From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1973C433E1 for ; Mon, 17 Aug 2020 21:47:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7BBB920738 for ; Mon, 17 Aug 2020 21:47:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="CsZeA/Tr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728747AbgHQVro (ORCPT ); Mon, 17 Aug 2020 17:47:44 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:64036 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728684AbgHQVrm (ORCPT ); Mon, 17 Aug 2020 17:47:42 -0400 Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 07HLX06C022116; Mon, 17 Aug 2020 17:47:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=dMt+pC/R1fCDXZgpWnO++JFNA2C1KN+mULCs5PQzh2o=; b=CsZeA/Tr1mW35bglI9xuOl157VF7mdV1+osOKHTGbi2PVzLaok/rmJX25wh73MQzU/Be CTbezTME2DltrhbS0upxOcee3IBJuqQenCUbrqUyxIxFBbQ+TwXJvc3TlGTh9RtWKEbV CzD5gJF5i76GMxoVxFw9uUgXRkBVYuCe+cDJT510tT60IT6fSMFmMhwZUzcndmzu7wFa VQz8Fly6Wjp7ZKK603rUeHNITXr7LwqX8jXAujnHOQTBWtlcEehexb1uAlxCjL/JZyny fZMgLmSOfFj3CuqH7SptB+j8hz33ZcLWiw15+A3Y/R6n7RYvbiryDRvjjdEjqUY5Nus9 WA== Received: from ppma03dal.us.ibm.com (b.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.11]) by mx0a-001b2d01.pphosted.com with ESMTP id 32yxagwur1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 17 Aug 2020 17:47:23 -0400 Received: from pps.filterd (ppma03dal.us.ibm.com [127.0.0.1]) by ppma03dal.us.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 07HLjMR3013750; Mon, 17 Aug 2020 21:47:22 GMT Received: from b01cxnp22035.gho.pok.ibm.com (b01cxnp22035.gho.pok.ibm.com [9.57.198.25]) by ppma03dal.us.ibm.com with ESMTP id 32xgqnwahn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 17 Aug 2020 21:47:22 +0000 Received: from b01ledav004.gho.pok.ibm.com (b01ledav004.gho.pok.ibm.com [9.57.199.109]) by b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 07HLlLrl29229450 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 17 Aug 2020 21:47:21 GMT Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CCFC0112062; Mon, 17 Aug 2020 21:47:21 +0000 (GMT) Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 26887112061; Mon, 17 Aug 2020 21:47:18 +0000 (GMT) Received: from morokweng.localdomain.com (unknown [9.211.138.167]) by b01ledav004.gho.pok.ibm.com (Postfix) with ESMTP; Mon, 17 Aug 2020 21:47:17 +0000 (GMT) From: Thiago Jung Bauermann To: iommu@lists.linux-foundation.org Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Konrad Rzeszutek Wilk , Christoph Hellwig , Marek Szyprowski , Robin Murphy , Michael Ellerman , Ram Pai , Satheesh Rajendran , Thiago Jung Bauermann Subject: [PATCH v2] powerpc/pseries/svm: Allocate SWIOTLB buffer anywhere in memory Date: Mon, 17 Aug 2020 18:46:58 -0300 Message-Id: <20200817214658.103093-1-bauerman@linux.ibm.com> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235,18.0.687 definitions=2020-08-17_15:2020-08-17,2020-08-17 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 adultscore=0 suspectscore=3 bulkscore=0 mlxlogscore=999 lowpriorityscore=0 impostorscore=0 phishscore=0 priorityscore=1501 spamscore=0 clxscore=1015 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2008170146 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org POWER secure guests (i.e., guests which use the Protection Execution Facility) need to use SWIOTLB to be able to do I/O with the hypervisor, but they don't need the SWIOTLB memory to be in low addresses since the hypervisor doesn't have any addressing limitation. This solves a SWIOTLB initialization problem we are seeing in secure guests with 128 GB of RAM: they are configured with 4 GB of crashkernel reserved memory, which leaves no space for SWIOTLB in low addresses. To do this, we use mostly the same code as swiotlb_init(), but allocate the buffer using memblock_alloc() instead