jbd2: remove journal_head from descriptor buffers

Similarly as for metadata buffers, also log descriptor buffers don't
really need the journal head. So strip it and remove BJ_LogCtl list.

Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/jbd2/revoke.c b/fs/jbd2/revoke.c
index f30b80b..198c9c1 100644
--- a/fs/jbd2/revoke.c
+++ b/fs/jbd2/revoke.c
@@ -122,9 +122,10 @@
 
 #ifdef __KERNEL__
 static void write_one_revoke_record(journal_t *, transaction_t *,
-				    struct journal_head **, int *,
+				    struct list_head *,
+				    struct buffer_head **, int *,
 				    struct jbd2_revoke_record_s *, int);
-static void flush_descriptor(journal_t *, struct journal_head *, int, int);
+static void flush_descriptor(journal_t *, struct buffer_head *, int, int);
 #endif
 
 /* Utility functions to maintain the revoke table */
@@ -531,9 +532,10 @@
  */
 void jbd2_journal_write_revoke_records(journal_t *journal,
 				       transaction_t *transaction,
+				       struct list_head *log_bufs,
 				       int write_op)
 {
-	struct journal_head *descriptor;
+	struct buffer_head *descriptor;
 	struct jbd2_revoke_record_s *record;
 	struct jbd2_revoke_table_s *revoke;
 	struct list_head *hash_list;
@@ -553,7 +555,7 @@
 		while (!list_empty(hash_list)) {
 			record = (struct jbd2_revoke_record_s *)
 				hash_list->next;
-			write_one_revoke_record(journal, transaction,
+			write_one_revoke_record(journal, transaction, log_bufs,
 						&descriptor, &offset,
 						record, write_op);
 			count++;
@@ -573,13 +575,14 @@
 
 static void write_one_revoke_record(journal_t *journal,
 				    transaction_t *transaction,
-				    struct journal_head **descriptorp,
+				    struct list_head *log_bufs,
+				    struct buffer_head **descriptorp,
 				    int *offsetp,
 				    struct jbd2_revoke_record_s *record,
 				    int write_op)
 {
 	int csum_size = 0;
-	struct journal_head *descriptor;
+	struct buffer_head *descriptor;
 	int offset;
 	journal_header_t *header;
 
@@ -609,26 +612,26 @@
 		descriptor = jbd2_journal_get_descriptor_buffer(journal);
 		if (!descriptor)
 			return;
-		header = (journal_header_t *) &jh2bh(descriptor)->b_data[0];
+		header = (journal_header_t *)descriptor->b_data;
 		header->h_magic     = cpu_to_be32(JBD2_MAGIC_NUMBER);
 		header->h_blocktype = cpu_to_be32(JBD2_REVOKE_BLOCK);
 		header->h_sequence  = cpu_to_be32(transaction->t_tid);
 
 		/* Record it so that we can wait for IO completion later */
-		JBUFFER_TRACE(descriptor, "file as BJ_LogCtl");
-		jbd2_journal_file_buffer(descriptor, transaction, BJ_LogCtl);
+		BUFFER_TRACE(descriptor, "file in log_bufs");
+		jbd2_file_log_bh(log_bufs, descriptor);
 
 		offset = sizeof(jbd2_journal_revoke_header_t);
 		*descriptorp = descriptor;
 	}
 
 	if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT)) {
-		* ((__be64 *)(&jh2bh(descriptor)->b_data[offset])) =
+		* ((__be64 *)(&descriptor->b_data[offset])) =
 			cpu_to_be64(record->blocknr);
 		offset += 8;
 
 	} else {
-		* ((__be32 *)(&jh2bh(descriptor)->b_data[offset])) =
+		* ((__be32 *)(&descriptor->b_data[offset])) =
 			cpu_to_be32(record->blocknr);
 		offset += 4;
 	}
@@ -636,8 +639,7 @@
 	*offsetp = offset;
 }
 
-static void jbd2_revoke_csum_set(journal_t *j,
-				 struct journal_head *descriptor)
+static void jbd2_revoke_csum_set(journal_t *j, struct buffer_head *bh)
 {
 	struct jbd2_journal_revoke_tail *tail;
 	__u32 csum;
@@ -645,12 +647,10 @@
 	if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2))
 		return;
 
-	tail = (struct jbd2_journal_revoke_tail *)
-			(jh2bh(descriptor)->b_data + j->j_blocksize -
+	tail = (struct jbd2_journal_revoke_tail *)(bh->b_data + j->j_blocksize -
 			sizeof(struct jbd2_journal_revoke_tail));
 	tail->r_checksum = 0;
-	csum = jbd2_chksum(j, j->j_csum_seed, jh2bh(descriptor)->b_data,
-			   j->j_blocksize);
+	csum = jbd2_chksum(j, j->j_csum_seed, bh->b_data, j->j_blocksize);
 	tail->r_checksum = cpu_to_be32(csum);
 }
 
@@ -662,25 +662,24 @@
  */
 
 static void flush_descriptor(journal_t *journal,
-			     struct journal_head *descriptor,
+			     struct buffer_head *descriptor,
 			     int offset, int write_op)
 {
 	jbd2_journal_revoke_header_t *header;
-	struct buffer_head *bh = jh2bh(descriptor);
 
 	if (is_journal_aborted(journal)) {
-		put_bh(bh);
+		put_bh(descriptor);
 		return;
 	}
 
-	header = (jbd2_journal_revoke_header_t *) jh2bh(descriptor)->b_data;
+	header = (jbd2_journal_revoke_header_t *)descriptor->b_data;
 	header->r_count = cpu_to_be32(offset);
 	jbd2_revoke_csum_set(journal, descriptor);
 
-	set_buffer_jwrite(bh);
-	BUFFER_TRACE(bh, "write");
-	set_buffer_dirty(bh);
-	write_dirty_buffer(bh, write_op);
+	set_buffer_jwrite(descriptor);
+	BUFFER_TRACE(descriptor, "write");
+	set_buffer_dirty(descriptor);
+	write_dirty_buffer(descriptor, write_op);
 }
 #endif