1 | /* SPDX-License-Identifier: GPL-2.0+ */ |
2 | /* |
3 | * NILFS Segment buffer prototypes and definitions |
4 | * |
5 | * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. |
6 | * |
7 | * Written by Ryusuke Konishi. |
8 | * |
9 | */ |
10 | #ifndef _NILFS_SEGBUF_H |
11 | #define _NILFS_SEGBUF_H |
12 | |
13 | #include <linux/fs.h> |
14 | #include <linux/buffer_head.h> |
15 | #include <linux/bio.h> |
16 | #include <linux/completion.h> |
17 | |
18 | /** |
19 | * struct nilfs_segsum_info - On-memory segment summary |
20 | * @flags: Flags |
21 | * @nfinfo: Number of file information structures |
22 | * @nblocks: Number of blocks included in the partial segment |
23 | * @nsumblk: Number of summary blocks |
24 | * @sumbytes: Byte count of segment summary |
25 | * @nfileblk: Total number of file blocks |
26 | * @seg_seq: Segment sequence number |
27 | * @cno: Checkpoint number |
28 | * @ctime: Creation time |
29 | * @next: Block number of the next full segment |
30 | */ |
31 | struct nilfs_segsum_info { |
32 | unsigned int flags; |
33 | unsigned long nfinfo; |
34 | unsigned long nblocks; |
35 | unsigned long nsumblk; |
36 | unsigned long sumbytes; |
37 | unsigned long nfileblk; |
38 | u64 seg_seq; |
39 | __u64 cno; |
40 | time64_t ctime; |
41 | sector_t next; |
42 | }; |
43 | |
44 | /** |
45 | * struct nilfs_segment_buffer - Segment buffer |
46 | * @sb_super: back pointer to a superblock struct |
47 | * @sb_list: List head to chain this structure |
48 | * @sb_sum: On-memory segment summary |
49 | * @sb_segnum: Index number of the full segment |
50 | * @sb_nextnum: Index number of the next full segment |
51 | * @sb_fseg_start: Start block number of the full segment |
52 | * @sb_fseg_end: End block number of the full segment |
53 | * @sb_pseg_start: Disk block number of partial segment |
54 | * @sb_rest_blocks: Number of residual blocks in the current segment |
55 | * @sb_segsum_buffers: List of buffers for segment summaries |
56 | * @sb_payload_buffers: List of buffers for segment payload |
57 | * @sb_super_root: Pointer to buffer storing a super root block (if exists) |
58 | * @sb_nbio: Number of flying bio requests |
59 | * @sb_err: I/O error status |
60 | * @sb_bio_event: Completion event of log writing |
61 | */ |
62 | struct nilfs_segment_buffer { |
63 | struct super_block *sb_super; |
64 | struct list_head sb_list; |
65 | |
66 | /* Segment information */ |
67 | struct nilfs_segsum_info sb_sum; |
68 | __u64 sb_segnum; |
69 | __u64 sb_nextnum; |
70 | sector_t sb_fseg_start, sb_fseg_end; |
71 | sector_t sb_pseg_start; |
72 | unsigned int sb_rest_blocks; |
73 | |
74 | /* Buffers */ |
75 | struct list_head sb_segsum_buffers; |
76 | struct list_head sb_payload_buffers; /* including super root */ |
77 | struct buffer_head *sb_super_root; |
78 | |
79 | /* io status */ |
80 | int sb_nbio; |
81 | atomic_t sb_err; |
82 | struct completion sb_bio_event; |
83 | }; |
84 | |
85 | #define NILFS_LIST_SEGBUF(head) \ |
86 | list_entry((head), struct nilfs_segment_buffer, sb_list) |
87 | #define NILFS_NEXT_SEGBUF(segbuf) NILFS_LIST_SEGBUF((segbuf)->sb_list.next) |
88 | #define NILFS_PREV_SEGBUF(segbuf) NILFS_LIST_SEGBUF((segbuf)->sb_list.prev) |
89 | #define NILFS_LAST_SEGBUF(head) NILFS_LIST_SEGBUF((head)->prev) |
90 | #define NILFS_FIRST_SEGBUF(head) NILFS_LIST_SEGBUF((head)->next) |
91 | #define NILFS_SEGBUF_IS_LAST(segbuf, head) ((segbuf)->sb_list.next == (head)) |
92 | |
93 | #define nilfs_for_each_segbuf_before(s, t, h) \ |
94 | for ((s) = NILFS_FIRST_SEGBUF(h); (s) != (t); \ |
95 | (s) = NILFS_NEXT_SEGBUF(s)) |
96 | |
97 | #define NILFS_SEGBUF_FIRST_BH(head) \ |
98 | (list_entry((head)->next, struct buffer_head, b_assoc_buffers)) |
99 | #define NILFS_SEGBUF_NEXT_BH(bh) \ |
100 | (list_entry((bh)->b_assoc_buffers.next, struct buffer_head, \ |
101 | b_assoc_buffers)) |
102 | #define NILFS_SEGBUF_BH_IS_LAST(bh, head) ((bh)->b_assoc_buffers.next == head) |
103 | |
104 | extern struct kmem_cache *nilfs_segbuf_cachep; |
105 | |
106 | struct nilfs_segment_buffer *nilfs_segbuf_new(struct super_block *); |
107 | void nilfs_segbuf_free(struct nilfs_segment_buffer *); |
108 | void nilfs_segbuf_map(struct nilfs_segment_buffer *, __u64, unsigned long, |
109 | struct the_nilfs *); |
110 | void nilfs_segbuf_map_cont(struct nilfs_segment_buffer *segbuf, |
111 | struct nilfs_segment_buffer *prev); |
112 | void nilfs_segbuf_set_next_segnum(struct nilfs_segment_buffer *, __u64, |
113 | struct the_nilfs *); |
114 | int nilfs_segbuf_reset(struct nilfs_segment_buffer *, unsigned int, time64_t, |
115 | __u64); |
116 | int nilfs_segbuf_extend_segsum(struct nilfs_segment_buffer *); |
117 | int nilfs_segbuf_extend_payload(struct nilfs_segment_buffer *, |
118 | struct buffer_head **); |
119 | void nilfs_segbuf_fill_in_segsum(struct nilfs_segment_buffer *); |
120 | |
121 | static inline int nilfs_segbuf_simplex(struct nilfs_segment_buffer *segbuf) |
122 | { |
123 | unsigned int flags = segbuf->sb_sum.flags; |
124 | |
125 | return (flags & (NILFS_SS_LOGBGN | NILFS_SS_LOGEND)) == |
126 | (NILFS_SS_LOGBGN | NILFS_SS_LOGEND); |
127 | } |
128 | |
129 | static inline int nilfs_segbuf_empty(struct nilfs_segment_buffer *segbuf) |
130 | { |
131 | return segbuf->sb_sum.nblocks == segbuf->sb_sum.nsumblk; |
132 | } |
133 | |
134 | static inline void |
135 | nilfs_segbuf_add_segsum_buffer(struct nilfs_segment_buffer *segbuf, |
136 | struct buffer_head *bh) |
137 | { |
138 | list_add_tail(new: &bh->b_assoc_buffers, head: &segbuf->sb_segsum_buffers); |
139 | segbuf->sb_sum.nblocks++; |
140 | segbuf->sb_sum.nsumblk++; |
141 | } |
142 | |
143 | static inline void |
144 | nilfs_segbuf_add_payload_buffer(struct nilfs_segment_buffer *segbuf, |
145 | struct buffer_head *bh) |
146 | { |
147 | list_add_tail(new: &bh->b_assoc_buffers, head: &segbuf->sb_payload_buffers); |
148 | segbuf->sb_sum.nblocks++; |
149 | } |
150 | |
151 | static inline void |
152 | nilfs_segbuf_add_file_buffer(struct nilfs_segment_buffer *segbuf, |
153 | struct buffer_head *bh) |
154 | { |
155 | get_bh(bh); |
156 | nilfs_segbuf_add_payload_buffer(segbuf, bh); |
157 | segbuf->sb_sum.nfileblk++; |
158 | } |
159 | |
160 | void nilfs_clear_logs(struct list_head *logs); |
161 | void nilfs_truncate_logs(struct list_head *logs, |
162 | struct nilfs_segment_buffer *last); |
163 | int nilfs_write_logs(struct list_head *logs, struct the_nilfs *nilfs); |
164 | int nilfs_wait_on_logs(struct list_head *logs); |
165 | void nilfs_add_checksums_on_logs(struct list_head *logs, u32 seed); |
166 | |
167 | static inline void nilfs_destroy_logs(struct list_head *logs) |
168 | { |
169 | nilfs_truncate_logs(logs, NULL); |
170 | } |
171 | |
172 | #endif /* _NILFS_SEGBUF_H */ |
173 | |