of memblock_alloc_low(). We also need to add swiotlb_set_no_iotlb_memory() in order to set the no_iotlb_memory flag if initialization fails. Signed-off-by: Thiago Jung Bauermann --- arch/powerpc/include/asm/svm.h | 4 ++++ arch/powerpc/mm/mem.c | 6 +++++- arch/powerpc/platforms/pseries/svm.c | 27 +++++++++++++++++++++++++++ include/linux/swiotlb.h | 1 + kernel/dma/swiotlb.c | 5 +++++ 5 files changed, 42 insertions(+), 1 deletion(-) Changes from v1: - Open-code swiotlb_init() in arch-specific code, as suggested by Christoph. diff --git a/arch/powerpc/include/asm/svm.h b/arch/powerpc/include/asm/svm.h index 85580b30aba4..7546402d796a 100644 --- a/arch/powerpc/include/asm/svm.h +++ b/arch/powerpc/include/asm/svm.h @@ -15,6 +15,8 @@ static inline bool is_secure_guest(void) return mfmsr() & MSR_S; } +void __init svm_swiotlb_init(void); + void dtl_cache_ctor(void *addr); #define get_dtl_cache_ctor() (is_secure_guest() ? dtl_cache_ctor : NULL) @@ -25,6 +27,8 @@ static inline bool is_secure_guest(void) return false; } +static inline void svm_swiotlb_init(void) {} + #define get_dtl_cache_ctor() NULL #endif /* CONFIG_PPC_SVM */ diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index c2c11eb8dcfc..0f21bcb16405 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -50,6 +50,7 @@ #include #include #include +#include #include @@ -290,7 +291,10 @@ void __init mem_init(void) * back to to-down. */ memblock_set_bottom_up(true); - swiotlb_init(0); + if (is_secure_guest()) + svm_swiotlb_init(); + else + swiotlb_init(0); #endif high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); diff --git a/arch/powerpc/platforms/pseries/svm.c b/arch/powerpc/platforms/pseries/svm.c index 40c0637203d5..d592e663a8d6 100644 --- a/arch/powerpc/platforms/pseries/svm.c +++ b/arch/powerpc/platforms/pseries/svm.c @@ -7,6 +7,7 @@ */ #include +#include #include #include #include @@ -34,6 +35,32 @@ static int __init init_svm(void) } machine_early_initcall(pseries, init_svm); +/* + * Initialize SWIOTLB. Essentially the same as swiotlb_init(), except that it + * can allocate the buffer anywhere in memory. Since the hypervisor doesn't have + * any addressing limitation, we don't need to allocate it in low addresses. + */ +void __init svm_swiotlb_init(void) +{ + unsigned char *vstart; + unsigned long bytes, io_tlb_nslabs; + + io_tlb_nslabs = (swiotlb_size_or_default() >> IO_TLB_SHIFT); + io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); + + bytes = io_tlb_nslabs << IO_TLB_SHIFT; + + vstart = memblock_alloc(PAGE_ALIGN(bytes), PAGE_SIZE); + if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, false)) + return; + + if (io_tlb_start) + memblock_free_early(io_tlb_start, + PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT)); + pr_warn("Cannot allocate SWIOTLB buffer"); + swiotlb_set_no_iotlb_memory(true); +} + int set_memory_encrypted(unsigned long addr, int numpages) { if (!PAGE_ALIGNED(addr)) diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index 046bb94bd4d6..991e9f13e663 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -35,6 +35,7 @@ extern unsigned long swiotlb_nr_tbl(void); unsigned long swiotlb_size_or_default(void); extern int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs); extern void __init swiotlb_update_mem_attributes(void); +void __init swiotlb_set_no_iotlb_memory(bool value); /* * Enumeration for sync targets diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index c19379fabd20..ed2b8818ff67 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -132,6 +132,11 @@ early_param("swiotlb", setup_io_tlb_npages); static bool no_iotlb_memory; +void __init swiotlb_set_no_iotlb_memory(bool value) +{ + no_iotlb_memory = value; +} + unsigned long swiotlb_nr_tbl(void) { return unlikely(no_iotlb_memory) ? 0 : io_tlb_nslabs;