[PATCH 1/3] ext4: fold ext4_sync_fs_nojournal() into ext4_sync_fs()

[PATCH 1/3] ext4: fold ext4_sync_fs_nojournal() into ext4_sync_fs()

[Theodore Ts'o]

This allows us to eliminate duplicate code, and eventually allow us to
also fold ext4_sops and ext4_nojournal_sops together.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---
 fs/ext4/super.c | 36 +++++++++++++-----------------------
 1 file changed, 13 insertions(+), 23 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 115e27d..4770c98 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -70,7 +70,6 @@ static void ext4_mark_recovery_complete(struct super_block *sb,
 static void ext4_clear_journal_err(struct super_block *sb,
 				   struct ext4_super_block *es);
 static int ext4_sync_fs(struct super_block *sb, int wait);
-static int ext4_sync_fs_nojournal(struct super_block *sb, int wait);
 static int ext4_remount(struct super_block *sb, int *flags, char *data);
 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
 static int ext4_unfreeze(struct super_block *sb);
@@ -1131,7 +1130,7 @@ static const struct super_operations ext4_nojournal_sops = {
 	.dirty_inode	= ext4_dirty_inode,
 	.drop_inode	= ext4_drop_inode,
 	.evict_inode	= ext4_evict_inode,
-	.sync_fs	= ext4_sync_fs_nojournal,
+	.sync_fs	= ext4_sync_fs,
 	.put_super	= ext4_put_super,
 	.statfs		= ext4_statfs,
 	.remount_fs	= ext4_remount,
@@ -4718,15 +4717,19 @@ static int ext4_sync_fs(struct super_block *sb, int wait)
 	 * being sent at the end of the function. But we can skip it if
 	 * transaction_commit will do it for us.
 	 */
-	target = jbd2_get_latest_transaction(sbi->s_journal);
-	if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
-	    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
+	if (sbi->s_journal) {
+		target = jbd2_get_latest_transaction(sbi->s_journal);
+		if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
+		    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
+			needs_barrier = true;
+
+		if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
+			if (wait)
+				ret = jbd2_log_wait_commit(sbi->s_journal,
+							   target);
+		}
+	} else if (wait && test_opt(sb, BARRIER))
 		needs_barrier = true;
-
-	if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
-		if (wait)
-			ret = jbd2_log_wait_commit(sbi->s_journal, target);
-	}
 	if (needs_barrier) {
 		int err;
 		err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
@@ -4737,19 +4740,6 @@ static int ext4_sync_fs(struct super_block *sb, int wait)
 	return ret;
 }
 
-static int ext4_sync_fs_nojournal(struct super_block *sb, int wait)
-{
-	int ret = 0;
-
-	trace_ext4_sync_fs(sb, wait);
-	flush_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
-	dquot_writeback_dquots(sb, -1);
-	if (wait && test_opt(sb, BARRIER))
-		ret = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
-
-	return ret;
-}

[PATCH 2/3] ext4: support freezing ext2 (nojournal) file systems

[Theodore Ts'o]

Through an oversight, when we added nojournal support to ext4, we
didn't add support to allow file system freezing.  This is relatively
easy to add, so let's do it.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Dexuan Cui <decui@microsoft.com>
---
 fs/ext4/super.c | 27 ++++++++++++++++-----------
 1 file changed, 16 insertions(+), 11 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 4770c98..921d5b4 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1131,6 +1131,8 @@ static const struct super_operations ext4_nojournal_sops = {
 	.drop_inode	= ext4_drop_inode,
 	.evict_inode	= ext4_evict_inode,
 	.sync_fs	= ext4_sync_fs,
+	.freeze_fs	= ext4_freeze,
+	.unfreeze_fs	= ext4_unfreeze,
 	.put_super	= ext4_put_super,
 	.statfs		= ext4_statfs,
 	.remount_fs	= ext4_remount,
@@ -4758,23 +4760,26 @@ static int ext4_freeze(struct super_block *sb)
 
 	journal = EXT4_SB(sb)->s_journal;
 
