useful constants: struct qstr for ".."

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/dcache.c

@@ -84,6 +84,8 @@ const struct qstr empty_name = QSTR_INIT("", 0);
 EXPORT_SYMBOL(empty_name);
 const struct qstr slash_name = QSTR_INIT("/", 1);
 EXPORT_SYMBOL(slash_name);
+const struct qstr dotdot_name = QSTR_INIT("..", 2);
+EXPORT_SYMBOL(dotdot_name);
 
 /*
  * This is the single most critical data structure when it comes

fs/ext2/namei.c

@@ -81,11 +81,10 @@ static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, uns
 
 struct dentry *ext2_get_parent(struct dentry *child)
 {
-	struct qstr dotdot = QSTR_INIT("..", 2);
 	ino_t ino;
 	int res;
 
-	res = ext2_inode_by_name(d_inode(child), &dotdot, &ino);
+	res = ext2_inode_by_name(d_inode(child), &dotdot_name, &ino);
 	if (res)
 		return ERR_PTR(res);
 

fs/ext4/namei.c

@@ -1739,11 +1739,10 @@ static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsi
 struct dentry *ext4_get_parent(struct dentry *child)
 {
 	__u32 ino;
-	static const struct qstr dotdot = QSTR_INIT("..", 2);
 	struct ext4_dir_entry_2 * de;
 	struct buffer_head *bh;
 
-	bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL);
+	bh = ext4_find_entry(d_inode(child), &dotdot_name, &de, NULL);
 	if (IS_ERR(bh))
 		return ERR_CAST(bh);
 	if (!bh)

fs/f2fs/dir.c

@@ -449,9 +449,7 @@ struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
 
 struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)
 {
-	struct qstr dotdot = QSTR_INIT("..", 2);
-
-	return f2fs_find_entry(dir, &dotdot, p);
+	return f2fs_find_entry(dir, &dotdot_name, p);
 }
 
 ino_t f2fs_inode_by_name(struct inode *dir, const struct qstr *qstr,

fs/f2fs/namei.c

@@ -416,9 +416,8 @@ static int f2fs_link(struct dentry *old_dentry, struct inode *dir,
 
 struct dentry *f2fs_get_parent(struct dentry *child)
 {
-	struct qstr dotdot = QSTR_INIT("..", 2);
 	struct page *page;
-	unsigned long ino = f2fs_inode_by_name(d_inode(child), &dotdot, &page);
+	unsigned long ino = f2fs_inode_by_name(d_inode(child), &dotdot_name, &page);
 	if (!ino) {
 		if (IS_ERR(page))
 			return ERR_CAST(page);

fs/fuse/inode.c

@@ -872,14 +872,13 @@ static struct dentry *fuse_get_parent(struct dentry *child)
 	struct inode *inode;
 	struct dentry *parent;
 	struct fuse_entry_out outarg;
-	const struct qstr name = QSTR_INIT("..", 2);
 	int err;
 
 	if (!fc->export_support)
 		return ERR_PTR(-ESTALE);
 
 	err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode),
-			       &name, &outarg, &inode);
+			       &dotdot_name, &outarg, &inode);
 	if (err) {
 		if (err == -ENOENT)
 			return ERR_PTR(-ESTALE);

fs/nilfs2/namei.c

@@ -440,10 +440,9 @@ static struct dentry *nilfs_get_parent(struct dentry *child)
 {
 	unsigned long ino;
 	struct inode *inode;
-	struct qstr dotdot = QSTR_INIT("..", 2);
 	struct nilfs_root *root;
 
-	ino = nilfs_inode_by_name(d_inode(child), &dotdot);
+	ino = nilfs_inode_by_name(d_inode(child), &dotdot_name);
 	if (!ino)
 		return ERR_PTR(-ENOENT);
 

fs/udf/namei.c

@@ -1215,11 +1215,10 @@ static struct dentry *udf_get_parent(struct dentry *child)
 {
 	struct kernel_lb_addr tloc;
 	struct inode *inode = NULL;
-	struct qstr dotdot = QSTR_INIT("..", 2);
 	struct fileIdentDesc cfi;
 	struct udf_fileident_bh fibh;
 
-	if (!udf_find_entry(d_inode(child), &dotdot, &fibh, &cfi))
+	if (!udf_find_entry(d_inode(child), &dotdot_name, &fibh, &cfi))
 		return ERR_PTR(-EACCES);
 
 	if (fibh.sbh != fibh.ebh)

fs/ufs/super.c

@@ -128,10 +128,9 @@ static struct dentry *ufs_fh_to_parent(struct super_block *sb, struct fid *fid,
 
 static struct dentry *ufs_get_parent(struct dentry *child)
 {
-	struct qstr dot_dot = QSTR_INIT("..", 2);
 	ino_t ino;
 
-	ino = ufs_inode_by_name(d_inode(child), &dot_dot);
+	ino = ufs_inode_by_name(d_inode(child), &dotdot_name);
 	if (!ino)
 		return ERR_PTR(-ENOENT);
 	return d_obtain_alias(ufs_iget(child->d_sb, ino));

include/linux/dcache.h

@@ -59,6 +59,7 @@ struct qstr {
 
 extern const struct qstr empty_name;
 extern const struct qstr slash_name;
+extern const struct qstr dotdot_name;
 
 struct dentry_stat_t {
 	long nr_dentry;