From patchwork Tue Jul 19 13:11:28 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Auger X-Patchwork-Id: 9237299 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D5ABF60574 for ; Tue, 19 Jul 2016 13:13:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C6E4826A4D for ; Tue, 19 Jul 2016 13:13:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BB4CF26D08; Tue, 19 Jul 2016 13:13:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6278226A4D for ; Tue, 19 Jul 2016 13:13:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753703AbcGSNMC (ORCPT ); Tue, 19 Jul 2016 09:12:02 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40857 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753665AbcGSNMA (ORCPT ); Tue, 19 Jul 2016 09:12:00 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7C1BC3B725; Tue, 19 Jul 2016 13:11:54 +0000 (UTC) Received: from localhost.redhat.com (vpn1-4-201.ams2.redhat.com [10.36.4.201]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u6JDBbhI032501; Tue, 19 Jul 2016 09:11:49 -0400 From: Eric Auger To: eric.auger@redhat.com, eric.auger.pro@gmail.com, marc.zyngier@arm.com, christoffer.dall@linaro.org, andre.przywara@arm.com, robin.murphy@arm.com, alex.williamson@redhat.com, will.deacon@arm.com, joro@8bytes.org, tglx@linutronix.de, jason@lakedaemon.net, linux-arm-kernel@lists.infradead.org Cc: drjones@redhat.com, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, pbonzini@redhat.com, linux-kernel@vger.kernel.org, Bharat.Bhushan@freescale.com, pranav.sawargaonkar@gmail.com, p.fedin@samsung.com, iommu@lists.linux-foundation.org, Jean-Philippe.Brucker@arm.com, yehuday@marvell.com, Manish.Jaggi@caviumnetworks.com, robert.richter@caviumnetworks.com Subject: [PATCH v11 2/8] vfio/type1: vfio_find_dma accepting a type argument Date: Tue, 19 Jul 2016 13:11:28 +0000 Message-Id: <1468933894-23250-3-git-send-email-eric.auger@redhat.com> In-Reply-To: <1468933894-23250-1-git-send-email-eric.auger@redhat.com> References: <1468933894-23250-1-git-send-email-eric.auger@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Tue, 19 Jul 2016 13:11:54 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In our RB-tree we get prepared to insert slots of different types (USER and RESERVED). It becomes useful to be able to search for dma slots of a specific type or any type. This patch introduces vfio_find_dma_from_node which starts the search from a given node and stops on the first node that matches the @start and @size parameters. If this node also matches the @type parameter, the node is returned else NULL is returned. At the moment we only have USER SLOTS so the type will always match. In a separate patch, this function will be enhanced to pursue the search recursively in case a node with a different type is encountered. Signed-off-by: Eric Auger --- drivers/vfio/vfio_iommu_type1.c | 53 +++++++++++++++++++++++++++++++++-------- 1 file changed, 43 insertions(+), 10 deletions(-) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index a9f8b93..cb7267a 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -94,25 +94,56 @@ struct vfio_group { * into DMA'ble space using the IOMMU */ -static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu, - dma_addr_t start, size_t size) +/** + * vfio_find_dma_from_node: looks for a dma slot intersecting a window + * from a given rb tree node + * @top: top rb tree node where the search starts (including this node) + * @start: window start + * @size: window size + * @type: window type + */ +static struct vfio_dma *vfio_find_dma_from_node(struct rb_node *top, + dma_addr_t start, size_t size, + enum vfio_iova_type type) { - struct rb_node *node = iommu->dma_list.rb_node; + struct rb_node *node = top; + struct vfio_dma *dma; while (node) { - struct vfio_dma *dma = rb_entry(node, struct vfio_dma, node); - + dma = rb_entry(node, struct vfio_dma, node); if (start + size <= dma->iova) node = node->rb_left; else if (start >= dma->iova + dma->size) node = node->rb_right; else - return dma; + break; } + if (!node) + return NULL; + + /* a dma slot intersects our window, check the type also matches */ + if (type == VFIO_IOVA_ANY || dma->type == type) + return dma; return NULL; } +/** + * vfio_find_dma: find a dma slot intersecting a given window + * @iommu: vfio iommu handle + * @start: window base iova + * @size: window size + * @type: window type + */ +static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu, + dma_addr_t start, size_t size, + enum vfio_iova_type type) +{ + struct rb_node *top_node = iommu->dma_list.rb_node; + + return vfio_find_dma_from_node(top_node, start, size, type); +} + static void vfio_link_dma(struct vfio_iommu *iommu, struct vfio_dma *new) { struct rb_node **link = &iommu->dma_list.rb_node, *parent = NULL; @@ -484,19 +515,21 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu, * mappings within the range. */ if (iommu->v2) { - dma = vfio_find_dma(iommu, unmap->iova, 0); + dma = vfio_find_dma(iommu, unmap->iova, 0, VFIO_IOVA_USER); if (dma && dma->iova != unmap->iova) { ret = -EINVAL; goto unlock; } - dma = vfio_find_dma(iommu, unmap->iova + unmap->size - 1, 0); + dma = vfio_find_dma(iommu, unmap->iova + unmap->size - 1, 0, + VFIO_IOVA_USER); if (dma && dma->iova + dma->size != unmap->iova + unmap->size) { ret = -EINVAL; goto unlock; } } - while ((dma = vfio_find_dma(iommu, unmap->iova, unmap->size))) { + while ((dma = vfio_find_dma(iommu, unmap->iova, unmap->size, + VFIO_IOVA_USER))) { if (!iommu->v2 && unmap->iova > dma->iova) break; unmapped += dma->size; @@ -600,7 +633,7 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu, mutex_lock(&iommu->lock); - if (vfio_find_dma(iommu, iova, size)) { + if (vfio_find_dma(iommu, iova, size, VFIO_IOVA_ANY)) { mutex_unlock(&iommu->lock); return -EEXIST; }