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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham 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 EAC4CC4BA06 for ; Thu, 27 Feb 2020 07:30:50 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A464120714 for ; Thu, 27 Feb 2020 07:30:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A464120714 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 48SkqD6nfYzDr1f for ; Thu, 27 Feb 2020 18:30:48 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0b-001b2d01.pphosted.com; envelope-from=aneesh.kumar@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 48Sk4z5tYZzDqlB for ; Thu, 27 Feb 2020 17:57:39 +1100 (AEDT) Received: from pps.filterd (m0127361.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01R6qUZf000716; Thu, 27 Feb 2020 01:57:34 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ydhhny9a0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 27 Feb 2020 01:57:33 -0500 Received: from m0127361.ppops.net (m0127361.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 01R6qVkB000730; Thu, 27 Feb 2020 01:57:32 -0500 Received: from ppma04dal.us.ibm.com (7a.29.35a9.ip4.static.sl-reverse.com [169.53.41.122]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ydhhny993-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 27 Feb 2020 01:57:32 -0500 Received: from pps.filterd (ppma04dal.us.ibm.com [127.0.0.1]) by ppma04dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 01R6ujdD017831; Thu, 27 Feb 2020 06:57:31 GMT Received: from b01cxnp22033.gho.pok.ibm.com (b01cxnp22033.gho.pok.ibm.com [9.57.198.23]) by ppma04dal.us.ibm.com with ESMTP id 2ydcmkx472-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 27 Feb 2020 06:57:31 +0000 Received: from b01ledav001.gho.pok.ibm.com (b01ledav001.gho.pok.ibm.com [9.57.199.106]) by b01cxnp22033.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 01R6vUE341615802 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 27 Feb 2020 06:57:30 GMT Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 9411B28058; Thu, 27 Feb 2020 06:57:30 +0000 (GMT) Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6F22E28059; Thu, 27 Feb 2020 06:57:28 +0000 (GMT) Received: from skywalker.in.ibm.com (unknown [9.204.201.20]) by b01ledav001.gho.pok.ibm.com (Postfix) with ESMTP; Thu, 27 Feb 2020 06:57:28 +0000 (GMT) From: "Aneesh Kumar K.V" To: npiggin@gmail.com, paulus@samba.org, mpe@ellerman.id.au, kirill@shutemov.name Subject: [RFC PATCH 17/21] powerpc/kvm/book3s: Avoid using rmap to protect parallel page table update. Date: Thu, 27 Feb 2020 12:26:16 +0530 Message-Id: <20200227065620.50804-18-aneesh.kumar@linux.ibm.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200227065620.50804-1-aneesh.kumar@linux.ibm.com> References: <20200227065620.50804-1-aneesh.kumar@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.572 definitions=2020-02-27_01:2020-02-26, 2020-02-27 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 phishscore=0 bulkscore=0 suspectscore=0 clxscore=1015 adultscore=0 lowpriorityscore=0 mlxscore=0 priorityscore=1501 malwarescore=0 impostorscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002270053 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Aneesh Kumar K.V" , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" We now depend on kvm->mmu_lock 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; } -- 2.24.1