1/*
2 * linux/fs/befs/io.c
3 *
4 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
5 *
6 * Based on portions of file.c and inode.c
7 * by Makoto Kato (m_kato@ga2.so-net.ne.jp)
8 *
9 * Many thanks to Dominic Giampaolo, author of Practical File System
10 * Design with the Be File System, for such a helpful book.
11 *
12 */
13
14#include <linux/buffer_head.h>
15
16#include "befs.h"
17#include "io.h"
18
19/*
20 * Converts befs notion of disk addr to a disk offset and uses
21 * linux kernel function sb_bread() to get the buffer containing
22 * the offset. -Will Dyson
23 *
24 */
25
26struct buffer_head *
27befs_bread_iaddr(struct super_block *sb, befs_inode_addr iaddr)
28{
29	struct buffer_head *bh = NULL;
30	befs_blocknr_t block = 0;
31	struct befs_sb_info *befs_sb = BEFS_SB(sb);
32
33	befs_debug(sb, "---> Enter %s "
34		   "[%u, %hu, %hu]", __func__, iaddr.allocation_group,
35		   iaddr.start, iaddr.len);
36
37	if (iaddr.allocation_group > befs_sb->num_ags) {
38		befs_error(sb, "BEFS: Invalid allocation group %u, max is %u",
39			   iaddr.allocation_group, befs_sb->num_ags);
40		goto error;
41	}
42
43	block = iaddr2blockno(sb, &iaddr);
44
45	befs_debug(sb, "%s: offset = %lu", __func__, (unsigned long)block);
46
47	bh = sb_bread(sb, block);
48
49	if (bh == NULL) {
50		befs_error(sb, "Failed to read block %lu",
51			   (unsigned long)block);
52		goto error;
53	}
54
55	befs_debug(sb, "<--- %s", __func__);
56	return bh;
57
58      error:
59	befs_debug(sb, "<--- %s ERROR", __func__);
60	return NULL;
61}
62
63struct buffer_head *
64befs_bread(struct super_block *sb, befs_blocknr_t block)
65{
66	struct buffer_head *bh = NULL;
67
68	befs_debug(sb, "---> Enter %s %lu", __func__, (unsigned long)block);
69
70	bh = sb_bread(sb, block);
71
72	if (bh == NULL) {
73		befs_error(sb, "Failed to read block %lu",
74			   (unsigned long)block);
75		goto error;
76	}
77
78	befs_debug(sb, "<--- %s", __func__);
79
80	return bh;
81
82      error:
83	befs_debug(sb, "<--- %s ERROR", __func__);
84	return NULL;
85}
86