From nobody Tue Sep 9 21:55:03 2025 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 18BECC64ED6 for ; Tue, 28 Feb 2023 07:02:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231158AbjB1HCb (ORCPT ); Tue, 28 Feb 2023 02:02:31 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47988 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230224AbjB1HBK (ORCPT ); Tue, 28 Feb 2023 02:01:10 -0500 Received: from loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id B852A29E33; Mon, 27 Feb 2023 23:01:07 -0800 (PST) Received: from loongson.cn (unknown [10.2.5.185]) by gateway (Coremail) with SMTP id _____8DxJYyypv1jLmEGAA--.6457S3; Tue, 28 Feb 2023 15:01:06 +0800 (CST) Received: from localhost.localdomain (unknown [10.2.5.185]) by localhost.localdomain (Coremail) with SMTP id AQAAf8Bxc+Wppv1jPG9AAA--.15462S26; Tue, 28 Feb 2023 15:01:05 +0800 (CST) From: Tianrui Zhao To: Paolo Bonzini Cc: Huacai Chen , WANG Xuerui , Greg Kroah-Hartman , loongarch@lists.linux.dev, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Jens Axboe , Mark Brown , Alex Deucher , Oliver Upton , maobibo@loongson.cn, Xi Ruoyao Subject: [PATCH v3 24/29] LoongArch: KVM: Implement handle mmio exception Date: Tue, 28 Feb 2023 15:00:51 +0800 Message-Id: <20230228070057.3687180-25-zhaotianrui@loongson.cn> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230228070057.3687180-1-zhaotianrui@loongson.cn> References: <20230228070057.3687180-1-zhaotianrui@loongson.cn> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: AQAAf8Bxc+Wppv1jPG9AAA--.15462S26 X-CM-SenderInfo: p2kd03xldq233l6o00pqjv00gofq/ X-Coremail-Antispam: 1Uk129KBjvJXoW3JFWfZF48Cr4Utry5Kr1kAFb_yoW3GF1fpr WUC34jvrsaqryYy3srKrs5Xr1a9F48GrsrJrZ7t39Fgr17tFy5Ar4v9rW2vFW3CrWF9a1x Z3Z3JF47uF1UAa7anT9S1TB71UUUUjJqnTZGkaVYY2UrUUUUj1kv1TuYvTs0mT0YCTnIWj qI5I8CrVACY4xI64kE6c02F40Ex7xfYxn0WfASr-VFAUDa7-sFnT9fnUUIcSsGvfJTRUUU b4AFc2x0x2IEx4CE42xK8VAvwI8IcIk0rVWrJVCq3wA2ocxC64kIII0Yj41l84x0c7CEw4 AK67xGY2AK021l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xvwVC0I7IYx2IY6xkF 7I0E14v26r4UJVWxJr1l84ACjcxK6I8E87Iv67AKxVWxJr0_GcWl84ACjcxK6I8E87Iv6x kF7I0E14v26F4UJVW0owAaw2AFwI0_JF0_Jw1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAq jxCEc2xF0cIa020Ex4CE44I27wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E74AGY7Cv6c x26rWlOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JMxkF7I0En4kS14v26r12 6r1DMxAIw28IcxkI7VAKI48JMxAIw28IcVCjz48v1sIEY20_WwCFx2IqxVCFs4IE7xkEbV WUJVW8JwCFI7km07C267AKxVWUAVWUtwC20s026c02F40E14v26r1j6r18MI8I3I0E7480 Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7 IYx2IY67AKxVWDJVCq3wCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJwCI42IY6xAI w20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Gr1j6F4UJwCI42IY6I8E87Iv6x kF7I0E14v26r4UJVWxJrUvcSsGvfC2KfnxnUUI43ZEXa7xRiTKZJUUUUU== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Implement handle mmio exception, setting the mmio info into vcpu_run and return to user space to handle it. 