Commit 273df963 authored by Robin Murphy's avatar Robin Murphy Committed by Joerg Roedel
Browse files

iommu/dma: Make PCI window reservation generic 



Now that we're applying the IOMMU API reserved regions to our IOVA
domains, we shouldn't need to privately special-case PCI windows, or
indeed anything else which isn't specific to our iommu-dma layer.
However, since those aren't IOMMU-specific either, rather than start
duplicating code into IOMMU drivers let's transform the existing
function into an iommu_get_resv_regions() helper that they can share.

Signed-off-by: default avatarRobin Murphy <robin.murphy@arm.com>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 7c1b058c

drivers/iommu/arm-smmu-v3.c

+2 −0
Original line number Diff line number Diff line
@@ -1893,6 +1893,8 @@ static void arm_smmu_get_resv_regions(struct device *dev, 
		return;



	list_add_tail(&region->list, head);



	iommu_dma_get_resv_regions(dev, head);

}



static void arm_smmu_put_resv_regions(struct device *dev,

drivers/iommu/arm-smmu.c

+2 −0
Original line number Diff line number Diff line
@@ -1613,6 +1613,8 @@ static void arm_smmu_get_resv_regions(struct device *dev, 
		return;



	list_add_tail(&region->list, head);



	iommu_dma_get_resv_regions(dev, head);

}



static void arm_smmu_put_resv_regions(struct device *dev,

drivers/iommu/dma-iommu.c

+28 −10
Original line number Diff line number Diff line
@@ -167,22 +167,43 @@ void iommu_put_dma_cookie(struct iommu_domain *domain) 
}

EXPORT_SYMBOL(iommu_put_dma_cookie);



static void iova_reserve_pci_windows(struct pci_dev *dev,

		struct iova_domain *iovad)

/**

 * iommu_dma_get_resv_regions - Reserved region driver helper

 * @dev: Device from iommu_get_resv_regions()

 * @list: Reserved region list from iommu_get_resv_regions()

 *

 * IOMMU drivers can use this to implement their .get_resv_regions callback

 * for general non-IOMMU-specific reservations. Currently, this covers host

 * bridge windows for PCI devices.

 */

void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list)

{

	struct pci_host_bridge *bridge = pci_find_host_bridge(dev->bus);

	struct pci_host_bridge *bridge;

	struct resource_entry *window;

	unsigned long lo, hi;



	if (!dev_is_pci(dev))

		return;



	bridge = pci_find_host_bridge(to_pci_dev(dev)->bus);

	resource_list_for_each_entry(window, &bridge->windows) {

		struct iommu_resv_region *region;

		phys_addr_t start;

		size_t length;



		if (resource_type(window->res) != IORESOURCE_MEM)

			continue;



		lo = iova_pfn(iovad, window->res->start - window->offset);

		hi = iova_pfn(iovad, window->res->end - window->offset);

		reserve_iova(iovad, lo, hi);

		start = window->res->start - window->offset;

		length = window->res->end - window->res->start + 1;

		region = iommu_alloc_resv_region(start, length, 0,

				IOMMU_RESV_RESERVED);

		if (!region)

			return;



		list_add_tail(&region->list, list);

	}

}

EXPORT_SYMBOL(iommu_dma_get_resv_regions);



static int cookie_init_hw_msi_region(struct iommu_dma_cookie *cookie,

		phys_addr_t start, phys_addr_t end)
@@ -218,9 +239,6 @@ static int iova_reserve_iommu_regions(struct device *dev, 
	LIST_HEAD(resv_regions);

	int ret = 0;



	if (dev_is_pci(dev))

		iova_reserve_pci_windows(to_pci_dev(dev), iovad);



	iommu_get_resv_regions(dev, &resv_regions);

	list_for_each_entry(region, &resv_regions, list) {

		unsigned long lo, hi;

include/linux/dma-iommu.h

+5 −0
Original line number Diff line number Diff line
@@ -71,6 +71,7 @@ int iommu_dma_mapping_error(struct device *dev, dma_addr_t dma_addr); 


/* The DMA API isn't _quite_ the whole story, though... */

void iommu_dma_map_msi_msg(int irq, struct msi_msg *msg);

void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list);



#else
@@ -100,6 +101,10 @@ static inline void iommu_dma_map_msi_msg(int irq, struct msi_msg *msg) 
{

}



static inline void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list)

{

}



#endif	/* CONFIG_IOMMU_DMA */

#endif	/* __KERNEL__ */

#endif	/* __DMA_IOMMU_H */

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