| /* SPDX-License-Identifier: GPL-2.0+ */ |
| /* |
| * segbuf.h - NILFS Segment buffer prototypes and definitions |
| * |
| * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. |
| * |
| * Written by Ryusuke Konishi. |
| * |
| */ |
| #ifndef _NILFS_SEGBUF_H |
| #define _NILFS_SEGBUF_H |
| |
| #include <linux/fs.h> |
| #include <linux/buffer_head.h> |
| #include <linux/bio.h> |
| #include <linux/completion.h> |
| |
| /** |
| * struct nilfs_segsum_info - On-memory segment summary |
| * @flags: Flags |
| * @nfinfo: Number of file information structures |
| * @nblocks: Number of blocks included in the partial segment |
| * @nsumblk: Number of summary blocks |
| * @sumbytes: Byte count of segment summary |
| * @nfileblk: Total number of file blocks |
| * @seg_seq: Segment sequence number |
| * @cno: Checkpoint number |
| * @ctime: Creation time |
| * @next: Block number of the next full segment |
| */ |
| struct nilfs_segsum_info { |
| unsigned int flags; |
| unsigned long nfinfo; |
| unsigned long nblocks; |
| unsigned long nsumblk; |
| unsigned long sumbytes; |
| unsigned long nfileblk; |
| u64 seg_seq; |
| __u64 cno; |
| time64_t ctime; |
| sector_t next; |
| }; |
| |
| /** |
| * struct nilfs_segment_buffer - Segment buffer |
| * @sb_super: back pointer to a superblock struct |
| * @sb_list: List head to chain this structure |
| * @sb_sum: On-memory segment summary |
| * @sb_segnum: Index number of the full segment |
| * @sb_nextnum: Index number of the next full segment |
| * @sb_fseg_start: Start block number of the full segment |
| * @sb_fseg_end: End block number of the full segment |
| * @sb_pseg_start: Disk block number of partial segment |
| * @sb_rest_blocks: Number of residual blocks in the current segment |
| * @sb_segsum_buffers: List of buffers for segment summaries |
| * @sb_payload_buffers: List of buffers for segment payload |
| * @sb_super_root: Pointer to buffer storing a super root block (if exists) |
| * @sb_nbio: Number of flying bio requests |
| * @sb_err: I/O error status |
| * @sb_bio_event: Completion event of log writing |
| */ |
| struct nilfs_segment_buffer { |
| struct super_block *sb_super; |
| struct list_head sb_list; |
| |
| /* Segment information */ |
| struct nilfs_segsum_info sb_sum; |
| __u64 sb_segnum; |
| __u64 sb_nextnum; |
| sector_t sb_fseg_start, sb_fseg_end; |
| sector_t sb_pseg_start; |
| unsigned int sb_rest_blocks; |
| |
| /* Buffers */ |
| struct list_head sb_segsum_buffers; |
| struct list_head sb_payload_buffers; /* including super root */ |
| struct buffer_head *sb_super_root; |
| |
| /* io status */ |
| int sb_nbio; |
| atomic_t sb_err; |
| struct completion sb_bio_event; |
| }; |
| |
| #define NILFS_LIST_SEGBUF(head) \ |
| list_entry((head), struct nilfs_segment_buffer, sb_list) |
| #define NILFS_NEXT_SEGBUF(segbuf) NILFS_LIST_SEGBUF((segbuf)->sb_list.next) |
| #define NILFS_PREV_SEGBUF(segbuf) NILFS_LIST_SEGBUF((segbuf)->sb_list.prev) |
| #define NILFS_LAST_SEGBUF(head) NILFS_LIST_SEGBUF((head)->prev) |
| #define NILFS_FIRST_SEGBUF(head) NILFS_LIST_SEGBUF((head)->next) |
