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 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         const char *lsm;
  62 };
  63
  64 struct proc_inode {
  65         struct pid *pid;
  66         unsigned int fd;
  67         union proc_op op;
  68         struct proc_dir_entry *pde;
  69         struct ctl_table_header *sysctl;
  70         struct ctl_table *sysctl_entry;
  71         struct hlist_node sysctl_inodes;
  72         const struct proc_ns_operations *ns_ops;
  73         struct inode vfs_inode;
  74 } __randomize_layout;
  75
  76 /*
  77  * General functions
  78  */
  79 static inline struct proc_inode *PROC_I(const struct inode *inode)
  80 {
  81         return container_of(inode, struct proc_inode, vfs_inode);
  82 }
  83
  84 static inline struct proc_dir_entry *PDE(const struct inode *inode)
  85 {
  86         return PROC_I(inode)->pde;
  87 }
  88
  89 static inline void *__PDE_DATA(const struct inode *inode)
  90 {
  91         return PDE(inode)->data;
  92 }
  93
  94 static inline struct pid *proc_pid(struct inode *inode)
  95 {
  96         return PROC_I(inode)->pid;
  97 }
  98
  99 static inline struct task_struct *get_proc_task(struct inode *inode)
 100 {
 101         return get_pid_task(proc_pid(inode), PIDTYPE_PID);
 102 }
 103
 104 void task_dump_owner(struct task_struct *task, mode_t mode,
 105                      kuid_t *ruid, kgid_t *rgid);
 106
 107 static inline unsigned name_to_int(const struct qstr *qstr)
 108 {
 109         const char *name = qstr->name;
 110         int len = qstr->len;
 111         unsigned n = 0;
 112
 113         if (len > 1 && *name == '0')
 114                 goto out;
 115         while (len-- > 0) {
 116                 unsigned c = *name++ - '0';
 117                 if (c > 9)
 118                         goto out;
 119                 if (n >= (~0U-9)/10)
 120                         goto out;
 121                 n *= 10;
 122                 n += c;
 123         }
 124         return n;
 125 out:
 126         return ~0U;
 127 }
 128
 129 /*
 130  * Offset of the first process in the /proc root directory..
 131  */
 132 #define FIRST_PROCESS_ENTRY 256
 133
 134 /* Worst case buffer size needed for holding an integer. */
 135 #define PROC_NUMBUF 13
 136
 137 /*
 138  * array.c
 139  */
 140 extern const struct file_operations proc_tid_children_operations;
 141
 142 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
 143                          struct pid *, struct task_struct *);
 144 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
 145                           struct pid *, struct task_struct *);
 146 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
 147                            struct pid *, struct task_struct *);
 148 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
 149                           struct pid *, struct task_struct *);
 150
 151 /*
 152  * base.c
 153  */
 154 extern const struct dentry_operations pid_dentry_operations;
 155 extern int pid_getattr(const struct path *, struct kstat *, u32, unsigned int);
 156 extern int proc_setattr(struct dentry *, struct iattr *);
 157 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
 158 extern int pid_revalidate(struct dentry *, unsigned int);
 159 extern int pid_delete_dentry(const struct dentry *);
 160 extern int proc_pid_readdir(struct file *, struct dir_context *);
 161 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
 162 extern loff_t mem_lseek(struct file *, loff_t, int);
 163
 164 /* Lookups */
 165 typedef int instantiate_t(struct inode *, struct dentry *,
 166                                      struct task_struct *, const void *);
 167 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
 168                            instantiate_t, struct task_struct *, const void *);
 169
 170 /*
 171  * generic.c
 172  */
 173 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
 174 extern struct dentry *proc_lookup_de(struct proc_dir_entry *, struct inode *,
 175                                      struct dentry *);