-	/* Now we set up the journal barrier. */
-	jbd2_journal_lock_updates(journal);
+	if (journal) {
+		/* Now we set up the journal barrier. */
+		jbd2_journal_lock_updates(journal);
 
-	/*
-	 * Don't clear the needs_recovery flag if we failed to flush
-	 * the journal.
-	 */
-	error = jbd2_journal_flush(journal);
-	if (error < 0)
-		goto out;
+		/*
+		 * Don't clear the needs_recovery flag if we failed to
+		 * flush the journal.
+		 */
+		error = jbd2_journal_flush(journal);
+		if (error < 0)
+			goto out;
+	}
 
 	/* Journal blocked and flushed, clear needs_recovery flag. */
 	EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 	error = ext4_commit_super(sb, 1);
 out:
-	/* we rely on upper layer to stop further updates */
-	jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
+	if (journal)
+		/* we rely on upper layer to stop further updates */
+		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 	return error;
 }
 
-- 
2.1.0

[PATCH 3/3] ext4: fold ext4_nojournal_sops into ext4_sops

[Theodore Ts'o]

There's no longer any need to have a separate set of super_operations
for nojournal mode.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---
 fs/ext4/super.c | 27 +--------------------------
 1 file changed, 1 insertion(+), 26 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 921d5b4..e747b97 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1123,27 +1123,6 @@ static const struct super_operations ext4_sops = {
 	.bdev_try_to_free_page = bdev_try_to_free_page,
 };
 
-static const struct super_operations ext4_nojournal_sops = {
-	.alloc_inode	= ext4_alloc_inode,
-	.destroy_inode	= ext4_destroy_inode,
-	.write_inode	= ext4_write_inode,
-	.dirty_inode	= ext4_dirty_inode,
-	.drop_inode	= ext4_drop_inode,
-	.evict_inode	= ext4_evict_inode,
-	.sync_fs	= ext4_sync_fs,
-	.freeze_fs	= ext4_freeze,
-	.unfreeze_fs	= ext4_unfreeze,
-	.put_super	= ext4_put_super,
-	.statfs		= ext4_statfs,
-	.remount_fs	= ext4_remount,
-	.show_options	= ext4_show_options,
-#ifdef CONFIG_QUOTA
-	.quota_read	= ext4_quota_read,
-	.quota_write	= ext4_quota_write,
-#endif
-	.bdev_try_to_free_page = bdev_try_to_free_page,
-};

Re: [PATCH 2/3] ext4: support freezing ext2 (nojournal) file systems

[Andreas Dilger]

[-- Attachment #1: Type: text/plain, Size: 1083 bytes --]

On Sep 18, 2014, at 2:26 PM, Theodore Ts'o <tytso@mit.edu> wrote:
> Through an oversight, when we added nojournal support to ext4, we
> didn't add support to allow file system freezing.  This is relatively
> easy to add, so let's do it.
> 
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> Reported-by: Dexuan Cui <decui@microsoft.com>
> ---
> fs/ext4/super.c | 27 ++++++++++++++++-----------
> 1 file changed, 16 insertions(+), 11 deletions(-)
> 
> @@ -4758,23 +4760,26 @@ static int ext4_freeze(struct super_block *sb)
> 
> 	journal = EXT4_SB(sb)->s_journal;
[snip]
> 	/* Journal blocked and flushed, clear needs_recovery flag. */
> 	EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
> 	error = ext4_commit_super(sb, 1);
> out:
> -	/* we rely on upper layer to stop further updates */
> -	jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
> +	if (journal)
> +		/* we rely on upper layer to stop further updates */
> +		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);

This could use "journal" directly instead of "EXT4_SB(sb)->s_journal"

Cheers, Andreas






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Re: [PATCH 2/3] ext4: support freezing ext2 (nojournal) file systems

[Theodore Ts'o]

On Thu, Sep 18, 2014 at 02:46:34PM -0600, Andreas Dilger wrote:
> > +	if (journal)
> > +		/* we rely on upper layer to stop further updates */
> > +		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
> 
> This could use "journal" directly instead of "EXT4_SB(sb)->s_journal"

Good point, done.

