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
26 struct buffer_head *
befs_bread_iaddr(struct super_block * sb,befs_inode_addr iaddr)27 befs_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
63 struct buffer_head *
befs_bread(struct super_block * sb,befs_blocknr_t block)64 befs_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