iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
0ba0e5d5a6
linux/arch/powerpc/kvm/book3s_hv_p9_entry.c
Nicholas Piggin 0ba0e5d5a6 KVM: PPC: Book3S HV: Split P8 from P9 path guest vCPU TLB flushing 
This creates separate functions for old and new paths for vCPU TLB
flushing, which will reduce complexity of the next change.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211123095231.1036501-43-npiggin@gmail.com
2021-11-24 21:09:01 +11:00

1134 lines
32 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/kernel.h>
#include <linux/kvm_host.h>
#include <asm/asm-prototypes.h>
#include <asm/dbell.h>
#include <asm/kvm_ppc.h>
#include <asm/pmc.h>
#include <asm/ppc-opcode.h>
#include "book3s_hv.h"
static void freeze_pmu(unsigned long mmcr0, unsigned long mmcra)
{
if (!(mmcr0 & MMCR0_FC))
goto do_freeze;
if (mmcra & MMCRA_SAMPLE_ENABLE)
goto do_freeze;
if (cpu_has_feature(CPU_FTR_ARCH_31)) {
if (!(mmcr0 & MMCR0_PMCCEXT))
goto do_freeze;
if (!(mmcra & MMCRA_BHRB_DISABLE))
goto do_freeze;
}
return;
do_freeze:
mmcr0 = MMCR0_FC;
mmcra = 0;
if (cpu_has_feature(CPU_FTR_ARCH_31)) {
mmcr0 |= MMCR0_PMCCEXT;
mmcra = MMCRA_BHRB_DISABLE;
}
mtspr(SPRN_MMCR0, mmcr0);
mtspr(SPRN_MMCRA, mmcra);
isync();
}
void switch_pmu_to_guest(struct kvm_vcpu *vcpu,
struct p9_host_os_sprs *host_os_sprs)
{
struct lppaca *lp;
int load_pmu = 1;
lp = vcpu->arch.vpa.pinned_addr;
if (lp)
load_pmu = lp->pmcregs_in_use;
/* Save host */
if (ppc_get_pmu_inuse()) {
/*
* It might be better to put PMU handling (at least for the
* host) in the perf subsystem because it knows more about what
* is being used.
*/
/* POWER9, POWER10 do not implement HPMC or SPMC */
host_os_sprs->mmcr0 = mfspr(SPRN_MMCR0);
host_os_sprs->mmcra = mfspr(SPRN_MMCRA);
freeze_pmu(host_os_sprs->mmcr0, host_os_sprs->mmcra);
host_os_sprs->pmc1 = mfspr(SPRN_PMC1);
host_os_sprs->pmc2 = mfspr(SPRN_PMC2);
host_os_sprs->pmc3 = mfspr(SPRN_PMC3);
host_os_sprs->pmc4 = mfspr(SPRN_PMC4);
host_os_sprs->pmc5 = mfspr(SPRN_PMC5);
host_os_sprs->pmc6 = mfspr(SPRN_PMC6);
host_os_sprs->mmcr1 = mfspr(SPRN_MMCR1);
host_os_sprs->mmcr2 = mfspr(SPRN_MMCR2);
host_os_sprs->sdar = mfspr(SPRN_SDAR);
host_os_sprs->siar = mfspr(SPRN_SIAR);
host_os_sprs->sier1 = mfspr(SPRN_SIER);
if (cpu_has_feature(CPU_FTR_ARCH_31)) {
host_os_sprs->mmcr3 = mfspr(SPRN_MMCR3);
host_os_sprs->sier2 = mfspr(SPRN_SIER2);
host_os_sprs->sier3 = mfspr(SPRN_SIER3);
}
}
#ifdef CONFIG_PPC_PSERIES
/* After saving PMU, before loading guest PMU, flip pmcregs_in_use */
if (kvmhv_on_pseries()) {
barrier();
get_lppaca()->pmcregs_in_use = load_pmu;
barrier();
}
#endif
/*
* Load guest. If the VPA said the PMCs are not in use but the guest
* tried to access them anyway, HFSCR[PM] will be set by the HFAC
* fault so we can make forward progress.
*/
if (load_pmu || (vcpu->arch.hfscr & HFSCR_PM)) {
mtspr(SPRN_PMC1, vcpu->arch.pmc[0]);
mtspr(SPRN_PMC2, vcpu->arch.pmc[1]);
mtspr(SPRN_PMC3, vcpu->arch.pmc[2]);
mtspr(SPRN_PMC4, vcpu->arch.pmc[3]);
mtspr(SPRN_PMC5, vcpu->arch.pmc[4]);
mtspr(SPRN_PMC6, vcpu->arch.pmc[5]);
mtspr(SPRN_MMCR1, vcpu->arch.mmcr[1]);
mtspr(SPRN_MMCR2, vcpu->arch.mmcr[2]);
mtspr(SPRN_SDAR, vcpu->arch.sdar);
mtspr(SPRN_SIAR, vcpu->arch.siar);
mtspr(SPRN_SIER, vcpu->arch.sier[0]);
if (cpu_has_feature(CPU_FTR_ARCH_31)) {
mtspr(SPRN_MMCR3, vcpu->arch.mmcr[3]);
mtspr(SPRN_SIER2, vcpu->arch.sier[1]);
mtspr(SPRN_SIER3, vcpu->arch.sier[2]);
}
/* Set MMCRA then MMCR0 last */
mtspr(SPRN_MMCRA, vcpu->arch.mmcra);
mtspr(SPRN_MMCR0, vcpu->arch.mmcr[0]);
/* No isync necessary because we're starting counters */
if (!vcpu->arch.nested &&
(vcpu->arch.hfscr_permitted & HFSCR_PM))
vcpu->arch.hfscr |= HFSCR_PM;
}
}
EXPORT_SYMBOL_GPL(switch_pmu_to_guest);
void switch_pmu_to_host(struct kvm_vcpu *vcpu,
struct p9_host_os_sprs *host_os_sprs)
{
struct lppaca *lp;
int save_pmu = 1;
lp = vcpu->arch.vpa.pinned_addr;
if (lp)
save_pmu = lp->pmcregs_in_use;
if (IS_ENABLED(CONFIG_KVM_BOOK3S_HV_NESTED_PMU_WORKAROUND)) {
/*
* Save pmu if this guest is capable of running nested guests.
