Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756537Ab2BHPJR (ORCPT ); Wed, 8 Feb 2012 10:09:17 -0500 Received: from oz.csail.mit.edu ([128.30.30.239]:56113 "EHLO mail.mgebm.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755523Ab2BHPHu (ORCPT ); Wed, 8 Feb 2012 10:07:50 -0500 From: Eric B Munson To: avi@redhat.com Cc: Eric B Munson , mingo@redhat.com, hpa@zytor.com, ryanh@linux.vnet.ibm.com, aliguori@us.ibm.com, mtosatti@redhat.com, kvm@vger.kernel.org, linux-arch@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/4 V13] Add ioctl for KVM_KVMCLOCK_CTRL Date: Wed, 8 Feb 2012 10:07:45 -0500 Message-Id: <1328713666-11424-4-git-send-email-emunson@mgebm.net> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1328713666-11424-1-git-send-email-emunson@mgebm.net> References: <1328713666-11424-1-git-send-email-emunson@mgebm.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4439 Lines: 138 Now that we have a flag that will tell the guest it was suspended, create an interface for that communication using a KVM ioctl. Signed-off-by: Eric B Munson Cc: mingo@redhat.com Cc: hpa@zytor.com Cc: ryanh@linux.vnet.ibm.com Cc: aliguori@us.ibm.com Cc: mtosatti@redhat.com Cc: kvm@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org --- Changes from V12: Rename KVM_CAP and KVM ioctl Changes from V11: Correct typo in api.txt Add kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu) call to kvm_set_guest_paused() Changes from V10: Return the ioctl to per vcpu instead of per vm Changes from V9: Use kvm_for_each_vcpu to iterate online vcpu's Changes from V8: Make KVM_GUEST_PAUSED a per vm ioctl instead of per vcpu Changes from V7: Define KVM_CAP_GUEST_PAUSED and support check Call mark_page_dirty () after setting PVCLOCK_GUEST_STOPPED Changes from V4: Rename KVM_GUEST_PAUSED to KVMCLOCK_GUEST_PAUSED Add new ioctl description to api.txt Documentation/virtual/kvm/api.txt | 13 +++++++++++++ arch/x86/kvm/x86.c | 22 ++++++++++++++++++++++ include/linux/kvm.h | 3 +++ 3 files changed, 38 insertions(+), 0 deletions(-) diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 5b03eee..c6f3ac7 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -1482,6 +1482,19 @@ following algorithm: Some guests configure the LINT1 NMI input to cause a panic, aiding in debugging. +4.65 KVM_KVMCLOCK_CTRL + +Capability: KVM_CAP_KVMCLOCK_CTRL +Architectures: Any that implement pvclocks (currently x86 only) +Type: vcpu ioctl +Parameters: None +Returns: 0 on success, -1 on error + +This signals to the host kernel that the specified guest is being paused by +userspace. The host will set a flag in the pvclock structure that is checked +from the soft lockup watchdog. This ioctl can be called during pause or +unpause. + 5. The kvm_run structure Application code obtains a pointer to the kvm_run structure by diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 23c93fe..1895e4a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2050,6 +2050,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_XSAVE: case KVM_CAP_ASYNC_PF: case KVM_CAP_GET_TSC_KHZ: + case KVM_CAP_KVMCLOCK_CTRL: r = 1; break; case KVM_CAP_COALESCED_MMIO: @@ -2493,6 +2494,23 @@ static int kvm_vcpu_ioctl_x86_set_xcrs(struct kvm_vcpu *vcpu, return r; } +/* + * kvm_set_guest_paused() indicates to the guest kernel that it has been + * stopped by the hypervisor. This function will be called from the host only. + * EINVAL is returned when the host attempts to set the flag for a guest that + * does not support pv clocks. + */ +static int kvm_set_guest_paused(struct kvm_vcpu *vcpu) +{ + struct pvclock_vcpu_time_info *src = &vcpu->arch.hv_clock; + if (!vcpu->arch.time_page) + return -EINVAL; + src->flags |= PVCLOCK_GUEST_STOPPED; + mark_page_dirty(vcpu->kvm, vcpu->arch.time >> PAGE_SHIFT); + kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); + return 0; +} + long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { @@ -2782,6 +2800,10 @@ long kvm_arch_vcpu_ioctl(struct file *filp, goto out; } + case KVM_KVMCLOCK_CTRL: { + r = kvm_set_guest_paused(vcpu); + goto out; + } default: r = -EINVAL; } diff --git a/include/linux/kvm.h b/include/linux/kvm.h index c3892fc..27d5c46 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -557,6 +557,7 @@ struct kvm_ppc_pvinfo { #define KVM_CAP_MAX_VCPUS 66 /* returns max vcpus per vm */ #define KVM_CAP_PPC_PAPR 68 #define KVM_CAP_S390_GMAP 71 +#define KVM_CAP_KVMCLOCK_CTRL 72 #ifdef KVM_CAP_IRQ_ROUTING @@ -762,6 +763,8 @@ struct kvm_clock_data { #define KVM_CREATE_SPAPR_TCE _IOW(KVMIO, 0xa8, struct kvm_create_spapr_tce) /* Available with KVM_CAP_RMA */ #define KVM_ALLOCATE_RMA _IOR(KVMIO, 0xa9, struct kvm_allocate_rma) +/* VM is being stopped by host */ +#define KVM_KVMCLOCK_CTRL _IO(KVMIO, 0xaa) #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0) -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/