1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 * fs/kernfs/kernfs-internal.h - kernfs internal header file
  4 *
  5 * Copyright (c) 2001-3 Patrick Mochel
  6 * Copyright (c) 2007 SUSE Linux Products GmbH
  7 * Copyright (c) 2007, 2013 Tejun Heo <teheo@suse.de>
  8 */
  9
 10#ifndef __KERNFS_INTERNAL_H
 11#define __KERNFS_INTERNAL_H
 12
 13#include <linux/lockdep.h>
 14#include <linux/fs.h>
 15#include <linux/mutex.h>
 16#include <linux/xattr.h>
 17
 18#include <linux/kernfs.h>
 19#include <linux/fs_context.h>
 20
 21struct kernfs_iattrs {
 22	kuid_t			ia_uid;
 23	kgid_t			ia_gid;
 24	struct timespec64	ia_atime;
 25	struct timespec64	ia_mtime;
 26	struct timespec64	ia_ctime;
 27
 28	struct simple_xattrs	xattrs;
 29};
 30
 31/* +1 to avoid triggering overflow warning when negating it */
 32#define KN_DEACTIVATED_BIAS		(INT_MIN + 1)
 33
 34/* KERNFS_TYPE_MASK and types are defined in include/linux/kernfs.h */
 35
 36/**
 37 * kernfs_root - find out the kernfs_root a kernfs_node belongs to
 38 * @kn: kernfs_node of interest
 39 *
 40 * Return the kernfs_root @kn belongs to.
 41 */
 42static inline struct kernfs_root *kernfs_root(struct kernfs_node *kn)
 43{
 44	/* if parent exists, it's always a dir; otherwise, @sd is a dir */
 45	if (kn->parent)
 46		kn = kn->parent;
 47	return kn->dir.root;
 48}
 49
 50/*
 51 * mount.c
 52 */
 53struct kernfs_super_info {
 54	struct super_block	*sb;
 55
 56	/*
 57	 * The root associated with this super_block.  Each super_block is
 58	 * identified by the root and ns it's associated with.
 59	 */
 60	struct kernfs_root	*root;
 61
 62	/*
 63	 * Each sb is associated with one namespace tag, currently the
 64	 * network namespace of the task which mounted this kernfs
 65	 * instance.  If multiple tags become necessary, make the following
 66	 * an array and compare kernfs_node tag against every entry.
 67	 */
 68	const void		*ns;
 69
 70	/* anchored at kernfs_root->supers, protected by kernfs_mutex */
 71	struct list_head	node;
 72};
 73#define kernfs_info(SB) ((struct kernfs_super_info *)(SB->s_fs_info))
 74
 75static inline struct kernfs_node *kernfs_dentry_node(struct dentry *dentry)
 76{
 77	if (d_really_is_negative(dentry))
 78		return NULL;
 79	return d_inode(dentry)->i_private;
 80}
 81
 82extern const struct super_operations kernfs_sops;
 83extern struct kmem_cache *kernfs_node_cache, *kernfs_iattrs_cache;
 84
 85/*
 86 * inode.c
 87 */
 88extern const struct xattr_handler *kernfs_xattr_handlers[];
 89void kernfs_evict_inode(struct inode *inode);
 90int kernfs_iop_permission(struct inode *inode, int mask);
 91int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr);
 92int kernfs_iop_getattr(const struct path *path, struct kstat *stat,
 93		       u32 request_mask, unsigned int query_flags);
 94ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size);
 95int __kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr);
 96
 97/*
 98 * dir.c
 99 */
100extern struct mutex kernfs_mutex;
101extern const struct dentry_operations kernfs_dops;
102extern const struct file_operations kernfs_dir_fops;
103extern const struct inode_operations kernfs_dir_iops;
104
105struct kernfs_node *kernfs_get_active(struct kernfs_node *kn);
106void kernfs_put_active(struct kernfs_node *kn);
107int kernfs_add_one(struct kernfs_node *kn);
108struct kernfs_node *kernfs_new_node(struct kernfs_node *parent,
109				    const char *name, umode_t mode,
110				    kuid_t uid, kgid_t gid,
111				    unsigned flags);
112struct kernfs_node *kernfs_find_and_get_node_by_ino(struct kernfs_root *root,
113						    unsigned int ino);
114
115/*
116 * file.c
117 */
118extern const struct file_operations kernfs_file_fops;
119
120void kernfs_drain_open_files(struct kernfs_node *kn);
121
122/*
123 * symlink.c
124 */
125extern const struct inode_operations kernfs_symlink_iops;
126
127#endif	/* __KERNFS_INTERNAL_H */