Ejemplo n.º 1
0
struct ext2_group_desc *
get_group_desc(struct mount *mp, unsigned int block_group,
	       struct buf **bh)
{
	struct ext2_sb_info *sb = VFSTOEXT2(mp)->um_e2fs;
	unsigned long group_desc;
	unsigned long desc;
	struct ext2_group_desc *gdp;

	if (block_group >= sb->s_groups_count)
		panic ("get_group_desc: "
			    "block_group >= groups_count - "
			    "block_group = %d, groups_count = %lu",
			    block_group, sb->s_groups_count);

	group_desc = block_group / EXT2_DESC_PER_BLOCK(sb);
	desc = block_group % EXT2_DESC_PER_BLOCK(sb);
	if (!sb->s_group_desc[group_desc])
		panic ( "get_group_desc:"
			    "Group descriptor not loaded - "
			    "block_group = %d, group_desc = %lu, desc = %lu",
			     block_group, group_desc, desc);
	gdp = (struct ext2_group_desc *)
		sb->s_group_desc[group_desc]->b_data;
	if (bh)
		*bh = sb->s_group_desc[group_desc];
	return gdp + desc;
}
Ejemplo n.º 2
0
static struct ext2_group_desc * get_group_desc (struct super_block * sb,
						unsigned int block_group,
						struct buffer_head ** bh)
{
	unsigned long group_desc;
	unsigned long desc;
	struct ext2_group_desc * gdp;

	if (block_group >= sb->u.ext2_sb.s_groups_count)
		ext2_panic (sb, "get_group_desc",
			    "block_group >= groups_count - "
			    "block_group = %d, groups_count = %lu",
			    block_group, sb->u.ext2_sb.s_groups_count);

	group_desc = block_group / EXT2_DESC_PER_BLOCK(sb);
	desc = block_group % EXT2_DESC_PER_BLOCK(sb);
	if (!sb->u.ext2_sb.s_group_desc[group_desc])
		ext2_panic (sb, "get_group_desc",
			    "Group descriptor not loaded - "
			    "block_group = %d, group_desc = %lu, desc = %lu",
			     block_group, group_desc, desc);
	gdp = (struct ext2_group_desc *) 
		sb->u.ext2_sb.s_group_desc[group_desc]->b_data;
	if (bh)
		*bh = sb->u.ext2_sb.s_group_desc[group_desc];
	return gdp + desc;
}
Ejemplo n.º 3
0
int op_statfs (const char *path, struct statvfs *buf)
{
	unsigned long long i;
	unsigned long long s_gdb_count = 0;
	unsigned long long s_groups_count = 0;
	unsigned long long s_itb_per_group = 0;
	unsigned long long s_overhead_last = 0;
	unsigned long long s_inodes_per_block = 0;

	ext2_filsys e2fs;
	FUSE_EXT2_LOCK;
	e2fs	= current_ext2fs();

	debugf("enter");

	memset(buf, 0, sizeof(struct statvfs));

	if (e2fs->super->s_default_mount_opts & EXT2_MOUNT_MINIX_DF) {
		s_overhead_last = 0;
	} else {
		s_overhead_last = e2fs->super->s_first_data_block;
		s_groups_count = ((EXT2_BLOCKS_COUNT(e2fs->super) - e2fs->super->s_first_data_block - 1) / e2fs->super->s_blocks_per_group) + 1;
		s_gdb_count = (s_groups_count + EXT2_DESC_PER_BLOCK(e2fs->super) - 1) / EXT2_DESC_PER_BLOCK(e2fs->super);
		for (i = 0; i < s_groups_count; i++) {
			s_overhead_last += ext2_bg_has_super(e2fs, i) + ((ext2_bg_num_gdb(e2fs, i) == 0) ? 0 : s_gdb_count);
		}
		s_inodes_per_block = EXT2_BLOCK_SIZE(e2fs->super) / EXT2_INODE_SIZE(e2fs->super);
		s_itb_per_group = e2fs->super->s_inodes_per_group / s_inodes_per_block;
		s_overhead_last += (s_groups_count * (2 +  s_itb_per_group));
	}
	buf->f_bsize = EXT2_BLOCK_SIZE(e2fs->super);
	buf->f_frsize = /*EXT2_FRAG_SIZE(e2fs->super);*/ buf->f_bsize;
	buf->f_blocks = EXT2_BLOCKS_COUNT(e2fs->super) - s_overhead_last;
	buf->f_bfree = EXT2_FBLOCKS_COUNT(e2fs->super);
	if (EXT2_FBLOCKS_COUNT(e2fs->super) < EXT2_RBLOCKS_COUNT(e2fs->super)) {
		buf->f_bavail = 0;
	} else {
		buf->f_bavail = EXT2_FBLOCKS_COUNT(e2fs->super) - EXT2_RBLOCKS_COUNT(e2fs->super);
	}
	buf->f_files = e2fs->super->s_inodes_count;
	buf->f_ffree = e2fs->super->s_free_inodes_count;
	buf->f_favail = e2fs->super->s_free_inodes_count;
	buf->f_namemax = EXT2_NAME_LEN;

	debugf("leave");
	FUSE_EXT2_UNLOCK;
	return 0;
}
Ejemplo n.º 4
0
/*
 * ext2fs_super_and_bgd_loc2()
 * @fs:			ext2 fs pointer
 * @group		given block group
 * @ret_super_blk:	if !NULL, returns super block location
 * @ret_old_desc_blk:	if !NULL, returns location of the old block
 *			group descriptor
 * @ret_new_desc_blk:	if !NULL, returns location of meta_bg block
 *			group descriptor
 * @ret_used_blks:	if !NULL, returns number of blocks used by
 *			super block and group_descriptors.
 *
 * Returns errcode_t of 0
 */
errcode_t ext2fs_super_and_bgd_loc2(ext2_filsys fs,
					   dgrp_t group,
					   blk64_t *ret_super_blk,
					   blk64_t *ret_old_desc_blk,
					   blk64_t *ret_new_desc_blk,
					   blk_t *ret_used_blks)
{
	blk64_t	group_block, super_blk = 0, old_desc_blk = 0, new_desc_blk = 0;
	unsigned int meta_bg, meta_bg_size;
	blk_t	numblocks = 0;
	blk64_t old_desc_blocks;
	int	has_super;

	group_block = ext2fs_group_first_block2(fs, group);
	if (group_block == 0 && fs->blocksize == 1024)
		group_block = 1; /* Deal with 1024 blocksize && bigalloc */

	if (ext2fs_has_feature_meta_bg(fs->super))
		old_desc_blocks = fs->super->s_first_meta_bg;
	else
		old_desc_blocks =
			fs->desc_blocks + fs->super->s_reserved_gdt_blocks;

	has_super = ext2fs_bg_has_super(fs, group);

	if (has_super) {
		super_blk = group_block;
		numblocks++;
	}
	meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
	meta_bg = group / meta_bg_size;

	if (!ext2fs_has_feature_meta_bg(fs->super) ||
	    (meta_bg < fs->super->s_first_meta_bg)) {
		if (has_super) {
			old_desc_blk = group_block + 1;
			numblocks += old_desc_blocks;
		}
	} else {
		if (((group % meta_bg_size) == 0) ||
		    ((group % meta_bg_size) == 1) ||
		    ((group % meta_bg_size) == (meta_bg_size-1))) {
			if (has_super)
				has_super = 1;
			new_desc_blk = group_block + has_super;
			numblocks++;
		}
	}

	if (ret_super_blk)
		*ret_super_blk = super_blk;
	if (ret_old_desc_blk)
		*ret_old_desc_blk = old_desc_blk;
	if (ret_new_desc_blk)
		*ret_new_desc_blk = new_desc_blk;
	if (ret_used_blks)
		*ret_used_blks = numblocks;

	return 0;
}
Ejemplo n.º 5
0
/*
 * Calculate the number of GDT blocks to reserve for online filesystem growth.
 * The absolute maximum number of GDT blocks we can reserve is determined by
 * the number of block pointers that can fit into a single block.
 */
static unsigned int calc_reserved_gdt_blocks(ext2_filsys fs)
{
	struct ext2_super_block *sb = fs->super;
	unsigned long bpg = sb->s_blocks_per_group;
	unsigned int gdpb = EXT2_DESC_PER_BLOCK(sb);
	unsigned long max_blocks = 0xffffffff;
	unsigned long rsv_groups;
	unsigned int rsv_gdb;

	/* We set it at 1024x the current filesystem size, or
	 * the upper block count limit (2^32), whichever is lower.
	 */
	if (ext2fs_blocks_count(sb) < max_blocks / 1024)
		max_blocks = ext2fs_blocks_count(sb) * 1024;
	/*
	 * ext2fs_div64_ceil() is unnecessary because max_blocks is
	 * max _GDT_ blocks, which is limited to 32 bits.
	 */
	rsv_groups = ext2fs_div_ceil(max_blocks - sb->s_first_data_block, bpg);
	rsv_gdb = ext2fs_div_ceil(rsv_groups, gdpb) - fs->desc_blocks;
	if (rsv_gdb > EXT2_ADDR_PER_BLOCK(sb))
		rsv_gdb = EXT2_ADDR_PER_BLOCK(sb);
#ifdef RES_GDT_DEBUG
	printf("max_blocks %lu, rsv_groups = %lu, rsv_gdb = %u\n",
	       max_blocks, rsv_groups, rsv_gdb);
#endif

	return rsv_gdb;
}
Ejemplo n.º 6
0
struct ext2_group_desc * ext2_get_group_desc(struct super_block * sb,
					     unsigned int block_group,
					     struct buffer_head ** bh)
{
	unsigned long group_desc;
	unsigned long offset;
	struct ext2_group_desc * desc;
	struct ext2_sb_info *sbi = EXT2_SB(sb);

	if (block_group >= sbi->s_groups_count) {
		ext2_error (sb, "ext2_get_group_desc",
			    "block_group >= groups_count - "
			    "block_group = %d, groups_count = %lu",
			    block_group, sbi->s_groups_count);

		return NULL;
	}

	group_desc = block_group >> EXT2_DESC_PER_BLOCK_BITS(sb);
	offset = block_group & (EXT2_DESC_PER_BLOCK(sb) - 1);
	if (!sbi->s_group_desc[group_desc]) {
		ext2_error (sb, "ext2_get_group_desc",
			    "Group descriptor not loaded - "
			    "block_group = %d, group_desc = %lu, desc = %lu",
			     block_group, group_desc, offset);
		return NULL;
	}

	desc = (struct ext2_group_desc *) sbi->s_group_desc[group_desc]->b_data;
	if (bh)
		*bh = sbi->s_group_desc[group_desc];
	return desc + offset;
}
Ejemplo n.º 7
0
blk_t ext2fs_descriptor_block_loc(ext2_filsys fs, blk_t group_block, dgrp_t i)
{
	int	bg;
	int	has_super = 0;
	int	ret_blk;

	if (!(fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) ||
	    (i < fs->super->s_first_meta_bg))
		return (group_block + i + 1);

	bg = EXT2_DESC_PER_BLOCK(fs->super) * i;
	if (ext2fs_bg_has_super(fs, bg))
		has_super = 1;
	ret_blk = ext2fs_group_first_block(fs, bg) + has_super;
	/*
	 * If group_block is not the normal value, we're trying to use
	 * the backup group descriptors and superblock --- so use the
	 * alternate location of the second block group in the
	 * metablock group.  Ideally we should be testing each bg
	 * descriptor block individually for correctness, but we don't
	 * have the infrastructure in place to do that.
	 */
	if (group_block != fs->super->s_first_data_block &&
	    ((ret_blk + fs->super->s_blocks_per_group) <
	     fs->super->s_blocks_count))
		ret_blk += fs->super->s_blocks_per_group;
	return ret_blk;
}
Ejemplo n.º 8
0
/*
 * ext2fs_super_and_bgd_loc2()
 * @fs:			ext2 fs pointer
 * @group		given block group
 * @ret_super_blk:	if !NULL, returns super block location
 * @ret_old_desc_blk:	if !NULL, returns location of the old block
 *			group descriptor
 * @ret_new_desc_blk:	if !NULL, returns location of meta_bg block
 *			group descriptor
 * @ret_used_blks:	if !NULL, returns number of blocks used by
 *			super block and group_descriptors.
 *
 * Returns errcode_t of 0
 */
errcode_t ext2fs_super_and_bgd_loc2(ext2_filsys fs,
					   dgrp_t group,
					   blk64_t *ret_super_blk,
					   blk64_t *ret_old_desc_blk,
					   blk64_t *ret_new_desc_blk,
					   blk_t *ret_used_blks)
{
	blk64_t	group_block, super_blk = 0, old_desc_blk = 0, new_desc_blk = 0;
	unsigned int meta_bg, meta_bg_size;
	blk_t	numblocks = 0;
	blk64_t old_desc_blocks;
	int	has_super;

	group_block = ext2fs_group_first_block2(fs, group);

	if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
		old_desc_blocks = fs->super->s_first_meta_bg;
	else
		old_desc_blocks =
			fs->desc_blocks + fs->super->s_reserved_gdt_blocks;

	has_super = ext2fs_bg_has_super(fs, group);

	if (has_super) {
		super_blk = group_block;
		numblocks++;
	}
	meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
	meta_bg = group / meta_bg_size;

	if (!(fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) ||
	    (meta_bg < fs->super->s_first_meta_bg)) {
		if (has_super) {
			old_desc_blk = group_block + 1;
			numblocks += old_desc_blocks;
		}
	} else {
		if (((group % meta_bg_size) == 0) ||
		    ((group % meta_bg_size) == 1) ||
		    ((group % meta_bg_size) == (meta_bg_size-1))) {
			if (has_super)
				has_super = 1;
			new_desc_blk = group_block + has_super;
			numblocks++;
		}
	}

	if (ret_super_blk)
		*ret_super_blk = super_blk;
	if (ret_old_desc_blk)
		*ret_old_desc_blk = old_desc_blk;
	if (ret_new_desc_blk)
		*ret_new_desc_blk = new_desc_blk;
	if (ret_used_blks)
		*ret_used_blks = numblocks;

	return 0;
}
Ejemplo n.º 9
0
static int ext2_check_descriptors (struct super_block * sb)
{
	int i;
	int desc_block = 0;
	struct ext2_sb_info *sbi = EXT2_SB(sb);
	struct ext2_group_desc * gdp = NULL;

	ext2_debug ("Checking group descriptors");

	for (i = 0; i < sbi->s_groups_count; i++)
	{
		ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
		ext2_fsblk_t last_block;

		if (i == sbi->s_groups_count - 1)
			last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
		else
			last_block = first_block +
				(EXT2_BLOCKS_PER_GROUP(sb) - 1);

		if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
			gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
		if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
		    le32_to_cpu(gdp->bg_block_bitmap) > last_block)
		{
			ext2_error (sb, "ext2_check_descriptors",
				    "Block bitmap for group %d"
				    " not in group (block %lu)!",
				    i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
			return 0;
		}
		if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
		    le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
		{
			ext2_error (sb, "ext2_check_descriptors",
				    "Inode bitmap for group %d"
				    " not in group (block %lu)!",
				    i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
			return 0;
		}
		if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
		    le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
		    last_block)
		{
			ext2_error (sb, "ext2_check_descriptors",
				    "Inode table for group %d"
				    " not in group (block %lu)!",
				    i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
			return 0;
		}
		gdp++;
	}
	return 1;
}
Ejemplo n.º 10
0
void ext2_get_group_desc(ext2_VOLUME* volume,
		   int group_id, struct ext2_group_desc *gdp)
{
	unsigned int block, offset;
	struct ext2_group_desc *le_gdp;

	block = 1 + volume->super->s_first_data_block;
	block += group_id / EXT2_DESC_PER_BLOCK(volume->super);
	ext2_read_block(volume,  block);

	offset = group_id % EXT2_DESC_PER_BLOCK(volume->super);
	offset *= sizeof(*gdp);

	le_gdp = (struct ext2_group_desc *)(volume->buffer + offset);

	gdp->bg_block_bitmap = __le32_to_cpu(le_gdp->bg_block_bitmap);
	gdp->bg_inode_bitmap = __le32_to_cpu(le_gdp->bg_inode_bitmap);
	gdp->bg_inode_table = __le32_to_cpu(le_gdp->bg_inode_table);
	gdp->bg_free_blocks_count = __le16_to_cpu(le_gdp->bg_free_blocks_count);
	gdp->bg_free_inodes_count = __le16_to_cpu(le_gdp->bg_free_inodes_count);
	gdp->bg_used_dirs_count = __le16_to_cpu(le_gdp->bg_used_dirs_count);
}
Ejemplo n.º 11
0
/*
 * Checks that the data in the descriptor blocks make sense.
 */
int
ext2_check_descriptors(struct ext2_sb_info *sb)
{
        int i;
        int desc_block = 0;
        unsigned long block = sb->s_es->s_first_data_block;
        struct ext2_group_desc *gdp = NULL;

        /* ext2_debug ("Checking group descriptors"); */

        for (i = 0; i < sb->s_groups_count; i++)
        {
		/* examine next descriptor block */
                if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
                        gdp = (struct ext2_group_desc *)
				sb->s_group_desc[desc_block++]->b_data;
                if (gdp->bg_block_bitmap < block ||
                    gdp->bg_block_bitmap >= block + EXT2_BLOCKS_PER_GROUP(sb))
                {
                        kprintf ("ext2_check_descriptors: "
                                    "Block bitmap for group %d"
                                    " not in group (block %lu)!\n",
                                    i, (unsigned long) gdp->bg_block_bitmap);
                        return 0;
                }
                if (gdp->bg_inode_bitmap < block ||
                    gdp->bg_inode_bitmap >= block + EXT2_BLOCKS_PER_GROUP(sb))
                {
                        kprintf ("ext2_check_descriptors: "
                                    "Inode bitmap for group %d"
                                    " not in group (block %lu)!\n",
                                    i, (unsigned long) gdp->bg_inode_bitmap);
                        return 0;
                }
                if (gdp->bg_inode_table < block ||
                    gdp->bg_inode_table + sb->s_itb_per_group >=
                    block + EXT2_BLOCKS_PER_GROUP(sb))
                {
                        kprintf ("ext2_check_descriptors: "
                                    "Inode table for group %d"
                                    " not in group (block %lu)!\n",
                                    i, (unsigned long) gdp->bg_inode_table);
                        return 0;
                }
                block += EXT2_BLOCKS_PER_GROUP(sb);
                gdp++;
        }
        return 1;
}
Ejemplo n.º 12
0
blk64_t ext2fs_descriptor_block_loc2(ext2_filsys fs, blk64_t group_block,
				     dgrp_t i)
{
	int	bg;
	int	has_super = 0, group_zero_adjust = 0;
	blk64_t	ret_blk;

	/*
	 * On a bigalloc FS with 1K blocks, block 0 is reserved for non-ext4
	 * stuff, so adjust for that if we're being asked for group 0.
	 */
	if (i == 0 && fs->blocksize == 1024 && EXT2FS_CLUSTER_RATIO(fs) > 1)
		group_zero_adjust = 1;

	if (!ext2fs_has_feature_meta_bg(fs->super) ||
	    (i < fs->super->s_first_meta_bg))
		return group_block + i + 1 + group_zero_adjust;

	bg = EXT2_DESC_PER_BLOCK(fs->super) * i;
	if (ext2fs_bg_has_super(fs, bg))
		has_super = 1;
	ret_blk = ext2fs_group_first_block2(fs, bg);
	/*
	 * If group_block is not the normal value, we're trying to use
	 * the backup group descriptors and superblock --- so use the
	 * alternate location of the second block group in the
	 * metablock group.  Ideally we should be testing each bg
	 * descriptor block individually for correctness, but we don't
	 * have the infrastructure in place to do that.
	 */
	if (group_block != fs->super->s_first_data_block &&
	    ((ret_blk + has_super + fs->super->s_blocks_per_group) <
	     ext2fs_blocks_count(fs->super))) {
		ret_blk += fs->super->s_blocks_per_group;

