include/linux/proc_fs.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * The proc filesystem constants/structures
   4  */
   5 #ifndef _LINUX_PROC_FS_H
   6 #define _LINUX_PROC_FS_H
   7
   8 #include <linux/compiler.h>
   9 #include <linux/types.h>
  10 #include <linux/fs.h>
  11
  12 struct proc_dir_entry;
  13 struct seq_file;
  14 struct seq_operations;
  15
  16 enum {
  17         /*
  18          * All /proc entries using this ->proc_ops instance are never removed.
  19          *
  20          * If in doubt, ignore this flag.
  21          */
  22 #ifdef MODULE
  23         PROC_ENTRY_PERMANENT = 0U,
  24 #else
  25         PROC_ENTRY_PERMANENT = 1U << 0,
  26 #endif
  27 };
  28
  29 struct proc_ops {
  30         unsigned int proc_flags;
  31         int     (*proc_open)(struct inode *, struct file *);
  32         ssize_t (*proc_read)(struct file *, char __user *, size_t, loff_t *);
  33         ssize_t (*proc_read_iter)(struct kiocb *, struct iov_iter *);
  34         ssize_t (*proc_write)(struct file *, const char __user *, size_t, loff_t *);
  35         /* mandatory unless nonseekable_open() or equivalent is used */
  36         loff_t  (*proc_lseek)(struct file *, loff_t, int);
  37         int     (*proc_release)(struct inode *, struct file *);
  38         __poll_t (*proc_poll)(struct file *, struct poll_table_struct *);
  39         long    (*proc_ioctl)(struct file *, unsigned int, unsigned long);
  40 #ifdef CONFIG_COMPAT
  41         long    (*proc_compat_ioctl)(struct file *, unsigned int, unsigned long);
  42 #endif
  43         int     (*proc_mmap)(struct file *, struct vm_area_struct *);
  44         unsigned long (*proc_get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
  45 } __randomize_layout;
  46
  47 /* definitions for hide_pid field */
  48 enum proc_hidepid {
  49         HIDEPID_OFF       = 0,
  50         HIDEPID_NO_ACCESS = 1,
  51         HIDEPID_INVISIBLE = 2,
  52         HIDEPID_NOT_PTRACEABLE = 4, /* Limit pids to only ptraceable pids */
  53 };
  54
  55 /* definitions for proc mount option pidonly */
  56 enum proc_pidonly {
  57         PROC_PIDONLY_OFF = 0,
  58         PROC_PIDONLY_ON  = 1,
  59 };
  60
  61 struct proc_fs_info {
  62         struct pid_namespace *pid_ns;
  63         struct dentry *proc_self;        /* For /proc/self */
  64         struct dentry *proc_thread_self; /* For /proc/thread-self */
  65         kgid_t pid_gid;
  66         enum proc_hidepid hide_pid;
  67         enum proc_pidonly pidonly;
  68         struct rcu_head rcu;
  69 };
  70
  71 static inline struct proc_fs_info *proc_sb_info(struct super_block *sb)
  72 {
  73         return sb->s_fs_info;
  74 }
  75
  76 #ifdef CONFIG_PROC_FS
  77
  78 typedef int (*proc_write_t)(struct file *, char *, size_t);
  79
  80 extern void proc_root_init(void);
  81 extern void proc_flush_pid(struct pid *);
  82
  83 extern struct proc_dir_entry *proc_symlink(const char *,
  84                 struct proc_dir_entry *, const char *);
  85 struct proc_dir_entry *_proc_mkdir(const char *, umode_t, struct proc_dir_entry *, void *, bool);
  86 extern struct proc_dir_entry *proc_mkdir(const char *, struct proc_dir_entry *);
  87 extern struct proc_dir_entry *proc_mkdir_data(const char *, umode_t,
  88                                               struct proc_dir_entry *, void *);
  89 extern struct proc_dir_entry *proc_mkdir_mode(const char *, umode_t,
  90                                               struct proc_dir_entry *);
  91 struct proc_dir_entry *proc_create_mount_point(const char *name);
  92
  93 struct proc_dir_entry *proc_create_seq_private(const char *name, umode_t mode,
