book3s.c

Go to the documentation of this file.

/*
 * Copyright (C) 2009. SUSE Linux Products GmbH. All rights reserved.
 *
 * Authors:
 *    Alexander Graf <[email protected]>
 *    Kevin Wolf <[email protected]>
 *
 * Description:
 * This file is derived from arch/powerpc/kvm/44x.c,
 * by Hollis Blanchard <[email protected]>.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation.
 */

#include <linux/kvm_host.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/slab.h>

#include <asm/reg.h>
#include <asm/cputable.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
#include <asm/mmu_context.h>
#include <asm/page.h>
#include <linux/gfp.h>
#include <linux/sched.h>
#include <linux/vmalloc.h>
#include <linux/highmem.h>

#include "trace.h"

#define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU

/* #define EXIT_DEBUG */

struct kvm_stats_debugfs_item debugfs_entries[] = {
    { "exits",       VCPU_STAT(sum_exits) },
    { "mmio",        VCPU_STAT(mmio_exits) },
    { "sig",         VCPU_STAT(signal_exits) },
    { "sysc",        VCPU_STAT(syscall_exits) },
    { "inst_emu",    VCPU_STAT(emulated_inst_exits) },
    { "dec",         VCPU_STAT(dec_exits) },
    { "ext_intr",    VCPU_STAT(ext_intr_exits) },
    { "queue_intr",  VCPU_STAT(queue_intr) },
    { "halt_wakeup", VCPU_STAT(halt_wakeup) },
    { "pf_storage",  VCPU_STAT(pf_storage) },
    { "sp_storage",  VCPU_STAT(sp_storage) },
    { "pf_instruc",  VCPU_STAT(pf_instruc) },
    { "sp_instruc",  VCPU_STAT(sp_instruc) },
    { "ld",          VCPU_STAT(ld) },
    { "ld_slow",     VCPU_STAT(ld_slow) },
    { "st",          VCPU_STAT(st) },
    { "st_slow",     VCPU_STAT(st_slow) },
    { NULL }
};

void kvmppc_core_load_host_debugstate(struct kvm_vcpu *vcpu)
{
}

void kvmppc_core_load_guest_debugstate(struct kvm_vcpu *vcpu)
{
}

void kvmppc_inject_interrupt(struct kvm_vcpu *vcpu, int vec, u64 flags)
{
    vcpu->arch.shared->srr0 = kvmppc_get_pc(vcpu);
    vcpu->arch.shared->srr1 = vcpu->arch.shared->msr | flags;
    kvmppc_set_pc(vcpu, kvmppc_interrupt_offset(vcpu) + vec);
    vcpu->arch.mmu.reset_msr(vcpu);
}

static int kvmppc_book3s_vec2irqprio(unsigned int vec)
{
    unsigned int prio;

    switch (vec) {
    case 0x100: prio = BOOK3S_IRQPRIO_SYSTEM_RESET;     break;
    case 0x200: prio = BOOK3S_IRQPRIO_MACHINE_CHECK;    break;
    case 0x300: prio = BOOK3S_IRQPRIO_DATA_STORAGE;     break;
    case 0x380: prio = BOOK3S_IRQPRIO_DATA_SEGMENT;     break;
    case 0x400: prio = BOOK3S_IRQPRIO_INST_STORAGE;     break;
    case 0x480: prio = BOOK3S_IRQPRIO_INST_SEGMENT;     break;
    case 0x500: prio = BOOK3S_IRQPRIO_EXTERNAL;     break;
    case 0x501: prio = BOOK3S_IRQPRIO_EXTERNAL_LEVEL;   break;
    case 0x600: prio = BOOK3S_IRQPRIO_ALIGNMENT;        break;
    case 0x700: prio = BOOK3S_IRQPRIO_PROGRAM;      break;
    case 0x800: prio = BOOK3S_IRQPRIO_FP_UNAVAIL;       break;
    case 0x900: prio = BOOK3S_IRQPRIO_DECREMENTER;      break;
    case 0xc00: prio = BOOK3S_IRQPRIO_SYSCALL;      break;
    case 0xd00: prio = BOOK3S_IRQPRIO_DEBUG;        break;
    case 0xf20: prio = BOOK3S_IRQPRIO_ALTIVEC;      break;
    case 0xf40: prio = BOOK3S_IRQPRIO_VSX;          break;
    default:    prio = BOOK3S_IRQPRIO_MAX;          break;
    }

