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  * parent/subdir are used for the directory structure (every /proc file has a
  28  * parent, but "subdir" is empty for all non-directory entries).
  29  * subdir_node is used to build the rb tree "subdir" of the parent.
  30  */
  31 struct proc_dir_entry {
  32         unsigned int low_ino;
  33         umode_t mode;
  34         nlink_t nlink;
  35         kuid_t uid;
  36         kgid_t gid;
  37         loff_t size;
  38         const struct inode_operations *proc_iops;
  39         const struct file_operations *proc_fops;
  40         struct proc_dir_entry *parent;
  41         struct rb_root subdir;
  42         struct rb_node subdir_node;
  43         void *data;
  44         atomic_t count;         /* use count */
  45         atomic_t in_use;        /* number of callers into module in progress; */
  46                         /* negative -> it's going away RSN */
  47         struct completion *pde_unload_completion;
  48         struct list_head pde_openers;   /* who did ->open, but not ->release */
  49         spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
  50         u8 namelen;
  51         char name[];
  52 };
  53
  54 union proc_op {
  55         int (*proc_get_link)(struct dentry *, struct path *);
  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         unsigned 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         const struct proc_ns_operations *ns_ops;
  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 void task_dump_owner(struct task_struct *task, mode_t mode,
 101                      kuid_t *ruid, kgid_t *rgid);
 102
 103 static inline unsigned name_to_int(const struct qstr *qstr)
 104 {
 105         const char *name = qstr->name;
 106         int len = qstr->len;
 107         unsigned n = 0;
 108
 109         if (len > 1 && *name == '0')
 110                 goto out;
 111         while (len-- > 0) {
 112                 unsigned c = *name++ - '0';
 113                 if (c > 9)
 114                         goto out;
 115                 if (n >= (~0U-9)/10)
 116                         goto out;
 117                 n *= 10;
 118                 n += c;
 119         }
 120         return n;
 121 out:
 122         return ~0U;
 123 }
 124
 125 /*
 126  * Offset of the first process in the /proc root directory..
 127  */
 128 #define FIRST_PROCESS_ENTRY 256
 129
 130 /* Worst case buffer size needed for holding an integer. */
 131 #define PROC_NUMBUF 13
 132
 133 /*
 134  * array.c
 135  */
 136 extern const struct file_operations proc_tid_children_operations;
 137
 138 extern int proc_tid_stat(struct seq_file *, struct pid_namespace *,
 139                          struct pid *, struct task_struct *);
 140 extern int proc_tgid_stat(struct seq_file *, struct pid_namespace *,
 141                           struct pid *, struct task_struct *);
 142 extern int proc_pid_status(struct seq_file *, struct pid_namespace *,
 143                            struct pid *, struct task_struct *);
 144 extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
 145                           struct pid *, struct task_struct *);
 146
 147 /*
 148  * base.c
 149  */
 150 extern const struct dentry_operations pid_dentry_operations;
 151 extern int pid_getattr(struct vfsmount *, struct dentry *, struct kstat *);
 152 extern int proc_setattr(struct dentry *, struct iattr *);
 153 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
 154 extern int pid_revalidate(struct dentry *, unsigned int);
 155 extern int pid_delete_dentry(const struct dentry *);
 156 extern int proc_pid_readdir(struct file *, struct dir_context *);
 157 extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
 158 extern loff_t mem_lseek(struct file *, loff_t, int);
 159
 160 /* Lookups */
 161 typedef int instantiate_t(struct inode *, struct dentry *,
 162                                      struct task_struct *, const void *);
 163 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
 164                            instantiate_t, struct task_struct *, const void *);
 165
 166 /*
 167  * generic.c
 168  */
 169 extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int);
 170 extern struct dentry *proc_lookup_de(struct proc_dir_entry *, struct inode *,
 171                                      struct dentry *);
 172 extern int proc_readdir(struct file *, struct dir_context *);
 173 extern int proc_readdir_de(struct proc_dir_entry *, struct file *, struct dir_context *);
 174
 175 static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
 176 {
 177         atomic_inc(&pde->count);
 178         return pde;
 179 }
 180 extern void pde_put(struct proc_dir_entry *);
 181
 182 static inline bool is_empty_pde(const struct proc_dir_entry *pde)
 183 {
 184         return S_ISDIR(pde->mode) && !pde->proc_iops;
 185 }
 186
 187 /*
 188  * inode.c
 189  */
 190 struct pde_opener {
 191         struct file *file;
 192         struct list_head lh;
 193         bool closing;
 194         struct completion *c;
 195 };
 196 extern const struct inode_operations proc_link_inode_operations;
 197
 198 extern const struct inode_operations proc_pid_link_inode_operations;
 199
 200 extern void proc_init_inodecache(void);
 201 void set_proc_pid_nlink(void);
 202 extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
 203 extern int proc_fill_super(struct super_block *, void *data, int flags);
 204 extern void proc_entry_rundown(struct proc_dir_entry *);
 205
 206 /*
 207  * proc_namespaces.c
 208  */
 209 extern const struct inode_operations proc_ns_dir_inode_operations;
 210 extern const struct file_operations proc_ns_dir_operations;
 211
 212 /*
 213  * proc_net.c
 214  */
 215 extern const struct file_operations proc_net_operations;
 216 extern const struct inode_operations proc_net_inode_operations;
 217
 218 #ifdef CONFIG_NET
 219 extern int proc_net_init(void);
 220 #else
 221 static inline int proc_net_init(void) { return 0; }
 222 #endif
 223
 224 /*
 225  * proc_self.c
 226  */
 227 extern int proc_setup_self(struct super_block *);
 228
 229 /*
 230  * proc_thread_self.c
 231  */
 232 extern int proc_setup_thread_self(struct super_block *);
 233 extern void proc_thread_self_init(void);
 234
 235 /*
 236  * proc_sysctl.c
 237  */
 238 #ifdef CONFIG_PROC_SYSCTL
 239 extern int proc_sys_init(void);
 240 extern void sysctl_head_put(struct ctl_table_header *);
 241 #else
 242 static inline void proc_sys_init(void) { }
 243 static inline void sysctl_head_put(struct ctl_table_header *head) { }
 244 #endif
 245
 246 /*
 247  * proc_tty.c
 248  */
 249 #ifdef CONFIG_TTY
 250 extern void proc_tty_init(void);
 251 #else
 252 static inline void proc_tty_init(void) {}
 253 #endif
 254
 255 /*
 256  * root.c
 257  */
 258 extern struct proc_dir_entry proc_root;
 259 extern int proc_parse_options(char *options, struct pid_namespace *pid);
 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 inode *inode;
 269         struct task_struct *task;
 270         struct mm_struct *mm;
 271 #ifdef CONFIG_MMU
 272         struct vm_area_struct *tail_vma;
 273 #endif
 274 #ifdef CONFIG_NUMA
 275         struct mempolicy *task_mempolicy;
 276 #endif
 277 };
 278
 279 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);
 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 *);