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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 15BE2C4CEC5 for ; Thu, 12 Sep 2019 12:02:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC3E920830 for ; Thu, 12 Sep 2019 12:02:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731561AbfILMCo (ORCPT ); Thu, 12 Sep 2019 08:02:44 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:56048 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1731106AbfILMCo (ORCPT ); Thu, 12 Sep 2019 08:02:44 -0400 Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x8CBwTRJ124636 for ; Thu, 12 Sep 2019 08:02:43 -0400 Received: from e06smtp04.uk.ibm.com (e06smtp04.uk.ibm.com [195.75.94.100]) by mx0a-001b2d01.pphosted.com with ESMTP id 2uyktpmka0-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 12 Sep 2019 08:02:42 -0400 Received: from localhost by e06smtp04.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Thu, 12 Sep 2019 13:02:34 +0100 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06avi18878370.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x8CC2XSN38469942 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 12 Sep 2019 12:02:33 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B8AB4AE9DF; Thu, 12 Sep 2019 11:36:50 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5C3C7AE9D8; Thu, 12 Sep 2019 11:36:49 +0000 (GMT) Received: from localhost.localdomain (unknown [9.145.92.148]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 12 Sep 2019 11:36:49 +0000 (GMT) Subject: Re: [PATCH 05/13] KVM: Refactor error handling for setting memory region To: Sean Christopherson , James Hogan , Paul Mackerras , Christian Borntraeger , Paolo Bonzini , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Marc Zyngier Cc: David Hildenbrand , Cornelia Huck , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , James Morse , Julien Thierry , Suzuki K Pouloze , linux-mips@vger.kernel.org, kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org References: <20190911185038.24341-1-sean.j.christopherson@intel.com> <20190911185038.24341-6-sean.j.christopherson@intel.com> From: Janosch Frank Openpgp: preference=signencrypt Autocrypt: addr=frankja@linux.ibm.com; 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Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <20190911185038.24341-6-sean.j.christopherson@intel.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="Bm0JecVlrjrc0FKCyusctXhutbwL6ZTpe" X-TM-AS-GCONF: 00 x-cbid: 19091212-0016-0000-0000-000002AA674A X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19091212-0017-0000-0000-0000330AF860 Message-Id: <9773a72d-2a58-fbb1-ed2b-82af0bb5f49a@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-09-12_05:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=935 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1909120129 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --Bm0JecVlrjrc0FKCyusctXhutbwL6ZTpe Content-Type: multipart/mixed; boundary="6J8eeynfSebyZsyGavbEUWKxUSMvfibQv"; protected-headers="v1" From: Janosch Frank To: Sean Christopherson , James Hogan , Paul Mackerras , Christian Borntraeger , Paolo Bonzini , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Marc Zyngier Cc: David Hildenbrand , Cornelia Huck , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , James Morse , Julien Thierry , Suzuki K Pouloze , linux-mips@vger.kernel.org, kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org Message-ID: <9773a72d-2a58-fbb1-ed2b-82af0bb5f49a@linux.ibm.com> Subject: Re: [PATCH 05/13] KVM: Refactor error handling for setting memory region References: <20190911185038.24341-1-sean.j.christopherson@intel.com> <20190911185038.24341-6-sean.j.christopherson@intel.com> In-Reply-To: <20190911185038.24341-6-sean.j.christopherson@intel.com> --6J8eeynfSebyZsyGavbEUWKxUSMvfibQv Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 