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1/* SPDX-License-Identifier: GPL-2.0+ */2/*3 * NILFS Segment buffer prototypes and definitions4 *5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.6 *7 * Written by Ryusuke Konishi.8 *9 */10#ifndef _NILFS_SEGBUF_H11#define _NILFS_SEGBUF_H12 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 summary20 * @flags: Flags21 * @nfinfo: Number of file information structures22 * @nblocks: Number of blocks included in the partial segment23 * @nsumblk: Number of summary blocks24 * @sumbytes: Byte count of segment summary25 * @nfileblk: Total number of file blocks26 * @seg_seq: Segment sequence number27 * @cno: Checkpoint number28 * @ctime: Creation time29 * @next: Block number of the next full segment30 */31struct 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 buffer46 * @sb_super: back pointer to a superblock struct47 * @sb_list: List head to chain this structure48 * @sb_sum: On-memory segment summary49 * @sb_segnum: Index number of the full segment50 * @sb_nextnum: Index number of the next full segment51 * @sb_fseg_start: Start block number of the full segment52 * @sb_fseg_end: End block number of the full segment53 * @sb_pseg_start: Disk block number of partial segment54 * @sb_rest_blocks: Number of residual blocks in the current segment55 * @sb_segsum_buffers: List of buffers for segment summaries56 * @sb_payload_buffers: List of buffers for segment payload57 * @sb_super_root: Pointer to buffer storing a super root block (if exists)58 * @sb_nbio: Number of flying bio requests59 * @sb_err: I/O error status60 * @sb_bio_event: Completion event of log writing61 */62struct 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 104extern struct kmem_cache *nilfs_segbuf_cachep;105 106struct nilfs_segment_buffer *nilfs_segbuf_new(struct super_block *);107void nilfs_segbuf_free(struct nilfs_segment_buffer *);108void nilfs_segbuf_map(struct nilfs_segment_buffer *, __u64, unsigned long,109 struct the_nilfs *);110void nilfs_segbuf_map_cont(struct nilfs_segment_buffer *segbuf,111 struct nilfs_segment_buffer *prev);112void nilfs_segbuf_set_next_segnum(struct nilfs_segment_buffer *, __u64,113 struct the_nilfs *);114int nilfs_segbuf_reset(struct nilfs_segment_buffer *, unsigned int, time64_t,115 __u64);116int nilfs_segbuf_extend_segsum(struct nilfs_segment_buffer *);117int nilfs_segbuf_extend_payload(struct nilfs_segment_buffer *,118 struct buffer_head **);119void nilfs_segbuf_fill_in_segsum(struct nilfs_segment_buffer *);120 121static 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 129static inline int nilfs_segbuf_empty(struct nilfs_segment_buffer *segbuf)130{131 return segbuf->sb_sum.nblocks == segbuf->sb_sum.nsumblk;132}133 134static inline void135nilfs_segbuf_add_segsum_buffer(struct nilfs_segment_buffer *segbuf,136 struct buffer_head *bh)137{138 list_add_tail(&bh->b_assoc_buffers, &segbuf->sb_segsum_buffers);139 segbuf->sb_sum.nblocks++;140 segbuf->sb_sum.nsumblk++;141}142 143static inline void144nilfs_segbuf_add_payload_buffer(struct nilfs_segment_buffer *segbuf,145 struct buffer_head *bh)146{147 list_add_tail(&bh->b_assoc_buffers, &segbuf->sb_payload_buffers);148 segbuf->sb_sum.nblocks++;149}150 151static inline void152nilfs_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 160void nilfs_clear_logs(struct list_head *logs);161void nilfs_truncate_logs(struct list_head *logs,162 struct nilfs_segment_buffer *last);163int nilfs_write_logs(struct list_head *logs, struct the_nilfs *nilfs);164int nilfs_wait_on_logs(struct list_head *logs);165void nilfs_add_checksums_on_logs(struct list_head *logs, u32 seed);166 167static inline void nilfs_destroy_logs(struct list_head *logs)168{169 nilfs_truncate_logs(logs, NULL);170}171 172#endif /* _NILFS_SEGBUF_H */173