    return prio;
}

static void kvmppc_book3s_dequeue_irqprio(struct kvm_vcpu *vcpu,
                      unsigned int vec)
{
    unsigned long old_pending = vcpu->arch.pending_exceptions;

    clear_bit(kvmppc_book3s_vec2irqprio(vec),
          &vcpu->arch.pending_exceptions);

    kvmppc_update_int_pending(vcpu, vcpu->arch.pending_exceptions,
                  old_pending);
}

void kvmppc_book3s_queue_irqprio(struct kvm_vcpu *vcpu, unsigned int vec)
{
    vcpu->stat.queue_intr++;

    set_bit(kvmppc_book3s_vec2irqprio(vec),
        &vcpu->arch.pending_exceptions);
#ifdef EXIT_DEBUG
    printk(KERN_INFO "Queueing interrupt %x\n", vec);
#endif
}


void kvmppc_core_queue_program(struct kvm_vcpu *vcpu, ulong flags)
{
    /* might as well deliver this straight away */
    kvmppc_inject_interrupt(vcpu, BOOK3S_INTERRUPT_PROGRAM, flags);
}

void kvmppc_core_queue_dec(struct kvm_vcpu *vcpu)
{
    kvmppc_book3s_queue_irqprio(vcpu, BOOK3S_INTERRUPT_DECREMENTER);
}

int kvmppc_core_pending_dec(struct kvm_vcpu *vcpu)
{
    return test_bit(BOOK3S_IRQPRIO_DECREMENTER, &vcpu->arch.pending_exceptions);
}

void kvmppc_core_dequeue_dec(struct kvm_vcpu *vcpu)
{
    kvmppc_book3s_dequeue_irqprio(vcpu, BOOK3S_INTERRUPT_DECREMENTER);
}

void kvmppc_core_queue_external(struct kvm_vcpu *vcpu,
                                struct kvm_interrupt *irq)
{
    unsigned int vec = BOOK3S_INTERRUPT_EXTERNAL;

    if (irq->irq == KVM_INTERRUPT_SET_LEVEL)
        vec = BOOK3S_INTERRUPT_EXTERNAL_LEVEL;

    kvmppc_book3s_queue_irqprio(vcpu, vec);
}

void kvmppc_core_dequeue_external(struct kvm_vcpu *vcpu,
                                  struct kvm_interrupt *irq)
{
    kvmppc_book3s_dequeue_irqprio(vcpu, BOOK3S_INTERRUPT_EXTERNAL);
    kvmppc_book3s_dequeue_irqprio(vcpu, BOOK3S_INTERRUPT_EXTERNAL_LEVEL);
}

int kvmppc_book3s_irqprio_deliver(struct kvm_vcpu *vcpu, unsigned int priority)
{
    int deliver = 1;
    int vec = 0;
    bool crit = kvmppc_critical_section(vcpu);

    switch (priority) {
    case BOOK3S_IRQPRIO_DECREMENTER:
        deliver = (vcpu->arch.shared->msr & MSR_EE) && !crit;
        vec = BOOK3S_INTERRUPT_DECREMENTER;
        break;
    case BOOK3S_IRQPRIO_EXTERNAL:
    case BOOK3S_IRQPRIO_EXTERNAL_LEVEL:
        deliver = (vcpu->arch.shared->msr & MSR_EE) && !crit;
        vec = BOOK3S_INTERRUPT_EXTERNAL;
        break;
    case BOOK3S_IRQPRIO_SYSTEM_RESET:
        vec = BOOK3S_INTERRUPT_SYSTEM_RESET;
        break;
    case BOOK3S_IRQPRIO_MACHINE_CHECK:
        vec = BOOK3S_INTERRUPT_MACHINE_CHECK;
        break;
    case BOOK3S_IRQPRIO_DATA_STORAGE:
        vec = BOOK3S_INTERRUPT_DATA_STORAGE;
        break;
    case BOOK3S_IRQPRIO_INST_STORAGE:
        vec = BOOK3S_INTERRUPT_INST_STORAGE;
        break;
    case BOOK3S_IRQPRIO_DATA_SEGMENT:
        vec = BOOK3S_INTERRUPT_DATA_SEGMENT;
        break;
    case BOOK3S_IRQPRIO_INST_SEGMENT:
        vec = BOOK3S_INTERRUPT_INST_SEGMENT;
        break;
    case BOOK3S_IRQPRIO_ALIGNMENT:
        vec = BOOK3S_INTERRUPT_ALIGNMENT;
        break;
    case BOOK3S_IRQPRIO_PROGRAM:
        vec = BOOK3S_INTERRUPT_PROGRAM;
        break;
    case BOOK3S_IRQPRIO_VSX:
        vec = BOOK3S_INTERRUPT_VSX;
        break;
    case BOOK3S_IRQPRIO_ALTIVEC:
        vec = BOOK3S_INTERRUPT_ALTIVEC;
        break;
    case BOOK3S_IRQPRIO_FP_UNAVAIL:
        vec = BOOK3S_INTERRUPT_FP_UNAVAIL;
        break;
    case BOOK3S_IRQPRIO_SYSCALL:
        vec = BOOK3S_INTERRUPT_SYSCALL;
        break;
    case BOOK3S_IRQPRIO_DEBUG:
        vec = BOOK3S_INTERRUPT_TRACE;
        break;
    case BOOK3S_IRQPRIO_PERFORMANCE_MONITOR:
        vec = BOOK3S_INTERRUPT_PERFMON;
        break;
    default:
        deliver = 0;
        printk(KERN_ERR "KVM: Unknown interrupt: 0x%x\n", priority);
        break;
    }

#if 0
    printk(KERN_INFO "Deliver interrupt 0x%x? %x\n", vec, deliver);
#endif

    if (deliver)
        kvmppc_inject_interrupt(vcpu, vec, 0);

    return deliver;
}

/*
 * This function determines if an irqprio should be cleared once issued.
 */
static bool clear_irqprio(struct kvm_vcpu *vcpu, unsigned int priority)
{
    switch (priority) {
        case BOOK3S_IRQPRIO_DECREMENTER:
            /* DEC interrupts get cleared by mtdec */
            return false;
        case BOOK3S_IRQPRIO_EXTERNAL_LEVEL:
            /* External interrupts get cleared by userspace */
            return false;
    }

    return true;
}

int kvmppc_core_prepare_to_enter(struct kvm_vcpu *vcpu)
{
    unsigned long *pending = &vcpu->arch.pending_exceptions;
    unsigned long old_pending = vcpu->arch.pending_exceptions;
    unsigned int priority;

#ifdef EXIT_DEBUG
    if (vcpu->arch.pending_exceptions)
        printk(KERN_EMERG "KVM: Check pending: %lx\n", vcpu->arch.pending_exceptions);
#endif
    priority = __ffs(*pending);
    while (priority < BOOK3S_IRQPRIO_MAX) {
        if (kvmppc_book3s_irqprio_deliver(vcpu, priority) &&
            clear_irqprio(vcpu, priority)) {
            clear_bit(priority, &vcpu->arch.pending_exceptions);
            break;
        }

        priority = find_next_bit(pending,
                     BITS_PER_BYTE * sizeof(*pending),
                     priority + 1);
    }

    /* Tell the guest about our interrupt status */
    kvmppc_update_int_pending(vcpu, *pending, old_pending);

    return 0;
}

pfn_t kvmppc_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn)
{
    ulong mp_pa = vcpu->arch.magic_page_pa;

    if (!(vcpu->arch.shared->msr & MSR_SF))
        mp_pa = (uint32_t)mp_pa;

    /* Magic page override */
    if (unlikely(mp_pa) &&
        unlikely(((gfn << PAGE_SHIFT) & KVM_PAM) ==
             ((mp_pa & PAGE_MASK) & KVM_PAM))) {
        ulong shared_page = ((ulong)vcpu->arch.shared) & PAGE_MASK;
        pfn_t pfn;

        pfn = (pfn_t)virt_to_phys((void*)shared_page) >> PAGE_SHIFT;
        get_page(pfn_to_page(pfn));
        return pfn;
    }

    return gfn_to_pfn(vcpu->kvm, gfn);
}

static int kvmppc_xlate(struct kvm_vcpu *vcpu, ulong eaddr, bool data,
             struct kvmppc_pte *pte)
{
    int relocated = (vcpu->arch.shared->msr & (data ? MSR_DR : MSR_IR));
    int r;

    if (relocated) {
        r = vcpu->arch.mmu.xlate(vcpu, eaddr, pte, data);
    } else {
        pte->eaddr = eaddr;
        pte->raddr = eaddr & KVM_PAM;
        pte->vpage = VSID_REAL | eaddr >> 12;
        pte->may_read = true;
        pte->may_write = true;
        pte->may_execute = true;
        r = 0;
    }

    return r;
}

static hva_t kvmppc_bad_hva(void)
{
    return PAGE_OFFSET;
}

static hva_t kvmppc_pte_to_hva(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte,
                   bool read)
{
    hva_t hpage;

    if (read && !pte->may_read)
        goto err;

    if (!read && !pte->may_write)
        goto err;

    hpage = gfn_to_hva(vcpu->kvm, pte->raddr >> PAGE_SHIFT);
    if (kvm_is_error_hva(hpage))
        goto err;

    return hpage | (pte->raddr & ~PAGE_MASK);
err:
    return kvmppc_bad_hva();
}

int kvmppc_st(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr,
          bool data)
{
    struct kvmppc_pte pte;

    vcpu->stat.st++;

    if (kvmppc_xlate(vcpu, *eaddr, data, &pte))
        return -ENOENT;

