Commit b22216e1 authored by Raghavendra Rao Ananta's avatar Raghavendra Rao Ananta Committed by Marc Zyngier
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KVM: arm64: Add vendor hypervisor firmware register 



Introduce the firmware register to hold the vendor specific
hypervisor service calls (owner value 6) as a bitmap. The
bitmap represents the features that'll be enabled for the
guest, as configured by the user-space. Currently, this
includes support for KVM-vendor features along with
reading the UID, represented by bit-0, and Precision Time
Protocol (PTP), represented by bit-1.

Signed-off-by: default avatarRaghavendra Rao Ananta <rananta@google.com>
Reviewed-by: default avatarGavin Shan <gshan@redhat.com>
[maz: tidy-up bitmap values]
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220502233853.1233742-5-rananta@google.com
parent 428fd678

arch/arm64/include/asm/kvm_host.h

+2 −0
Original line number Diff line number Diff line
@@ -106,10 +106,12 @@ struct kvm_arch_memory_slot { 
 *

 * @std_bmap: Bitmap of standard secure service calls

 * @std_hyp_bmap: Bitmap of standard hypervisor service calls

 * @vendor_hyp_bmap: Bitmap of vendor specific hypervisor service calls

 */

struct kvm_smccc_features {

	unsigned long std_bmap;

	unsigned long std_hyp_bmap;

	unsigned long vendor_hyp_bmap;

};



struct kvm_arch {

arch/arm64/include/uapi/asm/kvm.h

+8 −0
Original line number Diff line number Diff line
@@ -352,6 +352,14 @@ enum { 
	KVM_REG_ARM_STD_HYP_BMAP_BIT_COUNT,

};



#define KVM_REG_ARM_VENDOR_HYP_BMAP		KVM_REG_ARM_FW_FEAT_BMAP_REG(2)



enum {

	KVM_REG_ARM_VENDOR_HYP_BIT_FUNC_FEAT	= 0,

	KVM_REG_ARM_VENDOR_HYP_BIT_PTP		= 1,

	KVM_REG_ARM_VENDOR_HYP_BMAP_BIT_COUNT,

};



/* Device Control API: ARM VGIC */

#define KVM_DEV_ARM_VGIC_GRP_ADDR	0

#define KVM_DEV_ARM_VGIC_GRP_DIST_REGS	1

arch/arm64/kvm/hypercalls.c

+20 −5
Original line number Diff line number Diff line
@@ -13,6 +13,8 @@ 
	GENMASK(KVM_REG_ARM_STD_BMAP_BIT_COUNT - 1, 0)

#define KVM_ARM_SMCCC_STD_HYP_FEATURES				\

	GENMASK(KVM_REG_ARM_STD_HYP_BMAP_BIT_COUNT - 1, 0)

#define KVM_ARM_SMCCC_VENDOR_HYP_FEATURES			\

	GENMASK(KVM_REG_ARM_VENDOR_HYP_BMAP_BIT_COUNT - 1, 0)



static void kvm_ptp_get_time(struct kvm_vcpu *vcpu, u64 *val)

{
@@ -73,9 +75,6 @@ static bool kvm_hvc_call_default_allowed(u32 func_id) 
	 */

	case ARM_SMCCC_VERSION_FUNC_ID:

	case ARM_SMCCC_ARCH_FEATURES_FUNC_ID:

	case ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID:

	case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID:

	case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID:

		return true;

	default:

		/* PSCI 0.2 and up is in the 0:0x1f range */
@@ -110,6 +109,13 @@ static bool kvm_hvc_call_allowed(struct kvm_vcpu *vcpu, u32 func_id) 
	case ARM_SMCCC_HV_PV_TIME_ST:

		return test_bit(KVM_REG_ARM_STD_HYP_BIT_PV_TIME,

				&smccc_feat->std_hyp_bmap);

	case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID:

	case ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID:

		return test_bit(KVM_REG_ARM_VENDOR_HYP_BIT_FUNC_FEAT,

				&smccc_feat->vendor_hyp_bmap);

	case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID:

		return test_bit(KVM_REG_ARM_VENDOR_HYP_BIT_PTP,

				&smccc_feat->vendor_hyp_bmap);

	default:

		return kvm_hvc_call_default_allowed(func_id);

	}
@@ -202,8 +208,7 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) 
		val[3] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_3;

		break;

	case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID:

		val[0] = BIT(ARM_SMCCC_KVM_FUNC_FEATURES);

		val[0] |= BIT(ARM_SMCCC_KVM_FUNC_PTP);

		val[0] = smccc_feat->vendor_hyp_bmap;

		break;

	case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID:

		kvm_ptp_get_time(vcpu, val);
@@ -230,6 +235,7 @@ static const u64 kvm_arm_fw_reg_ids[] = { 
	KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3,

	KVM_REG_ARM_STD_BMAP,

	KVM_REG_ARM_STD_HYP_BMAP,

	KVM_REG_ARM_VENDOR_HYP_BMAP,

};



void kvm_arm_init_hypercalls(struct kvm *kvm)
@@ -238,6 +244,7 @@ void kvm_arm_init_hypercalls(struct kvm *kvm) 


	smccc_feat->std_bmap = KVM_ARM_SMCCC_STD_FEATURES;

	smccc_feat->std_hyp_bmap = KVM_ARM_SMCCC_STD_HYP_FEATURES;

	smccc_feat->vendor_hyp_bmap = KVM_ARM_SMCCC_VENDOR_HYP_FEATURES;

}



int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu)
@@ -329,6 +336,9 @@ int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) 
	case KVM_REG_ARM_STD_HYP_BMAP:

		val = READ_ONCE(smccc_feat->std_hyp_bmap);

		break;

	case KVM_REG_ARM_VENDOR_HYP_BMAP:

		val = READ_ONCE(smccc_feat->vendor_hyp_bmap);

		break;

	default:

		return -ENOENT;

	}
@@ -355,6 +365,10 @@ static int kvm_arm_set_fw_reg_bmap(struct kvm_vcpu *vcpu, u64 reg_id, u64 val) 
		fw_reg_bmap = &smccc_feat->std_hyp_bmap;

		fw_reg_features = KVM_ARM_SMCCC_STD_HYP_FEATURES;

		break;

	case KVM_REG_ARM_VENDOR_HYP_BMAP:

		fw_reg_bmap = &smccc_feat->vendor_hyp_bmap;

		fw_reg_features = KVM_ARM_SMCCC_VENDOR_HYP_FEATURES;

		break;

	default:

		return -ENOENT;

	}
@@ -456,6 +470,7 @@ int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) 
		return 0;

	case KVM_REG_ARM_STD_BMAP:

	case KVM_REG_ARM_STD_HYP_BMAP:

	case KVM_REG_ARM_VENDOR_HYP_BMAP:

		return kvm_arm_set_fw_reg_bmap(vcpu, reg->id, val);

	default:

		return -ENOENT;