// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2017 Paul Mackerras, IBM Corp. <[email protected]>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kvm_host.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
#include <asm/kvm_book3s_64.h>
#include <asm/reg.h>
#include <asm/ppc-opcode.h>
static void emulate_tx_failure(struct kvm_vcpu *vcpu, u64 failure_cause)
{
u64 texasr, tfiar;
u64 msr = vcpu->arch.shregs.msr;
tfiar = vcpu->arch.regs.nip & ~0x3ull;
texasr = (failure_cause << 56) | TEXASR_ABORT | TEXASR_FS | TEXASR_EXACT;
if (MSR_TM_SUSPENDED(vcpu->arch.shregs.msr))
texasr |= TEXASR_SUSP;
if (msr & MSR_PR) {
texasr |= TEXASR_PR;
tfiar |= 1;
}
vcpu->arch.tfiar = tfiar;
/* Preserve ROT and TL fields of existing TEXASR */
vcpu->arch.texasr = (vcpu->arch.texasr & 0x3ffffff) | texasr;
}
/*
* This gets called on a softpatch interrupt on POWER9 DD2.2 processors.
* We expect to find a TM-related instruction to be emulated. The
* instruction image is in vcpu->arch.emul_inst. If the guest was in
* TM suspended or transactional state, the checkpointed state has been
* reclaimed and is in the vcpu struct. The CPU is in virtual mode in
* host context.
*/
int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu)
{
u32 instr = vcpu->arch.emul_inst;
u64 msr = vcpu->arch.shregs.msr;
u64 newmsr, bescr;
int ra, rs;
/*
* The TM softpatch interrupt sets NIP to the instruction following
* the faulting instruction, which is not executed. Rewind nip to the
* faulting instruction so it looks like a normal synchronous
* interrupt, then update nip in the places where the instruction is
* emulated.
*/
vcpu->arch.regs.nip -= 4;
/*
* rfid, rfebb, and mtmsrd encode bit 31 = 0 since it's a reserved bit
* in these instructions, so masking bit 31 out doesn't change these
* instructions. For treclaim., tsr., and trechkpt. instructions if bit
* 31 = 0 then they are per ISA invalid forms, however P9 UM, in section
* 4.6.10 Book II Invalid Forms, informs specifically that ignoring bit
* 31 is an acceptable way to handle these invalid forms that have
* bit 31 = 0. Moreover, for emulation purposes both forms (w/ and wo/
* bit 31 set) can generate a softpatch interrupt. Hence both forms
* are handled below for these instructions so they behave the same way.
*/
switch (instr & PO_XOP_OPCODE_MASK) {
case PPC_INST_RFID:
/* XXX do we need to check for PR=0 here? */
newmsr = vcpu->arch.shregs.srr1;
/* should only get here for Sx -> T1 transition */
WARN_ON_ONCE(!(MSR_TM_SUSPENDED(msr) &&
MSR_TM_TRANSACTIONAL(newmsr) &&
(newmsr & MSR_TM)));
newmsr = sanitize_msr(newmsr);
vcpu->arch.shregs.msr = newmsr;
vcpu->arch.cfar = vcpu->arch.regs.nip;
vcpu->arch.regs.nip = vcpu->arch.shregs.srr0;
return RESUME_GUEST;
case PPC_INST_RFEBB:
if ((msr & MSR_PR) && (vcpu->arch.vcore->pcr & PCR_ARCH_206)) {
/* generate an illegal instruction interrupt */
kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
return RESUME_GUEST;
}
/* check EBB facility is available */
if (!(vcpu->arch.hfscr & HFSCR_EBB)) {
vcpu->arch.hfscr &= ~HFSCR_INTR_CAUSE;
vcpu->arch.hfscr |= (u64)FSCR_EBB_LG << 56;
vcpu->arch.trap = BOOK3S_INTERRUPT_H_FAC_UNAVAIL;
return -1; /* rerun host interrupt handler */
}
if ((msr & MSR_PR) && !(vcpu->arch.fscr & FSCR_EBB)) {
/* generate a facility unavailable interrupt */
vcpu->arch.fscr &= ~FSCR_INTR_CAUSE;
vcpu->arch.fscr |= (u64)FSCR_EBB_LG << 56;
kvmppc_book3s_queue_irqprio(vcpu, BOOK3S_INTERRUPT_FAC_UNAVAIL);
return RESUME_GUEST;
}
bescr = vcpu->arch.bescr;
/* expect to see a S->T transition requested */
WARN_ON_ONCE(!(MSR_TM_SUSPENDED(msr) &&
((bescr >> 30) & 3) == 2));
bescr &= ~BESCR_GE;
if (instr & (1 << 11))
bescr |= BESCR_GE;
vcpu->arch.bescr = bescr;
msr = (msr & ~MSR_TS_MASK) | MSR_TS_T;
vcpu->arch.shregs.msr = msr;
vcpu->arch.cfar = vcpu->arch.regs.nip;
vcpu->arch.regs.nip = vcpu->arch.ebbrr;
return RESUME_GUEST;
case PPC_INST_MTMSRD:
/* XXX do we need to check for PR=0 here? */
rs = (instr >> 21) & 0x1f;
newmsr = kvmppc_get_gpr(vcpu, rs);
/* check this is a Sx -> T1 transition */
WARN_ON_ONCE(!(MSR_TM_SUSPENDED(msr) &&
MSR_TM_TRANSACTIONAL(newmsr) &&
