kernel-ark/fs/nilfs2/bmap.h
Koji Sato bdb265eae0 nilfs2: integrated block mapping
This adds structures and operations for the block mapping (bmap for
short).  NILFS2 uses direct mappings for short files or B-tree based
mappings for longer files.

Every on-disk data block is held with inodes and managed through this
block mapping.  The nilfs_bmap structure and a set of functions here
provide this capability to the NILFS2 inode.

[penberg@cs.helsinki.fi: remove a bunch of bmap wrapper macros]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 08:31:13 -07:00

245 lines
7.7 KiB
C

/*
* bmap.h - NILFS block mapping.
*
* Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* Written by Koji Sato <koji@osrg.net>.
*/
#ifndef _NILFS_BMAP_H
#define _NILFS_BMAP_H
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/buffer_head.h>
#include <linux/nilfs2_fs.h>
#include "alloc.h"
#define NILFS_BMAP_INVALID_PTR 0
#define nilfs_bmap_dkey_to_key(dkey) le64_to_cpu(dkey)
#define nilfs_bmap_key_to_dkey(key) cpu_to_le64(key)
#define nilfs_bmap_dptr_to_ptr(dptr) le64_to_cpu(dptr)
#define nilfs_bmap_ptr_to_dptr(ptr) cpu_to_le64(ptr)
#define nilfs_bmap_keydiff_abs(diff) ((diff) < 0 ? -(diff) : (diff))
struct nilfs_bmap;
/**
* union nilfs_bmap_ptr_req - request for bmap ptr
* @bpr_ptr: bmap pointer
* @bpr_req: request for persistent allocator
*/
union nilfs_bmap_ptr_req {
__u64 bpr_ptr;
struct nilfs_palloc_req bpr_req;
};
/**
* struct nilfs_bmap_stats - bmap statistics
* @bs_nblocks: number of blocks created or deleted
*/
struct nilfs_bmap_stats {
unsigned int bs_nblocks;
};
/**
* struct nilfs_bmap_operations - bmap operation table
*/
struct nilfs_bmap_operations {
int (*bop_lookup)(const struct nilfs_bmap *, __u64, int, __u64 *);
int (*bop_insert)(struct nilfs_bmap *, __u64, __u64);
int (*bop_delete)(struct nilfs_bmap *, __u64);
void (*bop_clear)(struct nilfs_bmap *);
int (*bop_propagate)(const struct nilfs_bmap *, struct buffer_head *);
void (*bop_lookup_dirty_buffers)(struct nilfs_bmap *,
struct list_head *);
int (*bop_assign)(struct nilfs_bmap *,
struct buffer_head **,
sector_t,
union nilfs_binfo *);
int (*bop_mark)(struct nilfs_bmap *, __u64, int);
/* The following functions are internal use only. */
int (*bop_last_key)(const struct nilfs_bmap *, __u64 *);
int (*bop_check_insert)(const struct nilfs_bmap *, __u64);
int (*bop_check_delete)(struct nilfs_bmap *, __u64);
int (*bop_gather_data)(struct nilfs_bmap *, __u64 *, __u64 *, int);
};
/**
* struct nilfs_bmap_ptr_operations - bmap ptr operation table
*/
struct nilfs_bmap_ptr_operations {
int (*bpop_prepare_alloc_ptr)(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *);
void (*bpop_commit_alloc_ptr)(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *);
void (*bpop_abort_alloc_ptr)(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *);
int (*bpop_prepare_start_ptr)(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *);
void (*bpop_commit_start_ptr)(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *,
sector_t);
void (*bpop_abort_start_ptr)(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *);
int (*bpop_prepare_end_ptr)(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *);
void (*bpop_commit_end_ptr)(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *);
void (*bpop_abort_end_ptr)(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *);
int (*bpop_translate)(const struct nilfs_bmap *, __u64, __u64 *);
};
#define NILFS_BMAP_SIZE (NILFS_INODE_BMAP_SIZE * sizeof(__le64))
#define NILFS_BMAP_KEY_BIT (sizeof(unsigned long) * 8 /* CHAR_BIT */)
#define NILFS_BMAP_NEW_PTR_INIT \
(1UL << (sizeof(unsigned long) * 8 /* CHAR_BIT */ - 1))
static inline int nilfs_bmap_is_new_ptr(unsigned long ptr)
{
return !!(ptr & NILFS_BMAP_NEW_PTR_INIT);
}
/**
