korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-14 06:24:53 +08:00
Code Issues Packages Projects Releases Wiki Activity
371fefd6f2
linux/arch/powerpc/kvm/book3s_hv.c
Paul Mackerras 371fefd6f2 KVM: PPC: Allow book3s_hv guests to use SMT processor modes 
This lifts the restriction that book3s_hv guests can only run one
hardware thread per core, and allows them to use up to 4 threads
per core on POWER7.  The host still has to run single-threaded.

This capability is advertised to qemu through a new KVM_CAP_PPC_SMT
capability.  The return value of the ioctl querying this capability
is the number of vcpus per virtual CPU core (vcore), currently 4.

To use this, the host kernel should be booted with all threads
active, and then all the secondary threads should be offlined.
This will put the secondary threads into nap mode.  KVM will then
wake them from nap mode and use them for running guest code (while
they are still offline).  To wake the secondary threads, we send
them an IPI using a new xics_wake_cpu() function, implemented in
arch/powerpc/sysdev/xics/icp-native.c.  In other words, at this stage
we assume that the platform has a XICS interrupt controller and
we are using icp-native.c to drive it.  Since the woken thread will
need to acknowledge and clear the IPI, we also export the base
physical address of the XICS registers using kvmppc_set_xics_phys()
for use in the low-level KVM book3s code.

When a vcpu is created, it is assigned to a virtual CPU core.
The vcore number is obtained by dividing the vcpu number by the
number of threads per core in the host.  This number is exported
to userspace via the KVM_CAP_PPC_SMT capability.  If qemu wishes
to run the guest in single-threaded mode, it should make all vcpu
numbers be multiples of the number of threads per core.

We distinguish three states of a vcpu: runnable (i.e., ready to execute
the guest), blocked (that is, idle), and busy in host.  We currently
implement a policy that the vcore can run only when all its threads
are runnable or blocked.  This way, if a vcpu needs to execute elsewhere
in the kernel or in qemu, it can do so without being starved of CPU
by the other vcpus.

When a vcore starts to run, it executes in the context of one of the
vcpu threads.  The other vcpu threads all go to sleep and stay asleep
until something happens requiring the vcpu thread to return to qemu,
or to wake up to run the vcore (this can happen when another vcpu
thread goes from busy in host state to blocked).

It can happen that a vcpu goes from blocked to runnable state (e.g.
because of an interrupt), and the vcore it belongs to is already
running.  In that case it can start to run immediately as long as
the none of the vcpus in the vcore have started to exit the guest.
We send the next free thread in the vcore an IPI to get it to start
to execute the guest.  It synchronizes with the other threads via
the vcore->entry_exit_count field to make sure that it doesn't go
into the guest if the other vcpus are exiting by the time that it
is ready to actually enter the guest.

Note that there is no fixed relationship between the hardware thread
number and the vcpu number.  Hardware threads are assigned to vcpus
as they become runnable, so we will always use the lower-numbered
hardware threads in preference to higher-numbered threads if not all
the vcpus in the vcore are runnable, regardless of which vcpus are
runnable.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:57 +03:00

