From patchwork Mon Mar 15 16:34:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Garzarella X-Patchwork-Id: 12140005 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D04E7C4332B for ; Mon, 15 Mar 2021 16:35:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A5F4E64F2A for ; Mon, 15 Mar 2021 16:35:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232386AbhCOQfQ (ORCPT ); Mon, 15 Mar 2021 12:35:16 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:46231 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232371AbhCOQfJ (ORCPT ); Mon, 15 Mar 2021 12:35:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1615826108; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=f8kPzMA8SARyFAt9L8z9nU43ZH3TNeJLbjn6RnMoeoU=; b=A5sZZzIlP3VjModfXlrK0ozBr/Nb0KtqVEPdTcN+Bvumm+bZcMtPy8JZQ7UDAZxLfuPLyU vgr83Q05aVar9KSqTTFKf3uLur+E7Qqw8cTt770P1/ztikYkawK8Zx7KmqHwQtEP8nd5mB 98S9ncbFz/dlOkNxJnUM6DYEnlVBq1g= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-504-bItcXqIMOJ2H5IdAgXMv-g-1; Mon, 15 Mar 2021 12:35:04 -0400 X-MC-Unique: bItcXqIMOJ2H5IdAgXMv-g-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id AAB5E108BD06; Mon, 15 Mar 2021 16:35:02 +0000 (UTC) Received: from steredhat.redhat.com (ovpn-114-1.ams2.redhat.com [10.36.114.1]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3A40319D7C; Mon, 15 Mar 2021 16:35:00 +0000 (UTC) From: Stefano Garzarella To: virtualization@lists.linux-foundation.org Cc: netdev@vger.kernel.org, Xie Yongji , Laurent Vivier , Stefan Hajnoczi , linux-kernel@vger.kernel.org, Max Gurtovoy , Jason Wang , Parav Pandit , "Michael S. Tsirkin" , kvm@vger.kernel.org Subject: [PATCH v4 01/14] vdpa_sim: use iova module to allocate IOVA addresses Date: Mon, 15 Mar 2021 17:34:37 +0100 Message-Id: <20210315163450.254396-2-sgarzare@redhat.com> In-Reply-To: <20210315163450.254396-1-sgarzare@redhat.com> References: <20210315163450.254396-1-sgarzare@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org The identical mapping used until now created issues when mapping different virtual pages with the same physical address. To solve this issue, we can use the iova module, to handle the IOVA allocation. For simplicity we use an IOVA allocator with byte granularity. We add two new functions, vdpasim_map_range() and vdpasim_unmap_range(), to handle the IOVA allocation and the registration into the IOMMU/IOTLB. These functions are used by dma_map_ops callbacks. Acked-by: Jason Wang Signed-off-by: Stefano Garzarella --- v2: - used ULONG_MAX instead of ~0UL [Jason] - fixed typos in comment and patch description [Jason] --- drivers/vdpa/vdpa_sim/vdpa_sim.h | 2 + drivers/vdpa/vdpa_sim/vdpa_sim.c | 108 +++++++++++++++++++------------ drivers/vdpa/Kconfig | 1 + 3 files changed, 69 insertions(+), 42 deletions(-) diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.h b/drivers/vdpa/vdpa_sim/vdpa_sim.h index 6d75444f9948..cd58e888bcf3 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.h +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h @@ -6,6 +6,7 @@ #ifndef _VDPA_SIM_H #define _VDPA_SIM_H +#include #include #include #include @@ -57,6 +58,7 @@ struct vdpasim { /* virtio config according to device type */ void *config; struct vhost_iotlb *iommu; + struct iova_domain iova; void *buffer; u32 status; u32 generation; diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c index 5b6b2f87d40c..fc2ec9599753 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c @@ -17,6 +17,7 @@ #include #include #include +#include #include "vdpa_sim.h" @@ -128,30 +129,57 @@ static int dir_to_perm(enum dma_data_direction dir) return perm; } +static dma_addr_t vdpasim_map_range(struct vdpasim *vdpasim, phys_addr_t paddr, + size_t size, unsigned int perm) +{ + struct iova *iova; + dma_addr_t dma_addr; + int ret; + + /* We set the limit_pfn to the maximum (ULONG_MAX - 1) */ + iova = alloc_iova(&vdpasim->iova, size, ULONG_MAX - 1, true); + if (!iova) + return DMA_MAPPING_ERROR; + + dma_addr = iova_dma_addr(&vdpasim->iova, iova); + + spin_lock(&vdpasim->iommu_lock); + ret = vhost_iotlb_add_range(vdpasim->iommu, (u64)dma_addr, + (u64)dma_addr + size - 1, (u64)paddr, perm); + spin_unlock(&vdpasim->iommu_lock); + + if (ret) { + __free_iova(&vdpasim->iova, iova); + return DMA_MAPPING_ERROR; + } + + return dma_addr; +} + +static void vdpasim_unmap_range(struct vdpasim *vdpasim, dma_addr_t dma_addr, + size_t size) +{ + spin_lock(&vdpasim->iommu_lock); + vhost_iotlb_del_range(vdpasim->iommu, (u64)dma_addr, + (u64)dma_addr + size - 1); + spin_unlock(&vdpasim->iommu_lock); + + free_iova(&vdpasim->iova, iova_pfn(&vdpasim->iova, dma_addr)); +} + static dma_addr_t vdpasim_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, enum dma_data_direction dir, unsigned long attrs) { struct vdpasim *vdpasim = dev_to_sim(dev); - struct vhost_iotlb *iommu = vdpasim->iommu; - u64 pa = (page_to_pfn(page) << PAGE_SHIFT) + offset; - int ret, perm = dir_to_perm(dir); + phys_addr_t paddr = page_to_phys(page) + offset; + int perm = dir_to_perm(dir); if (perm < 0) return DMA_MAPPING_ERROR; - /* For simplicity, use identical mapping to avoid e.g iova - * allocator. - */ - spin_lock(&vdpasim->iommu_lock); - ret = vhost_iotlb_add_range(iommu, pa, pa + size - 1, - pa, dir_to_perm(dir)); - spin_unlock(&vdpasim->iommu_lock); - if (ret) - return DMA_MAPPING_ERROR; - - return (dma_addr_t)(pa); + return vdpasim_map_range(vdpasim, paddr, size, perm); } static void vdpasim_unmap_page(struct device *dev, dma_addr_t dma_addr, @@ -159,12 +187,8 @@ static void vdpasim_unmap_page(struct device *dev, dma_addr_t dma_addr, unsigned long attrs) { struct vdpasim *vdpasim = dev_to_sim(dev); - struct vhost_iotlb *iommu = vdpasim->iommu; - spin_lock(&vdpasim->iommu_lock); - vhost_iotlb_del_range(iommu, (u64)dma_addr, - (u64)dma_addr + size - 1); - spin_unlock(&vdpasim->iommu_lock); + vdpasim_unmap_range(vdpasim, dma_addr, size); } static void *vdpasim_alloc_coherent(struct device *dev, size_t size, @@ -172,27 +196,22 @@ static void *vdpasim_alloc_coherent(struct device *dev, size_t size, unsigned long attrs) { struct vdpasim *vdpasim = dev_to_sim(dev); - struct vhost_iotlb *iommu = vdpasim->iommu; - void *addr = kmalloc(size, flag); - int ret; + phys_addr_t paddr; + void *addr; - spin_lock(&vdpasim->iommu_lock); + addr = kmalloc(size, flag); if (!addr) { *dma_addr = DMA_MAPPING_ERROR; - } else { - u64 pa = virt_to_phys(addr); - - ret = vhost_iotlb_add_range(iommu, (u64)pa, - (u64)pa + size - 1, - pa, VHOST_MAP_RW); - if (ret) { - *dma_addr = DMA_MAPPING_ERROR; - kfree(addr); - addr = NULL; - } else - *dma_addr = (dma_addr_t)pa; + return NULL; + } + + paddr = virt_to_phys(addr); + + *dma_addr = vdpasim_map_range(vdpasim, paddr, size, VHOST_MAP_RW); + if (*dma_addr == DMA_MAPPING_ERROR) { + kfree(addr); + return NULL; } - spin_unlock(&vdpasim->iommu_lock); return addr; } @@ -202,14 +221,10 @@ static void vdpasim_free_coherent(struct device *dev, size_t size, unsigned long attrs) { struct vdpasim *vdpasim = dev_to_sim(dev); - struct vhost_iotlb *iommu = vdpasim->iommu; - spin_lock(&vdpasim->iommu_lock); - vhost_iotlb_del_range(iommu, (u64)dma_addr, - (u64)dma_addr + size - 1); - spin_unlock(&vdpasim->iommu_lock); + vdpasim_unmap_range(vdpasim, dma_addr, size); - kfree(phys_to_virt((uintptr_t)dma_addr)); + kfree(vaddr); } static const struct dma_map_ops vdpasim_dma_ops = { @@ -271,6 +286,13 @@ struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr) for (i = 0; i < dev_attr->nvqs; i++) vringh_set_iotlb(&vdpasim->vqs[i].vring, vdpasim->iommu); + ret = iova_cache_get(); + if (ret) + goto err_iommu; + + /* For simplicity we use an IOVA allocator with byte granularity */ + init_iova_domain(&vdpasim->iova, 1, 0); + vdpasim->vdpa.dma_dev = dev; return vdpasim; @@ -541,6 +563,8 @@ static void vdpasim_free(struct vdpa_device *vdpa) struct vdpasim *vdpasim = vdpa_to_sim(vdpa); cancel_work_sync(&vdpasim->work); + put_iova_domain(&vdpasim->iova); + iova_cache_put(); kvfree(vdpasim->buffer); if (vdpasim->iommu) vhost_iotlb_free(vdpasim->iommu); diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig index a245809c99d0..6e82a0e228c2 100644 --- a/drivers/vdpa/Kconfig +++ b/drivers/vdpa/Kconfig @@ -14,6 +14,7 @@ config VDPA_SIM depends on RUNTIME_TESTING_MENU && HAS_DMA select DMA_OPS select VHOST_RING + select IOMMU_IOVA help Enable this module to support vDPA device simulators. These devices are used for testing, prototyping and development of vDPA.