From patchwork Thu May 14 17:00:57 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Grall X-Patchwork-Id: 6408201 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 CC220C0432 for ; Thu, 14 May 2015 17:23:02 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id E48DB203E9 for ; Thu, 14 May 2015 17:23:01 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 08C0E20397 for ; Thu, 14 May 2015 17:23:01 +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 1YswnJ-0003PB-IZ; Thu, 14 May 2015 17:19:37 +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 1Yswm9-0002vF-8p for linux-arm-kernel@lists.infradead.org; Thu, 14 May 2015 17:18:27 +0000 X-IronPort-AV: E=Sophos;i="5.13,430,1427760000"; d="scan'208";a="262772825" From: Julien Grall To: Subject: [RFC 17/23] xen/grant-table: Make it running on 64KB granularity Date: Thu, 14 May 2015 18:00:57 +0100 Message-ID: <1431622863-28575-18-git-send-email-julien.grall@citrix.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1431622863-28575-1-git-send-email-julien.grall@citrix.com> References: <1431622863-28575-1-git-send-email-julien.grall@citrix.com> MIME-Version: 1.0 X-DLP: MIA2 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150514_101825_542324_7922B3C9 X-CRM114-Status: GOOD ( 13.53 ) X-Spam-Score: -5.0 (-----) Cc: Russell King , ian.campbell@citrix.com, stefano.stabellini@eu.citrix.com, Konrad Rzeszutek Wilk , tim@xen.org, linux-kernel@vger.kernel.org, Julien Grall , David Vrabel , Boris Ostrovsky , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 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=-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 Xen interface is using 4KB page granularity. This means that each grant is 4KB. The current implementation allocates a Linux page per grant. On Linux using 64KB page granularity, only the first 4KB of the page will be used. We could decrease the memory wasted by sharing the page with multiple grant. It will require some care with the {Set,Clear}ForeignPage macro. Note that no changes has been made in the x86 code because both Linux and Xen will only use 4KB page granularity. Signed-off-by: Julien Grall Cc: Stefano Stabellini Cc: Russell King Cc: Konrad Rzeszutek Wilk Cc: Boris Ostrovsky Cc: David Vrabel Reviewed-by: David Vrabel --- arch/arm/xen/p2m.c | 6 +++--- drivers/xen/grant-table.c | 6 +++--- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/arm/xen/p2m.c b/arch/arm/xen/p2m.c index 887596c..0ed01f2 100644 --- a/arch/arm/xen/p2m.c +++ b/arch/arm/xen/p2m.c @@ -93,8 +93,8 @@ int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, for (i = 0; i < count; i++) { if (map_ops[i].status) continue; - set_phys_to_machine(map_ops[i].host_addr >> PAGE_SHIFT, - map_ops[i].dev_bus_addr >> PAGE_SHIFT); + set_phys_to_machine(map_ops[i].host_addr >> XEN_PAGE_SHIFT, + map_ops[i].dev_bus_addr >> XEN_PAGE_SHIFT); } return 0; @@ -108,7 +108,7 @@ int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, int i; for (i = 0; i < count; i++) { - set_phys_to_machine(unmap_ops[i].host_addr >> PAGE_SHIFT, + set_phys_to_machine(unmap_ops[i].host_addr >> XEN_PAGE_SHIFT, INVALID_P2M_ENTRY); } diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index 62f591f..dc0a787 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -642,7 +642,7 @@ int gnttab_setup_auto_xlat_frames(phys_addr_t addr) if (xen_auto_xlat_grant_frames.count) return -EINVAL; - vaddr = xen_remap(addr, PAGE_SIZE * max_nr_gframes); + vaddr = xen_remap(addr, XEN_PAGE_SIZE * max_nr_gframes); if (vaddr == NULL) { pr_warn("Failed to ioremap gnttab share frames (addr=%pa)!\n", &addr); @@ -654,7 +654,7 @@ int gnttab_setup_auto_xlat_frames(phys_addr_t addr) return -ENOMEM; } for (i = 0; i < max_nr_gframes; i++) - pfn[i] = PFN_DOWN(addr) + i; + pfn[i] = XEN_PFN_DOWN(addr) + i; xen_auto_xlat_grant_frames.vaddr = vaddr; xen_auto_xlat_grant_frames.pfn = pfn; @@ -978,7 +978,7 @@ static void gnttab_request_version(void) { /* Only version 1 is used, which will always be available. */ grant_table_version = 1; - grefs_per_grant_frame = PAGE_SIZE / sizeof(struct grant_entry_v1); + grefs_per_grant_frame = XEN_PAGE_SIZE / sizeof(struct grant_entry_v1); gnttab_interface = &gnttab_v1_ops; pr_info("Grant tables using version %d layout\n", grant_table_version);