fs/aufs/inode.h

   1 /*
   2  * Copyright (C) 2005-2016 Junjiro R. Okajima
   3  *
   4  * This program, aufs is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 /*
  19  * inode operations
  20  */
  21
  22 #ifndef __AUFS_INODE_H__
  23 #define __AUFS_INODE_H__
  24
  25 #ifdef __KERNEL__
  26
  27 #include <linux/fsnotify.h>
  28 #include "rwsem.h"
  29
  30 struct vfsmount;
  31
  32 struct au_hnotify {
  33 #ifdef CONFIG_AUFS_HNOTIFY
  34 #ifdef CONFIG_AUFS_HFSNOTIFY
  35         /* never use fsnotify_add_vfsmount_mark() */
  36         struct fsnotify_mark            hn_mark;
  37 #endif
  38         union {
  39                 struct inode            *hn_aufs_inode; /* no get/put */
  40                 struct llist_node       hn_lnode;       /* delayed free */
  41         };
  42 #endif
  43 } ____cacheline_aligned_in_smp;
  44
  45 struct au_hinode {
  46         struct inode            *hi_inode;
  47         aufs_bindex_t           hi_id;
  48 #ifdef CONFIG_AUFS_HNOTIFY
  49         struct au_hnotify       *hi_notify;
  50 #endif
  51
  52         /* reference to the copied-up whiteout with get/put */
  53         struct dentry           *hi_whdentry;
  54 };
  55
  56 /* ig_flags */
  57 #define AuIG_HALF_REFRESHED             1
  58 #define au_ig_ftest(flags, name)        ((flags) & AuIG_##name)
  59 #define au_ig_fset(flags, name) \
  60         do { (flags) |= AuIG_##name; } while (0)
  61 #define au_ig_fclr(flags, name) \
  62         do { (flags) &= ~AuIG_##name; } while (0)
  63
  64 struct au_iigen {
  65         spinlock_t      ig_spin;
  66         __u32           ig_generation, ig_flags;
  67 };
  68
  69 struct au_vdir;
  70 struct au_iinfo {
  71         struct au_iigen         ii_generation;
  72         struct super_block      *ii_hsb1;       /* no get/put */
  73
  74         struct au_rwsem         ii_rwsem;
  75         aufs_bindex_t           ii_btop, ii_bbot;
  76         __u32                   ii_higen;
  77         struct au_hinode        *ii_hinode;
  78         struct au_vdir          *ii_vdir;
  79 };
  80
  81 struct au_icntnr {
  82         struct au_iinfo iinfo;
  83         struct inode vfs_inode;
  84         union {
  85                 struct hlist_node       plink;
  86                 struct llist_node       lnode;  /* delayed free */
  87         };
  88 } ____cacheline_aligned_in_smp;
  89
  90 /* au_pin flags */
  91 #define AuPin_DI_LOCKED         1
  92 #define AuPin_MNT_WRITE         (1 << 1)
  93 #define au_ftest_pin(flags, name)       ((flags) & AuPin_##name)
  94 #define au_fset_pin(flags, name) \
  95         do { (flags) |= AuPin_##name; } while (0)
  96 #define au_fclr_pin(flags, name) \
  97         do { (flags) &= ~AuPin_##name; } while (0)
  98
  99 struct au_pin {
 100         /* input */
 101         struct dentry *dentry;
 102         unsigned int udba;
 103         unsigned char lsc_di, lsc_hi, flags;
 104         aufs_bindex_t bindex;
 105
 106         /* output */
 107         struct dentry *parent;
 108         struct au_hinode *hdir;
 109         struct vfsmount *h_mnt;
 110
 111         /* temporary unlock/relock for copyup */
 112         struct dentry *h_dentry, *h_parent;
 113         struct au_branch *br;
 114         struct task_struct *task;
 115 };
 116
 117 void au_pin_hdir_unlock(struct au_pin *p);
 118 int au_pin_hdir_lock(struct au_pin *p);
 119 int au_pin_hdir_relock(struct au_pin *p);
 120 void au_pin_hdir_acquire_nest(struct au_pin *p);
 121 void au_pin_hdir_release(struct au_pin *p);
