From patchwork Tue May 7 15:14:53 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Grall X-Patchwork-Id: 163546 Delivered-To: patch@linaro.org Received: by 2002:ac9:2a84:0:0:0:0:0 with SMTP id p4csp3883303oca; Tue, 7 May 2019 08:16:57 -0700 (PDT) X-Google-Smtp-Source: APXvYqwF04NSGriJg7CBHAGXQqdzNaT0OGlVHm/mF0e7Uc48ibOpn7LmtKrQQg6vgpSVChCD7j/y X-Received: by 2002:a24:2901:: with SMTP id p1mr13971260itp.54.1557242217785; Tue, 07 May 2019 08:16:57 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1557242217; cv=none; d=google.com; s=arc-20160816; b=ejc7mi1rg7R1/qj4nQuMKeK5rQfXYjCQ09LBlmUEv+zrfbA7WEX3w2yNUg/5qZnEXU bseNdfOCNjVb8KizqQa5KMxehRrb6ZiIDhuam9DBDlyrm4cAocll/GzyK2tQH0WPeNPo xn7hcWZpqOpHEnUWsLbSIBar8GnsXjk01qsW8Qc6eyDchCY4A4EE0D0406Q+f8Bs/J0d QHorRRHBt+a5l2G3nu/GfSNT6Fm9BelAqhgiz49GsBu+thD/qL74jetEcuVWH6K672m/ gzfMMUFt3hTyXipbSqW6fKjkfFq7QLaJ1I6jkiwPiyMwvbo8LzTOH+6d+fbeIWgyCKyR bxmQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:errors-to:content-transfer-encoding:mime-version:cc :list-subscribe:list-help:list-post:list-unsubscribe:list-id :precedence:subject:references:in-reply-to:message-id:date:to:from; bh=dFZfbLq6gj+snmjMn0yv1mvlC4grpH4NVH5RTEQOChg=; b=VmVUpOIg53B6rZvHyssEB6NztAwQGSpvYca13MskikBAjrJ0qK2mKZeovJuCMwcMJm W88FHVYJji9DtWO/YLM/6/XkFls42mBZOOcYwAGGz2lDUL2V52TFQq8n7M9fn6TtNgR8 +KHMkG1sN0rvDBiGuwP7M8m75hb+k1Lmyk4+X8eshrJAIf1DeA0Y7UTuXp0K4bbSN90g eTB8D4X1SsItiC6kRrulJaOekn4bEPVvzZBFKN3XXSQNmAXF27PJ4T26RZezhMwG2jWS NQBZBSTJgRsalDGSiHOG5ol3XyzmHCV7VdWXo3H+H1Xa3ybiO2lc+ijHEt+dNgfYOLi2 X3xQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of xen-devel-bounces@lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Return-Path: Received: from lists.xenproject.org (lists.xenproject.org. [192.237.175.120]) by mx.google.com with ESMTPS id f138si10311140itf.102.2019.05.07.08.16.57 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 07 May 2019 08:16:57 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of xen-devel-bounces@lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of xen-devel-bounces@lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hO1ob-0007Ub-7m; Tue, 07 May 2019 15:15:33 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hO1oZ-0007St-VD for xen-devel@lists.xenproject.org; Tue, 07 May 2019 15:15:31 +0000 X-Inumbo-ID: f2b693d2-70da-11e9-9688-eb272ca3a1ee Received: from foss.arm.com (unknown [217.140.101.70]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTP id f2b693d2-70da-11e9-9688-eb272ca3a1ee; Tue, 07 May 2019 15:15:29 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1F42A1688; Tue, 7 May 2019 08:15:28 -0700 (PDT) Received: from e108454-lin.cambridge.arm.com (e108454-lin.cambridge.arm.com [10.1.196.50]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D3E593F762; Tue, 7 May 2019 08:15:25 -0700 (PDT) From: Julien Grall To: xen-devel@lists.xenproject.org Date: Tue, 7 May 2019 16:14:53 +0100 Message-Id: <20190507151458.29350-10-julien.grall@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190507151458.29350-1-julien.grall@arm.com> References: <20190507151458.29350-1-julien.grall@arm.com> Subject: [Xen-devel] [PATCH 09/14] xen: Introduce HAS_M2P config and use to protect mfn_to_gmfn call X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Stefano Stabellini , Wei Liu , Konrad Rzeszutek Wilk , George Dunlap , Andrew Cooper , Ian Jackson , Tim Deegan , oleksandr_tyshchenko@epam.com, Julien Grall , Jan Beulich , andrii_anisov@epam.com, =?utf-8?q?Roger_Pau_Monn=C3=A9?= MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" While Arm never had a M2P, the implementation of mfn_to_gmfn is pretty bogus as we directly return the MFN passed in parameter. Thankfully, the use of mfn_to_gmfn is pretty limited on Arm today. There are only 3 callers: - iommu_hwdom_init: mfn_to_gmfn is used for creating IOMMU page-tables when the P2M is not shared with the IOMMU. No issues so far as Arm does not yet support non-shared P2M case. - memory_exchange: Arm cannot not use it because steal_page is not implemented. - getdomaininfo: Toolstack may map the shared page. It looks like this is mostly used for mapping the P2M of PV guest. Therefore the issue might be minor. Implementing the M2P on Arm is not planned. The M2P would require significant amount of VA address (very tough on 32-bit) that can hardly be justified with the current use of mfn_to_gmfn. - iommu_hwdom_init: mfn_to_gmfn is used because the creating of the IOMMU page-tables is delayed until the first device is assigned. In the embedded case, we will known in most of the times what devices are assigned during the domain creation. So it is possible to take to enable the IOMMU from start. See [1] for the patch. - memory_exchange: This does not work and I haven't seen any request for it so far. - getdomaininfo: The structure on Arm does not seem to contain a lot of useful information on Arm. It is unclear whether we want to allow the toolstack mapping it on Arm. This patch introduces a config option HAS_M2P to tell whether an architecture implements the M2P. - iommu_hwdom_init: For now, we require the M2P support when the IOMMU is not sharing the P2M. - memory_exchange: The hypercall is marked as not supported when the M2P does not exist. - getdomaininfo: A new helper is introduced to wrap the call to mfn_to_gfn/mfn_to_gmfn. For Arm, it returns an invalid GFN so the mapping will fail. [1] https://patchwork.kernel.org/patch/9719913/ Signed-off-by Julien Grall --- Cc: oleksandr_tyshchenko@epam.com Cc: andrii_anisov@epam.com Changes in v2: - Add a warning in public headers - Constify local variable in domain_shared_info_gfn - Invert the naming (_d / d) in domain_shared_info_gfn - Use -EOPNOTSUPP rather than -ENOSYS - Rework how the memory_exchange hypercall is removed from Arm --- xen/arch/x86/Kconfig | 1 + xen/common/Kconfig | 3 +++ xen/common/domctl.c | 2 +- xen/common/memory.c | 4 ++++ xen/drivers/passthrough/iommu.c | 6 +++++- xen/include/asm-arm/domain.h | 5 +++++ xen/include/public/domctl.h | 4 ++++ xen/include/xen/domain.h | 8 ++++++++ 8 files changed, 31 insertions(+), 2 deletions(-) diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig index 4b8b07b549..52922a87e7 100644 --- a/xen/arch/x86/Kconfig +++ b/xen/arch/x86/Kconfig @@ -16,6 +16,7 @@ config X86 select HAS_IOPORTS select HAS_KEXEC select MEM_ACCESS_ALWAYS_ON + select HAS_M2P select HAS_MEM_PAGING select HAS_MEM_SHARING select HAS_NS16550 diff --git a/xen/common/Kconfig b/xen/common/Kconfig index c838506241..df871adc8f 100644 --- a/xen/common/Kconfig +++ b/xen/common/Kconfig @@ -63,6 +63,9 @@ config HAS_GDBSX config HAS_IOPORTS bool +config HAS_M2P + bool + config NEEDS_LIBELF bool diff --git a/xen/common/domctl.c b/xen/common/domctl.c index bade9a63b1..29940fdea5 100644 --- a/xen/common/domctl.c +++ b/xen/common/domctl.c @@ -205,7 +205,7 @@ void getdomaininfo(struct domain *d, struct xen_domctl_getdomaininfo *info) info->outstanding_pages = d->outstanding_pages; info->shr_pages = atomic_read(&d->shr_pages); info->paged_pages = atomic_read(&d->paged_pages); - info->shared_info_frame = mfn_to_gmfn(d, virt_to_mfn(d->shared_info)); + info->shared_info_frame = gfn_x(domain_shared_info_gfn(d)); BUG_ON(SHARED_M2P(info->shared_info_frame)); info->cpupool = d->cpupool ? d->cpupool->cpupool_id : CPUPOOLID_NONE; diff --git a/xen/common/memory.c b/xen/common/memory.c index 86567e6117..d6a580da31 100644 --- a/xen/common/memory.c +++ b/xen/common/memory.c @@ -512,6 +512,7 @@ static bool propagate_node(unsigned int xmf, unsigned int *memflags) static long memory_exchange(XEN_GUEST_HANDLE_PARAM(xen_memory_exchange_t) arg) { +#ifdef CONFIG_M2P struct xen_memory_exchange exch; PAGE_LIST_HEAD(in_chunk_list); PAGE_LIST_HEAD(out_chunk_list); @@ -806,6 +807,9 @@ static long memory_exchange(XEN_GUEST_HANDLE_PARAM(xen_memory_exchange_t) arg) if ( __copy_field_to_guest(arg, &exch, nr_exchanged) ) rc = -EFAULT; return rc; +#else /* !CONFIG_M2P */ + return -EOPNOTSUPP; +#endif } int xenmem_add_to_physmap(struct domain *d, struct xen_add_to_physmap *xatp, diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c index a6697d58fb..dbb64b13bc 100644 --- a/xen/drivers/passthrough/iommu.c +++ b/xen/drivers/passthrough/iommu.c @@ -188,9 +188,10 @@ void __hwdom_init iommu_hwdom_init(struct domain *d) hd->need_sync = iommu_hwdom_strict && !iommu_use_hap_pt(d); if ( need_iommu_pt_sync(d) ) { + int rc = 0; +#ifdef CONFIG_HAS_M2P struct page_info *page; unsigned int i = 0, flush_flags = 0; - int rc = 0; page_list_for_each ( page, &d->page_list ) { @@ -217,6 +218,9 @@ void __hwdom_init iommu_hwdom_init(struct domain *d) /* Use while-break to avoid compiler warning */ while ( iommu_iotlb_flush_all(d, flush_flags) ) break; +#else + rc = -EOPNOTSUPP; +#endif if ( rc ) printk(XENLOG_WARNING "d%d: IOMMU mapping failed: %d\n", diff --git a/xen/include/asm-arm/domain.h b/xen/include/asm-arm/domain.h index 312fec8932..d61b0188da 100644 --- a/xen/include/asm-arm/domain.h +++ b/xen/include/asm-arm/domain.h @@ -267,6 +267,11 @@ static inline void free_vcpu_guest_context(struct vcpu_guest_context *vgc) static inline void arch_vcpu_block(struct vcpu *v) {} +static inline gfn_t domain_shared_info_gfn(struct domain *d) +{ + return INVALID_GFN; +} + #endif /* __ASM_DOMAIN_H__ */ /* diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h index 19486d5e32..cac8ffffe9 100644 --- a/xen/include/public/domctl.h +++ b/xen/include/public/domctl.h @@ -118,6 +118,10 @@ struct xen_domctl_getdomaininfo { uint64_aligned_t outstanding_pages; uint64_aligned_t shr_pages; uint64_aligned_t paged_pages; + /* + * GFN of shared_info struct. Some architectures (e.g Arm) may not + * provide a valid GFN. + */ uint64_aligned_t shared_info_frame; /* GMFN of shared_info struct */ uint64_aligned_t cpu_time; uint32_t nr_online_vcpus; /* Number of VCPUs currently online. */ diff --git a/xen/include/xen/domain.h b/xen/include/xen/domain.h index d1bfc82f57..f1761fe183 100644 --- a/xen/include/xen/domain.h +++ b/xen/include/xen/domain.h @@ -118,4 +118,12 @@ struct vnuma_info { void vnuma_destroy(struct vnuma_info *vnuma); +#ifdef CONFIG_HAS_M2P +#define domain_shared_info_gfn(d) ({ \ + const struct domain *d_ = (d); \ + \ + mfn_to_gfn(d_, _mfn(__virt_to_mfn(d_->shared_info))); \ +}) +#endif + #endif /* __XEN_DOMAIN_H__ */