Merge tag 'char-misc-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh...

[cascardo/linux.git] / fs / dcache.c

diff --git a/fs/dcache.c b/fs/dcache.c
index 138be96..11828de 100644 (file)
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -105,10 +105,10 @@ static unsigned int d_hash_shift __read_mostly;
 static struct hlist_bl_head *dentry_hashtable __read_mostly;
 
 static inline struct hlist_bl_head *d_hash(const struct dentry *parent,
-                                       unsigned long hash)
+                                       unsigned int hash)
 {
-       hash += ((unsigned long) parent ^ GOLDEN_RATIO_PRIME) / L1_CACHE_BYTES;
-       hash = hash ^ ((hash ^ GOLDEN_RATIO_PRIME) >> D_HASHBITS);
+       hash += (unsigned long) parent / L1_CACHE_BYTES;
+       hash = hash + (hash >> D_HASHBITS);
        return dentry_hashtable + (hash & D_HASHMASK);
 }
 
@@ -137,6 +137,49 @@ int proc_nr_dentry(ctl_table *table, int write, void __user *buffer,
 }
 #endif
 
+/*
+ * Compare 2 name strings, return 0 if they match, otherwise non-zero.
+ * The strings are both count bytes long, and count is non-zero.
+ */
+static inline int dentry_cmp(const unsigned char *cs, size_t scount,
+                               const unsigned char *ct, size_t tcount)
+{
+#ifdef CONFIG_DCACHE_WORD_ACCESS
+       unsigned long a,b,mask;
+
+       if (unlikely(scount != tcount))
+               return 1;
+
+       for (;;) {
+               a = *(unsigned long *)cs;
+               b = *(unsigned long *)ct;
+               if (tcount < sizeof(unsigned long))
+                       break;
+               if (unlikely(a != b))
+                       return 1;
+               cs += sizeof(unsigned long);
+               ct += sizeof(unsigned long);
+               tcount -= sizeof(unsigned long);
+               if (!tcount)
+                       return 0;
+       }
+       mask = ~(~0ul << tcount*8);
+       return unlikely(!!((a ^ b) & mask));
+#else
+       if (scount != tcount)
+               return 1;
+
+       do {
+               if (*cs != *ct)
+                       return 1;
+               cs++;
+               ct++;
+               tcount--;
+       } while (tcount);
+       return 0;
+#endif
+}
+
 static void __d_free(struct rcu_head *head)
 {
        struct dentry *dentry = container_of(head, struct dentry, d_u.d_rcu);