 122
 123 /* ---------------------------------------------------------------------- */
 124
 125 static inline struct au_iinfo *au_ii(struct inode *inode)
 126 {
 127         BUG_ON(is_bad_inode(inode));
 128         return &(container_of(inode, struct au_icntnr, vfs_inode)->iinfo);
 129 }
 130
 131 /* ---------------------------------------------------------------------- */
 132
 133 /* inode.c */
 134 struct inode *au_igrab(struct inode *inode);
 135 void au_refresh_iop(struct inode *inode, int force_getattr);
 136 int au_refresh_hinode_self(struct inode *inode);
 137 int au_refresh_hinode(struct inode *inode, struct dentry *dentry);
 138 int au_ino(struct super_block *sb, aufs_bindex_t bindex, ino_t h_ino,
 139            unsigned int d_type, ino_t *ino);
 140 struct inode *au_new_inode(struct dentry *dentry, int must_new);
 141 int au_test_ro(struct super_block *sb, aufs_bindex_t bindex,
 142                struct inode *inode);
 143 int au_test_h_perm(struct inode *h_inode, int mask);
 144 int au_test_h_perm_sio(struct inode *h_inode, int mask);
 145
 146 static inline int au_wh_ino(struct super_block *sb, aufs_bindex_t bindex,
 147                             ino_t h_ino, unsigned int d_type, ino_t *ino)
 148 {
 149 #ifdef CONFIG_AUFS_SHWH
 150         return au_ino(sb, bindex, h_ino, d_type, ino);
 151 #else
 152         return 0;
 153 #endif
 154 }
 155
 156 /* i_op.c */
 157 enum {
 158         AuIop_SYMLINK,
 159         AuIop_DIR,
 160         AuIop_OTHER,
 161         AuIop_Last
 162 };
 163 extern struct inode_operations aufs_iop[AuIop_Last],
 164         aufs_iop_nogetattr[AuIop_Last];
 165
 166 /* au_wr_dir flags */
 167 #define AuWrDir_ADD_ENTRY       1
 168 #define AuWrDir_ISDIR           (1 << 1)
 169 #define AuWrDir_TMPFILE         (1 << 2)
 170 #define au_ftest_wrdir(flags, name)     ((flags) & AuWrDir_##name)
 171 #define au_fset_wrdir(flags, name) \
 172         do { (flags) |= AuWrDir_##name; } while (0)
 173 #define au_fclr_wrdir(flags, name) \
 174         do { (flags) &= ~AuWrDir_##name; } while (0)
 175
 176 struct au_wr_dir_args {
 177         aufs_bindex_t force_btgt;
 178         unsigned char flags;
 179 };
 180 int au_wr_dir(struct dentry *dentry, struct dentry *src_dentry,
 181               struct au_wr_dir_args *args);
 182
 183 struct dentry *au_pinned_h_parent(struct au_pin *pin);
 184 void au_pin_init(struct au_pin *pin, struct dentry *dentry,
 185                  aufs_bindex_t bindex, int lsc_di, int lsc_hi,
 186                  unsigned int udba, unsigned char flags);
 187 int au_pin(struct au_pin *pin, struct dentry *dentry, aufs_bindex_t bindex,
 188            unsigned int udba, unsigned char flags) __must_check;
 189 int au_do_pin(struct au_pin *pin) __must_check;
 190 void au_unpin(struct au_pin *pin);
 191 int au_reval_for_attr(struct dentry *dentry, unsigned int sigen);
 192
 193 #define AuIcpup_DID_CPUP        1
 194 #define au_ftest_icpup(flags, name)     ((flags) & AuIcpup_##name)
 195 #define au_fset_icpup(flags, name) \
 196         do { (flags) |= AuIcpup_##name; } while (0)
 197 #define au_fclr_icpup(flags, name) \
 198         do { (flags) &= ~AuIcpup_##name; } while (0)
 199
 200 struct au_icpup_args {
 201         unsigned char flags;
 202         unsigned char pin_flags;
 203         aufs_bindex_t btgt;
 204         unsigned int udba;
 205         struct au_pin pin;
 206         struct path h_path;
 207         struct inode *h_inode;
 208 };
 209
 210 int au_pin_and_icpup(struct dentry *dentry, struct iattr *ia,
