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
  21 struct 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  */
  44 static 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  */
  55 struct 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
  77 static 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
  84 extern const struct super_operations kernfs_sops;
  85 extern struct kmem_cache *kernfs_node_cache, *kernfs_iattrs_cache;
  86
  87 /*
  88  * inode.c
  89  */
  90 extern const struct xattr_handler *kernfs_xattr_handlers[];
  91 void kernfs_evict_inode(struct inode *inode);
  92 int kernfs_iop_permission(struct inode *inode, int mask);
  93 int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr);
  94 int kernfs_iop_getattr(const struct path *path, struct kstat *stat,
  95                        u32 request_mask, unsigned int query_flags);
  96 ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size);
  97 int __kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr);
  98
  99 /*
 100  * dir.c
 101  */
 102 extern struct mutex kernfs_mutex;
 103 extern const struct dentry_operations kernfs_dops;
 104 extern const struct file_operations kernfs_dir_fops;
 105 extern const struct inode_operations kernfs_dir_iops;
 106
 107 struct kernfs_node *kernfs_get_active(struct kernfs_node *kn);
 108 void kernfs_put_active(struct kernfs_node *kn);
 109 int kernfs_add_one(struct kernfs_node *kn);
 110 struct 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  */
 118 extern const struct file_operations kernfs_file_fops;
 119
 120 void kernfs_drain_open_files(struct kernfs_node *kn);
 121
 122 /*
 123  * symlink.c
 124  */
 125 extern const struct inode_operations kernfs_symlink_iops;
 126
 127 #endif  /* __KERNFS_INTERNAL_H */