From patchwork Sun Nov 23 18:35:56 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Auger X-Patchwork-Id: 5362411 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 8D7CCC11AC for ; Sun, 23 Nov 2014 18:41:15 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id AB907202A1 for ; Sun, 23 Nov 2014 18:41:14 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AD3A420274 for ; Sun, 23 Nov 2014 18:41:13 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Xsc40-0005tt-KW; Sun, 23 Nov 2014 18:39:12 +0000 Received: from mail-wi0-f171.google.com ([209.85.212.171]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Xsc2p-0005Hz-S1 for linux-arm-kernel@lists.infradead.org; Sun, 23 Nov 2014 18:38:01 +0000 Received: by mail-wi0-f171.google.com with SMTP id bs8so3707110wib.4 for ; Sun, 23 Nov 2014 10:37:38 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=9dzYUFSVMO6Kilk2we25tR14toghHSuH1ylxjvw88ts=; b=gIwtU4U3duL2svypmFdEXZ0Pm0LCe3Jk+TQAjG1qNW+73/yGsOoehQTdKKbadPIch/ PPoXoLuYh4zW9GquRd/1wZUZCs6Y8aKLs6f2nLjwy8aV2Woz/BPlGR1Ajhi7wEnpq1PG DN2HFZIZV1giovUfPlgSMUpoE1Y0HjtHHn1udMUphRnwQs37gT3S4NkyVDFp4Q4jD+3n IcYgTZeIypBKKtqJUO9PMFihnDchFmU6vV3KKcl4cTb3EuykEldgm40yKJXeoQP0y8o/ X5fYqIHKAeq+xzsOHZibvZmS8erwpXluOXEcdKjhbZ3bBNpkXswlfZYpNQaNZ2Tv9+q2 5ZLw== X-Gm-Message-State: ALoCoQlZMc2rosU5uilNpKcA73goxRfHT4IMaz2NbXbYwyY10931VjieodPyDIpYJ45Wq5fl4lHg X-Received: by 10.194.205.103 with SMTP id lf7mr26171277wjc.134.1416767858089; Sun, 23 Nov 2014 10:37:38 -0800 (PST) Received: from gnx2579.gnb.st.com (weg38-3-78-232-41-119.fbx.proxad.net. [78.232.41.119]) by mx.google.com with ESMTPSA id hk9sm17535471wjb.46.2014.11.23.10.37.35 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sun, 23 Nov 2014 10:37:37 -0800 (PST) From: Eric Auger To: eric.auger@st.com, eric.auger@linaro.org, christoffer.dall@linaro.org, marc.zyngier@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, alex.williamson@redhat.com, joel.schopp@amd.com, kim.phillips@freescale.com, paulus@samba.org, gleb@kernel.org, pbonzini@redhat.com, agraf@suse.de Subject: [PATCH v3 4/8] KVM: kvm-vfio: User API for IRQ forwarding Date: Sun, 23 Nov 2014 19:35:56 +0100 Message-Id: <1416767760-14487-5-git-send-email-eric.auger@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1416767760-14487-1-git-send-email-eric.auger@linaro.org> References: <1416767760-14487-1-git-send-email-eric.auger@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20141123_103800_103044_F6D70DF8 X-CRM114-Status: GOOD ( 17.06 ) X-Spam-Score: -0.7 (/) Cc: feng.wu@intel.com, patches@linaro.org, john.liuli@huawei.com, ming.lei@canonical.com, will.deacon@arm.com, a.rigo@virtualopensystems.com, linux-kernel@vger.kernel.org, a.motakis@virtualopensystems.com X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_LOW, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds and document a new KVM_DEV_VFIO_DEVICE group and 2 device attributes: KVM_DEV_VFIO_DEVICE_FORWARD_IRQ, KVM_DEV_VFIO_DEVICE_UNFORWARD_IRQ. The purpose is to be able to set a VFIO device IRQ as forwarded or not forwarded. the command takes as argument a handle to a new struct named kvm_arch_forwarded_irq. Signed-off-by: Eric Auger --- v2 -> v3: - rework vfio kvm device documentation - reword commit message and title - add subindex in kvm_arch_forwarded_irq to be closer to VFIO API - forwarding state can only be changed with VFIO IRQ signaling is off v1 -> v2: - struct kvm_arch_forwarded_irq moved from