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 X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 66CABC433B4 for ; Mon, 10 May 2021 14:27:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 34F30611F0 for ; Mon, 10 May 2021 14:27:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231580AbhEJO2f (ORCPT ); Mon, 10 May 2021 10:28:35 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:2677 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235260AbhEJOXq (ORCPT ); Mon, 10 May 2021 10:23:46 -0400 Received: from DGGEMS413-HUB.china.huawei.com (unknown [172.30.72.58]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4Ff39B4pCWz1BKvy; Mon, 10 May 2021 22:19:58 +0800 (CST) Received: from localhost.localdomain (10.69.192.58) by DGGEMS413-HUB.china.huawei.com (10.3.19.213) with Microsoft SMTP Server id 14.3.498.0; Mon, 10 May 2021 22:22:28 +0800 From: John Garry To: , , , , CC: , , , , , , John Garry Subject: [PATCH v2 12/15] iommu: Add iommu_set_dev_dma_opt_size() Date: Mon, 10 May 2021 22:17:26 +0800 Message-ID: <1620656249-68890-13-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 2.8.1 In-Reply-To: <1620656249-68890-1-git-send-email-john.garry@huawei.com> References: <1620656249-68890-1-git-send-email-john.garry@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.69.192.58] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a function which allows the max optimised IOMMU DMA size to be set. When set successfully, return -EPROBE_DEFER to inform the caller that the device driver needs to be reprobed to take effect. Signed-off-by: John Garry --- drivers/iommu/iommu.c | 47 +++++++++++++++++++++++++++++++++++++++++++ include/linux/iommu.h | 7 +++++++ 2 files changed, 54 insertions(+) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index bdb9aa47dfca..263d78e26c48 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -3058,6 +3058,53 @@ u32 iommu_sva_get_pasid(struct iommu_sva *handle) } EXPORT_SYMBOL_GPL(iommu_sva_get_pasid); +int iommu_set_dev_dma_opt_size(struct device *dev, size_t size) +{ + struct iommu_group *group = iommu_group_get(dev); + struct group_device *grp_dev; + struct device *_dev; + int ret, group_count; + + if (!group) + return 0; + + mutex_lock(&group->mutex); + + /* + * If already set, then ignore. We may have been set via sysfs, so + * honour that. + */ + if (group->max_opt_dma_size) { + ret = 0; + goto out; + } + + group_count = iommu_group_device_count(group); + if (group_count != 1) { + dev_err_ratelimited(dev, "Cannot change DMA opt size: Group has more than one device group_count=%d\n", + group_count); + ret = -EINVAL; + goto out; + } + + /* Since group has only one device */ + grp_dev = list_first_entry(&group->devices, struct group_device, list); + _dev = grp_dev->dev; + + if (_dev != dev) { + dev_err_ratelimited(dev, "Cannot set DMA max opt size - device has changed\n"); + ret = -EBUSY; + goto out; + } + + group->max_opt_dma_size = size; + ret = -EPROBE_DEFER; +out: + mutex_unlock(&group->mutex); + iommu_group_put(group); + return ret; +} + /* * Changes the default domain of an iommu group that has *only* one device * diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 6e187746af0f..36871e8ae636 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -428,6 +428,7 @@ extern void iommu_get_resv_regions(struct device *dev, struct list_head *list); extern void iommu_put_resv_regions(struct device *dev, struct list_head *list); extern void generic_iommu_put_resv_regions(struct device *dev, struct list_head *list); +extern int iommu_set_dev_dma_opt_size(struct device *dev, size_t size); extern void iommu_set_default_passthrough(bool cmd_line); extern void iommu_set_default_translated(bool cmd_line); extern bool iommu_default_passthrough(void); @@ -740,6 +741,12 @@ static inline int iommu_get_group_resv_regions(struct iommu_group *group, return -ENODEV; } +static inline int iommu_set_dev_dma_opt_size(struct device *dev, + size_t size) +{ + return -ENODEV; +} + static inline void iommu_set_default_passthrough(bool cmd_line) { } -- 2.26.2