    *eaddr = pte.raddr;

    if (!pte.may_write)
        return -EPERM;

    if (kvm_write_guest(vcpu->kvm, pte.raddr, ptr, size))
        return EMULATE_DO_MMIO;

    return EMULATE_DONE;
}

int kvmppc_ld(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr,
              bool data)
{
    struct kvmppc_pte pte;
    hva_t hva = *eaddr;

    vcpu->stat.ld++;

    if (kvmppc_xlate(vcpu, *eaddr, data, &pte))
        goto nopte;

    *eaddr = pte.raddr;

    hva = kvmppc_pte_to_hva(vcpu, &pte, true);
    if (kvm_is_error_hva(hva))
        goto mmio;

    if (copy_from_user(ptr, (void __user *)hva, size)) {
        printk(KERN_INFO "kvmppc_ld at 0x%lx failed\n", hva);
        goto mmio;
    }

    return EMULATE_DONE;

nopte:
    return -ENOENT;
mmio:
    return EMULATE_DO_MMIO;
}

int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
{
    return 0;
}

int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
    int i;

    regs->pc = kvmppc_get_pc(vcpu);
    regs->cr = kvmppc_get_cr(vcpu);
    regs->ctr = kvmppc_get_ctr(vcpu);
    regs->lr = kvmppc_get_lr(vcpu);
    regs->xer = kvmppc_get_xer(vcpu);
    regs->msr = vcpu->arch.shared->msr;
    regs->srr0 = vcpu->arch.shared->srr0;
    regs->srr1 = vcpu->arch.shared->srr1;
    regs->pid = vcpu->arch.pid;
    regs->sprg0 = vcpu->arch.shared->sprg0;
    regs->sprg1 = vcpu->arch.shared->sprg1;
    regs->sprg2 = vcpu->arch.shared->sprg2;
    regs->sprg3 = vcpu->arch.shared->sprg3;
    regs->sprg4 = vcpu->arch.shared->sprg4;
    regs->sprg5 = vcpu->arch.shared->sprg5;
    regs->sprg6 = vcpu->arch.shared->sprg6;
    regs->sprg7 = vcpu->arch.shared->sprg7;

    for (i = 0; i < ARRAY_SIZE(regs->gpr); i++)
        regs->gpr[i] = kvmppc_get_gpr(vcpu, i);

    return 0;
}

int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
    int i;

    kvmppc_set_pc(vcpu, regs->pc);
    kvmppc_set_cr(vcpu, regs->cr);
    kvmppc_set_ctr(vcpu, regs->ctr);
    kvmppc_set_lr(vcpu, regs->lr);
    kvmppc_set_xer(vcpu, regs->xer);
    kvmppc_set_msr(vcpu, regs->msr);
    vcpu->arch.shared->srr0 = regs->srr0;
    vcpu->arch.shared->srr1 = regs->srr1;
    vcpu->arch.shared->sprg0 = regs->sprg0;
    vcpu->arch.shared->sprg1 = regs->sprg1;
    vcpu->arch.shared->sprg2 = regs->sprg2;
    vcpu->arch.shared->sprg3 = regs->sprg3;
    vcpu->arch.shared->sprg4 = regs->sprg4;
    vcpu->arch.shared->sprg5 = regs->sprg5;
    vcpu->arch.shared->sprg6 = regs->sprg6;
    vcpu->arch.shared->sprg7 = regs->sprg7;

    for (i = 0; i < ARRAY_SIZE(regs->gpr); i++)
        kvmppc_set_gpr(vcpu, i, regs->gpr[i]);

    return 0;
}

int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
    return -ENOTSUPP;
}

int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
    return -ENOTSUPP;
}

int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
                                  struct kvm_translation *tr)
{
    return 0;
}

void kvmppc_decrementer_func(unsigned long data)
{
    struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;

    kvmppc_core_queue_dec(vcpu);
    kvm_vcpu_kick(vcpu);
}