Commit bc62dbf9 authored by Jason Yan's avatar Jason Yan Committed by Theodore Ts'o
Browse files

ext4: factor out ext4_geometry_check() 



Factor out ext4_geometry_check(). No functional change.

Signed-off-by: default avatarJason Yan <yanaijie@huawei.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarRitesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20220916141527.1012715-11-yanaijie@huawei.com


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent d7f3542b

fs/ext4/super.c

+61 −50
Original line number Diff line number Diff line
@@ -4660,6 +4660,66 @@ static int ext4_check_feature_compatibility(struct super_block *sb, 
	return 0;

}



static int ext4_geometry_check(struct super_block *sb,

			       struct ext4_super_block *es)

{

	struct ext4_sb_info *sbi = EXT4_SB(sb);

	__u64 blocks_count;



	/* check blocks count against device size */

	blocks_count = sb_bdev_nr_blocks(sb);

	if (blocks_count && ext4_blocks_count(es) > blocks_count) {

		ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "

		       "exceeds size of device (%llu blocks)",

		       ext4_blocks_count(es), blocks_count);

		return -EINVAL;

	}



	/*

	 * It makes no sense for the first data block to be beyond the end

	 * of the filesystem.

	 */

	if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {

		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "

			 "block %u is beyond end of filesystem (%llu)",

			 le32_to_cpu(es->s_first_data_block),

			 ext4_blocks_count(es));

		return -EINVAL;

	}

	if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&

	    (sbi->s_cluster_ratio == 1)) {

		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "

			 "block is 0 with a 1k block and cluster size");

		return -EINVAL;

	}



	blocks_count = (ext4_blocks_count(es) -

			le32_to_cpu(es->s_first_data_block) +

			EXT4_BLOCKS_PER_GROUP(sb) - 1);

	do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));

	if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {

		ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "

		       "(block count %llu, first data block %u, "

		       "blocks per group %lu)", blocks_count,

		       ext4_blocks_count(es),

		       le32_to_cpu(es->s_first_data_block),

		       EXT4_BLOCKS_PER_GROUP(sb));

		return -EINVAL;

	}

	sbi->s_groups_count = blocks_count;

	sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,

			(EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));

	if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=

	    le32_to_cpu(es->s_inodes_count)) {

		ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",

			 le32_to_cpu(es->s_inodes_count),

			 ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));

		return -EINVAL;

	}



	return 0;

}



static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)

{

	struct buffer_head *bh, **group_desc;
@@ -4675,7 +4735,6 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb) 
	unsigned int db_count;

	unsigned int i;

	int needs_recovery, has_huge_files;

	__u64 blocks_count;

	int err = 0;

	ext4_group_t first_not_zeroed;

	struct ext4_fs_context *ctx = fc->fs_private;
@@ -4964,57 +5023,9 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb) 
		goto failed_mount;

	}



	/* check blocks count against device size */

	blocks_count = sb_bdev_nr_blocks(sb);

	if (blocks_count && ext4_blocks_count(es) > blocks_count) {

		ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "

		       "exceeds size of device (%llu blocks)",

		       ext4_blocks_count(es), blocks_count);

		goto failed_mount;

	}



	/*

	 * It makes no sense for the first data block to be beyond the end

	 * of the filesystem.

	 */

	if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {

		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "

			 "block %u is beyond end of filesystem (%llu)",

			 le32_to_cpu(es->s_first_data_block),

			 ext4_blocks_count(es));

		goto failed_mount;

	}

	if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&

	    (sbi->s_cluster_ratio == 1)) {

		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "

			 "block is 0 with a 1k block and cluster size");

	if (ext4_geometry_check(sb, es))

		goto failed_mount;

	}



	blocks_count = (ext4_blocks_count(es) -

			le32_to_cpu(es->s_first_data_block) +

			EXT4_BLOCKS_PER_GROUP(sb) - 1);

	do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));

	if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {

		ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "

		       "(block count %llu, first data block %u, "

		       "blocks per group %lu)", blocks_count,

		       ext4_blocks_count(es),

		       le32_to_cpu(es->s_first_data_block),

		       EXT4_BLOCKS_PER_GROUP(sb));

		goto failed_mount;

	}

	sbi->s_groups_count = blocks_count;

	sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,

			(EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));

	if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=

	    le32_to_cpu(es->s_inodes_count)) {

		ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",

			 le32_to_cpu(es->s_inodes_count),

			 ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));

		ret = -EINVAL;

		goto failed_mount;

	}

	db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /

		   EXT4_DESC_PER_BLOCK(sb);

	if (ext4_has_feature_meta_bg(sb)) {