From efc30a8f15a7981737297f9e9c62fb814d74e268 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Fri, 9 Dec 2022 13:23:08 -0400 Subject: [PATCH] iommu: Add iommu_group_has_isolated_msi() Compute the isolated_msi over all the devices in the IOMMU group because iommufd and vfio both need to know that the entire group is isolated before granting access to it. Link: https://lore.kernel.org/r/2-v3-3313bb5dd3a3+10f11-secure_msi_jgg@nvidia.com Tested-by: Matthew Rosato Reviewed-by: Kevin Tian Reviewed-by: Lu Baolu Signed-off-by: Jason Gunthorpe --- drivers/iommu/iommu.c | 26 ++++++++++++++++++++++++++ include/linux/iommu.h | 1 + 2 files changed, 27 insertions(+) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index de91dd8..4c2199a 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -30,6 +30,7 @@ #include #include #include +#include #include "dma-iommu.h" @@ -1898,6 +1899,31 @@ bool device_iommu_capable(struct device *dev, enum iommu_cap cap) EXPORT_SYMBOL_GPL(device_iommu_capable); /** + * iommu_group_has_isolated_msi() - Compute msi_device_has_isolated_msi() + * for a group + * @group: Group to query + * + * IOMMU groups should not have differing values of + * msi_device_has_isolated_msi() for devices in a group. However nothing + * directly prevents this, so ensure mistakes don't result in isolation failures + * by checking that all the devices are the same. + */ +bool iommu_group_has_isolated_msi(struct iommu_group *group) +{ + struct group_device *group_dev; + bool ret = true; + + mutex_lock(&group->mutex); + list_for_each_entry(group_dev, &group->devices, list) { + ret &= msi_device_has_isolated_msi(group_dev->dev) || + device_iommu_capable(group_dev->dev, IOMMU_CAP_INTR_REMAP); + } + mutex_unlock(&group->mutex); + return ret; +} +EXPORT_SYMBOL_GPL(iommu_group_has_isolated_msi); + +/** * iommu_set_fault_handler() - set a fault handler for an iommu domain * @domain: iommu domain * @handler: fault handler diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 46e1347..9b7a9fa 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -455,6 +455,7 @@ static inline const struct iommu_ops *dev_iommu_ops(struct device *dev) extern int bus_iommu_probe(struct bus_type *bus); extern bool iommu_present(struct bus_type *bus); extern bool device_iommu_capable(struct device *dev, enum iommu_cap cap); +extern bool iommu_group_has_isolated_msi(struct iommu_group *group); extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus); extern struct iommu_group *iommu_group_get_by_id(int id); extern void iommu_domain_free(struct iommu_domain *domain); -- 2.7.4