From patchwork Thu Oct 26 10:31:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Duan, Zhenzhong" X-Patchwork-Id: 13437493 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 86DC9C25B70 for ; Thu, 26 Oct 2023 10:51:33 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qvxvL-0004Hv-JY; Thu, 26 Oct 2023 06:49:11 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qvxvJ-0004EJ-JP for qemu-devel@nongnu.org; Thu, 26 Oct 2023 06:49:09 -0400 Received: from mgamail.intel.com ([134.134.136.126]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qvxvH-0001PR-9a for qemu-devel@nongnu.org; Thu, 26 Oct 2023 06:49:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1698317347; x=1729853347; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=unz1VcERlRWpgvRCFPYWoFixGJk6XxMNh9+O79XWD54=; b=L2SXLZimAKpjM5Wxdsr26GoafZC2Litb3s6B/b2jhqQbeQ9LTkSjqt+Q FHs7WZ0WbEz7lR3A350jnxlpjNGYTwApzuRwwzZ6Ww0esH//krAkpQKwW MhE9eDIk0sGyKg34BwMLXGlLC8NFZPm4bUZDpL/VN6XLWNXioAEa76faG mD6ZJH0zCTWnrsZQMXYlY2ne9GC14j0S6EyXCQrlckXmZIUQa0fuo3S9h jH64bWMDCNISvF6jXSVyNH3KazrlFoFp5oxGD+WJPND40l7qYV0jVThf1 9U+24wvr5YSFFuerMvqWcTAH534arw22VQztDxmhdzSuvETqr1Q6TnhRF A==; X-IronPort-AV: E=McAfee;i="6600,9927,10874"; a="372563829" X-IronPort-AV: E=Sophos;i="6.03,253,1694761200"; d="scan'208";a="372563829" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Oct 2023 03:48:22 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.03,253,1694761200"; d="scan'208";a="463854" Received: from duan-server-s2600bt.bj.intel.com ([10.240.192.147]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Oct 2023 03:48:07 -0700 From: Zhenzhong Duan To: qemu-devel@nongnu.org Cc: alex.williamson@redhat.com, clg@redhat.com, jgg@nvidia.com, nicolinc@nvidia.com, joao.m.martins@oracle.com, eric.auger@redhat.com, peterx@redhat.com, jasowang@redhat.com, kevin.tian@intel.com, yi.l.liu@intel.com, yi.y.sun@intel.com, chao.p.peng@intel.com, Zhenzhong Duan Subject: [PATCH v3 33/37] vfio/pci: Make vfio cdev pre-openable by passing a file handle Date: Thu, 26 Oct 2023 18:31:00 +0800 Message-Id: <20231026103104.1686921-34-zhenzhong.duan@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231026103104.1686921-1-zhenzhong.duan@intel.com> References: <20231026103104.1686921-1-zhenzhong.duan@intel.com> MIME-Version: 1.0 Received-SPF: pass client-ip=134.134.136.126; envelope-from=zhenzhong.duan@intel.com; helo=mgamail.intel.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This gives management tools like libvirt a chance to open the vfio cdev with privilege and pass FD to qemu. This way qemu never needs to have privilege to open a VFIO or iommu cdev node. Together with the earlier support of pre-opening /dev/iommu device, now we have full support of passing a vfio device to unprivileged qemu by management tool. This mode is no more considered for the legacy backend. So let's remove the "TODO" comment. Add a helper function vfio_device_get_name() to check fd and get device name, it will also be used by other vfio devices. There is no easy way to check if a device is mdev with FD passing, so fail the x-balloon-allowed check unconditionally in this case. There is also no easy way to get BDF as name with FD passing, so we fake a name by VFIO_FD[fd]. Signed-off-by: Zhenzhong Duan Signed-off-by: Cédric Le Goater --- include/hw/vfio/vfio-common.h | 1 + hw/vfio/helpers.c | 33 +++++++++++++++++++++++++++++ hw/vfio/iommufd.c | 12 +++++++---- hw/vfio/pci.c | 40 ++++++++++++++++++++++++----------- 4 files changed, 70 insertions(+), 16 deletions(-) diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h index 95afee7243..5c00699290 100644 --- a/include/hw/vfio/vfio-common.h +++ b/include/hw/vfio/vfio-common.h @@ -258,6 +258,7 @@ struct vfio_info_cap_header * vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id); struct vfio_info_cap_header * vfio_get_cap(void *ptr, uint32_t cap_offset, uint16_t id); +int vfio_device_get_name(VFIODevice *vbasedev, Error **errp); #endif bool vfio_migration_realize(VFIODevice *vbasedev, Error **errp); diff --git a/hw/vfio/helpers.c b/hw/vfio/helpers.c index 168847e7c5..044dbbc501 100644 --- a/hw/vfio/helpers.c +++ b/hw/vfio/helpers.c @@ -609,3 +609,36 @@ bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type) return ret; } + +int vfio_device_get_name(VFIODevice *vbasedev, Error **errp) +{ + struct stat st; + + if (vbasedev->fd < 0) { + if (stat(vbasedev->sysfsdev, &st) < 0) { + error_setg_errno(errp, errno, "no such host