  94                 struct proc_dir_entry *parent, const struct seq_operations *ops,
  95                 unsigned int state_size, void *data);
  96 #define proc_create_seq_data(name, mode, parent, ops, data) \
  97         proc_create_seq_private(name, mode, parent, ops, 0, data)
  98 #define proc_create_seq(name, mode, parent, ops) \
  99         proc_create_seq_private(name, mode, parent, ops, 0, NULL)
 100 struct proc_dir_entry *proc_create_single_data(const char *name, umode_t mode,
 101                 struct proc_dir_entry *parent,
 102                 int (*show)(struct seq_file *, void *), void *data);
 103 #define proc_create_single(name, mode, parent, show) \
 104         proc_create_single_data(name, mode, parent, show, NULL)
 105
 106 extern struct proc_dir_entry *proc_create_data(const char *, umode_t,
 107                                                struct proc_dir_entry *,
 108                                                const struct proc_ops *,
 109                                                void *);
 110
 111 struct proc_dir_entry *proc_create(const char *name, umode_t mode, struct proc_dir_entry *parent, const struct proc_ops *proc_ops);
 112 extern void proc_set_size(struct proc_dir_entry *, loff_t);
 113 extern void proc_set_user(struct proc_dir_entry *, kuid_t, kgid_t);
 114
 115 /*
 116  * Obtain the private data passed by user through proc_create_data() or
 117  * related.
 118  */
 119 static inline void *pde_data(const struct inode *inode)
 120 {
 121         return inode->i_private;
 122 }
 123
 124 extern void *proc_get_parent_data(const struct inode *);
 125 extern void proc_remove(struct proc_dir_entry *);
 126 extern void remove_proc_entry(const char *, struct proc_dir_entry *);
 127 extern int remove_proc_subtree(const char *, struct proc_dir_entry *);
 128
 129 struct proc_dir_entry *proc_create_net_data(const char *name, umode_t mode,
 130                 struct proc_dir_entry *parent, const struct seq_operations *ops,
 131                 unsigned int state_size, void *data);
 132 #define proc_create_net(name, mode, parent, ops, state_size) \
 133         proc_create_net_data(name, mode, parent, ops, state_size, NULL)
 134 struct proc_dir_entry *proc_create_net_single(const char *name, umode_t mode,
 135                 struct proc_dir_entry *parent,
 136                 int (*show)(struct seq_file *, void *), void *data);
 137 struct proc_dir_entry *proc_create_net_data_write(const char *name, umode_t mode,
 138                                                   struct proc_dir_entry *parent,
 139                                                   const struct seq_operations *ops,
 140                                                   proc_write_t write,
 141                                                   unsigned int state_size, void *data);
 142 struct proc_dir_entry *proc_create_net_single_write(const char *name, umode_t mode,
 143                                                     struct proc_dir_entry *parent,
 144                                                     int (*show)(struct seq_file *, void *),
 145                                                     proc_write_t write,
 146                                                     void *data);
 147 extern struct pid *tgid_pidfd_to_pid(const struct file *file);
 148
 149 struct bpf_iter_aux_info;
 150 extern int bpf_iter_init_seq_net(void *priv_data, struct bpf_iter_aux_info *aux);
 151 extern void bpf_iter_fini_seq_net(void *priv_data);
 152
 153 #ifdef CONFIG_PROC_PID_ARCH_STATUS
 154 /*
 155  * The architecture which selects CONFIG_PROC_PID_ARCH_STATUS must
 156  * provide proc_pid_arch_status() definition.
