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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 70D50C433EF for ; Thu, 3 Mar 2022 19:40:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236225AbiCCTlk (ORCPT ); Thu, 3 Mar 2022 14:41:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33746 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236217AbiCCTky (ORCPT ); Thu, 3 Mar 2022 14:40:54 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 325B01A6353 for ; Thu, 3 Mar 2022 11:39:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646336364; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3S94nz0psd43uT5tjnVxrAMKMmNoTXAksjmb0Kl0LAY=; b=dZKl/rOcUDFJ6Y81TTXlB3mS60uzxWVEOdQst6HqHPoOBtb7aTp0WGcM8mbRO+YQF2hfWp GVQT1mJ1AMJd/6sy4aYl25QRA7ud3iFgpYrASVk5njzDXIk1LUZkk1EDN/7Y81HjhcZdyj iPZJDuIiKHu29lCCYVVYIazoe7tRSmM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-479-n1So81VfNoSEmDRHW6Em-w-1; Thu, 03 Mar 2022 14:39:21 -0500 X-MC-Unique: n1So81VfNoSEmDRHW6Em-w-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 77DC11883526; Thu, 3 Mar 2022 19:39:19 +0000 (UTC) Received: from virtlab701.virt.lab.eng.bos.redhat.com (virtlab701.virt.lab.eng.bos.redhat.com [10.19.152.228]) by smtp.corp.redhat.com (Postfix) with ESMTP id 87D5B5C64D; Thu, 3 Mar 2022 19:39:18 +0000 (UTC) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , David Hildenbrand , David Matlack , Ben Gardon , Mingwei Zhang Subject: [PATCH v4 28/30] KVM: selftests: Split out helper to allocate guest mem via memfd Date: Thu, 3 Mar 2022 14:38:40 -0500 Message-Id: <20220303193842.370645-29-pbonzini@redhat.com> In-Reply-To: <20220303193842.370645-1-pbonzini@redhat.com> References: <20220303193842.370645-1-pbonzini@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sean Christopherson Extract the code for allocating guest memory via memfd out of vm_userspace_mem_region_add() and into a new helper, kvm_memfd_alloc(). A future selftest to populate a guest with the maximum amount of guest memory will abuse KVM's memslots to alias guest memory regions to a single memfd-backed host region, i.e. needs to back a guest with memfd memory without a 1:1 association between a memslot and a memfd instance. No functional change intended. Signed-off-by: Sean Christopherson Message-Id: <20220226001546.360188-27-seanjc@google.com> Signed-off-by: Paolo Bonzini --- .../selftests/kvm/include/kvm_util_base.h | 1 + tools/testing/selftests/kvm/lib/kvm_util.c | 42 +++++++++++-------- 2 files changed, 25 insertions(+), 18 deletions(-) diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h index 573de0354175..92cef0ffb19e 100644 --- a/tools/testing/selftests/kvm/include/kvm_util_base.h +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h @@ -123,6 +123,7 @@ int kvm_memcmp_hva_gva(void *hva, struct kvm_vm *vm, const vm_vaddr_t gva, size_t len); void kvm_vm_elf_load(struct kvm_vm *vm, const char *filename); +int kvm_memfd_alloc(size_t size, bool hugepages); void vm_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent); diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index dcb8e96c6a54..1665a220abcb 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -718,6 +718,27 @@ void kvm_vm_free(struct kvm_vm *vmp) free(vmp); } +int kvm_memfd_alloc(size_t size, bool hugepages) +{ + int memfd_flags = MFD_CLOEXEC; + int fd, r; + + if (hugepages) + memfd_flags |= MFD_HUGETLB; + + fd = memfd_create("kvm_selftest", memfd_flags); + TEST_ASSERT(fd != -1, "memfd_create() failed, errno: %i (%s)", + errno, strerror(errno)); + + r = ftruncate(fd, size); + TEST_ASSERT(!r, "ftruncate() failed, errno: %i (%s)", errno, strerror(errno)); + + r = fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 0, size); + TEST_ASSERT(!r, "fallocate() failed, errno: %i (%s)", errno, strerror(errno)); + + return fd; +} + /* * Memory Compare, host virtual to guest virtual * @@ -970,24 +991,9 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm, region->mmap_size += alignment; region->fd = -1; - if (backing_src_is_shared(src_type)) { - int memfd_flags = MFD_CLOEXEC; - - if (src_type == VM_MEM_SRC_SHARED_HUGETLB) - memfd_flags |= MFD_HUGETLB; - - region->fd = memfd_create("kvm_selftest", memfd_flags); - TEST_ASSERT(region->fd != -1, - "memfd_create failed, errno: %i", errno); - - ret = ftruncate(region->fd, region->mmap_size); - TEST_ASSERT(ret == 0, "ftruncate failed, errno: %i", errno); - - ret = fallocate(region->fd, - FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 0, - region->mmap_size); - TEST_ASSERT(ret == 0, "fallocate failed, errno: %i", errno); - } + if (backing_src_is_shared(src_type)) + region->fd = kvm_memfd_alloc(region->mmap_size, + src_type == VM_MEM_SRC_SHARED_HUGETLB); region->mmap_start = mmap(NULL, region->mmap_size, PROT_READ | PROT_WRITE, -- 2.31.1