| #define NILFS_SEGBUF_IS_LAST(segbuf, head) ((segbuf)->sb_list.next == (head)) |
| |
| #define nilfs_for_each_segbuf_before(s, t, h) \ |
| for ((s) = NILFS_FIRST_SEGBUF(h); (s) != (t); \ |
| (s) = NILFS_NEXT_SEGBUF(s)) |
| |
| #define NILFS_SEGBUF_FIRST_BH(head) \ |
| (list_entry((head)->next, struct buffer_head, b_assoc_buffers)) |
| #define NILFS_SEGBUF_NEXT_BH(bh) \ |
| (list_entry((bh)->b_assoc_buffers.next, struct buffer_head, \ |
| b_assoc_buffers)) |
| #define NILFS_SEGBUF_BH_IS_LAST(bh, head) ((bh)->b_assoc_buffers.next == head) |
| |
| extern struct kmem_cache *nilfs_segbuf_cachep; |
| |
| struct nilfs_segment_buffer *nilfs_segbuf_new(struct super_block *); |
| void nilfs_segbuf_free(struct nilfs_segment_buffer *); |
| void nilfs_segbuf_map(struct nilfs_segment_buffer *, __u64, unsigned long, |
| struct the_nilfs *); |
| void nilfs_segbuf_map_cont(struct nilfs_segment_buffer *segbuf, |
| struct nilfs_segment_buffer *prev); |
| void nilfs_segbuf_set_next_segnum(struct nilfs_segment_buffer *, __u64, |
| struct the_nilfs *); |
| int nilfs_segbuf_reset(struct nilfs_segment_buffer *, unsigned int, time64_t, |
| __u64); |
| int nilfs_segbuf_extend_segsum(struct nilfs_segment_buffer *); |
| int nilfs_segbuf_extend_payload(struct nilfs_segment_buffer *, |
| struct buffer_head **); |
| void nilfs_segbuf_fill_in_segsum(struct nilfs_segment_buffer *); |
| |
| static inline int nilfs_segbuf_simplex(struct nilfs_segment_buffer *segbuf) |
| { |
| unsigned int flags = segbuf->sb_sum.flags; |
| |
| return (flags & (NILFS_SS_LOGBGN | NILFS_SS_LOGEND)) == |
| (NILFS_SS_LOGBGN | NILFS_SS_LOGEND); |
| } |
| |
| static inline int nilfs_segbuf_empty(struct nilfs_segment_buffer *segbuf) |
| { |
| return segbuf->sb_sum.nblocks == segbuf->sb_sum.nsumblk; |
| } |
| |
| static inline void |
| nilfs_segbuf_add_segsum_buffer(struct nilfs_segment_buffer *segbuf, |
| struct buffer_head *bh) |
| { |
| list_add_tail(&bh->b_assoc_buffers, &segbuf->sb_segsum_buffers); |
| segbuf->sb_sum.nblocks++; |
| segbuf->sb_sum.nsumblk++; |
| } |
| |
| static inline void |
| nilfs_segbuf_add_payload_buffer(struct nilfs_segment_buffer *segbuf, |
| struct buffer_head *bh) |
| { |
| list_add_tail(&bh->b_assoc_buffers, &segbuf->sb_payload_buffers); |
| segbuf->sb_sum.nblocks++; |
| } |
| |
| static inline void |
| nilfs_segbuf_add_file_buffer(struct nilfs_segment_buffer *segbuf, |
| struct buffer_head *bh) |
| { |
| get_bh(bh); |
| nilfs_segbuf_add_payload_buffer(segbuf, bh); |
| segbuf->sb_sum.nfileblk++; |
| } |
| |
| void nilfs_clear_logs(struct list_head *logs); |
| void nilfs_truncate_logs(struct list_head *logs, |
| struct nilfs_segment_buffer *last); |
| int nilfs_write_logs(struct list_head *logs, struct the_nilfs *nilfs); |
| int nilfs_wait_on_logs(struct list_head *logs); |
| void nilfs_add_checksums_on_logs(struct list_head *logs, u32 seed); |
| |
| static inline void nilfs_destroy_logs(struct list_head *logs) |
| { |
| nilfs_truncate_logs(logs, NULL); |
| } |
| |
| #endif /* _NILFS_SEGBUF_H */ |