fs/proc/internal.h

   1 /* Internal procfs definitions
   2  *
   3  * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/proc_fs.h>
  13 #include <linux/proc_ns.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/atomic.h>
  16 #include <linux/binfmts.h>
  17 #include <linux/sched/coredump.h>
  18 #include <linux/sched/task.h>
  19
  20 struct ctl_table_header;
  21 struct mempolicy;
  22
  23 /*
  24  * This is not completely implemented yet. The idea is to
  25  * create an in-memory tree (like the actual /proc filesystem
  26  * tree) of these proc_dir_entries, so that we can dynamically
  27  * add new files to /proc.
  28  *
  29  * parent/subdir are used for the directory structure (every /proc file has a
  30  * parent, but "subdir" is empty for all non-directory entries).
  31  * subdir_node is used to build the rb tree "subdir" of the parent.
  32  */
  33 struct proc_dir_entry {
  34         unsigned int low_ino;
  35         umode_t mode;
  36         nlink_t nlink;
  37         kuid_t uid;
  38         kgid_t gid;
  39         loff_t size;
  40         const struct inode_operations *proc_iops;
  41         const struct file_operations *proc_fops;
  42         struct proc_dir_entry *parent;
  43         struct rb_root_cached subdir;
  44         struct rb_node subdir_node;
  45         void *data;
  46         atomic_t count;         /* use count */
  47         atomic_t in_use;        /* number of callers into module in progress; */
  48                         /* negative -> it's going away RSN */
  49         struct completion *pde_unload_completion;
  50         struct list_head pde_openers;   /* who did ->open, but not ->release */
  51         spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
  52         u8 namelen;
  53         char name[];
  54 } __randomize_layout;
  55
  56 union proc_op {
  57         int (*proc_get_link)(struct dentry *, struct path *);
  58         int (*proc_show)(struct seq_file *m,
  59                 struct pid_namespace *ns, struct pid *pid,
  60                 struct task_struct *task);
  61 };
  62
  63 struct proc_inode {
  64         struct pid *pid;
  65         unsigned int fd;
  66         union proc_op op;
  67         struct proc_dir_entry *pde;
  68         struct ctl_table_header *sysctl;
  69         struct ctl_table *sysctl_entry;
  70         struct hlist_node sysctl_inodes;
  71         const struct proc_ns_operations *ns_ops;
  72         struct inode vfs_inode;
  73 } __randomize_layout;
  74
  75 /*
  76  * General functions
  77  */
  78 static inline struct proc_inode *PROC_I(const struct inode *inode)
  79 {
  80         return container_of(inode, struct proc_inode, vfs_inode);
  81 }
  82
  83 static inline struct proc_dir_entry *PDE(const struct inode *inode)
  84 {
  85         return PROC_I(inode)->pde;
  86 }
  87
  88 static inline void *__PDE_DATA(const struct inode *inode)
  89 {
  90         return PDE(inode)->data;
  91 }
  92
  93 static inline struct pid *proc_pid(struct inode *inode)
  94 {
  95         return PROC_I(inode)->pid;
  96 }
  97
  98 static inline struct task_struct *get_proc_task(struct inode *inode)
  99 {
 100         return get_pid_task(proc_pid(inode), PIDTYPE_PID);
 101 }
 102
 103 void task_dump_owner(struct task_struct *task, mode_t mode,
 104                      kuid_t *ruid, kgid_t *rgid);
 105
 106 static inline unsigned name_to_int(const struct qstr *qstr)
 107 {
 108         const char *name = qstr->name;
 109         int len = qstr->len;
 110         unsigned n = 0;
 111
 112         if (len > 1 && *name == '0')
 113                 goto out;
 114         while (len-- > 0) {
 115                 unsigned c = *name++ - '0';
 116                 if (c > 9)
 117                         goto out;
 118                 if (n >= (~0U-9)/10)
 119                         goto out;
 120                 n *= 10;
 121                 n += c;
 122         }
 123         return n;
 124 out:
 125         return ~0U;
 126 }
 127
 128 /*
 129  * Offset of the first process in the /proc root directory..
