1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * super.c
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun * Copyright (C) 2001-2002 Will Dyson <will_dyson@pobox.com>
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * Licensed under the GNU GPL. See the file COPYING for details.
7*4882a593Smuzhiyun *
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include <linux/fs.h>
11*4882a593Smuzhiyun #include <asm/page.h> /* for PAGE_SIZE */
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun #include "befs.h"
14*4882a593Smuzhiyun #include "super.h"
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun /*
17*4882a593Smuzhiyun * befs_load_sb -- Read from disk and properly byteswap all the fields
18*4882a593Smuzhiyun * of the befs superblock
19*4882a593Smuzhiyun */
20*4882a593Smuzhiyun int
befs_load_sb(struct super_block * sb,befs_super_block * disk_sb)21*4882a593Smuzhiyun befs_load_sb(struct super_block *sb, befs_super_block *disk_sb)
22*4882a593Smuzhiyun {
23*4882a593Smuzhiyun struct befs_sb_info *befs_sb = BEFS_SB(sb);
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun /* Check the byte order of the filesystem */
26*4882a593Smuzhiyun if (disk_sb->fs_byte_order == BEFS_BYTEORDER_NATIVE_LE)
27*4882a593Smuzhiyun befs_sb->byte_order = BEFS_BYTESEX_LE;
28*4882a593Smuzhiyun else if (disk_sb->fs_byte_order == BEFS_BYTEORDER_NATIVE_BE)
29*4882a593Smuzhiyun befs_sb->byte_order = BEFS_BYTESEX_BE;
30*4882a593Smuzhiyun
31*4882a593Smuzhiyun befs_sb->magic1 = fs32_to_cpu(sb, disk_sb->magic1);
32*4882a593Smuzhiyun befs_sb->magic2 = fs32_to_cpu(sb, disk_sb->magic2);
33*4882a593Smuzhiyun befs_sb->magic3 = fs32_to_cpu(sb, disk_sb->magic3);
34*4882a593Smuzhiyun befs_sb->block_size = fs32_to_cpu(sb, disk_sb->block_size);
35*4882a593Smuzhiyun befs_sb->block_shift = fs32_to_cpu(sb, disk_sb->block_shift);
36*4882a593Smuzhiyun befs_sb->num_blocks = fs64_to_cpu(sb, disk_sb->num_blocks);
37*4882a593Smuzhiyun befs_sb->used_blocks = fs64_to_cpu(sb, disk_sb->used_blocks);
38*4882a593Smuzhiyun befs_sb->inode_size = fs32_to_cpu(sb, disk_sb->inode_size);
39*4882a593Smuzhiyun
40*4882a593Smuzhiyun befs_sb->blocks_per_ag = fs32_to_cpu(sb, disk_sb->blocks_per_ag);
41*4882a593Smuzhiyun befs_sb->ag_shift = fs32_to_cpu(sb, disk_sb->ag_shift);
42*4882a593Smuzhiyun befs_sb->num_ags = fs32_to_cpu(sb, disk_sb->num_ags);
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun befs_sb->flags = fs32_to_cpu(sb, disk_sb->flags);
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun befs_sb->log_blocks = fsrun_to_cpu(sb, disk_sb->log_blocks);
47*4882a593Smuzhiyun befs_sb->log_start = fs64_to_cpu(sb, disk_sb->log_start);
48*4882a593Smuzhiyun befs_sb->log_end = fs64_to_cpu(sb, disk_sb->log_end);
49*4882a593Smuzhiyun
50*4882a593Smuzhiyun befs_sb->root_dir = fsrun_to_cpu(sb, disk_sb->root_dir);
51*4882a593Smuzhiyun befs_sb->indices = fsrun_to_cpu(sb, disk_sb->indices);
52*4882a593Smuzhiyun befs_sb->nls = NULL;
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun return BEFS_OK;
55*4882a593Smuzhiyun }
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun int
befs_check_sb(struct super_block * sb)58*4882a593Smuzhiyun befs_check_sb(struct super_block *sb)
59*4882a593Smuzhiyun {
60*4882a593Smuzhiyun struct befs_sb_info *befs_sb = BEFS_SB(sb);
61*4882a593Smuzhiyun
62*4882a593Smuzhiyun /* Check magic headers of super block */
63*4882a593Smuzhiyun if ((befs_sb->magic1 != BEFS_SUPER_MAGIC1)
64*4882a593Smuzhiyun || (befs_sb->magic2 != BEFS_SUPER_MAGIC2)
65*4882a593Smuzhiyun || (befs_sb->magic3 != BEFS_SUPER_MAGIC3)) {
66*4882a593Smuzhiyun befs_error(sb, "invalid magic header");
67*4882a593Smuzhiyun return BEFS_ERR;
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun /*
71*4882a593Smuzhiyun * Check blocksize of BEFS.
