[15/24] link_path_walk: final preparations to killing recursion

Commit Message

Al Viro April 20, 2015, 6:12 p.m. UTC

From: Al Viro <[e-mail]>

reduce the number of returns in there - turn all places
where it returns zero into goto OK and places where it
returns non-zero into goto Err.  The only non-trivial
detail is that all breaks in the loop are guaranteed
to be with non-zero err.

Signed-off-by: Al Viro <[e-mail]>
---
 fs/namei.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

Patch

diff --git a/fs/namei.c b/fs/namei.c
index 9cef3c0..6d79e00 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1773,7 +1773,7 @@  static int link_path_walk(const char *name, struct nameidata *nd)
 	while (*name=='/')
 		name++;
 	if (!*name)
-		return 0;
+		goto OK;
 
 	/* At this point we know we have a real path component. */
 	for(;;) {
@@ -1816,7 +1816,7 @@  static int link_path_walk(const char *name, struct nameidata *nd)
 
 		name += hashlen_len(hash_len);
 		if (!*name)
-			return 0;
+			goto OK;
 		/*
 		 * If it wasn't NUL, we know it was '/'. Skip that
 		 * slash, and continue until no more slashes.
@@ -1825,12 +1825,12 @@  static int link_path_walk(const char *name, struct nameidata *nd)
 			name++;
 		} while (unlikely(*name == '/'));
 		if (!*name)
-			return 0;
+			goto OK;
 
 		err = walk_component(nd, &next, LOOKUP_FOLLOW);
 Walked:
 		if (err < 0)
-			return err;
+			goto Err;
 
 		if (err) {
 			struct path link;
@@ -1840,7 +1840,8 @@  Walked:
 			if (unlikely(nd->link_count >= MAX_NESTED_LINKS)) {
 				path_put_conditional(&next, nd);
 				path_put(&nd->path);
-				return -ELOOP;
+				err = -ELOOP;
+				goto Err;
 			}
 			BUG_ON(nd->depth >= MAX_NESTED_LINKS);
 
@@ -1854,7 +1855,7 @@  Walked:
 				err = PTR_ERR(s);
 				nd->link_count--;
 				nd->depth--;
-				return err;
+				goto Err;
 			}
 			err = 0;
 			if (unlikely(!s)) {
@@ -1877,7 +1878,7 @@  Walked:
 					put_link(nd, &link, cookie);
 					nd->link_count--;
 					nd->depth--;
-					return err;
+					goto Err;
 				} else {
 					err = walk_component(nd, &next, LOOKUP_FOLLOW);
 					put_link(nd, &link, cookie);
@@ -1893,7 +1894,10 @@  Walked:
 		}
 	}
 	terminate_walk(nd);
+Err:
 	return err;
+OK:
+	return 0;
 }
 
 static int path_init(int dfd, const struct filename *name, unsigned int flags,