EXPORTFS: handle NULL returns from fh_to_dentry()/fh_to_parent()

While 440037287c "[PATCH] switch all filesystems over to
d_obtain_alias" removed some cases where fh_to_dentry() and
fh_to_parent() could return NULL, there are still a few NULL returns
left in individual filesystems.  Thus it was a mistake for that commit
to remove the handling of NULL returns in the callers.

Revert those parts of 440037287c which removed the NULL handling.

(We could, alternatively, modify all implementations to return -ESTALE
instead of NULL, but that proves to require fixing a number of
filesystems, and in some cases it's arguably more natural to return
NULL.)

Thanks to David for original patch and Linus, Christoph, and Hugh for
review.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
J. Bruce Fields 2008-12-08 18:24:18 -05:00 committed by Linus Torvalds
parent 218d11a8b0
commit a4f4d6df53

View File

@ -367,6 +367,8 @@ struct dentry *exportfs_decode_fh(struct vfsmount *mnt, struct fid *fid,
* Try to get any dentry for the given file handle from the filesystem.
*/
result = nop->fh_to_dentry(mnt->mnt_sb, fid, fh_len, fileid_type);
if (!result)
result = ERR_PTR(-ESTALE);
if (IS_ERR(result))
return result;
@ -420,6 +422,8 @@ struct dentry *exportfs_decode_fh(struct vfsmount *mnt, struct fid *fid,
target_dir = nop->fh_to_parent(mnt->mnt_sb, fid,
fh_len, fileid_type);
if (!target_dir)
goto err_result;
err = PTR_ERR(target_dir);
if (IS_ERR(target_dir))
goto err_result;