USB: convert drivers/media/* to use module_usb_driver()

[zen-stable.git] / arch / powerpc / kvm / book3s_hv.c

/*
 * Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
 * Copyright (C) 2009. SUSE Linux Products GmbH. All rights reserved.
 *
 * Authors:
 *    Paul Mackerras <paulus@au1.ibm.com>
 *    Alexander Graf <agraf@suse.de>
 *    Kevin Wolf <mail@kevin-wolf.de>
 *
 * Description: KVM functions specific to running on Book 3S
 * processors in hypervisor mode (specifically POWER7 and later).
 *
 * This file is derived from arch/powerpc/kvm/book3s.c,
 * by Alexander Graf <agraf@suse.de>.
 *
 * 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/slab.h>
#include <linux/preempt.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/export.h>
#include <linux/fs.h>
#include <linux/anon_inodes.h>
#include <linux/cpumask.h>
#include <linux/spinlock.h>
#include <linux/page-flags.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/lppaca.h>
#include <asm/processor.h>
#include <asm/cputhreads.h>
#include <asm/page.h>
#include <linux/gfp.h>
#include <linux/sched.h>
#include <linux/vmalloc.h>
#include <linux/highmem.h>

/*
 * For now, limit memory to 64GB and require it to be large pages.
 * This value is chosen because it makes the ram_pginfo array be
 * 64kB in size, which is about as large as we want to be trying
 * to allocate with kmalloc.
 */
#define MAX_MEM_ORDER           36

#define LARGE_PAGE_ORDER        24      /* 16MB pages */

/* #define EXIT_DEBUG */
/* #define EXIT_DEBUG_SIMPLE */
/* #define EXIT_DEBUG_INT */

static void kvmppc_end_cede(struct kvm_vcpu *vcpu);

void kvmppc_core_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
        local_paca->kvm_hstate.kvm_vcpu = vcpu;
        local_paca->kvm_hstate.kvm_vcore = vcpu->arch.vcore;
}

void kvmppc_core_vcpu_put(struct kvm_vcpu *vcpu)
{
}

void kvmppc_set_msr(struct kvm_vcpu *vcpu, u64 msr)
{
        vcpu->arch.shregs.msr = msr;
        kvmppc_end_cede(vcpu);
}

void kvmppc_set_pvr(struct kvm_vcpu *vcpu, u32 pvr)
{
        vcpu->arch.pvr = pvr;
}

void kvmppc_dump_regs(struct kvm_vcpu *vcpu)
{
        int r;

        pr_err("vcpu %p (%d):\n", vcpu, vcpu->vcpu_id);
        pr_err("pc  = %.16lx  msr = %.16llx  trap = %x\n",
               vcpu->arch.pc, vcpu->arch.shregs.msr, vcpu->arch.trap);
        for (r = 0; r < 16; ++r)
                pr_err("r%2d = %.16lx  r%d = %.16lx\n",
                       r, kvmppc_get_gpr(vcpu, r),
                       r+16, kvmppc_get_gpr(vcpu, r+16));
        pr_err("ctr = %.16lx  lr  = %.16lx\n",
               vcpu->arch.ctr, vcpu->arch.lr);
        pr_err("srr0 = %.16llx srr1 = %.16llx\n",
               vcpu->arch.shregs.srr0, vcpu->arch.shregs.srr1);
        pr_err("sprg0 = %.16llx sprg1 = %.16llx\n",
               vcpu->arch.shregs.sprg0, vcpu->arch.shregs.sprg1);
        pr_err("sprg2 = %.16llx sprg3 = %.16llx\n",
               vcpu->arch.shregs.sprg2, vcpu->arch.shregs.sprg3);
        pr_err("cr = %.8x  xer = %.16lx  dsisr = %.8x\n",
               vcpu->arch.cr, vcpu->arch.xer, vcpu->arch.shregs.dsisr);
        pr_err("dar = %.16llx\n", vcpu->arch.shregs.dar);
        pr_err("fault dar = %.16lx dsisr = %.8x\n",
               vcpu->arch.fault_dar, vcpu->arch.fault_dsisr);
        pr_err("SLB (%d entries):\n", vcpu->arch.slb_max);
        for (r = 0; r < vcpu->arch.slb_max; ++r)
                pr_err("  ESID = %.16llx VSID = %.16llx\n",
                       vcpu->arch.slb[r].orige, vcpu->arch.slb[r].origv);
        pr_err("lpcr = %.16lx sdr1 = %.16lx last_inst = %.8x\n",
               vcpu->kvm->arch.lpcr, vcpu->kvm->arch.sdr1,
               vcpu->arch.last_inst);
}

struct kvm_vcpu *kvmppc_find_vcpu(struct kvm *kvm, int id)
{
        int r;
        struct kvm_vcpu *v, *ret = NULL;

        mutex_lock(&kvm->lock);
        kvm_for_each_vcpu(r, v, kvm) {
                if (v->vcpu_id == id) {
                        ret = v;
                        break;
                }
        }
        mutex_unlock(&kvm->lock);
        return ret;
}

static void init_vpa(struct kvm_vcpu *vcpu, struct lppaca *vpa)
{
        vpa->shared_proc = 1;
        vpa->yield_count = 1;
}

static unsigned long do_h_register_vpa(struct kvm_vcpu *vcpu,
                                       unsigned long flags,
                                       unsigned long vcpuid, unsigned long vpa)
{
        struct kvm *kvm = vcpu->kvm;
        unsigned long pg_index, ra, len;
        unsigned long pg_offset;
        void *va;
        struct kvm_vcpu *tvcpu;

