fs/nilfs2/sb.h

   1 /*
   2  * sb.h - NILFS on-memory super block structure.
   3  *
   4  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  *
  20  * Written by Ryusuke Konishi <ryusuke@osrg.net>
  21  *
  22  */
  23
  24 #ifndef _NILFS_SB
  25 #define _NILFS_SB
  26
  27 #include <linux/types.h>
  28 #include <linux/fs.h>
  29
  30 /*
  31  * Mount options
  32  */
  33 struct nilfs_mount_options {
  34         unsigned long mount_opt;
  35         __u64 snapshot_cno;
  36 };
  37
  38 struct the_nilfs;
  39 struct nilfs_sc_info;
  40
  41 /*
  42  * NILFS super-block data in memory
  43  */
  44 struct nilfs_sb_info {
  45         /* Snapshot status */
  46         __u64 s_snapshot_cno;           /* Checkpoint number */
  47         atomic_t s_inodes_count;
  48         atomic_t s_blocks_count;        /* Reserved (might be deleted) */
  49
  50         /* Mount options */
  51         unsigned long s_mount_opt;
  52         uid_t s_resuid;
  53         gid_t s_resgid;
  54
  55         unsigned long s_interval;       /* construction interval */
  56         unsigned long s_watermark;      /* threshold of data amount
  57                                            for the segment construction */
  58
  59         /* Fundamental members */
  60         struct super_block *s_super;    /* reverse pointer to super_block */
  61         struct the_nilfs *s_nilfs;
  62         struct list_head s_list;        /* list head for nilfs->ns_supers */
  63         atomic_t s_count;               /* reference count */
  64
  65         /* Segment constructor */
  66         struct list_head s_dirty_files; /* dirty files list */
  67         struct nilfs_sc_info *s_sc_info; /* segment constructor info */
  68         spinlock_t s_inode_lock;        /* Lock for the nilfs inode.
  69                                            It covers s_dirty_files list */
  70
  71         /* Metadata files */
  72         struct inode *s_ifile;          /* index file inode */
  73
  74         /* Inode allocator */
  75         spinlock_t s_next_gen_lock;
  76         u32 s_next_generation;
  77 };
  78
  79 static inline struct nilfs_sb_info *NILFS_SB(struct super_block *sb)
  80 {
  81         return sb->s_fs_info;
  82 }
  83
  84 static inline struct nilfs_sc_info *NILFS_SC(struct nilfs_sb_info *sbi)
  85 {
  86         return sbi->s_sc_info;
  87 }
  88
  89 /*
  90  * Bit operations for the mount option
  91  */
  92 #define nilfs_clear_opt(sbi, opt)  \
  93         do { (sbi)->s_mount_opt &= ~NILFS_MOUNT_##opt; } while (0)
  94 #define nilfs_set_opt(sbi, opt)  \
  95         do { (sbi)->s_mount_opt |= NILFS_MOUNT_##opt; } while (0)
  96 #define nilfs_test_opt(sbi, opt)   ((sbi)->s_mount_opt & NILFS_MOUNT_##opt)
  97 #define nilfs_write_opt(sbi, mask, opt)                                 \
  98         do { (sbi)->s_mount_opt =                                       \
  99                 (((sbi)->s_mount_opt & ~NILFS_MOUNT_##mask) |           \
 100                  NILFS_MOUNT_##opt);                                    \
 101         } while (0)
 102
 103 #endif /* _NILFS_SB */