From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sinmsgout01.his.huawei.com (sinmsgout01.his.huawei.com [119.8.177.36]) (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 E063D33993; Tue, 29 Jul 2025 16:46:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=119.8.177.36 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753807598; cv=none; b=tAXQM8HFMkZczCj8AEBOj7Q7jwmIRqO+RICAK/wyBW5TXm3+pJTjktwj9PUvEO/bL9jh368HJ96DojW5L/4LkHkv7b8AUEV3Zt8Z+RoBzym2SVpJ0qHz6F0tpyJ6VAMacRgZjGEPyMKfpwUFdL3ojvTqC5pC9amKr80QGlOMdF0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753807598; c=relaxed/simple; bh=XfV9U757F5SWpS2wnRxcpkAv+nxMq3qw2d8jQ0oRxI0=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=skOqcPv75SOkCNCS6h2JKPXU2xiYgB5LVIWk2U+0LvmpCHkb28u9qgxVCYFh4QBbPYvJNLgSpnacQXeJlL9l89VcAhSaZLqUS6hnN7+tiSJsU8Fn+FyhY7MGdVKoRdvCxxuKCgai+r4tQ8iZtBBehgaYhxDQE1+sHpwxfkHX2X4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b=vWje3sxd; arc=none smtp.client-ip=119.8.177.36 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b="vWje3sxd" dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=Npn5Ah8PAw6fNiXtXhHXUfjg5csWz/60SorhwBN4vyM=; b=vWje3sxdNJvVdik1CWixLNkOCQ3onRhSINZOQOp/OUhmdh/keDwDBbbYt6anZwvx1nGNpXi0F MIdToAMHZJRqZkpNBDuy02GcsN9O5kkkn80yDym09SgsCKVGrAk/E0G0gAn+MiE84Xi1r1PetJQ R1zGfRQnoh1L+gxeGAEYmbI= Received: from frasgout.his.huawei.com (unknown [172.18.146.35]) by sinmsgout01.his.huawei.com (SkyGuard) with ESMTPS id 4bs10J6hVFz1P6lQ; Wed, 30 Jul 2025 00:25:04 +0800 (CST) Received: from mail.maildlp.com (unknown [172.18.186.231]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4bs1015Q1Wz6H7HH; Wed, 30 Jul 2025 00:24:49 +0800 (CST) Received: from frapeml500008.china.huawei.com (unknown [7.182.85.71]) by mail.maildlp.com (Postfix) with ESMTPS id 6987B140427; Wed, 30 Jul 2025 00:26:24 +0800 (CST) Received: from localhost (10.203.177.66) by frapeml500008.china.huawei.com (7.182.85.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Tue, 29 Jul 2025 18:26:23 +0200 Date: Tue, 29 Jul 2025 17:26:21 +0100 From: Jonathan Cameron To: "Aneesh Kumar K.V (Arm)" CC: , , , , , , Samuel Ortiz , Xu Yilun , Jason Gunthorpe , "Suzuki K Poulose" , Steven Price , Catalin Marinas , Marc Zyngier , Will Deacon , Oliver Upton Subject: Re: [RFC PATCH v1 07/38] iommufd/viommu: Add support to associate viommu with kvm instance Message-ID: <20250729172621.00006344@huawei.com> In-Reply-To: <20250728135216.48084-8-aneesh.kumar@kernel.org> References: <20250728135216.48084-1-aneesh.kumar@kernel.org> <20250728135216.48084-8-aneesh.kumar@kernel.org> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.42; x86_64-w64-mingw32) Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: lhrpeml500009.china.huawei.com (7.191.174.84) To frapeml500008.china.huawei.com (7.182.85.71) On Mon, 28 Jul 2025 19:21:44 +0530 "Aneesh Kumar K.V (Arm)" wrote: > The associated kvm instance will be used in later patch by iommufd to > bind a tdi to kvm. > > Signed-off-by: Aneesh Kumar K.V (Arm) > --- > drivers/iommu/iommufd/viommu.c | 45 +++++++++++++++++++++++++++++++++- > include/linux/iommufd.h | 3 +++ > include/uapi/linux/iommufd.h | 12 +++++++++ > 3 files changed, 59 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/iommufd/viommu.c b/drivers/iommu/iommufd/viommu.c > index 2ca5809b238b..59f1e1176f7f 100644 > --- a/drivers/iommu/iommufd/viommu.c > +++ b/drivers/iommu/iommufd/viommu.c > @@ -2,6 +2,36 @@ > /* Copyright (c) 2024, NVIDIA CORPORATION & AFFILIATES > */ > #include "iommufd_private.h" > +#include "linux/tsm.h" > + > +#if IS_ENABLED(CONFIG_KVM) > +#include > + > +static int viommu_get_kvm(struct iommufd_viommu *viommu, int kvm_vm_fd) > +{ > + int rc = -EBADF; > + struct file *filp; > + > + filp = fget(kvm_vm_fd); > + > + if (!file_is_kvm(filp)) > + goto err_out; > + > + /* hold the kvm reference via file descriptor */ > + viommu->kvm_filp = filp; > + return 0; > +err_out: > + viommu->kvm_filp = NULL; Is this to undo side effects from this function on error? kvm_filp is only set after all error paths so maybe this isn't needed? If this isn't needed then use __free(fput) and no_free_ptr() to deal with filp more simply and in teh erorr path can just return -EBADF directly rather than the goto. Or are we avoiding that stuff in iommufd? > + fput(filp); > + return rc; > +} > + > +static void viommu_put_kvm(struct iommufd_viommu *viommu) > +{ > + fput(viommu->kvm_filp); > + viommu->kvm_filp = NULL; > +} > +#endif