gpu: host1x: Acquire a reference to the IOVA cache (f40e1590) · Commits · 戴 / test

The IOVA API uses a memory cache to allocate IOVA nodes from. To make sure that this cache is available, obtain a reference to it and release the reference when the cache is no longer needed. On 64-bit ARM this is hidden by the fact that the DMA mapping API gets that reference and never releases it. On 32-bit ARM, this is papered over by the Tegra DRM driver (the sole user of the host1x API requiring the cache) acquiring a reference to the IOVA cache for its own purposes. However, there may be additional users of this API in the future, so fix this upfront to avoid surprises. Fixes: ("gpu: host1x: Add IOMMU support") Reviewed-by:

Dmitry Osipenko <digetx@gmail.com> Signed-off-by:

Thierry Reding <treding@nvidia.com>

drivers/gpu/host1x/dev.c

+10 −1

Original line number	Diff line number	Diff line
		@@ -223,10 +223,14 @@ static int host1x_probe(struct platform_device *pdev)
		struct iommu_domain_geometry *geometry;
		unsigned long order;

		err = iova_cache_get();
		if (err < 0)
		goto put_group;

		host->domain = iommu_domain_alloc(&platform_bus_type);
		if (!host->domain) {
		err = -ENOMEM;
		goto put_group;
		goto put_cache;
		}

		err = iommu_attach_group(host->domain, host->group);
		@@ -234,6 +238,7 @@ static int host1x_probe(struct platform_device *pdev)
		if (err == -ENODEV) {
		iommu_domain_free(host->domain);
		host->domain = NULL;
		iova_cache_put();
		iommu_group_put(host->group);
		host->group = NULL;
		goto skip_iommu;
		@@ -308,6 +313,9 @@ fail_detach_device:
		fail_free_domain:
		if (host->domain)
		iommu_domain_free(host->domain);
		put_cache:
		if (host->group)
		iova_cache_put();
		put_group:
		iommu_group_put(host->group);

		@@ -328,6 +336,7 @@ static int host1x_remove(struct platform_device *pdev)
		put_iova_domain(&host->iova);
		iommu_detach_group(host->domain, host->group);
		iommu_domain_free(host->domain);
		iova_cache_put();
		iommu_group_put(host->group);
		}

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