linux/fs/nilfs2/bmap.h
Ryusuke Konishi 5ad2686e92 nilfs2: get maximum number of child nodes from bmap object
The patch "reduce repetitive calculation of max number of child nodes"
gathered up the calculation of maximum number of child nodes into
nilfs_btree_nchildren_per_block() function.  This makes the function
get resultant value from a private variable in bmap object instead of
calculating it for each call.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-07-23 10:02:14 +09:00

268 lines
7.9 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"
#include "dat.h"
#define NILFS_BMAP_INVALID_PTR 0
#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_lookup_contig)(const struct nilfs_bmap *, __u64, __u64 *,
unsigned);
int (*bop_insert)(struct nilfs_bmap *, __u64, __u64);
int (*bop_delete)(struct nilfs_bmap *, __u64);
void (*bop_clear)(struct nilfs_bmap *);
int (*bop_propagate)(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);
};
#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_last_allocated_key: last allocated key for data block
* @b_last_allocated_ptr: last allocated ptr for data block
* @b_ptr_type: pointer type
* @b_state: state
* @b_nchildren_per_block: maximum number of child nodes for non-root nodes
*/
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;
__u64 b_last_allocated_key;
__u64 b_last_allocated_ptr;
int b_ptr_type;
int b_state;
__u16 b_nchildren_per_block;
};
/* pointer type */
#define NILFS_BMAP_PTR_P 0 /* physical block number (i.e. LBN) */
#define NILFS_BMAP_PTR_VS 1 /* virtual block number (single
version) */
#define NILFS_BMAP_PTR_VM 2 /* virtual block number (has multiple
versions) */
#define NILFS_BMAP_PTR_U (-1) /* never perform pointer operations */
#define NILFS_BMAP_USE_VBN(bmap) ((bmap)->b_ptr_type > 0)
/* 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_contig(struct nilfs_bmap *, __u64, __u64 *, unsigned);
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 *);
static inline int nilfs_bmap_lookup(struct nilfs_bmap *bmap, __u64 key,
__u64 *ptr)
{
return nilfs_bmap_lookup_at_level(bmap, key, 1, ptr);
}
/*
* Internal use only
*/
struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *);
static inline int nilfs_bmap_prepare_alloc_ptr(struct nilfs_bmap *bmap,
union nilfs_bmap_ptr_req *req,
struct inode *dat)
{
if (dat)
return nilfs_dat_prepare_alloc(dat, &req->bpr_req);
/* ignore target ptr */
req->bpr_ptr = bmap->b_last_allocated_ptr++;
return 0;
}
static inline void nilfs_bmap_commit_alloc_ptr(struct nilfs_bmap *bmap,
union nilfs_bmap_ptr_req *req,
struct inode *dat)
{
if (dat)
nilfs_dat_commit_alloc(dat, &req->bpr_req);
}
static inline void nilfs_bmap_abort_alloc_ptr(struct nilfs_bmap *bmap,
union nilfs_bmap_ptr_req *req,
struct inode *dat)
{
if (dat)
nilfs_dat_abort_alloc(dat, &req->bpr_req);
else
bmap->b_last_allocated_ptr--;
}
static inline int nilfs_bmap_prepare_end_ptr(struct nilfs_bmap *bmap,
union nilfs_bmap_ptr_req *req,
struct inode *dat)
{
return dat ? nilfs_dat_prepare_end(dat, &req->bpr_req) : 0;
}
static inline void nilfs_bmap_commit_end_ptr(struct nilfs_bmap *bmap,
union nilfs_bmap_ptr_req *req,
struct inode *dat)
{
if (dat)
nilfs_dat_commit_end(dat, &req->bpr_req,
bmap->b_ptr_type == NILFS_BMAP_PTR_VS);
}
static inline void nilfs_bmap_abort_end_ptr(struct nilfs_bmap *bmap,
union nilfs_bmap_ptr_req *req,
struct inode *dat)
{
if (dat)
nilfs_dat_abort_end(dat, &req->bpr_req);
}
static inline void nilfs_bmap_set_target_v(struct nilfs_bmap *bmap, __u64 key,
__u64 ptr)
{
bmap->b_last_allocated_key = key;
bmap->b_last_allocated_ptr = ptr;
}
__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 *);
void nilfs_bmap_add_blocks(const struct nilfs_bmap *, int);
void nilfs_bmap_sub_blocks(const struct nilfs_bmap *, int);
/* 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 */