Commit f681d686 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
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KVM: selftests: Add PTE helper for x86-64 in preparation for hugepages 



Add a helper to retrieve a PTE pointer given a PFN, address, and level
in preparation for adding hugepage support.

No functional change intended.

Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Message-Id: <20210622200529.3650424-17-seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 6d96ca6a

tools/testing/selftests/kvm/lib/x86_64/processor.c

+31 −28
Original line number Diff line number Diff line
@@ -216,10 +216,21 @@ void virt_pgd_alloc(struct kvm_vm *vm) 
	}

}



static void *virt_get_pte(struct kvm_vm *vm, uint64_t pt_pfn, uint64_t vaddr,

			  int level)

{

	uint64_t *page_table = addr_gpa2hva(vm, pt_pfn << vm->page_shift);

	int index = vaddr >> (vm->page_shift + level * 9) & 0x1ffu;



	return &page_table[index];

}



void virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr)

{

	uint16_t index[4];

	struct pageMapL4Entry *pml4e;

	struct pageDirectoryPointerEntry *pdpe;

	struct pageDirectoryEntry *pde;

	struct pageTableEntry *pte;



	TEST_ASSERT(vm->mode == VM_MODE_PXXV48_4K, "Attempt to use "

		"unknown or unsupported guest mode, mode: 0x%x", vm->mode);
@@ -241,43 +252,35 @@ void virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr) 
		"  paddr: 0x%lx vm->max_gfn: 0x%lx vm->page_size: 0x%x",

		paddr, vm->max_gfn, vm->page_size);



	index[0] = (vaddr >> 12) & 0x1ffu;

	index[1] = (vaddr >> 21) & 0x1ffu;

	index[2] = (vaddr >> 30) & 0x1ffu;

	index[3] = (vaddr >> 39) & 0x1ffu;



	/* Allocate page directory pointer table if not present. */

	pml4e = addr_gpa2hva(vm, vm->pgd);

	if (!pml4e[index[3]].present) {

		pml4e[index[3]].pfn = vm_alloc_page_table(vm) >> vm->page_shift;

		pml4e[index[3]].writable = true;

		pml4e[index[3]].present = true;

	pml4e = virt_get_pte(vm, vm->pgd >> vm->page_shift, vaddr, 3);

	if (!pml4e->present) {

		pml4e->pfn = vm_alloc_page_table(vm) >> vm->page_shift;

		pml4e->writable = true;

		pml4e->present = true;

	}



	/* Allocate page directory table if not present. */

	struct pageDirectoryPointerEntry *pdpe;

	pdpe = addr_gpa2hva(vm, pml4e[index[3]].pfn * vm->page_size);

	if (!pdpe[index[2]].present) {

		pdpe[index[2]].pfn = vm_alloc_page_table(vm) >> vm->page_shift;

		pdpe[index[2]].writable = true;

		pdpe[index[2]].present = true;

	pdpe = virt_get_pte(vm, pml4e->pfn, vaddr, 2);

	if (!pdpe->present) {

		pdpe->pfn = vm_alloc_page_table(vm) >> vm->page_shift;

		pdpe->writable = true;

		pdpe->present = true;

	}



	/* Allocate page table if not present. */

	struct pageDirectoryEntry *pde;

	pde = addr_gpa2hva(vm, pdpe[index[2]].pfn * vm->page_size);

	if (!pde[index[1]].present) {

		pde[index[1]].pfn = vm_alloc_page_table(vm) >> vm->page_shift;

		pde[index[1]].writable = true;

		pde[index[1]].present = true;

	pde = virt_get_pte(vm, pdpe->pfn, vaddr, 1);

	if (!pde->present) {

		pde->pfn = vm_alloc_page_table(vm) >> vm->page_shift;

		pde->writable = true;

		pde->present = true;

	}



	/* Fill in page table entry. */

	struct pageTableEntry *pte;

	pte = addr_gpa2hva(vm, pde[index[1]].pfn * vm->page_size);

	pte[index[0]].pfn = paddr >> vm->page_shift;

	pte[index[0]].writable = true;

	pte[index[0]].present = 1;

	pte = virt_get_pte(vm, pde->pfn, vaddr, 0);

	pte->pfn = paddr >> vm->page_shift;

	pte->writable = true;

	pte->present = 1;

}



void virt_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent)