jbd2, ext4, ocfs2: introduce/use journal callbacks j_submit|finish_inode_data_buffers()

Introduce journal callbacks to allow different behaviors
for an inode in journal_submit|finish_inode_data_buffers().

The existing users of the current behavior (ext4, ocfs2)
are adapted to use the previously exported functions
that implement the current behavior.

Users are callers of jbd2_journal_inode_ranged_write|wait(),
which adds the inode to the transaction's inode list with
the JI_WRITE|WAIT_DATA flags. Only ext4 and ocfs2 in-tree.

Both CONFIG_EXT4_FS and CONFIG_OCSFS2_FS select CONFIG_JBD2,
which builds fs/jbd2/commit.c and journal.c that define and
export the functions, so we can call directly in ext4/ocfs2.

Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20201006004841.600488-3-mfo@canonical.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

1 files changed, 18 insertions, 12 deletions

diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index f79b86b4241f..6252b4c50666 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -197,6 +197,12 @@ int jbd2_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
 		.range_end = jinode->i_dirty_end,
 	};
 
+	/*
+	 * submit the inode data buffers. We use writepage
+	 * instead of writepages. Because writepages can do
+	 * block allocation with delalloc. We need to write
+	 * only allocated blocks here.
+	 */
 	return generic_writepages(mapping, &wbc);
 }
 
@@ -220,16 +226,13 @@ static int journal_submit_data_buffers(journal_t *journal,
 			continue;
 		jinode->i_flags |= JI_COMMIT_RUNNING;
 		spin_unlock(&journal->j_list_lock);
-		/*
-		 * submit the inode data buffers. We use writepage
-		 * instead of writepages. Because writepages can do
-		 * block allocation  with delalloc. We need to write
-		 * only allocated blocks here.
-		 */
+		/* submit the inode data buffers. */
 		trace_jbd2_submit_inode_data(jinode->i_vfs_inode);
-		err = jbd2_journal_submit_inode_data_buffers(jinode);
-		if (!ret)
-			ret = err;
+		if (journal->j_submit_inode_data_buffers) {
+			err = journal->j_submit_inode_data_buffers(jinode);
+			if (!ret)
+				ret = err;
+		}
 		spin_lock(&journal->j_list_lock);
 		J_ASSERT(jinode->i_transaction == commit_transaction);
 		jinode->i_flags &= ~JI_COMMIT_RUNNING;
@@ -267,9 +270,12 @@ static int journal_finish_inode_data_buffers(journal_t *journal,
 			continue;
 		jinode->i_flags |= JI_COMMIT_RUNNING;
 		spin_unlock(&journal->j_list_lock);
-		err = jbd2_journal_finish_inode_data_buffers(jinode);
-		if (!ret)
-			ret = err;
+		/* wait for the inode data buffers writeout. */
+		if (journal->j_finish_inode_data_buffers) {
+			err = journal->j_finish_inode_data_buffers(jinode);
+			if (!ret)
+				ret = err;
+		}
 		spin_lock(&journal->j_list_lock);
 		jinode->i_flags &= ~JI_COMMIT_RUNNING;
 		smp_mb();