xref: /openbmc/linux/fs/nilfs2/mdt.h (revision d9fd5a71)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * mdt.h - NILFS meta data file prototype and definitions
4  *
5  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6  *
7  * Written by Ryusuke Konishi.
8  */
9 
10 #ifndef _NILFS_MDT_H
11 #define _NILFS_MDT_H
12 
13 #include <linux/buffer_head.h>
14 #include <linux/blockgroup_lock.h>
15 #include "nilfs.h"
16 #include "page.h"
17 
18 /**
19  * struct nilfs_shadow_map - shadow mapping of meta data file
20  * @bmap_store: shadow copy of bmap state
21  * @frozen_data: shadowed dirty data pages
22  * @frozen_btnodes: shadowed dirty b-tree nodes' pages
23  * @frozen_buffers: list of frozen buffers
24  */
25 struct nilfs_shadow_map {
26 	struct nilfs_bmap_store bmap_store;
27 	struct address_space frozen_data;
28 	struct address_space frozen_btnodes;
29 	struct list_head frozen_buffers;
30 };
31 
32 /**
33  * struct nilfs_mdt_info - on-memory private data of meta data files
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_palloc_cache: persistent object allocator cache
40  * @mi_shadow: shadow of bmap and page caches
41  * @mi_blocks_per_group: number of blocks in a group
42  * @mi_blocks_per_desc_block: number of blocks per descriptor block
43  */
44 struct nilfs_mdt_info {
45 	struct rw_semaphore	mi_sem;
46 	struct blockgroup_lock *mi_bgl;
47 	unsigned int		mi_entry_size;
48 	unsigned int		mi_first_entry_offset;
49 	unsigned long		mi_entries_per_block;
50 	struct nilfs_palloc_cache *mi_palloc_cache;
51 	struct nilfs_shadow_map *mi_shadow;
52 	unsigned long		mi_blocks_per_group;
53 	unsigned long		mi_blocks_per_desc_block;
54 };
55 
56 static inline struct nilfs_mdt_info *NILFS_MDT(const struct inode *inode)
57 {
58 	return inode->i_private;
59 }
60 
61 static inline int nilfs_is_metadata_file_inode(const struct inode *inode)
62 {
63 	return inode->i_private != NULL;
64 }
65 
66 /* Default GFP flags using highmem */
67 #define NILFS_MDT_GFP      (__GFP_RECLAIM | __GFP_IO | __GFP_HIGHMEM)
68 
69 int nilfs_mdt_get_block(struct inode *, unsigned long, int,
70 			void (*init_block)(struct inode *,
71 					   struct buffer_head *, void *),
72 			struct buffer_head **);
73 int nilfs_mdt_find_block(struct inode *inode, unsigned long start,
74 			 unsigned long end, unsigned long *blkoff,
75 			 struct buffer_head **out_bh);
76 int nilfs_mdt_delete_block(struct inode *, unsigned long);
77 int nilfs_mdt_forget_block(struct inode *, unsigned long);
78 int nilfs_mdt_fetch_dirty(struct inode *);
79 
80 int nilfs_mdt_init(struct inode *inode, gfp_t gfp_mask, size_t objsz);
81 void nilfs_mdt_clear(struct inode *inode);
82 void nilfs_mdt_destroy(struct inode *inode);
83 
84 void nilfs_mdt_set_entry_size(struct inode *, unsigned int, unsigned int);
85 
86 int nilfs_mdt_setup_shadow_map(struct inode *inode,
87 			       struct nilfs_shadow_map *shadow);
88 int nilfs_mdt_save_to_shadow_map(struct inode *inode);
89 void nilfs_mdt_restore_from_shadow_map(struct inode *inode);
90 void nilfs_mdt_clear_shadow_map(struct inode *inode);
91 int nilfs_mdt_freeze_buffer(struct inode *inode, struct buffer_head *bh);
92 struct buffer_head *nilfs_mdt_get_frozen_buffer(struct inode *inode,
93 						struct buffer_head *bh);
94 
95 static inline void nilfs_mdt_mark_dirty(struct inode *inode)
96 {
97 	if (!test_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state))
98 		set_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state);
99 }
100 
101 static inline void nilfs_mdt_clear_dirty(struct inode *inode)
102 {
103 	clear_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state);
104 }
105 
106 static inline __u64 nilfs_mdt_cno(struct inode *inode)
107 {
108 	return ((struct the_nilfs *)inode->i_sb->s_fs_info)->ns_cno;
109 }
110 
111 static inline spinlock_t *
112 nilfs_mdt_bgl_lock(struct inode *inode, unsigned int block_group)
113 {
114 	return bgl_lock_ptr(NILFS_MDT(inode)->mi_bgl, block_group);
115 }
116 
117 #endif /* _NILFS_MDT_H */
118