From patchwork Tue Mar 13 16:18:40 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Tokarev X-Patchwork-Id: 146440 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 503AFB6F13 for ; Wed, 14 Mar 2012 03:19:37 +1100 (EST) Received: from localhost ([::1]:36096 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S7URi-0004FE-LL for incoming@patchwork.ozlabs.org; Tue, 13 Mar 2012 12:19:34 -0400 Received: from eggs.gnu.org ([208.118.235.92]:44997) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S7URX-0004BQ-Ep for qemu-devel@nongnu.org; Tue, 13 Mar 2012 12:19:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1S7UR2-0007V1-P1 for qemu-devel@nongnu.org; Tue, 13 Mar 2012 12:19:23 -0400 Received: from isrv.corpit.ru ([86.62.121.231]:39804) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S7UR2-0007TT-I4 for qemu-devel@nongnu.org; Tue, 13 Mar 2012 12:18:52 -0400 Received: from gandalf.tls.msk.ru (mjt.vpn.tls.msk.ru [192.168.177.99]) by isrv.corpit.ru (Postfix) with ESMTP id CBBE2A09C2; Tue, 13 Mar 2012 20:18:49 +0400 (MSK) Received: by gandalf.tls.msk.ru (Postfix, from userid 1000) id 50BE365DB; Tue, 13 Mar 2012 20:18:49 +0400 (MSK) From: Michael Tokarev To: qemu-devel@nongnu.org Date: Tue, 13 Mar 2012 20:18:40 +0400 Message-Id: <1331655521-5986-1-git-send-email-mjt@msgid.tls.msk.ru> X-Mailer: git-send-email 1.7.9.1 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 86.62.121.231 Cc: Stefan Hajnoczi , Michael Tokarev Subject: [Qemu-devel] [PATCH (trivial)] no need to use bdrv_pread() in format guessing code when we can use bdrv_read() directly 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 block.c:find_image_format() calls bdrv_pread() to read first 2048 bytes from the device to guess its format. This function can use bdrv_read() directly since the the read is done on sector boundary. Signed-off-by: Michael Tokarev --- block.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/block.c b/block.c index b88ee90..6b5bcaf 100644 --- a/block.c +++ b/block.c @@ -469,7 +469,7 @@ static int find_image_format(const char *filename, BlockDriver **pdrv) return ret; } - ret = bdrv_pread(bs, 0, buf, sizeof(buf)); + ret = bdrv_read(bs, 0, buf, sizeof(buf) / BDRV_BLOCK_SIZE); bdrv_delete(bs); if (ret < 0) { *pdrv = NULL;