* This is option is for old L1s that do not set their
* lppaca->pmcregs_in_use properly when entering their L2.
*/
save_pmu |= nesting_enabled(vcpu->kvm);
}
if (save_pmu) {
vcpu->arch.mmcr[0] = mfspr(SPRN_MMCR0);
vcpu->arch.mmcra = mfspr(SPRN_MMCRA);
freeze_pmu(vcpu->arch.mmcr[0], vcpu->arch.mmcra);
vcpu->arch.pmc[0] = mfspr(SPRN_PMC1);
vcpu->arch.pmc[1] = mfspr(SPRN_PMC2);
vcpu->arch.pmc[2] = mfspr(SPRN_PMC3);
vcpu->arch.pmc[3] = mfspr(SPRN_PMC4);
vcpu->arch.pmc[4] = mfspr(SPRN_PMC5);
vcpu->arch.pmc[5] = mfspr(SPRN_PMC6);
vcpu->arch.mmcr[1] = mfspr(SPRN_MMCR1);
vcpu->arch.mmcr[2] = mfspr(SPRN_MMCR2);
vcpu->arch.sdar = mfspr(SPRN_SDAR);
vcpu->arch.siar = mfspr(SPRN_SIAR);
vcpu->arch.sier[0] = mfspr(SPRN_SIER);
if (cpu_has_feature(CPU_FTR_ARCH_31)) {
vcpu->arch.mmcr[3] = mfspr(SPRN_MMCR3);
vcpu->arch.sier[1] = mfspr(SPRN_SIER2);
vcpu->arch.sier[2] = mfspr(SPRN_SIER3);
}
} else if (vcpu->arch.hfscr & HFSCR_PM) {
/*
* The guest accessed PMC SPRs without specifying they should
* be preserved, or it cleared pmcregs_in_use after the last
* access. Just ensure they are frozen.
*/
freeze_pmu(mfspr(SPRN_MMCR0), mfspr(SPRN_MMCRA));
/*
* Demand-fault PMU register access in the guest.
*
* This is used to grab the guest's VPA pmcregs_in_use value
* and reflect it into the host's VPA in the case of a nested
* hypervisor.
*
* It also avoids having to zero-out SPRs after each guest
* exit to avoid side-channels when.
*
* This is cleared here when we exit the guest, so later HFSCR
* interrupt handling can add it back to run the guest with
* PM enabled next time.
*/
if (!vcpu->arch.nested)
vcpu->arch.hfscr &= ~HFSCR_PM;
} /* otherwise the PMU should still be frozen */
#ifdef CONFIG_PPC_PSERIES
if (kvmhv_on_pseries()) {
barrier();
get_lppaca()->pmcregs_in_use = ppc_get_pmu_inuse();
barrier();
}
#endif
if (ppc_get_pmu_inuse()) {
mtspr(SPRN_PMC1, host_os_sprs->pmc1);
mtspr(SPRN_PMC2, host_os_sprs->pmc2);
mtspr(SPRN_PMC3, host_os_sprs->pmc3);
mtspr(SPRN_PMC4, host_os_sprs->pmc4);
mtspr(SPRN_PMC5, host_os_sprs->pmc5);
mtspr(SPRN_PMC6, host_os_sprs->pmc6);
mtspr(SPRN_MMCR1, host_os_sprs->mmcr1);
mtspr(SPRN_MMCR2, host_os_sprs->mmcr2);
mtspr(SPRN_SDAR, host_os_sprs->sdar);
mtspr(SPRN_SIAR, host_os_sprs->siar);
mtspr(SPRN_SIER, host_os_sprs->sier1);
if (cpu_has_feature(CPU_FTR_ARCH_31)) {
mtspr(SPRN_MMCR3, host_os_sprs->mmcr3);
mtspr(SPRN_SIER2, host_os_sprs->sier2);
mtspr(SPRN_SIER3, host_os_sprs->sier3);
}
/* Set MMCRA then MMCR0 last */
mtspr(SPRN_MMCRA, host_os_sprs->mmcra);
mtspr(SPRN_MMCR0, host_os_sprs->mmcr0);
isync();
}
}
EXPORT_SYMBOL_GPL(switch_pmu_to_host);
static void load_spr_state(struct kvm_vcpu *vcpu,
struct p9_host_os_sprs *host_os_sprs)
{
/* TAR is very fast */
mtspr(SPRN_TAR, vcpu->arch.tar);
#ifdef CONFIG_ALTIVEC
if (cpu_has_feature(CPU_FTR_ALTIVEC) &&
current->thread.vrsave != vcpu->arch.vrsave)
mtspr(SPRN_VRSAVE, vcpu->arch.vrsave);
#endif
if (vcpu->arch.hfscr & HFSCR_EBB) {
if (current->thread.ebbhr != vcpu->arch.ebbhr)
mtspr(SPRN_EBBHR, vcpu->arch.ebbhr);
if (current->thread.ebbrr != vcpu->arch.ebbrr)
mtspr(SPRN_EBBRR, vcpu->arch.ebbrr);
if (current->thread.bescr != vcpu->arch.bescr)
mtspr(SPRN_BESCR, vcpu->arch.bescr);
}
if (cpu_has_feature(CPU_FTR_P9_TIDR) &&
current->thread.tidr != vcpu->arch.tid)
mtspr(SPRN_TIDR, vcpu->arch.tid);
if (host_os_sprs->iamr != vcpu->arch.iamr)
mtspr(SPRN_IAMR, vcpu->arch.iamr);
if (host_os_sprs->amr != vcpu->arch.amr)
mtspr(SPRN_AMR, vcpu->arch.amr);
if (vcpu->arch.uamor != 0)
mtspr(SPRN_UAMOR, vcpu->arch.uamor);
if (current->thread.fscr != vcpu->arch.fscr)
mtspr(SPRN_FSCR, vcpu->arch.fscr);
if (current->thread.dscr != vcpu->arch.dscr)
mtspr(SPRN_DSCR, vcpu->arch.dscr);
if (vcpu->arch.pspb != 0)
mtspr(SPRN_PSPB, vcpu->arch.pspb);
/*
* DAR, DSISR, and for nested HV, SPRGs must be set with MSR[RI]
* clear (or hstate set appropriately to catch those registers
* being clobbered if we take a MCE or SRESET), so those are done
* later.
