Re: [PATCH] btrfs: fix directory offsets for '.' and '..' entries

[Tsutomu Itoh <t-itoh@jp.fujitsu.com>]

The same patch has been posted about one month ago.

  http://marc.info/?l=linux-btrfs&m=131363399500506&w=2

Thanks,
Tsutomu


(2011/09/12 5:33), Grazvydas Ignotas wrote:
> Currently getdents syscall returns wrong offset for '.' directory entry,
> which confuses some programs like wine. This can be observed with an
> example program getdents(2) manpage:
> 
> $ ./a.out /testfs/
> --------------- nread=96 ---------------
> i-node#  file type  d_reclen  d_off   d_name
>      256  directory    24          2  .
>      256  directory    24          2  ..
>      257  regular      24          3  a
>      258  regular      24 2147483647  b
> 
> Fix this by passing correct offsets to filldir().
> 
> Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
> ---
>  fs/btrfs/inode.c |    5 ++---
>  1 files changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index 0ccc743..5e7460b 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -4125,7 +4125,7 @@ static int btrfs_real_readdir(struct file *filp, void *dirent,
>  
>  	/* special case for "." */
>  	if (filp->f_pos == 0) {
> -		over = filldir(dirent, ".", 1, 1, btrfs_ino(inode), DT_DIR);
> +		over = filldir(dirent, ".", 1, 0, btrfs_ino(inode), DT_DIR);
>  		if (over)
>  			return 0;
>  		filp->f_pos = 1;
> @@ -4133,8 +4133,7 @@ static int btrfs_real_readdir(struct file *filp, void *dirent,
>  	/* special case for .., just use the back ref */
>  	if (filp->f_pos == 1) {
>  		u64 pino = parent_ino(filp->f_path.dentry);
> -		over = filldir(dirent, "..", 2,
> -			       2, pino, DT_DIR);
> +		over = filldir(dirent, "..", 2, 1, pino, DT_DIR);
>  		if (over)
>  			return 0;
>  		filp->f_pos = 2;