From patchwork Wed Aug 19 13:02:40 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Avi Kivity X-Patchwork-Id: 42603 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n7JD5LKv021571 for ; Wed, 19 Aug 2009 13:05:23 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751840AbZHSNEX (ORCPT ); Wed, 19 Aug 2009 09:04:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752082AbZHSNDe (ORCPT ); Wed, 19 Aug 2009 09:03:34 -0400 Received: from mx2.redhat.com ([66.187.237.31]:50591 "EHLO mx2.redhat.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752036AbZHSNCu (ORCPT ); Wed, 19 Aug 2009 09:02:50 -0400 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n7JD2q4C006071; Wed, 19 Aug 2009 09:02:52 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n7JD2oY3003325; Wed, 19 Aug 2009 09:02:50 -0400 Received: from cleopatra.tlv.redhat.com (cleopatra.tlv.redhat.com [10.35.255.11]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n7JD2j8D023082; Wed, 19 Aug 2009 09:02:49 -0400 Received: from localhost.localdomain (cleopatra.tlv.redhat.com [10.35.255.11]) by cleopatra.tlv.redhat.com (Postfix) with ESMTP id CFDF5250AEC; Wed, 19 Aug 2009 16:02:45 +0300 (IDT) From: Avi Kivity To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH 44/47] KVM: convert bus to slots_lock Date: Wed, 19 Aug 2009 16:02:40 +0300 Message-Id: <1250686963-8357-45-git-send-email-avi@redhat.com> In-Reply-To: <1250686963-8357-1-git-send-email-avi@redhat.com> References: <1250686963-8357-1-git-send-email-avi@redhat.com> X-Scanned-By: MIMEDefang 2.58 on 172.16.27.26 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Michael S. Tsirkin Use slots_lock to protect device list on the bus. slots_lock is already taken for read everywhere, so we only need to take it for write when registering devices. This is in preparation to removing in_range and kvm->lock around it. Signed-off-by: Michael S. Tsirkin Signed-off-by: Avi Kivity --- arch/x86/kvm/i8254.c | 5 +++-- arch/x86/kvm/i8259.c | 2 +- include/linux/kvm_host.h | 5 ++++- virt/kvm/coalesced_mmio.c | 2 +- virt/kvm/ioapic.c | 2 +- virt/kvm/kvm_main.c | 12 +++++++++++- 6 files changed, 21 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c index bcd00c7..4082cdd 100644 --- a/arch/x86/kvm/i8254.c +++ b/arch/x86/kvm/i8254.c @@ -583,6 +583,7 @@ static const struct kvm_io_device_ops speaker_dev_ops = { .in_range = speaker_in_range, }; +/* Caller must have writers lock on slots_lock */ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) { struct kvm_pit *pit; @@ -621,11 +622,11 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier); kvm_iodevice_init(&pit->dev, &pit_dev_ops); - kvm_io_bus_register_dev(&kvm->pio_bus, &pit->dev); + __kvm_io_bus_register_dev(&kvm->pio_bus, &pit->dev); if (flags & KVM_PIT_SPEAKER_DUMMY) { kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops); - kvm_io_bus_register_dev(&kvm->pio_bus, &pit->speaker_dev); + __kvm_io_bus_register_dev(&kvm->pio_bus, &pit->speaker_dev); } return pit; diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c index 148c52a..1851aec 100644 --- a/arch/x86/kvm/i8259.c +++ b/arch/x86/kvm/i8259.c @@ -548,6 +548,6 @@ struct kvm_pic *kvm_create_pic(struct kvm *kvm) * Initialize PIO device */ kvm_iodevice_init(&s->dev, &picdev_ops); - kvm_io_bus_register_dev(&kvm->pio_bus, &s->dev); + kvm_io_bus_register_dev(kvm, &kvm->pio_bus, &s->dev); return s; } diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 4ea42c9..96c8c0b 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -42,6 +42,7 @@ #define KVM_USERSPACE_IRQ_SOURCE_ID 0 +struct kvm; struct kvm_vcpu; extern struct kmem_cache *kvm_vcpu_cache; @@ -61,7 +62,9 @@ void kvm_io_bus_init(struct kvm_io_bus *bus); void kvm_io_bus_destroy(struct kvm_io_bus *bus); struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus, gpa_t addr, int len, int is_write); -void kvm_io_bus_register_dev(struct kvm_io_bus *bus, +void __kvm_io_bus_register_dev(struct kvm_io_bus *bus, + struct kvm_io_device *dev); +void kvm_io_bus_register_dev(struct kvm *kvm, struct kvm_io_bus *bus, struct kvm_io_device *dev); struct kvm_vcpu { diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c index b40946c..7b7cc9f 100644 --- a/virt/kvm/coalesced_mmio.c +++ b/virt/kvm/coalesced_mmio.c @@ -102,7 +102,7 @@ int kvm_coalesced_mmio_init(struct kvm *kvm) kvm_iodevice_init(&dev->dev, &coalesced_mmio_ops); dev->kvm = kvm; kvm->coalesced_mmio_dev = dev; - kvm_io_bus_register_dev(&kvm->mmio_bus, &dev->dev); + kvm_io_bus_register_dev(kvm, &kvm->mmio_bus, &dev->dev); return 0; } diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c index 0532fa6..0eca54e 100644 --- a/virt/kvm/ioapic.c +++ b/virt/kvm/ioapic.c @@ -343,7 +343,7 @@ int kvm_ioapic_init(struct kvm *kvm) kvm_ioapic_reset(ioapic); kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops); ioapic->kvm = kvm; - kvm_io_bus_register_dev(&kvm->mmio_bus, &ioapic->dev); + kvm_io_bus_register_dev(kvm, &kvm->mmio_bus, &ioapic->dev); return 0; } diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index bbb4029..0edc366 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2527,7 +2527,17 @@ struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus, return NULL; } -void kvm_io_bus_register_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev) +void kvm_io_bus_register_dev(struct kvm *kvm, struct kvm_io_bus *bus, + struct kvm_io_device *dev) +{ + down_write(&kvm->slots_lock); + __kvm_io_bus_register_dev(bus, dev); + up_write(&kvm->slots_lock); +} + +/* An unlocked version. Caller must have write lock on slots_lock. */ +void __kvm_io_bus_register_dev(struct kvm_io_bus *bus, + struct kvm_io_device *dev) { BUG_ON(bus->dev_count > (NR_IOBUS_DEVS-1));