From patchwork Mon Oct 19 00:53:57 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiao Guangrong X-Patchwork-Id: 531967 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id CC300140307 for ; Mon, 19 Oct 2015 04:04:24 +1100 (AEDT) Received: from localhost ([::1]:34709 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZnrNe-0006lr-ME for incoming@patchwork.ozlabs.org; Sun, 18 Oct 2015 13:04:22 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42637) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZnrJL-00073t-Th for qemu-devel@nongnu.org; Sun, 18 Oct 2015 12:59:56 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZnrJK-0000Co-Vl for qemu-devel@nongnu.org; Sun, 18 Oct 2015 12:59:55 -0400 Received: from mga09.intel.com ([134.134.136.24]:58036) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZnrJK-0000CK-QE for qemu-devel@nongnu.org; Sun, 18 Oct 2015 12:59:54 -0400 Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga102.jf.intel.com with ESMTP; 18 Oct 2015 09:59:54 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.17,698,1437462000"; d="scan'208";a="583275352" Received: from xiaoreal1.sh.intel.com (HELO xiaoreal1.sh.intel.com.sh.intel.com) ([10.239.48.79]) by FMSMGA003.fm.intel.com with ESMTP; 18 Oct 2015 09:59:52 -0700 From: Xiao Guangrong To: pbonzini@redhat.com, imammedo@redhat.com Date: Mon, 19 Oct 2015 08:53:57 +0800 Message-Id: <1445216059-88521-12-git-send-email-guangrong.xiao@linux.intel.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1445216059-88521-1-git-send-email-guangrong.xiao@linux.intel.com> References: <1445216059-88521-1-git-send-email-guangrong.xiao@linux.intel.com> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 134.134.136.24 Cc: Xiao Guangrong , ehabkost@redhat.com, kvm@vger.kernel.org, mst@redhat.com, gleb@kernel.org, mtosatti@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com, dan.j.williams@intel.com, rth@twiddle.net Subject: [Qemu-devel] [PATCH v4 11/33] hostmem-file: use whole file size if possible X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Use the whole file size if @size is not specified which is useful if we want to directly pass a file to guest Signed-off-by: Xiao Guangrong --- backends/hostmem-file.c | 48 ++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 44 insertions(+), 4 deletions(-) diff --git a/backends/hostmem-file.c b/backends/hostmem-file.c index 9097a57..e1bc9ff 100644 --- a/backends/hostmem-file.c +++ b/backends/hostmem-file.c @@ -9,6 +9,9 @@ * This work is licensed under the terms of the GNU GPL, version 2 or later. * See the COPYING file in the top-level directory. */ +#include +#include + #include "qemu-common.h" #include "sysemu/hostmem.h" #include "sysemu/sysemu.h" @@ -33,20 +36,57 @@ struct HostMemoryBackendFile { char *mem_path; }; +static uint64_t get_file_size(const char *file) +{ + struct stat stat_buf; + uint64_t size = 0; + int fd; + + fd = open(file, O_RDONLY); + if (fd < 0) { + return 0; + } + + if (stat(file, &stat_buf) < 0) { + goto exit; + } + + if ((S_ISBLK(stat_buf.st_mode)) && !ioctl(fd, BLKGETSIZE64, &size)) { + goto exit; + } + + size = lseek(fd, 0, SEEK_END); + if (size == -1) { + size = 0; + } +exit: + close(fd); + return size; +} + static void file_backend_memory_alloc(HostMemoryBackend *backend, Error **errp) { HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(backend); - if (!backend->size) { - error_setg(errp, "can't create backend with size 0"); - return; - } if (!fb->mem_path) { error_setg(errp, "mem-path property not set"); return; } + if (!backend->size) { + /* + * use the whole file size if @size is not specified. + */ + backend->size = get_file_size(fb->mem_path); + } + + if (!backend->size) { + error_setg(errp, "failed to get file size for %s, can't create " + "backend on it", mem_path); + return; + } + backend->force_prealloc = mem_prealloc; memory_region_init_ram_from_file(&backend->mr, OBJECT(backend), object_get_canonical_path(OBJECT(backend)),