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 struct nilfs_shadow_map { 32 struct nilfs_bmap_store bmap_store; 33 struct address_space frozen_data; 34 struct address_space frozen_btnodes; 35 struct list_head frozen_buffers; 36 }; 37 38 /** 39 * struct nilfs_mdt_info - on-memory private data of meta data files 40 * @mi_nilfs: back pointer to the_nilfs struct 41 * @mi_sem: reader/writer semaphore for meta data operations 42 * @mi_bgl: per-blockgroup locking 43 * @mi_entry_size: size of an entry 44 * @mi_first_entry_offset: offset to the first entry 45 * @mi_entries_per_block: number of entries in a block 46 * @mi_palloc_cache: persistent object allocator cache 47 * @mi_shadow: shadow of bmap and page caches 48 * @mi_blocks_per_group: number of blocks in a group 49 * @mi_blocks_per_desc_block: number of blocks per descriptor block 50 */ 51 struct nilfs_mdt_info { 52 struct the_nilfs *mi_nilfs; 53 struct rw_semaphore mi_sem; 54 struct blockgroup_lock *mi_bgl; 55 unsigned mi_entry_size; 56 unsigned mi_first_entry_offset; 57 unsigned long mi_entries_per_block; 58 struct nilfs_palloc_cache *mi_palloc_cache; 59 struct nilfs_shadow_map *mi_shadow; 60 unsigned long mi_blocks_per_group; 61 unsigned long mi_blocks_per_desc_block; 62 }; 63 64 static inline struct nilfs_mdt_info *NILFS_MDT(const struct inode *inode) 65 { 66 return inode->i_private; 67 } 68 69 static inline struct the_nilfs *NILFS_I_NILFS(struct inode *inode) 70 { 71 struct super_block *sb = inode->i_sb; 72 73 return sb ? NILFS_SB(sb)->s_nilfs : NILFS_MDT(inode)->mi_nilfs; 74 } 75 76 /* Default GFP flags using highmem */ 77 #define NILFS_MDT_GFP (__GFP_WAIT | __GFP_IO | __GFP_HIGHMEM) 78 79 int nilfs_mdt_get_block(struct inode *, unsigned long, int, 80 void (*init_block)(struct inode *, 81 struct buffer_head *, void *), 82 struct buffer_head **); 83 int nilfs_mdt_delete_block(struct inode *, unsigned long); 84 int nilfs_mdt_forget_block(struct inode *, unsigned long); 85 int nilfs_mdt_mark_block_dirty(struct inode *, unsigned long); 86 int nilfs_mdt_fetch_dirty(struct inode *); 87 88 int nilfs_mdt_init(struct inode *inode, struct the_nilfs *nilfs, 89 gfp_t gfp_mask, size_t objsz); 90 struct inode *nilfs_mdt_new(struct the_nilfs *, struct super_block *, ino_t, 91 size_t); 92 struct inode *nilfs_mdt_new_common(struct the_nilfs *, struct super_block *, 93 ino_t); 94 void nilfs_mdt_destroy(struct inode *); 95 void nilfs_mdt_set_entry_size(struct inode *, unsigned, unsigned); 96 void nilfs_mdt_set_shadow(struct inode *, struct inode *); 97 98 int nilfs_mdt_setup_shadow_map(struct inode *inode, 99 struct nilfs_shadow_map *shadow); 100 int nilfs_mdt_save_to_shadow_map(struct inode *inode); 101 void nilfs_mdt_restore_from_shadow_map(struct inode *inode); 102 void nilfs_mdt_clear_shadow_map(struct inode *inode); 103 int nilfs_mdt_freeze_buffer(struct inode *inode, struct buffer_head *bh); 104 struct buffer_head *nilfs_mdt_get_frozen_buffer(struct inode *inode, 105 struct buffer_head *bh); 106 107 #define nilfs_mdt_mark_buffer_dirty(bh) nilfs_mark_buffer_dirty(bh) 108 109 static inline void nilfs_mdt_mark_dirty(struct inode *inode) 110 { 111 if (!test_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state)) 112 set_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state); 113 } 114 115 static inline void nilfs_mdt_clear_dirty(struct inode *inode) 116 { 117 clear_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state); 118 } 119 120 static inline __u64 nilfs_mdt_cno(struct inode *inode) 121 { 122 return NILFS_MDT(inode)->mi_nilfs->ns_cno; 123 } 124 125 #define nilfs_mdt_bgl_lock(inode, bg) \ 126 (&NILFS_MDT(inode)->mi_bgl->locks[(bg) & (NR_BG_LOCKS-1)].lock) 127 128 #endif /* _NILFS_MDT_H */ 129