linux_dsm_epyc7002/arch/powerpc/kvm/book3s_hv_builtin.c
Paul Mackerras 03f953329b KVM: PPC: Book3S: Allow XICS emulation to work in nested hosts using XIVE
Currently, the KVM code assumes that if the host kernel is using the
XIVE interrupt controller (the new interrupt controller that first
appeared in POWER9 systems), then the in-kernel XICS emulation will
use the XIVE hardware to deliver interrupts to the guest.  However,
this only works when the host is running in hypervisor mode and has
full access to all of the XIVE functionality.  It doesn't work in any
nested virtualization scenario, either with PR KVM or nested-HV KVM,
because the XICS-on-XIVE code calls directly into the native-XIVE
routines, which are not initialized and cannot function correctly
because they use OPAL calls, and OPAL is not available in a guest.

This means that using the in-kernel XICS emulation in a nested
hypervisor that is using XIVE as its interrupt controller will cause a
(nested) host kernel crash.  To fix this, we change most of the places
where the current code calls xive_enabled() to select between the
XICS-on-XIVE emulation and the plain XICS emulation to call a new
function, xics_on_xive(), which returns false in a guest.

However, there is a further twist.  The plain XICS emulation has some
functions which are used in real mode and access the underlying XICS
controller (the interrupt controller of the host) directly.  In the
case of a nested hypervisor, this means doing XICS hypercalls
directly.  When the nested host is using XIVE as its interrupt
controller, these hypercalls will fail.  Therefore this also adds
checks in the places where the XICS emulation wants to access the
underlying interrupt controller directly, and if that is XIVE, makes
the code use the virtual mode fallback paths, which call generic
kernel infrastructure rather than doing direct XICS access.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-19 16:00:15 +11:00

808 lines
20 KiB
C

/*
* Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
*
* 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/cpu.h>
#include <linux/kvm_host.h>
#include <linux/preempt.h>
#include <linux/export.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/init.h>
#include <linux/memblock.h>
#include <linux/sizes.h>
#include <linux/cma.h>
#include <linux/bitops.h>
#include <asm/asm-prototypes.h>
#include <asm/cputable.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
#include <asm/archrandom.h>
#include <asm/xics.h>
#include <asm/xive.h>
#include <asm/dbell.h>
#include <asm/cputhreads.h>
#include <asm/io.h>
#include <asm/opal.h>
#include <asm/smp.h>
#define KVM_CMA_CHUNK_ORDER 18
#include "book3s_xics.h"
#include "book3s_xive.h"
/*
* The XIVE module will populate these when it loads
*/
unsigned long (*__xive_vm_h_xirr)(struct kvm_vcpu *vcpu);
unsigned long (*__xive_vm_h_ipoll)(struct kvm_vcpu *vcpu, unsigned long server);
int (*__xive_vm_h_ipi)(struct kvm_vcpu *vcpu, unsigned long server,
unsigned long mfrr);
int (*__xive_vm_h_cppr)(struct kvm_vcpu *vcpu, unsigned long cppr);
int (*__xive_vm_h_eoi)(struct kvm_vcpu *vcpu, unsigned long xirr);
EXPORT_SYMBOL_GPL(__xive_vm_h_xirr);
EXPORT_SYMBOL_GPL(__xive_vm_h_ipoll);
EXPORT_SYMBOL_GPL(__xive_vm_h_ipi);
EXPORT_SYMBOL_GPL(__xive_vm_h_cppr);
EXPORT_SYMBOL_GPL(__xive_vm_h_eoi);
/*
* Hash page table alignment on newer cpus(CPU_FTR_ARCH_206)
* should be power of 2.
*/
#define HPT_ALIGN_PAGES ((1 << 18) >> PAGE_SHIFT) /* 256k */
/*
* By default we reserve 5% of memory for hash pagetable allocation.