 211                      struct au_icpup_args *a);
 212
 213 int au_h_path_getattr(struct dentry *dentry, int force, struct path *h_path,
 214                       int locked);
 215
 216 /* i_op_add.c */
 217 int au_may_add(struct dentry *dentry, aufs_bindex_t bindex,
 218                struct dentry *h_parent, int isdir);
 219 int aufs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
 220                dev_t dev);
 221 int aufs_symlink(struct inode *dir, struct dentry *dentry, const char *symname);
 222 int aufs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 223                 bool want_excl);
 224 struct vfsub_aopen_args;
 225 int au_aopen_or_create(struct inode *dir, struct dentry *dentry,
 226                        struct vfsub_aopen_args *args);
 227 int aufs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode);
 228 int aufs_link(struct dentry *src_dentry, struct inode *dir,
 229               struct dentry *dentry);
 230 int aufs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode);
 231
 232 /* i_op_del.c */
 233 int au_wr_dir_need_wh(struct dentry *dentry, int isdir, aufs_bindex_t *bcpup);
 234 int au_may_del(struct dentry *dentry, aufs_bindex_t bindex,
 235                struct dentry *h_parent, int isdir);
 236 int aufs_unlink(struct inode *dir, struct dentry *dentry);
 237 int aufs_rmdir(struct inode *dir, struct dentry *dentry);
 238
 239 /* i_op_ren.c */
 240 int au_wbr(struct dentry *dentry, aufs_bindex_t btgt);
 241 int aufs_rename(struct inode *src_dir, struct dentry *src_dentry,
 242                 struct inode *dir, struct dentry *dentry,
 243                 unsigned int flags);
 244
 245 /* iinfo.c */
 246 struct inode *au_h_iptr(struct inode *inode, aufs_bindex_t bindex);
 247 void au_hiput(struct au_hinode *hinode);
 248 void au_set_hi_wh(struct inode *inode, aufs_bindex_t bindex,
 249                   struct dentry *h_wh);
 250 unsigned int au_hi_flags(struct inode *inode, int isdir);
 251
 252 /* hinode flags */
 253 #define AuHi_XINO       1
 254 #define AuHi_HNOTIFY    (1 << 1)
 255 #define au_ftest_hi(flags, name)        ((flags) & AuHi_##name)
 256 #define au_fset_hi(flags, name) \
 257         do { (flags) |= AuHi_##name; } while (0)
 258 #define au_fclr_hi(flags, name) \
 259         do { (flags) &= ~AuHi_##name; } while (0)
 260
 261 #ifndef CONFIG_AUFS_HNOTIFY
 262 #undef AuHi_HNOTIFY
 263 #define AuHi_HNOTIFY    0
 264 #endif
 265
 266 void au_set_h_iptr(struct inode *inode, aufs_bindex_t bindex,
 267                    struct inode *h_inode, unsigned int flags);
 268
 269 void au_update_iigen(struct inode *inode, int half);
 270 void au_update_ibrange(struct inode *inode, int do_put_zero);
 271
 272 void au_icntnr_init_once(void *_c);
 273 void au_hinode_init(struct au_hinode *hinode);
 274 int au_iinfo_init(struct inode *inode);
 275 void au_iinfo_fin(struct inode *inode);
 276 int au_hinode_realloc(struct au_iinfo *iinfo, int nbr, int may_shrink);
 277
 278 #ifdef CONFIG_PROC_FS
 279 /* plink.c */
 280 int au_plink_maint(struct super_block *sb, int flags);
 281 struct au_sbinfo;
 282 void au_plink_maint_leave(struct au_sbinfo *sbinfo);
 283 int au_plink_maint_enter(struct super_block *sb);
 284 #ifdef CONFIG_AUFS_DEBUG
 285 void au_plink_list(struct super_block *sb);
 286 #else
 287 AuStubVoid(au_plink_list, struct super_block *sb)
 288 #endif
 289 int au_plink_test(struct inode *inode);
 290 struct dentry *au_plink_lkup(struct inode *inode, aufs_bindex_t bindex);
 291 void au_plink_append(struct inode *inode, aufs_bindex_t bindex,