*/
if (!(vcpu->arch.ctrl & 1))
mtspr(SPRN_CTRLT, 0);
}
static void store_spr_state(struct kvm_vcpu *vcpu)
{
vcpu->arch.tar = mfspr(SPRN_TAR);
#ifdef CONFIG_ALTIVEC
if (cpu_has_feature(CPU_FTR_ALTIVEC))
vcpu->arch.vrsave = mfspr(SPRN_VRSAVE);
#endif
if (vcpu->arch.hfscr & HFSCR_EBB) {
vcpu->arch.ebbhr = mfspr(SPRN_EBBHR);
vcpu->arch.ebbrr = mfspr(SPRN_EBBRR);
vcpu->arch.bescr = mfspr(SPRN_BESCR);
}
if (cpu_has_feature(CPU_FTR_P9_TIDR))
vcpu->arch.tid = mfspr(SPRN_TIDR);
vcpu->arch.iamr = mfspr(SPRN_IAMR);
vcpu->arch.amr = mfspr(SPRN_AMR);
vcpu->arch.uamor = mfspr(SPRN_UAMOR);
vcpu->arch.fscr = mfspr(SPRN_FSCR);
vcpu->arch.dscr = mfspr(SPRN_DSCR);
vcpu->arch.pspb = mfspr(SPRN_PSPB);
vcpu->arch.ctrl = mfspr(SPRN_CTRLF);
}
/* Returns true if current MSR and/or guest MSR may have changed */
bool load_vcpu_state(struct kvm_vcpu *vcpu,
struct p9_host_os_sprs *host_os_sprs)
{
bool ret = false;
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
if (cpu_has_feature(CPU_FTR_TM) ||
cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) {
unsigned long guest_msr = vcpu->arch.shregs.msr;
if (MSR_TM_ACTIVE(guest_msr)) {
kvmppc_restore_tm_hv(vcpu, guest_msr, true);
ret = true;
} else if (vcpu->arch.hfscr & HFSCR_TM) {
mtspr(SPRN_TEXASR, vcpu->arch.texasr);
mtspr(SPRN_TFHAR, vcpu->arch.tfhar);
mtspr(SPRN_TFIAR, vcpu->arch.tfiar);
}
}
#endif
load_spr_state(vcpu, host_os_sprs);
load_fp_state(&vcpu->arch.fp);
#ifdef CONFIG_ALTIVEC
load_vr_state(&vcpu->arch.vr);
#endif
return ret;
}
EXPORT_SYMBOL_GPL(load_vcpu_state);
void store_vcpu_state(struct kvm_vcpu *vcpu)
{
store_spr_state(vcpu);
store_fp_state(&vcpu->arch.fp);
#ifdef CONFIG_ALTIVEC
store_vr_state(&vcpu->arch.vr);
#endif
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
if (cpu_has_feature(CPU_FTR_TM) ||
cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) {
unsigned long guest_msr = vcpu->arch.shregs.msr;
if (MSR_TM_ACTIVE(guest_msr)) {
kvmppc_save_tm_hv(vcpu, guest_msr, true);
} else if (vcpu->arch.hfscr & HFSCR_TM) {
vcpu->arch.texasr = mfspr(SPRN_TEXASR);
vcpu->arch.tfhar = mfspr(SPRN_TFHAR);
vcpu->arch.tfiar = mfspr(SPRN_TFIAR);
if (!vcpu->arch.nested) {
vcpu->arch.load_tm++; /* see load_ebb comment */
if (!vcpu->arch.load_tm)
vcpu->arch.hfscr &= ~HFSCR_TM;
}
}
}
#endif
}
EXPORT_SYMBOL_GPL(store_vcpu_state);
void save_p9_host_os_sprs(struct p9_host_os_sprs *host_os_sprs)
{
host_os_sprs->iamr = mfspr(SPRN_IAMR);
host_os_sprs->amr = mfspr(SPRN_AMR);
}
EXPORT_SYMBOL_GPL(save_p9_host_os_sprs);
/* vcpu guest regs must already be saved */
void restore_p9_host_os_sprs(struct kvm_vcpu *vcpu,
struct p9_host_os_sprs *host_os_sprs)
{
/*
* current->thread.xxx registers must all be restored to host
* values before a potential context switch, othrewise the context
* switch itself will overwrite current->thread.xxx with the values
* from the guest SPRs.