*/
static unsigned long kvm_cma_resv_ratio = 5;
static struct cma *kvm_cma;
static int __init early_parse_kvm_cma_resv(char *p)
{
pr_debug("%s(%s)\n", __func__, p);
if (!p)
return -EINVAL;
return kstrtoul(p, 0, &kvm_cma_resv_ratio);
}
early_param("kvm_cma_resv_ratio", early_parse_kvm_cma_resv);
struct page *kvm_alloc_hpt_cma(unsigned long nr_pages)
{
VM_BUG_ON(order_base_2(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT);
return cma_alloc(kvm_cma, nr_pages, order_base_2(HPT_ALIGN_PAGES),
false);
}
EXPORT_SYMBOL_GPL(kvm_alloc_hpt_cma);
void kvm_free_hpt_cma(struct page *page, unsigned long nr_pages)
{
cma_release(kvm_cma, page, nr_pages);
}
EXPORT_SYMBOL_GPL(kvm_free_hpt_cma);
/**
* kvm_cma_reserve() - reserve area for kvm hash pagetable
*
* This function reserves memory from early allocator. It should be
* called by arch specific code once the memblock allocator
* has been activated and all other subsystems have already allocated/reserved
* memory.
*/
void __init kvm_cma_reserve(void)
{
unsigned long align_size;
struct memblock_region *reg;
phys_addr_t selected_size = 0;
/*
* We need CMA reservation only when we are in HV mode
*/
if (!cpu_has_feature(CPU_FTR_HVMODE))
return;
/*
* We cannot use memblock_phys_mem_size() here, because
* memblock_analyze() has not been called yet.
*/
for_each_memblock(memory, reg)
selected_size += memblock_region_memory_end_pfn(reg) -
memblock_region_memory_base_pfn(reg);
selected_size = (selected_size * kvm_cma_resv_ratio / 100) << PAGE_SHIFT;
if (selected_size) {
pr_debug("%s: reserving %ld MiB for global area\n", __func__,
(unsigned long)selected_size / SZ_1M);
align_size = HPT_ALIGN_PAGES << PAGE_SHIFT;
cma_declare_contiguous(0, selected_size, 0, align_size,
KVM_CMA_CHUNK_ORDER - PAGE_SHIFT, false, "kvm_cma",
&kvm_cma);
}
}
/*
* Real-mode H_CONFER implementation.
* We check if we are the only vcpu out of this virtual core
* still running in the guest and not ceded. If so, we pop up
* to the virtual-mode implementation; if not, just return to
* the guest.
*/
long int kvmppc_rm_h_confer(struct kvm_vcpu *vcpu, int target,
unsigned int yield_count)
{
struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore;
int ptid = local_paca->kvm_hstate.ptid;
int threads_running;
int threads_ceded;
int threads_conferring;
u64 stop = get_tb() + 10 * tb_ticks_per_usec;
int rv = H_SUCCESS; /* => don't yield */
set_bit(ptid, &vc->conferring_threads);
while ((get_tb() < stop) && !VCORE_IS_EXITING(vc)) {
threads_running = VCORE_ENTRY_MAP(vc);
threads_ceded = vc->napping_threads;
threads_conferring = vc->conferring_threads;
if ((threads_ceded | threads_conferring) == threads_running) {
rv = H_TOO_HARD; /* => do yield */
break;
}
}
clear_bit(ptid, &vc->conferring_threads);
return rv;
}
/*
* When running HV mode KVM we need to block certain operations while KVM VMs
* exist in the system. We use a counter of VMs to track this.
*
* One of the operations we need to block is onlining of secondaries, so we
* protect hv_vm_count with get/put_online_cpus().
