From nobody Fri Sep 12 03:07:59 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BF665C04A6A for ; Wed, 9 Aug 2023 12:50:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232458AbjHIMuc (ORCPT ); Wed, 9 Aug 2023 08:50:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41516 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231980AbjHIMu3 (ORCPT ); Wed, 9 Aug 2023 08:50:29 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 56D0F1FD4 for ; Wed, 9 Aug 2023 05:50:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1691585428; x=1723121428; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=fbUepnffesza+o/B0zOxYfWkMXam385Ymd7dnEQ5QDA=; b=YqXBT57n9WTe/U16OjF49JNgDafUUQWL7gfjkUIKREu/S5zST3Hom/B/ gh4XPGxDr91020AQhDu1i8rY6OoorQuUq56DpNGOt8xpq8MZIGz+vHljF Bnofyzo0hLSEPX9e5KNjKkvHnVcIg2+2B/KcHdSPSqTzR4O5Ii1afySP7 0xsTHKryddD6gjT4ShWcTJ7PXEToyfoqgDu45Nswv6W0fi4HXmjmAOSuJ j0HpX55H0hXru+ptbZaInlVx9OOiLPF5c6Bo0UCAZAopGiryVPDfdOwUS WqFp+E4aBXJLEgGWY9boOHN4GIUSi/IESD4qstO3rsRHNrrzUOwTolR/A Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10795"; a="374821676" X-IronPort-AV: E=Sophos;i="6.01,159,1684825200"; d="scan'208";a="374821676" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Aug 2023 05:50:28 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10795"; a="855521675" X-IronPort-AV: E=Sophos;i="6.01,159,1684825200"; d="scan'208";a="855521675" Received: from allen-box.sh.intel.com ([10.239.159.127]) by orsmga004.jf.intel.com with ESMTP; 09 Aug 2023 05:50:26 -0700 From: Lu Baolu To: Joerg Roedel Cc: YueHaibing , Yanfei Xu , Jacob Pan , iommu@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH 02/13] iommu: Move global PASID allocation from SVA to core Date: Wed, 9 Aug 2023 20:47:55 +0800 Message-Id: <20230809124806.45516-3-baolu.lu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230809124806.45516-1-baolu.lu@linux.intel.com> References: <20230809124806.45516-1-baolu.lu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Jacob Pan Intel ENQCMD requires a single PASID to be shared between multiple devices, as the PASID is stored in a single MSR register per-process and userspace can use only that one PASID. This means that the PASID allocation for any ENQCMD using device driver must always come from a shared global pool, regardless of what kind of domain the PASID will be used with. Split the code for the global PASID allocator into iommu_alloc/free_global_pasid() so that drivers can attach non-SVA domains to PASIDs as well. This patch moves global PASID allocation APIs from SVA to IOMMU APIs. Reserved PASIDs, currently only RID_PASID, are excluded from the global PASID allocation. It is expected that device drivers will use the allocated PASIDs to attach to appropriate IOMMU domains for use. Reviewed-by: Lu Baolu Reviewed-by: Kevin Tian Reviewed-by: Jason Gunthorpe Signed-off-by: Jacob Pan Link: https://lore.kernel.org/r/20230802212427.1497170-3-jacob.jun.pan@linu= x.intel.com Signed-off-by: Lu Baolu --- include/linux/iommu.h | 10 ++++++++++ drivers/iommu/iommu-sva.c | 29 ++++++++++------------------- drivers/iommu/iommu.c | 28 ++++++++++++++++++++++++++++ 3 files changed, 48 insertions(+), 19 deletions(-) diff --git a/include/linux/iommu.h b/include/linux/iommu.h index e71a4153041d..4cb584b08b81 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -197,6 +197,7 @@ enum iommu_dev_features { }; =20 #define IOMMU_NO_PASID (0U) /* Reserved for DMA w/o PASID */ +#define IOMMU_FIRST_GLOBAL_PASID (1U) /*starting range for allocation */ #define IOMMU_PASID_INVALID (-1U) typedef unsigned int ioasid_t; =20 @@ -733,6 +734,8 @@ void iommu_detach_device_pasid(struct iommu_domain *dom= ain, struct iommu_domain * iommu_get_domain_for_dev_pasid(struct device *dev, ioasid_t pasid, unsigned int type); +ioasid_t iommu_alloc_global_pasid(struct device *dev); +void iommu_free_global_pasid(ioasid_t pasid); #else /* CONFIG_IOMMU_API */ =20 struct iommu_ops {}; @@ -1094,6 +1097,13 @@ iommu_get_domain_for_dev_pasid(struct device *dev, i= oasid_t pasid, { return NULL; } + +static inline ioasid_t iommu_alloc_global_pasid(struct device *dev) +{ + return IOMMU_PASID_INVALID; +} + +static inline void iommu_free_global_pasid(ioasid_t pasid) {} #endif /* CONFIG_IOMMU_API */ =20 /** diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c index 05c0fb2acbc4..b78671a8a914 100644 --- a/drivers/iommu/iommu-sva.c +++ b/drivers/iommu/iommu-sva.c @@ -10,34 +10,30 @@ #include "iommu-sva.h" =20 static DEFINE_MUTEX(iommu_sva_lock); -static DEFINE_IDA(iommu_global_pasid_ida); =20 /* Allocate a PASID for the mm within range (inclusive) */ -static int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min, ioasi= d_t max) +static int iommu_sva_alloc_pasid(struct mm_struct *mm, struct device *dev) { + ioasid_t pasid; int ret =3D 0; =20 - if (min =3D=3D IOMMU_PASID_INVALID || - max =3D=3D IOMMU_PASID_INVALID || - min =3D=3D 0 || max < min) - return -EINVAL; - if (!arch_pgtable_dma_compat(mm)) return -EBUSY; =20 mutex_lock(&iommu_sva_lock); /* Is a PASID already associated with this mm? */ if (mm_valid_pasid(mm)) { - if (mm->pasid < min || mm->pasid > max) + if (mm->pasid >=3D dev->iommu->max_pasids) ret =3D -EOVERFLOW; goto out; } =20 - ret =3D ida_alloc_range(&iommu_global_pasid_ida, min, max, GFP_KERNEL); - if (ret < 0) + pasid =3D iommu_alloc_global_pasid(dev); + if (pasid =3D=3D IOMMU_PASID_INVALID) { + ret =3D -ENOSPC; goto out; - - mm->pasid =3D ret; + } + mm->pasid =3D pasid; ret =3D 0; out: mutex_unlock(&iommu_sva_lock); @@ -64,15 +60,10 @@ struct iommu_sva *iommu_sva_bind_device(struct device *= dev, struct mm_struct *mm { struct iommu_domain *domain; struct iommu_sva *handle; - ioasid_t max_pasids; int ret; =20 - max_pasids =3D dev->iommu->max_pasids; - if (!max_pasids) - return ERR_PTR(-EOPNOTSUPP); - /* Allocate mm->pasid if necessary. */ - ret =3D iommu_sva_alloc_pasid(mm, 1, max_pasids - 1); + ret =3D iommu_sva_alloc_pasid(mm, dev); if (ret) return ERR_PTR(ret); =20 @@ -217,5 +208,5 @@ void mm_pasid_drop(struct mm_struct *mm) if (likely(!mm_valid_pasid(mm))) return; =20 - ida_free(&iommu_global_pasid_ida, mm->pasid); + iommu_free_global_pasid(mm->pasid); } diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 25d7327e8013..738fee1a24f7 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -39,6 +39,7 @@ =20 static struct kset *iommu_group_kset; static DEFINE_IDA(iommu_group_ida); +static DEFINE_IDA(iommu_global_pasid_ida); =20 static unsigned int iommu_def_domain_type __read_mostly; static bool iommu_dma_strict __read_mostly =3D IS_ENABLED(CONFIG_IOMMU_DEF= AULT_DMA_STRICT); @@ -3453,3 +3454,30 @@ struct iommu_domain *iommu_sva_domain_alloc(struct d= evice *dev, =20 return domain; } + +ioasid_t iommu_alloc_global_pasid(struct device *dev) +{ + int ret; + + /* max_pasids =3D=3D 0 means that the device does not support PASID */ + if (!dev->iommu->max_pasids) + return IOMMU_PASID_INVALID; + + /* + * max_pasids is set up by vendor driver based on number of PASID bits + * supported but the IDA allocation is inclusive. + */ + ret =3D ida_alloc_range(&iommu_global_pasid_ida, IOMMU_FIRST_GLOBAL_PASID, + dev->iommu->max_pasids - 1, GFP_KERNEL); + return ret < 0 ? IOMMU_PASID_INVALID : ret; +} +EXPORT_SYMBOL_GPL(iommu_alloc_global_pasid); + +void iommu_free_global_pasid(ioasid_t pasid) +{ + if (WARN_ON(pasid =3D=3D IOMMU_PASID_INVALID)) + return; + + ida_free(&iommu_global_pasid_ida, pasid); +} +EXPORT_SYMBOL_GPL(iommu_free_global_pasid); --=20 2.34.1