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 97b90b04d641..85e2523dad33 100644 --- a/arch/loongarch/kvm/exit.c +++ b/arch/loongarch/kvm/exit.c @@ -204,6 +204,265 @@ int _kvm_emu_idle(struct kvm_vcpu *vcpu) return EMULATE_DONE; } =20 +int _kvm_emu_mmio_write(struct kvm_vcpu *vcpu, larch_inst inst) +{ + struct kvm_run *run =3D vcpu->run; + unsigned int rd, op8, opcode; + unsigned long rd_val =3D 0; + void *data =3D 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 =3D vcpu->arch.pc; + update_pc(&vcpu->arch); + + op8 =3D (inst.word >> 24) & 0xff; + run->mmio.phys_addr =3D vcpu->arch.badv; + ret =3D EMULATE_DO_MMIO; + if (op8 < 0x28) { + /* stptrw/d process */ + rd =3D inst.reg2i14_format.rd; + opcode =3D inst.reg2i14_format.opcode; + + switch (opcode) { + case stptrd_op: + run->mmio.len =3D 8; + *(unsigned long *)data =3D vcpu->arch.gprs[rd]; + break; + case stptrw_op: + run->mmio.len =3D 4; + *(unsigned int *)data =3D vcpu->arch.gprs[rd]; + break; + default: + ret =3D EMULATE_FAIL; + break; + } + } else if (op8 < 0x30) { + /* st.b/h/w/d process */ + rd =3D inst.reg2i12_format.rd; + opcode =3D inst.reg2i12_format.opcode; + rd_val =3D vcpu->arch.gprs[rd]; + + switch (opcode) { + case std_op: + run->mmio.len =3D 8; + *(unsigned long *)data =3D rd_val; + break; + case stw_op: + run->mmio.len =3D 4; + *(unsigned int *)data =3D rd_val; + break; + case sth_op: + run->mmio.len =3D 2; + *(unsigned short *)data =3D rd_val; + break; + case stb_op: + run->mmio.len =3D 1; + *(unsigned char *)data =3D rd_val; + break; + default: + ret =3D EMULATE_FAIL; + break; + } + } else if (op8 =3D=3D 0x38) { + /* stxb/h/w/d process */ + rd =3D inst.reg3_format.rd; + opcode =3D inst.reg3_format.opcode; + + switch (opcode) { + case stxb_op: + run->mmio.len =3D 1; + *(unsigned char *)data =3D vcpu->arch.gprs[rd]; + break; + case stxh_op: + run->mmio.len =3D 2; + *(unsigned short *)data =3D vcpu->arch.gprs[rd]; + break; + case stxw_op: + run->mmio.len =3D 4; + *(unsigned int *)data =3D vcpu->arch.gprs[rd]; + break; + case stxd_op: + run->mmio.len =3D 8; + *(unsigned long *)data =3D vcpu->arch.gprs[rd]; + break; + default: + ret =3D EMULATE_FAIL; + break; + } + } else + ret =3D EMULATE_FAIL; + + if (ret =3D=3D EMULATE_DO_MMIO) { + run->mmio.is_write =3D 1; + vcpu->mmio_needed =3D 1; + vcpu->mmio_is_write =3D 1; + } else { + vcpu->arch.pc =3D curr_pc; + kvm_err("Write not supporded inst=3D0x%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 =3D vcpu->run; + int ret; + + run->mmio.phys_addr =3D vcpu->arch.badv; + vcpu->mmio_needed =3D 2; /* signed */ + op8 =3D (inst.word >> 24) & 0xff; + ret =3D EMULATE_DO_MMIO; + + if (op8 < 0x28) { + /* ldptr.w/d process */ + rd =3D inst.reg2i14_format.rd; + opcode =3D inst.reg2i14_format.opcode; + + switch (opcode) { + case ldptrd_op: + run->mmio.len =3D 8; + break; + case ldptrw_op: + run->mmio.len =3D 4; + break; + default: + break; + } + } else if (op8 < 0x2f) { + /* ld.b/h/w/d, ld.bu/hu/wu process */ + rd =3D inst.reg2i12_format.rd; + opcode =3D inst.reg2i12_format.opcode; + + switch (opcode) { + case ldd_op: + run->mmio.len =3D 8; + break; + case ldwu_op: + vcpu->mmio_needed =3D 1; /* unsigned */ + run->mmio.len =3D 4; + break; + case ldw_op: + run->mmio.len =3D 4; + break; + case ldhu_op: + vcpu->mmio_needed =3D 1; /* unsigned */ + run->mmio.len =3D 2; + break; + case