9p: Make the path walk logic more clear about when cloning is required

Cloning during a path component walk is only needed when the old fid
used for the walk operation is the root fid. Make that clear by
comparing the two fids rather than using an additional variable.

Link: https://lkml.kernel.org/r/20220527000003.355812-4-tyhicks@linux.microsoft.com
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>

fs/9p/fid.c

@@ -150,7 +150,7 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
 {
 	struct dentry *ds;
 	const unsigned char **wnames, *uname;
-	int i, n, l, clone, access;
+	int i, n, l, access;
 	struct v9fs_session_info *v9ses;
 	struct p9_fid *fid, *root_fid, *old_fid;
 
@@ -214,7 +214,6 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
 	}
 	fid = root_fid;
 	old_fid = root_fid;
-	clone = 1;
 	i = 0;
 	while (i < n) {
 		l = min(n - i, P9_MAXWELEM);
@@ -222,7 +221,8 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
 		 * We need to hold rename lock when doing a multipath
 		 * walk to ensure none of the patch component change
 		 */
-		fid = p9_client_walk(old_fid, l, &wnames[i], clone);
+		fid = p9_client_walk(old_fid, l, &wnames[i],
+				     old_fid == root_fid /* clone */);
 		/* non-cloning walk will return the same fid */
 		if (fid != old_fid) {
 			p9_client_clunk(old_fid);
@@ -233,7 +233,6 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
 			goto err_out;
 		}
 		i += l;
-		clone = 0;
 	}
 	kfree(wnames);
 fid_out: