From patchwork Thu Apr 18 10:39:37 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 10907005 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CD267161F for ; Thu, 18 Apr 2019 10:51:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B4E6D28C02 for ; Thu, 18 Apr 2019 10:51:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A914428C08; Thu, 18 Apr 2019 10:51:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1587928C02 for ; Thu, 18 Apr 2019 10:51:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388699AbfDRKvK (ORCPT ); Thu, 18 Apr 2019 06:51:10 -0400 Received: from 7.mo68.mail-out.ovh.net ([46.105.63.230]:41157 "EHLO 7.mo68.mail-out.ovh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388686AbfDRKvK (ORCPT ); Thu, 18 Apr 2019 06:51:10 -0400 Received: from player758.ha.ovh.net (unknown [10.109.146.86]) by mo68.mail-out.ovh.net (Postfix) with ESMTP id 9A67A11F4B3 for ; Thu, 18 Apr 2019 12:41:06 +0200 (CEST) Received: from kaod.org (lfbn-1-10649-41.w90-89.abo.wanadoo.fr [90.89.235.41]) (Authenticated sender: clg@kaod.org) by player758.ha.ovh.net (Postfix) with ESMTPSA id 4E72E4EF6A83; Thu, 18 Apr 2019 10:41:01 +0000 (UTC) From: =?utf-8?q?C=C3=A9dric_Le_Goater?= To: kvm-ppc@vger.kernel.org Cc: Paul Mackerras , David Gibson , kvm@vger.kernel.org, =?utf-8?q?C=C3=A9dric_Le_Goater?= Subject: [PATCH v6 12/17] KVM: PPC: Book3S HV: XIVE: add a TIMA mapping Date: Thu, 18 Apr 2019 12:39:37 +0200 Message-Id: <20190418103942.2883-13-clg@kaod.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190418103942.2883-1-clg@kaod.org> References: <20190418103942.2883-1-clg@kaod.org> MIME-Version: 1.0 X-Ovh-Tracer-Id: 6071415248386886615 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeduuddrfeehgddvjecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfqggfjpdevjffgvefmvefgnecuuegrihhlohhuthemucehtddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Each thread has an associated Thread Interrupt Management context composed of a set of registers. These registers let the thread handle priority management and interrupt acknowledgment. The most important are : - Interrupt Pending Buffer (IPB) - Current Processor Priority (CPPR) - Notification Source Register (NSR) They are exposed to software in four different pages each proposing a view with a different privilege. The first page is for the physical thread context and the second for the hypervisor. Only the third (operating system) and the fourth (user level) are exposed the guest. A custom VM fault handler will populate the VMA with the appropriate pages, which should only be the OS page for now. Signed-off-by: Cédric Le Goater Reviewed-by: David Gibson --- arch/powerpc/include/asm/xive.h | 1 + arch/powerpc/include/uapi/asm/kvm.h | 2 ++ arch/powerpc/kvm/book3s_xive_native.c | 39 ++++++++++++++++++++++ arch/powerpc/sysdev/xive/native.c | 11 ++++++ Documentation/virtual/kvm/devices/xive.txt | 23 +++++++++++++ 5 files changed, 76 insertions(+) diff --git a/arch/powerpc/include/asm/xive.h b/arch/powerpc/include/asm/xive.h index c4e88abd3b67..eaf76f57023a 100644 --- a/arch/powerpc/include/asm/xive.h +++ b/arch/powerpc/include/asm/xive.h @@ -23,6 +23,7 @@ * same offset regardless of where the code is executing */ extern void __iomem *xive_tima; +extern unsigned long xive_tima_os; /* * Offset in the TM area of our current execution level (provided by diff --git a/arch/powerpc/include/uapi/asm/kvm.h b/arch/powerpc/include/uapi/asm/kvm.h index cd3f16b70a2e..0998e8edc91a 100644 --- a/arch/powerpc/include/uapi/asm/kvm.h +++ b/arch/powerpc/include/uapi/asm/kvm.h @@ -720,4 +720,6 @@ struct kvm_ppc_xive_eq { #define KVM_XIVE_EQ_ALWAYS_NOTIFY 0x00000001 +#define KVM_XIVE_TIMA_PAGE_OFFSET 0 + #endif /* __LINUX_KVM_POWERPC_H */ diff --git a/arch/powerpc/kvm/book3s_xive_native.c b/arch/powerpc/kvm/book3s_xive_native.c index 2f9d5e9439a6..f5314da0cb45 100644 --- a/arch/powerpc/kvm/book3s_xive_native.c +++ b/arch/powerpc/kvm/book3s_xive_native.c @@ -165,6 +165,44 @@ int kvmppc_xive_native_connect_vcpu(struct kvm_device *dev, return rc; } +static vm_fault_t xive_native_tima_fault(struct vm_fault *vmf) +{ + struct vm_area_struct *vma = vmf->vma; + + switch (vmf->pgoff - vma->vm_pgoff) { + case 0: /* HW - forbid access */ + case 1: /* HV - forbid access */ + return VM_FAULT_SIGBUS; + case 2: /* OS */ + vmf_insert_pfn(vma, vmf->address, xive_tima_os >> PAGE_SHIFT); + return VM_FAULT_NOPAGE; + case 3: /* USER - TODO */ + default: + return VM_FAULT_SIGBUS; + } +} + +static const struct vm_operations_struct xive_native_tima_vmops = { + .fault = xive_native_tima_fault, +}; + +static int kvmppc_xive_native_mmap(struct kvm_device *dev, + struct vm_area_struct *vma) +{ + /* We only allow mappings at fixed offset for now */ + if (vma->vm_pgoff == KVM_XIVE_TIMA_PAGE_OFFSET) { + if (vma_pages(vma) > 4) + return -EINVAL; + vma->vm_ops = &xive_native_tima_vmops; + } else { + return -EINVAL; + } + + vma->vm_flags |= VM_IO | VM_PFNMAP; + vma->vm_page_prot = pgprot_noncached_wc(vma->vm_page_prot); + return 0; +} + static int kvmppc_xive_native_set_source(struct kvmppc_xive *xive, long irq, u64 addr) { @@ -1050,6 +1088,7 @@ struct kvm_device_ops kvm_xive_native_ops = { .set_attr = kvmppc_xive_native_set_attr, .get_attr = kvmppc_xive_native_get_attr, .has_attr = kvmppc_xive_native_has_attr, + .mmap = kvmppc_xive_native_mmap, }; void kvmppc_xive_native_init_module(void) diff --git a/arch/powerpc/sysdev/xive/native.c b/arch/powerpc/sysdev/xive/native.c index 0c037e933e55..7782201e5fe8 100644 --- a/arch/powerpc/sysdev/xive/native.c +++ b/arch/powerpc/sysdev/xive/native.c @@ -521,6 +521,9 @@ u32 xive_native_default_eq_shift(void) } EXPORT_SYMBOL_GPL(xive_native_default_eq_shift); +unsigned long xive_tima_os; +EXPORT_SYMBOL_GPL(xive_tima_os); + bool __init xive_native_init(void) { struct device_node *np; @@ -573,6 +576,14 @@ bool __init xive_native_init(void) for_each_possible_cpu(cpu) kvmppc_set_xive_tima(cpu, r.start, tima); + /* Resource 2 is OS window */ + if (of_address_to_resource(np, 2, &r)) { + pr_err("Failed to get thread mgmnt area resource\n"); + return false; + } + + xive_tima_os = r.start; + /* Grab size of provisionning pages */ xive_parse_provisioning(np); diff --git a/Documentation/virtual/kvm/devices/xive.txt b/Documentation/virtual/kvm/devices/xive.txt index 525d1eebcf34..0cd7847ec38a 100644 --- a/Documentation/virtual/kvm/devices/xive.txt +++ b/Documentation/virtual/kvm/devices/xive.txt @@ -13,6 +13,29 @@ requires a POWER9 host and the guest OS should have support for the XIVE native exploitation interrupt mode. If not, it should run using the legacy interrupt mode, referred as XICS (POWER7/8). +* Device Mappings + + The KVM device exposes different MMIO ranges of the XIVE HW which + are required for interrupt management. These are exposed to the + guest in VMAs populated with a custom VM fault handler. + + 1. Thread Interrupt Management Area (TIMA) + + Each thread has an associated Thread Interrupt Management context + composed of a set of registers. These registers let the thread + handle priority management and interrupt acknowledgment. The most + important are : + + - Interrupt Pending Buffer (IPB) + - Current Processor Priority (CPPR) + - Notification Source Register (NSR) + + They are exposed to software in four different pages each proposing + a view with a different privilege. The first page is for the + physical thread context and the second for the hypervisor. Only the + third (operating system) and the fourth (user level) are exposed the + guest. + * Groups: 1. KVM_DEV_XIVE_GRP_CTRL