From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B5110C43334 for ; Tue, 14 Jun 2022 13:09:21 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 2FB3D60B15; Tue, 14 Jun 2022 13:09:21 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id A_1mnjLwnmxk; Tue, 14 Jun 2022 13:09:20 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp3.osuosl.org (Postfix) with ESMTPS id 0CD1560AF4; Tue, 14 Jun 2022 13:09:20 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id DA536C0032; Tue, 14 Jun 2022 13:09:19 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [IPv6:2605:bc80:3010::138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 13C74C002D for ; Tue, 14 Jun 2022 13:09:18 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id E8E3282E5F for ; Tue, 14 Jun 2022 13:09:17 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id elFcE4vSY_Xm for ; Tue, 14 Jun 2022 13:09:16 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by smtp1.osuosl.org (Postfix) with ESMTPS id AAB5182A7F for ; Tue, 14 Jun 2022 13:09:15 +0000 (UTC) Received: from fraeml736-chm.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4LMpd70JCTz6F90V; Tue, 14 Jun 2022 21:07:39 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml736-chm.china.huawei.com (10.206.15.217) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 14 Jun 2022 15:09:12 +0200 Received: from [10.195.33.253] (10.195.33.253) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 14 Jun 2022 14:09:10 +0100 Message-ID: <4a3ab043-f609-22cb-895f-e67c8dd8f6ab@huawei.com> Date: Tue, 14 Jun 2022 14:12:18 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH v3 2/4] dma-iommu: Add iommu_dma_opt_mapping_size() To: , , , , , , , References: <1654507822-168026-1-git-send-email-john.garry@huawei.com> <1654507822-168026-3-git-send-email-john.garry@huawei.com> In-Reply-To: <1654507822-168026-3-git-send-email-john.garry@huawei.com> X-Originating-IP: [10.195.33.253] X-ClientProxiedBy: lhreml746-chm.china.huawei.com (10.201.108.196) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Cc: linux-scsi@vger.kernel.org, linux-doc@vger.kernel.org, liyihang6@hisilicon.com, linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, iommu@lists.linux-foundation.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: John Garry via iommu Reply-To: John Garry Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On 06/06/2022 10:30, John Garry wrote: > Add the IOMMU callback for DMA mapping API dma_opt_mapping_size(), which > allows the drivers to know the optimal mapping limit and thus limit the > requested IOVA lengths. > > This value is based on the IOVA rcache range limit, as IOVAs allocated > above this limit must always be newly allocated, which may be quite slow. > Can I please get some sort of ack from the IOMMU people on this one? Thanks, John EOM > Signed-off-by: John Garry > Reviewed-by: Damien Le Moal > --- > drivers/iommu/dma-iommu.c | 6 ++++++ > drivers/iommu/iova.c | 5 +++++ > include/linux/iova.h | 2 ++ > 3 files changed, 13 insertions(+) > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index f90251572a5d..9e1586447ee8 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -1459,6 +1459,11 @@ static unsigned long iommu_dma_get_merge_boundary(struct device *dev) > return (1UL << __ffs(domain->pgsize_bitmap)) - 1; > } > > +static size_t iommu_dma_opt_mapping_size(void) > +{ > + return iova_rcache_range(); > +} > + > static const struct dma_map_ops iommu_dma_ops = { > .alloc = iommu_dma_alloc, > .free = iommu_dma_free, > @@ -1479,6 +1484,7 @@ static const struct dma_map_ops iommu_dma_ops = { > .map_resource = iommu_dma_map_resource, > .unmap_resource = iommu_dma_unmap_resource, > .get_merge_boundary = iommu_dma_get_merge_boundary, > + .opt_mapping_size = iommu_dma_opt_mapping_size, > }; > > /* > diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c > index db77aa675145..9f00b58d546e 100644 > --- a/drivers/iommu/iova.c > +++ b/drivers/iommu/iova.c > @@ -26,6 +26,11 @@ static unsigned long iova_rcache_get(struct iova_domain *iovad, > static void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad); > static void free_iova_rcaches(struct iova_domain *iovad); > > +unsigned long iova_rcache_range(void) > +{ > + return PAGE_SIZE << (IOVA_RANGE_CACHE_MAX_SIZE - 1); > +} > + > static int iova_cpuhp_dead(unsigned int cpu, struct hlist_node *node) > { > struct iova_domain *iovad; > diff --git a/include/linux/iova.h b/include/linux/iova.h > index 320a70e40233..c6ba6d95d79c 100644 > --- a/include/linux/iova.h > +++ b/include/linux/iova.h > @@ -79,6 +79,8 @@ static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova) > int iova_cache_get(void); > void iova_cache_put(void); > > +unsigned long iova_rcache_range(void); > + > void free_iova(struct iova_domain *iovad, unsigned long pfn); > void __free_iova(struct iova_domain *iovad, struct iova *iova); > struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size, _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu