Commit 25ed6e8a authored by Darrick J. Wong's avatar Darrick J. Wong Committed by Theodore Ts'o
Browse files

jbd2: enable journal clients to enable v2 checksumming 



Add in the necessary code so that journal clients can enable the new
journal checksumming features.

Signed-off-by: default avatarDarrick J. Wong <djwong@us.ibm.com>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
parent 8f888ef8

fs/ext4/super.c

+42 −13
Original line number Diff line number Diff line
@@ -3013,6 +3013,44 @@ static void ext4_destroy_lazyinit_thread(void) 
	kthread_stop(ext4_lazyinit_task);

}



static int set_journal_csum_feature_set(struct super_block *sb)

{

	int ret = 1;

	int compat, incompat;

	struct ext4_sb_info *sbi = EXT4_SB(sb);



	if (EXT4_HAS_RO_COMPAT_FEATURE(sb,

				       EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {

		/* journal checksum v2 */

		compat = 0;

		incompat = JBD2_FEATURE_INCOMPAT_CSUM_V2;

	} else {

		/* journal checksum v1 */

		compat = JBD2_FEATURE_COMPAT_CHECKSUM;

		incompat = 0;

	}



	if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {

		ret = jbd2_journal_set_features(sbi->s_journal,

				compat, 0,

				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |

				incompat);

	} else if (test_opt(sb, JOURNAL_CHECKSUM)) {

		ret = jbd2_journal_set_features(sbi->s_journal,

				compat, 0,

				incompat);

		jbd2_journal_clear_features(sbi->s_journal, 0, 0,

				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);

	} else {

		jbd2_journal_clear_features(sbi->s_journal,

				JBD2_FEATURE_COMPAT_CHECKSUM, 0,

				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |

				JBD2_FEATURE_INCOMPAT_CSUM_V2);

	}



	return ret;

}



static int ext4_fill_super(struct super_block *sb, void *data, int silent)

{

	char *orig_data = kstrdup(data, GFP_KERNEL);
@@ -3610,19 +3648,10 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) 
		goto failed_mount_wq;

	}



	if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {

		jbd2_journal_set_features(sbi->s_journal,

				JBD2_FEATURE_COMPAT_CHECKSUM, 0,

				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);

	} else if (test_opt(sb, JOURNAL_CHECKSUM)) {

		jbd2_journal_set_features(sbi->s_journal,

				JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);

		jbd2_journal_clear_features(sbi->s_journal, 0, 0,

				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);

	} else {

		jbd2_journal_clear_features(sbi->s_journal,

				JBD2_FEATURE_COMPAT_CHECKSUM, 0,

				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);

	if (!set_journal_csum_feature_set(sb)) {

		ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "

			 "feature set");

		goto failed_mount_wq;

	}



	/* We have now updated the journal if required, so we can

fs/jbd2/journal.c

+50 −0
Original line number Diff line number Diff line
@@ -97,6 +97,15 @@ EXPORT_SYMBOL(jbd2_inode_cache); 
static void __journal_abort_soft (journal_t *journal, int errno);

static int jbd2_journal_create_slab(size_t slab_size);



/* Checksumming functions */

int jbd2_verify_csum_type(journal_t *j, journal_superblock_t *sb)

{

	if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2))

		return 1;



	return sb->s_checksum_type == JBD2_CRC32C_CHKSUM;

}



/*

 * Helper function used to manage commit timeouts

 */
@@ -1376,6 +1385,9 @@ static int journal_get_superblock(journal_t *journal) 
		}

	}



	if (buffer_verified(bh))

		return 0;



	sb = journal->j_superblock;



	err = -EINVAL;
@@ -1413,6 +1425,21 @@ static int journal_get_superblock(journal_t *journal) 
		goto out;

	}



	if (JBD2_HAS_COMPAT_FEATURE(journal, JBD2_FEATURE_COMPAT_CHECKSUM) &&

	    JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V2)) {

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

		printk(KERN_ERR "JBD: Can't enable checksumming v1 and v2 "

		       "at the same time!\n");

		goto out;

	}



	if (!jbd2_verify_csum_type(journal, sb)) {

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

		goto out;

	}



	set_buffer_verified(bh);



	return 0;



out:
@@ -1653,6 +1680,10 @@ int jbd2_journal_check_available_features (journal_t *journal, unsigned long com 
int jbd2_journal_set_features (journal_t *journal, unsigned long compat,

			  unsigned long ro, unsigned long incompat)

{

#define INCOMPAT_FEATURE_ON(f) \

		((incompat & (f)) && !(sb->s_feature_incompat & cpu_to_be32(f)))

#define COMPAT_FEATURE_ON(f) \

		((compat & (f)) && !(sb->s_feature_compat & cpu_to_be32(f)))

	journal_superblock_t *sb;



	if (jbd2_journal_check_used_features(journal, compat, ro, incompat))
@@ -1661,16 +1692,35 @@ int jbd2_journal_set_features (journal_t *journal, unsigned long compat, 
	if (!jbd2_journal_check_available_features(journal, compat, ro, incompat))

		return 0;



	/* Asking for checksumming v2 and v1?  Only give them v2. */

	if (incompat & JBD2_FEATURE_INCOMPAT_CSUM_V2 &&

	    compat & JBD2_FEATURE_COMPAT_CHECKSUM)

		compat &= ~JBD2_FEATURE_COMPAT_CHECKSUM;



	jbd_debug(1, "Setting new features 0x%lx/0x%lx/0x%lx\n",

		  compat, ro, incompat);



	sb = journal->j_superblock;



	/* If enabling v2 checksums, update superblock */

	if (INCOMPAT_FEATURE_ON(JBD2_FEATURE_INCOMPAT_CSUM_V2)) {

		sb->s_checksum_type = JBD2_CRC32C_CHKSUM;

		sb->s_feature_compat &=

			~cpu_to_be32(JBD2_FEATURE_COMPAT_CHECKSUM);

	}



	/* If enabling v1 checksums, downgrade superblock */

	if (COMPAT_FEATURE_ON(JBD2_FEATURE_COMPAT_CHECKSUM))

		sb->s_feature_incompat &=

			~cpu_to_be32(JBD2_FEATURE_INCOMPAT_CSUM_V2);



	sb->s_feature_compat    |= cpu_to_be32(compat);

	sb->s_feature_ro_compat |= cpu_to_be32(ro);

	sb->s_feature_incompat  |= cpu_to_be32(incompat);



	return 1;

#undef COMPAT_FEATURE_ON

#undef INCOMPAT_FEATURE_ON

}



/*