From mboxrd@z Thu Jan 1 00:00:00 1970 From: Auger Eric Subject: Re: [PATCH v7 05/17] KVM: kvm_io_bus: add kvm_io_bus_get_dev() call Date: Wed, 29 Jun 2016 17:58:52 +0200 Message-ID: <2bcfdbbb-6c63-63df-25e3-590f3867deb0@redhat.com> References: <20160628123230.26255-1-andre.przywara@arm.com> <20160628123230.26255-6-andre.przywara@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org To: Andre Przywara , Marc Zyngier , Christoffer Dall Return-path: In-Reply-To: <20160628123230.26255-6-andre.przywara@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org On 28/06/2016 14:32, Andre Przywara wrote: > The kvm_io_bus framework is a nice place of holding information about > various MMIO regions for kernel emulated devices. > Add a call to retrieve the kvm_io_device structure which is associated > with a certain MMIO address. This avoids to duplicate kvm_io_bus' > knowledge of MMIO regions without having to fake MMIO calls if a user > needs the device a certain MMIO address belongs to. > This will be used by the ITS emulation to get the associated ITS device > when someone triggers an MSI via an ioctl from userspace. > > Signed-off-by: Andre Przywara > --- > include/linux/kvm_host.h | 2 ++ > virt/kvm/kvm_main.c | 24 ++++++++++++++++++++++++ > 2 files changed, 26 insertions(+) > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index 1c9c973..c87fe6f 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -164,6 +164,8 @@ int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, > int len, struct kvm_io_device *dev); > int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, > struct kvm_io_device *dev); > +struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx, > + gpa_t addr); > > #ifdef CONFIG_KVM_ASYNC_PF > struct kvm_async_pf { > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 37af230..f6b615b9 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -3487,6 +3487,30 @@ int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, > return r; > } > > +struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx, > + gpa_t addr) > +{ > + struct kvm_io_bus *bus; > + int dev_idx, srcu_idx; > + struct kvm_io_device *iodev = NULL; > + > + srcu_idx = srcu_read_lock(&kvm->srcu); > + > + bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu); > + > + dev_idx = kvm_io_bus_get_first_dev(bus, addr, 1); > + if (dev_idx < 0) > + goto out_unlock; > + > + iodev = bus->range[dev_idx].dev; > + > +out_unlock: > + srcu_read_unlock(&kvm->srcu, srcu_idx); > + > + return iodev; > +} > +EXPORT_SYMBOL_GPL(kvm_io_bus_get_dev); > + > static struct notifier_block kvm_cpu_notifier = { > .notifier_call = kvm_cpu_hotplug, > }; > Reviewed-by: Eric Auger