(newmsr & MSR_TM)));
/* mtmsrd doesn't change LE */
newmsr = (newmsr & ~MSR_LE) | (msr & MSR_LE);
newmsr = sanitize_msr(newmsr);
vcpu->arch.shregs.msr = newmsr;
vcpu->arch.regs.nip += 4;
return RESUME_GUEST;
/* ignore bit 31, see comment above */
case (PPC_INST_TSR & PO_XOP_OPCODE_MASK):
/* check for PR=1 and arch 2.06 bit set in PCR */
if ((msr & MSR_PR) && (vcpu->arch.vcore->pcr & PCR_ARCH_206)) {
/* generate an illegal instruction interrupt */
kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
return RESUME_GUEST;
}
/* check for TM disabled in the HFSCR or MSR */
if (!(vcpu->arch.hfscr & HFSCR_TM)) {
vcpu->arch.hfscr &= ~HFSCR_INTR_CAUSE;
vcpu->arch.hfscr |= (u64)FSCR_TM_LG << 56;
vcpu->arch.trap = BOOK3S_INTERRUPT_H_FAC_UNAVAIL;
return -1; /* rerun host interrupt handler */
}
if (!(msr & MSR_TM)) {
/* generate a facility unavailable interrupt */
vcpu->arch.fscr &= ~FSCR_INTR_CAUSE;
vcpu->arch.fscr |= (u64)FSCR_TM_LG << 56;
kvmppc_book3s_queue_irqprio(vcpu,
BOOK3S_INTERRUPT_FAC_UNAVAIL);
return RESUME_GUEST;
}
/* Set CR0 to indicate previous transactional state */
vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) |
(((msr & MSR_TS_MASK) >> MSR_TS_S_LG) << 29);
/* L=1 => tresume, L=0 => tsuspend */
if (instr & (1 << 21)) {
if (MSR_TM_SUSPENDED(msr))
msr = (msr & ~MSR_TS_MASK) | MSR_TS_T;
} else {
if (MSR_TM_TRANSACTIONAL(msr))
msr = (msr & ~MSR_TS_MASK) | MSR_TS_S;
}
vcpu->arch.shregs.msr = msr;
vcpu->arch.regs.nip += 4;
return RESUME_GUEST;
/* ignore bit 31, see comment above */
case (PPC_INST_TRECLAIM & PO_XOP_OPCODE_MASK):
/* check for TM disabled in the HFSCR or MSR */
if (!(vcpu->arch.hfscr & HFSCR_TM)) {
vcpu->arch.hfscr &= ~HFSCR_INTR_CAUSE;
vcpu->arch.hfscr |= (u64)FSCR_TM_LG << 56;
vcpu->arch.trap = BOOK3S_INTERRUPT_H_FAC_UNAVAIL;
return -1; /* rerun host interrupt handler */
}
if (!(msr & MSR_TM)) {
/* generate a facility unavailable interrupt */
vcpu->arch.fscr &= ~FSCR_INTR_CAUSE;
vcpu->arch.fscr |= (u64)FSCR_TM_LG << 56;
kvmppc_book3s_queue_irqprio(vcpu,
BOOK3S_INTERRUPT_FAC_UNAVAIL);
return RESUME_GUEST;
}
/* If no transaction active, generate TM bad thing */
if (!MSR_TM_ACTIVE(msr)) {
kvmppc_core_queue_program(vcpu, SRR1_PROGTM);
return RESUME_GUEST;
}
/* If failure was not previously recorded, recompute TEXASR */
if (!(vcpu->arch.orig_texasr & TEXASR_FS)) {
ra = (instr >> 16) & 0x1f;
if (ra)
ra = kvmppc_get_gpr(vcpu, ra) & 0xff;
emulate_tx_failure(vcpu, ra);
}
copy_from_checkpoint(vcpu);
/* Set CR0 to indicate previous transactional state */
vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) |
(((msr & MSR_TS_MASK) >> MSR_TS_S_LG) << 29);
vcpu->arch.shregs.msr &= ~MSR_TS_MASK;
vcpu->arch.regs.nip += 4;
return RESUME_GUEST;
/* ignore bit 31, see comment above */
case (PPC_INST_TRECHKPT & PO_XOP_OPCODE_MASK):
/* XXX do we need to check for PR=0 here? */
/* check for TM disabled in the HFSCR or MSR */
if (!(vcpu->arch.hfscr & HFSCR_TM)) {
vcpu->arch.hfscr &= ~HFSCR_INTR_CAUSE;
vcpu->arch.hfscr |= (u64)FSCR_TM_LG << 56;
vcpu->arch.trap = BOOK3S_INTERRUPT_H_FAC_UNAVAIL;
return -1; /* rerun host interrupt handler */
}
if (!(msr & MSR_TM)) {
/* generate a facility unavailable interrupt */
vcpu->arch.fscr &= ~FSCR_INTR_CAUSE;
vcpu->arch.fscr |= (u64)FSCR_TM_LG << 56;
kvmppc_book3s_queue_irqprio(vcpu,
BOOK3S_INTERRUPT_FAC_UNAVAIL);
return RESUME_GUEST;
}
/* If transaction active or TEXASR[FS] = 0, bad thing */
if (MSR_TM_ACTIVE(msr) || !(vcpu->arch.texasr & TEXASR_FS)) {
kvmppc_core_queue_program(vcpu, SRR1_PROGTM);
return RESUME_GUEST;
}
copy_to_checkpoint(vcpu);
/* Set CR0 to indicate previous transactional state */
vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) |
(((msr & MSR_TS_MASK) >> MSR_TS_S_LG) << 29);
vcpu->arch.shregs.msr = msr | MSR_TS_S;
vcpu->arch.regs.nip += 4;
return RESUME_GUEST;
}
/* What should we do here? We didn't recognize the instruction */
kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
pr_warn_ratelimited("Unrecognized TM-related instruction %#x for emulation", instr);
return RESUME_GUEST;
}
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