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