990 lines
24 KiB
C
Raw Blame History

/*
* 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/fs.h>
#include <linux/anon_inodes.h>
#include <linux/cpumask.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 <linux/gfp.h>
#include <linux/sched.h>
#include <linux/vmalloc.h>
#include <linux/highmem.h>
/* #define EXIT_DEBUG */
/* #define EXIT_DEBUG_SIMPLE */
/* #define EXIT_DEBUG_INT */
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)
{
}
static void kvmppc_vcpu_blocked(struct kvm_vcpu *vcpu);
static void kvmppc_vcpu_unblocked(struct kvm_vcpu *vcpu);
void kvmppc_vcpu_block(struct kvm_vcpu *vcpu)
{
u64 now;
unsigned long dec_nsec;
now = get_tb();
if (now >= vcpu->arch.dec_expires && !kvmppc_core_pending_dec(vcpu))
kvmppc_core_queue_dec(vcpu);
if (vcpu->arch.pending_exceptions)
return;
if (vcpu->arch.dec_expires != ~(u64)0) {
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);
}
kvmppc_vcpu_blocked(vcpu);
kvm_vcpu_block(vcpu);
vcpu->stat.halt_wakeup++;
if (vcpu->arch.dec_expires != ~(u64)0)
hrtimer_try_to_cancel(&vcpu->arch.dec_timer);
kvmppc_vcpu_unblocked(vcpu);
}
void kvmppc_set_msr(struct kvm_vcpu *vcpu, u64 msr)
{
vcpu->arch.shregs.msr = msr;
}
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->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:
vcpu->arch.shregs.msr |= MSR_EE;
vcpu->arch.ceded = 1;
smp_mb();
if (!vcpu->arch.prodded)
kvmppc_vcpu_block(vcpu);
else
vcpu->arch.prodded = 0;
smp_mb();
vcpu->arch.ceded = 0;
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;
}
if (!(r & RESUME_HOST)) {
/* To avoid clobbering exit_reason, only check for signals if
* we aren't already exiting to userspace for some other
* reason. */
if (signal_pending(tsk)) {
vcpu->stat.signal_exits++;
run->exit_reason = KVM_EXIT_INTR;
r = -EINTR;
} else {
kvmppc_core_deliver_interrupts(vcpu);
}
}
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_206))
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;
unsigned long lpcr;
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);
lpcr = kvm->arch.host_lpcr & (LPCR_PECE | LPCR_LPES);
lpcr |= LPCR_VPM0 | LPCR_VRMA_L | (4UL << LPCR_DPFD_SH) | LPCR_HDICE;
vcpu->arch.lpcr = lpcr;
kvmppc_mmu_book3s_hv_init(vcpu);
/*
* Some vcpus may start out in stopped state. If we initialize
* them to busy-in-host state they will stop other vcpus in the
* vcore from running. Instead we initialize them to blocked
* state, effectively considering them to be stopped until we
* see the first run ioctl for them.
*/
vcpu->arch.state = KVMPPC_VCPU_BLOCKED;
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);
}
kvm->arch.vcores[core] = vcore;
}
mutex_unlock(&kvm->lock);
if (!vcore)
goto free_vcpu;
spin_lock(&vcore->lock);
++vcore->num_threads;
++vcore->n_blocked;
spin_unlock(&vcore->lock);
vcpu->arch.vcore = vcore;
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_vcpu_blocked(struct kvm_vcpu *vcpu)
{
struct kvmppc_vcore *vc = vcpu->arch.vcore;
spin_lock(&vc->lock);
vcpu->arch.state = KVMPPC_VCPU_BLOCKED;
++vc->n_blocked;
if (vc->n_runnable > 0 &&
vc->n_runnable + vc->n_blocked == vc->num_threads) {
vcpu = list_first_entry(&vc->runnable_threads, struct kvm_vcpu,
arch.run_list);
wake_up(&vcpu->arch.cpu_run);
}
spin_unlock(&vc->lock);
}
static void kvmppc_vcpu_unblocked(struct kvm_vcpu *vcpu)
{
struct kvmppc_vcore *vc = vcpu->arch.vcore;
spin_lock(&vc->lock);
vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST;
--vc->n_blocked;
spin_unlock(&vc->lock);
}
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;
/* 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;
cpu = vc->pcpu + vcpu->arch.ptid;
tpaca = &paca[cpu];
tpaca->kvm_hstate.kvm_vcpu = vcpu;
tpaca->kvm_hstate.kvm_vcore = vc;
smp_wmb();
#ifdef CONFIG_PPC_ICP_NATIVE
if (vcpu->arch.ptid) {
tpaca->cpu_start = 0x80;
tpaca->kvm_hstate.in_guest = KVM_GUEST_MODE_GUEST;
