a8549fb5ab
The ocfs2_read_dir_block() function really maps an inode's virtual blocks to physical ones before calling ocfs2_read_blocks(). Let's extract that to common code, because other places might want to do that. Other than the block number being virtual, ocfs2_read_virt_blocks() takes the same arguments as ocfs2_read_blocks(). It converts those virtual block numbers to physical before calling ocfs2_read_blocks() directly. If the blocks asked for are discontiguous, this can mean multiple calls to ocfs2_read_blocks(), but this is mostly hidden from the caller. Like ocfs2_read_blocks(), the caller can pass in an existing buffer_head. This is usually done to pick up some readahead I/O. ocfs2_read_virt_blocks() checks the buffer_head's block number against the extent map - it must match. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
85 lines
2.5 KiB
C
85 lines
2.5 KiB
C
/* -*- mode: c; c-basic-offset: 8; -*-
|
|
* vim: noexpandtab sw=8 ts=8 sts=0:
|
|
*
|
|
* extent_map.h
|
|
*
|
|
* In-memory file extent mappings for OCFS2.
|
|
*
|
|
* Copyright (C) 2004 Oracle. All rights reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public
|
|
* License, version 2, as published by the Free Software Foundation.
|
|
*
|
|
* 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., 59 Temple Place - Suite 330,
|
|
* Boston, MA 021110-1307, USA.
|
|
*/
|
|
|
|
#ifndef _EXTENT_MAP_H
|
|
#define _EXTENT_MAP_H
|
|
|
|
struct ocfs2_extent_map_item {
|
|
unsigned int ei_cpos;
|
|
unsigned int ei_phys;
|
|
unsigned int ei_clusters;
|
|
unsigned int ei_flags;
|
|
|
|
struct list_head ei_list;
|
|
};
|
|
|
|
#define OCFS2_MAX_EXTENT_MAP_ITEMS 3
|
|
struct ocfs2_extent_map {
|
|
unsigned int em_num_items;
|
|
struct list_head em_list;
|
|
};
|
|
|
|
void ocfs2_extent_map_init(struct inode *inode);
|
|
void ocfs2_extent_map_trunc(struct inode *inode, unsigned int cluster);
|
|
void ocfs2_extent_map_insert_rec(struct inode *inode,
|
|
struct ocfs2_extent_rec *rec);
|
|
|
|
int ocfs2_get_clusters(struct inode *inode, u32 v_cluster, u32 *p_cluster,
|
|
u32 *num_clusters, unsigned int *extent_flags);
|
|
int ocfs2_extent_map_get_blocks(struct inode *inode, u64 v_blkno, u64 *p_blkno,
|
|
u64 *ret_count, unsigned int *extent_flags);
|
|
|
|
int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
|
|
u64 map_start, u64 map_len);
|
|
|
|
int ocfs2_xattr_get_clusters(struct inode *inode, u32 v_cluster,
|
|
u32 *p_cluster, u32 *num_clusters,
|
|
struct ocfs2_extent_list *el);
|
|
|
|
int ocfs2_read_virt_blocks(struct inode *inode, u64 v_block, int nr,
|
|
struct buffer_head *bhs[], int flags,
|
|
int (*validate)(struct super_block *sb,
|
|
struct buffer_head *bh));
|
|
static inline int ocfs2_read_virt_block(struct inode *inode, u64 v_block,
|
|
struct buffer_head **bh,
|
|
int (*validate)(struct super_block *sb,
|
|
struct buffer_head *bh))
|
|
{
|
|
int status = 0;
|
|
|
|
if (bh == NULL) {
|
|
printk("ocfs2: bh == NULL\n");
|
|
status = -EINVAL;
|
|
goto bail;
|
|
}
|
|
|
|
status = ocfs2_read_virt_blocks(inode, v_block, 1, bh, 0, validate);
|
|
|
|
bail:
|
|
return status;
|
|
}
|
|
|
|
|
|
#endif /* _EXTENT_MAP_H */
|