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_read)(struct task_struct *task, char *page);
  56         int (*proc_show)(struct seq_file *m,
  57                 struct pid_namespace *ns, struct pid *pid,
  58                 struct task_struct *task);
  59 };
  60
  61 struct proc_inode {
  62         struct pid *pid;
  63         int fd;
  64         union proc_op op;
  65         struct proc_dir_entry *pde;
  66         struct ctl_table_header *sysctl;
  67         struct ctl_table *sysctl_entry;
  68         struct proc_ns ns;
  69         struct inode vfs_inode;
  70 };
  71
  72 /*
  73  * General functions
  74  */
  75 static inline struct proc_inode *PROC_I(const struct inode *inode)
  76 {
  77         return container_of(inode, struct proc_inode, vfs_inode);
  78 }
  79
  80 static inline struct proc_dir_entry *PDE(const struct inode *inode)
  81 {
  82         return PROC_I(inode)->pde;
  83 }
  84
  85 static inline void *__PDE_DATA(const struct inode *inode)
  86 {
  87         return PDE(inode)->data;
  88 }
  89
  90 static inline struct pid *proc_pid(struct inode *inode)
  91 {
  92         return PROC_I(inode)->pid;
  93 }
  94
  95 static inline struct task_struct *get_proc_task(struct inode *inode)
  96 {
  97         return get_pid_task(proc_pid(inode), PIDTYPE_PID);
  98 }
  99
 100 static inline int task_dumpable(struct task_struct *task)
 101 {
 102         int dumpable = 0;
 103         struct mm_struct *mm;
 104
 105         task_lock(task);
 106         mm = task->mm;
 107         if (mm)
 108                 dumpable = get_dumpable(mm);
 109         task_unlock(task);
 110         if (dumpable == SUID_DUMP_USER)
 111                 return 1;
 112         return 0;
 113 }
 114
 115 static inline unsigned name_to_int(struct dentry *dentry)
 116 {
 117         const char *name = dentry->d_name.name;
 118         int len = dentry->d_name.len;
 119         unsigned n = 0;
 120
 121         if (len > 1 && *name == '0')
 122                 goto out;
 123         while (len-- > 0) {
 124                 unsigned c = *name++ - '0';
 125                 if (c > 9)
 126                         goto out;
 127                 if (n >= (~0U-9)/10)
 128                         goto out;
 129                 n *= 10;
 130                 n += c;
 131         }
 132         return n;
 133 out:
 134         return ~0U;
 135 }
 136
 137 /*
 138  * Offset of the first process in the /proc root directory..
 139  */
 140 #define FIRST_PROCESS_ENTRY 256
 141
 142 /* Worst case buffer size needed for holding an integer. */
 143 #define PROC_NUMBUF 13
 144
 145 /*
 146  * array.c
 147  */
 148 extern const struct file_operations proc_tid_children_operations;
 149
 150 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
 151                          struct pid *, struct task_struct *);
 152 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
 153                           struct pid *, struct task_struct *);
 154 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
 155                            struct pid *, struct task_struct *);
 156 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
 157                           struct pid *, struct task_struct *);
 158
 159 /*
 160  * base.c
 161  */
 162 extern const struct dentry_operations pid_dentry_operations;
 163 extern int pid_getattr(struct vfsmount *, struct dentry *, struct kstat *);
 164 extern int proc_setattr(struct dentry *, struct iattr *);
 165 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *);
 166 extern int pid_revalidate(struct dentry *, unsigned int);
 167 extern int pid_delete_dentry(const struct dentry *);
 168 extern int proc_pid_readdir(struct file *, struct dir_context *);
 169 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
 170 extern loff_t mem_lseek(struct file *, loff_t, int);
 171
 172 /* Lookups */
