From mboxrd@z Thu Jan 1 00:00:00 1970 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> References: <20180511190641.23008-1-jean-philippe.brucker@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180511190641.23008-1-jean-philippe.brucker-5wv7dgnIgG8@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-acpi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org Cc: xuzaibo-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, okaya-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, ashok.raj-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, bharatku-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org, rfranz-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org, rgummal-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org, ilias.apalodimas-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, christian.koenig-5C7GfCeVMHo@public.gmane.org List-Id: iommu@lists.linux-foundation.org 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