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/rwsem.h> 17 #include <linux/xattr.h> 18 19 #include <linux/kernfs.h> 20 #include <linux/fs_context.h> 21 22 struct kernfs_iattrs { 23 kuid_t ia_uid; 24 kgid_t ia_gid; 25 struct timespec64 ia_atime; 26 struct timespec64 ia_mtime; 27 struct timespec64 ia_ctime; 28 29 struct simple_xattrs xattrs; 30 atomic_t nr_user_xattrs; 31 atomic_t user_xattr_size; 32 }; 33 34 /* +1 to avoid triggering overflow warning when negating it */ 35 #define KN_DEACTIVATED_BIAS (INT_MIN + 1) 36 37 /* KERNFS_TYPE_MASK and types are defined in include/linux/kernfs.h */ 38 39 /** 40 * kernfs_root - find out the kernfs_root a kernfs_node belongs to 41 * @kn: kernfs_node of interest 42 * 43 * Return the kernfs_root @kn belongs to. 44 */ 45 static inline struct kernfs_root *kernfs_root(struct kernfs_node *kn) 46 { 47 /* if parent exists, it's always a dir; otherwise, @sd is a dir */ 48 if (kn->parent) 49 kn = kn->parent; 50 return kn->dir.root; 51 } 52 53 /* 54 * mount.c 55 */ 56 struct kernfs_super_info { 57 struct super_block *sb; 58 59 /* 60 * The root associated with this super_block. Each super_block is 61 * identified by the root and ns it's associated with. 62 */ 63 struct kernfs_root *root; 64 65 /* 66 * Each sb is associated with one namespace tag, currently the 67 * network namespace of the task which mounted this kernfs 68 * instance. If multiple tags become necessary, make the following 69 * an array and compare kernfs_node tag against every entry. 70 */ 71 const void *ns; 72 73 /* anchored at kernfs_root->supers, protected by kernfs_rwsem */ 74 struct list_head node; 75 }; 76 #define kernfs_info(SB) ((struct kernfs_super_info *)(SB->s_fs_info)) 77 78 static inline struct kernfs_node *kernfs_dentry_node(struct dentry *dentry) 79 { 80 if (d_really_is_negative(dentry)) 81 return NULL; 82 return d_inode(dentry)->i_private; 83 } 84 85 static inline void kernfs_set_rev(struct kernfs_node *parent, 86 struct dentry *dentry) 87 { 88 dentry->d_time = parent->dir.rev; 89 } 90 91 static inline void kernfs_inc_rev(struct kernfs_node *parent) 92 { 93 parent->dir.rev++; 94 } 95 96 static inline bool kernfs_dir_changed(struct kernfs_node *parent, 97 struct dentry *dentry) 98 { 99 if (parent->dir.rev != dentry->d_time) 100 return true; 101 return false; 102 } 103 104 extern const struct super_operations kernfs_sops; 105 extern struct kmem_cache *kernfs_node_cache, *kernfs_iattrs_cache; 106 107 /* 108 * inode.c 109 */ 110 extern const struct xattr_handler *kernfs_xattr_handlers[]; 111 void kernfs_evict_inode(struct inode *inode); 112 int kernfs_iop_permission(struct user_namespace *mnt_userns, 113 struct inode *inode, int mask); 114 int kernfs_iop_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, 115 struct iattr *iattr); 116 int kernfs_iop_getattr(struct user_namespace *mnt_userns, 117 const struct path *path, struct kstat *stat, 118 u32 request_mask, unsigned int query_flags); 119 ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size); 120 int __kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr); 121 122 /* 123 * dir.c 124 */ 125 extern struct rw_semaphore kernfs_rwsem; 126 extern const struct dentry_operations kernfs_dops; 127 extern const struct file_operations kernfs_dir_fops; 128 extern const struct inode_operations kernfs_dir_iops; 129 130 struct kernfs_node *kernfs_get_active(struct kernfs_node *kn); 131 void kernfs_put_active(struct kernfs_node *kn); 132 int kernfs_add_one(struct kernfs_node *kn); 133 struct kernfs_node *kernfs_new_node(struct kernfs_node *parent, 134 const char *name, umode_t mode, 135 kuid_t uid, kgid_t gid, 136 unsigned flags); 137 138 /* 139 * file.c 140 */ 141 extern const struct file_operations kernfs_file_fops; 142 143 void kernfs_drain_open_files(struct kernfs_node *kn); 144 145 /* 146 * symlink.c 147 */ 148 extern const struct inode_operations kernfs_symlink_iops; 149 150 #endif /* __KERNFS_INTERNAL_H */ 151