 292                      struct dentry *h_dentry);
 293 void au_plink_put(struct super_block *sb, int verbose);
 294 void au_plink_clean(struct super_block *sb, int verbose);
 295 void au_plink_half_refresh(struct super_block *sb, aufs_bindex_t br_id);
 296 #else
 297 AuStubInt0(au_plink_maint, struct super_block *sb, int flags);
 298 AuStubVoid(au_plink_maint_leave, struct au_sbinfo *sbinfo);
 299 AuStubInt0(au_plink_maint_enter, struct super_block *sb);
 300 AuStubVoid(au_plink_list, struct super_block *sb);
 301 AuStubInt0(au_plink_test, struct inode *inode);
 302 AuStub(struct dentry *, au_plink_lkup, return NULL,
 303        struct inode *inode, aufs_bindex_t bindex);
 304 AuStubVoid(au_plink_append, struct inode *inode, aufs_bindex_t bindex,
 305            struct dentry *h_dentry);
 306 AuStubVoid(au_plink_put, struct super_block *sb, int verbose);
 307 AuStubVoid(au_plink_clean, struct super_block *sb, int verbose);
 308 AuStubVoid(au_plink_half_refresh, struct super_block *sb, aufs_bindex_t br_id);
 309 #endif /* CONFIG_PROC_FS */
 310
 311 #ifdef CONFIG_AUFS_XATTR
 312 /* xattr.c */
 313 int au_cpup_xattr(struct dentry *h_dst, struct dentry *h_src, int ignore_flags,
 314                   unsigned int verbose);
 315 ssize_t aufs_listxattr(struct dentry *dentry, char *list, size_t size);
 316 void au_xattr_init(struct super_block *sb);
 317 #else
 318 AuStubInt0(au_cpup_xattr, struct dentry *h_dst, struct dentry *h_src,
 319            int ignore_flags, unsigned int verbose);
 320 AuStubVoid(au_xattr_init, struct super_block *sb);
 321 #endif
 322
 323 #ifdef CONFIG_FS_POSIX_ACL
 324 struct posix_acl *aufs_get_acl(struct inode *inode, int type);
 325 int aufs_set_acl(struct inode *inode, struct posix_acl *acl, int type);
 326 #endif
 327
 328 #if IS_ENABLED(CONFIG_AUFS_XATTR) || IS_ENABLED(CONFIG_FS_POSIX_ACL)
 329 enum {
 330         AU_XATTR_SET,
 331         AU_ACL_SET
 332 };
 333
 334 struct au_sxattr {
 335         int type;
 336         union {
 337                 struct {
 338                         const char      *name;
 339                         const void      *value;
 340                         size_t          size;
 341                         int             flags;
 342                 } set;
 343                 struct {
 344                         struct posix_acl *acl;
 345                         int             type;
 346                 } acl_set;
 347         } u;
 348 };
 349 ssize_t au_sxattr(struct dentry *dentry, struct inode *inode,
 350                   struct au_sxattr *arg);
 351 #endif
 352
 353 /* ---------------------------------------------------------------------- */
 354
 355 /* lock subclass for iinfo */
 356 enum {
 357         AuLsc_II_CHILD,         /* child first */
 358         AuLsc_II_CHILD2,        /* rename(2), link(2), and cpup at hnotify */
 359         AuLsc_II_CHILD3,        /* copyup dirs */
 360         AuLsc_II_PARENT,        /* see AuLsc_I_PARENT in vfsub.h */
 361         AuLsc_II_PARENT2,
 362         AuLsc_II_PARENT3,       /* copyup dirs */
 363         AuLsc_II_NEW_CHILD
 364 };
 365
 366 /*
 367  * ii_read_lock_child, ii_write_lock_child,
 368  * ii_read_lock_child2, ii_write_lock_child2,
 369  * ii_read_lock_child3, ii_write_lock_child3,
 370  * ii_read_lock_parent, ii_write_lock_parent,
 371  * ii_read_lock_parent2, ii_write_lock_parent2,
 372  * ii_read_lock_parent3, ii_write_lock_parent3,
 373  * ii_read_lock_new_child, ii_write_lock_new_child,
 374  */
 375 #define AuReadLockFunc(name, lsc) \
