Re: [linux-cifs-client] [PATCH 2/3] cifs: add new cifs_iget_unix_basic function

[Christoph Hellwig <hch@infradead.org>]

On Sun, Apr 05, 2009 at 09:09:20AM -0400, Jeff Layton wrote:
> Add a new cifs_iget_unix function that uses iget5_locked to identify
> inodes. This will compare inodes based on the UniqueId value that
> the server provides when unix extensions are enabled. We also have
> mounts with unix extensions use that value in the i_ino field (after
> hashing it down to 32-bits on a 32-bit arches).

Note that i_ino and ino_t aren't actually all that important.  You
already do the iget comparisms based on the internal uniqueid, so the
only thing i_ino is used for is filling out the inode value in
generic_fattr.  I would suggest to fill it out explicitly in
cifs_getattr so that you can actually return a 64bit ino there which
is supported by stat64, possibly under and inode64 mount option.

> diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
> index d958044..be639ee 100644
> --- a/fs/cifs/dir.c
> +++ b/fs/cifs/dir.c
> @@ -187,18 +187,16 @@ int cifs_posix_open(char *full_path, struct inode **pinode,
>  	if (!pinode)
>  		goto posix_open_ret; /* caller does not need info */
>  
> -	if (*pinode == NULL) {
> -		__u64 unique_id = le64_to_cpu(presp_data->UniqueId);
> -		*pinode = cifs_new_inode(sb, &unique_id);
> -	}
> +	if (*pinode == NULL)
> +		*pinode = cifs_iget_unix_basic(sb, presp_data);
>  	/* else an inode was passed in. Update its info, don't create one */

Not directly related to this patch, but cifs_posix_open really needs
some restructuring.  The code up to the !pinode check should be the
basic underlying helper, and the call to cifs_iget_unix_basic and
posix_fill_in_inode should be moved to those callers that acutally need
it.