				- Ted

Re: [PATCH 1/3] ext4: fold ext4_sync_fs_nojournal() into ext4_sync_fs()

[Jan Kara]

On Thu 18-09-14 16:26:27, Ted Tso wrote:
> This allows us to eliminate duplicate code, and eventually allow us to
> also fold ext4_sops and ext4_nojournal_sops together.
> 
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  Looks good. You can add:
Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  fs/ext4/super.c | 36 +++++++++++++-----------------------
>  1 file changed, 13 insertions(+), 23 deletions(-)
> 
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 115e27d..4770c98 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -70,7 +70,6 @@ static void ext4_mark_recovery_complete(struct super_block *sb,
>  static void ext4_clear_journal_err(struct super_block *sb,
>  				   struct ext4_super_block *es);
>  static int ext4_sync_fs(struct super_block *sb, int wait);
> -static int ext4_sync_fs_nojournal(struct super_block *sb, int wait);
>  static int ext4_remount(struct super_block *sb, int *flags, char *data);
>  static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
>  static int ext4_unfreeze(struct super_block *sb);
> @@ -1131,7 +1130,7 @@ static const struct super_operations ext4_nojournal_sops = {
>  	.dirty_inode	= ext4_dirty_inode,
>  	.drop_inode	= ext4_drop_inode,
>  	.evict_inode	= ext4_evict_inode,
> -	.sync_fs	= ext4_sync_fs_nojournal,
> +	.sync_fs	= ext4_sync_fs,
>  	.put_super	= ext4_put_super,
>  	.statfs		= ext4_statfs,
>  	.remount_fs	= ext4_remount,
> @@ -4718,15 +4717,19 @@ static int ext4_sync_fs(struct super_block *sb, int wait)
>  	 * being sent at the end of the function. But we can skip it if
>  	 * transaction_commit will do it for us.
>  	 */
> -	target = jbd2_get_latest_transaction(sbi->s_journal);
> -	if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
> -	    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
> +	if (sbi->s_journal) {
> +		target = jbd2_get_latest_transaction(sbi->s_journal);
> +		if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
> +		    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
> +			needs_barrier = true;
> +
> +		if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
> +			if (wait)
> +				ret = jbd2_log_wait_commit(sbi->s_journal,
> +							   target);
> +		}
> +	} else if (wait && test_opt(sb, BARRIER))
>  		needs_barrier = true;
> -
> -	if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
> -		if (wait)
> -			ret = jbd2_log_wait_commit(sbi->s_journal, target);
> -	}
>  	if (needs_barrier) {
>  		int err;
>  		err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
> @@ -4737,19 +4740,6 @@ static int ext4_sync_fs(struct super_block *sb, int wait)
>  	return ret;
>  }
>  
> -static int ext4_sync_fs_nojournal(struct super_block *sb, int wait)
> -{
> -	int ret = 0;
> -
> -	trace_ext4_sync_fs(sb, wait);
> -	flush_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
> -	dquot_writeback_dquots(sb, -1);
> -	if (wait && test_opt(sb, BARRIER))
> -		ret = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
> -
> -	return ret;
> -}
> -
>  /*
>   * LVM calls this function before a (read-only) snapshot is created.  This
>   * gives us a chance to flush the journal completely and mark the fs clean.
> -- 
> 2.1.0
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
-- 
Jan Kara <jack@suse.cz>
SUSE Labs, CR

Re: [PATCH 3/3] ext4: fold ext4_nojournal_sops into ext4_sops

[Jan Kara]

