From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Fedin Subject: RE: [PATCH 1/7] KVM: api: add kvm_irq_routing_extended_msi Date: Thu, 02 Jul 2015 10:26:29 +0300 Message-ID: <011f01d0b498$6a17aeb0$3e470c10$@samsung.com> References: <1435592237-17924-1-git-send-email-eric.auger@linaro.org> <1435592237-17924-2-git-send-email-eric.auger@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: pbonzini@redhat.com, linux-kernel@vger.kernel.org, patches@linaro.org To: 'Eric Auger' , eric.auger@st.com, linux-arm-kernel@lists.infradead.org, marc.zyngier@arm.com, christoffer.dall@linaro.org, andre.przywara@arm.com, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Return-path: In-reply-to: <1435592237-17924-2-git-send-email-eric.auger@linaro.org> Content-language: ru 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 Hello! > -----Original Message----- > From: kvm-owner@vger.kernel.org [mailto:kvm-owner@vger.kernel.org] On Behalf Of Eric Auger > Sent: Monday, June 29, 2015 6:37 PM > To: eric.auger@st.com; eric.auger@linaro.org; linux-arm-kernel@lists.infradead.org; > marc.zyngier@arm.com; christoffer.dall@linaro.org; andre.przywara@arm.com; > kvmarm@lists.cs.columbia.edu; kvm@vger.kernel.org > Cc: linux-kernel@vger.kernel.org; patches@linaro.org; p.fedin@samsung.com; pbonzini@redhat.com > Subject: [PATCH 1/7] KVM: api: add kvm_irq_routing_extended_msi > > On ARM, the MSI msg (address and data) comes along with > out-of-band device ID information. The device ID encodes the device > that composes the MSI msg. Let's create a new routing entry type, > dubbed KVM_IRQ_ROUTING_EXTENDED_MSI and use the __u32 pad space > to convey the device ID. > > Signed-off-by: Eric Auger > > --- > > RFC -> PATCH > - remove kvm_irq_routing_extended_msi and use union instead > --- > Documentation/virtual/kvm/api.txt | 9 ++++++++- > include/uapi/linux/kvm.h | 6 +++++- > 2 files changed, 13 insertions(+), 2 deletions(-) > > diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt > index d20fd94..6426ae9 100644 > --- a/Documentation/virtual/kvm/api.txt > +++ b/Documentation/virtual/kvm/api.txt > @@ -1414,7 +1414,10 @@ struct kvm_irq_routing_entry { > __u32 gsi; > __u32 type; > __u32 flags; > - __u32 pad; > + union { > + __u32 pad; > + __u32 devid; > + }; > union { > struct kvm_irq_routing_irqchip irqchip; > struct kvm_irq_routing_msi msi; devid is actually a part of MSI bunch. Shouldn't it be a part of struct kvm_irq_routing_msi then? It also has reserved pad. > @@ -1427,6 +1430,10 @@ struct kvm_irq_routing_entry { > #define KVM_IRQ_ROUTING_IRQCHIP 1 > #define KVM_IRQ_ROUTING_MSI 2 > #define KVM_IRQ_ROUTING_S390_ADAPTER 3 > +#define KVM_IRQ_ROUTING_EXTENDED_MSI 4 > + > +In case of KVM_IRQ_ROUTING_EXTENDED_MSI routing type, devid is used to convey > +the device ID. > > No flags are specified so far, the corresponding field must be set to zero. What if we use KVM_MSI_VALID_DEVID flag instead of new KVM_IRQ_ROUTING_EXTENDED_MSI definition? I believe this would make an API more consistent and introduce less new definitions. > > diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h > index 2a23705..8484681 100644 > --- a/include/uapi/linux/kvm.h > +++ b/include/uapi/linux/kvm.h > @@ -841,12 +841,16 @@ struct kvm_irq_routing_s390_adapter { > #define KVM_IRQ_ROUTING_IRQCHIP 1 > #define KVM_IRQ_ROUTING_MSI 2 > #define KVM_IRQ_ROUTING_S390_ADAPTER 3 > +#define KVM_IRQ_ROUTING_EXTENDED_MSI 4 > > struct kvm_irq_routing_entry { > __u32 gsi; > __u32 type; > __u32 flags; > - __u32 pad; > + union { > + __u32 pad; > + __u32 devid; > + }; > union { > struct kvm_irq_routing_irqchip irqchip; > struct kvm_irq_routing_msi msi; > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Kind regards, Pavel Fedin Expert Engineer Samsung Electronics Research center Russia