9/11/19 8:50 PM, Sean Christopherson wrote: > Replace a big pile o' gotos with returns to make it more obvious what > error code is being returned, and to prepare for refactoring the > functional, i.e. post-checks, portion of __kvm_set_memory_region(). >=20 > Signed-off-by: Sean Christopherson Definitely necessary Reviewed-by: Janosch Frank > --- > virt/kvm/kvm_main.c | 40 ++++++++++++++++++---------------------- > 1 file changed, 18 insertions(+), 22 deletions(-) >=20 > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index ea8f2f37096f..8306ce3345a6 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -929,34 +929,33 @@ int __kvm_set_memory_region(struct kvm *kvm, > =20 > r =3D check_memory_region_flags(mem); > if (r) > - goto out; > + return r; > =20 > - r =3D -EINVAL; > as_id =3D mem->slot >> 16; > id =3D (u16)mem->slot; > =20 > /* General sanity checks */ > if (mem->memory_size & (PAGE_SIZE - 1)) > - goto out; > + return -EINVAL; > if (mem->guest_phys_addr & (PAGE_SIZE - 1)) > - goto out; > + return -EINVAL; > /* We can read the guest memory with __xxx_user() later on. */ > if ((id < KVM_USER_MEM_SLOTS) && > ((mem->userspace_addr & (PAGE_SIZE - 1)) || > !access_ok((void __user *)(unsigned long)mem->userspace_addr, > mem->memory_size))) > - goto out; > + return -EINVAL; > if (as_id >=3D KVM_ADDRESS_SPACE_NUM || id >=3D KVM_MEM_SLOTS_NUM) > - goto out; > + return -EINVAL; > if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr) > - goto out; > + return -EINVAL; > =20 > slot =3D id_to_memslot(__kvm_memslots(kvm, as_id), id); > base_gfn =3D mem->guest_phys_addr >> PAGE_SHIFT; > npages =3D mem->memory_size >> PAGE_SHIFT; > =20 > if (npages > KVM_MEM_MAX_NR_PAGES) > - goto out; > + return -EINVAL; > =20 > new =3D old =3D *slot; > =20 > @@ -973,20 +972,18 @@ int __kvm_set_memory_region(struct kvm *kvm, > if ((new.userspace_addr !=3D old.userspace_addr) || > (npages !=3D old.npages) || > ((new.flags ^ old.flags) & KVM_MEM_READONLY)) > - goto out; > + return -EINVAL; > =20 > if (base_gfn !=3D old.base_gfn) > change =3D KVM_MR_MOVE; > else if (new.flags !=3D old.flags) > change =3D KVM_MR_FLAGS_ONLY; > - else { /* Nothing to change. */ > - r =3D 0; > - goto out; > - } > + else /* Nothing to change. */ > + return 0; > } > } else { > if (!old.npages) > - goto out; > + return -EINVAL; > =20 > change =3D KVM_MR_DELETE; > new.base_gfn =3D 0; > @@ -995,29 +992,29 @@ int __kvm_set_memory_region(struct kvm *kvm, > =20 > if ((change =3D=3D KVM_MR_CREATE) || (change =3D=3D KVM_MR_MOVE)) { > /* Check for overlaps */ > - r =3D -EEXIST; > kvm_for_each_memslot(slot, __kvm_memslots(kvm, as_id)) { > if (slot->id =3D=3D id) > continue; > if (!((base_gfn + npages <=3D slot->base_gfn) || > (base_gfn >=3D slot->base_gfn + slot->npages))) > - goto out; > + return -EEXIST; > } > } > =20 > - r =3D -ENOMEM; > - > /* Allocate/free page dirty bitmap as needed */ > if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES)) > new.dirty_bitmap =3D NULL; > else if (!new.dirty_bitmap) { > - if (kvm_create_dirty_bitmap(&new) < 0) > - goto out; > + r =3D kvm_create_dirty_bitmap(&new); > + if (r) > + return r; > } > =20 > slots =3D kvzalloc(sizeof(struct kvm_memslots), GFP_KERNEL_ACCOUNT); > - if (!slots) > + if (!slots) { > + r =3D -ENOMEM; > goto out_bitmap; > + } > memcpy(slots, __kvm_memslots(kvm, as_id), sizeof(struct kvm_memslots)= ); > =20 > if ((change =3D=3D KVM_MR_DELETE) || (change =3D=3D KVM_MR_MOVE)) { > @@ -1068,7 +1065,6 @@ int __kvm_set_memory_region(struct kvm *kvm, > out_bitmap: > if (new.dirty_bitmap && !old.dirty_bitmap) > kvm_destroy_dirty_bitmap(&new); > -out: > return r; > } > EXPORT_SYMBOL_GPL(__kvm_set_memory_region); >=20 --6J8eeynfSebyZsyGavbEUWKxUSMvfibQv-- --Bm0JecVlrjrc0FKCyusctXhutbwL6ZTpe Content-Type: application/pgp-signature; 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