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Diffstat (limited to '')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_tm.c | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_tm.c b/arch/powerpc/kvm/book3s_hv_tm.c new file mode 100644 index 0000000000..866cadd700 --- /dev/null +++ b/arch/powerpc/kvm/book3s_hv_tm.c @@ -0,0 +1,248 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2017 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> + */ + +#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; +} |