From patchwork Wed Sep 25 20:38:03 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoffer Dall X-Patchwork-Id: 2944331 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id D825D9F289 for ; Wed, 25 Sep 2013 20:38:23 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id A92BA2056A for ; Wed, 25 Sep 2013 20:38:22 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5152620565 for ; Wed, 25 Sep 2013 20:38:21 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VOvqk-0006MN-IT; Wed, 25 Sep 2013 20:38:18 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VOvqi-000620-5C; Wed, 25 Sep 2013 20:38:16 +0000 Received: from mail-pd0-f174.google.com ([209.85.192.174]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VOvqe-00061N-Kv for linux-arm-kernel@lists.infradead.org; Wed, 25 Sep 2013 20:38:13 +0000 Received: by mail-pd0-f174.google.com with SMTP id y13so175716pdi.33 for ; Wed, 25 Sep 2013 13:37:51 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-type:content-disposition:in-reply-to :user-agent; bh=q4HVZus/vVagLEP4uxdL7Cj4pt6sXd4SiRUoVRObj9g=; b=NPOVuAxKQYVx3U04HwqqwSOpXZuNcSqFGWF94tRaSIJ5ycgDsGExhvwlEnTLLVfPE2 vsHOH4AMwD2zsWMS8VGpQrZdnpM9Z0KvjfwMHCRjIPL2gC0jXLi6QWAmofgENNnQO5C9 qAK/D8mTq2iOpHbRNPlAsu4M6wYyBq0JfrmPQoFtfJTNYZgAb1F6ZEI4ufrI1d11U8aK G2xNsRss+Lmcp5ecBMUeEJFVIVNHF1C6tYBPUzLwGZnK3W+8lUEaodW4x92rLjDpzr8m 1yBOkDK9tG0B0yc4EIbZ+5NeG24YhmhFm1VtuY/hGwdfk+/3QYJDDSxzyqCiTrq9xYKk qEJA== X-Gm-Message-State: ALoCoQnqcTeXVrLuxlo3wv28wC4pXh3Cu306Se2/YsKIRZnpQi7v3vogfjqmM+zOJE2bdqbt2VKU X-Received: by 10.68.172.36 with SMTP id az4mr12082563pbc.48.1380141470970; Wed, 25 Sep 2013 13:37:50 -0700 (PDT) Received: from localhost (c-67-169-183-77.hsd1.ca.comcast.net. [67.169.183.77]) by mx.google.com with ESMTPSA id uw6sm49676426pbc.8.1969.12.31.16.00.00 (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Wed, 25 Sep 2013 13:37:50 -0700 (PDT) Date: Wed, 25 Sep 2013 13:38:03 -0700 From: Christoffer Dall To: Alexander Graf Subject: Re: [PATCH 6/8] KVM: arm-vgic: Add vgic reg access from dev attr Message-ID: <20130925203803.GF32311@cbox> References: <1377285606-15692-1-git-send-email-christoffer.dall@linaro.org> <1377285606-15692-7-git-send-email-christoffer.dall@linaro.org> <2FCDD68C-E993-4E52-AB7F-A4E5B0FB6E6F@suse.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <2FCDD68C-E993-4E52-AB7F-A4E5B0FB6E6F@suse.de> User-Agent: Mutt/1.5.21 (2010-09-15) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130925_163812_850039_AFC91806 X-CRM114-Status: GOOD ( 31.79 ) X-Spam-Score: -1.9 (-) Cc: patches@linaro.org, linaro-kernel@lists.linaro.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-6.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On Sun, Aug 25, 2013 at 04:21:58PM +0100, Alexander Graf wrote: > > On 23.08.2013, at 20:20, Christoffer Dall wrote: > > > Add infrastructure to handle distributor and cpu interface register > > accesses through the KVM_{GET/SET}_DEVICE_ATTR interface by adding the > > KVM_DEV_ARM_VGIC_GRP_DIST_REGS and KVM_DEV_ARM_VGIC_GRP_CPU_REGS groups > > and defining the semantics of the attr field to be the MMIO offset as > > specified in the GICv2 specs. > > > > Missing register accesses or other changes in individual register access > > functions to support save/restore of the VGIC state is added in > > subsequent patches. > > > > Signed-off-by: Christoffer Dall > > --- > > Documentation/virtual/kvm/devices/arm-vgic.txt | 35 ++++++ > > virt/kvm/arm/vgic.c | 143 ++++++++++++++++++++++++ > > 2 files changed, 178 insertions(+) > > > > diff --git a/Documentation/virtual/kvm/devices/arm-vgic.txt b/Documentation/virtual/kvm/devices/arm-vgic.txt > > index c9febb2..1b68475 100644 > > --- a/Documentation/virtual/kvm/devices/arm-vgic.txt > > +++ b/Documentation/virtual/kvm/devices/arm-vgic.txt > > @@ -19,3 +19,38 @@ Groups: > > KVM_VGIC_V2_ADDR_TYPE_CPU (rw, 64-bit) > > Base address in the guest physical address space of the GIC virtual cpu > > interface register mappings. > > + > > + KVM_DEV_ARM_VGIC_GRP_DIST_REGS > > + Attributes: > > + The attr field of kvm_device_attr encodes two values: > > + bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 | > > + values: | reserved | cpu id | offset | > > + > > + All distributor regs are (rw, 32-bit) > > + > > + The offset is relative to the "Distributor base address" as defined in the > > + GICv2 specs. Getting or setting such a register has the same effect as > > + reading or writing the register on the actual hardware from the cpu > > + specified with cpu id field. Note that most distributor fields are not > > + banked, but return the same value regardless of the cpu id used to access > > + the register. > > + Limitations: > > + - Priorities are