From patchwork Thu Dec 12 19:55:41 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoffer Dall X-Patchwork-Id: 3333941 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 1F02BC0D4A for ; Thu, 12 Dec 2013 19:56:00 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0D25E2017B for ; Thu, 12 Dec 2013 19:55:59 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (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 A73242010C for ; Thu, 12 Dec 2013 19:55:57 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VrCLj-00038m-5D; Thu, 12 Dec 2013 19:55:07 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VrCLX-000889-E2; Thu, 12 Dec 2013 19:54:55 +0000 Received: from mail-pd0-f175.google.com ([209.85.192.175]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VrCLB-00082q-9H for linux-arm-kernel@lists.infradead.org; Thu, 12 Dec 2013 19:54:35 +0000 Received: by mail-pd0-f175.google.com with SMTP id w10so1080561pde.20 for ; Thu, 12 Dec 2013 11:54:11 -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=OtzKhjcm5X0tBpnZbTCZF3ZtF5j79R/rdRdOJ5VxRMs=; b=d6T7D7wf1qWXRy4dhWdrNt8xNbYro3JERz5p5/ULUXJ2gtGXnP8w2p0mghkPY6bhq5 DdpQsKSgph5iHx9W6n6eFYTF6Kzx1FvmrcpuV13D1q7YTn8LbSaZ23ujX5OS4l9Y6gki vbRUnLnG6iaG7ojinhj+exicmpwgf6s5SfHN/ZoGWKmQU3l6PzvDm93RCKbcqlQ1kiee swfti+PRFJcOPdlaA3VycYnvUj5UWWPbCOW+52wThnYQXGuSCCvpzyh5U23fG+qjWxrJ OtfqoB+M9IJwdlBBfmr9hFqYTrVuTDlZ2sUcJjlX2SdfJCxKEZ2WG6gjmQjLg/HNYT1V En0w== X-Gm-Message-State: ALoCoQmDC3Ah6/c7UCJHNHvFCTT8AHfnW53eULKaAcp0YW6wlpZpehRWxRklRgYx7mhw2iyRv713 X-Received: by 10.69.11.228 with SMTP id el4mr15327226pbd.8.1386878051833; Thu, 12 Dec 2013 11:54:11 -0800 (PST) Received: from localhost.localdomain (c-67-169-181-221.hsd1.ca.comcast.net. [67.169.181.221]) by mx.google.com with ESMTPSA id ql10sm4014884pbc.44.2013.12.12.11.54.09 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 12 Dec 2013 11:54:10 -0800 (PST) From: Christoffer Dall To: kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH 02/10] KVM: arm-vgic: Support KVM_CREATE_DEVICE for VGIC Date: Thu, 12 Dec 2013 11:55:41 -0800 Message-Id: <1386878149-13397-3-git-send-email-christoffer.dall@linaro.org> X-Mailer: git-send-email 1.8.4.3 In-Reply-To: <1386878149-13397-1-git-send-email-christoffer.dall@linaro.org> References: <1386878149-13397-1-git-send-email-christoffer.dall@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131212_145433_536409_25862279 X-CRM114-Status: GOOD ( 18.27 ) X-Spam-Score: 0.6 (/) Cc: linaro-kernel@lists.linaro.org, Christoffer Dall , patches@linaro.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 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=-1.7 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, SUSPICIOUS_RECIPS, UNPARSEABLE_RELAY autolearn=no 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 Support creating the ARM VGIC device through the KVM_CREATE_DEVICE ioctl, which can then later be leveraged to use the KVM_{GET/SET}_DEVICE_ATTR, which is useful both for setting addresses in a more generic API than the ARM-specific one and is useful for save/restore of VGIC state. Adds KVM_CAP_DEVICE_CTRL to ARM capabilities. Note that we change the check for creating a VGIC from bailing out if any VCPUs were created, to bailing out if any VCPUs were ever run. This is an important distinction that shouldn't break anything, but allows creating the VGIC after the VCPUs have been created. Signed-off-by: Christoffer Dall Acked-by: Marc Zyngier --- Changelog[v4]: - Rename kvm_arm_vgic_ops to kvm_arm_vgic_v2_ops - Add comment to kvm_vgic_create about locking vcpu->mutex Changelog[v3]: - Prevent race in kvm_vgic_create by trying to take all the vcpu locks before creating the vgic. Changelog[v2]: - None Documentation/virtual/kvm/devices/arm-vgic.txt | 10 ++++ arch/arm/kvm/arm.c | 1 + include/linux/kvm_host.h | 1 + include/uapi/linux/kvm.h | 1 + virt/kvm/arm/vgic.c | 63 +++++++++++++++++++++++++- virt/kvm/kvm_main.c | 6 ++- 6 files changed, 79 insertions(+), 3 deletions(-) create mode 100644 Documentation/virtual/kvm/devices/arm-vgic.txt diff --git a/Documentation/virtual/kvm/devices/arm-vgic.txt