Re: [PATCH 0/9][btrfs-progs] Remove unused dirstream variable

[David Sterba <dsterba@suse.cz>]

On Sat, Dec 30, 2023 at 12:20:54PM +0100, Goffredo Baroncelli wrote:
> On 14/12/2023 17.17, David Sterba wrote:
> > On Sat, Dec 09, 2023 at 07:53:20PM +0100, Goffredo Baroncelli wrote:
> >> From: Goffredo Baroncelli <kreijack@inwind.it>
> >>
> >> For historical reason, the helpers [btrfs_]open_[file_or_]dir() work with
> >> directory returning the 'fd' and a 'dirstream' variable returned by
> >> opendir(3).
> >>
> >> If the path is a file, the 'fd' is computed from open(2) and
> >> dirstream is set to NULL.
> >> If the path is a directory, first the directory is opened by opendir(3), then
> >> the 'fd' is computed using dirfd(3).
> >> However the 'dirstream' returned by opendir(3) is left open until 'fd'
> >> is not needed anymore.
> >>
> >> In near every case the 'dirstream' variable is not used. Only 'fd' is
> >> used.
> > 
> > As I'm reading dirfd manual page, dirfd returns the internal file
> > descriptor of the dirstream and it gets closed after call to closedir().
> > This means if we pass a directory and want a file descriptor then its
> > lifetime matches the correspoinding DIR.
> > 
> >> A call to close_file_or_dir() freed both 'fd' and 'dirstream'.
> >>
> >> Aim of this patch set is to getrid of this complexity; when the path of
> >> a directory is passed, the fd is get directly using open(path, O_RDONLY):
> >> so we don't need to use readdir(3) and to maintain the not used variable
> >> 'dirstream'.
> > 
> > Does this work the same way as with the dirstream?
> > 
> 
> Hi David, are you interested in this patch ? I think that it is a
> great simplification.

Yes, it's a good cleanup, I'll get to that after 6.7 is released.