*/
static atomic_t hv_vm_count;
void kvm_hv_vm_activated(void)
{
get_online_cpus();
atomic_inc(&hv_vm_count);
put_online_cpus();
}
EXPORT_SYMBOL_GPL(kvm_hv_vm_activated);
void kvm_hv_vm_deactivated(void)
{
get_online_cpus();
atomic_dec(&hv_vm_count);
put_online_cpus();
}
EXPORT_SYMBOL_GPL(kvm_hv_vm_deactivated);
bool kvm_hv_mode_active(void)
{
return atomic_read(&hv_vm_count) != 0;
}
extern int hcall_real_table[], hcall_real_table_end[];
int kvmppc_hcall_impl_hv_realmode(unsigned long cmd)
{
cmd /= 4;
if (cmd < hcall_real_table_end - hcall_real_table &&
hcall_real_table[cmd])
return 1;
return 0;
}
EXPORT_SYMBOL_GPL(kvmppc_hcall_impl_hv_realmode);
int kvmppc_hwrng_present(void)
{
return powernv_hwrng_present();
}
EXPORT_SYMBOL_GPL(kvmppc_hwrng_present);
long kvmppc_h_random(struct kvm_vcpu *vcpu)
{
int r;
/* Only need to do the expensive mfmsr() on radix */
if (kvm_is_radix(vcpu->kvm) && (mfmsr() & MSR_IR))
r = powernv_get_random_long(&vcpu->arch.regs.gpr[4]);
else
r = powernv_get_random_real_mode(&vcpu->arch.regs.gpr[4]);
if (r)
return H_SUCCESS;
return H_HARDWARE;
}
/*
* Send an interrupt or message to another CPU.
* The caller needs to include any barrier needed to order writes
* to memory vs. the IPI/message.
*/
void kvmhv_rm_send_ipi(int cpu)
{
void __iomem *xics_phys;
unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER);
/* For a nested hypervisor, use the XICS via hcall */
if (kvmhv_on_pseries()) {
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
plpar_hcall_raw(H_IPI, retbuf, get_hard_smp_processor_id(cpu),
IPI_PRIORITY);
return;
}
/* On POWER9 we can use msgsnd for any destination cpu. */
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
msg |= get_hard_smp_processor_id(cpu);
__asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg));
return;
}
/* On POWER8 for IPIs to threads in the same core, use msgsnd. */
if (cpu_has_feature(CPU_FTR_ARCH_207S) &&
cpu_first_thread_sibling(cpu) ==
cpu_first_thread_sibling(raw_smp_processor_id())) {
msg |= cpu_thread_in_core(cpu);
__asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg));
return;
}
/* We should never reach this */
if (WARN_ON_ONCE(xics_on_xive()))
return;
/* Else poke the target with an IPI */
xics_phys = paca_ptrs[cpu]->kvm_hstate.xics_phys;
if (xics_phys)
__raw_rm_writeb(IPI_PRIORITY, xics_phys + XICS_MFRR);
else
opal_int_set_mfrr(get_hard_smp_processor_id(cpu), IPI_PRIORITY);
}
/*
* The following functions are called from the assembly code
* in book3s_hv_rmhandlers.S.
*/
static void kvmhv_interrupt_vcore(struct kvmppc_vcore *vc, int active)
{
int cpu = vc->pcpu;
/* Order setting of exit map vs. msgsnd/IPI */
smp_mb();
for (; active; active >>= 1, ++cpu)
if (active & 1)
kvmhv_rm_send_ipi(cpu);
}
void kvmhv_commence_exit(int trap)
{
struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore;
int ptid = local_paca->kvm_hstate.ptid;
struct kvm_split_mode *sip = local_paca->kvm_hstate.kvm_split_mode;
int me, ee, i, t;
int cpu0;
/* Set our bit in the threads-exiting-guest map in the 0xff00
bits of vcore->entry_exit_map */
me = 0x100 << ptid;
do {
ee = vc->entry_exit_map;
} while (cmpxchg(&vc->entry_exit_map, ee, ee | me) != ee);
/* Are we the first here? */
if ((ee >> 8) != 0)
return;
/*
* Trigger the other threads in this vcore to exit the guest.
* If this is a hypervisor decrementer interrupt then they
* will be already on their way out of the guest.
