diff options
Diffstat (limited to 'drivers/iommu/iommu.c')
| -rw-r--r-- | drivers/iommu/iommu.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index caaf563d38ae..d199d144460c 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -39,6 +39,7 @@ static struct kset *iommu_group_kset; static DEFINE_IDA(iommu_group_ida); +static DEFINE_IDA(iommu_global_pasid_ida); static unsigned int iommu_def_domain_type __read_mostly; static bool iommu_dma_strict __read_mostly = IS_ENABLED(CONFIG_IOMMU_DEFAULT_DMA_STRICT); @@ -3400,3 +3401,30 @@ struct iommu_domain *iommu_sva_domain_alloc(struct device *dev, return domain; } + +ioasid_t iommu_alloc_global_pasid(struct device *dev) +{ + int ret; + + /* max_pasids == 0 means that the device does not support PASID */ + if (!dev->iommu->max_pasids) + return IOMMU_PASID_INVALID; + + /* + * max_pasids is set up by vendor driver based on number of PASID bits + * supported but the IDA allocation is inclusive. + */ + ret = ida_alloc_range(&iommu_global_pasid_ida, IOMMU_FIRST_GLOBAL_PASID, + dev->iommu->max_pasids - 1, GFP_KERNEL); + return ret < 0 ? IOMMU_PASID_INVALID : ret; +} +EXPORT_SYMBOL_GPL(iommu_alloc_global_pasid); + +void iommu_free_global_pasid(ioasid_t pasid) +{ + if (WARN_ON(pasid == IOMMU_PASID_INVALID)) + return; + + ida_free(&iommu_global_pasid_ida, pasid); +} +EXPORT_SYMBOL_GPL(iommu_free_global_pasid); |