vfs: uninline full_name_hash()

.. and also use it in lookup_one_len() rather than open-coding it.

There aren't any performance-critical users, so inlining it is silly.
But it wouldn't matter if it wasn't for the fact that the word-at-a-time
dentry name patches want to conditionally replace the function, and
uninlining it sets the stage for that.

So again, this is a preparatory patch that doesn't change any semantics,
and only prepares for a much cleaner and testable word-at-a-time dentry
name accessor patch.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/namei.c b/fs/namei.c
index a780ea5..ec72fa1 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1374,6 +1374,14 @@ static inline int can_lookup(struct inode *inode)
        return 1;
 }
 
+unsigned int full_name_hash(const unsigned char *name, unsigned int len)
+{
+       unsigned long hash = init_name_hash();
+       while (len--)
+               hash = partial_name_hash(*name++, hash);
+       return end_name_hash(hash);
+}
+
 /*
  * Name resolution.
  * This is the basic name resolution function, turning a pathname into
@@ -1775,24 +1783,21 @@ static struct dentry *lookup_hash(struct nameidata *nd)
 struct dentry *lookup_one_len(const char *name, struct dentry *base, int len)
 {
        struct qstr this;
-       unsigned long hash;
        unsigned int c;
 
        WARN_ON_ONCE(!mutex_is_locked(&base->d_inode->i_mutex));
 
        this.name = name;
        this.len = len;
+       this.hash = full_name_hash(name, len);
        if (!len)
                return ERR_PTR(-EACCES);
 
-       hash = init_name_hash();
        while (len--) {
                c = *(const unsigned char *)name++;
                if (c == '/' || c == '\0')
                        return ERR_PTR(-EACCES);
-               hash = partial_name_hash(c, hash);
        }
-       this.hash = end_name_hash(hash);
        /*
         * See if the low-level filesystem might want
         * to use its own hash..

diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index 61b2426..f1c7eb8 100644 (file)
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -89,14 +89,7 @@ static inline unsigned long end_name_hash(unsigned long hash)
 }
 
 /* Compute the hash for a name string. */
-static inline unsigned int
-full_name_hash(const unsigned char *name, unsigned int len)
-{
-       unsigned long hash = init_name_hash();
-       while (len--)
-               hash = partial_name_hash(*name++, hash);
-       return end_name_hash(hash);
-}
+extern unsigned int full_name_hash(const unsigned char *, unsigned int);
 
 /*
  * Try to keep struct dentry aligned on 64 byte cachelines (this will