LXR linux/fs/kernfs/kernfs-internal.h

   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        atomic_t                nr_user_xattrs;
  30        atomic_t                user_xattr_size;
  31};
  32
  33/* +1 to avoid triggering overflow warning when negating it */
  34#define KN_DEACTIVATED_BIAS             (INT_MIN + 1)
  35
  36/* KERNFS_TYPE_MASK and types are defined in include/linux/kernfs.h */
  37
  38/**
  39 * kernfs_root - find out the kernfs_root a kernfs_node belongs to
  40 * @kn: kernfs_node of interest
  41 *
  42 * Return the kernfs_root @kn belongs to.
  43 */
  44static inline struct kernfs_root *kernfs_root(struct kernfs_node *kn)
  45{
  46        /* if parent exists, it's always a dir; otherwise, @sd is a dir */
  47        if (kn->parent)
  48                kn = kn->parent;
  49        return kn->dir.root;
  50}
  51
  52/*
  53 * mount.c
  54 */
  55struct kernfs_super_info {
  56        struct super_block      *sb;
  57
  58        /*
  59         * The root associated with this super_block.  Each super_block is
  60         * identified by the root and ns it's associated with.
  61         */
  62        struct kernfs_root      *root;
  63
  64        /*
  65         * Each sb is associated with one namespace tag, currently the
  66         * network namespace of the task which mounted this kernfs
  67         * instance.  If multiple tags become necessary, make the following
  68         * an array and compare kernfs_node tag against every entry.
  69         */
  70        const void              *ns;
  71
  72        /* anchored at kernfs_root->supers, protected by kernfs_mutex */
  73        struct list_head        node;
  74};
  75#define kernfs_info(SB) ((struct kernfs_super_info *)(SB->s_fs_info))
  76
  77static inline struct kernfs_node *kernfs_dentry_node(struct dentry *dentry)
  78{
  79        if (d_really_is_negative(dentry))
  80                return NULL;
  81        return d_inode(dentry)->i_private;
  82}
  83
  84extern const struct super_operations kernfs_sops;
  85extern struct kmem_cache *kernfs_node_cache, *kernfs_iattrs_cache;
  86
  87/*
  88 * inode.c
  89 */
  90extern const struct xattr_handler *kernfs_xattr_handlers[];
  91void kernfs_evict_inode(struct inode *inode);
  92int kernfs_iop_permission(struct inode *inode, int mask);
  93int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr);
  94int kernfs_iop_getattr(const struct path *path, struct kstat *stat,
  95                       u32 request_mask, unsigned int query_flags);
  96ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size);
  97int __kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr);
  98
  99/*
 100 * dir.c
 101 */
 102extern struct mutex kernfs_mutex;
 103extern const struct dentry_operations kernfs_dops;
 104extern const struct file_operations kernfs_dir_fops;
 105extern const struct inode_operations kernfs_dir_iops;
 106
 107struct kernfs_node *kernfs_get_active(struct kernfs_node *kn);
 108void kernfs_put_active(struct kernfs_node *kn);
 109int kernfs_add_one(struct kernfs_node *kn);
 110struct kernfs_node *kernfs_new_node(struct kernfs_node *parent,
 111                                    const char *name, umode_t mode,
 112                                    kuid_t uid, kgid_t gid,
 113                                    unsigned flags);
 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 */
 128