From patchwork Fri Apr 19 16:16:23 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vasant Karasulli X-Patchwork-Id: 13636597 Received: from mail-wm1-f47.google.com (mail-wm1-f47.google.com [209.85.128.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 58FE8135A54 for ; Fri, 19 Apr 2024 16:16:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.47 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713543406; cv=none; b=eLWrJEZBs6KNhAN7ykibZmOTtw+iNWOlAdseEe3RYJCbi+T96oDA/jRSSDaK4uGxclzM33S8LWmUfBvdmwL31/NOeEJ3lWVVJKyx6M+KNWEbrxwKHDkkOVsRThomcZTSA/aEFGM235v2u+YoaoRAUZBrexOYbHrwTFINejhSdMM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713543406; c=relaxed/simple; bh=sh0PZV/g72KQaq0W2lmfvw72SVzTXJwtX/DwYNPI0tI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=U+pd85ehPKI1AP4t3eyCwIX81VvUBsQwrcfRPba7SrBdCH+wskZb0dNaonGnwC7Hhv2XFHY5vm0AbesW6MUL7LgCLF7saZGk7GGO0StsaTsY+BRjoONBLH8mDDwj1DRGf8jwm220bEaVG03HxB5Db5FRSOACmUl/oJP3qmTArVs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=eaOoIb6a; arc=none smtp.client-ip=209.85.128.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="eaOoIb6a" Received: by mail-wm1-f47.google.com with SMTP id 5b1f17b1804b1-41550858cabso16512705e9.2 for ; Fri, 19 Apr 2024 09:16:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1713543401; x=1714148201; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=xNCVLIG2CMiyBOoYiM8IF0VeYwcjYl+48FesKHJM0yg=; b=eaOoIb6aWCKb9mFdZr90xgRjikCul+VcQZ5yCyZ8jlIsjWHXSEdVdr2PS7vH6tl+PV k/tfLGVHJxSBXIHyGCwL2igPhNqQs6wy7ajO6a5x1GvXse0vL+X+yTgxPMewku1N5QQP Cc88gblYMERJrlsIOpYLXKrCOH8BDh7kxgDGsFbDy65TbUovrPhylfuHTJGAWJUpS6YS eVgTPGx31ew3yCiOvvfgB9Lyyf07hasaZLsdoubAPahYYP9Rw/z2yh7+tk6xe11ED4bK LnTIIfB/1GQT0QAnRX+Q21GRQNK8znVTBLTkdBjvdONyn6uAuvByxaOMyEOicIwVDBtu kIcA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1713543401; x=1714148201; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=xNCVLIG2CMiyBOoYiM8IF0VeYwcjYl+48FesKHJM0yg=; b=ZM4nR0/mUIKTIv+tmn3Q7FRZ+YCpgZZCVaMQZUptvmydWaufg/B03tAsRmrOIK1vSn djLUTzez1V1cRDOWxEsG1BjJGLRZG8ZrzR+EyGPEx4Ozf7cDLIbIrQrcBOIMH+MN24KL uKFWRSbZZKrsdk/VjcJ17UeTcF34TAbA0give38IluGo9m0kH2gf0UAsHNJhVzG64LIi qZTo+ERfz3R24uzI5092kdrgehcHlpNdFdebrbyP5GGCYln7ALH1CAmKP66Oi00bkqko 04eyeIN9RKgX2VrUib+Cr5PGOeNKjta1YgS43qVZKWfL+OH3DPHGvdKA3Q2uYqIVZhia DwFA== X-Gm-Message-State: AOJu0YwRhuRV8lG8yUV9zAKc82IGsxN1nm7cal72mx455C7jGcvZXrQu +7M+GKMDEk/J0Uh0lgBURGBTkFtWMyCAkXCdK88vh/teIdX+KQ6GTsTeU0O4 X-Google-Smtp-Source: AGHT+IG18l2qfBuRVcPK89GfbtfN7WlilH6GFJfx3KEqOyWo0vAgoSayJZC/Nyhwc4g8DuYoz2sR7A== X-Received: by 2002:a05:600c:3b0f:b0:418:9713:866c with SMTP id m15-20020a05600c3b0f00b004189713866cmr1533443wms.5.1713543401232; Fri, 19 Apr 2024 09:16:41 -0700 (PDT) Received: from vasant-suse.suse.cz ([2001:9e8:ab5e:9e00:8bce:ff73:6d2f:5c25]) by smtp.gmail.com with ESMTPSA id je12-20020a05600c1f8c00b004183edc31adsm10742188wmb.44.2024.04.19.09.16.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Apr 2024 09:16:40 -0700 (PDT) From: vsntk18@gmail.com To: kvm@vger.kernel.org Cc: pbonzini@redhat.com, seanjc@google.com, jroedel@suse.de, papaluri@amd.com, andrew.jones@linux.dev, Vasant Karasulli , Varad Gautam , Marc Orr Subject: [kvm-unit-tests PATCH v7 11/11] x86: AMD SEV-ES: Handle string IO for IOIO #VC Date: Fri, 19 Apr 2024 18:16:23 +0200 Message-Id: <20240419161623.45842-12-vsntk18@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240419161623.45842-1-vsntk18@gmail.com> References: <20240419161623.45842-1-vsntk18@gmail.