        tvcpu = kvmppc_find_vcpu(kvm, vcpuid);
        if (!tvcpu)
                return H_PARAMETER;

        flags >>= 63 - 18;
        flags &= 7;
        if (flags == 0 || flags == 4)
                return H_PARAMETER;
        if (flags < 4) {
                if (vpa & 0x7f)
                        return H_PARAMETER;
                /* registering new area; convert logical addr to real */
                pg_index = vpa >> kvm->arch.ram_porder;
                pg_offset = vpa & (kvm->arch.ram_psize - 1);
                if (pg_index >= kvm->arch.ram_npages)
                        return H_PARAMETER;
                if (kvm->arch.ram_pginfo[pg_index].pfn == 0)
                        return H_PARAMETER;
                ra = kvm->arch.ram_pginfo[pg_index].pfn << PAGE_SHIFT;
                ra |= pg_offset;
                va = __va(ra);
                if (flags <= 1)
                        len = *(unsigned short *)(va + 4);
                else
                        len = *(unsigned int *)(va + 4);
                if (pg_offset + len > kvm->arch.ram_psize)
                        return H_PARAMETER;
                switch (flags) {
                case 1:         /* register VPA */
                        if (len < 640)
                                return H_PARAMETER;
                        tvcpu->arch.vpa = va;
                        init_vpa(vcpu, va);
                        break;
                case 2:         /* register DTL */
                        if (len < 48)
                                return H_PARAMETER;
                        if (!tvcpu->arch.vpa)
                                return H_RESOURCE;
                        len -= len % 48;
                        tvcpu->arch.dtl = va;
                        tvcpu->arch.dtl_end = va + len;
                        break;
                case 3:         /* register SLB shadow buffer */
                        if (len < 8)
                                return H_PARAMETER;
                        if (!tvcpu->arch.vpa)
                                return H_RESOURCE;
                        tvcpu->arch.slb_shadow = va;
                        len = (len - 16) / 16;
                        tvcpu->arch.slb_shadow = va;
                        break;
                }
        } else {
                switch (flags) {
                case 5:         /* unregister VPA */
                        if (tvcpu->arch.slb_shadow || tvcpu->arch.dtl)
                                return H_RESOURCE;
                        tvcpu->arch.vpa = NULL;
                        break;
                case 6:         /* unregister DTL */
                        tvcpu->arch.dtl = NULL;
                        break;
                case 7:         /* unregister SLB shadow buffer */
                        tvcpu->arch.slb_shadow = NULL;
                        break;
                }
        }
        return H_SUCCESS;
}

int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
{
        unsigned long req = kvmppc_get_gpr(vcpu, 3);
        unsigned long target, ret = H_SUCCESS;
        struct kvm_vcpu *tvcpu;

        switch (req) {
        case H_CEDE:
                break;
        case H_PROD:
                target = kvmppc_get_gpr(vcpu, 4);
                tvcpu = kvmppc_find_vcpu(vcpu->kvm, target);
                if (!tvcpu) {
                        ret = H_PARAMETER;
                        break;
                }
                tvcpu->arch.prodded = 1;
                smp_mb();
                if (vcpu->arch.ceded) {
                        if (waitqueue_active(&vcpu->wq)) {
                                wake_up_interruptible(&vcpu->wq);
                                vcpu->stat.halt_wakeup++;
                        }
                }
                break;
        case H_CONFER:
                break;
        case H_REGISTER_VPA:
                ret = do_h_register_vpa(vcpu, kvmppc_get_gpr(vcpu, 4),
                                        kvmppc_get_gpr(vcpu, 5),
                                        kvmppc_get_gpr(vcpu, 6));
                break;
        default:
                return RESUME_HOST;
        }
        kvmppc_set_gpr(vcpu, 3, ret);
        vcpu->arch.hcall_needed = 0;
        return RESUME_GUEST;
}

static int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
                              struct task_struct *tsk)
{
        int r = RESUME_HOST;

        vcpu->stat.sum_exits++;

        run->exit_reason = KVM_EXIT_UNKNOWN;
        run->ready_for_interrupt_injection = 1;
        switch (vcpu->arch.trap) {
        /* We're good on these - the host merely wanted to get our attention */
        case BOOK3S_INTERRUPT_HV_DECREMENTER:
                vcpu->stat.dec_exits++;
                r = RESUME_GUEST;
                break;
        case BOOK3S_INTERRUPT_EXTERNAL:
                vcpu->stat.ext_intr_exits++;
                r = RESUME_GUEST;
                break;
        case BOOK3S_INTERRUPT_PERFMON:
                r = RESUME_GUEST;
                break;
        case BOOK3S_INTERRUPT_PROGRAM:
        {
                ulong flags;
                /*
                 * Normally program interrupts are delivered directly
                 * to the guest by the hardware, but we can get here
                 * as a result of a hypervisor emulation interrupt
                 * (e40) getting turned into a 700 by BML RTAS.
                 */
                flags = vcpu->arch.shregs.msr & 0x1f0000ull;
                kvmppc_core_queue_program(vcpu, flags);
                r = RESUME_GUEST;
                break;
        }
        case BOOK3S_INTERRUPT_SYSCALL:
        {
                /* hcall - punt to userspace */
                int i;