*/
if (trap != BOOK3S_INTERRUPT_HV_DECREMENTER)
kvmhv_interrupt_vcore(vc, ee & ~(1 << ptid));
/*
* If we are doing dynamic micro-threading, interrupt the other
* subcores to pull them out of their guests too.
*/
if (!sip)
return;
for (i = 0; i < MAX_SUBCORES; ++i) {
vc = sip->vc[i];
if (!vc)
break;
do {
ee = vc->entry_exit_map;
/* Already asked to exit? */
if ((ee >> 8) != 0)
break;
} while (cmpxchg(&vc->entry_exit_map, ee,
ee | VCORE_EXIT_REQ) != ee);
if ((ee >> 8) == 0)
kvmhv_interrupt_vcore(vc, ee);
}
/*
* On POWER9 when running a HPT guest on a radix host (sip != NULL),
* we have to interrupt inactive CPU threads to get them to
* restore the host LPCR value.
*/
if (sip->lpcr_req) {
if (cmpxchg(&sip->do_restore, 0, 1) == 0) {
vc = local_paca->kvm_hstate.kvm_vcore;
cpu0 = vc->pcpu + ptid - local_paca->kvm_hstate.tid;
for (t = 1; t < threads_per_core; ++t) {
if (sip->napped[t])
kvmhv_rm_send_ipi(cpu0 + t);
}
}
}
}
struct kvmppc_host_rm_ops *kvmppc_host_rm_ops_hv;
EXPORT_SYMBOL_GPL(kvmppc_host_rm_ops_hv);
#ifdef CONFIG_KVM_XICS
static struct kvmppc_irq_map *get_irqmap(struct kvmppc_passthru_irqmap *pimap,
u32 xisr)
{
int i;
/*
* We access the mapped array here without a lock. That
* is safe because we never reduce the number of entries
* in the array and we never change the v_hwirq field of
* an entry once it is set.
*
* We have also carefully ordered the stores in the writer
* and the loads here in the reader, so that if we find a matching
* hwirq here, the associated GSI and irq_desc fields are valid.
*/
for (i = 0; i < pimap->n_mapped; i++) {
if (xisr == pimap->mapped[i].r_hwirq) {
/*
* Order subsequent reads in the caller to serialize
* with the writer.
*/
smp_rmb();
return &pimap->mapped[i];
}
}
return NULL;
}
/*
* If we have an interrupt that's not an IPI, check if we have a
* passthrough adapter and if so, check if this external interrupt
* is for the adapter.
* We will attempt to deliver the IRQ directly to the target VCPU's
* ICP, the virtual ICP (based on affinity - the xive value in ICS).
*
* If the delivery fails or if this is not for a passthrough adapter,
* return to the host to handle this interrupt. We earlier
* saved a copy of the XIRR in the PACA, it will be picked up by
* the host ICP driver.
*/
static int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again)
{
struct kvmppc_passthru_irqmap *pimap;
struct kvmppc_irq_map *irq_map;
struct kvm_vcpu *vcpu;
vcpu = local_paca->kvm_hstate.kvm_vcpu;
if (!vcpu)
return 1;
pimap = kvmppc_get_passthru_irqmap(vcpu->kvm);
if (!pimap)
return 1;
irq_map = get_irqmap(pimap, xisr);
if (!irq_map)
return 1;
/* We're handling this interrupt, generic code doesn't need to */
local_paca->kvm_hstate.saved_xirr = 0;
return kvmppc_deliver_irq_passthru(vcpu, xirr, irq_map, pimap, again);
}
#else
static inline int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again)
{
return 1;
}
#endif
/*
* Determine what sort of external interrupt is pending (if any).