		/*
		 * If we're going to jump forward a block group, make sure
		 * that we adjust has_super to account for the next group's
		 * backup superblock (or lack thereof).
		 */
		if (ext2fs_bg_has_super(fs, bg + 1))
			has_super = 1;
		else
			has_super = 0;
	}
	return ret_blk + has_super + group_zero_adjust;
}
Ejemplo n.º 13
0
static int ext2_check_descriptors (struct super_block * sb)
{
	int i;
	int desc_block = 0;
	unsigned long block = le32_to_cpu(sb->u.ext2_sb.s_es->s_first_data_block);
	struct ext2_group_desc * gdp = NULL;

	ext2_debug ("Checking group descriptors");

	for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++)
	{
		if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
			gdp = (struct ext2_group_desc *) sb->u.ext2_sb.s_group_desc[desc_block++]->b_data;
		if (le32_to_cpu(gdp->bg_block_bitmap) < block ||
		    le32_to_cpu(gdp->bg_block_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
		{
			ext2_error (sb, "ext2_check_descriptors",
				    "Block bitmap for group %d"
				    " not in group (block %lu)!",
				    i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
			return 0;
		}
		if (le32_to_cpu(gdp->bg_inode_bitmap) < block ||
		    le32_to_cpu(gdp->bg_inode_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
		{
			ext2_error (sb, "ext2_check_descriptors",
				    "Inode bitmap for group %d"
				    " not in group (block %lu)!",
				    i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
			return 0;
		}
		if (le32_to_cpu(gdp->bg_inode_table) < block ||
		    le32_to_cpu(gdp->bg_inode_table) + sb->u.ext2_sb.s_itb_per_group >=
		    block + EXT2_BLOCKS_PER_GROUP(sb))
		{
			ext2_error (sb, "ext2_check_descriptors",
				    "Inode table for group %d"
				    " not in group (block %lu)!",
				    i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
			return 0;
		}
		block += EXT2_BLOCKS_PER_GROUP(sb);
		gdp++;
	}
	return 1;
}
Ejemplo n.º 14
0
/*
 * This function returns the location of the superblock, block group
 * descriptors for a given block group.  It currently returns the
 * number of free blocks assuming that inode table and allocation
 * bitmaps will be in the group.  This is not necessarily the case
 * when the flex_bg feature is enabled, so callers should take care!
 * It was only really intended for use by mke2fs, and even there it's
 * not that useful.
 *
 * The ext2fs_super_and_bgd_loc2() function is 64-bit block number
 * capable and returns the number of blocks used by super block and
 * group descriptors.
 */
int ext2fs_super_and_bgd_loc(ext2_filsys fs,
			     dgrp_t group,
			     blk_t *ret_super_blk,
			     blk_t *ret_old_desc_blk,
			     blk_t *ret_new_desc_blk,
			     int *ret_meta_bg)
{
	blk64_t ret_super_blk2;
	blk64_t ret_old_desc_blk2;
	blk64_t ret_new_desc_blk2;
	blk_t ret_used_blks;
	blk_t numblocks;
	unsigned int meta_bg_size;

	ext2fs_super_and_bgd_loc2(fs, group, &ret_super_blk2,
					&ret_old_desc_blk2,
					&ret_new_desc_blk2,
					&ret_used_blks);

	if (group == fs->group_desc_count-1) {
		numblocks = (fs->super->s_blocks_count -
			     fs->super->s_first_data_block) %
			fs->super->s_blocks_per_group;
		if (!numblocks)
			numblocks = fs->super->s_blocks_per_group;
	} else
		numblocks = fs->super->s_blocks_per_group;

	if (ret_super_blk)
		*ret_super_blk = (blk_t)ret_super_blk2;
	if (ret_old_desc_blk)
		*ret_old_desc_blk = (blk_t)ret_old_desc_blk2;
	if (ret_new_desc_blk)
		*ret_new_desc_blk = (blk_t)ret_new_desc_blk2;
	if (ret_meta_bg) {
		meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
		*ret_meta_bg = group / meta_bg_size;
	}

	numblocks -= 2 + fs->inode_blocks_per_group + ret_used_blks;

	return numblocks;
}
Ejemplo n.º 15
0
static errcode_t adjust_fs_size(ext2_filsys fs, long long *new_size)
{
    errcode_t	retval;
    int    overhead = 0;
    int    rem;

    fs->super->s_blocks_count = (unsigned int)(*new_size / fs->blocksize);

retry:
    fs->group_desc_count = ext2fs_div_ceil(fs->super->s_blocks_count -
			       fs->super->s_first_data_block, EXT2_BLOCKS_PER_GROUP(fs->super));
    if (fs->group_desc_count == 0)
        return EXT2_ET_TOOSMALL;
    fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count, EXT2_DESC_PER_BLOCK(fs->super));

    /*
    * Overhead is the number of bookkeeping blocks per group.  It
    * includes the superblock backup, the group descriptor
    * backups, the inode bitmap, the block bitmap, and the inode
    * table.
    */
    overhead = (int) (2 + fs->inode_blocks_per_group);

    if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1))
        overhead += 1 + fs->desc_blocks + fs->super->s_reserved_gdt_blocks;

    /*
    * See if the last group is big enough to support the
    * necessary data structures.  If not, we need to get rid of
    * it.
    */
    rem = (fs->super->s_blocks_count - fs->super->s_first_data_block) % fs->super->s_blocks_per_group;
    if ((fs->group_desc_count == 1) && rem && (rem < overhead))
        return EXT2_ET_TOOSMALL;

    if (rem && (rem < overhead+50)) {
        fs->super->s_blocks_count -= rem;
        goto retry;
    }

    *new_size = ((long long)fs->super->s_blocks_count * (long long)fs->blocksize);
    return 0;
}
Ejemplo n.º 16
0
/*
 * This function returns the location of the superblock, block group
 * descriptors for a given block group.  It currently returns the
 * number of free blocks assuming that inode table and allocation
 * bitmaps will be in the group.  This is not necessarily the case
 * when the flex_bg feature is enabled, so callers should take care!
 * It was only really intended for use by mke2fs, and even there it's
 * not that useful.
 *
 * The ext2fs_super_and_bgd_loc2() function is 64-bit block number
 * capable and returns the number of blocks used by super block and
 * group descriptors.
 */
int ext2fs_super_and_bgd_loc(ext2_filsys fs,
			     dgrp_t group,
			     blk_t *ret_super_blk,
			     blk_t *ret_old_desc_blk,
			     blk_t *ret_new_desc_blk,
			     int *ret_meta_bg)
{
	blk64_t ret_super_blk2;
	blk64_t ret_old_desc_blk2;
	blk64_t ret_new_desc_blk2;
	blk_t ret_used_blks;
	blk_t numblocks;
	unsigned int meta_bg_size;

	ext2fs_super_and_bgd_loc2(fs, group, &ret_super_blk2,
					&ret_old_desc_blk2,
					&ret_new_desc_blk2,
					&ret_used_blks);

	numblocks = ext2fs_group_blocks_count(fs, group);

	if (ret_super_blk)
		*ret_super_blk = (blk_t)ret_super_blk2;
	if (ret_old_desc_blk)
		*ret_old_desc_blk = (blk_t)ret_old_desc_blk2;
	if (ret_new_desc_blk)
		*ret_new_desc_blk = (blk_t)ret_new_desc_blk2;
	if (ret_meta_bg) {
		meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
		*ret_meta_bg = group / meta_bg_size;
	}

	numblocks -= 2 + fs->inode_blocks_per_group + ret_used_blks;

	return numblocks;
}
Ejemplo n.º 17
0
/*
 *  Note: if superblock is non-zero, block-size must also be non-zero.
 * 	Superblock and block_size can be zero to use the default size.
 *
 * Valid flags for ext2fs_open()
 * 
 * 	EXT2_FLAG_RW	- Open the filesystem for read/write.
 * 	EXT2_FLAG_FORCE - Open the filesystem even if some of the
 *				features aren't supported.
 *	EXT2_FLAG_JOURNAL_DEV_OK - Open an ext3 journal device
 */
errcode_t ext2fs_open2(const char *name, const char *io_options,
		       int flags, int superblock,
		       unsigned int block_size, io_manager manager, 
		       ext2_filsys *ret_fs)
{
	ext2_filsys	fs;
	errcode_t	retval;
	unsigned long	i;
	int		groups_per_block, blocks_per_group;
	blk_t		group_block, blk;
	char		*dest, *cp;
#ifdef EXT2FS_ENABLE_SWAPFS
	int j;
	struct ext2_group_desc *gdp;
#endif
	
	EXT2_CHECK_MAGIC(manager, EXT2_ET_MAGIC_IO_MANAGER);

	retval = ext2fs_get_mem(sizeof(struct struct_ext2_filsys), &fs);
	if (retval)
		return retval;
	
	memset(fs, 0, sizeof(struct struct_ext2_filsys));
	fs->magic = EXT2_ET_MAGIC_EXT2FS_FILSYS;
	fs->flags = flags;
	fs->umask = 022;
	retval = ext2fs_get_mem(strlen(name)+1, &fs->device_name);
	if (retval)
		goto cleanup;
	strcpy(fs->device_name, name);
	cp = strchr(fs->device_name, '?');
	if (!io_options && cp) {
		*cp++ = 0;
		io_options = cp;
	}
		
	retval = manager->open(fs->device_name, 
			       (flags & EXT2_FLAG_RW) ? IO_FLAG_RW : 0,
			       &fs->io);
	if (retval)
		goto cleanup;
	if (io_options && 
	    (retval = io_channel_set_options(fs->io, io_options)))
		goto cleanup;
	fs->image_io = fs->io;
	fs->io->app_data = fs;
	retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &fs->super);
	if (retval)
		goto cleanup;
	if (flags & EXT2_FLAG_IMAGE_FILE) {
		retval = ext2fs_get_mem(sizeof(struct ext2_image_hdr),
					&fs->image_header);
		if (retval)
			goto cleanup;
		retval = io_channel_read_blk(fs->io, 0,
					     -(int)sizeof(struct ext2_image_hdr),
					     fs->image_header);
		if (retval)
			goto cleanup;
		if (fs->image_header->magic_number != EXT2_ET_MAGIC_E2IMAGE)
			return EXT2_ET_MAGIC_E2IMAGE;
		superblock = 1;
		block_size = fs->image_header->fs_blocksize;
	}

	/*
	 * If the user specifies a specific block # for the
	 * superblock, then he/she must also specify the block size!
	 * Otherwise, read the master superblock located at offset
	 * SUPERBLOCK_OFFSET from the start of the partition.
	 *
	 * Note: we only save a backup copy of the superblock if we
	 * are reading the superblock from the primary superblock location.
	 */
	if (superblock) {
		if (!block_size) {
			retval = EXT2_ET_INVALID_ARGUMENT;
			goto cleanup;
		}
		io_channel_set_blksize(fs->io, block_size);
		group_block = superblock;
		fs->orig_super = 0;
	} else {
		io_channel_set_blksize(fs->io, SUPERBLOCK_OFFSET);
		superblock = 1;
		group_block = 0;
		retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &fs->orig_super);
		if (retval)
			goto cleanup;
	}
	retval = io_channel_read_blk(fs->io, superblock, -SUPERBLOCK_SIZE,
				     fs->super);
	if (retval)
		goto cleanup;
	if (fs->orig_super)
		memcpy(fs->orig_super, fs->super, SUPERBLOCK_SIZE);

#ifdef EXT2FS_ENABLE_SWAPFS
	if ((fs->super->s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC)) ||
	    (fs->flags & EXT2_FLAG_SWAP_BYTES)) {
		fs->flags |= EXT2_FLAG_SWAP_BYTES;

		ext2fs_swap_super(fs->super);
	}
#endif
	
	if (fs->super->s_magic != EXT2_SUPER_MAGIC) {
		retval = EXT2_ET_BAD_MAGIC;
		goto cleanup;
	}
	if (fs->super->s_rev_level > EXT2_LIB_CURRENT_REV) {
		retval = EXT2_ET_REV_TOO_HIGH;
		goto cleanup;
	}

	/*
	 * Check for feature set incompatibility
	 */
	if (!(flags & EXT2_FLAG_FORCE)) {
		if (fs->super->s_feature_incompat &
		    ~EXT2_LIB_FEATURE_INCOMPAT_SUPP) {
			retval = EXT2_ET_UNSUPP_FEATURE;
			goto cleanup;
		}
		if ((flags & EXT2_FLAG_RW) &&
		    (fs->super->s_feature_ro_compat &
		     ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP)) {
			retval = EXT2_ET_RO_UNSUPP_FEATURE;
			goto cleanup;
		}
		if (!(flags & EXT2_FLAG_JOURNAL_DEV_OK) &&
		    (fs->super->s_feature_incompat &
		     EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)) {
			retval = EXT2_ET_UNSUPP_FEATURE;
			goto cleanup;
		}
	}
	
	fs->blocksize = EXT2_BLOCK_SIZE(fs->super);
	if (fs->blocksize == 0) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->fragsize = EXT2_FRAG_SIZE(fs->super);
	fs->inode_blocks_per_group = ((fs->super->s_inodes_per_group *
				       EXT2_INODE_SIZE(fs->super) +
				       EXT2_BLOCK_SIZE(fs->super) - 1) /
				      EXT2_BLOCK_SIZE(fs->super));
	if (block_size) {
		if (block_size != fs->blocksize) {
			retval = EXT2_ET_UNEXPECTED_BLOCK_SIZE;
			goto cleanup;
		}
	}
	/*
	 * Set the blocksize to the filesystem's blocksize.
	 */
	io_channel_set_blksize(fs->io, fs->blocksize);

	/*
	 * If this is an external journal device, don't try to read
	 * the group descriptors, because they're not there.
	 */
	if (fs->super->s_feature_incompat &
	    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) {
		fs->group_desc_count = 0;
		*ret_fs = fs;
		return 0;
	}
	
	/*
	 * Read group descriptors
	 */
	blocks_per_group = EXT2_BLOCKS_PER_GROUP(fs->super);
	if (blocks_per_group == 0 ||
	    blocks_per_group > EXT2_MAX_BLOCKS_PER_GROUP(fs->super) ||
	    fs->inode_blocks_per_group > EXT2_MAX_INODES_PER_GROUP(fs->super)) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->group_desc_count = (fs->super->s_blocks_count -
				fs->super->s_first_data_block +
				blocks_per_group - 1) / blocks_per_group;
	fs->desc_blocks = (fs->group_desc_count +
			   EXT2_DESC_PER_BLOCK(fs->super) - 1)
		/ EXT2_DESC_PER_BLOCK(fs->super);
	retval = ext2fs_get_mem(fs->desc_blocks * fs->blocksize,
				&fs->group_desc);
	if (retval)
		goto cleanup;
	if (!group_block)
		group_block = fs->super->s_first_data_block;
	dest = (char *) fs->group_desc;
	groups_per_block = fs->blocksize / sizeof(struct ext2_group_desc);
	for (i=0 ; i < fs->desc_blocks; i++) {
		blk = ext2fs_descriptor_block_loc(fs, group_block, i);
		retval = io_channel_read_blk(fs->io, blk, 1, dest);
		if (retval)
			goto cleanup;
#ifdef EXT2FS_ENABLE_SWAPFS
		if (fs->flags & EXT2_FLAG_SWAP_BYTES) {
			gdp = (struct ext2_group_desc *) dest;
			for (j=0; j < groups_per_block; j++)
				ext2fs_swap_group_desc(gdp++);
		}
#endif
		dest += fs->blocksize;
	}

	*ret_fs = fs;
	return 0;
cleanup:
	ext2fs_free(fs);
	return retval;
}
Ejemplo n.º 18
0
errcode_t ext2fs_flush2(ext2_filsys fs, int flags)
{
	dgrp_t		i;
	errcode_t	retval;
	unsigned long	fs_state;
	__u32		feature_incompat;
	struct ext2_super_block *super_shadow = 0;
	struct ext2_group_desc *group_shadow = 0;
#ifdef WORDS_BIGENDIAN
	struct ext2_group_desc *gdp;
	dgrp_t		j;
#endif
	char	*group_ptr;
	blk64_t	old_desc_blocks;
	struct ext2fs_numeric_progress_struct progress;

	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);

	fs_state = fs->super->s_state;
	feature_incompat = fs->super->s_feature_incompat;

	fs->super->s_wtime = fs->now ? fs->now : time(NULL);
	fs->super->s_block_group_nr = 0;

	/*
	 * If the write_bitmaps() function is present, call it to
	 * flush the bitmaps.  This is done this way so that a simple
	 * program that doesn't mess with the bitmaps doesn't need to
	 * drag in the bitmaps.c code.
	 *
	 * Bitmap checksums live in the group descriptor, so the
	 * bitmaps need to be written before the descriptors.
	 */
	if (fs->write_bitmaps) {
		retval = fs->write_bitmaps(fs);
		if (retval)
			goto errout;
	}

	/* Prepare the group descriptors for writing */
#ifdef WORDS_BIGENDIAN
	retval = EXT2_ET_NO_MEMORY;
	retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &super_shadow);
	if (retval)
		goto errout;
	retval = ext2fs_get_array(fs->desc_blocks, fs->blocksize,
				  &group_shadow);
	if (retval)
		goto errout;
	memcpy(super_shadow, fs->super, sizeof(struct ext2_super_block));
	memcpy(group_shadow, fs->group_desc, (size_t) fs->blocksize *
	       fs->desc_blocks);

	/* swap the group descriptors */
	for (j = 0; j < fs->group_desc_count; j++) {
		gdp = ext2fs_group_desc(fs, group_shadow, j);
		ext2fs_swap_group_desc2(fs, gdp);
	}
#else
	super_shadow = fs->super;
	group_shadow = ext2fs_group_desc(fs, fs->group_desc, 0);
#endif

	/*
	 * Set the state of the FS to be non-valid.  (The state has
	 * already been backed up earlier, and will be restored after
	 * we write out the backup superblocks.)
	 */
	fs->super->s_state &= ~EXT2_VALID_FS;
	ext2fs_clear_feature_journal_needs_recovery(fs->super);

	/*
	 * If this is an external journal device, don't write out the
	 * block group descriptors or any of the backup superblocks
	 */
	if (ext2fs_has_feature_journal_dev(fs->super))
		goto write_primary_superblock_only;

	/*
	 * Write out the master group descriptors, and the backup
	 * superblocks and group descriptors.
	 */
	group_ptr = (char *) group_shadow;
	if (ext2fs_has_feature_meta_bg(fs->super)) {
		old_desc_blocks = fs->super->s_first_meta_bg;
		if (old_desc_blocks > fs->desc_blocks)
			old_desc_blocks = fs->desc_blocks;
	} else
		old_desc_blocks = fs->desc_blocks;

	if (fs->progress_ops && fs->progress_ops->init)
		(fs->progress_ops->init)(fs, &progress, NULL,
					 fs->group_desc_count);


	for (i = 0; i < fs->group_desc_count; i++) {
		blk64_t	super_blk, old_desc_blk, new_desc_blk;

		if (fs->progress_ops && fs->progress_ops->update)
			(fs->progress_ops->update)(fs, &progress, i);
		ext2fs_super_and_bgd_loc2(fs, i, &super_blk, &old_desc_blk,
					 &new_desc_blk, 0);

		if (!(fs->flags & EXT2_FLAG_MASTER_SB_ONLY) &&i && super_blk) {
			retval = write_backup_super(fs, i, super_blk,
						    super_shadow);
			if (retval)
				goto errout;
		}
		if (fs->flags & EXT2_FLAG_SUPER_ONLY)
			continue;
		if ((old_desc_blk) &&
		    (!(fs->flags & EXT2_FLAG_MASTER_SB_ONLY) || (i == 0))) {
			retval = io_channel_write_blk64(fs->io,
			      old_desc_blk, old_desc_blocks, group_ptr);
			if (retval)
				goto errout;
		}
		if (new_desc_blk) {
			int meta_bg = i / EXT2_DESC_PER_BLOCK(fs->super);

			retval = io_channel_write_blk64(fs->io, new_desc_blk,
				1, group_ptr + (meta_bg*fs->blocksize));
			if (retval)
				goto errout;
		}
	}

	if (fs->progress_ops && fs->progress_ops->close)
		(fs->progress_ops->close)(fs, &progress, NULL);

write_primary_superblock_only:
	/*
	 * Write out master superblock.  This has to be done
	 * separately, since it is located at a fixed location
	 * (SUPERBLOCK_OFFSET).  We flush all other pending changes
	 * out to disk first, just to avoid a race condition with an
	 * insy-tinsy window....
	 */

	fs->super->s_block_group_nr = 0;
	fs->super->s_state = fs_state;
	fs->super->s_feature_incompat = feature_incompat;
#ifdef WORDS_BIGENDIAN
	*super_shadow = *fs->super;
	ext2fs_swap_super(super_shadow);
#endif

	retval = ext2fs_superblock_csum_set(fs, super_shadow);
	if (retval)
		return retval;

	if (!(flags & EXT2_FLAG_FLUSH_NO_SYNC))
		retval = io_channel_flush(fs->io);
	retval = write_primary_superblock(fs, super_shadow);
	if (retval)
		goto errout;

	fs->flags &= ~EXT2_FLAG_DIRTY;

	if (!(flags & EXT2_FLAG_FLUSH_NO_SYNC))
		retval = io_channel_flush(fs->io);
errout:
	fs->super->s_state = fs_state;
#ifdef WORDS_BIGENDIAN
	if (super_shadow)
		ext2fs_free_mem(&super_shadow);
	if (group_shadow)
		ext2fs_free_mem(&group_shadow);
#endif
	return retval;
}
Ejemplo n.º 19
0
/*
 * This function returns the location of the superblock, block group
 * descriptors for a given block group.  It currently returns the
 * number of free blocks assuming that inode table and allocation
 * bitmaps will be in the group.  This is not necessarily the case
 * when the flex_bg feature is enabled, so callers should take care!
 * It was only really intended for use by mke2fs, and even there it's
 * not that useful.  In the future, when we redo this function for
 * 64-bit block numbers, we should probably return the number of
 * blocks used by the super block and group descriptors instead.
 *
 * See also the comment for ext2fs_reserve_super_and_bgd()
 */
int ext2fs_super_and_bgd_loc(ext2_filsys fs,
			     dgrp_t group,
			     blk_t *ret_super_blk,
			     blk_t *ret_old_desc_blk,
			     blk_t *ret_new_desc_blk,
			     int *ret_meta_bg)
{
	blk_t	group_block, super_blk = 0, old_desc_blk = 0, new_desc_blk = 0;
	unsigned int meta_bg, meta_bg_size;
	blk_t	numblocks, old_desc_blocks;
	int	has_super;

	group_block = ext2fs_group_first_block(fs, group);

	if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
		old_desc_blocks = fs->super->s_first_meta_bg;
	else
		old_desc_blocks =
			fs->desc_blocks + fs->super->s_reserved_gdt_blocks;

	if (group == fs->group_desc_count-1) {
		numblocks = (fs->super->s_blocks_count -
			     fs->super->s_first_data_block) %
			fs->super->s_blocks_per_group;
		if (!numblocks)
			numblocks = fs->super->s_blocks_per_group;
	} else
		numblocks = fs->super->s_blocks_per_group;

	has_super = ext2fs_bg_has_super(fs, group);

	if (has_super) {
		super_blk = group_block;
		numblocks--;
	}
	meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
	meta_bg = group / meta_bg_size;

	if (!(fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) ||
	    (meta_bg < fs->super->s_first_meta_bg)) {
		if (has_super) {
			old_desc_blk = group_block + 1;
			numblocks -= old_desc_blocks;
		}
	} else {
		if (((group % meta_bg_size) == 0) ||
		    ((group % meta_bg_size) == 1) ||
		    ((group % meta_bg_size) == (meta_bg_size-1))) {
			if (has_super)
				has_super = 1;
			new_desc_blk = group_block + has_super;
			numblocks--;
		}
	}

	numblocks -= 2 + fs->inode_blocks_per_group;

	if (ret_super_blk)
		*ret_super_blk = super_blk;
	if (ret_old_desc_blk)
		*ret_old_desc_blk = old_desc_blk;
	if (ret_new_desc_blk)
		*ret_new_desc_blk = new_desc_blk;
	if (ret_meta_bg)
		*ret_meta_bg = meta_bg;
	return (numblocks);
}
Ejemplo n.º 20
0
static int ext2_fill_super(struct super_block *sb, void *data, int silent)
{
	struct buffer_head * bh;
	struct ext2_sb_info * sbi;
	struct ext2_super_block * es;
	struct inode *root;
	unsigned long block;
	unsigned long sb_block = get_sb_block(&data);
	unsigned long logic_sb_block;
	unsigned long offset = 0;
	unsigned long def_mount_opts;
	long ret = -EINVAL;
	int blocksize = BLOCK_SIZE;
	int db_count;
	int i, j;
	__le32 features;
	int err;

	err = -ENOMEM;
	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
	if (!sbi)
		goto failed;

	sbi->s_blockgroup_lock =
		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
	if (!sbi->s_blockgroup_lock) {
		kfree(sbi);
		goto failed;
	}
	sb->s_fs_info = sbi;
	sbi->s_sb_block = sb_block;

	spin_lock_init(&sbi->s_lock);

	/*
	 * See what the current blocksize for the device is, and
	 * use that as the blocksize.  Otherwise (or if the blocksize
	 * is smaller than the default) use the default.
	 * This is important for devices that have a hardware
	 * sectorsize that is larger than the default.
	 */
	blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
	if (!blocksize) {
		ext2_msg(sb, KERN_ERR, "error: unable to set blocksize");
		goto failed_sbi;
	}

	/*
	 * If the superblock doesn't start on a hardware sector boundary,
	 * calculate the offset.  
	 */
	if (blocksize != BLOCK_SIZE) {
		logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
		offset = (sb_block*BLOCK_SIZE) % blocksize;
	} else {
		logic_sb_block = sb_block;
	}

	if (!(bh = sb_bread(sb, logic_sb_block))) {
		ext2_msg(sb, KERN_ERR, "error: unable to read superblock");
		goto failed_sbi;
	}
	/*
	 * Note: s_es must be initialized as soon as possible because
	 *       some ext2 macro-instructions depend on its value
	 */
	es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
	sbi->s_es = es;
	sb->s_magic = le16_to_cpu(es->s_magic);

	if (sb->s_magic != EXT2_SUPER_MAGIC)
		goto cantfind_ext2;

	/* Set defaults before we parse the mount options */
	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
	if (def_mount_opts & EXT2_DEFM_DEBUG)
		set_opt(sbi->s_mount_opt, DEBUG);
	if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
		set_opt(sbi->s_mount_opt, GRPID);
	if (def_mount_opts & EXT2_DEFM_UID16)
		set_opt(sbi->s_mount_opt, NO_UID32);
#ifdef CONFIG_EXT2_FS_XATTR
	if (def_mount_opts & EXT2_DEFM_XATTR_USER)
		set_opt(sbi->s_mount_opt, XATTR_USER);
#endif
#ifdef CONFIG_EXT2_FS_POSIX_ACL
	if (def_mount_opts & EXT2_DEFM_ACL)
		set_opt(sbi->s_mount_opt, POSIX_ACL);
#endif
	
	if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
		set_opt(sbi->s_mount_opt, ERRORS_PANIC);
	else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
		set_opt(sbi->s_mount_opt, ERRORS_CONT);
	else
		set_opt(sbi->s_mount_opt, ERRORS_RO);

	sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
	sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
	
	set_opt(sbi->s_mount_opt, RESERVATION);

	if (!parse_options((char *) data, sb))
		goto failed_mount;

	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
		((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
		 MS_POSIXACL : 0);
	sb->s_iflags |= SB_I_CGROUPWB;

	if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
	    (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
	     EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
	     EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
		ext2_msg(sb, KERN_WARNING,
			"warning: feature flags set on rev 0 fs, "
			"running e2fsck is recommended");
	/*
	 * Check feature flags regardless of the revision level, since we
	 * previously didn't change the revision level when setting the flags,
	 * so there is a chance incompat flags are set on a rev 0 filesystem.
	 */
	features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
	if (features) {
		ext2_msg(sb, KERN_ERR,	"error: couldn't mount because of "
		       "unsupported optional features (%x)",
			le32_to_cpu(features));
		goto failed_mount;
	}
	if (!(sb->s_flags & MS_RDONLY) &&
	    (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
		ext2_msg(sb, KERN_ERR, "error: couldn't mount RDWR because of "
		       "unsupported optional features (%x)",
		       le32_to_cpu(features));
		goto failed_mount;
	}

	blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);

	if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
		struct blk_dax_ctl dax = {
			.sector = 0,
			.size = PAGE_SIZE,
		};
		if (blocksize != PAGE_SIZE) {
			ext2_msg(sb, KERN_ERR,
					"error: unsupported blocksize for dax");
			goto failed_mount;
		}
		err = bdev_direct_access(sb->s_bdev, &dax);
		if (err < 0) {
			switch (err) {
			case -EOPNOTSUPP:
				ext2_msg(sb, KERN_ERR,
					"error: device does not support dax");
				break;
			case -EINVAL:
				ext2_msg(sb, KERN_ERR,
					"error: unaligned partition for dax");
				break;
			default:
				ext2_msg(sb, KERN_ERR,
					"error: dax access failed (%d)", err);
				break;
			}
			goto failed_mount;
		}
	}

	/* If the blocksize doesn't match, re-read the thing.. */
	if (sb->s_blocksize != blocksize) {
		brelse(bh);

		if (!sb_set_blocksize(sb, blocksize)) {
			ext2_msg(sb, KERN_ERR,
				"error: bad blocksize %d", blocksize);
			goto failed_sbi;
		}

		logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
		offset = (sb_block*BLOCK_SIZE) % blocksize;
		bh = sb_bread(sb, logic_sb_block);
		if(!bh) {
			ext2_msg(sb, KERN_ERR, "error: couldn't read"
				"superblock on 2nd try");
			goto failed_sbi;
		}
		es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
		sbi->s_es = es;
		if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
			ext2_msg(sb, KERN_ERR, "error: magic mismatch");
			goto failed_mount;
		}
	}

	sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
	sb->s_max_links = EXT2_LINK_MAX;

	if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
		sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
		sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
	} else {
		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
		if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
		    !is_power_of_2(sbi->s_inode_size) ||
		    (sbi->s_inode_size > blocksize)) {
			ext2_msg(sb, KERN_ERR,
				"error: unsupported inode size: %d",
				sbi->s_inode_size);
			goto failed_mount;
		}
	}

	sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
				   le32_to_cpu(es->s_log_frag_size);
	if (sbi->s_frag_size == 0)
		goto cantfind_ext2;
	sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;

	sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
	sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
	sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);

	if (EXT2_INODE_SIZE(sb) == 0)
		goto cantfind_ext2;
	sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
	if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
		goto cantfind_ext2;
	sbi->s_itb_per_group = sbi->s_inodes_per_group /
					sbi->s_inodes_per_block;
	sbi->s_desc_per_block = sb->s_blocksize /
					sizeof (struct ext2_group_desc);
	sbi->s_sbh = bh;
	sbi->s_mount_state = le16_to_cpu(es->s_state);
	sbi->s_addr_per_block_bits =
		ilog2 (EXT2_ADDR_PER_BLOCK(sb));
	sbi->s_desc_per_block_bits =
		ilog2 (EXT2_DESC_PER_BLOCK(sb));

	if (sb->s_magic != EXT2_SUPER_MAGIC)
		goto cantfind_ext2;

	if (sb->s_blocksize != bh->b_size) {
		if (!silent)
			ext2_msg(sb, KERN_ERR, "error: unsupported blocksize");
		goto failed_mount;
	}

	if (sb->s_blocksize != sbi->s_frag_size) {
		ext2_msg(sb, KERN_ERR,
			"error: fragsize %lu != blocksize %lu"
			"(not supported yet)",
			sbi->s_frag_size, sb->s_blocksize);
		goto failed_mount;
	}

	if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
		ext2_msg(sb, KERN_ERR,
			"error: #blocks per group too big: %lu",
			sbi->s_blocks_per_group);
		goto failed_mount;
	}
	if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
		ext2_msg(sb, KERN_ERR,
			"error: #fragments per group too big: %lu",
			sbi->s_frags_per_group);
		goto failed_mount;
	}
	if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
		ext2_msg(sb, KERN_ERR,
			"error: #inodes per group too big: %lu",
			sbi->s_inodes_per_group);
		goto failed_mount;
	}

	if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
		goto cantfind_ext2;
 	sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
 				le32_to_cpu(es->s_first_data_block) - 1)
 					/ EXT2_BLOCKS_PER_GROUP(sb)) + 1;
	db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
		   EXT2_DESC_PER_BLOCK(sb);
	sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
	if (sbi->s_group_desc == NULL) {
		ext2_msg(sb, KERN_ERR, "error: not enough memory");
		goto failed_mount;
	}
	bgl_lock_init(sbi->s_blockgroup_lock);
	sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
	if (!sbi->s_debts) {
		ext2_msg(sb, KERN_ERR, "error: not enough memory");
		goto failed_mount_group_desc;
	}
	for (i = 0; i < db_count; i++) {
		block = descriptor_loc(sb, logic_sb_block, i);
		sbi->s_group_desc[i] = sb_bread(sb, block);
		if (!sbi->s_group_desc[i]) {
			for (j = 0; j < i; j++)
				brelse (sbi->s_group_desc[j]);
			ext2_msg(sb, KERN_ERR,
				"error: unable to read group descriptors");
			goto failed_mount_group_desc;
		}
	}
	if (!ext2_check_descriptors (sb)) {
		ext2_msg(sb, KERN_ERR, "group descriptors corrupted");
		goto failed_mount2;
	}
	sbi->s_gdb_count = db_count;
	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
	spin_lock_init(&sbi->s_next_gen_lock);

	/* per fileystem reservation list head & lock */
	spin_lock_init(&sbi->s_rsv_window_lock);
	sbi->s_rsv_window_root = RB_ROOT;
	/*
	 * Add a single, static dummy reservation to the start of the
	 * reservation window list --- it gives us a placeholder for
	 * append-at-start-of-list which makes the allocation logic
	 * _much_ simpler.
	 */
	sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
	sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
	sbi->s_rsv_window_head.rsv_alloc_hit = 0;
	sbi->s_rsv_window_head.rsv_goal_size = 0;
	ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);

	err = percpu_counter_init(&sbi->s_freeblocks_counter,
				ext2_count_free_blocks(sb), GFP_KERNEL);
	if (!err) {
		err = percpu_counter_init(&sbi->s_freeinodes_counter,
				ext2_count_free_inodes(sb), GFP_KERNEL);
	}
	if (!err) {
		err = percpu_counter_init(&sbi->s_dirs_counter,
				ext2_count_dirs(sb), GFP_KERNEL);
	}
	if (err) {
		ext2_msg(sb, KERN_ERR, "error: insufficient memory");
		goto failed_mount3;
	}

#ifdef CONFIG_EXT2_FS_XATTR
	sbi->s_mb_cache = ext2_xattr_create_cache();
	if (!sbi->s_mb_cache) {
		ext2_msg(sb, KERN_ERR, "Failed to create an mb_cache");
		goto failed_mount3;
	}
#endif
	/*
	 * set up enough so that it can read an inode
	 */
	sb->s_op = &ext2_sops;
	sb->s_export_op = &ext2_export_ops;
	sb->s_xattr = ext2_xattr_handlers;

#ifdef CONFIG_QUOTA
	sb->dq_op = &dquot_operations;
	sb->s_qcop = &dquot_quotactl_ops;
	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
#endif

	root = ext2_iget(sb, EXT2_ROOT_INO);
	if (IS_ERR(root)) {
		ret = PTR_ERR(root);
		goto failed_mount3;
	}
	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
		iput(root);
		ext2_msg(sb, KERN_ERR, "error: corrupt root inode, run e2fsck");
		goto failed_mount3;
	}

	sb->s_root = d_make_root(root);
	if (!sb->s_root) {
		ext2_msg(sb, KERN_ERR, "error: get root inode failed");
		ret = -ENOMEM;
		goto failed_mount3;
	}
	if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
		ext2_msg(sb, KERN_WARNING,
			"warning: mounting ext3 filesystem as ext2");
	if (ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY))
		sb->s_flags |= MS_RDONLY;
	ext2_write_super(sb);
	return 0;

cantfind_ext2:
	if (!silent)
		ext2_msg(sb, KERN_ERR,
			"error: can't find an ext2 filesystem on dev %s.",
			sb->s_id);
	goto failed_mount;
failed_mount3:
	if (sbi->s_mb_cache)
		ext2_xattr_destroy_cache(sbi->s_mb_cache);
	percpu_counter_destroy(&sbi->s_freeblocks_counter);
	percpu_counter_destroy(&sbi->s_freeinodes_counter);
	percpu_counter_destroy(&sbi->s_dirs_counter);
failed_mount2:
	for (i = 0; i < db_count; i++)
		brelse(sbi->s_group_desc[i]);
failed_mount_group_desc:
	kfree(sbi->s_group_desc);
	kfree(sbi->s_debts);
failed_mount:
	brelse(bh);
failed_sbi:
	sb->s_fs_info = NULL;
	kfree(sbi->s_blockgroup_lock);
	kfree(sbi);
failed:
	return ret;
}

static void ext2_clear_super_error(struct super_block *sb)
{
	struct buffer_head *sbh = EXT2_SB(sb)->s_sbh;

	if (buffer_write_io_error(sbh)) {
		/*
		 * Oh, dear.  A previous attempt to write the
		 * superblock failed.  This could happen because the
		 * USB device was yanked out.  Or it could happen to
		 * be a transient write error and maybe the block will
		 * be remapped.  Nothing we can do but to retry the
		 * write and hope for the best.
		 */
		ext2_msg(sb, KERN_ERR,
		       "previous I/O error to superblock detected\n");
		clear_buffer_write_io_error(sbh);
		set_buffer_uptodate(sbh);
	}
}

static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
			    int wait)
{
	ext2_clear_super_error(sb);
	spin_lock(&EXT2_SB(sb)->s_lock);
	es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
	es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
	es->s_wtime = cpu_to_le32(get_seconds());
	/* unlock before we do IO */
	spin_unlock(&EXT2_SB(sb)->s_lock);
	mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
	if (wait)
		sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
}
Ejemplo n.º 21
0
struct super_block * ext2_read_super (struct super_block * sb, void * data,
				      int silent)
{
	struct buffer_head * bh;
	struct ext2_super_block * es;
	unsigned long sb_block = 1;
	unsigned short resuid = EXT2_DEF_RESUID;
	unsigned short resgid = EXT2_DEF_RESGID;
	unsigned long logic_sb_block = 1;
	kdev_t dev = sb->s_dev;
	int db_count;
	int i, j;

	set_opt (sb->u.ext2_sb.s_mount_opt, CHECK_NORMAL);
	if (!parse_options ((char *) data, &sb_block, &resuid, &resgid,
	    &sb->u.ext2_sb.s_mount_opt)) {
		sb->s_dev = 0;
		return NULL;
	}

