include/linux/fsnotify.h

   1 #ifndef _LINUX_FS_NOTIFY_H
   2 #define _LINUX_FS_NOTIFY_H
   3
   4 /*
   5  * include/linux/fsnotify.h - generic hooks for filesystem notification, to
   6  * reduce in-source duplication from both dnotify and inotify.
   7  *
   8  * We don't compile any of this away in some complicated menagerie of ifdefs.
   9  * Instead, we rely on the code inside to optimize away as needed.
  10  *
  11  * (C) Copyright 2005 Robert Love
  12  */
  13
  14 #include <linux/dnotify.h>
  15 #include <linux/inotify.h>
  16 #include <linux/fsnotify_backend.h>
  17 #include <linux/audit.h>
  18 #include <linux/slab.h>
  19
  20 /*
  21  * fsnotify_d_instantiate - instantiate a dentry for inode
  22  * Called with dcache_lock held.
  23  */
  24 static inline void fsnotify_d_instantiate(struct dentry *entry,
  25                                                 struct inode *inode)
  26 {
  27         __fsnotify_d_instantiate(entry, inode);
  28
  29         inotify_d_instantiate(entry, inode);
  30 }
  31
  32 /* Notify this dentry's parent about a child's events. */
  33 static inline void fsnotify_parent(struct dentry *dentry, __u32 mask)
  34 {
  35         __fsnotify_parent(dentry, mask);
  36
  37         inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name);
  38 }
  39
  40 /*
  41  * fsnotify_d_move - entry has been moved
  42  * Called with dcache_lock and entry->d_lock held.
  43  */
  44 static inline void fsnotify_d_move(struct dentry *entry)
  45 {
  46         /*
  47          * On move we need to update entry->d_flags to indicate if the new parent
  48          * cares about events from this entry.
  49          */
  50         __fsnotify_update_dcache_flags(entry);
  51
  52         inotify_d_move(entry);
  53 }
  54
  55 /*
  56  * fsnotify_link_count - inode's link count changed
  57  */
  58 static inline void fsnotify_link_count(struct inode *inode)
  59 {
  60         inotify_inode_queue_event(inode, IN_ATTRIB, 0, NULL, NULL);
  61
  62         fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
  63 }
  64
  65 /*
  66  * fsnotify_move - file old_name at old_dir was moved to new_name at new_dir
  67  */
  68 static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir,
  69                                  const char *old_name,
  70                                  int isdir, struct inode *target, struct dentry *moved)
  71 {
  72         struct inode *source = moved->d_inode;
  73         u32 in_cookie = inotify_get_cookie();
  74         u32 fs_cookie = fsnotify_get_cookie();
  75         __u32 old_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_FROM);
  76         __u32 new_dir_mask = (FS_EVENT_ON_CHILD | FS_MOVED_TO);
  77         const char *new_name = moved->d_name.name;
  78
  79         if (old_dir == new_dir)
  80                 old_dir_mask |= FS_DN_RENAME;
  81
  82         if (isdir) {
  83                 isdir = IN_ISDIR;
  84                 old_dir_mask |= FS_IN_ISDIR;
  85                 new_dir_mask |= FS_IN_ISDIR;
  86         }
  87
  88         inotify_inode_queue_event(old_dir, IN_MOVED_FROM|isdir, in_cookie, old_name,
  89                                   source);
  90         inotify_inode_queue_event(new_dir, IN_MOVED_TO|isdir, in_cookie, new_name,
  91                                   source);
  92
  93         fsnotify(old_dir, old_dir_mask, old_dir, FSNOTIFY_EVENT_INODE, old_name, fs_cookie);
  94         fsnotify(new_dir, new_dir_mask, new_dir, FSNOTIFY_EVENT_INODE, new_name, fs_cookie);
  95
  96         if (target) {
  97                 inotify_inode_queue_event(target, IN_DELETE_SELF, 0, NULL, NULL);
  98                 inotify_inode_is_dead(target);
  99
 100                 /* this is really a link_count change not a removal */
 101                 fsnotify_link_count(target);
