[GFS2] Clean up inode number handling

This patch cleans up the inode number handling code. The main difference
is that instead of looking up the inodes using a struct gfs2_inum_host
we now use just the no_addr member of this structure. The tests relating
to no_formal_ino can then be done by the calling code. This has
advantages in that we want to do different things in different code
paths if the no_formal_ino doesn't match. In the NFS patch we want to
return -ESTALE, but in the ->lookup() path, its a bug in the fs if the
no_formal_ino doesn't match and thus we can withdraw in this case.

In order to later fix bz #201012, we need to be able to look up an inode
without knowing no_formal_ino, as the only information that is known to
us is the on-disk location of the inode in question.

This patch will also help us to fix bz #236099 at a later date by
cleaning up a lot of the code in that area.

There are no user visible changes as a result of this patch and there
are no changes to the on-disk format either.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/dir.h b/fs/gfs2/dir.h
index 48fe890..8a468ca 100644
--- a/fs/gfs2/dir.h
+++ b/fs/gfs2/dir.h
@@ -16,15 +16,16 @@
 struct gfs2_inode;
 struct gfs2_inum;
 
-int gfs2_dir_search(struct inode *dir, const struct qstr *filename,
-		    struct gfs2_inum_host *inum, unsigned int *type);
+struct inode *gfs2_dir_search(struct inode *dir, const struct qstr *filename);
+int gfs2_dir_check(struct inode *dir, const struct qstr *filename,
+		   const struct gfs2_inode *ip);
 int gfs2_dir_add(struct inode *inode, const struct qstr *filename,
-		 const struct gfs2_inum_host *inum, unsigned int type);
+		 const struct gfs2_inode *ip, unsigned int type);
 int gfs2_dir_del(struct gfs2_inode *dip, const struct qstr *filename);
 int gfs2_dir_read(struct inode *inode, u64 *offset, void *opaque,
 		  filldir_t filldir);
 int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
-		   struct gfs2_inum_host *new_inum, unsigned int new_type);
+		   const struct gfs2_inode *nip, unsigned int new_type);
 
 int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip);