arch/powerpc/kvm/book3s_hv_tm.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright 2017 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
  */

 #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;

 	switch (instr & 0xfc0007ff) {
 	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 - 4;
 		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)) {
 			/* generate an illegal instruction interrupt */
 			kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
 			return RESUME_GUEST;
 		}
 		if ((msr & MSR_PR) && !(vcpu->arch.fscr & FSCR_EBB)) {
 			/* generate a facility unavailable interrupt */
 			vcpu->arch.fscr = (vcpu->arch.fscr & ~(0xffull << 56)) |
 				((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 - 4;
 		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;
 		return RESUME_GUEST;

 	case PPC_INST_TSR:
 		/* 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)) {
 			/* generate an illegal instruction interrupt */
 			kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
 			return RESUME_GUEST;
 		}
 		if (!(msr & MSR_TM)) {
 			/* generate a facility unavailable interrupt */
 			vcpu->arch.fscr = (vcpu->arch.fscr & ~(0xffull << 56)) |
 				((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;
 		return RESUME_GUEST;

 	case PPC_INST_TRECLAIM:
 		/* check for TM disabled in the HFSCR or MSR */
 		if (!(vcpu->arch.hfscr & HFSCR_TM)) {
 			/* generate an illegal instruction interrupt */
 			kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
 			return RESUME_GUEST;
 		}
 		if (!(msr & MSR_TM)) {
 			/* generate a facility unavailable interrupt */
 			vcpu->arch.fscr = (vcpu->arch.fscr & ~(0xffull << 56)) |
 				((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;
 		return RESUME_GUEST;

 	case PPC_INST_TRECHKPT:
 		/* 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)) {
 			/* generate an illegal instruction interrupt */
 			kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
 			return RESUME_GUEST;
 		}
 		if (!(msr & MSR_TM)) {
 			/* generate a facility unavailable interrupt */
 			vcpu->arch.fscr = (vcpu->arch.fscr & ~(0xffull << 56)) |
 				((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;
 		return RESUME_GUEST;
 	}

 	/* What should we do here? We didn't recognize the instruction */
 	WARN_ON_ONCE(1);
 	return RESUME_GUEST;
 }
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* Copyright 2017 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
	*/

	#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;

	switch (instr & 0xfc0007ff) {
	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 - 4;
	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)) {
	/* generate an illegal instruction interrupt */
	kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
	return RESUME_GUEST;
	}
	if ((msr & MSR_PR) && !(vcpu->arch.fscr & FSCR_EBB)) {
	/* generate a facility unavailable interrupt */
	vcpu->arch.fscr = (vcpu->arch.fscr & ~(0xffull << 56)) \|
	((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 - 4;
	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;
	return RESUME_GUEST;

	case PPC_INST_TSR:
	/* 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)) {
	/* generate an illegal instruction interrupt */
	kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
	return RESUME_GUEST;
	}
	if (!(msr & MSR_TM)) {
	/* generate a facility unavailable interrupt */
	vcpu->arch.fscr = (vcpu->arch.fscr & ~(0xffull << 56)) \|
	((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;
	return RESUME_GUEST;

	case PPC_INST_TRECLAIM:
	/* check for TM disabled in the HFSCR or MSR */
	if (!(vcpu->arch.hfscr & HFSCR_TM)) {
	/* generate an illegal instruction interrupt */
	kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
	return RESUME_GUEST;
	}
	if (!(msr & MSR_TM)) {
	/* generate a facility unavailable interrupt */
	vcpu->arch.fscr = (vcpu->arch.fscr & ~(0xffull << 56)) \|
	((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;
	return RESUME_GUEST;

	case PPC_INST_TRECHKPT:
	/* 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)) {
	/* generate an illegal instruction interrupt */
	kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
	return RESUME_GUEST;
	}
	if (!(msr & MSR_TM)) {
	/* generate a facility unavailable interrupt */
	vcpu->arch.fscr = (vcpu->arch.fscr & ~(0xffull << 56)) \|
	((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;
	return RESUME_GUEST;
	}

	/* What should we do here? We didn't recognize the instruction */
	WARN_ON_ONCE(1);
	return RESUME_GUEST;
	}