72*4882a593Smuzhiyun *
73*4882a593Smuzhiyun * Blocksize of BEFS is 1024, 2048, 4096 or 8192.
74*4882a593Smuzhiyun */
75*4882a593Smuzhiyun
76*4882a593Smuzhiyun if ((befs_sb->block_size != 1024)
77*4882a593Smuzhiyun && (befs_sb->block_size != 2048)
78*4882a593Smuzhiyun && (befs_sb->block_size != 4096)
79*4882a593Smuzhiyun && (befs_sb->block_size != 8192)) {
80*4882a593Smuzhiyun befs_error(sb, "invalid blocksize: %u", befs_sb->block_size);
81*4882a593Smuzhiyun return BEFS_ERR;
82*4882a593Smuzhiyun }
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun if (befs_sb->block_size > PAGE_SIZE) {
85*4882a593Smuzhiyun befs_error(sb, "blocksize(%u) cannot be larger "
86*4882a593Smuzhiyun "than system pagesize(%lu)", befs_sb->block_size,
87*4882a593Smuzhiyun PAGE_SIZE);
88*4882a593Smuzhiyun return BEFS_ERR;
89*4882a593Smuzhiyun }
90*4882a593Smuzhiyun
91*4882a593Smuzhiyun /*
92*4882a593Smuzhiyun * block_shift and block_size encode the same information
93*4882a593Smuzhiyun * in different ways as a consistency check.
94*4882a593Smuzhiyun */
95*4882a593Smuzhiyun
96*4882a593Smuzhiyun if ((1 << befs_sb->block_shift) != befs_sb->block_size) {
97*4882a593Smuzhiyun befs_error(sb, "block_shift disagrees with block_size. "
98*4882a593Smuzhiyun "Corruption likely.");
99*4882a593Smuzhiyun return BEFS_ERR;
100*4882a593Smuzhiyun }
101*4882a593Smuzhiyun
102*4882a593Smuzhiyun
103*4882a593Smuzhiyun /* ag_shift also encodes the same information as blocks_per_ag in a
104*4882a593Smuzhiyun * different way, non-fatal consistency check
105*4882a593Smuzhiyun */
106*4882a593Smuzhiyun if ((1 << befs_sb->ag_shift) != befs_sb->blocks_per_ag)
107*4882a593Smuzhiyun befs_error(sb, "ag_shift disagrees with blocks_per_ag.");
108*4882a593Smuzhiyun
109*4882a593Smuzhiyun if (befs_sb->log_start != befs_sb->log_end ||
110*4882a593Smuzhiyun befs_sb->flags == BEFS_DIRTY) {
111*4882a593Smuzhiyun befs_error(sb, "Filesystem not clean! There are blocks in the "
112*4882a593Smuzhiyun "journal. You must boot into BeOS and mount this "
113*4882a593Smuzhiyun "volume to make it clean.");
114*4882a593Smuzhiyun return BEFS_ERR;
115*4882a593Smuzhiyun }
116*4882a593Smuzhiyun
117*4882a593Smuzhiyun return BEFS_OK;
118*4882a593Smuzhiyun }
119