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 */ 24 int 25 befs_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 59 int 60 befs_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