From 2c1296d92ac0367364bcb73a43c12a0bdfbfee75 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 28 May 2015 18:41:32 +0200 Subject: [PATCH] iommu: Add iommu_get_domain_for_dev function This function can be used to request the current domain a device is attached to. Signed-off-by: Joerg Roedel --- drivers/iommu/iommu.c | 18 ++++++++++++++++++ include/linux/iommu.h | 6 ++++++ 2 files changed, 24 insertions(+) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 7bce522c2367..a0a38bd2668b 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -1076,6 +1076,24 @@ out_unlock: } EXPORT_SYMBOL_GPL(iommu_detach_device); +struct iommu_domain *iommu_get_domain_for_dev(struct device *dev) +{ + struct iommu_domain *domain; + struct iommu_group *group; + + group = iommu_group_get(dev); + /* FIXME: Remove this when groups a mandatory for iommu drivers */ + if (group == NULL) + return NULL; + + domain = group->domain; + + iommu_group_put(group); + + return domain; +} +EXPORT_SYMBOL_GPL(iommu_get_domain_for_dev); + /* * IOMMU groups are really the natrual working unit of the IOMMU, but * the IOMMU API works on domains and devices. Bridge that gap by diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 0546b8710ce3..683a1c4b15e7 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -193,6 +193,7 @@ extern int iommu_attach_device(struct iommu_domain *domain, struct device *dev); extern void iommu_detach_device(struct iommu_domain *domain, struct device *dev); +extern struct iommu_domain *iommu_get_domain_for_dev(struct device *dev); extern int iommu_map(struct iommu_domain *domain, unsigned long iova, phys_addr_t paddr, size_t size, int prot); extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, @@ -332,6 +333,11 @@ static inline void iommu_detach_device(struct iommu_domain *domain, { } +static inline struct iommu_domain *iommu_get_domain_for_dev(struct device *dev) +{ + return NULL; +} + static inline int iommu_map(struct iommu_domain *domain, unsigned long iova, phys_addr_t paddr, int gfp_order, int prot) { -- 2.20.1