KVM: MIPS/MMU: Convert commpage fault handling to page tables

Now that we have GVA page tables and an optimised TLB refill handler in
place, convert the handling of commpage faults from the guest kernel to
fill the GVA page table and invalidate the TLB entry, rather than
filling the wired TLB entry directly.

For simplicity we no longer use a wired entry for the commpage (refill
should be much cheaper with the fast-path handler anyway). Since we
don't need to manipulate the TLB directly any longer, move the function
from tlb.c to mmu.c. This puts it closer to the similar functions
handling KSeg0 and TLB mapped page faults from the guest.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
This commit is contained in:
James Hogan
2016-10-08 01:16:21 +01:00
parent 7e3d2a750b
commit 4c86460cbc
4 changed files with 22 additions and 80 deletions

View File

@@ -52,11 +52,6 @@ static u32 kvm_mips_get_user_asid(struct kvm_vcpu *vcpu)
return cpu_asid(cpu, user_mm);
}
inline u32 kvm_mips_get_commpage_asid(struct kvm_vcpu *vcpu)
{
return vcpu->kvm->arch.commpage_tlb;
}
/* Structure defining an tlb entry data set. */
void kvm_mips_dump_host_tlbs(void)
@@ -104,45 +99,6 @@ void kvm_mips_dump_guest_tlbs(struct kvm_vcpu *vcpu)
}
EXPORT_SYMBOL_GPL(kvm_mips_dump_guest_tlbs);
int kvm_mips_handle_commpage_tlb_fault(unsigned long badvaddr,
struct kvm_vcpu *vcpu)
{
kvm_pfn_t pfn;
unsigned long flags, old_entryhi = 0, vaddr = 0;
unsigned long entrylo[2] = { 0, 0 };
unsigned int pair_idx;
pfn = PFN_DOWN(virt_to_phys(vcpu->arch.kseg0_commpage));
pair_idx = (badvaddr >> PAGE_SHIFT) & 1;
entrylo[pair_idx] = mips3_paddr_to_tlbpfn(pfn << PAGE_SHIFT) |
((_page_cachable_default >> _CACHE_SHIFT) << ENTRYLO_C_SHIFT) |
ENTRYLO_D | ENTRYLO_V;
local_irq_save(flags);
old_entryhi = read_c0_entryhi();
vaddr = badvaddr & (PAGE_MASK << 1);
write_c0_entryhi(vaddr | kvm_mips_get_kernel_asid(vcpu));
write_c0_entrylo0(entrylo[0]);
write_c0_entrylo1(entrylo[1]);
write_c0_index(kvm_mips_get_commpage_asid(vcpu));
mtc0_tlbw_hazard();
tlb_write_indexed();
tlbw_use_hazard();
kvm_debug("@ %#lx idx: %2d [entryhi(R): %#lx] entrylo0 (R): 0x%08lx, entrylo1(R): 0x%08lx\n",
vcpu->arch.pc, read_c0_index(), read_c0_entryhi(),
read_c0_entrylo0(), read_c0_entrylo1());
/* Restore old ASID */
write_c0_entryhi(old_entryhi);
mtc0_tlbw_hazard();
local_irq_restore(flags);
return 0;
}
EXPORT_SYMBOL_GPL(kvm_mips_handle_commpage_tlb_fault);
int kvm_mips_guest_tlb_lookup(struct kvm_vcpu *vcpu, unsigned long entryhi)
{
int i;