fs/aufs/dir.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  * directory operations
  20  */
  21
  22 #ifndef __AUFS_DIR_H__
  23 #define __AUFS_DIR_H__
  24
  25 #ifdef __KERNEL__
  26
  27 #include <linux/fs.h>
  28
  29 /* ---------------------------------------------------------------------- */
  30
  31 /* need to be faster and smaller */
  32
  33 struct au_nhash {
  34         unsigned int            nh_num;
  35         struct hlist_head       *nh_head;
  36 };
  37
  38 struct au_vdir_destr {
  39         unsigned char   len;
  40         unsigned char   name[0];
  41 } __packed;
  42
  43 struct au_vdir_dehstr {
  44         struct hlist_node       hash;
  45         union {
  46                 struct au_vdir_destr    *str;
  47                 struct llist_node       lnode;  /* delayed free */
  48         };
  49 } ____cacheline_aligned_in_smp;
  50
  51 struct au_vdir_de {
  52         ino_t                   de_ino;
  53         unsigned char           de_type;
  54         /* caution: packed */
  55         struct au_vdir_destr    de_str;
  56 } __packed;
  57
  58 struct au_vdir_wh {
  59         struct hlist_node       wh_hash;
  60 #ifdef CONFIG_AUFS_SHWH
  61         ino_t                   wh_ino;
  62         aufs_bindex_t           wh_bindex;
  63         unsigned char           wh_type;
  64 #else
  65         aufs_bindex_t           wh_bindex;
  66 #endif
  67         /* caution: packed */
  68         struct au_vdir_destr    wh_str;
  69 } __packed;
  70
  71 union au_vdir_deblk_p {
  72         unsigned char           *deblk;
  73         struct au_vdir_de       *de;
  74 };
  75
  76 struct au_vdir {
  77         unsigned char   **vd_deblk;
  78         unsigned long   vd_nblk;
  79         struct {
  80                 unsigned long           ul;
  81                 union au_vdir_deblk_p   p;
  82         } vd_last;
  83
  84         unsigned long   vd_version;
  85         unsigned int    vd_deblk_sz;
  86         union {
  87                 unsigned long           vd_jiffy;
  88                 struct llist_node       vd_lnode;       /* delayed free */
  89         };
  90 } ____cacheline_aligned_in_smp;
  91
  92 /* ---------------------------------------------------------------------- */
  93
  94 /* dir.c */
  95 extern const struct file_operations aufs_dir_fop;
  96 void au_add_nlink(struct inode *dir, struct inode *h_dir);
  97 void au_sub_nlink(struct inode *dir, struct inode *h_dir);
  98 loff_t au_dir_size(struct file *file, struct dentry *dentry);
  99 void au_dir_ts(struct inode *dir, aufs_bindex_t bsrc);
 100 int au_test_empty_lower(struct dentry *dentry);
 101 int au_test_empty(struct dentry *dentry, struct au_nhash *whlist);
 102
 103 /* vdir.c */
 104 unsigned int au_rdhash_est(loff_t sz);
 105 int au_nhash_alloc(struct au_nhash *nhash, unsigned int num_hash, gfp_t gfp);
 106 void au_nhash_wh_free(struct au_nhash *whlist);
 107 int au_nhash_test_longer_wh(struct au_nhash *whlist, aufs_bindex_t btgt,
 108                             int limit);
 109 int au_nhash_test_known_wh(struct au_nhash *whlist, char *name, int nlen);
 110 int au_nhash_append_wh(struct au_nhash *whlist, char *name, int nlen, ino_t ino,
 111                        unsigned int d_type, aufs_bindex_t bindex,
 112                        unsigned char shwh);
 113 void au_vdir_free(struct au_vdir *vdir, int atonce);
 114 int au_vdir_init(struct file *file);
 115 int au_vdir_fill_de(struct file *file, struct dir_context *ctx);
 116
 117 /* ioctl.c */
 118 long aufs_ioctl_dir(struct file *file, unsigned int cmd, unsigned long arg);
 119
 120 #ifdef CONFIG_AUFS_RDU
 121 /* rdu.c */
 122 long au_rdu_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 123 #ifdef CONFIG_COMPAT
 124 long au_rdu_compat_ioctl(struct file *file, unsigned int cmd,
 125                          unsigned long arg);
 126 #endif
 127 #else
 128 AuStub(long, au_rdu_ioctl, return -EINVAL, struct file *file,
 129        unsigned int cmd, unsigned long arg)
 130 #ifdef CONFIG_COMPAT
 131 AuStub(long, au_rdu_compat_ioctl, return -EINVAL, struct file *file,
 132        unsigned int cmd, unsigned long arg)
 133 #endif
 134 #endif
 135
 136 #endif /* __KERNEL__ */
 137 #endif /* __AUFS_DIR_H__ */