1 files changed, 132 insertions, 0 deletions
diff --git a/include/linux/xattr.h b/include/linux/xattr.h
new file mode 100644
index 000000000..d20051865
--- /dev/null
+++ b/include/linux/xattr.h
@@ -0,0 +1,132 @@
+/* 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 <linux/user_namespace.h>
+#include <uapi/linux/xattr.h>
+
+struct inode;
+struct dentry;
+
+static inline bool is_posix_acl_xattr(const char *name)
+{
+	return (strcmp(name, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
+	       (strcmp(name, XATTR_NAME_POSIX_ACL_DEFAULT) == 0);
+}
+
+/*
+ * 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 *, struct dentry *dentry,
+		   struct inode *inode, const char *name, void *buffer,
+		   size_t size);
+	int (*set)(const struct xattr_handler *,
+		   struct mnt_idmap *idmap, struct dentry *dentry,
+		   struct inode *inode, const char *name, const void *buffer,
+		   size_t size, int flags);
+};
+
+/**
+ * xattr_handler_can_list - check whether xattr can be listed
+ * @handler: handler for this type of xattr
+ * @dentry: dentry whose inode xattr to list
+ *
+ * Determine whether the xattr associated with @dentry can be listed given
+ * @handler.
+ *
+ * Return: true if xattr can be listed, false if not.
+ */
+static inline bool xattr_handler_can_list(const struct xattr_handler *handler,
+					  struct dentry *dentry)
+{
+	return handler && (!handler->list || handler->list(dentry));
+}
+
+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 *, struct inode *, const char *, void *, size_t);
+ssize_t vfs_getxattr(struct mnt_idmap *, struct dentry *, const char *,
+		     void *, size_t);
+ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size);
+int __vfs_setxattr(struct mnt_idmap *, struct dentry *, struct inode *,
+		   const char *, const void *, size_t, int);
+int __vfs_setxattr_noperm(struct mnt_idmap *, struct dentry *,
+			  const char *, const void *, size_t, int);
+int __vfs_setxattr_locked(struct mnt_idmap *, struct dentry *,
+			  const char *, const void *, size_t, int,
+			  struct inode **);
+int vfs_setxattr(struct mnt_idmap *, struct dentry *, const char *,
+		 const void *, size_t, int);
+int __vfs_removexattr(struct mnt_idmap *, struct dentry *, const char *);
+int __vfs_removexattr_locked(struct mnt_idmap *, struct dentry *,
+			     const char *, struct inode **);
+int vfs_removexattr(struct mnt_idmap *, struct dentry *, const char *);
+
+ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size);
+int vfs_getxattr_alloc(struct mnt_idmap *idmap,
+		       struct dentry *dentry, const char *name,
+		       char **xattr_value, size_t size, gfp_t flags);
+
+int xattr_supports_user_prefix(struct inode *inode);
+
+static inline const char *xattr_prefix(const struct xattr_handler *handler)
+{
+	return handler->prefix ?: handler->name;
+}
+
+struct simple_xattrs {
+	struct rb_root rb_root;
+	rwlock_t lock;
+};
+
+struct simple_xattr {
+	struct rb_node rb_node;
+	char *name;
+	size_t size;
+	char value[];
+};
+
+void simple_xattrs_init(struct simple_xattrs *xattrs);
+void simple_xattrs_free(struct simple_xattrs *xattrs, size_t *freed_space);
+size_t simple_xattr_space(const char *name, size_t size);
+struct simple_xattr *simple_xattr_alloc(const void *value, size_t size);
+void simple_xattr_free(struct simple_xattr *xattr);
+int simple_xattr_get(struct simple_xattrs *xattrs, const char *name,
+		     void *buffer, size_t size);
+struct simple_xattr *simple_xattr_set(struct simple_xattrs *xattrs,
+				      const char *name, const void *value,
+				      size_t size, int flags);
+ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs,
+			  char *buffer, size_t size);
+void simple_xattr_add(struct simple_xattrs *xattrs,
+		      struct simple_xattr *new_xattr);
+int xattr_list_one(char **buffer, ssize_t *remaining_size, const char *name);
+
+#endif	/* _LINUX_XATTR_H */