* Returns:
* 0 if no interrupt is pending
* 1 if an interrupt is pending that needs to be handled by the host
* 2 Passthrough that needs completion in the host
* -1 if there was a guest wakeup IPI (which has now been cleared)
* -2 if there is PCI passthrough external interrupt that was handled
*/
static long kvmppc_read_one_intr(bool *again);
long kvmppc_read_intr(void)
{
long ret = 0;
long rc;
bool again;
if (xive_enabled())
return 1;
do {
again = false;
rc = kvmppc_read_one_intr(&again);
if (rc && (ret == 0 || rc > ret))
ret = rc;
} while (again);
return ret;
}
static long kvmppc_read_one_intr(bool *again)
{
void __iomem *xics_phys;
u32 h_xirr;
__be32 xirr;
u32 xisr;
u8 host_ipi;
int64_t rc;
if (xive_enabled())
return 1;
/* see if a host IPI is pending */
host_ipi = local_paca->kvm_hstate.host_ipi;
if (host_ipi)
return 1;
/* Now read the interrupt from the ICP */
if (kvmhv_on_pseries()) {
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
rc = plpar_hcall_raw(H_XIRR, retbuf, 0xFF);
xirr = cpu_to_be32(retbuf[0]);
} else {
xics_phys = local_paca->kvm_hstate.xics_phys;
rc = 0;
if (!xics_phys)
rc = opal_int_get_xirr(&xirr, false);
else
xirr = __raw_rm_readl(xics_phys + XICS_XIRR);
}
if (rc < 0)
return 1;
/*
* Save XIRR for later. Since we get control in reverse endian
* on LE systems, save it byte reversed and fetch it back in
* host endian. Note that xirr is the value read from the
* XIRR register, while h_xirr is the host endian version.
*/
h_xirr = be32_to_cpu(xirr);
local_paca->kvm_hstate.saved_xirr = h_xirr;
xisr = h_xirr & 0xffffff;
/*
* Ensure that the store/load complete to guarantee all side
* effects of loading from XIRR has completed
*/
smp_mb();
/* if nothing pending in the ICP */
if (!xisr)
return 0;
/* We found something in the ICP...
*
* If it is an IPI, clear the MFRR and EOI it.
*/
if (xisr == XICS_IPI) {
rc = 0;
if (kvmhv_on_pseries()) {
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
plpar_hcall_raw(H_IPI, retbuf,
hard_smp_processor_id(), 0xff);
plpar_hcall_raw(H_EOI, retbuf, h_xirr);
} else if (xics_phys) {
__raw_rm_writeb(0xff, xics_phys + XICS_MFRR);
__raw_rm_writel(xirr, xics_phys + XICS_XIRR);
} else {
opal_int_set_mfrr(hard_smp_processor_id(), 0xff);
rc = opal_int_eoi(h_xirr);
}
/* If rc > 0, there is another interrupt pending */
*again = rc > 0;
/*
* Need to ensure side effects of above stores
* complete before proceeding.
*/
smp_mb();
/*
* We need to re-check host IPI now in case it got set in the
* meantime. If it's clear, we bounce the interrupt to the
* guest
*/
host_ipi = local_paca->kvm_hstate.host_ipi;
if (unlikely(host_ipi != 0)) {
/* We raced with the host,
* we need to resend that IPI, bummer
*/
if (kvmhv_on_pseries()) {
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
plpar_hcall_raw(H_IPI, retbuf,
hard_smp_processor_id(),
IPI_PRIORITY);
} else if (xics_phys)
__raw_rm_writeb(IPI_PRIORITY,
xics_phys + XICS_MFRR);
