Allow iommu_change_dev_def_domain() to create a new default domain, keeping the same as current.
Also remove comment about the function purpose, which will become stale. Signed-off-by: John Garry <john.ga...@huawei.com> --- drivers/iommu/iommu.c | 49 ++++++++++++++++++++++--------------------- include/linux/iommu.h | 1 + 2 files changed, 26 insertions(+), 24 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 5e7ed969b870..df9ffd76c184 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -3124,6 +3124,7 @@ u32 iommu_sva_get_pasid(struct iommu_sva *handle) } EXPORT_SYMBOL_GPL(iommu_sva_get_pasid); + /* * Changes the default domain of an iommu group that has *only* one device * @@ -3134,10 +3135,6 @@ EXPORT_SYMBOL_GPL(iommu_sva_get_pasid); * * Returns 0 on success and error code on failure * - * Note: - * 1. Presently, this function is called only when user requests to change the - * group's default domain type through /sys/kernel/iommu_groups/<grp_id>/type - * Please take a closer look if intended to use for other purposes. */ static int iommu_change_dev_def_domain(struct iommu_group *group, struct device *prev_dev, int type) @@ -3190,28 +3187,32 @@ static int iommu_change_dev_def_domain(struct iommu_group *group, goto out; } - dev_def_dom = iommu_get_def_domain_type(dev); - if (!type) { + if (type == __IOMMU_DOMAIN_SAME) { + type = prev_dom->type; + } else { + dev_def_dom = iommu_get_def_domain_type(dev); + if (!type) { + /* + * If the user hasn't requested any specific type of domain and + * if the device supports both the domains, then default to the + * domain the device was booted with + */ + type = dev_def_dom ? : iommu_def_domain_type; + } else if (dev_def_dom && type != dev_def_dom) { + dev_err_ratelimited(prev_dev, "Device cannot be in %s domain\n", + iommu_domain_type_str(type)); + ret = -EINVAL; + goto out; + } + /* - * If the user hasn't requested any specific type of domain and - * if the device supports both the domains, then default to the - * domain the device was booted with + * Switch to a new domain only if the requested domain type is different + * from the existing default domain type */ - type = dev_def_dom ? : iommu_def_domain_type; - } else if (dev_def_dom && type != dev_def_dom) { - dev_err_ratelimited(prev_dev, "Device cannot be in %s domain\n", - iommu_domain_type_str(type)); - ret = -EINVAL; - goto out; - } - - /* - * Switch to a new domain only if the requested domain type is different - * from the existing default domain type - */ - if (prev_dom->type == type) { - ret = 0; - goto out; + if (prev_dom->type == type) { + ret = 0; + goto out; + } } /* We can bring up a flush queue without tearing down the domain */ diff --git a/include/linux/iommu.h b/include/linux/iommu.h index de0c57a567c8..d242fccc7c2d 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -62,6 +62,7 @@ struct iommu_domain_geometry { implementation */ #define __IOMMU_DOMAIN_PT (1U << 2) /* Domain is identity mapped */ #define __IOMMU_DOMAIN_DMA_FQ (1U << 3) /* DMA-API uses flush queue */ +#define __IOMMU_DOMAIN_SAME (1U << 4) /* Keep same type (internal) */ /* * This are the possible domain-types -- 2.26.2 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu