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| author | Robin Murphy <robin.murphy@arm.com> | 2021-08-11 13:21:34 +0100 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2021-08-18 13:27:49 +0200 |
| commit | c208916fe6c7b84e3ec95cd91853039596eeb2cf (patch) | |
| tree | 735bb051c9c011787d0e9f34c0a6f9ce1d89b67d /drivers/iommu | |
| parent | 78ca078459d779319a22a8e2a18fc491da8a229b (diff) | |
| download | linux-c208916fe6c7b84e3ec95cd91853039596eeb2cf.tar.bz2 | |
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 <baolu.lu@linux.intel.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/47083d69155577f1367877b1594921948c366eb3.1628682049.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/dma-iommu.c | 10 | ||||
| -rw-r--r-- | drivers/iommu/iommu.c | 14 |
2 files changed, 11 insertions, 13 deletions
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 17ac3dd4f23e..b7ae855c1e89 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -370,13 +370,15 @@ static int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, init_iova_domain(iovad, 1UL << order, base_pfn); - if (!cookie->fq_domain && !dev_is_untrusted(dev) && - domain->ops->flush_iotlb_all && !iommu_get_dma_strict(domain)) { + /* If the FQ fails we can simply fall back to strict mode */ + if (domain->type == IOMMU_DOMAIN_DMA_FQ && !cookie->fq_domain) { if (init_iova_flush_queue(iovad, iommu_dma_flush_iotlb_all, - iommu_dma_entry_dtor)) + iommu_dma_entry_dtor)) { pr_warn("iova flush queue initialization failed\n"); - else + domain->type = IOMMU_DOMAIN_DMA; + } else { cookie->fq_domain = domain; + } } return iova_reserve_iommu_regions(dev, domain); 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) { |