From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f71.google.com (mail-oi0-f71.google.com [209.85.218.71]) by kanga.kvack.org (Postfix) with ESMTP id 9FB226B0264 for ; Mon, 22 Aug 2016 19:24:05 -0400 (EDT) Received: by mail-oi0-f71.google.com with SMTP id i144so32031867oib.0 for ; Mon, 22 Aug 2016 16:24:05 -0700 (PDT) Received: from NAM02-BL2-obe.outbound.protection.outlook.com (mail-bl2nam02on0040.outbound.protection.outlook.com. [104.47.38.40]) by mx.google.com with ESMTPS id s187si132072ois.291.2016.08.22.16.24.04 for (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 22 Aug 2016 16:24:05 -0700 (PDT) Subject: [RFC PATCH v1 02/28] kvm: svm: Add kvm_fast_pio_in support From: Brijesh Singh Date: Mon, 22 Aug 2016 19:23:54 -0400 Message-ID: <147190823395.9523.16184607551630730040.stgit@brijesh-build-machine> In-Reply-To: <147190820782.9523.4967724730957229273.stgit@brijesh-build-machine> References: <147190820782.9523.4967724730957229273.stgit@brijesh-build-machine> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: simon.guinot@sequanux.org, linux-efi@vger.kernel.org, brijesh.singh@amd.com, kvm@vger.kernel.org, rkrcmar@redhat.com, matt@codeblueprint.co.uk, linus.walleij@linaro.org, linux-mm@kvack.org, paul.gortmaker@windriver.com, hpa@zytor.com, dan.j.williams@intel.com, aarcange@redhat.com, sfr@canb.auug.org.au, andriy.shevchenko@linux.intel.com, herbert@gondor.apana.org.au, bhe@redhat.com, xemul@parallels.com, joro@8bytes.org, x86@kernel.org, mingo@redhat.com, msalter@redhat.com, ross.zwisler@linux.intel.com, bp@suse.de, dyoung@redhat.com, thomas.lendacky@amd.com, jroedel@suse.de, keescook@chromium.org, toshi.kani@hpe.com, mathieu.desnoyers@efficios.com, devel@linuxdriverproject.org, tglx@linutronix.de, mchehab@kernel.org, iamjoonsoo.kim@lge.com, labbott@fedoraproject.org, tony.luck@intel.com, alexandre.bounine@idt.com, kuleshovmail@gmail.com, linux-kernel@vger.kernel.org, mcgrof@kernel.org, linux-crypto@vger.kernel.org, pbonzini@redhat.com, akpm@linux-foundation.org, davem@davemloft.net From: Tom Lendacky Update the I/O interception support to add the kvm_fast_pio_in function to speed up the in instruction similar to the out instruction. Signed-off-by: Tom Lendacky --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/svm.c | 5 +++-- arch/x86/kvm/x86.c | 43 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 47 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 3f05d36..c38f878 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1133,6 +1133,7 @@ int kvm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr); struct x86_emulate_ctxt; int kvm_fast_pio_out(struct kvm_vcpu *vcpu, int size, unsigned short port); +int kvm_fast_pio_in(struct kvm_vcpu *vcpu, int size, unsigned short port); void kvm_emulate_cpuid(struct kvm_vcpu *vcpu); int kvm_emulate_halt(struct kvm_vcpu *vcpu); int kvm_vcpu_halt(struct kvm_vcpu *vcpu); diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index d8b9c8c..fd5a9a8 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -2131,7 +2131,7 @@ static int io_interception(struct vcpu_svm *svm) ++svm->vcpu.stat.io_exits; string = (io_info & SVM_IOIO_STR_MASK) != 0; in = (io_info & SVM_IOIO_TYPE_MASK) != 0; - if (string || in) + if (string) return emulate_instruction(vcpu, 0) == EMULATE_DONE; port = io_info >> 16; @@ -2139,7 +2139,8 @@ static int io_interception(struct vcpu_svm *svm) svm->next_rip = svm->vmcb->control.exit_info_2; skip_emulated_instruction(&svm->vcpu); - return kvm_fast_pio_out(vcpu, size, port); + return in ? kvm_fast_pio_in(vcpu, size, port) + : kvm_fast_pio_out(vcpu, size, port); } static int nmi_interception(struct vcpu_svm *svm) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index d432894..78295b0 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5579,6 +5579,49 @@ int kvm_fast_pio_out(struct kvm_vcpu *vcpu, int size, unsigned short port) } EXPORT_SYMBOL_GPL(kvm_fast_pio_out); +static int complete_fast_pio_in(struct kvm_vcpu *vcpu) +{ + unsigned long val; + + /* We should only ever be called with arch.pio.count equal to 1 */ + BUG_ON(vcpu->arch.pio.count != 1); + + /* For size less than 4 we merge, else we zero extend */ + val = (vcpu->arch.pio.size < 4) ? kvm_register_read(vcpu, VCPU_REGS_RAX) + : 0; + + /* + * Since vcpu->arch.pio.count == 1 let emulator_pio_in_emulated perform + * the copy and tracing + */ + emulator_pio_in_emulated(&vcpu->arch.emulate_ctxt, vcpu->arch.pio.size, + vcpu->arch.pio.port, &val, 1); + kvm_register_write(vcpu, VCPU_REGS_RAX, val); + + return 1; +} + +int kvm_fast_pio_in(struct kvm_vcpu *vcpu, int size, unsigned short port) +{ + unsigned long val; + int ret; + + /* For size less than 4 we merge, else we zero extend */ + val = (size < 4) ? kvm_register_read(vcpu, VCPU_REGS_RAX) : 0; + + ret = emulator_pio_in_emulated(&vcpu->arch.emulate_ctxt, size, port, + &val, 1); + if (ret) { + kvm_register_write(vcpu, VCPU_REGS_RAX, val); + return ret; + } + + vcpu->arch.complete_userspace_io = complete_fast_pio_in; + + return 0; +} +EXPORT_SYMBOL_GPL(kvm_fast_pio_in); + static int kvmclock_cpu_down_prep(unsigned int cpu) { __this_cpu_write(cpu_tsc_khz, 0); -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org