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Vasant Karasulli Using Linux's IOIO #VC processing logic. Signed-off-by: Varad Gautam Signed-off-by: Vasant Karasulli Reviewed-by: Marc Orr Tested-by: Marc Orr --- lib/x86/amd_sev_vc.c | 108 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 106 insertions(+), 2 deletions(-) -- 2.34.1 diff --git a/lib/x86/amd_sev_vc.c b/lib/x86/amd_sev_vc.c index 2a553db1..aca549b3 100644 --- a/lib/x86/amd_sev_vc.c +++ b/lib/x86/amd_sev_vc.c @@ -306,10 +306,46 @@ static enum es_result vc_ioio_exitinfo(struct es_em_ctxt *ctxt, u64 *exitinfo) return ES_OK; } +static enum es_result vc_insn_string_read(struct es_em_ctxt *ctxt, + void *src, unsigned char *buf, + unsigned int data_size, + unsigned int count, + bool backwards) +{ + int i, b = backwards ? -1 : 1; + + for (i = 0; i < count; i++) { + void *s = src + (i * data_size * b); + unsigned char *d = buf + (i * data_size); + + memcpy(d, s, data_size); + } + + return ES_OK; +} + +static enum es_result vc_insn_string_write(struct es_em_ctxt *ctxt, + void *dst, unsigned char *buf, + unsigned int data_size, + unsigned int count, + bool backwards) +{ + int i, s = backwards ? -1 : 1; + + for (i = 0; i < count; i++) { + void *d = dst + (i * data_size * s); + unsigned char *b = buf + (i * data_size); + + memcpy(d, b, data_size); + } + + return ES_OK; +} + static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) { struct ex_regs *regs = ctxt->regs; - u64 exit_info_1; + u64 exit_info_1, exit_info_2; enum es_result ret; ret = vc_ioio_exitinfo(ctxt, &exit_info_1); @@ -317,7 +353,75 @@ static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) return ret; if (exit_info_1 & IOIO_TYPE_STR) { - ret = ES_VMM_ERROR; + /* (REP) INS/OUTS */ + + bool df = ((regs->rflags & X86_EFLAGS_DF) == X86_EFLAGS_DF); + unsigned int io_bytes, exit_bytes; + unsigned int ghcb_count, op_count; + unsigned long es_base; + u64 sw_scratch; + + /* + * For the string variants with rep prefix the amount of in/out + * operations per #VC exception is limited so that the kernel + * has a chance to take interrupts and re-schedule while the + * instruction is emulated. + */ + io_bytes = (exit_info_1 >> 4) & 0x7; + ghcb_count = sizeof(ghcb->shared_buffer) / io_bytes; + + op_count = (exit_info_1 & IOIO_REP) ? regs->rcx : 1; + exit_info_2 = op_count < ghcb_count ? op_count : ghcb_count; + exit_bytes = exit_info_2 * io_bytes; + + es_base = 0; + + /* Read bytes of OUTS into the shared buffer */ + if (!(exit_info_1 & IOIO_TYPE_IN)) { + ret = vc_insn_string_read(ctxt, + (void *)(es_base + regs->rsi), + ghcb->shared_buffer, io_bytes, + exit_info_2, df); + if (ret) + return ret; + } + + /* + * Issue an VMGEXIT to the HV to consume the bytes from the + * shared buffer or to have it write them into the shared buffer + * depending on the instruction: OUTS or INS. + */ + sw_scratch = __pa(ghcb) + offsetof(struct ghcb, shared_buffer); + ghcb_set_sw_scratch(ghcb, sw_scratch); + ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_IOIO, + exit_info_1, exit_info_2); + if (ret != ES_OK) + return ret; + + /* Read bytes from shared buffer into the guest's destination. */ + if (exit_info_1 & IOIO_TYPE_IN) { + ret = vc_insn_string_write(ctxt, + (void *)(es_base + regs->rdi), + ghcb->shared_buffer, io_bytes, + exit_info_2, df); + if (ret) + return ret; + + if (df) + regs->rdi -= exit_bytes; + else + regs->rdi += exit_bytes; + } else { + if (df) + regs->rsi -= exit_bytes; + else + regs->rsi += exit_bytes; + } + + if (exit_info_1 & IOIO_REP) + regs->rcx -= exit_info_2; + + ret = regs->rcx ? ES_RETRY : ES_OK; } else { /* IN/OUT into/from rAX */