[PATCH] Add assert for inode->i_io_list in inode_io_list_move_locked.

[Jchao Sun <sunjunchao2870@gmail.com>]

Cause of patch b35250c, inode->i_io_list will not only be protected by
wb->list_lock, but also inode->i_lock. And in that patch, Added some assert
for inode->i_lock in some functions except inode_io_list_move_locked.
Should complete it to describe the semantics more clearly. Modified comment
correspondingly.

Signed-off-by: Jchao Sun <sunjunchao2870@gmail.com>
---
 fs/fs-writeback.c | 1 +
 fs/inode.c        | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 591fe9cf1659..5a761b39f36c 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -120,6 +120,7 @@ static bool inode_io_list_move_locked(struct inode *inode,
 				      struct list_head *head)
 {
 	assert_spin_locked(&wb->list_lock);
+	assert_spin_locked(&inode->i_lock);
 
 	list_move(&inode->i_io_list, head);
 
diff --git a/fs/inode.c b/fs/inode.c
index 9d9b422504d1..bd4da9c5207e 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -27,7 +27,7 @@
  * Inode locking rules:
  *
  * inode->i_lock protects:
- *   inode->i_state, inode->i_hash, __iget()
+ *   inode->i_state, inode->i_hash, __iget(), inode->i_io_list
  * Inode LRU list locks protect:
  *   inode->i_sb->s_inode_lru, inode->i_lru
  * inode->i_sb->s_inode_list_lock protects:
-- 
2.17.1