1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * linux/fs/befs/io.c |
4 | * |
5 | * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com |
6 | * |
7 | * Based on portions of file.c and inode.c |
8 | * by Makoto Kato (m_kato@ga2.so-net.ne.jp) |
9 | * |
10 | * Many thanks to Dominic Giampaolo, author of Practical File System |
11 | * Design with the Be File System, for such a helpful book. |
12 | * |
13 | */ |
14 | |
15 | #include <linux/buffer_head.h> |
16 | |
17 | #include "befs.h" |
18 | #include "io.h" |
19 | |
20 | /* |
21 | * Converts befs notion of disk addr to a disk offset and uses |
22 | * linux kernel function sb_bread() to get the buffer containing |
23 | * the offset. |
24 | */ |
25 | |
26 | struct buffer_head * |
27 | befs_bread_iaddr(struct super_block *sb, befs_inode_addr iaddr) |
28 | { |
29 | struct buffer_head *bh; |
30 | befs_blocknr_t block; |
31 | struct befs_sb_info *befs_sb = BEFS_SB(super: sb); |
32 | |
33 | befs_debug(sb, fmt: "---> 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, fmt: "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: &iaddr); |
44 | |
45 | befs_debug(sb, fmt: "%s: offset = %lu" , __func__, (unsigned long)block); |
46 | |
47 | bh = sb_bread(sb, block); |
48 | |
49 | if (bh == NULL) { |
50 | befs_error(sb, fmt: "Failed to read block %lu" , |
51 | (unsigned long)block); |
52 | goto error; |
53 | } |
54 | |
55 | befs_debug(sb, fmt: "<--- %s" , __func__); |
56 | return bh; |
57 | |
58 | error: |
59 | befs_debug(sb, fmt: "<--- %s ERROR" , __func__); |
60 | return NULL; |
61 | } |
62 | |