link_path_walk: final preparations to killing recursion

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 <viro@zeniv.linux.org.uk>

diff --git a/fs/namei.c b/fs/namei.c
index 9f45d339cf4566f2e4ee038e4e3fcff402df8555..b469ce26ff74f29289f092e44e44d69a6f4450f5 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1716,7 +1716,7 @@ 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(;;) {
@@ -1759,7 +1759,7 @@ 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.
@@ -1768,12 +1768,12 @@ 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, LOOKUP_FOLLOW);
 Walked:
                if (err < 0)
-                       return err;
+                       goto Err;
 
                if (err) {
                        struct path link;
@@ -1783,7 +1783,8 @@ Walked:
                        if (unlikely(current->link_count >= MAX_NESTED_LINKS)) {
                                path_put_conditional(&nd->link, nd);
                                path_put(&nd->path);
-                               return -ELOOP;
+                               err = -ELOOP;
+                               goto Err;
                        }
                        BUG_ON(nd->depth >= MAX_NESTED_LINKS);
 
@@ -1797,7 +1798,7 @@ Walked:
                                err = PTR_ERR(s);
                                current->link_count--;
                                nd->depth--;
-                               return err;
+                               goto Err;
                        }
                        err = 0;
                        if (unlikely(!s)) {
@@ -1820,7 +1821,7 @@ Walked:
                                        put_link(nd, &link, cookie);
                                        current->link_count--;
                                        nd->depth--;
-                                       return err;
+                                       goto Err;
                                } else {
                                        err = walk_component(nd, LOOKUP_FOLLOW);
                                        put_link(nd, &link, cookie);
@@ -1836,7 +1837,10 @@ Walked:
                }
        }
        terminate_walk(nd);
+Err:
        return err;
+OK:
+       return 0;
 }
 
 static int path_init(int dfd, const struct filename *name, unsigned int flags,