vfs: make the string hashes salt the hash

We always mixed in the parent pointer into the dentry name hash, but we
did it late at lookup time.  It turns out that we can simplify that
lookup-time action by salting the hash with the parent pointer early
instead of late.

A few other users of our string hashes also wanted to mix in their own
pointers into the hash, and those are updated to use the same mechanism.

Hash users that don't have any particular initial salt can just use the
NULL pointer as a no-salt.

Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/include/linux/sunrpc/svcauth.h b/include/linux/sunrpc/svcauth.h
index 91d5a5d6f52b..d03932055328 100644
--- a/include/linux/sunrpc/svcauth.h
+++ b/include/linux/sunrpc/svcauth.h
@@ -172,12 +172,12 @@ extern void unix_gid_cache_destroy(struct net *net);
  */
 static inline unsigned long hash_str(char const *name, int bits)
 {
-	return hashlen_hash(hashlen_string(name)) >> (32 - bits);
+	return hashlen_hash(hashlen_string(NULL, name)) >> (32 - bits);
 }
 
 static inline unsigned long hash_mem(char const *buf, int length, int bits)
 {
-	return full_name_hash(buf, length) >> (32 - bits);
+	return full_name_hash(NULL, buf, length) >> (32 - bits);
 }
 
 #endif /* __KERNEL__ */