cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

super.c (3428B)

      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 */
     20int
     21befs_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
     57int
     58befs_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}