{"id":2226029,"url":"http://patchwork.ozlabs.org/api/1.2/patches/2226029/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-pci/patch/20260422023239.1171963-8-mrathor@linux.microsoft.com/","project":{"id":28,"url":"http://patchwork.ozlabs.org/api/1.2/projects/28/?format=json","name":"Linux PCI development","link_name":"linux-pci","list_id":"linux-pci.vger.kernel.org","list_email":"linux-pci@vger.kernel.org","web_url":null,"scm_url":null,"webscm_url":null,"list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20260422023239.1171963-8-mrathor@linux.microsoft.com>","list_archive_url":null,"date":"2026-04-22T02:32:33","name":"[V1,07/13] mshv: Add ioctl support for MSHV-VFIO bridge device","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"645b971b908a7c9682a1d0ff50d7d75f27ef09ab","submitter":{"id":91512,"url":"http://patchwork.ozlabs.org/api/1.2/people/91512/?format=json","name":"Mukesh R","email":"mrathor@linux.microsoft.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/linux-pci/patch/20260422023239.1171963-8-mrathor@linux.microsoft.com/mbox/","series":[{"id":500915,"url":"http://patchwork.ozlabs.org/api/1.2/series/500915/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-pci/list/?series=500915","date":"2026-04-22T02:32:26","name":"PCI passthru on Hyper-V (Part I)","version":1,"mbox":"http://patchwork.ozlabs.org/series/500915/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2226029/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2226029/checks/","tags":{},"related":[],"headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linux-pci@vger.kernel.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=linux.microsoft.com header.i=@linux.microsoft.com\n header.a=rsa-sha256 header.s=default header.b=Vr2BHVut;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c04:e001:36c::12fc:5321; helo=tor.lore.kernel.org;\n envelope-from=linux-pci+bounces-52902-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)","smtp.subspace.kernel.org;\n\tdkim=pass (1024-bit key) header.d=linux.microsoft.com\n header.i=@linux.microsoft.com header.b=\"Vr2BHVut\"","smtp.subspace.kernel.org;\n arc=none smtp.client-ip=13.77.154.182","smtp.subspace.kernel.org;\n dmarc=pass (p=none dis=none) header.from=linux.microsoft.com","smtp.subspace.kernel.org;\n spf=pass smtp.mailfrom=linux.microsoft.com"],"Received":["from tor.lore.kernel.org (tor.lore.kernel.org\n [IPv6:2600:3c04:e001:36c::12fc:5321])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4g0k1935yBz1yD5\n\tfor ; Wed, 22 Apr 2026 12:38:21 +1000 (AEST)","from smtp.subspace.kernel.org (conduit.subspace.kernel.org\n [100.90.174.1])\n\tby tor.lore.kernel.org (Postfix) with ESMTP id 7A118308F77D\n\tfor ; Wed, 22 Apr 2026 02:34:45 +0000 (UTC)","from localhost.localdomain (localhost.localdomain [127.0.0.1])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id 1C44B382F1C;\n\tWed, 22 Apr 2026 02:34:08 +0000 (UTC)","from linux.microsoft.com (linux.microsoft.com [13.77.154.182])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id BD1053822AA;\n\tWed, 22 Apr 2026 02:33:50 +0000 (UTC)","from mrdev.corp.microsoft.com\n (192-184-212-33.fiber.dynamic.sonic.net [192.184.212.33])\n\tby linux.microsoft.com (Postfix) with ESMTPSA id B043720B6F20;\n\tTue, 21 Apr 2026 19:33:45 -0700 (PDT)"],"ARC-Seal":"i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1776825241; cv=none;\n