linux/fs/nilfs2/segbuf.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * NILFS segment buffer
 *
 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
 *
 * Written by Ryusuke Konishi.
 *
 */

#include <linux/buffer_head.h>
#include <linux/writeback.h>
#include <linux/crc32.h>
#include <linux/backing-dev.h>
#include <linux/slab.h>
#include "page.h"
#include "segbuf.h"


struct nilfs_write_info { … };

static int nilfs_segbuf_write(struct nilfs_segment_buffer *segbuf,
			      struct the_nilfs *nilfs);
static int nilfs_segbuf_wait(struct nilfs_segment_buffer *segbuf);

struct nilfs_segment_buffer *nilfs_segbuf_new(struct super_block *sb)
{ … }

void nilfs_segbuf_free(struct nilfs_segment_buffer *segbuf)
{ … }

void nilfs_segbuf_map(struct nilfs_segment_buffer *segbuf, __u64 segnum,
		     unsigned long offset, struct the_nilfs *nilfs)
{ … }

/**
 * nilfs_segbuf_map_cont - map a new log behind a given log
 * @segbuf: new segment buffer
 * @prev: segment buffer containing a log to be continued
 */
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 *segbuf,
				  __u64 nextnum, struct the_nilfs *nilfs)
{ … }

int nilfs_segbuf_extend_segsum(struct nilfs_segment_buffer *segbuf)
{ … }

int nilfs_segbuf_extend_payload(struct nilfs_segment_buffer *segbuf,
				struct buffer_head **bhp)
{ … }

int nilfs_segbuf_reset(struct nilfs_segment_buffer *segbuf, unsigned int flags,
		       time64_t ctime, __u64 cno)
{ … }

/*
 * Setup segment summary
 */
void nilfs_segbuf_fill_in_segsum(struct nilfs_segment_buffer *segbuf)
{ … }

/*
 * CRC calculation routines
 */
static void
nilfs_segbuf_fill_in_segsum_crc(struct nilfs_segment_buffer *segbuf, u32 seed)
{ … }

static void nilfs_segbuf_fill_in_data_crc(struct nilfs_segment_buffer *segbuf,
					  u32 seed)
{ … }

static void
nilfs_segbuf_fill_in_super_root_crc(struct nilfs_segment_buffer *segbuf,
				    u32 seed)
{ … }

static void nilfs_release_buffers(struct list_head *list)
{ … }

static void nilfs_segbuf_clear(struct nilfs_segment_buffer *segbuf)
{ … }

/*
 * Iterators for segment buffers
 */
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)
{ … }

/**
 * nilfs_add_checksums_on_logs - add checksums on the logs
 * @logs: list of segment buffers storing target logs
 * @seed: checksum seed value
 */
void nilfs_add_checksums_on_logs(struct list_head *logs, u32 seed)
{ … }

/*
 * BIO operations
 */
static void nilfs_end_bio_write(struct bio *bio)
{ … }

static int nilfs_segbuf_submit_bio(struct nilfs_segment_buffer *segbuf,
				   struct nilfs_write_info *wi)
{ … }

static void nilfs_segbuf_prepare_write(struct nilfs_segment_buffer *segbuf,
				       struct nilfs_write_info *wi)
{ … }

static int nilfs_segbuf_submit_bh(struct nilfs_segment_buffer *segbuf,
				  struct nilfs_write_info *wi,
				  struct buffer_head *bh)
{ … }

/**
 * nilfs_segbuf_write - submit write requests of a log
 * @segbuf: buffer storing a log to be written
 * @nilfs: nilfs object
 *
 * Return Value: On Success, 0 is returned. On Error, one of the following
 * negative error code is returned.
 *
 * %-EIO - I/O error
 *
 * %-ENOMEM - Insufficient memory available.
 */
static int nilfs_segbuf_write(struct nilfs_segment_buffer *segbuf,
			      struct the_nilfs *nilfs)
{ … }

/**
 * nilfs_segbuf_wait - wait for completion of requested BIOs
 * @segbuf: segment buffer
 *
 * Return Value: On Success, 0 is returned. On Error, one of the following
 * negative error code is returned.
 *
 * %-EIO - I/O error
 */
static int nilfs_segbuf_wait(struct nilfs_segment_buffer *segbuf)
{ … }