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arm64/dma-mapping: Remove default domain workaround

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With the IOMMU core now taking care of default domains for groups
regardless of bus type, we can gleefully rip out this stop-gap, as
slight recompense for having to expand the other one.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Robin Murphy 2016-04-19 17:01:32 +01:00 committed by Will Deacon
parent 226d89cbb2
commit 921b1f52c9
1 changed files with 8 additions and 44 deletions
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52
arch/arm64/mm/dma-mapping.c
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@ -804,57 +804,24 @@ struct iommu_dma_notifier_data {
static LIST_HEAD(iommu_dma_masters);
static DEFINE_MUTEX(iommu_dma_notifier_lock);
/*
* Temporarily "borrow" a domain feature flag to to tell if we had to resort
* to creating our own domain here, in case we need to clean it up again.
*/
#define __IOMMU_DOMAIN_FAKE_DEFAULT (1U << 31)
static bool do_iommu_attach(struct device *dev, const struct iommu_ops *ops,
u64 dma_base, u64 size)
{
struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
/*
* Best case: The device is either part of a group which was
* already attached to a domain in a previous call, or it's
* been put in a default DMA domain by the IOMMU core.
* If the IOMMU driver has the DMA domain support that we require,
* then the IOMMU core will have already configured a group for this
* device, and allocated the default domain for that group.
*/
if (!domain) {
/*
* Urgh. The IOMMU core isn't going to do default domains
* for non-PCI devices anyway, until it has some means of
* abstracting the entirely implementation-specific
* sideband data/SoC topology/unicorn dust that may or
* may not differentiate upstream masters.
* So until then, HORRIBLE HACKS!
*/
domain = ops->domain_alloc(IOMMU_DOMAIN_DMA);
if (!domain)
goto out_no_domain;
domain->ops = ops;
domain->type = IOMMU_DOMAIN_DMA | __IOMMU_DOMAIN_FAKE_DEFAULT;
if (iommu_attach_device(domain, dev))
goto out_put_domain;
if (!domain || iommu_dma_init_domain(domain, dma_base, size)) {
pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA ops\n",
dev_name(dev));
return false;
}
if (iommu_dma_init_domain(domain, dma_base, size))
goto out_detach;
dev->archdata.dma_ops = &iommu_dma_ops;
return true;
out_detach:
iommu_detach_device(domain, dev);
out_put_domain:
if (domain->type & __IOMMU_DOMAIN_FAKE_DEFAULT)
iommu_domain_free(domain);
out_no_domain:
pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA ops\n",
dev_name(dev));
return false;
}
static void queue_iommu_attach(struct device *dev, const struct iommu_ops *ops,
@ -971,11 +938,8 @@ void arch_teardown_dma_ops(struct device *dev)
{
struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
if (domain) {
if (WARN_ON(domain))
iommu_detach_device(domain, dev);
if (domain->type & __IOMMU_DOMAIN_FAKE_DEFAULT)
iommu_domain_free(domain);
}
dev->archdata.dma_ops = NULL;
}