ext4: improve some code in rb tree part of dir.c

* remove unnecessary code in free_rb_tree_fname

* rename free_rb_tree_fname to ext4_htree_create_dir_info
  since it and ext4_htree_free_dir_info are a pair

* replace kmalloc with kzalloc in ext4_htree_free_dir_info

All these make the code more readable and simple.
PS: this patch is also suitable for ext3.

Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index 2bf0331ea1946303f0caedf360dce0cb9dc38445..5ed5108766c16c7e42eea73c413f450f25b5aa22 100644 (file)
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -272,7 +272,7 @@ static void free_rb_tree_fname(struct rb_root *root)
 
        while (n) {
                /* Do the node's children first */
-               if ((n)->rb_left) {
+               if (n->rb_left) {
                        n = n->rb_left;
                        continue;
                }
@@ -301,24 +301,18 @@ static void free_rb_tree_fname(struct rb_root *root)
                        parent->rb_right = NULL;
                n = parent;
        }
-       root->rb_node = NULL;
 }
 
 
-static struct dir_private_info *create_dir_info(loff_t pos)
+static struct dir_private_info *ext4_htree_create_dir_info(loff_t pos)
 {
        struct dir_private_info *p;
 
-       p = kmalloc(sizeof(struct dir_private_info), GFP_KERNEL);
+       p = kzalloc(sizeof(struct dir_private_info), GFP_KERNEL);
        if (!p)
                return NULL;
-       p->root.rb_node = NULL;
-       p->curr_node = NULL;
-       p->extra_fname = NULL;
-       p->last_pos = 0;
        p->curr_hash = pos2maj_hash(pos);
        p->curr_minor_hash = pos2min_hash(pos);
-       p->next_hash = 0;
        return p;
 }
 
@@ -433,7 +427,7 @@ static int ext4_dx_readdir(struct file * filp,
        int     ret;
 
        if (!info) {
-               info = create_dir_info(filp->f_pos);
+               info = ext4_htree_create_dir_info(filp->f_pos);
                if (!info)
                        return -ENOMEM;
                filp->private_data = info;