 376 static inline void ii_read_lock_##name(struct inode *i) \
 377 { \
 378         au_rw_read_lock_nested(&au_ii(i)->ii_rwsem, AuLsc_II_##lsc); \
 379 }
 380
 381 #define AuWriteLockFunc(name, lsc) \
 382 static inline void ii_write_lock_##name(struct inode *i) \
 383 { \
 384         au_rw_write_lock_nested(&au_ii(i)->ii_rwsem, AuLsc_II_##lsc); \
 385 }
 386
 387 #define AuRWLockFuncs(name, lsc) \
 388         AuReadLockFunc(name, lsc) \
 389         AuWriteLockFunc(name, lsc)
 390
 391 AuRWLockFuncs(child, CHILD);
 392 AuRWLockFuncs(child2, CHILD2);
 393 AuRWLockFuncs(child3, CHILD3);
 394 AuRWLockFuncs(parent, PARENT);
 395 AuRWLockFuncs(parent2, PARENT2);
 396 AuRWLockFuncs(parent3, PARENT3);
 397 AuRWLockFuncs(new_child, NEW_CHILD);
 398
 399 #undef AuReadLockFunc
 400 #undef AuWriteLockFunc
 401 #undef AuRWLockFuncs
 402
 403 /*
 404  * ii_read_unlock, ii_write_unlock, ii_downgrade_lock
 405  */
 406 AuSimpleUnlockRwsemFuncs(ii, struct inode *i, &au_ii(i)->ii_rwsem);
 407
 408 #define IiMustNoWaiters(i)      AuRwMustNoWaiters(&au_ii(i)->ii_rwsem)
 409 #define IiMustAnyLock(i)        AuRwMustAnyLock(&au_ii(i)->ii_rwsem)
 410 #define IiMustWriteLock(i)      AuRwMustWriteLock(&au_ii(i)->ii_rwsem)
 411
 412 /* ---------------------------------------------------------------------- */
 413
 414 static inline void au_icntnr_init(struct au_icntnr *c)
 415 {
 416 #ifdef CONFIG_AUFS_DEBUG
 417         c->vfs_inode.i_mode = 0;
 418 #endif
 419 }
 420
 421 static inline unsigned int au_iigen(struct inode *inode, unsigned int *igflags)
 422 {
 423         unsigned int gen;
 424         struct au_iinfo *iinfo;
 425         struct au_iigen *iigen;
 426
 427         iinfo = au_ii(inode);
 428         iigen = &iinfo->ii_generation;
 429         spin_lock(&iigen->ig_spin);
 430         if (igflags)
 431                 *igflags = iigen->ig_flags;
 432         gen = iigen->ig_generation;
 433         spin_unlock(&iigen->ig_spin);
 434
 435         return gen;
 436 }
 437
 438 /* tiny test for inode number */
 439 /* tmpfs generation is too rough */
 440 static inline int au_test_higen(struct inode *inode, struct inode *h_inode)
 441 {
 442         struct au_iinfo *iinfo;
 443
 444         iinfo = au_ii(inode);
 445         AuRwMustAnyLock(&iinfo->ii_rwsem);
 446         return !(iinfo->ii_hsb1 == h_inode->i_sb
 447                  && iinfo->ii_higen == h_inode->i_generation);
 448 }
 449
 450 static inline void au_iigen_dec(struct inode *inode)
 451 {
 452         struct au_iinfo *iinfo;
 453         struct au_iigen *iigen;
 454
 455         iinfo = au_ii(inode);
 456         iigen = &iinfo->ii_generation;
 457         spin_lock(&iigen->ig_spin);
 458         iigen->ig_generation--;
 459         spin_unlock(&iigen->ig_spin);
 460 }
 461
 462 static inline int au_iigen_test(struct inode *inode, unsigned int sigen)
 463 {
 464         int err;
 465
 466         err = 0;
 467         if (unlikely(inode && au_iigen(inode, NULL) != sigen))
 468                 err = -EIO;
 469
 470         return err;
 471 }
 472
 473 /* ---------------------------------------------------------------------- */
 474
 475 static inline struct au_hinode *au_hinode(struct au_iinfo *iinfo,
 476                                           aufs_bindex_t bindex)
 477 {
 478         return iinfo->ii_hinode + bindex;
 479 }
 480
 481 static inline int au_is_bad_inode(struct inode *inode)
 482 {
 483         return !!(is_bad_inode(inode) || !au_hinode(au_ii(inode), 0));
 484 }
 485