b/Documentation/virtual/kvm/devices/arm-vgic.txt new file mode 100644 index 0000000..38f27f7 --- /dev/null +++ b/Documentation/virtual/kvm/devices/arm-vgic.txt @@ -0,0 +1,10 @@ +ARM Virtual Generic Interrupt Controller (VGIC) +=============================================== + +Device types supported: + KVM_DEV_TYPE_ARM_VGIC_V2 ARM Generic Interrupt Controller v2.0 + +Only one VGIC instance may be instantiated through either this API or the +legacy KVM_CREATE_IRQCHIP api. The created VGIC will act as the VM interrupt +controller, requiring emulated user-space devices to inject interrupts to the +VGIC instead of directly to CPUs. diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index c9fe9d7..cc7c41a 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -190,6 +190,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_IRQCHIP: r = vgic_present; break; + case KVM_CAP_DEVICE_CTRL: case KVM_CAP_USER_MEMORY: case KVM_CAP_SYNC_MMU: case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 9523d2a..521dd76 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1076,6 +1076,7 @@ struct kvm_device *kvm_device_from_filp(struct file *filp); extern struct kvm_device_ops kvm_mpic_ops; extern struct kvm_device_ops kvm_xics_ops; extern struct kvm_device_ops kvm_vfio_ops; +extern struct kvm_device_ops kvm_arm_vgic_v2_ops; #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 902f124..b647c29 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -853,6 +853,7 @@ 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_TYPE_ARM_VGIC_V2 5 /* * ioctls for VM fds diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 5e9df47..b15d6c1 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1433,20 +1433,45 @@ out: int kvm_vgic_create(struct kvm *kvm) { - int ret = 0; + int i, vcpu_lock_idx = -1, ret = 0; + struct kvm_vcpu *vcpu; mutex_lock(&kvm->lock); - if (atomic_read(&kvm->online_vcpus) || kvm->arch.vgic.vctrl_base) { + if (kvm->arch.vgic.vctrl_base) { ret = -EEXIST; goto out; } + /* + * Any time a vcpu is run, vcpu_load is called which tries to grab the + * vcpu->mutex. By grabbing the vcpu->mutex of all VCPUs we ensure + * that no other VCPUs are run while we create the vgic. + */ + kvm_for_each_vcpu(i, vcpu, kvm) { + if (!mutex_trylock(&vcpu->mutex)) + goto out_unlock; + vcpu_lock_idx = i; + } + + kvm_for_each_vcpu(i, vcpu, kvm) { + if (vcpu->arch.has_run_once) { + ret = -EBUSY; + goto out_unlock; + } + } + spin_lock_init(&kvm->arch.vgic.lock); kvm->arch.vgic.vctrl_base = vgic_vctrl_base; kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF; kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF; +out_unlock: + for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { + vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx); + mutex_unlock(&vcpu->mutex); + } + out: mutex_unlock(&kvm->lock); return ret; @@ -1510,3 +1535,37 @@ int kvm_vgic_set_addr(struct kvm *kvm, unsigned long type, u64 addr) mutex_unlock(&kvm->lock); return r; } + +static int vgic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr) +{ + return -ENXIO; +} + +static int vgic_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr) +{ + return -ENXIO; +} + +static int vgic_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr) +{ + return -ENXIO; +} + +static void vgic_destroy(struct kvm_device *dev) +{ + kfree(dev); +} + +static int vgic_create(struct kvm_device *dev, u32 type) +{ + return kvm_vgic_create(dev->kvm); +} + +struct kvm_device_ops kvm_arm_vgic_v2_ops = { + .name = "kvm-arm-vgic", + .create = vgic_create, + .destroy = vgic_destroy, + .set_attr = vgic_set_attr, + .get_attr = vgic_get_attr, + .has_attr = vgic_has_attr, +}; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a0aa84b..954a0ba 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2279,7 +2279,11 @@ static int kvm_ioctl_create_device(struct kvm *kvm, #ifdef CONFIG_KVM_VFIO case KVM_DEV_TYPE_VFIO: ops = &kvm_vfio_ops; - break; +#endif +#ifdef CONFIG_KVM_ARM_VGIC + case KVM_DEV_TYPE_ARM_VGIC_V2: + ops = &kvm_arm_vgic_v2_ops; + break; #endif default: return -ENODEV;