From patchwork Thu Mar 19 03:56:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aneesh Kumar K V X-Patchwork-Id: 1257914 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=kvm-ppc-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 48jY5d15pLz9sTX for ; Thu, 19 Mar 2020 14:57:40 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727314AbgCSD5k (ORCPT ); Wed, 18 Mar 2020 23:57:40 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:19470 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727234AbgCSD5j (ORCPT ); Wed, 18 Mar 2020 23:57:39 -0400 Received: from pps.filterd (m0187473.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 02J3WasW104649; Wed, 18 Mar 2020 23:57:25 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2yu8adxw1s-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 18 Mar 2020 23:57:24 -0400 Received: from m0187473.ppops.net (m0187473.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 02J3WlUb105170; Wed, 18 Mar 2020 23:57:24 -0400 Received: from ppma01wdc.us.ibm.com (fd.55.37a9.ip4.static.sl-reverse.com [169.55.85.253]) by mx0a-001b2d01.pphosted.com with ESMTP id 2yu8adxw13-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 18 Mar 2020 23:57:24 -0400 Received: from pps.filterd (ppma01wdc.us.ibm.com [127.0.0.1]) by ppma01wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 02J3uwWI029795; Thu, 19 Mar 2020 03:57:22 GMT Received: from b01cxnp22034.gho.pok.ibm.com (b01cxnp22034.gho.pok.ibm.com [9.57.198.24]) by ppma01wdc.us.ibm.com with ESMTP id 2yrpw6nmwa-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 19 Mar 2020 03:57:22 +0000 Received: from b01ledav004.gho.pok.ibm.com (b01ledav004.gho.pok.ibm.com [9.57.199.109]) by b01cxnp22034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 02J3vMAd44892464 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 19 Mar 2020 03:57:22 GMT Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2594B112062; Thu, 19 Mar 2020 03:57:22 +0000 (GMT) Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 715B6112067; Thu, 19 Mar 2020 03:57:18 +0000 (GMT) Received: from skywalker.ibmuc.com (unknown [9.199.34.213]) by b01ledav004.gho.pok.ibm.com (Postfix) with ESMTP; Thu, 19 Mar 2020 03:57:18 +0000 (GMT) From: "Aneesh Kumar K.V" To: linuxppc-dev@lists.ozlabs.org, mpe@ellerman.id.au, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kvm-ppc@vger.kernel.org Cc: npiggin@gmail.com, paulus@ozlabs.org, leonardo@linux.ibm.com, kirill@shutemov.name, "Aneesh Kumar K.V" , Alexey Kardashevskiy Subject: [PATCH v2 16/22] powerpc/kvm/book3s: Avoid using rmap to protect parallel page table update. Date: Thu, 19 Mar 2020 09:26:03 +0530 Message-Id: <20200319035609.158654-17-aneesh.kumar@linux.ibm.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200319035609.158654-1-aneesh.kumar@linux.ibm.com> References: <20200319035609.158654-1-aneesh.kumar@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.645 definitions=2020-03-18_10:2020-03-18,2020-03-18 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 lowpriorityscore=0 mlxscore=0 clxscore=1015 priorityscore=1501 spamscore=0 malwarescore=0 impostorscore=0 suspectscore=8 bulkscore=0 mlxlogscore=999 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2003190015 Sender: kvm-ppc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm-ppc@vger.kernel.org We now depend on kvm->mmu_lock Cc: Alexey Kardashevskiy Signed-off-by: Aneesh Kumar K.V --- arch/powerpc/kvm/book3s_64_vio_hv.c | 38 +++++++---------------------- 1 file changed, 9 insertions(+), 29 deletions(-) diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c