From patchwork Fri Sep 18 10:18:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Philippe Brucker X-Patchwork-Id: 11784603 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BBED2618 for ; Fri, 18 Sep 2020 10:23:31 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6128A208C3 for ; Fri, 18 Sep 2020 10:23:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="pEXPugyJ"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="cuyYD9o/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6128A208C3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=S/dQCpZ4VstWqyevkZKKikJHws9Wu/m2L7otXzeB6qE=; b=pEXPugyJ++9A4pz6p9NecCHHM kKtuNvdD9VjhbLauhVEiSgzw7anOdOvfDePUFacmgTnZLU9Ti2TAIUeVzIYHwcSrJZqIMK76eORQA p/hVKDk2HPEvMCpolZnGcZdlC/f6+VyBJhC1/kllElWXYe7T/xmnTevLVLmSXZ6+k52UtTzIFTiuX txfkgdORwMMRcN3LqbEGQYFge46J0oDlp7T486BB8noqOmNiTT416SF7oukYWFpl0MHYkUw0mqn3r mSiy4vgfvW3PHgMFlhcdYL/+S1+IGVJFbYVfmPzEmkuBiGH5q9oa5R0sxpRuQ6e1+s1gwfzQAabhg DE8Vlfe+Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kJDVF-0005Mv-S9; Fri, 18 Sep 2020 10:20:29 +0000 Received: from mail-ed1-x543.google.com ([2a00:1450:4864:20::543]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kJDUk-0005Ac-J5 for linux-arm-kernel@lists.infradead.org; Fri, 18 Sep 2020 10:20:02 +0000 Received: by mail-ed1-x543.google.com with SMTP id b12so5490905edz.11 for ; Fri, 18 Sep 2020 03:19:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=aqv3ZDmHKVFNAXTFaRsRnoonjs/rFQLnkFE+WBCHtmI=; b=cuyYD9o/KzC2pIYNckBzClyiRwbWWDYRG475drB7yzqFBvhSWeBm3J8FmSaGnL0/QL xR5nwdy+AoCeQX991HFvNwMNz44bp6fu5ti8Y8v2hcXqFC1lOPbND6L5oFijW/vmNOgr jkbT+FFiHBatj7ZQGuSzXJEiIhDGrrD6NyCe4fcpTtTZN5mugHhhrol7rj87jxw19KlX fAA/gWwR5rwqcGX+vONvq58dF3itVamwNTl6jzJqZ2ci+XmvsNqMQ2gAuZyp5QFswi5t 8do3FK/EEnppYoFOMH1AZv/MOSaRGF+tKntJHn6srTIge0DrFrSiIZn2eltb1H0byEiT eddg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=aqv3ZDmHKVFNAXTFaRsRnoonjs/rFQLnkFE+WBCHtmI=; b=FhLYFDe3/zyNzGVKRF87FahILKT13ukmwGpBoN8PdLZm3VdFrcLVXEnCTYLqa44Jeh NyUO5loazGzfGqMh5QwE3/oo8CTHlVr4/ES/WsDjnYaE+OwPVMIXU/aiHri78VpV2svd I4BpKgHgr57ow9sU8uZSpI2mdFXg34/y7G/p3KUbK8v7qAoXZUmeubxJvez4XmLEUlME h/d2h9jpuAzAhWtwdGkWdSRdVOjkyVhzhDWlwA7cVF3k/XOUjxEQvEX3ebeI48T5Zogx OfbWY3r1EYy3ek2R+YcJ/ObXZ5AN+eI9oJjezX1Y9e3mZOgosoHlVxfdeS5IQElD+dU8 TvHA== X-Gm-Message-State: AOAM532whMsl7bDR03Wc3lUaBikU+52atgOGNd8fmizj8DotrwWjHLki /E1BdjihmlYyWUEvOdGxeLCPzA== X-Google-Smtp-Source: ABdhPJycXf3Ue6WIV9Rxlo1kNEAhhbHclDtt1uJfQwBDseNfUhXzRCHBEOheY+S+oHqGf/+yU03vAA== X-Received: by 2002:aa7:c6cf:: with SMTP id b15mr24539435eds.134.1600424397669; Fri, 18 Sep 2020 03:19:57 -0700 (PDT) Received: from localhost.localdomain ([2001:1715:4e26:a7e0:116c:c27a:3e7f:5eaf]) by smtp.gmail.com with ESMTPSA id r16sm1940674edc.57.2020.09.18.03.19.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 18 Sep 2020 03:19:57 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org Subject: [PATCH v10 03/13] iommu/sva: Add PASID helpers Date: Fri, 18 Sep 2020 12:18:43 +0200 Message-Id: <20200918101852.582559-4-jean-philippe@linaro.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200918101852.582559-1-jean-philippe@linaro.org> References: <20200918101852.582559-1-jean-philippe@linaro.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200918_061958_703458_01FBDF63 X-CRM114-Status: GOOD ( 22.81 ) X-Spam-Score: -0.2 (/) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-0.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [2a00:1450:4864:20:0:0:0:543 listed in] [list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: fenghua.yu@intel.com, jacob.jun.pan@linux.intel.com, Jean-Philippe Brucker , catalin.marinas@arm.com, joro@8bytes.org, robin.murphy@arm.com, eric.auger@redhat.com, Jonathan.Cameron@huawei.com, zhangfei.gao@linaro.org, will@kernel.org, xuzaibo@huawei.com, baolu.lu@linux.intel.com Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Let IOMMU drivers allocate a single PASID per mm. Store the mm in the IOASID set to allow refcounting and searching mm by PASID, when handling an I/O page fault. Reviewed-by: Lu Baolu Signed-off-by: Jean-Philippe Brucker --- v10: small comment updates --- drivers/iommu/Kconfig | 5 ++ drivers/iommu/Makefile | 1 + drivers/iommu/iommu-sva-lib.h | 15 ++++++ drivers/iommu/iommu-sva-lib.c | 86 +++++++++++++++++++++++++++++++++++ 4 files changed, 107 insertions(+) create mode 100644 drivers/iommu/iommu-sva-lib.h create mode 100644 drivers/iommu/iommu-sva-lib.c diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index bef5d75e306b..fb1787377eb6 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -103,6 +103,11 @@ config IOMMU_DMA select IRQ_MSI_IOMMU select NEED_SG_DMA_LENGTH +# Shared Virtual Addressing library +config IOMMU_SVA_LIB + bool + select IOASID + config FSL_PAMU bool "Freescale IOMMU support" depends on PCI diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile index 11f1771104f3..61bd30cd8369 100644 --- a/drivers/iommu/Makefile +++ b/drivers/iommu/Makefile @@ -27,3 +27,4 @@ obj-$(CONFIG_FSL_PAMU) += fsl_pamu.o fsl_pamu_domain.o obj-$(CONFIG_S390_IOMMU) += s390-iommu.o obj-$(CONFIG_HYPERV_IOMMU) += hyperv-iommu.o obj-$(CONFIG_VIRTIO_IOMMU) += virtio-iommu.o +obj-$(CONFIG_IOMMU_SVA_LIB) += iommu-sva-lib.o diff --git a/drivers/iommu/iommu-sva-lib.h b/drivers/iommu/iommu-sva-lib.h new file mode 100644 index 000000000000..b40990aef3fd --- /dev/null +++ b/drivers/iommu/iommu-sva-lib.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * SVA library for IOMMU drivers + */ +#ifndef _IOMMU_SVA_LIB_H +#define _IOMMU_SVA_LIB_H + +#include +#include + +int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min, ioasid_t max); +void iommu_sva_free_pasid(struct mm_struct *mm); +struct mm_struct *iommu_sva_find(ioasid_t pasid); + +#endif /* _IOMMU_SVA_LIB_H */ diff --git a/drivers/iommu/iommu-sva-lib.c b/drivers/iommu/iommu-sva-lib.c new file mode 100644 index 000000000000..bd41405d34e9 --- /dev/null +++ b/drivers/iommu/iommu-sva-lib.c @@ -0,0 +1,86 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Helpers for IOMMU drivers implementing SVA + */ +#include +#include + +#include "iommu-sva-lib.h" + +static DEFINE_MUTEX(iommu_sva_lock); +static DECLARE_IOASID_SET(iommu_sva_pasid); + +/** + * iommu_sva_alloc_pasid - Allocate a PASID for the mm + * @mm: the mm + * @min: minimum PASID value (inclusive) + * @max: maximum PASID value (inclusive) + * + * Try to allocate a PASID for this mm, or take a reference to the existing one + * provided it fits within the [@min, @max] range. On success the PASID is + * available in mm->pasid, and must be released with iommu_sva_free_pasid(). + * @min must be greater than 0, because 0 indicates an unused mm->pasid. + * + * Returns 0 on success and < 0 on error. + */ +int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min, ioasid_t max) +{ + int ret = 0; + ioasid_t pasid; + + if (min == INVALID_IOASID || max == INVALID_IOASID || + min == 0 || max < min) + return -EINVAL; + + mutex_lock(&iommu_sva_lock); + if (mm->pasid) { + if (mm->pasid >= min && mm->pasid <= max) + ioasid_get(mm->pasid); + else + ret = -EOVERFLOW; + } else { + pasid = ioasid_alloc(&iommu_sva_pasid, min, max, mm); + if (pasid == INVALID_IOASID) + ret = -ENOMEM; + else + mm->pasid = pasid; + } + mutex_unlock(&iommu_sva_lock); + return ret; +} +EXPORT_SYMBOL_GPL(iommu_sva_alloc_pasid); + +/** + * iommu_sva_free_pasid - Release the mm's PASID + * @mm: the mm + * + * Drop one reference to a PASID allocated with iommu_sva_alloc_pasid() + */ +void iommu_sva_free_pasid(struct mm_struct *mm) +{ + mutex_lock(&iommu_sva_lock); + if (ioasid_put(mm->pasid)) + mm->pasid = 0; + mutex_unlock(&iommu_sva_lock); +} +EXPORT_SYMBOL_GPL(iommu_sva_free_pasid); + +/* ioasid_find getter() requires a void * argument */ +static bool __mmget_not_zero(void *mm) +{ + return mmget_not_zero(mm); +} + +/** + * iommu_sva_find() - Find mm associated to the given PASID + * @pasid: Process Address Space ID assigned to the mm + * + * On success a reference to the mm is taken, and must be released with mmput(). + * + * Returns the mm corresponding to this PASID, or an error if not found. + */ +struct mm_struct *iommu_sva_find(ioasid_t pasid) +{ + return ioasid_find(&iommu_sva_pasid, pasid, __mmget_not_zero); +} +EXPORT_SYMBOL_GPL(iommu_sva_find);