From d0b2f91bede3bd5e3d24dd6803e56eee959c1797 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Thu, 20 Oct 2016 00:10:27 -0300 Subject: Linux-libre 4.8.2-gnu --- arch/mips/kvm/mmu.c | 395 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 395 insertions(+) create mode 100644 arch/mips/kvm/mmu.c (limited to 'arch/mips/kvm/mmu.c') diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c new file mode 100644 index 000000000..121008c0f --- /dev/null +++ b/arch/mips/kvm/mmu.c @@ -0,0 +1,395 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * KVM/MIPS MMU handling in the KVM module. + * + * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved. + * Authors: Sanjay Lal + */ + +#include +#include +#include + +static u32 kvm_mips_get_kernel_asid(struct kvm_vcpu *vcpu) +{ + int cpu = smp_processor_id(); + + return vcpu->arch.guest_kernel_asid[cpu] & + cpu_asid_mask(&cpu_data[cpu]); +} + +static u32 kvm_mips_get_user_asid(struct kvm_vcpu *vcpu) +{ + int cpu = smp_processor_id(); + + return vcpu->arch.guest_user_asid[cpu] & + cpu_asid_mask(&cpu_data[cpu]); +} + +static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn) +{ + int srcu_idx, err = 0; + kvm_pfn_t pfn; + + if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE) + return 0; + + srcu_idx = srcu_read_lock(&kvm->srcu); + pfn = gfn_to_pfn(kvm, gfn); + + if (is_error_noslot_pfn(pfn)) { + kvm_err("Couldn't get pfn for gfn %#llx!\n", gfn); + err = -EFAULT; + goto out; + } + + kvm->arch.guest_pmap[gfn] = pfn; +out: + srcu_read_unlock(&kvm->srcu, srcu_idx); + return err; +} + +/* Translate guest KSEG0 addresses to Host PA */ +unsigned long kvm_mips_translate_guest_kseg0_to_hpa(struct kvm_vcpu *vcpu, + unsigned long gva) +{ + gfn_t gfn; + unsigned long offset = gva & ~PAGE_MASK; + struct kvm *kvm = vcpu->kvm; + + if (KVM_GUEST_KSEGX(gva) != KVM_GUEST_KSEG0) { + kvm_err("%s/%p: Invalid gva: %#lx\n", __func__, + __builtin_return_address(0), gva); + return KVM_INVALID_PAGE; + } + + gfn = (KVM_GUEST_CPHYSADDR(gva) >> PAGE_SHIFT); + + if (gfn >= kvm->arch.guest_pmap_npages) { + kvm_err("%s: Invalid gfn: %#llx, GVA: %#lx\n", __func__, gfn, + gva); + return KVM_INVALID_PAGE; + } + + if (kvm_mips_map_page(vcpu->kvm, gfn) < 0) + return KVM_INVALID_ADDR; + + return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset; +} + +/* XXXKYMA: Must be called with interrupts disabled */ +int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr, + struct kvm_vcpu *vcpu) +{ + gfn_t gfn; + kvm_pfn_t pfn0, pfn1; + unsigned long vaddr = 0; + unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0; + struct kvm *kvm = vcpu->kvm; + const int flush_dcache_mask = 0; + int ret; + + if (KVM_GUEST_KSEGX(badvaddr) != KVM_GUEST_KSEG0) { + kvm_err("%s: Invalid BadVaddr: %#lx\n", __func__, badvaddr); + kvm_mips_dump_host_tlbs(); + return -1; + } + + gfn = (KVM_GUEST_CPHYSADDR(badvaddr) >> PAGE_SHIFT); + if ((gfn | 1) >= kvm->arch.guest_pmap_npages) { + kvm_err("%s: Invalid gfn: %#llx, BadVaddr: %#lx\n", __func__, + gfn, badvaddr); + kvm_mips_dump_host_tlbs(); + return -1; + } + vaddr = badvaddr & (PAGE_MASK << 1); + + if (kvm_mips_map_page(vcpu->kvm, gfn) < 0) + return -1; + + if (kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1) < 0) + return -1; + + pfn0 = kvm->arch.guest_pmap[gfn & ~0x1]; + pfn1 = kvm->arch.guest_pmap[gfn | 0x1]; + + entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) | + ((_page_cachable_default >> _CACHE_SHIFT) << ENTRYLO_C_SHIFT) | + ENTRYLO_D | ENTRYLO_V; + entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) | + ((_page_cachable_default >> _CACHE_SHIFT) << ENTRYLO_C_SHIFT) | + ENTRYLO_D | ENTRYLO_V; + + preempt_disable(); + entryhi = (vaddr | kvm_mips_get_kernel_asid(vcpu)); + ret = kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1, + flush_dcache_mask); + preempt_enable(); + + return ret; +} + +int kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu, + struct kvm_mips_tlb *tlb) +{ + unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0; + struct kvm *kvm = vcpu->kvm; + kvm_pfn_t pfn0, pfn1; + gfn_t gfn0, gfn1; + long tlb_lo[2]; + int ret; + + tlb_lo[0] = tlb->tlb_lo[0]; + tlb_lo[1] = tlb->tlb_lo[1]; + + /* + * The commpage address must not be mapped to anything else if the guest + * TLB contains entries nearby, or commpage accesses will break. + */ + if (!