* struct nilfs_bmap - bmap structure
* @b_u: raw data
* @b_sem: semaphore
* @b_inode: owner of bmap
* @b_ops: bmap operation table
* @b_pops: bmap ptr operation table
* @b_low: low watermark of conversion
* @b_high: high watermark of conversion
* @b_last_allocated_key: last allocated key for data block
* @b_last_allocated_ptr: last allocated ptr for data block
* @b_state: state
*/
struct nilfs_bmap {
union {
__u8 u_flags;
__le64 u_data[NILFS_BMAP_SIZE / sizeof(__le64)];
} b_u;
struct rw_semaphore b_sem;
struct inode *b_inode;
const struct nilfs_bmap_operations *b_ops;
const struct nilfs_bmap_ptr_operations *b_pops;
__u64 b_low;
__u64 b_high;
__u64 b_last_allocated_key;
__u64 b_last_allocated_ptr;
int b_state;
};
/* state */
#define NILFS_BMAP_DIRTY 0x00000001
int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *);
int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *);
void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *);
int nilfs_bmap_lookup(struct nilfs_bmap *, unsigned long, unsigned long *);
int nilfs_bmap_insert(struct nilfs_bmap *, unsigned long, unsigned long);
int nilfs_bmap_delete(struct nilfs_bmap *, unsigned long);
int nilfs_bmap_last_key(struct nilfs_bmap *, unsigned long *);
int nilfs_bmap_truncate(struct nilfs_bmap *, unsigned long);
void nilfs_bmap_clear(struct nilfs_bmap *);
int nilfs_bmap_propagate(struct nilfs_bmap *, struct buffer_head *);
void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *, struct list_head *);
int nilfs_bmap_assign(struct nilfs_bmap *, struct buffer_head **,
unsigned long, union nilfs_binfo *);
int nilfs_bmap_lookup_at_level(struct nilfs_bmap *, __u64, int, __u64 *);
int nilfs_bmap_mark(struct nilfs_bmap *, __u64, int);
void nilfs_bmap_init_gc(struct nilfs_bmap *);
void nilfs_bmap_init_gcdat(struct nilfs_bmap *, struct nilfs_bmap *);
void nilfs_bmap_commit_gcdat(struct nilfs_bmap *, struct nilfs_bmap *);
/*
* Internal use only
*/
int nilfs_bmap_move_v(const struct nilfs_bmap *, __u64, sector_t);
int nilfs_bmap_mark_dirty(const struct nilfs_bmap *, __u64);
__u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *,
const struct buffer_head *);
__u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *, __u64);
__u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *);
int nilfs_bmap_prepare_update(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *,
union nilfs_bmap_ptr_req *);
void nilfs_bmap_commit_update(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *,
union nilfs_bmap_ptr_req *);
void nilfs_bmap_abort_update(struct nilfs_bmap *,
union nilfs_bmap_ptr_req *,
union nilfs_bmap_ptr_req *);
void nilfs_bmap_add_blocks(const struct nilfs_bmap *, int);
void nilfs_bmap_sub_blocks(const struct nilfs_bmap *, int);
int nilfs_bmap_get_block(const struct nilfs_bmap *, __u64,
struct buffer_head **);
void nilfs_bmap_put_block(const struct nilfs_bmap *, struct buffer_head *);
int nilfs_bmap_get_new_block(const struct nilfs_bmap *, __u64,
struct buffer_head **);
void nilfs_bmap_delete_block(const struct nilfs_bmap *, struct buffer_head *);
/* Assume that bmap semaphore is locked. */
static inline int nilfs_bmap_dirty(const struct nilfs_bmap *bmap)
{
return !!(bmap->b_state & NILFS_BMAP_DIRTY);
}
/* Assume that bmap semaphore is locked. */
static inline void nilfs_bmap_set_dirty(struct nilfs_bmap *bmap)
{
bmap->b_state |= NILFS_BMAP_DIRTY;
}
/* Assume that bmap semaphore is locked. */
static inline void nilfs_bmap_clear_dirty(struct nilfs_bmap *bmap)
{
bmap->b_state &= ~NILFS_BMAP_DIRTY;
}
#define NILFS_BMAP_LARGE 0x1
#define NILFS_BMAP_SMALL_LOW NILFS_DIRECT_KEY_MIN
#define NILFS_BMAP_SMALL_HIGH NILFS_DIRECT_KEY_MAX
#define NILFS_BMAP_LARGE_LOW NILFS_BTREE_ROOT_NCHILDREN_MAX
#define NILFS_BMAP_LARGE_HIGH NILFS_BTREE_KEY_MAX
#endif /* _NILFS_BMAP_H */