 486 static inline aufs_bindex_t au_ii_br_id(struct inode *inode,
 487                                         aufs_bindex_t bindex)
 488 {
 489         IiMustAnyLock(inode);
 490         return au_hinode(au_ii(inode), bindex)->hi_id;
 491 }
 492
 493 static inline aufs_bindex_t au_ibtop(struct inode *inode)
 494 {
 495         IiMustAnyLock(inode);
 496         return au_ii(inode)->ii_btop;
 497 }
 498
 499 static inline aufs_bindex_t au_ibbot(struct inode *inode)
 500 {
 501         IiMustAnyLock(inode);
 502         return au_ii(inode)->ii_bbot;
 503 }
 504
 505 static inline struct au_vdir *au_ivdir(struct inode *inode)
 506 {
 507         IiMustAnyLock(inode);
 508         return au_ii(inode)->ii_vdir;
 509 }
 510
 511 static inline struct dentry *au_hi_wh(struct inode *inode, aufs_bindex_t bindex)
 512 {
 513         IiMustAnyLock(inode);
 514         return au_hinode(au_ii(inode), bindex)->hi_whdentry;
 515 }
 516
 517 static inline void au_set_ibtop(struct inode *inode, aufs_bindex_t bindex)
 518 {
 519         IiMustWriteLock(inode);
 520         au_ii(inode)->ii_btop = bindex;
 521 }
 522
 523 static inline void au_set_ibbot(struct inode *inode, aufs_bindex_t bindex)
 524 {
 525         IiMustWriteLock(inode);
 526         au_ii(inode)->ii_bbot = bindex;
 527 }
 528
 529 static inline void au_set_ivdir(struct inode *inode, struct au_vdir *vdir)
 530 {
 531         IiMustWriteLock(inode);
 532         au_ii(inode)->ii_vdir = vdir;
 533 }
 534
 535 static inline struct au_hinode *au_hi(struct inode *inode, aufs_bindex_t bindex)
 536 {
 537         IiMustAnyLock(inode);
 538         return au_hinode(au_ii(inode), bindex);
 539 }
 540
 541 /* ---------------------------------------------------------------------- */
 542
 543 static inline struct dentry *au_pinned_parent(struct au_pin *pin)
 544 {
 545         if (pin)
 546                 return pin->parent;
 547         return NULL;
 548 }
 549
 550 static inline struct inode *au_pinned_h_dir(struct au_pin *pin)
 551 {
 552         if (pin && pin->hdir)
 553                 return pin->hdir->hi_inode;
 554         return NULL;
 555 }
 556
 557 static inline struct au_hinode *au_pinned_hdir(struct au_pin *pin)
 558 {
 559         if (pin)
 560                 return pin->hdir;
 561         return NULL;
 562 }
 563
 564 static inline void au_pin_set_dentry(struct au_pin *pin, struct dentry *dentry)
 565 {
 566         if (pin)
 567                 pin->dentry = dentry;
 568 }
 569
 570 static inline void au_pin_set_parent_lflag(struct au_pin *pin,
 571                                            unsigned char lflag)
 572 {
 573         if (pin) {
 574                 if (lflag)
 575                         au_fset_pin(pin->flags, DI_LOCKED);
 576                 else
 577                         au_fclr_pin(pin->flags, DI_LOCKED);
 578         }
 579 }
 580
 581 #if 0 /* reserved */
 582 static inline void au_pin_set_parent(struct au_pin *pin, struct dentry *parent)
 583 {
 584         if (pin) {
 585                 dput(pin->parent);
 586                 pin->parent = dget(parent);
 587         }
 588 }
 589 #endif
 590
 591 /* ---------------------------------------------------------------------- */
 592
 593 struct au_branch;
 594 #ifdef CONFIG_AUFS_HNOTIFY
 595 struct au_hnotify_op {
 596         void (*ctl)(struct au_hinode *hinode, int do_set);
 597         int (*alloc)(struct au_hinode *hinode);
 598
 599         /*
 600          * if it returns true, the the caller should free hinode->hi_notify,
 601          * otherwise ->free() frees it.