 102         }
 103
 104         if (source) {
 105                 inotify_inode_queue_event(source, IN_MOVE_SELF, 0, NULL, NULL);
 106                 fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0);
 107         }
 108         audit_inode_child(moved, new_dir);
 109 }
 110
 111 /*
 112  * fsnotify_inode_delete - and inode is being evicted from cache, clean up is needed
 113  */
 114 static inline void fsnotify_inode_delete(struct inode *inode)
 115 {
 116         __fsnotify_inode_delete(inode);
 117 }
 118
 119 /*
 120  * fsnotify_nameremove - a filename was removed from a directory
 121  */
 122 static inline void fsnotify_nameremove(struct dentry *dentry, int isdir)
 123 {
 124         __u32 mask = FS_DELETE;
 125
 126         if (isdir)
 127                 mask |= FS_IN_ISDIR;
 128
 129         fsnotify_parent(dentry, mask);
 130 }
 131
 132 /*
 133  * fsnotify_inoderemove - an inode is going away
 134  */
 135 static inline void fsnotify_inoderemove(struct inode *inode)
 136 {
 137         inotify_inode_queue_event(inode, IN_DELETE_SELF, 0, NULL, NULL);
 138         inotify_inode_is_dead(inode);
 139
 140         fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
 141         __fsnotify_inode_delete(inode);
 142 }
 143
 144 /*
 145  * fsnotify_create - 'name' was linked in
 146  */
 147 static inline void fsnotify_create(struct inode *inode, struct dentry *dentry)
 148 {
 149         inotify_inode_queue_event(inode, IN_CREATE, 0, dentry->d_name.name,
 150                                   dentry->d_inode);
 151         audit_inode_child(dentry, inode);
 152
 153         fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
 154 }
 155
 156 /*
 157  * fsnotify_link - new hardlink in 'inode' directory
 158  * Note: We have to pass also the linked inode ptr as some filesystems leave
 159  *   new_dentry->d_inode NULL and instantiate inode pointer later
 160  */
 161 static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry)
 162 {
 163         inotify_inode_queue_event(dir, IN_CREATE, 0, new_dentry->d_name.name,
 164                                   inode);
 165         fsnotify_link_count(inode);
 166         audit_inode_child(new_dentry, dir);
 167
 168         fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name, 0);
 169 }
 170
 171 /*
 172  * fsnotify_mkdir - directory 'name' was created
 173  */
 174 static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry)
 175 {
 176         __u32 mask = (FS_CREATE | FS_IN_ISDIR);
 177         struct inode *d_inode = dentry->d_inode;
 178
 179         inotify_inode_queue_event(inode, mask, 0, dentry->d_name.name, d_inode);
 180         audit_inode_child(dentry, inode);
 181
 182         fsnotify(inode, mask, d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
 183 }
 184
 185 /*
 186  * fsnotify_access - file was read
 187  */
 188 static inline void fsnotify_access(struct dentry *dentry)
 189 {
 190         struct inode *inode = dentry->d_inode;
 191         __u32 mask = FS_ACCESS;
 192
 193         if (S_ISDIR(inode->i_mode))
 194                 mask |= FS_IN_ISDIR;
 195
 196         inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
 197
 198         fsnotify_parent(dentry, mask);
 199         fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
 200 }
 201
 202 /*
 203  * fsnotify_modify - file was modified
 204  */
 205 static inline void fsnotify_modify(struct dentry *dentry)
 206 {
 207         struct inode *inode = dentry->d_inode;
 208         __u32 mask = FS_MODIFY;
 209
 210         if (S_ISDIR(inode->i_mode))
 211                 mask |= FS_IN_ISDIR;
 212
 213         inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
 214
 215         fsnotify_parent(dentry, mask);
 216         fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
 217 }
 218
 219 /*
