fs/aufs/loop.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  * support for loopback mount as a branch
  20  */
  21
  22 #ifndef __AUFS_LOOP_H__
  23 #define __AUFS_LOOP_H__
  24
  25 #ifdef __KERNEL__
  26
  27 struct dentry;
  28 struct super_block;
  29
  30 #ifdef CONFIG_AUFS_BDEV_LOOP
  31 /* drivers/block/loop.c */
  32 struct file *loop_backing_file(struct super_block *sb);
  33
  34 /* loop.c */
  35 int au_test_loopback_overlap(struct super_block *sb, struct dentry *h_adding);
  36 int au_test_loopback_kthread(void);
  37 void au_warn_loopback(struct super_block *h_sb);
  38
  39 int au_loopback_init(void);
  40 void au_loopback_fin(void);
  41
  42 struct file *aufs_real_loop(struct file *file);
  43 #else
  44 AuStub(struct file *, loop_backing_file, return NULL)
  45
  46 AuStubInt0(au_test_loopback_overlap, struct super_block *sb,
  47            struct dentry *h_adding)
  48 AuStubInt0(au_test_loopback_kthread, void)
  49 AuStubVoid(au_warn_loopback, struct super_block *h_sb)
  50
  51 AuStubInt0(au_loopback_init, void)
  52 AuStubVoid(au_loopback_fin, void)
  53
  54 AuStub(struct file *, aufs_real_loop, return NULL, struct file *file)
  55 #endif /* BLK_DEV_LOOP */
  56
  57 #endif /* __KERNEL__ */
  58 #endif /* __AUFS_LOOP_H__ */