b=l1JwkynXCuM+du2XKxDcIhz1QOFvgh4DJfBasm+GcYpryATm419TpnfshZJgcwdgErvYQyS6iLUPO23t5hznyPrwA60RqwvA6iy3MhlaR1gIjgjlY0hXNvewtWp4QNj9UCqg2NW9kePBmGWuFUdxh30vg5wUWLkspY86JrG59O4=","ARC-Message-Signature":"i=1; a=rsa-sha256; d=subspace.kernel.org;\n\ts=arc-20240116; t=1776825241; c=relaxed/simple;\n\tbh=C8TsFVJy+pAFOBhAef081HD3HUSmaQJnLst8p/bA8vk=;\n\th=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References:\n\t MIME-Version;\n b=gO9M8NdemE4bh2vq280HWycHd5xjyErF0mgzi8B2ZLvmpKgkWRsqZBfedCtAoWD1MzoiKsTjq/iNRbDX1RwSmcrP3LfNDZgjJrI7wQfuXHRgwjubLTOGk7KpTPGcfOYMQByAafKjjXap7FUTX5O2XJeA7u3fA73Ihz6EPp/oGD0=","ARC-Authentication-Results":"i=1; smtp.subspace.kernel.org;\n dmarc=pass (p=none dis=none) header.from=linux.microsoft.com;\n spf=pass smtp.mailfrom=linux.microsoft.com;\n dkim=pass (1024-bit key) header.d=linux.microsoft.com\n header.i=@linux.microsoft.com header.b=Vr2BHVut;\n arc=none smtp.client-ip=13.77.154.182","DKIM-Filter":"OpenDKIM Filter v2.11.0 linux.microsoft.com B043720B6F20","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com;\n\ts=default; t=1776825226;\n\tbh=torw1rFNIs6S4jLC1p2Rij05fcbQgV06MR8D7ovym88=;\n\th=From:To:Cc:Subject:Date:In-Reply-To:References:From;\n\tb=Vr2BHVutj1SgonSfVzqIBGit/CYCrmt3i9EL9E7s+WEPffaoxJUZmaOLtA8+8mV/B\n\t cnEX+hEifNEQiJZ7pjhLzeAUZ0zf05/SqosiNGnUJfE+/b5B0XthWnEBi9S35jsAHm\n\t VD3COLKj2+sN5CiLmOzyPdgQQCROIoyojZE+N5+w=","From":"Mukesh R ","To":"hpa@zytor.com,\n\trobin.murphy@arm.com,\n\trobh@kernel.org,\n\twei.liu@kernel.org,\n\tmrathor@linux.microsoft.com,\n\tmhklinux@outlook.com,\n\tmuislam@microsoft.com,\n\tnamjain@linux.microsoft.com,\n\tmagnuskulke@linux.microsoft.com,\n\tanbelski@linux.microsoft.com,\n\tlinux-kernel@vger.kernel.org,\n\tlinux-hyperv@vger.kernel.org,\n\tiommu@lists.linux.dev,\n\tlinux-pci@vger.kernel.org,\n\tlinux-arch@vger.kernel.org","Cc":"kys@microsoft.com,\n\thaiyangz@microsoft.com,\n\tdecui@microsoft.com,\n\tlongli@microsoft.com,\n\ttglx@kernel.org,\n\tmingo@redhat.com,\n\tbp@alien8.de,\n\tdave.hansen@linux.intel.com,\n\tx86@kernel.org,\n\tjoro@8bytes.org,\n\twill@kernel.org,\n\tlpieralisi@kernel.org,\n\tkwilczynski@kernel.org,\n\tbhelgaas@google.com,\n\tarnd@arndb.de","Subject":"[PATCH V1 07/13] mshv: Add ioctl support for MSHV-VFIO bridge device","Date":"Tue, 21 Apr 2026 19:32:33 -0700","Message-ID":"<20260422023239.1171963-8-mrathor@linux.microsoft.com>","X-Mailer":"git-send-email 2.51.2.vfs.0.1","In-Reply-To":"<20260422023239.1171963-1-mrathor@linux.microsoft.com>","References":"<20260422023239.1171963-1-mrathor@linux.microsoft.com>","Precedence":"bulk","X-Mailing-List":"linux-pci@vger.kernel.org","List-Id":"","List-Subscribe":"","List-Unsubscribe":"","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit"},"content":"Add ioctl support for creating MSHV devices for a partition. At\npresent only VFIO device types are supported, but more could be\nadded. At a high level, a partition ioctl to create device verifies\nit is of type VFIO and does some setup for bridge code in mshv_vfio.c.\nAdapted from KVM device ioctls.\n\nCo-developed-by: Wei Liu \nSigned-off-by: Wei Liu \nSigned-off-by: Mukesh R \n---\n drivers/hv/mshv_root_main.c | 116 ++++++++++++++++++++++++++++++++++++\n 1 file changed, 116 insertions(+)","diff":"diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c\nindex 02c107458be9..6ceb5f608589 100644\n--- a/drivers/hv/mshv_root_main.c\n+++ b/drivers/hv/mshv_root_main.c\n@@ -1625,6 +1625,119 @@ mshv_partition_ioctl_initialize(struct mshv_partition *partition)\n \treturn ret;\n }\n \n+static long mshv_device_attr_ioctl(struct mshv_device *mshv_dev, int cmd,\n+\t\t\t\t ulong