From:   Tianrui Zhao <zhaotianrui@loongson.cn>
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Huacai Chen <chenhuacai@kernel.org>,
        WANG Xuerui <kernel@xen0n.name>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        loongarch@lists.linux.dev, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, Jens Axboe <axboe@kernel.dk>,
        Mark Brown <broonie@kernel.org>,
        Alex Deucher <alexander.deucher@amd.com>,
        Oliver Upton <oliver.upton@linux.dev>, maobibo@loongson.cn,
        Xi Ruoyao <xry111@xry111.site>
Subject: [PATCH v4 26/29] LoongArch: KVM: Implement kvm exception vector
Date:   Tue, 21 Mar 2023 11:56:48 +0800
Message-Id: <20230321035651.598505-27-zhaotianrui@loongson.cn>
In-Reply-To: <20230321035651.598505-1-zhaotianrui@loongson.cn>
References: <20230321035651.598505-1-zhaotianrui@loongson.cn>
MIME-Version: 1.0
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Precedence: bulk

Implement kvm exception vector, using _kvm_fault_tables array to save
the handle function pointer and it is used when vcpu handle exit.

Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
---
 arch/loongarch/kvm/exit.c | 48 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c
index fc2152e09..1f95189f6 100644
--- a/arch/loongarch/kvm/exit.c
+++ b/arch/loongarch/kvm/exit.c
@@ -651,3 +651,51 @@ static int _kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu)
 	kvm_own_fpu(vcpu);
 	return RESUME_GUEST;
 }
+
+/*
+ * Loongarch KVM callback handling for not implemented guest exiting
+ */
+static int _kvm_fault_ni(struct kvm_vcpu *vcpu)
+{
+	unsigned long estat, badv;
+	unsigned int exccode, inst;
+
+	/*
+	 *  Fetch the instruction.
+	 */
+	badv = vcpu->arch.badv;
+	estat = vcpu->arch.host_estat;
+	exccode = (estat & CSR_ESTAT_EXC) >> CSR_ESTAT_EXC_SHIFT;
+	inst = vcpu->arch.badi;
+	kvm_err("Exccode: %d PC=%#lx inst=0x%08x BadVaddr=%#lx estat=%#llx\n",
+			exccode, vcpu->arch.pc, inst, badv, read_gcsr_estat());
+	kvm_arch_vcpu_dump_regs(vcpu);
+	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+
+	return RESUME_HOST;
+}
+
+static exit_handle_fn _kvm_fault_tables[EXCCODE_INT_START] = {
+	[EXCCODE_TLBL]		= _kvm_handle_read_fault,
+	[EXCCODE_TLBI]		= _kvm_handle_read_fault,
+	[EXCCODE_TLBNR]		= _kvm_handle_read_fault,
+	[EXCCODE_TLBNX]		= _kvm_handle_read_fault,
+	[EXCCODE_TLBS]		= _kvm_handle_write_fault,
+	[EXCCODE_TLBM]		= _kvm_handle_write_fault,
+	[EXCCODE_FPDIS]		= _kvm_handle_fpu_disabled,
+	[EXCCODE_GSPR]		= _kvm_handle_gspr,
+};
+
+int _kvm_handle_fault(struct kvm_vcpu *vcpu, int fault)
+{
+	return _kvm_fault_tables[fault](vcpu);
+}
+
+void _kvm_init_fault(void)
+{
+	int i;
+
+	for (i = 0; i < EXCCODE_INT_START; i++)
+		if (!_kvm_fault_tables[i])
+			_kvm_fault_tables[i] = _kvm_fault_ni;
+}
-- 
2.31.1