Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756636AbXJBPxk (ORCPT ); Tue, 2 Oct 2007 11:53:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754849AbXJBPwc (ORCPT ); Tue, 2 Oct 2007 11:52:32 -0400 Received: from mail-gw2.sa.eol.hu ([212.108.200.109]:58971 "EHLO mail-gw2.sa.eol.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753947AbXJBPwb (ORCPT ); Tue, 2 Oct 2007 11:52:31 -0400 Message-Id: <20071002155217.370453674@szeredi.hu> References: <20071002155026.650555479@szeredi.hu> User-Agent: quilt/0.45-1 Date: Tue, 02 Oct 2007 17:50:31 +0200 From: Miklos Szeredi To: akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org Subject: [patch 05/12] VFS: allow filesystems to implement atomic open+truncate Content-Disposition: inline; filename=vfs_atomic_open_truncate.patch Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1720 Lines: 49 From: Miklos Szeredi Add a new attribute flag ATTR_OPEN, with the meaning: "truncation was initiated by open() due to the O_TRUNC flag". This way filesystems wanting to implement truncation within their ->open() method can ignore such truncate requests. This is a quick & dirty hack, but it comes for free. Signed-off-by: Miklos Szeredi --- Index: linux/fs/namei.c =================================================================== --- linux.orig/fs/namei.c 2007-09-25 21:32:04.000000000 +0200 +++ linux/fs/namei.c 2007-09-25 21:56:30.000000000 +0200 @@ -1667,8 +1667,10 @@ int may_open(struct nameidata *nd, int a error = locks_verify_locked(inode); if (!error) { DQUOT_INIT(inode); - - error = do_truncate(dentry, 0, ATTR_MTIME|ATTR_CTIME, NULL); + + error = do_truncate(dentry, 0, + ATTR_MTIME|ATTR_CTIME|ATTR_OPEN, + NULL); } put_write_access(inode); if (error) Index: linux/include/linux/fs.h =================================================================== --- linux.orig/include/linux/fs.h 2007-09-25 21:32:05.000000000 +0200 +++ linux/include/linux/fs.h 2007-09-25 21:56:30.000000000 +0200 @@ -337,6 +337,7 @@ typedef void (dio_iodone_t)(struct kiocb #define ATTR_KILL_SGID 4096 #define ATTR_FILE 8192 #define ATTR_KILL_PRIV 16384 +#define ATTR_OPEN 32768 /* Truncating from open(O_TRUNC) */ /* * This is the Inode Attributes structure, used for notify_change(). It -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/