[PATCH 03/10] <linux/sunrpc/svcauth.h>: Define hash_str() in terms of hash_string()

From: George Spelvin
Date: Wed May 25 2016 - 03:26:36 EST


Finally, the first use of previous two patches: Eliminate the
separate ad-hoc string hash functions in the sunrpc code.

This also eliminates the only caller of hash_long which asks for
more than 32 bits of output.

sunrpc guys: Is it okay if I send this to Linus directly?

Signed-off-by: George Spelvin <linux@xxxxxxxxxxxxxxxxxxx>
Cc: "J. Bruce Fields" <bfields@xxxxxxxxxxxx>
Cc: Jeff Layton <jlayton@xxxxxxxxxxxxxxx>
Cc: linux-nfs@xxxxxxxxxxxxxxx
---
include/linux/sunrpc/svcauth.h | 36 +++++-------------------------------
1 file changed, 5 insertions(+), 31 deletions(-)

diff --git a/include/linux/sunrpc/svcauth.h b/include/linux/sunrpc/svcauth.h
index c00f53a4..ef2b2552 100644
--- a/include/linux/sunrpc/svcauth.h
+++ b/include/linux/sunrpc/svcauth.h
@@ -16,6 +16,7 @@
#include <linux/sunrpc/cache.h>
#include <linux/sunrpc/gss_api.h>
#include <linux/hash.h>
+#include <linux/stringhash.h>
#include <linux/cred.h>

struct svc_cred {
@@ -165,41 +166,14 @@ extern int svcauth_unix_set_client(struct svc_rqst *rqstp);
extern int unix_gid_cache_create(struct net *net);
extern void unix_gid_cache_destroy(struct net *net);

-static inline unsigned long hash_str(char *name, int bits)
+static inline unsigned long hash_str(char const *name, int bits)
{
- unsigned long hash = 0;
- unsigned long l = 0;
- int len = 0;
- unsigned char c;
- do {
- if (unlikely(!(c = *name++))) {
- c = (char)len; len = -1;
- }
- l = (l << 8) | c;
- len++;
- if ((len & (BITS_PER_LONG/8-1))==0)
- hash = hash_long(hash^l, BITS_PER_LONG);
- } while (len);
- return hash >> (BITS_PER_LONG - bits);
+ return hash_32(hashlen_hash(hash_string(name)), bits);
}

-static inline unsigned long hash_mem(char *buf, int length, int bits)
+static inline unsigned long hash_mem(char const *buf, int length, int bits)
{
- unsigned long hash = 0;
- unsigned long l = 0;
- int len = 0;
- unsigned char c;
- do {
- if (len == length) {
- c = (char)len; len = -1;
- } else
- c = *buf++;
- l = (l << 8) | c;
- len++;
- if ((len & (BITS_PER_LONG/8-1))==0)
- hash = hash_long(hash^l, BITS_PER_LONG);
- } while (len);
- return hash >> (BITS_PER_LONG - bits);
+ return hash_32(full_name_hash(buf, length), bits);
}

#endif /* __KERNEL__ */
--
2.8.1