                if (vcpu->arch.shregs.msr & MSR_PR) {
                        /* sc 1 from userspace - reflect to guest syscall */
                        kvmppc_book3s_queue_irqprio(vcpu, BOOK3S_INTERRUPT_SYSCALL);
                        r = RESUME_GUEST;
                        break;
                }
                run->papr_hcall.nr = kvmppc_get_gpr(vcpu, 3);
                for (i = 0; i < 9; ++i)
                        run->papr_hcall.args[i] = kvmppc_get_gpr(vcpu, 4 + i);
                run->exit_reason = KVM_EXIT_PAPR_HCALL;
                vcpu->arch.hcall_needed = 1;
                r = RESUME_HOST;
                break;
        }
        /*
         * We get these next two if the guest does a bad real-mode access,
         * as we have enabled VRMA (virtualized real mode area) mode in the
         * LPCR.  We just generate an appropriate DSI/ISI to the guest.
         */
        case BOOK3S_INTERRUPT_H_DATA_STORAGE:
                vcpu->arch.shregs.dsisr = vcpu->arch.fault_dsisr;
                vcpu->arch.shregs.dar = vcpu->arch.fault_dar;
                kvmppc_inject_interrupt(vcpu, BOOK3S_INTERRUPT_DATA_STORAGE, 0);
                r = RESUME_GUEST;
                break;
        case BOOK3S_INTERRUPT_H_INST_STORAGE:
                kvmppc_inject_interrupt(vcpu, BOOK3S_INTERRUPT_INST_STORAGE,
                                        0x08000000);
                r = RESUME_GUEST;
                break;
        /*
         * This occurs if the guest executes an illegal instruction.
         * We just generate a program interrupt to the guest, since
         * we don't emulate any guest instructions at this stage.
         */
        case BOOK3S_INTERRUPT_H_EMUL_ASSIST:
                kvmppc_core_queue_program(vcpu, 0x80000);
                r = RESUME_GUEST;
                break;
        default:
                kvmppc_dump_regs(vcpu);
                printk(KERN_EMERG "trap=0x%x | pc=0x%lx | msr=0x%llx\n",
                        vcpu->arch.trap, kvmppc_get_pc(vcpu),
                        vcpu->arch.shregs.msr);
                r = RESUME_HOST;
                BUG();
                break;
        }

        return r;
}

int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
                                  struct kvm_sregs *sregs)
{
        int i;

        sregs->pvr = vcpu->arch.pvr;

        memset(sregs, 0, sizeof(struct kvm_sregs));
        for (i = 0; i < vcpu->arch.slb_max; i++) {
                sregs->u.s.ppc64.slb[i].slbe = vcpu->arch.slb[i].orige;
                sregs->u.s.ppc64.slb[i].slbv = vcpu->arch.slb[i].origv;
        }

        return 0;
}

int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
                                  struct kvm_sregs *sregs)
{
        int i, j;

        kvmppc_set_pvr(vcpu, sregs->pvr);

        j = 0;
        for (i = 0; i < vcpu->arch.slb_nr; i++) {
                if (sregs->u.s.ppc64.slb[i].slbe & SLB_ESID_V) {
                        vcpu->arch.slb[j].orige = sregs->u.s.ppc64.slb[i].slbe;
                        vcpu->arch.slb[j].origv = sregs->u.s.ppc64.slb[i].slbv;
                        ++j;
                }
        }
        vcpu->arch.slb_max = j;

        return 0;
}

int kvmppc_core_check_processor_compat(void)
{
        if (cpu_has_feature(CPU_FTR_HVMODE))
                return 0;
        return -EIO;
}

struct kvm_vcpu *kvmppc_core_vcpu_create(struct kvm *kvm, unsigned int id)
{
        struct kvm_vcpu *vcpu;
        int err = -EINVAL;
        int core;
        struct kvmppc_vcore *vcore;

        core = id / threads_per_core;
        if (core >= KVM_MAX_VCORES)
                goto out;

        err = -ENOMEM;
        vcpu = kzalloc(sizeof(struct kvm_vcpu), GFP_KERNEL);
        if (!vcpu)
                goto out;

        err = kvm_vcpu_init(vcpu, kvm, id);
        if (err)
                goto free_vcpu;

        vcpu->arch.shared = &vcpu->arch.shregs;
        vcpu->arch.last_cpu = -1;
        vcpu->arch.mmcr[0] = MMCR0_FC;
        vcpu->arch.ctrl = CTRL_RUNLATCH;
        /* default to host PVR, since we can't spoof it */
        vcpu->arch.pvr = mfspr(SPRN_PVR);
        kvmppc_set_pvr(vcpu, vcpu->arch.pvr);

        kvmppc_mmu_book3s_hv_init(vcpu);

        /*
         * We consider the vcpu stopped until we see the first run ioctl for it.
         */
        vcpu->arch.state = KVMPPC_VCPU_STOPPED;

        init_waitqueue_head(&vcpu->arch.cpu_run);

        mutex_lock(&kvm->lock);
        vcore = kvm->arch.vcores[core];
        if (!vcore) {
                vcore = kzalloc(sizeof(struct kvmppc_vcore), GFP_KERNEL);
                if (vcore) {
                        INIT_LIST_HEAD(&vcore->runnable_threads);
                        spin_lock_init(&vcore->lock);
                        init_waitqueue_head(&vcore->wq);
                }
                kvm->arch.vcores[core] = vcore;
        }
        mutex_unlock(&kvm->lock);

        if (!vcore)
                goto free_vcpu;

        spin_lock(&vcore->lock);
        ++vcore->num_threads;
        spin_unlock(&vcore->lock);
        vcpu->arch.vcore = vcore;

        vcpu->arch.cpu_type = KVM_CPU_3S_64;
        kvmppc_sanity_check(vcpu);

        return vcpu;

free_vcpu:
        kfree(vcpu);
out:
        return ERR_PTR(err);
}

void kvmppc_core_vcpu_free(struct kvm_vcpu *vcpu)
{
        kvm_vcpu_uninit(vcpu);
        kfree(vcpu);
}