else
opal_int_set_mfrr(hard_smp_processor_id(),
IPI_PRIORITY);
/* Let side effects complete */
smp_mb();
return 1;
}
/* OK, it's an IPI for us */
local_paca->kvm_hstate.saved_xirr = 0;
return -1;
}
return kvmppc_check_passthru(xisr, xirr, again);
}
#ifdef CONFIG_KVM_XICS
static inline bool is_rm(void)
{
return !(mfmsr() & MSR_DR);
}
unsigned long kvmppc_rm_h_xirr(struct kvm_vcpu *vcpu)
{
if (!kvmppc_xics_enabled(vcpu))
return H_TOO_HARD;
if (xics_on_xive()) {
if (is_rm())
return xive_rm_h_xirr(vcpu);
if (unlikely(!__xive_vm_h_xirr))
return H_NOT_AVAILABLE;
return __xive_vm_h_xirr(vcpu);
} else
return xics_rm_h_xirr(vcpu);
}
unsigned long kvmppc_rm_h_xirr_x(struct kvm_vcpu *vcpu)
{
if (!kvmppc_xics_enabled(vcpu))
return H_TOO_HARD;
vcpu->arch.regs.gpr[5] = get_tb();
if (xics_on_xive()) {
if (is_rm())
return xive_rm_h_xirr(vcpu);
if (unlikely(!__xive_vm_h_xirr))
return H_NOT_AVAILABLE;
return __xive_vm_h_xirr(vcpu);
} else
return xics_rm_h_xirr(vcpu);
}
unsigned long kvmppc_rm_h_ipoll(struct kvm_vcpu *vcpu, unsigned long server)
{
if (!kvmppc_xics_enabled(vcpu))
return H_TOO_HARD;
if (xics_on_xive()) {
if (is_rm())
return xive_rm_h_ipoll(vcpu, server);
if (unlikely(!__xive_vm_h_ipoll))
return H_NOT_AVAILABLE;
return __xive_vm_h_ipoll(vcpu, server);
} else
return H_TOO_HARD;
}
int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
unsigned long mfrr)
{
if (!kvmppc_xics_enabled(vcpu))
return H_TOO_HARD;
if (xics_on_xive()) {
if (is_rm())
return xive_rm_h_ipi(vcpu, server, mfrr);
if (unlikely(!__xive_vm_h_ipi))
return H_NOT_AVAILABLE;
return __xive_vm_h_ipi(vcpu, server, mfrr);
} else
return xics_rm_h_ipi(vcpu, server, mfrr);
}
int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr)
{
if (!kvmppc_xics_enabled(vcpu))
return H_TOO_HARD;
if (xics_on_xive()) {
if (is_rm())
return xive_rm_h_cppr(vcpu, cppr);
if (unlikely(!__xive_vm_h_cppr))
return H_NOT_AVAILABLE;
return __xive_vm_h_cppr(vcpu, cppr);
} else
return xics_rm_h_cppr(vcpu, cppr);
}
int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr)
{
if (!kvmppc_xics_enabled(vcpu))
return H_TOO_HARD;
if (xics_on_xive()) {
if (is_rm())
return xive_rm_h_eoi(vcpu, xirr);
if (unlikely(!__xive_vm_h_eoi))
return H_NOT_AVAILABLE;
return __xive_vm_h_eoi(vcpu, xirr);
} else
return xics_rm_h_eoi(vcpu, xirr);
}
#endif /* CONFIG_KVM_XICS */
void kvmppc_bad_interrupt(struct pt_regs *regs)
{
/*
* 100 could happen at any time, 200 can happen due to invalid real
* address access for example (or any time due to a hardware problem).
*/
if (TRAP(regs) == 0x100) {
get_paca()->in_nmi++;
system_reset_exception(regs);
get_paca()->in_nmi--;
} else if (TRAP(regs) == 0x200) {
machine_check_exception(regs);
} else {
die("Bad interrupt in KVM entry/exit code", regs, SIGABRT);
}
panic("Bad KVM trap");
}
/*
* Functions used to switch LPCR HR and UPRT bits on all threads
* when entering and exiting HPT guests on a radix host.
