From patchwork Thu Nov 18 08:39:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Atish Kumar Patra X-Patchwork-Id: 12626283 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 389D2C433F5 for ; Thu, 18 Nov 2021 08:41:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 140FF61B3E for ; Thu, 18 Nov 2021 08:41:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244735AbhKRInO (ORCPT ); Thu, 18 Nov 2021 03:43:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49066 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244714AbhKRInG (ORCPT ); Thu, 18 Nov 2021 03:43:06 -0500 Received: from mail-oo1-xc2f.google.com (mail-oo1-xc2f.google.com [IPv6:2607:f8b0:4864:20::c2f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 606D7C061767 for ; Thu, 18 Nov 2021 00:40:06 -0800 (PST) Received: by mail-oo1-xc2f.google.com with SMTP id v30-20020a4a315e000000b002c52d555875so2142780oog.12 for ; Thu, 18 Nov 2021 00:40:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=j5rnL+4PBNac93hwYSim5xX6bG0qtM8Vy6bQe7kCJ8s=; b=Ma/tYlfvaTz8KqSm3kIDsGZo8cY9c64c46DbdIkz+WHUBPknCgYV4fEI8d0SOmWPQt 2wtobzEcrTETfKNhuXGVgWlK5RcPACfBdTTs4sAj/m97kBMHtsyakKXHwOh43lfC3D+M +Uz99k+gOIC3SEV7fXixA0ILCQTmEav9b/RQ/sWb2O9IP6vVsOxO76RwW6cq7fTTTCyP 5YnLJxA83vYLs2y5WfDGbHRsuL9C7qAMYrxAl0lxnZxb2OXgoU2FUsVbt6b33Z20hWEI S7pLx8ssXz+rSSqWd7FjnuNO/ak1/3/gD2VQqy4/qqEKJtoMd1fSwIkEOYpDphKThZtV Itng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=j5rnL+4PBNac93hwYSim5xX6bG0qtM8Vy6bQe7kCJ8s=; b=XPT2bHOVkHFLIThadBTwooFIqnlvA5L5wnJ1HoAPvnXKz1hJ1B8dVR9Eypqjyv86D8 1jsj5yU7NWfbjaXgV0NdA9/HOPxRrOxUB3nmclz2oFLrkGlIm0a2PyF1jHVC8GJLBsYn izZisZ9UFZVFR8HCMESo8+r+yWAmVpZWCF+1RQIR9H02PIJfwkN1fL5ss+bT8YmqXiC/ NhJLv78ruxWEOZQmg9mcl7o1YF3TQyojIFT3fKRwdWD5bOJ86O2RSTDR+EJnixUC2g6r OCOv7TghOs9pDGA4rhGoAlvZns3opZDMSdlBR1qdU4fOY4cLkT0V+1TAPLS2ect9Iz9o 48QA== X-Gm-Message-State: AOAM530KO5Wdm0jUw0hc2Xbok5LKOcK3TnrCLwakEh84vSSxXa7wN6lA COHu80kQf1YBGDAXhdMalgXsXA== X-Google-Smtp-Source: ABdhPJwLk+wjI9jaszIsjbCnufZRlUzurBZILMJYvuF6vUi+X56nO16gSQvofgvDcQazHSwGimvY9A== X-Received: by 2002:a4a:7559:: with SMTP id g25mr9158757oof.54.1637224805586; Thu, 18 Nov 2021 00:40:05 -0800 (PST) Received: from fedora.. (99-13-229-45.lightspeed.snjsca.sbcglobal.net. [99.13.229.45]) by smtp.gmail.com with ESMTPSA id p14sm422100oov.0.2021.11.18.00.40.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Nov 2021 00:40:05 -0800 (PST) From: Atish Patra To: linux-kernel@vger.kernel.org Cc: Atish Patra , Anup Patel , Atish Patra , Albert Ou , Heinrich Schuchardt , Kefeng Wang , kvm-riscv@lists.infradead.org, kvm@vger.kernel.org, linux-riscv@lists.infradead.org, Palmer Dabbelt , Paul Walmsley Subject: [PATCH v5 1/5] RISC-V: KVM: Mark the existing SBI implementation as v01 Date: Thu, 18 Nov 2021 00:39:08 -0800 Message-Id: <20211118083912.981995-2-atishp@rivosinc.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211118083912.981995-1-atishp@rivosinc.com> References: <20211118083912.981995-1-atishp@rivosinc.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Atish Patra The existing SBI specification impelementation follows v0.1 specification. The latest specification allows more scalability and performance improvements. Rename the existing implementation as v01 and provide a way to allow future extensions. Reviewed-by: Anup Patel Signed-off-by: Atish Patra Signed-off-by: Atish Patra --- arch/riscv/include/asm/kvm_vcpu_sbi.h | 29 +++++ arch/riscv/kvm/vcpu_sbi.c | 149 ++++++++++++++++++++------ 2 files changed, 145 insertions(+), 33 deletions(-) create mode 100644 arch/riscv/include/asm/kvm_vcpu_sbi.h diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h new file mode 100644 index 000000000000..1a4cb0db2d0b --- /dev/null +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h @@ -0,0 +1,29 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/** + * Copyright (c) 2021 Western Digital Corporation or its affiliates. + * + * Authors: + * Atish Patra + */ + +#ifndef __RISCV_KVM_VCPU_SBI_H__ +#define __RISCV_KVM_VCPU_SBI_H__ + +#define KVM_SBI_VERSION_MAJOR 0 +#define KVM_SBI_VERSION_MINOR 2 + +struct kvm_vcpu_sbi_extension { + unsigned long extid_start; + unsigned long extid_end; + /** + * SBI extension handler. It can be defined for a given extension or group of + * extension. But it should always return linux error codes rather than SBI + * specific error codes. + */ + int (*handler)(struct kvm_vcpu *vcpu, struct kvm_run *run, + unsigned long *out_val, struct kvm_cpu_trap *utrap, + bool *exit); +}; + +const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(unsigned long extid); +#endif /* __RISCV_KVM_VCPU_SBI_H__ */ diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c index eb3c045edf11..32376906ff20 100644 --- a/arch/riscv/kvm/vcpu_sbi.c +++ b/arch/riscv/kvm/vcpu_sbi.c @@ -1,5 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 -/** +/* * Copyright (c) 2019 Western Digital Corporation or its affiliates. * * Authors: @@ -12,9 +12,25 @@ #include #include #include +#include -#define SBI_VERSION_MAJOR 0 -#define SBI_VERSION_MINOR 1 +static int kvm_linux_err_map_sbi(int err) +{ + switch (err) { + case 0: + return SBI_SUCCESS; + case -EPERM: + return SBI_ERR_DENIED; + case -EINVAL: + return SBI_ERR_INVALID_PARAM; + case -EFAULT: + return SBI_ERR_INVALID_ADDRESS; + case -EOPNOTSUPP: + return SBI_ERR_NOT_SUPPORTED; + default: + return SBI_ERR_FAILURE; + }; +} static void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run) @@ -72,21 +88,19 @@ static void kvm_sbi_system_shutdown(struct kvm_vcpu *vcpu, run->exit_reason = KVM_EXIT_SYSTEM_EVENT; } -int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) +static int kvm_sbi_ext_v01_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, + unsigned long *out_val, + struct kvm_cpu_trap *utrap, + bool *exit) { ulong hmask; - int i, ret = 1; + int i, ret = 0; u64 next_cycle; struct kvm_vcpu *rvcpu; - bool next_sepc = true; struct cpumask cm, hm; struct kvm *kvm = vcpu->kvm; - struct kvm_cpu_trap utrap = { 0 }; struct kvm_cpu_context *cp = &vcpu->arch.guest_context; - if (!cp) - return -EINVAL; - switch (cp->a7) { case SBI_EXT_0_1_CONSOLE_GETCHAR: case SBI_EXT_0_1_CONSOLE_PUTCHAR: @@ -95,8 +109,7 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) * handled in kernel so we forward these to user-space */ kvm_riscv_vcpu_sbi_forward(vcpu, run); - next_sepc = false; - ret = 0; + *exit = true; break; case SBI_EXT_0_1_SET_TIMER: #if __riscv_xlen == 32 @@ -104,47 +117,42 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) #else next_cycle = (u64)cp->a0; #endif - kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle); + ret = kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle); break; case SBI_EXT_0_1_CLEAR_IPI: - kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_SOFT); + ret = kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_SOFT); break; case SBI_EXT_0_1_SEND_IPI: if (cp->a0) hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0, - &utrap); + utrap); else hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; - if (utrap.scause) { - utrap.sepc = cp->sepc; - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); - next_sepc = false; + if (utrap->scause) break; - } + for_each_set_bit(i, &hmask, BITS_PER_LONG) { rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i); - kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT); + ret = kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT); + if (ret < 0) + break; } break; case SBI_EXT_0_1_SHUTDOWN: kvm_sbi_system_shutdown(vcpu, run, KVM_SYSTEM_EVENT_SHUTDOWN); - next_sepc = false; - ret = 0; + *exit = true; break; case SBI_EXT_0_1_REMOTE_FENCE_I: case SBI_EXT_0_1_REMOTE_SFENCE_VMA: case SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID: if (cp->a0) hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0, - &utrap); + utrap); else hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; - if (utrap.scause) { - utrap.sepc = cp->sepc; - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); - next_sepc = false; + if (utrap->scause) break; - } + cpumask_clear(&cm); for_each_set_bit(i, &hmask, BITS_PER_LONG) { rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i); @@ -154,22 +162,97 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) } riscv_cpuid_to_hartid_mask(&cm, &hm); if (cp->a7 == SBI_EXT_0_1_REMOTE_FENCE_I) - sbi_remote_fence_i(cpumask_bits(&hm)); + ret = sbi_remote_fence_i(cpumask_bits(&hm)); else if (cp->a7 == SBI_EXT_0_1_REMOTE_SFENCE_VMA) - sbi_remote_hfence_vvma(cpumask_bits(&hm), + ret = sbi_remote_hfence_vvma(cpumask_bits(&hm), cp->a1, cp->a2); else - sbi_remote_hfence_vvma_asid(cpumask_bits(&hm), + ret = sbi_remote_hfence_vvma_asid(cpumask_bits(&hm), cp->a1, cp->a2, cp->a3); break; default: + ret = -EINVAL; + break; + } + + return ret; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = { + .extid_start = SBI_EXT_0_1_SET_TIMER, + .extid_end = SBI_EXT_0_1_SHUTDOWN, + .handler = kvm_sbi_ext_v01_handler, +}; + +static const struct kvm_vcpu_sbi_extension *sbi_ext[] = { + &vcpu_sbi_ext_v01, +}; + +const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(unsigned long extid) +{ + int i = 0; + + for (i = 0; i < ARRAY_SIZE(sbi_ext); i++) { + if (sbi_ext[i]->extid_start <= extid && + sbi_ext[i]->extid_end >= extid) + return sbi_ext[i]; + } + + return NULL; +} + +int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + int ret = 1; + bool next_sepc = true; + bool userspace_exit = false; + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + const struct kvm_vcpu_sbi_extension *sbi_ext; + struct kvm_cpu_trap utrap = { 0 }; + unsigned long out_val = 0; + bool ext_is_v01 = false; + + sbi_ext = kvm_vcpu_sbi_find_ext(cp->a7); + if (sbi_ext && sbi_ext->handler) { + if (cp->a7 >= SBI_EXT_0_1_SET_TIMER && + cp->a7 <= SBI_EXT_0_1_SHUTDOWN) + ext_is_v01 = true; + ret = sbi_ext->handler(vcpu, run, &out_val, &utrap, &userspace_exit); + } else { /* Return error for unsupported SBI calls */ cp->a0 = SBI_ERR_NOT_SUPPORTED; - break; + goto ecall_done; + } + + /* Handle special error cases i.e trap, exit or userspace forward */ + if (utrap.scause) { + /* No need to increment sepc or exit ioctl loop */ + ret = 1; + utrap.sepc = cp->sepc; + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); + next_sepc = false; + goto ecall_done; } + /* Exit ioctl loop or Propagate the error code the guest */ + if (userspace_exit) { + next_sepc = false; + ret = 0; + } else { + /** + * SBI extension handler always returns an Linux error code. Convert + * it to the SBI specific error code that can be propagated the SBI + * caller. + */ + ret = kvm_linux_err_map_sbi(ret); + cp->a0 = ret; + ret = 1; + } +ecall_done: if (next_sepc) cp->sepc += 4; + if (!ext_is_v01) + cp->a1 = out_val; return ret; }