fs/aufs/whout.h

   1 /*
   2  * Copyright (C) 2005-2017 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  * whiteout for logical deletion and opaque directory
  20  */
  21
  22 #ifndef __AUFS_WHOUT_H__
  23 #define __AUFS_WHOUT_H__
  24
  25 #ifdef __KERNEL__
  26
  27 #include "dir.h"
  28
  29 /* whout.c */
  30 int au_wh_name_alloc(struct qstr *wh, const struct qstr *name);
  31 int au_wh_test(struct dentry *h_parent, struct qstr *wh_name, int try_sio);
  32 int au_diropq_test(struct dentry *h_dentry);
  33 struct au_branch;
  34 struct dentry *au_whtmp_lkup(struct dentry *h_parent, struct au_branch *br,
  35                              struct qstr *prefix);
  36 int au_whtmp_ren(struct dentry *h_dentry, struct au_branch *br);
  37 int au_wh_unlink_dentry(struct inode *h_dir, struct path *h_path,
  38                         struct dentry *dentry);
  39 int au_wh_init(struct au_branch *br, struct super_block *sb);
  40
  41 /* diropq flags */
  42 #define AuDiropq_CREATE 1
  43 #define au_ftest_diropq(flags, name)    ((flags) & AuDiropq_##name)
  44 #define au_fset_diropq(flags, name) \
  45         do { (flags) |= AuDiropq_##name; } while (0)
  46 #define au_fclr_diropq(flags, name) \
  47         do { (flags) &= ~AuDiropq_##name; } while (0)
  48
  49 struct dentry *au_diropq_sio(struct dentry *dentry, aufs_bindex_t bindex,
  50                              unsigned int flags);
  51 struct dentry *au_wh_lkup(struct dentry *h_parent, struct qstr *base_name,
  52                           struct au_branch *br);
  53 struct dentry *au_wh_create(struct dentry *dentry, aufs_bindex_t bindex,
  54                             struct dentry *h_parent);
  55
  56 /* real rmdir for the whiteout-ed dir */
  57 struct au_whtmp_rmdir {
  58         struct inode *dir;
  59         struct au_branch *br;
  60         struct dentry *wh_dentry;
  61         struct au_nhash whlist;
  62 };
  63
  64 struct au_whtmp_rmdir *au_whtmp_rmdir_alloc(struct super_block *sb, gfp_t gfp);
  65 void au_whtmp_rmdir_free(struct au_whtmp_rmdir *whtmp);
  66 int au_whtmp_rmdir(struct inode *dir, aufs_bindex_t bindex,
  67                    struct dentry *wh_dentry, struct au_nhash *whlist);
  68 void au_whtmp_kick_rmdir(struct inode *dir, aufs_bindex_t bindex,
  69                          struct dentry *wh_dentry, struct au_whtmp_rmdir *args);
  70
  71 /* ---------------------------------------------------------------------- */
  72
  73 static inline struct dentry *au_diropq_create(struct dentry *dentry,
  74                                               aufs_bindex_t bindex)
  75 {
  76         return au_diropq_sio(dentry, bindex, AuDiropq_CREATE);
  77 }
  78
  79 static inline int au_diropq_remove(struct dentry *dentry, aufs_bindex_t bindex)
  80 {
  81         return PTR_ERR(au_diropq_sio(dentry, bindex, !AuDiropq_CREATE));
  82 }
  83
  84 #endif /* __KERNEL__ */
  85 #endif /* __AUFS_WHOUT_H__ */