On Thu 18-09-14 16:26:29, Ted Tso wrote:
> There's no longer any need to have a separate set of super_operations
> for nojournal mode.
> 
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  Nice :) You can add:
Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  fs/ext4/super.c | 27 +--------------------------
>  1 file changed, 1 insertion(+), 26 deletions(-)
> 
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 921d5b4..e747b97 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -1123,27 +1123,6 @@ static const struct super_operations ext4_sops = {
>  	.bdev_try_to_free_page = bdev_try_to_free_page,
>  };
>  
> -static const struct super_operations ext4_nojournal_sops = {
> -	.alloc_inode	= ext4_alloc_inode,
> -	.destroy_inode	= ext4_destroy_inode,
> -	.write_inode	= ext4_write_inode,
> -	.dirty_inode	= ext4_dirty_inode,
> -	.drop_inode	= ext4_drop_inode,
> -	.evict_inode	= ext4_evict_inode,
> -	.sync_fs	= ext4_sync_fs,
> -	.freeze_fs	= ext4_freeze,
> -	.unfreeze_fs	= ext4_unfreeze,
> -	.put_super	= ext4_put_super,
> -	.statfs		= ext4_statfs,
> -	.remount_fs	= ext4_remount,
> -	.show_options	= ext4_show_options,
> -#ifdef CONFIG_QUOTA
> -	.quota_read	= ext4_quota_read,
> -	.quota_write	= ext4_quota_write,
> -#endif
> -	.bdev_try_to_free_page = bdev_try_to_free_page,
> -};
> -
>  static const struct export_operations ext4_export_ops = {
>  	.fh_to_dentry = ext4_fh_to_dentry,
>  	.fh_to_parent = ext4_fh_to_parent,
> @@ -3941,11 +3920,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
>  	/*
>  	 * set up enough so that it can read an inode
>  	 */
> -	if (!test_opt(sb, NOLOAD) &&
> -	    EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
> -		sb->s_op = &ext4_sops;
> -	else
> -		sb->s_op = &ext4_nojournal_sops;
> +	sb->s_op = &ext4_sops;
>  	sb->s_export_op = &ext4_export_ops;
>  	sb->s_xattr = ext4_xattr_handlers;
>  #ifdef CONFIG_QUOTA
> -- 
> 2.1.0
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
-- 
Jan Kara <jack@suse.cz>
SUSE Labs, CR

Re: [PATCH 2/3] ext4: support freezing ext2 (nojournal) file systems

[Jan Kara]

On Thu 18-09-14 16:26:28, Ted Tso wrote:
> Through an oversight, when we added nojournal support to ext4, we
> didn't add support to allow file system freezing.  This is relatively
> easy to add, so let's do it.
> 
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> Reported-by: Dexuan Cui <decui@microsoft.com>
  Looks good. You can add:
Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  fs/ext4/super.c | 27 ++++++++++++++++-----------
>  1 file changed, 16 insertions(+), 11 deletions(-)
> 
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 4770c98..921d5b4 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -1131,6 +1131,8 @@ static const struct super_operations ext4_nojournal_sops = {
>  	.drop_inode	= ext4_drop_inode,
>  	.evict_inode	= ext4_evict_inode,
>  	.sync_fs	= ext4_sync_fs,
> +	.freeze_fs	= ext4_freeze,
> +	.unfreeze_fs	= ext4_unfreeze,
>  	.put_super	= ext4_put_super,
>  	.statfs		= ext4_statfs,
>  	.remount_fs	= ext4_remount,
> @@ -4758,23 +4760,26 @@ static int ext4_freeze(struct super_block *sb)
>  
>  	journal = EXT4_SB(sb)->s_journal;
>  
> -	/* Now we set up the journal barrier. */
> -	jbd2_journal_lock_updates(journal);
> +	if (journal) {
> +		/* Now we set up the journal barrier. */
> +		jbd2_journal_lock_updates(journal);
>  
> -	/*
> -	 * Don't clear the needs_recovery flag if we failed to flush
> -	 * the journal.
> -	 */
> -	error = jbd2_journal_flush(journal);
> -	if (error < 0)
> -		goto out;
> +		/*
> +		 * Don't clear the needs_recovery flag if we failed to
> +		 * flush the journal.
> +		 */
> +		error = jbd2_journal_flush(journal);
> +		if (error < 0)
> +			goto out;
> +	}
>  
>  	/* Journal blocked and flushed, clear needs_recovery flag. */
>  	EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
>  	error = ext4_commit_super(sb, 1);
>  out:
> -	/* we rely on upper layer to stop further updates */
> -	jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
> +	if (journal)
> +		/* we rely on upper layer to stop further updates */
> +		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
>  	return error;
>  }
>  
> -- 
> 2.1.0
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
-- 
Jan Kara <jack@suse.cz>
SUSE Labs, CR