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 9f45d33..b469ce2 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1716,7 +1716,7 @@
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 @@
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 @@
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 @@
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 @@
err = PTR_ERR(s);
current->link_count--;
nd->depth--;
- return err;
+ goto Err;
}
err = 0;
if (unlikely(!s)) {
@@ -1820,7 +1821,7 @@
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 @@
}
}
terminate_walk(nd);
+Err:
return err;
+OK:
+ return 0;
}
static int path_init(int dfd, const struct filename *name, unsigned int flags,