*/
mtspr(SPRN_SPRG_VDSO_WRITE, local_paca->sprg_vdso);
if (cpu_has_feature(CPU_FTR_P9_TIDR) &&
current->thread.tidr != vcpu->arch.tid)
mtspr(SPRN_TIDR, current->thread.tidr);
if (host_os_sprs->iamr != vcpu->arch.iamr)
mtspr(SPRN_IAMR, host_os_sprs->iamr);
if (vcpu->arch.uamor != 0)
mtspr(SPRN_UAMOR, 0);
if (host_os_sprs->amr != vcpu->arch.amr)
mtspr(SPRN_AMR, host_os_sprs->amr);
if (current->thread.fscr != vcpu->arch.fscr)
mtspr(SPRN_FSCR, current->thread.fscr);
if (current->thread.dscr != vcpu->arch.dscr)
mtspr(SPRN_DSCR, current->thread.dscr);
if (vcpu->arch.pspb != 0)
mtspr(SPRN_PSPB, 0);
/* Save guest CTRL register, set runlatch to 1 */
if (!(vcpu->arch.ctrl & 1))
mtspr(SPRN_CTRLT, 1);
#ifdef CONFIG_ALTIVEC
if (cpu_has_feature(CPU_FTR_ALTIVEC) &&
vcpu->arch.vrsave != current->thread.vrsave)
mtspr(SPRN_VRSAVE, current->thread.vrsave);
#endif
if (vcpu->arch.hfscr & HFSCR_EBB) {
if (vcpu->arch.bescr != current->thread.bescr)
mtspr(SPRN_BESCR, current->thread.bescr);
if (vcpu->arch.ebbhr != current->thread.ebbhr)
mtspr(SPRN_EBBHR, current->thread.ebbhr);
if (vcpu->arch.ebbrr != current->thread.ebbrr)
mtspr(SPRN_EBBRR, current->thread.ebbrr);
if (!vcpu->arch.nested) {
/*
* This is like load_fp in context switching, turn off
* the facility after it wraps the u8 to try avoiding
* saving and restoring the registers each partition
* switch.
*/
vcpu->arch.load_ebb++;
if (!vcpu->arch.load_ebb)
vcpu->arch.hfscr &= ~HFSCR_EBB;
}
}
if (vcpu->arch.tar != current->thread.tar)
mtspr(SPRN_TAR, current->thread.tar);
}
EXPORT_SYMBOL_GPL(restore_p9_host_os_sprs);
#ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
static void __start_timing(struct kvm_vcpu *vcpu, struct kvmhv_tb_accumulator *next)
{
struct kvmppc_vcore *vc = vcpu->arch.vcore;
u64 tb = mftb() - vc->tb_offset_applied;
vcpu->arch.cur_activity = next;
vcpu->arch.cur_tb_start = tb;
}
static void __accumulate_time(struct kvm_vcpu *vcpu, struct kvmhv_tb_accumulator *next)
{
struct kvmppc_vcore *vc = vcpu->arch.vcore;
struct kvmhv_tb_accumulator *curr;
u64 tb = mftb() - vc->tb_offset_applied;
u64 prev_tb;
u64 delta;
u64 seq;
curr = vcpu->arch.cur_activity;
vcpu->arch.cur_activity = next;
prev_tb = vcpu->arch.cur_tb_start;
vcpu->arch.cur_tb_start = tb;
if (!curr)
return;
delta = tb - prev_tb;
seq = curr->seqcount;
curr->seqcount = seq + 1;
smp_wmb();
curr->tb_total += delta;
if (seq == 0 || delta < curr->tb_min)
curr->tb_min = delta;
if (delta > curr->tb_max)
curr->tb_max = delta;
smp_wmb();
curr->seqcount = seq + 2;
}
#define start_timing(vcpu, next) __start_timing(vcpu, next)
#define end_timing(vcpu) __start_timing(vcpu, NULL)
#define accumulate_time(vcpu, next) __accumulate_time(vcpu, next)
#else
#define start_timing(vcpu, next) do {} while (0)
#define end_timing(vcpu) do {} while (0)
#define accumulate_time(vcpu, next) do {} while (0)
#endif
static inline void mfslb(unsigned int idx, u64 *slbee, u64 *slbev)
{
asm volatile("slbmfev %0,%1" : "=r" (*slbev) : "r" (idx));
asm volatile("slbmfee %0,%1" : "=r" (*slbee) : "r" (idx));
}
static inline void mtslb(u64 slbee, u64 slbev)
{
asm volatile("slbmte %0,%1" :: "r" (slbev), "r" (slbee));
}
static inline void clear_slb_entry(unsigned int idx)
{
mtslb(idx, 0);
}
static inline void slb_clear_invalidate_partition(void)
{
clear_slb_entry(0);
asm volatile(PPC_SLBIA(6));
}
/*
* Malicious or buggy radix guests may have inserted SLB entries
* (only 0..3 because radix always runs with UPRT=1), so these must
* be cleared here to avoid side-channels. slbmte is used rather
* than slbia, as it won't clear cached translations.
*/
static void radix_clear_slb(void)
{
int i;
for (i = 0; i < 4; i++)
clear_slb_entry(i);
}
static void switch_mmu_to_guest_radix(struct kvm *kvm, struct kvm_vcpu *vcpu, u64 lpcr)
{
struct kvm_nested_guest *nested = vcpu->arch.nested;
u32 lpid;
lpid = nested ? nested->shadow_lpid : kvm->arch.lpid;
/*
* Prior memory accesses to host PID Q3 must be completed before we
* start switching, and stores must be drained to avoid not-my-LPAR
* logic (see switch_mmu_to_host).
*/
asm volatile("hwsync" ::: "memory");
isync();
mtspr(SPRN_LPID, lpid);
mtspr(SPRN_LPCR, lpcr);
mtspr(SPRN_PID, vcpu->arch.pid);
/*
* isync not required here because we are HRFID'ing to guest before
* any guest context access, which is context synchronising.
