From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932361Ab2HJWiC (ORCPT ); Fri, 10 Aug 2012 18:38:02 -0400 Received: from mx1.redhat.com ([209.132.183.28]:13911 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760355Ab2HJWh5 (ORCPT ); Fri, 10 Aug 2012 18:37:57 -0400 From: Alex Williamson Subject: [PATCH v8 6/6] kvm: Add de-assert option to KVM_IRQ_ACKFD To: avi@redhat.com, mst@redhat.com Cc: gleb@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Date: Fri, 10 Aug 2012 16:37:56 -0600 Message-ID: <20120810223754.809.60610.stgit@bling.home> In-Reply-To: <20120810223633.809.44188.stgit@bling.home> References: <20120810223633.809.44188.stgit@bling.home> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It's likely (vfio) that one of the reasons to watch for an IRQ ACK is to de-assert and re-enable an interrupt. As the IRQ ACK notfier is already watching a GSI for an IRQ source ID we can easily couple these together. Signed-off-by: Alex Williamson --- Documentation/virtual/kvm/api.txt | 4 ++++ arch/x86/kvm/x86.c | 1 + include/linux/kvm.h | 3 +++ virt/kvm/eventfd.c | 14 +++++++++++++- 4 files changed, 21 insertions(+), 1 deletion(-) diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 77b4837..128d4c3 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2029,6 +2029,10 @@ the eventfd is only triggered when the specified IRQ source ID is pending. On deassign, fd, gsi, and irq_source_id (if provided on assign) must be provided. +When KVM_CAP_IRQ_ACKFD_DEASSERT is available the flag +KVM_IRQ_ACKFD_FLAG_IRQ_DEASSERT may be used on assignment to specify +that the GSI should be de-asserted prior to eventfd notification. +This flag requires an IRQ source ID to be provided as described above. 5. The kvm_run structure ------------------------ diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 3d98e59..691b00d 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2178,6 +2178,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_IRQFD_ASSERT_ONLY: case KVM_CAP_IRQ_ACKFD: case KVM_CAP_IRQ_ACKFD_IRQ_SOURCE_ID: + case KVM_CAP_IRQ_ACKFD_DEASSERT: r = 1; break; case KVM_CAP_COALESCED_MMIO: diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 0f53bd5..331631e 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -623,6 +623,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_IRQFD_ASSERT_ONLY 83 #define KVM_CAP_IRQ_ACKFD 84 #define KVM_CAP_IRQ_ACKFD_IRQ_SOURCE_ID 85 +#define KVM_CAP_IRQ_ACKFD_DEASSERT 86 #ifdef KVM_CAP_IRQ_ROUTING @@ -712,6 +713,8 @@ struct kvm_irq_source_id { #define KVM_IRQ_ACKFD_FLAG_DEASSIGN (1 << 0) /* Available with KVM_CAP_IRQ_ACKFD_IRQ_SOURCE_ID */ #define KVM_IRQ_ACKFD_FLAG_IRQ_SOURCE_ID (1 << 1) +/* Available with KVM_CAP_IRQ_ACKFD_DEASSERT */ +#define KVM_IRQ_ACKFD_FLAG_DEASSERT (1 << 2) struct kvm_irq_ackfd { __u32 flags; diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c index ff5c784..ffc6a13 100644 --- a/virt/kvm/eventfd.c +++ b/virt/kvm/eventfd.c @@ -682,6 +682,7 @@ kvm_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args) struct _irq_ackfd { struct kvm *kvm; + bool deassert; /* de-assert on ack? */ struct eventfd_ctx *eventfd; /* signaled on ack */ struct kvm_irq_ack_notifier notifier; /* Setup/shutdown */ @@ -805,6 +806,10 @@ static void irq_ackfd_acked(struct kvm_irq_ack_notifier *notifier) ackfd = container_of(notifier, struct _irq_ackfd, notifier); + if (ackfd->deassert) + kvm_set_irq(ackfd->kvm, ackfd->notifier.irq_source_id, + ackfd->notifier.gsi, 0); + eventfd_signal(ackfd->eventfd, 1); } @@ -845,6 +850,12 @@ static int kvm_assign_irq_ackfd(struct kvm *kvm, struct kvm_irq_ackfd *args) ackfd->notifier.irq_source_id = -1; ackfd->notifier.irq_acked = irq_ackfd_acked; + ackfd->deassert = args->flags & KVM_IRQ_ACKFD_FLAG_DEASSERT; + if (ackfd->deassert && ackfd->notifier.irq_source_id < 0) { + ret = -EINVAL; + goto fail; + } + /* * Install our own custom wake-up handling so we are notified via * a callback whenever someone releases the underlying eventfd @@ -945,7 +956,8 @@ fail: int kvm_irq_ackfd(struct kvm *kvm, struct kvm_irq_ackfd *args) { if (args->flags & ~(KVM_IRQ_ACKFD_FLAG_DEASSIGN | - KVM_IRQ_ACKFD_FLAG_IRQ_SOURCE_ID)) + KVM_IRQ_ACKFD_FLAG_IRQ_SOURCE_ID | + KVM_IRQ_ACKFD_FLAG_DEASSERT)) return -EINVAL; if (args->flags & KVM_IRQ_ACKFD_FLAG_DEASSIGN)