device"); + error_prepend(errp, VFIO_MSG_PREFIX, vbasedev->sysfsdev); + return -errno; + } + /* User may specify a name, e.g: VFIO platform device */ + if (!vbasedev->name) { + vbasedev->name = g_path_get_basename(vbasedev->sysfsdev); + } + } +#ifdef CONFIG_IOMMUFD + else { + if (!vbasedev->iommufd) { + error_setg(errp, "Use FD passing only with iommufd backend"); + return -EINVAL; + } + /* + * Give a name with fd so any function printing out vbasedev->name + * will not break. + */ + if (!vbasedev->name) { + vbasedev->name = g_strdup_printf("VFIO_FD%d", vbasedev->fd); + } + } +#endif + return 0; +} diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c index 18a09d7f5a..20df807d7c 100644 --- a/hw/vfio/iommufd.c +++ b/hw/vfio/iommufd.c @@ -405,11 +405,15 @@ static int iommufd_attach_device(char *name, VFIODevice *vbasedev, uint32_t ioas_id; Error *err = NULL; - devfd = vfio_get_devicefd(vbasedev->sysfsdev, errp); - if (devfd < 0) { - return devfd; + if (vbasedev->fd < 0) { + devfd = vfio_get_devicefd(vbasedev->sysfsdev, errp); + if (devfd < 0) { + return devfd; + } + vbasedev->fd = devfd; + } else { + devfd = vbasedev->fd; } - vbasedev->fd = devfd; ret = iommufd_connect_and_bind(vbasedev, errp); if (ret) { diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 386c08576a..32a4e8beb0 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -44,6 +44,7 @@ #include "migration/qemu-file.h" #include "linux/iommufd.h" #include "sysemu/iommufd.h" +#include "monitor/monitor.h" #define TYPE_VFIO_PCI_NOHOTPLUG "vfio-pci-nohotplug" @@ -3267,18 +3268,23 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) VFIODevice *vbasedev = &vdev->vbasedev; char *tmp, *subsys; Error *err = NULL; - struct stat st; int i, ret; bool is_mdev; char uuid[UUID_FMT_LEN]; char *name; - if (!vbasedev->sysfsdev) { + if (vbasedev->fd < 0 && !vbasedev->sysfsdev) { if (!(~vdev->host.domain || ~vdev->host.bus || ~vdev->host.slot || ~vdev->host.function)) { error_setg(errp, "No provided host device"); +#ifdef CONFIG_IOMMUFD + error_append_hint(errp, "Use -device vfio-pci,host=DDDD:BB:DD.F, " + "-device vfio-pci,sysfsdev=PATH_TO_DEVICE " + "or -device vfio-pci,fd=DEVICE_FD\n"); +#else error_append_hint(errp, "Use -device vfio-pci,host=DDDD:BB:DD.F " "or -device vfio-pci,sysfsdev=PATH_TO_DEVICE\n"); +#endif return; } vbasedev->sysfsdev = @@ -3287,13 +3293,9 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) vdev->host.slot, vdev->host.function); } - if (stat(vbasedev->sysfsdev, &st) < 0) { - error_setg_errno(errp, errno, "no such host device"); - error_prepend(errp, VFIO_MSG_PREFIX, vbasedev->sysfsdev); + if (vfio_device_get_name(vbasedev, errp)) { return; } - - vbasedev->name = g_path_get_basename(vbasedev->sysfsdev); vbasedev->ops = &vfio_pci_ops; vbasedev->type = VFIO_DEVICE_TYPE_PCI; vbasedev->dev = DEVICE(vdev); @@ -3653,6 +3655,7 @@ static void vfio_instance_init(Object *obj) vdev->host.bus = ~0U; vdev->host.slot = ~0U; vdev->host.function = ~0U; + vdev->vbasedev.fd = -1; vdev->nv_gpudirect_clique = 0xFF; @@ -3706,11 +3709,6 @@ static Property vfio_pci_dev_properties[] = { qdev_prop_nv_gpudirect_clique, uint8_t), DEFINE_PROP_OFF_AUTO_PCIBAR("x-msix-relocation", VFIOPCIDevice, msix_relo, OFF_AUTOPCIBAR_OFF), - /* - * TODO - support passed fds... is this necessary? - * DEFINE_PROP_STRING("vfiofd", VFIOPCIDevice, vfiofd_name), - * DEFINE_PROP_STRING("vfiogroupfd, VFIOPCIDevice, vfiogroupfd_name), - */ #ifdef CONFIG_IOMMUFD DEFINE_PROP_LINK("iommufd", VFIOPCIDevice, vbasedev.iommufd, TYPE_IOMMUFD_BACKEND, IOMMUFDBackend *), @@ -3718,6 +3716,21 @@ static Property vfio_pci_dev_properties[] = { DEFINE_PROP_END_OF_LIST(), }; +#ifdef CONFIG_IOMMUFD +static void vfio_pci_set_fd(Object *obj, const char *str, Error **errp) +{ + VFIOPCIDevice *vdev = VFIO_PCI(obj); + int fd = -1; + + fd = monitor_fd_param(monitor_cur(), str, errp); + if (fd == -1) { + error_prepend(errp, "Could not parse remote object fd %s:", str); + return; + } + vdev->vbasedev.fd = fd; +} +#endif + static void vfio_pci_dev_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); @@ -3725,6 +3738,9 @@ static void vfio_pci_dev_class_init(ObjectClass *klass, void *data) dc->reset = vfio_pci_reset; device_class_set_props(dc, vfio_pci_dev_properties); +#ifdef CONFIG_IOMMUFD + object_class_property_add_str(klass, "fd", NULL, vfio_pci_set_fd); +#endif dc->desc = "VFIO-based PCI device assignment"; set_bit(DEVICE_CATEGORY_MISC, dc->categories); pdc->realize = vfio_realize;