[PATCH 06/14] d_path: don't bother with return value of prepend()

Al Viro
2021-05-19T00:51:24Z

Only simple_dname() checks it, and there we can simply do those
calls and check for overflow (by looking of negative buflen)
in the end.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
fs/d_path.c | 20 +++++++++-----------
1 file changed, 9 insertions(+), 11 deletions(-)

diff --git a/fs/d_path.c b/fs/d_path.c
index 311d43287572..72b8087aaf9c 100644
--- a/fs/d_path.c
+++ b/fs/d_path.c
@@ -8,14 +8,13 @@
#include <linux/prefetch.h>
#include "mount.h"

-static int prepend(char **buffer, int *buflen, const char *str, int namelen)
+static void prepend(char **buffer, int *buflen, const char *str, int namelen)
{
*buflen -= namelen;
- if (*buflen < 0)
- return -ENAMETOOLONG;
- *buffer -= namelen;
- memcpy(*buffer, str, namelen);
- return 0;
+ if (likely(*buflen >= 0)) {
+ *buffer -= namelen;
+ memcpy(*buffer, str, namelen);
+ }
}

/**
@@ -298,11 +297,10 @@ char *simple_dname(struct dentry *dentry, char *buffer, int buflen)
{
char *end = buffer + buflen;
/* these dentries are never renamed, so d_lock is not needed */
- if (prepend(&end, &buflen, " (deleted)", 11) ||
- prepend(&end, &buflen, dentry->d_name.name, dentry->d_name.len) ||
- prepend(&end, &buflen, "/", 1))
- end = ERR_PTR(-ENAMETOOLONG);
- return end;
+ prepend(&end, &buflen, " (deleted)", 11);
+ prepend(&end, &buflen, dentry->d_name.name, dentry->d_name.len);
+ prepend(&end, &buflen, "/", 1);
+ return buflen >= 0 ? end : ERR_PTR(-ENAMETOOLONG);
}

/*
--
2.11.0