 130  */
 131 #define FIRST_PROCESS_ENTRY 256
 132
 133 /* Worst case buffer size needed for holding an integer. */
 134 #define PROC_NUMBUF 13
 135
 136 /*
 137  * array.c
 138  */
 139 extern const struct file_operations proc_tid_children_operations;
 140
 141 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
 142                          struct pid *, struct task_struct *);
 143 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
 144                           struct pid *, struct task_struct *);
 145 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
 146                            struct pid *, struct task_struct *);
 147 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
 148                           struct pid *, struct task_struct *);
 149
 150 /*
 151  * base.c
 152  */
 153 extern const struct dentry_operations pid_dentry_operations;
 154 extern int pid_getattr(const struct path *, struct kstat *, u32, unsigned int);
 155 extern int proc_setattr(struct dentry *, struct iattr *);
 156 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
 157 extern int pid_revalidate(struct dentry *, unsigned int);
 158 extern int pid_delete_dentry(const struct dentry *);
 159 extern int proc_pid_readdir(struct file *, struct dir_context *);
 160 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
 161 extern loff_t mem_lseek(struct file *, loff_t, int);
 162
 163 /* Lookups */
 164 typedef int instantiate_t(struct inode *, struct dentry *,
 165                                      struct task_struct *, const void *);
 166 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
 167                            instantiate_t, struct task_struct *, const void *);
 168
 169 /*
 170  * generic.c
 171  */
 172 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
 173 extern struct dentry *proc_lookup_de(struct proc_dir_entry *, struct inode *,
 174                                      struct dentry *);
 175 extern int proc_readdir(struct file *, struct dir_context *);
 176 extern int proc_readdir_de(struct proc_dir_entry *, struct file *, struct dir_context *);
 177
 178 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
 179 {
 180         atomic_inc(&pde->count);
 181         return pde;
 182 }
 183 extern void pde_put(struct proc_dir_entry *);
 184
 185 static inline bool is_empty_pde(const struct proc_dir_entry *pde)
 186 {
 187         return S_ISDIR(pde->mode) && !pde->proc_iops;
 188 }
 189
 190 /*
 191  * inode.c
 192  */
 193 struct pde_opener {
 194         struct file *file;
 195         struct list_head lh;
 196         bool closing;
 197         struct completion *c;
 198 };
 199 extern const struct inode_operations proc_link_inode_operations;
 200
 201 extern const struct inode_operations proc_pid_link_inode_operations;
 202
 203 extern void proc_init_inodecache(void);
 204 void set_proc_pid_nlink(void);
 205 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
 206 extern int proc_fill_super(struct super_block *, void *data, int flags);
 207 extern void proc_entry_rundown(struct proc_dir_entry *);
 208
 209 /*
 210  * proc_namespaces.c
 211  */
 212 extern const struct inode_operations proc_ns_dir_inode_operations;
 213 extern const struct file_operations proc_ns_dir_operations;
 214
 215 /*
 216  * proc_net.c
 217  */
 218 extern const struct file_operations proc_net_operations;
 219 extern const struct inode_operations proc_net_inode_operations;
 220
 221 #ifdef CONFIG_NET
 222 extern int proc_net_init(void);
 223 #else
 224 static inline int proc_net_init(void) { return 0; }
 225 #endif
 226
 227 /*
 228  * proc_self.c
 229  */
 230 extern int proc_setup_self(struct super_block *);
 231
 232 /*
 233  * proc_thread_self.c
 234  */
 235 extern int proc_setup_thread_self(struct super_block *);
 236 extern void proc_thread_self_init(void);
 237
 238 /*
 239  * proc_sysctl.c
 240  */
 241 #ifdef CONFIG_PROC_SYSCTL
 242 extern int proc_sys_init(void);
 243 extern void proc_sys_evict_inode(struct inode *inode,
 244                                  struct ctl_table_header *head);
 245 #else
 246 static inline void proc_sys_init(void) { }
 247 static inline void proc_sys_evict_inode(struct  inode *inode,
 248                                         struct ctl_table_header *head) { }
 249 #endif
 250
 251 /*
 252  * proc_tty.c
 253  */
 254 #ifdef CONFIG_TTY
 255 extern void proc_tty_init(void);
 256 #else
 257 static inline void proc_tty_init(void) {}
 258 #endif
 259
 260 /*
 261  * root.c
 262  */
 263 extern struct proc_dir_entry proc_root;
 264 extern int proc_parse_options(char *options, struct pid_namespace *pid);
 265
 266 extern void proc_self_init(void);
 267 extern int proc_remount(struct super_block *, int *, char *);
 268
 269 /*
 270  * task_[no]mmu.c
 271  */
 272 struct mem_size_stats;
 273 struct proc_maps_private {
 274         struct inode *inode;
 275         struct task_struct *task;
 276         struct mm_struct *mm;
 277         struct mem_size_stats *rollup;
 278 #ifdef CONFIG_MMU
 279         struct vm_area_struct *tail_vma;
 280 #endif
 281 #ifdef CONFIG_NUMA
 282         struct mempolicy *task_mempolicy;
 283 #endif
 284 } __randomize_layout;
 285
 286 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
 287
 288 extern const struct file_operations proc_pid_maps_operations;
 289 extern const struct file_operations proc_tid_maps_operations;
 290 extern const struct file_operations proc_pid_numa_maps_operations;
 291 extern const struct file_operations proc_tid_numa_maps_operations;
 292 extern const struct file_operations proc_pid_smaps_operations;
 293 extern const struct file_operations proc_pid_smaps_rollup_operations;
 294 extern const struct file_operations proc_tid_smaps_operations;
 295 extern const struct file_operations proc_clear_refs_operations;
 296 extern const struct file_operations proc_pagemap_operations;
 297
 298 extern unsigned long task_vsize(struct mm_struct *);
 299 extern unsigned long task_statm(struct mm_struct *,
 300                                 unsigned long *, unsigned long *,
 301                                 unsigned long *, unsigned long *);
 302 extern void task_mem(struct seq_file *, struct mm_struct *);