From patchwork Thu Aug 3 02:21:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: zhaotianrui X-Patchwork-Id: 13339162 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57200C001DF for ; Thu, 3 Aug 2023 02:26:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233686AbjHCC0K (ORCPT ); Wed, 2 Aug 2023 22:26:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44496 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232085AbjHCCZX (ORCPT ); Wed, 2 Aug 2023 22:25:23 -0400 Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id CFE3A4681; Wed, 2 Aug 2023 19:22:48 -0700 (PDT) Received: from loongson.cn (unknown [10.2.5.185]) by gateway (Coremail) with SMTP id _____8DxRvFcD8tk62kPAA--.35930S3; Thu, 03 Aug 2023 10:22:20 +0800 (CST) Received: from localhost.localdomain (unknown [10.2.5.185]) by localhost.localdomain (Coremail) with SMTP id AQAAf8Cx_c4yD8tk8oNGAA--.51268S26; Thu, 03 Aug 2023 10:22:15 +0800 (CST) From: Tianrui Zhao To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Paolo Bonzini , Huacai Chen , WANG Xuerui , Greg Kroah-Hartman , loongarch@lists.linux.dev, Jens Axboe , Mark Brown , Alex Deucher , Oliver Upton , maobibo@loongson.cn, Xi Ruoyao , zhaotianrui@loongson.cn Subject: [PATCH v18 24/30] LoongArch: KVM: Implement handle mmio exception Date: Thu, 3 Aug 2023 10:21:32 +0800 Message-Id: <20230803022138.2736430-25-zhaotianrui@loongson.cn> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230803022138.2736430-1-zhaotianrui@loongson.cn> References: <20230803022138.2736430-1-zhaotianrui@loongson.cn> MIME-Version: 1.0 X-CM-TRANSID: AQAAf8Cx_c4yD8tk8oNGAA--.51268S26 X-CM-SenderInfo: p2kd03xldq233l6o00pqjv00gofq/ X-Coremail-Antispam: 1Uk129KBjDUn29KB7ZKAUJUUUUU529EdanIXcx71UUUUU7KY7 ZEXasCq-sGcSsGvfJ3UbIjqfuFe4nvWSU5nxnvy29KBjDU0xBIdaVrnUUvcSsGvfC2Kfnx nUUI43ZEXa7xR_UUUUUUUUU== Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Implement handle mmio exception, setting the mmio info into vcpu_run and return to user space to handle it. Reviewed-by: Bibo Mao Signed-off-by: Tianrui Zhao --- arch/loongarch/kvm/exit.c | 308 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 308 insertions(+) diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c index 04e4339cd78d..36a838607218 100644 --- a/arch/loongarch/kvm/exit.c +++ b/arch/loongarch/kvm/exit.c @@ -209,6 +209,265 @@ int _kvm_emu_idle(struct kvm_vcpu *vcpu) return EMULATE_DONE; } +int _kvm_emu_mmio_write(struct kvm_vcpu *vcpu, larch_inst inst) +{ + struct kvm_run *run = vcpu->run; + unsigned int rd, op8, opcode; + unsigned long rd_val = 0; + void *data = run->mmio.data; + unsigned long curr_pc; + int ret; + + /* + * Update PC and hold onto current PC in case there is + * an error and we want to rollback the PC + */ + curr_pc = vcpu->arch.pc; + update_pc(&vcpu->arch); + + op8 = (inst.word >> 24) & 0xff; + run->mmio.phys_addr = vcpu->arch.badv; + ret = EMULATE_DO_MMIO; + if (op8 < 0x28) { + /* stptrw/d process */ + rd = inst.reg2i14_format.rd; + opcode = inst.reg2i14_format.opcode; + + switch (opcode) { + case stptrd_op: + run->mmio.len = 8; + *(unsigned long *)data = vcpu->arch.gprs[rd]; + break; + case stptrw_op: + run->mmio.len = 4; + *(unsigned int *)data = vcpu->arch.gprs[rd]; + break; + default: + ret = EMULATE_FAIL; + break; + } + } else if (op8 < 0x30) { + /* st.b/h/w/d process */ + rd = inst.reg2i12_format.rd; + opcode = inst.reg2i12_format.opcode; + rd_val = vcpu->arch.gprs[rd]; + + switch (opcode) { + case std_op: + run->mmio.len = 8; + *(unsigned long *)data = rd_val; + break; + case stw_op: + run->mmio.len = 4; + *(unsigned int *)data = rd_val; + break; + case sth_op: + run->mmio.len = 2; + *(unsigned short *)data = rd_val; + break; + case stb_op: + run->mmio.len = 1; + *(unsigned char *)data = rd_val; + break; + default: + ret = EMULATE_FAIL; + break; + } + } else if (op8 == 0x38) { + /* stxb/h/w/d process */ + rd = inst.reg3_format.rd; + opcode = inst.reg3_format.opcode; + + switch (opcode) { + case stxb_op: + run->mmio.len = 1; + *(unsigned char *)data = vcpu->arch.gprs[rd]; + break; + case stxh_op: + run->mmio.len = 2; + *(unsigned short *)data = vcpu->arch.gprs[rd]; + break; + case stxw_op: + run->mmio.len = 4; + *(unsigned int *)data = vcpu->arch.gprs[rd]; + break; + case stxd_op: + run->mmio.len = 8; + *(unsigned long *)data = vcpu->arch.gprs[rd]; + break; + default: + ret = EMULATE_FAIL; + break; + } + } else + ret = EMULATE_FAIL; + + if (ret == EMULATE_DO_MMIO) { + run->mmio.is_write = 1; + vcpu->mmio_needed = 1; + vcpu->mmio_is_write = 1; + } else { + vcpu->arch.pc = curr_pc; + kvm_err("Write not supporded inst=0x%08x @%lx BadVaddr:%#lx\n", + inst.word, vcpu->arch.pc, vcpu->arch.badv); + kvm_arch_vcpu_dump_regs(vcpu); + /* Rollback PC if emulation was unsuccessful */ + } + + return ret; +} + +int _kvm_emu_mmio_read(struct kvm_vcpu *vcpu, larch_inst inst) +{ + unsigned int op8, opcode, rd; + struct kvm_run *run = vcpu->run; + int ret; + + run->mmio.phys_addr = vcpu->arch.badv; + vcpu->mmio_needed = 2; /* signed */ + op8 = (inst.word >> 24) & 0xff; + ret = EMULATE_DO_MMIO; + + if (op8 < 0x28) { + /* ldptr.w/d process */ + rd = inst.reg2i14_format.rd; + opcode = inst.reg2i14_format.opcode; + + switch (opcode) { + case ldptrd_op: + run->mmio.len = 8; + break; + case ldptrw_op: + run->mmio.len = 4; + break; + default: + break; + } + } else if (op8 < 0x2f) { + /* ld.b/h/w/d, ld.bu/hu/wu process */ + rd = inst.reg2i12_format.rd; + opcode = inst.reg2i12_format.opcode; + + switch (opcode) { + case ldd_op: + run->mmio.len = 8; + break; + case ldwu_op: + vcpu->mmio_needed = 1; /* unsigned */ + run->mmio.len = 4; + break; + case ldw_op: + run->mmio.len = 4; + break; + case ldhu_op: + vcpu->mmio_needed = 1; /* unsigned */ + run->mmio.len = 2; + break; + case ldh_op: + run->mmio.len = 2; + break; + case ldbu_op: + vcpu->mmio_needed = 1; /* unsigned */ + run->mmio.len = 1; + break; + case ldb_op: + run->mmio.len = 1; + break; + default: + ret = EMULATE_FAIL; + break; + } + } else if (op8 == 0x38) { + /* ldxb/h/w/d, ldxb/h/wu, ldgtb/h/w/d, ldleb/h/w/d process */ + rd = inst.reg3_format.rd; + opcode = inst.reg3_format.opcode; + + switch (opcode) { + case ldxb_op: + run->mmio.len = 1; + break; + case ldxbu_op: + run->mmio.len = 1; + vcpu->mmio_needed = 1; /* unsigned */ + break; + case ldxh_op: + run->mmio.len = 2; + break; + case ldxhu_op: + run->mmio.len = 2; + vcpu->mmio_needed = 1; /* unsigned */ + break; + case ldxw_op: + run->mmio.len = 4; + break; + case ldxwu_op: + run->mmio.len = 4; + vcpu->mmio_needed = 1; /* unsigned */ + break; + case ldxd_op: + run->mmio.len = 8; + break; + default: + ret = EMULATE_FAIL; + break; + } + } else + ret = EMULATE_FAIL; + + if (ret == EMULATE_DO_MMIO) { + /* Set for _kvm_complete_mmio_read use */ + vcpu->arch.io_gpr = rd; + run->mmio.is_write = 0; + vcpu->mmio_is_write = 0; + } else { + kvm_err("Load not supporded inst=0x%08x @%lx BadVaddr:%#lx\n", + inst.word, vcpu->arch.pc, vcpu->arch.badv); + kvm_arch_vcpu_dump_regs(vcpu); + vcpu->mmio_needed = 0; + } + return ret; +} + +int _kvm_complete_mmio_read(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + unsigned long *gpr = &vcpu->arch.gprs[vcpu->arch.io_gpr]; + enum emulation_result er = EMULATE_DONE; + + /* update with new PC */ + update_pc(&vcpu->arch); + switch (run->mmio.len) { + case 8: + *gpr = *(s64 *)run->mmio.data; + break; + case 4: + if (vcpu->mmio_needed == 2) + *gpr = *(int *)run->mmio.data; + else + *gpr = *(unsigned int *)run->mmio.data; + break; + case 2: + if (vcpu->mmio_needed == 2) + *gpr = *(short *) run->mmio.data; + else + *gpr = *(unsigned short *)run->mmio.data; + + break; + case 1: + if (vcpu->mmio_needed == 2) + *gpr = *(char *) run->mmio.data; + else + *gpr = *(unsigned char *) run->mmio.data; + break; + default: + kvm_err("Bad MMIO length: %d,addr is 0x%lx", + run->mmio.len, vcpu->arch.badv); + er = EMULATE_FAIL; + break; + } + + return er; +} + static int _kvm_trap_handle_gspr(struct kvm_vcpu *vcpu) { enum emulation_result er = EMULATE_DONE; @@ -323,3 +582,52 @@ static int _kvm_handle_gspr(struct kvm_vcpu *vcpu) } return ret; } + +static int _kvm_handle_mmu_fault(struct kvm_vcpu *vcpu, bool write) +{ + struct kvm_run *run = vcpu->run; + unsigned long badv = vcpu->arch.badv; + larch_inst inst; + enum emulation_result er = EMULATE_DONE; + int ret; + + ret = kvm_handle_mm_fault(vcpu, badv, write); + if (ret) { + /* Treat as MMIO */ + inst.word = vcpu->arch.badi; + if (write) { + er = _kvm_emu_mmio_write(vcpu, inst); + } else { + /* A code fetch fault doesn't count as an MMIO */ + if (kvm_is_ifetch_fault(&vcpu->arch)) { + kvm_err("%s ifetch error addr:%lx\n", __func__, badv); + run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + return RESUME_HOST; + } + + er = _kvm_emu_mmio_read(vcpu, inst); + } + } + + if (er == EMULATE_DONE) { + ret = RESUME_GUEST; + } else if (er == EMULATE_DO_MMIO) { + run->exit_reason = KVM_EXIT_MMIO; + ret = RESUME_HOST; + } else { + run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + ret = RESUME_HOST; + } + + return ret; +} + +static int _kvm_handle_write_fault(struct kvm_vcpu *vcpu) +{ + return _kvm_handle_mmu_fault(vcpu, true); +} + +static int _kvm_handle_read_fault(struct kvm_vcpu *vcpu) +{ + return _kvm_handle_mmu_fault(vcpu, false); +}