static void kvmppc_set_timer(struct kvm_vcpu *vcpu)
{
        unsigned long dec_nsec, now;

        now = get_tb();
        if (now > vcpu->arch.dec_expires) {
                /* decrementer has already gone negative */
                kvmppc_core_queue_dec(vcpu);
                kvmppc_core_deliver_interrupts(vcpu);
                return;
        }
        dec_nsec = (vcpu->arch.dec_expires - now) * NSEC_PER_SEC
                   / tb_ticks_per_sec;
        hrtimer_start(&vcpu->arch.dec_timer, ktime_set(0, dec_nsec),
                      HRTIMER_MODE_REL);
        vcpu->arch.timer_running = 1;
}

static void kvmppc_end_cede(struct kvm_vcpu *vcpu)
{
        vcpu->arch.ceded = 0;
        if (vcpu->arch.timer_running) {
                hrtimer_try_to_cancel(&vcpu->arch.dec_timer);
                vcpu->arch.timer_running = 0;
        }
}

extern int __kvmppc_vcore_entry(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu);
extern void xics_wake_cpu(int cpu);

static void kvmppc_remove_runnable(struct kvmppc_vcore *vc,
                                   struct kvm_vcpu *vcpu)
{
        struct kvm_vcpu *v;

        if (vcpu->arch.state != KVMPPC_VCPU_RUNNABLE)
                return;
        vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST;
        --vc->n_runnable;
        ++vc->n_busy;
        /* decrement the physical thread id of each following vcpu */
        v = vcpu;
        list_for_each_entry_continue(v, &vc->runnable_threads, arch.run_list)
                --v->arch.ptid;
        list_del(&vcpu->arch.run_list);
}

static void kvmppc_start_thread(struct kvm_vcpu *vcpu)
{
        int cpu;
        struct paca_struct *tpaca;
        struct kvmppc_vcore *vc = vcpu->arch.vcore;

        if (vcpu->arch.timer_running) {
                hrtimer_try_to_cancel(&vcpu->arch.dec_timer);
                vcpu->arch.timer_running = 0;
        }
        cpu = vc->pcpu + vcpu->arch.ptid;
        tpaca = &paca[cpu];
        tpaca->kvm_hstate.kvm_vcpu = vcpu;
        tpaca->kvm_hstate.kvm_vcore = vc;
        tpaca->kvm_hstate.napping = 0;
        vcpu->cpu = vc->pcpu;
        smp_wmb();
#ifdef CONFIG_PPC_ICP_NATIVE
        if (vcpu->arch.ptid) {
                tpaca->cpu_start = 0x80;
                wmb();
                xics_wake_cpu(cpu);
                ++vc->n_woken;
        }
#endif
}

static void kvmppc_wait_for_nap(struct kvmppc_vcore *vc)
{
        int i;

        HMT_low();
        i = 0;
        while (vc->nap_count < vc->n_woken) {
                if (++i >= 1000000) {
                        pr_err("kvmppc_wait_for_nap timeout %d %d\n",
                               vc->nap_count, vc->n_woken);
                        break;
                }
                cpu_relax();
        }
        HMT_medium();
}

/*
 * Check that we are on thread 0 and that any other threads in
 * this core are off-line.
 */
static int on_primary_thread(void)
{
        int cpu = smp_processor_id();
        int thr = cpu_thread_in_core(cpu);

        if (thr)
                return 0;
        while (++thr < threads_per_core)
                if (cpu_online(cpu + thr))
                        return 0;
        return 1;
}

/*
 * Run a set of guest threads on a physical core.
 * Called with vc->lock held.
 */
static int kvmppc_run_core(struct kvmppc_vcore *vc)
{
        struct kvm_vcpu *vcpu, *vcpu0, *vnext;
        long ret;
        u64 now;
        int ptid;

        /* don't start if any threads have a signal pending */
        list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list)
                if (signal_pending(vcpu->arch.run_task))
                        return 0;

        /*
         * Make sure we are running on thread 0, and that
         * secondary threads are offline.
         * XXX we should also block attempts to bring any
         * secondary threads online.
         */
        if (threads_per_core > 1 && !on_primary_thread()) {
                list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list)
                        vcpu->arch.ret = -EBUSY;
                goto out;
        }

        /*
         * Assign physical thread IDs, first to non-ceded vcpus
         * and then to ceded ones.
         */
        ptid = 0;
        vcpu0 = NULL;
        list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list) {
                if (!vcpu->arch.ceded) {
                        if (!ptid)
                                vcpu0 = vcpu;
                        vcpu->arch.ptid = ptid++;
                }
        }
        if (!vcpu0)
                return 0;               /* nothing to run */
        list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list)
                if (vcpu->arch.ceded)
                        vcpu->arch.ptid = ptid++;

        vc->n_woken = 0;
        vc->nap_count = 0;
        vc->entry_exit_count = 0;
        vc->vcore_state = VCORE_RUNNING;
        vc->in_guest = 0;
        vc->pcpu = smp_processor_id();
        vc->napping_threads = 0;
        list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list)
                kvmppc_start_thread(vcpu);

        preempt_disable();
        spin_unlock(&vc->lock);

        kvm_guest_enter();
        __kvmppc_vcore_entry(NULL, vcpu0);

        spin_lock(&vc->lock);
        /* disable sending of IPIs on virtual external irqs */
        list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list)
                vcpu->cpu = -1;
        /* wait for secondary threads to finish writing their state to memory */
        if (vc->nap_count < vc->n_woken)
                kvmppc_wait_for_nap(vc);
        /* prevent other vcpu threads from doing kvmppc_start_thread() now */
        vc->vcore_state = VCORE_EXITING;
        spin_unlock(&vc->lock);