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, *vnext;
long ret;
u64 now;
/* 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;
}
vc->n_woken = 0;
vc->nap_count = 0;
vc->entry_exit_count = 0;
vc->vcore_running = 1;
vc->in_guest = 0;
vc->pcpu = smp_processor_id();
list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list)
kvmppc_start_thread(vcpu);
vcpu = list_first_entry(&vc->runnable_threads, struct kvm_vcpu,
arch.run_list);
spin_unlock(&vc->lock);
preempt_disable();
kvm_guest_enter();
__kvmppc_vcore_entry(NULL, vcpu);
/* wait for secondary threads to finish writing their state to memory */
spin_lock(&vc->lock);
if (vc->nap_count < vc->n_woken)
kvmppc_wait_for_nap(vc);
/* prevent other vcpu threads from doing kvmppc_start_thread() now */
vc->vcore_running = 2;
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);
if (!vcpu->arch.trap) {
if (signal_pending(vcpu->arch.run_task)) {
vcpu->arch.kvm_run->exit_reason = KVM_EXIT_INTR;
vcpu->arch.ret = -EINTR;
}
continue; /* didn't get to run */
}
ret = kvmppc_handle_exit(vcpu->arch.kvm_run, vcpu,
vcpu->arch.run_task);
vcpu->arch.ret = ret;
vcpu->arch.trap = 0;
}
spin_lock(&vc->lock);
out:
vc->vcore_running = 0;
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;
}
static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
{
int ptid;
int wait_state;
struct kvmppc_vcore *vc;
DEFINE_WAIT(wait);
/* No need to go into the guest when all we do is going out */
if (signal_pending(current)) {
kvm_run->exit_reason = KVM_EXIT_INTR;
return -EINTR;
}
kvm_run->exit_reason = 0;
vcpu->arch.ret = RESUME_GUEST;
vcpu->arch.trap = 0;
flush_fp_to_thread(current);
flush_altivec_to_thread(current);
flush_vsx_to_thread(current);
/*
* Synchronize with other threads in this virtual core
*/
vc = vcpu->arch.vcore;
spin_lock(&vc->lock);
/* This happens the first time this is called for a vcpu */
if (vcpu->arch.state == KVMPPC_VCPU_BLOCKED)
--vc->n_blocked;
vcpu->arch.state = KVMPPC_VCPU_RUNNABLE;
ptid = vc->n_runnable;
vcpu->arch.run_task = current;
vcpu->arch.kvm_run = kvm_run;
vcpu->arch.ptid = ptid;
list_add_tail(&vcpu->arch.run_list, &vc->runnable_threads);
++vc->n_runnable;
wait_state = TASK_INTERRUPTIBLE;
while (vcpu->arch.state == KVMPPC_VCPU_RUNNABLE) {
if (signal_pending(current)) {
if (!vc->vcore_running) {
kvm_run->exit_reason = KVM_EXIT_INTR;
vcpu->arch.ret = -EINTR;
break;
}
/* have to wait for vcore to stop executing guest */
wait_state = TASK_UNINTERRUPTIBLE;
smp_send_reschedule(vc->pcpu);
}
if (!vc->vcore_running &&
vc->n_runnable + vc->n_blocked == vc->num_threads) {
/* we can run now */
if (kvmppc_run_core(vc))
continue;
}
if (vc->vcore_running == 1 && VCORE_EXIT_COUNT(vc) == 0)
kvmppc_start_thread(vcpu);
/* wait for other threads to come in, or wait for vcore */
prepare_to_wait(&vcpu->arch.cpu_run, &wait, wait_state);
spin_unlock(&vc->lock);
schedule();
finish_wait(&vcpu->arch.cpu_run, &wait);
spin_lock(&vc->lock);
}
if (vcpu->arch.state == KVMPPC_VCPU_RUNNABLE)
kvmppc_remove_runnable(vc, vcpu);
spin_unlock(&vc->lock);
return vcpu->arch.ret;
}
int kvmppc_vcpu_run(struct kvm_run *run, struct kvm_vcpu *vcpu)
{
int r;
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;
}
int kvmppc_core_prepare_memory_region(struct kvm *kvm,
struct kvm_userspace_memory_region *mem)
{
if (mem->guest_phys_addr == 0 && mem->memory_size != 0)
return kvmppc_prepare_vrma(kvm, mem);
return 0;
}
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)
kvmppc_map_vrma(kvm, mem);
}
int kvmppc_core_init_vm(struct kvm *kvm)
{
long r;
/* Allocate hashed page table */
r = kvmppc_alloc_hpt(kvm);
if (r)
return r;
INIT_LIST_HEAD(&kvm->arch.spapr_tce_tables);
return 0;
}
void kvmppc_core_destroy_vm(struct kvm *kvm)
{
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);
Reference in New Issue View Git Blame Copy Permalink