not implemented, and registers are RAZ/WI > > + Errors: > > + - ENODEV: Getting or setting this register is not yet supported > > + > > + KVM_DEV_ARM_VGIC_GRP_CPU_REGS > > + Attributes: > > + The attr field of kvm_device_attr encodes two values: > > + bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 | > > + values: | reserved | cpu id | offset | > > + > > + All CPU regs are (rw, 32-bit) > > + > > + The offsetspecifies the offset from the "CPU interface base address" as > > offset specifies > > > + defined in the GICv2 specs. Getting or setting such a register has the > > + same effect as reading or writing the register on the actual hardware. > > + Limitations: > > + - Priorities are not implemented, and registers are RAZ/WI > > + Errors: > > + - ENODEV: Getting or setting this register is not yet supported > > diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c > > index 629caeb..e31625c 100644 > > --- a/virt/kvm/arm/vgic.c > > +++ b/virt/kvm/arm/vgic.c > > @@ -591,11 +591,29 @@ static bool handle_mmio_sgi_reg(struct kvm_vcpu *vcpu, > > return false; > > } > > > > +static bool handle_mmio_sgi_clear(struct kvm_vcpu *vcpu, > > + struct kvm_exit_mmio *mmio, > > + phys_addr_t offset) > > +{ > > + return false; > > +} > > + > > +static bool handle_mmio_sgi_set(struct kvm_vcpu *vcpu, > > + struct kvm_exit_mmio *mmio, > > + phys_addr_t offset) > > +{ > > + return false; > > +} > > + > > /* > > * I would have liked to use the kvm_bus_io_*() API instead, but it > > * cannot cope with banked registers (only the VM pointer is passed > > * around, and we need the vcpu). One of these days, someone please > > * fix it! > > + * > > + * Note that the handle_mmio implementations should not use the phys_addr > > + * field from the kvm_exit_mmio struct as this will not have any sane values > > + * when used to save/restore state from user space. > > */ > > struct mmio_range { > > phys_addr_t base; > > @@ -665,6 +683,16 @@ static const struct mmio_range vgic_dist_ranges[] = { > > .len = 4, > > .handle_mmio = handle_mmio_sgi_reg, > > }, > > + { > > + .base = GIC_DIST_SGI_CLEAR, > > + .len = VGIC_NR_SGIS, > > + .handle_mmio = handle_mmio_sgi_clear, > > + }, > > + { > > + .base = GIC_DIST_SGI_SET, > > + .len = VGIC_NR_SGIS, > > + .handle_mmio = handle_mmio_sgi_set, > > + }, > > {} > > }; > > > > @@ -1543,6 +1571,80 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) > > return r; > > } > > > > +static bool handle_cpu_mmio_misc(struct kvm_vcpu *vcpu, > > + struct kvm_exit_mmio *mmio, phys_addr_t offset) > > +{ > > + return true; > > +} > > + > > +static const struct mmio_range vgic_cpu_ranges[] = { > > + { > > + .base = GIC_CPU_CTRL, > > + .len = 12, > > + .handle_mmio = handle_cpu_mmio_misc, > > + }, > > + { > > + .base = GIC_CPU_ALIAS_BINPOINT, > > + .len = 4, > > + .handle_mmio = handle_cpu_mmio_misc, > > + }, > > + { > > + .base = GIC_CPU_ACTIVEPRIO, > > + .len = 16, > > + .handle_mmio = handle_cpu_mmio_misc, > > + }, > > + { > > + .base = GIC_CPU_IDENT, > > + .len = 4, > > + .handle_mmio = handle_cpu_mmio_misc, > > + }, > > +}; > > + > > +static struct kvm_exit_mmio dev_attr_mmio = { .len = 4 }; > > + > > +static int vgic_attr_regs_access(struct kvm_device *dev, > > + struct kvm_device_attr *attr, > > + u32 *reg, bool is_write) > > +{ > > + const struct mmio_range *r = NULL; > > + phys_addr_t offset; > > + int cpuid; > > + struct kvm_vcpu *vcpu; > > + struct kvm_exit_mmio mmio; > > + > > + offset = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK; > > + cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >> > > + KVM_DEV_ARM_VGIC_CPUID_SHIFT; > > + > > + if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) > > + return -EINVAL; > > + > > + vcpu = kvm_get_vcpu(dev->kvm, cpuid); > > + > > + mmio.len = 4; > > + mmio.is_write = is_write; > > + if (is_write) > > + memcpy(mmio.data, reg, sizeof(*reg)); > > Is this endianness safe? > With a big-endian kernel, no. But I suspect that breaks KVM elsewhere too. However, this is actually nicer: Thanks, -Christoffer diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index ea7fb5c..191ff9f 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1622,7 +1622,7 @@ static int vgic_attr_regs_access(struct kvm_device *dev, mmio.len = 4; mmio.is_write = is_write; if (is_write) - memcpy(mmio.data, reg, sizeof(*reg)); + mmio_data_write(mmio, ~0, *reg); if (attr->group == KVM_DEV_ARM_VGIC_GRP_DIST_REGS) r = find_matching_range(vgic_dist_ranges, &mmio, offset); @@ -1638,7 +1638,7 @@ static int vgic_attr_regs_access(struct kvm_device *dev, spin_unlock(&vcpu->kvm->arch.vgic.lock); if (!is_write) - memcpy(reg, mmio.data, sizeof(*reg)); + *reg = mmio_data_read(mmio, ~0); return 0; }