	MOD_INC_USE_COUNT;
	lock_super (sb);
	set_blocksize (dev, BLOCK_SIZE);
	if (!(bh = bread (dev, sb_block, BLOCK_SIZE))) {
		sb->s_dev = 0;
		unlock_super (sb);
		printk ("EXT2-fs: unable to read superblock\n");
		MOD_DEC_USE_COUNT;
		return NULL;
	}
	/*
	 * Note: s_es must be initialized s_es as soon as possible because
	 * some ext2 macro-instructions depend on its value
	 */
	es = (struct ext2_super_block *) bh->b_data;
	sb->u.ext2_sb.s_es = es;
	sb->s_magic = es->s_magic;
	if (sb->s_magic != EXT2_SUPER_MAGIC) {
		if (!silent)
			printk ("VFS: Can't find an ext2 filesystem on dev "
				"%s.\n", kdevname(dev));
	failed_mount:
		sb->s_dev = 0;
		unlock_super (sb);
		if (bh)
			brelse(bh);
		MOD_DEC_USE_COUNT;
		return NULL;
	}
	if (es->s_rev_level > EXT2_GOOD_OLD_REV) {
		if (es->s_feature_incompat & ~EXT2_FEATURE_INCOMPAT_SUPP) {
			printk("EXT2-fs: %s: couldn't mount because of "
			       "unsupported optional features.\n", 
			       kdevname(dev));
			goto failed_mount;
		}
		if (!(sb->s_flags & MS_RDONLY) &&
		    (es->s_feature_ro_compat & ~EXT2_FEATURE_RO_COMPAT_SUPP)) {
			printk("EXT2-fs: %s: couldn't mount RDWR because of "
			       "unsupported optional features.\n", 
			       kdevname(dev));
			goto failed_mount;
		}
	}
	sb->s_blocksize_bits = sb->u.ext2_sb.s_es->s_log_block_size + 10;
	sb->s_blocksize = 1 << sb->s_blocksize_bits;
	if (sb->s_blocksize != BLOCK_SIZE && 
	    (sb->s_blocksize == 1024 || sb->s_blocksize == 2048 ||  
	     sb->s_blocksize == 4096)) {
		unsigned long offset;

		brelse (bh);
		set_blocksize (dev, sb->s_blocksize);
		logic_sb_block = (sb_block*BLOCK_SIZE) / sb->s_blocksize;
		offset = (sb_block*BLOCK_SIZE) % sb->s_blocksize;
		bh = bread (dev, logic_sb_block, sb->s_blocksize);
		if(!bh) {
			printk("EXT2-fs: Couldn't read superblock on "
			       "2nd try.\n");
			goto failed_mount;
		}
		es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
		sb->u.ext2_sb.s_es = es;
		if (es->s_magic != EXT2_SUPER_MAGIC) {
			printk ("EXT2-fs: Magic mismatch, very weird !\n");
			goto failed_mount;
		}
	}
	if (es->s_rev_level == EXT2_GOOD_OLD_REV) {
		sb->u.ext2_sb.s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
		sb->u.ext2_sb.s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
	} else {
		sb->u.ext2_sb.s_inode_size = es->s_inode_size;
		sb->u.ext2_sb.s_first_ino = es->s_first_ino;
		if (sb->u.ext2_sb.s_inode_size != EXT2_GOOD_OLD_INODE_SIZE) {
			printk ("EXT2-fs: unsupported inode size: %d\n",
				sb->u.ext2_sb.s_inode_size);
			goto failed_mount;
		}
	}
	sb->u.ext2_sb.s_frag_size = EXT2_MIN_FRAG_SIZE <<
				   es->s_log_frag_size;
	if (sb->u.ext2_sb.s_frag_size)
		sb->u.ext2_sb.s_frags_per_block = sb->s_blocksize /
						  sb->u.ext2_sb.s_frag_size;
	else
		sb->s_magic = 0;
	sb->u.ext2_sb.s_blocks_per_group = es->s_blocks_per_group;
	sb->u.ext2_sb.s_frags_per_group = es->s_frags_per_group;
	sb->u.ext2_sb.s_inodes_per_group = es->s_inodes_per_group;
	sb->u.ext2_sb.s_inodes_per_block = sb->s_blocksize /
					   EXT2_INODE_SIZE(sb);
	sb->u.ext2_sb.s_itb_per_group = sb->u.ext2_sb.s_inodes_per_group /
				        sb->u.ext2_sb.s_inodes_per_block;
	sb->u.ext2_sb.s_desc_per_block = sb->s_blocksize /
					 sizeof (struct ext2_group_desc);
	sb->u.ext2_sb.s_sbh = bh;
	if (resuid != EXT2_DEF_RESUID)
		sb->u.ext2_sb.s_resuid = resuid;
	else
		sb->u.ext2_sb.s_resuid = es->s_def_resuid;
	if (resgid != EXT2_DEF_RESGID)
		sb->u.ext2_sb.s_resgid = resgid;
	else
		sb->u.ext2_sb.s_resgid = es->s_def_resgid;
	sb->u.ext2_sb.s_mount_state = es->s_state;
	sb->u.ext2_sb.s_rename_lock = 0;
	sb->u.ext2_sb.s_rename_wait = NULL;
	sb->u.ext2_sb.s_addr_per_block_bits =
		log2 (EXT2_ADDR_PER_BLOCK(sb));
	sb->u.ext2_sb.s_desc_per_block_bits =
		log2 (EXT2_DESC_PER_BLOCK(sb));
	if (sb->s_magic != EXT2_SUPER_MAGIC) {
		if (!silent)
			printk ("VFS: Can't find an ext2 filesystem on dev "
				"%s.\n",
				kdevname(dev));
		goto failed_mount;
	}
	if (sb->s_blocksize != bh->b_size) {
		if (!silent)
			printk ("VFS: Unsupported blocksize on dev "
				"%s.\n", kdevname(dev));
		goto failed_mount;
	}

	if (sb->s_blocksize != sb->u.ext2_sb.s_frag_size) {
		printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
			sb->u.ext2_sb.s_frag_size, sb->s_blocksize);
		goto failed_mount;
	}

	if (sb->u.ext2_sb.s_blocks_per_group > sb->s_blocksize * 8) {
		printk ("EXT2-fs: #blocks per group too big: %lu\n",
			sb->u.ext2_sb.s_blocks_per_group);
		goto failed_mount;
	}
	if (sb->u.ext2_sb.s_frags_per_group > sb->s_blocksize * 8) {
		printk ("EXT2-fs: #fragments per group too big: %lu\n",
			sb->u.ext2_sb.s_frags_per_group);
		goto failed_mount;
	}
	if (sb->u.ext2_sb.s_inodes_per_group > sb->s_blocksize * 8) {
		printk ("EXT2-fs: #inodes per group too big: %lu\n",
			sb->u.ext2_sb.s_inodes_per_group);
		goto failed_mount;
	}

	sb->u.ext2_sb.s_groups_count = (es->s_blocks_count -
				        es->s_first_data_block +
				       EXT2_BLOCKS_PER_GROUP(sb) - 1) /
				       EXT2_BLOCKS_PER_GROUP(sb);
	db_count = (sb->u.ext2_sb.s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
		   EXT2_DESC_PER_BLOCK(sb);
	sb->u.ext2_sb.s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
	if (sb->u.ext2_sb.s_group_desc == NULL) {
		printk ("EXT2-fs: not enough memory\n");
		goto failed_mount;
	}
	for (i = 0; i < db_count; i++) {
		sb->u.ext2_sb.s_group_desc[i] = bread (dev, logic_sb_block + i + 1,
						       sb->s_blocksize);
		if (!sb->u.ext2_sb.s_group_desc[i]) {
			for (j = 0; j < i; j++)
				brelse (sb->u.ext2_sb.s_group_desc[j]);
			kfree_s (sb->u.ext2_sb.s_group_desc,
				 db_count * sizeof (struct buffer_head *));
			printk ("EXT2-fs: unable to read group descriptors\n");
			goto failed_mount;
		}
	}
	if (!ext2_check_descriptors (sb)) {
		for (j = 0; j < db_count; j++)
			brelse (sb->u.ext2_sb.s_group_desc[j]);
		kfree_s (sb->u.ext2_sb.s_group_desc,
			 db_count * sizeof (struct buffer_head *));
		printk ("EXT2-fs: group descriptors corrupted !\n");
		goto failed_mount;
	}
	for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++) {
		sb->u.ext2_sb.s_inode_bitmap_number[i] = 0;
		sb->u.ext2_sb.s_inode_bitmap[i] = NULL;
		sb->u.ext2_sb.s_block_bitmap_number[i] = 0;
		sb->u.ext2_sb.s_block_bitmap[i] = NULL;
	}
	sb->u.ext2_sb.s_loaded_inode_bitmaps = 0;
	sb->u.ext2_sb.s_loaded_block_bitmaps = 0;
	sb->u.ext2_sb.s_db_per_group = db_count;
	unlock_super (sb);
	/*
	 * set up enough so that it can read an inode
	 */
	sb->s_dev = dev;
	sb->s_op = &ext2_sops;
	if (!(sb->s_mounted = iget (sb, EXT2_ROOT_INO))) {
		sb->s_dev = 0;
		for (i = 0; i < db_count; i++)
			if (sb->u.ext2_sb.s_group_desc[i])
				brelse (sb->u.ext2_sb.s_group_desc[i]);
		kfree_s (sb->u.ext2_sb.s_group_desc,
			 db_count * sizeof (struct buffer_head *));
		brelse (bh);
		printk ("EXT2-fs: get root inode failed\n");
		MOD_DEC_USE_COUNT;
		return NULL;
	}
	ext2_setup_super (sb, es);
	return sb;
}
Ejemplo n.º 22
0
struct super_block * ext2_read_super (struct super_block * sb, void * data,
				      int silent)
{
	struct buffer_head * bh;
	struct ext2_super_block * es;
	unsigned long sb_block = 1;
	unsigned long logic_sb_block = 1;
	int dev = sb->s_dev;
	int bh_count;
	int i, j;
#ifdef EXT2FS_PRE_02B_COMPAT
	int fs_converted = 0;
#endif

	set_opt (sb->u.ext2_sb.s_mount_opt, CHECK_NORMAL);
	if (!parse_options ((char *) data, &sb_block,
	    &sb->u.ext2_sb.s_mount_opt)) {
		sb->s_dev = 0;
		return NULL;
	}

	lock_super (sb);
	set_blocksize (dev, BLOCK_SIZE);
	if (!(bh = bread (dev, sb_block, BLOCK_SIZE))) {
		sb->s_dev = 0;
		unlock_super (sb);
		printk ("EXT2-fs: unable to read superblock\n");
		return NULL;
	}
	/*
	 * Note: s_es must be initialized s_es as soon as possible because
	 * some ext2 macro-instructions depend on its value
	 */
	es = (struct ext2_super_block *) bh->b_data;
	sb->u.ext2_sb.s_es = es;
	sb->s_magic = es->s_magic;
	if (sb->s_magic != EXT2_SUPER_MAGIC
#ifdef EXT2FS_PRE_02B_COMPAT
	   && sb->s_magic != EXT2_PRE_02B_MAGIC
#endif
	   ) {
		sb->s_dev = 0;
		unlock_super (sb);
		brelse (bh);
		if (!silent)
			printk ("VFS: Can't find an ext2 filesystem on dev %d/%d.\n",
				MAJOR(dev), MINOR(dev));
		return NULL;
	}
	sb->s_blocksize = EXT2_MIN_BLOCK_SIZE << es->s_log_block_size;
	sb->s_blocksize_bits = EXT2_BLOCK_SIZE_BITS(sb);
	if (sb->s_blocksize != BLOCK_SIZE && 
	    (sb->s_blocksize == 1024 || sb->s_blocksize == 2048 ||  
	     sb->s_blocksize == 4096)) {
		unsigned long offset;

		brelse (bh);
		set_blocksize (dev, sb->s_blocksize);
		logic_sb_block = sb_block / sb->s_blocksize;
		offset = sb_block % sb->s_blocksize;
		bh = bread (dev, logic_sb_block, sb->s_blocksize);
		if(!bh)
			return NULL;
		es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
		sb->u.ext2_sb.s_es = es;
		if (es->s_magic != EXT2_SUPER_MAGIC) {
			sb->s_dev = 0;
			unlock_super (sb);
			brelse (bh);
			printk ("EXT2-fs: Magic mismatch, very weird !\n");
			return NULL;
		}
	}
	sb->u.ext2_sb.s_frag_size = EXT2_MIN_FRAG_SIZE <<
				   es->s_log_frag_size;
	if (sb->u.ext2_sb.s_frag_size)
		sb->u.ext2_sb.s_frags_per_block = sb->s_blocksize /
						  sb->u.ext2_sb.s_frag_size;
	else
		sb->s_magic = 0;
	sb->u.ext2_sb.s_blocks_per_group = es->s_blocks_per_group;
	sb->u.ext2_sb.s_frags_per_group = es->s_frags_per_group;
	sb->u.ext2_sb.s_inodes_per_group = es->s_inodes_per_group;
	sb->u.ext2_sb.s_inodes_per_block = sb->s_blocksize /
					   sizeof (struct ext2_inode);
	sb->u.ext2_sb.s_itb_per_group = sb->u.ext2_sb.s_inodes_per_group /
				        sb->u.ext2_sb.s_inodes_per_block;
	sb->u.ext2_sb.s_desc_per_block = sb->s_blocksize /
					 sizeof (struct ext2_group_desc);
	sb->u.ext2_sb.s_sbh = bh;
	sb->u.ext2_sb.s_es = es;
	sb->u.ext2_sb.s_mount_state = es->s_state;
	sb->u.ext2_sb.s_rename_lock = 0;
	sb->u.ext2_sb.s_rename_wait = NULL;
#ifdef EXT2FS_PRE_02B_COMPAT
	if (sb->s_magic == EXT2_PRE_02B_MAGIC) {
		if (es->s_blocks_count > 262144) {
			/*
			 * fs > 256 MB can't be converted
			 */ 
			sb->s_dev = 0;
			unlock_super (sb);
			brelse (bh);
			printk ("EXT2-fs: trying to mount a pre-0.2b file"
				"system which cannot be converted\n");
			return NULL;
		}
		printk ("EXT2-fs: mounting a pre 0.2b file system, "
			"will try to convert the structure\n");
		if (!(sb->s_flags & MS_RDONLY)) {
			sb->s_dev = 0;
			unlock_super (sb);
			brelse (bh);
			printk ("EXT2-fs: cannot convert a read-only fs\n");
			return NULL;
		}
		if (!convert_pre_02b_fs (sb, bh)) {
			sb->s_dev = 0;
			unlock_super (sb);
			brelse (bh);
			printk ("EXT2-fs: conversion failed !!!\n");
			return NULL;
		}
		printk ("EXT2-fs: conversion succeeded !!!\n");
		fs_converted = 1;
	}
#endif
	if (sb->s_magic != EXT2_SUPER_MAGIC) {
		sb->s_dev = 0;
		unlock_super (sb);
		brelse (bh);
		if (!silent)
			printk ("VFS: Can't find an ext2 filesystem on dev %d/%d.\n",
				MAJOR(dev), MINOR(dev));
		return NULL;
	}
	if (sb->s_blocksize != bh->b_size) {
		sb->s_dev = 0;
		unlock_super (sb);
		brelse (bh);
		if (!silent)
			printk ("VFS: Unsupported blocksize on dev 0x%04x.\n",
				dev);
		return NULL;
	}

	if (sb->s_blocksize != sb->u.ext2_sb.s_frag_size) {
		sb->s_dev = 0;
		unlock_super (sb);
		brelse (bh);
		printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
			sb->u.ext2_sb.s_frag_size, sb->s_blocksize);
		return NULL;
	}

	sb->u.ext2_sb.s_groups_count = (es->s_blocks_count -
				        es->s_first_data_block +
				       EXT2_BLOCKS_PER_GROUP(sb) - 1) /
				       EXT2_BLOCKS_PER_GROUP(sb);
	for (i = 0; i < EXT2_MAX_GROUP_DESC; i++)
		sb->u.ext2_sb.s_group_desc[i] = NULL;
	bh_count = (sb->u.ext2_sb.s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
		   EXT2_DESC_PER_BLOCK(sb);
	if (bh_count > EXT2_MAX_GROUP_DESC) {
		sb->s_dev = 0;
		unlock_super (sb);
		brelse (bh);
		printk ("EXT2-fs: file system is too big\n");
		return NULL;
	}
	for (i = 0; i < bh_count; i++) {
		sb->u.ext2_sb.s_group_desc[i] = bread (dev, logic_sb_block + i + 1,
						       sb->s_blocksize);
		if (!sb->u.ext2_sb.s_group_desc[i]) {
			sb->s_dev = 0;
			unlock_super (sb);
			for (j = 0; j < i; j++)
				brelse (sb->u.ext2_sb.s_group_desc[j]);
			brelse (bh);
			printk ("EXT2-fs: unable to read group descriptors\n");
			return NULL;
		}
	}
	if (!ext2_check_descriptors (sb)) {
		sb->s_dev = 0;
		unlock_super (sb);
		for (j = 0; j < i; j++)
			brelse (sb->u.ext2_sb.s_group_desc[j]);
		brelse (bh);
		printk ("EXT2-fs: group descriptors corrupted !\n");
		return NULL;
	}
	for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++) {
		sb->u.ext2_sb.s_inode_bitmap_number[i] = 0;
		sb->u.ext2_sb.s_inode_bitmap[i] = NULL;
		sb->u.ext2_sb.s_block_bitmap_number[i] = 0;
		sb->u.ext2_sb.s_block_bitmap[i] = NULL;
	}
	sb->u.ext2_sb.s_loaded_inode_bitmaps = 0;
	sb->u.ext2_sb.s_loaded_block_bitmaps = 0;
	unlock_super (sb);
	/*
	 * set up enough so that it can read an inode
	 */
	sb->s_dev = dev;
	sb->s_op = &ext2_sops;
	if (!(sb->s_mounted = iget (sb, EXT2_ROOT_INO))) {
		sb->s_dev = 0;
		for (i = 0; i < EXT2_MAX_GROUP_DESC; i++)
			if (sb->u.ext2_sb.s_group_desc[i])
				brelse (sb->u.ext2_sb.s_group_desc[i]);
		brelse (bh);
		printk ("EXT2-fs: get root inode failed\n");
		return NULL;
	}
#ifdef EXT2FS_PRE_02B_COMPAT
	if (fs_converted) {
		for (i = 0; i < bh_count; i++)
			sb->u.ext2_sb.s_group_desc[i]->b_dirt = 1;
		sb->s_dirt = 1;
	}
#endif
	ext2_setup_super (sb, es);
	return sb;
}
Ejemplo n.º 23
0
struct super_block * ext2_read_super (struct super_block * sb, void * data,
				      int silent)
{
	struct buffer_head * bh;
  	struct ext2_sb_info * sbi = EXT2_SB(sb);
	struct ext2_super_block * es;
	unsigned long sb_block = 1;
	unsigned short resuid = EXT2_DEF_RESUID;
	unsigned short resgid = EXT2_DEF_RESGID;
	unsigned long block;
	unsigned long logic_sb_block;
	unsigned long offset = 0;
	kdev_t dev = sb->s_dev;
	int blocksize = BLOCK_SIZE;
	int db_count;
	int i, j;