*/
}
static void switch_mmu_to_guest_hpt(struct kvm *kvm, struct kvm_vcpu *vcpu, u64 lpcr)
{
u32 lpid;
int i;
lpid = kvm->arch.lpid;
/*
* See switch_mmu_to_guest_radix. ptesync should not be required here
* even if the host is in HPT mode because speculative accesses would
* not cause RC updates (we are in real mode).
*/
asm volatile("hwsync" ::: "memory");
isync();
mtspr(SPRN_LPID, lpid);
mtspr(SPRN_LPCR, lpcr);
mtspr(SPRN_PID, vcpu->arch.pid);
for (i = 0; i < vcpu->arch.slb_max; i++)
mtslb(vcpu->arch.slb[i].orige, vcpu->arch.slb[i].origv);
/*
* isync not required here, see switch_mmu_to_guest_radix.
*/
}
static void switch_mmu_to_host(struct kvm *kvm, u32 pid)
{
/*
* The guest has exited, so guest MMU context is no longer being
* non-speculatively accessed, but a hwsync is needed before the
* mtLPIDR / mtPIDR switch, in order to ensure all stores are drained,
* so the not-my-LPAR tlbie logic does not overlook them.
*/
asm volatile("hwsync" ::: "memory");
isync();
mtspr(SPRN_PID, pid);
mtspr(SPRN_LPID, kvm->arch.host_lpid);
mtspr(SPRN_LPCR, kvm->arch.host_lpcr);
/*
* isync is not required after the switch, because mtmsrd with L=0
* is performed after this switch, which is context synchronising.
*/
if (!radix_enabled())
slb_restore_bolted_realmode();
}
static void save_clear_host_mmu(struct kvm *kvm)
{
if (!radix_enabled()) {
/*
* Hash host could save and restore host SLB entries to
* reduce SLB fault overheads of VM exits, but for now the
* existing code clears all entries and restores just the
* bolted ones when switching back to host.
*/
slb_clear_invalidate_partition();
}
}
static void save_clear_guest_mmu(struct kvm *kvm, struct kvm_vcpu *vcpu)
{
if (kvm_is_radix(kvm)) {
radix_clear_slb();
} else {
int i;
int nr = 0;
/*
* This must run before switching to host (radix host can't
* access all SLBs).
*/
for (i = 0; i < vcpu->arch.slb_nr; i++) {
u64 slbee, slbev;
mfslb(i, &slbee, &slbev);
if (slbee & SLB_ESID_V) {
vcpu->arch.slb[nr].orige = slbee | i;
vcpu->arch.slb[nr].origv = slbev;
nr++;
}
}
vcpu->arch.slb_max = nr;
slb_clear_invalidate_partition();
}
}
static void flush_guest_tlb(struct kvm *kvm)
{
unsigned long rb, set;
rb = PPC_BIT(52); /* IS = 2 */
if (kvm_is_radix(kvm)) {
/* R=1 PRS=1 RIC=2 */
asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
: : "r" (rb), "i" (1), "i" (1), "i" (2),
"r" (0) : "memory");
for (set = 1; set < kvm->arch.tlb_sets; ++set) {
rb += PPC_BIT(51); /* increment set number */
/* R=1 PRS=1 RIC=0 */
asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
: : "r" (rb), "i" (1), "i" (1), "i" (0),
"r" (0) : "memory");
}
asm volatile("ptesync": : :"memory");
// POWER9 congruence-class TLBIEL leaves ERAT. Flush it now.
asm volatile(PPC_RADIX_INVALIDATE_ERAT_GUEST : : :"memory");
} else {
for (set = 0; set < kvm->arch.tlb_sets; ++set) {
/* R=0 PRS=0 RIC=0 */
asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
: : "r" (rb), "i" (0), "i" (0), "i" (0),
"r" (0) : "memory");
rb += PPC_BIT(51); /* increment set number */
}
asm volatile("ptesync": : :"memory");
// POWER9 congruence-class TLBIEL leaves ERAT. Flush it now.
asm volatile(PPC_ISA_3_0_INVALIDATE_ERAT : : :"memory");
}
}
static void check_need_tlb_flush(struct kvm *kvm, int pcpu,
struct kvm_nested_guest *nested)
{
cpumask_t *need_tlb_flush;
/*
* On POWER9, individual threads can come in here, but the
* TLB is shared between the 4 threads in a core, hence
* invalidating on one thread invalidates for all.
* Thus we make all 4 threads use the same bit.
*/
pcpu = cpu_first_tlb_thread_sibling(pcpu);
if (nested)
need_tlb_flush = &nested->need_tlb_flush;
else
need_tlb_flush = &kvm->arch.need_tlb_flush;
if (cpumask_test_cpu(pcpu, need_tlb_flush)) {
flush_guest_tlb(kvm);
/* Clear the bit after the TLB flush */
cpumask_clear_cpu(pcpu, need_tlb_flush);
}
}
int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpcr, u64 *tb)
{
struct p9_host_os_sprs host_os_sprs;
struct kvm *kvm = vcpu->kvm;
struct kvm_nested_guest *nested = vcpu->arch.nested;
struct kvmppc_vcore *vc = vcpu->arch.vcore;
s64 hdec, dec;
u64 purr, spurr;
u64 *exsave;
bool ri_set;
int trap;
unsigned long msr;
unsigned long host_hfscr;
unsigned long host_ciabr;
unsigned long host_dawr0;
unsigned long host_dawrx0;
unsigned long host_psscr;
unsigned long host_hpsscr;
unsigned long host_pidr;
unsigned long host_dawr1;
unsigned long host_dawrx1;
hdec = time_limit - *tb;
if (hdec < 0)
return BOOK3S_INTERRUPT_HV_DECREMENTER;
WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_HV);
WARN_ON_ONCE(!(vcpu->arch.shregs.msr & MSR_ME));
start_timing(vcpu, &vcpu->arch.rm_entry);
vcpu->arch.ceded = 0;
host_hfscr = mfspr(SPRN_HFSCR);
host_ciabr = mfspr(SPRN_CIABR);
host_psscr = mfspr(SPRN_PSSCR_PR);
if (cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST))
host_hpsscr = mfspr(SPRN_PSSCR);
host_pidr = mfspr(SPRN_PID);
if (dawr_enabled()) {
host_dawr0 = mfspr(SPRN_DAWR0);
host_dawrx0 = mfspr(SPRN_DAWRX0);
if (cpu_has_feature(CPU_FTR_DAWR1)) {
host_dawr1 = mfspr(SPRN_DAWR1);
host_dawrx1 = mfspr(SPRN_DAWRX1);
}
}
local_paca->kvm_hstate.host_purr = mfspr(SPRN_PURR);
local_paca->kvm_hstate.host_spurr = mfspr(SPRN_SPURR);
save_p9_host_os_sprs(&host_os_sprs);
/*
* This could be combined with MSR[RI] clearing, but that expands
* the unrecoverable window. It would be better to cover unrecoverable
* with KVM bad interrupt handling rather than use MSR[RI] at all.
