From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f70.google.com (mail-oi0-f70.google.com [209.85.218.70]) by kanga.kvack.org (Postfix) with ESMTP id 1A1806B0685 for ; Fri, 11 May 2018 15:08:06 -0400 (EDT) Received: by mail-oi0-f70.google.com with SMTP id c23-v6so3488207oic.2 for ; Fri, 11 May 2018 12:08:06 -0700 (PDT) Received: from foss.arm.com (foss.arm.com. [217.140.101.70]) by mx.google.com with ESMTP id 188-v6si1199342oia.429.2018.05.11.12.08.05 for ; Fri, 11 May 2018 12:08:05 -0700 (PDT) From: Jean-Philippe Brucker Subject: [PATCH v2 06/40] iommu/sva: Search mm by PASID Date: Fri, 11 May 2018 20:06:07 +0100 Message-Id: <20180511190641.23008-7-jean-philippe.brucker@arm.com> In-Reply-To: <20180511190641.23008-1-jean-philippe.brucker@arm.com> References: <20180511190641.23008-1-jean-philippe.brucker@arm.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, devicetree@vger.kernel.org, iommu@lists.linux-foundation.org, kvm@vger.kernel.org, linux-mm@kvack.org Cc: joro@8bytes.org, will.deacon@arm.com, robin.murphy@arm.com, alex.williamson@redhat.com, tn@semihalf.com, liubo95@huawei.com, thunder.leizhen@huawei.com, xieyisheng1@huawei.com, xuzaibo@huawei.com, ilias.apalodimas@linaro.org, jonathan.cameron@huawei.com, liudongdong3@huawei.com, shunyong.yang@hxt-semitech.com, nwatters@codeaurora.org, okaya@codeaurora.org, jcrouse@codeaurora.org, rfranz@cavium.com, dwmw2@infradead.org, jacob.jun.pan@linux.intel.com, yi.l.liu@intel.com, ashok.raj@intel.com, kevin.tian@intel.com, baolu.lu@linux.intel.com, robdclark@gmail.com, christian.koenig@amd.com, bharatku@xilinx.com, rgummal@xilinx.com The fault handler will need to find an mm given its PASID. This is the reason we have an IDR for storing address spaces, so hook it up. Signed-off-by: Jean-Philippe Brucker --- drivers/iommu/iommu-sva.c | 26 ++++++++++++++++++++++++++ include/linux/iommu.h | 6 ++++++ 2 files changed, 32 insertions(+) diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c index e9afae2537a2..5abe0f0b445c 100644 --- a/drivers/iommu/iommu-sva.c +++ b/drivers/iommu/iommu-sva.c @@ -736,3 +736,29 @@ void __iommu_sva_unbind_dev_all(struct device *dev) } } EXPORT_SYMBOL_GPL(__iommu_sva_unbind_dev_all); + +/** + * iommu_sva_find() - Find mm associated to the given PASID + * @pasid: Process Address Space ID assigned to the mm + * + * Returns the mm corresponding to this PASID, or NULL if not found. A reference + * to the mm is taken, and must be released with mmput(). + */ +struct mm_struct *iommu_sva_find(int pasid) +{ + struct io_mm *io_mm; + struct mm_struct *mm = NULL; + + spin_lock(&iommu_sva_lock); + io_mm = idr_find(&iommu_pasid_idr, pasid); + if (io_mm && io_mm_get_locked(io_mm)) { + if (mmget_not_zero(io_mm->mm)) + mm = io_mm->mm; + + io_mm_put_locked(io_mm); + } + spin_unlock(&iommu_sva_lock); + + return mm; +} +EXPORT_SYMBOL_GPL(iommu_sva_find); diff --git a/include/linux/iommu.h b/include/linux/iommu.h index caa6f79785b9..faf3390ce89d 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -1001,6 +1001,7 @@ extern int __iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, extern int __iommu_sva_unbind_device(struct device *dev, int pasid); extern void __iommu_sva_unbind_dev_all(struct device *dev); +extern struct mm_struct *iommu_sva_find(int pasid); #else /* CONFIG_IOMMU_SVA */ static inline int iommu_sva_device_init(struct device *dev, unsigned long features, @@ -1030,6 +1031,11 @@ static inline int __iommu_sva_unbind_device(struct device *dev, int pasid) static inline void __iommu_sva_unbind_dev_all(struct device *dev) { } + +static inline struct mm_struct *iommu_sva_find(int pasid) +{ + return NULL; +} #endif /* CONFIG_IOMMU_SVA */ #endif /* __LINUX_IOMMU_H */ -- 2.17.0