	/*
	 * See what the current blocksize for the device is, and
	 * use that as the blocksize.  Otherwise (or if the blocksize
	 * is smaller than the default) use the default.
	 * This is important for devices that have a hardware
	 * sectorsize that is larger than the default.
	 */
	blocksize = get_hardsect_size(dev);
	if(blocksize < BLOCK_SIZE )
	    blocksize = BLOCK_SIZE;

	sb->u.ext2_sb.s_mount_opt = 0;
	if (!parse_options ((char *) data, &sb_block, &resuid, &resgid,
	    &sb->u.ext2_sb.s_mount_opt)) {
		return NULL;
	}

	if (set_blocksize(dev, blocksize) < 0) {
		printk ("EXT2-fs: unable to set blocksize %d\n", blocksize);
		return NULL;
	}
	sb->s_blocksize = blocksize;

	/*
	 * If the superblock doesn't start on a sector boundary,
	 * calculate the offset.  FIXME(eric) this doesn't make sense
	 * that we would have to do this.
	 */
	if (blocksize != BLOCK_SIZE) {
		logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
		offset = (sb_block*BLOCK_SIZE) % blocksize;
	} else {
		logic_sb_block = sb_block;
	}

	if (!(bh = sb_bread(sb, logic_sb_block))) {
		printk ("EXT2-fs: unable to read superblock\n");
		return NULL;
	}
	/*
	 * Note: s_es must be initialized as soon as possible because
	 *       some ext2 macro-instructions depend on its value
	 */
	es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
	sb->u.ext2_sb.s_es = es;
	sb->s_magic = le16_to_cpu(es->s_magic);
	if (sb->s_magic != EXT2_SUPER_MAGIC) {
		if (!silent)
			printk ("VFS: Can't find ext2 filesystem on dev %s.\n",
				bdevname(dev));
		goto failed_mount;
	}
	if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
	    (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
	     EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
	     EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
		printk("EXT2-fs warning: feature flags set on rev 0 fs, "
		       "running e2fsck is recommended\n");
	/*
	 * Check feature flags regardless of the revision level, since we
	 * previously didn't change the revision level when setting the flags,
	 * so there is a chance incompat flags are set on a rev 0 filesystem.
	 */
	if ((i = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))) {
		printk("EXT2-fs: %s: couldn't mount because of "
		       "unsupported optional features (%x).\n",
		       bdevname(dev), i);
		goto failed_mount;
	}
	if (!(sb->s_flags & MS_RDONLY) &&
	    (i = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
		printk("EXT2-fs: %s: couldn't mount RDWR because of "
		       "unsupported optional features (%x).\n",
		       bdevname(dev), i);
		goto failed_mount;
	}
	if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
		ext2_warning(sb, __FUNCTION__,
			"mounting ext3 filesystem as ext2\n");
	sb->s_blocksize_bits =
		le32_to_cpu(EXT2_SB(sb)->s_es->s_log_block_size) + 10;
	sb->s_blocksize = 1 << sb->s_blocksize_bits;

	sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);

	/* If the blocksize doesn't match, re-read the thing.. */
	if (sb->s_blocksize != blocksize) {
		blocksize = sb->s_blocksize;
		brelse(bh);

		if (set_blocksize(dev, blocksize) < 0) {
			printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
			return NULL;
		}

		logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
		offset = (sb_block*BLOCK_SIZE) % blocksize;
		bh = sb_bread(sb, logic_sb_block);
		if(!bh) {
			printk("EXT2-fs: Couldn't read superblock on "
			       "2nd try.\n");
			goto failed_mount;
		}
		es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
		sb->u.ext2_sb.s_es = es;
		if (es->s_magic != le16_to_cpu(EXT2_SUPER_MAGIC)) {
			printk ("EXT2-fs: Magic mismatch, very weird !\n");
			goto failed_mount;
		}
	}

	if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
		sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
		sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
	} else {
		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
		if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
		    (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
		    (sbi->s_inode_size > blocksize)) {
			printk ("EXT2-fs: unsupported inode size: %d\n",
				sbi->s_inode_size);
			goto failed_mount;
		}
	}
	sb->u.ext2_sb.s_frag_size = EXT2_MIN_FRAG_SIZE <<
				   le32_to_cpu(es->s_log_frag_size);
	if (sb->u.ext2_sb.s_frag_size)
		sb->u.ext2_sb.s_frags_per_block = sb->s_blocksize /
						  sb->u.ext2_sb.s_frag_size;
	else
		sb->s_magic = 0;
	sb->u.ext2_sb.s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
	sb->u.ext2_sb.s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
	sb->u.ext2_sb.s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
	sb->u.ext2_sb.s_inodes_per_block = sb->s_blocksize /
					   EXT2_INODE_SIZE(sb);
	sb->u.ext2_sb.s_itb_per_group = sb->u.ext2_sb.s_inodes_per_group /
				        sb->u.ext2_sb.s_inodes_per_block;
	sb->u.ext2_sb.s_desc_per_block = sb->s_blocksize /
					 sizeof (struct ext2_group_desc);
	sb->u.ext2_sb.s_sbh = bh;
	if (resuid != EXT2_DEF_RESUID)
		sb->u.ext2_sb.s_resuid = resuid;
	else
		sb->u.ext2_sb.s_resuid = le16_to_cpu(es->s_def_resuid);
	if (resgid != EXT2_DEF_RESGID)
		sb->u.ext2_sb.s_resgid = resgid;
	else
		sb->u.ext2_sb.s_resgid = le16_to_cpu(es->s_def_resgid);
	sb->u.ext2_sb.s_mount_state = le16_to_cpu(es->s_state);
	sb->u.ext2_sb.s_addr_per_block_bits =
		log2 (EXT2_ADDR_PER_BLOCK(sb));
	sb->u.ext2_sb.s_desc_per_block_bits =
		log2 (EXT2_DESC_PER_BLOCK(sb));
	if (sb->s_magic != EXT2_SUPER_MAGIC) {
		if (!silent)
			printk ("VFS: Can't find an ext2 filesystem on dev "
				"%s.\n",
				bdevname(dev));
		goto failed_mount;
	}
	if (sb->s_blocksize != bh->b_size) {
		if (!silent)
			printk ("VFS: Unsupported blocksize on dev "
				"%s.\n", bdevname(dev));
		goto failed_mount;
	}

	if (sb->s_blocksize != sb->u.ext2_sb.s_frag_size) {
		printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
			sb->u.ext2_sb.s_frag_size, sb->s_blocksize);
		goto failed_mount;
	}

	if (sb->u.ext2_sb.s_blocks_per_group > sb->s_blocksize * 8) {
		printk ("EXT2-fs: #blocks per group too big: %lu\n",
			sb->u.ext2_sb.s_blocks_per_group);
		goto failed_mount;
	}
	if (sb->u.ext2_sb.s_frags_per_group > sb->s_blocksize * 8) {
		printk ("EXT2-fs: #fragments per group too big: %lu\n",
			sb->u.ext2_sb.s_frags_per_group);
		goto failed_mount;
	}
	if (sb->u.ext2_sb.s_inodes_per_group > sb->s_blocksize * 8) {
		printk ("EXT2-fs: #inodes per group too big: %lu\n",
			sb->u.ext2_sb.s_inodes_per_group);
		goto failed_mount;
	}

	sb->u.ext2_sb.s_groups_count = (le32_to_cpu(es->s_blocks_count) -
				        le32_to_cpu(es->s_first_data_block) +
				       EXT2_BLOCKS_PER_GROUP(sb) - 1) /
				       EXT2_BLOCKS_PER_GROUP(sb);
	db_count = (sb->u.ext2_sb.s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
		   EXT2_DESC_PER_BLOCK(sb);
	sb->u.ext2_sb.s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
	if (sb->u.ext2_sb.s_group_desc == NULL) {
		printk ("EXT2-fs: not enough memory\n");
		goto failed_mount;
	}
	for (i = 0; i < db_count; i++) {
		block = descriptor_loc(sb, logic_sb_block, i);
		sbi->s_group_desc[i] = sb_bread(sb, block);
		if (!sbi->s_group_desc[i]) {
			for (j = 0; j < i; j++)
				brelse (sbi->s_group_desc[j]);
			kfree(sbi->s_group_desc);
			printk ("EXT2-fs: unable to read group descriptors\n");
			goto failed_mount;
		}
	}
	if (!ext2_check_descriptors (sb)) {
		printk ("EXT2-fs: group descriptors corrupted!\n");
		db_count = i;
		goto failed_mount2;
	}
	for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++) {
		sb->u.ext2_sb.s_inode_bitmap_number[i] = 0;
		sb->u.ext2_sb.s_inode_bitmap[i] = NULL;
		sb->u.ext2_sb.s_block_bitmap_number[i] = 0;
		sb->u.ext2_sb.s_block_bitmap[i] = NULL;
	}
	sb->u.ext2_sb.s_loaded_inode_bitmaps = 0;
	sb->u.ext2_sb.s_loaded_block_bitmaps = 0;
	sb->u.ext2_sb.s_gdb_count = db_count;
	/*
	 * set up enough so that it can read an inode
	 */
	sb->s_op = &ext2_sops;
	sb->s_root = d_alloc_root(iget(sb, EXT2_ROOT_INO));
	if (!sb->s_root || !S_ISDIR(sb->s_root->d_inode->i_mode) ||
	    !sb->s_root->d_inode->i_blocks || !sb->s_root->d_inode->i_size) {
		if (sb->s_root) {
			dput(sb->s_root);
			sb->s_root = NULL;
			printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
		} else
			printk(KERN_ERR "EXT2-fs: get root inode failed\n");
		goto failed_mount2;
	}
	ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
	return sb;
failed_mount2:
	for (i = 0; i < db_count; i++)
		brelse(sb->u.ext2_sb.s_group_desc[i]);
	kfree(sb->u.ext2_sb.s_group_desc);
failed_mount:
	brelse(bh);
	return NULL;
}
Ejemplo n.º 24
0
errcode_t online_resize_fs(ext2_filsys fs, const char *mtpt,
			   blk64_t *new_size, int flags EXT2FS_ATTR((unused)))
{
#ifdef __linux__
	struct ext2_new_group_input input;
	struct ext4_new_group_input input64;
	struct ext2_super_block *sb = fs->super;
	unsigned long		new_desc_blocks;
	ext2_filsys 		new_fs;
	errcode_t 		retval;
	double			percent;
	dgrp_t			i;
	blk_t			size;
	int			fd, overhead;
	int			use_old_ioctl = 1;
	int			no_meta_bg_resize = 0;
	int			no_resize_ioctl = 0;

	if (getenv("RESIZE2FS_KERNEL_VERSION")) {
		char *version_to_emulate = getenv("RESIZE2FS_KERNEL_VERSION");
		int kvers = parse_version_number(version_to_emulate);

		if (kvers < VERSION_CODE(3, 7, 0))
			no_meta_bg_resize = 1;
		if (kvers < VERSION_CODE(3, 3, 0))
			no_resize_ioctl = 1;
	}

	if (ext2fs_has_feature_sparse_super2(fs->super) &&
	    (access("/sys/fs/ext4/features/sparse_super2", R_OK) != 0)) {
		com_err(program_name, 0, _("kernel does not support online "
					   "resize with sparse_super2"));
		exit(1);
	}

	printf(_("Filesystem at %s is mounted on %s; "
		 "on-line resizing required\n"), fs->device_name, mtpt);

	if (*new_size < ext2fs_blocks_count(sb)) {
		com_err(program_name, 0, _("On-line shrinking not supported"));
		exit(1);
	}

	/*
	 * If the number of descriptor blocks is going to increase,
	 * the on-line resizing inode must be present.
	 */
	new_desc_blocks = ext2fs_div_ceil(
		ext2fs_div64_ceil(*new_size -
				  fs->super->s_first_data_block,
				  EXT2_BLOCKS_PER_GROUP(fs->super)),
		EXT2_DESC_PER_BLOCK(fs->super));
	printf("old_desc_blocks = %lu, new_desc_blocks = %lu\n",
	       fs->desc_blocks, new_desc_blocks);

	/*
	 * Do error checking to make sure the resize will be successful.
	 */
	if ((access("/sys/fs/ext4/features/meta_bg_resize", R_OK) != 0) ||
	    no_meta_bg_resize) {
		if (!ext2fs_has_feature_resize_inode(fs->super) &&
		    (new_desc_blocks != fs->desc_blocks)) {
			com_err(program_name, 0,
				_("Filesystem does not support online resizing"));
			exit(1);
		}

		if (ext2fs_has_feature_resize_inode(fs->super) &&
		    new_desc_blocks > (fs->desc_blocks +
				       fs->super->s_reserved_gdt_blocks)) {
			com_err(program_name, 0,
				_("Not enough reserved gdt blocks for resizing"));
			exit(1);
		}

		if ((ext2fs_blocks_count(sb) > MAX_32_NUM) ||
		    (*new_size > MAX_32_NUM)) {
			com_err(program_name, 0,
				_("Kernel does not support resizing a file system this large"));
			exit(1);
		}
	}

	fd = open(mtpt, O_RDONLY);
	if (fd < 0) {
		com_err(program_name, errno,
			_("while trying to open mountpoint %s"), mtpt);
		exit(1);
	}

	if (no_resize_ioctl) {
		printf(_("Old resize interface requested.\n"));
	} else if (ioctl(fd, EXT4_IOC_RESIZE_FS, new_size)) {
		/*
		 * If kernel does not support EXT4_IOC_RESIZE_FS, use the
		 * old online resize. Note that the old approach does not
		 * handle >32 bit file systems
		 *
		 * Sigh, if we are running a 32-bit binary on a 64-bit
		 * kernel (which happens all the time on the MIPS
		 * architecture in Debian, but can happen on other CPU
		 * architectures as well) we will get EINVAL returned
		 * when an ioctl doesn't exist, at least up to Linux
		 * 3.1.  See compat_sys_ioctl() in fs/compat_ioctl.c
		 * in the kernel sources.  This is probably a kernel
		 * bug, but work around it here.
		 */
		if ((errno != ENOTTY) && (errno != EINVAL)) {
			if (errno == EPERM)
				com_err(program_name, 0,
				_("Permission denied to resize filesystem"));
			else
				com_err(program_name, errno,
				_("While checking for on-line resizing "
				  "support"));
			exit(1);
		}
	} else {
		close(fd);
		return 0;
	}

	size = ext2fs_blocks_count(sb);

	if (ioctl(fd, EXT2_IOC_GROUP_EXTEND, &size)) {
		if (errno == EPERM)
			com_err(program_name, 0,
				_("Permission denied to resize filesystem"));
		else if (errno == ENOTTY)
			com_err(program_name, 0,
			_("Kernel does not support online resizing"));
		else
			com_err(program_name, errno,
			_("While checking for on-line resizing support"));
		exit(1);
	}

	percent = (ext2fs_r_blocks_count(sb) * 100.0) /
		ext2fs_blocks_count(sb);

	retval = ext2fs_read_bitmaps(fs);
	if (retval) {
		close(fd);
		return retval;
	}

	retval = ext2fs_dup_handle(fs, &new_fs);
	if (retval) {
		close(fd);
		return retval;
	}

	/* The current method of adding one block group at a time to a
	 * mounted filesystem means it is impossible to accommodate the
	 * flex_bg allocation method of placing the metadata together
	 * in a single block group.  For now we "fix" this issue by
	 * using the traditional layout for new block groups, where
	 * each block group is self-contained and contains its own
	 * bitmap blocks and inode tables.  This means we don't get
	 * the layout advantages of flex_bg in the new block groups,
	 * but at least it allows on-line resizing to function.
	 */
	ext2fs_clear_feature_flex_bg(new_fs->super);
	retval = adjust_fs_info(new_fs, fs, 0, *new_size);
	if (retval) {
		close(fd);
		return retval;
	}

	printf(_("Performing an on-line resize of %s to %llu (%dk) blocks.\n"),
	       fs->device_name, *new_size, fs->blocksize / 1024);

	size = fs->group_desc_count * sb->s_blocks_per_group +
		sb->s_first_data_block;
	if (size > *new_size)
		size = *new_size;

	if (ioctl(fd, EXT2_IOC_GROUP_EXTEND, &size)) {
		com_err(program_name, errno,
			_("While trying to extend the last group"));
		exit(1);
	}

	for (i = fs->group_desc_count;
	     i < new_fs->group_desc_count; i++) {

		overhead = (int) (2 + new_fs->inode_blocks_per_group);

		if (ext2fs_bg_has_super(new_fs, new_fs->group_desc_count - 1))
			overhead += 1 + new_fs->desc_blocks +
				new_fs->super->s_reserved_gdt_blocks;

		input.group = i;
		input.block_bitmap = ext2fs_block_bitmap_loc(new_fs, i);
		input.inode_bitmap = ext2fs_inode_bitmap_loc(new_fs, i);
		input.inode_table = ext2fs_inode_table_loc(new_fs, i);
		input.blocks_count = ext2fs_group_blocks_count(new_fs, i);
		input.reserved_blocks = (blk_t) (percent * input.blocks_count
						 / 100.0);

#if 0
		printf("new block bitmap is at 0x%04x\n", input.block_bitmap);
		printf("new inode bitmap is at 0x%04x\n", input.inode_bitmap);
		printf("new inode table is at 0x%04x-0x%04x\n",
		       input.inode_table,
		       input.inode_table + new_fs->inode_blocks_per_group-1);
		printf("new group has %u blocks\n", input.blocks_count);
		printf("new group will reserve %d blocks\n",
		       input.reserved_blocks);
		printf("new group has %d free blocks\n",
		       ext2fs_bg_free_blocks_count(new_fs, i),
		printf("new group has %d free inodes (%d blocks)\n",
		       ext2fs_bg_free_inodes_count(new_fs, i),
		       new_fs->inode_blocks_per_group);
		printf("Adding group #%d\n", input.group);
#endif

		if (use_old_ioctl &&
		    ioctl(fd, EXT2_IOC_GROUP_ADD, &input) == 0)
			continue;
		else
			use_old_ioctl = 0;

		input64.group = input.group;
		input64.block_bitmap = input.block_bitmap;
		input64.inode_bitmap = input.inode_bitmap;
		input64.inode_table = input.inode_table;
		input64.blocks_count = input.blocks_count;
		input64.reserved_blocks = input.reserved_blocks;
		input64.unused = input.unused;

		if (ioctl(fd, EXT4_IOC_GROUP_ADD, &input64) < 0) {
			com_err(program_name, errno,
				_("While trying to add group #%d"),
				input.group);
			exit(1);
		}
	}

	ext2fs_free(new_fs);
	close(fd);

	return 0;
#else
	printf(_("Filesystem at %s is mounted on %s, and on-line resizing is "
		 "not supported on this system.\n"), fs->device_name, mtpt);
	exit(1);
#endif
}
Ejemplo n.º 25
0
/*
 *  Note: if superblock is non-zero, block-size must also be non-zero.
 * 	Superblock and block_size can be zero to use the default size.
 *
 * Valid flags for ext2fs_open()
 *
 * 	EXT2_FLAG_RW	- Open the filesystem for read/write.
 * 	EXT2_FLAG_FORCE - Open the filesystem even if some of the
 *				features aren't supported.
 *	EXT2_FLAG_JOURNAL_DEV_OK - Open an ext3 journal device
 *	EXT2_FLAG_SKIP_MMP - Open without multi-mount protection check.
 *	EXT2_FLAG_64BITS - Allow 64-bit bitfields (needed for large
 *				filesystems)
 */
errcode_t ext2fs_open2(const char *name, const char *io_options,
		       int flags, int superblock,
		       unsigned int block_size, io_manager manager,
		       ext2_filsys *ret_fs)
{
	ext2_filsys	fs;
	errcode_t	retval;
	unsigned long	i, first_meta_bg;
	__u32		features;
	unsigned int	blocks_per_group, io_flags;
	blk64_t		group_block, blk;
	char		*dest, *cp;
	int		group_zero_adjust = 0;
#ifdef WORDS_BIGENDIAN
	unsigned int	groups_per_block;
	struct ext2_group_desc *gdp;
	int		j;
#endif
	char		*time_env;