        /* make sure updates to secondary vcpu structs are visible now */
        smp_mb();
        kvm_guest_exit();

        preempt_enable();
        kvm_resched(vcpu);

        now = get_tb();
        list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list) {
                /* cancel pending dec exception if dec is positive */
                if (now < vcpu->arch.dec_expires &&
                    kvmppc_core_pending_dec(vcpu))
                        kvmppc_core_dequeue_dec(vcpu);

                ret = RESUME_GUEST;
                if (vcpu->arch.trap)
                        ret = kvmppc_handle_exit(vcpu->arch.kvm_run, vcpu,
                                                 vcpu->arch.run_task);

                vcpu->arch.ret = ret;
                vcpu->arch.trap = 0;

                if (vcpu->arch.ceded) {
                        if (ret != RESUME_GUEST)
                                kvmppc_end_cede(vcpu);
                        else
                                kvmppc_set_timer(vcpu);
                }
        }

        spin_lock(&vc->lock);
 out:
        vc->vcore_state = VCORE_INACTIVE;
        list_for_each_entry_safe(vcpu, vnext, &vc->runnable_threads,
                                 arch.run_list) {
                if (vcpu->arch.ret != RESUME_GUEST) {
                        kvmppc_remove_runnable(vc, vcpu);
                        wake_up(&vcpu->arch.cpu_run);
                }
        }

        return 1;
}

/*
 * Wait for some other vcpu thread to execute us, and
 * wake us up when we need to handle something in the host.
 */
static void kvmppc_wait_for_exec(struct kvm_vcpu *vcpu, int wait_state)
{
        DEFINE_WAIT(wait);

        prepare_to_wait(&vcpu->arch.cpu_run, &wait, wait_state);
        if (vcpu->arch.state == KVMPPC_VCPU_RUNNABLE)
                schedule();
        finish_wait(&vcpu->arch.cpu_run, &wait);
}

/*
 * All the vcpus in this vcore are idle, so wait for a decrementer
 * or external interrupt to one of the vcpus.  vc->lock is held.
 */
static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc)
{
        DEFINE_WAIT(wait);
        struct kvm_vcpu *v;
        int all_idle = 1;

        prepare_to_wait(&vc->wq, &wait, TASK_INTERRUPTIBLE);
        vc->vcore_state = VCORE_SLEEPING;
        spin_unlock(&vc->lock);
        list_for_each_entry(v, &vc->runnable_threads, arch.run_list) {
                if (!v->arch.ceded || v->arch.pending_exceptions) {
                        all_idle = 0;
                        break;
                }
        }
        if (all_idle)
                schedule();
        finish_wait(&vc->wq, &wait);
        spin_lock(&vc->lock);
        vc->vcore_state = VCORE_INACTIVE;
}

static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
{
        int n_ceded;
        int prev_state;
        struct kvmppc_vcore *vc;
        struct kvm_vcpu *v, *vn;

        kvm_run->exit_reason = 0;
        vcpu->arch.ret = RESUME_GUEST;
        vcpu->arch.trap = 0;

        /*
         * Synchronize with other threads in this virtual core
         */
        vc = vcpu->arch.vcore;
        spin_lock(&vc->lock);
        vcpu->arch.ceded = 0;
        vcpu->arch.run_task = current;
        vcpu->arch.kvm_run = kvm_run;
        prev_state = vcpu->arch.state;
        vcpu->arch.state = KVMPPC_VCPU_RUNNABLE;
        list_add_tail(&vcpu->arch.run_list, &vc->runnable_threads);
        ++vc->n_runnable;

        /*
         * This happens the first time this is called for a vcpu.
         * If the vcore is already running, we may be able to start
         * this thread straight away and have it join in.
         */
        if (prev_state == KVMPPC_VCPU_STOPPED) {
                if (vc->vcore_state == VCORE_RUNNING &&
                    VCORE_EXIT_COUNT(vc) == 0) {
                        vcpu->arch.ptid = vc->n_runnable - 1;
                        kvmppc_start_thread(vcpu);
                }

        } else if (prev_state == KVMPPC_VCPU_BUSY_IN_HOST)
                --vc->n_busy;

        while (vcpu->arch.state == KVMPPC_VCPU_RUNNABLE &&
               !signal_pending(current)) {
                if (vc->n_busy || vc->vcore_state != VCORE_INACTIVE) {
                        spin_unlock(&vc->lock);
                        kvmppc_wait_for_exec(vcpu, TASK_INTERRUPTIBLE);
                        spin_lock(&vc->lock);
                        continue;
                }
                n_ceded = 0;
                list_for_each_entry(v, &vc->runnable_threads, arch.run_list)
                        n_ceded += v->arch.ceded;
                if (n_ceded == vc->n_runnable)
                        kvmppc_vcore_blocked(vc);
                else
                        kvmppc_run_core(vc);

                list_for_each_entry_safe(v, vn, &vc->runnable_threads,
                                         arch.run_list) {
                        kvmppc_core_deliver_interrupts(v);
                        if (signal_pending(v->arch.run_task)) {
                                kvmppc_remove_runnable(vc, v);
                                v->stat.signal_exits++;
                                v->arch.kvm_run->exit_reason = KVM_EXIT_INTR;
                                v->arch.ret = -EINTR;
                                wake_up(&v->arch.cpu_run);
                        }
                }
        }

