On 9/27/22 00:20, Sean Christopherson wrote:
void __virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
uint64_t nr_bytes, size_t page_size)
{
uint64_t nr_pages = DIV_ROUND_UP(nr_bytes, page_size);
TEST_ASSERT(vaddr + size > vaddr, "Vaddr overflow");
TEST_ASSERT(paddr + size > paddr, "Paddr overflow");
while (npages--) {
virt_pg_map(vm, vaddr, paddr);
vaddr += page_size;
paddr += page_size;
}
}
void virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
uint64_t nr_bytes)
{
__virt_map(vm, vaddr, paddr, nr_bytes, vm->page_size);
}
I would just keep nr_pages in virt_map to begin with, for the sake of
this patch. Changing virt_map can be done later (and should be separate
anyway).
- virt_map(vm, HPAGE_GVA, HPAGE_GPA, HPAGE_SLOT_NPAGES);
+ /*
+ * Use 2MiB virtual mappings so that KVM can map the region with huge
+ * pages even if TDP is disabled.
+ */
+ virt_map_2m(vm, HPAGE_GVA, HPAGE_GPA, HPAGE_SLOT_2MB_PAGES);
Hmm, what about probing TDP support and deliberately using 4KiB pages when TDP is
enabled? That would give a bit of bonus coverage by verifying that KVM creates
huge pages irrespective of guest mapping level.
Nice idea indeed.
Paolo