 157  */
 158 int proc_pid_arch_status(struct seq_file *m, struct pid_namespace *ns,
 159                         struct pid *pid, struct task_struct *task);
 160 #endif /* CONFIG_PROC_PID_ARCH_STATUS */
 161
 162 void arch_report_meminfo(struct seq_file *m);
 163 void arch_proc_pid_thread_features(struct seq_file *m, struct task_struct *task);
 164
 165 #else /* CONFIG_PROC_FS */
 166
 167 static inline void proc_root_init(void)
 168 {
 169 }
 170
 171 static inline void proc_flush_pid(struct pid *pid)
 172 {
 173 }
 174
 175 static inline struct proc_dir_entry *proc_symlink(const char *name,
 176                 struct proc_dir_entry *parent,const char *dest) { return NULL;}
 177 static inline struct proc_dir_entry *proc_mkdir(const char *name,
 178         struct proc_dir_entry *parent) {return NULL;}
 179 static inline struct proc_dir_entry *proc_create_mount_point(const char *name) { return NULL; }
 180 static inline struct proc_dir_entry *_proc_mkdir(const char *name, umode_t mode,
 181                 struct proc_dir_entry *parent, void *data, bool force_lookup)
 182 {
 183         return NULL;
 184 }
 185 static inline struct proc_dir_entry *proc_mkdir_data(const char *name,
 186         umode_t mode, struct proc_dir_entry *parent, void *data) { return NULL; }
 187 static inline struct proc_dir_entry *proc_mkdir_mode(const char *name,
 188         umode_t mode, struct proc_dir_entry *parent) { return NULL; }
 189 #define proc_create_seq_private(name, mode, parent, ops, size, data) ({NULL;})
 190 #define proc_create_seq_data(name, mode, parent, ops, data) ({NULL;})
 191 #define proc_create_seq(name, mode, parent, ops) ({NULL;})
 192 #define proc_create_single(name, mode, parent, show) ({NULL;})
 193 #define proc_create_single_data(name, mode, parent, show, data) ({NULL;})
 194
 195 static inline struct proc_dir_entry *
 196 proc_create(const char *name, umode_t mode, struct proc_dir_entry *parent,
 197             const struct proc_ops *proc_ops)
 198 { return NULL; }
 199
 200 static inline struct proc_dir_entry *
 201 proc_create_data(const char *name, umode_t mode, struct proc_dir_entry *parent,
 202                  const struct proc_ops *proc_ops, void *data)
 203 { return NULL; }
 204
 205 static inline void proc_set_size(struct proc_dir_entry *de, loff_t size) {}
 206 static inline void proc_set_user(struct proc_dir_entry *de, kuid_t uid, kgid_t gid) {}
 207 static inline void *pde_data(const struct inode *inode) {BUG(); return NULL;}
 208 static inline void *proc_get_parent_data(const struct inode *inode) { BUG(); return NULL; }
 209
 210 static inline void proc_remove(struct proc_dir_entry *de) {}
 211 #define remove_proc_entry(name, parent) do {} while (0)
 212 static inline int remove_proc_subtree(const char *name, struct proc_dir_entry *parent) { return 0; }
 213
 214 #define proc_create_net_data(name, mode, parent, ops, state_size, data) ({NULL;})
 215 #define proc_create_net_data_write(name, mode, parent, ops, write, state_size, data) ({NULL;})
 216 #define proc_create_net(name, mode, parent, state_size, ops) ({NULL;})
 217 #define proc_create_net_single(name, mode, parent, show, data) ({NULL;})
 218 #define proc_create_net_single_write(name, mode, parent, show, write, data) ({NULL;})
 219
 220 static inline struct pid *tgid_pidfd_to_pid(const struct file *file)
 221 {
 222         return ERR_PTR(-EBADF);
 223 }
 224
 225 #endif /* CONFIG_PROC_FS */
 226
 227 struct net;
 228
 229 static inline struct proc_dir_entry *proc_net_mkdir(
 230         struct net *net, const char *name, struct proc_dir_entry *parent)
 231 {
 232         return _proc_mkdir(name, 0, parent, net, true);
 233 }
 234
 235 struct ns_common;
 236 int open_related_ns(struct ns_common *ns,
 237                    struct ns_common *(*get_ns)(struct ns_common *ns));
 238
 239 /* get the associated pid namespace for a file in procfs */
 240 static inline struct pid_namespace *proc_pid_ns(struct super_block *sb)
 241 {
 242         return proc_sb_info(sb)->pid_ns;
 243 }
 244
 245 bool proc_ns_file(const struct file *file);
 246
 247 #endif /* _LINUX_PROC_FS_H */