        if (signal_pending(current)) {
                if (vc->vcore_state == VCORE_RUNNING ||
                    vc->vcore_state == VCORE_EXITING) {
                        spin_unlock(&vc->lock);
                        kvmppc_wait_for_exec(vcpu, TASK_UNINTERRUPTIBLE);
                        spin_lock(&vc->lock);
                }
                if (vcpu->arch.state == KVMPPC_VCPU_RUNNABLE) {
                        kvmppc_remove_runnable(vc, vcpu);
                        vcpu->stat.signal_exits++;
                        kvm_run->exit_reason = KVM_EXIT_INTR;
                        vcpu->arch.ret = -EINTR;
                }
        }

        spin_unlock(&vc->lock);
        return vcpu->arch.ret;
}

int kvmppc_vcpu_run(struct kvm_run *run, struct kvm_vcpu *vcpu)
{
        int r;

        if (!vcpu->arch.sane) {
                run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
                return -EINVAL;
        }

        /* No need to go into the guest when all we'll do is come back out */
        if (signal_pending(current)) {
                run->exit_reason = KVM_EXIT_INTR;
                return -EINTR;
        }

        /* On PPC970, check that we have an RMA region */
        if (!vcpu->kvm->arch.rma && cpu_has_feature(CPU_FTR_ARCH_201))
                return -EPERM;

        flush_fp_to_thread(current);
        flush_altivec_to_thread(current);
        flush_vsx_to_thread(current);
        vcpu->arch.wqp = &vcpu->arch.vcore->wq;

        do {
                r = kvmppc_run_vcpu(run, vcpu);

                if (run->exit_reason == KVM_EXIT_PAPR_HCALL &&
                    !(vcpu->arch.shregs.msr & MSR_PR)) {
                        r = kvmppc_pseries_do_hcall(vcpu);
                        kvmppc_core_deliver_interrupts(vcpu);
                }
        } while (r == RESUME_GUEST);
        return r;
}

static long kvmppc_stt_npages(unsigned long window_size)
{
        return ALIGN((window_size >> SPAPR_TCE_SHIFT)
                     * sizeof(u64), PAGE_SIZE) / PAGE_SIZE;
}

static void release_spapr_tce_table(struct kvmppc_spapr_tce_table *stt)
{
        struct kvm *kvm = stt->kvm;
        int i;

        mutex_lock(&kvm->lock);
        list_del(&stt->list);
        for (i = 0; i < kvmppc_stt_npages(stt->window_size); i++)
                __free_page(stt->pages[i]);
        kfree(stt);
        mutex_unlock(&kvm->lock);

        kvm_put_kvm(kvm);
}

static int kvm_spapr_tce_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
        struct kvmppc_spapr_tce_table *stt = vma->vm_file->private_data;
        struct page *page;

        if (vmf->pgoff >= kvmppc_stt_npages(stt->window_size))
                return VM_FAULT_SIGBUS;

        page = stt->pages[vmf->pgoff];
        get_page(page);
        vmf->page = page;
        return 0;
}

static const struct vm_operations_struct kvm_spapr_tce_vm_ops = {
        .fault = kvm_spapr_tce_fault,
};

static int kvm_spapr_tce_mmap(struct file *file, struct vm_area_struct *vma)
{
        vma->vm_ops = &kvm_spapr_tce_vm_ops;
        return 0;
}

static int kvm_spapr_tce_release(struct inode *inode, struct file *filp)
{
        struct kvmppc_spapr_tce_table *stt = filp->private_data;

        release_spapr_tce_table(stt);
        return 0;
}

static struct file_operations kvm_spapr_tce_fops = {
        .mmap           = kvm_spapr_tce_mmap,
        .release        = kvm_spapr_tce_release,
};

long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
                                   struct kvm_create_spapr_tce *args)
{
        struct kvmppc_spapr_tce_table *stt = NULL;
        long npages;
        int ret = -ENOMEM;
        int i;

        /* Check this LIOBN hasn't been previously allocated */
        list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) {
                if (stt->liobn == args->liobn)
                        return -EBUSY;
        }

        npages = kvmppc_stt_npages(args->window_size);

        stt = kzalloc(sizeof(*stt) + npages* sizeof(struct page *),
                      GFP_KERNEL);
        if (!stt)
                goto fail;

        stt->liobn = args->liobn;
        stt->window_size = args->window_size;
        stt->kvm = kvm;

        for (i = 0; i < npages; i++) {
                stt->pages[i] = alloc_page(GFP_KERNEL | __GFP_ZERO);
                if (!stt->pages[i])
                        goto fail;
        }

        kvm_get_kvm(kvm);

        mutex_lock(&kvm->lock);
        list_add(&stt->list, &kvm->arch.spapr_tce_tables);

        mutex_unlock(&kvm->lock);

        return anon_inode_getfd("kvm-spapr-tce", &kvm_spapr_tce_fops,
                                stt, O_RDWR);

fail:
        if (stt) {
                for (i = 0; i < npages; i++)
                        if (stt->pages[i])
                                __free_page(stt->pages[i]);

                kfree(stt);
        }
        return ret;
}

/* Work out RMLS (real mode limit selector) field value for a given RMA size.
   Assumes POWER7 or PPC970. */
static inline int lpcr_rmls(unsigned long rma_size)
{
        switch (rma_size) {
        case 32ul << 20:        /* 32 MB */
                if (cpu_has_feature(CPU_FTR_ARCH_206))
                        return 8;       /* only supported on POWER7 */
                return -1;
        case 64ul << 20:        /* 64 MB */
                return 3;
        case 128ul << 20:       /* 128 MB */
                return 7;
        case 256ul << 20:       /* 256 MB */
                return 4;
        case 1ul << 30:         /* 1 GB */
                return 2;
        case 16ul << 30:        /* 16 GB */
                return 1;
        case 256ul << 30:       /* 256 GB */
                return 0;
        default:
                return -1;
        }
}