*/
#define PHASE_REALMODE 1 /* in real mode */
#define PHASE_SET_LPCR 2 /* have set LPCR */
#define PHASE_OUT_OF_GUEST 4 /* have finished executing in guest */
#define PHASE_RESET_LPCR 8 /* have reset LPCR to host value */
#define ALL(p) (((p) << 24) | ((p) << 16) | ((p) << 8) | (p))
static void wait_for_sync(struct kvm_split_mode *sip, int phase)
{
int thr = local_paca->kvm_hstate.tid;
sip->lpcr_sync.phase[thr] |= phase;
phase = ALL(phase);
while ((sip->lpcr_sync.allphases & phase) != phase) {
HMT_low();
barrier();
}
HMT_medium();
}
void kvmhv_p9_set_lpcr(struct kvm_split_mode *sip)
{
unsigned long rb, set;
/* wait for every other thread to get to real mode */
wait_for_sync(sip, PHASE_REALMODE);
/* Set LPCR and LPIDR */
mtspr(SPRN_LPCR, sip->lpcr_req);
mtspr(SPRN_LPID, sip->lpidr_req);
isync();
/* Invalidate the TLB on thread 0 */
if (local_paca->kvm_hstate.tid == 0) {
sip->do_set = 0;
asm volatile("ptesync" : : : "memory");
for (set = 0; set < POWER9_TLB_SETS_RADIX; ++set) {
rb = TLBIEL_INVAL_SET_LPID +
(set << TLBIEL_INVAL_SET_SHIFT);
asm volatile(PPC_TLBIEL(%0, %1, 0, 0, 0) : :
"r" (rb), "r" (0));
}
asm volatile("ptesync" : : : "memory");
}
/* indicate that we have done so and wait for others */
wait_for_sync(sip, PHASE_SET_LPCR);
/* order read of sip->lpcr_sync.allphases vs. sip->do_set */
smp_rmb();
}
/*
* Called when a thread that has been in the guest needs
* to reload the host LPCR value - but only on POWER9 when
* running a HPT guest on a radix host.
*/
void kvmhv_p9_restore_lpcr(struct kvm_split_mode *sip)
{
/* we're out of the guest... */
wait_for_sync(sip, PHASE_OUT_OF_GUEST);
mtspr(SPRN_LPID, 0);
mtspr(SPRN_LPCR, sip->host_lpcr);
isync();
if (local_paca->kvm_hstate.tid == 0) {
sip->do_restore = 0;
smp_wmb(); /* order store of do_restore vs. phase */
}
wait_for_sync(sip, PHASE_RESET_LPCR);
smp_mb();
local_paca->kvm_hstate.kvm_split_mode = NULL;
}
/*
* Is there a PRIV_DOORBELL pending for the guest (on POWER9)?
* Can we inject a Decrementer or a External interrupt?
*/
void kvmppc_guest_entry_inject_int(struct kvm_vcpu *vcpu)
{
int ext;
unsigned long vec = 0;
unsigned long lpcr;
/* Insert EXTERNAL bit into LPCR at the MER bit position */
ext = (vcpu->arch.pending_exceptions >> BOOK3S_IRQPRIO_EXTERNAL) & 1;
lpcr = mfspr(SPRN_LPCR);
lpcr |= ext << LPCR_MER_SH;
mtspr(SPRN_LPCR, lpcr);
isync();
if (vcpu->arch.shregs.msr & MSR_EE) {
if (ext) {
vec = BOOK3S_INTERRUPT_EXTERNAL;
} else {
long int dec = mfspr(SPRN_DEC);
if (!(lpcr & LPCR_LD))
dec = (int) dec;
if (dec < 0)
vec = BOOK3S_INTERRUPT_DECREMENTER;
}
}
if (vec) {
unsigned long msr, old_msr = vcpu->arch.shregs.msr;
kvmppc_set_srr0(vcpu, kvmppc_get_pc(vcpu));
kvmppc_set_srr1(vcpu, old_msr);
kvmppc_set_pc(vcpu, vec);
msr = vcpu->arch.intr_msr;
if (MSR_TM_ACTIVE(old_msr))
msr |= MSR_TS_S;
vcpu->arch.shregs.msr = msr;
}
if (vcpu->arch.doorbell_request) {
mtspr(SPRN_DPDES, 1);
vcpu->arch.vcore->dpdes = 1;
smp_wmb();
vcpu->arch.doorbell_request = 0;
}
}