((tlb->tlb_hi ^ KVM_GUEST_COMMPAGE_ADDR) & + VPN2_MASK & (PAGE_MASK << 1))) + tlb_lo[(KVM_GUEST_COMMPAGE_ADDR >> PAGE_SHIFT) & 1] = 0; + + gfn0 = mips3_tlbpfn_to_paddr(tlb_lo[0]) >> PAGE_SHIFT; + gfn1 = mips3_tlbpfn_to_paddr(tlb_lo[1]) >> PAGE_SHIFT; + if (gfn0 >= kvm->arch.guest_pmap_npages || + gfn1 >= kvm->arch.guest_pmap_npages) { + kvm_err("%s: Invalid gfn: [%#llx, %#llx], EHi: %#lx\n", + __func__, gfn0, gfn1, tlb->tlb_hi); + kvm_mips_dump_guest_tlbs(vcpu); + return -1; + } + + if (kvm_mips_map_page(kvm, gfn0) < 0) + return -1; + + if (kvm_mips_map_page(kvm, gfn1) < 0) + return -1; + + pfn0 = kvm->arch.guest_pmap[gfn0]; + pfn1 = kvm->arch.guest_pmap[gfn1]; + + /* Get attributes from the Guest TLB */ + entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) | + ((_page_cachable_default >> _CACHE_SHIFT) << ENTRYLO_C_SHIFT) | + (tlb_lo[0] & ENTRYLO_D) | + (tlb_lo[0] & ENTRYLO_V); + entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) | + ((_page_cachable_default >> _CACHE_SHIFT) << ENTRYLO_C_SHIFT) | + (tlb_lo[1] & ENTRYLO_D) | + (tlb_lo[1] & ENTRYLO_V); + + kvm_debug("@ %#lx tlb_lo0: 0x%08lx tlb_lo1: 0x%08lx\n", vcpu->arch.pc, + tlb->tlb_lo[0], tlb->tlb_lo[1]); + + preempt_disable(); + entryhi = (tlb->tlb_hi & VPN2_MASK) | (KVM_GUEST_KERNEL_MODE(vcpu) ? + kvm_mips_get_kernel_asid(vcpu) : + kvm_mips_get_user_asid(vcpu)); + ret = kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1, + tlb->tlb_mask); + preempt_enable(); + + return ret; +} + +void kvm_get_new_mmu_context(struct mm_struct *mm, unsigned long cpu, + struct kvm_vcpu *vcpu) +{ + unsigned long asid = asid_cache(cpu); + + asid += cpu_asid_inc(); + if (!(asid & cpu_asid_mask(&cpu_data[cpu]))) { + if (cpu_has_vtag_icache) + flush_icache_all(); + + kvm_local_flush_tlb_all(); /* start new asid cycle */ + + if (!asid) /* fix version if needed */ + asid = asid_first_version(cpu); + } + + cpu_context(cpu, mm) = asid_cache(cpu) = asid; +} + +/** + * kvm_mips_migrate_count() - Migrate timer. + * @vcpu: Virtual CPU. + * + * Migrate CP0_Count hrtimer to the current CPU by cancelling and restarting it + * if it was running prior to being cancelled. + * + * Must be called when the VCPU is migrated to a different CPU to ensure that + * timer expiry during guest execution interrupts the guest and causes the + * interrupt to be delivered in a timely manner. + */ +static void kvm_mips_migrate_count(struct kvm_vcpu *vcpu) +{ + if (hrtimer_cancel(&vcpu->arch.comparecount_timer)) + hrtimer_restart(&vcpu->arch.comparecount_timer); +} + +/* Restore ASID once we are scheduled back after preemption */ +void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) +{ + unsigned long asid_mask = cpu_asid_mask(&cpu_data[cpu]); + unsigned long flags; + int newasid = 0; + + kvm_debug("%s: vcpu %p, cpu: %d\n", __func__, vcpu, cpu); + + /* Allocate new kernel and user ASIDs if needed */ + + local_irq_save(flags); + + if ((vcpu->arch.guest_kernel_asid[cpu] ^ asid_cache(cpu)) & + asid_version_mask(cpu)) { + kvm_get_new_mmu_context(&vcpu->arch.guest_kernel_mm, cpu, vcpu); + vcpu->arch.guest_kernel_asid[cpu] = + vcpu->arch.guest_kernel_mm.context.asid[cpu]; + kvm_get_new_mmu_context(&vcpu->arch.guest_user_mm, cpu, vcpu); + vcpu->arch.guest_user_asid[cpu] = + vcpu->arch.guest_user_mm.context.asid[cpu]; + newasid++; + + kvm_debug("[%d]: cpu_context: %#lx\n", cpu, + cpu_context(cpu, current->mm)); + kvm_debug("[%d]: Allocated new ASID for Guest Kernel: %#x\n", + cpu, vcpu->arch.guest_kernel_asid[cpu]); + kvm_debug("[%d]: Allocated new ASID for Guest User: %#x\n", cpu, + vcpu->arch.guest_user_asid[cpu]); + } + + if (vcpu->arch.last_sched_cpu != cpu) { + kvm_debug("[%d->%d]KVM VCPU[%d] switch\n", + vcpu->arch.last_sched_cpu, cpu, vcpu->vcpu_id); + /* + * Migrate the timer interrupt to the current CPU so that it + * always interrupts the guest and synchronously triggers a + * guest timer interrupt. + */ + kvm_mips_migrate_count(vcpu); + } + + if (!newasid) { + /* + * If we preempted while the guest was executing, then reload + * the pre-empted ASID + */ + if (current->flags & PF_VCPU) { + write_c0_entryhi(vcpu->arch. + preempt_entryhi & asid_mask); + ehb(); + } + } else { + /* New ASIDs were allocated for the VM */ + + /* + * Were we in guest context? If so then the pre-empted ASID is + * no longer valid, we need to set it to what it should be based + * on the mode of the Guest (Kernel/User) + */ + if (current->flags & PF_VCPU) { + if (KVM_GUEST_KERNEL_MODE(vcpu)) + write_c0_entryhi(vcpu->arch. + guest_kernel_asid[cpu] & + asid_mask); + else + write_c0_entryhi(vcpu->arch. + guest_user_asid[cpu] & + asid_mask); + ehb(); + } + } + + /* restore guest state to registers */ + kvm_mips_callbacks->vcpu_set_regs(vcpu); + + local_irq_restore(flags); + +} + +/* ASID can change if another task is scheduled during preemption */ +void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) +{ + unsigned long flags; + int cpu; + + local_irq_save(flags); + + cpu = smp_processor_id(); + + vcpu->arch.preempt_entryhi = read_c0_entryhi(); + vcpu->arch.last_sched_cpu = cpu; + + /* save guest state in registers */ + kvm_mips_callbacks->vcpu_get_regs(vcpu); + + if (((cpu_context(cpu, current->mm) ^ asid_cache(cpu)) & + asid_version_mask(cpu))) { + kvm_debug("%s: Dropping MMU Context: %#lx\n", __func__, + cpu_context(cpu, current->mm)); + drop_mmu_context(current->mm, cpu); + } + write_c0_entryhi(cpu_asid(cpu, current->mm)); + ehb(); + + local_irq_restore(flags); +} + +u32 kvm_get_inst(u32 *opc, struct kvm_vcpu *vcpu) +{ + struct mips_coproc *cop0 = vcpu->arch.cop0; + unsigned long paddr, flags, vpn2, asid; + unsigned long va = (unsigned long)opc; + void *vaddr; + u32 inst; + int index; + + if (KVM_GUEST_KSEGX(va) < KVM_GUEST_KSEG0 || + KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG23) { + local_irq_save(flags); + index = kvm_mips_host_tlb_lookup(vcpu, va); + if (index >= 0) { + inst = *(opc); + } else { + vpn2 = va & VPN2_MASK; + asid = kvm_read_c0_guest_entryhi(cop0) & + KVM_ENTRYHI_ASID; + index = kvm_mips_guest_tlb_lookup(vcpu, vpn2 | asid); + if (index < 0) { + kvm_err("%s: get_user_failed for %p, vcpu: %p, ASID: %#lx\n", + __func__, opc, vcpu, read_c0_entryhi()); + kvm_mips_dump_host_tlbs(); + kvm_mips_dump_guest_tlbs(vcpu); + local_irq_restore(flags); + return KVM_INVALID_INST; + } + if (kvm_mips_handle_mapped_seg_tlb_fault(vcpu, + &vcpu->arch.guest_tlb[index])) { + kvm_err("%s: handling mapped seg tlb fault failed for %p, index: %u, vcpu: %p, ASID: %#lx\n", + __func__, opc, index, vcpu, + read_c0_entryhi()); + kvm_mips_dump_guest_tlbs(vcpu); + local_irq_restore(flags); + return KVM_INVALID_INST; + } + inst = *(opc); + } + local_irq_restore(flags); + } else if (KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG0) { + paddr = kvm_mips_translate_guest_kseg0_to_hpa(vcpu, va); + vaddr = kmap_atomic(pfn_to_page(PHYS_PFN(paddr))); + vaddr += paddr & ~PAGE_MASK; + inst = *(u32 *)vaddr; + kunmap_atomic(vaddr); + } else { + kvm_err("%s: illegal address: %p\n", __func__, opc); + return KVM_INVALID_INST; + } + + return inst; +} -- cgit v1.2.3-54-g00ecf