From c208916fe6c7b84e3ec95cd91853039596eeb2cf Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Wed, 11 Aug 2021 13:21:34 +0100 Subject: iommu: Express DMA strictness via the domain type Eliminate the iommu_get_dma_strict() indirection and pipe the information through the domain type from the beginning. Besides the flow simplification this also has several nice side-effects: - Automatically implies strict mode for untrusted devices by virtue of their IOMMU_DOMAIN_DMA override. - Ensures that we only end up using flush queues for drivers which are aware of them and can actually benefit. - Allows us to handle flush queue init failure by falling back to strict mode instead of leaving it to possibly blow up later. Reviewed-by: Lu Baolu Signed-off-by: Robin Murphy Link: https://lore.kernel.org/r/47083d69155577f1367877b1594921948c366eb3.1628682049.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel --- drivers/iommu/iommu.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) (limited to 'drivers/iommu/iommu.c') diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 17d6728f5a09..e09f0d433683 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -136,6 +136,9 @@ static int __init iommu_subsys_init(void) } } + if (!iommu_default_passthrough() && !iommu_dma_strict) + iommu_def_domain_type = IOMMU_DOMAIN_DMA_FQ; + pr_info("Default domain type: %s %s\n", iommu_domain_type_str(iommu_def_domain_type), (iommu_cmd_line & IOMMU_CMD_LINE_DMA_API) ? @@ -355,17 +358,10 @@ early_param("iommu.strict", iommu_dma_setup); void iommu_set_dma_strict(void) { iommu_dma_strict = true; + if (iommu_def_domain_type == IOMMU_DOMAIN_DMA_FQ) + iommu_def_domain_type = IOMMU_DOMAIN_DMA; } -bool iommu_get_dma_strict(struct iommu_domain *domain) -{ - /* only allow lazy flushing for DMA domains */ - if (domain->type == IOMMU_DOMAIN_DMA) - return iommu_dma_strict; - return true; -} -EXPORT_SYMBOL_GPL(iommu_get_dma_strict); - static ssize_t iommu_group_attr_show(struct kobject *kobj, struct attribute *__attr, char *buf) { -- cgit