From patchwork Mon Sep 7 15:33:58 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Grall X-Patchwork-Id: 7136831 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 1B4C1BEEC1 for ; Mon, 7 Sep 2015 15:41:47 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 3D92A20680 for ; Mon, 7 Sep 2015 15:41:46 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4554120635 for ; Mon, 7 Sep 2015 15:41:45 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZYyVp-0000wV-1A; Mon, 07 Sep 2015 15:39:17 +0000 Received: from smtp.citrix.com ([66.165.176.89]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZYyVa-0000M4-7O for linux-arm-kernel@lists.infradead.org; Mon, 07 Sep 2015 15:39:03 +0000 X-IronPort-AV: E=Sophos;i="5.17,485,1437436800"; d="scan'208";a="298262347" From: Julien Grall To: Subject: [PATCH v4 20/20] arm/xen: Add support for 64KB page granularity Date: Mon, 7 Sep 2015 16:33:58 +0100 Message-ID: <1441640038-23615-21-git-send-email-julien.grall@citrix.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1441640038-23615-1-git-send-email-julien.grall@citrix.com> References: <1441640038-23615-1-git-send-email-julien.grall@citrix.com> MIME-Version: 1.0 X-DLP: MIA1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150907_083902_503177_7DCE8BDA X-CRM114-Status: GOOD ( 12.09 ) X-Spam-Score: -6.9 (------) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Russell King , ian.campbell@citrix.com, stefano.stabellini@eu.citrix.com, linux-kernel@vger.kernel.org, Julien Grall , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_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 The hypercall interface is always using 4KB page granularity. This is requiring to use xen page definition macro when we deal with hypercall. Note that pfn_to_gfn is working with a Xen pfn (i.e 4KB). We may want to rename pfn_gfn to make this explicit. We also allocate a 64KB page for the shared page even though only the first 4KB is used. I don't think this is really important for now as it helps to have the pointer 4KB aligned (XENMEM_add_to_physmap is taking a Xen PFN). Signed-off-by: Julien Grall Reviewed-by: Stefano Stabellini --- Cc: Russell King Stefano, I've dropped your reviewed-by given I've updated the doc and do changes to avoid usage of XEN_PAGE_SHIFT Changes in v4: - Add Stefano's Reviewed-by Changes in v3: - s/MFN/GFN/ base on the new naming - Use virt_to_gfn to avoid use XEN_PAGE_SHIFT - Drop Stefano's reviewed-by - Add some docs in arch/arm/asm/xen/page.h Changes in v2 - Add Stefano's reviewed-by --- arch/arm/include/asm/xen/page.h | 15 +++++++++++++-- arch/arm/xen/enlighten.c | 6 +++--- 2 files changed, 16 insertions(+), 5 deletions(-) diff --git a/arch/arm/include/asm/xen/page.h b/arch/arm/include/asm/xen/page.h index 98c9fc3..e3d94cf 100644 --- a/arch/arm/include/asm/xen/page.h +++ b/arch/arm/include/asm/xen/page.h @@ -28,6 +28,17 @@ typedef struct xpaddr { #define INVALID_P2M_ENTRY (~0UL) +/* + * The pseudo-physical frame (pfn) used in all the helpers is always based + * on Xen page granularity (i.e 4KB). + * + * A Linux page may be split across multiple non-contiguous Xen page so we + * have to keep track with frame based on 4KB page granularity. + * + * PV drivers should never make a direct usage of those helpers (particularly + * pfn_to_gfn and gfn_to_pfn). + */ + unsigned long __pfn_to_mfn(unsigned long pfn); extern struct rb_root phys_to_mach; @@ -64,8 +75,8 @@ static inline unsigned long bfn_to_pfn(unsigned long bfn) #define bfn_to_local_pfn(bfn) bfn_to_pfn(bfn) /* VIRT <-> GUEST conversion */ -#define virt_to_gfn(v) (pfn_to_gfn(virt_to_pfn(v))) -#define gfn_to_virt(m) (__va(gfn_to_pfn(m) << PAGE_SHIFT)) +#define virt_to_gfn(v) (pfn_to_gfn(virt_to_phys(v) >> XEN_PAGE_SHIFT)) +#define gfn_to_virt(m) (__va(gfn_to_pfn(m) << XEN_PAGE_SHIFT)) /* Only used in PV code. But ARM guests are always HVM. */ static inline xmaddr_t arbitrary_virt_to_machine(void *vaddr) diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index eeeab07..50b4769 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -89,8 +89,8 @@ static void xen_percpu_init(void) pr_info("Xen: initializing cpu%d\n", cpu); vcpup = per_cpu_ptr(xen_vcpu_info, cpu); - info.mfn = __pa(vcpup) >> PAGE_SHIFT; - info.offset = offset_in_page(vcpup); + info.mfn = virt_to_gfn(vcpup); + info.offset = xen_offset_in_page(vcpup); err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info); BUG_ON(err); @@ -213,7 +213,7 @@ static int __init xen_guest_init(void) xatp.domid = DOMID_SELF; xatp.idx = 0; xatp.space = XENMAPSPACE_shared_info; - xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT; + xatp.gpfn = virt_to_gfn(shared_info_page); if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp)) BUG();