*
* Much more difficult and less worthwhile to combine with IR/DR
* disable.
*/
hard_irq_disable();
if (lazy_irq_pending()) {
trap = 0;
goto out;
}
/* MSR bits may have been cleared by context switch */
msr = 0;
if (IS_ENABLED(CONFIG_PPC_FPU))
msr |= MSR_FP;
if (cpu_has_feature(CPU_FTR_ALTIVEC))
msr |= MSR_VEC;
if (cpu_has_feature(CPU_FTR_VSX))
msr |= MSR_VSX;
if ((cpu_has_feature(CPU_FTR_TM) ||
cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) &&
(vcpu->arch.hfscr & HFSCR_TM))
msr |= MSR_TM;
msr = msr_check_and_set(msr);
/* Save MSR for restore. This is after hard disable, so EE is clear. */
if (unlikely(load_vcpu_state(vcpu, &host_os_sprs)))
msr = mfmsr(); /* MSR may have been updated */
if (vc->tb_offset) {
u64 new_tb = *tb + vc->tb_offset;
mtspr(SPRN_TBU40, new_tb);
if ((mftb() & 0xffffff) < (new_tb & 0xffffff)) {
new_tb += 0x1000000;
mtspr(SPRN_TBU40, new_tb);
}
*tb = new_tb;
vc->tb_offset_applied = vc->tb_offset;
}
mtspr(SPRN_VTB, vc->vtb);
mtspr(SPRN_PURR, vcpu->arch.purr);
mtspr(SPRN_SPURR, vcpu->arch.spurr);
if (vc->pcr)
mtspr(SPRN_PCR, vc->pcr | PCR_MASK);
if (vc->dpdes)
mtspr(SPRN_DPDES, vc->dpdes);
if (dawr_enabled()) {
if (vcpu->arch.dawr0 != host_dawr0)
mtspr(SPRN_DAWR0, vcpu->arch.dawr0);
if (vcpu->arch.dawrx0 != host_dawrx0)
mtspr(SPRN_DAWRX0, vcpu->arch.dawrx0);
if (cpu_has_feature(CPU_FTR_DAWR1)) {
if (vcpu->arch.dawr1 != host_dawr1)
mtspr(SPRN_DAWR1, vcpu->arch.dawr1);
if (vcpu->arch.dawrx1 != host_dawrx1)
mtspr(SPRN_DAWRX1, vcpu->arch.dawrx1);
}
}
if (vcpu->arch.ciabr != host_ciabr)
mtspr(SPRN_CIABR, vcpu->arch.ciabr);
if (cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) {
mtspr(SPRN_PSSCR, vcpu->arch.psscr | PSSCR_EC |
(local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
} else {
if (vcpu->arch.psscr != host_psscr)
mtspr(SPRN_PSSCR_PR, vcpu->arch.psscr);
}
mtspr(SPRN_HFSCR, vcpu->arch.hfscr);
mtspr(SPRN_HSRR0, vcpu->arch.regs.nip);
mtspr(SPRN_HSRR1, (vcpu->arch.shregs.msr & ~MSR_HV) | MSR_ME);
/*
* On POWER9 DD2.1 and below, sometimes on a Hypervisor Data Storage
* Interrupt (HDSI) the HDSISR is not be updated at all.
*
* To work around this we put a canary value into the HDSISR before
* returning to a guest and then check for this canary when we take a
* HDSI. If we find the canary on a HDSI, we know the hardware didn't
* update the HDSISR. In this case we return to the guest to retake the
* HDSI which should correctly update the HDSISR the second time HDSI
* entry.
*
* The "radix prefetch bug" test can be used to test for this bug, as
* it also exists fo DD2.1 and below.
*/
if (cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
mtspr(SPRN_HDSISR, HDSISR_CANARY);
mtspr(SPRN_SPRG0, vcpu->arch.shregs.sprg0);
mtspr(SPRN_SPRG1, vcpu->arch.shregs.sprg1);
mtspr(SPRN_SPRG2, vcpu->arch.shregs.sprg2);
mtspr(SPRN_SPRG3, vcpu->arch.shregs.sprg3);
/*
* It might be preferable to load_vcpu_state here, in order to get the
* GPR/FP register loads executing in parallel with the previous mtSPR
* instructions, but for now that can't be done because the TM handling
* in load_vcpu_state can change some SPRs and vcpu state (nip, msr).
* But TM could be split out if this would be a significant benefit.
