From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Guangrong Subject: [PATCH v3 11/32] hostmem-file: use whole file size if possible Date: Sun, 11 Oct 2015 11:52:43 +0800 Message-ID: <1444535584-18220-12-git-send-email-guangrong.xiao@linux.intel.com> References: <1444535584-18220-1-git-send-email-guangrong.xiao@linux.intel.com> Cc: gleb@kernel.org, mtosatti@redhat.com, stefanha@redhat.com, mst@redhat.com, rth@twiddle.net, ehabkost@redhat.com, dan.j.williams@intel.com, kvm@vger.kernel.org, qemu-devel@nongnu.org, Xiao Guangrong To: pbonzini@redhat.com, imammedo@redhat.com Return-path: Received: from mga03.intel.com ([134.134.136.65]:57371 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751619AbbJJT6l (ORCPT ); Sat, 10 Oct 2015 15:58:41 -0400 In-Reply-To: <1444535584-18220-1-git-send-email-guangrong.xiao@linux.intel.com> Sender: kvm-owner@vger.kernel.org List-ID: 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 | 47 +++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 43 insertions(+), 4 deletions(-) diff --git a/backends/hostmem-file.c b/backends/hostmem-file.c index 9097a57..adf2835 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 +36,56 @@ 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, "can't create backend with size 0"); + return; + } + backend->force_prealloc = mem_prealloc; memory_region_init_ram_from_file(&backend->mr, OBJECT(backend), object_get_canonical_path(OBJECT(backend)), -- 1.8.3.1