Commit e880bd33 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

KVM: arm64: nv: Add trap forwarding for CNTHCTL_EL2 



Describe the CNTHCTL_EL2 register, and associate it with all the sysregs
it allows to trap.

Reviewed-by: default avatarEric Auger <eric.auger@redhat.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Reviewed-by: default avatarJing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20230815183903.2735724-19-maz@kernel.org
parent cb31632c

arch/arm64/kvm/emulate-nested.c

+49 −1
Original line number Diff line number Diff line
@@ -100,9 +100,11 @@ enum cgt_group_id { 


	/*

	 * Anything after this point requires a callback evaluating a

	 * complex trap condition. Hopefully we'll never need this...

	 * complex trap condition. Ugly stuff.

	 */

	__COMPLEX_CONDITIONS__,

	CGT_CNTHCTL_EL1PCTEN = __COMPLEX_CONDITIONS__,

	CGT_CNTHCTL_EL1PTEN,



	/* Must be last */

	__NR_CGT_GROUP_IDS__
@@ -369,10 +371,51 @@ static const enum cgt_group_id *coarse_control_combo[] = { 


typedef enum trap_behaviour (*complex_condition_check)(struct kvm_vcpu *);



/*

 * Warning, maximum confusion ahead.

 *

 * When E2H=0, CNTHCTL_EL2[1:0] are defined as EL1PCEN:EL1PCTEN

 * When E2H=1, CNTHCTL_EL2[11:10] are defined as EL1PTEN:EL1PCTEN

 *

 * Note the single letter difference? Yet, the bits have the same

 * function despite a different layout and a different name.

 *

 * We don't try to reconcile this mess. We just use the E2H=0 bits

 * to generate something that is in the E2H=1 format, and live with

 * it. You're welcome.

 */

static u64 get_sanitized_cnthctl(struct kvm_vcpu *vcpu)

{

	u64 val = __vcpu_sys_reg(vcpu, CNTHCTL_EL2);



	if (!vcpu_el2_e2h_is_set(vcpu))

		val = (val & (CNTHCTL_EL1PCEN | CNTHCTL_EL1PCTEN)) << 10;



	return val & ((CNTHCTL_EL1PCEN | CNTHCTL_EL1PCTEN) << 10);

}



static enum trap_behaviour check_cnthctl_el1pcten(struct kvm_vcpu *vcpu)

{

	if (get_sanitized_cnthctl(vcpu) & (CNTHCTL_EL1PCTEN << 10))

		return BEHAVE_HANDLE_LOCALLY;



	return BEHAVE_FORWARD_ANY;

}



static enum trap_behaviour check_cnthctl_el1pten(struct kvm_vcpu *vcpu)

{

	if (get_sanitized_cnthctl(vcpu) & (CNTHCTL_EL1PCEN << 10))

		return BEHAVE_HANDLE_LOCALLY;



	return BEHAVE_FORWARD_ANY;

}



#define CCC(id, fn)				\

	[id - __COMPLEX_CONDITIONS__] = fn



static const complex_condition_check ccc[] = {

	CCC(CGT_CNTHCTL_EL1PCTEN, check_cnthctl_el1pcten),

	CCC(CGT_CNTHCTL_EL1PTEN, check_cnthctl_el1pten),

};



/*
@@ -877,6 +920,11 @@ static const struct encoding_to_trap_config encoding_to_cgt[] __initconst = { 
	SR_TRAP(SYS_TRBPTR_EL1, 	CGT_MDCR_E2TB),

	SR_TRAP(SYS_TRBSR_EL1, 		CGT_MDCR_E2TB),

	SR_TRAP(SYS_TRBTRG_EL1,		CGT_MDCR_E2TB),

	SR_TRAP(SYS_CNTP_TVAL_EL0,	CGT_CNTHCTL_EL1PTEN),

	SR_TRAP(SYS_CNTP_CVAL_EL0,	CGT_CNTHCTL_EL1PTEN),

	SR_TRAP(SYS_CNTP_CTL_EL0,	CGT_CNTHCTL_EL1PTEN),

	SR_TRAP(SYS_CNTPCT_EL0,		CGT_CNTHCTL_EL1PCTEN),

	SR_TRAP(SYS_CNTPCTSS_EL0,	CGT_CNTHCTL_EL1PCTEN),

};



static DEFINE_XARRAY(sr_forward_xa);