<linux/sunrpc/svcauth.h>: Define hash_str() in terms of hashlen_string()

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

Now hash_str() is a wrapper around hash_string(), and hash_mem() is
likewise a wrapper around full_name_hash().

Note that sunrpc code *does* call hash_mem() with a zero length, which
is why the previous patch needed to handle that in full_name_hash().
(Thanks, Bruce, for finding that!)

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

The comment about the quality of hashlen_string() and full_name_hash()
is jumping the gun by a few patches; they aren't very impressive now,
but will be improved greatly later in the series.

Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: linux-nfs@vger.kernel.org
This commit is contained in:
George Spelvin 2016-05-20 13:31:33 -04:00
parent fcfd2fbf22
commit 917ea166f4

View File

@ -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 +166,18 @@ 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)
/*
* The <stringhash.h> functions are good enough that we don't need to
* use hash_32() on them; just extracting the high bits is enough.
*/
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 hashlen_hash(hashlen_string(name)) >> (32 - 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 full_name_hash(buf, length) >> (32 - bits);
}
#endif /* __KERNEL__ */