admin/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2025-12-07 20:06:24 +00:00
Code Issues Packages Projects Releases Wiki Activity

KVM: selftests: Use a loop to create guest page tables

Browse Source 
Walk the guest page tables via a loop when creating new mappings,
instead of using unique variables for each level of the page tables.

This simplifies the code and makes it easier to support 5-level paging
in the future.

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Link: https://patch.msgid.link/20251028225827.2269128-2-jmattson@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
This commit is contained in:
Jim Mattson
2025-10-28 15:30:39 -07:00
committed by Sean Christopherson
parent ff736dba47
commit ae5b498b8d
1 changed files with 11 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
tools/testing/selftests/kvm/lib/x86/processor.c
View File

@@ -218,8 +218,8 @@ static uint64_t *virt_create_upper_pte(struct kvm_vm *vm,
void __virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr, int level)
{
const uint64_t pg_size = PG_LEVEL_SIZE(level);
uint64_t *pml4e, *pdpe, *pde;
uint64_t *pte;
uint64_t *pte = &vm->pgd;
int current_level;
TEST_ASSERT(vm->mode == VM_MODE_PXXV48_4K,
"Unknown or unsupported guest mode, mode: 0x%x", vm->mode);
@@ -243,20 +243,17 @@ void __virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr, int level)
* Allocate upper level page tables, if not already present. Return
* early if a hugepage was created.
*/
pml4e = virt_create_upper_pte(vm, &vm->pgd, vaddr, paddr, PG_LEVEL_512G, level);
if (*pml4e & PTE_LARGE_MASK)
return;
pdpe = virt_create_upper_pte(vm, pml4e, vaddr, paddr, PG_LEVEL_1G, level);
if (*pdpe & PTE_LARGE_MASK)
return;
pde = virt_create_upper_pte(vm, pdpe, vaddr, paddr, PG_LEVEL_2M, level);
if (*pde & PTE_LARGE_MASK)
return;
for (current_level = vm->pgtable_levels;
current_level > PG_LEVEL_4K;
current_level--) {
pte = virt_create_upper_pte(vm, pte, vaddr, paddr,
current_level, level);
if (*pte & PTE_LARGE_MASK)
return;
}
/* Fill in page table entry. */
pte = virt_get_pte(vm, pde, vaddr, PG_LEVEL_4K);
pte = virt_get_pte(vm, pte, vaddr, PG_LEVEL_4K);
TEST_ASSERT(!(*pte & PTE_PRESENT_MASK),
"PTE already present for 4k page at vaddr: 0x%lx", vaddr);
*pte = PTE_PRESENT_MASK | PTE_WRITABLE_MASK | (paddr & PHYSICAL_PAGE_MASK);