Commit 29a511e4 authored by Zhang Yi's avatar Zhang Yi Committed by Theodore Ts'o
Browse files

jbd2: move load_superblock() dependent functions 



Move load_superblock() declaration and the functions it calls before
journal_init_common(). This is a preparation for moving a call to
load_superblock() from jbd2_journal_load() and jbd2_journal_wipe() to
journal_init_common(). No functional changes.

Signed-off-by: default avatarZhang Yi <yi.zhang@huawei.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230811063610.2980059-2-yi.zhang@huaweicloud.com


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 772c9f69

fs/jbd2/journal.c

+168 −169
Original line number Diff line number Diff line
@@ -1336,6 +1336,174 @@ static unsigned long jbd2_journal_shrink_count(struct shrinker *shrink, 
	return count;

}



/*

 * If the journal init or create aborts, we need to mark the journal

 * superblock as being NULL to prevent the journal destroy from writing

 * back a bogus superblock.

 */

static void journal_fail_superblock(journal_t *journal)

{

	struct buffer_head *bh = journal->j_sb_buffer;

	brelse(bh);

	journal->j_sb_buffer = NULL;

}



/*

 * Read the superblock for a given journal, performing initial

 * validation of the format.

 */

static int journal_get_superblock(journal_t *journal)

{

	struct buffer_head *bh;

	journal_superblock_t *sb;

	int err;



	bh = journal->j_sb_buffer;



	J_ASSERT(bh != NULL);

	if (buffer_verified(bh))

		return 0;



	err = bh_read(bh, 0);

	if (err < 0) {

		printk(KERN_ERR

			"JBD2: IO error reading journal superblock\n");

		goto out;

	}



	sb = journal->j_superblock;



	err = -EINVAL;



	if (sb->s_header.h_magic != cpu_to_be32(JBD2_MAGIC_NUMBER) ||

	    sb->s_blocksize != cpu_to_be32(journal->j_blocksize)) {

		printk(KERN_WARNING "JBD2: no valid journal superblock found\n");

		goto out;

	}



	if (be32_to_cpu(sb->s_header.h_blocktype) != JBD2_SUPERBLOCK_V1 &&

	    be32_to_cpu(sb->s_header.h_blocktype) != JBD2_SUPERBLOCK_V2) {

		printk(KERN_WARNING "JBD2: unrecognised superblock format ID\n");

		goto out;

	}



	if (be32_to_cpu(sb->s_maxlen) > journal->j_total_len) {

		printk(KERN_WARNING "JBD2: journal file too short\n");

		goto out;

	}



	if (be32_to_cpu(sb->s_first) == 0 ||

	    be32_to_cpu(sb->s_first) >= journal->j_total_len) {

		printk(KERN_WARNING

			"JBD2: Invalid start block of journal: %u\n",

			be32_to_cpu(sb->s_first));

		goto out;

	}



	if (jbd2_has_feature_csum2(journal) &&

	    jbd2_has_feature_csum3(journal)) {

		/* Can't have checksum v2 and v3 at the same time! */

		printk(KERN_ERR "JBD2: Can't enable checksumming v2 and v3 "

		       "at the same time!\n");

		goto out;

	}



	if (jbd2_journal_has_csum_v2or3_feature(journal) &&

	    jbd2_has_feature_checksum(journal)) {

		/* Can't have checksum v1 and v2 on at the same time! */

		printk(KERN_ERR "JBD2: Can't enable checksumming v1 and v2/3 "

		       "at the same time!\n");

		goto out;

	}



	if (!jbd2_verify_csum_type(journal, sb)) {

		printk(KERN_ERR "JBD2: Unknown checksum type\n");

		goto out;

	}



	/* Load the checksum driver */

	if (jbd2_journal_has_csum_v2or3_feature(journal)) {

		journal->j_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);

		if (IS_ERR(journal->j_chksum_driver)) {

			printk(KERN_ERR "JBD2: Cannot load crc32c driver.\n");

			err = PTR_ERR(journal->j_chksum_driver);

			journal->j_chksum_driver = NULL;

			goto out;

		}

		/* Check superblock checksum */

		if (sb->s_checksum != jbd2_superblock_csum(journal, sb)) {

			printk(KERN_ERR "JBD2: journal checksum error\n");

			err = -EFSBADCRC;

			goto out;

		}

	}

	set_buffer_verified(bh);

	return 0;



out:

	journal_fail_superblock(journal);

	return err;

}



static int journal_revoke_records_per_block(journal_t *journal)

{

	int record_size;

	int space = journal->j_blocksize - sizeof(jbd2_journal_revoke_header_t);



	if (jbd2_has_feature_64bit(journal))

		record_size = 8;

	else

		record_size = 4;



	if (jbd2_journal_has_csum_v2or3(journal))

		space -= sizeof(struct jbd2_journal_block_tail);

	return space / record_size;

}



/*

 * Load the on-disk journal superblock and read the key fields into the

 * journal_t.

 */

static int load_superblock(journal_t *journal)

{

	int err;

	journal_superblock_t *sb;

	int num_fc_blocks;



	err = journal_get_superblock(journal);

	if (err)

		return err;



	sb = journal->j_superblock;



	journal->j_tail_sequence = be32_to_cpu(sb->s_sequence);

	journal->j_tail = be32_to_cpu(sb->s_start);

	journal->j_first = be32_to_cpu(sb->s_first);

	journal->j_errno = be32_to_cpu(sb->s_errno);

	journal->j_last = be32_to_cpu(sb->s_maxlen);



	if (be32_to_cpu(sb->s_maxlen) < journal->j_total_len)

		journal->j_total_len = be32_to_cpu(sb->s_maxlen);

	/* Precompute checksum seed for all metadata */

	if (jbd2_journal_has_csum_v2or3(journal))

		journal->j_csum_seed = jbd2_chksum(journal, ~0, sb->s_uuid,

						   sizeof(sb->s_uuid));

	journal->j_revoke_records_per_block =

				journal_revoke_records_per_block(journal);



	if (jbd2_has_feature_fast_commit(journal)) {

		journal->j_fc_last = be32_to_cpu(sb->s_maxlen);

		num_fc_blocks = jbd2_journal_get_num_fc_blks(sb);

		if (journal->j_last - num_fc_blocks >= JBD2_MIN_JOURNAL_BLOCKS)

			journal->j_last = journal->j_fc_last - num_fc_blocks;

		journal->j_fc_first = journal->j_last + 1;

		journal->j_fc_off = 0;

	}



	return 0;

}





/*

 * Management for journal control blocks: functions to create and

 * destroy journal_t structures, and to initialise and read existing
@@ -1521,18 +1689,6 @@ journal_t *jbd2_journal_init_inode(struct inode *inode) 
	return journal;

}



/*

 * If the journal init or create aborts, we need to mark the journal

 * superblock as being NULL to prevent the journal destroy from writing

 * back a bogus superblock.

 */

static void journal_fail_superblock(journal_t *journal)

{

	struct buffer_head *bh = journal->j_sb_buffer;

	brelse(bh);

	journal->j_sb_buffer = NULL;

}



/*

 * Given a journal_t structure, initialise the various fields for

 * startup of a new journaling session.  We use this both when creating
@@ -1889,163 +2045,6 @@ void jbd2_journal_update_sb_errno(journal_t *journal) 
}

EXPORT_SYMBOL(jbd2_journal_update_sb_errno);



static int journal_revoke_records_per_block(journal_t *journal)

{

	int record_size;

	int space = journal->j_blocksize - sizeof(jbd2_journal_revoke_header_t);



	if (jbd2_has_feature_64bit(journal))

		record_size = 8;

	else

		record_size = 4;



	if (jbd2_journal_has_csum_v2or3(journal))

		space -= sizeof(struct jbd2_journal_block_tail);

	return space / record_size;

}



/*

 * Read the superblock for a given journal, performing initial

 * validation of the format.

 */

static int journal_get_superblock(journal_t *journal)

{

	struct buffer_head *bh;

	journal_superblock_t *sb;

	int err;



	bh = journal->j_sb_buffer;



	J_ASSERT(bh != NULL);

	if (buffer_verified(bh))

		return 0;



	err = bh_read(bh, 0);

	if (err < 0) {

		printk(KERN_ERR

			"JBD2: IO error reading journal superblock\n");

		goto out;

	}



	sb = journal->j_superblock;



	err = -EINVAL;



	if (sb->s_header.h_magic != cpu_to_be32(JBD2_MAGIC_NUMBER) ||

	    sb->s_blocksize != cpu_to_be32(journal->j_blocksize)) {

		printk(KERN_WARNING "JBD2: no valid journal superblock found\n");

		goto out;

	}



	if (be32_to_cpu(sb->s_header.h_blocktype) != JBD2_SUPERBLOCK_V1 &&

	    be32_to_cpu(sb->s_header.h_blocktype) != JBD2_SUPERBLOCK_V2) {

		printk(KERN_WARNING "JBD2: unrecognised superblock format ID\n");

		goto out;

	}



	if (be32_to_cpu(sb->s_maxlen) > journal->j_total_len) {

		printk(KERN_WARNING "JBD2: journal file too short\n");

		goto out;

	}



	if (be32_to_cpu(sb->s_first) == 0 ||

	    be32_to_cpu(sb->s_first) >= journal->j_total_len) {

		printk(KERN_WARNING

			"JBD2: Invalid start block of journal: %u\n",

			be32_to_cpu(sb->s_first));

		goto out;

	}



	if (jbd2_has_feature_csum2(journal) &&

	    jbd2_has_feature_csum3(journal)) {

		/* Can't have checksum v2 and v3 at the same time! */

		printk(KERN_ERR "JBD2: Can't enable checksumming v2 and v3 "

		       "at the same time!\n");

		goto out;

	}



	if (jbd2_journal_has_csum_v2or3_feature(journal) &&

	    jbd2_has_feature_checksum(journal)) {

		/* Can't have checksum v1 and v2 on at the same time! */

		printk(KERN_ERR "JBD2: Can't enable checksumming v1 and v2/3 "

		       "at the same time!\n");

		goto out;

	}



	if (!jbd2_verify_csum_type(journal, sb)) {

		printk(KERN_ERR "JBD2: Unknown checksum type\n");

		goto out;

	}



	/* Load the checksum driver */

	if (jbd2_journal_has_csum_v2or3_feature(journal)) {

		journal->j_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);

		if (IS_ERR(journal->j_chksum_driver)) {

			printk(KERN_ERR "JBD2: Cannot load crc32c driver.\n");

			err = PTR_ERR(journal->j_chksum_driver);

			journal->j_chksum_driver = NULL;

			goto out;

		}

		/* Check superblock checksum */

		if (sb->s_checksum != jbd2_superblock_csum(journal, sb)) {

			printk(KERN_ERR "JBD2: journal checksum error\n");

			err = -EFSBADCRC;

			goto out;

		}

	}

	set_buffer_verified(bh);

	return 0;



out:

	journal_fail_superblock(journal);

	return err;

}



/*

 * Load the on-disk journal superblock and read the key fields into the

 * journal_t.

 */



static int load_superblock(journal_t *journal)

{

	int err;

	journal_superblock_t *sb;

	int num_fc_blocks;



	err = journal_get_superblock(journal);

	if (err)

		return err;



	sb = journal->j_superblock;



	journal->j_tail_sequence = be32_to_cpu(sb->s_sequence);

	journal->j_tail = be32_to_cpu(sb->s_start);

	journal->j_first = be32_to_cpu(sb->s_first);

	journal->j_errno = be32_to_cpu(sb->s_errno);

	journal->j_last = be32_to_cpu(sb->s_maxlen);



	if (be32_to_cpu(sb->s_maxlen) < journal->j_total_len)

		journal->j_total_len = be32_to_cpu(sb->s_maxlen);

	/* Precompute checksum seed for all metadata */

	if (jbd2_journal_has_csum_v2or3(journal))

		journal->j_csum_seed = jbd2_chksum(journal, ~0, sb->s_uuid,

						   sizeof(sb->s_uuid));

	journal->j_revoke_records_per_block =

				journal_revoke_records_per_block(journal);



	if (jbd2_has_feature_fast_commit(journal)) {

		journal->j_fc_last = be32_to_cpu(sb->s_maxlen);

		num_fc_blocks = jbd2_journal_get_num_fc_blks(sb);

		if (journal->j_last - num_fc_blocks >= JBD2_MIN_JOURNAL_BLOCKS)

			journal->j_last = journal->j_fc_last - num_fc_blocks;

		journal->j_fc_first = journal->j_last + 1;

		journal->j_fc_off = 0;

	}



	return 0;

}





/**

 * jbd2_journal_load() - Read journal from disk.

 * @journal: Journal to act on.