	EXT2_CHECK_MAGIC(manager, EXT2_ET_MAGIC_IO_MANAGER);

	retval = ext2fs_get_mem(sizeof(struct struct_ext2_filsys), &fs);
	if (retval)
		return retval;

	memset(fs, 0, sizeof(struct struct_ext2_filsys));
	fs->magic = EXT2_ET_MAGIC_EXT2FS_FILSYS;
	fs->flags = flags;
	/* don't overwrite sb backups unless flag is explicitly cleared */
	fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
	fs->umask = 022;

	time_env = getenv("E2FSPROGS_FAKE_TIME");
	if (time_env)
		fs->now = strtoul(time_env, NULL, 0);

	retval = ext2fs_get_mem(strlen(name)+1, &fs->device_name);
	if (retval)
		goto cleanup;
	strcpy(fs->device_name, name);
	cp = strchr(fs->device_name, '?');
	if (!io_options && cp) {
		*cp++ = 0;
		io_options = cp;
	}

	io_flags = 0;
	if (flags & EXT2_FLAG_RW)
		io_flags |= IO_FLAG_RW;
	if (flags & EXT2_FLAG_EXCLUSIVE)
		io_flags |= IO_FLAG_EXCLUSIVE;
	if (flags & EXT2_FLAG_DIRECT_IO)
		io_flags |= IO_FLAG_DIRECT_IO;
	retval = manager->open(fs->device_name, io_flags, &fs->io);
	if (retval)
		goto cleanup;
	if (io_options &&
	    (retval = io_channel_set_options(fs->io, io_options)))
		goto cleanup;
	fs->image_io = fs->io;
	fs->io->app_data = fs;
	retval = io_channel_alloc_buf(fs->io, -SUPERBLOCK_SIZE, &fs->super);
	if (retval)
		goto cleanup;
	if (flags & EXT2_FLAG_IMAGE_FILE) {
		retval = ext2fs_get_mem(sizeof(struct ext2_image_hdr),
					&fs->image_header);
		if (retval)
			goto cleanup;
		retval = io_channel_read_blk(fs->io, 0,
					     -(int)sizeof(struct ext2_image_hdr),
					     fs->image_header);
		if (retval)
			goto cleanup;
		if (fs->image_header->magic_number != EXT2_ET_MAGIC_E2IMAGE)
			return EXT2_ET_MAGIC_E2IMAGE;
		superblock = 1;
		block_size = fs->image_header->fs_blocksize;
	}

	/*
	 * If the user specifies a specific block # for the
	 * superblock, then he/she must also specify the block size!
	 * Otherwise, read the master superblock located at offset
	 * SUPERBLOCK_OFFSET from the start of the partition.
	 *
	 * Note: we only save a backup copy of the superblock if we
	 * are reading the superblock from the primary superblock location.
	 */
	if (superblock) {
		if (!block_size) {
			retval = EXT2_ET_INVALID_ARGUMENT;
			goto cleanup;
		}
		io_channel_set_blksize(fs->io, block_size);
		group_block = superblock;
		fs->orig_super = 0;
	} else {
		io_channel_set_blksize(fs->io, SUPERBLOCK_OFFSET);
		superblock = 1;
		group_block = 0;
		retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &fs->orig_super);
		if (retval)
			goto cleanup;
	}
	retval = io_channel_read_blk(fs->io, superblock, -SUPERBLOCK_SIZE,
				     fs->super);
	if (retval)
		goto cleanup;
	if (fs->orig_super)
		memcpy(fs->orig_super, fs->super, SUPERBLOCK_SIZE);

	if (!(fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS)) {
		retval = 0;
		if (!ext2fs_verify_csum_type(fs, fs->super))
			retval = EXT2_ET_UNKNOWN_CSUM;
		if (!ext2fs_superblock_csum_verify(fs, fs->super))
			retval = EXT2_ET_SB_CSUM_INVALID;
	}

#ifdef WORDS_BIGENDIAN
	fs->flags |= EXT2_FLAG_SWAP_BYTES;
	ext2fs_swap_super(fs->super);
#else
	if (fs->flags & EXT2_FLAG_SWAP_BYTES) {
		retval = EXT2_ET_UNIMPLEMENTED;
		goto cleanup;
	}
#endif

	if (fs->super->s_magic != EXT2_SUPER_MAGIC)
		retval = EXT2_ET_BAD_MAGIC;
	if (retval)
		goto cleanup;

	if (fs->super->s_rev_level > EXT2_LIB_CURRENT_REV) {
		retval = EXT2_ET_REV_TOO_HIGH;
		goto cleanup;
	}

	/*
	 * Check for feature set incompatibility
	 */
	if (!(flags & EXT2_FLAG_FORCE)) {
		features = fs->super->s_feature_incompat;
#ifdef EXT2_LIB_SOFTSUPP_INCOMPAT
		if (flags & EXT2_FLAG_SOFTSUPP_FEATURES)
			features &= ~EXT2_LIB_SOFTSUPP_INCOMPAT;
#endif
		if (features & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP) {
			retval = EXT2_ET_UNSUPP_FEATURE;
			goto cleanup;
		}

		features = fs->super->s_feature_ro_compat;
#ifdef EXT2_LIB_SOFTSUPP_RO_COMPAT
		if (flags & EXT2_FLAG_SOFTSUPP_FEATURES)
			features &= ~EXT2_LIB_SOFTSUPP_RO_COMPAT;
#endif
		if ((flags & EXT2_FLAG_RW) &&
		    (features & ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP)) {
			retval = EXT2_ET_RO_UNSUPP_FEATURE;
			goto cleanup;
		}

		if (!(flags & EXT2_FLAG_JOURNAL_DEV_OK) &&
		    ext2fs_has_feature_journal_dev(fs->super)) {
			retval = EXT2_ET_UNSUPP_FEATURE;
			goto cleanup;
		}
	}

	if ((fs->super->s_log_block_size + EXT2_MIN_BLOCK_LOG_SIZE) >
	    EXT2_MAX_BLOCK_LOG_SIZE) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}

	/*
	 * bigalloc requires cluster-aware bitfield operations, which at the
	 * moment means we need EXT2_FLAG_64BITS.
	 */
	if (ext2fs_has_feature_bigalloc(fs->super) &&
	    !(flags & EXT2_FLAG_64BITS)) {
		retval = EXT2_ET_CANT_USE_LEGACY_BITMAPS;
		goto cleanup;
	}

	if (!ext2fs_has_feature_bigalloc(fs->super) &&
	    (fs->super->s_log_block_size != fs->super->s_log_cluster_size)) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->fragsize = fs->blocksize = EXT2_BLOCK_SIZE(fs->super);
	if (EXT2_INODE_SIZE(fs->super) < EXT2_GOOD_OLD_INODE_SIZE) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}

	/* Enforce the block group descriptor size */
	if (ext2fs_has_feature_64bit(fs->super)) {
		if (fs->super->s_desc_size < EXT2_MIN_DESC_SIZE_64BIT) {
			retval = EXT2_ET_BAD_DESC_SIZE;
			goto cleanup;
		}
	} else {
		if (fs->super->s_desc_size &&
		    fs->super->s_desc_size != EXT2_MIN_DESC_SIZE) {
			retval = EXT2_ET_BAD_DESC_SIZE;
			goto cleanup;
		}
	}

	fs->cluster_ratio_bits = fs->super->s_log_cluster_size -
		fs->super->s_log_block_size;
	if (EXT2_BLOCKS_PER_GROUP(fs->super) !=
	    EXT2_CLUSTERS_PER_GROUP(fs->super) << fs->cluster_ratio_bits) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->inode_blocks_per_group = ((EXT2_INODES_PER_GROUP(fs->super) *
				       EXT2_INODE_SIZE(fs->super) +
				       EXT2_BLOCK_SIZE(fs->super) - 1) /
				      EXT2_BLOCK_SIZE(fs->super));
	if (block_size) {
		if (block_size != fs->blocksize) {
			retval = EXT2_ET_UNEXPECTED_BLOCK_SIZE;
			goto cleanup;
		}
	}
	/*
	 * Set the blocksize to the filesystem's blocksize.
	 */
	io_channel_set_blksize(fs->io, fs->blocksize);

	/*
	 * If this is an external journal device, don't try to read
	 * the group descriptors, because they're not there.
	 */
	if (ext2fs_has_feature_journal_dev(fs->super)) {
		fs->group_desc_count = 0;
		*ret_fs = fs;
		return 0;
	}

	if (EXT2_INODES_PER_GROUP(fs->super) == 0) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	/* Precompute the FS UUID to seed other checksums */
	ext2fs_init_csum_seed(fs);

	/*
	 * Read group descriptors
	 */
	blocks_per_group = EXT2_BLOCKS_PER_GROUP(fs->super);
	if (blocks_per_group == 0 ||
	    blocks_per_group > EXT2_MAX_BLOCKS_PER_GROUP(fs->super) ||
	    fs->inode_blocks_per_group > EXT2_MAX_INODES_PER_GROUP(fs->super) ||
           EXT2_DESC_PER_BLOCK(fs->super) == 0 ||
           fs->super->s_first_data_block >= ext2fs_blocks_count(fs->super)) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
						 fs->super->s_first_data_block,
						 blocks_per_group);
	if (fs->group_desc_count * EXT2_INODES_PER_GROUP(fs->super) !=
	    fs->super->s_inodes_count) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
					  EXT2_DESC_PER_BLOCK(fs->super));
	retval = ext2fs_get_array(fs->desc_blocks, fs->blocksize,
				&fs->group_desc);
	if (retval)
		goto cleanup;
	if (!group_block)
		group_block = fs->super->s_first_data_block;
	/*
	 * On a FS with a 1K blocksize, block 0 is reserved for bootloaders
	 * so we must increment block numbers to any group 0 items.
	 *
	 * However, we cannot touch group_block directly because in the meta_bg
	 * case, the ext2fs_descriptor_block_loc2() function will interpret
	 * group_block != s_first_data_block to mean that we want to access the
	 * backup group descriptors.  This is not what we want if the caller
	 * set superblock == 0 (i.e. auto-detect the superblock), which is
	 * what's going on here.
	 */
	if (group_block == 0 && fs->blocksize == 1024)
		group_zero_adjust = 1;
	dest = (char *) fs->group_desc;
#ifdef WORDS_BIGENDIAN
	groups_per_block = EXT2_DESC_PER_BLOCK(fs->super);
#endif
	if (ext2fs_has_feature_meta_bg(fs->super)) {
		first_meta_bg = fs->super->s_first_meta_bg;
		if (first_meta_bg > fs->desc_blocks)
			first_meta_bg = fs->desc_blocks;
	} else
		first_meta_bg = fs->desc_blocks;
	if (first_meta_bg) {
		retval = io_channel_read_blk(fs->io, group_block +
					     group_zero_adjust + 1,
					     first_meta_bg, dest);
		if (retval)
			goto cleanup;
#ifdef WORDS_BIGENDIAN
		gdp = (struct ext2_group_desc *) dest;
		for (j=0; j < groups_per_block*first_meta_bg; j++) {
			gdp = ext2fs_group_desc(fs, fs->group_desc, j);
			ext2fs_swap_group_desc2(fs, gdp);
		}
#endif
		dest += fs->blocksize*first_meta_bg;
	}
	for (i=first_meta_bg ; i < fs->desc_blocks; i++) {
		blk = ext2fs_descriptor_block_loc2(fs, group_block, i);
		retval = io_channel_read_blk64(fs->io, blk, 1, dest);
		if (retval)
			goto cleanup;
#ifdef WORDS_BIGENDIAN
		for (j=0; j < groups_per_block; j++) {
			gdp = ext2fs_group_desc(fs, fs->group_desc,
						i * groups_per_block + j);
			ext2fs_swap_group_desc2(fs, gdp);
		}
#endif
		dest += fs->blocksize;
	}

	fs->stride = fs->super->s_raid_stride;

	/*
	 * If recovery is from backup superblock, Clear _UNININT flags &
	 * reset bg_itable_unused to zero
	 */
	if (superblock > 1 && ext2fs_has_group_desc_csum(fs)) {
		dgrp_t group;

		for (group = 0; group < fs->group_desc_count; group++) {
			ext2fs_bg_flags_clear(fs, group, EXT2_BG_BLOCK_UNINIT);
			ext2fs_bg_flags_clear(fs, group, EXT2_BG_INODE_UNINIT);
			ext2fs_bg_itable_unused_set(fs, group, 0);
			/* The checksum will be reset later, but fix it here
			 * anyway to avoid printing a lot of spurious errors. */
			ext2fs_group_desc_csum_set(fs, group);
		}
		if (fs->flags & EXT2_FLAG_RW)
			ext2fs_mark_super_dirty(fs);
	}

	if (ext2fs_has_feature_mmp(fs->super) &&
	    !(flags & EXT2_FLAG_SKIP_MMP) &&
	    (flags & (EXT2_FLAG_RW | EXT2_FLAG_EXCLUSIVE))) {
		retval = ext2fs_mmp_start(fs);
		if (retval) {
			fs->flags |= EXT2_FLAG_SKIP_MMP; /* just do cleanup */
			ext2fs_mmp_stop(fs);
			goto cleanup;
		}
	}

	if (fs->flags & EXT2_FLAG_SHARE_DUP) {
		fs->block_sha_map = ext2fs_hashmap_create(ext2fs_djb2_hash,
					block_sha_map_free_entry, 4096);
		if (!fs->block_sha_map) {
			retval = EXT2_ET_NO_MEMORY;
			goto cleanup;
		}
		ext2fs_set_feature_shared_blocks(fs->super);
	}

	fs->flags &= ~EXT2_FLAG_NOFREE_ON_ERROR;
	*ret_fs = fs;

	return 0;
cleanup:
	if (!(flags & EXT2_FLAG_NOFREE_ON_ERROR)) {
		ext2fs_free(fs);
		fs = NULL;
	}
	*ret_fs = fs;
	return retval;
}
Ejemplo n.º 26
0
/*
 *  Note: if superblock is non-zero, block-size must also be non-zero.
 * 	Superblock and block_size can be zero to use the default size.
 *
 * Valid flags for ext2fs_open()
 *
 * 	EXT2_FLAG_RW	- Open the filesystem for read/write.
 * 	EXT2_FLAG_FORCE - Open the filesystem even if some of the
 *				features aren't supported.
 *	EXT2_FLAG_JOURNAL_DEV_OK - Open an ext3 journal device
 */
errcode_t ext2fs_open2(const char *name, const char *io_options,
		       int flags, int superblock,
		       unsigned int block_size, io_manager manager,
		       ext2_filsys *ret_fs)
{
	ext2_filsys	fs;
	errcode_t	retval;
	unsigned long	i, first_meta_bg;
	__u32		features;
	int		groups_per_block, blocks_per_group, io_flags;
	blk_t		group_block, blk;
	char		*dest, *cp;
#ifdef WORDS_BIGENDIAN
	struct ext2_group_desc *gdp;
	int		j;
#endif

	EXT2_CHECK_MAGIC(manager, EXT2_ET_MAGIC_IO_MANAGER);

	retval = ext2fs_get_mem(sizeof(struct struct_ext2_filsys), &fs);
	if (retval)
		return retval;

	memset(fs, 0, sizeof(struct struct_ext2_filsys));
	fs->magic = EXT2_ET_MAGIC_EXT2FS_FILSYS;
	fs->flags = flags;
	/* don't overwrite sb backups unless flag is explicitly cleared */
	fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
	fs->umask = 022;
	retval = ext2fs_get_mem(strlen(name)+1, &fs->device_name);
	if (retval)
		goto cleanup;
	strcpy(fs->device_name, name);
	cp = strchr(fs->device_name, '?');
	if (!io_options && cp) {
		*cp++ = 0;
		io_options = cp;
	}

	io_flags = 0;
	if (flags & EXT2_FLAG_RW)
		io_flags |= IO_FLAG_RW;
	if (flags & EXT2_FLAG_EXCLUSIVE)
		io_flags |= IO_FLAG_EXCLUSIVE;
	if (flags & EXT2_FLAG_DIRECT_IO)
		io_flags |= IO_FLAG_DIRECT_IO;
	retval = manager->open(fs->device_name, io_flags, &fs->io);
	if (retval)
		goto cleanup;
	if (io_options &&
	    (retval = io_channel_set_options(fs->io, io_options)))
		goto cleanup;
	fs->image_io = fs->io;
	fs->io->app_data = fs;
	retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &fs->super);
	if (retval)
		goto cleanup;
	if (flags & EXT2_FLAG_IMAGE_FILE) {
		retval = ext2fs_get_mem(sizeof(struct ext2_image_hdr),
					&fs->image_header);
		if (retval)
			goto cleanup;
		retval = io_channel_read_blk(fs->io, 0,
					     -(int)sizeof(struct ext2_image_hdr),
					     fs->image_header);
		if (retval)
			goto cleanup;
		if (fs->image_header->magic_number != EXT2_ET_MAGIC_E2IMAGE)
			return EXT2_ET_MAGIC_E2IMAGE;
		superblock = 1;
		block_size = fs->image_header->fs_blocksize;
	}

	/*
	 * If the user specifies a specific block # for the
	 * superblock, then he/she must also specify the block size!
	 * Otherwise, read the master superblock located at offset
	 * SUPERBLOCK_OFFSET from the start of the partition.
	 *
	 * Note: we only save a backup copy of the superblock if we
	 * are reading the superblock from the primary superblock location.
	 */
	if (superblock) {
		if (!block_size) {
			retval = EXT2_ET_INVALID_ARGUMENT;
			goto cleanup;
		}
		io_channel_set_blksize(fs->io, block_size);
		group_block = superblock;
		fs->orig_super = 0;
	} else {
		io_channel_set_blksize(fs->io, SUPERBLOCK_OFFSET);
		superblock = 1;
		group_block = 0;
		retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &fs->orig_super);
		if (retval)
			goto cleanup;
	}
	retval = io_channel_read_blk(fs->io, superblock, -SUPERBLOCK_SIZE,
				     fs->super);
	if (retval)
		goto cleanup;
	if (fs->orig_super)
		memcpy(fs->orig_super, fs->super, SUPERBLOCK_SIZE);