*/
local_paca->kvm_hstate.in_guest = KVM_GUEST_MODE_HV_P9;
/*
* Hash host, hash guest, or radix guest with prefetch bug, all have
* to disable the MMU before switching to guest MMU state.
*/
if (!radix_enabled() || !kvm_is_radix(kvm) ||
cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
__mtmsrd(msr & ~(MSR_IR|MSR_DR|MSR_RI), 0);
save_clear_host_mmu(kvm);
if (kvm_is_radix(kvm)) {
switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
if (!cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
__mtmsrd(0, 1); /* clear RI */
} else {
switch_mmu_to_guest_hpt(kvm, vcpu, lpcr);
}
/* TLBIEL uses LPID=LPIDR, so run this after setting guest LPID */
check_need_tlb_flush(kvm, vc->pcpu, nested);
/*
* P9 suppresses the HDEC exception when LPCR[HDICE] = 0,
* so set guest LPCR (with HDICE) before writing HDEC.
*/
mtspr(SPRN_HDEC, hdec);
mtspr(SPRN_DEC, vcpu->arch.dec_expires - *tb);
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
tm_return_to_guest:
#endif
mtspr(SPRN_DAR, vcpu->arch.shregs.dar);
mtspr(SPRN_DSISR, vcpu->arch.shregs.dsisr);
mtspr(SPRN_SRR0, vcpu->arch.shregs.srr0);
mtspr(SPRN_SRR1, vcpu->arch.shregs.srr1);
accumulate_time(vcpu, &vcpu->arch.guest_time);
switch_pmu_to_guest(vcpu, &host_os_sprs);
kvmppc_p9_enter_guest(vcpu);
switch_pmu_to_host(vcpu, &host_os_sprs);
accumulate_time(vcpu, &vcpu->arch.rm_intr);
/* XXX: Could get these from r11/12 and paca exsave instead */
vcpu->arch.shregs.srr0 = mfspr(SPRN_SRR0);
vcpu->arch.shregs.srr1 = mfspr(SPRN_SRR1);
vcpu->arch.shregs.dar = mfspr(SPRN_DAR);
vcpu->arch.shregs.dsisr = mfspr(SPRN_DSISR);
/* 0x2 bit for HSRR is only used by PR and P7/8 HV paths, clear it */
trap = local_paca->kvm_hstate.scratch0 & ~0x2;
/* HSRR interrupts leave MSR[RI] unchanged, SRR interrupts clear it. */
ri_set = false;
if (likely(trap > BOOK3S_INTERRUPT_MACHINE_CHECK)) {
if (trap != BOOK3S_INTERRUPT_SYSCALL &&
(vcpu->arch.shregs.msr & MSR_RI))
ri_set = true;
exsave = local_paca->exgen;
} else if (trap == BOOK3S_INTERRUPT_SYSTEM_RESET) {
exsave = local_paca->exnmi;
} else { /* trap == 0x200 */
exsave = local_paca->exmc;
}
vcpu->arch.regs.gpr[1] = local_paca->kvm_hstate.scratch1;
vcpu->arch.regs.gpr[3] = local_paca->kvm_hstate.scratch2;
/*
* Only set RI after reading machine check regs (DAR, DSISR, SRR0/1)
* and hstate scratch (which we need to move into exsave to make
* re-entrant vs SRESET/MCE)
*/
if (ri_set) {
if (unlikely(!(mfmsr() & MSR_RI))) {
__mtmsrd(MSR_RI, 1);
WARN_ON_ONCE(1);
}
} else {
WARN_ON_ONCE(mfmsr() & MSR_RI);
__mtmsrd(MSR_RI, 1);
}
vcpu->arch.regs.gpr[9] = exsave[EX_R9/sizeof(u64)];
vcpu->arch.regs.gpr[10] = exsave[EX_R10/sizeof(u64)];
vcpu->arch.regs.gpr[11] = exsave[EX_R11/sizeof(u64)];
vcpu->arch.regs.gpr[12] = exsave[EX_R12/sizeof(u64)];
vcpu->arch.regs.gpr[13] = exsave[EX_R13/sizeof(u64)];
vcpu->arch.ppr = exsave[EX_PPR/sizeof(u64)];
vcpu->arch.cfar = exsave[EX_CFAR/sizeof(u64)];
vcpu->arch.regs.ctr = exsave[EX_CTR/sizeof(u64)];
vcpu->arch.last_inst = KVM_INST_FETCH_FAILED;
if (unlikely(trap == BOOK3S_INTERRUPT_MACHINE_CHECK)) {
vcpu->arch.fault_dar = exsave[EX_DAR/sizeof(u64)];
vcpu->arch.fault_dsisr = exsave[EX_DSISR/sizeof(u64)];
kvmppc_realmode_machine_check(vcpu);
} else if (unlikely(trap == BOOK3S_INTERRUPT_HMI)) {
kvmppc_realmode_hmi_handler();
} else if (trap == BOOK3S_INTERRUPT_H_EMUL_ASSIST) {
vcpu->arch.emul_inst = mfspr(SPRN_HEIR);
} else if (trap == BOOK3S_INTERRUPT_H_DATA_STORAGE) {
vcpu->arch.fault_dar = exsave[EX_DAR/sizeof(u64)];
vcpu->arch.fault_dsisr = exsave[EX_DSISR/sizeof(u64)];
vcpu->arch.fault_gpa = mfspr(SPRN_ASDR);
} else if (trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
vcpu->arch.fault_gpa = mfspr(SPRN_ASDR);
} else if (trap == BOOK3S_INTERRUPT_H_FAC_UNAVAIL) {
vcpu->arch.hfscr = mfspr(SPRN_HFSCR);
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
/*
* Softpatch interrupt for transactional memory emulation cases
* on POWER9 DD2.2. This is early in the guest exit path - we
* haven't saved registers or done a treclaim yet.
