From patchwork Thu Dec 31 08:50:43 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongji Xie X-Patchwork-Id: 7935731 Return-Path: X-Original-To: patchwork-kvm@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 C2887BEEE5 for ; Thu, 31 Dec 2015 08:53:44 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id ED14520263 for ; Thu, 31 Dec 2015 08:53:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 25F4A20274 for ; Thu, 31 Dec 2015 08:53:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755420AbbLaIwW (ORCPT ); Thu, 31 Dec 2015 03:52:22 -0500 Received: from e28smtp05.in.ibm.com ([125.16.236.5]:45086 "EHLO e28smtp05.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755324AbbLaIwQ (ORCPT ); Thu, 31 Dec 2015 03:52:16 -0500 Received: from localhost by e28smtp05.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 31 Dec 2015 14:22:14 +0530 Received: from d28dlp01.in.ibm.com (9.184.220.126) by e28smtp05.in.ibm.com (192.168.1.135) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Thu, 31 Dec 2015 14:22:10 +0530 X-IBM-Helo: d28dlp01.in.ibm.com X-IBM-MailFrom: xyjxie@linux.vnet.ibm.com X-IBM-RcptTo: kvm@vger.kernel.org; linux-doc@vger.kernel.org; linux-kernel@vger.kernel.org; linux-pci@vger.kernel.org Received: from d28relay01.in.ibm.com (d28relay01.in.ibm.com [9.184.220.58]) by d28dlp01.in.ibm.com (Postfix) with ESMTP id D2221E005A; Thu, 31 Dec 2015 14:23:17 +0530 (IST) Received: from d28av03.in.ibm.com (d28av03.in.ibm.com [9.184.220.65]) by d28relay01.in.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id tBV8q95M5701910; Thu, 31 Dec 2015 14:22:09 +0530 Received: from d28av03.in.ibm.com (localhost [127.0.0.1]) by d28av03.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id tBV8q8UY027115; Thu, 31 Dec 2015 14:22:09 +0530 Received: from localhost (commit.cn.ibm.com [9.123.228.72]) by d28av03.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id tBV8q70q027085; Thu, 31 Dec 2015 14:22:07 +0530 From: Yongji Xie To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-doc@vger.kernel.org Cc: bhelgaas@google.com, corbet@lwn.net, aik@ozlabs.ru, alex.williamson@redhat.com, benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, warrier@linux.vnet.ibm.com, zhong@linux.vnet.ibm.com, nikunj@linux.vnet.ibm.com, Yongji Xie Subject: [RFC PATCH v2 2/3] vfio-pci: Allow to mmap sub-page MMIO BARs if all MMIO BARs are page aligned Date: Thu, 31 Dec 2015 16:50:43 +0800 Message-Id: <1451551844-11732-3-git-send-email-xyjxie@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1451551844-11732-1-git-send-email-xyjxie@linux.vnet.ibm.com> References: <1451551844-11732-1-git-send-email-xyjxie@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15123108-0017-0000-0000-0000093ECBBB Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham 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 Current vfio-pci implementation disallows to mmap sub-page(size < PAGE_SIZE) MMIO BARs because these BARs' mmio page may be shared with other BARs. But we should allow to mmap these sub-page MMIO BARs if PCI resource allocator enforces the alignment of all MMIO BARs to be at least PAGE_SIZE. Signed-off-by: Yongji Xie --- drivers/vfio/pci/vfio_pci.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 7e9f497..09b3805 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -552,7 +552,8 @@ static long vfio_pci_ioctl(void *device_data, VFIO_REGION_INFO_FLAG_WRITE; if (IS_ENABLED(CONFIG_VFIO_PCI_MMAP) && pci_resource_flags(pdev, info.index) & - IORESOURCE_MEM && info.size >= PAGE_SIZE) { + IORESOURCE_MEM && (info.size >= PAGE_SIZE || + pci_resource_page_aligned)) { info.flags |= VFIO_REGION_INFO_FLAG_MMAP; if (info.index == vdev->msix_bar) { ret = msix_sparse_mmap_cap(vdev, &caps); @@ -954,6 +955,10 @@ static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma) return -EINVAL; phys_len = pci_resource_len(pdev, index); + + if (pci_resource_page_aligned) + phys_len = PAGE_ALIGN(phys_len); + req_len = vma->vm_end - vma->vm_start; pgoff = vma->vm_pgoff & ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);