 173 typedef int instantiate_t(struct inode *, struct dentry *,
 174                                      struct task_struct *, const void *);
 175 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
 176                            instantiate_t, struct task_struct *, const void *);
 177
 178 /*
 179  * generic.c
 180  */
 181 extern spinlock_t proc_subdir_lock;
 182
 183 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
 184 extern struct dentry *proc_lookup_de(struct proc_dir_entry *, struct inode *,
 185                                      struct dentry *);
 186 extern int proc_readdir(struct file *, struct dir_context *);
 187 extern int proc_readdir_de(struct proc_dir_entry *, struct file *, struct dir_context *);
 188
 189 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
 190 {
 191         atomic_inc(&pde->count);
 192         return pde;
 193 }
 194 extern void pde_put(struct proc_dir_entry *);
 195
 196 /*
 197  * inode.c
 198  */
 199 struct pde_opener {
 200         struct file *file;
 201         struct list_head lh;
 202         int closing;
 203         struct completion *c;
 204 };
 205
 206 extern const struct inode_operations proc_pid_link_inode_operations;
 207
 208 extern void proc_init_inodecache(void);
 209 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
 210 extern int proc_fill_super(struct super_block *);
 211 extern void proc_entry_rundown(struct proc_dir_entry *);
 212
 213 /*
 214  * proc_namespaces.c
 215  */
 216 extern const struct inode_operations proc_ns_dir_inode_operations;
 217 extern const struct file_operations proc_ns_dir_operations;
 218
 219 /*
 220  * proc_net.c
 221  */
 222 extern const struct file_operations proc_net_operations;
 223 extern const struct inode_operations proc_net_inode_operations;
 224
 225 #ifdef CONFIG_NET
 226 extern int proc_net_init(void);
 227 #else
 228 static inline int proc_net_init(void) { return 0; }
 229 #endif
 230
 231 /*
 232  * proc_self.c
 233  */
 234 extern int proc_setup_self(struct super_block *);
 235
 236 /*
 237  * proc_sysctl.c
 238  */
 239 #ifdef CONFIG_PROC_SYSCTL
 240 extern int proc_sys_init(void);
 241 extern void sysctl_head_put(struct ctl_table_header *);
 242 #else
 243 static inline void proc_sys_init(void) { }
 244 static inline void sysctl_head_put(struct ctl_table_header *head) { }
 245 #endif
 246
 247 /*
 248  * proc_tty.c
 249  */
 250 #ifdef CONFIG_TTY
 251 extern void proc_tty_init(void);
 252 #else
 253 static inline void proc_tty_init(void) {}
 254 #endif
 255
 256 /*
 257  * root.c
 258  */
 259 extern struct proc_dir_entry proc_root;
 260
 261 extern void proc_self_init(void);
 262 extern int proc_remount(struct super_block *, int *, char *);
 263
 264 /*
 265  * task_[no]mmu.c
 266  */
 267 struct proc_maps_private {
 268         struct pid *pid;
 269         struct task_struct *task;
 270 #ifdef CONFIG_MMU
 271         struct vm_area_struct *tail_vma;
 272 #endif
 273 #ifdef CONFIG_NUMA
 274         struct mempolicy *task_mempolicy;
 275 #endif
 276 };
 277
 278 extern const struct file_operations proc_pid_maps_operations;
 279 extern const struct file_operations proc_tid_maps_operations;
 280 extern const struct file_operations proc_pid_numa_maps_operations;
 281 extern const struct file_operations proc_tid_numa_maps_operations;
 282 extern const struct file_operations proc_pid_smaps_operations;
 283 extern const struct file_operations proc_tid_smaps_operations;
 284 extern const struct file_operations proc_clear_refs_operations;
 285 extern const struct file_operations proc_pagemap_operations;
 286
 287 extern unsigned long task_vsize(struct mm_struct *);
 288 extern unsigned long task_statm(struct mm_struct *,
 289                                 unsigned long *, unsigned long *,
 290                                 unsigned long *, unsigned long *);
 291 extern void task_mem(struct seq_file *, struct mm_struct *);