/* SPDX-License-Identifier: GPL-2.0 */

  /*
    File: linux/xattr.h
  
    Extended attributes handling.
  
    Copyright (C) 2001 by Andreas Gruenbacher <a.gruenbacher@computer.org>
    Copyright (c) 2001-2002 Silicon Graphics, Inc.  All Rights Reserved.
    Copyright (c) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
  */
  #ifndef _LINUX_XATTR_H
  #define _LINUX_XATTR_H

  #include <linux/slab.h>

  #include <linux/types.h>

  #include <linux/spinlock.h>

  #include <linux/mm.h>

  #include <uapi/linux/xattr.h>

  struct inode;
  struct dentry;

  /*
   * struct xattr_handler: When @name is set, match attributes with exactly that
   * name.  When @prefix is set instead, match attributes with that prefix and
   * with a non-empty suffix.
   */

  struct xattr_handler {

  	const char *name;

  	const char *prefix;

  	int flags;      /* fs private flags */

  	bool (*list)(struct dentry *dentry);

  	int (*get)(const struct xattr_handler *handler, struct dentry *dentry,

  		   struct inode *inode, const char *name, void *buffer,

  		   size_t size, int flags);
  	int (*set)(const struct xattr_handler *handler, struct dentry *dentry,

  		   struct inode *inode, const char *name, const void *buffer,
  		   size_t size, int flags);

  };

  const char *xattr_full_name(const struct xattr_handler *, const char *);

  struct xattr {

  	const char *name;

  	void *value;
  	size_t value_len;
  };

  ssize_t __vfs_getxattr(struct dentry *dentry, struct inode *inode,
  		       const char *name, void *buffer, size_t size, int flags);

  ssize_t vfs_getxattr(struct dentry *, const char *, void *, size_t);

  ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size);

  int __vfs_setxattr(struct dentry *, struct inode *, const char *, const void *, size_t, int);

  int __vfs_setxattr_noperm(struct dentry *, const char *, const void *, size_t, int);

  int __vfs_setxattr_locked(struct dentry *, const char *, const void *, size_t, int, struct inode **);

  int vfs_setxattr(struct dentry *, const char *, const void *, size_t, int);

  int __vfs_removexattr(struct dentry *, const char *);

  int __vfs_removexattr_locked(struct dentry *, const char *, struct inode **);

  int vfs_removexattr(struct dentry *, const char *);

  ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size);

  ssize_t vfs_getxattr_alloc(struct dentry *dentry, const char *name,
  			   char **xattr_value, size_t size, gfp_t flags);

  int xattr_supported_namespace(struct inode *inode, const char *prefix);

  static inline const char *xattr_prefix(const struct xattr_handler *handler)
  {
  	return handler->prefix ?: handler->name;
  }

  struct simple_xattrs {
  	struct list_head head;
  	spinlock_t lock;
  };
  
  struct simple_xattr {
  	struct list_head list;
  	char *name;
  	size_t size;

  	char value[];

  };
  
  /*
   * initialize the simple_xattrs structure
   */
  static inline void simple_xattrs_init(struct simple_xattrs *xattrs)
  {
  	INIT_LIST_HEAD(&xattrs->head);
  	spin_lock_init(&xattrs->lock);
  }
  
  /*
   * free all the xattrs
   */
  static inline void simple_xattrs_free(struct simple_xattrs *xattrs)
  {
  	struct simple_xattr *xattr, *node;
  
  	list_for_each_entry_safe(xattr, node, &xattrs->head, list) {
  		kfree(xattr->name);

  		kvfree(xattr);

  	}
  }
  
  struct simple_xattr *simple_xattr_alloc(const void *value, size_t size);
  int simple_xattr_get(struct simple_xattrs *xattrs, const char *name,
  		     void *buffer, size_t size);
  int simple_xattr_set(struct simple_xattrs *xattrs, const char *name,

  		     const void *value, size_t size, int flags,
  		     ssize_t *removed_size);

  ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs, char *buffer,
  			  size_t size);

  void simple_xattr_list_add(struct simple_xattrs *xattrs,
  			   struct simple_xattr *new_xattr);

  #endif	/* _LINUX_XATTR_H */