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
  18 struct ctl_table_header;
  19 struct mempolicy;
  20
  21 /*
  22  * This is not completely implemented yet. The idea is to
  23  * create an in-memory tree (like the actual /proc filesystem
  24  * tree) of these proc_dir_entries, so that we can dynamically
  25  * add new files to /proc.
  26  *
  27  * The "next" pointer creates a linked list of one /proc directory,
  28  * while parent/subdir create the directory structure (every
  29  * /proc file has a parent, but "subdir" is NULL for all
  30  * non-directory entries).
  31  */
  32 struct proc_dir_entry {
  33         unsigned int low_ino;
  34         umode_t mode;
  35         nlink_t nlink;
  36         kuid_t uid;
  37         kgid_t gid;
  38         loff_t size;
  39         const struct inode_operations *proc_iops;
  40         const struct file_operations *proc_fops;
  41         struct proc_dir_entry *next, *parent, *subdir;
  42         void *data;
  43         atomic_t count;         /* use count */
  44         atomic_t in_use;        /* number of callers into module in progress; */
  45                         /* negative -> it's going away RSN */
  46         struct completion *pde_unload_completion;
  47         struct list_head pde_openers;   /* who did ->open, but not ->release */
  48         spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
  49         u8 namelen;
  50         char name[];
  51 };
  52
  53 union proc_op {
  54         int (*proc_get_link)(struct dentry *, struct path *);
  55         int (*proc_show)(struct seq_file *m,
  56                 struct pid_namespace *ns, struct pid *pid,
  57                 struct task_struct *task);
  58 };
  59
  60 struct proc_inode {
  61         struct pid *pid;
  62         int fd;
  63         union proc_op op;
  64         struct proc_dir_entry *pde;
  65         struct ctl_table_header *sysctl;
  66         struct ctl_table *sysctl_entry;
  67         struct proc_ns ns;
  68         struct inode vfs_inode;
  69 };
  70
  71 /*
  72  * General functions
  73  */
  74 static inline struct proc_inode *PROC_I(const struct inode *inode)
  75 {
  76         return container_of(inode, struct proc_inode, vfs_inode);
  77 }
  78
  79 static inline struct proc_dir_entry *PDE(const struct inode *inode)
  80 {
  81         return PROC_I(inode)->pde;
  82 }
  83
  84 static inline void *__PDE_DATA(const struct inode *inode)
  85 {
  86         return PDE(inode)->data;
  87 }
  88
  89 static inline struct pid *proc_pid(struct inode *inode)
  90 {
  91         return PROC_I(inode)->pid;
  92 }
  93
  94 static inline struct task_struct *get_proc_task(struct inode *inode)
  95 {
  96         return get_pid_task(proc_pid(inode), PIDTYPE_PID);
  97 }
  98
  99 static inline int task_dumpable(struct task_struct *task)
 100 {
 101         int dumpable = 0;
 102         struct mm_struct *mm;
 103
 104         task_lock(task);
 105         mm = task->mm;
 106         if (mm)
 107                 dumpable = get_dumpable(mm);
 108         task_unlock(task);
 109         if (dumpable == SUID_DUMP_USER)
 110                 return 1;
 111         return 0;
 112 }
 113
 114 static inline unsigned name_to_int(const struct qstr *qstr)
 115 {
 116         const char *name = qstr->name;
 117         int len = qstr->len;
 118         unsigned n = 0;
 119
 120         if (len > 1 && *name == '0')
 121                 goto out;
 122         while (len-- > 0) {
 123                 unsigned c = *name++ - '0';
 124                 if (c > 9)
 125                         goto out;
 126                 if (n >= (~0U-9)/10)
 127                         goto out;
 128                 n *= 10;
 129                 n += c;
 130         }
 131         return n;
 132 out:
 133         return ~0U;
 134 }
 135
 136 /*
 137  * Offset of the first process in the /proc root directory..
