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