From nobody Wed Nov 27 00:48:05 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1703012847772746.3578032689101; Tue, 19 Dec 2023 11:07:27 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rFfL7-0007pz-59; Tue, 19 Dec 2023 14:01:13 -0500 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 1rFfJW-00055F-Sz for qemu-devel@nongnu.org; Tue, 19 Dec 2023 13:59:36 -0500 Received: from gandalf.ozlabs.org ([150.107.74.76]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rFfJT-0007Ru-Je for qemu-devel@nongnu.org; Tue, 19 Dec 2023 13:59:34 -0500 Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by gandalf.ozlabs.org (Postfix) with ESMTP id 4SvmFs4Tw9z4xQj; Wed, 20 Dec 2023 05:59:29 +1100 (AEDT) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4SvmFn23P6z4xCp; Wed, 20 Dec 2023 05:59:24 +1100 (AEDT) From: =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= To: qemu-devel@nongnu.org Cc: Eric Auger , Zhenzhong Duan , Peter Maydell , Richard Henderson , Nicholas Piggin , Harsh Prateek Bora , Thomas Huth , Eric Farman , Alex Williamson , Matthew Rosato , =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= , Nicolin Chen Subject: [PULL 30/47] vfio/pci: Make vfio cdev pre-openable by passing a file handle Date: Tue, 19 Dec 2023 19:56:26 +0100 Message-ID: <20231219185643.725448-31-clg@redhat.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231219185643.725448-1-clg@redhat.com> References: <20231219185643.725448-1-clg@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=150.107.74.76; envelope-from=SRS0=7/MV=H6=redhat.com=clg@ozlabs.org; helo=gandalf.ozlabs.org X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.25, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no 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+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZM-MESSAGEID: 1703012849723100011 From: Zhenzhong Duan 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 helper functions vfio_device_set_fd() and vfio_device_get_name() to set fd and get device name, they 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 Reviewed-by: C=C3=A9dric Le Goater Tested-by: Eric Auger Tested-by: Nicolin Chen Signed-off-by: C=C3=A9dric Le Goater --- include/hw/vfio/vfio-common.h | 4 ++++ hw/vfio/helpers.c | 43 +++++++++++++++++++++++++++++++++++ hw/vfio/iommufd.c | 12 ++++++---- hw/vfio/pci.c | 28 +++++++++++++---------- 4 files changed, 71 insertions(+), 16 deletions(-) diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h index 3dac5c167efa1fc6afefc103539ce5e01cceb602..697bf24a350d5880e59811322d9= 037575a90d9a2 100644 --- a/include/hw/vfio/vfio-common.h +++ b/include/hw/vfio/vfio-common.h @@ -251,4 +251,8 @@ int vfio_devices_query_dirty_bitmap(VFIOContainerBase *= bcontainer, hwaddr size); int vfio_get_dirty_bitmap(VFIOContainerBase *bcontainer, uint64_t iova, uint64_t size, ram_addr_t ram_addr); + +/* Returns 0 on success, or a negative errno. */ +int vfio_device_get_name(VFIODevice *vbasedev, Error **errp); +void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **err= p); #endif /* HW_VFIO_VFIO_COMMON_H */ diff --git a/hw/vfio/helpers.c b/hw/vfio/helpers.c index 168847e7c51ef35afbea276745c1aa7e6cd94ce0..3592c3d54ecd68d4bfd23d4c340= 2a393fb1f2eb0 100644 --- a/hw/vfio/helpers.c +++ b/hw/vfio/helpers.c @@ -27,6 +27,7 @@ #include "trace.h" #include "qapi/error.h" #include "qemu/error-report.h" +#include "monitor/monitor.h" =20 /* * Common VFIO interrupt disable @@ -609,3 +610,45 @@ bool vfio_has_region_cap(VFIODevice *vbasedev, int reg= ion, uint16_t cap_type) =20 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 =3D g_path_get_basename(vbasedev->sysfsdev); + } + } 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 =3D g_strdup_printf("VFIO_FD%d", vbasedev->fd); + } + } + + return 0; +} + +void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **err= p) +{ + int fd =3D monitor_fd_param(monitor_cur(), str, errp); + + if (fd < 0) { + error_prepend(errp, "Could not parse remote object fd %s:", str); + return; + } + vbasedev->fd =3D fd; +} diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c index 6e53e013ef57b6d7e3be58e61356fbabacbe8bf3..5accd2648444defcd698bd6d0ce= fe11d255b4cfb 100644 --- a/hw/vfio/iommufd.c +++ b/hw/vfio/iommufd.c @@ -320,11 +320,15 @@ static int iommufd_cdev_attach(const char *name, VFIO= Device *vbasedev, uint32_t ioas_id; Error *err =3D NULL; =20 - devfd =3D iommufd_cdev_getfd(vbasedev->sysfsdev, errp); - if (devfd < 0) { - return devfd; + if (vbasedev->fd < 0) { + devfd =3D iommufd_cdev_getfd(vbasedev->sysfsdev, errp); + if (devfd < 0) { + return devfd; + } + vbasedev->fd =3D devfd; + } else { + devfd =3D vbasedev->fd; } - vbasedev->fd =3D devfd; =20 ret =3D iommufd_cdev_connect_and_bind(vbasedev, errp); if (ret) { diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index c5984b0598d26e7dd31fdb12dccac2e3ca81adf3..445d58c8e59b0a00a8336d092c2= b8cec7e39b396 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -2944,17 +2944,19 @@ static void vfio_realize(PCIDevice *pdev, Error **e= rrp) VFIODevice *vbasedev =3D &vdev->vbasedev; char *tmp, *subsys; Error *err =3D NULL; - struct stat st; int i, ret; bool is_mdev; char uuid[UUID_STR_LEN]; char *name; =20 - 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"); error_append_hint(errp, "Use -device vfio-pci,host=3DDDDD:BB:D= D.F " +#ifdef CONFIG_IOMMUFD + "or -device vfio-pci,fd=3DDEVICE_FD " +#endif "or -device vfio-pci,sysfsdev=3DPATH_TO_DEVI= CE\n"); return; } @@ -2964,13 +2966,9 @@ static void vfio_realize(PCIDevice *pdev, Error **er= rp) vdev->host.slot, vdev->host.function); } =20 - 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) < 0) { return; } - - vbasedev->name =3D g_path_get_basename(vbasedev->sysfsdev); vbasedev->ops =3D &vfio_pci_ops; vbasedev->type =3D VFIO_DEVICE_TYPE_PCI; vbasedev->dev =3D DEVICE(vdev); @@ -3330,6 +3328,7 @@ static void vfio_instance_init(Object *obj) vdev->host.bus =3D ~0U; vdev->host.slot =3D ~0U; vdev->host.function =3D ~0U; + vdev->vbasedev.fd =3D -1; =20 vdev->nv_gpudirect_clique =3D 0xFF; =20 @@ -3383,11 +3382,6 @@ static Property vfio_pci_dev_properties[] =3D { qdev_prop_nv_gpudirect_clique, uint8_t), DEFINE_PROP_OFF_AUTO_PCIBAR("x-msix-relocation", VFIOPCIDevice, msix_r= elo, 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 *), @@ -3395,6 +3389,13 @@ static Property vfio_pci_dev_properties[] =3D { DEFINE_PROP_END_OF_LIST(), }; =20 +#ifdef CONFIG_IOMMUFD +static void vfio_pci_set_fd(Object *obj, const char *str, Error **errp) +{ + vfio_device_set_fd(&VFIO_PCI(obj)->vbasedev, str, errp); +} +#endif + static void vfio_pci_dev_class_init(ObjectClass *klass, void *data) { DeviceClass *dc =3D DEVICE_CLASS(klass); @@ -3402,6 +3403,9 @@ static void vfio_pci_dev_class_init(ObjectClass *klas= s, void *data) =20 dc->reset =3D 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 =3D "VFIO-based PCI device assignment"; set_bit(DEVICE_CATEGORY_MISC, dc->categories); pdc->realize =3D vfio_realize; --=20 2.43.0