From nobody Tue Apr 14 07:58:51 2026 Delivered-To: importer@patchew.org Received-SPF: none (zohomail.com: 8.43.85.245 is neither permitted nor denied by domain of lists.libvirt.org) client-ip=8.43.85.245; envelope-from=devel-bounces@lists.libvirt.org; helo=lists.libvirt.org; Authentication-Results: mx.zohomail.com; spf=none (zohomail.com: 8.43.85.245 is neither permitted nor denied by domain of lists.libvirt.org) smtp.mailfrom=devel-bounces@lists.libvirt.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.libvirt.org (lists.libvirt.org [8.43.85.245]) by mx.zohomail.com with SMTPS id 1707932972435125.52973907956823; Wed, 14 Feb 2024 09:49:32 -0800 (PST) Received: by lists.libvirt.org (Postfix, from userid 996) id 579111C0A; Wed, 14 Feb 2024 12:49:31 -0500 (EST) Received: from lists.libvirt.org.85.43.8.in-addr.arpa (localhost [IPv6:::1]) by lists.libvirt.org (Postfix) with ESMTP id D51B91B34; Wed, 14 Feb 2024 12:14:49 -0500 (EST) Received: by lists.libvirt.org (Postfix, from userid 996) id DD5131AB0; Wed, 14 Feb 2024 12:12:12 -0500 (EST) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.libvirt.org (Postfix) with ESMTPS id D87071A7E for ; Wed, 14 Feb 2024 12:11:40 -0500 (EST) Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-463-XMkbZ8WWOvGZO2cnDdAmBQ-1; Wed, 14 Feb 2024 12:11:38 -0500 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 07C1C2812FE8 for ; Wed, 14 Feb 2024 17:11:38 +0000 (UTC) Received: from harajuku.usersys.redhat.com (unknown [10.45.226.93]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 922951121337 for ; Wed, 14 Feb 2024 17:11:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on lists.libvirt.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,SPF_HELO_NONE, T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.4 X-MC-Unique: XMkbZ8WWOvGZO2cnDdAmBQ-1 From: Andrea Bolognani To: devel@lists.libvirt.org Subject: [PATCH v2 16/17] qemu: Clean up qemuDomainDefaultUSBControllerModel() Date: Wed, 14 Feb 2024 18:11:23 +0100 Message-ID: <20240214171124.508000-17-abologna@redhat.com> In-Reply-To: <20240214171124.508000-1-abologna@redhat.com> References: <20240214171124.508000-1-abologna@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.3 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Message-ID-Hash: ZJPRSTHSTRZ3UHKY5OVRZJNVDVHFBXZS X-Message-ID-Hash: ZJPRSTHSTRZ3UHKY5OVRZJNVDVHFBXZS X-MailFrom: abologna@redhat.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-config-1; header-match-config-2; header-match-config-3; header-match-devel.lists.libvirt.org-0; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; suspicious-header X-Mailman-Version: 3.2.2 Precedence: list List-Id: Development discussions about the libvirt library & tools Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: Content-Type: text/plain; charset="utf-8"; x-default="true" Content-Transfer-Encoding: quoted-printable X-ZM-MESSAGEID: 1707932973667100001 Just like qemuDomainDefaultSCSIControllerModel() before that, split the function into an internal part and a trivial public wrapper. This allows us to rewrite the internal logic in the much more compact and readable if (condition) return value; if (other_condition) return other_value; return default_value; style, while still implementing the usual error handling behavior and avoiding any ambiguity caused by VIR_DOMAIN_CONTROLLER_MODEL_USB_DEFAULT having value -1. The conversion is straightforward if messy, with one notable exception: the piix3-uhci case, which serves as our fallback, has to be moved from the top of the function to the bottom due the change from the previous set-and-overwrite approach to the new return-early approach. The use of 'else if' is eliminated completely, comments are updated and improved. Signed-off-by: Andrea Bolognani --- src/qemu/qemu_domain.c | 143 +++++++++++++++++++++++++++++------------ 1 file changed, 101 insertions(+), 42 deletions(-) diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 6801a883f4..db09af496b 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -4157,62 +4157,121 @@ qemuDomainDefaultSCSIControllerModel(virDomainCont= rollerModelSCSI *model, } =20 =20 -static int -qemuDomainDefaultUSBControllerModel(virDomainControllerModelUSB *model, - bool autoAdded, - const virDomainDef *def, - virQEMUCaps *qemuCaps, - unsigned int parseFlags) +/* Internal. Use qemuDomainDefaultUSBControllerModel() instead */ +static virDomainControllerModelUSB +qemuDomainDefaultUSBControllerModelInternal(bool autoAdded, + const virDomainDef *def, + virQEMUCaps *qemuCaps, + unsigned int parseFlags) { - /* Default USB controller is piix3-uhci if available. */ - if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_PIIX3_USB_UHCI)) - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_PIIX3_UHCI; + bool abiUpdate =3D !!