arch/arm/include/uapi/asm/kvm.h to include/uapi/linux/kvm.h also irq_index renamed into index and guest_irq renamed into gsi - ASSIGN/DEASSIGN renamed into FORWARD/UNFORWARD --- Documentation/virtual/kvm/devices/vfio.txt | 34 ++++++++++++++++++++++++------ include/uapi/linux/kvm.h | 10 +++++++++ 2 files changed, 38 insertions(+), 6 deletions(-) diff --git a/Documentation/virtual/kvm/devices/vfio.txt b/Documentation/virtual/kvm/devices/vfio.txt index ef51740..f7aff29 100644 --- a/Documentation/virtual/kvm/devices/vfio.txt +++ b/Documentation/virtual/kvm/devices/vfio.txt @@ -4,15 +4,24 @@ VFIO virtual device Device types supported: KVM_DEV_TYPE_VFIO -Only one VFIO instance may be created per VM. The created device -tracks VFIO groups in use by the VM and features of those groups -important to the correctness and acceleration of the VM. As groups -are enabled and disabled for use by the VM, KVM should be updated -about their presence. When registered with KVM, a reference to the -VFIO-group is held by KVM. +Only one VFIO instance may be created per VM. + +The created device tracks VFIO groups in use by the VM and features +of those groups important to the correctness and acceleration of +the VM. As groups are enabled and disabled for use by the VM, KVM +should be updated about their presence. When registered with KVM, +a reference to the VFIO-group is held by KVM. + +The device also tracks & enable VFIO device forwarded IRQs, if any. +A physical forwarded IRQ is directly completed by the guest. This +requires HW support in the interrupt controller which must be able +to automatically complete the physical IRQ when it detects the guest +has completed the corresponding virtual IRQ. The modality sometimes +is named direct EOI. Groups: KVM_DEV_VFIO_GROUP + KVM_DEV_VFIO_DEVICE KVM_DEV_VFIO_GROUP attributes: KVM_DEV_VFIO_GROUP_ADD: Add a VFIO group to VFIO-KVM device tracking @@ -20,3 +29,16 @@ KVM_DEV_VFIO_GROUP attributes: For each, kvm_device_attr.addr points to an int32_t file descriptor for the VFIO group. + +KVM_DEV_VFIO_DEVICE attributes: + KVM_DEV_VFIO_DEVICE_FORWARD_IRQ: set a VFIO device IRQ as forwarded + KVM_DEV_VFIO_DEVICE_UNFORWARD_IRQ: set a VFIO device IRQ as not forwarded + +For each, kvm_device_attr.addr points to a kvm_arch_forwarded_irq struct. + +The forwarded state can only be changed when the VFIO signaling mechanism +for this physical IRQ is not set. In other words, forwarding must be +activated before VFIO_DEVICE_SET_IRQS has been called to trigger the IRQ +or associate an eventfd to it. Unforwarding can only be called while the +signaling has been disabled with VFIO_DEVICE_SET_IRQS. If this condition is +not satisfied, the command returns an -EBUSY. diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 6076882..a269a42 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -946,6 +946,9 @@ struct kvm_device_attr { #define KVM_DEV_VFIO_GROUP 1 #define KVM_DEV_VFIO_GROUP_ADD 1 #define KVM_DEV_VFIO_GROUP_DEL 2 +#define KVM_DEV_VFIO_DEVICE 2 +#define KVM_DEV_VFIO_DEVICE_FORWARD_IRQ 1 +#define KVM_DEV_VFIO_DEVICE_UNFORWARD_IRQ 2 enum kvm_device_type { KVM_DEV_TYPE_FSL_MPIC_20 = 1, @@ -963,6 +966,13 @@ enum kvm_device_type { KVM_DEV_TYPE_MAX, }; +struct kvm_arch_forwarded_irq { + __u32 fd; /* file desciptor of the VFIO device */ + __u32 index; /* VFIO device IRQ index */ + __u32 subindex; /* VFIO device IRQ subindex */ + __u32 gsi; /* gsi, ie. virtual IRQ number */ +}; + /* * ioctls for VM fds */