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=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 1E0FAC4BA3B for ; Thu, 27 Feb 2020 10:19:00 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 DDE832468D for ; Thu, 27 Feb 2020 10:18:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="cHlfD8fQ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DDE832468D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:56628 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j7GFv-00082h-0Z for qemu-devel@archiver.kernel.org; Thu, 27 Feb 2020 05:18:59 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:39914) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j7GB0-0003BI-JW for qemu-devel@nongnu.org; Thu, 27 Feb 2020 05:13:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j7GAz-0006tE-0Y for qemu-devel@nongnu.org; Thu, 27 Feb 2020 05:13:54 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:24778 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j7GAy-0006og-T3 for qemu-devel@nongnu.org; Thu, 27 Feb 2020 05:13:52 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1582798432; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=C9/Crd0sxE5CGHffwV6wijir6jtZAmFeRZbzyOdoPiE=; b=cHlfD8fQgo6bB46WYAdN/8svSMd1LdnGP2LtvXmXBw7W8wi9jW2YUR01UU5EYcs/pC3h2P 7KoJjt0Vx//gNVCDVMNB8tS3W+OcnVoi9UDzfPKldj/uhrlkgpR8Wbel0uSaDCH/qruJBJ Gd77kcUGfBtuhRRRiv+vzj/Ik5i9TKA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-307-2Xa-M6DDMpu9wafMM75uVQ-1; Thu, 27 Feb 2020 05:13:50 -0500 X-MC-Unique: 2Xa-M6DDMpu9wafMM75uVQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 34B2D1005514; Thu, 27 Feb 2020 10:13:49 +0000 (UTC) Received: from t480s.redhat.com (ovpn-116-36.ams2.redhat.com [10.36.116.36]) by smtp.corp.redhat.com (Postfix) with ESMTP id A1C016E3EE; Thu, 27 Feb 2020 10:13:46 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v3 07/15] util/mmap-alloc: Factor out calculation of the pagesize for the guard page Date: Thu, 27 Feb 2020 11:11:57 +0100 Message-Id: <20200227101205.5616-8-david@redhat.com> In-Reply-To: <20200227101205.5616-1-david@redhat.com> References: <20200227101205.5616-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , "Michael S . Tsirkin" , Igor Kotrasinski , David Hildenbrand , "Dr . David Alan Gilbert" , Peter Xu , Greg Kurz , Murilo Opsfelder Araujo , Igor Mammedov , Paolo Bonzini , Richard Henderson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Let's factor out calculating the size of the guard page and rename the variable to make it clearer that this pagesize only applies to the guard page. Cc: "Michael S. Tsirkin" Cc: Murilo Opsfelder Araujo Cc: Greg Kurz Cc: Eduardo Habkost Cc: "Dr. David Alan Gilbert" Cc: Igor Mammedov Signed-off-by: David Hildenbrand --- util/mmap-alloc.c | 31 ++++++++++++++++--------------- 1 file changed, 16 insertions(+), 15 deletions(-) diff --git a/util/mmap-alloc.c b/util/mmap-alloc.c index 27dcccd8ec..f0277f9fad 100644 --- a/util/mmap-alloc.c +++ b/util/mmap-alloc.c @@ -82,17 +82,27 @@ size_t qemu_mempath_getpagesize(const char *mem_path) return qemu_real_host_page_size; } =20 +static inline size_t mmap_guard_pagesize(int fd) +{ +#if defined(__powerpc64__) && defined(__linux__) + /* Mappings in the same segment must share the same page size */ + return qemu_fd_getpagesize(fd); +#else + return qemu_real_host_page_size; +#endif +} + void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared, bool is_pmem) { + const size_t guard_pagesize =3D mmap_guard_pagesize(fd); int flags; int map_sync_flags =3D 0; int guardfd; size_t offset; - size_t pagesize; size_t total; void *guardptr; void *ptr; @@ -113,8 +123,7 @@ void *qemu_ram_mmap(int fd, * anonymous memory is OK. */ flags =3D MAP_PRIVATE; - pagesize =3D qemu_fd_getpagesize(fd); - if (fd =3D=3D -1 || pagesize =3D=3D qemu_real_host_page_size) { + if (fd =3D=3D -1 || guard_pagesize =3D=3D qemu_real_host_page_size) { guardfd =3D -1; flags |=3D MAP_ANONYMOUS; } else { @@ -123,7 +132,6 @@ void *qemu_ram_mmap(int fd, } #else guardfd =3D -1; - pagesize =3D qemu_real_host_page_size; flags =3D MAP_PRIVATE | MAP_ANONYMOUS; #endif =20 @@ -135,7 +143,7 @@ void *qemu_ram_mmap(int fd, =20 assert(is_power_of_2(align)); /* Always align to host page size */ - assert(align >=3D pagesize); + assert(align >=3D guard_pagesize); =20 flags =3D MAP_FIXED; flags |=3D fd =3D=3D -1 ? MAP_ANONYMOUS : 0; @@ -189,8 +197,8 @@ void *qemu_ram_mmap(int fd, * a guard page guarding against potential buffer overflows. */ total -=3D offset; - if (total > size + pagesize) { - munmap(ptr + size + pagesize, total - size - pagesize); + if (total > size + guard_pagesize) { + munmap(ptr + size + guard_pagesize, total - size - guard_pagesize)= ; } =20 return ptr; @@ -198,15 +206,8 @@ void *qemu_ram_mmap(int fd, =20 void qemu_ram_munmap(int fd, void *ptr, size_t size) { - size_t pagesize; - if (ptr) { /* Unmap both the RAM block and the guard page */ -#if defined(__powerpc64__) && defined(__linux__) - pagesize =3D qemu_fd_getpagesize(fd); -#else - pagesize =3D qemu_real_host_page_size; -#endif - munmap(ptr, size + pagesize); + munmap(ptr, size + mmap_guard_pagesize(fd)); } } --=20 2.24.1