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brintos / linux-shallow public Read only

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1/*2 * super.c3 *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 fields18 * of the befs superblock19 */20int21befs_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 57int58befs_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 information93	 * 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 a104	 * different way, non-fatal consistency check105	 */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