From 917ea166f4672ec085f2cccc135c7c0eec72282c Mon Sep 17 00:00:00 2001 From: George Spelvin Date: Fri, 20 May 2016 13:31:33 -0400 Subject: [PATCH] : 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 Tested-by: J. Bruce Fields Acked-by: J. Bruce Fields Cc: Jeff Layton Cc: linux-nfs@vger.kernel.org --- include/linux/sunrpc/svcauth.h | 40 ++++++++-------------------------- 1 file changed, 9 insertions(+), 31 deletions(-) diff --git a/include/linux/sunrpc/svcauth.h b/include/linux/sunrpc/svcauth.h index c00f53a4ccdd..91d5a5d6f52b 100644 --- a/include/linux/sunrpc/svcauth.h +++ b/include/linux/sunrpc/svcauth.h @@ -16,6 +16,7 @@ #include #include #include +#include #include 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 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__ */ -- 2.20.1