2 files changed, 24 insertions, 9 deletions

diff --git a/fs/dcache.c b/fs/dcache.c
index 2a4ce7dc2306..5699d4c027cb 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1454,9 +1454,7 @@ static struct dentry *__d_instantiate_unique(struct dentry *entry,
                         continue;
                 if (alias->d_parent != entry->d_parent)
                         continue;
-                if (qstr->len != len)
-                        continue;
-                if (memcmp(qstr->name, name, len))
+                if (dentry_cmp(qstr->name, qstr->len, name, len))
                         continue;
                 __dget(alias);
                 return alias;
@@ -1810,9 +1808,7 @@ seqretry:
                                                 tlen, tname, name))
                                 continue;
                 } else {
-                        if (tlen != len)
-                                continue;
-                        if (memcmp(tname, str, tlen))
+                        if (dentry_cmp(tname, tlen, str, len))
                                 continue;
                 }
                 /*
@@ -1925,9 +1921,7 @@ struct dentry *__d_lookup(struct dentry *parent, struct qstr *name)
                                                 tlen, tname, name))
                                 goto next;
                 } else {
-                        if (tlen != len)
-                                goto next;
-                        if (memcmp(tname, str, tlen))
+                        if (dentry_cmp(tname, tlen, str, len))
                                 goto next;
                 }
 
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index c0a2ca97c72f..bd07758943e0 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -47,6 +47,27 @@ struct dentry_stat_t {
 };
 extern struct dentry_stat_t dentry_stat;
 
+/*
+ * 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)
+{
+        int ret;
+        if (scount != tcount)
+                return 1;
+        do {
+                ret = (*cs != *ct);
+                if (ret)
+                        break;
+                cs++;
+                ct++;
+                tcount--;
+        } while (tcount);
+        return ret;
+}
+
 /* Name hashing routines. Initial hash value */
 /* Hash courtesy of the R5 hash in reiserfs modulo sign bits */
 #define init_name_hash()                0