static int kvm_rma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
        struct kvmppc_rma_info *ri = vma->vm_file->private_data;
        struct page *page;

        if (vmf->pgoff >= ri->npages)
                return VM_FAULT_SIGBUS;

        page = pfn_to_page(ri->base_pfn + vmf->pgoff);
        get_page(page);
        vmf->page = page;
        return 0;
}

static const struct vm_operations_struct kvm_rma_vm_ops = {
        .fault = kvm_rma_fault,
};

static int kvm_rma_mmap(struct file *file, struct vm_area_struct *vma)
{
        vma->vm_flags |= VM_RESERVED;
        vma->vm_ops = &kvm_rma_vm_ops;
        return 0;
}

static int kvm_rma_release(struct inode *inode, struct file *filp)
{
        struct kvmppc_rma_info *ri = filp->private_data;

        kvm_release_rma(ri);
        return 0;
}

static struct file_operations kvm_rma_fops = {
        .mmap           = kvm_rma_mmap,
        .release        = kvm_rma_release,
};

long kvm_vm_ioctl_allocate_rma(struct kvm *kvm, struct kvm_allocate_rma *ret)
{
        struct kvmppc_rma_info *ri;
        long fd;

        ri = kvm_alloc_rma();
        if (!ri)
                return -ENOMEM;

        fd = anon_inode_getfd("kvm-rma", &kvm_rma_fops, ri, O_RDWR);
        if (fd < 0)
                kvm_release_rma(ri);

        ret->rma_size = ri->npages << PAGE_SHIFT;
        return fd;
}

static struct page *hva_to_page(unsigned long addr)
{
        struct page *page[1];
        int npages;

        might_sleep();

        npages = get_user_pages_fast(addr, 1, 1, page);

        if (unlikely(npages != 1))
                return 0;

        return page[0];
}

int kvmppc_core_prepare_memory_region(struct kvm *kvm,
                                struct kvm_userspace_memory_region *mem)
{
        unsigned long psize, porder;
        unsigned long i, npages, totalpages;
        unsigned long pg_ix;
        struct kvmppc_pginfo *pginfo;
        unsigned long hva;
        struct kvmppc_rma_info *ri = NULL;
        struct page *page;

        /* For now, only allow 16MB pages */
        porder = LARGE_PAGE_ORDER;
        psize = 1ul << porder;
        if ((mem->memory_size & (psize - 1)) ||
            (mem->guest_phys_addr & (psize - 1))) {
                pr_err("bad memory_size=%llx @ %llx\n",
                       mem->memory_size, mem->guest_phys_addr);
                return -EINVAL;
        }

        npages = mem->memory_size >> porder;
        totalpages = (mem->guest_phys_addr + mem->memory_size) >> porder;

        /* More memory than we have space to track? */
        if (totalpages > (1ul << (MAX_MEM_ORDER - LARGE_PAGE_ORDER)))
                return -EINVAL;

        /* Do we already have an RMA registered? */
        if (mem->guest_phys_addr == 0 && kvm->arch.rma)
                return -EINVAL;

        if (totalpages > kvm->arch.ram_npages)
                kvm->arch.ram_npages = totalpages;

        /* Is this one of our preallocated RMAs? */
        if (mem->guest_phys_addr == 0) {
                struct vm_area_struct *vma;

                down_read(&current->mm->mmap_sem);
                vma = find_vma(current->mm, mem->userspace_addr);
                if (vma && vma->vm_file &&
                    vma->vm_file->f_op == &kvm_rma_fops &&
                    mem->userspace_addr == vma->vm_start)
                        ri = vma->vm_file->private_data;
                up_read(&current->mm->mmap_sem);
                if (!ri && cpu_has_feature(CPU_FTR_ARCH_201)) {
                        pr_err("CPU requires an RMO\n");
                        return -EINVAL;
                }
        }

        if (ri) {
                unsigned long rma_size;
                unsigned long lpcr;
                long rmls;

                rma_size = ri->npages << PAGE_SHIFT;
                if (rma_size > mem->memory_size)
                        rma_size = mem->memory_size;
                rmls = lpcr_rmls(rma_size);
                if (rmls < 0) {
                        pr_err("Can't use RMA of 0x%lx bytes\n", rma_size);
                        return -EINVAL;
                }
                atomic_inc(&ri->use_count);
                kvm->arch.rma = ri;
                kvm->arch.n_rma_pages = rma_size >> porder;

                /* Update LPCR and RMOR */
                lpcr = kvm->arch.lpcr;
                if (cpu_has_feature(CPU_FTR_ARCH_201)) {
                        /* PPC970; insert RMLS value (split field) in HID4 */
                        lpcr &= ~((1ul << HID4_RMLS0_SH) |
                                  (3ul << HID4_RMLS2_SH));
                        lpcr |= ((rmls >> 2) << HID4_RMLS0_SH) |
                                ((rmls & 3) << HID4_RMLS2_SH);
                        /* RMOR is also in HID4 */
                        lpcr |= ((ri->base_pfn >> (26 - PAGE_SHIFT)) & 0xffff)
                                << HID4_RMOR_SH;
                } else {
                        /* POWER7 */
                        lpcr &= ~(LPCR_VPM0 | LPCR_VRMA_L);
                        lpcr |= rmls << LPCR_RMLS_SH;
                        kvm->arch.rmor = kvm->arch.rma->base_pfn << PAGE_SHIFT;
                }
                kvm->arch.lpcr = lpcr;
                pr_info("Using RMO at %lx size %lx (LPCR = %lx)\n",
                        ri->base_pfn << PAGE_SHIFT, rma_size, lpcr);
        }