 220  * fsnotify_open - file was opened
 221  */
 222 static inline void fsnotify_open(struct dentry *dentry)
 223 {
 224         struct inode *inode = dentry->d_inode;
 225         __u32 mask = FS_OPEN;
 226
 227         if (S_ISDIR(inode->i_mode))
 228                 mask |= FS_IN_ISDIR;
 229
 230         inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
 231
 232         fsnotify_parent(dentry, mask);
 233         fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
 234 }
 235
 236 /*
 237  * fsnotify_close - file was closed
 238  */
 239 static inline void fsnotify_close(struct file *file)
 240 {
 241         struct dentry *dentry = file->f_path.dentry;
 242         struct inode *inode = dentry->d_inode;
 243         fmode_t mode = file->f_mode;
 244         __u32 mask = (mode & FMODE_WRITE) ? FS_CLOSE_WRITE : FS_CLOSE_NOWRITE;
 245
 246         if (S_ISDIR(inode->i_mode))
 247                 mask |= FS_IN_ISDIR;
 248
 249         inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
 250
 251         fsnotify_parent(dentry, mask);
 252         fsnotify(inode, mask, file, FSNOTIFY_EVENT_FILE, NULL, 0);
 253 }
 254
 255 /*
 256  * fsnotify_xattr - extended attributes were changed
 257  */
 258 static inline void fsnotify_xattr(struct dentry *dentry)
 259 {
 260         struct inode *inode = dentry->d_inode;
 261         __u32 mask = FS_ATTRIB;
 262
 263         if (S_ISDIR(inode->i_mode))
 264                 mask |= FS_IN_ISDIR;
 265
 266         inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
 267
 268         fsnotify_parent(dentry, mask);
 269         fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
 270 }
 271
 272 /*
 273  * fsnotify_change - notify_change event.  file was modified and/or metadata
 274  * was changed.
 275  */
 276 static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid)
 277 {
 278         struct inode *inode = dentry->d_inode;
 279         __u32 mask = 0;
 280
 281         if (ia_valid & ATTR_UID)
 282                 mask |= FS_ATTRIB;
 283         if (ia_valid & ATTR_GID)
 284                 mask |= FS_ATTRIB;
 285         if (ia_valid & ATTR_SIZE)
 286                 mask |= FS_MODIFY;
 287
 288         /* both times implies a utime(s) call */
 289         if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME))
 290                 mask |= FS_ATTRIB;
 291         else if (ia_valid & ATTR_ATIME)
 292                 mask |= FS_ACCESS;
 293         else if (ia_valid & ATTR_MTIME)
 294                 mask |= FS_MODIFY;
 295
 296         if (ia_valid & ATTR_MODE)
 297                 mask |= FS_ATTRIB;
 298
 299         if (mask) {
 300                 if (S_ISDIR(inode->i_mode))
 301                         mask |= FS_IN_ISDIR;
 302                 inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
 303
 304                 fsnotify_parent(dentry, mask);
 305                 fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
 306         }
 307 }
 308
 309 #if defined(CONFIG_INOTIFY) || defined(CONFIG_FSNOTIFY) /* notify helpers */
 310
 311 /*
 312  * fsnotify_oldname_init - save off the old filename before we change it
 313  */
 314 static inline const char *fsnotify_oldname_init(const char *name)
 315 {
 316         return kstrdup(name, GFP_KERNEL);
 317 }
 318
 319 /*
 320  * fsnotify_oldname_free - free the name we got from fsnotify_oldname_init
 321  */
 322 static inline void fsnotify_oldname_free(const char *old_name)
 323 {
 324         kfree(old_name);
 325 }
 326
 327 #else   /* CONFIG_INOTIFY || CONFIG_FSNOTIFY */
 328
 329 static inline const char *fsnotify_oldname_init(const char *name)
 330 {
 331         return NULL;
 332 }
 333
 334 static inline void fsnotify_oldname_free(const char *old_name)
 335 {
 336 }
 337
 338 #endif  /* ! CONFIG_INOTIFY */
 339
 340 #endif  /* _LINUX_FS_NOTIFY_H */