1/*
2 * super.c
3 *
4 * Copyright (C) 2001-2002 Will Dyson <will_dyson@pobox.com>
5 *
6 * Licensed under the GNU GPL. See the file COPYING for details.
7 *
8 */
9
10#include <linux/fs.h>
11#include <asm/page.h> /* for PAGE_SIZE */
12
13#include "befs.h"
14#include "super.h"
15
16/**
17 * load_befs_sb -- Read from disk and properly byteswap all the fields
18 * of the befs superblock
19 *
20 *
21 *
22 *
23 */
24int
25befs_load_sb(struct super_block *sb, befs_super_block * disk_sb)
26{
27	struct befs_sb_info *befs_sb = BEFS_SB(sb);
28
29	/* Check the byte order of the filesystem */
30	if (disk_sb->fs_byte_order == BEFS_BYTEORDER_NATIVE_LE)
31	    befs_sb->byte_order = BEFS_BYTESEX_LE;
32	else if (disk_sb->fs_byte_order == BEFS_BYTEORDER_NATIVE_BE)
33	    befs_sb->byte_order = BEFS_BYTESEX_BE;
34
35	befs_sb->magic1 = fs32_to_cpu(sb, disk_sb->magic1);
36	befs_sb->magic2 = fs32_to_cpu(sb, disk_sb->magic2);
37	befs_sb->magic3 = fs32_to_cpu(sb, disk_sb->magic3);
38	befs_sb->block_size = fs32_to_cpu(sb, disk_sb->block_size);
39	befs_sb->block_shift = fs32_to_cpu(sb, disk_sb->block_shift);
40	befs_sb->num_blocks = fs64_to_cpu(sb, disk_sb->num_blocks);
41	befs_sb->used_blocks = fs64_to_cpu(sb, disk_sb->used_blocks);
42	befs_sb->inode_size = fs32_to_cpu(sb, disk_sb->inode_size);
43
44	befs_sb->blocks_per_ag = fs32_to_cpu(sb, disk_sb->blocks_per_ag);
45	befs_sb->ag_shift = fs32_to_cpu(sb, disk_sb->ag_shift);
46	befs_sb->num_ags = fs32_to_cpu(sb, disk_sb->num_ags);
47
48	befs_sb->log_blocks = fsrun_to_cpu(sb, disk_sb->log_blocks);
49	befs_sb->log_start = fs64_to_cpu(sb, disk_sb->log_start);
50	befs_sb->log_end = fs64_to_cpu(sb, disk_sb->log_end);
51
52	befs_sb->root_dir = fsrun_to_cpu(sb, disk_sb->root_dir);
53	befs_sb->indices = fsrun_to_cpu(sb, disk_sb->indices);
54	befs_sb->nls = NULL;
55
56	return BEFS_OK;
57}
58
59int
60befs_check_sb(struct super_block *sb)
61{
62	struct befs_sb_info *befs_sb = BEFS_SB(sb);
63
64	/* Check magic headers of super block */
65	if ((befs_sb->magic1 != BEFS_SUPER_MAGIC1)
66	    || (befs_sb->magic2 != BEFS_SUPER_MAGIC2)
67	    || (befs_sb->magic3 != BEFS_SUPER_MAGIC3)) {
68		befs_error(sb, "invalid magic header");
69		return BEFS_ERR;
70	}
71
72	/*
73	 * Check blocksize of BEFS.
74	 *
75	 * Blocksize of BEFS is 1024, 2048, 4096 or 8192.
76	 */
77
78	if ((befs_sb->block_size != 1024)
79	    && (befs_sb->block_size != 2048)
80	    && (befs_sb->block_size != 4096)
81	    && (befs_sb->block_size != 8192)) {
82		befs_error(sb, "invalid blocksize: %u", befs_sb->block_size);
83		return BEFS_ERR;
84	}
85
86	if (befs_sb->block_size > PAGE_SIZE) {
87		befs_error(sb, "blocksize(%u) cannot be larger"
88			   "than system pagesize(%lu)", befs_sb->block_size,
89			   PAGE_SIZE);
90		return BEFS_ERR;
91	}
92
93	/*
94	   * block_shift and block_size encode the same information
95	   * in different ways as a consistency check.
96	 */
97
98	if ((1 << befs_sb->block_shift) != befs_sb->block_size) {
99		befs_error(sb, "block_shift disagrees with block_size. "
100			   "Corruption likely.");
101		return BEFS_ERR;
102	}
103
104	if (befs_sb->log_start != befs_sb->log_end) {
105		befs_error(sb, "Filesystem not clean! There are blocks in the "
106			   "journal. You must boot into BeOS and mount this volume "
107			   "to make it clean.");
108		return BEFS_ERR;
109	}
110
111	return BEFS_OK;
112}
113