On Tue, 18 Mar 2008 09:11:54 -0700 (PDT) [email protected] wrote:
> http://bugzilla.kernel.org/show_bug.cgi?id=10276
>
> Summary: directory ctime not updated by rename
> Product: File System
> Version: 2.5
> KernelVersion: 2.6.24.3
> Platform: All
> OS/Version: Linux
> Tree: Mainline
> Status: NEW
> Severity: normal
> Priority: P1
> Component: ext3
> AssignedTo: [email protected]
> ReportedBy: [email protected]
>
>
> Latest working kernel version:
> Earliest failing kernel version:
> Distribution: LFS
> Hardware Environment: 32bit x86
> Software Environment:
> Problem Description: Renaming a file into a directory so that an already
> existing file is overwritten, will not update the ctime on the directory. This
> seems to be the reason for certain failures with incremental backups (e.g.,
> with star).
>
> Steps to reproduce:
>
> Run the following commands and watch the output from stat. Upon the second run
> of rename, the ctime is not updated on the directory sub.
>
> rm -fr sub new &&
> mkdir sub &&
> stat sub &&
> sleep 2 &&
> echo running rename &&
> ./rename a &&
> stat sub &&
> sleep 2 &&
> echo running rename again &&
> ./rename b &&
> stat sub
>
>
> Here is rename.c:
>
> #include <unistd.h>
> #include <fcntl.h>
> #include <stdio.h>
> #include <stdlib.h>
> #include <sys/stat.h>
>
> int main(int argc, char** argv) {
> int fd;
>
> fd = open("new", O_WRONLY | O_NDELAY | O_TRUNC | O_CREAT, 0644);
> write(fd, argv[1], 1);
> close(fd);
> rename("new", "sub/x");
>
> return 0;
> }
>
Do we agree that this is a bug? If so, is it a VFS thing or a per-fs
thing?
Thanks.
On Tue, 18 Mar 2008 17:46:09 +0000 Al Viro <[email protected]> wrote:
> On Tue, Mar 18, 2008 at 10:00:23AM -0700, Andrew Morton wrote:
>
> > Do we agree that this is a bug? If so, is it a VFS thing or a per-fs
> > thing?
>
> The latter; all control over timestamps on directory operations is in
> filesystems.
OK
> Which filesystem it is, BTW?
ext3.
> E.g. ext2 has
> dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
> in ext2_set_link() (and the same in ext2_add_entry()/ext2_delete_entry()),
> so on all paths in ext2_rename() both parents will get ctime and mtime
> updated; so will the object being moved and the object being unlinked
> (explicitly in ext2_rename()).
On Tue, Mar 18, 2008 at 05:46:09PM +0000, Al Viro wrote:
> On Tue, Mar 18, 2008 at 10:00:23AM -0700, Andrew Morton wrote:
>
> > Do we agree that this is a bug? If so, is it a VFS thing or a per-fs
> > thing?
>
> The latter; all control over timestamps on directory operations is in
> filesystems. Which filesystem it is, BTW? E.g. ext2 has
Doh. ext3... OK, that's a bug; direct update of directory entry by
new_de->inode = cpu_to_le32(old_inode->i_ino);
needs an update of timestamps of new_dir.
On Tue, Mar 18, 2008 at 10:00:23AM -0700, Andrew Morton wrote:
> Do we agree that this is a bug? If so, is it a VFS thing or a per-fs
> thing?
The latter; all control over timestamps on directory operations is in
filesystems. Which filesystem it is, BTW? E.g. ext2 has
dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
in ext2_set_link() (and the same in ext2_add_entry()/ext2_delete_entry()),
so on all paths in ext2_rename() both parents will get ctime and mtime
updated; so will the object being moved and the object being unlinked
(explicitly in ext2_rename()).
Al Viro:
> The latter; all control over timestamps on directory operations is in
> filesystems. Which filesystem it is, BTW? E.g. ext2 has
> dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
> in ext2_set_link() (and the same in ext2_add_entry()/ext2_delete_entry()),
> so on all paths in ext2_rename() both parents will get ctime and mtime
> updated; so will the object being moved and the object being unlinked
> (explicitly in ext2_rename()).
Is it correct to update the mtime of renaming inode?
When it is a regular file the mtime is not updated, but a directory. I
have been wondering it for a long time.
$ stat -f .
File: "."
ID: c39e8aabce296ceb Namelen: 255 Type: ext2/ext3
Block size: 1024 Fundamental block size: 1024
Blocks: Total: 124442 Free: 122443 Available: 116018
Inodes: Total: 32256 Free: 32144
(actually it is ext2)
$ mkdir d1
$ stat d1
File: `d1'
Size: 1024 Blocks: 2 IO Block: 1024 directory
Device: 30ah/778d Inode: 2017 Links: 2
Access: (0755/drwxr-xr-x) Uid: ( 1000/ jro) Gid: ( 1000/ jro)
Access: 2008-03-20 12:33:57.000000000 +0900
Modify: 2008-03-20 12:33:57.000000000 +0900
Change: 2008-03-20 12:33:57.000000000 +0900
$ /tmp/rename d1 d2
(simply issues rename systemcall.)
$ stat d2
File: `d2'
Size: 1024 Blocks: 2 IO Block: 1024 directory
Device: 30ah/778d Inode: 2017 Links: 2
Access: (0755/drwxr-xr-x) Uid: ( 1000/ jro) Gid: ( 1000/ jro)
Access: 2008-03-20 12:33:57.000000000 +0900
Modify: 2008-03-20 12:34:11.000000000 +0900
Change: 2008-03-20 12:34:11.000000000 +0900
$
Junjiro Okajima