LXR linux/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 */
  33struct nilfs_mount_options {
  34        unsigned long mount_opt;
  35        __u64 snapshot_cno;
  36};
  37
  38struct the_nilfs;
  39struct nilfs_sc_info;
  40
  41/*
  42 * NILFS super-block data in memory
  43 */
  44struct 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
  64        /* Segment constructor */
  65        struct list_head s_dirty_files; /* dirty files list */
  66        struct nilfs_sc_info *s_sc_info; /* segment constructor info */
  67        spinlock_t s_inode_lock;        /* Lock for the nilfs inode.
  68                                           It covers s_dirty_files list */
  69
  70        /* Metadata files */
  71        struct inode *s_ifile;          /* index file inode */
  72
  73        /* Inode allocator */
  74        spinlock_t s_next_gen_lock;
  75        u32 s_next_generation;
  76};
  77
  78static inline struct nilfs_sb_info *NILFS_SB(struct super_block *sb)
  79{
  80        return sb->s_fs_info;
  81}
  82
  83static inline struct nilfs_sc_info *NILFS_SC(struct nilfs_sb_info *sbi)
  84{
  85        return sbi->s_sc_info;
  86}
  87
  88/*
  89 * Bit operations for the mount option
  90 */
  91#define nilfs_clear_opt(sbi, opt)  \
  92        do { (sbi)->s_mount_opt &= ~NILFS_MOUNT_##opt; } while (0)
  93#define nilfs_set_opt(sbi, opt)  \
  94        do { (sbi)->s_mount_opt |= NILFS_MOUNT_##opt; } while (0)
  95#define nilfs_test_opt(sbi, opt)   ((sbi)->s_mount_opt & NILFS_MOUNT_##opt)
  96#define nilfs_write_opt(sbi, mask, opt)                                 \
  97        do { (sbi)->s_mount_opt =                                       \
  98                (((sbi)->s_mount_opt & ~NILFS_MOUNT_##mask) |           \
  99                 NILFS_MOUNT_##opt);                                    \
 100        } while (0)
 101
 102#endif /* _NILFS_SB */
 103