From patchwork Fri Dec 11 08:53:13 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongji Xie X-Patchwork-Id: 7827401 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id E5B8D9F1C2 for ; Fri, 11 Dec 2015 08:56:36 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id EAF7120570 for ; Fri, 11 Dec 2015 08:56:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E90F420498 for ; Fri, 11 Dec 2015 08:56:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754467AbbLKI4S (ORCPT ); Fri, 11 Dec 2015 03:56:18 -0500 Received: from e23smtp04.au.ibm.com ([202.81.31.146]:48598 "EHLO e23smtp04.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753901AbbLKI4Q (ORCPT ); Fri, 11 Dec 2015 03:56:16 -0500 Received: from localhost by e23smtp04.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Fri, 11 Dec 2015 18:56:11 +1000 X-IBM-Helo: d23dlp01.au.ibm.com X-IBM-MailFrom: xyjxie@linux.vnet.ibm.com X-IBM-RcptTo: kvm@vger.kernel.org; linux-api@vger.kernel.org; linux-kernel@vger.kernel.org Received: from d23relay09.au.ibm.com (d23relay09.au.ibm.com [9.185.63.181]) by d23dlp01.au.ibm.com (Postfix) with ESMTP id 5E2462CE8050; Fri, 11 Dec 2015 19:56:11 +1100 (EST) Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay09.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id tBB8u3nL65667080; Fri, 11 Dec 2015 19:56:11 +1100 Received: from d23av02.au.ibm.com (localhost [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id tBB8tbok023148; Fri, 11 Dec 2015 19:55:38 +1100 Received: from localhost (commit.cn.ibm.com [9.123.229.41]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id tBB8tbcM022442; Fri, 11 Dec 2015 19:55:37 +1100 From: Yongji Xie To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Cc: 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 2/3] vfio-pci: Allow to mmap sub-page MMIO BARs if all MMIO BARs are page aligned Date: Fri, 11 Dec 2015 16:53:13 +0800 Message-Id: <1449823994-3356-3-git-send-email-xyjxie@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1449823994-3356-1-git-send-email-xyjxie@linux.vnet.ibm.com> References: <1449823994-3356-1-git-send-email-xyjxie@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15121108-0013-0000-0000-0000025A01BD 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, 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 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 all MMIO BARs are page aligned which leads the BARs' mmio page would not be shared with other BARs. This patch adds support for this case and we also add a VFIO_DEVICE_FLAGS_PCI_PAGE_ALIGNED flag to notify userspace that platform supports all MMIO BARs to be page aligned. Signed-off-by: Yongji Xie --- drivers/vfio/pci/vfio_pci.c | 10 +++++++++- drivers/vfio/pci/vfio_pci_private.h | 5 +++++ include/uapi/linux/vfio.h | 2 ++ 3 files changed, 16 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 32b88bd..dbcad99 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -443,6 +443,9 @@ static long vfio_pci_ioctl(void *device_data, if (vdev->reset_works) info.flags |= VFIO_DEVICE_FLAGS_RESET; + if (vfio_pci_bar_page_aligned()) + info.flags |= VFIO_DEVICE_FLAGS_PCI_PAGE_ALIGNED; + info.num_regions = VFIO_PCI_NUM_REGIONS; info.num_irqs = VFIO_PCI_NUM_IRQS; @@ -479,7 +482,8 @@ 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 || + vfio_pci_bar_page_aligned())) info.flags |= VFIO_REGION_INFO_FLAG_MMAP; break; case VFIO_PCI_ROM_REGION_INDEX: @@ -855,6 +859,10 @@ static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma) return -EINVAL; phys_len = pci_resource_len(pdev, index); + + if (vfio_pci_bar_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); diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h index 0e7394f..319352a 100644 --- a/drivers/vfio/pci/vfio_pci_private.h +++ b/drivers/vfio/pci/vfio_pci_private.h @@ -69,6 +69,11 @@ struct vfio_pci_device { #define is_irq_none(vdev) (!(is_intx(vdev) || is_msi(vdev) || is_msix(vdev))) #define irq_is(vdev, type) (vdev->irq_type == type) +static inline bool vfio_pci_bar_page_aligned(void) +{ + return IS_ENABLED(CONFIG_PPC64); +} + extern void vfio_pci_intx_mask(struct vfio_pci_device *vdev); extern void vfio_pci_intx_unmask(struct vfio_pci_device *vdev); diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 751b69f..1fc8066 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -171,6 +171,8 @@ struct vfio_device_info { #define VFIO_DEVICE_FLAGS_PCI (1 << 1) /* vfio-pci device */ #define VFIO_DEVICE_FLAGS_PLATFORM (1 << 2) /* vfio-platform device */ #define VFIO_DEVICE_FLAGS_AMBA (1 << 3) /* vfio-amba device */ +/* Platform support all PCI MMIO BARs to be page aligned */ +#define VFIO_DEVICE_FLAGS_PCI_PAGE_ALIGNED (1 << 4) __u32 num_regions; /* Max region index + 1 */ __u32 num_irqs; /* Max IRQ index + 1 */ };