*/
} else if (trap == BOOK3S_INTERRUPT_HV_SOFTPATCH) {
vcpu->arch.emul_inst = mfspr(SPRN_HEIR);
/*
* The cases we want to handle here are those where the guest
* is in real suspend mode and is trying to transition to
* transactional mode.
*/
if (!local_paca->kvm_hstate.fake_suspend &&
(vcpu->arch.shregs.msr & MSR_TS_S)) {
if (kvmhv_p9_tm_emulation_early(vcpu)) {
/*
* Go straight back into the guest with the
* new NIP/MSR as set by TM emulation.
*/
mtspr(SPRN_HSRR0, vcpu->arch.regs.nip);
mtspr(SPRN_HSRR1, vcpu->arch.shregs.msr);
/*
* tm_return_to_guest re-loads SRR0/1, DAR,
* DSISR after RI is cleared, in case they had
* been clobbered by a MCE.
*/
__mtmsrd(0, 1); /* clear RI */
goto tm_return_to_guest;
}
}
#endif
}
accumulate_time(vcpu, &vcpu->arch.rm_exit);
/* Advance host PURR/SPURR by the amount used by guest */
purr = mfspr(SPRN_PURR);
spurr = mfspr(SPRN_SPURR);
local_paca->kvm_hstate.host_purr += purr - vcpu->arch.purr;
local_paca->kvm_hstate.host_spurr += spurr - vcpu->arch.spurr;
vcpu->arch.purr = purr;
vcpu->arch.spurr = spurr;
vcpu->arch.ic = mfspr(SPRN_IC);
vcpu->arch.pid = mfspr(SPRN_PID);
vcpu->arch.psscr = mfspr(SPRN_PSSCR_PR);
vcpu->arch.shregs.sprg0 = mfspr(SPRN_SPRG0);
vcpu->arch.shregs.sprg1 = mfspr(SPRN_SPRG1);
vcpu->arch.shregs.sprg2 = mfspr(SPRN_SPRG2);
vcpu->arch.shregs.sprg3 = mfspr(SPRN_SPRG3);
vc->dpdes = mfspr(SPRN_DPDES);
vc->vtb = mfspr(SPRN_VTB);
dec = mfspr(SPRN_DEC);
if (!(lpcr & LPCR_LD)) /* Sign extend if not using large decrementer */
dec = (s32) dec;
*tb = mftb();
vcpu->arch.dec_expires = dec + *tb;
if (vc->tb_offset_applied) {
u64 new_tb = *tb - vc->tb_offset_applied;
mtspr(SPRN_TBU40, new_tb);
if ((mftb() & 0xffffff) < (new_tb & 0xffffff)) {
new_tb += 0x1000000;
mtspr(SPRN_TBU40, new_tb);
}
*tb = new_tb;
vc->tb_offset_applied = 0;
}
save_clear_guest_mmu(kvm, vcpu);
switch_mmu_to_host(kvm, host_pidr);
/*
* Enable MSR here in order to have facilities enabled to save
* guest registers. This enables MMU (if we were in realmode), so
* only switch MMU on after the MMU is switched to host, to avoid
* the P9_RADIX_PREFETCH_BUG or hash guest context.
*/
if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) &&
vcpu->arch.shregs.msr & MSR_TS_MASK)
msr |= MSR_TS_S;
__mtmsrd(msr, 0);
store_vcpu_state(vcpu);
mtspr(SPRN_PURR, local_paca->kvm_hstate.host_purr);
mtspr(SPRN_SPURR, local_paca->kvm_hstate.host_spurr);
if (cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) {
/* Preserve PSSCR[FAKE_SUSPEND] until we've called kvmppc_save_tm_hv */
mtspr(SPRN_PSSCR, host_hpsscr |
(local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
}
mtspr(SPRN_HFSCR, host_hfscr);
if (vcpu->arch.ciabr != host_ciabr)
mtspr(SPRN_CIABR, host_ciabr);
if (dawr_enabled()) {
if (vcpu->arch.dawr0 != host_dawr0)
mtspr(SPRN_DAWR0, host_dawr0);
if (vcpu->arch.dawrx0 != host_dawrx0)
mtspr(SPRN_DAWRX0, host_dawrx0);
if (cpu_has_feature(CPU_FTR_DAWR1)) {
if (vcpu->arch.dawr1 != host_dawr1)
mtspr(SPRN_DAWR1, host_dawr1);
if (vcpu->arch.dawrx1 != host_dawrx1)
mtspr(SPRN_DAWRX1, host_dawrx1);
}
}
if (vc->dpdes)
mtspr(SPRN_DPDES, 0);
if (vc->pcr)
mtspr(SPRN_PCR, PCR_MASK);
/* HDEC must be at least as large as DEC, so decrementer_max fits */
mtspr(SPRN_HDEC, decrementer_max);
timer_rearm_host_dec(*tb);
restore_p9_host_os_sprs(vcpu, &host_os_sprs);
local_paca->kvm_hstate.in_guest = KVM_GUEST_MODE_NONE;
if (kvm_is_radix(kvm)) {
/*
* Since this is radix, do a eieio; tlbsync; ptesync sequence
* in case we interrupted the guest between a tlbie and a
* ptesync.
*/
asm volatile("eieio; tlbsync; ptesync");
}
/*
* cp_abort is required if the processor supports local copy-paste
* to clear the copy buffer that was under control of the guest.
*/
if (cpu_has_feature(CPU_FTR_ARCH_31))
asm volatile(PPC_CP_ABORT);
out:
end_timing(vcpu);
return trap;
}
EXPORT_SYMBOL_GPL(kvmhv_vcpu_entry_p9);
Reference in New Issue View Git Blame Copy Permalink