 602          */
 603         int (*free)(struct au_hinode *hinode,
 604                     struct au_hnotify *hn) __must_check;
 605
 606         void (*fin)(void);
 607         int (*init)(void);
 608
 609         int (*reset_br)(unsigned int udba, struct au_branch *br, int perm);
 610         void (*fin_br)(struct au_branch *br);
 611         int (*init_br)(struct au_branch *br, int perm);
 612 };
 613
 614 /* hnotify.c */
 615 int au_hn_alloc(struct au_hinode *hinode, struct inode *inode);
 616 void au_hn_free(struct au_hinode *hinode);
 617 void au_hn_ctl(struct au_hinode *hinode, int do_set);
 618 void au_hn_reset(struct inode *inode, unsigned int flags);
 619 int au_hnotify(struct inode *h_dir, struct au_hnotify *hnotify, u32 mask,
 620                struct qstr *h_child_qstr, struct inode *h_child_inode);
 621 int au_hnotify_reset_br(unsigned int udba, struct au_branch *br, int perm);
 622 int au_hnotify_init_br(struct au_branch *br, int perm);
 623 void au_hnotify_fin_br(struct au_branch *br);
 624 int __init au_hnotify_init(void);
 625 void au_hnotify_fin(void);
 626
 627 /* hfsnotify.c */
 628 extern const struct au_hnotify_op au_hnotify_op;
 629
 630 static inline
 631 void au_hn_init(struct au_hinode *hinode)
 632 {
 633         hinode->hi_notify = NULL;
 634 }
 635
 636 static inline struct au_hnotify *au_hn(struct au_hinode *hinode)
 637 {
 638         return hinode->hi_notify;
 639 }
 640
 641 #else
 642 AuStub(int, au_hn_alloc, return -EOPNOTSUPP,
 643        struct au_hinode *hinode __maybe_unused,
 644        struct inode *inode __maybe_unused)
 645 AuStub(struct au_hnotify *, au_hn, return NULL, struct au_hinode *hinode)
 646 AuStubVoid(au_hn_free, struct au_hinode *hinode __maybe_unused)
 647 AuStubVoid(au_hn_ctl, struct au_hinode *hinode __maybe_unused,
 648            int do_set __maybe_unused)
 649 AuStubVoid(au_hn_reset, struct inode *inode __maybe_unused,
 650            unsigned int flags __maybe_unused)
 651 AuStubInt0(au_hnotify_reset_br, unsigned int udba __maybe_unused,
 652            struct au_branch *br __maybe_unused,
 653            int perm __maybe_unused)
 654 AuStubInt0(au_hnotify_init_br, struct au_branch *br __maybe_unused,
 655            int perm __maybe_unused)
 656 AuStubVoid(au_hnotify_fin_br, struct au_branch *br __maybe_unused)
 657 AuStubInt0(__init au_hnotify_init, void)
 658 AuStubVoid(au_hnotify_fin, void)
 659 AuStubVoid(au_hn_init, struct au_hinode *hinode __maybe_unused)
 660 #endif /* CONFIG_AUFS_HNOTIFY */
 661
 662 static inline void au_hn_suspend(struct au_hinode *hdir)
 663 {
 664         au_hn_ctl(hdir, /*do_set*/0);
 665 }
 666
 667 static inline void au_hn_resume(struct au_hinode *hdir)
 668 {
 669         au_hn_ctl(hdir, /*do_set*/1);
 670 }
 671
 672 static inline void au_hn_inode_lock(struct au_hinode *hdir)
 673 {
 674         inode_lock(hdir->hi_inode);
 675         au_hn_suspend(hdir);
 676 }
 677
 678 static inline void au_hn_inode_lock_nested(struct au_hinode *hdir,
 679                                           unsigned int sc __maybe_unused)
 680 {
 681         inode_lock_nested(hdir->hi_inode, sc);
 682         au_hn_suspend(hdir);
 683 }
 684
 685 static inline void au_hn_inode_unlock(struct au_hinode *hdir)
 686 {
 687         au_hn_resume(hdir);
 688         inode_unlock(hdir->hi_inode);
 689 }
 690
 691 #endif /* __KERNEL__ */
 692 #endif /* __AUFS_INODE_H__ */