Commit c046de82 authored by Clément Léger's avatar Clément Léger Committed by Anup Patel
Browse files

RISC-V: KVM: add SBI extension reset callback 



Currently, only the STA extension needed a reset function but that's
going to be the case for FWFT as well. Add a reset callback that can
be implemented by SBI extensions.

Signed-off-by: default avatarClément Léger <cleger@rivosinc.com>
Reviewed-by: default avatarAndrew Jones <ajones@ventanamicro.com>
Reviewed-by: default avatarAtish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20250523101932.1594077-13-cleger@rivosinc.com


Signed-off-by: default avatarAnup Patel <anup@brainfault.org>
parent cf648c40

arch/riscv/include/asm/kvm_host.h

+0 −1
Original line number Diff line number Diff line
@@ -415,7 +415,6 @@ void __kvm_riscv_vcpu_power_on(struct kvm_vcpu *vcpu); 
void kvm_riscv_vcpu_power_on(struct kvm_vcpu *vcpu);

bool kvm_riscv_vcpu_stopped(struct kvm_vcpu *vcpu);



void kvm_riscv_vcpu_sbi_sta_reset(struct kvm_vcpu *vcpu);

void kvm_riscv_vcpu_record_steal_time(struct kvm_vcpu *vcpu);



#endif /* __RISCV_KVM_HOST_H__ */

arch/riscv/include/asm/kvm_vcpu_sbi.h

+3 −0
Original line number Diff line number Diff line
@@ -57,6 +57,8 @@ struct kvm_vcpu_sbi_extension { 
	 */

	int (*init)(struct kvm_vcpu *vcpu);

	void (*deinit)(struct kvm_vcpu *vcpu);



	void (*reset)(struct kvm_vcpu *vcpu);

};



void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run);
@@ -81,6 +83,7 @@ bool riscv_vcpu_supports_sbi_ext(struct kvm_vcpu *vcpu, int idx); 
int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run);

void kvm_riscv_vcpu_sbi_init(struct kvm_vcpu *vcpu);

void kvm_riscv_vcpu_sbi_deinit(struct kvm_vcpu *vcpu);

void kvm_riscv_vcpu_sbi_reset(struct kvm_vcpu *vcpu);



int kvm_riscv_vcpu_get_reg_sbi_sta(struct kvm_vcpu *vcpu, unsigned long reg_num,

				   unsigned long *reg_val);

arch/riscv/kvm/vcpu.c

+1 −1
Original line number Diff line number Diff line
@@ -111,7 +111,7 @@ static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu, bool kvm_sbi_reset) 
	vcpu->arch.hfence_tail = 0;

	memset(vcpu->arch.hfence_queue, 0, sizeof(vcpu->arch.hfence_queue));



	kvm_riscv_vcpu_sbi_sta_reset(vcpu);

	kvm_riscv_vcpu_sbi_reset(vcpu);



	/* Reset the guest CSRs for hotplug usecase */

	if (loaded)

arch/riscv/kvm/vcpu_sbi.c

+23 −0
Original line number Diff line number Diff line
@@ -564,3 +564,26 @@ void kvm_riscv_vcpu_sbi_deinit(struct kvm_vcpu *vcpu) 
		ext->deinit(vcpu);

	}

}



void kvm_riscv_vcpu_sbi_reset(struct kvm_vcpu *vcpu)

{

	struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context;

	const struct kvm_riscv_sbi_extension_entry *entry;

	const struct kvm_vcpu_sbi_extension *ext;

	int idx, i;



	for (i = 0; i < ARRAY_SIZE(sbi_ext); i++) {

		entry = &sbi_ext[i];

		ext = entry->ext_ptr;

		idx = entry->ext_idx;



		if (idx < 0 || idx >= ARRAY_SIZE(scontext->ext_status))

			continue;



		if (scontext->ext_status[idx] != KVM_RISCV_SBI_EXT_STATUS_ENABLED ||

		    !ext->reset)

			continue;



		ext->reset(vcpu);

	}

}

arch/riscv/kvm/vcpu_sbi_sta.c

+2 −1
Original line number Diff line number Diff line
@@ -16,7 +16,7 @@ 
#include <asm/sbi.h>

#include <asm/uaccess.h>



void kvm_riscv_vcpu_sbi_sta_reset(struct kvm_vcpu *vcpu)

static void kvm_riscv_vcpu_sbi_sta_reset(struct kvm_vcpu *vcpu)

{

	vcpu->arch.sta.shmem = INVALID_GPA;

	vcpu->arch.sta.last_steal = 0;
@@ -156,6 +156,7 @@ const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_sta = { 
	.extid_end = SBI_EXT_STA,

	.handler = kvm_sbi_ext_sta_handler,

	.probe = kvm_sbi_ext_sta_probe,

	.reset = kvm_riscv_vcpu_sbi_sta_reset,

};



int kvm_riscv_vcpu_get_reg_sbi_sta(struct kvm_vcpu *vcpu,