(parseFlags & VIR_DOMAIN_DEF_PARSE_ABI_UPDATE); =20 if (ARCH_IS_S390(def->os.arch)) { /* No default model on s390x, one has to be provided * explicitly by the user */ - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_NONE; - } else if (ARCH_IS_PPC64(def->os.arch)) { - /* To not break migration we need to set default USB controller - * for ppc64 to pci-ohci if we cannot change ABI of the VM. - * The nec-usb-xhci or qemu-xhci controller is used as default - * only for newly defined domains or devices. */ - if ((parseFlags & VIR_DOMAIN_DEF_PARSE_ABI_UPDATE) && - virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_QEMU_XHCI)) { - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_QEMU_XHCI; - } else if ((parseFlags & VIR_DOMAIN_DEF_PARSE_ABI_UPDATE) && - virQEMUCapsGet(qemuCaps, QEMU_CAPS_NEC_USB_XHCI)) { - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_NEC_XHCI; - } else if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_PCI_OHCI)) { - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_PCI_OHCI; - } else { - /* Explicitly fallback to legacy USB controller for PPC64. */ - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_DEFAULT; - } - } else if (def->os.arch =3D=3D VIR_ARCH_AARCH64) { + return VIR_DOMAIN_CONTROLLER_MODEL_USB_NONE; + } + + if (ARCH_IS_PPC64(def->os.arch)) { + /* Newly-defined guests should use USB3 if possible */ + if (abiUpdate && virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_QEMU_XH= CI)) + return VIR_DOMAIN_CONTROLLER_MODEL_USB_QEMU_XHCI; + if (abiUpdate && virQEMUCapsGet(qemuCaps, QEMU_CAPS_NEC_USB_XHCI)) + return VIR_DOMAIN_CONTROLLER_MODEL_USB_NEC_XHCI; + + /* To preserve backwards compatibility, existing guests need to + * use pci-ohci (USB2) instead */ + if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_PCI_OHCI)) + return VIR_DOMAIN_CONTROLLER_MODEL_USB_PCI_OHCI; + + /* If neither USB3 nor USB2 can be used, bail */ + return VIR_DOMAIN_CONTROLLER_MODEL_USB_DEFAULT; + } + + if (def->os.arch =3D=3D VIR_ARCH_AARCH64) { + /* Prefer USB3 */ if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_QEMU_XHCI)) - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_QEMU_XHCI; - else if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_NEC_USB_XHCI)) - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_NEC_XHCI; + return VIR_DOMAIN_CONTROLLER_MODEL_USB_QEMU_XHCI; + if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_NEC_USB_XHCI)) + return VIR_DOMAIN_CONTROLLER_MODEL_USB_NEC_XHCI; + + /* If USB3 is unavailable, we should probably bail by + * returning VIR_DOMAIN_CONTROLLER_MODEL_USB_DEFAULT here + * instead of possibly falling back to piix3-uhci (USB1), but + * historically we haven't done that and starting now might + * cause backwards compatibility issues */ } =20 if (ARCH_IS_X86(def->os.arch)) { if (qemuDomainIsQ35(def) && autoAdded) { - /* Prefer adding a USB3 controller if supported, fall back - * to USB2 if there is no USB3 available, and if that's - * unavailable don't add anything. - */ + /* Prefer USB3 */ if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_QEMU_XHCI)) - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_QEMU_XHCI; - else if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_NEC_USB_XHCI)) - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_NEC_XHCI; - else if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_ICH9_USB_EHCI1)) - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_ICH9_EHCI1; - else - *model =3D VIR_DOMAIN_CONTROLLER_MODEL_USB_DEFAULT; + return VIR_DOMAIN_CONTROLLER_MODEL_USB_QEMU_XHCI; + if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_NEC_USB_XHCI)) + return VIR_DOMAIN_CONTROLLER_MODEL_USB_NEC_XHCI; + + /* Fall back to USB2 */ + if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_ICH9_USB_EHCI1)) + return VIR_DOMAIN_CONTROLLER_MODEL_USB_ICH9_EHCI1; + + /* If no suitable device is available, simply avoid + * adding the controller. + * + * Note that this is only the case for the USB controller + * that gets automatically added for new guests, and only + * for the q35 machine type */ + return VIR_DOMAIN_CONTROLLER_MODEL_USB_DEFAULT; } } =20 + /* The default USB controller is piix3-uhci (USB1) if available. + * This choice is a fairly poor one, rooted primarily in historical + * reasons; thankfully, in most cases we will overwrite it with a + * much more reasonable value below */ + if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_PIIX3_USB_UHCI)) + return VIR_DOMAIN_CONTROLLER_MODEL_USB_PIIX3_UHCI; + + return VIR_DOMAIN_CONTROLLER_MODEL_USB_DEFAULT; +} + + +/** + * qemuDomainDefaultUSBControllerModel: + * @model: return location + * @autoAdded: whether this controller is being automatically added + * @def: domain definition + * @cont: controller definition, or NULL + * @qemuCaps: QEMU capabilities, or NULL + * @parseFlags: parse flags + * + * Choose a reasonable model to use for a USB controller where a + * specific one hasn't been provided by the user. + * + * The choice is based on a number of factors, including the guest's + * architecture and machine type. @qemuCaps, if provided, might be + * taken into consideration too. + * + * @autoAdded should be true is this is a controller that libvirt is + * trying to automatically add on domain creation for the user's + * convenience: in that case, the function might decide that the best + * course of action is to not add the controller after all. This + * decision will be communicated to the caller by setting @model + * to VIR_DOMAIN_CONTROLLER_MODEL_USB_DEFAULT. + * + * Not being able to come up with a value is NOT considered a + * failure. It's up to the caller to decide how to handle that + * scenario. + * + * Returns: 0 on success, <0 on failure. + */ +static int +qemuDomainDefaultUSBControllerModel(virDomainControllerModelUSB *model, + bool autoAdded, + const virDomainDef *def, + virQEMUCaps *qemuCaps, + unsigned int parseFlags) +{ + *model =3D qemuDomainDefaultUSBControllerModelInternal(autoAdded, def,= qemuCaps, parseFlags); return 0; } =20 --=20 2.43.0 _______________________________________________ Devel mailing list -- devel@lists.libvirt.org To unsubscribe send an email to devel-leave@lists.libvirt.org