 138  */
 139 #define FIRST_PROCESS_ENTRY 256
 140
 141 /* Worst case buffer size needed for holding an integer. */
 142 #define PROC_NUMBUF 13
 143
 144 /*
 145  * array.c
 146  */
 147 extern const struct file_operations proc_tid_children_operations;
 148
 149 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
 150                          struct pid *, struct task_struct *);
 151 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
 152                           struct pid *, struct task_struct *);
 153 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
 154                            struct pid *, struct task_struct *);
 155 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
 156                           struct pid *, struct task_struct *);
 157
 158 /*
 159  * base.c
 160  */
 161 extern const struct dentry_operations pid_dentry_operations;
 162 extern int pid_getattr(struct vfsmount *, struct dentry *, struct kstat *);
 163 extern int proc_setattr(struct dentry *, struct iattr *);
 164 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *);
 165 extern int pid_revalidate(struct dentry *, unsigned int);
 166 extern int pid_delete_dentry(const struct dentry *);
 167 extern int proc_pid_readdir(struct file *, struct dir_context *);
 168 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
 169 extern loff_t mem_lseek(struct file *, loff_t, int);
 170
 171 /* Lookups */
 172 typedef int instantiate_t(struct inode *, struct dentry *,
 173                                      struct task_struct *, const void *);
 174 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
 175                            instantiate_t, struct task_struct *, const void *);
 176
 177 /*
 178  * generic.c
 179  */
 180 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
 181 extern struct dentry *proc_lookup_de(struct proc_dir_entry *, struct inode *,
 182                                      struct dentry *);
 183 extern int proc_readdir(struct file *, struct dir_context *);
 184 extern int proc_readdir_de(struct proc_dir_entry *, struct file *, struct dir_context *);
 185
 186 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
 187 {
 188         atomic_inc(&pde->count);
 189         return pde;
 190 }
 191 extern void pde_put(struct proc_dir_entry *);
 192
 193 /*
 194  * inode.c
 195  */
 196 struct pde_opener {
 197         struct file *file;
 198         struct list_head lh;
 199         int closing;
 200         struct completion *c;
 201 };
 202
 203 extern const struct inode_operations proc_pid_link_inode_operations;
 204
 205 extern void proc_init_inodecache(void);
 206 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
 207 extern int proc_fill_super(struct super_block *);
 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 sysctl_head_put(struct ctl_table_header *);
 245 #else
 246 static inline void proc_sys_init(void) { }
 247 static inline void sysctl_head_put(struct ctl_table_header *head) { }
 248 #endif
 249
 250 /*
 251  * proc_tty.c
 252  */
 253 #ifdef CONFIG_TTY
 254 extern void proc_tty_init(void);
 255 #else
 256 static inline void proc_tty_init(void) {}
 257 #endif
 258
 259 /*
 260  * root.c
 261  */
 262 extern struct proc_dir_entry proc_root;
 263
 264 extern void proc_self_init(void);
 265 extern int proc_remount(struct super_block *, int *, char *);
 266
 267 /*
 268  * task_[no]mmu.c
 269  */
 270 struct proc_maps_private {
 271         struct pid *pid;
 272         struct task_struct *task;
 273 #ifdef CONFIG_MMU
 274         struct vm_area_struct *tail_vma;
 275 #endif
 276 #ifdef CONFIG_NUMA
 277         struct mempolicy *task_mempolicy;
 278 #endif
 279 };
 280
 281 extern const struct file_operations proc_pid_maps_operations;
 282 extern const struct file_operations proc_tid_maps_operations;
 283 extern const struct file_operations proc_pid_numa_maps_operations;
 284 extern const struct file_operations proc_tid_numa_maps_operations;
 285 extern const struct file_operations proc_pid_smaps_operations;
 286 extern const struct file_operations proc_tid_smaps_operations;
 287 extern const struct file_operations proc_clear_refs_operations;
 288 extern const struct file_operations proc_pagemap_operations;
 289
 290 extern unsigned long task_vsize(struct mm_struct *);
 291 extern unsigned long task_statm(struct mm_struct *,
 292                                 unsigned long *, unsigned long *,
 293                                 unsigned long *, unsigned long *);
 294 extern void task_mem(struct seq_file *, struct mm_struct *);