1 /* 2 * mdt.h - NILFS meta data file prototype and definitions 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 #ifndef _NILFS_MDT_H 24 #define _NILFS_MDT_H 25 26 #include <linux/buffer_head.h> 27 #include <linux/blockgroup_lock.h> 28 #include "nilfs.h" 29 #include "page.h" 30 31 /** 32 * struct nilfs_mdt_info - on-memory private data of meta data files 33 * @mi_nilfs: back pointer to the_nilfs struct 34 * @mi_sem: reader/writer semaphore for meta data operations 35 * @mi_bgl: per-blockgroup locking 36 * @mi_entry_size: size of an entry 37 * @mi_first_entry_offset: offset to the first entry 38 * @mi_entries_per_block: number of entries in a block 39 * @mi_blocks_per_group: number of blocks in a group 40 * @mi_blocks_per_desc_block: number of blocks per descriptor block 41 */ 42 struct nilfs_mdt_info { 43 struct the_nilfs *mi_nilfs; 44 struct rw_semaphore mi_sem; 45 struct blockgroup_lock *mi_bgl; 46 unsigned mi_entry_size; 47 unsigned mi_first_entry_offset; 48 unsigned long mi_entries_per_block; 49 unsigned long mi_blocks_per_group; 50 unsigned long mi_blocks_per_desc_block; 51 }; 52 53 static inline struct nilfs_mdt_info *NILFS_MDT(const struct inode *inode) 54 { 55 return inode->i_private; 56 } 57 58 static inline struct the_nilfs *NILFS_I_NILFS(struct inode *inode) 59 { 60 struct super_block *sb = inode->i_sb; 61 62 return sb ? NILFS_SB(sb)->s_nilfs : NILFS_MDT(inode)->mi_nilfs; 63 } 64 65 /* Default GFP flags using highmem */ 66 #define NILFS_MDT_GFP (__GFP_WAIT | __GFP_IO | __GFP_HIGHMEM) 67 68 int nilfs_mdt_get_block(struct inode *, unsigned long, int, 69 void (*init_block)(struct inode *, 70 struct buffer_head *, void *), 71 struct buffer_head **); 72 int nilfs_mdt_delete_block(struct inode *, unsigned long); 73 int nilfs_mdt_forget_block(struct inode *, unsigned long); 74 int nilfs_mdt_mark_block_dirty(struct inode *, unsigned long); 75 int nilfs_mdt_fetch_dirty(struct inode *); 76 77 struct inode *nilfs_mdt_new(struct the_nilfs *, struct super_block *, ino_t, 78 size_t); 79 struct inode *nilfs_mdt_new_common(struct the_nilfs *, struct super_block *, 80 ino_t, gfp_t, size_t); 81 void nilfs_mdt_destroy(struct inode *); 82 void nilfs_mdt_set_entry_size(struct inode *, unsigned, unsigned); 83 void nilfs_mdt_set_shadow(struct inode *, struct inode *); 84 85 86 #define nilfs_mdt_mark_buffer_dirty(bh) nilfs_mark_buffer_dirty(bh) 87 88 static inline void nilfs_mdt_mark_dirty(struct inode *inode) 89 { 90 if (!test_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state)) 91 set_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state); 92 } 93 94 static inline void nilfs_mdt_clear_dirty(struct inode *inode) 95 { 96 clear_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state); 97 } 98 99 static inline __u64 nilfs_mdt_cno(struct inode *inode) 100 { 101 return NILFS_MDT(inode)->mi_nilfs->ns_cno; 102 } 103 104 #define nilfs_mdt_bgl_lock(inode, bg) \ 105 (&NILFS_MDT(inode)->mi_bgl->locks[(bg) & (NR_BG_LOCKS-1)].lock) 106 107 #endif /* _NILFS_MDT_H */ 108