 176 extern int proc_readdir(struct file *, struct dir_context *);
 177 extern int proc_readdir_de(struct proc_dir_entry *, struct file *, struct dir_context *);
 178
 179 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
 180 {
 181         atomic_inc(&pde->count);
 182         return pde;
 183 }
 184 extern void pde_put(struct proc_dir_entry *);
 185
 186 static inline bool is_empty_pde(const struct proc_dir_entry *pde)
 187 {
 188         return S_ISDIR(pde->mode) && !pde->proc_iops;
 189 }
 190
 191 /*
 192  * inode.c
 193  */
 194 struct pde_opener {
 195         struct file *file;
 196         struct list_head lh;
 197         bool closing;
 198         struct completion *c;
 199 };
 200 extern const struct inode_operations proc_link_inode_operations;
 201
 202 extern const struct inode_operations proc_pid_link_inode_operations;
 203
 204 extern void proc_init_inodecache(void);
 205 void set_proc_pid_nlink(void);
 206 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
 207 extern int proc_fill_super(struct super_block *, void *data, int flags);
 208 extern void proc_entry_rundown(struct proc_dir_entry *);
 209
 210 /*
 211  * proc_namespaces.c
 212  */
 213 extern const struct inode_operations proc_ns_dir_inode_operations;
 214 extern const struct file_operations proc_ns_dir_operations;
 215
 216 /*
 217  * proc_net.c
 218  */
 219 extern const struct file_operations proc_net_operations;
 220 extern const struct inode_operations proc_net_inode_operations;
 221
 222 #ifdef CONFIG_NET
 223 extern int proc_net_init(void);
 224 #else
 225 static inline int proc_net_init(void) { return 0; }
 226 #endif
 227
 228 /*
 229  * proc_self.c
 230  */
 231 extern int proc_setup_self(struct super_block *);
 232
 233 /*
 234  * proc_thread_self.c
 235  */
 236 extern int proc_setup_thread_self(struct super_block *);
 237 extern void proc_thread_self_init(void);
 238
 239 /*
 240  * proc_sysctl.c
 241  */
 242 #ifdef CONFIG_PROC_SYSCTL
 243 extern int proc_sys_init(void);
 244 extern void proc_sys_evict_inode(struct inode *inode,
 245                                  struct ctl_table_header *head);
 246 #else
 247 static inline void proc_sys_init(void) { }
 248 static inline void proc_sys_evict_inode(struct  inode *inode,
 249                                         struct ctl_table_header *head) { }
 250 #endif
 251
 252 /*
 253  * proc_tty.c
 254  */
 255 #ifdef CONFIG_TTY
 256 extern void proc_tty_init(void);
 257 #else
 258 static inline void proc_tty_init(void) {}
 259 #endif
 260
 261 /*
 262  * root.c
 263  */
 264 extern struct proc_dir_entry proc_root;
 265 extern int proc_parse_options(char *options, struct pid_namespace *pid);
 266
 267 extern void proc_self_init(void);
 268 extern int proc_remount(struct super_block *, int *, char *);
 269
 270 /*
 271  * task_[no]mmu.c
 272  */
 273 struct proc_maps_private {
 274         struct inode *inode;
 275         struct task_struct *task;
 276         struct mm_struct *mm;
 277 #ifdef CONFIG_MMU
 278         struct vm_area_struct *tail_vma;
 279 #endif
 280 #ifdef CONFIG_NUMA
 281         struct mempolicy *task_mempolicy;
 282 #endif
 283 } __randomize_layout;
 284
 285 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
 286
 287 extern const struct file_operations proc_pid_maps_operations;
 288 extern const struct file_operations proc_tid_maps_operations;
 289 extern const struct file_operations proc_pid_numa_maps_operations;
 290 extern const struct file_operations proc_tid_numa_maps_operations;
 291 extern const struct file_operations proc_pid_smaps_operations;
 292 extern const struct file_operations proc_tid_smaps_operations;
 293 extern const struct file_operations proc_clear_refs_operations;
 294 extern const struct file_operations proc_pagemap_operations;
 295
 296 extern unsigned long task_vsize(struct mm_struct *);
 297 extern unsigned long task_statm(struct mm_struct *,
 298                                 unsigned long *, unsigned long *,
 299                                 unsigned long *, unsigned long *);
 300 extern void task_mem(struct seq_file *, struct mm_struct *);