index 8a6bf12d2e88..2176d0d225d2 100644 --- a/arch/powerpc/kvm/book3s_64_vio_hv.c +++ b/arch/powerpc/kvm/book3s_64_vio_hv.c @@ -75,8 +75,8 @@ struct kvmppc_spapr_tce_table *kvmppc_find_table(struct kvm *kvm, EXPORT_SYMBOL_GPL(kvmppc_find_table); #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE -static long kvmppc_rm_tce_to_ua(struct kvm *kvm, unsigned long tce, - unsigned long *ua, unsigned long **prmap) +static long kvmppc_rm_tce_to_ua(struct kvm *kvm, + unsigned long tce, unsigned long *ua) { unsigned long gfn = tce >> PAGE_SHIFT; struct kvm_memory_slot *memslot; @@ -88,9 +88,6 @@ static long kvmppc_rm_tce_to_ua(struct kvm *kvm, unsigned long tce, *ua = __gfn_to_hva_memslot(memslot, gfn) | (tce & ~(PAGE_MASK | TCE_PCI_READ | TCE_PCI_WRITE)); - if (prmap) - *prmap = &memslot->arch.rmap[gfn - memslot->base_gfn]; - return 0; } @@ -117,7 +114,7 @@ static long kvmppc_rm_tce_validate(struct kvmppc_spapr_tce_table *stt, if (iommu_tce_check_gpa(stt->page_shift, gpa)) return H_PARAMETER; - if (kvmppc_rm_tce_to_ua(stt->kvm, tce, &ua, NULL)) + if (kvmppc_rm_tce_to_ua(stt->kvm, tce, &ua)) return H_TOO_HARD; list_for_each_entry_lockless(stit, &stt->iommu_tables, next) { @@ -412,7 +409,7 @@ long kvmppc_rm_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, return ret; dir = iommu_tce_direction(tce); - if ((dir != DMA_NONE) && kvmppc_rm_tce_to_ua(vcpu->kvm, tce, &ua, NULL)) + if ((dir != DMA_NONE) && kvmppc_rm_tce_to_ua(vcpu->kvm, tce, &ua)) return H_PARAMETER; entry = ioba >> stt->page_shift; @@ -489,7 +486,6 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu, struct kvmppc_spapr_tce_table *stt; long i, ret = H_SUCCESS; unsigned long tces, entry, ua = 0; - unsigned long *rmap = NULL; unsigned long mmu_seq; bool prereg = false; struct kvmppc_spapr_tce_iommu_table *stit; @@ -531,7 +527,7 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu, */ struct mm_iommu_table_group_mem_t *mem; - if (kvmppc_rm_tce_to_ua(vcpu->kvm, tce_list, &ua, NULL)) + if (kvmppc_rm_tce_to_ua(vcpu->kvm, tce_list, &ua)) return H_TOO_HARD; mem = mm_iommu_lookup_rm(vcpu->kvm->mm, ua, IOMMU_PAGE_SIZE_4K); @@ -547,23 +543,9 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu, * We do not require memory to be preregistered in this case * so lock rmap and do __find_linux_pte_or_hugepte(). */ - if (kvmppc_rm_tce_to_ua(vcpu->kvm, tce_list, &ua, &rmap)) - return H_TOO_HARD; - - rmap = (void *) vmalloc_to_phys(rmap); - if (WARN_ON_ONCE_RM(!rmap)) + if (kvmppc_rm_tce_to_ua(vcpu->kvm, tce_list, &ua)) return H_TOO_HARD; - /* - * Synchronize with the MMU notifier callbacks in - * book3s_64_mmu_hv.c (kvm_unmap_hva_range_hv etc.). - * While we have the rmap lock, code running on other CPUs - * cannot finish unmapping the host real page that backs - * this guest real page, so we are OK to access the host - * real page. - */ - lock_rmap(rmap); - arch_spin_lock(&kvm->mmu_lock.rlock.raw_lock); if (kvmppc_rm_ua_to_hpa(vcpu, mmu_seq, ua, &tces)) { ret = H_TOO_HARD; @@ -583,7 +565,7 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu, unsigned long tce = be64_to_cpu(((u64 *)tces)[i]); ua = 0; - if (kvmppc_rm_tce_to_ua(vcpu->kvm, tce, &ua, NULL)) { + if (kvmppc_rm_tce_to_ua(vcpu->kvm, tce, &ua)) { ret = H_PARAMETER; goto invalidate_exit; } @@ -608,10 +590,8 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu, iommu_tce_kill_rm(stit->tbl, entry, npages); unlock_exit: - if (rmap) - unlock_rmap(rmap); - - arch_spin_unlock(&kvm->mmu_lock.rlock.raw_lock); + if (!prereg) + arch_spin_unlock(&kvm->mmu_lock.rlock.raw_lock); return ret; }