#ifdef WORDS_BIGENDIAN
	fs->flags |= EXT2_FLAG_SWAP_BYTES;
	ext2fs_swap_super(fs->super);
#else
	if (fs->flags & EXT2_FLAG_SWAP_BYTES) {
		retval = EXT2_ET_UNIMPLEMENTED;
		goto cleanup;
	}
#endif

	if (fs->super->s_magic != EXT2_SUPER_MAGIC) {
		retval = EXT2_ET_BAD_MAGIC;
		goto cleanup;
	}
	if (fs->super->s_rev_level > EXT2_LIB_CURRENT_REV) {
		retval = EXT2_ET_REV_TOO_HIGH;
		goto cleanup;
	}

	/*
	 * Check for feature set incompatibility
	 */
	if (!(flags & EXT2_FLAG_FORCE)) {
		features = fs->super->s_feature_incompat;
#ifdef EXT2_LIB_SOFTSUPP_INCOMPAT
		if (flags & EXT2_FLAG_SOFTSUPP_FEATURES)
			features &= !EXT2_LIB_SOFTSUPP_INCOMPAT;
#endif
		if (features & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP) {
			retval = EXT2_ET_UNSUPP_FEATURE;
			goto cleanup;
		}

		features = fs->super->s_feature_ro_compat;
#ifdef EXT2_LIB_SOFTSUPP_RO_COMPAT
		if (flags & EXT2_FLAG_SOFTSUPP_FEATURES)
			features &= !EXT2_LIB_SOFTSUPP_RO_COMPAT;
#endif
		if ((flags & EXT2_FLAG_RW) &&
		    (features & ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP)) {
			retval = EXT2_ET_RO_UNSUPP_FEATURE;
			goto cleanup;
		}

		if (!(flags & EXT2_FLAG_JOURNAL_DEV_OK) &&
		    (fs->super->s_feature_incompat &
		     EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)) {
			retval = EXT2_ET_UNSUPP_FEATURE;
			goto cleanup;
		}
	}

	if ((fs->super->s_log_block_size + EXT2_MIN_BLOCK_LOG_SIZE) >
	    EXT2_MAX_BLOCK_LOG_SIZE) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->blocksize = EXT2_BLOCK_SIZE(fs->super);
	if (EXT2_INODE_SIZE(fs->super) < EXT2_GOOD_OLD_INODE_SIZE) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->fragsize = EXT2_FRAG_SIZE(fs->super);
	fs->inode_blocks_per_group = ((EXT2_INODES_PER_GROUP(fs->super) *
				       EXT2_INODE_SIZE(fs->super) +
				       EXT2_BLOCK_SIZE(fs->super) - 1) /
				      EXT2_BLOCK_SIZE(fs->super));
	if (block_size) {
		if (block_size != fs->blocksize) {
			retval = EXT2_ET_UNEXPECTED_BLOCK_SIZE;
			goto cleanup;
		}
	}
	/*
	 * Set the blocksize to the filesystem's blocksize.
	 */
	io_channel_set_blksize(fs->io, fs->blocksize);

	/*
	 * If this is an external journal device, don't try to read
	 * the group descriptors, because they're not there.
	 */
	if (fs->super->s_feature_incompat &
	    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) {
		fs->group_desc_count = 0;
		*ret_fs = fs;
		return 0;
	}

	if (EXT2_INODES_PER_GROUP(fs->super) == 0) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}

	/*
	 * Read group descriptors
	 */
	blocks_per_group = EXT2_BLOCKS_PER_GROUP(fs->super);
	if (blocks_per_group == 0 ||
	    blocks_per_group > EXT2_MAX_BLOCKS_PER_GROUP(fs->super) ||
	    fs->inode_blocks_per_group > EXT2_MAX_INODES_PER_GROUP(fs->super) ||
           EXT2_DESC_PER_BLOCK(fs->super) == 0 ||
           fs->super->s_first_data_block >= fs->super->s_blocks_count) {
		retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
	}
	fs->group_desc_count = ext2fs_div_ceil(fs->super->s_blocks_count -
					       fs->super->s_first_data_block,
					       blocks_per_group);
       if (fs->group_desc_count * EXT2_INODES_PER_GROUP(fs->super) !=
           fs->super->s_inodes_count) {
               retval = EXT2_ET_CORRUPT_SUPERBLOCK;
		goto cleanup;
       }
	fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
					  EXT2_DESC_PER_BLOCK(fs->super));
	retval = ext2fs_get_array(fs->desc_blocks, fs->blocksize,
				&fs->group_desc);
	if (retval)
		goto cleanup;
	if (!group_block)
		group_block = fs->super->s_first_data_block;
	dest = (char *) fs->group_desc;
	groups_per_block = EXT2_DESC_PER_BLOCK(fs->super);
	if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
		first_meta_bg = fs->super->s_first_meta_bg;
	else
		first_meta_bg = fs->desc_blocks;
	if (first_meta_bg) {
		retval = io_channel_read_blk(fs->io, group_block+1,
					     first_meta_bg, dest);
		if (retval)
			goto cleanup;
#ifdef WORDS_BIGENDIAN
		gdp = (struct ext2_group_desc *) dest;
		for (j=0; j < groups_per_block*first_meta_bg; j++)
			ext2fs_swap_group_desc(gdp++);
#endif
		dest += fs->blocksize*first_meta_bg;
	}
	for (i=first_meta_bg ; i < fs->desc_blocks; i++) {
		blk = ext2fs_descriptor_block_loc(fs, group_block, i);
		retval = io_channel_read_blk(fs->io, blk, 1, dest);
		if (retval)
			goto cleanup;
#ifdef WORDS_BIGENDIAN
		gdp = (struct ext2_group_desc *) dest;
		for (j=0; j < groups_per_block; j++)
			ext2fs_swap_group_desc(gdp++);
#endif
		dest += fs->blocksize;
	}

	fs->stride = fs->super->s_raid_stride;

	/*
	 * If recovery is from backup superblock, Clear _UNININT flags &
	 * reset bg_itable_unused to zero
	 */
	if (superblock > 1 && EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
					EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
		struct ext2_group_desc *gd;
		for (i = 0, gd = fs->group_desc; i < fs->group_desc_count;
		     i++, gd++) {
			gd->bg_flags &= ~EXT2_BG_BLOCK_UNINIT;
			gd->bg_flags &= ~EXT2_BG_INODE_UNINIT;
			gd->bg_itable_unused = 0;
		}
		ext2fs_mark_super_dirty(fs);
	}

	fs->flags &= ~EXT2_FLAG_NOFREE_ON_ERROR;
	*ret_fs = fs;
	return 0;
cleanup:
	if (flags & EXT2_FLAG_NOFREE_ON_ERROR)
		*ret_fs = fs;
	else
		ext2fs_free(fs);
	return retval;
}
Ejemplo n.º 27
0
errcode_t ext2fs_initialize(const char *name, int flags,
                            struct ext2_super_block *param,
                            io_manager manager, ext2_filsys *ret_fs)
{
    ext2_filsys	fs;
    errcode_t	retval;
    struct ext2_super_block *super;
    int		frags_per_block;
    unsigned int	rem;
    unsigned int	overhead = 0;
    unsigned int	ipg;
    dgrp_t		i;
    blk_t		numblocks;
    int		rsv_gdt;
    int		io_flags;
    char		*buf;
    char		c;

    if (!param || !param->s_blocks_count)
        return EXT2_ET_INVALID_ARGUMENT;

    retval = ext2fs_get_mem(sizeof(struct struct_ext2_filsys), &fs);
    if (retval)
        return retval;

    memset(fs, 0, sizeof(struct struct_ext2_filsys));
    fs->magic = EXT2_ET_MAGIC_EXT2FS_FILSYS;
    fs->flags = flags | EXT2_FLAG_RW;
    fs->umask = 022;
#ifdef WORDS_BIGENDIAN
    fs->flags |= EXT2_FLAG_SWAP_BYTES;
#endif
    io_flags = IO_FLAG_RW;
    if (flags & EXT2_FLAG_EXCLUSIVE)
        io_flags |= IO_FLAG_EXCLUSIVE;
    retval = manager->open(name, io_flags, &fs->io);
    if (retval)
        goto cleanup;
    fs->image_io = fs->io;
    fs->io->app_data = fs;
    retval = ext2fs_get_mem(strlen(name)+1, &fs->device_name);
    if (retval)
        goto cleanup;

    strcpy(fs->device_name, name);
    retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &super);
    if (retval)
        goto cleanup;
    fs->super = super;

    memset(super, 0, SUPERBLOCK_SIZE);

#define set_field(field, default) (super->field = param->field ? \
				   param->field : (default))

    super->s_magic = EXT2_SUPER_MAGIC;
    super->s_state = EXT2_VALID_FS;

    set_field(s_log_block_size, 0);	/* default blocksize: 1024 bytes */
    set_field(s_log_frag_size, 0); /* default fragsize: 1024 bytes */
    set_field(s_first_data_block, super->s_log_block_size ? 0 : 1);
    set_field(s_max_mnt_count, EXT2_DFL_MAX_MNT_COUNT);
    set_field(s_errors, EXT2_ERRORS_DEFAULT);
    set_field(s_feature_compat, 0);
    set_field(s_feature_incompat, 0);
    set_field(s_feature_ro_compat, 0);
    set_field(s_first_meta_bg, 0);
    if (super->s_feature_incompat & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP) {
        retval = EXT2_ET_UNSUPP_FEATURE;
        goto cleanup;
    }
    if (super->s_feature_ro_compat & ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP) {
        retval = EXT2_ET_RO_UNSUPP_FEATURE;
        goto cleanup;
    }

    set_field(s_rev_level, EXT2_GOOD_OLD_REV);
    if (super->s_rev_level >= EXT2_DYNAMIC_REV) {
        set_field(s_first_ino, EXT2_GOOD_OLD_FIRST_INO);
        set_field(s_inode_size, EXT2_GOOD_OLD_INODE_SIZE);
    }

    set_field(s_checkinterval, EXT2_DFL_CHECKINTERVAL);
    super->s_mkfs_time = super->s_lastcheck = fs->now ? fs->now : time(NULL);

    super->s_creator_os = CREATOR_OS;

    fs->blocksize = EXT2_BLOCK_SIZE(super);
    fs->fragsize = EXT2_FRAG_SIZE(super);
    frags_per_block = fs->blocksize / fs->fragsize;

    /* default: (fs->blocksize*8) blocks/group, up to 2^16 (GDT limit) */
    set_field(s_blocks_per_group, fs->blocksize * 8);
    if (super->s_blocks_per_group > EXT2_MAX_BLOCKS_PER_GROUP(super))
        super->s_blocks_per_group = EXT2_MAX_BLOCKS_PER_GROUP(super);
    super->s_frags_per_group = super->s_blocks_per_group * frags_per_block;

    super->s_blocks_count = param->s_blocks_count;
    super->s_r_blocks_count = param->s_r_blocks_count;
    if (super->s_r_blocks_count >= param->s_blocks_count) {
        retval = EXT2_ET_INVALID_ARGUMENT;
        goto cleanup;
    }

    /*
     * If we're creating an external journal device, we don't need
     * to bother with the rest.
     */
    if (super->s_feature_incompat & EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) {
        fs->group_desc_count = 0;
        ext2fs_mark_super_dirty(fs);
        *ret_fs = fs;
        return 0;
    }

retry:
    fs->group_desc_count = ext2fs_div_ceil(super->s_blocks_count -
                                           super->s_first_data_block,
                                           EXT2_BLOCKS_PER_GROUP(super));
    if (fs->group_desc_count == 0) {
        retval = EXT2_ET_TOOSMALL;
        goto cleanup;
    }
    fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
                                      EXT2_DESC_PER_BLOCK(super));

    i = fs->blocksize >= 4096 ? 1 : 4096 / fs->blocksize;
    set_field(s_inodes_count, super->s_blocks_count / i);

    /*
     * Make sure we have at least EXT2_FIRST_INO + 1 inodes, so
     * that we have enough inodes for the filesystem(!)
     */
    if (super->s_inodes_count < EXT2_FIRST_INODE(super)+1)
        super->s_inodes_count = EXT2_FIRST_INODE(super)+1;

    /*
     * There should be at least as many inodes as the user
     * requested.  Figure out how many inodes per group that
     * should be.  But make sure that we don't allocate more than
     * one bitmap's worth of inodes each group.
     */
    ipg = ext2fs_div_ceil(super->s_inodes_count, fs->group_desc_count);
    if (ipg > fs->blocksize * 8) {
        if (super->s_blocks_per_group >= 256) {
            /* Try again with slightly different parameters */
            super->s_blocks_per_group -= 8;
            super->s_blocks_count = param->s_blocks_count;
            super->s_frags_per_group = super->s_blocks_per_group *
                                       frags_per_block;
            goto retry;
        } else
            return EXT2_ET_TOO_MANY_INODES;
    }

    if (ipg > (unsigned) EXT2_MAX_INODES_PER_GROUP(super))
        ipg = EXT2_MAX_INODES_PER_GROUP(super);

ipg_retry:
    super->s_inodes_per_group = ipg;

    /*
     * Make sure the number of inodes per group completely fills
     * the inode table blocks in the descriptor.  If not, add some
     * additional inodes/group.  Waste not, want not...
     */
    fs->inode_blocks_per_group = (((super->s_inodes_per_group *
                                    EXT2_INODE_SIZE(super)) +
                                   EXT2_BLOCK_SIZE(super) - 1) /
                                  EXT2_BLOCK_SIZE(super));
    super->s_inodes_per_group = ((fs->inode_blocks_per_group *
                                  EXT2_BLOCK_SIZE(super)) /
                                 EXT2_INODE_SIZE(super));
    /*
     * Finally, make sure the number of inodes per group is a
     * multiple of 8.  This is needed to simplify the bitmap
     * splicing code.
     */
    super->s_inodes_per_group &= ~7;
    fs->inode_blocks_per_group = (((super->s_inodes_per_group *
                                    EXT2_INODE_SIZE(super)) +
                                   EXT2_BLOCK_SIZE(super) - 1) /
                                  EXT2_BLOCK_SIZE(super));

    /*
     * adjust inode count to reflect the adjusted inodes_per_group
     */
    if ((__u64)super->s_inodes_per_group * fs->group_desc_count > ~0U) {
        ipg--;
        goto ipg_retry;
    }
    super->s_inodes_count = super->s_inodes_per_group *
                            fs->group_desc_count;
    super->s_free_inodes_count = super->s_inodes_count;

    /*
     * check the number of reserved group descriptor table blocks
     */
    if (super->s_feature_compat & EXT2_FEATURE_COMPAT_RESIZE_INODE)
        rsv_gdt = calc_reserved_gdt_blocks(fs);
    else
        rsv_gdt = 0;
    set_field(s_reserved_gdt_blocks, rsv_gdt);
    if (super->s_reserved_gdt_blocks > EXT2_ADDR_PER_BLOCK(super)) {
        retval = EXT2_ET_RES_GDT_BLOCKS;
        goto cleanup;
    }

    /*
     * Overhead is the number of bookkeeping blocks per group.  It
     * includes the superblock backup, the group descriptor
     * backups, the inode bitmap, the block bitmap, and the inode
     * table.
     */

    overhead = (int) (2 + fs->inode_blocks_per_group);

    if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1))
        overhead += 1 + fs->desc_blocks + super->s_reserved_gdt_blocks;

    /* This can only happen if the user requested too many inodes */
    if (overhead > super->s_blocks_per_group)
        return EXT2_ET_TOO_MANY_INODES;

    /*
     * See if the last group is big enough to support the
     * necessary data structures.  If not, we need to get rid of
     * it.
     */
    rem = ((super->s_blocks_count - super->s_first_data_block) %
           super->s_blocks_per_group);
    if ((fs->group_desc_count == 1) && rem && (rem < overhead))
        return EXT2_ET_TOOSMALL;
    if (rem && (rem < overhead+50)) {
        super->s_blocks_count -= rem;
        goto retry;
    }

    /*
     * At this point we know how big the filesystem will be.  So
     * we can do any and all allocations that depend on the block
     * count.
     */

    retval = ext2fs_get_mem(strlen(fs->device_name) + 80, &buf);
    if (retval)
        goto cleanup;

    sprintf(buf, "block bitmap for %s", fs->device_name);
    retval = ext2fs_allocate_block_bitmap(fs, buf, &fs->block_map);
    if (retval)
        goto cleanup;

    sprintf(buf, "inode bitmap for %s", fs->device_name);
    retval = ext2fs_allocate_inode_bitmap(fs, buf, &fs->inode_map);
    if (retval)
        goto cleanup;

    ext2fs_free_mem(&buf);

    retval = ext2fs_get_mem((size_t) fs->desc_blocks * fs->blocksize,
                            &fs->group_desc);
    if (retval)
        goto cleanup;

    memset(fs->group_desc, 0, (size_t) fs->desc_blocks * fs->blocksize);

    /*
     * Reserve the superblock and group descriptors for each
     * group, and fill in the correct group statistics for group.
     * Note that although the block bitmap, inode bitmap, and
     * inode table have not been allocated (and in fact won't be
     * by this routine), they are accounted for nevertheless.
     */
    super->s_free_blocks_count = 0;
    for (i = 0; i < fs->group_desc_count; i++) {
        numblocks = ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);

        super->s_free_blocks_count += numblocks;
        fs->group_desc[i].bg_free_blocks_count = numblocks;
        fs->group_desc[i].bg_free_inodes_count =
            fs->super->s_inodes_per_group;
        fs->group_desc[i].bg_used_dirs_count = 0;
    }

    c = (char) 255;
    if (((int) c) == -1) {
        super->s_flags |= EXT2_FLAGS_SIGNED_HASH;
    } else {
        super->s_flags |= EXT2_FLAGS_UNSIGNED_HASH;
    }

    ext2fs_mark_super_dirty(fs);
    ext2fs_mark_bb_dirty(fs);
    ext2fs_mark_ib_dirty(fs);

    io_channel_set_blksize(fs->io, fs->blocksize);

    *ret_fs = fs;
    return 0;
cleanup:
    ext2fs_free(fs);
    return retval;
}
Ejemplo n.º 28
0
errcode_t ext2fs_flush(ext2_filsys fs)
{
	dgrp_t		i;
	errcode_t	retval;
	unsigned long	fs_state;
	__u32		feature_incompat;
	struct ext2_super_block *super_shadow = 0;
	struct ext2_group_desc *group_shadow = 0;
#ifdef WORDS_BIGENDIAN
	struct ext2_group_desc *s, *t;
	dgrp_t		j;
#endif
	char	*group_ptr;
	int	old_desc_blocks;

	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);

	fs_state = fs->super->s_state;
	feature_incompat = fs->super->s_feature_incompat;

	fs->super->s_wtime = fs->now ? fs->now : time(NULL);
	fs->super->s_block_group_nr = 0;
#ifdef WORDS_BIGENDIAN
	retval = EXT2_ET_NO_MEMORY;
	retval = ext2fs_get_mem(SUPERBLOCK_SIZE, &super_shadow);
	if (retval)
		goto errout;
	retval = ext2fs_get_array(fs->desc_blocks, fs->blocksize,
				  &group_shadow);
	if (retval)
		goto errout;
	memset(group_shadow, 0, (size_t) fs->blocksize *
	       fs->desc_blocks);

	/* swap the group descriptors */
	for (j=0, s=fs->group_desc, t=group_shadow;
	     j < fs->group_desc_count; j++, t++, s++) {
		*t = *s;
		ext2fs_swap_group_desc(t);
	}
#else
	super_shadow = fs->super;
	group_shadow = fs->group_desc;
#endif

