP_FLAGS_VIABLE; if (copy_to_user((void __user *)arg, &status, minsz)) return -EFAULT;