From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756636AbYICU36 (ORCPT ); Wed, 3 Sep 2008 16:29:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756061AbYICU3p (ORCPT ); Wed, 3 Sep 2008 16:29:45 -0400 Received: from curtis.curtisfong.org ([66.43.110.51]:52897 "EHLO curtis.curtisfong.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755890AbYICU3o (ORCPT ); Wed, 3 Sep 2008 16:29:44 -0400 Date: Wed, 3 Sep 2008 13:29:38 -0700 From: Nye Liu To: linux-kernel@vger.kernel.org Cc: nyet@mrv.com Subject: [PATCH] INITRAMFS: Add option to preserve mtime from INITRAMFS cpio images Message-ID: <20080903202938.GA9065@curtisfong.org> References: <20080805195232.GA5183@curtisfong.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080805195232.GA5183@curtisfong.org> User-Agent: Mutt/1.5.16 (2007-06-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Resubmission of initramfs preserve mtime patch following Andrew Morton's suggestions. From: Nye Liu When unpacking the cpio into the initramfs, mtimes are not preserved by default. This patch adds an INITRAMFS_PRESERVE_MTIME option that allows mtimes stored in the cpio image to be used when constructing the initramfs. For embedded applications that run exclusively out of the initramfs, this is invaluable. Signed-off-by: Nye Liu diff --git a/init/initramfs.c b/init/initramfs.c index 644fc01..ebfc049 100644 --- a/init/initramfs.c +++ b/init/initramfs.c @@ -6,6 +6,7 @@ #include #include #include +#include static __initdata char *message; static void __init error(char *x) @@ -72,6 +73,38 @@ static void __init free_hash(void) } } +static __initdata LIST_HEAD(dir_list); +struct dir_entry { + struct list_head list; + char *name; + struct utimbuf mtime; +}; + +static void __init dir_add(const char *name, struct utimbuf mtime) +{ + struct dir_entry *de = kmalloc(sizeof(struct dir_entry), GFP_KERNEL); + if (!de) + panic("can't allocate dir_entry buffer"); + INIT_LIST_HEAD(&de->list); + de->name = kstrdup(name, GFP_KERNEL); + de->mtime = mtime; + list_add(&de->list, &dir_list); +} + +static void __init dir_utime(void) +{ + struct list_head *e, *tmp; + list_for_each_safe(e, tmp, &dir_list) { + struct dir_entry *de = list_entry(e, struct dir_entry, list); + list_del(e); + sys_utime(de->name, &de->mtime); + kfree(de->name); + kfree(de); + } +} + +static __initdata struct utimbuf mtime; + /* cpio header parsing */ static __initdata unsigned long ino, major, minor, nlink; @@ -97,6 +130,7 @@ static void __init parse_header(char *s) uid = parsed[2]; gid = parsed[3]; nlink = parsed[4]; + mtime.actime = mtime.modtime = parsed[5]; body_len = parsed[6]; major = parsed[7]; minor = parsed[8]; @@ -130,6 +164,7 @@ static inline void __init eat(unsigned n) count -= n; } +static __initdata char *vcollected; static __initdata char *collected; static __initdata int remains; static __initdata char *collect; @@ -271,6 +306,7 @@ static int __init do_name(void) if (wfd >= 0) { sys_fchown(wfd, uid, gid); sys_fchmod(wfd, mode); + vcollected = kstrdup(collected, GFP_KERNEL); state = CopyFile; } } @@ -278,12 +314,14 @@ static int __init do_name(void) sys_mkdir(collected, mode); sys_chown(collected, uid, gid); sys_chmod(collected, mode); + dir_add(collected, mtime); } else if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { if (maybe_link() == 0) { sys_mknod(collected, mode, rdev); sys_chown(collected, uid, gid); sys_chmod(collected, mode); + sys_utime(collected, &mtime); } } return 0; @@ -294,6 +332,8 @@ static int __init do_copy(void) if (count >= body_len) { sys_write(wfd, victim, body_len); sys_close(wfd); + sys_utime(vcollected, &mtime); + kfree(vcollected); eat(body_len); state = SkipIt; return 0; @@ -305,12 +345,26 @@ static int __init do_copy(void) } } +static long __init do_lutime(char __user *filename, + struct utimbuf __user *times) +{ + struct timespec t[2]; + + t[0].tv_sec = times->actime; + t[0].tv_nsec = 0; + t[1].tv_sec = times->modtime; + t[1].tv_nsec = 0; + + return do_utimes(AT_FDCWD, filename, t, AT_SYMLINK_NOFOLLOW); +} + static int __init do_symlink(void) { collected[N_ALIGN(name_len) + body_len] = '\0'; clean_path(collected, 0); sys_symlink(collected + N_ALIGN(name_len), collected); sys_lchown(collected, uid, gid); + do_lutime(collected, &mtime); state = SkipIt; next_state = Reset; return 0; @@ -466,6 +520,7 @@ static char * __init unpack_to_rootfs(char *buf, unsigned len, int check_only) buf += inptr; len -= inptr; } + dir_utime(); kfree(window); kfree(name_buf); kfree(symlink_buf);