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Commit bd0e5211 authored by Joerg Roedel's avatar Joerg Roedel Committed by Ingo Molnar
Browse files

x86, AMD IOMMU: add functions to initialize unity mappings 



This patch adds the functions which will initialize the unity mappings in the
device page tables.

Signed-off-by: default avatarJoerg Roedel <joerg.roedel@amd.com>
Cc: iommu@lists.linux-foundation.org
Cc: bhavna.sarathy@amd.com
Cc: Sebastian.Biemueller@amd.com
Cc: robert.richter@amd.com
Cc: joro@8bytes.org
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent a19ae1ec

arch/x86/kernel/amd_iommu.c

+122 −0
Original line number Diff line number Diff line
@@ -37,6 +37,9 @@ struct command { 
	u32 data[4];

};



static int dma_ops_unity_map(struct dma_ops_domain *dma_dom,

			     struct unity_map_entry *e);



static int __iommu_queue_command(struct amd_iommu *iommu, struct command *cmd)

{

	u32 tail, head;
@@ -144,3 +147,122 @@ static int iommu_flush_pages(struct amd_iommu *iommu, u16 domid, 
	return 0;

}



static int iommu_map(struct protection_domain *dom,

		     unsigned long bus_addr,

		     unsigned long phys_addr,

		     int prot)

{

	u64 __pte, *pte, *page;



	bus_addr  = PAGE_ALIGN(bus_addr);

	phys_addr = PAGE_ALIGN(bus_addr);



	/* only support 512GB address spaces for now */

	if (bus_addr > IOMMU_MAP_SIZE_L3 || !(prot & IOMMU_PROT_MASK))

		return -EINVAL;



	pte = &dom->pt_root[IOMMU_PTE_L2_INDEX(bus_addr)];



	if (!IOMMU_PTE_PRESENT(*pte)) {

		page = (u64 *)get_zeroed_page(GFP_KERNEL);

		if (!page)

			return -ENOMEM;

		*pte = IOMMU_L2_PDE(virt_to_phys(page));

	}



	pte = IOMMU_PTE_PAGE(*pte);

	pte = &pte[IOMMU_PTE_L1_INDEX(bus_addr)];



	if (!IOMMU_PTE_PRESENT(*pte)) {

		page = (u64 *)get_zeroed_page(GFP_KERNEL);

		if (!page)

			return -ENOMEM;

		*pte = IOMMU_L1_PDE(virt_to_phys(page));

	}



	pte = IOMMU_PTE_PAGE(*pte);

	pte = &pte[IOMMU_PTE_L0_INDEX(bus_addr)];



	if (IOMMU_PTE_PRESENT(*pte))

		return -EBUSY;



	__pte = phys_addr | IOMMU_PTE_P;

	if (prot & IOMMU_PROT_IR)

		__pte |= IOMMU_PTE_IR;

	if (prot & IOMMU_PROT_IW)

		__pte |= IOMMU_PTE_IW;



	*pte = __pte;



	return 0;

}



static int iommu_for_unity_map(struct amd_iommu *iommu,

			       struct unity_map_entry *entry)

{

	u16 bdf, i;



	for (i = entry->devid_start; i <= entry->devid_end; ++i) {

		bdf = amd_iommu_alias_table[i];

		if (amd_iommu_rlookup_table[bdf] == iommu)

			return 1;

	}



	return 0;

}



static int iommu_init_unity_mappings(struct amd_iommu *iommu)

{

	struct unity_map_entry *entry;

	int ret;



	list_for_each_entry(entry, &amd_iommu_unity_map, list) {

		if (!iommu_for_unity_map(iommu, entry))

			continue;

		ret = dma_ops_unity_map(iommu->default_dom, entry);

		if (ret)

			return ret;

	}



	return 0;

}



static int dma_ops_unity_map(struct dma_ops_domain *dma_dom,

			     struct unity_map_entry *e)

{

	u64 addr;

	int ret;



	for (addr = e->address_start; addr < e->address_end;

	     addr += PAGE_SIZE) {

		ret = iommu_map(&dma_dom->domain, addr, addr, e->prot);

		if (ret)

			return ret;

		/*

		 * if unity mapping is in aperture range mark the page

		 * as allocated in the aperture

		 */

		if (addr < dma_dom->aperture_size)

			__set_bit(addr >> PAGE_SHIFT, dma_dom->bitmap);

	}



	return 0;

}



static int init_unity_mappings_for_device(struct dma_ops_domain *dma_dom,

					  u16 devid)

{

	struct unity_map_entry *e;

	int ret;



	list_for_each_entry(e, &amd_iommu_unity_map, list) {

		if (!(devid >= e->devid_start && devid <= e->devid_end))

			continue;

		ret = dma_ops_unity_map(dma_dom, e);

		if (ret)

			return ret;

	}



	return 0;

}