        pg_ix = mem->guest_phys_addr >> porder;
        pginfo = kvm->arch.ram_pginfo + pg_ix;
        for (i = 0; i < npages; ++i, ++pg_ix) {
                if (ri && pg_ix < kvm->arch.n_rma_pages) {
                        pginfo[i].pfn = ri->base_pfn +
                                (pg_ix << (porder - PAGE_SHIFT));
                        continue;
                }
                hva = mem->userspace_addr + (i << porder);
                page = hva_to_page(hva);
                if (!page) {
                        pr_err("oops, no pfn for hva %lx\n", hva);
                        goto err;
                }
                /* Check it's a 16MB page */
                if (!PageHead(page) ||
                    compound_order(page) != (LARGE_PAGE_ORDER - PAGE_SHIFT)) {
                        pr_err("page at %lx isn't 16MB (o=%d)\n",
                               hva, compound_order(page));
                        goto err;
                }
                pginfo[i].pfn = page_to_pfn(page);
        }

        return 0;

 err:
        return -EINVAL;
}

void kvmppc_core_commit_memory_region(struct kvm *kvm,
                                struct kvm_userspace_memory_region *mem)
{
        if (mem->guest_phys_addr == 0 && mem->memory_size != 0 &&
            !kvm->arch.rma)
                kvmppc_map_vrma(kvm, mem);
}

int kvmppc_core_init_vm(struct kvm *kvm)
{
        long r;
        unsigned long npages = 1ul << (MAX_MEM_ORDER - LARGE_PAGE_ORDER);
        long err = -ENOMEM;
        unsigned long lpcr;

        /* Allocate hashed page table */
        r = kvmppc_alloc_hpt(kvm);
        if (r)
                return r;

        INIT_LIST_HEAD(&kvm->arch.spapr_tce_tables);

        kvm->arch.ram_pginfo = kzalloc(npages * sizeof(struct kvmppc_pginfo),
                                       GFP_KERNEL);
        if (!kvm->arch.ram_pginfo) {
                pr_err("kvmppc_core_init_vm: couldn't alloc %lu bytes\n",
                       npages * sizeof(struct kvmppc_pginfo));
                goto out_free;
        }

        kvm->arch.ram_npages = 0;
        kvm->arch.ram_psize = 1ul << LARGE_PAGE_ORDER;
        kvm->arch.ram_porder = LARGE_PAGE_ORDER;
        kvm->arch.rma = NULL;
        kvm->arch.n_rma_pages = 0;

        kvm->arch.host_sdr1 = mfspr(SPRN_SDR1);

        if (cpu_has_feature(CPU_FTR_ARCH_201)) {
                /* PPC970; HID4 is effectively the LPCR */
                unsigned long lpid = kvm->arch.lpid;
                kvm->arch.host_lpid = 0;
                kvm->arch.host_lpcr = lpcr = mfspr(SPRN_HID4);
                lpcr &= ~((3 << HID4_LPID1_SH) | (0xful << HID4_LPID5_SH));
                lpcr |= ((lpid >> 4) << HID4_LPID1_SH) |
                        ((lpid & 0xf) << HID4_LPID5_SH);
        } else {
                /* POWER7; init LPCR for virtual RMA mode */
                kvm->arch.host_lpid = mfspr(SPRN_LPID);
                kvm->arch.host_lpcr = lpcr = mfspr(SPRN_LPCR);
                lpcr &= LPCR_PECE | LPCR_LPES;
                lpcr |= (4UL << LPCR_DPFD_SH) | LPCR_HDICE |
                        LPCR_VPM0 | LPCR_VRMA_L;
        }
        kvm->arch.lpcr = lpcr;

        return 0;

 out_free:
        kvmppc_free_hpt(kvm);
        return err;
}

void kvmppc_core_destroy_vm(struct kvm *kvm)
{
        struct kvmppc_pginfo *pginfo;
        unsigned long i;

        if (kvm->arch.ram_pginfo) {
                pginfo = kvm->arch.ram_pginfo;
                kvm->arch.ram_pginfo = NULL;
                for (i = kvm->arch.n_rma_pages; i < kvm->arch.ram_npages; ++i)
                        if (pginfo[i].pfn)
                                put_page(pfn_to_page(pginfo[i].pfn));
                kfree(pginfo);
        }
        if (kvm->arch.rma) {
                kvm_release_rma(kvm->arch.rma);
                kvm->arch.rma = NULL;
        }

        kvmppc_free_hpt(kvm);
        WARN_ON(!list_empty(&kvm->arch.spapr_tce_tables));
}

/* These are stubs for now */
void kvmppc_mmu_pte_pflush(struct kvm_vcpu *vcpu, ulong pa_start, ulong pa_end)
{
}

/* We don't need to emulate any privileged instructions or dcbz */
int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu,
                           unsigned int inst, int *advance)
{
        return EMULATE_FAIL;
}

int kvmppc_core_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, int rs)
{
        return EMULATE_FAIL;
}

int kvmppc_core_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt)
{
        return EMULATE_FAIL;
}

static int kvmppc_book3s_hv_init(void)
{
        int r;

        r = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);

        if (r)
                return r;

        r = kvmppc_mmu_hv_init();

        return r;
}

static void kvmppc_book3s_hv_exit(void)
{
        kvm_exit();
}

module_init(kvmppc_book3s_hv_init);
module_exit(kvmppc_book3s_hv_exit);