uarg)\n+{\n+\tstruct mshv_device_attr attr;\n+\tconst struct mshv_device_ops *devops = mshv_dev->device_ops;\n+\n+\tif (copy_from_user(&attr, (void __user *)uarg, sizeof(attr)))\n+\t\treturn -EFAULT;\n+\n+\tswitch (cmd) {\n+\tcase MSHV_SET_DEVICE_ATTR:\n+\t\tif (devops->device_set_attr)\n+\t\t\treturn devops->device_set_attr(mshv_dev, &attr);\n+\t\tbreak;\n+\tcase MSHV_HAS_DEVICE_ATTR:\n+\t\tif (devops->device_has_attr)\n+\t\t\treturn devops->device_has_attr(mshv_dev, &attr);\n+\t\tbreak;\n+\t}\n+\n+\treturn -EPERM;\n+}\n+\n+static long mshv_device_fop_ioctl(struct file *filp, unsigned int cmd,\n+\t\t\t\t ulong uarg)\n+{\n+\tstruct mshv_device *mshv_dev = filp->private_data;\n+\n+\tswitch (cmd) {\n+\tcase MSHV_SET_DEVICE_ATTR:\n+\tcase MSHV_HAS_DEVICE_ATTR:\n+\t\treturn mshv_device_attr_ioctl(mshv_dev, cmd, uarg);\n+\t}\n+\n+\treturn -ENOTTY;\n+}\n+\n+static int mshv_device_fop_release(struct inode *inode, struct file *filp)\n+{\n+\tstruct mshv_device *mshv_dev = filp->private_data;\n+\tstruct mshv_partition *partition = mshv_dev->device_pt;\n+\n+\tif (mshv_dev->device_ops->device_release) {\n+\t\tmutex_lock(&partition->pt_mutex);\n+\t\thlist_del(&mshv_dev->device_ptnode);\n+\t\tmshv_dev->device_ops->device_release(mshv_dev);\n+\t\tmutex_unlock(&partition->pt_mutex);\n+\t}\n+\n+\tmshv_partition_put(partition);\n+\treturn 0;\n+}\n+\n+static const struct file_operations mshv_device_fops = {\n+\t.owner = THIS_MODULE,\n+\t.unlocked_ioctl = mshv_device_fop_ioctl,\n+\t.release = mshv_device_fop_release,\n+};\n+\n+static long mshv_partition_ioctl_create_device(struct mshv_partition *partition,\n+\t\t\t\t\t void __user *uarg)\n+{\n+\tlong rc;\n+\tstruct mshv_create_device devargk;\n+\tstruct mshv_device *mshv_dev;\n+\tconst struct mshv_device_ops *vfio_ops;\n+\n+\tif (copy_from_user(&devargk, uarg, sizeof(devargk)))\n+\t\treturn -EFAULT;\n+\n+\t/* At present, only VFIO is supported */\n+\tif (devargk.type != MSHV_DEV_TYPE_VFIO)\n+\t\treturn -ENODEV;\n+\n+\tif (devargk.flags & MSHV_CREATE_DEVICE_TEST)\n+\t\treturn 0;\n+\n+\t/* This is freed later by mshv_vfio_release_device() */\n+\tmshv_dev = kzalloc(sizeof(*mshv_dev), GFP_KERNEL_ACCOUNT);\n+\tif (mshv_dev == NULL)\n+\t\treturn -ENOMEM;\n+\n+\tvfio_ops = &mshv_vfio_device_ops;\n+\tmshv_dev->device_ops = vfio_ops;\n+\tmshv_dev->device_pt = partition;\n+\n+\trc = vfio_ops->device_create(mshv_dev);\n+\tif (rc < 0) {\n+\t\tkfree(mshv_dev);\n+\t\treturn rc;\n+\t}\n+\n+\thlist_add_head(&mshv_dev->device_ptnode, &partition->pt_devices);\n+\n+\tmshv_partition_get(partition);\n+\trc = anon_inode_getfd(vfio_ops->device_name, &mshv_device_fops,\n+\t\t\t mshv_dev, O_RDWR | O_CLOEXEC);\n+\tif (rc < 0)\n+\t\tgoto undo_out;\n+\n+\tdevargk.fd = rc;\n+\tif (copy_to_user(uarg, &devargk, sizeof(devargk)))\n+\t\treturn -EFAULT; /* cleanup in mshv_device_fop_release() */\n+\n+\treturn 0;\n+\n+undo_out:\n+\thlist_del(&mshv_dev->device_ptnode);\n+\tvfio_ops->device_release(mshv_dev); /* will kfree(mshv_dev) */\n+\tmshv_partition_put(partition);\n+\treturn rc;\n+}\n+\n static long\n mshv_partition_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)\n {\n@@ -1661,6 +1774,9 @@ mshv_partition_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)\n \tcase MSHV_ROOT_HVCALL:\n \t\tret = mshv_ioctl_passthru_hvcall(partition, true, uarg);\n \t\tbreak;\n+\tcase MSHV_CREATE_DEVICE:\n+\t\tret = mshv_partition_ioctl_create_device(partition, uarg);\n+\t\tbreak;\n \tdefault:\n \t\tret = -ENOTTY;\n \t}\n","prefixes":["V1","07/13"]}