libfs: Export generic_ci_ dentry functions

Export generic_ci_ dentry functions so they can be used by
case-insensitive filesystems that need something more custom than the
default one set by `struct generic_ci_dentry_ops`.

Reviewed-by: Gabriel Krisman Bertazi <gabriel@krisman.be>
Signed-off-by: André Almeida <andrealmeid@igalia.com>
Link: https://lore.kernel.org/r/20241021-tonyk-tmpfs-v8-5-f443d5814194@igalia.com
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: andrealmeid

fs/libfs.c

@@ -1791,8 +1791,8 @@ bool is_empty_dir_inode(struct inode *inode)
  *
  * Return: 0 if names match, 1 if mismatch, or -ERRNO
  */
-static int generic_ci_d_compare(const struct dentry *dentry, unsigned int len,
-				const char *str, const struct qstr *name)
+int generic_ci_d_compare(const struct dentry *dentry, unsigned int len,
+			 const char *str, const struct qstr *name)
 {
 	const struct dentry *parent;
 	const struct inode *dir;
@@ -1835,6 +1835,7 @@ static int generic_ci_d_compare(const struct dentry *dentry, unsigned int len,
 
 	return utf8_strncasecmp(dentry->d_sb->s_encoding, name, &qstr);
 }
+EXPORT_SYMBOL(generic_ci_d_compare);
 
 /**
  * generic_ci_d_hash - generic d_hash implementation for casefolding filesystems
@@ -1843,7 +1844,7 @@ static int generic_ci_d_compare(const struct dentry *dentry, unsigned int len,
  *
  * Return: 0 if hash was successful or unchanged, and -EINVAL on error
  */
-static int generic_ci_d_hash(const struct dentry *dentry, struct qstr *str)
+int generic_ci_d_hash(const struct dentry *dentry, struct qstr *str)
 {
 	const struct inode *dir = READ_ONCE(dentry->d_inode);
 	struct super_block *sb = dentry->d_sb;
@@ -1858,6 +1859,7 @@ static int generic_ci_d_hash(const struct dentry *dentry, struct qstr *str)
 		return -EINVAL;
 	return 0;
 }
+EXPORT_SYMBOL(generic_ci_d_hash);
 
 static const struct dentry_operations generic_ci_dentry_ops = {
 	.d_hash = generic_ci_d_hash,

include/linux/fs.h

@@ -3458,6 +3458,10 @@ extern int generic_ci_match(const struct inode *parent,
 			    const u8 *de_name, u32 de_name_len);
 
 #if IS_ENABLED(CONFIG_UNICODE)
+int generic_ci_d_hash(const struct dentry *dentry, struct qstr *str);
+int generic_ci_d_compare(const struct dentry *dentry, unsigned int len,
+			 const char *str, const struct qstr *name);
+
 /**
  * generic_ci_validate_strict_name - Check if a given name is suitable
  * for a directory