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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 A1673C282E1 for ; Thu, 25 Apr 2019 10:04:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7013C2064A for ; Thu, 25 Apr 2019 10:04:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730255AbfDYKEO (ORCPT ); Thu, 25 Apr 2019 06:04:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35422 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729834AbfDYKEI (ORCPT ); Thu, 25 Apr 2019 06:04:08 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8B76911DBBB; Thu, 25 Apr 2019 10:04:08 +0000 (UTC) Received: from [10.36.116.17] (ovpn-116-17.ams2.redhat.com [10.36.116.17]) by smtp.corp.redhat.com (Postfix) with ESMTPS id DFB935172F; Thu, 25 Apr 2019 10:04:02 +0000 (UTC) Subject: Re: [PATCH v2 11/19] iommu/vt-d: Replace Intel specific PASID allocator with IOASID To: Jacob Pan , iommu@lists.linux-foundation.org, LKML , Joerg Roedel , David Woodhouse , Alex Williamson , Jean-Philippe Brucker Cc: Yi Liu , "Tian, Kevin" , Raj Ashok , Christoph Hellwig , Lu Baolu , Andriy Shevchenko References: <1556062279-64135-1-git-send-email-jacob.jun.pan@linux.intel.com> <1556062279-64135-12-git-send-email-jacob.jun.pan@linux.intel.com> From: Auger Eric Message-ID: Date: Thu, 25 Apr 2019 12:04:01 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <1556062279-64135-12-git-send-email-jacob.jun.pan@linux.intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Thu, 25 Apr 2019 10:04:08 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jacob, On 4/24/19 1:31 AM, Jacob Pan wrote: > Make use of generic IOASID code to manage PASID allocation, > free, and lookup. > > Signed-off-by: Jacob Pan > --- > drivers/iommu/Kconfig | 1 + > drivers/iommu/intel-iommu.c | 9 ++++----- > drivers/iommu/intel-pasid.c | 36 ------------------------------------ > drivers/iommu/intel-svm.c | 41 ++++++++++++++++++++++++----------------- > 4 files changed, 29 insertions(+), 58 deletions(-) > > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig > index 6f07f3b..7f92009 100644 > --- a/drivers/iommu/Kconfig > +++ b/drivers/iommu/Kconfig > @@ -204,6 +204,7 @@ config INTEL_IOMMU_SVM > bool "Support for Shared Virtual Memory with Intel IOMMU" > depends on INTEL_IOMMU && X86 > select PCI_PASID > + select IOASID > select MMU_NOTIFIER > help > Shared Virtual Memory (SVM) provides a facility for devices > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c > index ec6f22d..785330a 100644 > --- a/drivers/iommu/intel-iommu.c > +++ b/drivers/iommu/intel-iommu.c > @@ -5153,7 +5153,7 @@ static void auxiliary_unlink_device(struct dmar_domain *domain, > domain->auxd_refcnt--; > > if (!domain->auxd_refcnt && domain->default_pasid > 0) > - intel_pasid_free_id(domain->default_pasid); > + ioasid_free(domain->default_pasid); > } > > static int aux_domain_add_dev(struct dmar_domain *domain, > @@ -5171,9 +5171,8 @@ static int aux_domain_add_dev(struct dmar_domain *domain, > if (domain->default_pasid <= 0) { > int pasid; > > - pasid = intel_pasid_alloc_id(domain, PASID_MIN, > - pci_max_pasids(to_pci_dev(dev)), > - GFP_KERNEL); > + pasid = ioasid_alloc(NULL, PASID_MIN, pci_max_pasids(to_pci_dev(dev)) - 1, > + domain); > if (pasid <= 0) { ioasid_t is a uint and returns INVALID_IOASID on error. Wouldn't it be simpler to make ioasid_alloc return an int? > pr_err("Can't allocate default pasid\n"); > return -ENODEV; > @@ -5210,7 +5209,7 @@ static int aux_domain_add_dev(struct dmar_domain *domain, > spin_unlock(&iommu->lock); > spin_unlock_irqrestore(&device_domain_lock, flags); > if (!domain->auxd_refcnt && domain->default_pasid > 0) > - intel_pasid_free_id(domain->default_pasid); > + ioasid_free(domain->default_pasid); > > return ret; > } > diff --git a/drivers/iommu/intel-pasid.c b/drivers/iommu/intel-pasid.c > index 5b1d3be..d339e8f 100644 > --- a/drivers/iommu/intel-pasid.c > +++ b/drivers/iommu/intel-pasid.c > @@ -26,42 +26,6 @@ > */ > static DEFINE_SPINLOCK(pasid_lock); > u32 intel_pasid_max_id = PASID_MAX; > -static DEFINE_IDR(pasid_idr); > - > -int intel_pasid_alloc_id(void *ptr, int start, int end, gfp_t gfp) > -{ > - int ret, min, max; > - > - min = max_t(int, start, PASID_MIN); > - max = min_t(int, end, intel_pasid_max_id); > - > - WARN_ON(in_interrupt()); > - idr_preload(gfp); > - spin_lock(&pasid_lock); > - ret = idr_alloc(&pasid_idr, ptr, min, max, GFP_ATOMIC); > - spin_unlock(&pasid_lock); > - idr_preload_end(); > - > - return ret; > -} > - > -void intel_pasid_free_id(int pasid) > -{ > - spin_lock(&pasid_lock); > - idr_remove(&pasid_idr, pasid); > - spin_unlock(&pasid_lock); > -} > - > -void *intel_pasid_lookup_id(int pasid) > -{ > - void *p; > - > - spin_lock(&pasid_lock); > - p = idr_find(&pasid_idr, pasid); > - spin_unlock(&pasid_lock); > - > - return p; > -} > > int vcmd_alloc_pasid(struct intel_iommu *iommu, unsigned int *pasid) > { > diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c > index 8f87304..8fff212 100644 > --- a/drivers/iommu/intel-svm.c > +++ b/drivers/iommu/intel-svm.c > @@ -25,6 +25,7 @@ > #include > #include > #include > +#include > #include > > #include "intel-pasid.h" > @@ -211,7 +212,9 @@ static void intel_mm_release(struct mmu_notifier *mn, struct mm_struct *mm) > rcu_read_lock(); > list_for_each_entry_rcu(sdev, &svm->devs, list) { > intel_pasid_tear_down_entry(svm->iommu, sdev->dev, svm->pasid); > - intel_flush_svm_range_dev(svm, sdev, 0, -1, 0, !svm->mm)> + /* for emulated iommu, PASID cache invalidation implies IOTLB/DTLB */ > + if (!cap_caching_mode(svm->iommu->cap)) > + intel_flush_svm_range_dev(svm, sdev, 0, -1, 0, !svm->mm); This change is not documented in the commit message. Isn't it a separate fix? > } > rcu_read_unlock(); > > @@ -332,16 +335,15 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_ > if (pasid_max > intel_pasid_max_id) > pasid_max = intel_pasid_max_id; > > - /* Do not use PASID 0 in caching mode (virtualised IOMMU) */ > - ret = intel_pasid_alloc_id(svm, > - !!cap_caching_mode(iommu->cap), > - pasid_max - 1, GFP_KERNEL); > - if (ret < 0) { > + /* Do not use PASID 0, reserved for RID to PASID */ > + svm->pasid = ioasid_alloc(NULL, PASID_MIN, > + pasid_max - 1, svm); the fact the max is not decremented compared to intel_pasid_alloc_id looks suspicious to me (exclusive to inclusive move). I guess it is a fix in which case this may be documented in the commit msg? > + if (svm->pasid == INVALID_IOASID) { > kfree(svm); > kfree(sdev); > + ret = ENOSPC; -ENOSPC > goto out; > } > - svm->pasid = ret; > svm->notifier.ops = &intel_mmuops; > svm->mm = mm; > svm->flags = flags; > @@ -351,7 +353,7 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_ > if (mm) { > ret = mmu_notifier_register(&svm->notifier, mm); > if (ret) { > - intel_pasid_free_id(svm->pasid); > + ioasid_free(svm->pasid); > kfree(svm); > kfree(sdev); > goto out; > @@ -367,7 +369,7 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_ > if (ret) { > if (mm) > mmu_notifier_unregister(&svm->notifier, mm); > - intel_pasid_free_id(svm->pasid); > + ioasid_free(svm->pasid); the ioasid_free returned value never is tested. Is it useful? > kfree(svm); > kfree(sdev); > goto out; > @@ -400,7 +402,12 @@ int intel_svm_unbind_mm(struct device *dev, int pasid) > if (!iommu) > goto out; > > - svm = intel_pasid_lookup_id(pasid); > + svm = ioasid_find(NULL, pasid, NULL); > + if (IS_ERR(svm)) { > + ret = PTR_ERR(svm); > + goto out; > + } > + > if (!svm) > goto out; > > @@ -422,7 +429,7 @@ int intel_svm_unbind_mm(struct device *dev, int pasid) > kfree_rcu(sdev, rcu); > > if (list_empty(&svm->devs)) { > - intel_pasid_free_id(svm->pasid); > + ioasid_free(svm->pasid); > if (svm->mm) > mmu_notifier_unregister(&svm->notifier, svm->mm); > > @@ -457,10 +464,11 @@ int intel_svm_is_pasid_valid(struct device *dev, int pasid) > if (!iommu) > goto out; > > - svm = intel_pasid_lookup_id(pasid); > - if (!svm) > + svm = ioasid_find(NULL, pasid, NULL); > + if (IS_ERR(svm)) { > + ret = PTR_ERR(svm); > goto out; > - > + } > /* init_mm is used in this case */ > if (!svm->mm) > ret = 1; > @@ -567,13 +575,12 @@ static irqreturn_t prq_event_thread(int irq, void *d) > > if (!svm || svm->pasid != req->pasid) { > rcu_read_lock(); > - svm = intel_pasid_lookup_id(req->pasid); > + svm = ioasid_find(NULL, req->pasid, NULL); > /* It *can't* go away, because the driver is not permitted > * to unbind the mm while any page faults are outstanding. > * So we only need RCU to protect the internal idr code. */ > rcu_read_unlock(); > - > - if (!svm) { > + if (IS_ERR(svm) || !svm) { > pr_err("%s: Page request for invalid PASID %d: %08llx %08llx\n", > iommu->name, req->pasid, ((unsigned long long *)req)[0], > ((unsigned long long *)req)[1]); > Thanks Eric