ldh_op: + run->mmio.len =3D 2; + break; + case ldbu_op: + vcpu->mmio_needed =3D 1; /* unsigned */ + run->mmio.len =3D 1; + break; + case ldb_op: + run->mmio.len =3D 1; + break; + default: + ret =3D EMULATE_FAIL; + break; + } + } else if (op8 =3D=3D 0x38) { + /* ldxb/h/w/d, ldxb/h/wu, ldgtb/h/w/d, ldleb/h/w/d process */ + rd =3D inst.reg3_format.rd; + opcode =3D inst.reg3_format.opcode; + + switch (opcode) { + case ldxb_op: + run->mmio.len =3D 1; + break; + case ldxbu_op: + run->mmio.len =3D 1; + vcpu->mmio_needed =3D 1; /* unsigned */ + break; + case ldxh_op: + run->mmio.len =3D 2; + break; + case ldxhu_op: + run->mmio.len =3D 2; + vcpu->mmio_needed =3D 1; /* unsigned */ + break; + case ldxw_op: + run->mmio.len =3D 4; + break; + case ldxwu_op: + run->mmio.len =3D 4; + vcpu->mmio_needed =3D 1; /* unsigned */ + break; + case ldxd_op: + run->mmio.len =3D 8; + break; + default: + ret =3D EMULATE_FAIL; + break; + } + } else + ret =3D EMULATE_FAIL; + + if (ret =3D=3D EMULATE_DO_MMIO) { + /* Set for _kvm_complete_mmio_read use */ + vcpu->arch.io_gpr =3D rd; + run->mmio.is_write =3D 0; + vcpu->mmio_is_write =3D 0; + } else { + kvm_err("Load not supporded inst=3D0x%08x @%lx BadVaddr:%#lx\n", + inst.word, vcpu->arch.pc, vcpu->arch.badv); + kvm_arch_vcpu_dump_regs(vcpu); + vcpu->mmio_needed =3D 0; + } + return ret; +} + +int _kvm_complete_mmio_read(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + unsigned long *gpr =3D &vcpu->arch.gprs[vcpu->arch.io_gpr]; + enum emulation_result er =3D EMULATE_DONE; + + /* update with new PC */ + update_pc(&vcpu->arch); + switch (run->mmio.len) { + case 8: + *gpr =3D *(s64 *)run->mmio.data; + break; + case 4: + if (vcpu->mmio_needed =3D=3D 2) + *gpr =3D *(int *)run->mmio.data; + else + *gpr =3D *(unsigned int *)run->mmio.data; + break; + case 2: + if (vcpu->mmio_needed =3D=3D 2) + *gpr =3D *(short *) run->mmio.data; + else + *gpr =3D *(unsigned short *)run->mmio.data; + + break; + case 1: + if (vcpu->mmio_needed =3D=3D 2) + *gpr =3D *(char *) run->mmio.data; + else + *gpr =3D *(unsigned char *) run->mmio.data; + break; + default: + kvm_err("Bad MMIO length: %d,addr is 0x%lx", + run->mmio.len, vcpu->arch.badv); + er =3D EMULATE_FAIL; + break; + } + + return er; +} + static int _kvm_trap_handle_gspr(struct kvm_vcpu *vcpu) { enum emulation_result er =3D EMULATE_DONE; @@ -318,3 +577,52 @@ 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 =3D vcpu->run; + unsigned long badv =3D vcpu->arch.badv; + larch_inst inst; + enum emulation_result er =3D EMULATE_DONE; + int ret; + + ret =3D kvm_handle_mm_fault(vcpu, badv, write); + if (ret) { + /* Treat as MMIO */ + inst.word =3D vcpu->arch.badi; + if (write) { + er =3D _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 =3D KVM_EXIT_INTERNAL_ERROR; + return RESUME_HOST; + } + + er =3D _kvm_emu_mmio_read(vcpu, inst); + } + } + + if (er =3D=3D EMULATE_DONE) { + ret =3D RESUME_GUEST; + } else if (er =3D=3D EMULATE_DO_MMIO) { + run->exit_reason =3D KVM_EXIT_MMIO; + ret =3D RESUME_HOST; + } else { + run->exit_reason =3D KVM_EXIT_INTERNAL_ERROR; + ret =3D 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); +} --=20 2.31.1