	/*
	 * Set the state of the FS to be non-valid.  (The state has
	 * already been backed up earlier, and will be restored after
	 * we write out the backup superblocks.)
	 */
	fs->super->s_state &= ~EXT2_VALID_FS;
	fs->super->s_feature_incompat &= ~EXT3_FEATURE_INCOMPAT_RECOVER;
#ifdef WORDS_BIGENDIAN
	*super_shadow = *fs->super;
	ext2fs_swap_super(super_shadow);
#endif

	/*
	 * If this is an external journal device, don't write out the
	 * block group descriptors or any of the backup superblocks
	 */
	if (fs->super->s_feature_incompat &
	    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
		goto write_primary_superblock_only;

	/*
	 * Write out the master group descriptors, and the backup
	 * superblocks and group descriptors.
	 */
	group_ptr = (char *) group_shadow;
	if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
		old_desc_blocks = fs->super->s_first_meta_bg;
	else
		old_desc_blocks = fs->desc_blocks;

	for (i = 0; i < fs->group_desc_count; i++) {
		blk64_t	super_blk, old_desc_blk, new_desc_blk;

		ext2fs_super_and_bgd_loc2(fs, i, &super_blk, &old_desc_blk,
					 &new_desc_blk, 0);

		if (!(fs->flags & EXT2_FLAG_MASTER_SB_ONLY) &&i && super_blk) {
			retval = write_backup_super(fs, i, super_blk,
						    super_shadow);
			if (retval)
				goto errout;
		}
		if (fs->flags & EXT2_FLAG_SUPER_ONLY)
			continue;
		if ((old_desc_blk) &&
		    (!(fs->flags & EXT2_FLAG_MASTER_SB_ONLY) || (i == 0))) {
			retval = io_channel_write_blk(fs->io,
			      old_desc_blk, old_desc_blocks, group_ptr);
			if (retval)
				goto errout;
		}
		if (new_desc_blk) {
			int meta_bg = i / EXT2_DESC_PER_BLOCK(fs->super);

			retval = io_channel_write_blk(fs->io, new_desc_blk,
				1, group_ptr + (meta_bg*fs->blocksize));
			if (retval)
				goto errout;
		}
	}

	/*
	 * If the write_bitmaps() function is present, call it to
	 * flush the bitmaps.  This is done this way so that a simple
	 * program that doesn't mess with the bitmaps doesn't need to
	 * drag in the bitmaps.c code.
	 */
	if (fs->write_bitmaps) {
		retval = fs->write_bitmaps(fs);
		if (retval)
			goto errout;
	}

write_primary_superblock_only:
	/*
	 * Write out master superblock.  This has to be done
	 * separately, since it is located at a fixed location
	 * (SUPERBLOCK_OFFSET).  We flush all other pending changes
	 * out to disk first, just to avoid a race condition with an
	 * insy-tinsy window....
	 */

	fs->super->s_block_group_nr = 0;
	fs->super->s_state = fs_state;
	fs->super->s_feature_incompat = feature_incompat;
#ifdef WORDS_BIGENDIAN
	*super_shadow = *fs->super;
	ext2fs_swap_super(super_shadow);
#endif

	retval = io_channel_flush(fs->io);
	retval = write_primary_superblock(fs, super_shadow);
	if (retval)
		goto errout;

	fs->flags &= ~EXT2_FLAG_DIRTY;

	retval = io_channel_flush(fs->io);
errout:
	fs->super->s_state = fs_state;
#ifdef WORDS_BIGENDIAN
	if (super_shadow)
		ext2fs_free_mem(&super_shadow);
	if (group_shadow)
		ext2fs_free_mem(&group_shadow);
#endif
	return retval;
}
Ejemplo n.º 29
0
static int ext2_fill_super(struct super_block *sb, void *data, int silent)
{
	struct buffer_head * bh;
	struct ext2_sb_info * sbi;
	struct ext2_super_block * es;
	struct inode *root;
	unsigned long block;
	unsigned long sb_block = get_sb_block(&data);
	unsigned long logic_sb_block;
	unsigned long offset = 0;
	unsigned long def_mount_opts;
	long ret = -EINVAL;
	int blocksize = BLOCK_SIZE;
	int db_count;
	int i, j;
	__le32 features;
	int err;

	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
	if (!sbi)
		return -ENOMEM;

	sbi->s_blockgroup_lock =
		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
	if (!sbi->s_blockgroup_lock) {
		kfree(sbi);
		return -ENOMEM;
	}
	sb->s_fs_info = sbi;
	sbi->s_sb_block = sb_block;

	/*
	 * See what the current blocksize for the device is, and
	 * use that as the blocksize.  Otherwise (or if the blocksize
	 * is smaller than the default) use the default.
	 * This is important for devices that have a hardware
	 * sectorsize that is larger than the default.
	 */
	blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
	if (!blocksize) {
		printk ("EXT2-fs: unable to set blocksize\n");
		goto failed_sbi;
	}

	/*
	 * If the superblock doesn't start on a hardware sector boundary,
	 * calculate the offset.  
	 */
	if (blocksize != BLOCK_SIZE) {
		logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
		offset = (sb_block*BLOCK_SIZE) % blocksize;
	} else {
		logic_sb_block = sb_block;
	}

	if (!(bh = sb_bread(sb, logic_sb_block))) {
		printk ("EXT2-fs: unable to read superblock\n");
		goto failed_sbi;
	}
	/*
	 * Note: s_es must be initialized as soon as possible because
	 *       some ext2 macro-instructions depend on its value
	 */
	es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
	sbi->s_es = es;
	sb->s_magic = le16_to_cpu(es->s_magic);

	if (sb->s_magic != EXT2_SUPER_MAGIC)
		goto cantfind_ext2;

	/* Set defaults before we parse the mount options */
	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
	if (def_mount_opts & EXT2_DEFM_DEBUG)
		set_opt(sbi->s_mount_opt, DEBUG);
	if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
		set_opt(sbi->s_mount_opt, GRPID);
	if (def_mount_opts & EXT2_DEFM_UID16)
		set_opt(sbi->s_mount_opt, NO_UID32);
#ifdef CONFIG_EXT2_FS_XATTR
	if (def_mount_opts & EXT2_DEFM_XATTR_USER)
		set_opt(sbi->s_mount_opt, XATTR_USER);
#endif
#ifdef CONFIG_EXT2_FS_POSIX_ACL
	if (def_mount_opts & EXT2_DEFM_ACL)
		set_opt(sbi->s_mount_opt, POSIX_ACL);
#endif
	
	if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
		set_opt(sbi->s_mount_opt, ERRORS_PANIC);
	else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
		set_opt(sbi->s_mount_opt, ERRORS_CONT);
	else
		set_opt(sbi->s_mount_opt, ERRORS_RO);

	sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
	sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
	
	set_opt(sbi->s_mount_opt, RESERVATION);

	if (!parse_options ((char *) data, sbi))
		goto failed_mount;

	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
		((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
		 MS_POSIXACL : 0);

	ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
				    EXT2_MOUNT_XIP if not */

	if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
	    (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
	     EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
	     EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
		printk("EXT2-fs warning: feature flags set on rev 0 fs, "
		       "running e2fsck is recommended\n");
	/*
	 * Check feature flags regardless of the revision level, since we
	 * previously didn't change the revision level when setting the flags,
	 * so there is a chance incompat flags are set on a rev 0 filesystem.
	 */
	features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
	if (features) {
		printk("EXT2-fs: %s: couldn't mount because of "
		       "unsupported optional features (%x).\n",
		       sb->s_id, le32_to_cpu(features));
		goto failed_mount;
	}
	if (!(sb->s_flags & MS_RDONLY) &&
	    (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
		printk("EXT2-fs: %s: couldn't mount RDWR because of "
		       "unsupported optional features (%x).\n",
		       sb->s_id, le32_to_cpu(features));
		goto failed_mount;
	}

	blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);

	if (ext2_use_xip(sb) && blocksize != PAGE_SIZE) {
		if (!silent)
			printk("XIP: Unsupported blocksize\n");
		goto failed_mount;
	}

	/* If the blocksize doesn't match, re-read the thing.. */
	if (sb->s_blocksize != blocksize) {
		brelse(bh);

		if (!sb_set_blocksize(sb, blocksize)) {
			printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
			goto failed_sbi;
		}

		logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
		offset = (sb_block*BLOCK_SIZE) % blocksize;
		bh = sb_bread(sb, logic_sb_block);
		if(!bh) {
			printk("EXT2-fs: Couldn't read superblock on "
			       "2nd try.\n");
			goto failed_sbi;
		}
		es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
		sbi->s_es = es;
		if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
			printk ("EXT2-fs: Magic mismatch, very weird !\n");
			goto failed_mount;
		}
	}

	sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);

	if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
		sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
		sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
	} else {
		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
		if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
		    !is_power_of_2(sbi->s_inode_size) ||
		    (sbi->s_inode_size > blocksize)) {
			printk ("EXT2-fs: unsupported inode size: %d\n",
				sbi->s_inode_size);
			goto failed_mount;
		}
	}

	sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
				   le32_to_cpu(es->s_log_frag_size);
	if (sbi->s_frag_size == 0)
		goto cantfind_ext2;
	sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;

	sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
	sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
	sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);

	if (EXT2_INODE_SIZE(sb) == 0)
		goto cantfind_ext2;
	sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
	if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
		goto cantfind_ext2;
	sbi->s_itb_per_group = sbi->s_inodes_per_group /
					sbi->s_inodes_per_block;
	sbi->s_desc_per_block = sb->s_blocksize /
					sizeof (struct ext2_group_desc);
	sbi->s_sbh = bh;
	sbi->s_mount_state = le16_to_cpu(es->s_state);
	sbi->s_addr_per_block_bits =
		ilog2 (EXT2_ADDR_PER_BLOCK(sb));
	sbi->s_desc_per_block_bits =
		ilog2 (EXT2_DESC_PER_BLOCK(sb));

	if (sb->s_magic != EXT2_SUPER_MAGIC)
		goto cantfind_ext2;

	if (sb->s_blocksize != bh->b_size) {
		if (!silent)
			printk ("VFS: Unsupported blocksize on dev "
				"%s.\n", sb->s_id);
		goto failed_mount;
	}

	if (sb->s_blocksize != sbi->s_frag_size) {
		printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
			sbi->s_frag_size, sb->s_blocksize);
		goto failed_mount;
	}

	if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
		printk ("EXT2-fs: #blocks per group too big: %lu\n",
			sbi->s_blocks_per_group);
		goto failed_mount;
	}
	if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
		printk ("EXT2-fs: #fragments per group too big: %lu\n",
			sbi->s_frags_per_group);
		goto failed_mount;
	}
	if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
		printk ("EXT2-fs: #inodes per group too big: %lu\n",
			sbi->s_inodes_per_group);
		goto failed_mount;
	}

	if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
		goto cantfind_ext2;
 	sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
 				le32_to_cpu(es->s_first_data_block) - 1)
 					/ EXT2_BLOCKS_PER_GROUP(sb)) + 1;
	db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
		   EXT2_DESC_PER_BLOCK(sb);
	sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
	if (sbi->s_group_desc == NULL) {
		printk ("EXT2-fs: not enough memory\n");
		goto failed_mount;
	}
	bgl_lock_init(sbi->s_blockgroup_lock);
	sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
	if (!sbi->s_debts) {
		printk ("EXT2-fs: not enough memory\n");
		goto failed_mount_group_desc;
	}
	for (i = 0; i < db_count; i++) {
		block = descriptor_loc(sb, logic_sb_block, i);
		sbi->s_group_desc[i] = sb_bread(sb, block);
		if (!sbi->s_group_desc[i]) {
			for (j = 0; j < i; j++)
				brelse (sbi->s_group_desc[j]);
			printk ("EXT2-fs: unable to read group descriptors\n");
			goto failed_mount_group_desc;
		}
	}
	if (!ext2_check_descriptors (sb)) {
		printk ("EXT2-fs: group descriptors corrupted!\n");
		goto failed_mount2;
	}
	sbi->s_gdb_count = db_count;
	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
	spin_lock_init(&sbi->s_next_gen_lock);

	/* per fileystem reservation list head & lock */
	spin_lock_init(&sbi->s_rsv_window_lock);
	sbi->s_rsv_window_root = RB_ROOT;
	/*
	 * Add a single, static dummy reservation to the start of the
	 * reservation window list --- it gives us a placeholder for
	 * append-at-start-of-list which makes the allocation logic
	 * _much_ simpler.
	 */
	sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
	sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
	sbi->s_rsv_window_head.rsv_alloc_hit = 0;
	sbi->s_rsv_window_head.rsv_goal_size = 0;
	ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);

	err = percpu_counter_init(&sbi->s_freeblocks_counter,
				ext2_count_free_blocks(sb));
	if (!err) {
		err = percpu_counter_init(&sbi->s_freeinodes_counter,
				ext2_count_free_inodes(sb));
	}
	if (!err) {
		err = percpu_counter_init(&sbi->s_dirs_counter,
				ext2_count_dirs(sb));
	}
	if (err) {
		printk(KERN_ERR "EXT2-fs: insufficient memory\n");
		goto failed_mount3;
	}
	/*
	 * set up enough so that it can read an inode
	 */
	sb->s_op = &ext2_sops;
	sb->s_export_op = &ext2_export_ops;
	sb->s_xattr = ext2_xattr_handlers;
	root = ext2_iget(sb, EXT2_ROOT_INO);
	if (IS_ERR(root)) {
		ret = PTR_ERR(root);
		goto failed_mount3;
	}
	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
		iput(root);
		printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
		goto failed_mount3;
	}

	sb->s_root = d_alloc_root(root);
	if (!sb->s_root) {
		iput(root);
		printk(KERN_ERR "EXT2-fs: get root inode failed\n");
		ret = -ENOMEM;
		goto failed_mount3;
	}
	if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
		ext2_warning(sb, __func__,
			"mounting ext3 filesystem as ext2");
	ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
	return 0;

cantfind_ext2:
	if (!silent)
		printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
		       sb->s_id);
	goto failed_mount;
failed_mount3:
	percpu_counter_destroy(&sbi->s_freeblocks_counter);
	percpu_counter_destroy(&sbi->s_freeinodes_counter);
	percpu_counter_destroy(&sbi->s_dirs_counter);
failed_mount2:
	for (i = 0; i < db_count; i++)
		brelse(sbi->s_group_desc[i]);
failed_mount_group_desc:
	kfree(sbi->s_group_desc);
	kfree(sbi->s_debts);
failed_mount:
	brelse(bh);
failed_sbi:
	sb->s_fs_info = NULL;
	kfree(sbi->s_blockgroup_lock);
	kfree(sbi);
	return ret;
}
Ejemplo n.º 30
0
/*
 * This computes the fields of the  ext2_sb_info structure from the
 * data in the ext2_super_block structure read in.
 */
static int
compute_sb_data(struct vnode *devvp, struct ext2fs *es,
    struct m_ext2fs *fs)
{
	int db_count, error;
	int i;
	int logic_sb_block = 1;	/* XXX for now */
	struct buf *bp;

	fs->e2fs_bsize = EXT2_MIN_BLOCK_SIZE << es->e2fs_log_bsize;
	fs->e2fs_bshift = EXT2_MIN_BLOCK_LOG_SIZE + es->e2fs_log_bsize;
	fs->e2fs_fsbtodb = es->e2fs_log_bsize + 1;
	fs->e2fs_qbmask = fs->e2fs_bsize - 1;
	fs->e2fs_blocksize_bits = es->e2fs_log_bsize + 10;
	fs->e2fs_fsize = EXT2_MIN_FRAG_SIZE << es->e2fs_log_fsize;
	if (fs->e2fs_fsize)
		fs->e2fs_fpb = fs->e2fs_bsize / fs->e2fs_fsize;
	fs->e2fs_bpg = es->e2fs_bpg;
	fs->e2fs_fpg = es->e2fs_fpg;
	fs->e2fs_ipg = es->e2fs_ipg;
	if (es->e2fs_rev == E2FS_REV0) {
		fs->e2fs_first_inode = EXT2_FIRSTINO;
		fs->e2fs_isize = E2FS_REV0_INODE_SIZE ;
	} else {
		fs->e2fs_first_inode = es->e2fs_first_ino;
		fs->e2fs_isize = es->e2fs_inode_size;

		/*
		 * Simple sanity check for superblock inode size value.
		 */
		if (EXT2_INODE_SIZE(fs) < E2FS_REV0_INODE_SIZE ||
		    EXT2_INODE_SIZE(fs) > fs->e2fs_bsize ||
		    (fs->e2fs_isize & (fs->e2fs_isize - 1)) != 0) {
			printf("ext2fs: invalid inode size %d\n",
			    fs->e2fs_isize);
			return (EIO);
		}
	}
	/* Check for extra isize in big inodes. */
	if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT4F_ROCOMPAT_EXTRA_ISIZE) &&
	    EXT2_INODE_SIZE(fs) < sizeof(struct ext2fs_dinode)) {
		printf("ext2fs: no space for extra inode timestamps\n");
		return (EINVAL);
	}

	fs->e2fs_ipb = fs->e2fs_bsize / EXT2_INODE_SIZE(fs);
	fs->e2fs_itpg = fs->e2fs_ipg /fs->e2fs_ipb;
	fs->e2fs_descpb = fs->e2fs_bsize / sizeof(struct ext2_gd);
	/* s_resuid / s_resgid ? */
	fs->e2fs_gcount = (es->e2fs_bcount - es->e2fs_first_dblock +
	    EXT2_BLOCKS_PER_GROUP(fs) - 1) / EXT2_BLOCKS_PER_GROUP(fs);
	db_count = (fs->e2fs_gcount + EXT2_DESC_PER_BLOCK(fs) - 1) /
	    EXT2_DESC_PER_BLOCK(fs);
	fs->e2fs_gdbcount = db_count;
	fs->e2fs_gd = malloc(db_count * fs->e2fs_bsize,
	    M_EXT2MNT, M_WAITOK);
	fs->e2fs_contigdirs = malloc(fs->e2fs_gcount *
	    sizeof(*fs->e2fs_contigdirs), M_EXT2MNT, M_WAITOK);

	/*
	 * Adjust logic_sb_block.
	 * Godmar thinks: if the blocksize is greater than 1024, then
	 * the superblock is logically part of block zero.
	 */
	if(fs->e2fs_bsize > SBSIZE)
		logic_sb_block = 0;
	for (i = 0; i < db_count; i++) {
		error = bread(devvp ,
			 fsbtodb(fs, logic_sb_block + i + 1 ),
			fs->e2fs_bsize, NOCRED, &bp);
		if (error) {
			free(fs->e2fs_gd, M_EXT2MNT);
			brelse(bp);
			return (error);
		}
		e2fs_cgload((struct ext2_gd *)bp->b_data,
		    &fs->e2fs_gd[
			i * fs->e2fs_bsize / sizeof(struct ext2_gd)],
		    fs->e2fs_bsize);
		brelse(bp);
		bp = NULL;
	}
	fs->e2fs_total_dir = 0;
	for (i=0; i < fs->e2fs_gcount; i++){
		fs->e2fs_total_dir += fs->e2fs_gd[i].ext2bgd_ndirs;
		fs->e2fs_contigdirs[i] = 0;
	}
	if (es->e2fs_rev == E2FS_REV0 ||
	    !EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_LARGEFILE))
		fs->e2fs_maxfilesize = 0x7fffffff;
	else
		fs->e2fs_maxfilesize = 0x7fffffffffffffff;
	return (0);
}