ext4: remove unused ext4_sb_info members

Not that these take up a lot of room, but the structure is long enough
as it is, and there's no need to confuse people with these various
undocumented & unused structure members...
Signed-off-by: NEric Sandeen <sandeen@redaht.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

fs/ext4/ext4.h

@@ -1089,7 +1089,6 @@ struct ext4_sb_info {
 	struct completion s_kobj_unregister;
 
 	/* Journaling */
-	struct inode *s_journal_inode;
 	struct journal_s *s_journal;
 	struct list_head s_orphan;
 	struct mutex s_orphan_lock;
@@ -1122,10 +1121,7 @@ struct ext4_sb_info {
 	/* for buddy allocator */
 	struct ext4_group_info ***s_group_info;
 	struct inode *s_buddy_cache;
-	long s_blocks_reserved;
-	spinlock_t s_reserve_lock;
 	spinlock_t s_md_lock;
-	tid_t s_last_transaction;
 	unsigned short *s_mb_offsets;
 	unsigned int *s_mb_maxs;
 
@@ -1143,7 +1139,6 @@ struct ext4_sb_info {
 	unsigned long s_mb_last_start;
 
 	/* stats for buddy allocator */
-	spinlock_t s_mb_pa_lock;
 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
 	atomic_t s_bal_success;	/* we found long enough chunks */
 	atomic_t s_bal_allocated;	/* in blocks */