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-rw-r--r--arch/mips/kvm/mmu.c375
1 files changed, 375 insertions, 0 deletions
diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c
new file mode 100644
index 000000000000..57319ee57c4f
--- /dev/null
+++ b/arch/mips/kvm/mmu.c
@@ -0,0 +1,375 @@
+/*
+ * 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 <sanjayl@kymasys.com>
+ */
+
+#include <linux/highmem.h>
+#include <linux/kvm_host.h>
+#include <asm/mmu_context.h>
+
+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_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 >= 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;
+ int ret;
+
+ if ((tlb->tlb_hi & VPN2_MASK) == 0) {
+ pfn0 = 0;
+ pfn1 = 0;
+ } else {
+ if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo[0])
+ >> PAGE_SHIFT) < 0)
+ return -1;
+
+ if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo[1])
+ >> PAGE_SHIFT) < 0)
+ return -1;
+
+ pfn0 = kvm->arch.guest_pmap[
+ mips3_tlbpfn_to_paddr(tlb->tlb_lo[0]) >> PAGE_SHIFT];
+ pfn1 = kvm->arch.guest_pmap[
+ mips3_tlbpfn_to_paddr(tlb->tlb_lo[1]) >> PAGE_SHIFT];
+ }
+
+ /* Get attributes from the Guest TLB */
+ entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) |
+ ((_page_cachable_default >> _CACHE_SHIFT) << ENTRYLO_C_SHIFT) |
+ (tlb->tlb_lo[0] & ENTRYLO_D) |
+ (tlb->tlb_lo[0] & ENTRYLO_V);
+ entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) |
+ ((_page_cachable_default >> _CACHE_SHIFT) << ENTRYLO_C_SHIFT) |
+ (tlb->tlb_lo[1] & ENTRYLO_D) |
+ (tlb->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;
+ }
+ kvm_mips_handle_mapped_seg_tlb_fault(vcpu,
+ &vcpu->arch.
+ guest_tlb[index]);
+ 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;
+}
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